Chemical composition and hypoglycaemic effect of polyphenol extracts from Litchi chinensis seeds

The hypoglycaemic effects of Litchi chinensis Sonn. seeds extract (LSE) on type 2 diabetic (T2D) rats and the active constituents from LSE were investigated. As a result, 21 compounds including 3,5-dihydroxybenzoic acid, 3,4-dihydroxybenzaldehyde, procyanidin D, cianidanol, cinnamtannin B1, procyanidin A1, scopoletin, rutin, phlorizin and epicatechin-epicatechin-catechin were identified by UPLC-Q/TOF-MS. The content of polyphenols reached 43.37 ± 2.34 g of cianidanol/100 g. After one-month treatment, LSE improved quality of life of streptozotocin (STZ)/high fat diet induced T2D rats and protected against pancreas, liver and kidney tissues damage through the improvement of glucose tolerance and insulin resistance. In addition, LSE influenced lipid metabolism and increased mRNA levels of Bax and NF-κB, thereby inhibiting apoptosis-induced hepatic damage and inflammation to protect the body against diabetic exacerbation. For the first time, this study delineated Litchi seeds' anti-diabetic prospect of treatment for type 2 diabetes.