Background: Changes in the ratios of plasma lipids and apolipoproteins may be associated with diets and the C161T polymorphism in the gene of peroxisome proliferators activated receptor gamma (PPARgamma). As a result, this study was to investigate the effects of this polymorphism on changes of the ratios induced by a high-carbohydrate (high-CHO) diet.
Methods: After a washout diet of 54% carbohydrate for 7 days, 56 healthy young adults (22.89 +/- 1.80 years old) were given the high-CHO diet of 70% carbohydrate for 6 days. Height, weight, waist circumference (WC), glucose, triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), apolipoprotein (apo) AI, and apoB100 at baseline and before and after the high-CHO diet were measured. Body mass index (BMI), TG/HDL-C, log (TG/HDL-C), TC/HDL-C, LDL-C/HDL-C, and apoB100/apoAI were calculated. PPARgamma C161T was detected by a PCR-RFLP method. The relationship between the polymorphism and the ratios were analyzed.
Results: The female T carriers had higher BMI and WC than the female CC homozygotes at baseline and before and after the diet, higher glucose, TG/HDL-C and log (TG/HDL-C) before the diet. In males, when compared to the T carriers, the CC homozygotes had higher TG/HDL-C, log (TG/HDL-C) and apoB100/apoAI at baseline and before and after the diet, higher glucose at baseline, higher LDL-C/HDL-C and TC/HDL-C before and after the diet. Compared with those before the high-CHO diet, TC/HDL-C and LDL-C/HDL-C decreased after the diet regardless of gender and the genotypes. Decreased BMI and WC were observed in the male CC homozygotes but only decreased BMI in the female T carriers. Notably, decreased apoB100/apoAI was observed in the male T carriers, while elevated TG/HDL-C and log (TG/HDL-C) in the female CC homozygotes, and reduced glucose in the female T carriers.
Conclusions: The results suggest that the interplay of gender, the PPARgamma C161T polymorphism and the high-CHO diet can change not only the ratios of plasma lipids and apolipoproteins but also the association of the ratios with plasma glucose, WC, and BMI in healthy Chinese young adults. Once confirmed by larger sample size and multi-center trials, the findings will provide a new scientific basis for personalized dietary intervention for the subjects with different PPARgamma C161T genotypes to reduce risks of CAD, especially in a country with a quarter of the world's population.