Effects of exercise training on serum preptin, undercarboxylated osteocalcin and high molecular weight adiponectin in adults with metabolic syndrome

The role of bone in energy metabolism: A focus on osteocalcin

Understanding the mechanisms involved in whole body glucose regulation is key for the discovery of new treatments for type 2 diabetes (T2D). Historically, glucose regulation was largely focused on responses to insulin and glucagon. Impacts of incretin-based therapies, and importance of muscle mass, are also highly relevant. Recently, bone was recognized as an endocrine organ, with several bone proteins, known as osteokines, implicated in glucose metabolism through their effects on the liver, skeletal muscle, and adipose tissue. Research efforts mostly focused on osteocalcin (OC) as a leading example. This review will provide an overview on this role of bone by discussing bone turnover markers (BTMs), the receptor activator of nuclear factor kB ligand (RANKL), osteoprotegerin (OPG), sclerostin (SCL) and lipocalin 2 (LCN2), with a focus on OC. Since 2007, some, but not all, research using mostly OC genetically modified animal models suggested undercarboxylated (uc) OC acts as a hormone involved in energy metabolism. Most data generated from in vivo, ex vivo and in vitro models, indicate that exogenous ucOC administration improves whole-body and skeletal muscle glucose metabolism. Although data in humans are generally supportive, findings are often discordant likely due to methodological differences and observational nature of that research. Overall, evidence supports the concept that bone-derived factors are involved in energy metabolism, some having beneficial effects (ucOC, OPG) others negative (RANKL, SCL), with the role of some (LCN2, other BTMs) remaining unclear. Whether the effect of osteokines on glucose regulation is clinically significant and of therapeutic value for people with insulin resistance and T2D remains to be confirmed.

Adipokine modulation in obesity: Evaluating the integrative impact of chlorella vulgaris supplementation and interval resistance training in obese males

Aims

To evaluate the effects of 12-week chlorella vulgaris (CV) combined with interval resistance training (IRT) on plasma levels of leptin, adiponectin and neuregulin-4 (Nrg-4) in obese men.

Methods

Obese men (n = 44, BMI of 32.1 ± 1.5 kg/m2) were randomly allocated to the following groups of 11 participants per group: Control Placebo group (CP), CV supplement group (CV), Interval Resistance Training group plus Placebo (IRT + P), and Interval Resistance Training plus CV supplement group (IRT + CV). IRT was performed three times a week for 12 weeks using three sets of 10 repetitions at 60 % 1RM, and integrating an active rest interval with 15 repetitions at 20 % 1RM. Participants consumed either CV (1800 mg daily) or a placebo. Pre- and post-intervention blood samples were obtained to assess adipokines which were measured by ELISA.

Results

While CV or IRT separately did not alter plasma levels of leptin (p > 0.05), their combination reduced leptin levels (p = 0.007). IRT and IRT plus CV increased the plasma levels of adiponectin and Nrg-4 (p < 0.01). An intergroup comparison indicated significant elevations of adiponectin and Nrg-4 in the CV compared to the CP group (p < 0.05).

Conclusion

The combination of IRT and CV modulates plasma levels of leptin, adiponectin and NRG4 more effectively than either IRT or CV separately in obese men.

High-Intensity Interval Versus Moderate-Intensity Continuous Exercise Training on Glycemic Control, Beta Cell Function, and Aerobic Fitness in Women with Type 2 Diabetes

Objective: This study aimed to compare the effects of High-Intensity Interval Training (HIIT) and Moderate-Intensity Continuous Training (MICT) on glycemic control, beta-cell function, and aerobic fitness in women with Type 2 Diabetes Mellitus (T2DM). Methods: Thirty-six women with T2DM were assigned equally to HIIT, MICT, and control (CON) groups. Participants in the exercise cohorts underwent a 12-week training regimen (three sessions per week), while the CON group maintained an inactive lifestyle. Glycaemia variables, beta-cell function, maximal oxygen uptake (VO2max), lipid profiles, and body composition were assessed at baseline and post-intervention. Results: Both HIIT and MICT interventions led to significant improvements in glucose, insulin, HbA1c, and insulin resistance index. Moreover, visceral adiposity index (VAI), lipid accumulation product (LAP), total cholesterol (TC), and low-density lipoprotein (LDL) levels significantly decreased in the HIIT and MICT groups after 12 weeks. Triglyceride (TG) levels decreased only after MICT, while high-density lipoprotein (HDL) levels increased after both interventions. Maximal oxygen uptake (VO2max), body mass, body mass index (BMI), and waist circumference (WC) significantly improved in all exercise groups. Notably, the HIIT group showed greater reductions in body mass compared to MICT. Nevertheless, beta-cell function remained unaltered after these two exercise regimens. Conclusion: Both HIIT and MICT interventions effectively managed T2DM in women, regardless of exercise intensity. The HIIT regimen can be considered for time-efficient lifestyle interventions in people with T2DM.

Comparative efficacy of different exercise types on inflammatory markers in women with overweight and obesity: A systematic review and network meta-analysis of randomized controlled trials

OBJECTIVES

This study aimed to compare and rank the effectiveness of aerobic exercise, resistance training, combined aerobic and resistance exercise, and high-intensity interval training on inflammatory marker levels in women with overweight and obesity by using network meta-analysis.

DESIGN

Systematic review with network meta-analysis and Grading Recommendations Assessment, Development, and Evaluation of the evidence.

METHODS

Literature as of April 2023 was searched from databases such as Cochrane, Embase, Pubmed, Web of Science, and EBSCO, and English-language randomized controlled trials that meet the inclusion criteria were selected. A random-effects network meta-analysis was performed within a frequentist framework.

RESULTS

A total of 75 articles and 4048 participants were included. Resistance training was the most recommended type of exercise to decrease C-reactive protein levels (surface under cumulative ranking = 90.1; standardized mean difference = -0.79, 95 % confidence interval: -1.17, -0.42); aerobic exercise was the most effective exercise type to reduce tumor necrosis factor-α levels (surface under cumulative ranking = 87.9; standardized mean difference = -0.79, 95 % confidence interval: -1.19, -0.39); combined aerobic and resistance exercise was the most effective type of exercise to reduce interleukin-6 levels (surface under cumulative ranking = 75.8; standardized mean difference = -0.77, 95 % confidence interval: -1.38, -0.16) and leptin levels (surface under cumulative ranking = 77.1; standardized mean difference = -0.96, 95 % confidence interval: -1.72, -0.20), and high-intensity interval training was the type of exercise that was well suited to increase adiponectin levels (surface under cumulative ranking = 87.2; standardized mean difference = 0.99, 95 % confidence interval: 0.27, 1.71).

CONCLUSIONS

This network meta-analysis based on randomized controlled trials confirmed that different exercise types have different efficacies on inflammation indicators among women with overweight and obesity. The findings may provide clinicians and healthcare professionals with insights into the implementation of exercise programs for women struggling with overweight and obesity.

The effects of combined exercise training on glucose metabolism and inflammatory markers in sedentary adults: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to determine the magnitude of the effect of combined exercise training on glucose metabolism markers, adipokines, and inflammatory cytokines in non-diabetic sedentary adults. PubMed, Web of Science, Scopus, Cochrane Library electronic databases and reference lists of included studies were explored for randomized controlled trials (RCTs) that included physically inactive adults and provided combined training interventions (aerobic plus resistance exercise). Effects on fasting glucose and insulin, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), HbA1c, adiponectin, leptin, IL-6, TNF-α, and C-reactive protein (CRP) in exercise vs control groups were analyzed using random effects meta-analysis. The Cochrane Risk of Bias Tool for Randomized Trials 2.0 (RoB 2) was used to assess the risk of bias. A total of 24 RCTs were included in the quantitative analysis. Combined exercise training significantly decrease fasting glucose (standardized mean difference, SMD: - 0.474, 95% CI [- 0.829, - 0.120], p = 0.009, 35 study arms), fasting insulin (SMD: - 1.024, 95% CI [- 1.502, - 0.545], p < 0.001, 27 study arms), HOMA-IR (SMD: - 0.946, 95% CI [- 1.450, - 0.442], p < 0.001, 23 study arms), TNF-α (SMD: - 0.972, 95% CI [- 1.361, - 0.582], p < 0.001, 10 study arms), and CRP (SMD: - 0.507, 95% CI [- 0.818, - 0.196], p = 0.001, 14 study arms). No significant effects were observed for HbA1c, adiponectin, leptin, and IL-6 levels. Random effects meta-regression models by age, sex, and intervention length were not able to explain any of the variation in the effect size of HOMA-IR. Findings from this systematic review and meta-analysis suggest that combined exercise training improves some glucose metabolism markers and inflammatory parameters in sedentary adults without diabetes.

Effect of Exercise Training on Some Anti-Inflammatory Adipokines, High Sensitivity C-Reactive Protein, and Clinical Outcomes in Sedentary Adults With Metabolic Syndrome

OBJECTIVE

This study aimed to investigate the effects of aerobic interval training and resistance training on anti-inflammatory adipokines, high sensitivity C-reactive protein, and clinical outcomes in sedentary men with metabolic syndrome.

METHODS

A total of 33 sedentary men with metabolic syndrome (age: 46.2 ± 4.6 years; body mass index: 35.4 ± 1.9 kg.m2) were randomly assigned to one of 3 groups: aerobic interval training (n = 12), resistance training (n = 10), or control (n = 11). Participants in the exercise groups completed a 12-week training program, 3 sessions per week, while those in the control group maintained their sedentary lifestyle. The levels of high sensitivity C-reactive protein (hs-CRP), omentin-1, adiponectin, lipid profiles, blood pressure, glucose metabolism, body composition, and peak oxygen uptake (VO2peak) were measured at baseline and after the intervention.

RESULTS

Both aerobic interval training and resistance training significantly improved the levels of omentin-1 and adiponectin, as well as reduced inflammation, as indicated by a decrease in hs-CRP levels. Exercise training also led to significant improvements in lipid profiles, blood pressure, glucose metabolism, and body composition. Specifically, the aerobic interval training group had significantly greater increases in high-density lipoprotein cholesterol and VO2peak, as well as greater reductions in low-density lipoprotein cholesterol, triglycerides, and total cholesterol compared to the resistance training group.

CONCLUSION

Exercise training, particularly aerobic interval training and resistance training, can be an effective non-pharmacological intervention for managing inflammation and improving cardiovascular health in metabolic syndrome patients.

Benefits of negative pressure wound therapy with fat migration during revisional total hip arthroplasty in an obese patient: A case report

INTRODUCTION

A 38-year-old African American woman presented with right hip pain and movement restriction. Her medical history included a right hip and knee arthroplasty 10 years prior, history of Slipped Capital Femoral Epiphysis and osteonecrosis of the hip. Preoperative assessment was significant for multiple comorbidities such as obesity (BMI > 38), hypertension, asthma.

PATIENT CONCERNS

The patient presented with right hip pain, rated 7/10, and restricted hip flexion, adduction, and abduction.

DIAGNOSIS

Recent imaging showed eccentric deterioration of the polyethylene lining of her prosthesis, acetabular hypertrophy on her right hip prosthesis, and chronic deformity of the pubic bone.

INTERVENTIONS

Based on these findings, a revisional total hip arthroplasty was performed. After the surgical procedure, the WoundVAC and the percutaneous drain were applied outside the tensor fascia lata to reduce seroma and hematoma formation. Postoperative pain control, antibiotics and DVT prophylaxis were given. On post-op day 3, an irrigation and debridement with delayed primary wound closure was performed under sterile conditions.

OUTCOMES

On postoperative assessment, the wound demonstrated adequate healing without any signs of infection. Sutures and staples were removed 4 weeks post-op. Upon palpation there was no edema, effusions, temperature changes, tenderness. Clinical inspection revealed symmetrical alignment of the pelvis and hips. Range of motion testing revealed restriction beyond 80 degrees upon flexion and beyond 5 degrees of adduction and 10 degrees of abduction. The surgical site was noted to be healed at 6 weeks post-op. The patient continued to do well to date, without exacerbations.

CONCLUSION

Obesity increases the risk of post-operative complications and wound healing failure. Therefore, Vacuum-assisted wound closure (WoundVAC), a type of negative pressure wound therapy, was applied outside the tensor fascia lata post-operatively, where the surgical incision was made. Negative pressure wound therapy facilitates wound healing by stimulating angiogenesis and promoting granulation tissue formation, which in turn can reduce the risk of surgical site infection in obese patients undergoing total hip arthroplasty. Highlighted is the mechanism of fat migration in the promotion of wound healing after preoperative weight loss and exercise.

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.

Effect of exercise on inflammatory markers in postmenopausal women with overweight and obesity: A systematic review and meta-analysis

IMPORTANCE

Postmenopausal women affected by overweight and obesity are susceptible to a variety of diseases due to inflammation. Exercise may reduce the risk of disease by attenuating low-grade chronic inflammation.

OBJECTIVE

We conducted a systematic review and meta-analysis to investigate the effects of exercise on inflammatory markers in postmenopausal women struggling with overweight and obesity.

METHOD

Literature as of May 2023 was searched from databases such as Cochrane, Embase, Pubmed, Web of Science, and EBSCO and English-language randomized controlled trials (RCTs) that meet the inclusion criteria were selected. Studies were included based on the following criteria: (A) Written in English; (B) RCTs; (C) Postmenopausal women impacted by overweight and obesity as research objects; (D) Outcome measurements include CRP, TNF-α, IL-6, and adiponectin; (E) Duration of the exercise intervention is eight weeks.

RESULTS

A total of 34 articles and 2229 participants were included. Exercise can significantly reduce the level of C-reactive protein (CRP) (MD: -0.59, 95 % CI: -0.87 to -0.31, p < 0.00001), tumor necrosis factor-α (TNF-α) (MD: -0.65, 95 % CI: -0.94 to -0.35, p < 0.00001), interleukin-6 (IL-6) (MD: -0.48, 95 % CI: -0.75 to -0.21, p < 0.00001), and exercise can significantly increase the level of adiponectin (MD: 0.33, 95 % CI: 0.02 to 0.65, p = 0.04) in women impacted by overweight and obesity.

CONCLUSION

These results suggest that exercise may be an effective intervention for reducing pro-inflammatory markers and increasing adiponectin in postmenopausal women impacted by overweight and obesity. The findings may provide clinicians and healthcare professionals with insights into the implementation of exercise programs for postmenopausal women living with overweight and obesity.

Evidence in Humans for Bone as an Endocrine Organ Regulating Energy Metabolism

There is increasing evidence from animal models that bone, in addition to its traditional function of providing structural support for the organism, has a rich network of interactions with multiple other tissues. This perspective focuses on evidence from human studies demonstrating that bone is an endocrine organ regulating energy metabolism, with the specific examples being osteocalcin, lipocalin 2, RANKL, and sclerostin. Conversely, animal studies have also demonstrated that a key hormone regulating energy metabolism, leptin, regulates bone metabolism via the sympathetic nervous system. Studies in humans have established a role for the sympathetic nervous system in regulating bone turnover; indeed, the potential therapeutic benefit of targeting this pathway in humans to prevent postmenopausal bone loss is currently being evaluated.

Preptin Deficiency Does Not Protect against High-Fat Diet-Induced Metabolic Dysfunction or Bone Loss in Mice

Preptin is derived from the cleavage of the E-peptide of pro-insulin-like growth factor (IGF)-II and is an insulin secretagogue. Observational studies have linked elevated circulating preptin to metabolic dysfunction in humans; however, a causal role for preptin in metabolic dysfunction has not been established. Additionally, preptin can promote osteoblast proliferation and differentiation, suggesting a link with skeletal health. We previously described a global preptin knockout (KO) model. In this study, we sought to uncover the impact of preptin KO in mice on the response to a moderately high-fat diet (HFD) and low-fat diet (LFD). HFD groups had higher weight and fat mass gain, lower trabecular and cortical bone volume and fracture load, and higher liver triglycerides. In males, preptin deficiency led to lower blood glucose than wild-type (WT) mice under LFD conditions. This was accompanied by differences in bone microarchitecture, including lower trabecular bone volume fraction, trabecular number, and lower cortical thickness. These differences were absent in female mice, although KO females had a HFD-driven increase in fat mass and liver triglycerides that was absent in WT mice. Female WT mice had increased glucose-stimulated insulin secretion under HFD conditions that was absent in female KO mice. Overall, preptin may have a detrimental impact on metabolism and a positive impact on bone health in male mice and may protect against liver fat storage in females while enabling islet compensation under HFD conditions. When we consider that serum preptin levels are elevated in humans of both sexes in pathological states in which insulin levels are elevated, the impact of preptin on comorbidity risk needs to be better understood. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Plasma and aqueous levels of subfatin, preptin and betatrophin in patients with diabetic retinopathy

AIM

To examine subfatin, preptin and betatrophin levels in plasma and aqueous in patients with diabetes mellitus (DM) (with and without retinopathy).

MATERIAL AND METHOD

Sixty patients, who were similar in terms of age and gender, and were scheduled for operation due to cataract, were included in the study. The patients were divided into three groups as Group C (20 weeks without diabetes and comorbidity), Group DM (20 patients with DM but no retinopathy) and Group DR (20 patients with diabetic retinopathy). The preoperative body mass index (BMI), fasting plasma glucose, HbA1c, lipid profile levels of all patients in the groups were examined. Blood samples were also taken for plasma subfatin, preptin and betatrophin levels. At the beginning of the cataract surgery, 0.1 ml of aqueous fluid was taken from the anterior chamber. Plasma and aqueous subfatin, preptin and betatrophin levels were analyzed by ELISA (enzyme-linked immunosorbent assays) method.

RESULTS

In our study results, there was a significant difference in BMI, fasting plasma glucose and hemoglobin A1c levels (p < 0.05 for all parameters). Plasma and aqueous subfatin levels were higher in Group DR compared to Group C (p < 0.001, p = 0.036, respectively). Plasma and aqueous preptin levels were higher in group DR and group DM than in group C (p = 0.001, p = 0.002, p < 0.001, p = 0.001, respectively). Plasma and aqueous betatrophin levels were higher in Group DR compared to group C (p = 0.001, p = 0.010, respectively).

CONCLUSION

Subfatin, preptin and betatrophin molecules may have an important role in the pathogenesis of diabetic retinopathy.

Effects of exercise training on inflammatory and cardiometabolic health markers in overweight and obese adults: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

The improvements in inflammation and cardiometabolic health play an important role in the prevention and treatment of obesity. However, the interactions between different exercise training (ET) modalities with inflammatory and cardiometabolic biomarkers are not completely understood. This systematic review and meta-analysis investigated the effects of ET on inflammatory and cardiometabolic health markers in overweight and obese adults.

EVIDENCE ACQUISITION

A systematic search was conducted in PubMed, CINAHL, MEDLINE, Cochrane, Google Scholar, Scopus and Web of Science up to December 15, 2021. Thirty-five studies including 2752 participants were included and analyzed using a random-effects model to estimate weighted mean differences (MD) with 95% confidence intervals (CI).

EVIDENCE SYNTHESIS

The meta-analysis found that ET significantly (P<0.05) increased adiponectin (WMD: 0.72 µg/mL; 95% CI: 0.60 to 0.84; SMD=0.65) and maximal oxygen consumption levels (WMD: 5.26 mL.kg.min; 95% CI: 3.84, 6.69; SMD=1.21). Moreover, ET significantly (P<0.05) reduced fasting insulin (WMD: -2.40 μIU/mL; 95% CI: -3.43 to -1.37; SMD=-0.87), fasting blood glucose (WMD: -5.41 mg/dL; 95% CI: -7.91, -2.91; SMD=-0.66), insulin resistance (WMD: -0.66; 95% CI: -1.08, -0.24; SMD=-0.66) and triglyceride levels (WMD: -10.88 mg/dL; 95% CI: -17.61, -4.15; SMD=-0.91). No significant changes were observed in interleukin-6, tumor necrosis factor-α, leptin, C-reactive protein and cholesterol concentrations. Subgroup analysis by type of training indicated that aerobic and resistance exercise had the most consistent beneficial effects as compared to other modalities.

CONCLUSIONS

Our findings suggest that ET may improve inflammation and cardiometabolic health in overweight and obese adults. Aerobic and resistance training appear to be more beneficial for improving adiponectin, fasting insulin, fasting blood glucose, insulin resistance index and triglyceride levels as compared to other exercise modalities. Further long-term studies are required to confirm and expand on these findings.

The potential anti-osteoporotic effect of exercise-induced increased preptin level in ovariectomized rats

Osteoporosis increases bone fragility and fractures. Preptin hormone is regulated by moderate exercise training and increases bone formation. Therefore, this study was conducted to see how estradiol administration and moderate exercise training affected osteoporotic changes in ovariectomized (OVX) rats. To achieve this aim, 36 healthy adult female Wistar albino rats were randomized into Sham, OVX, ovariectomized estradiol-treated (OVX + E) (OVX + E rats were treated using subcutaneous estradiol benzoate 2.5 μg/kg body weight/day), ovariectomized practicing moderate exercise training, ovariectomized estradiol-treated and practiced a moderate exercise training, and ovariectomized alendronate-treated (OVX + Alen) (OVX + Alen rats were treated orally with alendronate 3 mg/kg body weight/week) groups. Alendronate was used as a standard anti-osteoporotic drug. Moderate exercise training, including therapy with estradiol and alendronate for OVX rats began on the fourth week and lasted for six weeks. Results showed that OVX rats had estrogen and preptin deficiency in serum. These deficiencies were associated with a significant increase in bone resorption biomarkers (urinary deoxypyridinoline and hydroxyproline), and bone formation biomarkers (serum osteocalcin and bone-specific alkaline phosphatase). Also, serum pro-inflammatory cytokines (tumor necrosis factor alpha and interleukin-6) were increased, while bone osteopontin (OPN) expression was decreased. Subsequently, the osteoporotic alterations were verified based on histopathological changes. From the results, estradiol therapy and moderate exercise training significantly improved these findings to the same extent as that of the standard alendronate treatment. Therefore, through their anti-inflammatory properties, increasing bone OPN expression, and regulating serum preptin; estradiol therapy and moderate exercise training can reduce osteoporotic alterations in OVX rats. Thus, combined estradiol therapy and moderate exercise training could be a promising potential therapeutic protocol to reduce postmenopausal osteoporosis. Also, targeting serum preptin and bone osteopontin regulation could have a critical role in the treatment of postmenopausal osteoporosis.

Comparison of the Effect of Endurance, Strength and Endurance-Strength Training on Glucose and Insulin Homeostasis and the Lipid Profile of Overweight and Obese Subjects: A Systematic Review and Meta-Analysis

The most effective type of training to improve cardiometabolic parameters in overweight subjects is unknown. This meta-analysis compared the effect of endurance, strength and combined training on glucose, insulin metabolism and the lipid profile of overweight and obese adults. The Cochrane, PubMed, Scopus and Web of Science databases were searched to identify randomised trials assessing the effect of training intervention on fasting and 2 h glucose and insulin levels, glycated haemoglobin (HbA1c), homeostatic model assessment of insulin resistance (HOMA), C-peptide, total cholesterol (TC), low- (LDL-C) and high-density lipoprotein cholesterol and triglycerides (TG). Forty-six studies were included showing that endurance training more favourably reduced HbA1c (p = 0.044), and LDL-C (p = 0.021) than strength training. Endurance-strength training more effectively decreased glucose (p = 0.002), HbA1c (p = 0.032), HOMA (p = 0.002), TC (p = 0.039), LDL-C (p = 0.046), HDL (p = 0.036) and TG levels (p = 0.025) than strength training. Combined training significantly reduced the HOMA index (p = 0.009) and TG levels (p = 0.039) compared with endurance training. Endurance and endurance-strength training have a more favourable effect on glucose and insulin homeostasis and lipid profile than strength training in overweight and obese adults. However, the results from this meta-analysis should be interpreted cautiously due to significant heterogeneity among included studies.

Comparison of the Effect of Endurance, Strength, and Endurance-Strength Training on Inflammatory Markers and Adipokines Levels in Overweight and Obese Adults: Systematic Review and Meta-Analysis of Randomised Trials

The aim of this meta-analysis was to compare the effects of endurance, strength, and combined training on inflammatory markers and adipokine concentrations in overweight and obese adults. We performed a literature search of the Cochrane Library, PubMed, Scopus, and Web of Science databases and identified 24 randomised control trials published prior to June 2021. Our findings indicate that endurance training was significantly more beneficial than strength training in reducing C-reactive protein (CRP) (standard mean difference (SMD): −1.317, 95% confidence intervals (CI): −2.565, −0.070, p = 0.0385), interleukin 6 (IL-6) (SMD: −0.363, 95% CI: −0.648, −0.078, p = 0.0126), and visfatin (SMD: −0.618, 95% CI: −1.015, −0.222, p = 0.0023) concentrations. Moreover, combined training was more beneficial than strength training alone in lowering tumour necrosis factor-alpha (TNF-α) levels (SMD: 0.890, 95% CI: −0.301, 1.478, p = 0.0030). There were no differences between the effects of different types of training programmes on adiponectin and leptin concentrations. In conclusion, compared with strength training, endurance training is more effective in lowering CRP, IL-6, and visfatin concentrations, while combined training is more beneficial in reducing TNF-α levels in overweight and obese adults. Further studies are needed to determine which type of training has a better effect on adiponectin and leptin concentrations in this population.

The Effect of Endurance and Endurance-Strength Training on Bone Health and Body Composition in Centrally Obese Women-A Randomised Pilot Trial

There is no consensus exercise programme to reduce body weight and improve body composition simultaneously preventing bone loss or stimulating osteogenesis. This pilot study compared the effect of endurance and endurance-strength training on body composition and bone metabolism in centrally obese women. Recruited subjects were randomly assigned to three-month endurance (n = 22) or endurance-strength training (n = 22). Body composition, bone mineral density (BMD) and content (BMC) were assessed before and after the intervention and markers of bone formation and resorption were measured. Both training significantly decreased fat mass; however, endurance-strength training had a more favourable effect on lean mass for the gynoid area (p = 0.0211) and legs (p = 0.0381). Endurance training significantly decreased total body BMC and BMD (p = 0.0440 and p = 0.0300), whereas endurance-strength training only reduced BMD (p = 0.0063). Changes in densitometric parameters did not differ between the groups but endurance training increased osteocalcin levels (p = 0.04845), while endurance-strength training increased tartrate-resistant acid phosphatase 5b concentrations (p = 0.00145). In conclusion, both training programmes were effective in the reduction of fat mass simultaneously negatively affecting bone health. However, endurance-strength training seemed to be more effective in increasing lean mass. The study protocol was registered in the ClinicalTrials.gov database under the number NCT03444207, date of registration: 23 February 2018 (retrospective registration).

Investigation of the Relationship between the Mid_Thigh Adipose Tissue Distribution Measured by MRI and Serum Osteocalcin—A Sex-Based Approach

Osteocalcin, in its non-carboxylated form, has a positive effect on glucose metabolism. Additionally, osteocalcin levels are related to body composition, especially muscle mass. The relation to the distribution of different adipose tissue types, such as subcutaneous, intermuscular, and visceral adipose tissue, is unclear. This study aimed to investigate associations between serum osteocalcin and the distribution of subcutaneous and intermuscular adipose tissue of the mid-thigh. Furthermore, the influence of different training methods on osteocalcin levels was investigated. We performed adipose tissue quantification of subcutaneous adipose tissue (SAT) and intramuscular adipose tissue (IMAT) using MRI measurements of the mid-thigh in 128 volunteers (63 male/65 female). Laboratory analysis included blood lipid panel, serum insulin, adiponectin, and osteocalcin measurements. The main observation was a significant correlation of total serum osteocalcin (TOC) and the distribution of adipose tissue of the mid-thigh (SAT/(SAT + IMAT)) (cc = −0.29/p-value = 0.002), as well as the cross-sectional muscle area (MA), increasing with the weekly resistance training duration in males. Additionally, TOC (p-value = 0.01) and MA (p-value = 0.03) were negatively related to serum insulin. The significant relationship between TOC and SAT/(SAT + IMAT) is a new finding and confirms the negative influence of IMAT on glucose metabolism in a sex-specific approach. We could substantiate this by the negative relation of TOC with serum insulin.

Long-term effect of full-body pulsed electromagnetic field and exercise protocol in the treatment of men with osteopenia or osteoporosis: A randomized placebo-controlled trial

Background: Osteoporosis is the most prevalent metabolic disease affecting bones. Objective: To investigate the long-term effect of pulsed electromagnetic field (PEMF) combined with exercise protocol on bone mineral density (BMD) and bone markers in men with osteopenia or osteoporosis. Methods: Ninety-five males with osteopenia or osteoporosis (mean age, 51.26 ± 2.41 years; mean height, 176 ± 2.02 cm; mean weight, 83.08 ± 2.60 kg; mean body–mass index (BMI), 26.08 ± 1.09 kg/m ²) participated in the study, and they were randomly assigned to one of three groups: Group 1 received a full-body PEMF and exercise protocol (PEMF +EX), Group 2 received a placebo full-body PEMF and exercise protocol (PPEMF +EX), and Group 3 received a full-body PEMF alone (PEMF). PEMF was applied for the whole body using a full-body mat three times per week for 12 weeks, with an exercise protocol that includes flexibility, aerobic exercise, strengthening, weight-bearing, and balance exercises followed by whole-body vibration (WBV) training. Outcome measures include BMD of total hip and lumbar spine and bone markers [serum osteocalcin (s-OC), Serum amino-terminal cross-linking telopeptide of type I collagen (s-NTX), Serum carboxy-terminal cross-linking telopeptide of type I collagen (s-CTX), Parathyroid hormones (PTH), Bone-specific Alkaline Phosphatase (BSAP), and 25-hydroxy vitamin D (Vit D)]. Results: The BMD of total hip and lumbar spine was significantly increased post-treatment in all groups, and more so in Group 1 and Group 2 than Group 3. There was a significant difference in bone markers in all groups, more so in Group 1 and Group 2 than in Group 3. Conclusion: PEMF combined with exercise protocol exerts a potent role for treating OP, is more effective than exercise and PEMF alone for increasing BMD and enhancing bone formation, and suppresses bone-resorption markers after 12-weeks of treatment with the impact lasting up to 6 months.

Effect of Exercise Training on Spexin Level, Appetite, Lipid Accumulation Product, Visceral Adiposity Index, and Body Composition in Adults With Type 2 Diabetes

ObjectiveTo compare the effects of resistance and aerobic training (RT and AT) on spexin (SPX), appetite, lipid accumulation product (LAP), visceral adiposity index (VAI), and body composition in type 2 diabetes mellitus (T2DM) patients. Materials and Methods: Thirty-six T2DM men were randomized to receive RT (n = 12), AT (n = 12), or to act as a non-exercise control (CON, n = 12) 3 days a week for 12 weeks. Results: SPX was increased after both RT and AT (66.2% and 46.5%, respectively). VAI, LAP, and homeostasis model assessment-insulin resistance (HOMA-IR) were reduced in both groups, while quantitative insulin sensitivity check index (Quicki) and McAuley's indexes were increased following both interventions. However, the increases of both hunger and PFC in the RT group were greater than those of the AT. Moreover, the improvement of upper-body strength (41% vs. 10.3%) and lower-body strength (42.2% vs. 20.5%) in the RT group was greater than those of the AT. Conclusion: Our investigation shows that regardless of the modes of the regimen, a 12-week exercise intervention with RT and AT can effectively induce a significant improvement in SPX levels, appetite, LAP, VAI, and body composition in adults with T2DM.

Effects of Lifestyle Intervention on Inflammatory Markers and Waist Circumference in Overweight/Obese Adults With Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Physical inactivity and an imbalanced diet could lead to some cardio metabolic risk factors.

OBJECTIVE

The objective of this meta-analysis was to investigate the effects of lifestyle modification on inflammatory indicators and waist circumference (WC) in overweight/obese subjects with metabolic syndrome (MS).

DATA SOURCES

A systematic search was conducted in PubMed, CINAHL, MEDLINE, Cochrane, Google Scholar, and Web of Science.

STUDY SELECTION

The selection criteria were randomized controlled trials (RCTs) investigating the effects of lifestyle interventions on inflammation and WC from inception to 20 December 2020. The weighted mean difference (WMD) and 95% confidence interval (CI) between interventions were computed using a random or fixed-effects model.

RESULTS

Six RCTs (including 1246 MS patients who had, on average, overweight/obesity) met all inclusion criteria. Interventions lasted 6 to 12 months (2-5 sessions per week). Lifestyle intervention significantly reduced C-reactive protein (WMD: -0.52 mg/ml, 95% CI: -0.72, -0.33), IL-6 (WMD: -0.50 pg/ml, 95% CI: -0.56, -0.45), and increased adiponectin (WMD: 0.81 µg/ml, 95% CI, 0.64, 0.98). Moreover, lifestyle modification significantly decreased WC (WMD: -3.12 cm, 95% CI, -4.61, -1.62).

CONCLUSION

Our findings provide evidence that lifestyle alterations, including physical activity and diet, can lead to significant improvement in abdominal obesity, measured by WC and some inflammation markers among overweight/obese individuals with MS. Further high-quality research is needed to clarify the mechanisms underlying the effect of such interventions on this population's inflammatory markers.

Osteocalcin Is Independently Associated with C-Reactive Protein during Lifestyle-Induced Weight Loss in Metabolic Syndrome

Bone-derived osteocalcin has been suggested to be a metabolic regulator. To scrutinize the relation between osteocalcin and peripheral insulin sensitivity, we analyzed changes in serum osteocalcin relative to changes in insulin sensitivity, low-grade inflammation, and bone mineral density following lifestyle-induced weight loss in individuals with metabolic syndrome (MetS). Participants with MetS were randomized to a weight loss program or to a control group. Before and after the 6-month intervention period, clinical and laboratory parameters and serum osteocalcin levels were determined. Changes in body composition were analyzed by dual-energy X-ray absorptiometry (DXA). In participants of the intervention group, weight loss resulted in improved insulin sensitivity and amelioration of inflammation. Increased serum levels of osteocalcin correlated inversely with BMI (r = −0.63; p< 0.001), total fat mass (r = −0.58, p < 0.001), total lean mass (r = −0.45, p < 0.001), C-reactive protein (CRP) (r = −0.37; p < 0.01), insulin (r = −0.4; p < 0.001), leptin (r = −0.53; p < 0.001), triglycerides (r = −0.42; p < 0.001), and alanine aminotransferase (ALAT) (r = −0.52; p < 0.001). Regression analysis revealed that osteocalcin was independently associated with changes in CRP but not with changes in insulin concentration, fat mass, or bone mineral density, suggesting that weight loss-induced higher serum osteocalcin is primarily associated with reduced inflammation.

Effects of resistance training on muscle strength, insulin-like growth factor-1, and insulin-like growth factor-binding protein-3 in healthy elderly subjects: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Findings regarding the effects of resistance training (RT) on muscle strength, serum level of IGF-1, and its binding proteins are contradictory. To resolve this contradiction, we performed a systematic review and meta-analysis to investigate the effects of RT on muscle strength, the levels of serum IGF-1, and IGF-binding protein-3 in the elderly and aged.

MATERIALS AND METHODS

The PubMed, CINAHL, Medline, Google Scholar, and Scopus databases and reference lists of included studies were systematically searched to identify randomized controlled trials (RCTs) comparing subjects who underwent RT and control individuals up to May 15, 2020. This study was performed following the Preferred Items for Reporting of Systematic Reviews and Meta-Analyses guidelines. We identified and analyzed 11 eligible trials in this meta-analysis.

RESULTS

Pooled data displayed an overall significant elevation in IGF-1 (mean difference (MD): 17.34 ng/ml; 95% confidence interval (CI): 7.23, 27.46) and in muscle strength in leg press (SMD: 0.82; 95% CI: 0.30, 1.34) and bench press (SMD: 0.82; 95% CI: 0.42, 1.23) following RT. By contrast, the pooled estimate showed a non-significant elevation in IGFBP-3 (MD: 0.13 ng/ml; 95% CI: - 39.39, 39.65). Subgroup analysis revealed that the elevation in serum IGF-1 levels after RT was significant only in women (MD: 19.30 ng/ml); moreover, it increased after intervention durations of both > 12 weeks (MD: 21.98 ng/ml) and of ≤ 12 weeks (MD: 15.31 ng/ml).

CONCLUSION

RT was associated with elevated muscle strength. Moreover, RT was correlated with increased serum levels of IGF-1 among women and among those who received the training for ≤ 12 weeks or > 12 weeks. Further studies are required to elucidate the mechanisms underlying the impact of RT on IGF-1, IGFBP-3, and muscle strength.

Bone-to-Brain: A Round Trip in the Adaptation to Mechanical Stimuli

Besides the classical ones (support/protection, hematopoiesis, storage for calcium, and phosphate) multiple roles emerged for bone tissue, definitively making it an organ. Particularly, the endocrine function, and in more general terms, the capability to sense and integrate different stimuli and to send signals to other tissues, has highlighted the importance of bone in homeostasis. Bone is highly innervated and hosts all nervous system branches; bone cells are sensitive to most of neurotransmitters, neuropeptides, and neurohormones that directly affect their metabolic activity and sensitivity to mechanical stimuli. Indeed, bone is the principal mechanosensitive organ. Thanks to the mechanosensing resident cells, and particularly osteocytes, mechanical stimulation induces metabolic responses in bone forming (osteoblasts) and bone resorbing (osteoclasts) cells that allow the adaptation of the affected bony segment to the changing environment. Once stimulated, bone cells express and secrete, or liberate from the entrapping matrix, several mediators (osteokines) that induce responses on distant targets. Brain is a target of some of these mediator [e.g., osteocalcin, lipocalin2, sclerostin, Dickkopf-related protein 1 (Dkk1), and fibroblast growth factor 23], as most of them can cross the blood-brain barrier. For others, a role in brain has been hypothesized, but not yet demonstrated. As exercise effectively modifies the release and the circulating levels of these osteokines, it has been hypothesized that some of the beneficial effects of exercise on brain functions may be associated to such a bone-to-brain communication. This hypothesis hides an interesting clinical clue: may well-addressed physical activities support the treatment of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases?

Osteocalcin and its forms respond similarly to exercise in males and females

INTRODUCTION

Acute exercise increases osteocalcin (OC), a marker of bone turnover, and in particular the undercarboxylated form (ucOC). Males and females differ in baseline levels of total OC and it is thought the hormonal milieu may be driving these differences. Males and females adapt differently to the same exercise intervention, however it is unclear whether the exercise effects on OC are also sex-specific. We tested whether the responses of OC and its forms to acute High Intensity Interval Exercise (HIIE) and High Intensity Interval Training (HIIT) differed between males and females. Secondly, we examined whether sex hormones vary with OC forms within sexes to understand if these are driving factor in any potential sex differences.

METHODS

Total OC (tOC), undercarboxylated OC (ucOC), and carboxylated OC (cOC) were measured in serum of 96 healthy participants from the Gene SMART cohort (74 males and 22 females) at rest, immediately after, and 3 h after a single bout of HIIE, and at rest, 48 h after completing a four week HIIT intervention. Baseline testosterone and estradiol were also measured for a subset of the cohort (Males = 38, Females = 20). Linear mixed models were used to a) uncover the sex-specific effects of acute exercise and short-term training on OC forms and b) to examine whether the sex hormones were associated with OC levels.

RESULTS

At baseline, males had higher levels of tOC, cOC, and ucOC than females (q < 0.01). In both sexes tOC, and ucOC increased to the same extent after acute HIIE. At baseline, in males only, higher testosterone was associated with higher ucOC (β = 3.37; q < 0.046). Finally, tOC and ucOC did not change following 4 weeks of HIIT.

CONCLUSION/DISCUSSION

While there were no long-term changes in OC and its forms. tOC and ucOC were transiently enhanced after a bout of HIIE similarly in both sexes. This may be important in metabolic signalling in skeletal muscle and bone suggesting that regular exercise is needed to maintain these benefits. Overall, these data suggest that the sex differences in exercise adaptations do not extend to the bone turnover marker, OC.

The effect of exercise training on osteocalcin, adipocytokines, and insulin resistance: a systematic review and meta-analysis of randomized controlled trials

Recently, it has been reported that osteocalcin (OC), in particular its undercarboxylated (ucOC) form, is not only a bone remodeling marker but also an active hormone that intercedes glucose metabolism in humans. This study aimed to determine the impact of an exercise intervention on ucOC, adiponectin, leptin, and insulin resistance (measured by HOMA-IR). PubMed, CINAHL, Medline, Google Scholar, and Scopus databases and reference lists of included studies were searched. Twenty-two randomized controlled trials (RCTs) of exercise training impact in adults were included in the analysis. Results showed an overall significant increase in serum ucOC (MD: 0.15 ng/ml; 95% CI: 0.05 to 0.25) and adiponectin (MD: 2.83 mg/ml; 95% CI: 1.67 to 3.98), a significant decline in leptin (MD: - 4.89 pg/ml; 95% CI: - 6.94 to - 2.84), fasting glucose (MD: - 2.29 mg/dl; 95% CI: - 4.04 to - 0.54), fasting insulin (MD, - 8.90 μIU/ml; 95% CI: - 13.81 to - 3.98), and HOMA-IR (MD: - 1.96; 95% CI: - 3.11 to - 0.80). However, after removal of studies that had prescribed a balanced diet along with exercise intervention, total OC (TOC) levels also increased in the exercise group compared with the control group (MD: 0.36 ng/ml; 95% CI: 0.07 to 0.65). Our findings demonstrate that exercise-induced increases in ucOC are the probable cause of increased adiponectin. Additionally, increases in ucOC itself are probably due to changes in leptin levels and other factors, rather than its direct impact on bone and its osteoblastic activity. Further studies are required to clarify the mechanisms underlying the impact of exercise training on ucOC, adipocytokines, and insulin resistance.

Exercise Training for Pulmonary Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Pulmonary hypertension (PH) is a chronic disease with a notable health burden; regular exercise may improve specific health outcome measures.

OBJECTIVE

The objective of this meta-analysis was to estimate the effectiveness of exercise training for PH patients.

DATA SOURCES

PubMed, CINAHL, SportDiscuss and Google Scholar databases and reference lists of included studies were searched.

STUDY SELECTION

The selection criteria were randomized controlled trials (RCTs) employing an exercise training intervention. Data were extracted from the entered studies for analysis. The primary outcomes were peak oxygen uptake (VO_2peak), anaerobic threshold (AT), 6-minute walk distance (6-MWD), and quality of life (QoL) measures (physical component score and mental component score). The analysis included 9 articles with a total of 302 participants: intervention (n = 154), and control (n = 148).

RESULTS

In the pooled analysis, improvements were seen in: VO_2peak, mean difference (MD) 2.79 ml/kg/min (95% CI 2.00 to 3.59, p < 0.00001); AT, MD 107.83 ml/min (95% CI 39.64 to 176.00, p = 0.002); and 6-MWD, MD 46.67 meters (95% CI 32.39 to 60.96, p < 0.00001). Differences were found in the SF-36 physical component score MD 3.57 (95% CI 2.04 to 5.10, p < 0.00001) and the SF-36 mental component score MD 3.92 (95% CI 1.92 to 5.91, p = 0.001).

CONCLUSION

This meta-analysis demonstrates exercise training has a beneficial effect on fitness, walking performance, and self-reported QoL in PH patients.

The effect of thyroid dysfunction and treatment on adropin, asprosin and preptin levels in rats

OBJECTIVES

Thyroid hormones have important roles in normal development and energy regulating mechanisms as well as signaling mechanisms that affect energy consumption through central and peripheral pathways. The aim of this study was to determine the effects of thyroid dysfunction on adropin, asprosin and preptin levels in rat.

METHODS

The study was performed on the 38 male Wistar-albino rats. Experiment groups were designed as follows. 1-Control, 2-Hypothyroidism; To induce hypothyroidism PTU was applied by intraperitoneal as 10 mg/kg/day for 2 weeks. 3-Hypothyroidism + Thyroxine; Previously animals were made with hypothyroidism by 1 week PTU application and then 1 week l-thyroxine was given by intraperitoneal as 1.5 mg/kg/day. 4-Hyperthyroidism; Rats were made with hyperthyroidism by 3 weeks l-thyroxine (0.3 mg/kg/day). 5-Hyperthyroidism + PTU; Animals were made hyperthyroisim by l-thyroxine as groups 4, then 1 week PTU was applied to treatment of hiperthyrodism. At the end of supplementation animals were sacrificed and blood samples were collected for FT3, FT4, adropin, asprosin, preptin analysis.

RESULTS

FT3 ve FT4 levels were reduced significantly in hypothyroidism while increased in hyperthyroidism (p<0.001). Hipothyrodism led to reduces adropin, asprosin and preptin levels. And also hyperthyroidism reduced adropin and preptin levels (p<0.001).

CONCLUSIONS

The results of study show that experimental hypothyroidism and hyperthyroidism lead to significantly change to adropin, asprosin and preptin levels. However, correction of thyroid function caused to normals levels in asprosin and preptin.

Recombinant Antibodies with Unique Specificities Allow for Sensitive and Specific Detection of Uncarboxylated Osteocalcin in Human Circulation

Osteocalcin is a bone-specific protein which contains three glutamic acid residues (Glu) that undergo post-translational gamma-carboxylation. Uncarboxylated osteocalcin (ucOC) may participate in the regulation of glucose metabolism, thus measurement of ucOC could be useful in evaluating interactions between bone and glucose metabolism. We developed recombinant antibodies and immunoassay to specifically detect ucOC in human blood samples. ucOC-specific recombinant antibodies were selected from an antibody library by phage display. Four candidates were characterized, and one (Fab-AP13) was used to set up an immunoassay with a pre-existing MAb. Plasma ucOC levels were measured in subjects with normal fasting blood glucose (≤ 6 mmol/l, N = 46) or with hyperglycemia (≥ 7 mmol/l, N = 29). Further, we analyzed ucOC in age- and gender-matched patients with diagnosed type 2 diabetes (T2D, N = 49). Antibodies recognized ucOC without cross-reaction to carboxylated osteocalcin. Antibodies had unique binding sites at the carboxylation region, with Glu17 included in all epitopes. Immunoassay was set up and characterized. Immunoassay detected ucOC in serum and plasma, with on average 1.6-fold higher levels in plasma. ucOC concentrations were significantly lower in subjects with hyperglycemia (median 0.58 ng/ml, p = 0.008) or with T2D diagnosis (0.68 ng/ml, p = 0.015) than in subjects with normal blood glucose (1.01 ng/ml). ucOC negatively correlated with fasting plasma glucose in subjects without T2D (r = - 0.24, p = 0.035) but not in T2D patients (p = 0.41). Our immunoassay, based on the novel recombinant antibody, allows for specific and sensitive detection of ucOC in human circulation. Correlation between ucOC and plasma glucose suggests interactions between osteocalcin and glucose metabolism in humans.

A comparison of CrossFit and concurrent training on myonectin, insulin resistance and physical performance in healthy young women

OBJECTIVE

To compare the effect of CrossFit and concurrent aerobic + resistance training (CT) on circulating myonectin levels, insulin resistance index, and physical performance in young women.

MATERIALS AND METHODS

Thirty healthy women were randomly assigned to CrossFit (n = 16) and CT (n = 14) groups, exercising three sessions per week for eight weeks. Serum myonectin levels, insulin resistance index, body composition, and performance variables were evaluated before and after the intervention period.

RESULTS

Neither the CrossFit nor the CT group improved in myonectin levels and insulin resistance index. While, fat percentage, muscle mass, upper-limb strength, VO_2max, HR at rest, lower body mean power output, and upper body peak power output improved more after CrossFit than the CT.

CONCLUSION

It seems that CrossFit exercises by targeting multiple fitness components in one exercise session may allow participants to perform more activity in less time.

Bone Regulation of Insulin Secretion and Glucose Homeostasis

For centuries our image of the skeleton has been one of an inert structure playing a supporting role for muscles and a protective role for inner organs like the brain. Cell biology and physiology modified this view in the 20st century by defining the constant interplay between bone-forming and bone resorbing cells that take place during bone growth and remodeling, therefore demonstrating that bone is as alive as any other tissues in the body. During the past 40 years human and, most important, mouse genetics, have allowed not only the refinement of this notion by identifying the many genes and regulatory networks responsible for the crosstalk existing between bone cells, but have redefined the role of bone by showing that its influence goes way beyond its own physiology. Among its newly identified functions is the regulation of energy metabolism by 2 bone-derived hormones, osteocalcin and lipocalin-2. Their biology and respective roles in this process are the topic of this review.

Anti-Inflammatory Effects of Exercise on Metabolic Syndrome Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Increments in inflammatory indicators and low levels of physical activity are correlated to the expansion of the metabolic syndrome (MetS).

OBJECTIVE

The purpose of this study was to establish if exercise training ameliorates inflammatory status in MetS patients.

DATA SOURCES

PubMed, CINAHL, and Medline, Google Scholar, and Scopus databases and reference lists of included studies were searched.

STUDY SELECTION

Twenty randomized controlled trials (RCTs) of exercise-training impact on inflammatory markers (tumor necrosis factor (TNF) α, C-reactive protein (CRP), interleukin (IL) 6, IL-8, IL-10, and IL-18) with concurrent control groups were included in this analysis.

RESULTS

Results demonstrated an overall significant decrease in serum levels of TNF-α (mean difference (MD): -1.21 pg/ml; 95% confidence interval (CI): -1.77, -0.66), CRP (MD: -0.52 mg/l; 95% CI: -0.79, -0.25), IL-8 (MD: -1.31 pg/ml; 95% CI: -2.57, -0.06), and a significant increase in IL-10 (MD: 0.48 pg/ml; 95% CI: 0.10, 0.86). But exercise training did not change the level of IL-6 (MD: -0.69 pg/ml; 95% CI: -1.53, 0.14) and IL-18 (MD: -53.01 pg/ml; 95% CI: -166.64, 60.62).

CONCLUSION

Exercise training improves TNF-α, CRP, IL-8, and IL-10 levels in patients with MetS. For some variables, isolated aerobic exercise, and combined aerobic and resistance exercise appears to be optimal. Future research is needed to clarify the mechanisms underlying exercise training's effect on this population's inflammatory markers. More studies are required to confirm these findings.

Muscle, Bone, and Fat Crosstalk: the Biological Role of Myokines, Osteokines, and Adipokines

PURPOSE OF REVIEW

Skeletal muscle and bone are connected anatomically and physiologically, and play a crucial role in human locomotion and metabolism. Historically, the coupling between muscle and bone has been viewed in light of mechanotransduction, which dictates that the mechanical forces applied to muscle are transmitted to the skeleton to initiate bone formation. However, these organs also communicate through the endocrine system, orchestrated by a family of cytokines namely myokines (derived from myocytes) and osteokines (derived from bone cells). A third player in this biochemical crosstalk is adipose tissue and the secretion of adipokines (derived from adipocytes). In this review, we discuss the bidirectional effects of myokines and osteokines on muscle and bone metabolism, and the impact of adipokines on both of these secretory organs.

RECENT FINDINGS

Several myokines, notably, IL6, irisin, IGF-1, BDNF, myostatin, and FGF2 exert anabolic/catabolic effects on bone, while the osteokines osteocalcin and sclerostin have shown to induce muscle anabolism and catabolism, respectively. Adipokines, such as leptin, resistin, adiponectin, and TNFα (released from adipose tissue), can also modulate muscle and bone metabolism. Contrarily, exercise-mediated release of lipolytic myokines (IL6, irisin, and LIF) stimulates thermogenesis by promoting the browning of adipocytes. Myokines, osteokines, and adipokines exert autocrine/paracrine effects locally as well as through the endocrine system, to regulate muscle, bone, and fat metabolism. Reductions in physical activity and increases in energy intake, both linked with aging, leads to adipocyte hypertrophy and the recruitment of immunological cells (macrophages). In turn, this releases pro-inflammatory adipokines which induces chronic low-grade inflammation (LGI), a key player in the pathology of several diseases. However, exercise-induced stimulation of bioactive cytokines, through muscle-bone-fat crosstalk, increases muscle anabolism, bone formation, mitochondrial biogenesis, glucose utilization, and fatty acid oxidation, and attenuates chronic LGI.