Anti-inflammatory approach of Polypodium vulgare roots by downregulation of pro-inflammatory cytokines in complete Freund's adjuvant-induced arthritis rats.

BACKGROUND: Polypodium vulgare Linn, roots commonly used in traditional Unani medicine, has been employed to treat ailments. Despite its extensive traditional use, particularly for inflammatory conditions like arthritis, has not been fully explored. AIM OF STUDY: The study aimed to evaluate the anti-inflammatory and anti-lipoxygenase effects of a 70% ethanolic extract of Polypodium. vulgare (P. vulgare) (HEPV) roots in a complete Freund's adjuvant (CFA)-induced arthritis rat model. MATERIALS AND METHODS: Phytochemical presence was confirmed through preliminary analysis and GC-MS. Various assays, including 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) antioxidant potential, lipoxygenase inhibition, Human red blood cells membrane stabilization, and protein denaturation, were conducted. The anti-arthritic effects were evaluated in Wistar albino rats using a CFA-induced arthritis model, alongside its impact on blood parameters and pro-inflammatory cytokine mRNA expression (TNF-α and IL-6) through qRT-PCR. RESULTS: HEPV demonstrated antioxidant effect accompanied by an 50% inhibitory concentration (IC50) of 44.31 µg/ml in context of DPPH assay. At 600 µg/ml concentration, HEPV demonstrated anti-inflammatory along with anti-arthritic activity comparable to the standard Diclofenac. In a prescribed dosage of 750 mg/kg, the extract significantly reduced the rats' paw inflammation relative to the disease-specific control group. A notable decrease in arthritic score and blood C-reactive protein levels were also seen in HEPV treated groups. TNF-α, and IL-6 mRNA expression were all substantially suppressed in the experimental groups. CONCLUSION: The study provides a preclinical basis for the anti-inflammatory and anti-arthritic potential of P. vulgare, warranting further toxicological and pharmacokinetic studies to confirm its therapeutic benefits in human.