Psoralen Targets Oxidative Stress, Protein Denaturation, Microbial Triggers, and Modulates CCN1, CCN2, and TNF-α in Rheumatoid Arthritis

This study analyzed psoralen in the treatment of rheumatoid arthritis (RA) using in-silico, in-vitro, and biochemical assays for its pharmacokinetic properties, anti-inflammatory, antimicrobial effects, and cytokine regulation. The absorption–distribution–metabolism–excretion–toxicity (ADMET) analysis was performed using the pkCSM platform online. Cytotoxicity studies were conducted on SW-982 synovial cells using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium-bromide (MTT) assays, and reactive-oxygen-species (ROS) production was measured to understand the mechanisms of oxidative stress. Anti-inflammatory effects were determined by Bovine-serum-albumin (BSA) protein denaturation assays, while antimicrobial activity against Porphyromonas gingivalis, Proteus mirabilis, and Mycoplasma pneumoniae was tested by minimum-inhibitory-concentration (MIC) and minimum-microbial-concentration (MMC) assays. Molecular-docking analyzed interactions of psoralen with Tumour-Necrosis-Factor-alpha (TNF-α), Cellular Communication Network Factor-1 and -2 (CCN1, and CCN2), and quantification of their expression was achieved by Western blotting. ADMET analysis showed that psoralen had high intestinal absorption, was non-hepatotoxic, and was devoid of mutagenic and cardiovascular risks, though it had poor Central-Nervous-System (CNS) permeability. MTT assays demonstrated dose- and time-dependent cytotoxicity with IC₅₀ values of ~40 µg/mL at 24 hours and ~35 µg/mL at 48 hours, which correlated with increased ROS production. Psoralen inhibited protein denaturation following concentration-dependent manner, competing with aspirin at higher doses. It showed antimicrobial activity with MIC values of 1.5–2.5 µg/mL and MMC/MIC ratios of 1.6–2.0. The molecular-docking demonstrated strong binding with TNF-α (-8.6), CCN1 (-7.5), and CCN2 (-6.5). Significant downregulation of these mediators was further confirmed by western blot analysis. Based on these outcomes, Psoralen has potential therapeutic applications in RA thus suggesting further research studies.