Nihal Tumer, Ph.D.

Tumer’s research included:

1) Discovery of neuronal mechanisms underlying diet and aged-induced obesity. Obesity is occurring at epidemic rates with frightful health consequences. Her hypothesis was that leptin resistance is an important causative factor in both diet-induced and age-related obesity. Her lab demonstrated that both types of obesity are associated with leptin resistance and this resistance resides within the first order hypothalamic neurons that contain leptin receptors, and they provided strong evidence that the leptin receptor-signaling cascade is impaired. One current area of focus is to restore leptin receptor function with gene delivery/programmed of the leptin in a circadian/intermittent fashion to specific brain regions. A second area of focus is the role of specific dietary components such as fat or sugar as causative factors in leptin resistance independent of caloric intake or body weight.

2) Chronic consequences of Traumatic Brain Injury (TBI) on cerebrovascular function. One deleterious consequence of brain injury is cerebral vascular dysfunction. Human studies indicate that severe traumatic brain injury leads to decreased blood flow and hypoperfusion of the brain tissue. Her lab’s hypothesis was that long-term consequences of TBI are the results of impaired cerebral blood flow and due to chronic oxidative stress and inflammation. Secondarily, they proposed there is elevated sympathetic nervous system activity leading to systemic cardiovascular problems including hypertension.

3) A third area of focus was elucidation of the mechanisms underlying increased hypertension with age. Elevated blood pressure is a major contributor to cardiovascular diseases in the elderly which is the number one killer in the United States. We examined the role of oxidative stress and inflammation in age-related sympathetic nervous activation and blood pressure elevation.