Dr. Mietus-Snyder will release her findings in detail during her presentation at the spring meeting of the American Physiological Society (APS), being held in San Francisco, CA February 20-23, 2002.
The UCSF study team conducted a randomized, placebo-controlled, double-blinded crossover study of l8 children with hereditary hyperlipidemia. None of the participants were on lipid-lowering or other medications and none were smokers. Familial hypercholesterolemia (FH) was defined as both low-density lipoprotein (LDL) cholesterol above 130 mg/dl and a parent with the disorder. Familial combined hyperlipidemia (FCH) was diagnosed as either LDL cholesterol in excess of 130 mg/dl, a triglyceride count of greater than 150 md/dl, or both and a parent with any of these three phenotypes. 12 study participants carried the diagnosis of FCH; 6 of FH.
A nutritional education program was used for the six month study period. After six weeks of diet alone the participants were randomized to receive antioxidant vitamins C and E or placebo. This was followed by a six-week washout and a six week crossover phase. At baseline and at each six-week interval, three-day food records were obtained and lipoprotein profiles were measured. Serum was assayed for PON1 activity and DNA was isolated for PON1 genotyping.
PCR primers previously characterized for amplification of the PON1 gene polymorphism were synthesized and amplifications were performed. Plasma PON1 activity was determined by measuring the hydrolysis of paraoxon using an adaptation of spectrophotometric methods.