Kochiae Fructus: Evaluation on the antioxidant properties and oral safety of its water decoction.

Kochiae Fructus (KF) was listed as 'top grade' medicinal material by the 'Shennong's Herbal Classic of Materia Medica' and has been used in traditional Chinese medicine to delay aging and treat inflammation, such as rubella, eczema, cutaneous pruritus, etc. Our research focused on the antioxidant capability of water decoction and fractions from KF based on 2,2-iphenyl-1-picrylhydrazyl (DPPH) free radical and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging assay, the ferric reducing antioxidant power assay, and inhibitory effects on DNA and protein oxidative damage. The results of total phenolics and flavonoids contents showed that ethyl acetate fraction (EAF) possessed the highest phenolics and flavonoids with values of 112.90 ± 9.58 mg gallic acid equivalents/g and 329.60 ± 20.93 mg rutin equivalents/g, respectively. At the same time, the results of antioxidant capacities showed that EAF possessed best antioxidant abilities. In addition, in this work, we evaluated the oral safety of the water decoction of KF (KFWD) via the 14-day acute and 28-day subacute toxicity tests. The results of in vivo toxicity assessment showed that KFWD did not cause significant changes in the general clinical symptoms, hematology and biochemical parameters, organ weights, or histopathological appearances in mice or rats. In summary, the reason why KF has the traditional effect on delaying aging may be related to the fact that its rich in flavonoids and phenolics. Simultaneously, no toxicity was detected after acute or subacute treatment of KFWD, providing valuable evidence for the traditional safe use of KF.

Antidiabetic potential of Catechu via assays for α-glucosidase, α-amylase, and glucose uptake in adipocytes.

ETHNOPHARMACOLOGICAL RELEVANCE: Catechu is the dry water extract of barked branches or stems from Senegalia catechu(L. F.)P. J. H. Hurter & Mabb, which is used as a hypoglycemic regulator in recent researches. Potential anti-hyperglycemic components and the putative mechanisms were evaluated in this investigation. AIM OF THE STUDY: Evaluated the hypoglycemic activity of Catechu via α-glucosidase, α-amylase inhibition assays, and glucose uptake in 3T3-L1 adipocytes. MATERIALS AND METHODS: The effects of Catechu on α-glucosidase, α-amylase inhibition assays and glucose uptake experiment were tested after the ethanol extract of Catechu (EE) was sequentially partitioned with petroleum ether (PEE), ethyl acetate (EAE), and n-butanol fractions (NBE). Next, HPLC-MS and traditional Chinese medicine (TCM) database were used to detect and analyze the primary active ingredients presented in hypoglycemic fraction. In addition, in silico molecular docking study was used to evaluate the candidates' inhibitory activity against α-glucosidase and α-amylase. RESULTS: The results of α-glucosidase and α-amylase inhibition assays indicated that all fractions, with the exception of PEE, presented significant inhibitory effects on α-glucosidase and α-amylase. The inhibitory effect of NBE on α-glucosidase was similar to the positive control (NBE IC50 = 0.3353 ± 0.1215 µg/mL; Acarbose IC50 = 0.1123 ± 0.0023 µg/mL). Furthermore, the inhibitory kinetics of α-glucosidase revealed that all fractions except for PEE belong to uncompetitive type. In silico molecular docking analysis showed that the main compositions of NBE ((-)-epicatechin, cyanidin, and delphinidin) possessed superior binding capacities with α-glucosidase (3WY1 AutoDock score: 4.82 kcal/mol; -5.59 kcal/mol; -5.63 kcal/mol) and α-amylase (4GQR AutoDock score: 4.80 kcal/mol; -5.89 kcal/mol; -4.26 kcal/mol), respectively. The results of glucose uptake experiment indicated that EE, PEE, EAE, and NBE without significant promotion effect on glucose uptake rate of 3T3-L1 adipocytes (P > 0.05). CONCLUSION: This study revealed that the hypoglycemic effect of Catechu might be related to the inhibitory effects of phenols on digestive enzymes (α-glucosidase and α-amylase), and the possible active phenols were (-)-epicatechin, cyanidin, delphinidin and their derivatives, which provided scientific evidences for Catechu's traditional use to treat T2DM.