Lymphatic vascular aging and age-related bone loss: current status and future perspectives.

Age-related bone loss is a major contributor to osteoporosis and fragility fractures in older adults. Skeletal aging is accompanied by reduced bone mineral density, impaired bone microarchitecture, chronic low-grade inflammation, and immune dysregulation. Lymphatic vascular aging refers to age-related structural and functional decline of lymphatic vessels. This decline impairs immune surveillance and inflammatory mediator clearance, thereby disrupting tissue homeostasis. Age-related lymphatic dysfunction impairs drainage and inflammatory clearance. This allows inflammatory mediators, including IL-6 and TNF-α, to persist in bone-associated tissues, thereby promoting osteoclastogenesis and resorption-dominant remodeling. Age-related lymphatic dysfunction also affects VEGF-C/VEGFR-3 signaling, chemokine-mediated immune trafficking, and marrow niche support. These changes link drainage failure to osteoimmune imbalance and delayed bone repair. Current evidence supports a link between lymphatic vascular dysfunction and skeletal degeneration. Most evidence comes from animal models, bone injury studies, or diseases with secondary lymphatic defects, whereas direct clinical evidence in human age-related osteoporosis remains limited. This review summarizes current evidence linking lymphatic dysfunction to skeletal degeneration, examines the context-dependent roles of lymphatic remodeling in skeletal homeostasis, and discusses emerging therapeutic strategies targeting the lymphatic-bone axis. Future studies should define clinically relevant lymphatic alterations and determine whether restoring lymphatic homeostasis can mitigate age-related bone loss.