Ischemia-reperfusion Procedure Research Articles

A Comparative Study: Cardioprotective Effects of High-Intensity Interval Training Versus Ischaemic Preconditioning in Rat Myocardial Ischaemia-Reperfusion.

(1) Background: Years of research have identified ischemic preconditioning (IPC) as a crucial endogenous protective mechanism against myocardial ischemia-reperfusion injury, enhancing the myocardial cell's tolerance to subsequent ischemic damage. High-intensity interval training (HIIT) is promoted by athletes because it reduces exercise duration and improves metabolic response and cardiopulmonary function. Our objective was to evaluate and compare whether HIIT and IPC could reduce myocardial ischemia and reperfusion injury in rats. (2) Methods: Male Sprague-Dawley rats were divided into four groups: sham surgery, coronary artery occlusion (CAO), high-intensity interval training (HIIT), and ischemic preconditioning (IPC). The CAO, HIIT, and IPC groups experienced 40 min of coronary artery occlusion followed by 3 h of reperfusion to induce myocardial ischemia-reperfusion injury. Subsequently, the rats were sacrificed, and blood samples along with cardiac tissues were examined. The HIIT group received 4 weeks of training before surgery, and the IPC group underwent preconditioning before the ischemia-reperfusion procedure. (3) Results: The HIIT and IPC interventions significantly reduced the extent of the myocardial infarction size and the levels of serum troponin I and lactate dehydrogenase. Through these two interventions, serum pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-6, were significantly decreased, while the anti-inflammatory cytokine IL-10 was increased. Furthermore, the expression of pro-apoptotic proteins PTEN, caspase-3, TNF-α, and Bax in the myocardium was reduced, and the expression of anti-apoptotic B-cell lymphoma 2 (Bcl-2) was increased, ultimately reducing cellular apoptosis in the myocardium. In conclusion, both HIIT and IPC demonstrated effective strategies with potential for mitigating myocardial ischemia-reperfusion injury for the heart.

The Effect of Sevoflurane and Fullerenol C 60 on the Liver and Kidney in Lower Extremity Ischemia-Reperfusion Injury in Mice with Streptozocin-Induced Diabetes.

This study aimed to demonstrate whether fullerenol C60, sevoflurane anesthesia, or a combination of both had protective effects on the liver and kidneys in lower extremity ischemia-reperfusion injury (IRI) in mice with streptozocin-induced diabetes. A total of 46 Swiss albino mice were divided into six groups as follows: control group (group C, n=7), diabetes group (group D, n=7), diabetes-ischemia/reperfusion (group DIR, n=8), diabetes-ischemia/reperfusion-fullerenol C60 (group DIR-FC60, n=8), diabetes-ischemia/reperfusion-sevoflurane (group DIR-S, n=8), and the diabetes-ischemia/reperfusion-fullerenol C60-sevoflurane (group DIR-S-FC60, n=8). Fullerenol C60 (100mg/kg) was administered intraperitoneally 30 min before the ischemia-reperfusion procedure to the fullerenol groups (DIR-FC60 and DIR-S-FC60). In the DIR groups, 2 hours (h) ischemia-2h reperfusion periods were performed. In the sevoflurane groups, sevoflurane was applied during the ischemia-reperfusion period with 100% O2. Liver and kidney tissues were removed at the end of the reperfusion procedure for biochemical and histopathological examinations. In liver tissue, hydropic degeneration, sinusoidal dilatation, pycnotic nuclei, prenecrotic cells, and mononuclear cell infiltration in parenchyma were significantly more frequent in group DIR than in groups D and group C. In terms of the histopathologic criteria examined, more positive results were seen in group DIR-FC60, and when group DIR-FC60 was compared with group DIR, the difference was significant. The best results in AST, ALT, glucose, TBARS levels, and SOD enzyme activities in liver tissue were in group DIR-FC60 compared with group DIR, followed by groups DIR-S-FC60 and DIR-S, respectively. Regarding TBARS levels and SOD enzyme activities in kidney tissue, the best results were in groups DIR-FC60, DIR-S-FC60, and DIR-S, respectively. According to our findings, it is clear that fullerenol C60 administered intraperitoneally 30 min before ischemia, alone or together with sevoflurane, reduces oxidative stress in distant organ damage caused by lower extremity IRI, and reduces liver and kidney tissue damage in histopathologic examinations.

Cardiac damage following renal ischemia reperfusion injury increased with excessive consumption of high fat diet but enhanced the cardiac resistance to reperfusion stress in rat

Renal ischemia-reperfusion (IR) injury inflicts remote cardiac dysfunction. Studies on rats fed with a high-fat diet (HD) showed contradictory results: some demonstrated increased sensitivity of the heart and kidney to IR injury, while others reported resistance. In this study, we examined cardiac dysfunction and compromised cardiac tolerance associated with renal IR in HD and standard diet (SD) fed rats. Male Wistar rats fed with HD or SD diet for 16 weeks were subjected to either renal sham or IR protocol (bilateral clamping for 45 min and reperfusion for 24 h). The hearts isolated from these rats were further subjected to normal perfusion or IR procedure to study cardiac response. Renal IR surgery negatively affected cardiac function with substantial changes in the cardiac tissues, like mitochondrial dysfunction, elevated oxidative stress, and inflammation. HD-fed rat hearts exhibited hypertrophy at the end of 16 weeks, and the consequential impact on the heart was higher in the animals underwent renal IR surgery than with sham surgery. However, the IR induction in the isolated heart from renal sham or renal IR operation showed significant tissue injury resistance and better physiological recovery in HD-fed rats. However, in SD-fed rats, only hearts from renal IR-operated rats showed resistance to cardiac IR, whereas hearts from renal sham-operated rats were more susceptible to IR damage. The augmented IR resistance in the heart with prior renal surgery was due to preserved mitochondrial bioenergetics function, reduced oxidative stress, and activation of the PI3K/AKT signaling axis.

High-fat diet-induced mitochondrial dysfunction is associated with loss of protection from ischemic preconditioning in renal ischemia reperfusion.

Consumption of high-fat diet (HFD) promotes mitochondrial dysfunction and the latter act as a critical factor in determining the severity of ischemia-reperfusion (IR) injury in different cell types. Ischemic preconditioning (IPC), a well-known protocol that render IR protection in kidney works via mitochondria. In the present study, we evaluated how HFD kidney with underlying mitochondrial changes respond to precondition protocol after IR induction. Wistar male rats were used in this study and were divided into two groups: SD (standard diet; n = 18) and HFD (high-fat diet; n = 18), which were further subdivided into sham, ischemia-reperfusion, and precondition groups at the end of the dietary regimen. Blood biochemistry, renal injury marker, creatinine clearance (CrCl), mitochondrial quality (fission, fusion, and phagy), mitochondrial function via ETC enzyme activities and respiration, and signalling pathway were analysed. Sixteen weeks of HFD administration to the rat deteriorated the renal mitochondrial health measured via 10% decline in mitochondrial respiration index ADP/O (in GM), reduced mitochondrial copy number (55%), biogenesis (56%), low bioenergetics potential (19% complex I + III and 15% complex II + III), increased oxidative stress, and reduced expression of mitochondrial fusion genes compared with SD rats. IR procedure in HFD rat kidney inflicted significant mitochondrial dysfunction and further deteriorated copy number along with impaired mitophagy and mitochondrial dynamics. IPC could effectively ameliorate the renal ischemia injury in normal rat but failed to provide similar kind of protection in HFD rat kidney. Even though the IR-associated mitochondrial dysfunction in both normal and HFD rats were similar, the magnitude of overall dysfunction and corresponding renal injury and compromised physiology was high in HFD rats. This observation was further confirmed via in vitro protein translation assay in isolated mitochondria from normal and HFD rat kidney that showed significantly reduction in the response ability of mitochondria in HFD. In conclusion, the deteriorated mitochondrial function and its quality along with low mitochondrial copy number and downregulation of mitochondrial dynamic gene exhibited by HFD rat kidney augments the sensitivity of renal tissue towards the IR injury which leads to the compromised protective ability by ischemic preconditioning.

The hepato-renal protective potential of walnut seed skin extract against acute renal ischemia/reperfusion damage

Acute kidney damage is defined as a sudden change in kidney functions that prevents the removal of nitrogenous wastes from the body, thus disrupting the body's fluid and electrolyte balance. When acute kidney injury occurs, the kidneys and liver are most affected in the body. Agents used in the treatment of acute kidney injury often have nonsteroidal anti-inflammatory properties that can produce toxic effects on the gastrointestinal tract and kidneys. Natural antioxidants can be recommended as an alternative to existing treatment or in combination to protect tissues against these toxic effects. Therefore, we conducted our current study on whether walnut seed skin (WSS) extract might have hepato-renal protective effects in kidney-damaged Sprague-Dawley rats. This study is the first to use walnut seed skin extract in liver and kidney tissues in renal ischemia/reperfusion (IR) injury. Female Sprague-Dawley rats were randomly divided into three groups: Healty control (HC), renal IR (50 min ischemia – 3 h reperfusion), and renal IR + 450 mg/kg/p.o. WSS extract (the rats were treated with WSS extract orally once 1 h before the IR procedure). For this purpose, blood, liver and kidney tissues of rats were used. In serum samples, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), urea and creatinine values were determined separately for the administration groups. We also performed histopathological studies on liver and kidney tissues. Finally, gene markers (endothelial nitric oxide synthase (eNOS), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), Caspase-4 and Caspase-9) determined to evaluate the anti-oxidant, anti-inflammatory and apoptotic effect of walnut seed skin were measured by q-RT PCR method. As a result of the study it was determined that pre-application of WSS extract improved the deteriorated serum parameters in rats with renal ischemia. In the histopathological analysis results, it was observed that WSS had a protective effect on kidney and liver tissue. In studies on gene expression, although there were different and contradictory results for liver and kidney tissue, we determined that WSS was more protective on liver tissue. In conclusion, the healing potential of WSS in renal and hepatic tissues seems to act by inhibiting the inflammatory response, oxidative stress and apoptosis. Therefore, the potential of this extract is remarkable and may serve as a potential therapeutic that may protect against acute organ damages due to renal IR.

Abstract 10234: Exaggerated Blood Pressure Response to Static Exercise Following Muscle Ischemia-Reperfusion: A Time-Course Investigation

Background: Peripheral artery disease (PAD) is one of the major cardiovascular concerns and dramatically reduces the blood flow supply in the affected limbs. A combination of revascularization surgery in the femoral artery and supervised exercise intervention is among the most general approaches for the treatment of PAD. However, the effects of ischemia-reperfusion (IR), which is one of the most predominant complications resulting from the revascularization surgery, on exercise-induced arterial blood pressure (BP) response are poorly understood. Methods: We examined the BP response to static muscle contraction in rats at different time points after the IR procedure. Four groups were included: 1. Sham rats; 2. Rats with 18 hours following IR (IR 18h); 3. Rats with 66 hours following IR (IR 66h); 4. Rats with 114 hours following IR (IR 114h). One-way ANOVA with LSD post-hoc test was applied to analyze the difference among groups. Data were presented as Mean ± Standard Deviation. Results: Compared with Sham group, the BP response to static muscle contraction was significantly increased in rats with all the investigated time points. The response of mean arterial pressure was 19±3 mmHg in Sham rats (n=6); 29±9 mmHg in IR 18h rats (n=8); 26±7 mmHg in IR 66h rats (n=10); 26±4 mmHg in IR 114h rats (n=9) ( P <0.05; the groups at three time courses vs. Sham). There was no significant difference observed in the peak developed tension during muscle contraction among all the groups (Sham rats: 543±101g; IR 18h rats: 520±28g; IR 66h rats: 554±66g; IR 114h rats: 562±45g; P >0.05). Conclusions: IR significantly exaggerates the static exercise-induced BP response. Whereas the BP response tends to decrease with the prolonged IR time, the exaggerated BP response remains through time points from post IR 18 hours to 114 hours. The data suggest that a chronic time course should be considered to alleviate IR-induced ischemic injury in PAD patients for clinical interventions appropriated and exercise.

The effects of iloprost and beta3 receptor agonist on TRPA1 and TRPC1 immunreactivity in an experimental lower extremty ischemia-reperfusion injury model.

Background/aim In this study, we aimed to investigate the effects of antioxidant iloprost (ILO) and ß3 adrenergic receptor agonist (BRL) on transient receptor potential ankyrin 1 (TRPA1) and transient receptor potential canonical 1 (TRPC1) ion channels on an experimental ischemia and reperfusion injury model in 30 male Wistar albino rats aged 8–10 weeks.Materials and methodsWistar Albino rats aged were divided into 5 equal groups. Group I Sham operation, Group II IR (ischemia-reperfusion) procedure, Group III IR + intravenous ILO administration, Group IV IR + intraperitoneal BRL administration, and Group V IR + intravenous ILO + intraperitoneal BRL administration group. Two ng/kg/min ILO intravenous infusion was applied to the ILO group. A single dose of 5 mcg/kg BRL intraperitoneal was applied to BRL group. TOS (total oxidant status), TRPA1, and TRPC1 levels were measured with ELISA (enzyme linked immunosorbent assay) in serum, immunohistochemical staining in musculus quadriceps femoris tissue. ResultsCompared with the sham group, the IR group had a statistically significant increase in serum levels of TOS (p = 0.004), TRPA1 (p = 0.002), and TRPC1 (p = 0.008) along with TRPA1- and TRPC1-immunoreactivity (p = 0.005, each) in the tissue. When compared with the IR group in terms of serum levels of TRPA1 and tissue TRPA1-immunoreactivity, although there was no statistically significant difference in the IR+Ilo (p = 0.257 and p = 0.429, respectively), IR+Brl (p = 0.024 and p = 0.177, respectively), and IR+Ilo+Brl (p = 0.024 and p = 0.329, respectively) groups, serum levels of TOS and TRPC1 along with tissue TRPC1-immunoreactivity were statistically significantly reduced in the IR+Ilo (p = 0.002, p = 0.008, and p = 0.004, respectively), IR+Brl (p = 0.004, p = 0.008, and p = 0.004, respectively), and IR+Ilo+Brl groups (p = 0.002, p = 0.008, and p = 0.004, respectively). ConclusionIn IR group serum TOS, TRPA1 and TRPC1 levels ,and tissue TRPA1 and TRPC1 immunoreactivity were statistically significant increase when compared to the sham group. In IR+ILO, IR+BRL and IR+ILO+BRL groups serum TRPA1 and tissue TRPA1 immunoreactivity did not change when compared to IR group. Serum TOS and TRPC1 levels, tissue TRPC1 immunoreactivty were statistically significant decreased when compared to IR group. More detailed and expanded population studies are needed to discuss our results.

Protective Role of Kynurenine 3-Monooxygenase in Allograft Rejection and Tubular Injury in Kidney Transplantation.

Renal tubular epithelial cells (TECs) are the primary targets of ischemia–reperfusion injury (IRI) and rejection by the recipient’s immune response in kidney transplantation (KTx). However, the molecular mechanism of rejection and IRI remains to be identified. Our previous study demonstrated that kynurenine 3-monooxygenase (KMO) and kynureninase were reduced in ischemia–reperfusion procedure and further decreased in rejection allografts among mismatched pig KTx. Herein, we reveal that TEC injury in acutely rejection allografts is associated with alterations of Bcl2 family proteins, reduction of tight junction protein 1 (TJP1), and TEC-specific KMO. Three cytokines, IFNγ, TNFα, and IL1β, reported in our previous investigation were identified as triggers of TEC injury by altering the expression of Bcl2, BID, and TJP1. Allograft rejection and TEC injury were always associated with a dramatic reduction of KMO. 3HK and 3HAA, as direct and downstream products of KMO, effectively protected TEC from injury via increasing expression of Bcl-xL and TJP1. Both 3HK and 3HAA further prevented allograft rejection by inhibiting T cell proliferation and up-regulating aryl hydrocarbon receptor expression. Pig KTx with the administration of DNA nanoparticles (DNP) that induce expression of indoleamine 2,3-dioxygenase (IDO) and KMO to increase 3HK/3HAA showed an improvement of allograft rejection as well as murine skin transplant in IDO knockout mice with the injection of 3HK indicated a dramatic reduction of allograft rejection. Taken together, our data provide strong evidence that reduction of KMO in the graft is a key mediator of allograft rejection and loss. KMO can effectively improve allograft outcome by attenuating allograft rejection and maintaining graft barrier function.

Dendritic Cells: Versatile Players in Renal Transplantation.

Dendritic cells (DCs) induce and regulate adaptive immunity through migrating and maturing in the kidney. In this procedure, they can adopt different phenotypes—rejection-associated DCs promote acute or chronic injury renal grafts while tolerogenic DCs suppress the overwhelmed inflammation preventing damage to renal functionality. All the subsets interact with effector T cells and regulatory T cells (Tregs) stimulated by the ischemia–reperfusion procedure, although the classification corresponding to different effects remains controversial. Thus, in this review, we discuss the origin, maturation, and pathological effects of DCs in the kidney. Then we summarize the roles of divergent DCs in renal transplantation: taking both positive and negative stages in ischemia–reperfusion injury (IRI), switching phenotypes to induce acute or chronic rejection, and orchestrating surface markers for allograft tolerance via alterations in metabolism. In conclusion, we prospect that multidimensional transcriptomic analysis will revolute researches on renal transplantation by addressing the elusive mononuclear phagocyte classification and providing a holistic view of DC ontogeny and subpopulations.

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<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.

Impact of One Versus Two Consecutive Doses of Endothelial Cells (EPCs) and EPCs-Derived Condition Medium on Protecting Myocardium from Acute Ischemia-Reperfusion Injury in Rat

This study tested the impact of single dose and two doses of endothelial progenitor cells (EPCs) and EPCs-derived condition medium (CM) on protecting the left-ventricular myocardium (LVM) from acute ischemia-reperfusion (IR) injury. In vitro study showed EPCs and CM had comparably higher capacity for enhancement of angiogenesis as compared with the controls (all P < .001). Adult-male SD rats (n = 36) were equally categorized into groups 1 (sham-operated control), 2 (IR+vehicle), 3 [IR+EPCs/1.2 × 106/intravenous administration at 3 h after IR procedure), 4 (IR+EPCs/1.2 × 106/at 3 h/24 h after IR), 5 (IR+CM/3.0cc/intravenous administration at 3 h after IR), 6 (IR+EPCs/3.0cc/at 3h/24 h after IR), and euthanized by day 3 after IR. The left-ventricular-ejection-fraction, protein and cellular expressions of endothelial-cell markers (CD31/vWF), small vessel number and protein expression of mitochondrial (mitochondrial-cytochrome-C) integrity were highest in group 1, lowest in group 2, significantly higher in group 4 than in groups 3/5/6 and significantly higher in groups 3/6 than in group 5 but they showed no differences in groups3/6, whereas the protein expressions of apoptotic (cleaved-caspase 3/cleaved-PARP), fibrotic (Smad3/TGF-ß), mitochondrial-damaged (cytosolic-cytochrome-C), heart-failed/pressure-overload (BNP), oxidative-stress (p47phox/NOX-1/NOX-2/oxidized protein), and autophagic (LCB3-II/LCB3-I) biomarkers and fibrotic/collagen-deposition areas exhibited an opposite pattern to endothelial-cell markers (all P < .0001). The protein expressions of angiogenesis (VEGF/SDF-1α/CXCR4/HIF-1α) were lowest in group 1, highest in group 4, significantly higher in groups 3/6 than in groups 2/5, significantly higher in group 5 than in group 2, but they showed no difference between groups 3/6 (all P < .0001). These results demonstrate that two consecutive doses of EPC/CM were superior to just one at protecting LVM against IR injury.

The targets of β-sitosterol as a novel therapeutic against cardio-renal complications in acute renal ischemia/reperfusion damage.

This research is the first to use β-sitosterol on myocardial and renal tissues in renal ischemia/reperfusion (IR) damage. Female Wistar rats were randomly divided into three groups: control (sham), renal IR (50min ischemia - 3h reperfusion), and renal IR + 150mg/kg/p.o. β-sitosterol (the rats were treated with β-sitosterol orally once 1h before the IR procedure). β-Sitosterol pretreatment caused an increase in superoxide dismutase and glutathione activities and a decrease in malondialdehyde levels in the kidney and heart. Moreover, it alleviated histopathological changes and downregulated the levels of tumor necrosis factor-alpha and interleukin-6 and upregulated the levels of endothelial nitric oxide synthase. As conclusion, the potential of β-sitosterol for renal and cardiac necrosis and apoptosis appears to act by limiting inflammatory response and oxidative stress. Thus, the potential of this compound is noteworthy and may serve as a potential therapeutic in the treatment of acute organ damages due to renal IR.

Ratlarda böbrek iskemi-reperfüzyon hasarında proflaktik kalsiyum dobesilatın etkinliği

Aim: In this study, the objective was to investigate the protective effect of calcium dobesilate, which has antioxidant and anti-inflammatory properties, on the experimental renal ischemia-reperfusion injury (IRI). Methods: Twenty-four male Wistar-Albino rats were divided into three groups: Sham group (Group 1), ischemia-reperfusion group (Group 2), and treatment group (Group 3). Before the ischemia-reperfusion procedure, rats in Group 3 received calcium dobesilate through gavage (100mg/kg/day) for 10 days. Groups other than the sham group underwent ischemia for 45 minutes and reperfusion for 24 hours. Plasma urea and creatinine levels, erythrocyte superoxide dismutase and glutathione peroxidase enzyme activity levels were measured. In addition, histopathological changes that may be related to ischemia-reperfusion injury in the renal tissue, were investigated.Results: The median glutathione peroxidase and superoxide dismutase enzyme levels were higher in Group 2 compared to Groups 1 and 3. However, the differences were not statistically significant. The creatine levels were statistically lower in Group 3 compared to Group 1 and Group 2. The median urea levels were lower in Group 3 than in Group 1 and Group 2, but the differences were not statistically significant. The histopathological examination showed that parameters such as cellular necrosis, flattened tubular epithelial cells, cytoplasmic vacuolization, tubular lumen obstruction, and chronic inflammation, which are indicators of the ischemia-reperfusion injury, were statistically less common in the treatment group compared to the control group. Conclusion: Our study demonstrated that prophylactic calcium dobesilate had a protective effect on ischemia-reperfusion injury.

Silibinin treatment results in reducing OPA1&MFN1 genes expression in a rat model hepatic ischemia-reperfusion.

The mitochondrial damage has a pivotal role in triggering apoptosis and cell death. This study assessed the effect of silibinin on optical atrophy-1 (OPA1) and mitofusin-1 (MFN1) gene expression in liver tissue during hepatic warm ischemia-reperfusion (IR). Four groups of rats, eight rats each were designed: Vehicle: the rats received normal saline and encountered to laparotomy, Sili: silibinin (60 mg/kg) was administered to animals, IR: the rats received the normal saline and insulted by liver IR procedure, and IR + Sili: silibinin was injected to rats. All groups were subjected to the same process of injection of the solvent or silibinin (30 min before laparotomy or ischemia and immediately after the reperfusion), intraperitoneally (IP). After 3 h of reperfusion, blood and liver tissue samples were collected for future examinations. Our results showed no significant differences between the Vehicle and Sili groups in all assessed parameters. In IR + Sili, the increased serum levels of AST and ALT in comparison with the control group were markedly reduced by silibinin treatment. Silibinin lowered the elevated expression of OPA1 and MFN1 mRNAs in the IR group. Histology revealed silibinin could decline tissue degeneration compared to the IR group. Electron microscopy of control and silibinin groups showed no fusion of mitochondria and tissue degradation both of which were observed in the IR group. The extent of tissue destruction and mitochondrial fusion decreased significantly with silibinin treatment. Silibinin has a protective effect on liver cells against IR induced injuries by preserving mitochondrial membrane.

Xenogeneic and Allogeneic Mesenchymal Stem Cells Effectively Protect the Lung Against Ischemia-reperfusion Injury Through Downregulating the Inflammatory, Oxidative Stress, and Autophagic Signaling Pathways in Rat

This study tested the hypothesis that both allogenic adipose-derived mesenchymal stem cells (ADMSCs) and human inducible pluripotent stem cell-derived MSCs (iPS-MSCs) offered a comparable effect for protecting the lung against ischemia-reperfusion (IR) injury in rodent through downregulating the inflammatory, oxidative stress, and autophagic signaling pathways. Adult male Sprague–Dawley rats (n = 32) were categorized into group 1 (sham-operated control), group 2 (IRI), group 3 [IRI + ADMSCs (1.0 × 106 cells)/tail-vein administration at 0.5/18/36 h after IR], and group 4 [IRI + iPS-MSCs (1.0 × 106 cells)/tail-vein administration at 0.5/18/36 h after IR], and lungs were harvested at 72 h after IR procedure. In vitro study demonstrated that protein expressions of three signaling pathways in inflammation (TLR4/MyD88/TAK1/IKK/I-κB/NF-κB/Cox-2/TNF-α/IL-1ß), mitochondrial damage/cell apoptosis (cytochrome C/cyclophilin D/DRP1/ASK1/APAF-1/mitochondrial-Bax/caspase3/8/9), and autophagy/cell death (ULK1/beclin-1/Atg5,7,12, ratio of LCB3-II/LC3B-I, p-AKT/m-TOR) were significantly higher in lung epithelial cells + 6h hypoxia as compared with the control, and those were significantly reversed by iPS-MSC treatment (all P < 0.001). Flow cytometric analysis revealed that percentages of the inflammatory cells in bronchioalveolar lavage fluid and circulation, and immune cells in circulation/spleen as well as circulatory early and late apoptotic cells were highest in group 2, lowest in group 1, and significantly higher in group 3 than in group 4 (all P < 0.0001). Microscopy showed the lung injury score and numbers of inflammatory cells and Western blot analysis showed the signaling pathways of inflammation, mitochondrial damage/cell apoptosis, autophagy, and oxidative stress exhibited an identical pattern of flow cytometric results among the four groups (all P < 0.0001). Both xenogeneic and allogenic MSCs protected the lung against IRI via suppressing the inflammatory, oxidative stress, and autophagic signaling.

Preactivated and disaggregated shape-changed platelets protect kidney against from ischemia-reperfusion injury in rat through attenuating inflammation reaction.

This study tested the hypothesis that preactivated and disaggregated shape-changed platelet (PreD-SCP) therapy significantly protected rat kidney from ischemia-reperfusion (IR) injury. Adult-male Sprague-Dawley rats (n = 24) were equally categorized into Groups 1 (sham-operated control [SC]), 2 (SC + PreD-SCP), 3 (IR only), and 4 (IR + PreD-SCP). By 72 hr after IR procedure, the circulatory levels of creatinine, blood urine nitrogen and inflammatory biomarkers (interleukin [IL]-6/tumor necrosis factor [TNF]-α), and ratio of urine protein to urine creatinine were significantly higher in Group 3 than in other groups and significantly higher in Group 4 than in Groups 1 and 2, but they showed no different between Groups 1 and 2 (all p < .001). The microscopic findings showed that the expressions of kidney injury score, cellular inflammation (MMP-9/CD14//F4/80), and fibrotic area were identical to the circulatory inflammation, whereas the integrity of podocyte components (ZO-1/synaptopodin/podocin) exhibited an opposite to circulatory inflammation among the four groups (all p < .0001). The protein expressions of inflammatory (TNF-α/IL-1ß/NF-κB/iNOS/TRAF6/MyD88/TLR-4), apoptotic/cell death (mitochondrial Bax/cleaved caspase-3/p-53), oxidized protein, mitogen-activated protein kinase family (p-38/p-JNK/p-c-JUN), and mitochondrial-damaged biomarkers displayed a similar pattern, whereas the antiapoptotic (Bcl-2/Bcl-XL) and integrity of mitochondrial biomarkers followed an opposite trend to circulatory inflammation among the four groups (all p < .001). PreD-SCP therapy effectively protected the kidney against IR injury.

Effect of vagus nerve stimulation on tissue damage and function loss in a mouse myocardial ischemia-reperfusion model.

In cardiac ischemia, acute inflammatory responses further increase the detrimental effect on myocardial tissue. Since vagus nerve stimulation (VS) attenuates inflammatory responsiveness this study examines the effect of VS on myocardial damage development in a cardiac ischemia-reperfusion (IR) mouse model. 54 male C57Bl/6j mice were subjected to an IR procedure with or without prior VS. The effects on inflammatory responsiveness, infarct size, cardiac function, neutrophils, lymphocytes and vascular endothelial growth factor (VEGF) in the infarcted myocardium were measured at 48 h after intervention. Group results were compared with unpaired Mann-Whitney or Kruskall-Wallis test. A significant decrease in inflammatory responsiveness was not verified by decreased TNFα levels in blood from VS and IR treated mice. The percentage infarct size over area at risk was smaller in the group with VS + IR compared with IR (22.4 ± 10.2% vs 37.6 ± 9.0%, p = 0.003). The degree of the reduction in cardiac function was not different between the IR groups with or without VS and no group differences were found in amounts of neutrophils, CD3+ lymphocytes and VEGF in the reperfused mouse heart. The present study does not provide clear evidence of a reducing role for VS on cardiac function loss. This could mean that VS has a less inhibiting effect on myocardial inflammation than may be expected from the literature.

Manual Therapy Reduces Pain Behavior and Oxidative Stress in a Murine Model of Complex Regional Pain Syndrome Type I.

Complex regional pain syndrome type I (CRPS-I) is a chronic painful condition. We investigated whether manual therapy (MT), in a chronic post-ischemia pain (CPIP) model, is capable of reducing pain behavior and oxidative stress. Male Swiss mice were subjected to ischemia-reperfusion (IR) to mimic CRPS-I. Animals received ankle joint mobilization 48h after the IR procedure, and response to mechanical stimuli was evaluated. For biochemical analyses, mitochondrial function as well as oxidative stress thiobarbituric acid reactive substances (TBARS), protein carbonyls, antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) levels were determined. IR induced mechanical hyperalgesia which was subsequently reduced by acute MT treatment. The concentrations of oxidative stress parameters were increased following IR with MT treatment preventing these increases in malondialdehyde (MDA) and carbonyls protein. IR diminished the levels of SOD and CAT activity and MT treatment prevented this decrease in CAT but not in SOD activity. IR also diminished mitochondrial complex activity, and MT treatment was ineffective in preventing this decrease. In conclusion, repeated sessions of MT resulted in antihyperalgesic effects mediated, at least partially, through the prevention of an increase of MDA and protein carbonyls levels and an improvement in the antioxidant defense system.

Castration induces antiapoptotic effects during myocardial regional ischemia reperfusion

Restoration of blood flow to ischemic myocardium results in the ischemia reperfusion (I/R) injury. This study was undertaken to investigate the potential role of endogenous testosterone in the regional ischemia reperfusion and apoptosis of the male rat hearts. Rats underwent surgical ligation of LAD and subjected to ischemia for 25 min and reperfusion for 40 min, and 2nd underwent surgical castration, left 3wks for recovery, then underwent surgical LAD ligation. Blood samples were collected from the heart for measurement of plasma level of cardiac troponin I (cTn-I). The hearts were harvested, and divided into 3 sections, the 1st for the measurement of cardiac apoptosis level, the 2nd homogenized for measurement of tissue (TNF-α, IL1-β, ICAM-1) and the 3rdwas fixed in 10% formalin for histological examination. Compared with the sham group, levels of tissue TNF-α &amp; IL-1β, ICAM-1 and apoptosis; plasma cTn-I were increased (P&lt;0.05) in the control group, all control group rats showed significant myocardial injury (P&lt;0.05) compared with the sham group. Castration significantly counteracts the increase in myocardial levels of TNF-α, IL-1, ICAM-1, plasma cTn-I and apoptosis (P&lt;0.05). Histological analysis revealed that castration markedly reduced (P&lt;0.05) the severity of the heart injury in the rats underwent the regional ischemia-reperfusion procedure. This study reveals that surgical castration may ameliorate regional I/R injury and apoptosis in the ischemic heart in rats.

PPAR gamma agonist, pioglitazone, rescues liver damage induced by renal ischemia/reperfusion injury

Remote organ damage is the major cause of death in patients with acute kidney injury (AKI) due to renal ischemia reperfusion (IR). Liver is one of the vital organs which are profoundly affected by AKI. The present study aims to investigate the role of peroxisome proliferator activator receptor gamma (PPARγ) in liver damage induced by IR injury in rats. Renal IR was induced by right nephrectomy, occlusion of left renal pedicle for 45 min to induce ischemia, and then reperfusion for 6 or 24 h. The PPARγ agonist, pioglitazone, was given orally for 7 days before renal IR procedure. Animals receiving pioglitazone showed improvement in renal and hepatic functions when compared to IR groups. Renal IR increased renal, hepatic and serum levels of tumor necrosis factor-α (TNF-α) and induced apoptotic cell death in liver. These effects were diminished with pioglitazone. In addition, pioglitazone reduced renal IR-induced oxidative stress in liver. Pioglitazone reduced malondialdehyde (MDA) content and NADPH oxidase mRNA expression and induced further increase in nuclear factor erythroid 2-related factor 2 (Nrf2) expression when compared to IR groups. Furthermore, pioglitazone increased the expression of PPARγ target genes such as renal and hepatic PPARγ1 (Pparg1), hepatic hemoxygenase-1 (Hmox1), and hepatic thioredoxin (TRx). Histological profiles for kidney and liver were also ameliorated with pioglitazone. Hence, PPARγ is a potential target to protect liver in patients with renal IR injury.