The multifaceted role of acetamide derivative of chalcone: Anti-inflammatory action and impact on osteoclastogenesis, insights on NF-κB and MAPK pathway.

Inflammation is a crucial physiological response that maintains tissue homeostasis and protects against various diseases. However, in autoimmune disorders like rheumatoid arthritis (RA), chronic inflammation promotes osteoclastogenesis and progressive bone erosion. Limitations and adverse effects associated with current RA therapies including both traditional and biological DMARDs highlight the need for safer small-molecule inhibitors targeting both inflammation and osteoclast differentiation. Chalcones, naturally occurring plant-derived compounds, possess a broad spectrum of pharmacological activities, including potent anti-inflammatory properties. In the present study, chalcone derivative 7a was evaluated for its anti-inflammatory and anti-osteoclastogenic potential. In LPS-stimulated RAW 264.7 macrophages, 7a significantly inhibited nitric oxide production and reduced pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-6 while downregulating iNOS and COX-2 expression. Furthermore, 7a attenuated ROS generation while enhancing antioxidant enzyme activities; SOD and catalase. Mechanistically, 7a suppressed the phosphorylation of key proteins involved in the NF-κB and MAPK signaling pathways. In vivo, oral administration of 7a effectively reduced carrageenan-induced paw edema and normalized serum biomarkers, including LDH and CRP. In LPS-induced mice, 7a further decreased systemic TNF-α, IL-6, and IL-1β levels while restoring altered biochemical parameters such as ALP, ALT, AST, creatinine, and urea. In RANKL stimulated RAW 264.7 cells, 7a markedly inhibited osteoclastogenesis by suppressing TRAP and MMP-9 expression while modulating NF-κB/MAPK pathway activation. Importantly, 7a reduced NFATc1 and c-Fos expression, thereby disrupting the NFATc1/c-Fos axis central to osteoclast differentiation. Collectively, these findings demonstrate the promising anti-inflammatory and anti-osteoclastogenic potential of chalcone derivative 7a.