Screening and Assessment of Bone Health in Indian Women Using an Indigenous ELISA of Human Osteocalcin a Bone Turnover Marker.

Osteoporosis a major public health problem of the elderly, is associated with substantial morbidity and socio economic burden. The aim of the study was to screen women with low bone mass using the indigenously developed Osteocalcin (OC) ELISA kit and compare it with commercial ELISA kit and evaluate. The diagnostic potential of the assay was assessed in 359 samples from neighboring tertiary care hospitals over a period of 2 years. OC levels were estimated by the developed indigenous assay in samples, correlated with the Bone Mineral Density (BMD) measurements and compared by a commercial ELISA kit. On the basis of T-scores the women were stratified into Normal and case groups as Osteopenia and Osteoporosis. The serum biochemical parameters calcium and phosphorus were estimated on an auto-analyzer. To compare two different assays Bland-Altman plot and Deming linear regression analysis was performed. The prevalence of Osteopenia was high (56%) and Osteoporosis (13%) in the healthy Indian women aged 21-65 years with significant differences in OC levels in normal and women with low bone mass. Good correlation (p < 0.0001) in the OC levels by the two assays was observed. Cut off limits established earlier with indigenous assay (11.9 ng/mL and 14.9 ng/mL) for Osteopenia and Osteoporosis were similar to those with the commercial kit (13.2 ng/mL and 16.8 ng/mL) respectively. The diagnostic sensitivity, specificity and accuracy of the OC prototype was > 85%. The cost effective OC prototype can be used in screening and management of Indian women with low bone mass.

Effect of Vitamin D Levels on Bone Remodeling in Healthy Women.

BACKGROUND: Vitamin D deficiency is prevalent among Indian women. Subclinical vitamin D deficiency is a significant risk factor for osteopenia and fractures. However, its effect on bone metabolism and bone mineral density (BMD) is still debatable. OBJECTIVES: This study aimed to determine relationships of the vitamin D status with bone turnover markers, carboxy-terminal telopeptide of type-I collagen (CTX), N-terminal propeptide of type I procollagen (PINP), and BMD in healthy Indian women. METHODS: In this cross-sectional study, we determined serum levels of 25-hydroxy vitamin D (25(OH)D), parathyroid hormone, serum CTX, and PINP using commercial ELISA kits in 310 healthy Indian women aged 25 - 65 years who underwent BMD measurements with DXA scan. RESULTS: The prevalence of vitamin D deficiency was 53.87% and vitamin D insufficiency 31.29%. A direct correlation of BMD with vitamin D levels was not observed. PINP negatively correlated with vitamin D in both premenopausal (Spearman's r = -0.169, P < 0.05) and postmenopausal (Spearman's r = -0.241, P < 0.05) women. However, CTX positively correlated with vitamin D in both premenopausal (Spearman's r = 0.228, P < 0.01) and postmenopausal (Spearman's r = 0.244, P < 0.05) women. CONCLUSIONS: Vitamin D deficiency is more prevalent in premenopausal women than in postmenopausal ones. Although vitamin D does not show any association with BMD, it affects bone remodeling, which is reflected by changes in the bone formation marker PINP and the bone resorption marker CTX.

Circulating auto-antibodies against the zona pellucida and thyroid microsomal antigen in women with premature ovarian failure.

Premature ovarian failure (POF) is a disorder of multicausal etiology leading to infertility in women. Development of ovarian auto-antibodies is a causative factor in most POF cases, but no consensus on the ovarian antigenic determinants has been reached till date. In the present study, sera from 15 POF cases, seven normally cycling women and eight menopausal women were studied by immunohistochemistry (IHC) for the presence of anti-ovarian antibodies. 10 of the 15 POF sera (66.6%) presented with anti-ovarian antibodies (Ao). Of these, two demonstrated antibodies to the zona pellucida (ZP) as well as strong immunoreactivity to granulosa cells (Azg), while the remaining eight exhibited anti-ZP antibodies with negligible staining in granulosa cells (Az). The antibodies showed cross-reactivity with ZP from various species such as human, sheep, marmoset, pig and mouse. Among various murine tissues, the antibodies cross-reacted only with thyroid and not with uterus, spleen, kidney, liver, adrenal, pancreas and pituitary. Five of the eight Az individuals presented with significant titres of anti-thyroid antibodies (Azt). In the control group, one menopausal control presented with reactivity to both ZP and GC, the autoimmunity possibly being a consequence of surgical trauma; while one normally cycling woman tested positive for anti-thyroid antibodies. The IHC results were confirmed by ELISA using heat-solubilized isolated ZP (SIZP) as the antigen. Out of seven Ao samples assessed by ELISA, five reacted with SIZP. Preincubation of these five samples with varying concentrations of SIZP demonstrated a dose-dependent decrease in reactivity in ELISA and abolished staining in IHC, confirming the specificity of auto-antibodies to ZP in the POF group. Our results thus suggest that ZP is an important ovarian antigen in autoimmune POF.