Healthcare analytics, AI solutions for biological big data, providing an AI platform for the biotech, life sciences, medical and pharmaceutical industries, as well as for related technological approaches, i.e., curation and text analysis with machine learning and other activities related to AI applications to these industries.
“This milestone makes AISAP the first company in the world to secure FDA clearance in the CADx pathway for the comprehensive diagnosis of structural heart diseases using POCUS,”
Cardio is a cloud-based platform that includes four modules for the computer-assist diagnosis (CADx) of valvular pathologies and eight key cardiac measurements. Its advanced AI algorithms can evaluate a patient’s left ventricle ejection fraction, right and left ventricular dimensions, right ventricular fractional area change, atrial areas, ascending aorta diameter and inferior vena cava diameter in addition to identifying aortic stenosis or mitral, tricuspid or aortic regurgitation.
The platform, trained on more than 24 million echocardiography clips, was designed to help even inexperienced users scan and diagnose a majority of common heart issues within minutes without leaving the patient’s side. In addition, it can communicate with equipment manufactured by a variety of vendors, directing data to a physician’s electronic health record or PACS system as needed.
Ehud Raanani, MD, co-founder of AISAP and director of the Leviev Cardiovascular and Thoracic Center at Sheba Medical Center, said in a statement. “It marks a big step in our goal of delivering point-of-care assisted diagnosis, or POCAD, with unparalleled scalability and accessibility—from the largest academic centers to the most remote rural locations.”
Smadar Kort, MD, system director of noninvasive cardiac imaging at Stony Brook Medicine, who has experience with the platform
said:
“We know that structural heart disease and heart failure are the leading causes of hospitalization and morbidity in the U.S. Enabling a wide variety of qualified physicians to quickly and accurately diagnose these conditions at the bedside could lead to earlier detection and treatment, and better patient outcomes, as well as greater efficiencies and cost savings to health systems, while ultimately saving countless lives.”
The Implications and Association of Stair Climbing with Atherosclerotic Cardiovascular Disease (ASCVD)
Reporter: Arav Gandhi, Research Assistant 2, Domain Content: Cardiovascular Diseases, Series A
Atherosclerotic Cardiovascular Disease (ASCVD) is a condition in which cholesterol builds up in the arteries to an extent that develops long-term complications for other areas of the body and in some cases emergence of symptoms such as chest pain, dizziness, and shortness of breath are presented and reported to PCPs. This can cause a strain on daily activities such as walking and especially may be noticed when climbing stairs which represents a form of exertion related to elevation. To further understand the significance of ASCVD upon daily activities, Zimin Song et al. (2023), using a sample of 458,860 participants (55.9% female) from the UK Biobank, aimed to evaluate the intensity of stair climbing and the present risk of ASCVD. All participants had a history of ASCVD, put at risk for ASCVD, or had a recorded levels of genetic risk.
Prior to the study, all participants underwent blood tests and other necessary measurements. During the study, the researchers assessed the intensity of stair climbing through a self-reported structure in which participants were asked a set of questions addressing the duration of climbing stairs and whether they continued to climb. Additional questionnaires were administered to collect sociodemographic characteristics, lifestyle factors, and health status. Following the conclusion of the study, the researchers found, with an application of statistical analysis, that over a period of 12.5 years individuals with a higher intensity of stair climbing were of younger age, female, and non-regular smokers. Moreover, those individuals exemplified a higher level of education and income along with healthier dietary habits and prolonged exercise durations. Beyond demographic characteristics, researchers found that when individuals especially those with a family history of ASCVD increased the intensity of stair climbing, the risk of ASCVD was reduced. This remained consistent across other groups of participants finding an association between the intensity of stair climbing and the risk of ASCVD.
Ultimately, given the large sample of UK adults, the findings conclude that high-intensity climbing, or climbing more than five flights of stairs daily was associated with over a 20% reduction in risk of obtaining ASCVD. Despite the variance of disease tendencies among individuals, active engagement in stair climbing can significantly reduce the risk of ASCVD in contrast to those who discontinued stair climbing leading to a higher risk of ASCVD. However, the intensity of stair climbing was limited to a threshold in which it no longer decreased the risk of ASCVD.
Simply climbing stairs can be considered a prevention strategy for ASCVD, but the application of active engagement in physical activities may be associated with reducing the risk of obtaining other diseases. For instance, the positive effects of stair climbing on reducing the risk of ASCVD may also apply to
atrial fibrillation,
diabetes, and
hypertension.
Other existing studies find associations with a
lower risk of metabolic syndrome, and even
mortality.
In contrast to structured sports and exercise, stair climbing proves to be an effective method with minimal equipment and low cost that allows an individual to practice cardiorespiratory fitness reducing the risks of various diseases while improving their overall standard of life. Although further studies need to be conducted on the extent to which intense stair climbing improves different areas of the body and what diseases it helps prevent, current studies prove the effects of stair climbing to be beneficial to an extent in which individuals should be encouraged in incorporate it in their daily routine yielding both short-term and long-term benefits.
To learn more about the topic, check out the article below.
SOURCE
Song Z, Wan L, Wang W, et al. Daily stair climbing, disease susceptibility, and risk of atherosclerotic cardiovascular disease: A prospective cohort study. Atherosclerosis. 2023:117300. doi: 10.1016/j.atherosclerosis.2023.117300
Other related articles published in this Open Access Online Scientific Journal include the following:
Archive for the ‘Atherogenic Processes & Pathology’ Category
The Current Impact and Future of Technology within Cardiovascular Surgery
Reporter: Arav Gandhi, Research Assistant 2, Domain Content: Cardiovascular Diseases, Series A
Medical professionals have been able to explore new methods and strategies to tackle complex medical conditions, especially with the limitations of other pre-existing conditions. For instance, through recent cardiology advancements, if the patient requires a heart transplant due to heart failure disease and is unable to undergo a human donor heart transplant as a result of pre-existing disease conditions or existing internal bleeding complications, there is a greater alternative to leaving it untreated. Medical professionals developed alternatives to humman donor transplants. One such a solution is transplanting a genetically modified pig heart, a new advanced experimental procedure that has been used over recent cases. Researchers continue to develop solutions that not only presents an alternative to current methods but also continue to maximize the potential of medical devices technology and of our understanding of medicine.
Recently, cardiologists at Henry Ford Health Hospital found themselves as the first physicians in the United States to employ an investigational device to treat a patient with severe tricuspid regurgitation. Having never been experimented upon prior to the situation, the K-Clip Transvascular Tricuspid Repair System utilizes a corkscrew anchor, which then clips the ring-shaped region of the valve. Similar to most dire situations where new technology is used, the patient, an 85-year-old male, continued to experience worsening symptoms for an entire year. His tricuspid valve, key in ensuring blood flow to the right ventricle and then to the pulmonary valve, was enlarged from his condition, resulting in the mass of his heart tripling in size. Cardiologists were then prompted to either utilize the new procedure or go untreated. With optimism, the cardiologists selected the procedure and applied a unique approach of an incision through the neck to reduce further risks of opening the chest and placed the device using real-time 3D imaging and 4D modeling. The medical professionals followed a minimally invasive procedure through the neck in contrast to traditional open-heart surgery and effectively employed recent advancements in imaging and modeling to ensure precision when planting the device, a new artificial tricuspid valve. The patient was later reported to have experience improve in the valve condition and a significant decrease in leakage, along with an improvement in his overall quality of life.
As a result, researchers should continue to focus not only on understanding undiscovered diseases and complications but also on developing alternative solutions to resolve cases in which the best practice approach can not be applied.
With the advancements in technology, the true extent of its application can not be discovered without experimentation and the application of imaging and other devices to resolve certain conditions. Beyond the technology itself, the introduction of new methods allows for less costly treatment plans, aiding especially those who come from a low-income background and currently struggle to afford basic healthcare. In the united States they are covered by MedicAid at all ages and by Medicare at age 65 and beyond. This is not the case in many countries in the World excluding Europe. The overall development of the field of medicine through advancement of medical technologies can indirectly allow for a improvement to the overall Global health care delivery and ascertain an increased life expectancies. This is primarily true, chiefly, in developing countries where established surgeries to resolve complex medical conditions still have the ability to achieve life-changing quality of life and longevity.
To learn more about the topic, check out the article below.
Chapter 13: Valve Replacement, Valve Implantation and Valve Repair
The Voice of Series A Content Consultant: Justin D. Pearlman, MD, PhD, FACC
As catheter techniques evolved to compete with bypass surgery they progressed from balloon cracking of obstructive lesions (POBA=plain old balloon angioplasty) to placement of stents (wire fences). Surgeons sometimes use in-stent valves, and now devices analogous to in-stent valves can be placed by catheter for valve replacement in patients with too much co-morbidity to go through heart surgery. Aortic valve replacement by stent (TAVR) has had sufficient success to be considered for all patients who have sufficient impairment to merit intervention. The diameter is large, so a vascular surgeon participates in the arterial access and repair of the access site.
13.5 Tricuspid Valve
13.5.1 First-in-Man Mitral Valve Repairs Device used for Tricuspid Valve Repair: Cardioband used by University Hospital Zurich Heart Team
The following paper in Cells describes the discovery of protein interactors of endoglin, which is recruited to membranes at the TGF-β receptor complex upon TGF-β signaling. Interesting a carbohydrate binding protein, galectin-3, and an E3-ligase, TRIM21, were found to be unique interactors within this complex.
Gallardo-Vara E, Ruiz-Llorente L, Casado-Vela J, Ruiz-Rodríguez MJ, López-Andrés N, Pattnaik AK, Quintanilla M, Bernabeu C. Endoglin Protein Interactome Profiling Identifies TRIM21 and Galectin-3 as New Binding Partners. Cells. 2019 Sep 13;8(9):1082. doi: 10.3390/cells8091082. PMID: 31540324; PMCID: PMC6769930.
Abstract
Endoglin is a 180-kDa glycoprotein receptor primarily expressed by the vascular endothelium and involved in cardiovascular disease and cancer. Heterozygous mutations in the endoglin gene (ENG) cause hereditary hemorrhagic telangiectasia type 1, a vascular disease that presents with nasal and gastrointestinal bleeding, skin and mucosa telangiectases, and arteriovenous malformations in internal organs. A circulating form of endoglin (alias soluble endoglin, sEng), proteolytically released from the membrane-bound protein, has been observed in several inflammation-related pathological conditions and appears to contribute to endothelial dysfunction and cancer development through unknown mechanisms. Membrane-bound endoglin is an auxiliary component of the TGF-β receptor complex and the extracellular region of endoglin has been shown to interact with types I and II TGF-β receptors, as well as with BMP9 and BMP10 ligands, both members of the TGF-β family. To search for novel protein interactors, we screened a microarray containing over 9000 unique human proteins using recombinant sEng as bait. We find that sEng binds with high affinity, at least, to 22 new proteins. Among these, we validated the interaction of endoglin with galectin-3, a secreted member of the lectin family with capacity to bind membrane glycoproteins, and with tripartite motif-containing protein 21 (TRIM21), an E3 ubiquitin-protein ligase. Using human endothelial cells and Chinese hamster ovary cells, we showed that endoglin co-immunoprecipitates and co-localizes with galectin-3 or TRIM21. These results open new research avenues on endoglin function and regulation.
Endoglin is an auxiliary TGF-β co-receptor predominantly expressed in endothelial cells, which is involved in vascular development, repair, homeostasis, and disease [1,2,3,4]. Heterozygous mutations in the human ENDOGLIN gene (ENG) cause hereditary hemorrhagic telangiectasia (HHT) type 1, a vascular disease associated with nasal and gastrointestinal bleeds, telangiectases on skin and mucosa and arteriovenous malformations in the lung, liver, and brain [4,5,6]. The key role of endoglin in the vasculature is also illustrated by the fact that endoglin-KO mice die in utero due to defects in the vascular system [7]. Endoglin expression is markedly upregulated in proliferating endothelial cells involved in active angiogenesis, including the solid tumor neovasculature [8,9]. For this reason, endoglin has become a promising target for the antiangiogenic treatment of cancer [10,11,12]. Endoglin is also expressed in cancer cells where it can behave as both a tumor suppressor in prostate, breast, esophageal, and skin carcinomas [13,14,15,16] and a promoter of malignancy in melanoma and Ewing’s sarcoma [17]. Ectodomain shedding of membrane-bound endoglin may lead to a circulating form of the protein, also known as soluble endoglin (sEng) [18,19,20]. Increased levels of sEng have been found in several vascular-related pathologies, including preeclampsia, a disease of high prevalence in pregnant women which, if left untreated, can lead to serious and even fatal complications for both mother and baby [2,18,19,21]. Interestingly, several lines of evidence support a pathogenic role of sEng in the vascular system, including endothelial dysfunction, antiangiogenic activity, increased vascular permeability, inflammation-associated leukocyte adhesion and transmigration, and hypertension [18,22,23,24,25,26,27]. Because of its key role in vascular pathology, a large number of studies have addressed the structure and function of endoglin at the molecular level, in order to better understand its mechanism of action.
Galectin-3 Interacts with Endoglin in Cells
Galectin-3 is a secreted member of the lectin family with the capacity to bind membrane glycoproteins like endoglin and is involved in the pathogenesis of many human diseases [52]. We confirmed the protein screen data for galectin-3, as evidenced by two-way co-immunoprecipitation of endoglin and galectin-3 upon co-transfection in CHO-K1 cells. As shown in Figure 1A, galectin-3 and endoglin were efficiently transfected, as demonstrated by Western blot analysis in total cell extracts. No background levels of endoglin were observed in control cells transfected with the empty vector (Ø). By contrast, galectin-3 could be detected in all samples but, as expected, showed an increased signal in cells transfected with the galectin-3 expression vector. Co-immunoprecipitation studies of these cell lysates showed that galectin-3 was present in endoglin immunoprecipitates (Figure 1B). Conversely, endoglin was also detected in galectin-3 immunoprecipitates (Figure 1C).
Figure 1. Protein–protein association between galectin-3 and endoglin. (A–C). Co-immunoprecipitation of galectin-3 and endoglin. CHO-K1 cells were transiently transfected with pcEXV-Ø (Ø), pcEXV–HA–EngFL (Eng) and pcDNA3.1–Gal-3 (Gal3) expression vectors. (A) Total cell lysates (TCL) were analyzed by SDS-PAGE under reducing conditions, followed by Western blot (WB) analysis using specific antibodies to endoglin, galectin-3 and β-actin (loading control). Cell lysates were subjected to immunoprecipitation (IP) with anti-endoglin (B) or anti-galectin-3 (C) antibodies, followed by SDS-PAGE under reducing conditions and WB analysis with anti-endoglin or anti-galectin-3 antibodies, as indicated. Negative controls with an IgG2b (B) and IgG1 (C) were included. (D) Protein-protein interactions between galectin-3 and endoglin using Bio-layer interferometry (BLItz). The Ni–NTA biosensors tips were loaded with 7.3 µM recombinant human galectin-3/6xHis at the C-terminus (LGALS3), and protein binding was measured against 0.1% BSA in PBS (negative control) or 4.1 µM soluble endoglin (sEng). Kinetic sensorgrams were obtained using a single channel ForteBioBLItzTM instrument.
Figure 2.Galectin-3 and endoglin co-localize in human endothelial cells. Human umbilical vein-derived endothelial cell (HUVEC) monolayers were fixed with paraformaldehyde, permeabilized with Triton X-100, incubated with the mouse mAb P4A4 anti-endoglin, washed, and incubated with a rabbit polyclonal anti-galectin-3 antibody (PA5-34819). Galectin-3 and endoglin were detected by immunofluorescence upon incubation with Alexa 647 goat anti-rabbit IgG (red staining) and Alexa 488 goat anti-mouse IgG (green staining) secondary antibodies, respectively. (A) Single staining of galectin-3 (red) and endoglin (green) at the indicated magnifications. (B) Merge images plus DAPI (nuclear staining in blue) show co-localization of galectin-3 and endoglin (yellow color). Representative images of five different experiments are shown.
Endoglin associates with the cullin-type E3 ligase TRIM21
Figure 3.Protein–protein association between TRIM21 and endoglin. (A–E) Co-immunoprecipitation of TRIM21 and endoglin. A,B. HUVEC monolayers were lysed and total cell lysates (TCL) were subjected to SDS-PAGE under reducing (for TRIM21 detection) or nonreducing (for endoglin detection) conditions, followed by Western blot (WB) analysis using antibodies to endoglin, TRIM21 or β-actin (A). HUVECs lysates were subjected to immunoprecipitation (IP) with anti-TRIM21 or negative control antibodies, followed by WB analysis with anti-endoglin (B). C,D. CHO-K1 cells were transiently transfected with pDisplay–HA–Mock (Ø), pDisplay–HA–EngFL (E) or pcDNA3.1–HA–hTRIM21 (T) expression vectors, as indicated. Total cell lysates (TCL) were subjected to SDS-PAGE under nonreducing conditions and WB analysis using specific antibodies to endoglin, TRIM21, and β-actin (C). Cell lysates were subjected to immunoprecipitation (IP) with anti-TRIM21 or anti-endoglin antibodies, followed by SDS-PAGE under reducing (upper panel) or nonreducing (lower panel) conditions and WB analysis with anti-TRIM21 or anti-endoglin antibodies. Negative controls of appropriate IgG were included (D). E. CHO-K1 cells were transiently transfected with pcDNA3.1–HA–hTRIM21 and pDisplay–HA–Mock (Ø), pDisplay–HA–EngFL (FL; full-length), pDisplay–HA–EngEC (EC; cytoplasmic-less) or pDisplay–HA–EngTMEC (TMEC; cytoplasmic-less) expression vectors, as indicated. Cell lysates were subjected to immunoprecipitation with anti-TRIM21, followed by SDS-PAGE under reducing conditions and WB analysis with anti-endoglin antibodies, as indicated. The asterisk indicates the presence of a nonspecific band. Mr, molecular reference; Eng, endoglin; TRIM, TRIM21. (F) Protein–protein interactions between TRIM21 and endoglin using Bio-layer interferometry (BLItz). The Ni–NTA biosensors tips were loaded with 5.4 µM recombinant human TRIM21/6xHis at the N-terminus (R052), and protein binding was measured against 0.1% BSA in PBS (negative control) or 4.1 µM soluble endoglin (sEng). Kinetic sensorgrams were obtained using a single channel ForteBioBLItzTM instrument.
Table 1. Human protein-array analysis of endoglin interactors1.
1 Microarrays containing over 9000 unique human proteins were screened using recombinant sEng as a probe. Protein interactors showing the highest scores (Z-score ≥2.0) are listed. GeneBank (https://www.ncbi.nlm.nih.gov/genbank/) and UniProtKB (https://www.uniprot.org/help/uniprotkb) accession numbers are indicated with a yellow or green background, respectively. The cellular compartment of each protein was obtained from the UniProtKB webpage. Proteins selected for further studies (TRIM21 and galectin-3) are indicated in bold type with blue background.
Note: the following are from NCBI Genbank and Genecards on TRIM21
Official Symbol TRIM21provided by HGNC Official Full Name tripartite motif containing 21provided by HGNC Primary source HGNC:HGNC:11312 See related Ensembl:ENSG00000132109MIM:109092;AllianceGenome:HGNC:11312 Gene type protein coding RefSeq status REVIEWED Organism Homo sapiens Lineage Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo Also known as SSA; RO52; SSA1; RNF81; Ro/SSA Summary This gene encodes a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The encoded protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. RoSSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Alternatively spliced transcript variants for this gene have been described but the full-length nature of only one has been determined. [provided by RefSeq, Jul 2008] Expression Ubiquitous expression in spleen (RPKM 15.5), appendix (RPKM 13.2) and 24 other tissues See more Orthologs mouseall NEW Try the new Gene table Try the new Transcript table
This gene encodes a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The encoded protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. RoSSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Alternatively spliced transcript variants for this gene have been described but the full-length nature of only one has been determined. [provided by RefSeq, Jul 2008]
E3 ubiquitin-protein ligase whose activity is dependent on E2 enzymes, UBE2D1, UBE2D2, UBE2E1 and UBE2E2. Forms a ubiquitin ligase complex in cooperation with the E2 UBE2D2 that is used not only for the ubiquitination of USP4 and IKBKB but also for its self-ubiquitination. Component of cullin-RING-based SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complexes such as SCF(SKP2)-like complexes. A TRIM21-containing SCF(SKP2)-like complex is shown to mediate ubiquitination of CDKN1B (‘Thr-187’ phosphorylated-form), thereby promoting its degradation by the proteasome. Monoubiquitinates IKBKB that will negatively regulates Tax-induced NF-kappa-B signaling. Negatively regulates IFN-beta production post-pathogen recognition by polyubiquitin-mediated degradation of IRF3. Mediates the ubiquitin-mediated proteasomal degradation of IgG1 heavy chain, which is linked to the VCP-mediated ER-associated degradation (ERAD) pathway. Promotes IRF8 ubiquitination, which enhanced the ability of IRF8 to stimulate cytokine genes transcription in macrophages. Plays a role in the regulation of the cell cycle progression. Enhances the decapping activity of DCP2. Exists as a ribonucleoprotein particle present in all mammalian cells studied and composed of a single polypeptide and one of four small RNA molecules. At least two isoforms are present in nucleated and red blood cells, and tissue specific differences in RO/SSA proteins have been identified. The common feature of these proteins is their ability to bind HY RNAs.2. Involved in the regulation of innate immunity and the inflammatory response in response to IFNG/IFN-gamma. Organizes autophagic machinery by serving as a platform for the assembly of ULK1, Beclin 1/BECN1 and ATG8 family members and recognizes specific autophagy targets, thus coordinating target recognition with assembly of the autophagic apparatus and initiation of autophagy. Acts as an autophagy receptor for the degradation of IRF3, hence attenuating type I interferon (IFN)-dependent immune responses (PubMed:26347139, 16297862, 16316627, 16472766, 16880511, 18022694, 18361920, 18641315, 18845142, 19675099). Represses the innate antiviral response by facilitating the formation of the NMI-IFI35 complex through ‘Lys-63’-linked ubiquitination of NMI (PubMed:26342464). ( RO52_HUMAN,P19474 )
Molecular function for TRIM21 Gene according to UniProtKB/Swiss-Prot
Function:
E3 ubiquitin-protein ligase whose activity is dependent on E2 enzymes, UBE2D1, UBE2D2, UBE2E1 and UBE2E2. Forms a ubiquitin ligase complex in cooperation with the E2 UBE2D2 that is used not only for the ubiquitination of USP4 and IKBKB but also for its self-ubiquitination. Component of cullin-RING-based SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complexes such as SCF(SKP2)-like complexes. A TRIM21-containing SCF(SKP2)-like complex is shown to mediate ubiquitination of CDKN1B (‘Thr-187’ phosphorylated-form), thereby promoting its degradation by the proteasome. Monoubiquitinates IKBKB that will negatively regulates Tax-induced NF-kappa-B signaling. Negatively regulates IFN-beta production post-pathogen recognition by polyubiquitin-mediated degradation of IRF3. Mediates the ubiquitin-mediated proteasomal degradation of IgG1 heavy chain, which is linked to the VCP-mediated ER-associated degradation (ERAD) pathway. Promotes IRF8 ubiquitination, which enhanced the ability of IRF8 to stimulate cytokine genes transcription in macrophages. Plays a role in the regulation of the cell cycle progression.
Endoglin Protein Interactome Profiling Identifies TRIM21 and Galectin-3 as New Binding Partners
Gallardo-Vara E, Ruiz-Llorente L, Casado-Vela J, Ruiz-Rodríguez MJ, López-Andrés N, Pattnaik AK, Quintanilla M, Bernabeu C. Endoglin Protein Interactome Profiling Identifies TRIM21 and Galectin-3 as New Binding Partners. Cells. 2019 Sep 13;8(9):1082. doi: 10.3390/cells8091082. PMID: 31540324; PMCID: PMC6769930.
Abstract
Endoglin is a 180-kDa glycoprotein receptor primarily expressed by the vascular endothelium and involved in cardiovascular disease and cancer. Heterozygous mutations in the endoglin gene (ENG) cause hereditary hemorrhagic telangiectasia type 1, a vascular disease that presents with nasal and gastrointestinal bleeding, skin and mucosa telangiectases, and arteriovenous malformations in internal organs. A circulating form of endoglin (alias soluble endoglin, sEng), proteolytically released from the membrane-bound protein, has been observed in several inflammation-related pathological conditions and appears to contribute to endothelial dysfunction and cancer development through unknown mechanisms. Membrane-bound endoglin is an auxiliary component of the TGF-β receptor complex and the extracellular region of endoglin has been shown to interact with types I and II TGF-β receptors, as well as with BMP9 and BMP10 ligands, both members of the TGF-β family. To search for novel protein interactors, we screened a microarray containing over 9000 unique human proteins using recombinant sEng as bait. We find that sEng binds with high affinity, at least, to 22 new proteins. Among these, we validated the interaction of endoglin with galectin-3, a secreted member of the lectin family with capacity to bind membrane glycoproteins, and with tripartite motif-containing protein 21 (TRIM21), an E3 ubiquitin-protein ligase. Using human endothelial cells and Chinese hamster ovary cells, we showed that endoglin co-immunoprecipitates and co-localizes with galectin-3 or TRIM21. These results open new research avenues on endoglin function and regulation.
Endoglin is an auxiliary TGF-β co-receptor predominantly expressed in endothelial cells, which is involved in vascular development, repair, homeostasis, and disease [1,2,3,4]. Heterozygous mutations in the human ENDOGLIN gene (ENG) cause hereditary hemorrhagic telangiectasia (HHT) type 1, a vascular disease associated with nasal and gastrointestinal bleeds, telangiectases on skin and mucosa and arteriovenous malformations in the lung, liver, and brain [4,5,6]. The key role of endoglin in the vasculature is also illustrated by the fact that endoglin-KO mice die in utero due to defects in the vascular system [7]. Endoglin expression is markedly upregulated in proliferating endothelial cells involved in active angiogenesis, including the solid tumor neovasculature [8,9]. For this reason, endoglin has become a promising target for the antiangiogenic treatment of cancer [10,11,12]. Endoglin is also expressed in cancer cells where it can behave as both a tumor suppressor in prostate, breast, esophageal, and skin carcinomas [13,14,15,16] and a promoter of malignancy in melanoma and Ewing’s sarcoma [17]. Ectodomain shedding of membrane-bound endoglin may lead to a circulating form of the protein, also known as soluble endoglin (sEng) [18,19,20]. Increased levels of sEng have been found in several vascular-related pathologies, including preeclampsia, a disease of high prevalence in pregnant women which, if left untreated, can lead to serious and even fatal complications for both mother and baby [2,18,19,21]. Interestingly, several lines of evidence support a pathogenic role of sEng in the vascular system, including endothelial dysfunction, antiangiogenic activity, increased vascular permeability, inflammation-associated leukocyte adhesion and transmigration, and hypertension [18,22,23,24,25,26,27]. Because of its key role in vascular pathology, a large number of studies have addressed the structure and function of endoglin at the molecular level, in order to better understand its mechanism of action.
Galectin-3 Interacts with Endoglin in Cells
Galectin-3 is a secreted member of the lectin family with the capacity to bind membrane glycoproteins like endoglin and is involved in the pathogenesis of many human diseases [52]. We confirmed the protein screen data for galectin-3, as evidenced by two-way co-immunoprecipitation of endoglin and galectin-3 upon co-transfection in CHO-K1 cells. As shown in Figure 1A, galectin-3 and endoglin were efficiently transfected, as demonstrated by Western blot analysis in total cell extracts. No background levels of endoglin were observed in control cells transfected with the empty vector (Ø). By contrast, galectin-3 could be detected in all samples but, as expected, showed an increased signal in cells transfected with the galectin-3 expression vector. Co-immunoprecipitation studies of these cell lysates showed that galectin-3 was present in endoglin immunoprecipitates (Figure 1B). Conversely, endoglin was also detected in galectin-3 immunoprecipitates (Figure 1C).
Figure 1. Protein–protein association between galectin-3 and endoglin. (A–C). Co-immunoprecipitation of galectin-3 and endoglin. CHO-K1 cells were transiently transfected with pcEXV-Ø (Ø), pcEXV–HA–EngFL (Eng) and pcDNA3.1–Gal-3 (Gal3) expression vectors. (A) Total cell lysates (TCL) were analyzed by SDS-PAGE under reducing conditions, followed by Western blot (WB) analysis using specific antibodies to endoglin, galectin-3 and β-actin (loading control). Cell lysates were subjected to immunoprecipitation (IP) with anti-endoglin (B) or anti-galectin-3 (C) antibodies, followed by SDS-PAGE under reducing conditions and WB analysis with anti-endoglin or anti-galectin-3 antibodies, as indicated. Negative controls with an IgG2b (B) and IgG1 (C) were included. (D) Protein-protein interactions between galectin-3 and endoglin using Bio-layer interferometry (BLItz). The Ni–NTA biosensors tips were loaded with 7.3 µM recombinant human galectin-3/6xHis at the C-terminus (LGALS3), and protein binding was measured against 0.1% BSA in PBS (negative control) or 4.1 µM soluble endoglin (sEng). Kinetic sensorgrams were obtained using a single channel ForteBioBLItzTM instrument.
Figure 2.Galectin-3 and endoglin co-localize in human endothelial cells. Human umbilical vein-derived endothelial cell (HUVEC) monolayers were fixed with paraformaldehyde, permeabilized with Triton X-100, incubated with the mouse mAb P4A4 anti-endoglin, washed, and incubated with a rabbit polyclonal anti-galectin-3 antibody (PA5-34819). Galectin-3 and endoglin were detected by immunofluorescence upon incubation with Alexa 647 goat anti-rabbit IgG (red staining) and Alexa 488 goat anti-mouse IgG (green staining) secondary antibodies, respectively. (A) Single staining of galectin-3 (red) and endoglin (green) at the indicated magnifications. (B) Merge images plus DAPI (nuclear staining in blue) show co-localization of galectin-3 and endoglin (yellow color). Representative images of five different experiments are shown.
Endoglin associates with the cullin-type E3 ligase TRIM21
Figure 3.Protein–protein association between TRIM21 and endoglin. (A–E) Co-immunoprecipitation of TRIM21 and endoglin. A,B. HUVEC monolayers were lysed and total cell lysates (TCL) were subjected to SDS-PAGE under reducing (for TRIM21 detection) or nonreducing (for endoglin detection) conditions, followed by Western blot (WB) analysis using antibodies to endoglin, TRIM21 or β-actin (A). HUVECs lysates were subjected to immunoprecipitation (IP) with anti-TRIM21 or negative control antibodies, followed by WB analysis with anti-endoglin (B). C,D. CHO-K1 cells were transiently transfected with pDisplay–HA–Mock (Ø), pDisplay–HA–EngFL (E) or pcDNA3.1–HA–hTRIM21 (T) expression vectors, as indicated. Total cell lysates (TCL) were subjected to SDS-PAGE under nonreducing conditions and WB analysis using specific antibodies to endoglin, TRIM21, and β-actin (C). Cell lysates were subjected to immunoprecipitation (IP) with anti-TRIM21 or anti-endoglin antibodies, followed by SDS-PAGE under reducing (upper panel) or nonreducing (lower panel) conditions and WB analysis with anti-TRIM21 or anti-endoglin antibodies. Negative controls of appropriate IgG were included (D). E. CHO-K1 cells were transiently transfected with pcDNA3.1–HA–hTRIM21 and pDisplay–HA–Mock (Ø), pDisplay–HA–EngFL (FL; full-length), pDisplay–HA–EngEC (EC; cytoplasmic-less) or pDisplay–HA–EngTMEC (TMEC; cytoplasmic-less) expression vectors, as indicated. Cell lysates were subjected to immunoprecipitation with anti-TRIM21, followed by SDS-PAGE under reducing conditions and WB analysis with anti-endoglin antibodies, as indicated. The asterisk indicates the presence of a nonspecific band. Mr, molecular reference; Eng, endoglin; TRIM, TRIM21. (F) Protein–protein interactions between TRIM21 and endoglin using Bio-layer interferometry (BLItz). The Ni–NTA biosensors tips were loaded with 5.4 µM recombinant human TRIM21/6xHis at the N-terminus (R052), and protein binding was measured against 0.1% BSA in PBS (negative control) or 4.1 µM soluble endoglin (sEng). Kinetic sensorgrams were obtained using a single channel ForteBioBLItzTM instrument.
Table 1. Human protein-array analysis of endoglin interactors1.
1 Microarrays containing over 9000 unique human proteins were screened using recombinant sEng as a probe. Protein interactors showing the highest scores (Z-score ≥2.0) are listed. GeneBank (https://www.ncbi.nlm.nih.gov/genbank/) and UniProtKB (https://www.uniprot.org/help/uniprotkb) accession numbers are indicated with a yellow or green background, respectively. The cellular compartment of each protein was obtained from the UniProtKB webpage. Proteins selected for further studies (TRIM21 and galectin-3) are indicated in bold type with blue background.
Note: the following are from NCBI Genbank and Genecards on TRIM21
This gene encodes a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The encoded protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. RoSSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Alternatively spliced transcript variants for this gene have been described but the full-length nature of only one has been determined. [provided by RefSeq, Jul 2008]
Expression
Ubiquitous expression in spleen (RPKM 15.5), appendix (RPKM 13.2) and 24 other tissues See more
This gene encodes a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The encoded protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. RoSSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Alternatively spliced transcript variants for this gene have been described but the full-length nature of only one has been determined. [provided by RefSeq, Jul 2008]
E3 ubiquitin-protein ligase whose activity is dependent on E2 enzymes, UBE2D1, UBE2D2, UBE2E1 and UBE2E2. Forms a ubiquitin ligase complex in cooperation with the E2 UBE2D2 that is used not only for the ubiquitination of USP4 and IKBKB but also for its self-ubiquitination. Component of cullin-RING-based SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complexes such as SCF(SKP2)-like complexes. A TRIM21-containing SCF(SKP2)-like complex is shown to mediate ubiquitination of CDKN1B (‘Thr-187’ phosphorylated-form), thereby promoting its degradation by the proteasome. Monoubiquitinates IKBKB that will negatively regulates Tax-induced NF-kappa-B signaling. Negatively regulates IFN-beta production post-pathogen recognition by polyubiquitin-mediated degradation of IRF3. Mediates the ubiquitin-mediated proteasomal degradation of IgG1 heavy chain, which is linked to the VCP-mediated ER-associated degradation (ERAD) pathway. Promotes IRF8 ubiquitination, which enhanced the ability of IRF8 to stimulate cytokine genes transcription in macrophages. Plays a role in the regulation of the cell cycle progression. Enhances the decapping activity of DCP2. Exists as a ribonucleoprotein particle present in all mammalian cells studied and composed of a single polypeptide and one of four small RNA molecules. At least two isoforms are present in nucleated and red blood cells, and tissue specific differences in RO/SSA proteins have been identified. The common feature of these proteins is their ability to bind HY RNAs.2. Involved in the regulation of innate immunity and the inflammatory response in response to IFNG/IFN-gamma. Organizes autophagic machinery by serving as a platform for the assembly of ULK1, Beclin 1/BECN1 and ATG8 family members and recognizes specific autophagy targets, thus coordinating target recognition with assembly of the autophagic apparatus and initiation of autophagy. Acts as an autophagy receptor for the degradation of IRF3, hence attenuating type I interferon (IFN)-dependent immune responses (PubMed:26347139, 16297862, 16316627, 16472766, 16880511, 18022694, 18361920, 18641315, 18845142, 19675099). Represses the innate antiviral response by facilitating the formation of the NMI-IFI35 complex through ‘Lys-63’-linked ubiquitination of NMI (PubMed:26342464). ( RO52_HUMAN,P19474 )
Molecular function for TRIM21 Gene according to UniProtKB/Swiss-Prot
Function:
E3 ubiquitin-protein ligase whose activity is dependent on E2 enzymes, UBE2D1, UBE2D2, UBE2E1 and UBE2E2. Forms a ubiquitin ligase complex in cooperation with the E2 UBE2D2 that is used not only for the ubiquitination of USP4 and IKBKB but also for its self-ubiquitination. Component of cullin-RING-based SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complexes such as SCF(SKP2)-like complexes. A TRIM21-containing SCF(SKP2)-like complex is shown to mediate ubiquitination of CDKN1B (‘Thr-187’ phosphorylated-form), thereby promoting its degradation by the proteasome. Monoubiquitinates IKBKB that will negatively regulates Tax-induced NF-kappa-B signaling. Negatively regulates IFN-beta production post-pathogen recognition by polyubiquitin-mediated degradation of IRF3. Mediates the ubiquitin-mediated proteasomal degradation of IgG1 heavy chain, which is linked to the VCP-mediated ER-associated degradation (ERAD) pathway. Promotes IRF8 ubiquitination, which enhanced the ability of IRF8 to stimulate cytokine genes transcription in macrophages. Plays a role in the regulation of the cell cycle progression.
Other Articles in this Open Access Scientific Journal on Galectins and Proteosome Include
JenaValve, a California-based transcatheter aortic valve replacement (TAVR) company, has found considerable success in Europe with its Trilogy Heart Valve System for high-risk patients with symptomatic, severe aortic regurgitation (AR), gaining CE mark approval for the device in May 2021. The company has been working toward gaining U.S. Food and Drug Administration (FDA) approval for Trilogy, and recent data have suggested that moment could come sooner than later.
JenaValve shared its excitement about the acquisition on social media, saying its employees remain focused on developing “the world’s first transcatheter heart valve technology uniquely designed for patients with AR.”
“Together with Edwards, the world’s leader in TAVR, we are now closer to addressing the global unmet need,” the company wrote.
An 82-year-old man presenting with severe symptomatic tricuspid regurgitation (TR) and right heart failure (RHF).
Expert Opinion: The Voice of Dr. Justin D. Pearlman, MD, PhD, FACC
The TricValve addresses the problem of severe ìncompetance of the tricuspid valve with a relatively simple procedure.
Instead of the challenge of replacing the defective valve, a catheter procedùre places valves at the two venous intake locations, the superior and ìnferior vena cava. A valve at the superior vena cava entrance to the right atrium occurs occasionally in nature, but is usually absent or fenestrated, covering the medial end if the crista supraventricularis.
A similar termed valve is occasionally found in nature on the inferior vena cava. These supernumerary valves can arrest back flow of pressure and volume from the right atrium to the upper and lower venous systems, and alleviate in particular congestion of the liver.
Normally the right atrial pressure is low, in which case this would offer no significant advantage for reproductive success natural selection to offset potential interference with blood flow into the right atrium that might promote thrombosis [Folia Morphology Morphology 66(4):303-6, MRuso].
However, in a setting of right heart failure, such as occurs from pulmonary hypertension, the tricuspid valve often becomes incompetent, and placement of the pair of vena cava valves can alleviate upstream consequences, albeit at the cost of risk of thrombosis and future impediment to other future procedures such as ablation of supraventricular arrhythmia.
The vena cava valves placed by catheter at the Cleveland Clinic helped an 80 year old man alleviate his pressing issue of hepatic congestion. Unlike a replacement tricuspid valve this procedure does not alleviate high pressures dilatìng the right atrium. Instead, it can worsen that problem.
The CLASP II TR trial is investigating the Edwards PASCAL transcatheter repair system [CLASP II TR, Edwards Lifesciences Corp, NIH NCT 0497145]
Survival data for surgìcal tricuspid valve replacements reported 37+-10 percent ten year survival, with average all cause survival of just 8.5 years [Z HIscan, Euro J CT Surgery 32(2) Aug 2007]. None-the‐less, comparison of patients with vs without intervention for incompetance of the trìcuspid valve favored mechanical intervention [G Dreyfus Ann Thorac Surg 49:706-11,1990, D Adams, JACC 65:1931-8, 2015]. Time will tell which interventìon will prevail, and when these catheter alternatives to open chest surgery should be deployed.
Rishi Puri, MD, PhD, an interventional cardiologist with Cleveland Clinic, and Samir Kapadia, MD, chair of cardiovascular medicine at Cleveland Clinic, performed the procedure. Puri has years of experience with the TricValve system, participating in a thorough analysis of its safety and effectiveness in 2021.
The TricValve system features two biological valves designed to be implanted via femoral vein access into the patient’s superior vena cava and inferior vena cava. This allows a therapy without impacting the patient’s native tricuspid valve. It is available in multiple sizes, allowing cardiologists to choose the best option for each individual patient.
Cleveland Clinic’s statement detailing the successful procedure notes that patients with severe TR and RHF have typically had limited treatment options. Tricuspid valve surgery is associated with significant risks, for instance, and prescribing diuretics is problematic when the patient also presents with kidney problems.
“TricValve can potentially provide an effective and low-risk solution for many patients who currently have no treatment options,” Puri said, adding that the workflow is quite similar to transcatheter aortic valve replacement.
The TricValve Transcatheter Bicaval Valves System was developed by P+F Products + Features GmbH, a healthcare technology company based out of Vienna, Austria. The solution was granted the FDA’s Breakthrough Device designation in December 2020, but it has still not gained full FDA approval.
This procedure was completed under a compassionate-use clearance from the FDA.
Mechanistic link between SARS-CoV-2 infection and increased risk of stroke using 3D printed models and human endothelial cells
Reporter: Adina Hazan, PhD
Kaneko, et al. from UCLA aimed to explore why SARS-CoV-2 infection is associated with an increased rate of cerebrovascular events, including
ischemic stroke and
intracerebral hemorrhage
While some suggested mechanisms include an overall systemic inflammatory response including increasing circulating cytokines and leading to a prothrombotic state, this may be only a partial answer. A SARS-CoV-2 specific mechanism could be likely, considering that both angiotensin-converting enzyme-2 (ACE2), the receptor necessary for SARS-CoV-2 to gain entry into the cell, and SARS-CoV-2 RNA have been reportedly detected in the human brain postmortem.
One of the difficulties in studying vasculature mechanisms is that the inherent 3D shape and blood flow subject this tissue to different stressors, such as flow, that could be critically relevant during inflammation. To accurately study the effect of SARS-CoV-2 on the vasculature of the brain, the team generated 3D models of the human middle cerebral artery during intracranial artery stenosis using data from CT (computed tomography) angiography. This data was then exported with important factors included such as
shear stress during perfusion,
streamlines, and
flow velocity to be used to fabricate 3D models.
These tubes were then coated with endothelial cells isolated and sorted from normal human brain tissue resected during surgery. In doing so, this model could closely mimic the cellular response of the vasculature of the human brain.
Surprisingly, without this 3D tube, human derived brain endothelial cells displayed very little expression of ACE2 or, TMPRSS2 (transmembrane protease 2), a necessary cofactor for SARS-COV-2 viral entry.
Interestingly,
horizontal shear stress increased the expression of ACE2 and
increased the binding of spike protein to ACE2, especially within the stenotic portion of the 3D model.
By exposing the endothelial cells to liposomes expressing the SARS-CoV-2 spike protein, they also were able to explore key upregulated genes in the exposed cells, in which they found that
“binding of SARS-CoV-2 S protein triggered 83 unique genes in human brain endothelial cells”.
This included many inflammatory signals, some of which have been previously described as associated with SARS-COV-2, and others whose effects are unknown. This may provide an important foundation for exploring potential therapeutic targets in patients susceptible to cerebrovascular events.
Overall, this study shows important links between the
mechanisms of SARS-CoV-2 and the
increase in ischemic events in these patients. It also has important implications for
treatment for SARS-CoV-2, as high blood pressure and atherosclerosis may be increasing ACE2 expression in patients, providing the entry port for viral particles into brain endothelia.
The cardiovascular team at SSM Health Cardinal Glennon Children’s Hospital found a solution for better surgical planning using 3D printing. As a pediatric center, Glennon Children’s Hospital deals with the most complex patients, which requires surgeries within days or weeks of birth. According to the center, one of the pediatric patients was an infant diagnosed in utero via fetal ultrasound with an unusual form of switch of great arteries. Deoxygenated blue blood entered the right atrium which connected to the left ventricle, then to the aorta and the oxygenated red blood entered the left atrium which connects to the right ventricle and then to the pulmonary artery. The pediatric patients had a very large ventricular septal defect connecting both ventricles and severe narrowing between the left ventricle and the aorta.
It is obvious that the patient was fairly blue as deoxygenated blood was directed toward the aorta. The balloon atrial septostomy made in the first few days of life. Yet, the tachycardia persisted. The surgical team from SSM Health Cardinal Glennon Children’s Hospital, led by Charles Huddleston, MD used 3D printing to identify the anatomy of the patient clearly and provided them with the ability to repair the mitral valve. It seems that the neonatal atrial switch appeared to be the best plan, even if the operation proved challenging.
The team knew that they could go into the procedure knowing that the tissue can be safely removed without damage to the mitral valve. The team was able to show that the 3D model was essential in determining the optimal surgical approach and with the help of the 3D printed heart model, the neonatal atrial switch, the VSD closure and the subaortic stenosis resection was performed effectively on a 20-day infant. The surgery allowed the mitral valve function to remain intact. The pediatric patient cardiac function improved gradually and is expected to have an excellent recovery.
Artificial Intelligence and Cardiovascular Disease
Reporter and Curator: Dr. Sudipta Saha, Ph.D.
3.3.18 Artificial Intelligence and Cardiovascular Disease, Volume 2 (Volume Two: Latest in Genomics Methodologies for Therapeutics: Gene Editing, NGS and BioInformatics, Simulations and the Genome Ontology), Part 2: CRISPR for Gene Editing and DNA Repair
Cardiology is a vast field that focuses on a large number of diseases specifically dealing with the heart, the circulatory system, and its functions. As such, similar symptomatologies and diagnostic features may be present in an individual, making it difficult for a doctor to easily isolate the actual heart-related problem. Consequently, the use of artificial intelligence aims to relieve doctors from this hurdle and extend better quality to patients. Results of screening tests such as echocardiograms, MRIs, or CT scans have long been proposed to be analyzed using more advanced techniques in the field of technology. As such, while artificial intelligence is not yet widely-used in clinical practice, it is seen as the future of healthcare.
The continuous development of the technological sector has enabled the industry to merge with medicine in order to create new integrated, reliable, and efficient methods of providing quality health care. One of the ongoing trends in cardiology at present is the proposed utilization of artificial intelligence (AI) in augmenting and extending the effectiveness of the cardiologist. This is because AI or machine-learning would allow for an accurate measure of patient functioning and diagnosis from the beginning up to the end of the therapeutic process. In particular, the use of artificial intelligence in cardiology aims to focus on research and development, clinical practice, and population health. Created to be an all-in-one mechanism in cardiac healthcare, AI technologies incorporate complex algorithms in determining relevant steps needed for a successful diagnosis and treatment. The role of artificial intelligence specifically extends to the identification of novel drug therapies, disease stratification or statistics, continuous remote monitoring and diagnostics, integration of multi-omic data, and extension of physician effectivity and efficiency.
Artificial intelligence – specifically a branch of it called machine learning – is being used in medicine to help with diagnosis. Computers might, for example, be better at interpreting heart scans. Computers can be ‘trained’ to make these predictions. This is done by feeding the computer information from hundreds or thousands of patients, plus instructions (an algorithm) on how to use that information. This information is heart scans, genetic and other test results, and how long each patient survived. These scans are in exquisite detail and the computer may be able to spot differences that are beyond human perception. It can also combine information from many different tests to give as accurate a picture as possible. The computer starts to work out which factors affected the patients’ outlook, so it can make predictions about other patients.
In current medical practice, doctors will use risk scores to make treatment decisions for their cardiac patients. These are based on a series of variables like weight, age and lifestyle. However, they do not always have the desired levels of accuracy. A particular example of the use of artificial examination in cardiology is the experimental study on heart disease patients, published in 2017. The researchers utilized cardiac MRI-based algorithms coupled with a 3D systolic cardiac motion pattern to accurately predict the health outcomes of patients with pulmonary hypertension. The experiment proved to be successful, with the technology being able to pick-up 30,000 points within the heart activity of 250 patients. With the success of the aforementioned study, as well as the promise of other researches on artificial intelligence, cardiology is seemingly moving towards a more technological practice.
One study was conducted in Finland where researchers enrolled 950 patients complaining of chest pain, who underwent the centre’s usual scanning protocol to check for coronary artery disease. Their outcomes were tracked for six years following their initial scans, over the course of which 24 of the patients had heart attacks and 49 died from all causes. The patients first underwent a coronary computed tomography angiography (CCTA) scan, which yielded 58 pieces of data on the presence of coronary plaque, vessel narrowing and calcification. Patients whose scans were suggestive of disease underwent a positron emission tomography (PET) scan which produced 17 variables on blood flow. Ten clinical variables were also obtained from medical records including sex, age, smoking status and diabetes. These 85 variables were then entered into an artificial intelligence (AI) programme called LogitBoost. The AI repeatedly analysed the imaging variables, and was able to learn how the imaging data interacted and identify the patterns which preceded death and heart attack with over 90% accuracy. The predictive performance using the ten clinical variables alone was modest, with an accuracy of 90%. When PET scan data was added, accuracy increased to 92.5%. The predictive performance increased significantly when CCTA scan data was added to clinical and PET data, with accuracy of 95.4%.
Another study findings showed that applying artificial intelligence (AI) to the electrocardiogram (ECG) enables early detection of left ventricular dysfunction and can identify individuals at increased risk for its development in the future. Asymptomatic left ventricular dysfunction (ALVD) is characterised by the presence of a weak heart pump with a risk of overt heart failure. It is present in three to six percent of the general population and is associated with reduced quality of life and longevity. However, it is treatable when found. Currently, there is no inexpensive, noninvasive, painless screening tool for ALVD available for diagnostic use. When tested on an independent set of 52,870 patients, the network model yielded values for the area under the curve, sensitivity, specificity, and accuracy of 0.93, 86.3 percent, 85.7 percent, and 85.7 percent, respectively. Furthermore, in patients without ventricular dysfunction, those with a positive AI screen were at four times the risk of developing future ventricular dysfunction compared with those with a negative screen.
In recent years, the analysis of big data database combined with computer deep learning has gradually played an important role in biomedical technology. For a large number of medical record data analysis, image analysis, single nucleotide polymorphism difference analysis, etc., all relevant research on the development and application of artificial intelligence can be observed extensively. For clinical indication, patients may receive a variety of cardiovascular routine examination and treatments, such as: cardiac ultrasound, multi-path ECG, cardiovascular and peripheral angiography, intravascular ultrasound and optical coherence tomography, electrical physiology, etc. By using artificial intelligence deep learning system, the investigators hope to not only improve the diagnostic rate and also gain more accurately predict the patient’s recovery, improve medical quality in the near future.
The primary issue about using artificial intelligence in cardiology, or in any field of medicine for that matter, is the ethical issues that it brings about. Physicians and healthcare professionals prior to their practice swear to the Hippocratic Oath—a promise to do their best for the welfare and betterment of their patients. Many physicians have argued that the use of artificial intelligence in medicine breaks the Hippocratic Oath since patients are technically left under the care of machines than of doctors. Furthermore, as machines may also malfunction, the safety of patients is also on the line at all times. As such, while medical practitioners see the promise of artificial technology, they are also heavily constricted about its use, safety, and appropriateness in medical practice.
Issues and challenges faced by technological innovations in cardiology are overpowered by current researches aiming to make artificial intelligence easily accessible and available for all. With that in mind, various projects are currently under study. For example, the use of wearable AI technology aims to develop a mechanism by which patients and doctors could easily access and monitor cardiac activity remotely. An ideal instrument for monitoring, wearable AI technology ensures real-time updates, monitoring, and evaluation. Another direction of cardiology in AI technology is the use of technology to record and validate empirical data to further analyze symptomatology, biomarkers, and treatment effectiveness. With AI technology, researchers in cardiology are aiming to simplify and expand the scope of knowledge on the field for better patient care and treatment outcomes.
Recent research from University of Alberta is looking at the role of fibrinogen, the substrate of thrombin in regulating a natural defense mechanism in the body. Fibrinogen is a well-known protein that is essential for wound healing and blood clotting in the body. Levels of fibrinogen increase in inflammatory states as part of the acute-phase response.
However, daily variation in plasma fibrinogen levels weakens its potential as a biomarker of cardiovascular risk. The discovery is expected to contribute to enhanced diagnosis and treatments for patients in a variety of diseases ranging from inflammation, to heart failure, to cancer.
Yet, a study published in Scientific Reports in March 2019 show that fibrinogen can also be a natural inhibitor of an enzyme named MMP2, which is important for normal organ development and repair. The researchers believe an essential function of fibrinogen is to allow or disallow the enzyme to carry out its normal functions. Nevertheless, high levels of fibrinogen may disproportionately inhibit MMP2, that could result in arthritic and cardiac disorders.
The researcher highlights the inner workings of the MMP family of enzymes by having a greater understanding of how MMPs are regulated. They hypothesize that abnormal MMP2 activity could be an unwelcome side effect of common medications such as the cholesterol-lowering drugs and the antibiotic doxycycline, both of which are known to inhibit MMPs. They also emphasize that future therapeutic developments must strike a balance between the levels of MMPs and their inhibitors, such as fibrinogen, so that net MMP activity in the body remains at nearly normal levels.