Screening active components from for pancreatic β-cells protection.

Context: 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 Focke and the underlying mechanisms.

Materials And Methods: Aqueous stem extract of was incubated with MIN6 β-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 was enriched and the cytotoxicity and anti-proliferation on β-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: β-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. The active components that act as hypoglycaemic agents in are procyanidins, which protected MIN6 cells against PA-induced apoptosis by activating PI3K/Akt/FoxO1 signalling. These results indicate that β-cell extraction, combined with UPLC/MS, is a valid method for screening antidiabetic components from herbal medicines.