Ischemia-reperfusion Injury Group Research Articles

Assessment of Ankaferd Blood Stopper in experimental liver ischemia reperfusion injury

Background/aim To investigate possible protective effects of Ankaferd Blood Stopper® (ABS) in an experimental liver ischemia reperfusion injury (IRI) model. Materials and methods The study was carried out on 30 female rats separated into 3 groups as sham, control (IRI), and treatment (IRI + ABS) groups. In the IRI + ABS group, 0.5 mL/day ABS was given for 7 days before surgery. In the IRI and IRI + ABS groups, the hepatic pedicle was clamped for 30 min to apply ischemia. Then, after opening the clamp, 90-min reperfusion of the liver was provided. Blood and liver tissue samples were taken for biochemical and histopathological analyses.Results Compared to the sham group, the IRI group had significantly higher levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total oxidant status (TOS), malondialdehyde (MDA), fluorescent oxidant products (FOP) and lower expression of albumin and total antioxidant status (TAS) (P < 0.05). Compared to the IRI group, the IRI+ABS group showed lower expression of AST, ALT, TOS, MDA and FOP and higher expression of albumin and TAS (P < 0.05). In the histopathological analysis, congestion scores were statistically significantly lower in the IRI + ABS group than in the IRI group.ConclusionsABS has a strong hepatoprotective effect due to its antioxidant and antiinflammatory effects and could therefore be used as a potential therapeutic agent for IRI.

Macelignan protects against renal ischemia-reperfusion injury via inhibition of inflammation and apoptosis of renal epithelial cells

Ischemia-reperfusion injury(IRI) refers to tissuedamagethat occurs when blood supply returns to tissue after a period of ischemia,anoxia or hypoxia. It occurs frequently during shock, organ transplantation and heart failure. It can cause impairment or even renal failure. Macelignan is a lignin isolated from the seeds of Myristica fragrans. It has been reported to inhibit neuroinflammation and oxidative toxicity. The preventive or therapeutic effects of macelignan on renal IRI has not been reported. The present study investigated the effects of macelignan on renal IRI in rats, and the underlying mechanism(s). Healthy adult male Sprague Dawley rats (n = 50) aged 7 - 9 weeks (mean weight = 220 ± 20 g) were used in this study. The rats were randomly assigned to five groups of 10 rats each: sham treated group, IRI group and 40 mg macelignan/kg body weight (bwt) group, 80 mg macelignan/kg bwt group, and 160 mg macelignan/kg bwt group. Ischemia-reperfusion injurywas induced in the rats using standard procedure. The results showed that serum levels of creatinine, blood urea nitrogen (BUN), interleukin-6 (IL-6), tumor necrosis factor α (TNF-α) and gamma interferon (IFN-γ) were significantly higher in IRI group than in sham treated group, but were significantly and dose-dependently reduced after treatment with macelignan (p &lt; 0.05). The activities of catalase and superoxide dismutase (SOD), and reduced glutathione (GSH) level were significantly reduced in IRI group, when compared with sham treated group, but were significantly and dose-dependently increased after treatment with macelignan (p &lt; 0.05). However, the level of malondialdehyde (MDA) was significantly higher in IRI group than in sham treated group, but treatment with macelignan reduced it significantly and dose-dependently (p &lt; 0.05). Macelignan also significantly and dose-dependently inhibited IRI-induced apoptosis in epithelial cells of renal tubules (p &lt; 0.05). The results of Western blotting showed that IRI significantly upregulated the expressions of bax and caspase-3, and down-regulated the expression of bcl-2 in epithelial cells of renal tubules (p &lt; 0.05). However, treatment with macelignan significantly and dose-dependently down-regulated the expressions of bax and caspase-3 in these cells, but significantly and dose-dependently upregulated the expression of bcl-2. These results show that macelignan confers protection on renal IRI via mechanisms involving inhibition of inflammation and apoptosis, and stimulation of natural antioxidant defense system.

PD22-04 ORAL ADMINISTRATION OF NANO-SIZED SILICON PARTICLES REGULATES GENE EXPRESSION RELATED TO OXIDATIVE STRESS AND SUPPRESSES RAT RENAL ISCHEMIA-REPERFUSION INJURY

You have accessJournal of UrologyTransplantation & Vascular Surgery: Renal Transplantation & Vascular Surgery I (PD22)1 Apr 2020PD22-04 ORAL ADMINISTRATION OF NANO-SIZED SILICON PARTICLES REGULATES GENE EXPRESSION RELATED TO OXIDATIVE STRESS AND SUPPRESSES RAT RENAL ISCHEMIA-REPERFUSION INJURY Masataka Kawamrua*, Ryoichi Imamura, Yuki Kobayashi, Ayumu Taniguchi, Shigeaki Nakazawa, Taigo Kato, Toyofumi Abe, Hikaru Kobayashi, and Norio Nonomura Masataka Kawamrua*Masataka Kawamrua* More articles by this author , Ryoichi ImamuraRyoichi Imamura More articles by this author , Yuki KobayashiYuki Kobayashi More articles by this author , Ayumu TaniguchiAyumu Taniguchi More articles by this author , Shigeaki NakazawaShigeaki Nakazawa More articles by this author , Taigo KatoTaigo Kato More articles by this author , Toyofumi AbeToyofumi Abe More articles by this author , Hikaru KobayashiHikaru Kobayashi More articles by this author , and Norio NonomuraNorio Nonomura More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000872.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Organ ischemia reperfusion injury (IRI) is unavoidable in kidney transplantation and induces reactive oxygen species and causes organ damage. Although the effectiveness of hydrogen for IRI has been reported for a long time, oral ingestion of hydrogen water and inhalation of hydrogen gas are difficult to apply widely in terms of efficiency and general use. We succeeded in generating a large amount of hydrogen by crushing silicon to nano-sized particle and reacting with water. A silicone component agent was administered to a rat model of renal IRI to examine whether renal injury could be suppressed. METHODS: Six-week-old male SD rats were administered a silicon component feed containing 1% nano-sized silicon particles and IRI surgery was performed one week later. This group was made into a silicon component group (IRI + Si group). An IRI group that administers normal diet and performs IRI surgery and a sham group that performs only right nephrectomy were prepared, and each group was compared 72 hours after surgery. RESULTS: Serum creatinine levels and urine protein significantly decreased in the IRI + Si group,compared to the IRI group. Serum malondialdehyde and urinary 8-hydroxydeoxyguanosine, which are oxidative stress markers, were also significantly decreased in the IRI + Si group. Transcriptome analysis by microarray showed that in the IRI + Si group, the expression of genes related to immune response, cytokine production, and apoptotic signal was decreased in comparison with the IRI group. Furthermore, suppression of mRNA expression level of inflammatory cytokines by quantitative PCR and reduction of renal tubular epithelial cell apoptosis by immunohistochemical evaluation were obtained, suggesting anti-inflammatory and anti-apoptotic effects. CONCLUSIONS: Rat renal IRI was suppressed by oral administration of nano-sized silicon particles, which is a novel hydrogen administration method. Source of Funding: This research was supported by Grants-in-aid for Scientific Research (18K16697) and Center of Innovation Science and Technology based Radical Innovation and Entrepreneurship Program (COI STREAM). © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e460-e460 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Masataka Kawamrua* More articles by this author Ryoichi Imamura More articles by this author Yuki Kobayashi More articles by this author Ayumu Taniguchi More articles by this author Shigeaki Nakazawa More articles by this author Taigo Kato More articles by this author Toyofumi Abe More articles by this author Hikaru Kobayashi More articles by this author Norio Nonomura More articles by this author Expand All Advertisement PDF downloadLoading ...

Protective effects of rosiglitazone on renal ischemia-reperfusion injury in rats

Objective To explore the protective effect and potential mechanism of rosiglitazone(RGZ)on renal ischemia reperfusion injury. Methods Sixty male SD rats were randomly divided in to sham, kidney ischemia reperfusion injury(IRI), RGZ(10 mg/kg) , RGZ(20 mg/kg), RGZ(40 mg/kg) and RGZ(80 mg/kg)groups(n=10). The model of IRI was induced by clamping the bilateral renal pedicles.ELISA was used to examine the expression of Cr, BUN, IL-8, TNF-α and IL-6 in the serum. RT-PCR was used to detect the mRNA level of IL-8, TNF- and IL-6 in the kidney. The activation of CAT, GPX and SOD were mesaured by xanthine oxidase.The expression of PPAR-γ and p-PPAR-γ were measured by Western blot. The expression of MDA was detected by TBA.The kidney pathological morphology was measured by PAS. Results Compared with the sham group, the kidney pathological injury and the expression of Cr, BUN, IL-8, TNF-α, IL-6, p-PPAR-γ and MDA in the IRI group were significantly increased with decreasing the activation of CAT, GPX and SOD. Compared with the IRI group, the kidney pathological injury and the expression of Cr, BUN, IL-8, TNF-α, IL-6, p-PPAR-γ and MDA in the RGZ group were significantly decreased with increasing the expression of p-PPAR-γ and the activation of CAT, GPX and SOD. There was no difference on the expression of PPAR-γ between three groups. Conclusions RGZ pretreatment can protect rats againest kidney ischemia-reperfusion injury. The mechanism of which is associated with suppressing inflammation and oxidative stress by activating PPAR-γ. Key words: Models, Animal; Rats; Reperfusion Injury; Kidney; Rosiglitazone

Impact of Prolonged Mechanical Ventilation on Ferroptosis in Renal Ischemia/Reperfusion Injury in Rats.

We here investigated the impact of mechanical ventilation (MV) time on ferroptosis in a rat renal ischemia/reperfusion injury (IRI) model. Thirty-two male adult Sprague Dawley rats were divided into four groups (n = 8/group): the sham group, IRI group, IRI+MV-4 h group, and IRI+MV-12 h group. Rats in the IRI group were subjected to 45 min bilateral renal ischemia. Rats in the IRI+MV groups were additionally mechanically ventilated with tracheal intubation after 45 min bilateral renal ischemia. Morphological changes associated with kidney injury and ferroptosis were assessed by hematoxylin and eosin staining and electron microscopy. Levels of the central regulator of ferroptosis, glutathione peroxidase 4 (GPX4), and lipid peroxidation markers 4-hydroxynonenal (4HNE) and superoxide dismutase 2 (SOD2) were determined in the kidney tissue by western blotting. Glutathione (GSH) levels were assessed in the serum and kidney homogenate. Scr levels in the IRI+MV-12 h group were significantly higher than those in the sham, IRI, and IRI+MV-4 h groups (all P < 0.001). Electron microscopy revealed the most pronouncedly abnormal mitochondrial morphology, suggestive of ferroptosis, in the IRI+MV-12 h group. The GPX4 and SOD2 protein levels progressively decreased in the following order: sham group > IRI group > IRI+MV-4 h group > IRI+MV-12 h group (P < 0.05 for all comparisons). By contrast, the 4HNE levels progressively increased in the kidney, with the highest values in the IRI+MV-12 h group (P < 0.05, vs. the IRI group and vs. the IRI+MV-4 h group). Further, the GSH levels in the serum and kidney homogenates were significantly reduced in the IRI+MV-12 h group (P < 0.01, vs. IRI group and vs. the IRI+MV-4 h group). A significant positive correlation was observed between the serum and kidney GSH levels (r2 = 0.542, P = 0.03). These observations suggested that prolonged MV may exacerbate renal function failure, already initiated by IRI, by ferroptosis. Depletion of GSH may contribute to this effect, which requires further investigation.

Specific microRNAs are involved in the reno‑protective effects of sevoflurane preconditioning and ischemic preconditioning against ischemia reperfusion injury in rats.

The kidneys are prone to developing ischemia reperfusion injury (IRI) following certain renal surgeries and cardiovascular surgeries requiring cardiac arrest. Sevoflurane and ischemic preconditioning reportedly alleviate IRI, which is mediated via microRNAs. The present study compared anesthetic preconditioning (APC) and ischemic preconditioning (IPC) on microRNAs, which promote cell-survival pathways in rats in a randomized controlled study. After undergoing right nephrectomy under general anesthesia, male Wistar rats (336±24 g) and were divided into four groups (IRI, APC, IPC and sham; n=7 each). The IRI group underwent 45 min clamping of the left renal vasculature, followed by 4 h of reperfusion. APC involved exposure to one minimum alveolar concentration sevoflurane for 15 min. IPC included three cycles of two-min clamping and five-min reperfusion. Blood and renal biopsy samples were assessed postoperatively to measure serum creatinine and to analyze renal microRNA (miR) expression using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) testing and their target pathways with Ingenuity Pathway Analysis™. The present study found that serum creatinine values in APC (0.71±0.08 mg/dl) and IPC (0.73±0.1 mg/dl) groups were lower than in the IRI group (0.96±0.13 mg/dl; P<0.05), indicating amelioration of IRI by APC and IPC. RT-qPCR followed by pathway analysis indicated that APC and IPC affect 'protein kinase B (Akt)'. APC promoted miR-17-3p and suppressed miR-27a. IPC promoted miR-19a. All the miRs were predicted to regulate phosphorylated Akt, which promotes cell-protection. Western blot analysis showed that expression of phosphorylated Akt increased and phosphatase and tensin homologue deleted from chromosome 10 (PTEN) decreased following APC and IPC. The present study concluded that APC and IPC affect different miRs, although they are estimated to similarly promote the PTEN/phosphoinositide 3-kinase/Akt signaling pathway, resulting in reno-protection.

Remote Ischemic Preconditioning Ameliorates Renal Fibrosis After Ischemia-Reperfusion Injury via Transforming Growth Factor beta1 (TGF-β1) Signalling Pathway in Rats.

BackgroundThe present study was conducted to explore the influence of remote ischemic preconditioning (RIPC) on the adjustment of renal fibrosis after ischemia-reperfusion injury (IRI).Material/MethodsMale Sprague-Dawley rats were randomly assigned to 3 groups following right-side nephrectomy: the Sham group (without renal artery clamping), the IRI group (45 min left renal artery clamping), and the RIPC group (rats were treated daily with 3 cycles of 5 min of limb ischemia and 5 min of reperfusion on 3 consecutive days before left renal artery occlusion). After 3 months of reperfusion, the renal function and the extent of tubular injury and renal fibrosis were assessed. The expressions of transforming growth factor beta1 (TGF-β1), p-Smad2, Smad2, p-Smad3, and Smad3 were also evaluated.ResultsThere was no significant difference in renal function and tubular damage among the 3 groups after 45 min of kidney ischemia followed by 3 months of reperfusion. However, an obvious increase of extracellular matrix components and α-SMA could be observed in the kidney tissues of the IRI group, and the changes were significantly ameliorated in rats treated with enhanced RIPC. Compared with the IRI group, the expression of TGF-β1 and the level of p-Smad2 and p-Smad3 were decreased after the intervention of enhanced RIPC.ConclusionsEnhanced RIPC ameliorated renal fibrosis after IRI in rats, which appears to be associated with inhibition of the TGF-β1/p-Smad2/3 signalling pathway.

Protective effects of autophagy inhibitor 3-methyladenine on ischemia-reperfusion-induced retinal injury.

To investigate the protective effects of autophagy inhibitor 3-methyladenine (3-MA) in a rat model of ischemic-reperfusion injury (IRI). Forty Sprague-Dawley male rats (weight 220-250g) were randomly divided into four groups: a control group (NC, n = 10), a Sham surgery group (n = 10), an IRI group (n = 10), and a 3-MA-treated IRI group [10 μL 3-MA (10mmol/L) was injected in vitreous after the injury, n = 10]. The retinal IRI was induced by elevating the intraocular pressure to 110mmHg for 60min. Hematoxylin and eosin (HE) staining was used to calculate the number of retinal ganglion cells (RGCs). The level of microtubule-associated protein 1A/1B light chain 3 (LC3), Beclin-1, and Caspase-3 in the retina was detected using the immunofluorescence staining method. The LC3, Beclin-1, B-cell lymphoma/leukemia-2 (Bcl-2), and Caspase-3 protein levels were examined by Western blotting. The number of RGCs in IRI group was significantly lower than that in NC group (P < 0.05), demonstrated by HE staining. Western blotting results indicated that the protein expression of LC3 and Beclin-1 in the IRI group was significantly elevated compared with those in the NC group (P < 0.05). However, with 3-MA treatment, the number of RCGs in 3-MA-treated IRI group was elevated and protein levels of LC3, Beclin-1 were down-regulated, compared with those in the IRI group (P < 0.05). Further immunohistochemistry staining and Western blot showed that 3-MA-treated IRI group presented down-regulated Caspase-3 and up-regulated Bcl-2 protein expression with comparison of IRI group (P < 0.05). Retina IRI-caused RGCs loss involved activated autophagy pathway and apoptosis, which could be prevented by autophagy inhibitor 3-MA. Autophagy inhibitor 3-MA may act as a potent therapeutic tool in attenuating retina IRI.

Glutamine protects myocardial ischemia-reperfusion injury in rats through the PI3K/Akt signaling pathway.

To study the protective mechanism of glutamine (Gln) on myocardial ischemia-reperfusion (IR) injury in rats through the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. A total of 30 healthy SD rats weighing 200-300 g were used in this experiment. They were randomly divided into 3 groups: sham group (n=10), myocardial IR injury group (IR group, n=10), IR+Gln group (n=10). The protein expression levels of phosphorylated Akt (p-Akt), total Akt (t-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), mTOR, proliferating cell nuclear antigen (PCNA), P21, and Tubulin were determined by Western blotting (WB). Quantitative Polymerase Chain Reaction (qPCR) was applied to detect the messenger ribonucleic acid (mRNA) levels of Akt and mTOR. 3-(4,5)-dimethylthiazol(-z-y1)-3,5-diphenyl tetrazolium bromide (MTT) test was utilized to examine the proliferation ability of cardiomyocytes in vitro. Besides, the contents of the inflammatory cytokines, tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) were measured via enzyme-linked immunosorbent assay (ELISA). Cell apoptosis in each group was examined through Hoechst staining. Compared with those in the sham group, ratios of p-AKT/AKT, p-mTOR/mTOR, and the level of PCNA extremely significantly decreased, but the level of P21 notably increased in IR group (p<0.01). In comparison with those in the IR group, ratios of p-AKT/AKT, p-mTOR/mTOR, and the level of PCNA were remarkably raised, while the level of P21 was remarkably reduced in IR+Gln group (p<0.05). QRT-PCR results manifested that there were no significant differences in the mRNA levels of Akt and mTOR among the three groups [no significant difference (NS)]. Moreover, the cell proliferation ability in IR group was remarkably lower than that in the sham group (p<0.01), while it was enhanced in the IR+Gln group compared with that in the IR group (p<0.05). Additionally, IR group had significantly elevated expression levels of TNF-α and IL-6 compared with the sham group (p<0.01), whereas the IR+Gln group had notably decreased expression levels of TNF-α and IL-6 compared with IR group (p<0.05). In comparison with that in the sham group, the apoptosis in IR group was significantly raised (p<0.01), and compared with that in the IR group, the apoptosis in the IR+Gln group prominently decreased (p<0.05). The contents of the inflammatory cytokines, TNF-α, and IL-6 presented the same trends among the three groups. Gln activates the PI3K/Akt signaling pathway by increasing the levels of p-AKT and p-mTOR. Gln can increase the PCNA level and reduce the P21 level, so as to enhance the proliferation ability of cardiomyocytes. Besides, Gln reduces the levels of inflammatory cytokines, TNF-α, and IL-6, and inhibits cell apoptosis. Finally, Gln can protect cells from myocardial IR injury by activating the PI3K/Akt signaling pathway.

Protective effects of 2-methoxycinnamaldehyde an active ingredients of Cinnamomum cassia on warm hepatic ischemia reperfusion injury in rat model.

Objective(s):Hepatic ischemia/reperfusion injury (IRI) is one of the major causes of hepatic failure during liver transplantation, trauma, and infections. The present study investigated the protective effect of intra-portal administration of 2-methoxycinnamaldehyde (2-MCA) on hepatic IRI in rats. Materials and Methods:Twenty-four rats were equally divided into four groups; 1) sham group, (no IRI or transfusion), 2) Hepatic IRI (60 min ischemia + 120 min reperfusion, 3) Hepatic IRI+ NS (IRI + normal saline), 4) Hepatic IRI+2-MCA, (IRI + 2-MCA). In groups 3 and 4, 1 ml/kg normal saline and 2-MCA were administered slowly into the vein of the left lateral and median lobes of the liver 10 min before induction of hepatic reperfusion (upper the site of clumping), respectively. The harvest time points were at 2 hours post-reperfusion in all groups. Results:Histologically, cell death, degenerative changes, sinusoidal dilatation, congestion, hemorrhage, and infiltration of inflammatory cells were observed in IRI group, while these pathological changes were attenuated in the 2-MCA administrated group. The level of alanine transaminase, aspartate transaminase, tumor necrosis factor- α and interleukin-6 in serum and hepatic malondialdehyde were significantly increased by IRI, and 2-MCA administration reduced all these markers. In addition, caspase-3 and nuclear factor κB (NF-κB) expression were investigated immunohistochemically. Administration of 2-MCA considerably decreased caspase-3 positive cells and NF-κB activity in comparison with IRI group. Conclusion:As a conclusion, in situ administration of 2-MCA protects against hepatic IRI via anti-inflammatory, and anti-apoptotic properties.

Biochemical Studies of Extract of Rosmarinus Officinal is on Oxidative Stress Induced Cerebral Ischemic

Ischemic stroke may happen in different combinations of clinical ailments and these residues represent a major problem. Reactive oxygen species (ROS) have been shown to act a main action in cerebral ischemia reperfusion injury (IRI). Where reperfusion is defined as the action of restoring the flow of blood to an organ or tissue after a heart attack or stroke. Diverse therapeutic effects have been substantive for Rosmarinus Officinalis (Rosemary). In addition to, it has been offered that Rosmarinus Officinalis has covering impact versus I/R stimulate cerebral damages to diverse organs. For this cause, it sounds conceivable that the administration of Rosmarinus Officinalis might keep the brain versus the ischemia reperfusion injury. The study included knowledge the chemical components of the Rosmarinus Officinalis leaves in the watery extract and determine whether Rosmarinus Officinalis prevents ischemia-reperfusion induced stroke. Thirty rats were divided into three groups as control Group 1, IRI group Group2, and Rosmarinus Officinalis treatment group Group3. All animals underwent stroke for 30 min followed by 60 min period of reperfusion. Animals were internal infused with only 0.9% saline solution in group 2. Rats in group3 received Rosmarinus Officinalis (1 mL/kg) for two weeks with the same diet intraperitoneally, before ischemia and before reperfusion. We were the estimation of the biochemical parameters: Blood samples were taken from the rats. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) oxidative stress levels of nitric oxide (NO) and lipid peroxidation (LPO)and blood was used for the estimation of enzyme immunoassay: Interleukin-8 (IL-8), tumor necrosis factor Alpha (TNF-α), interleukin-1β (IL-1β). The results showed that the extract contains several species. The levels of enzymes and Oxidative stress in group3 were significantly lower than those in the group2. Our results suggest thatRosmarinus Officinalis treatment protects the rat brain against ischemia-reperfusion induced Cerebral injuries.

Exosomes Derived From Mesenchymal Stem Cells Ameliorate Renal Ischemic-Reperfusion Injury Through Inhibiting Inflammation and Cell Apoptosis.

This study aimed to investigate the underlying mechanism of mesenchymal stem cells (MSCs) on protection of renal ischemia reperfusion injury (IRI). Exosomes originated from MSCs (MSC-ex) were extracted according to the instructions of Total Exosome Isolation Reagent. Rats were divided into five groups: sham-operated, IRI, MSC, MSC-ex, and MSC-ex + RNAase group. MSCs or MSC-ex were injected via carotid artery. The renal function test and pathological detection were applied to determine the renoprotection of MSC-ex on IRI. Western blotting and quantitative reverse transcription polymerase chain reaction (RT-qPCR) were conducted to examine the levels of apoptosis-related proteins and inflammatory cytokines. Our results revealed that MSC-derived exosomes attenuated renal dysfunction, histologic damage, and decreased apoptosis. The expression levels of inflammatory cytokines, such as interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), nuclear factor kappa B (NF-κB), and interferon gamma (IFN-γ), were decreased by the MSC-ex treatment. The expression levels of caspase-9, cleaved caspase-3, Bax, and Bcl-2 caused by IR were also inhibited by MSC-ex. MSC-ex + RNAase group shared the similar pattern of changes with IRI group, likely due to the ability of RNA hydrolase to eliminate the function of exosomes. Our results demonstrated that exosomes originating from MSCs have protective effects on IRI via inhibiting cell apoptosis and inflammatory responses. Out findings may provide a new insight into therapeutic mechanism of MSCs on renal IRI.

Gadolinium chloride alleviates partial warm ischemia-reperfusion injury of liver by suppressing kupffer cell function in mice

Objective To investigate the effect and mechanism of gadolinium chloride alleviates partial warm ischemia-reperfusion injury of liver by suppressing kupffer cell function in mice. Methods Forty-eight male C57BL/6 mice were randomly divided into sham-operated group (Sham), Hepatic ischemia-reperfusion injury (HIRI) group, gdolinium chloride groups (Gd+ IRI), and cobalt protoporphyrin (CoPP+ IRI) group (n=12). The rats were injected with the same dose of normal saline in Sham group and IRI group. Gd+ IRI group were intraperitoneally injected with GdCl3 (20 mg/kg) 24 hours before operation. At the same time, CoPP+ IRI group were intraperitoneally injected with CoPP (5 mg/kg). Except for Sham group, an 70% volume HIRI model was established by means of 60 minutes ischemia and then 6 hours reperfusion in the other groups. The levels of serum aspartate transaminase (AST) and alanine aminotransferase (ALT) in each group were compared. Enzyme-linked immunosorbent assay were used to test the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in the liver tissue. The level of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, heme oxygenase-1 (HO-1), and protective factor IL-10 mRNA level were detected by real time quantitative polymerase Chain Reaction (RT-PCR). Immunohistochemical staining was used to measure Fas, FasL protein expression level of extrahepatic biliary epithelial cells. Results Respectively, the serum ALT level in the HIRI, Gd+ IRI and CoPP+ IRI groups was (1 236.7±62.4), (638.9±50.9), (740.3±53.1) U/L, and the AST level was (1 107.8±68.3), (568.5±42.7), (679.1±49.9) U/L, the serum level of ALT and AST in Gd+ IRI and CoPP+ IRI groups was lower than IRI group (t=6.721, P<0.01; t=4.732, P<0.05; t=5.984, P<0.01; t=2.691, P<0.05). Compared with IRI group, the activity of SOD and GSH-Px was promoted (t=7.301, P<0.01; t=1.937, P<0.05), whereas the levels of MDA was reduced (t=9.519, P<0.01; t=8.635, P<0.01). Simultaneously, the TNF-α, IL-1β and IL-6 mRNA level in Gd+ IRI and CoPP+ IRI groups were decreased (t=6.721, P<0.01; t=2.316, P<0.05), and the levels of IL-10 and HO-1 mRNA were increased (t=2.973, P<0.05; t=7.921, P<0.01). After hepatic artery reflow 6 h, the Fas expression levels on bile ducts epithelial cells in Gd+ IRI and CoPP+ IRI groups respectively was 22.4%, 29.7%, which was lower than IRI group (38.9%) (χ2=6.561, P<0.01; χ2=2.547, P<0.05). The FasL expression levels in Gd+ IRI and CoPP+ IRI groups respectively was 21.2%, 25.1%, which was lower than IRI group (36.5%) (χ2=5.982, P<0.05; χ2=3.188, P<0.05). Conclusion Gdolinium chloride shows an protective function aganist liver ischemia-reperfusion iniury in mice by Oxidative stress, inhibiting inflammation and cell apoptosis. The up-regulation of HO-1 by gdolinium chloride may be the possible mechanism. The up-regulation of HO-1 and inhibiting the Fas/FasL protein expression by gdolinium chloride may be the possible mechanism. Key words: Gdolinium chloride; Liver; Ischemia-reperfusion injury; Heme oxygenase-l

Alamandine protects rat from myocardial ischemia-reperfusion injury by activating JNK and inhibiting NF-κB.

The aim of this study was to investigate whether alamandine plays a protective role in myocardial ischemia-reperfusion injury (IRI) by activating C-Jun N-terminal kinase (JNK) and inhibiting the expression of key proteins in nuclear factor-kappa B (NF-κB) pathway. Twenty-four Sprague Dawley (SD) rats were numbered and divided into three groups using a random number table, including sham operation group (Sham group), myocardial ischemia-reperfusion injury model group (IRI group), and alamandine pretreatment and myocardial IRI treatment (alamandine group), with 8 SD rats per group. Myocardial tissues were collected from each group. The damage of myocardial tissue was detected using hematoxylin-eosin (H&E) and Masson staining. Finally, the expression levels of JNK and NF-κB pathway-related proteins in myocardial tissue of each group were detected by Western blot. Compared with the IRI group, the alamandine treatment significantly improved cardiac function indicators induced by myocardial IRI in rats, including HR, MAP, LVESP, LVEDP, LVdp/dtmax, and -LVdp/dtmax. In addition, the pathological changes and cell damage of myocardium after alamandine pretreatment were significantly alleviated. At the same time, alamandine can significantly reduce the levels of TNF-α, IL-1β, IL-6, and NO. Finally, Western blot analysis showed that alamandine pre-treatment can protect cardiomyocytes from myocardial IRI by activating JNK phosphorylation and inhibiting the expression of related proteins in the NF-κB signaling pathway. Alamandine can protect rat from myocardial IRI via activating JNK phosphorylation and inhibiting NF-κB signaling pathway to reduce the inflammatory response.

Preconditioning with one-time hydrogen gas does not attenuate skin flap ischemia-reperfusion injury in rat models

Hydrogen gas exists in the atmosphere and was previously considered an inert gas. It has been reported to have protective effects on tissue ischemia-reperfusion (IR) injuries in animal models. The protective mechanism of hydrogen molecules is based on selectively reducing highly strong oxidants in cells, thereby reducing inflammation and decreasing the contents of MDA, FOXO3a, and other pathways that result in flap necrosis. Previous studies were conducted with postconditioning with hydrogen. In this article, we want to investigate whether inhalation of hydrogen has a preventive effect on IR injury. Forty-five adult male Sprague Dawley rats (body weight 220-250 g) were randomly divided into three groups: (1) Sham operation group (SH), (2) Ischemia-reperfusion injury group (IR), and (3) Ischemia-reperfusion injury with preconditioning hydrogen group (PRH). IR injury was induced by clamping the right superficial epigastric artery for 3h. Before undergoing 3h of IR management, the PRH group was treated with hydrogen inhalation for 1 h. On the third postoperative day, survival area and blood perfusion of the flap were assessed using laser Doppler flowmetry. RIP1 and RIP3 were examined by immunological detection and western blot analysis. Both the IR and PRH groups had less skin flap survival area and less blood perfusion than the sham group (P<0.05). RIP1 and RIP3 were highly expressed in the IR and PRH groups when compared with those in the SH group (P<0.05). There were no significant differences in flap survival rate (32.34±2.19% and 33.09±1.64%), average blood perfusion (41.66±3.53pu, 48.57±2.83pu), and expression of RIP1 and RIP3 (0.5167±0.1409 and 0.4693±0.1454) between the IR and PRH groups. Preconditioning with one-time inhaled hydrogen does not attenuate skin flap IR injuries in rat models.

Inverse correlation of kidney interstitial cells expansion with hemoglobin level and erythropoietin expression in single and repeated kidney ischemic/reperfusion injury in mice

Ischemic/reperfusion injury (IRI) causes acute kidney injury that may lead to chronic kidney disease. We investigated the correlation between kidney interstitial cells expansion, hemoglobin level, and erythropoietin expression as the chronic effects of single and repeated kidney IRI in mice. We created an IRI model using male Swiss mice by clamping the bilateral renal pedicles. Subjects were divided into four groups that contained six mice each: control/sham operation, single acute IRI, single chronic IRI, and repeated IRI. Our results showed that the single chronic and repeated IRI groups significantly increased the tubular injury score, decreased the hemoglobin level, and increased erythropoietin expression compared with the control. Lower hemoglobin levels in all of the groups compared with the control was associated with erythropoietin resistance. In single chronic and repeated kidney IRI, there were decreased creatinine levels compared with the control. The decreased creatinine levels from the single acute IRI group to the single chronic IRI group, suggesting a repair phase of IRI starting on day 7 occurred in the single chronic IRI group. A macrophage marker, CD68, and an inflammatory mediator marker, MCP-1, significantly increased in all IR groups, indicating inflammation occurred due to IRI. In conclusion, chronic and repeated kidney IRI induced interstitial cells expansion and inflammation associated with anemia.

Chronic intermittent hypobaric hypoxia attenuates skeletal muscle ischemia-reperfusion injury in mice

AimThe aim of this study was to investigate the protective effect of chronic intermittent hypobaric hypoxia (CIHH) against skeletal muscle ischemia-reperfusion (IR) injury and to determine the underlying mechanism. Main methodsC57BL/6 mice were randomly divided into 3 groups: skeletal muscle IR injury group (IR), CIHH pretreatment following IR group (IR + CIHH), and sham operation group (Sham). The skeletal muscle IR injury model was induced by the unilateral application of a tourniquet on a hind limb for 3 h and then releasing it for 24 h. CIHH pretreatment simulating a 5000-m altitude was applied 6 h per day for 28 days. The functional and morphological performance of IR-injured gastrocnemius muscle was evaluated using contraction force, H&E staining, and transmission electron microscopy. IR injury-induced CD68+ macrophage infiltration was assessed by immunofluorescence. TNFα levels in serum and muscle were measured by ELISA and western blotting, respectively. Apoptosis was examined by TUNEL staining and Cleaved Caspase-3 protein expression. Key findingsAcute IR injury resulted in reduced contraction tension, morphological destruction, macrophage infiltration, increased TNFα levels, and apoptosis in gastrocnemius muscle. CIHH pretreatment significantly ameliorated contraction function and morphological performance in IR-injured skeletal muscle. In addition, CIHH pretreatment resulted in marked decreases in CD68+ macrophage infiltration, TNFα levels, and apoptosis. SignificanceThese data demonstrated that CIHH has a protective effect against acute IR injury in skeletal muscle via inhibition of inflammation and apoptosis.

22-oxacalcitriol protects myocardial ischemia-reperfusion injury by suppressing NF-κB/TNF-α pathway.

The aim of this study was to explore whether 22-oxacalcitriol could protect inflammatory response induced by ischemia-reperfusion injury (IRI) in rats, and to investigate its underlying mechanism. 24 male Sprague Dawley rats were randomly assigned into the sham group, the IRI group and the 22-oxacalcitriol group, with 8 rats in each group. Serum and heart samples of each rat were collected 10 days after the animal procedure. The serum levels of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) in each rat were detected by relative commercial kits. Pathological lesions in rat myocardium were observed by hematoxylin and eosin (HE) staining. Cardiomyocyte apoptosis in rat heart was accessed by TUNEL staining. Meanwhile, the serum levels of tumor necrosis factor-α (TNF-α), interleukin 1 beta (IL-1β), interleukin-6 (IL-6), and KC-GRO were detected by Real Time-quantitative Polymerase Chain Reaction (RT-qPCR). Also, the protein expression levels of NF-κB, TNF-α, VCAM-1, ICAM-1, and MCP-1 in rat myocardium were detected by Western blot and immunohistochemistry. The serum levels of CK-MB and LDH in rats of the IRI group were significantly higher than those of the sham group. 22-oxacalcitriol treatment remarkably decreased the serum levels of CK-MB and LDH when compared with the IRI group. However, cardiomyocyte apoptosis of the 22-oxacalcitriol group was markedly less than the IRI group. The activities of SOD, GSH, CAT and T-AOC in the cardiac homogenate of the 22-oxacalcitriol group were significantly elevated than those of the IRI group. Meanwhile, malondialdehyde (MDA) and reactive oxygen species (ROS) levels were remarkably decreased by 22-oxacalcitriol treatment. Furthermore, the serum levels of TNF-α, IL-1β, IL-6 and KC-GRO were significantly downregulated in the 22-oxacalcitriol group. Western blot results showed that the protein expression levels of NF-κB, TNF-α, VCAM-1, ICAM-1 and MCP-1 in the 22-oxacalcitriol group were significantly lower than those of the IRI group. 22-oxacalcitriol inhibits the inflammatory response in the myocardium by suppressing NF-kB/TNF-α pathway, thereby protecting myocardial ischemia-reperfusion injury in rats.

Heat Shock Protein 70 Messenger RNA in Rat Leukocytes Elevates After Severe Intestinal Ischemia–Reperfusion

BackgroundHeat shock protein 70 (HSP70) confers protection against heat shock, oxidative stress, infection, and inflammation in many cell types. A recent study reported that the induction of HSP70 was associated with morphologic protection against ischemia–reperfusion injury (IRI) in the rat small intestine. This study investigated the dynamics of HSP70 in leukocytes during intestinal IRI in a rat model. Materials and methodsSerial blood samples were collected at 60-minute intervals up to 240 min from male Wistar rats (n = 15). The rats were divided into three groups of five each: the control group, the nonlethal IRI group, and the lethal IRI group. Rats belonging to the control group underwent a sham operation, and laparotomy was performed on rats in the lethal and nonlethal IRI groups. The nonlethal group experienced a 30-minute clamping of the superior mesenteric artery, and the lethal group experienced a 75-minute clamping of the superior mesenteric artery. The expression of HSP70 messenger RNA (mRNA) in leukocytes was measured by real-time quantitative polymerase chain reaction. Mixed-effects modeling of repeated measures was used to carry out the statistical analysis. The Bonferroni correction was applied to multiple comparisons. A P value < 0.0167 was considered to indicate statistical significance. ResultsThe expression of HSP70 mRNA in leukocytes increased 60 min after reperfusion in both IRI groups, and it was 12.8 times higher in the lethal group and 3.6 times higher in the nonlethal group compared with the control group. The expression of mRNA in the lethal group was significantly increased compared with the nonlethal group and the control group at 120 and 180 min after reperfusion. At 120 min after reperfusion, the expression of HSP70 mRNA was 6.1 times higher in the lethal group than in the nonlethal group (P = 0.0075) and 17.7 times higher than in the control group (P = 0.0011). At 180 min after reperfusion, the expression of HSP70 mRNA was 6.8 times higher in the lethal group than in the nonlethal group (P = 0.0007) and 4.3 times higher than in the control group (P = 0.0032). Although the expression of HSP70 mRNA in the nonlethal group was elevated in the early stages of reperfusion, there was no difference between the nonlethal group and the control group (P = 0.0212 at 60 min). ConclusionsThe expression of HSP70 mRNA in leukocytes may be a clinically useful indicator for evaluating pathologic conditions in intestinal IRI.

Effect of dexmedetomidine on ischemia-reperfusion injury of liver and kidney tissues in experimental diabetes and hepatic ischemia-reperfusion injury induced rats

Background: Reperfusion following ischemia can lead to more injuries than ischemia itself especially in diabetic patients. The aim of this study was to evaluate the effect of dexmedetomidine on ischemia-reperfusion injury (IRI) in rats with have hepatic IRI and diabetes mellitus.