Potential Anti-inflammatory Effects of Nanocurcumin via Modulation of MicroRNA-21 and MicroRNA 34a in Osteoarthritis Patients

Background: Osteoarthritis (OA) is the most common type of arthritis, characterized by inflammation that can affect the joint structures, leading to pain and disability, and is directly linked to ageing. As an epigenetic risk factor, microRNAs (miRNAs), small non-coding RNAs, can play a role in OA pathogenesis by regulating genes involved in processes such as inflammation, apoptosis, and autophagy. Due to the unique therapeutic potential of curcumin, isolated from Curcuma longa, particularly its anti-inflammatory properties, the current study aimed to investigate the effect of nanomicelle formulation of curcumin, named SinaCurcumin®, on the expression of miRNA-21 and miRNA-34a genes in OA patients. Methods: Thirty female patients with osteoarthritis were randomly assigned to two equal groups, who received nanocurcumin (n=15) and placebo (n=15) in a double-blind clinical trial for 3 months. The gene expression levels of miRNA-21 and miRNA-34a were evaluated using the SYBR® Green Real-Time PCR method. The association between the changes in expression of miRNA-21 and miRNA-34a and the changes in clinical and laboratory indexes in OA patients was analyzed using Spearman's rank correlation. Results: In the nanocurcumin group, the gene expression of miRNA-21 and miRNA-34a was significantly reduced, while no significant changes were observed in the placebo group. Also, there was a significant positive correlation between the downregulation of miRNA-21 and miRNA-34a and a decline in clinical and laboratory indexes (Visual Analog Scale and C-reactive protein) in patients receiving nanocurcumin. Conclusion: Curcumin may provide a promising therapeutic perspective for improving inflammation in OA, through its modulatory effects on miRNA-21 and miRNA-34a.