Taiwanese green propolis ethanol extract delays the progression of type 2 diabetes mellitus in rats treated with streptozotocin/high-fat diet

Taiwanese green propolis ethanol extract (TGPE) is produced only in Taiwan and has a different composition from other types of propolis. TGPE is known for its anti-inflammation, anti-oxidation, and anti-microbial properties, but the effects and mechanisms of TGPE in the modulation of diabetes are unclear. In this study, we investigated the effects of TGPE on type 2 diabetes mellitus (T2DM) in a streptozotocin/high-fat-diet (STZ/HFD)-induced T2DM rat model. The results revealed that TGPE delayed the development and progression of T2DM and reduced the severity of β-cell failure. TGPE also attenuated inflammation and reactive oxygen species ROS in the rats. Moreover, there were higher levels of oxidant cytokines, leptin, and adiponectin in the serum of the TGPE-treated group. Unlike Brazilian propolis, TGPE promoted hepatic genes PPAR-α and CYP7A1, which were related to lipid catabolism and removal. TGPE may thus delay the progression of T2DM through anti-inflammation effects, anti-oxidation effects, and balancing lipid metabolism. It is suggested that TGPE can be a potential alternative medicine for T2DM.