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Background: Autophagy is a new therapeutic strategy aimed at reducing the diabetic abnormalities. While excessive or insufficient autophagic activity during diabetes leads to altered cellular homeostasis. So, aim of the present study was conducted to determine the effect of eight-week high-intensity interval training (HIIT) along with caffeine injection on the levels of some myocardial autophagy-related proteins in diabetic rats.
Methods: In experimental design, fifty male white wistar rats with an age range of 3-2 months  (average weight 250±25 g) were randomly divided into 5 groups of homogeneous 10 rats in each group: Healthy control (C: intraperitoneal injection of saline), Diabetic control (D: high-fat diet combined with a single intraperitoneal injection of streptozotocin, Diabetic with training (D+T: running with intensity at the 85-90% of maximum speed in 5 to 12 bout of 2 min^-1; 5 days/week for 8 weeks), Diabetic with caffeine supplementation(D+CA: intraperitoneal injection of pure caffeine at 70 mg.kg^-1 5 days/week for 8 weeks), Diabetic with training and with caffeine supplementation (D+T+CA). For evaluate changes in the expression profile of some of the genes associated with autophagy signaling pathway (LC3-II, ULK-1, Beclin1) in the myocardium (left ventricular), based on Western blot analysis will be used. Also, the one-way analysis of variance (ANOVA) and Tukey post hoc test were be used to analyze the data.
Results: The expression of all autophagic proteins in diabetic with trained and non-trained groups was higher than in healthy
group (P≤0.05). On the one hand, the expression of autophagy-related proteins in the trained group with caffeine supplementation was significantly higher than that of the training group without caffeine intake (P=0.001).
Conclusion: The findings of this study suggest that caffeine injection exacerbated the expression of autophagic proteins induced by diabetes; On the other hand, high-intensity interval training can as a preventive strategy, modulate diabetes-induced myocardial autophagy.

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Background: Physical activity plays a major role in the prevention of cardiovascular disease and diabetes, but the effect of intense activity on endoplasmic reticulum proteins and apoptosis and necroptosis in diabetic conditions is unclear. The aim of the present study was to investigate the changes of PERK and CHOP proteins in endoplasmic reticulum of cardiac myocytes of diabetic Wistar rats following continuous and interval exercise.
Methods: For this purpose, 32 male white wistar were purchased and were randomly divided into 4 groups of hemogenus 8 rats in each group: Healthy control (C), Diabetic control (D), Diabetic with moderate-intensity continuous training intensity at the 55min on 26 m/min speed (D+MICT) and Diabetic with high-intensity interval training intensity at the 85-90% of maximum speed (D+HIIT); 5 days/week for 8 weeks. For evaluate changes in the expression of the proteins associated with apoptosis and necroptotic death in the diabetic heart muscle myocardium, based on Western blot analysis will be used. Also, the one-way analysis of variance (ANOVA) is used to determine differences between the study groups.
Results: The results showed that induction of type 2 diabetes increased apoptotic and necroptosis cell death (P≥0.05). Therefore, both continuous and intermittent aerobic exercise modulate apoptotic cell death. And both intermittent and continuous exercise had a significant effect on cell necroptosis death.
Conclusion: It seems that different levels of aerobic exercise have different effects on cardiac myocytes cell death in diabetic rats. But more research is needed to confirm the death of diabetic necroptics.

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Background: Xanthohumol is one of the main bioactive compounds extracted from the female flowers of the hops plant (Humulus lupulus L), that has been shown in several studies to have anti-cancer effects.The MAPK/ERK pathway is one of the key pathways in the regulation of gene expression, cell growth and survival. The abnormal activation of this pathway leads to the uncontrolled cell proliferation in thyroid cancer. This study aims to perform a bioinformatic screening of the proteins in the MAPK/ERK pathway and introduce them as target protein to Xanthohumol. In addition, due to the significant role of EGFR, Grb2, SOS proteins in the MAPK/ERK pathway, they have also been studied.
Method: Using SwissADME software, first the physicochemical, pharmacokinetic and pharmacodynamic characteristics of Xanthohumol are predicted. Then three-dimensional structure of Xanthohumol and target proteins (EGFR, Grb2, SOS, RAS, BRAF, MEK1, MEK2, ERK1, ERK2) were collected from PubChem database and Protein Data Bank, finally, using Auto Dock 4.1.the molecular docking were studied.
Results: Our study shows lack of cytotoxicity in Xanthohumol. In addition, Xanthohumol with proper physicochemical properties does not induce drug resistance through pump P-glycoprotein mechanism. Analysis of molecular docking indicate that Xanthohumol has inhibitory potential to the all proteins studied. Note that its strongest interaction is with MEK2 protein with binding energy-7.04kcal.mol^-1.
Conclusion: According to our results, Xanthohumol has inhibitory potential to the all proteins present in the MAPK/ERK pathway. It lacks cytotoxicity. Thus, it can be considered as an alternative inhibitor for the MAPK/ERK pathway in thyroid cancer cells.

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Background: One of the most important biological pathways involved in maintaining energy homeostasis is the AMPK PGC-1α pathway. Activation of this pathway through exercise can be important in regulating mitochondrial biogenesis processes and maintaining energy balance in diabetics. Therefore, the aim of this study was to investigate the effect of endurance exercise on the content of AMPK and PGC-1α proteins in the left ventricular heart tissue of male rats with type 2 diabetes.

Methods: In this experimental study, 12 two-month-old Sprague-Dawley rats with a mean weight of 270±20 g were selected. After diabetic induction with STZ and Nicotinamide, rats were randomly assigned to two groups, training diabetic and control diabetic (6 heads in group each). The training group performed 4 days a week for 8 weeks, including 30 minutes of endurance training with an intensity of about 50 to 70% of the maximum speed; While the control group did not have any training program. Also, rats did not receive any insulin treatment during the study period. The independent t-test was used in SPSS software version 21 to analyze the data.

Results: A significant increase was observed in the content of AMPK (P=0.002) and PGC-1α (P=0.0001) proteins in the endurance exercise group compared to control.
Conclusion: Based on the results of the present study, endurance exercise was able to significantly increase the content of AMPK and PGC-1α proteins. Therefore, it is possible that an increasing these proteins can lead to energy production and increase mitochondrial biogenesis.

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Background: The relationship between low PGC-1α expression and several metabolic diseases such as diabetes and obesity has been identified. This study investigates the effect of eight-week high intensity interval training (HIIT) and caffeine intake on mitochondrial biogenesis in soleus muscle in diabetic rats induced Streptozotocin.
Methods: In a clinical-interventional animal study, 50 male rats were randomly assigned to 5 equal groups (control group(C), diabetes group(D), diabetes + caffeine group(D+Caf), diabetes + training group(D+T), diabetes + training + caffeine group(D+CAF+T)) and subjected to 8 weeks of caffeine supplementation (70 mg / kg of caffeine powder was injected five days each week) and 8 weeks of 5 sessions per week with 6 to 12 times, 2-min intervals with intensity of 85-90% of maximal speed. Blood was collected directly from the left ventricle to measure blood glucose levels. The soleus muscle of the left leg was extracted and PGC-1α measured by Western Blot method. Independent t-tests, two-way analysis of variance, and Eta squared (p <0.05) were used to analyze the data.
Results: The results showed that induction of diabetes significantly increased blood glucose (P <0.01) and significantly decreased mRNAPGC-1α (P = 0.002). Also, both high-intensity interval training (p = 0.001) and caffeine supplementation (p = 0.03) significantly increased mRNAPGC-1α.
Conclusion: Based on the results of this study, it is possible to suggest the use of HIIT and caffeine consumption as an effective intervention in increasing mitochondrial biogenesis in diabetics. However, a clear statement in this regard requires further research in this area.

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Background: Obesity and type 2 diabetes can impair the function of cells, including CREB and CRTC2 proteins, which are important for regulating adipose tissue metabolism. Therefore, the purpose of the present study was to investigate the effect of eight weeks of high intensity interval training (HIIT) on CREB and CRTC2 proteins levels in subcutaneous adipose tissue of obese rats with type 2 diabetes.

Methods: In this experimental study, 12 head two-month-old Sprague-Dawley rats with a mean weight of 300±20 g were selected. After diabetic induction with Streptozotocin and Nicotinamide, rats were randomly assigned to two groups, diabetic training (6 heads) and diabetic control (6 heads). The training groups performed the training program 4 days a week for 8 weeks, including 5 interval 4-minute with an intensity of 85 to 95% of the maximum speed, and 3-minute active rest periods with an intensity of 50 to 60% of the maximum speed; SPSS software version 23 and independent t-test were used to analyze the data.
Result: After eight weeks of HIIT training, no significant change in CREB protein level was observed in the training group compared to the control (P<0.22); However, a significant increase in CRTC2 protein level was observed in the training group compared to the control (P<0.005);
Conclusion: HIIT training did not result in a change in CREB protein level. But, it was able to increase the CRTC2 protein level, which could lead to the regulation of adipose tissue metabolism in diabetic subjects.

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Background: The pathway of insulin messengers is so important that diabetes can lead to disruption of this pathway. However, the aim of this study was to investigate the effect of 8 weeks of endurance training on protein Kinase-B (PKB or AKT) and mechanical target of rapamycin (mTOR) in the left ventricle of the heart of diabetic rats induced by streptozotocin and nicotinamide.
Methods: In this experimental study, 12 head two-month-old Sprague-Dawley rats with a mean weight of 270±20 g were selected. After diabetic induction with streptozotocin and Nicotinamide, rats were randomly assigned to two groups, training and control (6 heads in group each). The rat training program was performed on a treadmill for 8 weeks and 4 sessions per week, including 30 minutes of endurance training with an intensity of about 50 to 70% of the maximum speed. SPSS software and independent t-test were used to analyze the data.
Results: Eight weeks of endurance training resulted in a significant increase in protein Kinase-B content (P=0.03); But no significant change in Protein Mechanistic Target of Rapamycin content was observed in the endurance training group compared to the control (P=0.97).
Conclusion: protein Kinase-B is a key protein for regulating many cellular pathways, which was significantly increased by eight weeks of endurance training. Due to the fact that the content of protein mechanistic target of rapamycin does not change, it is possible that endurance training cannot lead to physiological hypertrophy heart through the mTORC1 pathway.

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Background: Osteoporosis is one of the most important health problems in the country due to fracture. Osteoporosis Research Center with more than 20 years of experience in this field tries to present achievements and activities of the management and treatment of osteoporosis in the country while introducing this center. This review aims to overview the osteoporosis research center activities on osteoporosis.
Methods: In these conventional review national and international databases were investigated on osteoporosis without any restriction on time and language. Also, other activities that are not reflected in the papers were obtained from the professional website and official reports.
Results: According to the strategic plan of the osteoporosis research center, the achievements of this center provided in in three areas of research (population-based studies, clinical studies, basic science studies and health system studies), technology (diagnostic, therapeutic technologies, service delivery models) and education (training students at different levels of education). Supplementary, patient education, general education, and service provider training).
Conclusion: Osteoporosis Research Center is recognized as the only specialized research center in the field of osteoporosis in the country. The center is trying to improve its position as a regional center in the field of osteoporosis by relying on its strategic and operational plan, in addition to maintaining its current position.
 

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Background: A key aspect of Scientific collaboration increases scientific productivity. This study aimed to draw up a scientific collaboration network of the Endocrinology and Metabolism Research Institute (EMRI) at Tehran University of Medical Sciences.
Methods: A Descriptive Cross-Sectional Study was conducted by the Scientometrics method. Data collection from the Scopus and Web of Science Core collection databases between 2002 until 30 October 2020. MS-Excel, HistCite, VOSviewer, and ScientoPy were used for descriptive statistics and data analysis.
Results: A total of 4190 records with the affiliation of the EMRI are indexed in two international databases. All of the records received a sum of 89480 citations. The EMRI Researchers were published in 1118 journals. The annual growth rate of publication and citation of the scientific output of the EMRI was 20.3% and 22.7%, respectively. A total of 17662 authors from 186 countries participated in the publication. The co-authorship pattern shows. The next section of the Study was classified and visualized based on authorship (institutes and country of affiliation), keywords (co-occurrence and trend).
Conclusion: Overall, these results indicate that the pattern of collaborations in the authorships' articles increases the flow of knowledge among the institute's researchers as a result of international collaborations, interaction with leading countries, and interdisciplinary collaborations. To develop a full picture of co-authorship, additional studies will need a comprehensive picture of network cooperation to analyze the situation with other social network analysis indicators.

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Background: Identifying the risk factors for the health of the elderly and designing interventions to improve the health of the elderly is one of the priorities of the health care system in the world today. This first requires the promotion of scientific knowledge in the field of health problems of the elderly.
Methods: In this review conducted in 1399, all studies with the keyword of aging or age-related diseases such as atherosclerosis, osteoporosis, diabetes, dementia, frailty, cognitive impairment, daily life function, nutritional status with organizational affiliation of the Endocrinology and Metabolism Research center or the Elderly Health Research Center of Tehran University of Medical Sciences were reviewed without time limit in databases, PubMed, Web of Science, Scopus and Google Scalar search engines.
Results: A total of 115 studies were found with these keywords. By examining the sampling, method, data analysis and also the removal of similar data, 63 articles were reviewed.
Conclusion: In this regard, the Elderly Health Research center has conducted several studies to localize tools for assessing the health of the elderly, identifying common diseases of the elderly, the prevalence of diseases and syndromes of the elderly and designing several interventional studies in the form of three large studies Kahrizak elderly study, Bushehr elderly health study and Birjand elderly longitudinal study has been discussed in this review.

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Non-Communicable Diseases (NCDs) are the major cause of premature death and disability due to diseased globally, imposing a heavy burden on the health systems. Four main categories of NCDs are cardiovascular diseases, neoplasms, diabetes, and chronic respiratory diseases. Iran, the second greatest country in the Middle East Region, has been through an important transition period of communicable diseases toward NCDs in the last decades. One of the effective approaches to control NCDs is implementation of population-based studies and interventions, trying to reduce risk factors and incidence of NCDs through investigations in the populations. Endocrinology and Metabolism Research Institute (EMRI) and Non-Communicable Diseases Research Center (NCDRC) are the pioneers trying to study and control various NCDs during the last decades in Iran. In this review, we are going to inspect some of the major completed and ongoing projects of this research institute to highlight valuable efforts to reduce burden of NCDs in Iran, and make a successful example for national and regional public health policy makers and authorities.

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Endocrinology and Metabolism Research Institute (EMRI) was established in 1993. EMRI has progressed step by step from the beginning and has reached maturity in the last 25 years. EMRI has expanded, advanced in human resources and infrastructures (laboratories and new technologies) and gained first rank in endocrine research in various fields. It has also worked with regional and international organizations such as the World Health Organization (WHO), the International Osteoporosis Foundation (IOF), and the American Clinical Endocrine Society (AACE). This article provides an overview of EMRI activities over a quarter of a century.

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Background: Diabetes causes nerve tissue damage and ultimately death of nerve cells, especially in important areas such as the hippocampus. It seems that exercise training and anti-inflammatory supplements can moderate this condition. Therefore, the aim of this study was to determine the effect of aerobic training exercise and L-carnitine consumption on the levels of hippocampus CNTF and CNTFR proteins in diabetic rat.
Methods: 45 Wistar rats between 250 to 300 gr were randomly divided into six groups, including healthy control groups, sham, diabetic control, diabetes + aerobic exercise, diabetes + L-carnitine supplementation and diabetes + aerobic exercise + L-carnitine supplementation. L-carnitine supplements were divided. Diabetic groups underwent subcutaneous injection of 55 mg / kg STZ. supplementary groups received 100 mg of L-carnitine per day orally. The aerobic exercise program was performed for 6 weeks and 5 days a week. The research variables were measured 24 hours after the last training session by the ELISA technics in the hippocampal tissue. The statistical method of one-way analysis of variance and Toki post –hoc test were used to analyze the data.
Results: The present study showed an significant increase in CNTF and CNTFR protein levels of hippocampal tissue after aerobic exercise and L-carnitine consumption (P = 0.001), which greater effect found in combination manner.
Conclusion: Due to the effect of aerobic exercise and L-carnitine supplementation alone and in interaction with each other on hippocampal tissue, the use of this method can be considered as maintaining neural tissue in diabetes.

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Background: The myostatin/SMAD pathway is one of the most important regulatory pathways in heart muscle cells atrophy. Diabetes can disorder this pathway. Therefore, the aim of the present study was to evaluate the effect of six weeks of endurance training on the content myostatin and SMAD2/3 proteins in the left ventricular tissue of the heart muscle of type 1 diabetic rats.
Methods: In this study, 12 head 2-month-old male Sprague-Dawley male rats with a mean weight of 300±20 g were selected. After induction of diabetes through streptozotocin solution, they were randomly divided into 2 groups: diabetic endurance training (6 heads) and diabetic control (6 heads); The training groups performed the training program 4 days a week for 6 weeks, including 32 minutes of endurance training with an intensity of about 50 to 70% of the maximum speed; SPSS software version 23 and independent t-test were used to analyze the data. Significance level was considered p≤0.05.
Findings: Endurance training resulted in a significant decrease in myostatin (P=0.024) and SMAD2/3 (P=0.001) proteins content between training and control groups in myocardial tissue.
Conclusion: It can be said that endurance training by reducing the content of myostatin and SMAD2/3 proteins in the left ventricle of the heart may have been able to prevent cardiac atrophy in type 1 diabetic subjects. This reduction can lead to physiological cardiac hypertrophy.

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Background: The hepatokines are now considered potential targets for the treatment of type 2 diabetes disorders. The aim of this study was to investigate the effect of 12 weeks combined training with Canagliflozin on some hepatokines in type 2 diabetic men.
Methods: In this quasi-experimental study, 44 men with type 2 diabetes (Mean age 33.2 ± 4.5 years, body mass index 27.3±3.0) from Tehran city in 2019 were randomly divided into four groups (n=11) of control, drug, exercise and exercise-drug groups. Combined training was performed 3 sessions per week, 45 minutes for 12 weeks. Subjects were given 200 mg of canagliflozin for 12 weeks. Blood samples and anthropometric characteristics were obtained before and 24 hours after the intervention at 12-hour fasting. Data were analyzed using two-way ANOVA with repeated measures, t-test and Bonferroni post hoc test at P<0.05.
Results: The results showed that 12 weeks of exercise with Canagliflozin intervention significantly reduced angiopoietin-3 and angiopoietin-4, FGF-21 and HFREP-1 levels in type 2 diabetic men (P=0.001). Also, after the intervention of exercise with Canagliflozin, levels of angiopoietin-3, angiopoietin-4, FGF-21, and HFREP-1 were significantly lower than the pre-test (P<0.001).
Conclusion: According to the results of research, it is possible that intervention of exercise with Canagliflozin can help treat of disorders due to type 2 diabetes by reducing hepatokines.

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Background: The formation of islet amyloid polypeptide (IAPP) have been proposed for d increased b-cell apoptosis in type 2 diabetes. Exercise training plays a protective role against diabetes. Alpha lipoic acid (ALA) is a powerful biological antioxidant. However, the role of exercise training and ALA on IAPP are not well understood. The aim of the present study was to investigate the effect of training with different intensity and Alpha lipoic acid supplement on pancreatic mRNA IAPP in rats with type 2 diabetes.
Methods: In this experimental study, 35 wistar rats were randomly divided into seven groups: control, diabetic (D), diabetic+ alpha lipoic acid (ALA), diabetic high intensity training (HIT), diabetic moderate intensity training (MIT), diabetes HIT+ALA (ALA+HIT), diabetic MIT +ALA (ALA+MIT). The HIT and MIT protocols was performed five days a week for six weeks. HIIT included 10 bouts of four minutes (running at 85–90% of VO2max) and MIT 13 bouts of four minutes (running at 65–70% of VO2max). ALA was administered orally 20 mg/kg once a day by gavage. Real-time PCR method for the relative expression of mRNA of IAPP gene were used.
Results: The level of IPAA increased significantly in diabetic group compared to control (p=0.0039). Also, level of IPAA decreased significantly in ALA (p=0.01) and ALA+HIT diabetic group (p=0.021).
Conclusion: diabetes is associated with increased mRNA IAPP in pancreatic b-cell and HIT plus ALA can be as an effective intervention in decreasing IAPP in pancreatic b-cell. in diabetics.

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Background: AMPK and P53 proteins regulate the TOR protein in the TORC1 complex, which regulates many physiological processes. The aim of this study was to evaluate the effect of AMPK and P53 proteins on the TOR pathway following endurance training in the left ventricle of the heart of diabetic rats by streptozotocin and nicotinamide.
Methods: In this experimental study, 12 head two-month-old Sprague-Dawley rats with a mean weight of 270±20 g were selected. After diabetic induction with streptozotocin and Nicotinamide, rats were randomly assigned to two groups, training and control (6 heads in group each). The training group performed endurance training on a treadmill for rodents for 6 weeks and 4 sessions per week for 42 minutes with an intensity of about 50 to 70% of the maximum speed. SPSS software version 23 and independent t-test were used to analyze the data.
Results: Six weeks of endurance training led to significant increase in the protein content of AMPK (P=0.009) and TOR (P=0.005) between training and control groups in the left ventricular tissue of the heart muscle. In contrast, a significant decrease in P53 protein content was observed between the training and control groups in the left ventricular tissue of the heart muscle (P=0.0001).
Conclusion: The results showed that endurance training can with increase the content of AMPK and TOR proteins and decrease the content of P53 protein to regulate processes such as metabolism, mitochondrial biogenesis, cardiac hypertrophy, inhibition of autophagy in the hearts of diabetic subjects.
 

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Background: TORC1 protein is an important factor in regulating adipose tissue metabolism. Type 2 diabetes can lead to dysfunction and the development of obesity. Therefore, the aim of the present study was to investigate the effect of eight weeks of high-intensity interval training (HIIT) and endurance on blood glucose and TORC1 protein content in subcutaneous adipose tissue of obese with type 2 diabetes rats.
Methods: In this study, 18 head 2 Sprague-Dawley male rats with a mean weight of 270±30 g were selected. After becoming type 1 diabetic through streptozotocin and Nicotine amide solution, they were randomly divided into 3 groups: 1) HIIT training 2) endurance training and 3) control (6 heads per group). Exercise groups exercised 4 days a week for 8 weeks according to HIIT and endurance training programs. SPSS software version 23, one-way ANOVA and Tukey post hoc test were used to analyze the data.
Result: Eight weeks of HIIT and endurance training resulted in a significant decrease in blood glucose level (p<0.0001) and a significant increase in TORC1 protein content (P<0.0001) compared to the control group.
Conclusion: HIIT and endurance training lowered blood glucose levels and increase TORC1 protein content, which this training can be a suitable and non-invasive treatment to control diabetes and also regulate adipose tissue metabolism in type 2 diabetics who are prone to obesity.
 

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Background: FOXO family proteins are important factors in autophagy pathway. Protein kinase-B is an important regulator for this family that can be regulated through exercise training. Therefore, the aim of this study is to investigate the effect of protein kinase-B (PKB) on FOXO autophagy family proteins (FOXO1 and FOXO3a) following high intensity interval training (HIIT) in the left ventricle of the heart of diabetic rats by streptozotocin (STZ) and nicotinamide.
Methods: In this experimental study, 12 two-month-old Sprague-Dawley rats with a mean weight of 270±20 g were selected. After type 2 diabetes induction with STZ and Nicotinamide, rats were randomly assigned to two groups, diabetic training (6 heads) and diabetic control (6 heads). The training group trained for 4 days a week in accordance with the training program for 8 weeks. SPSS software version 23 and independent t-test were used to analyze the data. Significance level is considered p≤0.05.
Results: HIIT training resulted in a significant increase in PKB protein content between training and control groups (P=0.0001). In contrast, a significant decrease in protein content of FOXO1 (P=0.003) and FOXO3a (P=0.006) was observed between the training and control groups.
Conclusion: It seems based on the results HIIT with increasing and regulating PKB leads to a decrease and inactivation of FOXO1 and FOXO3a proteins in the hearts of diabetic subjects. Inhibition of these proteins can prevent excessive cardiac autophagy in diabetic subjects.

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Background: Although the relation of serum vitamin D levels with abdominal obesity has been investigated by previous observational studies, the results are inconsistent. In the current study, a dose-response meta-analysis was conducted on epidemiologic studies that evaluated this association in adults.
Methods: We performed a systematic search of all published articles, up to May 2020, in five electronic databases. A total of 41 observational studies that reported odds ratios (ORs) or relative risks (RRs) with 95% confidence intervals (CIs) for abdominal obesity in relation to serum vitamin D levels in adults were found.
Results: Meta-analysis on 36 cross-sectional studies (combining 44 effect sizes) with 257699 participants, illustrated that the highest serum vitamin D level in comparison with the lowest serum vitamin D level was significantly related to 23% decreased odds of central obesity (OR=0.77; 95%CI:0.71-0.83). This inverse association was also significant in almost all subgroups based on different covariates. Based on dose-response analysis, each 25 nmol/l increase in serum vitamin D levels, was related to 8% reduced risk of central obesity (OR=0.92;95%CI:0.85,0.99). After limiting the analysis to 23 effect sizes from 17 studies with representative population (242135 participants), the same results were obtained (OR=0.79; 95%CI: 0.71-0.87). Based on dose-response analysis on studies with representative populations, each 25 nmol/l increase in blood vitamin D levels was linked to 10% decreased central adiposity risk(OR=0.90; 95%CI: 0.82, 0.99).
Conclusion: In this meta-analysis of epidemiologic studies, we demonstrated an inverse significant relation between serum vitamin D levels and risk of central obesity in adults, in a dose-response manner. The same findings were obtained in representative populations.