The Antidiabetic Activities of Neocryptotanshinone: Screened by Molecular Docking and Related to the Modulation of PTP1B

The aim of this study was to provide a practical experimental basis for the development of Neocryptotanshinone (NCTS) as an effective hypoglycemic drug and a theoretical method for the rapid screening of natural compounds with hypoglycemic effects. Molecular docking was used to screen the most suitable ligand. Hematoxylin and eosin, immunohistochemical staining, enzyme-linked immunosorbent assay and Western Blotting approved the hypoglycemic effect of NCTS. According to the free energy of binding, among 180 active compounds from the Traditional Chinese Medicine Integrated Database, NCTS was finally chose for investigation its hypoglycemic effects. In db/db mice, NCTS significantly reduced body weight and plasma glucose, improved glucose tolerance and levels of fasting plasma glucose and glycated hemoglobin A1c, and decreased insulin resistance after six-week administration. NCTS restored the pathological state in the liver of db/db mice and significantly decreased protein tyrosine phosphatase 1B (PTP1B) expression in the liver and muscle of db/db mice, which is related to the regulatory effect of NCTS on insulin receptor substrate 1. In conclusion, we successfully explored the hypoglycemic effect of NCTS in db/db mice via regulating the expression of PTP1B.