Research

Racial difference in Acylation Stimulating Protein (ASP) correlates to triglyceride in non-obese and obese African American and Caucasian women

Thea Scantlebury-Manning¹ , Joseph Bower² , Katherine Cianflone³ and Hisham Barakat²

¹  Department of Biological and Chemical Sciences, Faculty of Pure and Applied Sciences, University of The West Indies, Cave Hill Campus, Bridgetown, St Michael, Barbados

²  Brady School of Medicine, East Carolina University, Greenville, North Carolina, USA

³  Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec, Canada

author email corresponding author email

Nutrition & Metabolism 2009, 6:18doi:10.1186/1743-7075-6-18

Published:	17 April 2009

Abstract

Background

Acylation Stimulating Protein (ASP) has been shown to influence adipose tissue triglyceride (TG) storage. The aim was to examine ethnic differences in ASP and leptin levels in relation to lipid profiles and postprandial changes amongst African American (AA) and Caucasian American (CA) women matched for BMI.

Methods

129 women were recruited in total (age 21 – 73 y): 24 non-obese (BMI < 30 kg/m²) CA, 27 obese (BMI ≥ 30 kg/m²) CA, 13 obese diabetic CA, 25 non-obese AA, 25 obese AA, and 15 obese diabetic AA. Cholesterol, HDL-C, LDL-C, apoB, glucose and insulin were measured at baseline. TG, non-esterified fatty acids, leptin, and ASP were measured at baseline and postprandially following a fat meal.

Results

ASP, leptin, insulin and TG were significantly increased in obese subjects within each race. However, AA women had significantly lower ASP and TG than CA women at all BMI. Obese and diabetic AA women had significantly lower apoB levels than CA women when compared to their respective counterparts. For AA women, fasting ASP was positively correlated with BMI, cholesterol, apoB, LDL-C and glucose. For CA women, fasting ASP was positively correlated with BMI, leptin, glucose and insulin. However, for any given BMI, ASP was significantly reduced in AA vs CA (p = 0.0004). Similarly, for any given leptin level or TG levels, ASP was significantly lower in AA women (p = 0.041 and p = 0.003, respectively).

Conclusion

CA women have higher baseline TG levels and an earlier TG peak that is accompanied with higher ASP levels suggesting increased ASP resistance, while AA women have lower baseline TG levels and a later TG peak at lower ASP levels suggesting increased ASP sensitivity. This may explain why AA women may have fewer metabolic complications, such as diabetes and CVD, when compared to their Caucasian counterparts at the same level of obesity.