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Objective: Improvement of cell survival is essential for achieving better clinical outcomes in stem cell therapy. We investigated the effects of hyperoxic pre-treatment (HP) on the viability of human adipose stromal stem cells (ASCs). Materials and Methods: MTT and Western blot tests were used to assess cell viability and the expression of apoptosis-related proteins, respectively. For the in-vivo trial, the rats were subjected to renal ischaemia-reperfusion (IR). Results: The results showed that HP could significantly increase the viability of ASCs and decrease apoptotic markers (Bax/BCL-2 ratio and Caspase-3) compared with control cells. There were some additional effects with regard to the improvement of renal structure and function in the animal model. However, the difference between the treated and non-treated transplanted ASCs failed to reach significance. Conclusion: These results suggested that HP could increase the survival of ASCs against oxidative stress-induced damages in the in-vitro condition, but this strategy was not highly effective in renal IR. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is common following liver transplantation and is associated with liver ischeamia reperfusion (IR) injury. The purpose of this study was to use a mouse model of liver IR injury and AKI to study the role of Neutrophil Gelatinase Associated Lipocalin (NGAL), a biomarker of AKI, in liver IR injury and AKI. We demonstrate an adapted, reproducible model of liver IR injury and AKI in which remote ischemic preconditioning (RIPC) by repeated episodes of hindleg ischemia prior to liver IR reduced the severity of the IR injury. In this model, serum NGAL at 2 h post reperfusion correlated with AKI development early following IR injury. This early rise in serum NGAL was associated with hepatic but not renal upregulation of NGAL mRNA, suggesting NGAL production in the liver but not the kidney in the early phase post liver IR injury. [ABSTRACT FROM AUTHOR]

Deubiquitinases are a group of proteins that identify and digest monoubiquitin chains or polyubiquitin chains attached to substrate proteins, preventing the substrate protein from being degraded by the ubiquitin-proteasome system. Deubiquitinases regulate cellular autophagy, metabolism and oxidative stress by acting on different substrate proteins. Recent studies have revealed that deubiquitinases act as a critical regulator in various cardiac diseases, and control the onset and progression of cardiac disease through a board range of mechanism. This review summarizes the function of different deubiquitinases in cardiac disease, including cardiac hypertrophy, myocardial infarction and diabetes mellitus-related cardiac disease. Besides, this review briefly recapitulates the role of deubiquitinases modulators in cardiac disease, providing the potential therapeutic targets in the future. [ABSTRACT FROM AUTHOR]

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Copyright of Turkish Journal of Trauma & Emergency Surgery / Ulusal Travma ve Acil Cerrahi Dergisi is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Brain ischaemia is one of the leading causes of mortality and disability worldwide, and the damage caused by ischaemia not only induces primary damage but also that induced by ischaemia-reperfusion (I/R) injury. Multiple processes including inflammation and oxidative stress response play important roles in the development of brain ischaemia injury. Sevoflurane is a well-known volatile anaesthetic, and a recent study discovered the role of sevoflurane in suppression of the inflammation response process via inhibition of inflammatory infiltrates and production, maintaining the balance of cytokine responses, although the possible mechanism was not fully clear. NLRC3 is a member of the nucleotide-binding domain and leucine-rich repeat containing (NLR) family, and it has been regarded as a regulator of the inflammation process via the regulation of inflammasome formation, which is an initiator of inflammatory events. In the present study, we found that overexpression of NLRC3 reduced the apoptosis in a cellular model of ischaemia reperfusion, and the expression of pro-inflammatory cytokines was also decreased. Further study found that these effects might be mediated by the TRAF6/TLR4/NF-kB signalling pathway. Thus, we speculate that overexpression might enhance the effect of sevoflurane in inhibiting the inflammatory response process in an ischaemia reperfusion model, which might be a new therapeutic strategy.

Stroke is partial or complete brain dysfunction combined with acute cerebral circulatory disorders, and it affects millions of individuals around the world each year. A total of 70-80% of patients experience ischaemic stroke caused by disturbances in cerebral circulation, leading to cerebral ischaemia, neuronal apoptosis, and necrosis. Tanshinone IIA is a natural compound extracted from Salvia miltiorrhiza and has been proven to assist in recovery from cerebral ischaemia reperfusion injury. GLUT1 is ubiquitously expressed in all types of tissues in the human body and has important physiological functions due to its glucose uptake ability. This experiment was performed to detect the effect of GLUT1 in promoting the therapeutic effect of tanshinone IIA. Here, we found that tanshinone IIA treatment increased the viability of neurons and promoted the recovery of brain function, and that the concentration of glucose in serum and cultured medium was also increased. We noticed that these effects might be mediated by an increased glucose uptake ability. In addition, we further found that the PI3K/mTOR/HER3 signalling pathway played an important role in regulating these effects. Thus, we thought that overexpression of GLUT1 might be an important target in the treatment of cerebral ischaemia-reperfusion.

Hepatic ischaemia reperfusion injury (HIRI) is a major factor leading to liver dysfunction after liver resection and liver transplantation. Adipose‐derived mesenchymal stem cells (ADSCs) have potential therapeutic effects on HIRI. Exosomes derived from ADSCs (ADSCs‐exo) have been widely studied as an alternative of ADSCs therapy. Thus, the aim of this study was to evaluate the potential protective effect and related mechanism of ADSCs‐exo on HIRI subsequent to hepatectomy. Rats were randomly divided into four groups: Sham, I30R+PH, ADSCs and ADSCs‐exo group. After 24 h of reperfusion, liver and serum of the rats were immediately collected. ADSCs‐exo improved liver function, inhibited oxidative stress and reduced apoptosis of hepatocytes in HIRI subsequent to hepatectomy in rats. ADSCs‐exo significantly promoted the recovery of mitochondrial function, markedly increased the content of ATP in the liver tissue, and improved the ultrastructure of mitochondria in hepatocytes. Moreover, ADSCs‐exo significantly increased the expression of OPA‐1, MFN‐1 and MFN‐2 proteins related to mitochondrial fusion, while DRP‐1 and Fis‐1 mRNA and protein expression associated with mitochondrial fission were significantly decreased after the treatment with ADSCs‐exo. In addition, ADSCs‐exo significantly increased the expression of PGC‐1α, NRF‐1 and TFAM genes and proteins related to mitochondrial biogenesis. ADSCs‐exo improves liver function induced by HIRI subsequent to hepatectomy in rats and maintains mitochondrial homeostasis by inhibiting mitochondrial fission, promoting mitochondrial fusion and promoting mitochondrial biogenesis. Therefore, ADSCs‐exo may be considered as a potential promising alternative to ADSCs in the treatment of HIRI subsequent to hepatectomy. [ABSTRACT FROM AUTHOR]

Abstract Background Ischaemia reperfusion (IR) induces multiple pathophysiological changes. In addition to its classical role in regulating tumourigenesis, the feedback loop formed by p53 and its driven target p53-upregulated modulator of apoptosis (PUMA) was recently demonstrated to be the common node tightly controlling various cellular responses during myocardial IR. However, the roles of the p53-PUMA feedback loop in the spinal cord remain unclear. This study aimed to elucidate the roles of p53-PUMA feedback interactions in the spinal cord after IR, specifically investigating their regulation of caspase 3-mediated apoptosis and nuclear factor (NF)-κB-mediated cytokine release. Methods SD rats subjected to 12 min of aortic arch occlusion served as IR models. Neurological assessment as well as p53 and PUMA mRNA and protein expression analyses were performed at 12-h intervals during a 48-h reperfusion period. The cellular distributions of p53 and PUMA were determined via double immunofluorescence staining. The effects of the p53-PUMA feedback loop on modulating hind-limb function; the number of TUNEL-positive cells; and protein levels of caspase 3, NF-κB and cytokines interleukin (IL)-1β and tumour necrosis factor (TNF)-α, were evaluated by intrathecal treatment with PUMA-specific or scramble siRNA and pifithrin (PFT)-α. Blood-spinal cord barrier (BSCB) breakdown was examined by Evans blue (EB) extravasation and water content analyses. Results IR induced significant behavioural deficits as demonstrated by deceased Tarlov scores, which displayed trends opposite those of PUMA and p53 protein and mRNA expression. Upregulated PUMA and p53 fluorescent labels were widely distributed in neurons, astrocytes and microglia. Injecting si-PUMA and PFT-α exerted significant anti-apoptosis effects as shown by the reduced number of TUNEL-positive cells, nuclear abnormalities and cleaved caspase 3 levels at 48 h post-IR. Additionally, p53 colocalized with NF-κB within the cell. Similarly, injecting si-PUMA and PFT-α exerted anti-inflammatory effects as shown by the decreased NF-κB translocation and release of IL-1β and TNF-α. Additionally, injecting si-PUMA and PFT-α preserved the BSCB integrity as determined by decreased EB extravasation and spinal water content. However, injecting si-Con did not induce any of the abovementioned effects. Conclusions Inhibition of aberrant p53-PUMA feedback loop activation by intrathecal treatment with si-PUMA and PFT-α prevented IR-induced neuroapoptosis, inflammatory responses and BSCB breakdown by inactivating caspase 3-mediated apoptosis and NF-κB-mediated cytokine release.

Background: Endoplasmic reticulum (ER) perturbations are novel subcellular effectors involved in the ischaemia‐reperfusion injury. As an ER stress‐inducible protein, mesencephalic astrocyte‐derived neurotrophic factor (MANF) has been proven to be increased during ischaemic brain injury. However, the role of MANF in liver ischaemia reperfusion (I/R) injury has not yet been studied. Methods: To investigate the role of MANF in the process of liver ischaemia‐reperfusion, Hepatocyte‐specific MANF knockout (MANFhep−/−) mice and their wild‐type (WT) littermates were used in our research. Mice partial (70%) warm hepatic I/R model was established by vascular occlusion. We detected the serum levels of MANF in both liver transplant patients and WT mice before and after liver I/R injury. Recombinant human MANF (rhMANF) was injected into the tail vein before 1 hour occlusion. AST, ALT and Suzuki score were used to evaluate the extent of I/R injury. OGD/R test was performed on primary hepatocytes to simulate IRI in vitro. RNA sequence and RT‐PCR were used to detect the cellular signal pathway activation while MANF knockout. Results: We found that MANF expression and secretion are dramatically up‐regulated during hepatic I/R. Hepatocyte‐specific MANF knockout aggravates the I/R injury through the over‐activated ER stress. The systemic administration of rhMANF before ischaemia has the potential to ameliorate I/R‐triggered UPR and liver injury. Further study showed that MANF deficiency activated ATF4/CHOP and JNK/c‐JUN/CHOP pathways, and rhMANF inhibited the activation of the two proapoptotic pathways caused by MANF deletion. Conclusion: Collectively, our study unravels a previously unknown relationship among MANF, UPR and hepatic I/R injury. [ABSTRACT FROM AUTHOR]

Myocardial ischemia/reperfusion injury (MIRI) is a major cause of acute cardiac injury that is associated with high morbidity and mortality, and for which specific treatments are lacking. In this study, we investigated the underlying molecular mechanism of miR-144-3p in the pathological process of MIRI. A mouse I/R injury model and H9c2 cardiomyocyte hypoxia/reoxygenation (H/R) model were used to simulate the ischemia/reperfusion process in vivo and in vitro, respectively, and the relative expression and regulatory effect of miR-144-3p were determined. The target of miR-144-3p was also verified by a luciferase reporter assay. We found that miR-144-3p was significantly downregulated in mouse myocardium subjected to I/R and cardiomyocytes subjected to H/R. Upregulation of miR-144-3p significantly attenuated MIRI in vivo and in vitro. A Ca2+-activated chloride channel—TMEM16A (ANO1)—was identified as a target gene of miR-144-3p through bioinformatic analysis. The interaction between miR-144-3p and the 3ʹ-untranslated region of ANO1 was confirmed with dual-luciferase reporter assay, RNA immunoprecipitation assay, real-time quantitative polymerase chain reaction, and western blot analysis. Moreover, by targeting ANO1, miR-144-3p inhibited the activation of NLRP3 inflammasome inflammatory signals in myocardial cells. Collectively, the present study provides a novel insight into the role of miR-144-3p in the inhibition of MIRI, suggesting that the miR-144-3p/ANO1 axis may be a putative therapeutic target in myocardial ischemia. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) deficiency is known to play a role in renal ischaemia/reperfusion injury; therefore, kidney-targeting NO donor is expected to prevent renal ischaemia/reperfusion injury. We therefore developed an S-nitrosylated L-serine-modified polyamidoamine dendrimer (SNO-Ser-PAMAM), in which multiple S-nitrosothiols (NO donors) were covalently bound to L-serine-modified dendrimer, as a kidney-targeting NO donor. In the pharmacokinetic study, approximately 76% of 111In-SNO-Ser-PAMAM accumulated in the kidney after intravenous injection in mice. Furthermore, single photon emission computed tomography/computed tomography (SPECT/CT) imaging study showed that 111In-SNO-Ser-PAMAM specifically accumulated in the renal cortex after intravenous injection. SNO-Ser-PAMAM gradually released NO over a day in plasma, indicating that SNO-Ser-PAMAM would show sustained release of NO in vivo. In a mouse model of renal ischaemia/reperfusion injury, increased plasma creatinine, a kidney damage marker, and histological changes were effectively inhibited by intravenous administration of SNO-Ser-PAMAM. These results indicate that SNO-Ser-PAMAM is a promising kidney-targeting NO donor for the efficient prevention of renal ischaemia/reperfusion injury. [ABSTRACT FROM AUTHOR]

Stroke is partial or complete brain dysfunction combined with acute cerebral circulatory disorders, and it affects millions of individuals around the world each year. A total of 70-80% of patients experience ischaemic stroke caused by disturbances in cerebral circulation, leading to cerebral ischaemia, neuronal apoptosis, and necrosis. Tanshinone IIA is a natural compound extracted from Salvia miltiorrhiza and has been proven to assist in recovery from cerebral ischaemia reperfusion injury. GLUT1 is ubiquitously expressed in all types of tissues in the human body and has important physiological functions due to its glucose uptake ability. This experiment was performed to detect the effect of GLUT1 in promoting the therapeutic effect of tanshinone IIA. Here, we found that tanshinone IIA treatment increased the viability of neurons and promoted the recovery of brain function, and that the concentration of glucose in serum and cultured medium was also increased. We noticed that these effects might be mediated by an increased glucose uptake ability. In addition, we further found that the PI3K/mTOR/HER3 signalling pathway played an important role in regulating these effects. Thus, we thought that overexpression of GLUT1 might be an important target in the treatment of cerebral ischaemia-reperfusion. [ABSTRACT FROM AUTHOR]

Background: Myocardial ischaemia/reperfusion (MI/R) may induce renal damage. Our aim was to investigate the effects of dexmedetomidine (DEX) administration at two different timings either before or after ischaemia on renal damage induced by MI/R. Methods: MI/R injury was induced in a rat model. we ligated the left anterior descending coronary artery for 30 min (ischaemic period), then reperfusion occurred for 2 h (reperfusion period). A single dose of DEX (100 µg/kg) was given intraperitoneally, either 30 min before myocardial ischaemia or 5 min after reperfusion. With the end of reperfusion period, rats were sacrificed, then we collected the blood and removed both kidneys quickly for biochemical and histopathological analysis. Results: MI/R caused an elevation in serum urea and creatinine, significant elevation in malondialdehyde (MDA) release and decrease in superoxide dismutase (SOD) activity in the rat kidney. There were also higher levels of serum tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β). Treatment with dexmedetomidine, 30 min before induction of myocardial ischaemia, succeeded to improve all the tested parameters. The valuable changes in these biochemical parameters were linked with similar enhancement in the histopathological appearance of the kidney. Meanwhile, DEX given 5 min after reperfusion improved serum urea and creatinine only. Conclusion: These findings imply that MI/R plays a fundamental role in kidney damage through increased production of oxygen radicals or deficiency in antioxidants, and DEX given before ischaemia exerts reno-protective effects probably by its radical scavenging antioxidant activity and anti-inflammatory mechanism.

Apoptosis is an inborn process that has been preserved during evolution; it allows the cells to systematically inactivate, destroy and dispose of their own components thus leading to their death. This program can be activated by both intra and extracellular mechanisms. The intracellular components involve a genetically defined development program while the extracellular aspects regard endogenous proteins, cytokines and hormones as well as xenobiotics, radiations, oxidative stress and hypoxia. The ability of a cell to enter apoptosis as a response to a „death" signal depends on its proliferative status, the position in the cell cycle and also on the controlled expression of those genes that have the capacity of promoting and inhibiting cell death. The fine regulation of these parameters needs to be maintained in order to ensure the physiological environment required for the induction of apoptosis. In this review, we first describe evidence for the role of apoptotic pathways in ischemic acute renal failure, and then consider the potentialmechanisms thatmay participate in thismodel of acute renal tubular injury. Potential therapeutic interventions to prevent tubular apoptosis in renal disease include angiotensin system inhibition, whereby the angiotensin II AT2 receptor blockade seems more promising in apoptosis inhibition than the inhibition of other receptor subtypes. A better understanding of the mechanisms of apoptosis could lead to safer and more specific therapeutic interventions for acute kidney injury. [ABSTRACT FROM AUTHOR]

Liver disease causing end organ failure is a growing cause of mortality. In most cases, the only therapy is liver transplantation. However, liver transplantation is a complex undertaking and its success is dependent on a number of factors. In particular, liver transplantation is subject to the risks of ischaemia‐reperfusion injury (IRI). Liver IRI has significant effects on the function of a liver after transplantation. The cellular and molecular mechanisms governing IRI in liver transplantation are numerous. They involve multiple cells types such as liver sinusoidal endothelial cells, hepatocytes, Kupffer cells, neutrophils and platelets acting via an interconnected network of molecular pathways such as activation of toll‐like receptor signalling, alterations in micro‐RNA expression, production of ROS, regulation of autophagy and activation of hypoxia‐inducible factors. Interestingly, the cellular and molecular events in liver IRI can be correlated with clinical risk factors for IRI in liver transplantation such as donor organ steatosis, ischaemic times, donor age, and donor and recipient coagulopathy. Thus, understanding the relationship of the clinical risk factors for liver IRI to the cellular and molecular mechanisms that govern it is critical to higher levels of success after liver transplantation. This in turn will help in the discovery of therapeutics for IRI in liver transplantation – a process that will lead to improved outcomes for patients suffering from end‐stage liver disease. [ABSTRACT FROM AUTHOR]

Objective: Diabetic complications and lipid peroxidation are known to have a close association. Lipid peroxidation commonly occurs at sites exposed to ischaemia, but distant organs and tissues also get damaged during ischaemia/reperfusion (I/R). Some of these targets are vital organs, such as the lung, liver, and kidney; the lung is the most frequently affected. The aim of our study was to investigate the effects of dexmedetomidine on I/R damage in lung tissue and on the oxidant/anti-oxidant system in diabetic rats. Material and methods: Diabetes was induced with streptozotocin (55 mg/kg) in 18 Wistar Albino rats, which were then randomly divided into three groups (diabetes control (DC), diabetes plus ischaemia-reperfusion (DIR), and diabetes plus dexmedetomidine-ischaemia/reperfusion (DIRD)) after the effects of diabetes were clearly evident. The rats underwent a left thoracotomy and then ischaemia was produced in the myocardium muscle by a left anterior descending artery ligation for 30 min in the DIR and DIRD groups. I/R was performed for 120 min. The DIRD group received a single intraperitoneal dose of dexmedetomidine (100 µg/kg); the DIR group received no dexmedetomidine. Group DC was evaluated as the diabetic control group and also included six rats (C group) in which diabetes was not induced. These mice underwent only left thoracotomy and were closed without undergoing myocardial ischaemia. Histopathological changes, activities of catalase (CAT) and glutathione-S-transferase anti-oxidant enzymes, and malondialdehyde (MDA) levels were evaluated in the lung tissues of all rats. Results: Neutrophil infiltration/aggregation was higher in the DIR group than in the C, DC, and DIRD groups (p=0.001, p=0.013, and p=0.042, respectively). The lung injury score was significantly higher in the DIR group than in the C and DC groups (p

Aims Monocyte-mediated inflammation is a major mechanism underlying myocardial ischaemia–reperfusion (IR) injury and the healing process after acute myocardial infarction (AMI). However, no definitive anti-inflammatory therapies have been developed for clinical use. Pioglitazone, a peroxisome proliferator-activated receptor-gamma (PPARγ) agonist, has unique anti-inflammatory effects on monocytes/macrophages. Here, we tested the hypothesis that nanoparticle (NP)-mediated targeting of pioglitazone to monocytes/macrophages ameliorates IR injury and cardiac remodelling in preclinical animal models. Methods and results We formulated poly (lactic acid/glycolic acid) NPs containing pioglitazone (pioglitazone-NPs). In a mouse IR model, these NPs were delivered predominantly to circulating monocytes and macrophages in the IR heart. Intravenous treatment with pioglitazone-NPs at the time of reperfusion attenuated IR injury. This effect was abrogated by pre-treatment with the PPARγ antagonist GW9662. In contrast, treatment with a pioglitazone solution had no therapeutic effects on IR injury. Pioglitazone-NPs inhibited Ly6Chigh inflammatory monocyte recruitment as well as inflammatory gene expression in the IR hearts. In a mouse myocardial infarction model, intravenous treatment with pioglitazone-NPs for three consecutive days, starting 6 h after left anterior descending artery ligation, attenuated cardiac remodelling by reducing macrophage recruitment and polarizing macrophages towards the pro-healing M2 phenotype. Furthermore, pioglitazone-NPs significantly decreased mortality after MI. Finally, in a conscious porcine model of myocardial IR, pioglitazone-NPs induced cardioprotection from reperfused infarction, thus providing pre-clinical proof of concept. Conclusion NP-mediated targeting of pioglitazone to inflammatory monocytes protected the heart from IR injury and cardiac remodelling by antagonizing monocyte/macrophage-mediated acute inflammation and promoting cardiac healing after AMI. [ABSTRACT FROM AUTHOR]

Abstract Penehyclidine hydrochloride (PHC) is a new anticholinergic agent that provides protective effects in experimental models of heart and brain ischaemia as well as reperfusion (I/R) injury. In this study, we tested the hypothesis that PHC can alleviate lung ischaemia-reperfusion injury and improve pulmonary and systemic function in rats. PHC was administered intravenously at various doses (d= 0.1, 0.3, 1, 3 mg/kg) to I/R rats. We used six indicators, including lung function, histologic examination, pulmonary oedema, oxidative stress, inflammatory responses, and apoptosis staining to quantify the pulmonary and systemic protective effects of PHC. Haematoxylin and eosin staining was used for pulmonary histologic examination. The expression of Toll-like receptor (TLR) 4, phospho-inhibitor of NF-κB (p-IκB) and nuclear factor-kappa B (NF-κB) was analysed using western blotting. ELISA was conducted to detect inflammatory mediators. Oxidative stress markers as well as myeloperoxidase (MPO) were determined using an assay kit. PHC preconditioning (with concentrations ranging from 0.3 mg/kg to 3 mg/kg 30 min before the onset of I/R) significantly reduced lung histopathological changes, down regulated TLR4, p-IκB and NF-κB expression, and decreased inflammatory mediators as well as the total number of leukocytes and neutrophils in bronchoalveolar lavage (BAL) fluid and plasma. The lung tissue contents of reactive oxygen species (ROS), malondialdehyde (MDA), and MPO as well as pulmonary oedema formation decreased, while SOD (superoxide dismutase) activity was significantly upregulated. PHC preconditioning (with concentrations ranging from 1 mg/kg to 3 mg/kg) significantly improved the lung function and attenuated the apoptotic rate. The probable mechanism for this finding is the inhibition of proinflammatory mediators via the suppression of reactive oxygen species production and the TLR4/NF-κB signalling pathway. [ABSTRACT FROM AUTHOR]

Objective/background The aim of this study was to investigate whether antioxidant therapy might decrease oxidative stress related deleterious effects in the setting of critical limb ischaemia (CLI). Methods Twenty Swiss mice were submitted to sequential right femoral and iliac ligatures; the left limb served as control. The mice were assigned to two groups: in the first group (no-treatment group, n = 10) no treatment was administered; in the second group (N -acetyl cysteine [NAC] group, n = 10) NAC was administered by dissolution in drinking water for 4 weeks, starting on day 7, when CLI was effective. Clinical and functional scores were assessed by two blinded investigators. Mice were killed on day 40 and mitochondrial respiratory chain complex activities, calcium retention capacity, oxidative stress, and histological analysis were analysed. Results Ischaemic muscles in the no-treatment group showed significantly impaired mitochondrial respiration and calcium retention capacity, with increased production of reactive oxygen species; but no statistical difference was noticed when comparing ischaemic muscles in the NAC group (n = 10) to contralateral muscles (n = 10) and to control muscles in the no-treatment group (n = 10). Ischaemic muscles in the no-treatment group exhibited myopathic features such as wider range in fibre size, rounded shape, centrally located nuclei, and smaller cross sectional areas, but none of these features were observed in contralateral muscles or in NAC-group muscles (ischaemic or controls). Conclusion Targeting inhibition of oxidative stress may be a potential therapeutic strategy for muscle protection in CLI and might be considered as potential adjunctive therapy to revascularisation procedures. [ABSTRACT FROM AUTHOR]

Aims To study the protective effects of late remote ischaemic preconditioning (RIPC) against myocardial ischaemia/reperfusion (I/R) injury and determine whether Stat5 is involved in this protection by using cardiomyocyte-specific Stat5 knockout mice (Stat5-cKO). Methods and results Mice were exposed to lower limb RIPC or sham ischaemia. After 24 h, the left anterior descending artery (LAD) was ligated for 30 min, then reperfused for 180 min. The myocardial infarct size (IS), apoptotic rate of cardiomyocytes, and serum myocardial enzymes were measured to evaluate for cardioprotective effects. Heart tissues were harvested to determine the cardiomyocytes' anti-apoptotic and survival signaling. When compared with the Stat5fl/fl mice without RIPC, Stat5fl/fl mice with RIPC (Stat5fl/fl+RIPC + I/R) displayed a decreased myocardial IS/LV (16 ± 1.5 vs. 30.1 ± 3.1%, P < 0.01; IS/ area at risk (AAR), 42.2 ± 3.5 vs. 69.2 ± 4.9%, P < 0.01), a reduced cardiomyocyte apoptotic rate (2.1 ± 0.37 vs. 5.5 ± 0.53%, P < 0.01), and lower creatine kinase (CK), lactate dehydrogenase (LDH), and creatine kinase-MB (CK-MB) levels. To the contrary, the Stat5-cKO mice (Stat5fl/fl; Tnnt2Cre mice with Doxycycline treatment for 7 days) did not exhibit any effect of RIPC-induced cardioprotection. Activation of STAT5 protein was significantly higher in the Stat5fl/fl+RIPC + I/R group than in the Stat5fl/fl+I/R group, while there was no significant difference between the Stat5-cKO + RIPC + I/R and the Stat5-cKO + I/R group. Further analyses with heart tissues detected decreased protein expressions of cytochrome c (Cyt c) and cleaved Caspase-3 in the Stat5fl/fl+RIPC + I/R mice, along with increased anti-apoptotic molecules, including B-cell lymphoma-extra large (Bcl-xL) and B-cell lymphoma-2 (Bcl-2); such changes were not noted in the Stat5-cKO + RIPC + I/R mice. Additionally, RIPC increased cardiac hypoxia inducible factor-1 (HIF-1a) and interleukin-10 (IL10) protein levels and caused activation of AKT, phosphatidylinositol 3 kinase (PI3K), and vascular endothelial growth factor in the heart of the Stat5fl/fl mice. However, these changes were completely inhibited by the absence of Stat5. Conclusions These results suggest that RIPC-induced late cardioprotection against myocardial I/R injury is Stat5-dependent and is correlated with the activation of anti-apoptotic signaling and cardiomyocyte-survival signaling. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Crateva nurvala stem bark is commonly used in Ayruveda in treatment of many renal injuries, e.g., urinary lithiasis, diuretic and nephroprotective. However, its protective effect against renal ischaemia/reperfusion, the major cause of acute kidney injury, has never been studied. Moreover, no comprehensive chemical profiling of its extracts was recorded. Aim of the study Assessment of the protective effect of the plant extracts against renal ischaemia/reperfusion and elucidation of the possible mechanism of action. Then, to determine its bioactive constituents using modern UPLC-HRMS technique. Material and methods Unilateral ischaemia was induced by clamping the left renal artery for 1 h then reperfusion for 24 h. Rats were divided in 4 groups: i) sham-operated group, ii) ischaemia/reperfusion, I/R group, iii) I/R protected by previous administration of Crateva leaves extract, CLE group and iv) I/R protected by previous administration of Crateva bark extract, CBE group. At the end of reperfusion, blood samples were analyzed for renal function biomarkers. Kidneys were examined histopathologically and their homogenates were used in determining the intracellular levels of oxidative stress, inflammatory, and apoptosis markers. Results Leaves and bark extracts attenuated the deleterious effects of I/R apparent in reducing LDH, creatinine and blood urea nitrogen levels. The extracts reduced the oxidative stress by replenishing the glutathione levels and Nrf2 factor levels. Moreover, extracts decreased levels of pro-inflammatory TNF-α, NF-κβ and IL-6; which ultimately resulted in reducing the pro-apoptotic caspase-3. Bark and leave extracts have quite similar chemical profile where 42 compounds of various chemical classes were identified. Flavonoids are the major class of the bioactive phytochemicals Conclusion C. nurvala extracts had effectively ameliorated the deleterious effects of renal I/R by mainly counteracting oxidative stress and presumably inflammation. Consequently, it can be used as a complementary treatment with other agents. In this aspect, leaves stand as a sustainable alternative to bark. The presented chemical profiling can be used in future standardization and quality control of the drug. [ABSTRACT FROM AUTHOR]

Class 1 level A evidence now supports endovascular thrombectomy as best practice in the management of large vessel occlusion acute ischaemic stroke. However, significant questions pertaining to initial imaging, radiological assessment, patient selection and therapeutic limits remain unanswered. A specific cohort of patients who benefit from endovascular thrombectomy has been established, although current uncertainties regarding selection of those not meeting top-tier evidence criteria may potentially deny certain patients the benefit of intervention. This is of particular relevance in patients presenting in a delayed manner. Whilst superior outcomes are achieved with reduced time to endovascular reperfusion, denying patients intervention based on symptom duration alone may not be appropriate. Advanced understanding of ischaemic stroke pathophysiology supports an individualized approach to patient evaluation, given variance in the rate of ischaemic core progression and the extent of salvageable penumbra. Physiological imaging techniques may therefore be utilized to better inform patient selection for endovascular thrombectomy and evidence suggests that a transition from time-based to tissue-based therapeutic thresholds may be of greater value. Multiple ongoing randomized controlled trials aim to further define the benefit of endovascular thrombectomy and it is hoped that these results will advance, and possibly broaden, patient selection criteria to ensure that maximum benefit from the intervention may be achieved. [ABSTRACT FROM AUTHOR]

Background Myocardial ischaemia/reperfusion (MI/R) may induce renal damage. Our aim was to investigate the effects of dexmedetomidine (DEX) administration at two different timings either before or after ischaemia on renal damage induced by MI/R. Methods MI/R injury was induced in a rat model. we ligated the left anterior descending coronary artery for 30 min (ischaemic period), then reperfusion occurred for 2 h (reperfusion period). A single dose of DEX (100 µg/kg) was given intraperitoneally, either 30 min before myocardial ischaemia or 5 min after reperfusion. With the end of reperfusion period, rats were sacrificed, then we collected the blood and removed both kidneys quickly for biochemical and histopathological analysis. Results MI/R caused an elevation in serum urea and creatinine, significant elevation in malondialdehyde (MDA) release and decrease in superoxide dismutase (SOD) activity in the rat kidney. There were also higher levels of serum tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β). Treatment with dexmedetomidine, 30 min before induction of myocardial ischaemia, succeeded to improve all the tested parameters. The valuable changes in these biochemical parameters were linked with similar enhancement in the histopathological appearance of the kidney. Meanwhile, DEX given 5 min after reperfusion improved serum urea and creatinine only. Conclusion These findings imply that MI/R plays a fundamental role in kidney damage through increased production of oxygen radicals or deficiency in antioxidants, and DEX given before ischaemia exerts reno-protective effects probably by its radical scavenging antioxidant activity and anti-inflammatory mechanism. [ABSTRACT FROM AUTHOR]

Renal ischaemia-reperfusion (I/R) injury is the most common cause of acute kidney injury (AKI). Peritubular capillary (PTC) endothelium damages are an important pathogenesis during I/R AKI. Salvianolic acid A (SAA) possesses various pharmacological activities. The study investigated whether SAA ameliorated I/R AKI through protecting against PTC endothelium damages. Male Sprague-Dawley rats were divided into 6 groups: control, sham, I/R, and I/R plus SAA (2.5, 5, 10 mg/kg) groups. Rats were subjected to bilateral renal pedicle clamping for 60 min, and killed at 24 hr after reperfusion. Kidney injury, PTC endothelium damages and factors affecting PTC endothelium were evaluated. SAA significantly decreased blood urea nitrogen and serum creatinine levels, and reduced urine kidney injury molecule-1 concentration. Simultaneously, SAA alleviated histological damages, prevented PTC endothelium damages, preserved the density of PTC and improved renal hypoxia. Furthermore, SAA inhibited platelet activation, elevated Klotho protein expression and up-regulated vascular endothelial growth factor A expression. Overall, SAA has protective effects on AKI induced by I/R. Preventing PTC endothelium damages and preserving PTC integrity to improve the renal hypoxia may be the ways for SAA to ameliorate AKI. All these indicate that SAA is likely to be a promising agent for AKI. [ABSTRACT FROM AUTHOR]

Background and Objectives: Benefit from endovascular thrombectomy (EVT) for large-vessel occlusion (LVO) acute ischaemic stroke (AIS) is well demonstrated. Furthermore, emerging evidence supports efficacy in appropriately selected patients treated beyond current recommendations of 6 h. We evaluated clinical outcomes in patients undergoing late EVT at our institution.Methods: Retrospective review of prospectively collected clinical database on 355 patients who underwent EVT for LVO AIS. Data collected consisted of patient demographics, radiological findings and outcome details. Outcomes, including 90-day functional status, recanalization, symptomatic intracranial haemorrhage (sICH) and 90-day mortality, for patients undergoing EVT <6 h, >6 h, and >7.3 h, were compared.Results: A total of 355 patients underwent EVT for LVO AIS at our institution during the review period, with 74 (21%) patients treated ≥6 h from symptom onset. Successful recanalization was achieved in 285 (80%) patients, with 228 (81%) achieving a mTICI ≥2b in the <6 h group, and 57 (77%) in the >6 h group (P = 0.429). Ninety-day functional independence (mRS 0-2) was achieved in 162 (46%) patients, with 130 (46%) achieving a mRS of 0-2 in the <6 h group, and 32 (43%) in the >6 h group (P = 0.643). No significant differences were found in rates of sICH or 90-day mortality. No significant differences in functional independence, recanalization rates, sICH or mortality were identified in patients treated with EVT >7.3 h compared to <7.3 h.Conclusions: In appropriately selected patients, EVT >6 h was associated with comparable outcomes to those treated <6 h. These data support a physiological approach to patient selection. [ABSTRACT FROM AUTHOR]

The liver, the largest organ with multiple synthesis and secretion functions in mammals, consists of hepatocytes and Kupffer, stem, endothelial, stellate and other parenchymal cells. Because of early and extensive contact with the external environment, hepatic ischaemia reperfusion (IR) may result in mitochondrial dysfunction, autophagy and apoptosis of cells and tissues under various pathological conditions. Because the liver requires a high oxygen supply to maintain normal detoxification and synthesis functions, it is extremely susceptible to ischaemia and subsequent reperfusion with blood. Consequently, hepatic IR leads to acute or chronic liver failure and significantly increases the total rate of morbidity and mortality through multiple regulatory mechanisms. An increasing number of studies indicate that mitochondrial structure and function are impaired after hepatic IR, but that the health of liver tissues or liver grafts can be effectively rescued by attenuation of mitochondrial dysfunction. In this review, we mainly focus on the subsequent therapeutic interventions related to the conservation of mitochondrial function involved in mitigating hepatic IR injury and the potential mechanisms of protection. Because mitochondria are abundant in liver tissue, clarification of the regulatory mechanisms between mitochondrial dysfunction and hepatic IR should shed light on clinical therapies for alleviating hepatic IR-induced injury. [ABSTRACT FROM AUTHOR]

Aim The aim of this article is to test the hypothesis that remote ischaemic preconditioning (RIPC) increases circulating endogenous local and systemic plasma (nitrite) during RIPC and ischaemia-reperfusion (IR) as a potential protective mechanism against ischaemia-reperfusion injury (IRI). Methods Six healthy male volunteers (mean age 29.5 ± 7.6 years) were randomized in a crossover study to initially receive either RIPC (4 × 5 min cycles) to the left arm, or no RIPC (control), both followed by an ischaemia-reperfusion (IR) sequence (20 min cuff inflation to 200 mmHg, 20 min reperfusion) to the right arm. The volunteers returned at least 7 days later for the alternate intervention. The primary outcome was the effect of RIPC vs. control on local and systemic plasma (nitrite). Results RIPC did not significantly change plasma (nitrite) in either the left or the right arm during the RIPC sequence. However, compared to control, RIPC decreased plasma (nitrite) during the subsequent IR sequence by ~26% (from 118 ± 9 to 87 ± 5 nmol l−1) locally in the left arm ( P = 0.008) overall, with an independent effect of −58.70 nmol l−1 (95% confidence intervals −116.1 to −1.33) at 15 min reperfusion, and by ~24% (from 109 ± 9 to 83 ± 7 nmol l−1) systemically in the right arm ( P = 0.03). Conclusions RIPC had no effect on plasma (nitrite) during the RIPC sequence, but instead decreased plasma (nitrite) by ~25% during IR. This would likely counteract the protective mechanisms of RIPC, and contribute to RIPC's lack of efficacy, as observed in recent clinical trials. A combined approach of RIPC with nitrite administration may be required. [ABSTRACT FROM AUTHOR]

Resumo Objetivos O objetivo do presente estudo foi investigar os efeitos preventivos de propofol e cetamina em sedação com doses baixas durante a raquianestesia sobre lesão de isquemia‐reperfusão induzida por torniquete. Métodos 30 pacientes foram randomicamente alocados em dois grupos de 15 pacientes cada. No grupo propofol, a sedação foi feita com 0,2 mg.kg ‐1 de propofol seguida por infusão a uma taxa de 2 mg.kg ‐1 .h ‐1 . No grupo cetamina, uma infusão contínua de 0,5 mg.kg ‐1 .h ‐1 de cetamina foi usada até o final da cirurgia. Midazolam intravenoso não foi administrado em nenhum dos pacientes. A Escala de Sedação de Ramsay (ESR) foi usada para avaliar o nível de sedação. Amostras de sangue venoso foram colhidas antes da administração de propofol e infusão de cetamina (T1), aos 30 minutos (min) de isquemia do torniquete (T2) e 5 min após a desinsuflação do torniquete (T3), para medir os valores de malondialdeído (MDA). Resultados Não observamos diferenças entre os grupos em relação à hemodinâmica ( p > 0,05) e dados demográficos ( p > 0,05). Não houve diferença estatisticamente significativa entre os dois grupos nos períodos T1, T2 e T3 ( p > 0,05). Um aumento estatisticamente significativo foi observado nos valores de MDA, respectivamente, no Grupo P e Grupo C entre os períodos de reperfusão (1,95 ± 0,59, 2,31 ± 0,48) e pré‐isquemia (1,41 ± 0,38, 1,54 ± 0,45) e isquemia (1,76 ± 0,70, 1,71 ± 0,38) (μmoL −1 ) ( p < 0,05). Conclusões Propofol e cetamina em doses baixas apresentam potencial semelhante para reduzir o estresse oxidativo causado pela lesão de isquemia‐reperfusão induzida por torniquete em pacientes submetidos à artroscopia de joelho sob raquianestesia. Objectives The aim of the present study was to investigate the preventive effects of propofol and ketamine as small dose sedation during spinal anesthesia on tourniquet‐induced ischemia‐reperfusion injury. Methods 30 patients were randomly assigned into two groups of 15 patients. In the propofol group, sedation was performed with propofol 0.2 mg.kg ‐1 followed by infusion at a rate of 2 mg.kg ‐1 .h ‐1 . In the ketamine group, a continuous infusion of ketamine 0.5 mg.kg ‐1 .h ‐1 was used until the end of surgery. Intravenous administration of midazolam was not used in any patients. Ramsay sedation scale was used for assessing the sedation level. Venous blood samples were obtained before propofol and ketamine infusion (T1), at 30 minutes (min) of tourniquet ischemia (T2), and 5 min after tourniquet deflation (T3) for malondialdehyde (MDA) measurements. Results No differences were noted between the groups in hemodynamic ( p > 0.05) and demographic data ( p > 0.05). There was no statistically significant difference between the two groups in terms of T1, T2 and T3 periods ( p > 0.05). There was a statistically increase observed in MDA values respectively both in Group P and Group K between the reperfusion period (1.95 ± 0.59, 2.31 ± 0.48) and pre‐ischemia (1.41 ± 0.38, 1.54 ± 0.45), and ischemia (1.76 ± 0.70, 1.71 ± 0.38) (μmoL ‐1 ) periods ( p < 0.05). Conclusions Small‐dose propofol and ketamine has similar potential to reduce the oxidative stress caused by tourniquet‐induced ischemia‐reperfusion injury in patients undergoing arthroscopic knee surgery under spinal anesthesia. [ABSTRACT FROM AUTHOR]

Caveolae, lipid enriched invaginations of the plasma membrane, are epicentres of cellular signal transduction. The structural proteins of caveolae, caveolins, regulate effector pathways in anaesthetic-induced cardioprotection, including the RISK pathway. Helium (He) postconditioning (HePoc) is known to mimic anaesthetic conditioning and to prevent damage from myocardial infarction. We hypothesize that HePoc regulates caveolin-1 and caveolin-3 (Cav-1 and Cav-3) expression in the rat heart and activates the RISK pathway. Male Wistar rats (n=8, each group) were subjected to 25 min of cardiac ischaemia followed by reperfusion (I/R) for 5, 15 or 30 min (I/R 5/15/30). The HePoc groups underwent I/R with 70% helium ventilation during reperfusion (IR+He 5/15/30 min). Sham animals received surgical treatment without I/R. After each protocol blood and hearts were retrieved. Tissue was obtained from the area-at-risk (AAR) and non-area-at-risk (NAAR) and processed for western blot analyses and reverse-transcription-real-time-polymerase-chain-reaction (RT-qPCR). Protein analyses revealed increased amounts of Cav-1 and Cav-3 in the membrane of I/R+He15 (AAR: Cav-1, P<0.05; Cav-3, P<0.05; both vs. I/R15). In serum, Cav-3 was found to be elevated in I/R+He15 (P<0.05 vs. I/R15). RT-qPCR showed increased expression of Cav-1 in IR+He15 in AAR tissue (P<0.05 vs. I/R15). Phosphorylation of RISK pathway proteins pERK1/2 (AAR: P<0.05 vs. I/R15) and pAKT (AAR: P<0.05; NAAR P<0.05; both vs. I/R15) was elevated in the cytosolic fraction of I/R+He15. These results suggest that 15 min of HePoc regulates Cav-1 and Cav-3 and activates RISK pathway kinases ERK1/2 and AKT. These processes might be crucially involved in HePoc mediated cardioprotection. [ABSTRACT FROM AUTHOR]