Feng Dan, Zou Jun, Zhang Shanshan, Li Xuechun, Lu Minqi
Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Preventive Medicine, School of Public Health, Sun Yat-sen University , Guangzhou 510080, China.
Department of Cardiology, Affiliated NanHai Hospital of Southern Medical University , Foshan 528200, China.
J Agric Food Chem. 2017 Jan 18;65(2):276-280. doi: 10.1021/acs.jafc.6b04102. Epub 2017 Jan 3.
We previously demonstrated that curcumin reduces cholesterol absorption in Caco-2 cells through down-regulating Niemann-Pick C1-like 1 (NPC1L1) expression, but the in vivo effect of curcumin on intestinal cholesterol absorption remains unknown. The present study aimed to investigate the effects and mechanisms of curcumin consumption on cholesterol absorption in hamsters. Male hamsters were fed a high-fat diet supplemented with or without curcumin (0.05% w/w) for 12 weeks. Curcumin supplementation significantly decreased serum total cholesterol (TC) (from 6.86 ± 0.27 to 3.50 ± 0.24 mmol/L), triglyceride (TG) (from 5.07 ± 0.34 to 3.72 ± 0.40 mmol/L), and low-density lipoprotein cholesterol (from 2.58 ± 0.19 to 1.71 ± 0.15 mmol/L) levels as well as liver TC (from 11.6 ± 0.05 to 7.2 ± 0.03 mg/g) and TG (from 30.3 ± 0.22 to 25.2 ± 0.18 mg/g) levels (P < 0.05 for all). In contrast, curcumin treatment markedly enhanced fecal cholesterol output (P < 0.01). Moreover, curcumin supplementation down-regulated the mRNA and protein expressions of sterol regulatory element binding protein-2 (SREBP-2) and NPC1L1 in the small intestine (P < 0.05). Our current results indicate that curcumin inhibits cholesterol absorption in hamsters by suppressing SREBP-2 and subsequently down-regulating NPC1L1 expression, which may be responsible for the hypocholesterolemic effects of curcumin.
我们之前证明，姜黄素通过下调尼曼-匹克C1样1蛋白（NPC1L1）的表达来降低Caco-2细胞中的胆固醇吸收，但姜黄素对肠道胆固醇吸收的体内作用仍不清楚。本研究旨在探讨食用姜黄素对仓鼠胆固醇吸收的影响及其机制。雄性仓鼠被喂食含或不含姜黄素（0.05% w/w）的高脂饮食12周。补充姜黄素显著降低了血清总胆固醇（TC）（从6.86±0.27降至3.50±0.24 mmol/L）、甘油三酯（TG）（从5.07±0.34降至3.72±0.40 mmol/L）和低密度脂蛋白胆固醇（从2.58±0.19降至1.71±0.15 mmol/L）水平，以及肝脏TC（从11.6±0.05降至7.2±0.03 mg/g）和TG（从30.3±0.22降至25.2±0.18 mg/g）水平（所有P<0.05）。相反，姜黄素处理显著提高了粪便胆固醇排出量（P<0.01）。此外，补充姜黄素下调了小肠中固醇调节元件结合蛋白-2（SREBP-2）和NPC1L1的mRNA和蛋白表达（P<0.05）。我们目前的结果表明，姜黄素通过抑制SREBP-2并随后下调NPC1L1表达来抑制仓鼠的胆固醇吸收，这可能是姜黄素降胆固醇作用的原因。
