Department of Food Science and Nutrition, Jeju National University, Jeju 63243, Korea.
Interdisciplinary Graduate Program in Advanced Convergence Technology & Science, Jeju National University, Jeju 63243, Korea.
Int J Environ Res Public Health. 2021 Feb 2;18(3):1367. doi: 10.3390/ijerph18031367.
Seaweed is known to have various health-promoting effects. However, the mechanisms underlying seaweed's antidiabetic effects remain unclear. We investigated the potential antidiabetic effects of seaweed water extracts and further examined their mechanism(s) using C2C12 mouse skeletal muscle cells. Briefly, we screened the physiochemical properties of seven seaweed extracts by comparing the antioxidant and α-glucosidase inhibitory effects. Among them, three seaweed extracts, sporophyll (UPS), (CF), and (GV), were selected for further testing of their possible antidiabetic effects with underlying mechanisms using C2C12 myotubes. Consistent with the superior α-glucosidase inhibition of the three seaweed extracts, the extracts also enhanced glucose utilization in myotubes compared to the control. The upregulated glucose uptake by the seaweed extracts was reversed by an AMP-activated protein kinase (AMPK) inhibitor, compound C, in the UPS- and CF-treated groups. Furthermore, all three seaweed extracts significantly promoted the phosphorylation of AMPK which was completely blocked by pretreating with compound C. In addition, all three extracts reduced lipopolysaccharide-simulated TNF-α production in C2C12 cells. Our results demonstrated that all three seaweed extracts exhibited antidiabetic properties through not only the inhibition of glucose absorption but also the promotion of glucose utilization. Moreover, the regulation of inflammatory cytokine production by the extracts suggested their potential anti-inflammatory property which might play a critical role in protecting insulin sensitivity in a chronic inflammatory state. Taken together, UPS, CF, and GV are a promising source to modulate the glucose absorption and utilization in muscle cells partially via the AMPK pathway.
海藻被认为具有多种促进健康的作用。然而，海藻降血糖作用的机制尚不清楚。我们研究了海藻水提取物的潜在降血糖作用，并使用 C2C12 小鼠骨骼肌细胞进一步研究了其机制。简而言之，我们通过比较抗氧化和α-葡萄糖苷酶抑制作用来筛选七种海藻提取物的理化性质。其中，三种海藻提取物，孢子叶（UPS）、叶状体（CF）和配子体（GV），被选中用于使用 C2C12 肌管进一步测试其可能的降血糖作用及其潜在机制。与三种海藻提取物卓越的α-葡萄糖苷酶抑制作用一致，提取物还增强了肌管中的葡萄糖利用。与对照相比，海藻提取物通过 AMP 激活蛋白激酶（AMPK）抑制剂化合物 C 逆转了葡萄糖摄取的增加。此外，三种海藻提取物均显著促进了 AMPK 的磷酸化，而用化合物 C 预处理则完全阻断了磷酸化。此外，三种提取物均降低了脂多糖刺激的 C2C12 细胞中 TNF-α的产生。我们的结果表明，三种海藻提取物均通过抑制葡萄糖吸收和促进葡萄糖利用表现出降血糖特性。此外，提取物对炎性细胞因子产生的调节表明其具有潜在的抗炎特性，这可能在慢性炎症状态下保护胰岛素敏感性方面发挥关键作用。总之，UPS、CF 和 GV 是一种很有前途的调节肌肉细胞葡萄糖吸收和利用的来源，部分通过 AMPK 途径。
