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Archive for the ‘Stem Cells for Regenerative Medicine’ Category


  1. Lungs can supply blood stem cells and also produce platelets: Lungs, known primarily for breathing, play a previously unrecognized role in blood production, with more than half of the platelets in a mouse’s circulation produced there. Furthermore, a previously unknown pool of blood stem cells has been identified that is capable of restoring blood production when bone marrow stem cells are depleted.

 

  1. A new drug for multiple sclerosis: A new multiple sclerosis (MS) drug, which grew out of the work of UCSF (University of California, San Francisco) neurologist was approved by the FDA. Ocrelizumab, the first drug to reflect current scientific understanding of MS, was approved to treat both relapsing-remitting MS and primary progressive MS.

 

  1. Marijuana legalized – research needed on therapeutic possibilities and negative effects: Recreational marijuana will be legal in California starting in January, and that has brought a renewed urgency to seek out more information on the drug’s health effects, both positive and negative. UCSF scientists recognize marijuana’s contradictory status: the drug has proven therapeutic uses, but it can also lead to tremendous public health problems.

 

  1. Source of autism discovered: In a finding that could help unlock the fundamental mysteries about how events early in brain development lead to autism, researchers traced how distinct sets of genetic defects in a single neuronal protein can lead to either epilepsy in infancy or to autism spectrum disorders in predictable ways.

 

  1. Protein found in diet responsible for inflammation in brain: Ketogenic diets, characterized by extreme low-carbohydrate, high-fat regimens are known to benefit people with epilepsy and other neurological illnesses by lowering inflammation in the brain. UCSF researchers discovered the previously undiscovered mechanism by which a low-carbohydrate diet reduces inflammation in the brain. Importantly, the team identified a pivotal protein that links the diet to inflammatory genes, which, if blocked, could mirror the anti-inflammatory effects of ketogenic diets.

 

  1. Learning and memory failure due to brain injury is now restorable by drug: In a finding that holds promise for treating people with traumatic brain injury, an experimental drug, ISRIB (integrated stress response inhibitor), completely reversed severe learning and memory impairments caused by traumatic brain injury in mice. The groundbreaking finding revealed that the drug fully restored the ability to learn and remember in the brain-injured mice even when the animals were initially treated as long as a month after injury.

 

  1. Regulatory T cells induce stem cells for promoting hair growth: In a finding that could impact baldness, researchers found that regulatory T cells, a type of immune cell generally associated with controlling inflammation, directly trigger stem cells in the skin to promote healthy hair growth. An experiment with mice revealed that without these immune cells as partners, stem cells cannot regenerate hair follicles, leading to baldness.

 

  1. More intake of good fat is also bad: Liberal consumption of good fat (monounsaturated fat) – found in olive oil and avocados – may lead to fatty liver disease, a risk factor for metabolic disorders like type 2 diabetes and hypertension. Eating the fat in combination with high starch content was found to cause the most severe fatty liver disease in mice.

 

  1. Chemical toxicity in almost every daily use products: Unregulated chemicals are increasingly prevalent in products people use every day, and that rise matches a concurrent rise in health conditions like cancers and childhood diseases, Thus, researcher in UCSF is working to understand the environment’s role – including exposure to chemicals – in health conditions.

 

  1. Cytomegalovirus found as common factor for diabetes and heart disease in young women: Cytomegalovirus is associated with risk factors for type 2 diabetes and heart disease in women younger than 50. Women of normal weight who were infected with the typically asymptomatic cytomegalovirus, or CMV, were more likely to have metabolic syndrome. Surprisingly, the reverse was found in those with extreme obesity.

 

References:

 

https://www.ucsf.edu/news/2017/12/409241/most-popular-science-stories-2017

 

https://www.ucsf.edu/news/2017/03/406111/surprising-new-role-lungs-making-blood

 

https://www.ucsf.edu/news/2017/03/406296/new-multiple-sclerosis-drug-ocrelizumab-could-halt-disease

 

https://www.ucsf.edu/news/2017/06/407351/dazed-and-confused-marijuana-legalization-raises-need-more-research

 

https://www.ucsf.edu/news/2017/01/405631/autism-researchers-discover-genetic-rosetta-stone

 

https://www.ucsf.edu/news/2017/09/408366/how-ketogenic-diets-curb-inflammation-brain

 

https://www.ucsf.edu/news/2017/07/407656/drug-reverses-memory-failure-caused-traumatic-brain-injury

 

https://www.ucsf.edu/news/2017/05/407121/new-hair-growth-mechanism-discovered

 

https://www.ucsf.edu/news/2017/06/407536/go-easy-avocado-toast-good-fat-can-still-be-bad-you-research-shows

 

https://www.ucsf.edu/news/2017/06/407416/toxic-exposure-chemicals-are-our-water-food-air-and-furniture

 

https://www.ucsf.edu/news/2017/02/405871/common-virus-tied-diabetes-heart-disease-women-under-50

 

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First Haploid Human Stem Cells

Reported: Irina Robu, PhD

Most of the cells in our body are diploid, which indicate they carry two sets of chromosomes—one from each parent. So far, scientists have only succeeded in generating haploid embryonic stem cells—which comprise a single set of chromosomes in non-human mammals such as mice, rats and monkeys. Nevertheless, scientists have tried to isolate and duplicate these haploid ESCs in humans, which would allow them to work with one set of human chromosomes as opposed to a mixture from both parents.

Scientists from Hebrew from The Hebrew University of Jerusalem, Columbia University Medical Center (CUMC) and The New York Stem Cell Foundation Research Institute (NYSCF) were successful in generating a new type of embryonic stem cells that has a single copy of the human genome, instead of two copies which is typically found in normal stem cells.

This landmark was finally obtained by Ido Sagi, working as a PhD student at the Hebrew University of Jerusalem which was successful in isolating and maintaining haploid embryonic stem cells in humans. Unlike in mice, these haploid stem cells were capable to differentiate into various cell types such as brain, heart and pancreas, although holding a single set of chromosomes. Sagi and his advisor, Prof. Nissim Benvenisty showed that this new human stem cell type will play an important role in human genetic and medical research.  This new human cell type cell type will aid in understanding human development and it will make genetic screening simpler and more precise, by examining a single set of chromosomes.

Based on this research, the Technology Transfer arm of the Hebrew University, started a new company New Stem, which is developing a diagnostic kit for predicting resistance to chemotherapy treatments. By gathering a broad library of human pluripotent stem cells with various genetic makeups and mutations. The company is planning to use this kit for personalized medication and future therapeutic and reproductive products.

SOURCE

https://medicalxpress.com/news/2017-06-haploid-human-stem-cells-medical.html#jCp

Other related articles published in this Open Access Online Scientific Journal include the following:

Ido Sagi – PhD Student @HUJI, 2017 Kaye Innovation Award winner for leading research that yielded the first successful isolation and maintenance of haploid embryonic stem cells in humans.

Reporter: Aviva Lev-Ari, PhD, RN

Ido Sagi – PhD Student @HUJI, 2017 Kaye Innovation Award winner for leading research that yielded the first successful isolation and maintenance of haploid embryonic stem cells in humans.

 

 

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Ido Sagi – PhD Student @HUJI, 2017 Kaye Innovation Award winner for leading research that yielded the first successful isolation and maintenance of haploid embryonic stem cells in humans.

Reporter: Aviva Lev-Ari, PhD, RN

 

Ido Sagi – PhD Student, Silberman Institute of Life Sciences, HUJI, Israel

  • Ido Sagi’s research focuses on studying genetic and epigenetic phenomena in human pluripotent stem cells, and his work has been published in leading scientific journals, including NatureNature Genetics and Cell Stem Cell.
  • Ido Sagi received BSc summa cum laude in Life Sciences from the Hebrew University, and currently pursues a PhD at the laboratory of Prof. Nissim Benvenisty at the university’s Department of Genetics in the Alexander Silberman Institute of Life Sciences.

The Kaye Innovation Awards at the Hebrew University of Jerusalem have been awarded annually since 1994. Isaac Kaye of England, a prominent industrialist in the pharmaceutical industry, established the awards to encourage faculty, staff and students of the Hebrew University to develop innovative methods and inventions with good commercial potential, which will benefit the university and society.

Publications – Ido Sagi

Comparable frequencies of coding mutations and loss of imprinting in human pluripotent cells derived by nuclear transfer and defined factors.
Cell Stem Cell 2014 Nov 6;15(5):634-42. Epub 2014 Nov 6.
The New York Stem Cell Foundation Research Institute, New York, NY 10032, USA; Naomi Berrie Diabetes Center & Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA. Electronic address:

November 2014

 



Stem cells: Aspiring to naivety.
Nature 2016 12 30;540(7632):211-212. Epub 2016 Nov 30.
The Azrieli Center for Stem Cells and Genetic Research, Department of Genetics, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
November 2016

Download Full Paper

SOURCE

Other related articles on Genetic and Epigenetic phenomena in human pluripotent stem cells published by LPBI Group can be found in the following e-Books on Amazon.com

e-Books in Medicine

https://www.amazon.com/s/ref=dp_byline_sr_ebooks_9?ie=UTF8&text=Aviva+Lev-Ari&search-alias=digital-text&field-author=Aviva+Lev-Ari&sort=relevancerank

9 results for Kindle Store : “Aviva Lev-Ari”

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    Etiologies of Cardiovascular Diseases: Epigenetics, Genetics and Genomics

    Nov 28, 2015 | Kindle eBook

    by Justin D. Pearlman MD ME PhD MA FACC and Stephen J. Williams PhD
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    Cancer Therapies: Metabolic, Genomics, Interventional, Immunotherapy and Nanotechnology in Therapy Delivery (Series C Book 2)

    May 13, 2017 | Kindle eBook

    by Larry H. Bernstein and Demet Sag
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    Perspectives on Nitric Oxide in Disease Mechanisms (Biomed e-Books Book 1)

    Jun 20, 2013 | Kindle eBook

    by Margaret Baker PhD and Aviva Lev-Ari PhD RN
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    Cancer Biology and Genomics for Disease Diagnosis (Series C: e-Books on Cancer & Oncology Book 1)

    Aug 10, 2015 | Kindle eBook

    by Larry H Bernstein MD FCAP and Prabodh Kumar Kandala PhD
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    Genomics Orientations for Personalized Medicine (Frontiers in Genomics Research Book 1)

    Nov 22, 2015 | Kindle eBook

    by Sudipta Saha PhD and Ritu Saxena PhD
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    Metabolic Genomics & Pharmaceutics (BioMedicine – Metabolomics, Immunology, Infectious Diseases Book 1)

    Jul 21, 2015 | Kindle eBook

    by Larry H. Bernstein MD FCAP and Prabodah Kandala PhD
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    Milestones in Physiology: Discoveries in Medicine, Genomics and Therapeutics (Series E: Patient-Centered Medicine Book 3)

    Dec 26, 2015 | Kindle eBook

    by Larry H. Bernstein MD FACP and Aviva Lev-Ari PhD RN
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    Regenerative and Translational Medicine: The Therapeutic Promise for Cardiovascular Diseases

    Dec 26, 2015 | Kindle eBook

    by Justin D. Pearlman MD ME PhD MA FACC and Ritu Saxena PhD
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    Cardiovascular Original Research: Cases in Methodology Design for Content Co-Curation: The Art of Scientific & Medical Curation

    Nov 29, 2015 | Kindle eBook

    by Larry H. Bernstein MD FCAP and Aviva Lev-Ari PhD RN
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cvd-series-a-volume-iv-cover

Series A: e-Books on Cardiovascular Diseases

Series A Content Consultant: Justin D Pearlman, MD, PhD, FACC

VOLUME FOUR

Regenerative and Translational Medicine

The Therapeutic Promise for

Cardiovascular Diseases

  • on Amazon since 12/26/2015

http://www.amazon.com/dp/B019UM909A

 

by  

Larry H Bernstein, MD, FCAP, Senior Editor, Author and Curator

and

Aviva Lev-Ari, PhD, RN, Editor and Curator

 

Part One:

Cardiovascular Diseases,Translational Medicine (TM) and Post TM

Introduction to Part 1: Cardiovascular Diseases,Translational Medicine (TM) and Post TM

Chapter 1: Translational Medicine Concepts

1.0 Post-Translational Modification of Proteins

1.1 Identifying Translational Science within the Triangle of Biomedicine

1.2 State of Cardiology on Wall Stress, Ventricular Workload and Myocardial Contractile Reserve: Aspects of Translational Medicine (TM)

1.3 Risk of Bias in Translational Science

1.4 Biosimilars: Intellectual Property Creation and Protection by Pioneer and by Biosimilar Manufacturers

Chapter 2: Causes and the Etiology of Cardiovascular Diseases: Translational Approaches for Cardiothoracic Medicine

2.1 Genomics

2.1.1 Genomics-Based Classification

2.1.2  Targeting Untargetable Proto-Oncogenes

2.1.3  Searchable Genome for Drug Development

2.1.4 Zebrafish Study Tool

2.1.5  International Human Genome Sequencing Consortium (2004) Finishing the euchromatic sequence of the human genome.

2.2  Proteomics

2.2.1 The Role of Tight Junction Proteins in Water and Electrolyte Transport

2.2.2 Selective Ion Conduction

2.2.3 Translational Research on the Mechanism of Water and Electrolyte Movements into the Cell

2.2.4 Inhibition of the Cardiomyocyte-Specific Kinase TNNI3K ­ Oxidative Stress

2.2.5 Oxidized Calcium Calmodulin Kinase and Atrial Fibrillation

2.2.6 S-Nitrosylation in Cardiac Ischemia and Acute Coronary Syndrome

2.2.7 Acetylation and Deacetylation

2.2.8 Nitric Oxide Synthase Inhibitors (NOS-I) 

2.3 Cardiac and Vascular Signaling

2.3.1 The Centrality of Ca(2+) Signaling and Cytoskeleton Involving Calmodulin Kinases and Ryanodine Receptors in Cardiac Failure, Arterial Smooth Muscle, Post-ischemic Arrhythmia, Similarities and Differences, and Pharmaceutical Targets

2.3.2 Leptin Signaling in Mediating the Cardiac Hypertrophy associated with Obesity

2.3.3 Triggering of Plaque Disruption and Arterial Thrombosis

2.3.4 Sensors and Signaling in Oxidative Stress

2.3.5 Resistance to Receptor of Tyrosine Kinase

2.3.6  S-nitrosylation signaling in cell biology.

2.4  Platelet Endothelial Interaction

2.4.1 Platelets in Translational Research ­ 1

2.4.2 Platelets in Translational Research ­ 2: Discovery of Potential Anti-platelet Targets

2.4.3 The Final Considerations of the Role of Platelets and Platelet Endothelial Reactions in Atherosclerosis and Novel Treatments

2.4.4 Endothelial Function and Cardiovascular Disease
Larry H Bernstein, MD, FCAP

2.5 Post-translational modifications (PTMs)

2.5.1 Post-Translational Modifications

2.5.2.  Analysis of S-nitrosylated Proteins

2.5.3  Mechanisms of Disease: Signal Transduction: Akt Phosphorylates HK-II at Thr-473 and Increases Mitochondrial HK-II Association to Protect Cardiomyocytes

2.5.4  Acetylation and Deacetylation of non-Histone Proteins

2.5.5  Study Finds Low Methylation Regions Prone to Structural Mutation

2.6 Epigenetics and lncRNAs

2.6.1 The Magic of the Pandora’s Box : Epigenetics and Stemness with Long non-coding RNAs (lincRNA)

2.6.2 The SILENCE of the Lambs” Introducing The Power of Uncoded RNA

2.6.3 Long Noncoding RNA Network regulates PTEN Transcription

2.6.4 How mobile elements in “Junk” DNA promote cancer. Part 1: Transposon-mediated tumorigenesis.

2.6.5 Transposon-mediated Gene Therapy improves Pulmonary Hemodynamics and attenuates Right Ventricular Hypertrophy: eNOS gene therapy reduces Pulmonary vascular remodeling and Arterial wall hyperplasia

2.6.6 Junk DNA codes for valuable miRNAs: non-coding DNA controls Diabetes

2.6.7 Targeted Nucleases

2.6.8 Late Onset of Alzheimer’s Disease and One-carbon Metabolism
Dr. Sudipta Saha

2.6.9 Amyloidosis with Cardiomyopathy

2.6.10 Long non-coding RNAs: Molecular Regulators of Cell Fate

2.7 Metabolomics

2.7.1 Expanding the Genetic Alphabet and Linking the Genome to the Metabolome

2.7.2 How Methionine Imbalance with Sulfur-Insufficiency Leads to Hyperhomocysteinemia

2.7.3 A Second Look at the Transthyretin Nutrition Inflammatory Conundrum

2.7.4 Transthyretin and Lean Body Mass in Stable and Stressed State

2.7.5 Hyperhomocysteinemia interaction with Protein C and Increased Thrombotic Risk

2.7.6 Telling NO to Cardiac Risk

2.8 Mitochondria and Oxidative Stress

2.8.1 Reversal of Cardiac Mitochondrial Dysfunction

2.8.2 Calcium Signaling, Cardiac Mitochondria and Metabolic Syndrome

2.8.3. Mitochondrial Dysfunction and Cardiac Disorders

2.8.4 Mitochondrial Metabolism and Cardiac Function

2.8.5 Mitochondria and Cardiovascular Disease: A Tribute to Richard Bing

2.8.6 MIT Scientists on Proteomics: All the Proteins in the Mitochondrial Matrix Identified

2.8.7 Mitochondrial Dynamics and Cardiovascular Diseases

2.8.8 Mitochondrial Damage and Repair under Oxidative Stress

2.8.9 Nitric Oxide has a Ubiquitous Role in the Regulation of Glycolysis -with a Concomitant Influence on Mitochondrial Function

2.8.10 Mitochondrial Mechanisms of Disease in Diabetes Mellitus

2.8.11 Mitochondria Dysfunction and Cardiovascular Disease – Mitochondria: More than just the “Powerhouse of the Cell”

Chapter 3: Risks and Biomarkers for Diagnosis and Prognosis in Translational Cardiothoracic Medicine

3.1 Biomarkers. Diagnosis and Management: Biomarkers. Present and Future.

3.2 Landscape of Cardiac Biomarkers for Improved Clinical Utilization

3.3 Achieving Automation in Serology: A New Frontier in Best

3.4 Accurate Identification and Treatment of Emergent Cardiac Events

3.5 Prognostic Marker Importance of Troponin I in Acute Decompensated Heart Failure (ADHF)

3.6 High-Sensitivity Cardiac Troponin Assays Preparing the United States for High-Sensitivity Cardiac Troponin Assays

3.7 Voices from the Cleveland Clinic On Circulating apoA1: A Biomarker for a Proatherogenic Process in the Artery Wall

3.8 Triggering of Plaque Disruption and Arterial Thrombosis

3.9 Relationship between Adiposity and High Fructose Intake Revealed

3.10 The Cardio-Renal Syndrome (CRS) in Heart Failure (HF)

3.11 Aneuploidy and Carcinogenesis

3.12 “Sudden Cardiac Death,” SudD is in Ferrer inCode’s Suite of Cardiovascular Genetic Tests to be Commercialized in the US

Chapter 4: Therapeutic Aspects in Translational Cardiothoracic Medicine

4.1 Molecular and Cellular Cardiology

4.1.1 αllbβ3 Antagonists As An Example of Translational Medicine Therapeutics

4.1.2 Three-Dimensional Fibroblast Matrix Improves Left Ventricular Function post MI

4.1.3 Biomaterials Technology: Models of Tissue Engineering for Reperfusion and Implantable Devices for Revascularization

4.1.4 CELLWAVE Randomized Clinical Trial: Modest improvement in LVEF at 4 months ­ “Shock wave­facilitated intracoronary administration of BMCs” vs “Shock wave treatment alone”

4.1.5 Prostacyclin and Nitric Oxide: Adventures in vascular biology –  a tale of two mediators

4.1.6 Cardiac Contractility & Myocardium Performance: Ventricular Arrhythmiasand Non-ischemic Heart Failure – Therapeutic Implications for Cardiomyocyte Ryanopathy

4.1.7 Publications on Heart Failure by Prof. William Gregory Stevenson, M.D., BWH

4.2 Interventional Cardiology and Cardiac Surgery – Mechanical Circulatory Support and Vascular Repair

4.2.1 Mechanical Circulatory Support System, LVAD, RVAD, Biventricular as a Bridge to Heart Transplantation or as “Destination Therapy”: Options for Patients in Advanced Heart Failure

4.2.2 Heart Transplantation: NHLBI’s Ten Year Strategic Research Plan to Achieving Evidence-based Outcomes

4.2.3 Improved Results for Treatment of Persistent type 2 Endoleak after Endovascular Aneurysm Repair: Onyx Glue Embolization

4.2.4 Carotid Endarterectomy (CEA) vs. Carotid Artery Stenting (CAS): Comparison of CMMS high-risk criteria on the Outcomes after Surgery: Analysis of the Society for Vascular Surgery (SVS) Vascular Registry Data

4.2.5 Effect of Hospital Characteristics on Outcomes of Endovascular Repair of Descending Aortic Aneurysms in US Medicare Population

4.2.6 Hypertension and Vascular Compliance: 2013 Thought Frontier – An Arterial Elasticity Focus

4.2.7 Preventive Medicine Philosophy: Excercise vs. Drug, IF More of the First THEN Less of the Second

4.2.8 Cardio-oncology and Onco-Cardiology Programs: Treatments for Cancer Patients with a History of Cardiovascular Disease

Summary to Part One

 

Part Two:

Cardiovascular Diseases and Regenerative Medicine

Introduction to Part Two

Chapter 1: Stem Cells in Cardiovascular Diseases

1.1 Regeneration: Cardiac System (cardiomyogenesis) and Vasculature (angiogenesis)

1.2 Notable Contributions to Regenerative Cardiology by Richard T. Lee (Lee’s Lab, Part I)

1.3 Contributions to Cardiomyocyte Interactions and Signaling (Lee’s Lab, Part II)

1.4 Jmjd3 and Cardiovascular Differentiation of Embryonic Stem Cells

1.5 Stem Cell Therapy for Coronary Artery Disease (CAD)

1.6 Intracoronary Transplantation of Progenitor Cells after Acute MI

1.7 Progenitor Cell Transplant for MI and Cardiogenesis (Part 1)

1.8 Source of Stem Cells to Ameliorate Damage Myocardium (Part 2)

1.9 Neoangiogenic Effect of Grafting an Acellular 3-Dimensional Collagen Scaffold Onto Myocardium (Part 3)

1.10 Transplantation of Modified Human Adipose Derived Stromal Cells Expressing VEGF165

1.11 Three-Dimensional Fibroblast Matrix Improves Left Ventricular Function Post MI

Chapter 2: Regenerative Cell and Molecular Biology

2.1 Circulating Endothelial Progenitors Cells (cEPCs) as Biomarkers

2.2 Stem Cell Research — The Frontier at the Technion in Israel

2.3 Blood vessel-generating stem cells discovered

2.4 Heart Renewal by pre-existing Cardiomyocytes: Source of New Heart Cell Growth Discovered

2.5 The Heart: Vasculature Protection – A Concept-based Pharmacological Therapy including THYMOSIN

2.6 Innovations in Bio instrumentation for Measurement of Circulating Progenetor Endothelial Cells in Human Blood.

2.7 Endothelial Differentiation and Morphogenesis of Cardiac Precursor

Chapter 3: Therapeutics Levels In Molecular Cardiology

3.1 Secrets of Your Cells: Discovering Your Body’s Inner Intelligence (Sounds True, on sale May 1, 2013) by Sondra Barrett

3.2 Human Embryonic-Derived Cardiac Progenitor Cells for Myocardial Repair

3.3 Repair using iPPCs or Stem Cells

3.3.1 Reprogramming cell in Tissue Repair

3.3.2 Heart patients’ skin cells turned into healthy heart muscle cells

3.4 Arteriogenesis and Cardiac Repair: Two Biomaterials – Injectable Thymosin beta4 and Myocardial Matrix Hydrogel 

3.5 Cardiovascular Outcomes: Function of circulating Endothelial Progenitor Cells (cEPCs): Exploring Pharmaco-therapy targeted at Endogenous Augmentation of cEPCs

3.6 Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD

Chapter 4: Research Proposals for Endogenous Augmentation of circulating Endothelial Progenitor Cells (cEPCs)

4.1 Peroxisome proliferator-activated receptor (PPAR-gamma) Receptors Activation: PPARγ transrepression for Angiogenesis in Cardiovascular Disease and PPARγ transactivation for Treatment of Diabetes

4.2 Clinical Trials Results for Endothelin System: Pathophysiological role in Chronic Heart Failure, Acute Coronary Syndromes and MI – Marker of Disease Severity or Genetic Determination?

4.3 Endothelin Receptors in Cardiovascular Diseases: The Role of eNOS Stimulation

4.4 Inhibition of ET-1, ETA and ETA-ETB, Induction of NO production, stimulation of eNOS and Treatment Regime with PPAR-gamma agonists (TZD): cEPCs Endogenous Augmentation for Cardiovascular Risk Reduction – A Bibliography

4.5 Positioning a Therapeutic Concept for Endogenous Augmentation of cEPCs — Therapeutic Indications for Macrovascular Disease: Coronary, Cerebrovascular and Peripheral

4.6 Endothelial Dysfunction, Diminished Availability of cEPCs, Increasing CVD Risk for Macrovascular Disease – Therapeutic Potential of cEPCs

4.7 Vascular Medicine and Biology: CLASSIFICATION OF FAST ACTING THERAPY FOR PATIENTS AT HIGH RISK FOR MACROVASCULAR EVENTS Macrovascular Disease – Therapeutic Potential of cEPCs

4.8 Cardiovascular Disease (CVD) and the Role of agent alternatives in endothelial Nitric Oxide Synthase (eNOS) Activation and Nitric Oxide Production

4.9 Resident-cell-based Therapy in Human Ischaemic Heart Disease: Evolution in the PROMISE of Thymosin beta4 for Cardiac Repair

4.10 Macrovascular Disease – Therapeutic Potential of cEPCs: Reduction Methods for CV Risk

4.11 Bystolic’s generic Nebivolol – positive effect on circulating Endothelial Proginetor Cells endogenous augmentation

4.12 Heart Vasculature – Regeneration and Protection of Coronary Artery Endothelium and Smooth Muscle: A Concept-based Pharmacological Therapy of a Combination Three Drug Regimen including THYMOSIN

Summary to Part Two

Epilogue to Volume Four

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Electronic Proceedings for 10th US-India BioPharma & Healthcare Summit, June 2, 2016, Marriott Cambridge, MA

 

Curator: Aviva Lev-Ari, PhD, RN

 

LIVE — 9AM-noon US-India BioPharma & Healthcare Summit, June 2, 2016, Marriott Cambridge, MA

https://pharmaceuticalintelligence.com/2016/06/02/live-9am-noon-us-india-biopharma-healthcare-summit-june-2-2016-marriott-cambridge-ma/

 

LIVE 11:45AM – 2:40PM US-India BioPharma & Healthcare Summit, June 2, 2016, Marriott Cambridge, MA

https://pharmaceuticalintelligence.com/2016/06/02/1145am-240pm-us-india-biopharma-healthcare-summit-june-2-2016-marriott-cambridge-ma/

 

LIVE 3:15PM – 5:00PM US-India BioPharma & Healthcare Summit, June 2, 2016, Marriott Cambridge, MA

https://pharmaceuticalintelligence.com/2016/06/02/315pm-500pm-us-india-biopharma-healthcare-summit-june-2-2016-marriott-cambridge-ma/

 

 

 

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FDA Approved Roche CMV Test for Hematopoietic Stem Cell Transplants

Reporter: Aviva Lev-Ari, PhD, RN

 

Roche CMV Test for Hematopoietic Stem Cell Transplants Gets FDA OK

NEW YORK (GenomeWeb) – Roche today announced that that the US Food and Drug Administration has approved the firm’s cytomegalovirus (CMV) test for use with hematopoietic stem cell transplant recipients.

The real-time PCR-based Cobas AmpliPrep/Cobas TaqMan CMV test is the first to received FDA approval for that use case and is now available for all transplant patients, Roche said in a statement. The firm added that the test is already the leading in vitro diagnostic for solid organ transplant recipients in the US.

The CMV assay assists in the management of transplant recipients undergoing anti-CMV therapy. It detects viral DNA to help assess virological response to treatment, and runs on Roche’s Cobas AmpliPrep/Cobas TaqMan system.

“Cytomegalovirus is the most important viral infection in hematopoietic stem cell transplant patients,” Uwe Oberlaender, head of Roche Molecular Diagnostics, said in a statement. “With this new FDA approval, hematopoietic stem cell transplant clinicians and patients have another tool to help fight CMV.”

The Cobas CMV assay also conforms to the World Health Organization International Standard, enabling labs worldwide to compare results.

The FDA awarded Roche premarket approval for the test in 2012. In 2014,  Roche landed CE marking for its CMV viral load assay for the Cobas 6800/8800 PCR platforms.

SOURCE

https://www.genomeweb.com/molecular-diagnostics/roche-cmv-test-hematopoietic-stem-cell-transplants-gets-fda-ok?utm_source=SilverpopMailing&utm_medium=email&utm_campaign=Daily%20News:%20Roche%20CMV%20Test%20for%20Hematopoietic%20Stem%20Cell%20Transplants%20Gets%20FDA%20OK%20-%2005/25/2016%2011:25:00%20AM

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Embryonic Stem Cell differentiation

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Plant Homeo Domain Finger Protein 8 Regulates Mesodermal and Cardiac Differentiation of Embryonic Stem Cells Through Mediating the Histone Demethylation of pmaip1

Yan Tang1, Ya-Zhen Hong1, Hua-Jun Bai1, Qiang Wu1, Charlie Degui Chen2, Jing-Yu Lang1, Kenneth R. Boheler3 and Huang-Tian Yang1,4,*

STEM CELLS: 18 APR 2016     http://dx.doi.org:/10.1002/stem.2333

Histone demethylases have emerged as key regulators of biological processes. The H3K9me2 demethylase plant homeo domain finger protein 8(PHF8), for example, is involved in neuronal differentiation, but its potential function in the differentiation of embryonic stem cells (ESCs) to cardiomyocytes is poorly understood. Here, we explored the role of PHF8 during mesodermal and cardiac lineage commitment of mouse ESCs (mESCs). Using a phf8 knockout (ph8-/Y) model, we found that deletion ofphf8 in ESCs did not affect self-renewal, proliferation or early ectodermal/endodermal differentiation, but it did promote the mesodermal lineage commitment with the enhanced cardiomyocyte differentiation. The effects were accompanied by a reduction in apoptosis through a caspase 3-independent pathway during early ESC differentiation, without significant differences between differentiating wide-type (ph8+/Y) and ph8-/Y ESCs in cell cycle progression or proliferation. Functionally, PHF8 promoted the loss of a repressive mark H3K9me2 from the transcription start site of a proapoptotic gene pmaip1 and activated its transcription. Furthermore, knockdown ofpmaip1 mimicked the phenotype of ph8-/Y by showing the decreased apoptosis during early differentiation of ESCs and promoted mesodermal and cardiac commitment, while overexpression of pmaip1 or phf8 rescued the phenotype of ph8-/Y ESCs by increasing the apoptosis and weakening the mesodermal and cardiac differentiation. These results reveal that the histone demethylase PHF8 regulates mesodermal lineage and cell fate decisions in differentiating mESCs through epigenetic control of the gene critical to programmed cell death pathways. Stem Cells2016

 

Significance Statement

Embryonic stem cells (ESCs) have the unique ability to differentiate into derivatives of all three germ layers both in vitro and in vivo. Thus, ESCs provide a unique model for the study of early embryonic development. We report here previously unrecognized effects of histone demethylase plant homeo domain finger protein 8 (PHF8) on mesodermal and early cardiac differentiation. This effect is resulted from the regulation of PHF8 on apoptosis through activating the transcription of pro-apoptotic gene pmaip1. These findings extend the knowledge in understanding of the epigenetic modification in apoptosis during ESC differentiation and of the link between apoptosis and cell lineage decision as well as cardiogenesis.

 

Embryonic stem cells (ESCs) have the unique ability to differentiate into derivatives of all three germ layers both in vitro and in vivo. Due to this plasticity, mechanisms controlling cell autonomous and regulatory events critical to in vivo mammalian development have benefitted from the in vitro study of differentiating ESCs [1, 2]. Early embryogenesis and cavity formation as well as early ESC differentiation, for example, are accompanied by a reduction in proliferation and increased apoptosis [3-5]. Withdrawal of leukemia inhibitory factor (LIF) from mouse embryonic stem cells (mESCs) cultivated in vitro causes approximately 20%-30% of the cells to die by spontaneous (constitutive) apoptosis [4, 5]. This occurs secondary to the induction of cleaved caspase 3 [3] and apoptosis-inducing factor (AIF)-complex proteins [6]. Blockade of spontaneous apoptosis in vitro by a p38 mitogen-activated protein kinase (MAPK) inhibitor alters the differentiation markers and increases the abundance of both antiapoptotic proteins (Bcl-2, Bcl-XL) and Ca2+-binding proteins [4, 7]. In addition, Ca2+ released from type 3 inositol 1, 4, 5-trisphosphate receptors (IP3R3) negatively regulates this apoptotic response, which in turn modulates the mesodermal lineage commitment of early differentiating mESCs [5]. These findings explain, in part, how apoptosis contributes to specific lineage commitment during early development. However, in contrast to the relatively advanced knowledge of signaling pathways [8], little is known about the contribution of epigenetic regulators, especially, histone lysine demethylases (KDMs), in the regulation of apoptosis during ESC differentiation and how the affected programmed cell death by KDMs contributes to the lineage commitment.

Epigenetic regulators and dynamic histone modifications by KDMs are emerging as important players in ESC fate decisions [9]. Histone modifications coordinate transient changes in gene transcription and help maintaining differential patterns of gene expression during differentiation [10-13]. The molecular and biological functions of many KDMs, however, remain enigmatic during ESC differentiation. PHF8, an X-linked gene encoding an evolutionarily conserved histone demethylase harboring an N-terminal plant homeo domain (PHD) and an active jumonji-C domain (JmjC), is able to catalyze demethylation from histones [14, 15]. It is actively recruited to and enriched in the promoters of transcriptionally active genes [14], and it functions to maintain the active state of rRNA through the removal of the repressive H3K9me2 methylation mark at the active rRNA promoters. Mutation of PHF8 is associated with X-linked mental retardation with cleft lip/cleft palate in human [16-18]. Knockdown of phf8 in mouse embryonic carcinoma P19 cells impairs neuronal differentiation [19] and leads to brain defects in zebrafish by directly regulating the expression of the homeo domain transcription factor MSX1/MSXB [20]. However, the precise function of PHF8 in the regulation of lineage differentiation derived from other germ layers remains to be identified.

Here, we report previously unrecognized effects of the PHF8 histone demethylase on germ layer commitment and differentiation of mESCs. The results are based on an assessment of early steps of differentiation to mesodermal lineages and cardiomyocytes using phf8 knockout (phf8-/Y) and wild-type (phf8+/Y) mESCs. The data show that PHF8 regulates gene transcription of a proapoptotic gene pmaip1 (also named Noxa) [21]. Activation or repression of pmaip1 controlled by PHF8 ultimately determines mESC lineage commitment through the regulation of caspase 3-independent apoptosis during mesodermal and cardiac differentiation. Our data reveal that PHF8-mediated the demethylation of histone proteins coordinates ESC lineage commitment through the regulation of apoptosis in early differentiating ESCs.

 

Deletion of phf8 Promotes Mesodermal and Cardiac Lineage Commitment

The PHF8 protein was detectable in undifferentiated ESCs, but its abundance significantly increased within one day of LIF withdrawal. Then it gradually decreased to a level at day 5 lower than that observed in the undifferentiated ESCs (Fig. 1A).    http://onlinelibrary.wiley.com/store/10.1002/stem.2333/asset/image_t/stem2333-fig-0001-t.gif

 

Figure 1. Plant homeo domain finger protein 8 (PHF8) regulates the mesodermal and early cardiac differentiation of mouse embryonic stem cells (mESCs). (A): Western blot analysis of PHF8 expression in undifferentiated and differentiating ESCs. n = 3. (B): quantitative RT-PCR (qRT-PCR) analysis of pluripotency markers nanog, rex1, sox2, and oct4. n = 8. (C): qRT-PCR analysis of gene expression of pluripotency marker oct4; early mesodermal markers brachyury (T), gsc, eomes, and mesp1; cardiovascular progenitor markers flk-1 and nrp1; and the cardiac transcription factors hand1, tbx5, and mef2c during ESC differentiation. n = 5. (D): qRT-PCR analysis of the early ectodermal markersnestin and fgf5 during ESC differentiation. n = 3. (E): qRT-PCR analysis of early endodermal markers afp, foxa2, sox17, and gata4 during ESC differentiation. n = 3. Data are presented as mean ± SEM *, p < .05; **, p < .01; ***, p < .001 compared with the corresponding phf8+/Y value.

To determine the significance of phf8 gene expression on ESC fate decision, we knocked out the X-chromosome-encoded phf8 gene in one allele of male SCR012 ESCs by deletion of exons 7 and 8 through Cre-mediated recombination (Supporting Information Fig. S1A). Gene inactivation was confirmed by the lack of Phf8 mRNA and PHF8 protein expression in these targeted ESCs (Supporting Information Fig. S1B). Transcripts for pluripotency marker genes nanog, rex1 (zfp42), sox2, and oct4 (pou5f1) were not significantly different between phf8+/Y and phf8-/Y ESCs (Fig. 1B). No significant difference was observed in cell morphology (Supporting Information Fig. S1C) of undifferentiated phf8+/Y and phf8-/Y ESCs or in alkaline phosphatase activity (Supporting Information Fig. S1D). Immunofluorescence staining confirmed that the expression of pluripotency marker SOX2 and SSEA-1 did not differ between the phf8+/Y and phf8-/Y ESCs (Supporting Information Fig. S1E). These results indicate that phf8 may be dispensable for normal growth and maintenance of mESCs.

We then analyzed the role of PHF8 in the mesodermal and cardiac lineage commitment. By microarray analysis of differentiating phf8+/Y and phf8-/Y cells from days 0, 1, to 3.5, we found a significant decrease in transcripts for pluripotency markers, accompanied by a significant increase in transcripts for ectoderm, mesoderm and endoderm, while in phf8-/Y cells some transcripts for mesodermal and cardiac lineage commitment were significantly enhanced compared with those in phf8+/Y cells (Supporting Information Fig. S2A). These differentiation-dependent changes in transcript abundance were confirmed by qRT-PCR for early mesodermal markers brachyury (T) [28], goosecoid (gsc),eomes[29], and mesp1[30], cardiovascular progenitor marker flk-1[31, 32] and neuropilin 1 (nrp1) [33]. Early cardiac transcription factors, including myocyte enhancer factor 2C (mef2c) [34], hand1[35], and tbx5[36, 37] were also up-regulated in phf8-/Y cells at differentiation day 5, while no difference in the expression levels of pluripotent markersoct4 (Fig. 1C), rex1, and nanog (Supporting Information Fig. S2B) were detected between phf8+/Y and phf8-/Y cells at the time points examined.

Because mESCs can differentiate into all three germ layers, we also examined whether phf8 affected ectodermal and endodermal differentiation. qRT-PCR analysis did not show any significantly difference in the expression of early ectodermal markers nestin and fgf5 between the phf8+/Y and phf8-/Y cells (Fig. 1D). Moreover, in the induced early ectodermal differentiation system [23], the expression of ectodermal markers nestin, fgf5, and pax6 were comparable between the phf8+/Y and phf8-/Y cells (Supporting Information Fig. S3A). Besides, the expression of endodermal markers afp, foxa2, sox17, and gata4 were not significantly different between the phf8+/Y and phf8-/Y cells (Fig.1E). Consistently, the expression of endodermal markers foxa2, sox17, and gata4 were comparable during induced endodermal differentiation [24] between the phf8+/Y andphf8-/Y cells (Supporting Information Fig. S3B). Thus, phf8 appears not to affect early ectodermal and endodermal differentiation.

The increased mesodermal and cardiac marker expressions were associated with a significant increase in the total number of cardiac progenitors and cardiomyocytes in differentiating phf8-/Y cells. By flow cytometry analysis, marked increases in the population of FLK-1 positive (FLK-1+) cells were detected in phf8-/Y cells at differentiation day 3 and day 4 (Fig. 2A). Consistently, the percentage of contracting EBs was higher in phf8-/Y cells than in phf8+/Y cells (Fig. 2B). The transcripts for progenitor marker nrp1, early cardiac transcription factor tbx5, and cardiac specific genes tnnt2, myh6, myl2, and gja1 were higher in phf8-/Y EBs than those in phf8+/Y ones (Fig. 2C). The areas of immunostained EBs positive for the cardiac cytoskeletal and myofilamental proteins α-actinin and TNNT2 were also greater in phf8-/Y than in phf8+/Y EBs (Fig. 2D). Flow cytometry analysis of MYH6+ (Fig. 2E) and TNNT2+ (Fig. 2F) cells at differentiation day 9 further confirmed the increase of cardiomyocytes in phf8-/Y cells. Taken together, these data indicate that the phf8 deletion facilitates the differentiation of mesodermal and cardiac linage commitment.

Figure 2. phf8 deletion promotes cardiac differentiation of mouse embryonic stem cells (mESCs). (A): Left, representative flow cytometry plots showing FLK-1 expression at differentiation day 3 (n = 6), day 4 and day 5 (n = 3 each). Right, the quantification of flow cytometry data. (B): Differentiation profile of cardiomyocytes during embryoid bodies (EB) outgrowth. n = 6. (C): qRT-PCR analysis of ESCs for the expression of cardiac markers at differentiation day 14. n = 3. (D): Immunofluorescence analysis of TNNT2 and α-actinin in day 14 EBs. Scale bars = 400 μm. (E) Flow cytometry analysis of MYH6 positive cells and (F) TNNT2 positive cells in day 9 EBs. n = 3 each. Data are presented as mean ± SEM *, p < .05; **, p < .01; ***, p < .001 compared with the corresponding phf8+/Y value.   http://onlinelibrary.wiley.com/store/10.1002/stem.2333/asset/image_t/stem2333-fig-0002-t.gif

PHF8 Inactivation Increases Cell Viability but not Proliferation of the Differentiating ESCs

Differentiation of both phf8+/Y and phf8-/Y ESCs via EB formation produced normal round shaped EBs but, by day 3, phf8-/Y EBs were larger than those generated from phf8+/YESCs, and the size differences were visibly obvious at differentiation days 5 and 7 (Fig. 3A). Although no significant differences in cell viability could be demonstrated between undifferentiated phf8+/Y and phf8-/Y ESCs (Fig. 3B), the viability of phf8-/Y cells was significantly greater than that in phf8+/Y cells at differentiation days 3 to 7 (Fig. 3C). However, no significant change in BrdU staining was detected by flow cytometry between phf8+/Y and phf8-/Y ESCs at differentiation days 0, 3, or 5 (Fig. 3D). Moreover, no significant difference in the cell cycle distribution between the differentiating Phf8+/Y and Phf8-/Y ESCs was detected, although the percentage of cells in S phase gradually decreased while those in G1 phase increased upon differentiation (Fig. 3E). Knockout of phf8 thus increases cell numbers in the early differentiating ESCs through the improvement of cell viability without changes in cell proliferation or cell cycle progression.

Figure 3. phf8 deletion increases cell viability in differentiating mouse embryonic stem cells (mESCs) without affecting cell proliferation. (A): Left, phase-contrast images of embryoid bodies (EB) morphology during EB formation from ESCs. Scale bar = 200 μm. Right, the diameter of EB formed from ESCs. (B): Cell viability of undifferentiated and (C): differentiating ESCs analyzed by MTT assay for seven consecutive days. n = 3. (D): Flow cytometry analysis of BrdU positive proportion of undifferentiated (n = 4) and differentiating ESCs at day 3 and day 5.n = 5 each. (E): Flow cytometry analysis of cell cycle distribution by propidium iodide (PI) staining at differentiation day 3 (n = 6) and day 5 (n = 3). Data are presented as mean ± SEM *, p < .05; ***, p < .001 compared with the corresponding phf8+/Y value.   http://onlinelibrary.wiley.com/store/10.1002/stem.2333/asset/image_t/stem2333-fig-0003-t.gif

PHF8 Regulates Apoptosis During the Early Stage of Cardiac Lineage Commitment

We then examined whether cell death might account for the differences in the cell viability observed between the differentiating phf8+/Y and phf8-/Y ESCs. In undifferentiated ESCs, no significant difference was demonstrated with Annexin V (an early apoptosis marker) staining, TUNEL assay, total DNA fragmentation or caspase 3 protein cleavage between phf8+/Y and phf8-/Y cells (Fig. 4A–4C, 4E). In contrast, Annexin V staining (Fig. 4A) and TUNEL assay (Fig. 4B) showed significant decreases in the number of apoptotic cells in phf8-/Y ESCs at differentiation days 3 and 5 compared with those in phf8+/Y cells. Genomic DNA fragmentation with a pattern typical for apoptosis was detected in phf8+/Y cells at differentiation days 3 and 5, but it was reduced in phf8-/Y cells at the same time points (Fig. 4C). Moreover, approximately 35% of Annexin V+ cells were present in FLK-1+/phf8+/Y cells at differentiation day 4, whereas only 9% of the cells were Annexin V+ in FLK-1+/phf8-/Y cells (Fig. 4D). The ratio of TUNEL+ to either NESTIN+ (ectoderm) or SOX17+ (endoderm) cells did not differ between the phf8+/Y and phf8-/Y cells (Supporting Information Fig. S3C, S3D). In addition, phf8+/Y ESCs at differentiation days 3 and 5 increased the caspase 3 cleavage (Fig. 4E, upper and lower left panels) and the ratio of cleaved caspase 3 to total caspase 3 protein (Fig. 4E, lower right panel). Unexpectedly, the ratio of cleaved caspase 3 to total caspase 3 in phf8-/Y ESCs did not significantly differ from that observed in phf8+/Y ones. Consistently, a significant enhancement of the downstream target PARP1 cleavage [38, 39] was observed at differentiation days 3 and 5, but it was comparable between the phf8+/Y andphf8-/Y cells (Fig. 4F). These data suggest that the cell death associated with phf8 function does not operate through the conventional caspase 3-mediated apoptosis.

Figure 4. Plant homeo domain finger protein 8 (PHF8) regulates apoptosis during the early mouse embryonic stem cells (mESC) differentiation. (A): Left, representative flow cytometry plots showing Annexin V (x-axis), and PI (y-axis) staining in ECSs at differentiation day 0 (n = 4), day 3 (n = 3) and day 5 (n = 7). Right, the quantification of flow cytometry data. (B): Flow cytometry detection of apoptotic responses of TUNEL positive cells at differentiation day 0 (n = 3), day 3 (n = 4), and day 5 (n = 4). (C): DNA laddering analysis at differentiation days 0, 3, and 5. n = 6 each. (D): Cells double stained with FLK-1 and Annexin V were analyzed by flow cytometry at differentiation day 4. n = 3. (E): Western blot analysis of caspase 3 during the mESC differentiation. β-actin was used as a loading control. n = 4. (F): Western blot analysis of PARP1 expression during the differentiation. β-actin was used as a loading control. n = 4. Data are presented as mean ± SEM *, p < .05; ***, p < .001 compared with the corresponding phf8+/Yvalue; #, p < .05; ##, p < .01 compared with the corresponding d0 value.  http://onlinelibrary.wiley.com/store/10.1002/stem.2333/asset/image_t/stem2333-fig-0004-t.gif

pmaip1 is a Direct Target Gene of PHF8 in the Early Differentiating ESCs

To understand how PHF8 might regulate apoptosis during early ESC differentiation, we compared the profiles of apoptosis-related gene transcripts in undifferentiated and early differentiating phf8+/Y and phf8-/Y ESCs using gene expression microarrays. Among the apoptosis-related genes, the transcript to pmaip1, a proapoptotic Bcl-2 family member crucial in fine-turning the cell death decision [21, 40-42], was markedly increased during early differentiation of phf8+/Y cells but it was reduced in phf8-/Y cells at differentiation days 1 and 3.5 (Fig. 5A). These expression patterns were confirmed by qRT-PCR during cardiac differentiation (Fig. 5B), and the results were consistent with the apoptotic pattern observed during the early ESC differentiation (Fig. 4A–4C). In addition, qRT-PCR analysis showed that the expression of pmaip1 did not show any significant difference between the phf8+/Y and phf8-/Y cells during the induced ectodermal (Supporting Information Fig. S3E) or endodermal (Supporting Information Fig. S3F) differentiation.

Figure 5. pmaip1 is a direct target gene of plant homeo domain finger protein 8 (PHF8) in mouse embryonic stem cells (mESCs). (A): Microarray gene expression heat map depicting the expression of apoptosis-related genes at differentiation days 0, 1 and 3.5 in phf8+/Y and phf8-/Y ESCs. The expression values in log2 scale were calculated and presented on the heat map with red representing highly abundant transcripts and green representing poorly abundant transcripts. n = 3. (B): qRT-PCR analysis of pmaip1 during the ESC differentiation. (C): ChIP assay of PHF8 around the TSS of pmaip1 in phf8+/Y andphf8-/Y ESCs at differentiation days 0 and 3. n = 4 each. (D): Western blot analysis of H3K9me2 and H3 in phf8+/Y and phf8-/Y ESCs during the differentiation. H3 was used as a loading control. n = 9. (E): H3K9me2 staining inphf8+/Y and phf8-/Y embryoid bodies (EBs) at differentiation day 1. Scale bars = 25 μm. (F): ChIP assay of H3K9me2 around the TSS of pmaip1 in phf8+/Y andphf8-/Y ESCs at differentiation day 3. n = 4. Data are presented as mean ± SEM. *, p < .05; **, p < .01; ***, p < .001 compared with the corresponding phf8+/Y value or d0.  http://onlinelibrary.wiley.com/store/10.1002/stem.2333/asset/image_t/stem2333-fig-0005-t.gif

A direct link between the PHF8 and pmaip1 was then confirmed by ChIP analysis. We detected the endogenous binding of PHF8 at the transcription start site (TSS, from −45 bp to 104 bp) of pmaip1 in phf8+/Y ESCs and determined that binding was enhanced at differentiation day 3. The binding of PHF8 was not detectable above the IgG control levels in phf8-/Y cells (Fig. 5C). Global methylation (H3K9me2 normalized to H3) was unchanged at differentiation days 3 and 5, but it was significantly enhanced at differentiation day 1 in phf8-/Y cells (Fig. 5D). The augmentation of H3K9me2 methylation in phf8-/Y ESCs was then confirmed by immunostaining at differentiation day 1 (Fig.5E). An increase in the repressive mark of H3K9me2 was also observed at the TSS of pmaip1 in the early differentiating phf8-/Y ESCs (Fig. 5F), indicating that the PHF8 demethylase activity is actively involved in the regulation of pmaip1 gene.

Transient Knockdown of pmaip1 Decreases Apoptosis and Promotes Mesodermal and Cardiac Differentiation

To clarify the role of pmaip1 in mESC differentiation, we transfected specific siRNAs against pmaip1 (si-Pmaip1) into phf8+/Y ESCs followed by EB formation. The negative control siRNA (si-NC) did not alter pmaip1 transcript levels compared with untreated (NT) cells, while si-Pmaip1 significantly inhibited pmaip1 transcripts by 74%-76% at differentiation days 0 and 1 (Fig. 6A-a). si-Pmaip1 cells had fewer TUNEL+ cells compared with the NT and si-NC cells at differentiation day 3 in both phf8+/Y and phf8-/Y cells (Fig. 6A-b). We then examined whether the pmaip1 knockdown influences mesodermal and early cardiac differentiation. As shown in Figure 6B, the apoptosis of FLK-1+ cells was significantly decreased in si-Pmaip1 mESCs (Fig. 6B). The expression of T and gsc as well as nrp1 and flk-1 were increased in si-Pmaip1 cells compared with those in NT and si-NC cells at differentiation day 3. In addition, the expression of cardiac transcript factors mef2c and tbx5 was up-regulated at differentiation day 5, and myh6 andtnnt2 were up-regulated at differentiation day 9 (Fig. 6C). We also transfected si-Pmaip1 into phf8-/Y ESCs. The expression of pmaip1 was downregulated at differentiation day 0 and day 1 in phf8-/Y ESCs with si-Pmaip1 (Supporting Information as Fig. S4A-a), accompanied by a decrease in TUNEL+ cells compared with NT and si-NC (Fig. 6A-b), while Annexin V remained unchanged (Supporting Information Fig. S4A-b). The expression of nrp1 and flk1 did not significantly change in phf8-/Y ESCs with si-Pmaip1 at differentiation day 3, while mef2c was upregulated at differentiation day 5, and myh6 was upregulated at differentiation day 9 (Supporting Information as Fig. S4B). These results suggest that downregulation of pmaip1 in phf8-/Y ESCs may not lead to as robust of a phenotype as it did in phf8+/Y ESCs. This difference is likely due to the level ofpmaip1 during early differentiation of phf8-/Y ESCs was already decreased to a low level similar to that observed in the undifferentiated cells (Fig. 5B). Taken together, these data demonstrate that the decreased apoptosis via down-regulation of pmaip1 contributes, at least partially, to the phf8-/Y-facilitated mesodermal and cardiomyocyte commitment.

Figure 6. Plant homeo domain finger protein 8 (PHF8) regulates the mesodermal and cardiac differentiation through pmaip1. (A-a): qRT-PCR analysis of thepmaip1 expression in phf8+/Y ESCs after being transiently transfected with si-NC or si-Pmaip1. n = 4. (A-b): Apoptosis cells were quantified by flow cytometry analysis of TUNEL assay at differentiation day 3 in phf8+/Y and phf8-/Y ESCs after transient transfection with si-NC or si-Pmaip1. n = 3. (B): Cells double stained with FLK-1 and Annexin V were analyzed by flow cytometry at differentiation day 4. n = 4. (C): qRT-PCR analysis of the expression of T, gsc, flk-1, nrp1, tbx5, mef2c, myh6, and tnnt2 in phf8+/Y ESCs after transient transfection with si-NC or si-Pmaip1. n = 5. (D): Flow cytometry detection of TUNEL positive cells at differentiation day 3, Annexin V positive cells and double stained FLK-1 and Annexin V at differentiation day 4 in phf8-/Y, phf8-NC-/+, phf8-pmaip1-/+, and phf8-hPHF8-/+ mouse embryonic stem cells (mESCs). n = 4. (E): qRT-PCR analysis of the expression of T, gsc, flk-1, nrp1, tbx5, mef2c, myh6, and tnnt2 in phf8-/Y, phf8-NC-/+, phf8-pmaip1-/+, and phf8-hPHF8-/+ mESCs. n = 3. Data are presented as mean ± SEM. *, p < .05; **, p < .01; ***, p < .001 compared with the corresponding phf8+/Y or phf8-/Y value.
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Overexpression of pmaip1 or hPHF8 in phf8-/Y ESCs Increases Apoptosis and Weakens Mesodermal and Cardiac Differentiation

To further determine whether PHF8 contributes to mesoderm and cardiac cell commitment through the regulation of apoptosis via targeting pmaip1, we rescued the expression of pmaip1 and phf8 in phf8-/Y ESCs by generating pmaip1-ovexpressing phf8-/Y mESCs (phf8-pmaip1-/+ mESCs) and hPHF8-overexpressing phf8-/Y mESCs (phf8-hPHF8-/+ mESCs). The qRT-PCR analysis confirmed that the expression of hPHF8 or pmaip1 was significantly upregulated in the respective overexpressing cell lines (Supporting Information Fig. S4C). The expression of pmaip1 in undifferentiated phf8-/Y mESCs was not affected by hPHF8 overexpression. However, Pmaip1 transcripts increased by differentiation day 3 in overexpressing cells (Supporting Information Fig. S4D), indicating that PHF8 does regulate the expression of pmaip1 during differentiation. Both TUNEL and Annexin V analysis revealed significant increases of apoptosis in phf8-pmaip1-/+ and phf8-hPHF8-/+ mESCs compared with the phf8-/Y andphf8-NC-/+ mESCs at differentiation day 3 or day 4, accompanied by a higher apoptosis ratio in FLK-1+ cells (Fig. 6D). Moreover, the expression of T and gsc as well as nrp1and flk-1 were significantly decreased in phf8-pmaip1-/+ and phf8-hPHF8-/+ mESCs at differentiation day 3, followed by a down-regulation of mef2c and tbx5 at differentiation day 5, and myh6 and tnnt2 at differentiation day 9 (Fig. 6E). In addition, TUNEL analysis showed no changes in the apoptotic responses either through knockout or overexpression of phf8 compared with the corresponding wild-type cells or phf8+/Y cells during induced ectodermal differentiation (Supporting information Fig. S4E). These data are consistent with a regulatory role of phf8 on mesodermal and cardiac differentiation through targeting of pmaip1

Discussion

This is the first study to unravel a regulatory role of histone demethylase in the differentiation of ESCs through the control of apoptosis and subsequent effects on cell lineage commitment. The role of PHF8 in the regulation of ESC differentiation to the mesodermal lineage and cardiac differentiation is supported by selective changes in RNA markers for mesodermal lineages, and an increase in cardiomyocyte progenitors and cardiomyocytes (Figs. 1C, 2C). Moreover, deletion of phf8 specifically inhibits apoptosis of Flk-1+ mesodermal cells with a concomitant reduction in Annexin V+ staining (Fig. 4D) and cardiac differentiation (Fig. 2B–E), while the ratio of TUNEL+ to either NESTIN+(ectodermal cells) or SOX17+ (endodermal cells) cells does not differ between the phf8+/Y and phf8-/Y lines (Supporting Information Fig. S3C, S3D). Consistently, the proportion of early apoptotic cells (Annexin V+) in pmaip1-knockdown (Fig. 6B) is also decreased, while pmaip1-overexpression or hPHF8-overexpression in phf8-/Y cells increase the proportion of TUNEL+ and Annexin V+ cells simultaneously with a reduction in mesodermal and cardiac differentiation (Fig. 6D, 6E). These findings indicate that the PHF8 functions, at least partially, through regulation of apoptosis.

It is well known that the regulation of apoptosis is of critical importance for proper ESC differentiation and embryo development [8, 43]. ESC differentiation is regulated by apoptosis induced by MAPK activation [7] and IP3R3-regulated Ca2+ release [5]. Previously only histone 3 lysine 4 methyltransferase MLL2 had been shown to activate the antiapoptotic gene bcl2 to inhibit apoptosis during ESC differentiation [44]. The data presented, here, extends and reveals the importance of epigenetic controls in the activation of proapoptotic gene associated with ESC differentiation.

Mesodermal and cardiac differentiation have been shown to be regulated by the histone demethylase ubiquitously transcribed tetratricopeptide repeat, X chromosome (UTX)[13, 45] and jumonji domain–containing protein 3 (JMJD3) [12] through transcriptional activation of mesodermal and cardiac genes. These findings together with those presented in this paper support the critical role of histone demethylases in lineage commitment through regulatory mechanisms that control the expression of core lineage specific transcription factors and apoptotic genes. The decrease in apoptosis through deletion of phf8 can be attributed to the maintenance of repressive H3K9me2 mark on the TSS of pmaip1 after phf8 deletion, resulting in a ∼70% downregulation of pmaip1 at differentiation day 3 in the phf8-/Y cells (Fig. 5B). The pro-apoptotic gene pmaip1 is, therefore, epigenetically regulated by the histone demethylase, which subsequently affects the mesodermal and cardiac differentiation.

PMAIP1 is a Bcl2 homology domain 3 (BH3)-only protein that acts as an important mediator of apoptosis [46]. Its expression is regulated transcriptionally by various transcription factors and, when present, it acts to promote cell death in a variety of ways [21] including caspase 3 dependent [47] and independent apoptosis [48] and autophagy [40]. Here, we find that PHF8 and its regulation on the pmaip1 promote DNA fragmentation and cell death most likely through a caspase 3-independent pathway. This conclusion is based on the observation that neither the ratio of cleaved caspase 3 to total caspase 3 [49, 50] nor PARP1, a downstream target of caspase 3, is significantly affected. While this may be explained as the inhibitor of apoptosis proteins can counteract the function of caspase 3 [51, 52], the exact mechanisms we observed here need to be further explored.

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