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Archive for the ‘Population Health Management, Nutrition and Phytochemistry’ Category


Thymic Dysfunction and Atrophy in COVID-19 Disease Complicated by Inflammation, Malnutrition and Cachexia

Reporter: Aviva Lev-Ari, PhD, RN

Kate Chiang

Charak Foundation; Applied Medical Technologies LLC

Kamyar Kalantar-Zadeh

University of California Irvine

Ajay Gupta

University of California Irvine

Date Written: July 13, 2020

Abstract

The current COVID-19 pandemic sweeping across developing countries is putting millions at risk of protein-energy malnutrition by pushing them into poverty and disrupting the global food supply chain. COVID-19 disease and protein-energy malnutrition are both known to cause immune dysfunction. The objective of this review is to highlight the known pathogenetic mechanisms underlying immune dysfunction in COVID-19 disease and malnutrition, and thereby identify preventive and therapeutic interventions that would help limit and contain the global health impact of this pandemic. Severe COVID-19 disease is characterized by dysregulation of myeloid compartments and lymphopenia. Lymphopenia is often protracted and outlasts the cytokine storm, suggesting underlying thymic dysfunction or involution. The thymus is considered a barometer of malnutrition, and leptin deficiency induced by protein-energy malnutrition can lead to thymic dysfunction and atrophy. Immune dysfunction in COVID-19 disease and malnutrition may be further increased by comorbidities including zinc and vitamin deficiencies, hyperinflammation, and stress. Thymic dysfunction or involution, especially in children, can potentially slow the recovery from COVID-19 disease and increase the risk of other infections. National governments and international organizations including WHO, World Food Program, and UNICEF should institute measures to ensure provision of food including micronutrients for the poor, thereby mitigating the health impact of the COVID-19 pandemic, especially amongst children in developing countries.

 

Note: Conflict of Interest: AG has filed provisional patents for use of Ramatroban as an immunotherapy to treat COVID-19 infection. (Gupta, A. Use of Ramatroban as a therapeutic agent for prevention and treatment of viral infections including COVID-Application no. 63/003,286 filed on March 31, 2020; and Gupta A. Use of a DP2 antagonist such as Ramatroban as a therapeutic agent for treatment of adults with viral infection including COVID-19 Provisional Patent Application no. 63/005,205 filed on April 3, 2020). Other authors have not declared conflict of interest.

Funding: None to declare

Keywords: COVID-19, protein-calorie malnutrition, thymic atrophy, inflammation, zinc, cachexia, lymphopenia, leptin, stress, glucocorticoids

 Suggested Citation

Chiang, Kate and Kalantar-Zadeh, Kamyar and Gupta, Ajay, Thymic Dysfunction and Atrophy in COVID-19 Disease Complicated by Inflammation, Malnutrition and Cachexia (July 13, 2020). Available at SSRN: https://ssrn.com/abstract=3649836 or http://dx.doi.org/10.2139/ssrn.3649836

Kate Chiang

Charak Foundation ( email )

12551 Downey Ave
Downey, CA 90242
United States
5627020617 (Phone)

Applied Medical Technologies LLC ( email )

2505 Seascape Drive
Las Vegas, NV NV 89128
United States
5624126259 (Phone)
89128 (Fax)

Kamyar Kalantar-Zadeh

University of California Irvine ( email )

Division of Nephrology, University of California I
101 City Drive South, City Tower, Suite 400-ZOT;40
Orange, CA California 92868-3217
United States
7144565142 (Phone)

Ajay Gupta (Contact Author)

University of California Irvine ( email )

Division of Nephrology, University of California I
101 City Drive South, City Tower, Suite 400-ZOT;40
Orange, CA California 92868-3217
United States
5624197029 (Phone)
92868-3217 (Fax)

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via Key Immune System Genes Identified to Explain High COVID Deaths and Spread in Northern Italy Versus Fewer Cases and Deaths in the South

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From Cell Press:  New Insights on the D614G Strain of COVID: Will a New Mutated Strain Delay Vaccine Development?

Reporter: Stephen J. Williams, PhD

Two recent articles in Cell Press, both peer reviewed, discuss the emergence and potential dominance of a new mutated strain of COVID-19, in which the spike protein harbors a D614G mutation.

In the first article “Making Sense of Mutation: What D614G means for the COVID-19 pandemic Remains Unclear”[1] , authors Drs. Nathan Grubaugh, William Hanage, and Angela Rasmussen discuss the recent findings by Korber et al. 2020 [2] which describe the potential increases in infectivity and mortality of this new mutant compared to the parent strain of SARS-CoV2.  For completeness sake I will post this article as to not defer from their interpretations of this important paper by Korber and to offer some counter opinion to some articles which have surfaced this morning in the news.

Making sense of mutation: what D614G means for the COVID-19 pandemic remains unclear

 

Nathan D. Grubaugh1 *, William P. Hanage2 *, Angela L. Rasmussen3 * 1Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA 2Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA 02115, USA 3Center for Infection and Immunity, Columbia Mailman School of Public Health, New York, NY 10032, USA Correspondence: grubaughlab@gmail.com

 

Abstract: Korber et al. (2020) found that a SARS-CoV-2 variant in the spike protein, D614G, rapidly became dominant around the world. While clinical and in vitro data suggest that D614G changes the virus phenotype, the impact of the mutation on transmission, disease, and vaccine and therapeutic development are largely unknown.

Introduction: Following the emergence of SARS-CoV-2 in China in late 2019, and the rapid expansion of the COVID19 pandemic in 2020, questions about viral evolution have come tumbling after. Did SARS-CoV-2 evolve to become better adapted to humans? More infectious or transmissible? More deadly? Virus mutations can rise in frequency due to natural selection, random genetic drift, or features of recent epidemiology. As these forces can work in tandem, it’s often hard to differentiate when a virus mutation becomes common through fitness or by chance. It is even harder to determine if a single mutation will change the outcome of an infection, or a pandemic. The new study by Korber et al. (2020) sits at the heart of this debate. They present compelling data that an amino acid change in the virus’ spike protein, D614G, emerged early during the pandemic, and viruses containing G614 are now dominant in many places around the world. The crucial questions are whether this is the result of natural selection, and what it means for the COVID-19 pandemic. For viruses like SARS-CoV-2 transmission really is everything – if they don’t get into another host their lineage ends. Korber et al. (2020) hypothesized that the rapid spread of G614 was because it is more infectious than D614. In support of their hypothesis, the authors provided evidence that clinical samples from G614 infections have a higher levels of viral RNA, and produced higher titers in pseudoviruses from in vitro experiments; results that now seem to be corroborated by others [e.g. (Hu et al., 2020; Wagner et al., 2020)]. Still, these data do not prove that G614 is more infectious or transmissible than viruses containing D614. And because of that, many questions remain on the potential impacts, if any, that D614G has on the COVID-19 pandemic.

The authors note that this new G614 variant has become the predominant form over the whole world however in China the predominant form is still the D614 form.  As they state

“over the period that G614 became the global majority variant, the number of introductions from China where D614 was still dominant were declining, while those from Europe climbed. This alone might explain the apparent success of G614.”

Grubaugh et al. feel there is not enough evidence that infection with this new variant will lead to higher mortality.  Both Korber et al. and the Seattle study (Wagner et al) did not find that the higher viral load of this variant led to a difference in hospitalizations so apparently each variant might be equally as morbid.

In addition, Grubaugh et al. believe this variant would not have much affect on vaccine development as, even though the mutation lies within the spike protein, D614G is not in the receptor binding domain of the spike protein.  Korber suggest that there may be changes in glycosylation however these experiments will need to be performed.  In addition, antibodies from either D614 or G614 variant infected patients could cross neutralize.

 

Conclusions: While there has already been much breathless commentary on what this mutation means for the COVID19 pandemic, the global expansion of G614 whether through natural selection or chance means that this variant now is the pandemic. As a result its properties matter. It is clear from the in vitro and clinical data that G614 has a distinct phenotype, but whether this is the result of bonafide adaptation to human ACE2, whether it increases transmissibility, or will have a notable effect, is not clear. The work by Korber et al. (2020) provides an early base for more extensive epidemiological, in vivo experimental, and diverse clinical investigations to fill in the many critical gaps in how D614G impacts the pandemic.

The link to the Korber Cell paper is here: https://www.cell.com/cell/fulltext/S0092-8674(20)30820-5

Tracking changes in SARS-CoV-2 Spike: evidence that D614G increases infectivity of the COVID-19 virus

DOI: https://doi.org/10.1016/j.cell.2020.06.043

Keypoints

  • The consistent increase of G614 at regional levels may indicate a fitness advantage

 

  • G614 is associated with lower RT PCR Ct’s, suggestive of higher viral loads in patients

 

  • The G614 variant grows to higher titers as pseudotyped virions

Summary

A SARS-CoV-2 variant carrying the Spike protein amino acid change D614G has become the most prevalent form in the global pandemic. Dynamic tracking of variant frequencies revealed a recurrent pattern of G614 increase at multiple geographic levels: national, regional and municipal. The shift occurred even in local epidemics where the original D614 form was well established prior to the introduction of the G614 variant. The consistency of this pattern was highly statistically significant, suggesting that the G614 variant may have a fitness advantage. We found that the G614 variant grows to higher titer as pseudotyped virions. In infected individuals G614 is associated with lower RT-PCR cycle thresholds, suggestive of higher upper respiratory tract viral loads, although not with increased disease severity. These findings illuminate changes important for a mechanistic understanding of the virus, and support continuing surveillance of Spike mutations to aid in the development of immunological interventions.

 

References

  1. Grubaugh, N.D., Hanage, W.P., Rasmussen, A.L., Making sense of mutation: what D614G means for the COVID-19 pandemic remains unclear, Cell (2020), doi: https:// doi.org/10.1016/j.cell.2020.06.040.
  2. Korber, B., Fischer, W.M., Gnanakaran, S., Yoon, H., Theiler, J., Abfalterer, W., Hengartner, N., Giorgi, E.E., Bhattacharya, T., Foley, B., et al. (2020). Tracking changes in SARS-CoV-2 Spike: evidence that D614G increases infectivity of the COVID-19 virus. Cell 182.
  3. Endo, A., Centre for the Mathematical Modelling of Infectious Diseases COVID-19 Working Group, Abbott, S., Kucharski, A.J., and Funk, S. (2020). Estimating the overdispersion in COVID-19 transmission using outbreak sizes outside China. Wellcome Open Res 5, 67.
  4. Hu, J., He, C.-L., Gao, Q.-Z., Zhang, G.-J., Cao, X.-X., Long, Q.-X., Deng, H.-J., Huang, L.-Y., Chen, J., Wang, K., et al. (2020). The D614G mutation of SARS-CoV-2 spike protein enhances viral infectivity and decreases neutralization sensitivity to individual convalescent sera. bioRxiv 2020.06.20.161323.
  5. Wagner, C., Roychoudhury, P., Hadfield, J., Hodcroft, E.B., Lee, J., Moncla, L.H., Müller, N.F., Behrens, C., Huang, M.-L., Mathias, P., et al. (2020). Comparing viral load and clinical outcomes in Washington State across D614G mutation in spike protein of SARS-CoV-2. Https://github.com/blab/ncov-D614G.

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via Special COVID-19 Christopher Magazine

Special COVID-19 Christopher Magazine

Christopher-coverAntonio Giordano, MD, PhD. explains what COVID is and how to contain the infection, pointing also to what will require attention next.

Please see this special release at http://online.fliphtml5.com/qlnw/zgau/#p=1

 

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Responses to the #COVID-19 outbreak from Oncologists, Cancer Societies and the NCI: Important information for cancer patients

Curator: Stephen J. Williams, Ph.D.

UPDATED 3/20/2020

Among the people who are identified at risk of coronovirus 2019 infection and complications of the virus include cancer patients undergoing chemotherapy, who in general, can be immunosuppressed, especially while patients are undergoing their treatment.  This has created anxiety among many cancer patients as well as their care givers and prompted many oncologist professional groups, cancer societies, and cancer centers to formulate some sort of guidelines for both the cancer patients and the oncology professional with respect to limiting the risk of infection to coronavirus (COVID19). 

 

This information will be periodically updated and we are working to get a Live Twitter Feed to bring oncologist and cancer patient advocacy groups together so up to date information can be communicated rapidly.  Please see this page regularly for updates as new information is curated.

IN ADDITION, I will curate a listing of drugs with adverse events of immunosuppression for people who might wonder if the medications they are taking are raising their risk of infections.

Please also see @pharma_BI for updates as well.

Please also see our Coronavirus Portal at https://pharmaceuticalintelligence.com/coronavirus-portal/

For ease of reading information for patients are BOLDED and in RED

ASCO’s Response to COVID-19

From the Cancer Letter: The following is a guest editorial by American Society of Clinical Oncology (ASCO) Executive Vice President and Chief Medical Officer Richard L. Schilsky MD, FACP, FSCT, FASCO. This story is part of The Cancer Letter’s ongoing coverage of COVID-19’s impact on oncology. A full list of our coverage, as well as the latest meeting cancellations, is available here.

 

The worldwide spread of the coronavirus (COVID-19) presents unprecedented challenges to the cancer care delivery system.

Our patients are already dealing with a life-threatening illness and are particularly vulnerable to this viral infection, which can be even more deadly for them. Further, as restrictions in daily movement and social distancing take hold, vulnerable patients may be disconnected from friends, family or other support they need as they manage their cancer.

As providers, we rely on evidence and experience when treating patients but now we face uncertainty. There are limited data to guide us in the specific management of cancer patients confronting COVID-19 and, at present, we have no population-level guidance regarding acceptable or appropriate adjustments of treatment and practice operations that both ensure the best outcome for our patients and protect the safety of our colleagues and staff.

As normal life is dramatically changed, we are all feeling anxious about the extreme economic challenges we face, but these issues are perhaps even more difficult for our patients, many of whom are now facing interruption

As we confront this extraordinary situation, the health and safety of members, staff, and individuals with cancer—in fact, the entire cancer community—is ASCO’s highest priority.

ASCO has been actively monitoring and responding to the pandemic to ensure that accurate information is readily available to clinicians and their patients. Recognizing that this is a rapidly evolving situation and that limited oncology-specific, evidence-based information is available, we are committed to sharing what is known and acknowledging what is unknown so that the most informed decisions can be made.

To help guide oncology professionals as they deal with the impact of coronavirus on both their patients and staff, ASCO has collated questions from its members, posted responses at asco.org and assembled a compendium of additional resources we hope will be helpful as the virus spreads and the disease unfolds. We continue to receive additional questions regarding clinical care and we are updating our FAQs on a regular basis.

We hope this information is helpful even when it merely confirms that there are no certain answers to many questions. Our answers are based on the best available information we identify in the literature, guidance from public health authorities, and input received from oncology and infectious disease experts.

For patients, we have posted a blog by Dr. Merry Jennifer Markham, chair of ASCO’s Cancer Communications Committee. This can be found on Cancer.Net, ASCO’s patient information website, and it provides practical guidance to help patients reduce their risk of exposure, better understand COVID-19 symptoms, and locate additional information.

This blog is available both in English and Spanish. Additional blog posts addressing patient questions will be posted as new questions are received and new information becomes available.

Find below a Tweet from Dr.Markham which includes links to her article on COVID-19 for cancer patients

https://twitter.com/DrMarkham/status/1237797251038220289?s=20

NCCN’s Response to COVID-19 and COVID-19 Resources

JNCCN: How to Manage Cancer Care during COVID-19 Pandemic

Experts from the Seattle Cancer Care Alliance (SCCA)—a Member Institution of the National Comprehensive Cancer Network® (NCCN®)—are sharing insights and advice on how to continue providing optimal cancer care during the novel coronavirus (COVID-19) pandemic. SCCA includes the Fred Hutchinson Cancer Research Center and the University of Washington, which are located in the epicenter of the COVID-19 outbreak in the United States. The peer-reviewed article sharing best practices is available for free online-ahead-of-print via open access at JNCCN.org.

Coronavirus disease 2019 (COVID-19) Resources for the Cancer Care Community

NCCN recognizes the rapidly changing medical information relating to COVID-19 in the oncology ecosystem, but understands that a forum for sharing best practices and specific institutional responses may be helpful to others.  Therefore, we are expeditiously providing documents and recommendations developed by NCCN Member Institutions or Guideline Panels as resources for oncology care providers. These resources have not been developed or reviewed by the standard NCCN processes, and are provided for information purposes only. We will post more resources as they become available so check back for additional updates.

Documents

Links

National Cancer Institute Response to COVID-19

More information at https://www.cancer.gov/contact/emergency-preparedness/coronavirus

What people with cancer should know: https://www.cancer.gov/coronavirus

Get the latest public health information from CDC: https://www.coronavirus.gov

Get the latest research information from NIH: https://www.nih.gov/coronavirus

 

Coronavirus: What People with Cancer Should Know

ON THIS PAGE

Both the resources at cancer.gov (NCI) as well as the resources from ASCO are updated as new information is evaluated and more guidelines are formulated by members of the oncologist and cancer care community and are excellent resources for those living with cancer, and also those who either care for cancer patients or their family and relatives.

Related Resources for Patients (please click on links)

 

 

 

Some resources and information for cancer patients from Twitter

Twitter feeds which may be useful sources of discussion and for cancer patients include:

 

@OncLive OncLive.com includes healthcare information for patients and includes videos and newsletters

 

 

@DrMarkham Dr. Markham is Chief of Heme-Onc & gyn med onc @UF | AD Med Affairs @UFHealthCancer and has collected very good information for patients concerning #Covid19 

 

 

@DrMaurieMarkman Dr. Maurie Markman is President of Medicine and Science (Cancer Centers of America, Philadelphia) @CancerCenter #TreatThePerson #Oncology #Genomics #PrecisionMedicine and hosts a great online live Tweet feed discussing current topics in cancer treatment and care for patients called #TreatThePerson Chat

UPDATED 3/20/2020 INFORMATION FROM NCI DESIGNATED CANCER CENTERS FOR PATIENTS/PROVIDERS

The following is a listing with links of NCI Designated Comprehensive Cancer Centers and some select designated Cancer Centers* which have information on infectious risk guidance for cancer patients as well as their physicians and caregivers.   There are 51 NCI Comprehensive Cancer Centers and as more cancer centers formulate guidance this list will be updated. 

 

Cancer Center State Link to COVID19 guidance
City of Hope CA Advice for cancer patients, survivors and caregivers
Jonsson Cancer Center at UCLA CA Cancer and COVID19
UCSF Hellen Diller Family Comprehensive Cancer CA COVID-19 Links for Patients and Providers
Lee Moffit FL Protecting against Coronavirus 19
University of Kansas Cancer Center* KS COVID19 Info for patients
Barbara & Karmanos Cancer Institute (Wayne State) MI COVID19 Resources
Rogel Cancer Center (Univ of Michigan) MI COVID19 Patient Specific Guidelines
Alvin J. Siteman Cancer Center (MO) Coronavirus
Fred & Pamela Buffet CC* NE Resources for Patients and Providers
Rutgers Cancer Institute of NJ NJ What patients should know about COVID19
Memorial Sloan Kettering NY What COVID19 means for cancer patients
Herbert Irving CC (Columbia University) NY Coronavirus Resource Center
MD Anderson Cancer  TX Planning for Patients, Providers
Hunstman Cancer Center UT COVID19 What you need to know
Fred Hutchinson WA COVID19 What patients need to know

 

 

Please also see related information on Coronavirus 2019 and Cancer and Immunotherapy at the following links on the Open Access Online Journal:

Volume Two: Cancer Therapies: Metabolic, Genomics, Interventional, Immunotherapy and Nanotechnology in Therapy Delivery 

at

https://pharmaceuticalintelligence.com/biomed-e-books/series-c-e-books-on-cancer-oncology/volume-two-immunotherapy-in-cancer-radiation-oncology/

AND

Coronavirus Portal

 

 

 

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

One of the most contagious diseases known to humankind, measles killed an average of 2.6 million people each year before a vaccine was developed, according to the World Health Organization. Widespread vaccination has slashed the death toll. However, lack of access to vaccination and refusal to get vaccinated means measles still infects more than 7 million people and kills more than 100,000 each year worldwide as reported by WHO. The cases are on the rise, tripling in early 2019 and some experience well-known long-term consequences, including brain damage and vision and hearing loss. Previous epidemiological research into immune amnesia suggests that death rates attributed to measles could be even higher, accounting for as much as 50 percent of all childhood mortality.

 

Over the last decade, evidence has mounted that the measles vaccine protects in two ways. It prevents the well-known acute illness with spots and fever and also appears to protect from other infections over the long term by giving general boost to the immune system. The measles virus can impair the body’s immune memory, causing so-called immune amnesia. By protecting against measles infection, the vaccine prevents the body from losing or “forgetting” its immune memory and preserves its resistance to other infections. Researchers showed that the measles virus wipes out 11% to 73% of the different antibodies that protect against viral and bacterial strains a person was previously immune to like from influenza to herpes virus to bacteria that cause pneumonia and skin infections.

 

This study at Harvard Medical School and their collaborators is the first to measure the immune damage caused by the virus and underscores the value of preventing measles infection through vaccination. The discovery that measles depletes people’s antibody repertoires, partially obliterating immune memory to most previously encountered pathogens, supports the immune amnesia hypothesis. It was found that those who survive measles gradually regain their previous immunity to other viruses and bacteria as they get re-exposed to them. But because this process may take months to years, people remain vulnerable in the meantime to serious complications of those infections and thus booster shots of routine vaccines may be required.

 

VirScan detects antiviral and antibacterial antibodies in the blood that result from current or past encounters with viruses and bacteria, giving an overall snapshot of the immune system. Researchers gathered blood samples from unvaccinated children during a 2013 measles outbreak in the Netherlands and used VirScan to measure antibodies before and two months after infection in 77 children who’d contracted the disease. The researchers also compared the measurements to those of 115 uninfected children and adults. Researchers found a striking drop in antibodies from other pathogens in the measles-infected children that clearly suggested a direct effect on the immune system resembling measles-induced immune amnesia.

 

Further tests revealed that severe measles infection reduced people’s overall immunity more than mild infection. This could be particularly problematic for certain categories of children and adults, the researchers said. The present study observed the effects in previously healthy children only. But, measles is known to hit malnourished children much harder, the degree of immune amnesia and its effects could be even more severe in less healthy populations. Inoculation with the MMR (measles, mumps, rubella) vaccine did not impair children’s overall immunity. The results align with decades of research. Ensuring widespread vaccination against measles would not only help prevent the expected 120,000 deaths that will be directly attributed to measles this year alone, but could also avert potentially hundreds of thousands of additional deaths attributable to the lasting damage to the immune system.

 

References:

 

https://hms.harvard.edu/news/inside-immune-amnesia?utm_source=Silverpop

 

https://science.sciencemag.org/content/366/6465/599

 

www.who.int/immunization/newsroom/measles-data-2019/en/

 

https://www.ncbi.nlm.nih.gov/pubmed/20636817

 

https://www.ncbi.nlm.nih.gov/pubmed/27157064

 

https://www.ncbi.nlm.nih.gov/pubmed/30797735

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Obesity is a global concern that is associated with many chronic complications such as type 2 diabetes, insulin resistance (IR), cardiovascular diseases, and cancer. Growing evidence has implicated the digestive system, including its microbiota, gut-derived incretin hormones, and gut-associated lymphoid tissue in obesity and IR. During high fat diet (HFD) feeding and obesity, a significant shift occurs in the microbial populations within the gut, known as dysbiosis, which interacts with the intestinal immune system. Similar to other metabolic organs, including visceral adipose tissue (VAT) and liver, altered immune homeostasis has also been observed in the small and large intestines during obesity.

 

A link between the gut microbiota and the intestinal immune system is the immune-derived molecule immunoglobulin A (IgA). IgA is a B cell antibody primarily produced in dimeric form by plasma cells residing in the gut lamina propria (LP). Given the importance of IgA on intestinal–gut microbe immunoregulation, which is directly influenced by dietary changes, scientists hypothesized that IgA may be a key player in the pathogenesis of obesity and IR. Here, in this study it was demonstrate that IgA levels are reduced during obesity and the loss of IgA in mice worsens IR and increases intestinal permeability, microbiota encroachment, and downstream inflammation in metabolic tissues, including inside the VAT.

 

IgA deficiency alters the obese gut microbiota and its metabolic phenotype can be recapitulated into microbiota-depleted mice upon fecal matter transplantation. In addition, the researchers also demonstrated that commonly used therapies for diabetes such as metformin and bariatric surgery can alter cellular and stool IgA levels, respectively. These findings suggested a critical function for IgA in regulating metabolic disease and support the emerging role for intestinal immunity as an important modulator of systemic glucose metabolism.

 

Overall, the researchers demonstrated a critical role for IgA in regulating intestinal homeostasis, metabolic inflammation, and obesity-related IR. These findings identify intestinal IgA+ immune cells as mucosal mediators of whole-body glucose regulation in diet-induced metabolic disease. This research further emphasized the importance of the intestinal adaptive immune system and its interactions with the gut microbiota and innate immune system within the larger network of organs involved in the manifestation of metabolic disease.

 

Future investigation is required to determine the impact of IgA deficiency during obesity in humans and the role of metabolic disease in human populations with selective IgA deficiency, especially since human IgA deficiency is associated with an altered gut microbiota that cannot be fully compensated with IgM. However, the research identified IgA as a critical immunological molecule in the intestine that impacts systemic glucose homeostasis, and treatments targeting IgA-producing immune populations and SIgA may have therapeutic potential for metabolic disease.

 

References:

 

https://www.nature.com/articles/s41467-019-11370-y?elqTrackId=dc86e0c60f574542b033227afd0fdc8e

 

https://www.jci.org/articles/view/88879

 

https://www.nature.com/articles/nm.2353

 

https://diabetes.diabetesjournals.org/content/57/6/1470

 

https://www.sciencedirect.com/science/article/pii/S1550413115001047?via%3Dihub

 

https://www.sciencedirect.com/science/article/pii/S1550413115002326?via%3Dihub

 

https://www.sciencedirect.com/science/article/pii/S1931312814004636?via%3Dihub

 

https://www.nature.com/articles/nature15766

 

https://www.sciencedirect.com/science/article/pii/S1550413116000371?via%3Dihub

 

https://www.nature.com/articles/nm.2001

 

https://www.sciencedirect.com/science/article/abs/pii/S1550413118305047?via%3Dihub

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

When a baby is born through its mother’s birth canal, it is bathed in a soup of microbes. Those born by caesarean section (C-section) miss out on this bacterial baptism. The differences in microbe exposure at birth and later health could be caused by other factors, such as whether a mother takes antibiotics during her surgery, and whether a baby is breastfed or has a genetic predisposition to obesity. So, the researchers are sharply split on whether or not this missing of bacterial exposure increases the risk of chronic health problems such as obesity and asthma.

 

Researchers found that babies delivered surgically harboured different collections of bacteria than did those born vaginally. C-section babies, which comprise more than 30% of births in the United States, are also more prone to obesity and immune diseases such as diabetes. Experiments show that mice born by C-section are more prone to obesity and have impaired immune systems. There are fewer factors that could account for these differences in the rodents, which can be studied in controlled conditions, than in people.

 

A wave of clinical trials now under way could help to settle the question — and feed into the debate over whether seeding babies born by C-section with their mother’s vaginal bacteria is beneficial or potentially harmful. Several groups of researchers will be swabbing hundreds of C-section babies with their mother’s microbes, while comparing them to a control group. Each team plans to monitor its study participants over several years in the hope of learning more about how the collection of microbes in their bodies might influence weight, allergy risk and other factors.

 

But some scientists say that the trials could expose C-section babies to infection, or encourage mothers to try do-it-yourself swabbing, without much evidence that there is a benefit or risk. Moreover, there is no evidence that differing exposure to vaginal microbes at birth can help explain variation in people’s health over time. Presently the whole concept is in very much a state of uncertainty.

 

Researchers in near future will compare swabbed C-section babies with a placebo group and with infants delivered vaginally. They confirmed that their protocols will not increase the risk of infection for C-section babies. Scientists will also rigorously screen mothers participating in these trials for microbes such as HIV and group B streptococcus — a common vaginal bacterium that causes respiratory problems in newborns.

 

References:

 

https://www.nature.com/articles/d41586-019-02348-3?utm_source=Nature+Briefing

 

https://www.ncbi.nlm.nih.gov/pubmed/31431742

 

https://www.ncbi.nlm.nih.gov/pubmed/20566857

 

https://www.ncbi.nlm.nih.gov/pubmed/25452656

 

https://www.ncbi.nlm.nih.gov/pubmed/22939691

 

https://www.ncbi.nlm.nih.gov/pubmed/24030708

 

https://pharmaceuticalintelligence.com/2017/02/22/babys-microbiome-changing-due-to-caesarean-birth-and-formula-feeding/

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The Journey of Antibiotic Discovery

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

The term ‘antibiotic’ was introduced by Selman Waksman as any small molecule, produced by a microbe, with antagonistic properties on the growth of other microbes. An antibiotic interferes with bacterial survival via a specific mode of action but more importantly, at therapeutic concentrations, it is sufficiently potent to be effective against infection and simultaneously presents minimal toxicity. Infectious diseases have been a challenge throughout the ages. From 1347 to 1350, approximately one-third of Europe’s population perished to Bubonic plague. Advances in sanitary and hygienic conditions sufficed to control further plague outbreaks. However, these persisted as a recurrent public health issue. Likewise, infectious diseases in general remained the leading cause of death up to the early 1900s. The mortality rate shrunk after the commercialization of antibiotics, which given their impact on the fate of mankind, were regarded as a ‘medical miracle’. Moreover, the non-therapeutic application of antibiotics has also greatly affected humanity, for instance those used as livestock growth promoters to increase food production after World War II.

 

Currently, more than 2 million North Americans acquire infections associated with antibiotic resistance every year, resulting in 23,000 deaths. In Europe, nearly 700 thousand cases of antibiotic-resistant infections directly develop into over 33,000 deaths yearly, with an estimated cost over €1.5 billion. Despite a 36% increase in human use of antibiotics from 2000 to 2010, approximately 20% of deaths worldwide are related to infectious diseases today. Future perspectives are no brighter, for instance, a government commissioned study in the United Kingdom estimated 10 million deaths per year from antibiotic resistant infections by 2050.

 

The increase in antibiotic-resistant bacteria, alongside the alarmingly low rate of newly approved antibiotics for clinical usage, we are on the verge of not having effective treatments for many common infectious diseases. Historically, antibiotic discovery has been crucial in outpacing resistance and success is closely related to systematic procedures – platforms – that have catalyzed the antibiotic golden age, namely the Waksman platform, followed by the platforms of semi-synthesis and fully synthetic antibiotics. Said platforms resulted in the major antibiotic classes: aminoglycosides, amphenicols, ansamycins, beta-lactams, lipopeptides, diaminopyrimidines, fosfomycins, imidazoles, macrolides, oxazolidinones, streptogramins, polymyxins, sulphonamides, glycopeptides, quinolones and tetracyclines.

 

The increase in drug-resistant pathogens is a consequence of multiple factors, including but not limited to high rates of antimicrobial prescriptions, antibiotic mismanagement in the form of self-medication or interruption of therapy, and large-scale antibiotic use as growth promotors in livestock farming. For example, 60% of the antibiotics sold to the USA food industry are also used as therapeutics in humans. To further complicate matters, it is estimated that $200 million is required for a molecule to reach commercialization, with the risk of antimicrobial resistance rapidly developing, crippling its clinical application, or on the opposing end, a new antibiotic might be so effective it is only used as a last resort therapeutic, thus not widely commercialized.

 

Besides a more efficient management of antibiotic use, there is a pressing need for new platforms capable of consistently and efficiently delivering new lead substances, which should attend their precursors impressively low rates of success, in today’s increasing drug resistance scenario. Antibiotic Discovery Platforms are aiming to screen large libraries, for instance the reservoir of untapped natural products, which is likely the next antibiotic ‘gold mine’. There is a void between phenotanypic screening (high-throughput) and omics-centered assays (high-information), where some mechanistic and molecular information complements antimicrobial activity, without the laborious and extensive application of various omics assays. The increasing need for antibiotics drives the relentless and continuous research on the foreground of antibiotic discovery. This is likely to expand our knowledge on the biological events underlying infectious diseases and, hopefully, result in better therapeutics that can swing the war on infectious diseases back in our favor.

 

During the genomics era came the target-based platform, mostly considered a failure due to limitations in translating drugs to the clinic. Therefore, cell-based platforms were re-instituted, and are still of the utmost importance in the fight against infectious diseases. Although the antibiotic pipeline is still lackluster, especially of new classes and novel mechanisms of action, in the post-genomic era, there is an increasingly large set of information available on microbial metabolism. The translation of such knowledge into novel platforms will hopefully result in the discovery of new and better therapeutics, which can sway the war on infectious diseases back in our favor.

 

References:

 

https://www.mdpi.com/2079-6382/8/2/45/htm

 

https://www.ncbi.nlm.nih.gov/pubmed/19515346

 

https://www.ajicjournal.org/article/S0196-6553(11)00184-2/fulltext

 

https://www.ncbi.nlm.nih.gov/pubmed/21700626

 

http://www.med.or.jp/english/journal/pdf/2009_02/103_108.pdf

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Gender of a person can affect the kinds of cancer-causing mutations they develop, according to a genomic analysis spanning nearly 2,000 tumours and 28 types of cancer. The results show striking differences in the cancer-causing mutations found in people who are biologically male versus those who are biologically female — not only in the number of mutations lurking in their tumours, but also in the kinds of mutations found there.

 

Liver tumours from women were more likely to carry mutations caused by a faulty system of DNA mending called mismatch repair, for instance. And men with any type of cancer were more likely to exhibit DNA changes thought to be linked to a process that the body uses to repair DNA with two broken strands. These biases could point researchers to key biological differences in how tumours develop and evolve across sexes.

 

The data add to a growing realization that sex is important in cancer, and not only because of lifestyle differences. Lung and liver cancer, for example, are more common in men than in women — even after researchers control for disparities in smoking or alcohol consumption. The source of that bias, however, has remained unclear.

In 2014, the US National Institutes of Health began encouraging researchers to consider sex differences in preclinical research by, for example, including female animals and cell lines from women in their studies. And some studies have since found sex-linked biases in the frequency of mutations in protein-coding genes in certain cancer types, including some brain cancers and advanced melanoma.

 

But the present study is the most comprehensive study of sex differences in tumour genomes so far. It looks at mutations not only in genes that code for proteins, but also in the vast expanses of DNA that have other functions, such as controlling when genes are turned on or off. The study also compares male and female genomes across many different cancers, which can allow researchers to pick up on additional patterns of DNA mutations, in part by increasing the sample sizes.

 

Researchers analysed full genome sequences gathered by the International Cancer Genome Consortium. They looked at differences in the frequency of 174 mutations known to drive cancer, and found that some of these mutations occurred more frequently in men than in women, and vice versa. When they looked more broadly at the loss or duplication of DNA segments in the genome, they found 4,285 sex-biased genes spread across 15 chromosomes.

 

There were also differences found when some mutations seemed to arise during tumour development, suggesting that some cancers follow different evolutionary paths in men and women. Researchers also looked at particular patterns of DNA changes. Such patterns can, in some cases, reflect the source of the mutation. Tobacco smoke, for example, leaves behind a particular signature in the DNA.

 

Taken together, the results highlight the importance of accounting for sex, not only in clinical trials but also in preclinical studies. This could eventually allow researchers to pin down the sources of many of the differences found in this study. Liver cancer is roughly three times as common in men as in women in some populations, and its incidence is increasing in some countries. A better understanding of its aetiology may turn out to be really important for prevention strategies and treatments.

 

References:

 

https://www.nature.com/articles/d41586-019-00562-7?utm_source=Nature+Briefing

 

https://www.nature.com/news/policy-nih-to-balance-sex-in-cell-and-animal-studies-1.15195

 

https://www.ncbi.nlm.nih.gov/pubmed/26296643

 

https://www.biorxiv.org/content/10.1101/507939v1

 

https://www.ncbi.nlm.nih.gov/pubmed/25985759

 

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