Screening active components from Rubus amabilis for pancreatic ß-cells protection.

CONTEXT: Rubus species (Rosaceae) have been used in folk medicine to treat diabetes due to their hypoglycaemic activity. OBJECTIVE: To screen the active components that act as hypoglycaemic agents in Rubus amabilis Focke and the underlying mechanisms. MATERIALS AND METHODS: Aqueous stem extract of R. amabilis was incubated with MIN6 ß-cells, PBS was used as the blank control. Then the cells were washed, cell membrane-bound components were dissociated and identified by UPLC/MS. Total procyanidins (PCs) in R. amabilis was enriched and the cytotoxicity and anti-proliferation on ß-cell were evaluated by MTT assay. PCs at 25, 50, and 75 µg/mL was applied for 24 h to determine its effects on palmitate (PA)-induced apoptosis and GSIS. Western blotting was employed to detect the protein expression of PI3K/Akt/FoxO1 signalling. The antioxidant indices were also measured. RESULTS: ß-Cell membrane-bound components were identified as three procyanidin B dimers and a C trimer. PCs showed no significant cytotoxicity up to a concentrations of 100 µg/mL. PCs treatment reversed the elevated apoptosis rate and impaired GSIS induced by PA. PCs markedly decreased the intracellular ROS and MDA production and increased the SOD activity. Moreover, PCs promoted the phosphorylation of Akt and FoxO1, and regulated Pdx-1 and Bax expression in MIN6 cells. Discussion and conclusion: The active components that act as hypoglycaemic agents in R. amabilis are procyanidins, which protected MIN6 cells against PA-induced apoptosis by activating PI3K/Akt/FoxO1 signalling. These results indicate that ß-cell extraction, combined with UPLC/MS, is a valid method for screening antidiabetic components from herbal medicines.

The Treatment of Cholecystitis and Cholelithiasis by Tibetan Medicine.

Cholecystitis and cholelithiasis is one of the factors threatening human health. It is very important to find drugs for the treatment of cholecystitis and cholelithiasis. Tibetan medicine is one of the traditional medical systems in China. It has rich experience in treating various diseases. This paper summarizes the treatment of cholecystitis and cholelithiasis through literature review of Tibetan medicine monographs, drug standards, Tibetan medicine, and prescriptions. In the Tibetan medicine system, 170 kinds of Tibetan medicine and 38 kinds of Tibetan prescriptions were found to treat cholecystitis and cholelithiasis. Among them, there are 35 modern researches related to the treatment of cholecystitis and cholelithiasis. Their names, families, medicinal parts, chemical constituents, and pharmacological activities are introduced in detail. These Tibetan medicines and prescriptions may be a precious gift of ancient Tibetan medicine to the world, and may also become potential drug candidates for the treatment of cholecystitis and cholelithiasis. Modern phytochemistry, pharmacology, metabonomics, and/or clinical trials can be used to confirm its medicinal value in the treatment of cholecystitis and cholelithiasis, identify active compounds, clarify its potential mechanism of action, and clarify its toxicity and side effects. This article provides a new idea and source for the treatment of cholecystitis and cholelithiasis.

Comparison of compounds of three Rubus species and their antioxidant activity.

Rubus amabilis, Rubus niveus Thunb., and Rubus sachalinensis are three Rubus species that are alternatively found in Manubzhithang, a Tibetan medicine, in different areas of China. The current study analyzed HPLC/UV chromatograms and it compared compounds of these three Rubus species in contrast to reference substances such as 2,6-dimethoxy-4-hydroxyphenol-1-O-ß-D-glucopyranoside, procyanidin B4, and isovitexin-7-O-glucoside. The three Rubus species produced similar peaks in chromatograms. The antioxidant activity of the three Rubus species was determined using an assay for DPPH free radical scavenging activity. Results indicated that the three Rubus species extracts had almost the same level of free radical scavenging activity. Thus, findings indicated the rationality of substituting these species for one another as an ingredient in Manubzhithang.