Anti-Diabetic Effect of a Shihunine-Rich Extract of Dendrobium loddigesii on 3T3-L1 Cells and db/db Mice by Up-Regulating AMPK-GLUT4-PPARα
Anti-Diabetic Effect of a Shihunine-Rich Extract of Dendrobium loddigesii on 3T3-L1 Cells and db/db Mice by Up-Regulating AMPK-GLUT4-PPARα
复制标题
富含紫苏碱的石斛提取物通过上调 AMPK-GLUT4-PPAR α 对 3T3-L1 细胞和 db/db 小鼠的抗糖尿病作用
DOI：
10.3390/molecules24142673
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发表时间：
2019-07-02
期刊：
影响因子：
4.6
通讯作者：
Wang, Jun
中科院分区：
文献类型：
--
作者：
Li, Xue-Wen;Huang, Meixiang;Wang, Jun
中草药石斛（Dendrobium loddigesii）的茎部常被用于治疗糖尿病，其极性提取物中含有丰富的水溶性兰科生物碱石胡碱，但对其抗糖尿病作用及其机制知之甚少。本研究以3T3-L1细胞和db/db小鼠为实验对象，研究了富shihunin提取物（DLS）的抗糖尿病作用。主要通过Western blot分析和免疫组织化学染色来探索潜在的机制。3T3-L1细胞实验表明，DLS可以减少细胞内油滴和甘油三酯的积聚（p < 0.001），促进3T3-L1细胞对2-[N-（7-硝基苯-2-氧-1,3-二唑-4-基）氨基]-2脱氧葡萄糖（2- nbdg）的摄取（p < 0.001）。动物实验证实，DLS治疗8周后，小鼠体重、空腹血糖、血脂水平明显降低，口服糖耐量试验和血清胰岛素水平较未治疗糖尿病组明显改善。进一步的组织形态学观察表明，胰岛细胞数量明显增加，脂肪细胞大小的增加明显受到抑制。胰腺组织免疫组化检测显示，DLS抑制了cleaved半胱氨酸天冬氨酸特异性蛋白酶3 （cleaved caspase-3）的表达。Western blot实验显示，DLS对单磷酸腺苷（AMP）活化的蛋白激酶磷酸化（p-AMPK）具有拮抗作用，提高肝脏和脂肪组织中过氧化物酶体增殖体活化受体α (PPAR α)和葡萄糖转运蛋白4 （GLUT4）的表达水平。这些数据表明，石胡碱丰富的石胡碱提取物是石胡碱的抗糖尿病部位。在我们的实验条件下，50mg /kg剂量的DLS具有良好的抗糖尿病效果。
The stems of Dendrobium loddigesii, a Chinese herb, are often used to treat diabetes and its polar extract is rich in shihunine, a water-soluble Orchidaceae alkaloid, but little is known about the anti-diabetes effects and mechanism of shihunine. This study investigated the anti-diabetic effect of a shihunine-rich extract of D. loddigesii (DLS) based on 3T3-L1 cells and db/db mice. The underlying mechanisms were primarily explored using Western blot analysis and immunohistochemical staining. The 3T3-L1 cell experiments showed that DLS can reduce the intracellular accumulation of oil droplets as well as triglycerides (p < 0.001) and promote the 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2deoxyglucose (2-NBDG) uptake of 3T3-L1 cells (p < 0.001). The animal experiments confirmed that after 8 weeks of DLS treatment, the body weight, fasting blood sugar, and serum lipid levels of mice were significantly lowered, and the oral glucose tolerance test and serum insulin level were significantly improved compared to the no-treatment diabetes mellitus group. Further histomorphology observation led to the conclusion that the quantities of islet cells were significantly increased and the increase in adipose cell size was significantly suppressed. The immunohistochemical test of pancreatic tissue revealed that DLS inhibited the expression of cleaved cysteine aspartic acid-specific protease 3 (cleaved caspase-3). Western blot experiments showed that DLS had agonistic effects on adenosine monophosphate (AMP)-activated protein kinase phosphorylation (p-AMPK) and increased the expression levels of peroxisome proliferator-activated receptor alpha (PPAR alpha) and glucose transporter 4 (GLUT4) in liver or adipose tissues. These data suggest that the shihunine-rich extract of D. loddigesii is an anti-diabetic fraction of D. loddigesii. Under our experimental condition, DLS at a dose of 50 mg/kg has good anti-diabetic efficacy.