Evaluation of Silibinin Effect on Insulin Like Growth Factor-1 (IGF-1) Expression and Cell Proliferation in Human Foreskin Fibroblast: An in Vitro Study

Fibroblasts are involved in production of growth factors which are effective on cells’ growth and differentiation. They are the most adaptable cells in connective tissue with significant capacity for differentiation to the other cell group. Insulin-like growth factor-1 (IGF-1) plays an important role in differentiation and growth of different cell lines. Silibinin is extracted from seeds of Silybum marianum, which it's effects in cancer cell lines, have been studied in limited studies. In this study we evaluated the silibinin effect on viability and IGF-1 gene expression in human foreskin fibroblast (HFF).

The cytotoxic effect of 10, 20, 40 & 60 µM solution of silibinin was evaluated on HFF cells using MTT assay, after 24 & 48 hours. Then, the expression of IGF-1 gene was evaluated by means of real time-PCR.

Silibinin had toxic effect on HFF cells in dose-dependent manner after 24 hours of incubation in comparison with control group but no significant difference observed after 48 hours. Besides, after 24 hours of incubation, silibinin with a concentration of 20-40-60 µM significantly increased the IGF-1 gene expression in fibroblast cells in comparison with control group.

Based on the results, silibinin significantly induces IGF-1 gene expression in dose dependent manner after 24 hours incubation with HFF cells. However, in cytotoxicity assay, concentration of 60 µM caused the highest rate of cell death after 24 hours. So, before introduction of this compound as a fibroblasts proliferation stimulant, more extensive studies are needed.