Diabetic cardiomyopathy in rats was attenuated by endurance exercise through the inhibition of inflammation and apoptosis.

Diabetic cardiomyopathy (DCM), as a ventricular dysfunction, is one of the main causes of death in diabetic patients. Former evidence revealed the beneficial effects of exercise on cardiovascular complications of diabetes. We aimed to investigate the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on DCM. Male Wistar rats were divided into control, diabetic, metformin (300 mg/kg), HIIT, MICT, metformin + HIIT, and metformin + MICT diabetic groups. Serum biochemical, inflammatory, and oxidative stress indicators, gene expression of BCL2 and BAX, and histopathologic changes of cardiac tissue were assessed. Our analysis revealed an increase in fasting blood sugar (FBS), creatine kinase MB (CK-MB), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) in diabetes. Also, the superoxide dismutase (SOD) and catalase (CAT) activity, and the total thiol were decreased, in contrast, malondialdehyde (MDA) levels increased in the cardiac tissue of the diabetic group. All of these changes were significantly ameliorated in diabetic animals treated with exercise and metformin + exercise. The level of tumor necrosis factor-α (TNF-α) and Interleukin-1ß (IL-1ß), as well as the infiltration of inflammatory cells, were decreased in the heart of all exercise training groups. Up-regulation of BCL2 and down-regulation of BAX gene expressions were observed in the cardiac tissue of all exercise-treated groups. In conclusion, HIIT and MICT exercises are effective in preventing DCM development. Exercise training, besides improving oxidative stress and inflammation in cardiac tissue, alleviates cardiac damage by modulating the apoptotic gene expression in diabetic rats.

The effects of endurance exercise and metformin on memory impairment caused by diabetes.

OBJECTIVES: Diabetes has a negative effect on learning and memory performance, and it is a risk factor for Alzheimer's disease and dementia development. The present study aims to investigate the effects of two kinds of endurance exercise including high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) as well as metformin on impaired memory and learning related to streptozotocin (STZ) induced diabetes in rats. METHODS: Forty adult male rats (250 ± 20 g weight) were divided into five groups (n=8), including control, diabetic, as well as diabetic rats treated with metformin (300 mg/kg), and HIIT (20 m/min), and MICT (15 m/min) exercises. Diabetes was induced by STZ (60 mg/kg, i.p.). Serum glucose concentration and oxidative stress markers (SOD, CAT, thiol, and MDA) in the cortex and hippocampus were determined by colorimetric assay. Behavioral tests were performed with a passive avoidance test. RESULTS: The diabetic groups treated with metformin and both HIIT, and MICT exercises improved the latency and the staying time in the darkroom and lightroom. The entrance frequency into the darkroom also was restored (p<0.01-p<0.001). In both HIIT and MICT exercises as well as metformin groups the oxidative stress induced by diabetes has been reversed and attenuation of the serum glucose level has been observed compared to non-treated diabetic ones (p<0.05-p<0.001). CONCLUSIONS: The results of the present study revealed both HIIT and MICT exercises had protective effects against oxidative stress and behavioral impairments induced by diabetes and these effects were comparable to the effects of metformin.

Protective effects of cinnamon on acetylcholinesterase activity and memory dysfunction in diabetic rats.

OBJECTIVES: Regarding neurocognitive and immunomodulatory properties of cinnamon (Cinn) we aimed to investigate whether cinnamon regulates acetylcholinesterase (AChE) activity, and oxidative abnormalities with concomitant memory dysfunction in streptozotocin (STZ)-induced diabetes. METHODS: Forty-seven male adult rats were divided into seven groups (n=8 animals): Control group: in these non-diabetic rats only saline 0.9% NaCl was gavaged, Diabetic (Dia) group: diabetic rats in them saline 0.9% NaCl was gavaged for six weeks. Dia-Cinn 100, Dia-Cinn 200, and Dia-Cinn 400, Dia-Met groups: in these diabetic rats the extract (100, 200, 400 mg/kg respectively) or metformin (300 mg/kg) was gavaged for six weeks. Passive avoidance performance, AChE enzyme activity, and oxidative indicators were examined among the groups. RESULTS: Vs. the control group, blood glucose level and stay time in the dark were remarkably increased in Dia group whereas the latency time was decreased. Meanwhile, antioxidant levels (superoxide dismutase, catalase, and thiols) noticeably decreased in the Dia group compared to the Control group. On the other hand, Cinn extract espicailly at the highest dose recovered the changes similar to those found in the metformin-treated group. CONCLUSIONS: These findings proposed that the cinnamon hydro-ethanolic extract promotes memory recovery in diabetic conditions through the atteuation of the AChE activity and oxidative injury.

PPARγ activation improved learning and memory and attenuated oxidative stress in the hippocampus and cortex of aged rats.

Oxidative stress has an important role in brain aging and its consequences include cognitive decline and physiological disorders. Peroxisome proliferator-activated receptor-γ (PPARγ) activation has been suggested to decrease oxidative stress. In the current research, the effect of PPARγ activation by pioglitazone(Pio) on learning, memory and oxidative stress was evaluated in aged rats. The rats were divided into five groups. In the Control group, vehicle (saline-diluted dimethyl sulfoxide (DMSO)) and saline were injected instead of Pio and scopolamine (Sco), respectively. In the Sco group, the vehicle was injected instead of Pio and the rats were injected by Sco 30 min before the behavioral tests. In the Sco-Pio 10, Sco-Pio 20, and Sco-Pio 30 groups, 10, 20, and 30 mg/kg Pio was injected and finally, the rats were injected with Sco 30 min before the behavioral tests. Morris water mater maze(MWM) and passive avoidance(PA) tests were carried out, and finally, the hippocampus and cortex were removed for biochemical assessments. The results showed that the highest dose of Pio decreased the traveling time and distance during 5 days of learning and increased the time and distance in the target area on the probe day of MWM. The highest dose of Pio also prolonged the delay time for entering the dark and total time spent in the light while decreasing the total time spent in and the number of entries into the dark in PA test. Pio especially, in the medium and highest doses, decreased MDA while increasing thiol, superoxide dismutase, and catalase in the hippocampus and cortex. It is concluded that PPARγ activation by Pio as an agonist improved learning and memory in aged rats probably by attenuating oxidative stress in the hippocampus and cortex.

Anti-inflammatory, anti-oxidant and anti-apoptotic effects of olive leaf extract in cardiac tissue of diabetic rats.

OBJECTIVES: Inflammatory process and apoptosis are involved in the pathogenesis of cardiac injury and oxidative damage caused by diabetes mellitus. The cardioprotective effects of standardized aqueous ethanolic olive leaf extract (OLE), metformin (as a cardiovascular protective agent) and valsartan (as an angiotensin receptor blocker) in the streptozotocin-induced diabetic rats were evaluated. METHODS: Wistar rats divided into control, diabetic, OLE-treated (100, 200 and 400 mg/kg), metformin (300 mg/kg)-treated, valsartan (30 mg/kg)-treated and metformin/valsartan-treated diabetic groups. Biochemical parameters, including malondialdehyde (MDA) levels, superoxide dismutase (SOD) and catalase (CAT) activates, and the total contents of thiol were measured, and histopathological and gene expression studies were done on cardiac tissues. Fasting blood sugar (FBS) and cardiac injury markers were examined in serum. KEY FINDINGS: FBS; the serum levels of lactate dehydrogenase (LDH), creatine kinase-muscle/brain (CK-MB), aspartate aminotransferase (AST); and heart tissue MDA levels due to diabetes were significantly alleviated by OLE treatment (effect size; ηp2 = 0.934, 0.888, 0.848, 0.888 and 0.879, respectively), and SOD and CAT activity and the thiol content in heart tissue were significantly increased (effect size; ηp2 = 0.770, 0.749 and 0.753, respectively). Interleukin-1ß (IL-1ß), tumour necrosis factor-α (TNF-α) and the number of infiltrating inflammatory cells were reduced in cardiac tissues of OLE-treated groups compared with the diabetic rats (effect size; ηp2 = 0.969 and 0.949, respectively). OLE up-regulated BCL2 gene expression and down-regulated BAX gene expression in cardiac tissue (effect size; ηp2= 0.490 and 0.522, respectively). CONCLUSION: OLE in a dose-dependent manner ameliorates cardiac damage in diabetic cardiomyopathy, perhaps through attenuating inflammation, oxidative stress and apoptosis.

A case report of left atrial myxoma presenting with amnesia.

BACKGROUND: Primary cardiac tumors are rare, and approximately 90% of them are benign. Myxoma is the most common type of these tumors occurring in the left atrium in 75-85% of cases. The tumor can cause the left atrio-ventricular valve obstruction and embolization phenomenon. Case presentation We reported a case of 54-year-old man with complaints of dyspenea and amnesia. In our patient, transthoracic echocardiography revealed a mass of 28*63 mm attached to the upper intra-atrial septum, which was prolapsing through the mitral valve into the left ventricle during diastole, being indicative of the left atrial myxoma. On examination, he was alert and conversant, and no pathological abnormality was observed in the examination of cardiovascular, gastrointestinal, respiratory, hepatic, renal and nervous systems. After myxoma diagnosis, the tumor was removed under cardiac surgery and discharged under good conditions. In the telephone follow-up after discharge, the patient recovered and did not report the disease and surgery complications. CONCLUSIONS: Patients with cardiac myxoma are usually asymptomatic, but they may have manifestations related to the embolism phenomenon or intracardiac obstruction. Therefore, myxoma may represent an emergency. Surgery should be performed as soon as possible. If surgery is delayed, the patient may suffer from serious and irreversible complications, such as stroke and cardiac arrest.

Protective effects of medicinal plant against diabetes induced cardiac disorder: A review.

ETHNOPHARMACOLOGY RELEVANCE: Nowadays, there is an increase in global tendency to use medicinal plants as preventive and therapeutic agents to manage diabetes and its long-term complications such as cardiovascular disorders owing to their availability and valuable traditional background. AIM OF STUDY: This review aims to introduce common medicinal plants, which have been demonstrated to have cardioprotective effects on diabetes and their mechanisms of action. MATERIALS AND METHODS: Online literature databases, including Web of Sciences, PubMed, Science Direct, Scopus and Google Scholar were searched without date limitation by May 2020. The following keywords (natural products or medicinal plants or herbal medicine or herb or extract) and (diabetes or antidiabetic or hyperglycemic) and (cardiomyopathy or heart or cardioprotective or cardiac or cardio) were used, and after excluding non-relevant articles, 81 original English articles were selected. RESULTS: The surveyed medicinal plants induced cardioprotective effects mostly through increasing antioxidant effects leading to attenuating ROS production as well as by inhibiting inflammatory signaling pathways and related cytokines. Moreover, they ameliorated the Na+/K + ATPase pump, the L-type Ca2+ channel current, and the intracellular ATP. They also reduced cardiac remodeling and myocardial cell apoptosis through degradation of caspase-3, Bax, P53 protein, enhancement of Bcl-2 protein expression as well as downregulation of TGFß1 and TNFα expression. In addition, the extracts improved cardiac function through increasing EF% and FS% as well as restoring hemodynamic parameters. CONCLUSIONS: The reviewed medicinal plants demonstrated cardioprotective manifestations in diabetes through intervention with mechanisms involved in the diabetic heart to restore cardiovascular complications.