Advancements in understanding the role of obesity in osteoarthritis

Obesity is a major risk factor for osteoarthritis (OA), yet the precise contribution to the pathogenesis of OA is still not fully known. Although traditionally viewed as a weight-induced joint deterioration, recent studies have highlighted multiple mechanisms through which obesity contributes to OA. This review summarizes the advances in our understanding of the obesity-associated impact on OA and addresses the knowledge gaps within the field. It highlights the newest findings on the role of local and systemic factors produced by adipose tissue (AT). While AT-derived adipokines, such as leptin and resistin, have been shown to promote cartilage degradation by inducing pro-inflammatory cytokines through multiple pathways, others, like adiponectin, exert both pro- and anti-inflammatory effects. Furthermore, this review focuses on recent findings regarding the reorganization of the obesity-associated immune cell landscape during OA progression, highlighting the reduced content of synovial lining macrophages and patrolling monocytes, as well as the increased content of monocyte-derived macrophages, T cells, and myeloid suppressor cells in obese subjects. Additionally, this review explores the emerging link between the gut microbiome and metabolic dysfunction in obesity-related OA and examines the influence of sex differences on the disease. By framing OA as a systemic condition in the context of obesity, this review underscores the need for multifactorial therapeutic approaches and precision medicine strategies to address this growing public health challenge. By presenting current and emerging treatment strategies, this review features the multifaceted approach to managing and researching OA in obese populations, emphasizing the need for innovative preventative measures.