The OFAS Team
David Orentreich, MD
David Orentreich received his MD degree from Columbia College of Physicians and Surgeons in 1980. He became a diplomat of the National Board of Medical Examiners in 1981 and American Board of Dermatology in 1984. He joined the Orentreich Medical Group, LLP (OMG, LLP) as a Partner in1984. In 1987, he was appointed Assistant Clinical Professor in the Department of Dermatology of the Ichan School of Medicine at Mount Sinai and Assistant Attending at the Mount Sinai-New York University Hospitals Health System. Concurrently, he joined Dr. Norman Orentreich as Consultant and Guiding Dermatologist for Clinique Laboratories, LLC. In clinical practice, he helped develop and create procedural innovations and maintenance treatments that were recognized both nationally and internationally. He continues to treat skin disorders with a vast array of modern technologies and medicines, including the latest lasers, fillers, neurotoxins, and skin care products.
Having always been interested in research, he authored and co-authored a multitude of medical journal and book chapter publications within the fields of general dermatology, injectable fillers, scar revision, hair, and biomedical research. After becoming Co-Director of the Orentreich Foundation for the Advancement of Science (OFAS, Inc.) in 2007, he began focusing his interest in the area of dietary sulfur amino acid restriction. As Director, he is closely involved in the activities of OFAS and regularly attends meetings with scientific staff to oversee research.
Jay A. Zimmerman, Ph.D.
Deputy Director of Research
Dr. Zimmerman received his Ph.D. in Endocrinology from Rutgers University in 1973. His post-doctoral research at the Masonic Medical Research Laboratory focused on experimental gerontology. In 1975 he was appointed as an Assistant Professor at St. John’s University, Queens, NY. During the ensuing 45 years he rose to the rank of Full Professor, served as the long-time Chair of the Department of Biological Sciences, and administered over twelve million dollars in grants that were awarded to him. During this time, Dr. Zimmerman was also a consultant to OFAS, and co-authored the first scientific publication demonstrating the life-extending effects of dietary methionine restriction.
Gene P. Ables, Ph.D.
Dr. Ables received his degree of Doctor of Veterinary Medicine from the University of the Philippines. He then obtained his PhD from Hokkaido University (Japan). His post-doctoral research in Preventive Medicine and Nutrition at Columbia University focused on liver lipid metabolism. In 2006, he was appointed Associate Research Scientist at the Columbia University Medical Center. Dr. Ables joined OFAS in April 2011 as a Senior Scientist, and in 2015 he was appointed Associate Science Director. He leads staff in investigations of the methionine-restricted diet’s effects on metabolism, cancer, and epigenetics.
Jay E. Johnson, Ph.D.
Dr. Johnson received his doctorate in Molecular Biology from Case Western Reserve University (Cleveland, OH). His post-doctoral work at Fox Chase Cancer Center (Philadelphia, PA) used a liposarcoma model system to investigate the maintenance of telomeres, important nucleoprotein structures with roles in aging and cancer. Dr. Johnson then joined the University of Pennsylvania (Philadelphia), where his early work explored cellular defects in patients with Werner and Bloom’s syndromes, genetic diseases characterized by accelerated aging and cancer predisposition. Dr. Johnson’s recent work has focused on exploring the mechanistic basis of the benefits of methionine restriction in S. cerevisiae and cultured mouse and human cells.
Sailendra N. Nichenametla, Ph.D.
Dr. Nichenametla received his PhD in Integrative Biosciences from Pennsylvania State University (Hershey, PA) under OFAS consultant Dr. John Richie. He studies how genetics and the environment—diet, in particular—shape health. During graduate and postgraduate training, he investigated how bioactive compounds in milk, berries, and dietary fiber can affect diseases such as colon cancer and metabolic syndrome. While training for his PhD, he investigated how genetic variation in humans alters an individual’s capacity to combat oxidative stress and risk for cancers. He is currently studying biochemical and molecular mechanisms that lead to lifespan extension and other benefits induced by methionine restriction.
Zhen Dong, DrPH
Affiliated Assistant Scientist
Dr. Dong received her degree of Doctor of Public Health from the Penn State College of Medicine. Her doctoral research focused on nutritional epidemiology. In 2017, she began working with OFAS as an intern and joined as a Scientist in July 2019. She brings experience in designing and conducting both retrospective and prospective observational studies, spanning ecological, cross-sectional, case-control, and multi-center cohort studies, in various chronic disease areas. In addition to her work at OFAS, she is currently an Adjunct Associate Professor of Public Health at Penn State. Dr. Dong’s recent work has focused on exploring the associations between consumption of sulfur amino acids and human chronic diseases, including cardiovascular diseases, diabetes, and cancer.
Board of Scientific Advisors
Arthur J.L. Cooper, PhD
Professor of Biochemistry and Molecular Biology, New York Medical College
PhD, Weill Medical College of Cornell University
Research interests include amino acid, sulfur, and energy metabolism; vitamin B6-containing enzymes; bioactivation (toxification) mechanisms; transglutaminases (protein cross linking enzymes); and neurodegenerative diseases.
Mark C. Horowitz, PhD
Professor of Orthopaedics and Rehabilitation; Vice Chair for Research Education & Training, Yale University School of Medicine
PhD, SUNY Upstate Medical Center
Research interests include osteoimmunology; osteoblasts; osteoclasts; adipocytes; bone remodeling; mesenchymal stem cell differentiation; B cell transcription factors and bone
Sulli J. Popilskis, DVM
Asst Professor of Clinical Anesthesiology and Physiology, New York Medical College
DVM, Lithuanian Veterinary Academy