Nihal Tümer, Ph.D.
Phone: 352-376-1611 ext. 6575
Office: VAMC Box 182
Publications: Search PubMed
Sympathetic nervous system activity and blood pressure increase with age, and this elevated blood pressure is a major contributor to cardiovascular diseases in the elderly. We are examing the role of oxidative stress in age-related sympathetic nervous activation and blood pressure elevation. Oxidative stress has been implicated in the aging process in various tissues including the central nervous system due to an imbalance between production and elimination of free radicals. Our data suggests that angiotensin II plays an important role in the activation of sympathetic pathways as well as reactive oxygen species production.
Our second focus involves interventions to increase physical activity levels in aged rats. With age there is both an increase in adiposity and a decrease in physical activity. Moreover, physical activity decreases with increasing body weight independent of age, and decreases in physical activity lead to obesity, thus age, obesity and physical activity are interlinked. We are examining whether gene delivery interventions with leptin and pro-opiomelanocortin (POMC), by reducing body weight, will increase physical activity levels. We discovered that POMC overexpression, apparently independent of the weight loss, enhances physical activity, and current studies are focused on the underlying mechanism.