Yang Kaiyuan, Chan Catherine B
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada.
Nutr Rev. 2017 Aug 1;75(8):642-657. doi: 10.1093/nutrit/nux028.
Proanthocyanidins are a major group of flavonoids in the human diet, known for their strong antioxidant properties. Emerging evidence from clinical studies indicates a role of proanthocyanidins in modulating glucose homeostasis, and higher proanthocyanidin intake has been associated with reduced risk of diabetes. On the other hand, recent studies report limited bioavailability of proanthocyanidins. At relatively low concentrations in the systemic circulation, proanthocyanidins may act as cell-signaling molecules to modulate glucose homeostasis. For example, they affect hepatic glucose production via adenosine monophosphate-activated protein kinase and/or insulin-signaling pathways. There is also evidence for a direct role of proanthocyanidins in modulating several pancreatic β-cell functions: prevention of oxidative stress, enhancement of insulin secretion, and promotion of β-cell survival. Therefore, greater understanding of the potentially beneficial effects of proanthocyanidins on cell-signaling pathways implicated in glucose homeostasis is needed. In addition, further investigation to address the in vivo metabolism of proanthocyanidins and the comparative effectiveness of proanthocyanidin-derived metabolites is warranted. The dosage and the experimental model should be given special attention when results from mechanistic studies using proanthocyanidins are interpreted.
原花青素是人类饮食中主要的一类黄酮类化合物，以其强大的抗氧化特性而闻名。临床研究的新证据表明原花青素在调节葡萄糖稳态方面发挥作用，摄入较高剂量的原花青素与降低糖尿病风险相关。另一方面，最近的研究报告称原花青素的生物利用度有限。在体循环中浓度相对较低时，原花青素可能作为细胞信号分子来调节葡萄糖稳态。例如，它们通过腺苷单磷酸激活的蛋白激酶和/或胰岛素信号通路影响肝脏葡萄糖生成。也有证据表明原花青素在调节几种胰腺β细胞功能方面具有直接作用：预防氧化应激、增强胰岛素分泌以及促进β细胞存活。因此，需要更深入地了解原花青素对参与葡萄糖稳态的细胞信号通路的潜在有益作用。此外，有必要进一步研究原花青素的体内代谢以及原花青素衍生代谢物的相对有效性。在解释使用原花青素的机制研究结果时，应特别关注剂量和实验模型。
