Protective effects of silibinin against insulin amyloid fibril-induced toxicity in SH-SY5Y human neuroblastoma cells

Misfolding and deposition of various peptides and proteins is a key pathogenic feature of more than 20 amyloid-related diseases. Inhibition of protein aggregation is therefore viewed as a potential method to halt or slow the progression of neurodegenerative disorders. In this regard, numerous reports have demonstrated the effectiveness of some of the naturally occurring small molecules, and specially certain natural polyphenols, on prevention of protein aggregation and their associated cytotoxicity. In the present study, the effect of silibinin, as a major biologically active component extracting from the seeds of milk thistle plant named Silybum marianum, on the cytotoxic action of insulin fibrils was tested with human neuroblastoma SH-SY5Y cells. Insulin fibril-induced neuronal toxicity was verified by the MTT viability assay, intracellular ROS measurement, and morphological analysis. We found that the cell exposure to the co-incubated insulin amyloids with silibinin led to the increased cell viability and decreased ROS content dose-dependently, compared to cells exposed to insulin fibrils alone. Co-incubation with silibinin also attenuated the extent of morphological alterations induced by insulin fibrils. These results suggest that silibinin has protective effects against insulin fibrils induced cytotoxicity, which might be a potential therapeutic agent for treating or preventing neurodegenerative diseases.

کلیدواژه ها:

Insulin ، Amyloid fibril ، Silibinin ، SH-SY5Y cells ، Cytotoxicity