Huda Abbasi

Introduction: Rheumatoid arthritis (RA) is a chronic inflammatory condition of the joints and a leading cause of global disability. However, the use of current anti-inflammatory treatments is often limited by serious side effects and multi-organ toxicity, necessitating the exploration of safer alternatives. Objective: This study aims to investigate the anti-rheumatic potential of natural compounds of Cassia angustifolia as small-molecule inhibitors of PTGS2. Methods: The therapeutic potential of C. angustifolia was evaluated through antioxidant and antiinflammatory assays. Gas chromatography-mass spectrometry (GC-MS) was used to identify its constituents. ADMET profiling (absorption, distribution, metabolism, excretion, and toxicity), network pharmacology, and molecular dynamics simulation were employed to uncover the active compounds against PTGS2 for RA treatment. Results: C. angustifolia extract contained significant phenolic (18.2 ± 0.008 mg GAE/g DW) and flavonoid (27.57 ± 0.03 mg RE/g DW) content. GC-MS yielded 288 compounds of which four passed the toxicity parameters. Protein-protein interaction analysis revealed 10 RA-related targets, with PTGS2 emerging as the most prominent one. Molecular docking and simulations revealed that compound-2 [2-Benzo [1,3] dioxol-5- yl-8-methoxy-3-nitro-2H-chromene] and compound-4 [alpha-hydroxy-N-[2-methoxyphenyl]-benzene propanamide] binds strongly with PTGS2 (-7.7 kcal/mol and -7.9 kcal/mol, respectively) predicting its stable interaction. Conclusion: C. angustifolia compounds present a significant potential as PTGS2 inhibitors, warranting further in vitro and in vivo investigations to confirm their therapeutic efficacy against RA.

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by severe pain, inflammation, and joint deformity. Currently, it affects 1% of the population, with a projection to exceed 23 million cases by 2030. Despite significant advancements, non-steroidal anti-inflammatory drugs (NSAIDs), the first line of treatment, are associated with a range of adverse effects. Consequently, plant-based derivatives are being utilized as an effective alternative. This study evaluates the anti-inflammatory and safety profile of Colchicum luteum hydroethanolic extract (CLHE) in comparison to NSAIDs, with a focus on COX-2 and TNFα inhibition. Methods: CLHE potential was evaluated by phytochemical screening and in vitro bioactivity assays. Toxicity profile was conducted in Human Colon Epithelial Cells (HCEC) and Balb/c mice. Anti-inflammatory potential was explored in a collagen-induced arthritic (CIA) mice model. Bioactive compounds were identified computationally from GCMS data and subjected to docking and simulation studies against COX2 and TNFα. Results: CLHE demonstrated significant antioxidant (IC-50 = 6.78 µg/mL) and anti-inflammatory (IC-50 = 97.39 µg/mL) activity. It maintained 50% cell viability at 78.5 μg/µL in HCEC cells and exhibited no toxicity at a dose of 5000 mg/kg in mice. In the CIA model, CLHE significantly reduced paw swelling, arthritic scoring, C-reactive protein levels, and spleen indices, outperforming ibuprofen. Expression analysis confirmed the downregulation of COX-2, TNFα, and MMP-9. Histopathological analysis indicated the superior efficacy of CLHE compared to ibuprofen in reducing inflammation, synovial hyperplasia, and bone erosion. Computational studies identified compound-15 (CL15), (4-(4,7-dimethoxy-1,3-benzodioxol-5-yl)-2-oxo pyrrolidine-3-carboxylic acid), a non-toxic compound with strong binding affinities to COX-2 (−12.9 KJ/mol), and TNF-α (−5.8 KJ/mol). Conclusions: The findings suggest the potential of Colchicum luteum as a safer, anti-inflammatory, and multi-targeted alternative to NSAIDs for RA treatment.