Diabetes mellitus, linked with insulin resistance and hyperglycaemia, is a leading cause of mortality. Glucose uptake through glucose transporter type 4, especially in skeletal muscle, is crucial for maintaining euglycaemia and is a key pathway targeted by antidiabetic medication. Abrus precatorius is a medicinal plant with demonstrated antihyperglycaemic activity in animal models, but its mechanisms are unclear.

This study evaluated the effect of a 50% ethanolic (v/v) A. precatorius leaf extract on (1) insulin-stimulated glucose uptake and (2) related gene expression in differentiated C2C12 myotubes using rosiglitazone as a positive control, and (3) generated a comprehensive phytochemical profile of A. precatorius leaf extract using liquid chromatography-high resolution mass spectrometry to elucidate its antidiabetic compounds.

A. precatorius leaf extract significantly increased insulin-stimulated glucose uptake, and insulin receptor substrate 1 and Akt substrate of 160 kDa gene expression; however, it had no effect on glucose transporter type 4 gene expression. At 250 µg/mL A. precatorius leaf extract, the increase in glucose uptake was significantly higher than 1 µM rosiglitazone. Fifty-five phytochemicals (primarily polyphenols, triterpenoids, saponins, and alkaloids) were putatively identified, including 24 that have not previously been reported from A. precatorius leaves. Abrusin, precatorin I, glycyrrhizin, hemiphloin, isohemiphloin, hispidulin 4′-O-β-D-glucopyranoside, homoplantaginin, and cirsimaritin were putatively identified as known major compounds previously reported from A. precatorius leaf extract.

A. precatorius leaves contain antidiabetic phytochemicals and enhance insulin-stimulated glucose uptake in myotubes via the protein kinase B/phosphoinositide 3-kinase pathway by regulating insulin receptor substrate 1 and Akt substrate of 160 kDa gene expression. Therefore, A. precatorius leaves may improve skeletal muscle insulin sensitivity and hyperglycaemia. Additionally, it is a valuable source of bioactive phytochemicals with potential therapeutic use for diabetes.

糖尿病与胰岛素抵抗和高血糖有关，是导致死亡的主要原因。通过 4 型葡萄糖转运蛋白（尤其是骨骼肌）摄取葡萄糖对于维持血糖正常至关重要，也是抗糖尿病药物的关键途径。相思子是一种药用植物，在动物模型中显示出抗高血糖活性，但其机制尚不清楚。

本研究评估了 50% 乙醇 ( v/v ) A. precatorius叶提取物对 (1) 胰岛素刺激的葡萄糖摄取和 (2) 分化的 C2C12 肌管中相关基因表达的影响，使用罗格列酮作为阳性对照，以及 (3 ）使用液相色谱-高分辨率质谱法生成了A. precatorius叶提取物的全面植物化学特征，以阐明其抗糖尿病化合物。

A. precatorius叶提取物显着增加胰岛素刺激的葡萄糖摄取，以及胰岛素受体底物 1 和 Akt 底物 160 kDa 基因的表达；然而，它对葡萄糖转运蛋白 4 型基因表达没有影响。在 250 µg/mL 的A. precatorius叶提取物中，葡萄糖摄取的增加显着高于 1 µM 罗格列酮。推测鉴定出 55 种植物化学物质（主要是多酚、三萜类化合物、皂苷和生物碱），其中 24 种以前从未在A. precatorius叶子中报道过。相思子素、precatorin I、甘草皂苷、hemiphloin、isohemiphloin、hispidulin 4'- O - β -D-吡喃葡萄糖苷、homoplantaginin 和 cirsimaritin 被推定为先前从A. precatorius叶提取物中报道的已知主要化合物。

A. precatorius叶含有抗糖尿病植物化学物质，通过调节胰岛素受体底物 1 和 160 kDa 基因表达的 Akt 底物，通过蛋白激酶 B/磷酸肌醇 3-激酶途径增强肌管中胰岛素刺激的葡萄糖摄取。因此，A. precatorius叶可以改善骨骼肌胰岛素敏感性和高血糖。此外，它是生物活性植物化学物质的宝贵来源，具有潜在的糖尿病治疗用途。