Molecular Medicine Branch
Branch Sections and Chiefs
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Molecular Biology and Genetics Section
Alan Neil Schechter, M.D., Christian B. Anfinsen Distinguished Scientist -
Molecular Cell Biology Section
Constance Tom Noguchi, Ph.D.
Molecular Biology and Genetics Section
Alan Neil Schechter, M.D., Christian B. Anfinsen Distinguished Scientist, Section Chief
The Molecular Biology and Genetics Section now largely focuses on studies of nitric oxide (NO) metabolism, its role in disease pathophysiology, and its potential therapeutic utility. This work evolved from our long-term studies of sickle cell disease pathophysiology and therapy, which continue in several collaborations. We have previously shown that reduction of nitrite and nitrate ions is a major source of bioactive nitric oxide (NO) in the body and that erythrocytes and hemoglobin have major functions in the metabolic pathways of nitrate, nitrite, and NO. We have shown that platelet reactivity is modulated by nitrite reduction to NO in the blood and this may explain differences between arterial and venous blood clotting. Current work is focusing on the fundamental NO pathways in the eye as we have found that lacrimal glands can secrete nitrate from the blood into the tears and are studying, in animals and people, if this pathway accounts for much of the NO levels in the eye, which affect intra-ocular fluid and retinal blood flow. We have also shown that skeletal muscle has very high levels of nitrate, which is reduced to NO during exercise, and can markedly increase blood flow and improve muscle function. This work is continuing in collaboration with exercise investigators at the University of Exeter, UK, but have also pointed to the role of nitrate stored in muscle as being a reservoir for overall mammalian NO-mediated homeostasis. All of these results have immediate nutritional and therapeutic implications.
Molecular Cell Biology Section
Constance Tom Noguchi, Ph.D., Section Chief
The Molecular Cell Biology Section investigates cytokine regulation of metabolism using animal models to identify potential human metabolic response to endogenous erythropoietin and erythropoietin treatment. Erythropoietin binding to its receptor has activity beyond regulation of red blood cell production. Studies of erythropoietin activity in animal models include regulation of glucose metabolism, effects on heart health, modulation of bone formation, metabolic and inflammatory response to high fat diet-induced obesity in adipose tissue and brain, modification of lipid stores in fat and skeletal muscle, and sex and age dependent non-erythroid activity. Section members have recently shown that erythropoietin regulates expression of lipid metabolism associated genes in white adipose tissue via transcription factor RUNX1 that directly inhibits lipogenic gene expression and increases lipolytic gene expression. A new area of research is erythropoietin regulation of fat and glucose metabolism associated with fatty liver disease mediated by modulation of bile acid associated signaling pathway. Non-erythroid tissue specific erythropoietin activity provides the potential for erythropoietin to affect tissue maintenance or repair and metabolic response.