Effect of exercise on serum vitamin D and tissue vitamin D receptors in experimentally induced type 2 Diabetes Mellitus

Targeting neuroendocrine abnormalities in Parkinson's disease with exercise

Parkinson's Disease (PD) is a prevalent and complex age-related neurodegenerative condition for which there are no disease-modifying treatments currently available. The pathophysiological process underlying PD remains incompletely understood but increasing evidence points to multiple system dysfunction. Interestingly, the past decade has produced evidence that exercise not only reduces signs and symptoms of PD but is also potentially neuroprotective. Characterizing the mechanistic pathways that are triggered by exercise and lead to positive outcomes will improve understanding of how to counter disease progression and symptomatology. In this review, we highlight how exercise regulates the neuroendocrine system, whose primary role is to respond to stress, maintain homeostasis and improve resilience to aging. We focus on a group of hormones - cortisol, melatonin, insulin, klotho, and vitamin D - that have been shown to associate with various non-motor symptoms of PD, such as mood, cognition, and sleep/circadian rhythm disorder. These hormones may represent important biomarkers to track in clinical trials evaluating effects of exercise in PD with the aim of providing evidence that patients can exert some behavioral-induced control over their disease.

Association between Vitamin D Deficiency and Clinical Parameters in Men and Women Aged 50 Years or Older: A Cross-Sectional Cohort Study

Vitamin D deficiency (VDD) is increasingly prevalent on a global scale and is connected to chronic health issues including diabetes, obesity, and inflammation. This study aimed to investigate the association between VDD and various clinical parameters including glycated hemoglobin (HbA1c), body mass index (BMI), and inflammatory markers. This cross-sectional cohort study included Korean men and women aged 50 years and older (290 men, 125 women); VDD was classified as serum 25-hydroxyvitamin D (25[OH]D) levels below 20 ng/mL. Vitamin D deficiency was more prevalent in men (64.5%) compared to that in women (35.2%). Men with VDD had higher fat mass and HbA1c levels, lower muscle strength, and worse physical performance. Among women, VDD was associated with higher BMI, HbA1c, tumor necrosis factor-alpha (TNF-α), and creatinine levels. In women, 25(OH)D levels exhibited an inverse relationship with HbA1c, BMI, and TNF-α concentrations. However, there were no differences in the levels of interleukin-6 and interleukin-1 beta according to vitamin D status in both men and women. Vitamin D deficiency is linked to higher HbA1c, BMI, and inflammatory markers in older Korean women, thus warranting the maintenance of sufficient vitamin D levels for overall health.

Aerobic Exercise Ameliorates Myocardial Fibrosis via Affecting Vitamin D Receptor and Transforming Growth Factor-β1 Signaling in Vitamin D-Deficient Mice

Myocardial fibrosis is a pathological phenomenon associated with cardiovascular disease (CVD) that plays a crucial role in the development of heart diseases. Vitamin D deficiency can promote the development of CVD and exercise plays a role in the treatment of CVD. This study aimed to explore the effects of 12-week aerobic exercise training on myocardial fibrosis in vitamin D-deficient mice. A vitamin D-deficient mouse model was induced by a vitamin D-deficient (0 IU Vitamin D₃/kg) diet. Twenty-four C57BL/6J male mice were randomly divided into three groups: a control sedentary group (CONS, n = 8), a vitamin D-deficient sedentary group (VDDS, n = 8), and a vitamin D-deficient exercise group (VDDE, n = 8) which was aerobically trained for 12 weeks. The results showed that the serum 25-hydroxyvitamin D [25(OH)D] levels of the VDDS group were <50 nmol/L, which was significantly lower than that of the CONS group. Compared with the CONS group, the VDDS group showed cardiac dysfunction and significant fibrosis, together with lower vitamin D receptor (VDR) mRNA and protein expression levels, higher mRNA expression levels of profibrotic and inflammatory factors, and higher transforming growth factor-β1 (TGF-β1) and phospho-Smad2/3 (P-Smad2/3) protein expression levels. Serum 25(OH)D levels in the VDDE group were significantly higher than those in the VDDS group. Compared with the VDDS group, the VDDE group showed improved cardiac function and alleviated myocardial fibrosis. Meanwhile, the VDDE group had significantly higher VDR mRNA and protein expression levels; lower mRNA expression levels of profibrotic and inflammatory factors; and lower TGF-β1 and P-Smad2/3 protein expression levels. In conclusion, aerobic exercise training remains a promising intervention for treating myocardial fibrosis in vitamin D deficiency.

Does vitamin D supplementation improve bone health, body composition and physical performance beyond endurance exercise in patients with type 2 diabetes: A secondary analysis of randomized controlled trial

This study aimed to assess the effects of a 12-week vitamin D and endurance exercise intervention on bone health, body composition and physical performance among patients with type 2 diabetes. Totally, 61 patients were randomly assigned to vitamin D (VDG), exercise (EG), vitamin D and exercise intervention (VEG), and control (CG) groups. Bone health (bone mineral density, BMD; bone mineral content, BMC), body composition and physical performance were measured before and after the intervention. Dual energy X-ray absorptiometry was used to assess bone health and body composition. There were no additive effects of vitamin D beyond exercise were observed. Vitamin D supplementation had significant effects on maintaining bone health compared with their counterpart Total (BMC, EG + CG: 2,719.9 ± 70.0 vs. 2,670.1 ± 65.6; VDG + VEG: 2,610.9 ± 88.2 vs. 2,605.3 ± 84.8; trunk BMC, 870.2 ± 26.8 vs. 836.3 ± 23.7; 824.8 ± 29.5 vs. 822.1 ± 27.8; spine BMD, 1.15 ± 0.03 vs. 1.11 ± 0.02; 1.09 ± 0.03 vs. 1.09 ± 0.02) were observed. Exercise had a main effect on the reduction of total and trunk BF%. Patients in EG had a decreased BMC, while it was alleviated in VEG after intervention. Although no additive effect of vitamin D supplementation beyond exercise training, the supplementation had a potential effect on the prevention of bone loss induced by exercise only.

Effects of aerobic exercise on adiponectin levels potentially mediated by vitamin D in type 2 diabetic patients

Objective. The positive effects of exercise on adiponectin and vitamin D have independently been reported. Recent studies have suggested that vitamin D increases adiponectin synthesis through inhibition of the rennin-angiotensin system in adipose tissue. However, studies evaluating the effects of an aerobic exercise on adiponectin and vitamin D simultaneously investigating the potential mechanism of vitamin D-dependent adiponectin pathways in patients with type 2 diabetes mellitus (T2DM) are still limited. This study was undertaken to examine the effects of aerobic exercise on adiponectin and its association with vitamin D in patients with T2DM.

Methods. Total twenty-two patients with T2DM were randomly divided into intervention and control group. The intervention group underwent a moderate intensity of a walking mode treadmill aerobic exercise for four weeks. The exercise protocol was adapted from modified Bruce test with a periodic speed and inclination increase. In both groups, body mass index (BMI), vitamin D, and adiponectin levels, were measured before and after four weeks of the lasting program.

Results. The mean of the increased adiponectin and vitamin D levels after exercise was significantly higher in the intervened than the control group, but statistically significant difference was only found in the adiponectin effect (p=0.017). There was a significant association found between vitamin D and adiponectin in the intervention group after data adjustments to age and BMI (p=0.005).

Conclusion. Moderate intensity of treadmill exercise with increased speed and inclination periodically increased adiponectin level in patients with T2DM. The increased adiponectin might potentially be mediated by increased vitamin D, but the level of their association impact was dependent on the age and BMI.

Exercise: A Possibly Effective Way to Improve Vitamin D Nutritional Status

Vitamin D deficiency has become a widespread public health problem owing to its potential adverse health effects. Generally, the nutritional status of vitamin D depends on sunlight exposure and dietary or supplementary intake. However, recent studies have found that exercise can influence circulating 25(OH)D levels; although, the results have been inconclusive. In this review, we focused on the effect of exercise on circulating vitamin D metabolites and their possible mechanisms. We found that endurance exercise can significantly increase serum 25(OH)D levels in vitamin D-deficient people but has no significant effect on vitamin D-sufficient people. This benefit has not been observed with resistance training. Only chronic endurance exercise training can significantly increase serum 1,25(OH)₂D, and the effect may be sex-dependent. Exercise may influence 25(OH)D levels in the circulation by regulating either the vitamin D metabolites stored in tissues or the utilization by target tissues. The effects of exercise on 25(OH)D levels in the circulation may be dependent on many factors, such as the vitamin D nutritional status, exercise type and intensity, and sex. Therefore, further research on the effects and mechanisms of exercise on vitamin D metabolites is required.

Maternal vitamin D supplementation and treadmill exercise attenuated vitamin D deficiency-induced anxiety-and depressive-like behaviors in adult male offspring rats

BACKGROUND

Vitamin D is a vital neuroactive steroid for brain development and function. Vitamin D deficiency is a worldwide health problem, particularly in children and women. Gestational or developmental vitamin D deficiency is associated with an increased risk of neurodevelopmental and neuropsychiatric disorders. This study examined the effect of maternal vitamin D dietary manipulations and treadmill exercise on anxiety-and depressive-related behaviors, pro-inflammatory cytokines, and prefrontal cortex (PFC) protein levels of brain-derived neurotrophic factor (BDNF) and vitamin D receptor (VDR) in adult male offspring born to vitamin D-deficient diet (VDD)-fed dams.

METHODS AND RESULTS

Female rats were provided standard diet (SD) or VDD for six weeks and then were treated with SD (started a week before mating throughout gestation and lactation) and treadmill exercise (a week before mating until gestational day 20). Male offspring were separated on postnatal day (PND) 21 and fed SD chow until PND90. Our results demonstrated that maternal vitamin D deficiency increased anxiety and depression-related behaviors, increased levels of TNF-α and IL-1β in serum, and decreased prefrontal protein expressions of BDNF and VDR in adult male offspring. However, maternal vitamin D supplementation and treadmill exercise reversed these changes alone or in combination.

CONCLUSION

It seems that developmental vitamin D deficiency disrupts brain development and has a long-lasting effect on VDR and BDNF signaling in the rat brain resulting in neuropsychiatric disorders in offspring. Therefore, vitamin D supplementation and physical exercise are reasonable strategies to prevent these neurobehavioral impairments.

Insulin Resistance and Vitamin D Deficiency: A Link Beyond the Appearances

Vitamin D is a steroid hormone that plays a key role in the regulation of body homeostasis, including cardiovascular function. Although the chronic deficiency of vitamin D is associated with cardiovascular risk factors, as well as with an adverse prognosis, randomized controlled trials have failed in demonstrating that dietary vitamin D supplementation could ameliorate the prognosis of patients with cardiovascular diseases, and suggested that vitamin D deficiency is the expression of the effects of other determinants of cardiovascular risk. Thus, the supplementation of vitamin D is not sufficient to improve the cardiovascular risk profile and prognosis. Insulin resistance is a complex phenomenon that plays a key role in the pathogenesis of conventional cardiovascular risk factors. Interestingly, defects of vitamin D and insulin resistance have a superimposable epidemiological distribution. According to the common view, Insulin resistance is considered the direct or indirect consequence of vitamin D deficiency. However, it is also reasonable to speculate that the deficit or the impaired action of vitamin D, in some circumstances, could be the result of the same pathogenic mechanisms responsible of insulin resistance development. In this case, vitamin D deficiency could be considered an epiphenomenon of insulin resistance. Insulin resistance is a reversible condition, being possibly ameliorated by physical activity and hypocaloric diets. Notably, both physical exercise and energy-restricted dietary regimens are associated with an increase of vitamin D levels. These findings indicate that improving insulin resistance condition is a necessary step to ameliorate vitamin D supplementation-based strategies in cardiovascular prevention.

Effect of Application of Treadmill Training on Metabolic Control and Vitamin D Level in Saudi Patients with Type 2 Diabetes Mellitus

BACKGROUND

Diabetes mellitus type 2 and vitamin D deficiency are both prevalent in the Saudi Arabia. Vitamin D deficiency treatment with supplements carries a risk of intoxication.

AIM

The present study is aimed at elucidating the effect of exercise on modulation of metabolic status and vitamin D level in patients with type 2 diabetes mellitus (T2DM).

METHODS

A sum of 110 type 2 diabetic patients were voluntarily enrolled for the present investigation by dividing them into two separate groups (55 individuals for each group), the diabetic study group and diabetic control group. The diabetic study group was engaged in the training program using treadmill exercise. Laboratory parameters were monitored before and after the training program.

RESULTS

There were significant elevation in the diabetic study group compared to diabetic control group regarding postexercise vitamin D level, high-density lipoprotein (HDL) (p value ≤ 0.001, 0.045; respectively). In addition, triglycerides, low-density lipoprotein (LDL), glycosylated hemoglobin (HbA1C), and homeostatic model assessment-insulin resistance (HOMA-IR) were significantly decreased (p value < 0.001 for all mentioned parameters). Moreover, there were significant higher level in postexercise parameters as compared to preexercise level in the diabetic study group.

CONCLUSION

The exercise training program improved the metabolic control and vitamin D level after three months of intervention.

The Role of Exercise-Induced Molecular Processes and Vitamin D in Improving Cardiorespiratory Fitness and Cardiac Rehabilitation in Patients With Heart Failure

Heart failure (HF) still affects millions of people worldwide despite great advances in therapeutic approaches in the cardiovascular field. Remarkably, unlike pathological hypertrophy, exercise leads to beneficial cardiac hypertrophy characterized by normal or enhanced contractile function. Exercise-based cardiac rehabilitation improves cardiorespiratory fitness and, as a consequence, ameliorates the quality of life of patients with HF. Particularly, multiple studies demonstrated the improvement in left ventricular ejection fraction (LVEF) among patients with HF due to the various processes in the myocardium triggered by exercise. Exercise stimulates IGF-1/PI3K/Akt pathway activation involved in muscle growth in both the myocardium and skeletal muscle by regulating protein synthesis and catabolism. Also, physical activity stimulates the activation of the mitogen-activated protein kinase (MAPK) pathway which regulates cellular proliferation, differentiation and apoptosis. In addition, emerging data pointed out the anti-inflammatory effects of exercises as well. Therefore, it is of utmost importance for clinicians to accurately evaluate the patient’s condition by performing a cardiopulmonary exercise test and/or a 6-min walking test. Portable devices with the possibility to measure exercise capacity proved to be very useful in this setting as well. The aim of this review is to gather together the molecular processes triggered by the exercise and available therapies in HF settings that could ameliorate heart performance, with a special focus on strategies such as exercise-based cardiac rehabilitation.

Effect of Application of Different Exercise Intensities on Vitamin D and Parathormone in Children with Down's Syndrome

BACKGROUND

Children with Down's syndrome are more liable to vitamin D deficiency. Treating this deficiency with supplements is associated with the risk of intoxication.

AIM

The study is aimed at comparing the effect of two exercise intensities on the modulation of vitamin D and parathormone levels in children with DS.

METHODS

Forty-four DS male children aged from 8 to 12 years participated in the study. They were assigned randomly into two equal groups. Group I received high-intensity treadmill aerobic exercises, and group II received moderate-intensity T-AE, three times per week for three months. The blood samples were collected from both groups before the intervention, after one month of intervention, then after three months of intervention to assess serum 25(OH)D and PTH levels.

RESULTS

Repeated measure MANOVA revealed that the high-intensity T-AE induced a significant increase in 25(OH)D after one month and after three months while it significantly decreased PTH only after three months. Moderate-intensity T-AE had a nonsignificant effect on both hormones.

CONCLUSION

The current study concluded that the high-intensity T-AE improved both vitamin D and parathormone serum levels after three months of intervention.

Combined effects of vitamin D supplementation and endurance exercise training on insulin resistance in newly diagnosed type 2 diabetes mellitus patients with vitamin D deficiency: study protocol for a randomized controlled trial

BACKGROUND

Although approximately 50% of Chinese with type 2 diabetes mellitus (T2DM) patients have vitamin D deficiency, studies regarding vitamin D supplementation on insulin resistance (IR) have mainly focused on non-Asians. Endurance exercise training (ET) enhances insulin-mediated glucose metabolism, which plays a critical role in T2DM prevention and control. However, the combined effects of vitamin D supplementation and ET on IR in T2DM patients are unclear. The objectives of this study is to investigate the synergistic effect of vitamin D supplementation combined with exercise training intervention on IR in T2DM patients.

METHODS AND ANALYSIS

We propose a 3-month randomized controlled trial among 60 T2DM patients aged 40-65, newly diagnosed with T2DM ≤ 1 year, and with stable HbA1c level (≤ 8.0%) in the past 3 months. The participants will be randomly allocated to the vitamin D group, vitamin D combined with exercise training group, exercise training group, and control group (CG) using a computer-generated random number sequence. At baseline, participants will undergo a medical review, anthropometric measurements, dual X-ray absorptiometry, a 75-g oral glucose tolerance test (OGTT), ankle-brachial index measurements, and physical fitness measurements and will complete related lifestyle questionnaires. Fasting blood lipid and glucose levels were also measured. In a 3-month intervention period, vitamin D intervention group will receive a dose of 1000 IU daily; exercise group will perform a 1-h endurance exercise 3 times per week (maximal heart rate, 60-80%), and the control group will receive apparently identical tablets. Additionally, all participants will be advised to maintain their normal diet and physical activities during the intervention. All measurements will be repeated at 3-month follow-up after the intervention with the primary outcome measure expressed as a change from baseline in insulin sensitivity and secretion. Secondary outcome measures will compare the changes in anthropometry, ankle-brachial index, and physical fitness factors (e.g., peak oxygen uptake, hand grip strength). Data will be managed and analyzed using the Statistical Package for the Social Sciences.

DISCUSSION

This is the first study to conduct a randomized trial to clearly determine the independent and combined effects of vitamin D supplementation and endurance exercise trial on IR in Chinese T2DM patients as measured by OGTT. The findings from the proposed study will not only provide new evidences that vitamin D supplementation plays an important role in IR management but also develop a simple and efficient method to improve IR-associated metabolic diseases for T2DM patients.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR1800015383 , Registered on 28 March 2018.

Effect of Exercise-Induced Lipolysis on Serum Vitamin D Level in Obese Children: A Clinical Controlled Trial

BACKGROUND: Low Vitamin D levels associated with obesity have reached an epidemic level all over the world. It has been supposed that the low serum level of Vitamin D3 in obese subjects may be due to an increase in the uptake of Vitamin D3 by adipose tissue. AIM: The current study aimed to investigate the effect of a specially designed exercise program for boosting lipolysis on the Vitamin D level in obese children. METHODS: Thirty obese male children participated in the study. Their age was ranged from 9 to 11 years. The participants were assigned to two groups, Group I (GI) who received endurance exercise (ENE) only and Group II (GII) who received the specially designed exercise for increasing lipolysis (ENE preceded by resistance exercise). Free fatty acids (FFA), glycerol, and 25(OH)D were assessed before and immediately after exercise. RESULTS: FFA and glycerol showed a significant increase in both groups following exercise, while 25(OH)D showed a significant increase only in GII. GII showed significantly higher levels of FFA, glycerol, and 25(OH)D following exercise when it was compared to GI. CONCLUSION: The application of resistance training before ENE could improve the Vitamin D status through increasing the lipolytic activities more than the application of endurance exercise alone.

Efficacy of Vitamin D Supplementation in Addition to Aerobic Exercise Training in Obese Women with Perceived Myalgia: A Single-Blinded Randomized Controlled Clinical Trial

Obese women were more susceptible to myalgia because of their significantly lower vitamin D concentrations; the present study investigated the efficacy of vitamin D in addition to an aerobic interval training in the management of obese women with myalgia. Forty-five obese women with vitamin D deficiency and myalgia (30 to 40 years old) were assigned randomly into three equal groups. Group A received an aerobic interval training with vitamin D supplementation, Group B received vitamin D supplementation only, and Group C received aerobic interval training only; participants in all groups were on calorie deficient diets. The study outcomes were the Visual Analog Scale (VAS) for Pain Evaluation, serum vitamin D level, and Cooper 12-Minute Walk Test for Functional Capacity Evaluation, while the Short-Form Health Survey (SF) was used for assessment of quality of life. We detected a significant improvement in pain intensity level, serum vitamin D level, and quality of life in all groups with significant difference between Group A and groups B and C. We also detected a significant improvement in functional capacity in groups A and C, with no significant change in Group B. Aerobic interval training with vitamin D supplementation was more effective for the management of obese women with perceived myalgia.

Exercise acutely increases vitamin D receptor expression in T lymphocytes in vitamin D-deficient men, independent of age

NEW FINDINGS

What is the central question of this study? Does exercise affect vitamin D receptor expression in T lymphocytes in young, middle-aged and older adults? What is the main finding and its importance? Moderate-intensity cycling exercise increases vitamin D receptor expression in vitamin D-deficient men, independent of age, presenting a strategy to combat the prevalence of vitamin D deficiency.

ABSTRACT

Vitamin D plays a key role in the modulation of the immune system, mediated through the intracellular vitamin D receptor (VDR). Exercise has been shown to influence the activity and availability of the VDR. The aim of this study was to investigate the effect of age on basal immune cell (T-lymphocyte) VDR expression and the subsequent effect of acute aerobic exercise to modulate VDR expression in peripheral T cells. Thirty-five men were included in the study (mean ± SD: age 44 ± 17 years and body mass index 25.7 ± 3.1 kg/m² ), separated into three age groups: 18-30 (n = 12), 31-45 (n = 11) and 60-75 years (n = 12). Participants completed two trials [control (CON) and aerobic exercise (AE)], with blood samples collected pre- and postexercise (0, 1 and 3 h). Peripheral blood T cells were isolated and analysed for VDR expression by flow cytometry. The results show that advanced age is associated with lower VDR expression in T cells (882 ± 274, 796 ± 243 and 594 ± 174 geomean in the 18-30, 31-45 and 60-75 year age groups, respectively). Acute AE was successful at acutely increasing VDR expression in T cells, irrespective of age. Advanced age corresponds to a lower T-cell VDR expression, which might be responsible for age-associated development of chronic conditions and autoimmunity. Exercise was successful in increasing VDR expression in T cells irrespective of age and independent of exercise-induced T-cell mobilization.

Association of serum 25-hydroxy vitamin D with obesity-related indices in Chinese adults: A cross-sectional study

Obesity has been a well-known risk factor of low-level serum vitamin D. Compared with the traditional obesity-related indicator (body mass index, BMI), associations for two novel anthropometric indices, a body shape index (ABSI) and body roundness index (BRI) with vitamin D deficiency or insufficiency, still remain unclear. This study aimed to assess the associations of serum 25-hydroxy vitamin D (25(OH)D) status with these three obesity-related indices among Chinese adults. A total of 1666 individuals were included. Anthropometric measurements were performed to calculate the indices, and fasting blood was collected to determine serum 25(OH)D deficiency (<12 ng/ml) and insufficiency (12-20 ng/ml). Deficiency or insufficiency of 25(OH)D was found in 37.5% and 43.1% of the participants, respectively. After adjustment for potential confounders, a significantly increased prevalence of 25(OH)D deficiency was observed for higher ABSI (OR Q4 vs Q1 2.334, 95% CI 1.458-3.734; p trend = 0.002) and BRI (OR Q4 vs Q1 2. 215, 95%CI 1.365-3.594; p trend = 0.010), and for higher BMI in men. Regarding 25(OH)D insufficiency, a significant association was also found for ABSI (OR Q4 vs Q1 2.372, 95%CI 1.558-3.612; p trend = 0.001). The area under the ROC of ABSI (0.731, 95%CI 0.687-0.774) for predicting a low level of 25(OH)D was significantly larger than that of BMI (0.695, 95%CI 0.649-0.741) in men, but not in women. A positive association between obesity and lower 25(OH)D serum concentration was found among Chinese adults. Besides BMI, novel obesity-related indicator, ABSI and BRI were associated with lower serum 25(OH)D to some extent, and further studies are needed to clarify their potential to be used as screening tools in clinical practice.

A single bout of high-intensity exercise modulates the expression of vitamin D receptor and vitamin D-metabolising enzymes in horse skeletal muscle

BACKGROUND

The expressions of vitamin D receptor (VDR) and vitamin D-metabolising enzymes (CYP27B1 and CYP24A1) in skeletal muscle have been reported. However, the regulation of this vitamin D system in horse skeletal muscle after high-intensity exercise has not yet been elucidated.

OBJECTIVES

To investigate the effect of high-intensity exercise on the expression of vitamin D system-related proteins in horse skeletal muscle and its associations with skeletal muscle stem cell (SMSC) activity and serum 25(OH)D level.

STUDY DESIGN

Longitudinal study.

METHODS

Six healthy ponies (5 geldings, 1 mare; age 6.3 ± 2.2 years) were studied. Serum and muscle samples were taken from the jugular vein and gluteus medius respectively. Samples were collected at pre-exercise, post-exercise, 1 and 3 weeks after a single bout of high-intensity exercise. Protein expression levels of VDR, CYP27B1, CYP24A1, OxPhos and Pax7 (SMSC marker) were determined using immunohistochemical analysis. Oxidative capacity and intramuscular glycogen content were evaluated using histochemical analysis. Blood biochemistry was analysed for lactate concentration and creatine kinase (CK), and 25(OH)D activity.

RESULTS

High-intensity exercise significantly upregulated Pax7 and VDR protein expression, which correlated with significantly increased blood lactate and serum CK levels immediately post-exercise. Serum 25(OH)D₂ level correlated with CYP27B1 protein expression in skeletal muscle, and it reduced significantly immediately post-exercise and at 1 and 3 weeks post-exercise. However, CYP24A1 protein expression was unchanged throughout study periods.

MAIN LIMITATION

The healthy ponies could not represent a fit population of racehorses and eventers.

CONCLUSIONS

The rapid increase in Pax7 and VDR protein expression along with serum CK level after high-intensity exercise demonstrated an association between SMSC activity and activation of the vitamin D system in response to muscle injury in horses. Moreover, a decrease in CYP27B1 protein expression, correlated with a reduction in serum 25(OH)D₂ , may indicate a compromised vitamin D metabolism after high-intensity exercise.

Insulin-resistance and depression cohort data mining to identify nutraceutical related DNA methylation biomarker for type 2 diabetes

Insulin-resistance (IR) is one of the most important precursors of type 2 diabetes (T2D). Recent evidence suggests an association of depression with the onset of T2D. Accumulating evidence shows that depression and T2D share common biological origins, and DNA methylation examination might reveal the link between lifestyle, disease risk, and potential therapeutic targets for T2D. Here we hypothesize that integrative mining of IR and depression cohort data will facilitate predictive biomarkers identification for T2D. We utilized a newly proposed method to extract gene-level information from probe level data on genome-wide DNA methylation array. We identified a set of genes associated with IR and depression in clinical cohorts. By overlapping the IR-related nutraceutical-gene network with depression networks, we identified a common subnetwork centered with Vitamin D Receptor (VDR) gene. Preliminary clinical validation of gene methylation set in a small cohort of T2D patients and controls was established using the Sequenome matrix-assisted laser desorption ionization-time flight mass spectrometry. A set of sites in the promoter regions of VDR showed a significant difference between T2D patients and controls. Using a logistic regression model, the optimal prediction performance of these sites was AUC = 0.902，and an odds ratio = 19.76. Thus, monitoring the methylation status of specific VDR promoter region might help stratify the high-risk individuals who could potentially benefit from vitamin D dietary supplementation. Our results highlight the link between IR and depression, and the DNA methylation analysis might facilitate the search for their shared mechanisms in the etiology of T2D.

Exercise and Vitamin D Supplementation Modify Spleen Morphology in Lean, but not, in Monosodium-Glutamate-Obese Rats

We evaluated the effect of exercise and vitamin D supplementation on histological aspects of the spleens of lean and obese rats. Male Wistar rats received neonatal administration of monosodium glutamate (MSG; 4g/Kg), while Control (CON) rats received an equimolar solution. At 30 days of age, CON and MSG rats were subdivided into Exercised (E) or Sedentary (S) groups and Vitamin D (VD; 12µg/Kg) supplemented or non-supplemented (NS) groups. At the 86th day of life, rats were euthanized, and their body weights and adiposity were evaluated. Spleens were submitted to histomorphometric analysis of the white pulp (WP), germinal center (GC) and lymphatic nodule (LN). Data are presented as mean ± SEM (p<0.05). MSG treatment promoted a reduction in spleen weight, increased LN thickness and WP area, but reduced GC occupation, compared to spleens of CON-lean rats (p<0.05). Exercise and VD did not provoke changes in the spleens of MSG-obese rats. In CON-lean rats, E and VD induced augmentation of LN thickness. VD supplementation increased the WP area, while E reduced GC area occupation in spleens of CON-lean rats (p<0.05). In conclusion, exercise and VD supplementation increased LN thickness and WP area, but had the opposite effect on the GC in spleens of CON-lean rats. However, neither exercise nor VD supplementation prevented the development of morphological abnormalities in the spleens of MSG-obese rats.

The combined effect of high-intensity intermittent training and vitamin D supplementation on glycemic control in overweight and obese adults

High-intensity intermittent training (HIIT) has been shown to reduce the risk of chronic conditions including the development of type 2 diabetes mellitus (T2DM). Independently, a low vitamin D status has also been linked to the prevalence of T2DM. The aim of this study was to investigate if there was a synergistic metabolic effect of HIIT and vitamin D supplementation on glycemic control. A total of 20 male and female participants (age, 34 ± 9 year; BMI, 31.4 ± 2.8 kg·m^-2 ) completed 6 weeks HIIT, and were randomized to ingest 100 μg·day^-1 of vitamin D₃ or placebo. Response to an oral glucose tolerance test (OGTT) was determined at baseline and at 72 h postintervention. Glucose tolerance was improved as a result of the HIIT intervention, shown through a reduction in glucose and insulin concentrations during the OGTT, accompanied by a decrease in glucose (829 ± 110 to 786 ± 139 mmol·h^-1 ·L^-1 ; P = 0.043) and insulin (8101 ± 4755-7024 ± 4489 mU·h^-1 ·L^-1 ; P = 0.049) area under the curve (AUC). Supplementation increased 25-hydroxyvitamin D₃ concentration by 120% to a sufficiency status (P < 0.001). However, the consumption of vitamin D₃ seemed to attenuate the glucose response during an OGTT. Triglyceride content was lowered following the intervention (P = 0.025). There was no effect of the intervention on insulin sensitivity (IS) indices: ISI_Matsuda and HOMA-IR. Our findings demonstrate that HIIT improves glucose tolerance in nondiabetic overweight and obese adults; however vitamin D₃ supplementation did not proffer any additional positive effects on the measured indices of metabolic health.

Adapted Moderate Training Exercise Decreases the Expression of Ngal in the Rat Kidney: An Immunohistochemical Study

Neutrophil gelatinase-associated lipocalin (NGAL) is a biomarker of several injuries and is upregulated in inflammatory conditions. Vitamin D was shown to have anti-inflammatory effects and to increase after physical activity. This work aimed to assess, through immunohistochemistry, the effects of an adapted moderate training exercise (AMTE) on the expression of NGAL and vitamin D receptor (VDR) in the kidney and heart of rats. Sixteen rats were distributed into two groups: the sedentary control group and the experimental group, subjected to AMTE on the treadmill for 12 weeks. The results showed the basal expression of NGAL and VDR in both the heart and the kidney in sedentary rats; no differences in the expression of both NGAL and VDR in the heart; and a decreased NGAL and an increased VDR expression in the kidney of rats subjected to AMTE. These results suggest a possible protective role of AMTE on NGAL-associated injuries in the kidney, probably through the vitamin D signaling pathway. Our results represent an interesting preliminary data that may open new horizons in the management of NGAL-associated kidney injuries. However, further studies are needed to confirm these results and to comprehend the specific interaction between NGAL and VDR pathways in the kidney.

Vitamin D3 Activates Phosphatidylinositol-3-Kinase/Protein Kinase B via Insulin-Like Growth Factor-1 to Improve Testicular Function in Diabetic Rats

OBJECTIVE

In diabetes mellitus, vitamin D₃ deficiency affects sex hormone levels and male fertility; however, the mechanism leading to the disorder is unclear. This research was designed to investigate the mechanism of vitamin D₃ deficiency and hypogonadism in diabetic rats. Our aim was to assess serum vitamin D₃ levels and the relationship among vitamin D₃, insulin-like growth factor-1 (IGF-1), and testicular function.

MATERIALS AND METHODS

Rats with streptozotocin-induced diabetes were randomly divided into four groups and treated with different doses of vitamin D₃: no vitamin D₃, low (0.025 μg/kg/day), high (0.1 μg/kg/day), and high (0.1 μg/kg/day) with JB-1 (the insulin-like growth factor-1 receptor inhibitor group, 100 μg/kg/day). The groups were compared with wild-type rats, which function as the control group. Various parameters such as vitamin D₃ and IGF-1 were compared between the experimental and wild-type groups, and their correlations were determined.

RESULTS

Twelve weeks of vitamin D₃ supplementation improved the testosterone levels, as shown by the increase in the level of serum IGF-1 in diabetic rats. Phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT), which was a downstream of the signaling pathway of IGF-1, was significantly increased after vitamin D₃ treatment.

CONCLUSIONS

The study shows that vitamin D₃ may promote the expression of testosterone and improve testicular function in diabetic rats by activating PI3K/AKT via IGF-1.

Potential Cellular and Biochemical Mechanisms of Exercise and Physical Activity on the Ageing Process

Exercise in young adults has been consistently shown to improve various aspects of physiological and psychological health but we are now realising the potential benefits of exercise with advancing age. Specifically, exercise improves cardiovascular, musculoskeletal, and metabolic health through reductions in oxidative stress, chronic low-grade inflammation and modulating cellular processes within a variety of tissues. In this this chapter we will discuss the effects of acute and chronic exercise on these processes and conditions in an ageing population, and how physical activity affects our vasculature, skeletal muscle function, our immune system, and cardiometabolic risk in older adults.

The Effect of Nordic Walking Training Combined with Vitamin D Supplementation on Postural Control and Muscle Strength in Elderly People-A Randomized Controlled Trial

Nordic Walking (NW) and Vitamin D concentration (Vit D) alone have been shown to contribute to the health and performance of elderly people. However, the interaction between these two factors has yet to be explored. In this study 42 women over 60 years of age (69.02 ± 5.56 years) were recruited and divided in two NW groups: a high-intensity interval training group (HI-NW) and a moderate-intensity continuous training group (MI-NW). Individuals from each group completed a 12-week NW training program (3 times a week/2 hours) combined with randomized Vitamin D supplementation (HD = high dose: 4000 IU/day or LD = low dose: 800 IU/day). Body composition, postural control, muscle strength and Vitamin D serum concentration were measured twice; before and after the intervention. To investigate the interaction between supplementation and training a mixed-design analysis of variance (ANOVA) was performed. The HI-NW group, regardless of supplementation dose, increased their Vit D and elbow torque performance. On the other hand, in the MI-NW group the same Vit D outcome was seen only with HD supplementation and was also associated with increased leg muscle mass. In conclusion, beneficial effects of both HI-NW and MI-NW training regimes were seen. The impact of the dose supplementation on Vit D and body composition was related to the type of NW training.

Exercise and Diabetes: A Narrative Review

Persons with diabetes might experience significant benefits through regular exercise. Not unlike the general population, those with diabetes could also lack motivation to participate in an exercise program. Often, those treating persons with diabetes lack training and/or interest in exercise prescription and are therefore unable to provide the needed information and encouragement. In many cases, reluctance to exercise could result from an inability to find an enjoyable exercise activity. Attempts to find activities that, not only provide effective aerobic challenges, but are also enjoyable to participate in are fraught with difficulty. Three electronic databases were searched in January 2017. Evidence for the merits of exercise for those with diabetes was robust. Numerous reports have addressed the degree of noncompliance to exercise recommendations and the barriers reported for this nonadherence. Additional studies concluded that most medical providers are deficient in formal training in the prescription of an exercise program. Newer studies are evaluating the effects of exercise and vitamin D supplementation and their interplay with diabetic peripheral neuropathy and ulceration. Exercise confers remarkable benefits to those with diabetes; however, the challenges to compelling patients with diabetes to exercise are formidable. An improved focus on exercise prescription and related motivation during provider training must be undertaken.

Treadmill exercise alleviates diabetic cardiomyopathy by suppressing plasminogen activator inhibitor expression and enhancing eNOS in streptozotocin-induced male diabetic rats

OBJECTIVE

To investigate the biological mechanism of the effect of different intensity exercises on diabetic cardiomyopathy.

METHODS

87 raise specific pathogen SPF healthy 6-week-old male Sprague-Dawley rats, fed 6 weeks with high-fat diet for rats were used, and a diabetic model was established by intraperitoneal injection of streptozotocin - randomly selected 43 rats were divided into Diabetic control group (DCG, n = 10), Diabetic exercise group 1 (DEG1, n = 11), Diabetic exercise group 2 (DEG2, n = 11) and Diabetic exercise group 3 (DEG3, n = 11). The rats in DEG1 were forced to run on a motorized treadmill, the exercise load consisted of running at a speed of 10 m/min, the exercise load of the rats in DEG2 were running at a speed of 15 m/min, the exercise load of the rats in DEG3 were running at a speed of 20 m/min, for one hour once a day for 6 weeks. After 6 weeks of exercise intervention, glucose metabolism-related indexes in rats such as blood glucose (FBG), glycosylated serum protein (GSP) and insulin (FINS); cardiac fibrinolytic system parameters such as PAI-1 (plasminogen activator inhibitor 1), Von Willebrand factor (vWF), protein kinase C (PKC) and diacylglycerol (DAG); and serum level of NO, eNOS and T-NOS were measured.

RESULT

Compared with DCG, fasting blood glucose and GSP were decreased, while insulin sensitivity index and insulin level were increased in all rats of the three exercise groups. FBG decrease was statistically significant (P < 0.01), only GSP decrease was statistically significant (P < 0.05) in DEG1 and DEG2, PAI-1 in three exercise groups were significantly reduced (P < 0.05), plasma vWF levels in the three exercise groups were significantly lower than those in the DCG group (P < 0.01); PKC levels decreased dramatically in the three exercise groups and DAG levels decrease slightly (P < 0.05), but with no significant difference. Compared with DCG, the serum level of NO was significantly higher (P < 0.05), and eNOS level was significantly elevated (P < 0.05). T-NOS elevation was statistically significant in DEG1 (P < 0.05).

CONCLUSIONS

Low- and moderate-intensity exercise can better control blood glucose level in diabetic rats; myocardial PAI-1 in DEG1, DEG2 and DEG3 rats decreased significantly (P < 0.05), serum NO increased (P < 0.05) and eNOS increased (P < 0.05) significantly. Therefore, it is inferred that exercise improves the biological mechanism of diabetic cardiomyopathy by affecting the levels of PAI-1 and eNOS, and there is a dependence on intensity.

Reduced Vitamin D Receptor on Circulating Endothelial Progenitor Cells: A New Risk Factor of Coronary Artery Diseases

Aim: Endothelial progenitor cells (EPCs) are shown to participate in the pathological processes of atherosclerosis. While Vitamin D and its receptor axis might exert some effects on EPCs' function. But their exact relationship with clinical patients is still elusive, which inspired us to explore the potential association of vitamin D receptor (VDR) expression on circulating EPCs and serum vitamin D levels among patients with coronary artery disease (CAD).

Methods: Two hundred patients with CAD after their admission to hospital and one hundred healthy controls were enrolled. Medical history data were retrieved and fresh blood samples were collected for flow cytometry analysis. VDR expressions on EPCs were evaluated according to the standardized protocol. Logistic regression analysis was used to investigate the potential risk factor of CAD.

Results: CAD patients were found to have lower log₁₀^VDR-MFIs than those of control group, especially for patients with diabetes (p < 0.001). Log₁₀^VDR-MFIs were inversely correlated with glycated hemoglobin (R = −0.472, p < 0.001), and while EPCs challenged with high glucose had lower VDR expression. Multivariate logistic regression analysis revealed that lower log₁₀^VDR-MFIs were independently associated with the risk of CAD (OR = 0.055, p = 0.008).

Conclusion: A significant decrease of VDR expression on circulating EPCs was observed among CAD patients, particularly among those also with diabetes. VDR expression on EPCs was independently negatively correlated with HbA_1c and high glucose decreased EPCs' VDR expression. Low levels of VDR expression on circulating EPCs might serve as a potential risk factor of CAD.

The Effects of Aerobic Exercises and 25(OH) D Supplementation on GLP1 and DPP4 Level in Type II Diabetic Patients

Background:

The purpose of this study was to investigate the effects of an 8-week aerobic exercise and supplementation of 25(OH)D3 on GLP1 and DDP4 levels in men with type II diabetes.

Methods:

In this semiexperimental research, among 40–60-year-old men with type II diabetes who were referred to the diabetic center of Isabn-E Maryam hospital in Isfahan; of whom, 48 patients were voluntarily accepted and then were randomly divided into 4 groups: aerobic exercise group, aerobic exercise with 25(OH) D supplement group, 25(OH) D supplement group, and the control group. An aerobic exercise program was conducted for 8 weeks (3 sessions/week, each session 60 to75 min with 60–80% HRmax). The supplement user group received 50,000 units of oral Vitamin D once weekly for 8 weeks. The GLP1, DPP4, and 25(OH) D levels were measured before and after the intervention. At last, the data were statistically analyzed using the ANCOVA and post hoc test of least significant difference.

Results:

The results of ANCOVA showed a significant difference between the GLP1 and DPP4 levels in aerobic exercise with control group while these changes were not statistically significant between the 25(OH) D supplement group with control group (P < 0.05).

Conclusions:

Aerobic exercises have resulted an increase in GLP1 level and a decrease in DPP4 level. However, consumption of Vitamin D supplement alone did not cause any changes in GLP1and DPP4 levels but led to an increase in 25-hydroxy Vitamin D level.