Frontiers in Endocrinology · Nov 4, 2026
Extracellular vesicle–associated adiponectin, marrow fat, and bone density after menopause: a serum-precipitation study
By Peng Luo, Zeyang Miao, Run Xu et al.
Background: Vertebral marrow fat and circulating adiponectin are each associated with lower bone mineral density (BMD). We examined their joint pattern using an extracellular vesicle–associated adiponectin assay, operationally defined as adiponectin recovered in serum precipitates without independent confirmation of vesicle binding. Methods: This cross-sectional analysis included 193 postmenopausal women with vertebral proton density fat fraction (PDFF), BMD, body composition, and precipitate adiponectin measurements. Regression used heteroscedasticity-consistent standard errors. Sensitivity analyses added metabolic covariates and hip BMD; indirect associations were exploratory. Results: In a linear summary model, each 5-percentage-point higher PDFF corresponded to 6.5% higher extracellular vesicle–associated adiponectin (95% CI, 4.8%–8.2%); spline analysis indicated nonlinearity. The PDFF coefficient for L1–L4 BMD changed from −0.028 to −0.004 g/cm² per 5 PDFF percentage points after adiponectin adjustment (P=0.482). Adiponectin remained inversely associated with BMD (standardized beta=−0.536; 95% CI, −0.680 to −0.392), with similar metabolic sensitivity estimates. Associations with hip cross-sectional area (q=0.007) and cross-sectional moment of inertia (q=0.039) were attenuated after femoral-neck BMD adjustment (q=0.533 and 0.312). Conclusions: Operationally defined extracellular vesicle–associated adiponectin accompanied greater vertebral marrow fat and lower BMD. Vesicle binding, marrow origin, and added value beyond total adiponectin require direct testing.