Comparison of the preconditioning effect of different exercise training modalities on myocardial ischemia-reperfusion injury.

The study of exercise preconditioning can develop strategies to prevent cardiovascular diseases and outline the efficient exercise model. However, the exercise type with the most protective effect against ischemia-reperfusion injury is unknown. In this study, we examined the effects of three kinds of exercise preconditioning on myocardial ischemia-reperfusion in adult rats and explored the possible underlying mechanisms. Male Wistar rats subjected to ten weeks of endurance, resistance, and concurrent training underwent ischemia (30 min) and reperfusion (120 min) induction. Then, infarction size, serum levels of the CK-MB, the redox status, and angiogenesis proteins (VEGF, ANGP-1, and ANGP-2) were measured in the cardiac tissue. Results showed that different exercise training modes have the same reduction effects on infarction size, but ischemia-reperfusion-induced CK-MB was lower in response to endurance training and concurrent training. Furthermore, cardiac VEGF levels increased in all three kinds of exercise preconditioning but ischemia-reperfusion-induced ANGP-1 elevated more in endurance training. The cardiac GPX activity was improved significantly through the resistance and concurrent exercise compared to the endurance exercise. In addition, all three exercise preconditioning models decreased MPO levels, and ischemia reperfusion-induced MDA was lower in endurance and resistance training. Overall, these results indicated that cardioprotection of exercise training against ischemia-reperfusion injury depends on the exercise modality. Cardioprotective effects of aerobic, resistance, and concurrent exercises are due to different mechanisms. The preconditioning effects of endurance training are mediated mainly by pervasive angiogenic responses and resistance training through oxidative stress amelioration. The preconditioning effects of concurrent training rely on both angiogenesis and oxidative stress amelioration.

Evaluation of protective effects of methylene blue on cisplatin-induced nephrotoxicity.

Cisplatin (CP) is used to treat various types of cancer. However, its usage is limited due to nephrotoxicity. This study aims to examine the applicability of methylene blue (MB) against CP-induced kidney injuries. In this study, twenty-eight male rats were divided into four groups. Following administration of a single dose of CP (5 mg/kg), animals received intraperitoneal injections (IP) of MB (4 mg/kg) for seven days. In the final phase of the experiment, serum was collected from rats, with blood urea nitrogen (BUN) and creatinine (Cr) levels measured. Hematoxylin-Eosin (H&E) and Masson's trichrome staining were performed to examine histological changes. Immuno-histological staining was used to evaluate caspase-3 protein expression. The results showed that the MB (4 mg/kg) + CP treated rats underwent a lesser weight loss compared to the CP group (p < 0.05 and p < 0.001, respectively). The kidney weight decreased significantly in the CP + MB group compared to the CP group (p < 0.05 and p < 001, respectively). BUN and Cr levels that were increased significantly in the serum of the CP group (p < 0.001) compared to the control group showed no significant increase in the MB + CP group compared to the control group (p = 0.842 and p = 0.989, respectively). There was a significant decrease in kidney tissue injuries in the CP + MB compared to the CP group (p < 0.001). The glomerular size was recovered in the CP + MB group compared to the CP (p < 0.05). The significant increase in the capsular space of the CP group compared to the control group (p < 0.001) was attenuated in the CP + MB. MB restored the histological alterations in the kidneys. Treatment with 4 mg/kg of MB reduced the expression levels of Caspase-3. In conclusion, this study provides evidence concerning the anti-apoptotic roles of MB in CP-induced kidney damage. In conclusion, MB has a positive impact on kidney function.

The ameliorative effects of methylene blue on testicular damage induced by cisplatin in rats.

Cisplatin, a common chemotherapeutic drug, can induce testicular toxicity. Methylene blue, a potent antioxidant, can inhibit the generation of free radicals. This research aimed to study the protective effect of methylene blue against the cisplatin-induced toxicity of the reproductive system in rats. 35 male Wistar rats were divided into five groups: the control group, the cisplatin group (a single dose of 5 mg/kg cisplatin), the low-dose and high-dose methylene blue + cisplatin (2 and 4 mg/kg of methylene blue, respectively, for 7 days) and the methylene blue group (4 mg/kg of methylene blue, for 7 days). The treatments were applied through intraperitoneal injection. Cisplatin treatment reduced the sperm parameters and serum testosterone levels significantly. Methylene blue treatment increased the sperm count (p < .001), viability (p < .001) and motility (p < .001) compared to the cisplatin group. The methylene blue group showed a significant increase in the levels of testosterone compared to the cisplatin group (p < .001) and reverted histopathological changes in cisplatin-treated groups. Immunohistochemical evaluation of the caspase-3 protein revealed that the treatment with methylene blue has significant anti-apoptotic effects on testicular tissue damage. In conclusion, methylene blue can attenuate the cisplatin-induced histological damages and improve the sperm parameters.