<i>Latilactobacillus sakei</i> LB-P12 Ameliorates Osteoarthritis by Reducing Cartilage Degradation and Inflammation via Regulation of NF-κB/HIF-2α Pathway

Osteoarthritis (OA) is a degenerative joint disease characterized by cartilage degradation, inflammation, and pain. Recent studies highlight the gut-joint axis, suggesting that gut microbiota influences joint health by modulating systemic inflammation and immune responses. This study investigated the effects of <i>Latilactobacillus sakei</i> LB-P12 on cartilage degradation and joint inflammation in a monosodium iodoacetate induced rat model of OA. OA severity was assessed through histological analysis, weight-bearing and micro-computed tomography (Micro-CT). Serum Interleukin 6 (IL-6) and prostaglandin E2 (PGE₂) levels, along with interleukin-1β (<i>Il1b</i>) and matrix metalloproteinase 13 (<i>Mmp13</i>) expression in knee tissue, were measured. Then, the effect of <i>L. sakei</i> LB-P12 on inflammatory responses in interleukin-1β pretreated chondrocytes has also been investigated. The <i>L. sakei</i> LB-P12 improved weight-bearing distribution and reduced cartilage damage based on histological scores. Micro-CT showed increased bone volume fraction and bone mineral density. Treatment reduced serum IL-6 and PGE₂ levels and suppressed <i>Il1b</i> and <i>Mmp13</i> expression in knee tissues. <i>In vitro</i>, <i>L. sakei</i> LB-P12 inhibited lipopolysaccharide induced pro-inflammatory cytokines and nitric oxide production in macrophages. It also downregulated the expression of <i>Epas1</i>, which encodes hypoxia-inducible factor-2α (HIF-2α), and <i>Mmp13</i> in IL-1β stimulated chondrocytes. <i>L. sakei</i> LB-P12 shows potential as a dietary supplement for alleviating OA-related pain, cartilage degradation, and inflammation by suppressing the nuclear factor-κB (NF-κB)/ HIF-2α pathway.