TNF and rheumatoid arthritis: Infliximab reduces bone resorption and improves bone mineral content in rheumatoid arthritis by inhibiting TNF-α-induced NF-κB activation.256 In a ligature-induced periodontitis rat model, infliximab (5 mg/kg) significantly reduces alveolar bone loss, osteoclast numbers, and pro-inflammatory markers (MPO, TNF-α, IL-1β), while improving collagen fiber organization and suppressing RANK, RANKL, MMP-1, and MMP-8 expression.257