Oriental Medicine R&D Center, Dongguk University, Gyeongju, Republic of Korea.
Pharm Biol. 2013 Aug;51(8):961-7. doi: 10.3109/13880209.2013.772211. Epub 2013 Apr 29.
Obesity is associated with a number of diseases with metabolic abnormalities such as type 2 diabetes (T2D). Medicinal plants have been widely used for the treatment of obesity and related complications.
In this study, we investigated the antidiabetic properties of the extract of twigs of Cinnamomum cassia Blume (Lauraceae) (Cinnamomi Ramulus; CR) in 3T3-L1 murine preadipocytes.
3T3-L1 cells were differentiated into adipocytes for 3 d in insulin-conditioned medium and then treated with CR extract at concentrations of 100 and 500 μg/mL for 6 d. Adipocyte differentiation was measured by Oil Red O staining, and the expression of master transcription factors, peroxisome proliferator-activated receptor-gamma (PPARγ), CCAAT/enhancer binding protein-alpha (C/EBPα), and sterol regulatory element binding protein-1c (SREBP-1c), and lipid metabolism factors were investigated by reverse transcription-polymerase chain reaction (RT-PCR). The activation of the AMP-activated protein kinase (AMPK)/insulin signaling pathway was assessed by western blot analysis.
CR extract significantly reduced lipid accumulation and down-regulated the expression of PPARγ, C/EBPα, and SREBP-1c in 3T3-L1 adipocytes. CR extract also suppressed the expression of fatty acid synthase (FAS), acyl-CoA synthase, and perilipin. Moreover, CR extract markedly up-regulated the phosphorylation of AMPK and acetyl-CoA carboxylase (ACC). In addition, CR extract effectively increased the expression levels of glucose transporter-4 (GLUT-4), phosphatidylinositol 3-kinase (PI3K), and insulin receptor substrate-1 (IRS-1) in 3T3-L1 adipocytes.
These results suggest that CR extract may have therapeutic potential as a natural agent for the improvement of T2D via regulation of the insulin-dependent signaling pathway.
肥胖与多种代谢异常疾病相关，如 2 型糖尿病（T2D）。药用植物已被广泛用于治疗肥胖症及其相关并发症。
本研究旨在探讨肉桂树枝（Cinnamomum cassia Blume）（樟科）提取物（肉桂树枝提取物；CR）在 3T3-L1 鼠前脂肪细胞中的抗糖尿病特性。
3T3-L1 细胞在胰岛素条件培养基中分化为脂肪细胞 3 天，然后用 100 和 500μg/ml 的 CR 提取物处理 6 天。用油红 O 染色法测量脂肪细胞分化，用逆转录-聚合酶链反应（RT-PCR）法检测主转录因子过氧化物酶体增殖物激活受体-γ（PPARγ）、CCAAT/增强子结合蛋白-α（C/EBPα）和固醇调节元件结合蛋白-1c（SREBP-1c）以及脂质代谢因子的表达。通过 Western blot 分析评估 AMP 激活的蛋白激酶（AMPK）/胰岛素信号通路的激活情况。
CR 提取物显著减少了 3T3-L1 脂肪细胞中的脂质积累，并下调了 PPARγ、C/EBPα 和 SREBP-1c 的表达。CR 提取物还抑制了脂肪酸合酶（FAS）、酰基辅酶 A 合成酶和脂滴包被蛋白的表达。此外，CR 提取物显著上调了 AMPK 和乙酰辅酶 A 羧化酶（ACC）的磷酸化水平。此外，CR 提取物还能有效增加 3T3-L1 脂肪细胞中葡萄糖转运蛋白-4（GLUT-4）、磷脂酰肌醇 3-激酶（PI3K）和胰岛素受体底物-1（IRS-1）的表达水平。
这些结果表明，CR 提取物可能通过调节胰岛素依赖的信号通路，作为一种天然药物具有治疗 2 型糖尿病的潜力。
