Ischemia-reperfusion Group Research Articles

Nicotinamide mononucleotide and melatonin counteract myocardial ischemia-reperfusion injury by activating SIRT3/FOXO1 and reducing apoptosis in aged male rats.

It has been documented that aging increases the risk of cardiovascular disease including myocardial ischemia/reperfusion (IR) injury and acute myocardial infarction. In this study, we aimed to investigate the individual or combined effects of nicotinamide mononucleotide (NMN) and melatonin (Mel) treatment on apoptotic markers, expression of SIRT3, and FOXO1, and infarct size of the aged myocardium subjected to IR injury. Sixty aged Wistar rats (22-24months) were assigned to five groups including sham, IR, NMN+IR, Mel+IR, and NMN+Mel+IR (combination therapy). Isolated hearts were exposed to 30-min regional ischemia followed by 60-min reperfusion. NMN (100mg/kg/day/i.p.) was injected every second day starting on day 28 before IR injury. Melatonin was added to the perfusion solution five minutes prior to and until 15min after the start of reperfusion. The infarct size was assessed by computerized planimetry. The mRNA levels of SIRT3, FOXO1, and apoptotic genes Bax, Bcl-2, and Caspase-3 were estimated by real-time PCR. All treatments reduced infarct size as compared with the IR group. Melatonin and NMN upregulated the gene expression of Bcl-2, SIRT3, and FOXO1 and downregulated the gene expression of Bax, and Caspase-3, in comparison to the IR group. Also, the protein levels of SIRT3, quantified by Western blotting, were upregulated by the interventions. The effects of combination therapy were significantly greater than those of melatonin or NMN alone. These findings indicate that the combined administration of NMN and melatonin can protect the aged heart against IR injury by decreasing apoptosis and activating the SIRT3/FOXO1 pathway.

Salt-inducible kinase 2 regulates energy metabolism in rats with cerebral ischemia-reperfusion.

To investigate the effects of salt-inducible kinase 2 (SIK2) on energy metabolism in rats with cerebral ischemia-reperfusion. Adult SD male rats were divided into 5 groups: sham group, ischemia group, reperfusion group, adenovirus no-load group, and SIK2 overexpression group with 5 animals in each group. The middle cerebral artery occlusion (MCAO) was induced with the modified Zea-Longa line thrombus method to establish the cerebral ischemia reperfusion model. Eight days before the MCAO, SIK2 overexpression was induced by injecting 7 μL adenovirus in the right ventricle, then MCAO was performed for followed by reperfusion HE staining was used to observe the pathological changes of cerebral tissue in rats; TTC staining was used to observe the volume of cerebral infarct. The levels of adenosine triphosphate (ATP) and adenosine diphosphate (ADP) in rat brain tissue were detected by ELISA; the levels of SIK2 and hypoxia-inducible factor 1α (HIF-1α) in the rat brain tissues were detected by RT-qPCR and Western blotting. Compared with the sham group, SIK2 level was decreased in the ischemia group, and it was further declined in the reperfusion group (<0.05). Compared with the sham group and ischemic group, the pathological injury in reperfusion group were more severe, and the infarct size was larger; compared with the reperfusion group and adenovirus no-load group, the pathological injury of the SIK2 overexpression group was milder, and the infarct size is less. Compared with the sharn group, HIF-1α was increased in both ischemia group and reperfusion group, especially in ischemia group (all <0.05); HIF-1α level in the SIK2 overexpression group was higher than that in the reperfusion group and adenovirus no-load group (all <0.05). ATP level in ischemia group and reperfusion group was lower than that in the sham group, and the reperfusion group decreased more significantly than the ischemia group (<0.05); ADP content was increased in the ischemia and reperfusion group, and the ADP content in reperfusion group was significantly higher than that in the ischemia group (<0.05). ATP level in the SIK2 overexpression group was higher than that in the reperfusion group and adenovirus no-load group (all <0.05), and ADP was decreased in the SIK2 overexpression group (all <0.05). SIK2 can up-regulate the ATP level and down-regulate the ADP level in rat brain tissue and alleviate cerebral ischemia-reperfusion injury by increase the level of HIF-1α.

LDH and PDH Activities in the Ischemic Brain and the Effect of Reperfusion-An Ex Vivo MR Study in Rat Brain Slices Using Hyperpolarized [1-13C]Pyruvate.

Ischemic stroke is a leading cause for neurologic disability worldwide, for which reperfusion is the only available treatment. Neuroimaging in stroke guides treatment, and therefore determines the clinical outcome. However, there are currently no imaging biomarkers for the status of the ischemic brain tissue. Such biomarkers could potentially be useful for guiding treatment in patients presenting with ischemic stroke. Hyperpolarized 13C MR of [1-13C]pyruvate is a clinically translatable method used to characterize tissue metabolism non-invasively in a relevant timescale. The aim of this study was to utilize hyperpolarized [1-13C]pyruvate to investigate the metabolic consequences of an ischemic insult immediately during reperfusion and upon recovery of the brain tissue. The rates of lactate dehydrogenase (LDH) and pyruvate dehydrogenase (PDH) were quantified by monitoring the rates of [1-13C]lactate and [13C]bicarbonate production from hyperpolarized [1-13C]pyruvate. 31P NMR of the perfused brain slices showed that this system is suitable for studying ischemia and recovery following reperfusion. This was indicated by the levels of the high-energy phosphates (tissue viability) and the chemical shift of the inorganic phosphate signal (tissue pH). Acidification, which was observed during the ischemic insult, has returned to baseline level following reperfusion. The LDH/PDH activity ratio increased following ischemia, from 47.0 ± 12.7 in the control group (n = 6) to 217.4 ± 121.3 in the ischemia-reperfusion group (n = 6). Following the recovery period (ca. 1.5 h), this value had returned to its pre-ischemia (baseline) level, suggesting the LDH/PDH enzyme activity ratio may be used as a potential indicator for the status of the ischemic and recovering brain.

Intravoxel Incoherent Motion and Dynamic Contrast-Enhanced Magnetic Resonance Imaging to Early Detect Tissue Injury and Microcirculation Alteration in Hepatic Injury Induced by Intestinal Ischemia-Reperfusion in a Rat Model.

BackgroundIntravoxel incoherent motion (IVIM) can provide quantitative information about water diffusion and perfusion that can be used to evaluate hepatic injury, but it has not been studied in hepatic injury induced by intestinal ischemia–reperfusion (IIR). Dynamic contrast‐enhanced (DCE) magnetic resonance imaging (MRI) can provide perfusion data, but it is unclear whether it can provide useful information for assessing hepatic injury induced by IIR.PurposeTo examine whether IVIM and DCE‐MRI can detect early IIR‐induced hepatic changes, and to evaluate the relationship between IVIM and DCE‐derived parameters and biochemical indicators and histological scores.Study TypeProspective pre‐clinical study.PopulationForty‐two male Sprague–Dawley rats.Field Strength/SequenceIVIM‐diffusion‐weighted imaging (DWI) using diffusion‐weighted echo‐planar imaging sequence and DCE‐MRI using fast spoiled gradient recalled‐based sequence at 3.0 T.AssessmentAll rats were randomly divided into the control group (Sham), the simple ischemia group, the ischemia–reperfusion (IR) group (IR1h, IR2h, IR3h, and IR4h) in a model of secondary hepatic injury caused by IIR, and IIR was induced by clamping the superior mesenteric artery for 60 minutes and then removing the vascular clamp. Advanced Workstation (AW) 4.6 was used to calculate the imaging parameters (apparent diffusion coefficient [ADC], true diffusion coefficient [D], perfusion‐related diffusion [D *] and volume fraction [f]) of IVIM. OmniKinetics (OK) software was used to calculate the DCE imaging parameters (K trans, K ep, and V e). Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were analyzed with an automatic biochemical analyzer. Superoxide dismutase (SOD) activity was assessed using the nitro‐blue tetrazolium method. Malondialdehyde (MDA) was determined by thiobarbituric acid colorimetry. Histopathology was performed with hematoxylin and eosin staining.Statistical TestsOne‐way analysis of variance (ANOVA) and Bonferroni post‐hoc tests were used to analyze the imaging parameters and biochemical indicators among the different groups. Pearson correlation analysis was applied to determine the correlation between imaging parameters and biochemical indicators or histological score.ResultsALT and MDA reached peak levels at IR4h, while SOD reached the minimum level at IR4h (all P < 0.05). ADC, D, D *, and f gradually decreased as reperfusion continued, and K trans and V e gradually increased (all P < 0.05). The degrees of change for f and V e were greater than those of other imaging parameters at IR1h (all P < 0.05). All groups showed good correlation between imaging parameters and SOD and MDA (r[ADC] = 0.615, −0.666, r[D] = 0.493, −0.612, r[D *] = 0.607, −0.647, r[f] = 0.637, −0.682, r[K trans] = −0.522, 0.500, r[V e] = −0.590, 0.665, respectively; all P < 0.05). However, the IR groups showed poor or no correlation between the imaging parameters and SOD and MDA (P [K trans and MDA] = 0.050, P [D and SOD] = 0.125, P [the remaining imaging parameters] < 0.05). All groups showed a positive correlation between histological score and K trans and V e (r = 0.775, 0.874, all P < 0.05), and a negative correlation between histological score and ADC, D, f, and D * (r = −0.739, −0.821, −0.868, −0.841, respectively; all P < 0.05). For the IR groups, there was a positive correlation between histological score and K trans and V e (r = 0.747, 0.802, all P < 0.05), and a negative correlation between histological score and ADC, D, f, and D * (r = −0.567, −0.712, −0.715, −0.779, respectively; all P < 0.05).Data ConclusionThe combined application of IVIM and DCE‐MRI has the potential to be used as an imaging tool for monitoring IIR‐induced hepatic histopathology.Level of Evidence1Technical Efficacy Stage2

Anti-HMGB1 Monoclonal Antibody Ameliorates Lung Ischemia Reperfusion Injury in Mice

Purpose Lung ischemia reperfusion (IR) injury increases the mortality and morbidity in patients undergoing lung transplantation. Inflammatory mediators called Damage Associated Molecular Patterns (DAMPs) concern with inflammatory response to develop the organ damages during IR injury and High Mobility Group Box 1 (HMGB1) is one of the most important DAMPs. We had previously developed anti-HMGB1 monoclonal antibody (mAb) and assessed the therapeutic effect of the antibody in lung IR injury. Methods A mice hilar clamp model of IR was used, and animals were divided into sham groups and IR groups with or without administration of anti-HMGB 1 mAb. We analyzed the effect of anti-HMGB 1 mAb against IR injury by assessing lung oxygenation, injury, neutrophil infiltrations, expression of proinflammatory cytokines and chemokines, MAPK signaling and apoptosis. Results The severity of IR injury represented by oxygenation capacity, lung injury score and neutrophil infiltrations was significantly improved by anti-HMGB1 mAb treatment. The expressions of proinflammatory factors including IL-1b, IL-6, IL-12, TNFα, CXCL1 and CXCL2 and phosphorylation of p38 MAPK were significantly reduced by the anti-HMGB1 mAb treatment. Furthermore, the antibody decreased TUNEL positive cells to detect apoptosis. Conclusion Anti-HMGB1 mAb obviously ameliorated lung IR injury by reduction of inflammatory responses and apoptosis. Our findings indicate that anti-HMGB1 mAb have a potential as therapeutic drug to improve IR injury in lung transplantation.

Alteration of connexins gene expression by silibinin during hepatic warm ischemia-reperfusion injury in the rat model

Background: Ischemia-reperfusion injury (IRI) is an injurious phenomenon that is the primary determinant of liver dysfunction after surgery and transplantation. The present evidence demonstrated that connexin 43 (Cx43), Cx32, and Cx26 are the essential gap junction proteins involved in the liver IRI. This study aimed to characterize the beneficial effects of silibinin on Cx43, Cx32, and Cx26 gene expression during warm hepatic ischemia-reperfusion (IR). Materials and Methods: A total of 32 male Wistar rats weighing 250-300 g were randomly divided into four equal groups of eight animals in each group as follows: 1) control group (laparotomy+normal saline), 2) laparotomy+silibinin (30 mg/kg) (SILI), 3) liver IR procedure+normal saline (IR), and 4) liver IR procedure+silibinin (30 mg/kg) (IR+SILI). After 1 h of ischemia followed by 3 h of reperfusion, blood samples and tissue sections were gathered to assess the serum liver markers and evaluate the liver histological changes as well as gene expression, respectively. Results: The obtained data proved no considerable differences between control and SILI groups in all experiments. Furthermore, the gene expression of Cx26, Cx32, and Cx43 was significantly induced in the IR group, compared to the control group. Silibinin markedly reduced Cx26 and Cx32 mRNA expression, whereas increased Cx43 mRNA expression. Moreover, serum alanine aminotransferase and aspartate aminotransferase levels were markedly elevated in the IR group (P&lt;0.001), compared to the control group. However, in the IR+SILI group, silibinin could significantly decline these elevations, compared to the IR group. In addition, silibinin diminished hepatic tissue damages during IR. Conclusion: Silibinin could attenuate liver injury through better cell-to-cell communication via lowering Cx32 and Cx26, as well as increasing Cx43 gene expression, respectively.

Zinc is a strong stimulant of metallothionein synthesis in the ischaemic testis tissue.

This study was performed to determine the effect of zinc supplementation effects on metallothionein levels in testis ischaemia-reperfusion of rats. The experimental groups were designed as Control, Sham, Ischaemia-Reperfusion (I/R) and I/R+Zinc supplemented. Zinc supplemented as 5mg/kg day for 3weeks. Testis tissues were analysed for metallothionein by immunohistochemical staining procedures. Group comparison showed that the zinc-supplemented ischaemia-reperfusion group had a significantly higher level of cells strongly stained with metallothionein than all other groups. A general evaluation of the results suggests that zinc supplementation is a strong stimulant of metallothionein synthesis in the ischaemic testis tissue.

The Protective Role of Bmal1-Regulated Autophagy Mediated by HDAC3/SIRT1 Pathway in Myocardial Ischemia/Reperfusion Injury of Diabetic Rats

Histone deacetylase 3 (HDAC3) and silent information regulator 1 (SIRT1) are histone deacetylases that regulate important metabolic pathways and play important roles in diabetes and myocardial ischemia/reperfusion (IR) injury. In this study, we explored the protective mechanism of Bmal1-regulated autophagy mediated by the HDAC3/SIRT1 pathway in myocardial IR injury of diabetic rats. Type 1 diabetes was established by administering an intraperitoneal injection of streptozotocin. After 8 weeks, the left anterior descending coronary artery was ligated for 30 min and reperfused for 120 min to establish a myocardial IR injury model in diabetic rats. H9c2 cardiomyocytes were exposed to high glucose concentration (30 mM) and hypoxia/reoxygenation (H/R) stimulation in vitro. The myocardial infarct size and levels of serum cTn-I, CK-MB, and LDH in diabetic rats subjected to myocardial IR injury were significantly higher. Upregulated HDAC3 and downregulated SIRT1 expression were observed in diabetic and IR hearts, along with a lower Bmal1 level. Autophagy was rapidly increased in the hearts of diabetic or non-diabetic rats in the IR group compared with the sham group, but significantly attenuated in the hearts of diabetic rats compared with the hearts of non-diabetic rats after IR insult. Consistent with decreased autophagy, we observed increased HDAC3 expression and decreased SIRT1 and Bmal1 levels in the myocardial tissue of diabetic rats after IR. Inhibition of HDAC3 by the inhibitor RGFP966 and activation of SIRT1 by the agonist SRT1720 could significantly attenuate myocardial IR injury in diabetic rats by restoring Bmal1-regulated autophagy. Based on these findings, the disordered HDAC3/SIRT1 circuit (upregulated HDAC3 and downregulated SIRT1 levels) plays an important role in aggravating myocardial IR injury in diabetic rats by downregulating Bmal1-mediated autophagy. Treatments targeting HDAC3/SIRT1 to activate the autophagy may represent a novel strategy to alleviate myocardial IR injury in diabetes.

Protective effect of liraglutide on experimental testicular ischaemia reperfusion in rats.

This study was performed to evaluate the effect of liraglutide on experimental testicular ischaemia reperfusion in rats in terms of biochemistry, histopathology and immunohistochemistry. A total of 28 male Wistar-Albino rats were divided randomly into 4 groups: control (7), sham (7), ischaemia-reperfusion (7) and ischaemia-reperfusion + liraglutide (7). Biochemically, Nitric Oxide, Malondialdehyde, Superoxide dismutase, Glutathione peroxidase and Catalase levels were measured in the testis. Apoptosis protease activating factor-1 and inducible nitric oxide synthase activity were evaluated immunohistochemically as well. Statistical analyses were made via the Kruskal-Wallis and Mann-Whitney U tests. In the reperfusion group, CAT and SOD values were increased (p>.05), NO and MDA values were decreased (p<.05) after administration of liraglutide. In addition, GPx values were significantly increased in ischaemia reperfusion + liraglutide administered group compared to reperfusion group (p<.05). Apaf-1 and iNOS activity were significantly decreased with the addition of liraglutide treatment to the ischaemia-reperfusion group (p<.05). First of all, we would like to say that liraglutide treatment is moderately preventive against I/R injury in testicular torsion. The anti-inflammatory, antioxidant and antiapoptotic properties of liraglutide are create a moderately protective effect as we show in this study.

Effect of Quercetin-Loaded Mesoporous Silica Nanoparticles on Myocardial Ischemia-Reperfusion Injury in Rats and Its Mechanism.

BackgroundQuercetin has potential value in treating cardiovascular diseases, but it is not suitable for clinical application due to its own water solubility. The limitation of quercetin can be distinctly ameliorated by delivering it with nanocarriers.ObjectiveTo determine the effect of quercetin-loaded mesoporous silica nanoparticles (Q-MSNs) on myocardial ischemia-reperfusion injury in rats and its mechanism.MethodsQ-MSNs were synthesized, and the morphology of Q-MSNs and MSNs was characterized by transmission electron microscopy and dynamic light scattering technique, respectively. Healthy rats were enrolled and randomly divided into a sham operation control group, an ischemia-reperfusion (IR) group, an IR+Q group, an IR+Q-MSNs group, and an MSNs group (each n = 10). Rats in the sham operation group were not treated with ischemia reperfusion, but given normal perfusion meantime. Rats in the sham operation control group, IR group, and MSNs group were given normal saline for 10 days before ischemia reperfusion, and rats in the IR+Q group and IR+Q-MSNs group were given drugs by gavage for 10 days before ischemia reperfusion. Primary myocardial cells were sampled from SD neonatal rats to construct hypoxia/reoxygenation myocardial cell models. The myocardial cells were assigned to a control group, IR group, quercetin (Q) group, Q-MSNs group, and MSNs group. Except for the control group, all the other groups were treated with hypoxia/reoxygenation. Cells in the Q group were treated with quercetin (10 μM, 20 μM, 40 μM) for 24 h in advance and then treated with measures to cause hypoxia-reoxygenation injury. Cells in the Q-MSNs group were treated with the same concentration of loaded quercetin and the same method used for the Q group. The myocardial apoptosis, myocardial infarction, ventricular remodeling, hemodynamic indexes, physiological and biochemical indexes, and JAK2/STAT3 pathway expression of each group were detected, and the apoptosis, viability, oxidative stress, and JAK2/STAT3 pathway expression of primary myocardial cells in each group were also detected.ResultsQuercetin significantly activated the JAK2/STAT3 pathway in vivo and in vitro, and MSNs intensified the activation. Compared with quercetin, Q-MSNs were more effective in inhibiting cell apoptosis and oxidative stress, reducing myocardial infarction size, improving ventricular remodeling and cardiac function-related biochemical indexes, and promoting the recovery of cardiac blood flow.ConclusionQ-MSNs can significantly enhance the activation effect of quercetin on JAK2/STAT3 pathway, thus enhancing its protection on the heart of MIRI rats.

Comparison of remote and local postconditioning against hepatic ischemic-reperfusion injury in rats.

ABSTRACTPurpose:The aim of this study is to compare the hepatic protective effect of both remote and local postconditioning (POS).Methods:Twenty-eight Wistar rats were assigned into four groups: sham group(SHAM), ischemia-reperfusion group (IR), local ischemic POS group (lPOS) and remote ischemic POS group (rPOS). Animals were subjected to liver ischemia for 30 min. Local ischemic POS group consisted of four cycles of 5 min liver ischemia, followed by 5 min reperfusion (40 min). Remote ischemic POS group consisted of four cycles of 5 min hind limb ischemia, followed by 5 min hind limb perfusion after the main liver ischemia period. After 190 minutes median and left liver lobes were harvested for biochemical and histopathology analysis.Results:All the conditioning techniques were able to increase the level of bothglutathione reductase and peroxidase, showing higher values in the rPOS group when compared to the lPOS. Also, thiobarbituric acid reactive substances were higher in all intervention groups when compared to SHAM, but rPOS had the lower rates of increase, showing the best result. The histopathology analysis showed that all groups had worst injury levels than SHAM, but rPOS had lower degrees of damage when compared to the lPOS, although it was not statistically significant.Conclusion:Remote postconditioning is a promising technique to reduce liver ischemia-reperfusion injury, once it increased antioxidants substances and reduced the damage.

Secukinumab Ameliorates Oxidative Damage Induced by Cerebral Ischemia-Reperfusion in Rats.

To investigate the histological and biochemical neuroprotective effects of secukinumab (SEC) on cerebral ischemia-reperfusion (IR) injury in Sprague-Dawley male rats. A total of 28 Sprague-Dawley male rats were randomly and equally divided into the following four groups: Sham, SEC, IR, and IR+SEC groups. Bilateral common carotid arteries were simultaneously separated and blocked for 15 minutes using two vascular mini clips in the IR and IR+SEC groups. The surgical procedure was similarly repeated in the Sham and SEC groups, but the carotid arteries were not clipped. Secukinumab was administered intraperitoneally to the SEC and IR+SEC groups once a week after the surgical procedure. Rat brain tissues were collected for biochemical analysis and histopathological examination 14 days after surgery. Cerebral IR caused abnormal changes in oxidative stress parameters by increasing the malondialdehyde (MDA) level and by decreasing the glutathione (GSH), catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) levels. IR also induced histopathological alterations, such as vascular congestion, hemorrhage, and cell infiltration in the rat brain tissues. Secukinumab treatment significantly decreased the MDA levels and increased the GPx, GSH, CAT, and SOD levels. In addition, secukinumab partially prevented histopathological alterations in the brain tissues. The percentage of immunohistochemically Caspase-3-positive cells was high in the IR group; however, SEC decreased the density of cells stained with Caspase-3. IR injury was found to cause oxidative and histopathological changes in rat brain tissues, and secukinumab treatment ameliorated these pathological effects. Therefore, secukinumab may be useful to prevent and treat oxidative stressinduced brain damage in patients with ischemic stroke.

The Preventive Effect of Cardiac Sympathetic Denervation Induced by 6-OHDA on Myocardial Ischemia-Reperfusion Injury: The Changes of lncRNA/circRNAs-miRNA-mRNA Network of the Upper Thoracic Spinal Cord in Rats.

In this study, we investigated whether chemical 6-hydroxydopamine (6-OHDA) stimuli caused cardiac sympathetic denervation (SD), and we analyzed gene expression profiles to determine the changes in the lncRNA/circRNAs-miRNA-mRNA network in the affected spinal cord segments to identify putative target genes and molecular pathways in rats with myocardial ischemia–reperfusion injury (MIRI). Our results showed that cardiac sympathetic denervation induced by 6-OHDA alleviated MIRI. Compared with the ischemia reperfusion (IR, MIRI model) group, there were 148 upregulated and 51 downregulated mRNAs, 165 upregulated and 168 downregulated lncRNAs, 70 upregulated and 52 downregulated circRNAs, and 12 upregulated and 11 downregulated miRNAs in the upper thoracic spinal cord of the SD-IR group. Furthermore, we found that the differential genes related to cellular components were mainly enriched in extracellular and cortical cytoskeleton, and molecular functions were mainly enriched in chemokine activity. Pathway analysis showed that the differentially expressed genes were mainly related to the interaction of cytokines and cytokine receptors, sodium ion reabsorption, cysteine and methionine metabolism, mucoglycan biosynthesis, cGMP-PKG signaling pathway, and MAPK signaling pathway. In conclusion, the lncRNA/circRNAs-miRNA-mRNA networks in the upper thoracic spinal cord play an important role in the preventive effect of cardiac sympathetic denervation induced by 6-OHDA on MIRI, which offers new insights into the pathogenesis of MIRI and provides new targets for MIRI.

The Effect of &amp;lt;i&amp;gt;Momordica charantia&amp;lt;/i&amp;gt; on Ovarian Ischemia-Reperfusion

Ovarian torsion is one of the gynecological emergencies that affect ovarian tissue integrity and fertility. In this study, we aim to investigate the effects of Momordica charantia (MC) on ovarian tissue injury induced by ovarian ischemia-reperfusion. Twenty-four rats were assigned to three groups: control group, ischemia-reperfusion (I/R) group and IR + MC group. 600 mg/kg MC extract were given rats via orogastric route. 3-hour ischemia and 3-hour reperfusion were performed for IR protocol. At the end of experiment, ovarian tissues were excised, fixed in zinc-formalin and processed for routine paraffin wax tissue embedding. Sections were stained with hematoxylin and eosin. Ovarian sections of control group showed regular histological appearance. In ovarian sections of I/R group, hemorrhage, fibrin accumulation, mononuclear cell infiltration and degenerated follicles were observed. I/R + MC group showed improved histopathology caused by I/R injury. We think that MC extract may protect ovarian tissue integrity and its histological structures.

Effects of Myocardial Ischemia-Reperfusion on Autophagy of Brain Cells and the Intervention Effect of Propofol in Type 2 Diabetic Rats

To investigate the expression of autophagy markers of brain cells and the effect of propofol on autophagy during myocardial ischemia-reperfusion in type 2 diabetic rats. 36 healthy male Sprague Dawley rats were randomly divided into 6 groups, 6 in each group, fed with high-sugar and high-fat diet for 8 w and intraperitoneal injection of streptozotocin to prepare the rat model of type 2 diabetes. The 6 groups are: diabetic rat with sham operation group, diabetic rat with myocardial ischemia reperfusion group, diabetic rat with myocardial ischemia reperfusion+propofol group, normal rat with sham operation, normal rat with myocardial ischemia reperfusion group, normal rat with myocardial ischemia reperfusion+propofol group[1]. In the normal rat with myocardial ischemia reperfusion+propofol group and diabetic rat with myocardial ischemia reperfusion+ propofol group, the left anterior descending coronary artery was ligated for 30 min and reperfused for 2 h after the propofol was injected with 6 mg•kg-1•h-1 for 10 min. Normal rat with myocardial ischemia reperfusion group and diabetic rat with myocardial ischemia reperfusion groups were pumped with 3 ml•kg-1•h-1 normal saline for 10 min, followed by ligation of the left anterior descending coronary artery for 30 min and reperfusion for 2 h. Arterial ligation was not performed in the normal rat with sham operation group and diabetic rat with sham operation groups. Brain tissue was taken to detect its levels of mechanistic target of rapamycin, phosphorylated mammalian target of rapamycin and Beclin-1 by Western blot. Compared with normal rat with sham operation group, phosphorylated mammalian target of rapamycin level was significantly decreased, and mechanistic target of rapamycin beclin-1 expression level was significantly increased in the other 5 groups (p<0.05). Compared with diabetic rat with myocardial ischemia reperfusion group, the expression level of phosphorylated mammalian target of rapamycin in diabetic rat with myocardial ischemia reperfusion+propofol group was increased, while beclin-1 and mechanistic target of rapamycin expression levels were significantly decreased (p<0.05). Compared with normal rat with myocardial ischemia reperfusion group, the level of mechanistic target of rapamycin in normal rat with myocardial ischemia reperfusion+propofol group was significantly increased, while the beclin-1 and mechanistic target of rapamycin expression levels were significantly decreased (p<0.05). Diabetes can promote the autophagy of brain cells during myocardial ischemia-reperfusion and aggravate the brain injury. Propofol can up-regulate the level of Phosphorylated mammalian target of rapamycin and down-regulate the expression of mechanistic target of rapamycin to alleviate the damage of brain cells after myocardial ischemia and reperfusion in normal rats and type 2 diabetic rats.

Relationship between Gastric Blood Perfusion and Gastric Mucosal Injury Induced by Acute Cerebrovascular Disease in Rats

This study aims to discuss the relationship between gastric perfusion and gastric mucosal injury induced by acute cerebrovascular disease in rats. Healthy adult male Wistar rats weighing 280-320 g are randomly divided into the following 4 groups: middle cerebral artery occlusion-reperfusion group, middle cerebral artery occlusion -sham group, gastric ischemia-reperfusion group and gastric ischemia-sham group, with 12 in each group. In gastric ischemia-reperfusion group, the similar changes occur to the mucous membrane of the rats, such as hyperaemia, edema, spotty or patchy hemorrhage and partial mucous exfoliation. There is no significant difference between middle cerebral artery occlusion-reperfusion group and gastric ischemia-reperfusion group in the number of gastrin cells and the expression of gas, but the number of gastrin cells and the expression of gas are significantly higher than those of their corresponding sham operation group, resulting in statistically significant difference. The gastric mucosal blood flow is significantly increased in the middle and high dose groups, which has significant difference compared with normal saline group (p<0.05). One of the important mechanisms of Calcitonin gene-related peptide protecting ischemic gastric mucosal injury is to increase gastric mucosal blood perfusion and improve microcirculation.

Alleviation of remote lung injury following liver ischemia/reperfusion: Possible protective role of vildagliptin

Lung injury is a serious condition encountered following hepatic ischemia/reperfusion (IR). This study aimed to explore whether a dipeptidyl peptidase-4 inhibitor agent vildagliptin (V) could alleviate the lung injury caused by hepatic IR in a rat model and if so elucidate its molecular protective mechanism. Three groups of rats were used. Sham group: received normal saline and exposed to a sham operation, IR group: received normal saline and subjected to the operation of hepatic I (45 min)/ R (180 min), V+IR group: received for 10 days intraperitoneal injection of V (10 mg/kg/day). After reperfusion, liver and lung were collected for biochemical and histological evaluation. Hepatic IR exhibited significant elevation in serum alanine aminotransferase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) enzyme levels, serum and lung malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-α) in addition to lung nitric oxide (NO) levels, hypoxia-inducible factor 1-alpha (HIF-1α) mRNA and protein levels, hepatocyte growth factor (HGF) mRNA expression, and inducible nitric oxide synthase (iNOS) mRNA and protein expressions in lung tissue along with a marked reduction in the serum and lung content of catalase in comparison to the sham group. Moreover, liver and lung injury in the IR group was detected by histopathological examination. Vildagliptin ameliorated markedly the biochemical changes as well as liver and lung architecture in comparison to the IR group. Vildagliptin mitigated the induced lung injury by hepatic IR via suppression of oxidative stress markers, pro-inflammatory cytokine TNF-α as well as the HIF1-α/iNOS/HGF expressions in lung tissue.

Application of vascular endothelial growth factor at different phases of intestinal ischemia/reperfusion: What are its effects on oxidative stress, inflammation and telomerase activity?

Intestinal ischemic reperfusion injury (IRI) represents a great challenge in clinical practice, with high morbidity and mortality. Vascular endothelial growth factor (VEGF), as a signal protein, contributes to vasculogenesis and angiogenesis. To evaluate the local effectiveness of VEGF following intestinal IRI and its relation with application time. Thirty Wistar albino rats were allocated to 5 groups and underwent laparotomy. The superior mesenteric arteries (SMA) were dissected in 4 groups, while the control group (Gr C) underwent a resection of small and large intestines. The VEGF group (Gr V) received VEGF following SMA dissection, with no further intervention, and the remaining 3 groups were subjected to ischemia for 90 min through occlusion of SMA and reperfusion for 4 h. Ischemic reperfusion group (Gr I/R) received no additional medication, while the remaining 2 groups received VEGF just before ischemia (Gr V+I/R) and during reperfusion (Gr I/R+V). Both applications of VEGF caused decreases in plasma levels of interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), intestinal malondialdehyde (MDA), oxidized glutathione, protein carbonyl levels, and increases in intestinal total glutathione and superoxide dismutase (SOD) levels. Telomerase activity, which disappeared for Gr I/R, was found to be elevated following both treatment groups. Similarly, the histopathological scores were found better for both treatment groups, but Gr V-I/R represented best outcomes. The findings of our study revealed that VEGF, applied either before ischemia or during reperfusion, is effective on local damage following intestinal IRI. By interpreting the biochemical analysis and histopathological findings, we conclude either treatment option to be considered according to the reason of intestinal IRI.

Effect of electroacupuncture preconditioning on cell apoptosis mediated by mitochondrial reactive oxygen species in myocardial ischemia/reperfusion injury rats

To observe the effect of electroacupuncture (EA) preconditioning on cell apoptosis and the content of mitochondrial reactive oxygen species (ROS) in rats with myocardial ischemia/reperfusion injury (MIRI), so as to explore their mechanisms underlying improvement of MIRI. Eighty male Wistar rats were randomly divided into control, sham, ischemia reperfusion (IR) and EA groups, with 20 rats in each group. Rats of the control, sham and IR groups were just banded on the boards for 30 min, once daily for 7 days. Before modeling, EA (2 Hz, 1 mA) was applied to "Neiguan" (PC6), "Zusanli" (ST36), "Guanyuan"(CV4) for 20 min, once daily for 7 successive days in the EA group. The MIRI model was established by occlusion of the left anterior descending branch of the left coronary artery for 20 min, followed by reperfusion for 30 min. Ventricular arrhythmia (VA) score was used to evaluate arrhythmia. Enzyme-linked immunosorbent assay (ELISA) was used to detect the level of CK-MB. DHE staining was used to detect the content of reactive oxygen species (ROS). The gene expression levels of cytochrome C (Cyt-C), Caspase-9 and Caspase-3 were detected by real-time fluorescent quantitative PCR. Compared with the sham group, VA score, serum CK-MB content, ROS content in heart tissue and Cyt-C, Caspase-9 and Caspase-3 gene expression were significantly up-regulated in the MIRI group (all P<0.01). Following the intervention, the increased VA score, serum CK-MB content, ROS content in heart tissue, Cyt-C, Caspase-9 and Caspase-3 gene expression were all reversed in the EA group compared with the MIRI group (all P<0.01). The protective effect of EA preconditioning on MIRI may be based on the regulation of ROS mediated-apoptosis pathway.

The structural-spatial reorganization of the arterial bed of the femur, knee and shin areas of the hind limbs of the rats

The structural-spatial reorganization of the arterial bed of the femur, knee and shin areas of the hind limbs of the rats