Abstract:
Cross-sectional studies have shown that obesity is associated with lower intestinal cholesterol absorption and higher endogenous cholesterol synthesis. These metabolic characteristics have also been observed in patients with type 2 diabetes, metabolic syndrome, steatosis or cholestasis. The number of intervention studies evaluating the effect of weight loss on these metabolic characteristics is, however, limited, while the role of the different fat compartments has not been studied into detail. In a randomized trial, abdominally obese men (N = 54) followed a 6-week very low caloric (VLCD) diet, followed by a 2 week weight-maintenance period. Non-cholesterol sterols were measured at baseline and after 8 weeks, and compared to levels in lean participants (N = 25). After weight loss, total cholesterol (TC)-standardized cholestanol levels increased by 0.18 µmol/mmol (p < 0.001), while those of campesterol and lathosterol decreased by 0.25 µmol/mmol (p < 0.05) and 0.39 µmol/mmol (p < 0.001), respectively. Moreover, after weight loss, TC-standardized lathosterol and cholestanol levels were comparable to those of lean men. Increases in TC-standardized cholestanol after weight loss were significantly associated with changes in waist circumference (p < 0.01), weight (p < 0.001), BMI (p < 0.001) and visceral fat (p < 0.01), but not with subcutaneous and intrahepatic lipids. In addition, cross-sectional analysis showed that visceral fat fully mediated the association between BMI and TC-standardized cholestanol levels. Intrahepatic lipid content was a partial mediator for the association between BMI and TC-standardized lathosterol levels. In conclusion, diet-induced weight loss decreased cholesterol synthesis and increased cholesterol absorption. The increase in TC-standardized cholestanol levels was not only related to weight loss, but also to a decrease in visceral fat volume. Whether these metabolic changes ameliorate other metabolic risk factors needs further study.
摘要:
横断面研究表明,肥胖与较低的肠道胆固醇吸收和较高的内源性胆固醇合成有关。这些代谢特征也在2型糖尿病患者中观察到,代谢综合征,脂肪变性或胆汁淤积。评估减肥对这些代谢特征的影响的干预研究的数量是,然而,limited,虽然不同脂肪隔室的作用尚未详细研究。在一项随机试验中,腹部肥胖男性(N=54)遵循6周的极低热量(VLCD)饮食,然后是2周的体重维持期。在基线和8周后测量非胆固醇甾醇,并与精益参与者的水平进行比较(N=25)。减肥后,总胆固醇(TC)标准化的胆固醇水平增加了0.18μmol/mmol(p<0.001),而菜油甾醇和十二甾醇的含量降低了0.25μmol/mmol(p<0.05)和0.39μmol/mmol(p<0.001),分别。此外,减肥后,TC标准化的座甾醇和胆固醇水平与瘦男性相当。体重减轻后TC标准化的胆固醇的增加与腰围的变化显着相关(p<0.01),体重(p<0.001),BMI(p<0.001)和内脏脂肪(p<0.01),但不含皮下和肝内脂质。此外,横断面分析显示,内脏脂肪完全介导了BMI与TC标准化胆固醇水平之间的关联.肝内脂质含量是BMI和TC标准化的油甾醇水平之间关联的部分介质。总之,饮食诱导的体重减轻降低了胆固醇的合成,增加了胆固醇的吸收。TC标准化的胆固醇水平的增加不仅与体重减轻有关,而且内脏脂肪量减少。这些代谢变化是否能改善其他代谢危险因素还需要进一步研究。