Després J P, Couillard C, Gagnon J, Bergeron J, Leon A S, Rao D C, Skinner J S, Wilmore J H, Bouchard C
Lipid Research Center, CHUQ Research Center, CHUL Pavilion, Sainte-Foy, Québec, Canada.
Arterioscler Thromb Vasc Biol. 2000 Aug;20(8):1932-8. doi: 10.1161/01.atv.20.8.1932.
Abdominal obesity is associated with numerous metabolic alterations, such as hypertriglyceridemia and low levels of high density lipoprotein (HDL) cholesterol. However, compared with abdominally obese white individuals, abdominally obese black individuals have been characterized by higher plasma HDL cholesterol levels, suggesting that the impact of abdominal fat accumulation on the lipoprotein-lipid profile may differ among ethnic groups. Therefore, we have compared the associations between body fatness, visceral adipose tissue (AT) accumulation, and metabolic risk variables in a sample of 247 white men and 240 white women versus a sample of 93 black men and 143 black women. Although no difference in mean total body fatness was found between the 2 race groups, white men had higher levels of visceral AT than did black men (P<0.001). Despite the fact that black women had a greater body fat content than did white women, black women had levels of visceral AT that were similar to those of white women, suggesting a lower susceptibility to visceral obesity in black women. This lower accumulation of visceral AT in blacks was accompanied by significantly reduced apolipoprotein B concentrations and ratios of total cholesterol to HDL cholesterol as well as higher plasma HDL cholesterol levels (P<0.05) compared with those values in whites. Irrespective of sex, higher postheparin plasma hepatic lipase (HL) and lower lipoprotein lipase (LPL) activities were found in whites, resulting in an HL/LPL ratio that was twice as high in whites as in blacks (P<0.005). Although differences in lipoprotein-lipid levels were noted between whites and blacks, results from multiple regression analyses revealed that after control for morphometric and metabolic variables of the study (body fat mass, visceral AT, LPL, HL, and age), ethnicity had, per se, only a minor contribution to the variance in plasma lipoprotein levels. Thus, our results suggest that the higher plasma HDL cholesterol levels and the generally more cardioprotective plasma lipoprotein profile found in abdominally obese black versus white individuals are explained, at least to a certain extent, by a lower visceral AT deposition and a higher plasma LPL activity in black individuals.
腹部肥胖与众多代谢改变相关,如高甘油三酯血症和低水平的高密度脂蛋白(HDL)胆固醇。然而,与腹部肥胖的白人个体相比,腹部肥胖的黑人个体的血浆HDL胆固醇水平较高,这表明腹部脂肪堆积对脂蛋白-脂质谱的影响可能因种族而异。因此,我们比较了247名白人男性和240名白人女性样本与93名黑人男性和143名黑人女性样本中身体脂肪、内脏脂肪组织(AT)堆积与代谢风险变量之间的关联。尽管在两个种族组之间未发现平均总体脂存在差异,但白人男性的内脏AT水平高于黑人男性(P<0.001)。尽管黑人女性的体脂含量高于白人女性,但黑人女性的内脏AT水平与白人女性相似,这表明黑人女性对内脏肥胖的易感性较低。与白人相比,黑人内脏AT的这种较低堆积伴随着载脂蛋白B浓度、总胆固醇与HDL胆固醇比值的显著降低以及血浆HDL胆固醇水平的升高(P<0.05)。无论性别如何,白人的肝素后血浆肝脂酶(HL)活性较高,脂蛋白脂酶(LPL)活性较低导致白人的HL/LPL比值是黑人的两倍(P<0.005)。尽管白人和黑人之间的脂蛋白-脂质水平存在差异,但多元回归分析结果显示,在控制了研究的形态学和代谢变量(身体脂肪量、内脏AT、LPL、HL和年龄)后,种族本身对血浆脂蛋白水平差异的贡献很小。因此,我们的结果表明,腹部肥胖的黑人个体与白人个体相比,较高的血浆HDL胆固醇水平和总体上更具心脏保护作用的血浆脂蛋白谱至少在一定程度上可以通过黑人个体较低的内脏AT沉积和较高的血浆LPL活性来解释。