College of Life Science, Zhejiang Chinese Medical University, Hangzhou, 310053, China; School of Biomedical Science and Engineering, South China University of Technology, 510641, Guangzhou, China.
College of Life Science, Zhejiang Chinese Medical University, Hangzhou, 310053, China.
Phytomedicine. 2021 Feb;82:153447. doi: 10.1016/j.phymed.2020.153447. Epub 2020 Dec 25.
Carya cathayensisis a commercially cultivated plant in the Zhejiang Province, China. Its nuts exhibit properties of tonifying kidneys and relieving asthma. There have been a few pharmacological studies addressing the function of the leaves of this plant. Our previous studies on C. cathayensis leaf extract (CCE) showed a significant inhibitory effect on weight gain in mice fed a high-fat diet, particularly in female mice.
HYPOTHESIS/PURPOSE: To investigate the biological and molecular mechanisms underlying the regulation of ectopic adipose tissue deposition by CCE in ovariectomized rats fed a high-fat diet.
Female Sprague-Dawley rats were ovariectomized and treated with CCE (50, 100, and 200 mg/kg body weight, oral) or estradiol (1 mg/kg body weight, oral) for 8 weeks.
CCE was subjected to high-performance liquid chromatography to quantify major components. Body weight gain, abdominal fat coefficient, and aortic arch fat coefficient were determined; serum was collected for biochemical analysis; tissues were collected for histopathological examination, quantitative polymerase chain reaction (Q-PCR), and western blotting.
The total flavonoid content was determined to be 57.30% in the CCE and comprised chrysin, cardamomin, pinostrobin chalcone, and pinocembrin. Compared with the model group (OVX), CCE treatment reduced body weight gain, abdominal and aortic arch fat coefficients, serum and hepatic lipid profiles, including total cholesterol (TC), total triglycerides (TG), and free fatty acids (FFA) levels; decreased lipid droplets in liver cells; decreased fat accumulation in the aortic arch blood vessel wall and increased its smoothness; decreased the diameter of abdominal fat cells; and reduced serum leptin and adiponectin levels significantly. Serum adiponectin levels significantly correlated with serum TG and hepatic TC levels. Leptin levels positively correlated with serum TG levels and negatively correlated with hepatic TG. Leptin mRNA, peroxisome proliferator-activated receptor (PPARγ) mRNA, and protein expression levels in abdominal adipose tissue were significantly down-regulated. Adiponectin mRNA levels were slightly reduced but not significantly.
CCE attenuated ectopic fat deposition induced by deficient estrogen and a high-fat diet in rats; this may be associated with activated leptin sensitivity, improved leptin resistance, and regulated adiponectin levels. CCE may improve adipose function to regulate adipocyte differentiation by down-regulating PPARγ. Overall, these results suggest that CCE is a potential phytoestrogen.
山核桃是中国浙江省的一种商业种植植物，其坚果具有补肾平喘的功效。已有一些药理学研究关注该植物的叶子的功能。我们之前的研究表明，山核桃叶提取物（CCE）对高脂饮食喂养的肥胖小鼠，特别是雌性小鼠的体重增加具有显著的抑制作用。
假说/目的：研究 CCE 对高脂饮食喂养去卵巢大鼠异位脂肪组织沉积的调控的生物学和分子机制。
雌性 Sprague-Dawley 大鼠行卵巢切除术，并给予 CCE（50、100 和 200mg/kg 体重，口服）或雌二醇（1mg/kg 体重，口服）治疗 8 周。
采用高效液相色谱法测定 CCE 中的主要成分含量。测定体重增加、腹部脂肪系数和主动脉弓脂肪系数；收集血清进行生化分析；收集组织进行组织病理学检查、定量聚合酶链反应（Q-PCR）和蛋白质印迹分析。
CCE 中的总黄酮含量为 57.30%，包括白杨素、小豆蔻明、松脂素查耳酮和乔松素。与模型组（OVX）相比，CCE 治疗可降低体重增加、腹部和主动脉弓脂肪系数、血清和肝脂质谱，包括总胆固醇（TC）、总三酰甘油（TG）和游离脂肪酸（FFA）水平；减少肝细胞中的脂滴；减少主动脉弓血管壁的脂肪堆积并增加其平滑度；减少腹部脂肪细胞的直径；并显著降低血清瘦素和脂联素水平。血清脂联素水平与血清 TG 和肝 TC 水平显著相关。瘦素水平与血清 TG 水平呈正相关，与肝 TG 水平呈负相关。腹部脂肪组织中瘦素 mRNA、过氧化物酶体增殖物激活受体（PPARγ）mRNA 和蛋白表达水平显著下调。脂联素 mRNA 水平略有降低但不显著。
CCE 可减轻去卵巢和高脂饮食诱导的大鼠异位脂肪沉积；这可能与瘦素敏感性的激活、瘦素抵抗的改善以及脂联素水平的调节有关。CCE 可能通过下调 PPARγ 来改善脂肪功能，从而调节脂肪细胞分化。总的来说，这些结果表明 CCE 是一种潜在的植物雌激素。
