Abstract

Several currently available antihyperglycemic drugs for diabetes mellitus have many weaknesses and adverse side effects, underscoring the need to find alternative therapies derived from medicinal plants, such as Castanopsis costata. Therefore, the objective of this study was to investigate antihyperglycemic and hypoglycemic effects of ethanol extract in C. costata (EECC) with in vitro and in vivo experimental models as well as identify the chemical compounds. The inhibitory activity of α-amylase and α-glucosidase by EECC was assessed using the DNSA and p-nitrophenyl-α-D-glucoside methods. The activity of lowering blood glucose level by EECC was examined in three test models in mice, namely normoglycemia, oral glucose tolerance test, and alloxan-induced hyperglycemia mice models, as well as histopathological studies of pancreatic tissue. The chemical compounds contained in EECC were identified using liquid chromatography tandem mass spectrometry. The results showed that EECC had inhibitory activity against α-amylase and α-glucosidase with respective IC50 values of 454.72 ± 0.86 and 575.08 ± 0.93 μg/ml. The administration of EECC caused a significant decrease in BGL in the three test models and a significant improvement from histopathological changes in pancreatic tissue. Meanwhile, chemical compound identification results showed that there were 14 compounds contained in EECC. This study showed that EECC has hypoglycemic and antihyperglycemic effects and was able to restore histopathological changes.

Key words: Castanopsis costata, hyperglycemic, in vitro, in vivo, histopathological.