LC-Q-TOF-MS Characterization of Polyphenols from White Bayberry Fruit and Its Antidiabetic Effect in KK‑Ay Mice

• Published in: ACS omega 2020-07, Vol.5 (28), p.17839-17849
• Main Authors: Liu, Yilong, Zhang, Xianan, Zhan, Liuhuan, Xu, Chang, Sun, Linxiao, Jiang, Huamin, Sun, Chongde, Li, Xian
• Format: Article
• Language: English
• ISSN: 2470-1343; 2470-1343
• DOI: 10.1021/acsomega.0c02759

The present study is to investigate the polyphenolic composition and in vivo antidiabetic effect of white-fleshed Chinese bayberry cultivar “Shui Jing”. By liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS), 38 polyphenols were identified in the Shui Jing fruit extract (SJE), where proanthocyanidins (PAs), including epigallocatechin gallate (EGCG), as well as flavonols, including myricitrin and quercetrin, were the predominant ingredients. After a 5-week experiment, the SJE (200 mg/kg bodyweight) significantly reduced fasting blood glucose, elevated glucose tolerance, and insulin sensitivity in diabetic KK-Ay mice. It markedly attenuated bodyweight gain and decreased glycolipid metabolism-related markers including insulin, leptin, glucagon, triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c) and alanine aminotransferase (ALT) levels in mice. Liver weight and hepatic lipid accumulation were also significantly reduced by the SJE. Gene expressions of insulin 1 (INS1) and glycogen synthase kinase 3 β (GSK3b) were markedly inhibited while the hepatic phosphorylation of AMPKα was significantly increased in the liver of SJE-treated mice, indicating that the SJE may exert an antidiabetic effect through an AMPK-dependent pathway. In conclusion, white bayberry rich in PAs and flavonols may have great potential in the regulation of diabetes mellitus.