Osteocalcin, energy and glucose metabolism

Osteocalcin has a muscle-protective effect during weight loss in men without metabolic syndrome: a multicenter, prospective, observational study

Objective

Weight reduction often accompanies muscle loss. Existing studies highlight the involvement of osteocalcin (OC) in energy metabolism and its potential to prevent age-related muscle loss. Nevertheless, these studies predominantly involve individuals with hyperglycemia, yielding conflicting research outcomes. This study investigated the protective role of OC against muscle loss during weight reduction in individuals without metabolic syndrome (MetS).

Measures

We enrolled 130 overweight or obese individuals without MetS in a 4-month high-protein, energy-restricted dietary weight management program conducted at two clinic centers. Body composition and laboratory tests were assessed both before and after weight loss. Correlation and regression analysis were made between the changes in metabolic indicators and muscle mass during weight loss.

Results

Following weight loss, there was a decrease in body mass index (BMI), percentage of body fat (PBF), visceral fat area (VFA), fasting insulin (FINS), homeostasis model assessment insulin resistance (HOMA-IR), glycated haemoglobin (HbA1c), and lipid profile, and increase in the percentage of skeletal muscle (PSM) and vitamin D. There was no change in osteocalcin (OC) during the intervention. Correlation analysis of the relative changes in all metabolic indicators revealed a positive correlation between OC and PSM (r=0.383, p=0.002). Multiple linear regression analysis found that OC has a significant protective effect on muscles during weight loss in males after adjusting for confounding factors (β=0.089, p=0.017).

Conclusion

High-protein, energy-restricted diets demonstrate efficacy in enhancing metabolic indicators within the weight-loss population. Furthermore, OC exhibits a protective effect on muscle mass during weight reduction in individuals without MetS, with this effect being particularly evident in males.

Correlation analysis of bone metabolism indices and glycosylated hemoglobin in middle-aged and older adult patients with type 2 diabetes mellitus

This study aimed to evaluate the association between bone metabolism indices and glycated hemoglobin (HbA1c) levels in middle-aged and older adult patients with type 2 diabetes mellitus (T2DM). We retrospectively analyzed 372 T2DM patients aged > 45 years who had attended the Endocrinology Department at our hospital (males, n = 192; postmenopausal females, n = 180). We collected data concerning patient characteristics, HbA1c levels, and bone metabolism indices (25-hydroxyvitamin D [25(OH)D], β-isomerized C-terminal telopeptides, N-terminal osteocalcin [N-MID], procollagen type 1 N-terminal propeptide [P1NP], bone-specific alkaline phosphatase [BAP], calcium [Ca], and phosphorus [P]). Study patients were divided into 3 groups according to their HbA1c levels: Group A, HbA1c < 7.5%; Group B, HbA1c 7.5 to 8.9%; and Group C, HbA1c ≥ 9.0%. Pearson correlation was used to determine the correlation between HbA1c levels and the bone metabolism indices. Multiple linear regression analysis was performed to identify factors influencing HbA1c in T2DM patients. Among the 3 groups, no differences were observed in 25(OH)D, β-CTx, Ca, or P indices among the 3 groups, whereas a statistically significant difference in N-MID was observed. Pearson correlation analysis showed an inverse correlation between HbA1c levels and N-MID and no correlation with other bone metabolism indices. Multiple linear regression analysis showed that N-MID was a factor influencing HbA1c levels after adjusting for age and body mass index (BMI). Serum N-MID levels negatively correlated with HbA1c levels in middle-aged and older adult men with T2DM. Therefore, high serum N-MID levels may contribute to blood glucose control in T2DM patients.

Combined vitamin D and magnesium supplementation does not influence markers of bone turnover or glycemic control: A randomized controlled clinical trial

High-dose vitamin D supplementation can increase total osteocalcin concentrations that may reduce insulin resistance in individuals at risk for prediabetes or diabetes mellitus. Magnesium is a cofactor in vitamin D metabolism and activation. The purpose of this study was to determine the combined effect of vitamin D and magnesium supplementation on total osteocalcin concentrations, glycemic indices, and other bone turnover markers after a 12-week intervention in individuals who were overweight and obese, but otherwise healthy. We hypothesized that combined supplementation would improve serum total osteocalcin concentrations and glycemic indices more than vitamin D supplementation alone or a placebo. A total of 78 women and men completed this intervention in 3 groups: a vitamin D and magnesium group (1000 IU vitamin D₃ and 360 mg magnesium glycinate), a vitamin D group (1000 IU vitamin D₃), and a placebo group. Despite a significant increase in serum 25-hydroxyvitamin D concentrations in the vitamin D and magnesium group compared with the placebo group (difference = 5.63; CI, -10.0 to -1.21; P = .001) post-intervention, there were no differences in serum concentrations of total osteocalcin, glucose, insulin, and adiponectin or the homeostatic model assessment of insulin resistance (HOMA-IR) among groups (P > .05 for all). Additionally, total osteocalcin (β = -0.310, P = .081), bone-specific alkaline phosphatase (β = 0.004, P = .986), and C-terminal cross-linked telopeptide (β = 0.426, P = .057), were not significant predictors of HOMA-IR after the intervention. Combined supplementation was not associated with short-term improvements in glycemic indices or bone turnover markers in participants who were overweight and obese in our study. This trial was registered at clinicaltrials.gov (NCT03134417).

Assessment of Uncarboxylated Osteocalcin Levels in Type 2 Diabetes Mellitus

Osteocalcin is one of the main organic components of the bone matrix and consists of 49 amino acids excreted from osteoblastic cells in carboxylated and uncarboxylated forms. Carboxylated Osteocalcin belongs to the bone matrix, whereas uncarboxylated osteocalcin (ucOC) is an important enzyme of osteocalcin in the circulatory system. It is an essential protein for balancing the minerals in bones, binding with calcium, and regulating body glucose levels. In this review, we point out the assessment of ucOC levels in type 2 diabetes mellitus. The experimental results that show ucOC controls glucose metabolism are significant because they relate to the current obesity, diabetes, and cardiovascular disease. To confirm that, low serum levels of ucOC were a risk factor for poor glucose metabolism, and further clinical studies are required.

The Warburg effect in osteoporosis: Cellular signaling and epigenetic regulation of energy metabolic events to targeting the osteocalcin for phenotypic alteration

Osteoporosis is a silent disease of skeletal morphology that induces fragility and fracture risk in aged persons irrespective of gender. Juvenile secondary osteoporosis is rare and is influenced by familial genetic abnormalities. Despite the currently available therapeutic options, more-acute treatments are in need. Women suffer from osteoporosis after menopause, which is characterized by a decline in the secretion of sex hormones in the later phase of life. Several studies in the past two decades emphasized hormone-related pathways to combat osteoporosis. Some studies partially examined energy-related pathways, but achieving a more vivid picture of metabolism and bone remodeling in terms of the Warburg phenomenon is still warranted. Each cell requires sufficient energy for cellular propagation and growth; in particular, osteoporosis is an energy-dependent mechanism affected by a decreased cellular mass of the bone morphology. Energy utilization is the actual propagation of such diseases, and narrowing down these criteria will hopefully provide clues to formulate better therapeutic strategies. Oxidative glycolysis is a particular type of energy metabolic pathway in cancer cells that influences cellular proliferation. Therefore, the prospect of utilizing collective glucose metabolism by inducing the Warburg effect may improve cell propagation. The benefits of utilizing the energy from the Warburg effect may be a difficult task. However, it seems to improve their effectiveness in the osteoblast phenotype by connecting the selected pathways such as WNT, Notch, AKT, and Insulin signaling by targeting osteocalcin resulting in phenotypic alteration. Osteocalcin directs ATP utilization through the sclerostin SOST gene in the bone microenvironment. Thus, selective activation of ATP production involved in osteoblast maturation remains a prime strategy to fight osteoporosis.

Genetic animal modeling for idiopathic scoliosis research: history and considerations

PURPOSE

Idiopathic scoliosis (IS) is defined as a structural lateral spinal curvature ≥ 10° in otherwise healthy children and is the most common pediatric spinal deformity. IS is known to have a strong genetic component; however, the underlying etiology is still largely unknown. Animal models have been used historically to both understand and develop treatments for human disease, including within the context of IS. This intended audience for this review is clinicians in the fields of musculoskeletal surgery and research.

METHODS

In this review article, we synthesize current literature of genetic animal models of IS and introduce considerations for researchers.

RESULTS

Due to complex genetic and unique biomechanical factors (i.e., bipedalism) hypothesized to contribute to IS in humans, scoliosis is a difficult condition to replicate in model organisms.

CONCLUSION

We advocate careful selection of animal models based on the scientific question and introduce gaps and limitations in the current literature. We advocate future research efforts to include animal models with multiple characterized genetic or environmental perturbations to reflect current understanding of the human condition.

Concurrent Use of Oral Anticoagulants and Sulfonylureas in Individuals With Type 2 Diabetes and Risk of Hypoglycemia: A UK Population-Based Cohort Study

Objective

To investigate the association of concurrent use of oral anticoagulants (OACs) and sulfonylureas and the risk of hypoglycemia in individuals with type 2 diabetes mellitus (T2DM).

Research Design and Methods

A retrospective cohort study was conducted between 2001 and 2017 using electronic primary healthcare data from the IQVIA Medical Research Data (IMRD) that incorporates data supplied by The Health Improvement Network (THIN), a propriety database of Cegedim SA. Individuals with T2DM who received OAC prescription and sulfonylureas were included. We compared the risk of hypoglycemia with sulfonylureas and OACs using propensity score matching and Cox regression.

Results

109,040 individuals using warfarin and sulfonylureas and 77,296 using direct oral anticoagulants (DOACs) and sulfonylureas were identified and included. There were 285 hypoglycemia events in the warfarin with sulfonylureas group (incidence rate = 17.8 per 1,000 person-years), while in the sulfonylureas only, 304 hypoglycemia events were observed (incidence rate = 14.4 per 1,000 person-years). There were 14 hypoglycemic events in the DOACs with sulfonylureas group (incidence rates = 14.8 per 1,000 person-years), while in the sulfonylureas alone group, 60 hypoglycemia events were observed (incidence rate =23.7 per 1,000 person-years). Concurrent use of warfarin and sulfonylureas was associated with increased risk of hypoglycemia compared with sulfonylureas alone (HR 1.38; 95% CI 1.10-1.75). However, we found no evidence of an association between concurrent use of DOACs and sulfonylureas and risk of hypoglycemia (HR 0.54; 95% CI, 0.27-1.10) when compared with sulfonylureas only.

Conclusions

We provide real-world evidence of possible drug-drug interactions between warfarin and sulfonylureas. The decision to prescribe warfarin with coexistent sulfonylureas to individuals with T2DM should be carefully evaluated in the context of other risk factors of hypoglycemia, and availability of alternative medications.

Probiotic Mechanisms Affecting Glucose Homeostasis: A Scoping Review

The maintenance of a healthy status depends on the coexistence between the host organism and the microbiota. Early studies have already focused on the nutritional properties of probiotics, which may also contribute to the structural changes in the gut microbiota, thereby affecting host metabolism and homeostasis. Maintaining homeostasis in the body is therefore crucial and is reflected at all levels, including that of glucose, a simple sugar molecule that is an essential fuel for normal cellular function. Despite numerous clinical studies that have shown the effect of various probiotics on glucose and its homeostasis, knowledge about the exact function of their mechanism is still scarce. The aim of our review was to select in vivo and in vitro studies in English published in the last eleven years dealing with the effects of probiotics on glucose metabolism and its homeostasis. In this context, diverse probiotic effects at different organ levels were highlighted, summarizing their potential mechanisms to influence glucose metabolism and its homeostasis. Variations in results due to different methodological approaches were discussed, as well as limitations, especially in in vivo studies. Further studies on the interactions between probiotics, host microorganisms and their immunity are needed.

Association of Bone Metabolism Indices and Bone Mineral Density with Diabetic Retinopathy in Elderly Patients with Type 2 Diabetes Mellitus: A Cross-Sectional Inpatient Study in China

OBJECTIVE

This study is aimed at analyzing the association between bone metabolism indices and diabetic retinopathy (DR) in elderly patients with type 2 diabetes mellitus.

METHODS

Data of 352 men and 284 postmenopausal women, aged more than 50 years, with type 2 diabetes mellitus were retrospectively analyzed. Patients were divided into three groups based on the degree of DR: nondiabetic retinopathy (NDR) group, background diabetic retinopathy (BDR) group, and proliferative diabetic retinopathy (PDR) group.

RESULTS

(1) The diabetic duration and urinary albumin to creatinine ratio (UACR) were significantly higher in the PDR and BDR groups than in the NDR group (P < 0.05). The level of beta-C-terminal telopeptide (β-CTX) in male patients was lower in the PDR and BDR groups than in the NDR group (P < 0.05). In addition, the level of procollagen 1 intact N-terminal (P1NP) in female patients was higher in the PDR and BDR groups than in the NDR group (P < 0.05). (2) For men and postmenopausal women, the proportion of vitamin deficiency was higher in the PDR and BDR groups than in the NDR group (P < 0.05). (3) The logistic regression analysis in men and postmenopausal women showed that the diabetic duration and lower levels of UACR and 25(OH)D were independent risk factors for DR (P < 0.05). (4) The diabetic duration was also an independent risk factor for PDR (P < 0.05); however, no independent correlation was found between the level of 25(OH)D and PDR (P > 0.05).

CONCLUSIONS

A close association was observed between 25(OH)D level and DR in the elderly male patients and postmenopausal women with type 2 diabetes mellitus. P1NP and β-CTX levels might be closely related to DR in elderly male patients and postmenopausal women with type 2 diabetes mellitus.

Under-carboxylated osteocalcin regulates glucose and lipid metabolism during pregnancy and lactation in rats

PURPOSE

Under-carboxylated osteocalcin (UcOC), a bone-released hormone is suggested to regulate energy metabolism. Pregnancy and lactation physiological conditions that require high levels of energy. The current study attempts to examine whether UcOC is involved in regulating energy metabolism during these conditions using adult Wistar rats.

METHODS AND RESULTS

Insulin tolerance tests indicated insulin resistance during late pregnancy (day 19 of pregnancy; P19) and insulin sensitivity during early lactation (day 6 of lactation; L6). Gene expression analyses suggested that muscle glucose metabolism was downregulated during P19 and enhanced during L6. Concomitantly, circulatory UcOC levels were lower during pregnancy but higher during early lactation; the rise in UcOC levels was tightly linked to the lactation process. Altering endogenous UcOC levels pharmacologically with warfarin and alendronate in P19 and L6 rats changed whole-body insulin response and muscle glucose transporter (Glut4) expression. Glut4 expression can be increased by either UcOC or estrogen receptors (ERs), both of which act independent of each other. A high fat diet decreased UcOC levels and insulin sensitivity in lactating rats, suggesting that diet can compromise UcOC-established energy homeostasis. Gene expression of lipid metabolism markers and triglyceride levels suggested that UcOC suppression during early pregnancy is an essential step in maternal lipid storage.

CONCLUSION

Taken together, we found that UcOC plays an important role in energy homeostasis via regulation of glucose and lipid metabolism during pregnancy and lactation.

Impact of Artistic Gymnastics on Bone Formation Marker, Density and Geometry in Female Adolescents: ABCD-Growth Study

Background

To compare bone density accrual and markers of bone geometry and formation between female adolescents engaged and not engaged in artistic gymnastics (AGs).

Methods

This was a 12-month longitudinal study involving 20 female adolescents, including 10 controls and 10 gymnasts (AGs) aged 11 to 16 years. At baseline, the gymnasts had a minimum of 12 months of practice, and the controls reported no participation in any organized sport. Bone mineral density (BMD) was measured in the lower limbs, upper limbs, spine, and whole body. In addition, BMD and geometrical properties of the femur were assessed. As a bone formation marker, osteocalcin level was measured.

Results

Femoral aspects were increased in the gymnasts by 19% (P=0.009), 14% (P=0.047), and 10% (P=0.046) in the Ward's triangle, trochanter, and the overall bone, respectively, than in the control girls. Geometrical parameters, bone accrual, and osteocalcin levels were similar in both groups. The weekly training load explained 30.8% of all bone gains on the lower limbs and affected the density on parts of the femur.

Conclusions

The gymnasts, after a 12-month follow-up, demonstrated a higher BMD in the Ward's triangle and whole femur than the controls, as well as an improvement in femur density. These changes were mainly due to the weekly training load. Lastly, the gymnasts had significant bone accrual (after 12 months) in the upper limbs, lower limbs, and whole body.

Association between undercarboxylated osteocalcin, bone mineral density, and metabolic parameters in postmenopausal women

OBJECTIVE

Osteocalcin has been associated with several effects on energy and glucose metabolism. However, the physiological role of undercarboxylated osteocalcin (U-osc; the hormonally active isoform of osteocalcin) is still controversial. To correlate the serum levels of U-osc with bone mineral density (BMD) values and metabolic parameters in postmenopausal women.

SUBJECTS AND METHODS

Cross-sectional study including 105 postmenopausal women (age 56.5 ± 6.1 years, body mass index [BMI] 28.2 ± 4.9 kg/m2) grouped based on the presence of three or less, four, or five criteria of metabolic syndrome according to the International Diabetes Federation (IDF). The subjects underwent dualenergy x-ray absorptiometry (DXA) for the assessment of body composition and BMD and blood tests for the measurement of U-osc and bone-specific alkaline phosphatase (BSAP) levels.

RESULTS

The mean U-osc level was 3.1 ± 3.4 ng/mL (median 2.3 ng/mL, range 0.0-18.4 ng/mL) and the mean BSAP level was 12.9 ± 4.0 ng/mL (median 12.1 ng/mL, range 73-24.4 ng/mL). There were no associations between U-osc and BSAP levels with serum metabolic parameters. Lower fasting glucose levels were observed in participants with increased values of U-osc/femoral BMD ratio (3.61 ± 4 ng/mL versus 10.2 ± 1.6 ng/mL, p = 0.036). When the participants were stratified into tertiles according to the U-osc/ femoral BMD and U-osc/lumbar BMD ratios, lower fasting glucose levels correlated with increased ratios (p = 0.029 and p = 0.042, respectively).

CONCLUSION

Based on the ratio of U-osc to BMD, our study demonstrated an association between U-osc and glucose metabolism. However, no association was observed between U-osc and metabolic parameters.The U-osc/BMD ratio is an innovative way to correct the U-osc value for bone mass.

Correlations between serum concentration of three bone-derived factors and obesity and visceral fat accumulation in a cohort of middle aged men and women

BACKGROUND

The aim of this study was to investigate the interrelationships between three bone-derived factors [serum osteocalcin (OCN), fibroblast growth factor (FGF) 23, and neutrophil gelatinase-associated lipocalin (NGAL) levels] and body fat content and distribution, in order to reveal the potential endocrine function of bone in the development of obesity.

METHODS

We recruited 1179 people (aged 59.5 ± 6.2 years) from communities in Shanghai. Serum OCN levels were determined using an electrochemiluminescence immunoassay. Serum FGF23 and NGAL levels were determined using a sandwich enzyme-linked immunosorbent assay. The abdominal fat distribution, including visceral fat area (VFA), was assessed by magnetic resonance imaging. Visceral obesity was defined as a VFA ≥ 80 cm².

RESULTS

Serum OCN levels were inversely correlated with body fat parameters, while FGF23 and NGAL were positively correlated (P < 0.05). After adjusting for confounders, waist circumference (W) and VFA had a closer relationship with serum OCN, FGF23, and NGAL levels than body mass index (BMI) and body fat percentage (fat%, all P < 0.05). The risk of visceral obesity significantly increased with higher FGF23 and/or NGAL levels, as well as with reduced OCN levels (all P < 0.05). In addition, serum OCN, FGF23, and NGAL levels were independently associated with visceral obesity (all P < 0.01). The relationships persisted among subjects with normal glucose tolerance or subjects with hyperglycaemia (both P < 0.05).

CONCLUSIONS

Compared to the indicators of overall adiposity such as BMI or fat%, visceral adiposity indicators (W or VFA) were more closely related to serum OCN, FGF23 and NGAL levels. There was no interaction among the relationship of three bone-derived factors with visceral obesity, which revealed the independent relationship of endocrine function of skeleton with body fat.

Glucose Tolerance Tests and Osteocalcin Responses in Healthy People

Aim: Osteocalcin and undercarboxylated osteocalcin are suggested to be endocrine messengers from the bones and have been shown to stimulate insulin secretion from pancreatic β-cells. Insulin is hypothesized to increase the osteoblastic production of osteocalcin. The aim of the study was to investigate whether the route of glucose administration influence the circulating levels of osteocalcin and undercarboxylated osteocalcin. Methods: Twelve healthy males were enrolled in an acute cross-over study where they underwent an oral glucose tolerance test (OGTT), an isoglycemic intravenous glucose infusion (IIGI) and a fasting period (control). Blood samples were collected throughout 180 min and analyzed for osteocalcin and undercarboxylated osteocalcin and compared to insulin, glucose, and gastro-intestinal hormone responses. Results: Neither osteocalcin levels nor undercarboxylated osteocalcin levels over time differed between the OGTT, IIGI, and fasting. Baseline insulin levels and glucose levels were not associated with osteocalcin or undercarboxylated osteocalcin levels. Increases in insulin and glucose levels were neither associated with altered osteocalcin nor undercarboxylated osteocalcin levels. Conclusion: The route of glucose administration does not influence the circulating levels of osteocalcin and undercarboxylated osteocalcin despite the differential insulin and incretin responses. In the acute setting this suggests that insulin does not increase osteoblastic production of osteocalcin in healthy human males.

Relationships between Bone Turnover and Energy Metabolism

It is well established that diabetes can be detrimental to bone health, and its chronic complications have been associated with an increased risk of osteoporotic fracture. However, there is growing evidence that the skeleton plays a key role in a whole-organism approach to physiology. The hypothesis that bone may be involved in the regulation of physiological functions, such as insulin sensitivity and energy metabolism, has been suggested. Given the roles of insulin, adipokines, and osteocalcin in these pathways, the need for a more integrative conceptual approach to physiology is emphasized. Recent findings suggest that bone plays an important role in regulating intermediary metabolism, being possibly both a target of diabetic complications and a potential pathophysiologic factor in the disease itself. Understanding the relationships between bone turnover and glucose metabolism is important in order to develop treatments that might reestablish energy metabolism and bone health. This review describes new insights relating bone turnover and energy metabolism that have been reported in the literature.

The impact of type 2 diabetes on bone metabolism

Diabetes complications and osteoporotic fractures are two of the most important causes of morbidity and mortality in older patients and share many features including genetic susceptibility, molecular mechanisms, and environmental factors. Type 2 diabetes mellitus (T2DM) compromises bone microarchitecture by inducing abnormal bone cell function and matrix structure, with increased osteoblast apoptosis, diminished osteoblast differentiation, and enhanced osteoclast-mediated bone resorption. The linkage between these two chronic diseases creates a possibility that certain antidiabetic therapies may affect bone quality. Both glycemic and bone homeostasis are under control of common regulatory factors. These factors include insulin, accumulation of advanced glycation end products, peroxisome proliferator-activated receptor gamma, gastrointestinal hormones (such as the glucose-dependent insulinotropic peptide and the glucagon-like peptides 1 and 2), and bone-derived hormone osteocalcin. This background allows individual pharmacological targets for antidiabetic therapies to affect the bone quality due to their indirect effects on bone cell differentiation and bone remodeling process. Moreover, it's important to consider the fragility fractures as another diabetes complication and discuss more deeply about the requirement for adequate screening and preventive measures. This review aims to briefly explore the impact of T2DM on bone metabolic and mechanical proprieties and fracture risk.

Association of Serum Osteocalcin with Insulin Resistance and Coronary Atherosclerosis

Background

To determine the associations between serum osteocalcin level and insulin resistance, coronary atherosclerosis by using dual-source coronary computed tomography angiography.

Methods

A total of 98 subjects (24 men and 74 women) were selected for this retrospective cross-sectional study who voluntarily visited a health examination center for routine health check-up including the blood test for serum osteocalcin level and coronary computed tomography angiography. Multiple regression analysis was used to determine which variables were independently related to osteocalcin levels and coronary atherosclerosis.

Results

Stepwise multiple regression analysis adjusted for age, sex, menopausal status, body mass index, serum alkaline phosphatase, serum calcium and phosphate showed that osteocalcin negatively correlated with serum glucose (β=-0.145, P=0.001) and homeostasis model assessment of insulin resistance (HOMA-IR) index (β=-1.794, P=0.027) independently. The age, serum glucose, smoking status but not osteocalcin level were independent risk factors for coronary atherosclerosis by use of multiple logistic regression analysis after controlling for other variables.

Conclusions

Serum osteocalcin level was inversely associated with fasting glucose level and insulin resistance measured by HOMA-IR, suggesting that osteocalcin is important for glucose metabolism. However, in this study, no significant difference was observed in the serum osteocalcin level according to the presence of coronary atherosclerotic plaques.

THE MARKERS OF BONE METABOLISM AND SYSTEM INFLAMMATION IN PATIENTS WITH OSTEOARTHRITIS DEPENDING ON BODY MASS, THE INFLUENCE OF SYMPTOMATIC SLOW ACTING DRUGS

Aim. To assess the levels of markers of the bone synthesis and system inflammation in patients with osteoarthritis (OA) in combination with obesity and their dynamic under the influence of basic treatment. Materials and methods. The research included 40 women with OA, 46–78 years old (mean age – 59,8±1,5 years). Duration of the disease varied from 3 to 36 years (mean duration – 10,0±1,1 years). Mean body mass index (BMI) among patients was 30,6±0,7 [22,3; 39,5]kg/m2, according to which patients were divided in 3 groups: patients with OA without obesity (n=17), patients with OA with 1 degree of obesity (n=14), patients with OA with 2 degree of obesity (n=9). The level of osteochondral metabolism was assessed using quantitative measuring of the levels of procollagen IC-terminal propeptide (РІСР), (Cloud-CloneCorp. “procollagen IC-Terminal Propeptide”, USA) and osteocalcin (Roche Diagnostics «N-MID Osteocalcin», Switzerland) on analyzer «ELECSYS 2010» by the method of immune-enzyme analysis; the level of the system inflammation was assessed by the level of C-reactive protein (CRP) by the method of immunoturbidimetry. The clinical efficacy was assessed by the dynamics of intensity levels of pain syndromes at physical load and at rest by the visual-analogue scale (VAS). The measuring of РІСР, osteocalcin and CRP levels and also the assessment of clinical efficacy as to the decrease of pain syndrome were carried out twice – at the beginning and at the end of observation. The period of observation is 2 months. Results. The presence of direct correlation between РІСР and BMI (r=0,62; р=0,008) among patients with OA in combination with the normal body weight was established at the research, whereas among patients with OA in combination with obesity the analogous correlation was demonstrated between SRP and BMI (r=0,43; р=0,04) on the background of correlation of PICP and OC levels (r=0,46; р=0,03). Obesity in patients with OA was associated with the reliably higher levels of pain at both rest and physical load from the side of knee joints, with maximal intensity of the pain syndrome among patients with OA and 1 degree of obesity. Statistical analysis did not reveal the reliable dependence of РІСР and OC in patients with OA from the initial CRP level on the background of tendency to the higher РІСР level and lower OC level among patients with initially increased CRP level comparing with ones with normal CRP level. The therapy with basic preparations at OA during 2 months among patients with OA with increased CRP level led to the reliable decrease of РІСР level (р=0,0076) and the tendency to increase of OC level (р˃0,05), without the reliably significant difference between the initial and final РІСР and OC levels among patients with OA and normal CRP level. At the end of observation period the maximal analgesic effect was demonstrated as to the articulate pain at rest from the side of knee joints (р˂0,001) among patients with OA, who received diacerein, with clinically comparable effect from the side of other aticulate zones (р˂0,05), that was associated with reliable decrease of CRP level (р=0,013). Discussion. The received results testify that the control of the system inflammation level at OA is a target not only relative to the decrease of pain syndrome but also conditions the stable state of subchondral bone (SCB), providing the compensation of processes of destruction and synthesis in bone tissue. The significance of procollagen IC-terminal propeptide (РІСР) and osteocalcin (OC) as the markers of bone synthesis that are able to reflect metabolic processes in SCB at OA, and also the discordant influence of CRP level on PICP level at the relative stability of OC level were demonstrated at the research. The received results allow consider the inflammatory process at OA as a target for preservance of the bone tissue, conditioning the expedience of taking into account the ability of OA basic preparations to realize the control influence on the level of system inflammation. Diacerein that in ESCEO recommendations (2014) is related to the preparations of the 1 step of treatment of patients with OA provides the control on inflammation and stability of osteocalcin level that testifies to the balance of catabolic processes in SCB. Conclusions. At OA the levels of procollagen IC-terminal propeptide (РІСР) and osteocalcin (OC) were not associated with obesity and did not depend on the initial CRP level at the presence of correlation between РІСР level and BMI among patients with OA with the normal body weight and BMI and CRP level among patients with OA in combination with obesity. The absence of reliable dynamics from РІСР side and maintenance of the stable OC level on the background of the reliable anti-inflammatory effect at using diacerein in patients with OA can testify to the compensatory adequacy of reparation processes in SCB.

Promotion of insulin-induced glucose uptake in C2C12 myotubes by osteocalcin

A close relationship between the bone and systemic glucose metabolism has recently been the center of attention, since the uncarboxylated form of osteocalcin (GluOC), a bone-derived protein, but not the γ-carboxylated form, is involved in glucose metabolism. However, the analysis of GluOC effect using isolated organs and related cell lines are required to understand its roles in a whole systemic metabolic status. In the present study, we examined the effect of GluOC on cell lines derived from skeletal muscle to explore the mechanisms by which GluOC regulates glucose uptake. In the differentiated C2C12 myotubes, GluOC dose-dependently induced the phosphorylation of ERK without affecting intracellular cAMP and Ca(2+) levels. This effect was inhibited by U0126, an inhibitor of ERK kinase (MEK). Additionally, U73122, an inhibitor of phospholipase C tended to inhibit it as well. Furthermore, cell treatment with GluOC for a long period promoted insulin-induced Akt phosphorylation and glucose uptake in the myotubes, which was abolished by ERK signaling inhibition. These results indicate that GluOC does not triggered Akt phosphorylation and glucose uptake by itself but promotes insulin-induced glucose uptake in myotubes, probably by up-regulating Akt signaling through ERK activation.

Relationships between preptin and osteocalcin in obese, overweight, and normal weight adults

Preptin is an endocrine peptide secreted from pancreatic β cells; it acts as a physiological amplifier of glucose-mediated insulin secretion. Osteocalcin, secreted by osteoblasts, is also involved in the regulation of body energy in that it modulates fat and glucose metabolism. The aim of this study was to investigate circulating preptin and osteocalcin levels and the possible association between them in obese and overweight adults. A total of 100 obese-overweight adults and 50 healthy controls matched for age and sex were enrolled in this study. Anthropometric measurements were taken and fasting glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), lipid profile, preptin, and osteocalcin were assessed. Preptin was significantly higher in obese and overweight subjects than in controls, whereas osteocalcin was significantly lower. In multiple regression analysis, preptin was independently influenced by waist circumference (WC) (β = 3.75, P = 0.03), fasting insulin (β = 4.77, P = 0.01), HOMA-IR (β = 8.21, P = 0.003), and osteocalcin (β = -28.41, P = 0.04). Osteocalcin was independently influenced by body mass index (β = -1.46, P = 0.05), WC (β = -2.04, P = 0.03), fasting insulin (β = -2.69, P = 0.02), HOMA-IR (β = -0.19, P = 0.006), and triglyceride (β = -4.54, P = 0.001). In conclusion, elevated serum preptin and decreased osteocalcin concentrations, together with insulin resistance, are associated with obesity and overweight. Serum preptin is also independently associated with osteocalcin, which may explain, at least in part, the crosstalk between bone and the β cells of the pancreas.

The Relationship of Metabolic Syndrome and Body Composition in Children with Premature Adrenarche: Is It Age Related?

BACKGROUND

Studies that evaluate both body composition and metabolic syndrome (MeS) risk in prepubertal children with premature adrenarche (PA) are limited.

METHODS

Fifty-eight prepubertal children (aged 5-9 years, 33 female and 25 male), 30 with PA and 28 controls, were evaluated for the presence of MeS as defined by age-modified National Cholesterol Education Program Adult Treatment Panel III criteria. A subset had dual-energy X-ray absorptiometry and bone markers (n = 23/58) to evaluate the effect of hyperandrogenism on metabolic abnormalities and body composition.

RESULTS

There was no difference in the prevalence of MeS between PA and controls (p = 0.138). Children with MeS were obese with an increased waist circumference (WC) and decreased high-density lipoprotein levels. Androgens were not associated with having more than one criterion for MeS (p = 0.08) but were associated with triglycerides and WC (p = 0.029 and p = 0.041, respectively). Lean mass was greater in PA subjects (p = 0.039), and androgens correlated with bone mineral density (p = 0.029) and total body fat (p = 0.008). Subjects with a higher percent of body fat were more likely to have more than one MeS risk factor (p = 0.005).

CONCLUSIONS

MeS was seen only in obese subjects whether or not they had PA. Thus, it appears that obesity drives metabolic risk in the prepubertal population rather than PA. Our findings are important in determining how the prepubertal patient with PA should be evaluated for metabolic risk.