Abstract

Osteoarthritis (OA) is known to be the most prevalent form of joint disease. We conducted this clinical trial to investigate the effects of KrocinaTM, a natural product containing crocin, on the gene expression of unique transcription factors of various T cell subsets in patients with OA. We collected 40 peripheral blood samples of OA patients receiving KrocinaTM and equal number of those who took a placebo (IRCT2015021910507N2, NCT03375814). RNA extraction was performed from the cultured peripheral blood mononuclear cells of the OA patients who received KrocinaTM and placebo and SYBR Green Real-time PCR technique was applied to assess the relative gene expression of T-bet, GATA3, ROR-gamma t, and FOXP3 as the unique transcription factors of various T cell subsets. The relative gene expression of T-bet and ROR-gamma t insignificantly decreased in the KrocinaTM receiving group as compared to the placebo group. In addition, the relative gene expressions of GATA-3 and FOXP3 after the treatment with KrocinaTM showed a significant and insignificant increase, respectively. Moreover, an insignificant decrease was observed in the gene expression of GATA-3 and FOXP3 in the placebo group. A significant and insignificant decrease in the gene expression of T-bet and ROR-gamma t was detected in the OA patients who received a placebo. GATA-3 is known as a unique transcription factor for the differentiation of T-cells to the Th2 subset. The significant increase in the gene expression of GATA-3 in the patients with OA treated with crocin may suggest the beneficial effect of crocin on shifting towards the Th2 subset and enhancing an anti-inflammatory condition.