Associations between circulating sclerostin and bone mineral density (BMD) may suggest that HIV-induces alteration in osteocyte function, according to a cross-sectional study published in Bone Reports.
Sclerostin, a bone-derived antagonist to the Wnt/β-catenin-pathway, suppresses bone remodelling and is positively associated with BMD. Additionally, certain antiretroviral therapies (ART) are associated with loss of bone mass.
These data were a subset analysis of HIV-seropositive (n=137) women enrolled in the Women’s Interagency HIV Study (WIHS), and demographically matched HIV-seronegative women (n=83), aged between 40 and 60 years. Cumulative ART exposure was categorised by class. Menopausal status was categorised into those in early premenopause and those in postmenopause.
Primary outcomes were BMD, measured by whole-body dual-energy x-ray absorptiometry (DXA) scans, at the lumbar spine, total hip, femoral neck, and distal and ultra distal radius, and circulating plasma sclerostin levels. Quantitative correlations were also determined between sclerostin with C-telopeptide of type 1 collagen (CTX), N-terminal propeptide of procollagen type 1 (P1NP), interleukin-6 (IL-6), and tumour necrosis factor alpha (TNFα).
HIV-seropositive women had significantly reduced BMD at all skeletal sites compared with HIV-seronegative women. There was no difference in circulating sclerostin levels, according to HIV-serostatus. Sclerostin was positively associated with BMD at all skeletal sites in both univariate and multivariate models adjusting for HIV status, age, BMI, and race, although the coefficients of association were attenuated in HIV-seropositive women.
Sclerostin was negatively associated with CTX and positively associated with TNFα, but not statistically associated with P1NP and IL-6.
The associations between cumulative tenofovir disoproxil fumarate (TDF) and BMD were statistically significant in the lumbar spine and ultra distal radius. Although no ART was statistically associated with sclerostin levels.
Authors conclude that activators of the Wnt/β-catenin signalling in bone may serve as a therapeutic approach among ageing individuals.