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1. Introduction Diabetic cardiomyopathy (DC) is characterized by ventricular dysfunction, which is not caused by cardiovascular disease and high blood pressure in diabetic patients (Fuentes-Antras et al. 2015). Structural and [...], Diabetic cardiomyopathy (DC) is associated with impaired endoplasmic reticulum (ER) function, development of ER stress, and induction of cardiac cell apoptosis. Preventive effects of BiP inducer X (BIX) were investigated against DC characteristic changes in a type 2 diabetes rat model. To establish diabetes, a high-fat diet and a single dose of streptozotocin were administered. Then, animals were assigned into the following groups: control, BIX, diabetic animals monitored for one, two, and three weeks. Diabetic rats were treated with BIX for one, two, and three weeks. Expressions of various ER stress and apoptotic markers were assessed by immunoblotting method. CHOP gene expression was assessed by Real-time PCR. Tissue expression of BiP was evaluated by immunohistochemistry method. Hematoxylin and eosin and Masson&apos;s trichrome staining were performed to assess histological changes in the left ventricle. Cardiac cell apoptosis was examined using TUNEL assay. BIX administration suppressed the activation of the ER stress markers and cleavage of procaspase-3 in the diabetic rats. Likewise, tissue expression of BiP protein was increased, while CHOP mRNA levels were decreased. These results were accompanied by reducing cardiac fibrosis and myocardial cell apoptosis suggesting protective effects of BIX against the development of DC by decreasing cardiomyocyte apoptosis and fibrosis. Key words: diabetic cardiomyopathy, ER stress, BIX, apoptosis, fibrosis. La cardiomyopathie diabetique (CD) est associee avec l&apos;alteration du fonctionnement du reticulum endoplasmique (RE), l&apos;apparition de stress du RE et la production d&apos;apoptose des cellules cardiaques. Nous avons etudie les effets preventifs du BIX (de l&apos;anglais << BiP inducer X >>) contre les modifications caracteristiques de la CD dans un modele de diabete de type 2 chez le rat. En vue d&apos;obtenir un diabete chez les rats, nous leur avons administre un regime a haute teneur en acides gras et une dose unique de streptozotocine. Puis, nous avons reparti les animaux dans les groupes suivants : temoin, BIX, animaux diabetiques surveilles pendant une, deux ou trois semaines. Les rats diabetiques recevaient du BIX pendant une, deux ou trois semaines. A l&apos;aide de la methode d&apos;immunobuvardage, nous avons evalue l&apos;expression de divers marqueurs du stress du RE et de l&apos;apoptose. A l&apos;aide de la technique de PCR en temps reel, nous avons evalue l&apos;expression du gene CHOP. A l&apos;aide de methodes immunohistochimiques, nous avons evalue l&apos;expression tissulaire du BiP. A l&apos;aide de colorations par l&apos;hematoxyline-eosine et le trichrome de Masson, nous avons evalue les variations histologiques dans le ventricule gauche. A l&apos;aide du test de TUNEL, nous avons examine l&apos;apoptose des cellules cardiaques. L&apos;administration de BIX permettait d&apos;inhiber completement l&apos;activation des marqueurs du stress du RE et le clivage de la procaspase-3 chez les rats diabetiques. Egalement, nous avons observe une augmentation de l&apos;expression tissulaire de la proteine BiP, avec une diminution des taux d&apos;ARNm du gene CHOP. Ces resultats s&apos;accompagnaient d&apos;une attenuation de la fibrose cardiaque et de l&apos;apoptose des cellules myocardiques, ce qui laissait entrevoir la presence d&apos;effets protecteurs du BIX contre la survenue de la CD, par l&apos;intermediaire de l&apos;attenuation de l&apos;apoptose des cardiomyocytes et de la fibrose. [Traduit par la Redaction] Mots-cles : cardiomyopathie diabetique, stress du reticulum endoplasmique, BIX, apoptose, fibrose. more...

Objective: Angiogenesis can be influenced by many factors. The main purpose of the present study was to explore the effect of aerobic training and intermittent hypoxia on angiogenic factors in the cardiac tissue of male Wistar rats. Methods: Thirty male Wistar rats were randomly divided into one of three groups; normal control (NC), hypoxia (H), and training (T). The Hypoxia group was exposed to chronic periodic and isobaric hypoxia (total pressure PiO2~760 mmHg, 14% oxygen) for 8 weeks. Animals in the training group ran on a motorized treadmill (22-26 meters per min) for 8 weeks, 5 sessions per week. At the end of the procedure, protein expression of Tie-1, HIF-1a, VEGF, and P-AKT were calculated by an immunoblotting technique in the cardiac tissue. Results: The findings indicated that periodic hypoxia and exercise training substantially raised the expression of the HIF-1a, VEGF, and P-AKT proteins as compared to the NC (p = 0.001). Moreover, chronic treadmill training significantly increased the phosphorylation of AKT as compared to the hypoxia group (p = 0.001), indicating that PI3K/Akt signalling pathway is influenced by exercise training rather than hypoxia. Conclusion: It seems that both hypoxia and exercise training are potent stimulators for the induction of angiogenesis signalling pathway. [ABSTRACT FROM AUTHOR] more...

Previous studies have noted that the incidence of inflammatory and fibrotic diseases is higher in diabetic menopausal women. In the present study, we evaluated effects of swimming training on inflammatory and fibrotic biomarkers in the lung of ovariectomized diabetic rats. Forty female rats were assigned into four groups: sham; rats underwent surgery without ovariectomies, OVX: rats that underwent ovariectomies, OVX.Dia: ovariectomized rats with high-fat diet, OVX.Dia. Exe: ovariectomized diabetic rats with 8 weeks of swimming training. At the end of experiment, protein expressions were assessed with western blot. Lung sections were subjected to immunohistochemical and haematoxylin eosin staining. There was a significant difference in the protein expressions between exercise and ovariectomized diabetic groups (p <.05). The present study showed strong potential of swimming training on oestrogen deficient diabetic lung. These data encourage further investigation into the inclusive effects of exercise in menopausal diabetic women. [ABSTRACT FROM AUTHOR] more...

Fibroblast growth factor 21 (FGF-21) and myostatin have been proposed to be potential therapeutic target for insulin resistance in age-related metabolic disorders including type 2 diabetes (T2D). Moreover, despite the potential metabolic effect of resistance training on insulin resistance, aging, and T2D; the effect of this type of exercise training on FGF-21 and myostatin in elderly men with and without T2D are unknown. Forty-four elderly men were assigned to either the RT training (RT; without T2D: 12, with TD2 = 10) or the control group (C; without T2D: 12, with TD2 = 10). The RT group performed 12-wk resistance training intervention, 3 days/wk, 10 repetitions with 70% 1RM. At the baseline, the elderly men with T2D had a higher FGF-21 (p = 0.002) and myostatin (p = 0.02) concentrations and lower muscle strength (p = 0.01) than the elderly men without T2D. RT resulted in significant decrease in FGF-21 and myostatin concentration and increase in muscle strength in both elderly men with and without T2D (P = 0.001, for all) as well as decrease in HOMA-IR in only elderly men without T2D (P = 0.001). There was no significant difference in the RT-induced FGF-21 reduction between elderly men with and without T2D (p = 0.77, p = 0.28, respectively), but, RT caused a larger reduction in circulating myostatin in elderly men without T2D than with T2D (P = 0.007). Taken together, our results demonstrated that 12 weeks of RT induced an overall significant reduction of FGF-21 and myostatin in elderly men with and without T2D; with higher reduction of myostatin in elderly men without T2D. [ABSTRACT FROM AUTHOR] more...

Copyright of Medical Journal of Tabriz University of Medical Sciences is the property of Tabriz University of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Copyright of Medical Journal of Tabriz University of Medical Sciences is the property of Tabriz University of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Introduction: Overexposure to heat conditions can affect the functioning of the cardiovascular system and may promote cardiovascular disorders. Heat shock induced myocardial injury via increasing endoplasmic reticulum response-mediated apoptosis. This study investigated the impact of pretreatment with Rosa canina (RC), a natural antioxidant, on myocardial damage induced by heat stress exposure and underlying mechanisms in cardiomyocytes in rats. Methods: Sixty adult male Wistar rats were allocated into five groups, including Control: received normal saline (NS), Heat Stress (HS), and HS+RC groups. Animals in the HS groups were subjected to heat stress (43 ºC) for 15 minutes once a day for two weeks. Animals in the HS+RC groups received three doses of RC (250, 500, and 1000 mg/mL) one hour before being subjected to heat shock. The endoplasmic reticulum (ER) transmembrane kinases, including PKR-like endoplasmic reticulum kinase (PERK), immunoreactivity of CCAAT/enhancer-binding protein homologous protein (CHOP), and eukaryotic translation initiation factor 2-alpha (eIF2α) as well as caspase 8 were detected by Western blot. The levels of reactive oxygen species (ROS) were assessed. Moreover, histopathological changes and apoptosis were also assayed in the heart tissue by using histopathological and TUNEL assays. Results: Heat exposure increased the level of ROS and induced oxidative damage in the heart tissue. The results demonstrated that RC administration decreased the overproduction of ROS induced by heat stress in cardiomyocytes. Moreover, heat stress upregulated the expression of p-PERK, p-eIF2α, and CHOP protein while pretreatment with RC decreased expression of ER stress-related markers in cardiomyocytes. Besides, RC diminished heat stress-induced cellular damage and apoptosis associated with inhibition of caspase 8 activation, a pro-apoptotic protein in cardiomyocytes. Conclusion: These findings indicate that RC exerts a protective effect on heart tissue, at least in part, through inactivation of PERK/eIF2α/CHOP pathway or inhibition of ER stress and oxidative stresstriggered apoptosis in cardiomyocytes induced by heat stress. [ABSTRACT FROM AUTHOR] more...

Background and Aim Apoptosis or programmed death is active biological process and reversible that the balance between growth and cell death in various tissues, particularly myocardial tissue is essential role. The aim of this study was the effect of 8 weeks High Intensity Interval Training (HIIT) with and without food restriction on gene expression of Caspase 3 and 9 in rats. Methods & Materials This study was experimental multi group design with control group which conducted on 30 rats with two months old male. Subjects were divided in to five homogenous groups including base control, control, caloric restriction, interval exercise training and caloric restriction+interval exercise training. Training groups five sessions in weeks were participated in interval exercise training for 8 weeks. The level of gene expression of the proteins Caspase 3 and 9 was evaluated by Real Time-PCR. Dates were analyzed using the 1-way ANOVA at the level of (P<0.05). Ethical Considerations The protocol of this study was approved by the Medical Committee of Sanandaj University of Medical Sciences (Code: IR.MYK.REC.1397.5022). Results The results showed that the training group had a significant decrease in gene expression of Caspase 3 in comparison with caloric restriction+exercise training (P<0.05). Also, exercise training and exercise training+caloric restriction significantly decrease in the gene expression of Caspase 9 compared to caloric restriction, base control and control (P<0.05) and significantly decrease in the gene expression of Caspase 3 compared to base control and control (P<0.05). Conclusion According to the results, it seems that high intensity interval training with and without calorie restriction provides the necessary adaptations to inhibit or stop apoptosis induced by aerobic exercise. [ABSTRACT FROM AUTHOR] more...

Background: Despite the effect of PGC-1α on biogenesis of mitochondria, the mechanism of its effect on cardiac angiogenesis has not yet been studied. Therefore, the purpose of this study was to investigate the effect of aerobic training and intermittent hypoxia on the expression of PGC-1α angiogenesis-related proteins in the cardiac tissue. Methods: In an experimental study, Forty male Wistar rats weighing 220±20 gr were randomly divided into four groups; control (C), hypoxia (H), training (T), and Hypoxia + training (H+T) groups. Hypoxia group exposed to chronic intermittent hypoxia (PiO2≈106 mmHg, simulated altitude ≈ 3400 m, 14% oxygen for 8 weeks). And exercise group ran on a treadmill for 8 weeks, 5 session/ week. Then, relative protein density of PGC-1α, p-AMPK, ERRα, and VEGFA were measured with Western blot method. Results: The aerobic training, intermittent hypoxia, aerobic training + hypoxia significantly increased relative protein density of PGC-1α, ERRα, and VEGFA compared to control group. Moreover, phosphorylation levels of AMPK showed an increase in all three groups compared to the control group. Conclusion: Although hypoxia was an effective stimulator to induce the expression of PGC-1α and VEGFA and aerobic exercise was a potent phosphorylation inducer of AMPK, their combination did not have a synergistic effect. [ABSTRACT FROM AUTHOR] more...