Bone turnover markers osteocalcin

A 2-year randomized controlled study in 90 women compared the effects of oral tibolone doses of 1.25 mg/day and 2.5 mg/day on bone loss in the early postmenopausal period all took calcium 1000 mg/day. Vertebral and femoral bone density rose in both treated groups but fell in the control group, and bone turnover markers (urinary excretion of hydroxyproline/creatinine and plasma osteocalcin concentrations) were similarly affected favorably in the treated groups, as was the incidence of hot flushes/ flashes (5). Studies such as this still leave open the question of the advisability of continuing tibolone treatment over a longer period. While tibolone has indeed been shown to benefit mineral bone density, few data are available to show whether it lowers fracture incidence nor is it clear whether there is a link between tibolone and breast cancer (6). 

Biomarkers of bone turnover (serum osteocalcin, urinary DPD, serum BAP, etc.), typically included in studies with 3-6 month intervention duration, are also inconsistent in their response to soy product interventions these studies are described in more detail elsewhere (Coxam 2008). Meta-analyses of these trials revealed a moderate decrease in the bone resorption marker, urinary DPD, n = 887) but there were no effects on serum BAP or serum osteocalcin (Taku et al. 2010b). Intervention studies that include fracture as an outcome variable would be the optimum route for making conclusive assessments of the efficacy of SI in the prevention of OP, but very large numbers of participants would be required to achieve adequate statistical power. In the absence of data of this quality, the only recommendation is that including SF in the diet will not adversely affect bone health and might yield skeletal benefits in the long term. 

Kanbur, N. O., Derman, O., and Kinik, E. (2002). Osteocalcin. A biochemical marker of bone turnover during puberty. Int.. Adolesc. Med. Health 14,235-244. 

Consumption of soy foods (providing 60mg/day isoflavones) for 12 weeks by postmenopausal women has been found to significantly decrease clinical risk factors for osteoporosis (short-term markers of bone turnover) including decreased urinary M-telopeptide excretion (bone resorption marker) and increased serum osteocalcin (bone formation marker). Furthermore, consumption of a soy isoflavone supplement containing 61.8 mg of isoflavones for 4 weeks by postmenopausal Japanese women significantly decreased excretion of bone resorption markers. ... 

Glucocorticoids can even cause osteoporosis when they are used for long-term replacement therapy in the Addison s disease, as has been shown by a study of 91 patients who had taken glucocorticoids for a mean of 10.6 years, in whom bone mineral density was reduced by 32% compared with age-matched controls (SEDA-19, 377 198). However, these results contrasted with the results of a Spanish study in patients with Addison s disease, in which no direct relation was found between replacement therapy and either bone density or biochemical markers of bone turnover of calcium metabolism (alkaline phosphatase, osteocalcin, procollagen I type, parathormone, and 1,25-dihydroxycolecalciferol) (SEDA-19, 377 199). 

Elevated levels of serum alkaline phosphatase and osteocalcin are markers of bone formation and are elevated in all bone diseases that result in increased bone turnover. 

The AHRQ Report summarized numerous studies that evaluated the effects of soy products, including both protein and isoflavones, on various markers of bone health, such as bone mineral density (BMD) and biomarkers related to bone formation (bone-specific alkaline phosphatase and osteocalcin) and resorption (urinary hydroxyproline, urinary pyridinoline, and urinary deoxypyridinoline). In general, no effect of soy consumption on BMD or on biomarkers of bone formation resulted. Although a number of studies observed reductions in markers of bone resorption, these were restricted to only two biomarkers urinary pyridinoline and deoxypyridinoline. Moreover, the effects were not consistent across studies. The AHRQ report found no consistent evidence of dose-response effects for either soy isoflavones or soy protein on markers of bone turnover (Balk et al., 2005). 

Musculoskeletal In ASSERT, a multicenter, open, 96-week study, 385 antiretroviral drug-naive adults with HIV infections were randomized to either abacavir -I- lamivudine or tenofovir-I-emtricitabine with efavirenz [60 ]. There was reduced bone mineral density in both groups, but to a greater extent with the latter (hip 1.9% versus 3.6% lumbar spine 1.6% versus 2.4%). Loss of at least 6% was more common in those who took tenofovir-I-emtricitabine (13% versus 3%). Markers of bone turnover (osteocalcin, procollagen 1, N-terminal propeptide, bone-specific alkaline phosphatase, and type 1 collagen cross-linked C telopep-tide) increased in both groups during the first 24 weeks and stabilized or improved thereafter, but without complete resolution. 

Another case of priapism in a 45-year-old male on risperidone and sodium valproate is reported [267 ]. Musculoskeletal A study of risperidone-associated prolactin elevation and markers of bone turnover found that prolactin levels significantly increased and N-telopeptide cross-links (markers of bone resorption) significantly decreased [268 ]. No differences were noted between men and women osteocalcin, N-telopeptide cross-links osteocalcin ratios, oes-tradiol and testosterone did not significantly change and there were no significant associations between risperidone dose and prolactin levels. 

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