Bioactivity and Chemical Constituents of Different Polar Parts from Blueberry Leaves / 中国药学杂志

OBJECTIVE: To study the bioactivity and chemical constituents of different polar parts from blueberry leaves. METHODS: Blueberry leaves were extracted by ethanol and then the extract was sequentially partitioned into five fractions. Silicagel and Sephadex LH-20 chromatographic methods were applied to isolate and purify compounds. Their structures were elucidated by physiochemical properties and spectral analysis.The DPPH• radical scavenging activity, α-glycosidase and pancreatic lipase inhibition activity of different polar parts and partial compounds were determined. RESULTS: The n-butyl alcohol fraction(BF) showed the highest DPPH• radical scavenging activity and α-glycosidase inhibition activity. The ethyl acetate fraction(EAF) showed the strongest pancreatic lipase inhibition activity. A total of five compounds were isolated from the EAF, and their structures were identified as β-sitosterol(1), quercetin-3-O-α-L-arabinofuranoside(2), quercetin(3), quercetin-3-O-β-D-glucopyranoside(4) and 1-O-caffeoylquinic acid(5). A total of two compounds were isolated from the BF, and their structures were identified as quercetin-3-O-α-L-arabinoside(6) and quercetin-3-O-β-D-glucuronide(7). The results showed that compounds 3 and 5 had very good DPPH• radical scavenging and pancreatic lipase inhibitory activity, and compounds 1 and 3 had good α-glucosidase inhibitory activity. CONCLUSION: The different polar parts and compounds of blueberry leaves show strong DPPH• radical scavenging activity, α-glycosidase and pancreatic lipase inhibition activity. Compounds 1, 2, 5 and 6 are isolated from blueberry leaves for the first time.

Virtual Screening ofα-glycosidase Inhibitors in Cortex mori and Folium mori / 中国药房

OBJECTIVE:To virtually screen potential α-glycosidase inhibitor ingredients from C. mori and F. mori,and to pro-vide reference for finding out new typeα-glycosidase inhibitor ingredient. METHODS:Surflex-Dock module of Sybyl-x 2.0 molecu-lar simulation software was used to perform the docking of small molecule compound,which was from the ingredients of C. mori and F. mori as ligand stated in literatures,with α-glycosidase. Total score of affinity scoring function was equal to 7 as the thresh-old value,to judge potential α-glycosidase inhibitor ingredient in C. mori and F. mori. RESULTS:After 70 small molecule com-pounds docked with α-glycosidase, 10 compounds showed binding activity (Total score≥7.00). Among them, moracin M-3′-O-β-D-glucopyranoside,5,7,2′-trihydroxyflavanone-4′-O-β-D-glucoside,mulberroside A,resveratrol-4,3′-di-O-β-D-gluco-pyranoside and 1,4-dideoxy-1,4-imino-(2-O-β-D-glucopyranosyl)-D-arabinitol had higher binding activity with α-glycosidase(Total score>8.00). CONCLUSIONS:Multi-constituents of C. mori and F. Mori show potential α-glycosidase inhibitory activity. The method is a kind of highly targeted,rapid and efficient approach to discover α-glycosidase inhibitor from traditional Chinese medi-cine.

Research progress on treatment of diabetes with Tibetan medicine Huidouba / 中草药

Diabetes is a metabolic disorder characterized by insulin resistance and progressive failure of β cell. It becomes a major disease and causes much attention because of high incidence, high disability, and high morbidity. Traditional Chinese medicine and ethical minority medicine have certain effects on diabetes, such as regulating lipid and losing weight, improving insulin resistance, and reducing hypoglycemia risk, and also have obvious advantage in therapy for vascular complication. Studies show that Tibetan Huidouba can improve metabolism of blood glucose, triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), activity of superoxide dismutase (SOD) and malondialdehyde (MDA) content in diabetic animal. The metabolism includes inhibiting α-glycosidase enzyme, activating peroxisome proliferators activated receptors (PPAR), and inhibiting nicotinamide adenine dinucleotide phosphate coenzyme II (NADPH) oxidase.

Study on in vitro hypoglycemic effect and mechanism of Polygonum capitatum / 中草药

Objective: To investigate the hypoglycemic targets of Polygonum capitatum. Methods: Human liver cancer HepG2 cells were adopted to detect the supernatant culture medium glucose content, and the effect on PPAR-α and GLUT4 gene expression was investigated by qRT-PCR after treatment of P. capitatum extracts (PCB). INS-1 cells similar to islet β cells, divided into drug protection group and repair group, were adopted to determine the cell proliferation activity by MTT; The intracellular SOD and MDA levels were measured by biochemical method; The Cyt C and Caspase-3 protein expression levels were detected by Western blotting. Adopting maltose as substrate of α-glycosidase enzyme inhibition model, the inhibitory efficiency of PCB on glycosidic enzyme was determined. Results: PCB group significantly promoted the absorption of HepG2 cells to supernatant glucose and increased the expression of PPAR-α and GLUT4 genes significantly. Aim at protection and repair of INS-1 cells, PCB group significantly increased cell vitality and SOD level, reduced MDA level compared with model group, and at the same time significantly reduced Cyt C and Caspase-3 protein expression levels. PCB had inhibitory activity to α-glycosidase enzymes, with IC50 of 11.53 mg/mL. Conclusion: PCB could significantly increase the PPAR-α and GLUT4 genes expression to promote the absorption of HepG2 cells to supernatant glucose by blocking the Cyt C-Caspase-3 pathways to reduce apoptosis of islet cells which were damaged by STZ and by raising SOD and declining MDA to improve INS-1 cell oxidative stress; What’s more it has inhibitory activity to α-glycosidase enzymes.

Evaluation of standardisation parameters, pharmacognostic study, preliminary phytochemical screening and in vitro antidiabetic activity of Coccinia indica fruits as per WHO guidelines.

Coccinia indica an annual creeper is available all over India and well known for its antidiabetic property. In the present investigation, aqueous extract, and ethanolic extract of the fruits were made using hot extraction procedure using soxhlet apparatus, decoction and maceration. The qualitative phyto-chemical screening procedure was performed on each extract. Phyto-chemical study reveals that carbohydrates, tannins, phenols, alkaloids, saponins was present in both the extracts. An attempt has been made to highlight this folk herbal medicine through present study which will assist in the identification of fresh as well as dried crude samples of fruits anatomically and physiochemically. TLC finger printing and fluorescence analysis of powdered fruits has been conducted and reported .The antidiabetic activity is conducted by enzyme inhibition (α-glycosidase) in invitro method on each extract and ethanolic extract showed significant inhibition.