Alcohol extract of morinda officinalis improves lipid metabolism and bone metabolism in ovariectomized obese rats / 中国组织工程研究

ABSTRACT

BACKGROUND: Previous studies have showed that the alcohol extract of Morinda officinalis can effectively improve the bone quality and body mass of obese rats after ovariectomy. However, the exact mechanism is unclear. In this study, leptin and leptin receptor were used as the breakthrough point to investigate the effect of alcohol extract of Morinda officinalis on lipid metabolism and bone metabolism in ovariectomized obese rats. OBJECTIVE: To investigate the effects of alcohol extract of Morinda officinalis lipid metabolism and bone metabolism in ovariectomized obese rats. METHODS: A total of 160 SPF female Sprague-Dawley rats were randomly divided into an osteoporosis group (n=120) and a sham operation group (n=40). A postmenopausal osteoporosis model was made in the osteoporosis group by removing both ovaries. After modeling, rats in the osteoporosis group were randomly subdivided into a normal diet group, a high-fat diet group and a high-fat diet + Morinda officinalis alcohol extract group, with 40 rats in each group. The sham operation group and the normal diet group were fed with ordinary diet, while the high-fat diet group and the high-fat diet + Morinda officinalis alcohol extract group were fed with high-fat diet. The high-fat diet + Morinda officinalis alcohol extract group was gavaged with 20 g/kg Morinda officinalis alcohol extract once a day, and the remaining three groups were gavaged with 2 mL of normal saline. The study protocol was approved by the Animal Ethic Committee of Fuzhou Second Hospital of Xiamen University in September 2018 with an approval No. 20180019. RESULTS AND CONCLUSION: Compared with the sham operation group, serum leptin, leptin receptor, osteoprotegerin and high-density lipoprotein cholesterol levels were significantly lower in ovariectomized rats (P < 0.05), whereas osteocalcin, RANKL, tartrate-resistant acid phosphatase 5b, cholesterol, triacylglycerol, and low-density lipoprotein cholesterol levels were significantly higher in ovariectomized rats (P < 0.05). Compared with the high-fat diet group, serum leptin, leptin receptor, osteoprotegerin and high-density lipoprotein cholesterol levels were significantly increased in the high-fat diet + Morinda officinalis alcohol extract group (P < 0.05), whereas osteocalcin, RANKL, tartrate-resistant acid phosphatase 5b, cholesterol, triacylglycerol, and low-density lipoprotein cholesterol levels were decreased to different extents in the high-fat diet + Morinda officinalis alcohol extract group (P < 0.05). To conclusion, the alcohol extract of Morindus officinalis can up-regulate the leptin and leptin receptor expression in serum of ovariectomized obese rats, so as to improve the abnormal bone metabolism and lipid metabolism in ovariectomized obese rats.