MEDICINAL PLANTS SUPPORT THE AMYLIN-SUPPRESSED VIABILITY OF ISLET β-CELLS

The pro­liferation of β-cells is the main contributor to the mass cell maintenance in the pancreatic islets. In our earlier work the suppression of β-cell growth by aggregated peptide hormone of the pancreas, amylin, has been proved. The in-vitro protection of the cells from aggregated amylin-associated death by several plant extracts and their constituents has been shown. In the present work, the development of β-cells was suppressed preliminary by aggregated amylin. Then, the ethanol extracts of rose petals (Rosa damascena), melilot (Melilotus officinalis), leaves of grape (Vitis vinifera) and sorrel (Rumex Confertus) and the phenol glycoside fraction of rose petals were added to the cultivation medium, and the growth of cells suppressed by aggregate amylin was observed. The promotion of cells viability was registered with the trypan blue exclusion test and the DNA-comet analysis. In the other series of experiments, the reverse of pre-formed amylin aggregates in the presence of several plant preparations was registered using Thioflavin T fluorescence. The significant linear correlation (r = 0.75, p=0.02) between two propensities of plant: to inhibit amylin aggregation (observed in our previous work) and to dissociate the peptide aggregates was observed. Probably, both of these properties of plant preparations are conditioned by their specific interaction with amylin molecule and elucidate the perspective of studied plants in the protection of pancreatic islet β-cells against amylin-induced lost.