Background Osteoporosis and sarcopenia are major health issues in postmenopausal women due to their high prevalence and association with several adverse outcomes. However, no biomarkers may be used for screening and diagnosis. The current study investigated potential biomarkers for osteoporosis and/or sarcopenia in postmenopausal women. Methods A cross-sectional study on 478 healthy community-dwelling postmenopausal women aged 50–90 years was performed. Osteoporosis and sarcopenia were defined according to the World Health Organization (WHO) and Asian Working Group for Sarcopenia (AWGS). Results Dehydroepiandrosterone (DHEA) was related to muscle strength (β = 0.19, p = 0.041) and function (β = 0.58, p = 0.004). Follistatin (β = − 0.27, p = 0.01) was related to muscle mass. Oxytocin (β = 0.59, p = 0.044) and DHEA (β = 0.51, p = 0.017) were related to bone mass. After adjusting for age, oxytocin (odds ratio (OR) 0.75; 95% confidence intervals (CI) 0.63–0.98; p = 0.019) was associated with osteoporosis, and DHEA (OR 0.73; 95% CI 0.51–0.96; p = 0.032) and follistatin (OR 1.66; 95% CI 1.19–3.57; p = 0.022) were associated with sarcopenia. Conclusions Postmenopausal women with sarcopenia were more likely to have lower DHEA levels and higher follistatin levels, and postmenopausal women with osteoporosis were more likely to have lower oxytocin levels.

ObjectivePTH1-34 (parathyroid hormone 1–34) is the only clinical drug to promote osteogenesis. MSCs (mesenchymal stem cells) have multidirectional differentiation potential and are closely related to fracture healing. This study was to explore the effects of PTH1-34 on proliferation and differentiation of endothelial cells and MSCs in vitro, and on angiogenesis, and MSCs migration during fracture healing in vivo.MethodsMice with stabilized fracture were assigned to 4 groups: CON, PTH (PTH1-34 40 μg/kg/day), MSC (transplanted with 105 MSCs), PTH+MSCs. Mice were sacrificed 14 days after fracture, and callus tissues were harvested for microCT scan and immunohistochemistry analysis. The effects of PTH1-34 on angiogenesis, and MSCs differentiation and migration were assessed by wound healing, tube formation and immunofluorescence staining.ResultsTreatment with either PTH1-34, or MSCs promoted bone healing and vascular formation in fracture callus. The callus bone mass, bone volume, and bone mineral density were all greater in PTH and/or MSC groups than they were in CON (p<0.05). PTH1-34 increased small vessels formation (diameter ≤50μm), whereas MSCs increased the large ones (diameter >50μm). Expression of CD31 within calluses and trabecular bones were significantly higher in PTH1-34 treated group than that of not (p<0.05). Expression of CD31, VEGFR, VEGFR2, and vWF was upregulated, and wound healing and tube formation were increased in MSCs treated with PTH1-34 compared to that of control.ConclusionsPTH1-34 improved the proliferation and differentiation of endothelial cells and MSCs, enhancing migration of MSCs to bone callus to promote angiogenesis and osteogenesis, and facilitating fracture healing.

Postmenopausal osteoporosis (PMOP) is the most common skeletal disease in postmenopausal women and has become a global public health issue. Emerging evidence demonstrated the important relationship between microRNAs and PMOP. However, miRNAs have not yet been reported in PMOP. Hence, the present study aimed to investigate the differences in miRNA expression profiles in PMOP with fragility fractures to identify the key circulating miRNAs in serum exosomes and to validate these molecules as potential biomarkers. Postmenopausal women with osteoporotic fracture and normal bone mass were enrolled. Serum exosomes were isolated by traditional differential ultracentrifugation from participants. Isolated exosomes were identified by electron microscopy, western blotting and nanoparticle-tracking analysis and then examined for exosomal small RNA sequencing. The expression of miRNAs was compared by sRNA deep sequencing and bioinformatics analysis. Three miRNAs (mir-324-3p, mir-766-3p and mir-1247-5p) were found to be associated with BMD of L1-L4, FN (femur neck) and TH (total hip), while mir-330-5p and mir-3124-5p were associated with BMD of FN and TH. Furthermore, mir-330-5p was found to promote the ALP activity of hBMSCs, while mir-3124-5p showed the opposite result. The results showed that serum exosomal miRNAs were differentially expressed in postmenopausal osteoporosis patients with fragility fractures. Our study provides the first evidence that exosomal miRNA profiling revealed aberrant circulating miRNA in postmenopausal osteoporosis. Mir-324-3p, mir-766-3p, mir-1247-5p, mir-330-5p and mir-3124-5p, which were associated with bone mineral density (BMD), may serve as candidate diagnostic biomarkers as well as potentially contribute to pathophysiology of PMOP.