Anti-Inflammatory Activity and Biochemical Modulation by Curcumin, Boswellia Serrata Extract, and Their Combination in Inflammatory Rat Models

Chronic inflammation underlies numerous debilitating conditions, including arthritis and other inflammatory disorders, where conventional treatments like NSAIDs often cause adverse effects. Natural compounds such as curcumin from Curcuma longa and boswellic acids from Boswellia serrata exhibit promising anti-inflammatory properties through complementary mechanisms—curcumin primarily inhibits NF-κB and COX-2 pathways, while boswellic acids target 5-LOX and leukotriene synthesis—suggesting potential synergism. This study evaluated the anti-inflammatory effects of curcumin (100 or 200 mg/kg), Boswellia serrata extract (100 or 200 mg/kg), and their combinations (100+100 or 200+200 mg/kg) in male Wistar rats using acute carrageenan-induced paw edema and chronic cotton pellet-induced granuloma models, with indomethacin (10 mg/kg) as a positive control. In the paw edema model, treatment dose-dependently reduced edema volume, with the high-dose combination achieving maximal inhibition (~40–50% at peak 3 h), superior to individual agents and comparable to indomethacin. In the granuloma model, the high-dose combination suppressed dry granuloma weight by 60%, outperforming monotherapy and nearing indomethacin efficacy (55.6%). Biochemical analyses revealed significant reductions in pro-inflammatory cytokines (TNF-α, IL-6, IL-1β), PGE₂, and NO levels in serum and tissues, alongside decreased oxidative stress markers (MDA) and restoration of antioxidant defences (SOD, GSH). Synergistic effects were evident in biomarker modulation, with combinations showing greater suppression than single treatments. These findings demonstrate that the combination of curcumin and Boswellia serrata exerts potent, synergistic anti-inflammatory and antioxidant activities in both acute and chronic models, supporting its potential as a safe, multi-targeted therapeutic option for inflammatory diseases.