Ischemia-reperfusion Group Research Articles

Ischemic Postconditioning Attenuates Myocardial Ischemia-Reperfusion-Induced Acute Lung Injury by Regulating Endoplasmic Reticulum Stress-Mediated Apoptosis.

To explore the effect of ischemic postconditioning on myocardial ischemia-reperfusion-induced acute lung injury (ALI). Forty adult male C57BL/6 mice were randomly divided into sham operation group (SO group), myocardial ischemia-reperfusion group (IR group), ischemic preconditioning group (IPRE group) and ischemic postconditioning group (IPOST group) (10 mice in each group). Anterior descending coronary artery was blocked for 60 min and then reperfused for 15 min to induce myocardial IR. For the IPRE group, 3 consecutive cycles of 5 min of occlusion and 5 minutes of reperfusion of the coronary arteries were performed before ischemia. For the IPOST group, 3 consecutive cycles of 5 min reperfusion and 5 minutes of occlusion of the coronary arteries were performed before reperfusion. Pathological changes of lung tissue, lung wet-to-dry (W/D) weight ratio, inflammatory factors, oxidative stress indicators, apoptosis of lung cells and endoplasmic reticulum stress (ERS) protein were used to evaluate lung injury. After myocardial IR, lung injury worsened significantly, manifested by alveolar congestion, hemorrhage, structural destruction of alveolar septal thickening, and interstitial neutrophil infiltration. In addition, lung W/D ratio was increased, plasma inflammatory factors, including interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-17A, were increased, malondialdehyde (MDA) activity of lung tissue was increased, and superoxide dismutase (SOD) activity was decreased after myocardial IR. It was accompanied by the increased protein expression levels of ERS-related protein glucose regulatory protein 78 (GRP78), CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP), and caspase-12, and the increased apoptotic indices of lung tissues. IPOST can effectively improve myocardial IR-induced ALI by inhibiting ERS-induced apoptosis of alveolar epithelial cells.

Leptin alleviated ovarian ischemia-reperfusion injury in rats via modulation of Sirt-1/Nrf2 and TLR4/NF-kB/caspase-3 signaling pathways.

Objective. Ovarian torsion is a gynecological emergency that occurs mostly during the female reproductive years due to ovarian masses or surgical manipulation. This work aims to explore the probable protective effect of leptin on rat ovaries due to ischemia-reperfusion (IR) injury. Methods. Wistar albino rats were divided into four groups: 1) control group; 2) ovarian IR group (OVIR); 3) leptin group I [OVIR + leptin (10 µg/kg body weight, b.w.)]; and 4) leptin group II (OVIR + leptin (100 µg/kg b.w.)]. Serum levels of estradiol and anti-Mullerian hormone (AMH) were measured. Levels of oxidative stress and inflammatory markers in ovarian tissue were determined along with the expression of sirtuin 1 (Sirt1), nuclear erythroid factor-2 (Nrf2), cyclooxygenase-2 (COX-2), nuclear factor kappa (NF-κB), toll like receptor-4 (TLR4), and caspase-3. Results. Serum estradiol and AMH levels were decreased with increased expression of COX-2, TLR4, caspase-3, and NF-κB and decreased expression of Sirt1and Nrf2 in ovary of the OVIR group, which were improved by exogenous administration of both leptin doses. Conclusion. Leptin administration dose-dependently reduced the severity of OVIR injury via modulation of Sirt-1/Nrf2 and TLR4/NF-kB/caspase-3 signaling pathways. Thus, leptin may be used as an adjuvant measure to prevent ovarian damage and improve the outcomes. However, clinical studies are needed to evaluate these results in humans.

The effect of protocatechuic acid on ovarian histopathology and reserve in rat ovarian torsion model.

The aim of the study is to investigate the effects of Protocatechuic Acid (PCA), which is an antioxidant, anti-inflammatory and anti-apoptotic agent, on ovarian tissue and ovarian reserve against ischemia-reperfusion (IR) injury in a rat ovarian torsion model. Reactive oxygen radicals cause histopathological changes in the ovarian tissue during the reperfusion phase. PCA may have protective effects on ovarian tissue and reserve due to its antioxidant and antiapoptotic properties. A total of 24 Wistar adult female rats were divided into 3 groups as the control (sham operation, n = 8), IR (Ischemia-Reperfusion, n = 8), and IR+PCA (Ischemia-Reperfusion + 80 mg/kg protocatechuic acid, n = 8). The IR and IR + PCA groups underwent 3 hours of ischemia followed by 3 hours of ovarian reperfusion. Protocatechuic acid (80 mg/kg) was administered to the IR+PCA group 30 minutes before reperfusion. After reperfusion, the ovaries were removed for histopathological and biochemical examination. Histopathological score and TUNEL+ cell count were significantly lower and AMH expression level was significantly higher in the IR+PCA group when compared to the IR group (p <0.05). However, in the comparison of the follicle counts, there was no statistically significant difference between all groups. Due to the increase in antioxidant activity, the MDA levels were found to be significantly lower in the IR+PCA group compared to the IR group (p < 0.05). Protocatechuic acid may be an effective antioxidant in protecting ovarian tissue and follicle reserve against IR injury of the ovary (Tab. 1, Fig. 4, Ref. 36).

Exaggerated blood pressure response to static exercise in hindlimb ischemia-reperfusion.

Peripheral artery disease (PAD) reduces the blood flow supply in the affected limbs as one of the significant cardiovascular concerns. Revascularization surgery in the femoral artery plays a central role in treating PAD. Exercise is also a rehabilitation strategy suggested for PAD patients to improve vascular functions. However, the effects of limb ischemia-reperfusion (IR), one of the most predominant complications in revascularization surgery, on exercise-induced arterial blood pressure (BP) response are poorly understood. In the present study, we determined 1) the blood flow status in the hindlimb muscles of rats (plantar muscle, red and white portions of gastrocnemius) with different time points of the hindlimb IR; and 2) the BP response to static muscle contraction in rats at different time points after the blood flow reperfusion procedure. Results of this study indicated that, compared with the Sham group, the blood flow in the hindlimb muscles evaluated by Evans blue concentration was significantly reduced at 6h of femoral artery occlusion (FAO 6h) (vs. sham control, p < 0.05). The decreased blood flow was gradually recovered after the blood flow reperfusion for 18 (IR 18h), 66 (IR 66h), and 114 (IR 114h) hours (p < 0.05 vs. FAO 6h for all IR groups). The response of mean arterial pressure was 20 ± 4mmHg in Sham rats (n = 7); 32 ± 10mmHg in IR 18h rats (n = 10); 27 ± 7mmHg in IR 66h rats (n = 13); 26 ± 4mmHg in IR 114h rats (n = 9) (p < 0.05 vs. Sham for all groups). No significant difference was observed in the peak-developed tension during muscle contraction among all the groups (p > 0.05). In conclusion, static exercise-induced BP response is exaggerated following IR. Whereas the BP response is not statistically significant but tends to decrease with a prolonged IR time, the exaggerated BP response remains through time points from post-IR 18h-114h.

Alpha-1-Antitrypsin Protects Vascular Grafts of Brain-Dead Rats Against Ischemia/Reperfusion Injury

IntroductionEndothelial dysfunction is a potential side effect of brain death (BD). Ischemia/reperfusion (IR) injury during heart transplantation may lead to further endothelial damage. Protective effects of alpha-1-antitrypsin (AAT), a human neutrophil serine protease inhibitor, have been demonstrated against IR injury. We hypothesized that AAT protects brain-dead rats’ vascular grafts from IR injury. MethodsDonor rats were subjected to BD by inflation of a subdural balloon. After 5.5 h, aortic rings were immediately mounted in organ baths (BD, n = 6 rats) or preserved in saline, supplemented either with vehicle (BD-IR, n = 8 rats) or AAT (BD-IR + AAT, n = 14 rats) for 24 h. During organ bath experiment, rings from both IR groups were exposed to hypochlorite to simulate warm reperfusion-associated endothelial injury. Endothelial function was measured ex vivo. Immunohistochemical staining for caspases was carried out and DNA-strand breaks were evaluated using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling. Data are presented as median (interquartile range). ResultsAAT improved IR-induced decreased maximum endothelium-dependent vasorelaxation to acetylcholine in the BD-IR + AAT aortas compared to the BD-IR group (BD: 83 (9-28) % versus BD-IR: 49 (39-60) % versus BD-IR + AAT: 64 (24-42) %, P < 0.05). Additionally, an increase in the rings’ sensitivity to acetylcholine was noted after AAT (pD2-value: BD-IR + AAT: 7.35 (7.06-7.89) versus BD-IR: 6.96 (6.65-7.21), P < 0.05). Caspase-3, -8, -9, and -12 immunoreactivity and the number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells were significantly decreased by AAT. ConclusionsAAT alleviates endothelial dysfunction, prevents increased caspase-3, -8, -9, and -12 levels, and decreases apoptotic DNA breakage due to BD and IR injury. This suggests that AAT treatment may be therapeutically beneficial to reduce IR-induced vascular damage.

Danhong injection alleviates cerebral ischemia-reperfusion injury by inhibiting mitochondria-dependent apoptosis pathway and improving mitochondrial function in hyperlipidemia rats

Cerebral ischemia threatens human health and life. Hyperlipidemia is a risk of cerebral ischemia. Danhong injection (DHI) is a traditional Chinese medical preparation for the treatment of cerebrovascular diseases. However, the effects of DHI on mitochondria-dependent apoptosis and mitochondrial function following cerebral ischemia in hyperlipidemia rats are not clear. In this study, SD rats were fed by high-fat diet for six weeks to establish the hyperlipidemia model, except for the sham and ischemia-reperfusion (I/R) groups. Hyperlipidemia rats were assigned into I/R + high-fat diet (HFD) group, DHI 1 mL/kg group, and DHI 2 mL/kg group. DHI was administrated to the drug group via caudal vein for seven consecutive days (once per day). Subsequently, rats underwent middle cerebral artery occlusion (MCAO) for 1 h and reperfusion for 24 h. The results showed that DHI significantly reduced cerebral infarction volume, ameliorated neurological function, improved pathological changes, and inhibited apoptosis. DHI could significantly restore the levels of mitochondrial respiratory chain complexes I-IV, increase the ATP content and COX activity, and decrease the level of OFR in the ischemic brain mitochondria of hyperlipidemia rats after I/R. DHI significantly regulated the levels of cytochrome c (Cyt c), Apaf1, Bax, Bcl-2, Caspase-3, and Caspase-9 in brain tissue, and improved mitochondrial dynamics (Mfn1, Mfn2, OPA1, Drp1, and Fis1). The results indicate that DHI could alleviate ischemic brain injury in hyperlipidemia rats, and the mechanism may be to improve mitochondrial function by restoring the mitochondrial respiratory chain and changing the protein balance of mitochondrial fusion and fission, and inhibiting mitochondria-dependent apoptosis.

Stimulation of functional recovery via neurorepair mechanisms by the traditional Japanese Kampo medicine, Ninjin'yoeito, and physical exercise in a rat ischemic stroke model

Ethnopharmacological relevanceNinjin'yoeito (NYT), a traditional Japanese Kampo medicine consisting of 12 herbs, has been reported to improve cognitive dysfunction, depression, and neurological recovery in patients with neurovascular diseases such as Alzheimer's disease and stroke. Several studies have reported that the NYT components exert neurotrophic, neurogenic, and neuroprotective effects. In addition, exercise enhances neuroprotection and functional recovery after stroke. Rehabilitative exercises and pharmacological agents induce neurophysiological plasticity, leading to functional recovery in stroke patients. These reports indicate that NYT treatment and exercise may promote functional recovery following stroke through their beneficial effects. However, no study has determined the effects of NYT and the possible mechanisms of neurorepair and functional recovery after stroke. Aim of the studyThis study aimed to investigate the combined effects of NYT and exercise on neuroprotection and functional recovery and the underlying mechanisms in a rat ischemic stroke model. Materials and methodsStroke was induced with 60-min middle cerebral artery occlusion (MCAO) followed by reperfusion in adult male Sprague-Dawley rats. After stroke, the rats were assigned to four groups: ischemia reperfusion (IR), NYT, exercise (Ex), and NYT + Ex. NYT-treated rats were fed a diet containing 1% NYT one day after stroke. Exercise was performed using a motorized treadmill for 5 days a week (8–15 m/min, 20 min/day), starting 3 days after stroke. The NYT treatment and exercise were continued for 4 weeks after the stroke. Infarct volume, neurological deficits, sensorimotor functions, expression of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase A (TrkA) and B (TrkB), caspase-3 activity, and the p-Akt/Akt ratio were examined by immunohistochemistry and western blotting. ResultsCompared to the IR group, all treated groups indicated reduced infarct volumes. The NYT + Ex group showed significantly improved waking time and beam walking score compared with the IR group. The expression of NGF/TrkA/p-TrkA and BDNF/TrkB was significantly increased in the NYT + Ex group compared with those in the IR group, whereas the number of caspase-3 positive cells around the lesion was significantly lower in the NYT + Ex group than in the IR group. In addition, the ratio of p-Akt/Akt was significantly higher in the NYT + Ex group than in the IR group. ConclusionsThis study suggests that NYT in combination with exercise provides neuroprotective effects and improves sensorimotor function by stimulating NGF/TrkA and BDNF/TrkB, and by activating the Akt pathway in ischemic stroke of rats. NYT may be an effective adjunctive agent in post-stroke rehabilitation.

Dexmedetomidine Reduce Multiple Organ Injury Induced by Lung Ischemia/ Reperfusion of Mice Through Inhibiting Endoplasmic Reticulum Stress Response

To investigate the effect of Dexmedetomidine reduce brain, myocardium and kidney injury induced by lung ischemia/reperfusion of mice through inhibiting endoplasmic reticulum stress response. SPF C57BL/6J male mice were randomly divided into 5 groups (n = 10): the sham operation group (group sham), the ischemia reperfusion Group (Group I/R), the Atipamezole Group (Group Atip), dexmedetomidine Group (Group-DEX) and dexmedetomidine+AtipamezoleGroup (Group DA). Lung ischemia reperfusion models were established with the method of 30min in-vivo left hilus occlusion followed by 180min reperfusion. In addition to the steps same as Group I/R, the mice in Groups Atip, Dex and DA were given Atip(250μg/kg), Dex(20μg/kg), and Dex+ Atip(20μg/kg+250μg/kg) respectively by intraperitoneal injection 30min before hilar occlusion. After reperfusion, the blood was taken from the eye-orbit to determine the activity of serum CK-MB and LDH and the levels of serum creatinine and urea nitrogen. The brain tissue was taken to determine the brain water content. The tissue of myocardium, brain and kidney was taken to observe the cellular morphology change under the light microscope. The expression of Caspase3 activity in heart, brain and kidney was determined with Thermos Scientific Microplate Reader. The TUNEL method was used to detect the apoptotic index of heart, brain and kidney. The Western blot and RT-PCR were used to determine the expression of proteins and mRNA of JNK, Caspase12, CHOP and GRP78. Compared with Group Sham, obvious injury in the tissue of myocardium, brain and kidney was observed in the other four groups under the light microscope. The activity of CKMB and LDH, and the levels of serum creatinine, urea nitrogen and brain water content were significantly increased as well. The apoptotic index, Caspase3 activity, and the expression of the proteins and mRNA of JNK, Caspase12, CHOP and GRP78 were also significantly elevated. Compared with Group I/R, Atip and DA, the mitigated injury in the myocardium, brain and kidney was observed in Group DEX under the light microscope. The activity of CK-MB and LDH, and the levels of serum creatinine, urea nitrogen and brain water content were decreased and the apoptotic index, Caspase3 activity, and the expression of the proteins and mRNAs of JNK, Caspase12 and CHOP were also significantly decreased in Group DEX, but the proteins and mRNA expression of GRP78 were significantly elevated. For the comparison among theGroup I/R, Atip and DA, there is no significant difference was found.(grp78).The pre-administration of DEX can mitigate the heart, brain and kidney injury induced by lung ischemia reperfusion. The mechanism may be related to the activation of α2-adrenergic receptor and inhibition of endoplasmic reticulum over-response.

Functional Blockage of S100A8/A9 Ameliorates Ischemia-Reperfusion Injury in the Lung.

(1) Background: Lung ischemia-reperfusion (IR) injury increases the mortality and morbidity of patients undergoing lung transplantation. The objective of this study was to identify the key initiator of lung IR injury and to evaluate pharmacological therapeutic approaches using a functional inhibitor against the identified molecule. (2) Methods: Using a mouse hilar clamp model, the combination of RNA sequencing and histological investigations revealed that neutrophil-derived S100A8/A9 plays a central role in inflammatory reactions during lung IR injury. Mice were assigned to sham and IR groups with or without the injection of anti-S100A8/A9 neutralizing monoclonal antibody (mAb). (3) Results: Anti-S100A8/A9 mAb treatment significantly attenuated plasma S100A8/A9 levels compared with control IgG. As evaluated by oxygenation capacity and neutrophil infiltration, the antibody treatment dramatically ameliorated the IR injury. The gene expression levels of cytokines and chemokines induced by IR injury were significantly reduced by the neutralizing antibody. Furthermore, the antibody treatment significantly reduced TUNEL-positive cells, indicating the presence of apoptotic cells. (4) Conclusions: We identified S100A8/A9 as a novel therapeutic target against lung IR injury.

Activation of the ERK1/2 pathway mediates the neuroprotective effect provided by calycosin treatment

Calycosin is a natural product extracted from some plant families and exhibits various biological properties. But the effect of calycosin on cerebral ischemia–reperfusion injury has not been fully elucidated. In this study, the neuroprotective effect of calycosin treatment on the differentiated SH-SY5Y cells exposed to OGD was evaluated using MTT and flow cytometry. Rats that were pretreatment with calycosin were subjected to MCAO, neurological behavior scores and brain infarct volume were evaluated. The protein expression of pERK/ERK were assessed using Western blot. siRNA-pERK and U0126 were administered to investigate the impact of the ERK pathway on calycosin preconditioning. The results demonstrated the neuronal viability in the calycosin-treated SH-SY5Y cells increased significantly, and the rate of apoptosis decreased compared with the Oxygen-glucose deprivation only SH-SY5Y cells. Calycosin pretreatment reduced infarct volume and improved neurological outcome in rats subjected to MCAO. Administration of calycosin increased the ratio of pERK/ERK expression, which was down-regulated in ischemia–reperfusion group. Down-regulation of pERK/ERK significantly attenuated the neuroprotective effect induced by calycosin pretreatment in vitro and in vivo. We concluded calycosin treatment could induce a neuroprotective effect against ischemia, which was related to the regulation of the ERK1/2 pathway.

Baicalein Alleviates Testicular Ischemia-Reperfusion Injury in a Rat Model of Testicular Torsion-Detorsion.

Testicular torsion/detorsion-induced ischemia/reperfusion injury is partly due to the overgeneration of reactive oxygen species. Baicalein, a main bioactive constituent derived from the dried root of Scutellaria baicalensis Georgi, possesses powerful antioxidative and anti-inflammatory properties. Therefore, we designed the research to explore the possible protective effect of baicalein against testicular ischemia-reperfusion injury. Sprague-Dawley rats were randomized into 4 groups, including control, testicular ischemia-reperfusion, testicular ischemia-reperfusion+vehicle injection, and testicular ischemia-reperfusion+baicalein therapy groups. The control group received surgical exposure of the left testis without torsion-detorsion. In the testicular ischemia-reperfusion group, the left testis underwent 720° counterclockwise torsion for two hours and then was allowed detorsion. Rats in the testicular ischemia-reperfusion+vehicle injection group received intraperitoneal injection of the vehicle at detorsion. In the baicalein-treated group, the intraperitoneal administration of baicalein dissolved in the vehicle was performed at detorsion. At four hours or three months following testicular detorsion, testicular tissues were removed to detect the levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) which can recruit neutrophils into the testis, myeloperoxidase activity (an index of neutrophil infiltration in the testis), protein expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in neutrophils which can catalyze reactive oxygen species production, malondialdehyde concentration (a common marker of reactive oxygen species), and spermatogenesis. Both testicular ischemia-reperfusion and testicular ischemia-reperfusion+vehicle injection significantly increased the TNF-α and IL-1β levels, myeloperoxidase activity, NADPH oxidase protein expression, and malondialdehyde concentration, while decreased spermatogenesis in ipsilateral testes. In contrast, baicalein administration remarkably reduced TNF-α and IL-1β levels, myeloperoxidase activity, NADPH oxidase protein expression, and malondialdehyde concentration and also elevated spermatogenesis in ipsilateral testes. The results of our experiment demonstrate that baicalein alleviates testicular ischemia-reperfusion injury by inhibiting TNF-α and IL-1β secretion, neutrophil infiltration in the testis, and NADPH oxidase protein expression in neutrophils to reduce reactive oxygen species production.

Effect of ellagic acid on damage caused by hepatic ischemia reperfusion in rats.

Ischemia (I) causes lack of oxygen delivery to the tissues, leading to hypoxia and cellular damage. Reperfusion (R) is the re-blooded of the tissue; however, it may cause more tissue damage than ischemia alone in some cases. During IR, number of free radicals and metabolic by-products increases. To prevent this, cellular antioxidant system is activated but it may not be enough to restore the cellular activities. The aim of this study was to investigate the potential protective effect of Ellagic Acid on damage caused by hepatic IR in rats. Thirty rats were divided into three groups: (1) Sham group - no drug administration but only midline laparotomy was performed in the abdomen; (2) Ischemia-Reperfusion (IR) group - ischemia was applied for 1 hour by sealing the portal vein and hepatic artery, then vessels were reperfused for 6 hours; (3) IR+Elagic Acid (EA) group - after IR, 10 mg/kg of EA was given intraperitonially to the rats once a day for 28 days. Oxidative stress markers were analyzed by blood collection. Hepatic tissues were processed for histological and immunohistochemical analysis. MDA level and MPO activity were increased and GSH content was decreased after IR group was compared to sham group. After EA treatment, these values were improved in IR+EA group. IR caused hepatocyte degeneration, sinusoidal dilatation, leukocyte infiltration and disintegrity of hepatic tissue. EA administration improved histopathology after IR. IR injury increased TNF-α and Caspase-9 expression in hepatocytes and vascular endothelial cells in IR group; however, both decreased in EA-received group. Ellagic Acid may reduce oxidative stress level and prevent induction of inflammation and cell death against hepatic IR.

JNK and p38 gene and protein expression during liver ischemia-reperfusion in a rat model treated with silibinin.

Signal transduction of mitogen-activated protein kinases (MAPKs) is activated during ischemia. In this study, c-Jun N-terminal Kinase (JNK) and p38 MAPK (p38) gene and protein expression were evaluated as two members of the MAPK family during liver ischemia-reperfusion in rats. Thirty-two male Wistar rats were divided into four groups of eight: Vehicle, ischemia-reperfusion (IR), ischemia-reperfusion+silibinin (IR+SILI), and SILI. The IR and IR+SILI groups differed from the other two groups in that they underwent one hour of ischemia followed by three hr of reperfusion. The Vehicle and IR groups received normal saline while the SILI and IR+SILI groups were treated with silibinin (50 mg/kg). At the end of the reperfusion time, blood and ischemic liver tissue were collected for further experiments. The expression of JNK and p38 gene, the amount of serum hepatic injury indices, and malondialdehyde (MDA) in the IR group increased significantly compared with the vehicle group. The JNK and p38 gene expression decreased significantly in the IR + SILI group compared with the IR group. Glutathione peroxidase (GPx) and total antioxidant capacity (TAC) levels decreased in the IR group while increasing in the IR+SILI group. Histological examination showed that silibinin significantly reduced the severity of hepatocyte degradation. Western blot results were completely consistent with real-time PCR results. The possible pathways of the protective effect of silibinin against hepatic ischemia damages is to reduce the expression of the p38 and JNK gene and protein.

Investigating the protective effect of glutamine against cerebral ischemia and bilateral carotid occlusion in rats.

This study aims to investigate the protective effects of glutamine against cerebral injury resulting from cerebral ischemia-reperfusion by bilateral carotid occlusion in rats. Eighteen Wistar albino rats were randomly divided into three equal groups: 1) control group; 2) ischemia-reperfusion group which underwent clamping of the carotid artery for 20 min; and 3) ischemiareperfusion + glutamine group which was treated with two doses of glutamine (1 g/kg) prior to the same clamping procedure as the ischemia-reperfusion group. All rats were sacrificed 24 h after the experiment. Their brain tissue was removed, separated into right and left hemispheres, and sent for analysis. Biochemical analysis was used to determine the oxidant parameters, antioxidant parameters, and glutathione levels in brain tissue. In the histopathological analysis of the brain tissue, ischemic markers such as red neurons, spongiosis, and satellitosis were examined. Biochemical examination revealed that the levels of malondialdehyde and ferric reducing antioxidant power in the ischemia-reperfusion group were significantly higher than those in the control and ischemia-reperfusion + glutamine groups (p<0.05). The histopathological findings revealed that the levels of red neurons, satellitosis, and spongiosis in the ischemia-reperfusion group were significantly higher than those in the control group (p<0.05). The red neuron and spongiosis levels in the ischemia-reperfusion + glutamine group were significantly higher than those in the control group (p<0.05). Our study findings indicate that glutamine treatment has a protective effect against ischemia-reperfusion-induced brain damage in rats.

Sufentanil promotes autophagy and improves ischemia-reperfusion-induced acute kidney injury via up-regulating microRNA-145.

Sufentanil has a good protective effect on myocardial and liver injury caused by ischemia reperfusion (IR), but its protective effect on kidney is still unclear. This study aims to investigate whether sufentanil can prevent IR-induced acute kidney injury (AKI) and to determine whether its efficacy is related to miR-145-mediated autophagy. A total of 40 rats were randomly divided into 5 groups (n=8 in each group): A sham group, an IR group, a sufentanil group, a sufentanil+miR-145 inhibitor control group (an anti-NC group) and a sufentanil+miR-145 inhibitor group (an anti-miR-145 group). Except for the sham group, the other groups established a rat AKI model induced by IR. The sufentanil group, the sufentanil+anti-NC group, and the sufentanil+anti-miR-145 were injected with sufentanil (1 μg/kg) through femoral vein 30 min before ischemia. The sufentanil+anti-NC group and the sufentanil+anti-miR-145 group were injected with miR-145 inhibitor control or anti-miR-145 (80 mg/kg) through the tail vein before sufentanil pretreatment. The structure and function of kidneys harvested from the rats were evaluated, and the protein levels of autophagy-related proteins, oxidative stress levels, and apoptosis levels were measured. Compared with the IR group, the renal structure and function were improved in the sufentanil group. The levels of blood urea nitrogen (BUN), creatinine (Cr), urinary kidney injury molecule 1 (KIM-1), neutrophil gelatinase related lipid transporter (NGAL), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and ROS were significantly decreased (all P<0.05). In addition, compared with the IR group, the levels of Beclin-1 and LC3 in renal tissues in the sufentanil group were significantly increased (both P<0.05), and the apoptosis in renal tissues was significantly reduced (P<0.05). Compared with the sufentanil+anti-NC group, the levels of BUN, Cr, KIM-1, NGAL, TNF-α, IL-1β, IL-6 and ROS in the sufentanil+anti-miR-145 group were significantly increased (all P<0.05), the levels of Beclin-1 and LC3 in renal tissues were significantly decreased (both P<0.05), and the apoptosis in renal tissues was significantly increased (P<0.05). Sufentanil can prevent the AKI induced by IR, which is related to the up-regulation of miR-145-mediated autophagy.

Role of hypoxia inducible factor 1α/Bcl-2/adenovirus E1B 19-kDa interacting protein 3 in alleviating effect of interleukin-4 on cerebral ischemia reperfusion injury in mice.

Cerebral ischemia reperfusion injury (CIRI) is the pathophysiological basis of various cerebrovascular diseases. The aim of this study was to explore the role of HIF-1α/BNIP3 in the alleviating effect of IL-4 on CIRI in mice. Mice were randomly divided into sham operation (Sham), ischemia reperfusion (IR), IL-4, HIF-1α inhibitor 2ME2 and IL-4+2ME2 groups. Middle cerebral artery occlusion model was established. After 24-h reperfusion, neurologic deficit score (NDS) was given. Cerebral infarction volume and brain water content were measured by 2,3,5-triphenyltetrazolium chloride staining and dry-wet weights, respectively. Apoptosis was detected by TUNEL staining. SOD, MDA and ROS levels, and HIF-1α, BNIP3, LC3II and Beclin-1 expressions were detected through colorimetry and Western blotting, respectively. Compared with IR group, NDS, cerebral infarction volume, brain water content, apoptosis rate, and MDA and ROS levels decreased, while SOD, HIF-1α, BNIP3, LC3-II and Beclin-1 levels increased in IL-4 group (P<0.05). 2ME2 and IL-4+2ME2 groups had decreased NDS, cerebral infarction volume, brain water content, apoptosis rate and MDA, ROS, HIF-1α, BNIP3, LC3-II and Beclin-1 levels, but increased SOD level compared with those of IL-4 group (P<0.05). IL-4 reduces apoptosis and oxidative stress through activating the HIF-1α/BNIP3 pathway, thereby alleviating mouse CIRI.

The effect of post-reperfusion levosimendan in an experimental intestinal ischemia–reperfusion model

BackgroundLevosimendan has been reported to have a positive effect on ischemia–reperfusion injury. Herein, we aimed to evaluate the effects of levosimendan applied after reperfusion in an experimental intestinal injury-reperfusion (IR) model.MethodsTwenty-one Wistar-albino male rats were separated into three groups: Sham group (n = 7): solely superior mesenteric artery (SMA) was dissected after laparotomy; intestinal ischemia–reperfusion group (IIR, n = 7): SMA was clamped for 60 min and unclamped for 120 min to cause ischemia–reperfusion; IIR + levosimendan group (IIR + L, n = 7): levosimendan was administered in ischemia–reperfusion model. The mean arterial pressures (MAP) were measured in all groups. MAP measurements were performed at the end of stabilization, at the 15th, 30th, and 60th minute of ischemia; at the 15th, 30th, 60th, and 120th minute of reperfusion; and at the end of levosimendan bolus application and when levosimendan infusion concluded. Reperfusion injury was evaluated with tissue malondialdehyde (MDA) and by Chiu score.ResultsMAP at 15 min, 30 min, and 60 min of reperfusion was lower in IIR and IIR + L groups compared with basal inter-group measurements. Decline in MAP at 30 min after reperfusion was statistically significant in IIR and IIR + L groups when compared with the sham group. There was no significant difference between MDA levels in the groups. Chiu score was significantly lower in the sham group when compared to IIR and IIR + L groups and higher in IIR when compared to the IIR + L group.ConclusionLevosimendan leads to a decrease in intestinal damage although it did not affect lipid peroxidation and MAP when administered after reperfusion in an experimental intestinal IR model.

Ischemia challenged epicardial adipose tissue stem cells-derived extracellular vesicles alter the gene expression of cardiac fibroblasts to cardiomyocyte like phenotype

The present study hypothesizes that the ischemic insults activate epicardial adipose tissue-derived stem cells (EATDS) to secrete extracellular vesicles (EVs) packed with regenerative mediators to alter the gene expression in cardiac fibroblasts (CF). EATDS and CF were isolated from hyperlipidemic microswine and EVs were harvested from control, simulated ischemia (ISC) and ischemia-reperfusion (ISC/R) groups. The in vitro interaction between ISC–EVs and CF resulted in the upregulation of cardiomyocyte-specific transcription factors including GATA4, Nkx2.5, IRX4, and TBX5 in CF and the healing marker αSMA and the downregulation of fibroblast biomarkers such as vimentin, FSP1, and podoplanin and the cardiac biomarkers such as troponin-I and connexin-43. These results suggest a cardiomyocyte-like phenotype as confirmed by immunostaining and Western blot. The LC-MS/MS analysis of ISC–EVs LGALS1, PRDX2, and CCL2 to be the potent protein mediators which are intimately involved in versatile regenerative processes and connected with a diverse array of regenerative genes. Moreover, the LGALS1+, PRDX2+, and CCL2+ EATDS phenotypes were deciphered at single cell resolution revealing corresponding sub-populations with superior healing potential. Overall, the findings unveiled the healing potential of EATDS-derived EVs and sub-populations of regenerative EATDS promising novel translational opportunities in improved cardiac healing following ischemic injury.

MESNA HAS ANTIOXIDANT POTENTIAL ON INTESTINE, LIVER, KIDNEY AND LUNG INJURY INDUCED BY INTESTINAL ISCHEMIA/REPERFUSION

An ischemia/reperfusion (IR) injury of small intestine is a serious and common condition that is a result of the blockage of the superior mesenteric artery (SMA) due to some significant clinical problems. In the present study, we evaluated the effect of Mesna on systemic injury induced by IR in small intestine and liver, kidney and lung of rats. Thirty-two Wistar albino female rats were randomly divided into four groups as control, ischemia, IR (Sham) and IR+Mesna. Ischemia period was executed by clamping SMA for 2 h and after when reperfusion was permitted by removing the clamp from SMA for 2 h. Superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) activities were measured spectrophotometrically in the tissues. Microscopic examination was performed with Hematoxylin-Eosin (H&amp;amp;E) staining for light microscopy and double staining (Uranyl acetate and Reynolds’lead citrate) for electron microscopy. Oxidative damage was determined in ischemia (p &amp;lt; 0.05) and IR groups (p &amp;lt; 0.05) by Chiu score in small intestine and also antioxidant enzyme activities in all groups. Significant recovery in SOD, GPx and CAT activities in IR+Mesna group was determined but the effect of oxidative damage was not reduced significantly histopatologically. Mesna treatment caused recovery in SOD, GPx and CAT activities but not achieved an improvement in the histopathologic findings in level of light microscopy in IR damages but contains the signs of improving at electron microscopy level in Mesna dose and application time of IR.

TNF-α and IL-10 levels in hipoxic ischemic rat brain receiving stem cell

To investigate the effect of intracerebral adipose neural stem cell transplantation in the inflammatory process after brain HI. The study used 16male Wistar rats aged 2 months which were randomly divided into the following group: Ischemia-Reperfusion group (IR, n=8) and ANSC-treated group (IR+ANSC, n=8). IR was performed by right common carotid artery occlusion for 2 hours, hypoxia procedure for 1 hour and reperfusion. ANSC was prepared from rats adipose tissue and processed in Laboratory. ANSC was inserted intracerebally after hypoxia procedure and after 48 hours the blood sample were analyzed by using ELISA. T-test for independent samples was used for statistial analysis. There were no significant differences in the TNF-α level between the IR group and IR+ANSC group. There were statistically significant difference in IL-10 level between groups (P&lt; 0.05). Intracerebral ANSC transplantation cannot reduce TNF-α expression and increase IL-10 expression in brain ischemia induced by CCA ligation and hypoxia.