Osteocalcin. A biochemical marker of bone turnover during puberty

Abstract

During bone remodelling, osteocalcin is produced by osteoblasts and its level increases during the events characterized by rapid bone turnover. Osteocalcin is a bone matrix protein, which is specific for bone metabolism and it is not influenced by metabolic bone disorders. Osteocalcin is an important marker of bone turnover in physiological and pathological conditions. Physiologically, serum osteocalcin was increased in children, particularly during the first year of life and during puberty, when evolution of the concentration was related to rapidity of physical growth. Evidence of a correlation with growth rates comes from the observation that serum osteocalcin levels parallel the height velocity curve, with higher values in childhood and during adolescence, that later fall to adult values. There are previous studies reporting that there is age-and sex-dependent change in serum osteocalcin levels in children and adolescents with a pattern resembling height velocity curves for children and serum osteocalcin elevation coincides with the pubertal growth spurt. These findings demonstrate that pubertal development and sex should be taken into account rather than chronological age when serum levels of osteocalcin are evaluated. In most of the studies relationships among osteocalcin and chronological age and bone age, but not pubertal developmental stage (sexual maturation stage) were investigated. The aim of our study was to determine whether osteocalcin is a useful marker for the pubertal growth spurt period. In this study, osteocalcin levels in male adolescents were examined in relation to their sexual maturation stage and age. According to our findings, the follow up of osteocalcin levels in relation to sexual maturation stages could be a new method to determine the phase of the pubertal growth spurt. An increase or decrease in osteocalcin levels on consecutive measurements may indicate the child's entering accelerated or decelerated stages of the growth spurt, respectively. We emphasize that the follow up of adolescent growth is made by determination of the sexual maturation stage, and not by age. Osteocalcin is a highly specific, reliable and useful marker for evaluation of the growth spurt and is not influenced by nonosseous disorders.

Bone Turnover Markers Predict Bone Mass Development in Young Adult Men: A Five-Year Longitudinal Study

“…If, as the pres- In previous studies, markers of bone turnover have been shown to correlate well with age at PHV (31,32). One small study (n ϭ 100) of males aged 10 -17 years reported a very close correlation between OC levels and the pubertal growth spurt (33). In our study, when dividing the cohort into quartiles according to OC level at baseline, men with high OC at baseline were significantly younger, weighed less, and had experienced age at PHV at a later age compared with men with low OC at baseline.…”

Bone turnover markers in the obese children – relation to gender, body composition and leptin level

“…The data based on Polish population demonstrated that the peak values of the OC level occurred much earlier in pubertal girls than in boys (between 9-13 and 10-15 years respectively) [32]. Moreover, OC seems to be a useful parameter to assess the pubertal growth spurt [13,33]. Therefore, further studies based on the larger groups of mid-pubertal obese boys are needed regarding bone turnover intensity in relation to the adipose tissue overload and adipokines production.…”

“…Puberty is a period of marked changes in the human body composition and gender differences in adiposity, fat free mass and bone density become striking [11]. A limited number of studies reported inconsistent findings on an independent cross-talk between bone turnover intensity and anthropometrical parameters and adipose tissue activity, especially in the period of pubertal development [12][13][14][15]. With respect to the dramatic rise in obesity prevalence among children and adolescents worldwide, an understanding of the links between body composition and bone metabolism during the pubertal period seems to be very important to manage potentially adverse consequences for metabolic and skeletal health in adult life.…”

Osteocalcin‐dependent regulation of glucose metabolism and fertility: Skeletal implications for the development of insulin resistance

“…OCN is the most abundant non‐collagen bone matrix protein and has been widely used as a biochemical serum marker of bone formation (Kanbur, Derman, Sen, & Kinik, ). While the precise molecular mechanisms remain unclear, OCN has been shown to control bone mineralization and to limit bone formation in mice (Ducy et al, ).…”