Preventive effects of garlic (Allium sativum) on oxidative stress and histopathology of cardiac tissue in streptozotocin-induced diabetic rats

Since some complications of diabetes mellitus may be caused or exacerbated by an oxidative stress, the protective effects of garlic (Allium sativum) were investigated in the blood and heart of streptozotocin-induced diabetic rats. Twenty-eight male Wistar rats were randomly divided into four groups: control, garlic, diabetic, and diabetic+garlic. Diabetes was induced by intraperitoneal (i.p.) injection of streptozotocin (50 mg/kg) in male rats. Rats were fed with raw fresh garlic homogenate (250 mg/kg) six days a week by gavage for a period of 6 weeks. At the end of the 6th week blood samples and heart tissues were collected and used for determination of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and histological evaluation. Induction of diabetes increased MDA levels in blood and homogenates of heart. In diabetic rats treated with garlic, MDA levels decreased in blood and heart homogenates. Treatment of diabetic rats with garlic increased SOD, GPX and CAT in blood and heart homogenates. Histopathological finding of the myocardial tissue confirmed a protective role for garlic in diabetic rats. Thus, the present study reveals that garlic may effectively modulate antioxidants status in the blood and heart of streptozotocin induced-diabetic rats

Modulation of autophagy as the target of mesenchymal stem cells-derived conditioned medium in rat model of myocardial ischemia/reperfusion injury

Human amniotic membrane mesenchymal stem cells-derived conditioned medium (hAM-MSCs-CM) has positive effects against myocardial ischemia/reperfusion (MI/R) injury. However, it needs further investigations how hAM-MSCs-CM leads to the cell survival under MI/R via modulation of autophagy. The purpose of this study is investigating the effects of hAM-MSCs-CM in a rat model of MI/R injury by focusing on the role of autophagy as one of its possible mechanisms. Male Wistar rats (44 rats, 175�200 g) were randomly divided into four groups: Sham, MI/R, culture media-receiving and conditioned medium-receiving. MI/R was induced by 30 min of left anterior descending coronary artery ligation. After 15 min reperfusion, culture media or hAM-MSCs-CM (150 μl) were injected intramyocardially. At the end of the experiment, CK-MB, autophagy markers, phosphorylated and total forms of mTOR and ULK1, cardiac function and fibrosis were measured. hAM-MSCs-CM significantly decreased CK-MB levels (P < 0.0001), and also the mRNA levels of Beclin1 (P < 0.0001), LC3 (P = 0.012) and p62 (P = 0.003). In addition, hAM-MSCs-CM significantly reduced Beclin1, LC3II/LC3I and p62 protein levels (P < 0.0001), and increased p-mTOR/mTOR (P = 0.022) and p-ULK1/ULK1 (P < 0.0001) expressions. Moreover, hAM-MSCs-CM improved cardiac function and decreased fibrosis (P < 0.0001). This study showed cardioprotective effects of hAM-MSCs-CM against MI/R injury through modulation of autophagy via mTOR/ULK1 pathway. Based on these findings, it can be concluded that hAM-MSCs-CM can be offered as an attractive candidate for attenuation of MI/R injury in future, but needs further investigations. © 2021, The Author(s), under exclusive licence to Springer Nature B.V

Diosgenin-induced protection against myocardial ischaemia-reperfusion injury is mediated by mitochondrial K<inf>ATP</inf> channels in a rat model

Objective: This study was aimed to evaluate the effects of diosgenin on myocardial ischaemia-reperfusion injury and the potential involvement of mitochondrial KATP (mitoKATP) channel and nitric oxide (NO) system blockades in this field. Materials and methods: After isolation of hearts of male Wister rats, the study was conducted on control and diosgenin- receiving hearts in the presence or absence of 5-HD and L-NAME (as antagonists of mitoKATP channel and NO system, respectively) in an isolated buffer-perfused heart model. Global ischaemia was induced by 30-min occlusion of aortic flow followed by 90-min reperfusion. Cardiac haemodynamics were recorded throughout the experiment using a PowerLab data acquisition system. Results: The levels of creatine kinase (CK-MB) and lactate dehydrogenase (LDH) in the coronary effluents were estimated colourimetrically. Diosgenin pre-administration significantly decreased the release of LDH and CK-MD into the coronary effluent as compared the with the control group (PATP channels by 5-HD completely eliminated the positive effect of the diosgenin on the LVDP and ±dP/dt (PATP channels. © The Author(s) 2015