Perilipin polymorphism interacts with dietary carbohydrates to modulate anthropometric traits in hispanics of Caribbean origin

Abstract

Perilipin (PLIN) is the major protein surrounding lipid droplets in adipocytes and regulates adipocyte metabolism by modulating the interaction between lipases and triacylglycerol stores. Associations between PLIN gene polymorphisms and obesity risk have been described, but interactions with dietary macronutrients require further attention. We examined whether dietary macronutrients (e.g. carbohydrates and fats) modulated the associations of the common PLIN 11482G > A (rs894160) single nucleotide polymorphism with obesity. We studied a population-based sample of Caribbean-origin Hispanics (n = 920, aged 45-74 y) living in the Boston area. Obesity measures (waist and hip circumference, BMI) did not differ between GG subjects and carriers of the A allele (GA and AA). In multivariate linear regression models, we found a significant interaction between complex carbohydrate intake as a continuous variable and PLIN 11482 G > A genotype for waist circumference (P = 0.002). By dichotomizing complex carbohydrate intake, we found significantly different effects across PLIN 11482G > A genotypes. When complex carbohydrate intake was <144 g/d, waist circumference was larger in PLIN 11482G > A carriers (P = 0.024). Conversely, when complex carbohydrate intake was >/=144 g/d, waist and hip circumferences were less in PLIN 11482G > A carriers (P < 0.05). These interactions were not found for simple sugars or total carbohydrates. We identified a significant gene-diet interaction associated with obesity at the PLIN locus. In subjects with higher complex carbohydrate intake, the minor allele was protective against obesity, whereas in subjects with lower carbohydrate intake, the minor allele was associated with increased obesity. These interactions may be relevant to dietary management of obesity.

Figures

FIGURE 1

Waist circumference (A) by PLIN 11482G > A genotype and complex carbohydrate intake, adjusted for total energy intake using the residuals method. High complex carbohydrate ≥144 g/d. Low complex carbohydrate <144 g/d. Values are means + SE. Means were adjusted for age, sex, smoking, alcohol, physical activity, diabetes medications, saturated fat, dietary fiber, and simple sugars. P-values for trend were obtained through comparisons of means for genotype (GG, n = 480; GA, n = 353; AA, n = 71) according to complex carbohydrate intake. P for interaction was obtained for the interaction between genotype and complex carbohydrate intake. Means marked with different letters differ, P < 0.05. Predicted values of waist (B) by PLIN 11482G > A genotype (GG, n = 480; GA+AA, n = 424) plotted against complex carbohydrate intake (g/d, adjusted for total energy using residuals method) as a continuous variable. Predicted values for waist were calculated from the regression model after adjustment for age, sex, smoking, alcohol, physical activity, diabetes medications, saturated fat, and simple sugars. P-value for interaction indicates the significance of the interaction term for complex carbohydrate and PLIN genotype in the adjusted regression model. P-values for GG and GG+AA indicate the significance of the regression coefficients in the adjusted regression model.