Department of Nutrition and Health Science, Taipei Medical University, Taipei 11031, Taiwan.
Research Center of Geriatric Nutrition, College of Nutrition, Taipei Medical University, Taipei 11031, Taiwan.
Nutrients. 2023 Jun 19;15(12):2800. doi: 10.3390/nu15122800.
Postmenopausal obesity is a rising problem. Melatonin (Mel) is a hormone secreted by the pineal gland that regulates the circadian rhythms and improves obesity. In this experiment, ovariectomized (OVX) rats were used as a menopause model to explore the effects of Mel supplementation on lipid metabolism, body fat accumulation, and obesity. Nine-week-old female rats underwent an OVX surgery and were assigned to the following groups: control group (C), low-dose group (L, 10 mg/kg body weight (BW) Mel), medium-dose group (M, 20 mg/kg BW Mel), and high-dose group (H, 50 mg/kg BW Mel), administered by gavage for 8 weeks. The results showed that the OVX rats supplemented with low, medium, and high doses of Mel for 8 weeks exhibited reduced BW gain, perirenal fat mass, and gonads fat mass, and an increased serum irisin level. Low and high doses of Mel induced brite/beige adipocytes in the white adipose tissues. In addition, the messenger RNA levels of the fatty acid synthesis enzymes were significantly reduced after the high-dose Mel supplementation. Thus, Mel can reduce the hepatic fatty acid synthesis and promote the browning of white adipose tissues through irisin; thereby, improving obesity and body fat accumulation in OVX rats.
绝经后肥胖是一个日益严重的问题。褪黑素（Mel）是由松果体分泌的一种激素，可调节昼夜节律并改善肥胖。在这项实验中，使用去卵巢（OVX）大鼠作为绝经模型，以探讨褪黑素补充对脂代谢、体脂肪积累和肥胖的影响。9 周龄雌性大鼠接受 OVX 手术后被分为以下几组：对照组（C）、低剂量组（L，10mg/kg 体重（BW）Mel）、中剂量组（M，20mg/kg BW Mel）和高剂量组（H，50mg/kg BW Mel），通过灌胃给药 8 周。结果表明，补充低、中、高剂量 Mel 8 周的 OVX 大鼠体重增加减少，肾周脂肪质量和性腺脂肪质量减少，血清鸢尾素水平增加。低剂量和高剂量的 Mel 诱导白色脂肪组织中出现米色/beige 脂肪细胞。此外，高剂量 Mel 补充后脂肪酸合成酶的信使 RNA 水平显著降低。因此，Mel 可以通过鸢尾素减少肝脏脂肪酸合成并促进白色脂肪组织的褐色化，从而改善 OVX 大鼠的肥胖和体脂肪积累。
