Thomas P. Bersot, M.D., Ph.D.
Areas of Investigation
The activities of the Outreach Program include patient care, teaching, and research related to blood lipid (cholesterol) disorders and coronary heart disease (CHD) prevention. Patient care is delivered through the Gladstone Lipid Clinic, which also serves as a demonstration clinic for teaching students, residents, and fellows of the UCSF Schools of Medicine and Pharmacy. The Gladstone Lipid Disorders Training Center is an educational program for postgraduate healthcare professionals. Our research focuses on the causes of low levels of high density lipoprotein cholesterol (HDL-C).
Lifestyle (diet, exercise) and genetic factors account for the variability in HDL-C levels. In a epidemiological survey of over 10,000 Turks, we have shown that HDL-C levels are 10–15 mg/dl lower in Turkish men and women than in persons of western European ancestry. Our studies have also shown that the HDL-C levels of Turkish children are similar to those of American and western European children. At puberty, however, the HDL-C levels in Turks decrease to the levels seen in adults. The low HDL-C levels in Turkish adults are associated with a 20–30% increase in the activity of the liver enzyme hepatic lipase. Currently, we are investigating genetic variability in the response of hepatic lipase gene expression to dietary intake of fat and carbohydrate. We are studying hormonal and dietary factors that affect HDL-C levels of Turks and attempting to identify genetic factors associated with low HDL-C levels in large Turkish kindreds.
More than half of all patients with CHD in the United States and almost all patients with diabetes have low HDL-C levels. The regulation of HDL-C levels, however, is poorly understood. This is an important area of study because the risk of CHD and stroke, still the leading cause of death in the U.S., is inversely correlated with HDL-C levels.
In our studies of low HDL-C in Turks, we use population-based approaches and genetic analyses. We are characterizing families of Turks with low HDL-C levels with an aim of identifying genetic polymorphisms associated with low HDL-C levels. We are also undertaking studies to identify hormonal changes occurring at puberty that are associated with low HDL-C in postpubertal Turks.
In addition to the instruction of students and physicians in the Gladstone Lipid Clinic, we offer courses for postgraduate physicians in the Lipid Disorders Training Center. A 2 1/2 day mini-fellowship is offered for those seeking comprehensive knowledge about the management of cardiovascular risk factors. A highlight of the mini-fellowships is a one-day demonstration clinic during which course participants see 8–10 patients in the Gladstone Lipid Clinic. One-day Update courses offer guidance about patient management based on the results of recent advances in basic and clinical science.