Science.gov

Sample records for ischemic renal injury

  1. Ischemic preconditioning attenuates functional, metabolic, and morphologic injury from ischemic acute renal failure in the rat.

    PubMed

    Cochrane, J; Williams, B T; Banerjee, A; Harken, A H; Burke, T J; Cairns, C B; Shapiro, J I

    1999-03-01

    Ischemic preconditioning has been shown to ameliorate injury due to subsequent ischemia in several organs. However, relatively little is known about preconditioning and the kidney. To address this, rats were randomized to control (C, N = 14), 2 min of ischemic preconditioning (P2 N = 10), 3 periods of 2 min of ischemia separated by 5 min periods of reflow (P2,3 N = 7), or three 5 min periods of ischemia separated by 5 min of reflow (P5,3 N = 6) prior to 45 min of bilateral renal ischemia followed by 24 hours of reperfusion. We observed a lower serum creatinine after 24 hours of reflow in P2, P2, 3 but not P5, 3 rats compared with C. Histology was examined in the C and P2, 3 groups and demonstrated less severe injury in the P2, 3 group. To gain insight into the mechanism by which preconditioning ameliorated ischemic injury, we performed near IR spectroscopy and 31P NMR spectroscopy. Based on near IR spectroscopy, the P2, 3 group had closer coupling of cytochrome aa3 redox state with that of hemoglobin during reflow. In the 31P NMR studies, the changes in ATP and pHi were similar during ischemia, but the P2, 3 group recovered ATP and pHi faster than C. These data suggest that ischemic preconditioning may ameliorate ischemic renal injury as assessed by functional, metabolic and morphological methods. The mechanism(s) by which this occurs requires additional study. PMID:10088174

  2. Ameliorative Effect of Recombinant Human Erythropoietin and Ischemic Preconditioning on Renal Ischemia Reperfusion Injury in Rats

    PubMed Central

    Elshiekh, Mohammed; Kadkhodaee, Mehri; Seifi, Behjat; Ranjbaran, Mina; Ahghari, Parisa

    2015-01-01

    Background: Ischemia-reperfusion (IR) injury is one of the most common causes of renal dysfunction. There is increasing evidence about the role of the reactive oxygen species (ROS) in these injuries and endogenous antioxidants seem to have an important role in decreasing the renal tissue injury. Objectives: The aim of this study was to compare the effect of recombinant human erythropoietin (EPO) and ischemic preconditioning (IPC) on renal IR injury. Materials and Methods: Twenty four male Wistar rats were allocated into four experimental groups: sham-operated, IR, EPO + IR, and IPC + IR. Rats were underwent 50 minutes bilateral ischemia followed by 24 hours reperfusion. Erythropoietin (5000 IU/kg, i.p) was administered 30 minutes before onset of ischemia. Ischemic preconditioning was performed by three cycles of 3 minutes ischemia followed by 3 minutes reperfusion. Plasma concentrations of urea and creatinine were measured. Kidney samples were taken for reactive oxidative species (ROS) measurement including superoxide dismutase (SOD) activity, glutathione (GSH) contents, and malondialdehyde (MDA) levels. Results: Compared to the sham group, IR led to renal dysfunction as evidenced by significantly higher plasma urea and creatinine. Treatment with EPO or IPC decreased urea, creatinine, and renal MDA levels and increased SOD activity and GSH contents in the kidney. Conclusions: Pretreatment with EPO and application of IPC significantly ameliorated the renal injury induced by bilateral renal IR. However, both treatments attenuated renal dysfunction and oxidative stress in kidney tissues. There were no significant differences between pretreatment with EPO or application of IPC. PMID:26866008

  3. Renal protective effects of erythropoietin on ischemic reperfusion injury.

    PubMed

    Moriyama, Manabu T; Tanaka, Tatsuro; Morita, Nobuyo; Ishii, Takeo; Chikazawa, Ippei; Suga, Kodai; Miyazawa, Katsuhito; Suzuki, Koji

    2010-01-01

    enzymes, which had also shown increases in the serum as well as the occurrence of renal dysfunction, showed clear decreases in the serum, even though changes with a significant difference were not observed in the rhEPO administration group. The active oxygen did not show changes before and after ischemia-reperfusion nor changes due to the rhEPO administration. When examining the status of apoptosis in the tissues, apoptosis was shown to be inhibited due to the rhEPO administration. It is believed that the main preservation effects of rhEPO are the elimination of cytopathy/cell death, as derived from the resulting ischemic condition that extends to the target organ before ischemia occurs. In this examination, no direct effects of rhEPO administration on the emergence of active oxygen were observed. It is therefore suggested that there is a possibility of preserving the renal function in marginal donors with a longer agonal stage by effectively using rhEPO. PMID:20525439

  4. Macrophage-derived Lipocalin-2 contributes to ischemic resistance mechanisms by protecting from renal injury

    PubMed Central

    Jung, Michaela; Brüne, Bernhard; Hotter, Georgina; Sola, Anna

    2016-01-01

    Renal ischemia-reperfusion injury triggers an inflammatory response associated to infiltrating macrophages which determines the further outcome of disease. Brown Norway rats are known to show endogenous resistance to ischemia-induced renal damage. By contrast, Sprague Dawley rats exhibit a higher susceptibility to ischemic injury. In order to ascertain cytoprotective mechanisms, we focused on the implication of lipocalin-2 protein in main resistance mechanisms in renal ischemia/reperfusion injury by using adoptive macrophage administration, genetically modified ex vivo either to overexpress or to knockdown lipocalin-2. In vitro experiments with bone marrow-derived macrophages both from Brown Norway rats and from Sprague Dawley rats under hypoxic conditions showed endogenous differences regarding cytokine and lipocalin-2 expression profile in the two strains. Most interestingly, we observed that macrophages of the resistant strain express significantly more lipocalin-2. In vivo studies showed that tubular epithelial cell apoptosis and renal injury significantly increased and reparative markers decreased in Brown Norway rats after injection of lipocalin-2-knockdown macrophages, while the administration of lipocalin-2-overexpressing cells significantly decreased Sprague Dawley susceptibility. These data point to a crucial role of macrophage-derived lipocalin-2 in endogenous cytoprotective mechanisms. We conclude that expression of lipocalin-2 in tissue-infiltrating macrophages is pivotal for kidney-intrinsic cytoprotective pathways during ischemia reperfusion injury. PMID:26911537

  5. Targeted deletion of p53 in the proximal tubule prevents ischemic renal injury.

    PubMed

    Ying, Yuan; Kim, Jinu; Westphal, Sherry N; Long, Kelly E; Padanilam, Babu J

    2014-12-01

    The contribution of p53 to kidney dysfunction, inflammation, and tubular cell death, hallmark features of ischemic renal injury (IRI), remains undefined. Here, we studied the role of proximal tubule cell (PTC)-specific p53 activation on the short- and long-term consequences of renal ischemia/reperfusion injury in mice. After IRI, mice with PTC-specific deletion of p53 (p53 knockout [KO]) had diminished whole-kidney expression levels of p53 and its target genes, improved renal function, which was shown by decreased plasma levels of creatinine and BUN, and attenuated renal histologic damage, oxidative stress, and infiltration of neutrophils and macrophages compared with wild-type mice. Notably, necrotic cell death was attenuated in p53 KO ischemic kidneys as well as oxidant-injured p53-deficient primary PTCs and pifithrin-α-treated PTC lines. Reduced oxidative stress and diminished expression of PARP1 and Bax in p53 KO ischemic kidneys may account for the decreased necrosis. Apoptosis and expression of proapoptotic p53 targets, including Bid and Siva, were also significantly reduced, and cell cycle arrest at the G2/M phase was attenuated in p53 KO ischemic kidneys. Furthermore, IRI-induced activation of TGF-β and the long-term development of inflammation and interstitial fibrosis were significantly reduced in p53 KO mice. In conclusion, specific deletion of p53 in the PTC protects kidneys from functional and histologic deterioration after IRI by decreasing necrosis, apoptosis, and inflammation and modulates the long-term sequelae of IRI by preventing interstitial fibrogenesis. PMID:24854277

  6. Molecular Mechanisms of Renal Ischemic Conditioning Strategies.

    PubMed

    Kierulf-Lassen, Casper; Nieuwenhuijs-Moeke, Gertrude J; Krogstrup, Nicoline V; Oltean, Mihai; Jespersen, Bente; Dor, Frank J M F

    2015-01-01

    Ischemia-reperfusion injury is the leading cause of acute kidney injury in a variety of clinical settings such as renal transplantation and hypovolemic and/or septic shock. Strategies to reduce ischemia-reperfusion injury are obviously clinically relevant. Ischemic conditioning is an inherent part of the renal defense mechanism against ischemia and can be triggered by short periods of intermittent ischemia and reperfusion. Understanding the signaling transduction pathways of renal ischemic conditioning can promote further clinical translation and pharmacological advancements in this era. This review summarizes research on the molecular mechanisms underlying both local and remote ischemic pre-, per- and postconditioning of the kidney. The different types of conditioning strategies in the kidney recruit similar powerful pro-survival mechanisms. Likewise, renal ischemic conditioning mobilizes many of the same protective signaling pathways as in other organs, but differences are recognized. PMID:26330099

  7. Necroptosis and parthanatos are involved in remote lung injury after receiving ischemic renal allografts in rats.

    PubMed

    Zhao, Hailin; Ning, Jiaolin; Lemaire, Alexandre; Koumpa, Foteini-Stefania; Sun, James J; Fung, Anthony; Gu, Jianteng; Yi, Bin; Lu, Kaizhi; Ma, Daqing

    2015-04-01

    Early renal graft injury could result in remote pulmonary injury due to kidney-lung cross talk. Here we studied the possible role of regulated necrosis in remote lung injury in a rat allogeneic transplantation model. In vitro, human lung epithelial cell A549 was challenged with TNF-α and conditioned medium from human kidney proximal tubular cells (HK-2) after hypothermia-hypoxia insults. In vivo, the Brown-Norway rat renal grafts were extracted and stored in 4 °C Soltran preserving solution for up to 24 h and transplanted into Lewis rat recipients, and the lungs were harvested on day 1 and day 4 after grafting for further analysis. Ischemia-reperfusion injury in the renal allograft caused pulmonary injury following engraftment. PARP-1 (marker for parthanatos) and receptor interacting protein kinase 1 (Rip1) and Rip3 (markers for necroptosis) expression was significantly enhanced in the lung. TUNEL assays showed increased cell death of lung cells. This was significantly reduced after treatment with necrostatin-1 (nec-1) or/and 3-aminobenzamide (3-AB). Acute immune rejection exacerbated the remote lung injury and 3-AB or/and Nec-1 combined with cyclosporine A conferred optimal lung protection. Thus, renal graft injury triggered remote lung injury, likely through regulated necrosis. This study could provide the molecular basis for combination therapy targeting both pathways of regulated necrosis to treat such complications after renal transplantation. PMID:25517913

  8. Transglutaminase 2 gene ablation protects against renal ischemic injury by blocking constant NF-{kappa}B activation

    SciTech Connect

    Kim, Dae-Seok; Kim, Bora; Tahk, Hongmin; Kim, Dong-Hyun; Ahn, Eu-Ree; Choi, Changsun; Jeon, Yoon; Park, Seo Young; Lee, Ho; Oh, Seung Hyun; Kim, Soo-Youl

    2010-12-17

    Research highlights: {yields} No acute renal tubular necrotic lesions were found in TGase2{sup -/-} mice with ischemic kidney injury. {yields} NF-{kappa}B activation is reduced in TGase2{sup -/-} mice with ischemic kidney injury. {yields} Hypoxic stress did not increase NF-{kappa}B activity in MEFs from TGase2{sup -/-} mice. {yields} COX-2 induction is suppressed in TGase2{sup -/-} mice with ischemic kidney injury. -- Abstract: Transglutaminase 2 knockout (TGase2{sup -/-}) mice show significantly reduced inflammation with decreased myofibroblasts in a unilateral ureteral obstruction (UUO) model, but the mechanism remains to be clarified. Nuclear factor-{kappa}B (NF-{kappa}B) activation plays a major role in the progression of inflammation in an obstructive nephropathy model. However, the key factors extending the duration of NF-{kappa}B activation in UUO are not known. In several inflammatory diseases, we and others recently found that TGase 2 plays a key role in extending NF-{kappa}B activation, which contributes to the pathogenesis of disease. In the current study, we found that NF-{kappa}B activity in mouse embryogenic fibroblasts (MEFs) from TGase2{sup -/-} mice remained at the control level while the NF-{kappa}B activity of wild-type (WT) MEFs was highly increased under hypoxic stress. Using the obstructive nephropathy model, we found that NF-{kappa}B activity remained at the control level in TGase2{sup -/-} mouse kidney tissues, as measured by COX-2 expression, but was highly increased in WT tissues. We conclude that TGase 2 gene ablation reduces the duration of NF-{kappa}B activation in ischemic injury.

  9. No Effect of Remote Ischemic Conditioning Strategies on Recovery from Renal Ischemia-Reperfusion Injury and Protective Molecular Mediators

    PubMed Central

    Kierulf-Lassen, Casper; Kristensen, Marie Louise Vindvad; Birn, Henrik; Jespersen, Bente; Nørregaard, Rikke

    2015-01-01

    Ischemia-reperfusion injury (IRI) is the major cause of acute kidney injury. Remote ischemic conditioning (rIC) performed as brief intermittent sub-lethal ischemia and reperfusion episodes in a distant organ may protect the kidney against IRI. Here we investigated the renal effects of rIC applied either prior to (remote ischemic preconditioning; rIPC) or during (remote ischemic perconditioning; rIPerC) sustained ischemic kidney injury in rats. The effects were evaluated as differences in creatinine clearance (CrCl) rate, tissue tubular damage marker expression, and potential kidney recovery mediators. One week after undergoing right-sided nephrectomy, rats were randomly divided into four groups: sham (n = 7), ischemia and reperfusion (IR; n = 10), IR+rIPC (n = 10), and IR+rIPerC (n = 10). The rIC was performed as four repeated episodes of 5-minute clamping of the infrarenal aorta followed by 5-minute release either before or during 37 minutes of left renal artery clamping representing the IRI. Urine and blood were sampled prior to ischemia as well as 3 and 7 days after reperfusion. The kidney was harvested for mRNA and protein isolation. Seven days after IRI, the CrCl change from baseline values was similar in the IR (δ: 0.74 mL/min/kg [-0.45 to 1.94]), IR+rIPC (δ: 0.21 mL/min/kg [-0.75 to 1.17], p > 0.9999), and IR+rIPerC (δ: 0.41 mL/min/kg [-0.43 to 1.25], p > 0.9999) groups. Kidney function recovery was associated with a significant up-regulation of phosphorylated protein kinase B (pAkt), extracellular regulated kinase 1/2 (pERK1/2), and heat shock proteins (HSPs) pHSP27, HSP32, and HSP70, but rIC was not associated with any significant differences in tubular damage, inflammatory, or fibrosis marker expression. In our study, rIC did not protect the kidney against IRI. However, on days 3–7 after IRI, all groups recovered renal function. This was associated with pAkt and pERK1/2 up-regulation and increased HSP expression at day 7. PMID:26720280

  10. No Effect of Remote Ischemic Conditioning Strategies on Recovery from Renal Ischemia-Reperfusion Injury and Protective Molecular Mediators.

    PubMed

    Kierulf-Lassen, Casper; Kristensen, Marie Louise Vindvad; Birn, Henrik; Jespersen, Bente; Nørregaard, Rikke

    2015-01-01

    Ischemia-reperfusion injury (IRI) is the major cause of acute kidney injury. Remote ischemic conditioning (rIC) performed as brief intermittent sub-lethal ischemia and reperfusion episodes in a distant organ may protect the kidney against IRI. Here we investigated the renal effects of rIC applied either prior to (remote ischemic preconditioning; rIPC) or during (remote ischemic perconditioning; rIPerC) sustained ischemic kidney injury in rats. The effects were evaluated as differences in creatinine clearance (CrCl) rate, tissue tubular damage marker expression, and potential kidney recovery mediators. One week after undergoing right-sided nephrectomy, rats were randomly divided into four groups: sham (n = 7), ischemia and reperfusion (IR; n = 10), IR+rIPC (n = 10), and IR+rIPerC (n = 10). The rIC was performed as four repeated episodes of 5-minute clamping of the infrarenal aorta followed by 5-minute release either before or during 37 minutes of left renal artery clamping representing the IRI. Urine and blood were sampled prior to ischemia as well as 3 and 7 days after reperfusion. The kidney was harvested for mRNA and protein isolation. Seven days after IRI, the CrCl change from baseline values was similar in the IR (δ: 0.74 mL/min/kg [-0.45 to 1.94]), IR+rIPC (δ: 0.21 mL/min/kg [-0.75 to 1.17], p > 0.9999), and IR+rIPerC (δ: 0.41 mL/min/kg [-0.43 to 1.25], p > 0.9999) groups. Kidney function recovery was associated with a significant up-regulation of phosphorylated protein kinase B (pAkt), extracellular regulated kinase 1/2 (pERK1/2), and heat shock proteins (HSPs) pHSP27, HSP32, and HSP70, but rIC was not associated with any significant differences in tubular damage, inflammatory, or fibrosis marker expression. In our study, rIC did not protect the kidney against IRI. However, on days 3-7 after IRI, all groups recovered renal function. This was associated with pAkt and pERK1/2 up-regulation and increased HSP expression at day 7. PMID:26720280

  11. Transcriptome Analysis of Renal Ischemia/Reperfusion Injury and Its Modulation by Ischemic Pre-Conditioning or Hemin Treatment

    PubMed Central

    Amano, Mariane Tami; Gonçalves, Giselle Martins; Hyane, Meire Ioshie; Cenedeze, Marcos Antonio; Renesto, Paulo Guilherme; Pacheco-Silva, Alvaro; Moreira-Filho, Carlos Alberto; Câmara, Niels Olsen Saraiva

    2012-01-01

    Ischemia/reperfusion injury (IRI) is a leading cause of acute renal failure. The definition of the molecular mechanisms involved in renal IRI and counter protection promoted by ischemic pre-conditioning (IPC) or Hemin treatment is an important milestone that needs to be accomplished in this research area. We examined, through an oligonucleotide microarray protocol, the renal differential transcriptome profiles of mice submitted to IRI, IPC and Hemin treatment. After identifying the profiles of differentially expressed genes observed for each comparison, we carried out functional enrichment analysis to reveal transcripts putatively involved in potential relevant biological processes and signaling pathways. The most relevant processes found in these comparisons were stress, apoptosis, cell differentiation, angiogenesis, focal adhesion, ECM-receptor interaction, ion transport, angiogenesis, mitosis and cell cycle, inflammatory response, olfactory transduction and regulation of actin cytoskeleton. In addition, the most important overrepresented pathways were MAPK, ErbB, JAK/STAT, Toll and Nod like receptors, Angiotensin II, Arachidonic acid metabolism, Wnt and coagulation cascade. Also, new insights were gained about the underlying protection mechanisms against renal IRI promoted by IPC and Hemin treatment. Venn diagram analysis allowed us to uncover common and exclusively differentially expressed genes between these two protective maneuvers, underscoring potential common and exclusive biological functions regulated in each case. In summary, IPC exclusively regulated the expression of genes belonging to stress, protein modification and apoptosis, highlighting the role of IPC in controlling exacerbated stress response. Treatment with the Hmox1 inducer Hemin, in turn, exclusively regulated the expression of genes associated with cell differentiation, metabolic pathways, cell cycle, mitosis, development, regulation of actin cytoskeleton and arachidonic acid metabolism

  12. Renoprotective Mechanism of Remote Ischemic Preconditioning Based on Transcriptomic Analysis in a Porcine Renal Ischemia Reperfusion Injury Model

    PubMed Central

    Kim, Sook Young; Cho, Young In; Lee, Kwang Suk; Kim, Kwang Hyun; Yang, Seung Choul; Han, Woong Kyu

    2015-01-01

    Ischemic preconditioning (IPC) is a well-known phenomenon in which tissues are exposed to a brief period of ischemia prior to a longer ischemic event. This technique produces tissue tolerance to ischemia reperfusion injury (IRI). Currently, IPC’s mechanism of action is poorly understood. Using a porcine single kidney model, we performed remote IPC with renal IRI and evaluated the IPC mechanism of action. Following left nephrectomy, 15 female Yorkshire pigs were divided into three groups: no IPC and 90 minutes of warm ischemia (control), remote IPC immediately followed by 90 minutes of warm ischemia (rIPCe), and remote IPC with 90 minutes of warm ischemia performed 24 hours later (rIPCl). Differential gene expression analysis was performed using a porcine-specific microarray. The microarray analysis of porcine renal tissues identified 1,053 differentially expressed probes in preconditioned pigs. Among these, 179 genes had altered expression in both the rIPCe and rIPCl groups. The genes were largely related to oxidation reduction, apoptosis, and inflammatory response. In the rIPCl group, an additional 848 genes had altered expression levels. These genes were primarily related to immune response and inflammation, including those coding for cytokines and cytokine receptors and those that play roles in the complement system and coagulation cascade. In the complement system, the membrane attack complex was determined to be sublytic, because it colocalized with phosphorylated extracellular signal-regulated kinase. Furthermore, alpha 2 macroglobulin, tissue plasminogen activator, uterine plasmin trypsin inhibitor, and arginase-1 mRNA levels were elevated in the rIPCl group. These findings indicate that remote IPC produces renoprotective effects through multiple mechanisms, and these effects develop over a long timeframe rather than immediately following IPC. PMID:26489007

  13. Ischemic preconditioning protects against ischemic brain injury

    PubMed Central

    Ma, Xiao-meng; Liu, Mei; Liu, Ying-ying; Ma, Li-li; Jiang, Ying; Chen, Xiao-hong

    2016-01-01

    In this study, we hypothesized that an increase in integrin αvβ3 and its co-activator vascular endothelial growth factor play important neuroprotective roles in ischemic injury. We performed ischemic preconditioning with bilateral common carotid artery occlusion for 5 minutes in C57BL/6J mice. This was followed by ischemic injury with bilateral common carotid artery occlusion for 30 minutes. The time interval between ischemic preconditioning and lethal ischemia was 48 hours. Histopathological analysis showed that ischemic preconditioning substantially diminished damage to neurons in the hippocampus 7 days after ischemia. Evans Blue dye assay showed that ischemic preconditioning reduced damage to the blood-brain barrier 24 hours after ischemia. This demonstrates the neuroprotective effect of ischemic preconditioning. Western blot assay revealed a significant reduction in protein levels of integrin αvβ3, vascular endothelial growth factor and its receptor in mice given ischemic preconditioning compared with mice not given ischemic preconditioning 24 hours after ischemia. These findings suggest that the neuroprotective effect of ischemic preconditioning is associated with lower integrin αvβ3 and vascular endothelial growth factor levels in the brain following ischemia. PMID:27335560

  14. Ischemic preconditioning protects against ischemic brain injury.

    PubMed

    Ma, Xiao-Meng; Liu, Mei; Liu, Ying-Ying; Ma, Li-Li; Jiang, Ying; Chen, Xiao-Hong

    2016-05-01

    In this study, we hypothesized that an increase in integrin αvβ3 and its co-activator vascular endothelial growth factor play important neuroprotective roles in ischemic injury. We performed ischemic preconditioning with bilateral common carotid artery occlusion for 5 minutes in C57BL/6J mice. This was followed by ischemic injury with bilateral common carotid artery occlusion for 30 minutes. The time interval between ischemic preconditioning and lethal ischemia was 48 hours. Histopathological analysis showed that ischemic preconditioning substantially diminished damage to neurons in the hippocampus 7 days after ischemia. Evans Blue dye assay showed that ischemic preconditioning reduced damage to the blood-brain barrier 24 hours after ischemia. This demonstrates the neuroprotective effect of ischemic preconditioning. Western blot assay revealed a significant reduction in protein levels of integrin αvβ3, vascular endothelial growth factor and its receptor in mice given ischemic preconditioning compared with mice not given ischemic preconditioning 24 hours after ischemia. These findings suggest that the neuroprotective effect of ischemic preconditioning is associated with lower integrin αvβ3 and vascular endothelial growth factor levels in the brain following ischemia. PMID:27335560

  15. Ischemic tissue injury.

    PubMed Central

    Jennings, R. B.; Ganote, C. E.; Reimer, K. A.

    1975-01-01

    The subendocardial to subepicardial gradient in the severity of ischemia following acute coronary occlusion is described. The effects of mild, moderate, and severe ischemia on cell structure and function are compared in summary form, and special attention is given to the effects of severe ischemia on myocardial cells. The characteristics of reversible and irreversible ischemic injury are defined in biologic terms. The failure of cell volume regulation in cells which have entered an irreversible state of ischemic injury is demonstrated by the use of free-hand slices in vitro. Irreversibility is associated with structural defects in the plasma membrane and is reflected in an increased slice inulin-diffusible space, increased slice H2O and Na+ content, and failure of the tissue to maintain the high K+ and Mg2+ levels characteristic of normal left ventricular myocardium. Defective cell membrane function is an early feature of irreversible ischemic injury and may be a primary event in the genesis of the irreversible state. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:1180331

  16. Role of Cystathionine Gamma-Lyase in Immediate Renal Impairment and Inflammatory Response in Acute Ischemic Kidney Injury

    PubMed Central

    Markó, Lajos; Szijártó, István A.; Filipovic, Milos R.; Kaßmann, Mario; Balogh, András; Park, Joon-Keun; Przybyl, Lukasz; N’diaye, Gabriele; Krämer, Stephanie; Anders, Juliane; Ishii, Isao; Müller, Dominik N.; Gollasch, Maik

    2016-01-01

    Hydrogen sulfide (H2S) is known to act protectively during renal ischemia/reperfusion injury (IRI). However, the role of the endogenous H2S in acute kidney injury (AKI) is largely unclear. Here, we analyzed the role of cystathionine gamma-lyase (CTH) in acute renal IRI using CTH-deficient (Cth−/−) mice whose renal H2S levels were approximately 50% of control (wild-type) mice. Although levels of serum creatinine and renal expression of AKI marker proteins were equivalent between Cth−/− and control mice, histological analysis revealed that IRI caused less renal tubular damage in Cth−/− mice. Flow cytometric analysis revealed that renal population of infiltrated granulocytes/macrophages was equivalent in these mice. However, renal expression levels of certain inflammatory cytokines/adhesion molecules believed to play a role in IRI were found to be lower after IRI only in Cth−/− mice. Our results indicate that the systemic CTH loss does not deteriorate but rather ameliorates the immediate AKI outcome probably due to reduced inflammatory responses in the kidney. The renal expression of CTH and other H2S-producing enzymes was markedly suppressed after IRI, which could be an integrated adaptive response for renal cell protection. PMID:27273292

  17. Role of Cystathionine Gamma-Lyase in Immediate Renal Impairment and Inflammatory Response in Acute Ischemic Kidney Injury.

    PubMed

    Markó, Lajos; Szijártó, István A; Filipovic, Milos R; Kaßmann, Mario; Balogh, András; Park, Joon-Keun; Przybyl, Lukasz; N'diaye, Gabriele; Krämer, Stephanie; Anders, Juliane; Ishii, Isao; Müller, Dominik N; Gollasch, Maik

    2016-01-01

    Hydrogen sulfide (H2S) is known to act protectively during renal ischemia/reperfusion injury (IRI). However, the role of the endogenous H2S in acute kidney injury (AKI) is largely unclear. Here, we analyzed the role of cystathionine gamma-lyase (CTH) in acute renal IRI using CTH-deficient (Cth(-/-)) mice whose renal H2S levels were approximately 50% of control (wild-type) mice. Although levels of serum creatinine and renal expression of AKI marker proteins were equivalent between Cth(-/-) and control mice, histological analysis revealed that IRI caused less renal tubular damage in Cth(-/-) mice. Flow cytometric analysis revealed that renal population of infiltrated granulocytes/macrophages was equivalent in these mice. However, renal expression levels of certain inflammatory cytokines/adhesion molecules believed to play a role in IRI were found to be lower after IRI only in Cth(-/-) mice. Our results indicate that the systemic CTH loss does not deteriorate but rather ameliorates the immediate AKI outcome probably due to reduced inflammatory responses in the kidney. The renal expression of CTH and other H2S-producing enzymes was markedly suppressed after IRI, which could be an integrated adaptive response for renal cell protection. PMID:27273292

  18. Preclinical Evidence for the Efficacy of Ischemic Postconditioning against Renal Ischemia-Reperfusion Injury, a Systematic Review and Meta-Analysis

    PubMed Central

    Jonker, Simone J.; Menting, Theo P.; Warlé, Michiel C.; Ritskes-Hoitinga, Merel; Wever, Kimberley E.

    2016-01-01

    Background Renal ischemia-reperfusion injury (IRI) is a major cause of kidney damage after e.g. renal surgery and transplantation. Ischemic postconditioning (IPoC) is a promising treatment strategy for renal IRI, but early clinical trials have not yet replicated the promising results found in animal studies. Method We present a systematic review, quality assessment and meta-analysis of the preclinical evidence for renal IPoC, and identify factors which modify its efficacy. Results We identified 39 publications studying >250 control animals undergoing renal IRI only and >290 animals undergoing renal IRI and IPoC. Healthy, male rats undergoing warm ischemia were used in the vast majority of studies. Four studies applied remote IPoC, all others used local IPoC. Meta-analysis showed that both local and remote IPoC ameliorated renal damage after IRI for the outcome measures serum creatinine, blood urea nitrogen and renal histology. Subgroup analysis indicated that IPoC efficacy increased with the duration of index ischemia. Measures to reduce bias were insufficiently reported. Conclusion High efficacy of IPoC is observed in animal models, but factors pertaining to the internal and external validity of these studies may hamper the translation of IPoC to the clinical setting. The external validity of future animal studies should be increased by including females, comorbid animals, and transplantation models, in order to better inform clinical trial design. The severity of renal damage should be taken into account in the design and analysis of future clinical trials. PMID:26963819

  19. Meclofenamate elicits a nephropreventing effect in a rat model of ischemic acute kidney injury by suppressing indoxyl sulfate production and restoring renal organic anion transporters

    PubMed Central

    Saigo, Chika; Nomura, Yui; Yamamoto, Yuko; Sagata, Masataka; Matsunaga, Rika; Jono, Hirofumi; Nishi, Kazuhiko; Saito, Hideyuki

    2014-01-01

    Indoxyl sulfate (IS), a putative low-molecular weight uremic toxin, is excreted in the urine under normal kidney function, but is retained in the circulation and tissues during renal dysfunction in acute kidney injury and chronic kidney disease. IS, which is one of the most potent inducers of oxidative stress in the kidney and cardiovascular system, is enzymatically produced in the liver from indole by cytochrome P450-mediated hydroxylation to indoxyl, followed by sulfotransferase-mediated sulfate conjugation. We used rat liver S9 fraction to identify inhibitors of IS production. After testing several compounds, including phytochemical polyphenols, we identified meclofenamate as a potent inhibitor of IS production with an apparent IC50 value of 1.34 μM. Ischemia/reperfusion (I/R) of rat kidney caused a marked elevation in the serum IS concentration 48 hours after surgery. However, intravenous administration of meclofenamate (10 mg/kg) significantly suppressed this increase in the serum level of IS. Moreover, IS concentrations in both kidney and liver were dramatically elevated by renal I/R treatment, but this increase was blocked by meclofenamate. Serum creatinine and blood urea nitrogen were markedly elevated in rats after renal I/R treatment, but these increases were significantly restored by administration of meclofenamate. Renal expression of both basolateral membrane-localized organic anion transporters rOAT1 and rOAT3 was downregulated by I/R treatment. However, expression of rOAT1 and rOAT3 recovered after administration of meclofenamate, which is associated with the inhibition of I/R-evoked elevation of prostaglandin E2. Our results suggest that meclofenamate inhibits hepatic sulfotransferase-mediated production of IS, thereby suppressing serum and renal accumulation of IS. Meclofenamate also prevents the prostaglandin E2-dependent downregulation of rOAT1 and rOAT3 expression. In conclusion, meclofenamate was found to elicit a nephropreventive effect in

  20. Meclofenamate elicits a nephropreventing effect in a rat model of ischemic acute kidney injury by suppressing indoxyl sulfate production and restoring renal organic anion transporters.

    PubMed

    Saigo, Chika; Nomura, Yui; Yamamoto, Yuko; Sagata, Masataka; Matsunaga, Rika; Jono, Hirofumi; Nishi, Kazuhiko; Saito, Hideyuki

    2014-01-01

    Indoxyl sulfate (IS), a putative low-molecular weight uremic toxin, is excreted in the urine under normal kidney function, but is retained in the circulation and tissues during renal dysfunction in acute kidney injury and chronic kidney disease. IS, which is one of the most potent inducers of oxidative stress in the kidney and cardiovascular system, is enzymatically produced in the liver from indole by cytochrome P450-mediated hydroxylation to indoxyl, followed by sulfotransferase-mediated sulfate conjugation. We used rat liver S9 fraction to identify inhibitors of IS production. After testing several compounds, including phytochemical polyphenols, we identified meclofenamate as a potent inhibitor of IS production with an apparent IC50 value of 1.34 μM. Ischemia/reperfusion (I/R) of rat kidney caused a marked elevation in the serum IS concentration 48 hours after surgery. However, intravenous administration of meclofenamate (10 mg/kg) significantly suppressed this increase in the serum level of IS. Moreover, IS concentrations in both kidney and liver were dramatically elevated by renal I/R treatment, but this increase was blocked by meclofenamate. Serum creatinine and blood urea nitrogen were markedly elevated in rats after renal I/R treatment, but these increases were significantly restored by administration of meclofenamate. Renal expression of both basolateral membrane-localized organic anion transporters rOAT1 and rOAT3 was downregulated by I/R treatment. However, expression of rOAT1 and rOAT3 recovered after administration of meclofenamate, which is associated with the inhibition of I/R-evoked elevation of prostaglandin E2. Our results suggest that meclofenamate inhibits hepatic sulfotransferase-mediated production of IS, thereby suppressing serum and renal accumulation of IS. Meclofenamate also prevents the prostaglandin E2-dependent downregulation of rOAT1 and rOAT3 expression. In conclusion, meclofenamate was found to elicit a nephropreventive effect in

  1. [Uncaria tomentosa and acute ischemic kidney injury in rats].

    PubMed

    de Fátima Fernandes Vattimo, Maria; da Silva, Natalia Oliveira

    2011-03-01

    The objective of this study was to evaluate the renoprotective effects of Uncaria Tomentosa (cat's claw) on ischemic acute kidney injury induced by renal clamping in rats. The hypoxia and hypoperfusion increase the production of reactive species already present in the inflammatory process. Results showed that the renal function evaluated by creatinine clearance, the urinary excretion of peroxides and malondealdehyde indexes demonstrated that UT induced renoprotection, probably related to its antioxidant activities. PMID:21445508

  2. Renal injury in sport.

    PubMed

    Holmes, F Clarke; Hunt, Jeremy J; Sevier, Thomas L

    2003-04-01

    Hematuria is the most common presenting sign of renal injury. Its presence in athletes may indicate a benign entity such as exercise-induced hematuria or a more serious injury in the presence of trauma. Exercise-induced hematuria can originate in the kidney, bladder, urethra, or prostate. The type of activity, as well as activity duration and intensity, contributes to its development. A wide differential diagnosis must be considered if hematuria persists longer than 24 to 72 hours. Trauma to the kidney can occur from a direct blow or deceleration; contact and collision sports are most commonly involved. Fortunately, most sports-related renal trauma is mild, and can be managed expectantly. A sporting injury rarely results in nephrectomy. Determining return to play for the athlete with a single kidney remains a controversial issue that requires patient education and an individualized approach. PMID:12831667

  3. Ischemic Acute Kidney Injury Perturbs Homeostasis of Serine Enantiomers in the Body Fluid in Mice: Early Detection of Renal Dysfunction Using the Ratio of Serine Enantiomers

    PubMed Central

    Sasabe, Jumpei; Suzuki, Masataka; Miyoshi, Yurika; Tojo, Yosuke; Okamura, Chieko; Ito, Sonomi; Konno, Ryuichi; Mita, Masashi; Hamase, Kenji; Aiso, Sadakazu

    2014-01-01

    The imbalance of blood and urine amino acids in renal failure has been studied mostly without chiral separation. Although a few reports have shown the presence of D-serine, an enantiomer of L-serine, in the serum of patients with severe renal failure, it has remained uncertain how serine enantiomers are deranged in the development of renal failure. In the present study, we have monitored serine enantiomers using a two-dimensional HPLC system in the serum and urine of mice after renal ischemia-reperfusion injury (IRI), known as a mouse model of acute kidney injury. In the serum, the level of D-serine gradually increased after renal IRI in parallel with that of creatinine, whereas the L-serine level decreased sharply in the early phase after IRI. The increase of D-serine was suppressed in part by genetic inactivation of a D-serine-degrading enzyme, D-amino acid oxidase (DAO), but not by disruption of its synthetic enzyme, serine racemase, in mice. Renal DAO activity was detected exclusively in proximal tubules, and IRI reduced the number of DAO-positive tubules. On the other hand, in the urine, D-serine was excreted at a rate nearly triple that of L-serine in mice with sham operations, indicating that little D-serine was reabsorbed while most L-serine was reabsorbed in physiological conditions. IRI significantly reduced the ratio of urinary D−/L-serine from 2.82±0.18 to 1.10±0.26 in the early phase and kept the ratio lower than 0.5 thereafter. The urinary D−/L-serine ratio can detect renal ischemia earlier than kidney injury molecule-1 (KIM-1) or neutrophil gelatinase-associated lipocalin (NGAL) in the urine, and more sensitively than creatinine, cystatin C, or the ratio of D−/L-serine in the serum. Our findings provide a novel understanding of the imbalance of amino acids in renal failure and offer a potential new biomarker for an early detection of acute kidney injury. PMID:24489731

  4. Role of mitochondria in ischemic acute renal failure.

    PubMed

    Burke, T J; Wilson, D R; Levi, M; Gordon, J A; Arnold, P E; Schrier, R W

    1983-01-01

    Ischemic ARF is characterized by progressive mitochondrial accumulation of Ca++ which is inversely correlated with the level of oxidative phosphorylation. At least two possibilities exist which would be compatible with these data 1) depressed respiration leads to Ca++ accumulation or 2) increased mitochondrial Ca++ leads to reduced mitochondrial respiration. We favor the latter hypothesis for the reasons outlined above; furthermore, this conclusion is supported by the observations of Lehninger, made some 20 years ago: first, that either oxidative phosphorylation or mitochondrial Ca++ accumulation can be accomplished by intact mitochondria but that these events cannot occur simultaneously and second, that Ca++ accumulation takes precedence over oxidative phosphorylation. Our observation made during post-ischemic reflow that mitochondrial Ca++ accumulation occurs to a significant degree, strongly suggest a potential role for mitochondrial Ca++ overload in the pathogenesis of ARF. Nevertheless, this is not an irreversible pathogenetic process. Clearly, impermeant solutes, vasodilators and Ca++ membrane blockers will alter the natural history of this injury and prevent the severity of the functional defect. A common mechanism of action may involve direct or indirect modification of cellular Ca++ overload in renal vascular and epithelial tissue. The vascular smooth muscle may then revert to a less constricted state with a subsequent more rapid recovery of renal blood flow and that the renal epithelial cell death may be minimized thereby reducing tubular obstruction. PMID:6883804

  5. Vitamin D deficiency aggravates ischemic acute kidney injury in rats

    PubMed Central

    de Bragança, Ana Carolina; Volpini, Rildo A; Canale, Daniele; Gonçalves, Janaína G; Shimizu, Maria Heloisa M; Sanches, Talita R; Seguro, Antonio C; Andrade, Lúcia

    2015-01-01

    Vitamin D deficiency (VDD) increases the risk of death in hospitalized patients. Renal ischemia/reperfusion injury (IRI) induces acute kidney injury (AKI), which activates cell cycle inhibitors, including p21, a cyclin-dependent kinase inhibitor and genomic target of 25-hydroxyvitamin D, which is in turn a potent immunomodulator with antiproliferative effects. In this study, we assess the impact of VDD in renal IRI. Wistar rats were divided into groups, each evaluated for 30 days: control (receiving a standard diet); VDD (receiving a vitamin D-free diet); IRI (receiving a standard diet and subjected to 45-min bilateral renal ischemia on day 28); and VDD + IRI (receiving a vitamin D-free diet and subjected to 45-min bilateral renal ischemia on day 28). At 48 h after IRI, animals were euthanized; blood, urine, and kidney tissue samples were collected. Compared with IRI rats, VDD + IRI rats showed a more severe decrease in glomerular filtration rate, greater urinary protein excretion, a higher kidney/body weight ratio and lower renal aquaporin 2 expression, as well as greater morphological damage, characterized by increased interstitial area and tubular necrosis. Our results suggest that the severity of tubular damage in IRI may be associated with downregulation of vitamin D receptors and p21. VDD increases renal inflammation, cell proliferation and cell injury in ischemic AKI. PMID:25780095

  6. Delivery of interleukin-10 via injectable hydrogels improves renal outcomes and reduces systemic inflammation following ischemic acute kidney injury in mice.

    PubMed

    Soranno, Danielle E; Rodell, Christopher B; Altmann, Christopher; Duplantis, Jane; Andres-Hernando, Ana; Burdick, Jason A; Faubel, Sarah

    2016-08-01

    Injectable hydrogels can be used to deliver drugs in situ over a sustained period of time. We hypothesized that sustained delivery of interleukin-10 (IL-10) following acute kidney injury (AKI) would mitigate the local and systemic proinflammatory cascade induced by AKI and reduce subsequent fibrosis. Wild-type C57BL/6 mice underwent ischemia-reperfusion AKI with avertin anesthesia. Three days later, mice were treated with either hyaluronic acid injectable hydrogel with or without IL-10, or IL-10 suspended in saline, injected under the capsule of the left kidney, or hydrogel with IL-10 injected subcutaneously. Untreated AKI served as controls. Serial in vivo optical imaging tracked the location and degradation of the hydrogel over time. Kidney function was assessed serially. Animals were killed 28 days following AKI and the following were evaluated: serum IL-6, lung inflammation, urine neutrophil gelatinase-associated lipocalin, and renal histology for fibroblast activity, collagen type III deposition and fibrosis via Picrosirius Red staining and second harmonic imaging. Our model shows persistent systemic inflammation, and renal inflammation and fibrosis 28 days following AKI. The hydrogels are biocompatible and reduced serum IL-6 and renal collagen type III 28 days following AKI even when delivered without IL-10. Treatment with IL-10 reduced renal and systemic inflammation, regardless of whether the IL-10 was delivered in a sustained manner via the injectable hydrogel under the left kidney capsule, as a bolus injection via saline under the left kidney capsule, or via the injectable hydrogel subcutaneously. Injectable hydrogels are suitable for local drug delivery following renal injury, are biocompatible, and help mitigate local and systemic inflammation. PMID:26962109

  7. Spectroscopic Monitoring of Kidney Tissue Ischemic Injury

    SciTech Connect

    Demos, S G; Fitzgerald, J T; Michalopoulou, A P; Troppmann, C

    2004-03-11

    Noninvasive evaluation of tissue viability of donor kidneys used for transplantation is an issue that current technology is not able to address. In this work, we explore optical spectroscopy for its potential to assess the degree of ischemic damage in kidney tissue. We hypothesized that ischemic damage to kidney tissue will give rise to changes in its optical properties which in turn may be used to asses the degree of tissue injury. The experimental results demonstrate that the autofluorescence intensity of the injured kidney is decreasing as a function of time exposed to ischemic injury. Changes were also observed in the NIR light scattering intensities most probably arising from changes due to injury and death of the tissue.

  8. Neutrophil gelatinase-associated lipocalin protects renal tubular epithelial cell in ischemic/reperfusion injury rats via apoptosis-regulating proteins.

    PubMed

    Gong, Li; Yu, Hua; ZhuGe, Yifeng; Yu, Qing

    2012-01-01

    We investigated the role of neutrophil gelatinase-associated lipocalin (NGAL) on renal tubular epithelial cell in the renal ischemia/reperfusion injury (IRI) rats. Male Sprague-Dawley rats were randomly assigned to three groups. The control group (n = 5) underwent left nephrectomy. The ischemia/reperfusion (I/R) + normal saline (NS) (n = 5) and I/R + NGAL groups (n = 5) were subjected to 45 min right renal ischemia followed by 48 h of reperfusion after left nephrectomy. The pathological changes of kidney tissues were investigated using hematoxylin-eosin staining; renal tubular epithelial cell apoptosis was detected using terminal dUTP nick-labeling method; expression of apoptosis-regulating protein Fas and Bcl-2 was measured using real-time polymerase chain reaction, Western blot, and immunohistochemical staining. Compared with I/R + NS group, kidney tissues from I/R + NGAL group revealed reduced histological damage and a decreased number of renal tubular epithelial cell apoptosis (9.2 ± 2.53 nuclei or 4.0 ± 0.7 per high-power field vs. 20.3 ± 3.7 nuclei or 8.1 ± 0.3 per high-power field); rats with NGAL showed downregulated fas mRNA (2.34 ± 0.51 vs. 6.84 ± 2.34), fas protein (0.65 ± 0.05 vs. 0.95 ± 0.08), and upregulated bcl-2 protein (0.33 ± 0.05 vs. 0.24 ± 0.03). The results had statistical significance (p < 0.05). We think NGAL could protect against renal IRI and might be related to decreasing tubular epithelial cell apoptosis via adjusting the expression of apoptosis-regulating proteins. PMID:22500534

  9. Microglia in ischemic brain injury

    PubMed Central

    Weinstein, Jonathan R; Koerner, Ines P; Möller, Thomas

    2010-01-01

    Microglia are resident CNS immune cells that are active sensors in healthy brain and versatile effectors under pathological conditions. Cerebral ischemia induces a robust neuroinflammatory response that includes marked changes in the gene-expression profile and phenotype of a variety of endogenous CNS cell types (astrocytes, neurons and microglia), as well as an influx of leukocytic cells (neutrophils, macrophages and T-cells) from the periphery. Many molecules and conditions can trigger a transformation of surveying microglia to microglia of an alerted or reactive state. Here we review recent developments in the literature that relate to microglial activation in the experimental setting of in vitro and in vivo ischemia. We also present new data from our own laboratory demonstrating the direct effects of in vitro ischemic conditions on the microglial phenotype and genomic profile. In particular, we focus on the role of specific molecular signaling systems, such as hypoxia inducible factor-1 and Toll-like receptor-4, in regulating the microglial response in this setting. We then review histological and novel radiological data that confirm a key role for microglial activation in the setting of ischemic stroke in humans. We also discuss recent progress in the pharmacologic and molecular targeting of microglia in acute ischemic stroke. Finally, we explore how recent studies on ischemic preconditioning have increased interest in pre-emptively targeting microglial activation in order to reduce stroke severity. PMID:20401171

  10. TNFR1-dependent pulmonary apoptosis during ischemic acute kidney injury

    PubMed Central

    White, Laura E.; Santora, Rachel J.; Cui, Yan; Moore, Frederick A.

    2012-01-01

    Despite advancements in renal replacement therapy, the mortality rate for acute kidney injury (AKI) remains unacceptably high, likely due to remote organ injury. Kidney ischemia-reperfusion injury (IRI) activates cellular and soluble mediators that incite a distinct pulmonary proinflammatory and proapoptotic response. Tumor necrosis factor receptor 1 (TNFR1) has been identified as a prominent death receptor activated in the lungs during ischemic AKI. We hypothesized that circulating TNF-α released from the postischemic kidney induces TNFR1-mediated pulmonary apoptosis, and we aimed to elucidate molecular pathways to programmed cell death. Using an established murine model of kidney IRI, we characterized the time course for increased circulatory and pulmonary TNF-α levels and measured concurrent upregulation of pulmonary TNFR1 expression. We then identified TNFR1-dependent pulmonary apoptosis after ischemic AKI using TNFR1−/− mice. Subsequent TNF-α signaling disruption with Etanercept implicated circulatory TNF-α as a key soluble mediator of pulmonary apoptosis and lung microvascular barrier dysfunction during ischemic AKI. We further elucidated pathways of TNFR1-mediated apoptosis with NF-κB (Complex I) and caspase-8 (Complex II) expression and discovered that TNFR1 proapoptotic signaling induces NF-κB activation. Additionally, inhibition of NF-κB (Complex I) resulted in a proapoptotic phenotype, lung barrier leak, and altered cellular flice inhibitory protein signaling independent of caspase-8 (Complex II) activation. Ischemic AKI activates soluble TNF-α and induces TNFR1-dependent pulmonary apoptosis through augmentation of the prosurvival and proapoptotic TNFR1 signaling pathway. Kidney-lung crosstalk after ischemic AKI represents a complex pathological process, yet focusing on specific biological pathways may yield potential future therapeutic targets. PMID:22728466

  11. Curcumin protects against ischemic spinal cord injury: The pathway effect.

    PubMed

    Zhang, Jinhua; Wei, Hao; Lin, Meimei; Chen, Chunmei; Wang, Chunhua; Liu, Maobai

    2013-12-25

    Inducible nitric oxide synthase and N-methyl-D-aspartate receptors have been shown to participate in nerve cell injury during spinal cord ischemia. This study observed a protective effect of curcumin on ischemic spinal cord injury. Models of spinal cord ischemia were established by ligating the lumbar artery from the left renal artery to the bifurcation of the abdominal aorta. At 24 hours after model establishment, the rats were intraperitoneally injected with curcumin. Reverse transcription-polymerase chain reaction and immunohistochemical results demonstrated that after spinal cord ischemia, inducible nitric oxide synthase and N-methyl-D-aspartate receptor mRNA and protein expression significantly increased. However, curcumin significantly decreased inducible nitric oxide synthase and N-methyl-D-aspartate receptor mRNA and protein expression in the ischemic spinal cord. Tarlov scale results showed that curcumin significantly improved motor function of the rat hind limb after spinal cord ischemia. The results demonstrate that curcumin exerts a neuroprotective fect against ischemic spinal cord injury by decreasing inducible nitric oxide synthase and N-methyl-D-aspartate receptor expression. PMID:25206661

  12. White matter injury in ischemic stroke.

    PubMed

    Wang, Yuan; Liu, Gang; Hong, Dandan; Chen, Fenghua; Ji, Xunming; Cao, Guodong

    2016-06-01

    Stroke is one of the major causes of disability and mortality worldwide. It is well known that ischemic stroke can cause gray matter injury. However, stroke also elicits profound white matter injury, a risk factor for higher stroke incidence and poor neurological outcomes. The majority of damage caused by stroke is located in subcortical regions and, remarkably, white matter occupies nearly half of the average infarct volume. Indeed, white matter is exquisitely vulnerable to ischemia and is often injured more severely than gray matter. Clinical symptoms related to white matter injury include cognitive dysfunction, emotional disorders, sensorimotor impairments, as well as urinary incontinence and pain, all of which are closely associated with destruction and remodeling of white matter connectivity. White matter injury can be noninvasively detected by MRI, which provides a three-dimensional assessment of its morphology, metabolism, and function. There is an urgent need for novel white matter therapies, as currently available strategies are limited to preclinical animal studies. Optimal protection against ischemic stroke will need to encompass the fortification of both gray and white matter. In this review, we discuss white matter injury after ischemic stroke, focusing on clinical features and tools, such as imaging, manifestation, and potential treatments. We also briefly discuss the pathophysiology of WMI and future research directions. PMID:27090751

  13. Susceptibility of the pancreas to ischemic injury in shock.

    PubMed Central

    Warshaw, A L; O'Hara, P J

    1978-01-01

    The pancreas, like the kidney, is highly vulnerable to ischemic necrosis. This form of pancreatic injury may express itself as prolonged hyperamylasemia with only minimal signs or symptoms of inflammation, or may produce severe pancreatitis followed by abscesses and death. Autopsy examination of patients dying after oligemic shock showed a 9% incidence of major pancreatic injury if there was not concomitant acute renal tubular necrosis (ATN), but a 50% incidence in those with ATN. Similarly, among patients dying after non-oligemic shock, 12% of those without ATN had major pancreatic injury but 35% with ATN also had pancreatic ischemic injury. Among 13 selected patients examined prospectively after being in shock, pancreatic injury was indicated by hyperamylasemia, hyperlipasemia, elevated amylase/creatinine clearance ratio, and elevated circulating isoamylases specifically of pancreatic origin. Four of the 13 had clinical manifestations of pancreatitis. Not only must shock be added to this list of causes of pancreatitis, but pancreatic ischemia due to hypoperfusion may also be the critical factor which causes the progression from edema to necrosis in other forms of pancreatitis, including those associated with alcohol and biliary disease. PMID:686887

  14. The Study of Pentoxifylline Drug Effects on Renal Apoptosis and BCL-2 Gene Expression Changes Following Ischemic Reperfusion Injury in Rat

    PubMed Central

    Hashemi, Mehrdad

    2014-01-01

    Ischemia Reperfusion injury is the tissue damage caused when blood supply returns to the tissue after a period of ischemia or lack of oxygen. In this study, the effect of pentoxyfylline on BCL-2 gene expression changes and cell injury in kidney of rat following Ischemia Reperfusion were evaluated. In this experimental study, 20 male wistar rats with average weight of 250-300 g were selected and then were accidently divided them on two tenth group of control and treatment groups. In the control group, celiotomy was performed by ventral midline incision. The left kidney was isolated, and then both the renal artery and vein were obstructed. After 60 minutes of warm ischemia, vessel obstruction resolved and the right kidney was removed. 72 hours after reperfusion, tissue samples were taken from left kidney for Tunel assay. We used quantitative real time PCR for detection of BCL-2 gene expression in treated groups and then compared them to control samples. In the treatment group, the cell death changes, showed lower level than the control group. The results also showed the BCL-2 gene expression was declined in ischemia group as campared to PNT drug group. The pentoxyfylline might have a role in control of apoptosis result from Ischemia- reperfusion and quantitative real-time PCR can be used as a direct method for detection BCL-2 gene expression in tested samples and normal samples. PMID:24734070

  15. Renal ischemia/reperfusion injury; from pathophysiology to treatment

    PubMed Central

    Malek, Maryam; Nematbakhsh, Mehdi

    2015-01-01

    Ischemia/reperfusion injury (IRI) is caused by a sudden temporary impairment of the blood flow to the particular organ. IRI usually is associated with a robust inflammatory and oxidative stress response to hypoxia and reperfusion which disturbs the organ function. Renal IR induced acute kidney injury (AKI) contributes to high morbidity and mortality rate in a wide range of injuries. Although the pathophysiology of IRI is not completely understood, several important mechanisms resulting in kidney failure have been mentioned. In ischemic kidney and subsequent of re-oxygenation, generation of reactive oxygen species (ROS) at reperfusion phase initiates a cascade of deleterious cellular responses leading to inflammation, cell death, and acute kidney failure. Better understanding of the cellular pathophysiological mechanisms underlying kidney injury will hopefully result in the design of more targeted therapies to prevent and treatment the injury. In this review, we summarize some important potential mechanisms and therapeutic approaches in renal IRI. PMID:26060833

  16. Cellular Basis of Anoxic-Ischemic Brain Injury

    PubMed Central

    Bronshvag, Michael M.

    1978-01-01

    Anoxic-ischemic cerebral disease is an important primary cause of morbidity and mortality, and also complicates a number of systemic diseases. Its clinical manifestations, such as hemiparesis and coma, represent cellular injury sustained by the complex, inhomogeneous brain. An understanding of the nature and pattern of anoxic-ischemic cerebral injury, and of the logical basis for avenues of therapy, is necessary to the management of patients with the various anoxic-ischemic disorders. PMID:685270

  17. Combined iron sucrose and protoporphyrin treatment protects against ischemic and toxin-mediated acute renal failure.

    PubMed

    Zager, Richard A; Johnson, Ali C M; Frostad, Kirsten B

    2016-07-01

    Tissue preconditioning, whereby various short-term stressors initiate organ resistance to subsequent injury, is well recognized. However, clinical preconditioning of the kidney for protection against acute kidney injury (AKI) has not been established. Here we tested whether a pro-oxidant agent, iron sucrose, combined with a protoporphyrin (Sn protoporphyrin), can induce preconditioning and protect against acute renal failure. Mice were pretreated with iron sucrose, protoporphyrin, cyanocobalamin, iron sucrose and protoporphyrin, or iron sucrose and cyanocobalamin. Eighteen hours later, ischemic, maleate, or glycerol models of AKI were induced, and its severity was assessed the following day (blood urea nitrogen, plasma creatinine concentrations; post-ischemic histology). Agent impact on cytoprotective gene expression (heme oxygenase 1, hepcidin, haptoglobin, hemopexin, α1-antitrypsin, α1-microglobulin, IL-10) was assessed as renal mRNA and protein levels. AKI-associated myocardial injury was gauged by plasma troponin I levels. Combination agent administration upregulated multiple cytoprotective genes and, unlike single agent administration, conferred marked protection against each tested model of acute renal failure. Heme oxygenase was shown to be a marked contributor to this cytoprotective effect. Preconditioning also blunted AKI-induced cardiac troponin release. Thus, iron sucrose and protoporphyrin administration can upregulate diverse cytoprotective genes and protect against acute renal failure. Associated cardiac protection implies potential relevance to both AKI and its associated adverse downstream effects. PMID:27165818

  18. Unilateral Renal Ischemia as a Model of Acute Kidney Injury and Renal Fibrosis in Cats.

    PubMed

    Schmiedt, C W; Brainard, B M; Hinson, W; Brown, S A; Brown, C A

    2016-01-01

    The objectives of this study were to define the acute and chronic effects of 1-hour unilateral in vivo renal ischemia on renal function and histology in cats. Twenty-one adult purpose-bred research cats were anesthetized, and 1 kidney underwent renal artery and vein occlusion for 1 hour. Serum creatinine and urea concentrations, urine protein:creatinine ratio, urine-specific gravity, glomerular filtration rate, hematocrit, platelet concentration and function, and white blood cell count were measured at baseline and variable time points after ischemia. Renal histopathology was evaluated on days 3, 6, 12, 21, 42, and 70 postischemia; changes in smooth muscle actin and interstitial collagen were examined. Following ischemia, whole animal glomerular filtration rate was significantly reduced (57% of baseline on day 6; P < .05). At the early time points, the ischemic kidneys exhibited severe acute epithelial necrosis accompanied by evidence of regeneration of tubules predominantly within the corticomedullary junction. At later periods, postischemic kidneys had evidence of tubular atrophy and interstitial inflammation with significantly more smooth muscle actin and interstitial collagen staining and interstitial fibrosis when compared with the contralateral control kidneys. This study characterizes the course of ischemic acute kidney injury in cats and demonstrates that ischemic acute kidney injury triggers chronic fibrosis, interstitial inflammation, and tubular atrophy in feline kidneys. These late changes are typical of those observed in cats with naturally occurring chronic kidney disease. PMID:26319781

  19. Leukocyte Recruitment and Ischemic Brain Injury

    PubMed Central

    Yilmaz, Gokhan

    2010-01-01

    Leukocytes are recruited into the cerebral microcirculation following an ischemic insult. The leukocyte–endothelial cell adhesion manifested within a few hours after ischemia (followed by reperfusion, I/R) largely reflects an infiltration of neutrophils, while other leukocyte populations appear to dominate the adhesive interactions with the vessel wall at 24 h of reperfusion. The influx of rolling and adherent leukocytes is accompanied by the recruitment of adherent platelets, which likely enhances the cytotoxic potential of the leukocytes to which they are attached. The recruitment of leukocytes and platelets in the postischemic brain is mediated by specific adhesion glycoproteins expressed by the activated blood cells and on cerebral microvascular endothelial cells. This process is also modulated by different signaling pathways (e.g., CD40/CD40L, Notch) and cytokines (e.g., RANTES) that are activated/released following I/R. Some of the known risk factors for cardiovascular disease, including hypercholesterolemia and obesity appear to exacerbate the leukocyte and platelet recruitment elicited by brain I/R. Although lymphocyte–endothelial cell and –platelet interactions in the postischemic cerebral microcirculation have not been evaluated to date, recent evidence in experimental animals implicate both CD4+ and CD8+ T-lymphocytes in the cerebral microvascular dysfunction, inflammation, and tissue injury associated with brain I/R. Evidence implicating regulatory T-cells as cerebroprotective modulators of the inflammatory and tissue injury responses to brain I/R support a continued focus on leukocytes as a target for therapeutic intervention in ischemic stroke. PMID:19579016

  20. Local and remote ischemic preconditioning protect against intestinal ischemic/reperfusion injury after supraceliac aortic clamping

    PubMed Central

    Erling, Nilon; de Souza Montero, Edna Frasson; Sannomiya, Paulina; Poli-de-Figueiredo (in memoriam), Luiz Francisco

    2013-01-01

    OBJECTIVES: This study tests the hypothesis that local or remote ischemic preconditioning may protect the intestinal mucosa against ischemia and reperfusion injuries resulting from temporary supraceliac aortic clamping. METHODS: Twenty-eight Wistar rats were divided into four groups: the sham surgery group, the supraceliac aortic occlusion group, the local ischemic preconditioning prior to supraceliac aortic occlusion group, and the remote ischemic preconditioning prior to supraceliac aortic occlusion group. Tissue samples from the small bowel were used for quantitative morphometric analysis of mucosal injury, and blood samples were collected for laboratory analyses. RESULTS: Supraceliac aortic occlusion decreased intestinal mucosal length by reducing villous height and elevated serum lactic dehydrogenase and lactate levels. Both local and remote ischemic preconditioning mitigated these histopathological and laboratory changes. CONCLUSIONS: Both local and remote ischemic preconditioning protect intestinal mucosa against ischemia and reperfusion injury following supraceliac aortic clamping. PMID:24473514

  1. Ischemic Postconditioning and Subanesthetic S(+)-Ketamine Infusion: Effects on Renal Function and Histology in Rats

    PubMed Central

    de Resende, Marco A. C.; Pantoja, Alberto V.; Barcellos, Bruno M.; Reis, Eduardo P.; Consolo, Thays D.; Módolo, Renata P.; Domingues, Maria A. C.; Assad, Alexandra R.; Cavalcanti, Ismar L.; Castiglia, Yara M. M.; Módolo, Norma S. P.

    2015-01-01

    Background. Ischemic postconditioning (IP) in renal Ischemia reperfusion injury (IRI) models improves renal function after IRI. Ketamine affords significant benefits against IRI-induced acute kidney injury (AKI). The present study investigated the effects of IP and IP associated with subanesthetic S(+)-ketamine in ischemia-reperfusion-induced AKI. Methods. Forty-one Wistar rats were randomized into four groups: CG (10), control; KG (10), S(+)-ketamine infusion; IPG (10), IP; and KIPG (11), S(+)-ketamine infusion + IP. All rats underwent right nephrectomy. IRI and IP were induced only in IPG and KIPG by left kidney arterial occlusion for 30 min followed by reperfusion for 24 h. Complete reperfusion was preceded by three cycles of 2 min of reocclusion followed by 2 min of reperfusion. Renal function was assessed by measuring serum neutrophil gelatinase-associated lipocalin (NGAL), creatinine, and blood urea nitrogen (BUN). Tubular damage was evaluated by renal histology. Results. Creatinine and BUN were significantly increased. Severe tubular injury was only observed in the groups with IRI (IPG and KIPG), whereas no injury was observed in CG or KG. No significant differences were detected between IPG and KIPG. Conclusions. No synergic effect of the use of subanesthetic S(+)-ketamine and IP on AKI was observed in this rat model. PMID:26413552

  2. OMA1 mediates OPA1 proteolysis and mitochondrial fragmentation in experimental models of ischemic kidney injury

    PubMed Central

    Xiao, Xiao; Hu, Yanzhong; Quirós, Pedro M.; Wei, Qingqing; López-Otín, Carlos

    2014-01-01

    Acute kidney injury (AKI) is associated with mitochondrial fragmentation, which contributes to mitochondrial damage and tubular cell apoptosis. Mitochondrial fragmentation involves the cleavage of both mitochondrial outer and inner membranes. Cleavage of the outer membrane results from Drp-1-mediated fission activation and Bak-promoted fusion arrest, but the molecular mechanism of inner membrane cleavage remains elusive. OMA1-mediated proteolysis of OPA1, a key inner membrane fusion protein, was recently suggested to account for inner membrane cleavage during cell stress. In this study, we determined the role of OMA1 in OPA1 proteolysis and mitochondrial fragmentation in experimental models of ischemic AKI. In ATP-depletion injury, knockdown of OMA1 suppressed OPA1 proteolysis, mitochondrial fragmentation, cytochrome c release, and consequent apoptosis in renal proximal tubular cells. In mice, OMA1 deficiency prevented ischemic AKI as indicated by better renal function, less tubular damage, and lower apoptosis. OPA1 proteolysis and mitochondrial injury during ischemic AKI were ameliorated in OMA1-deficient mice. Thus, OMA1-mediated OPA1 proteolysis plays an important role in the disruption of mitochondrial dynamics in ischemic AKI. PMID:24671334

  3. Kidney injury molecule-1 (KIM-1) mediates renal epithelial cell repair via ERK MAPK signaling pathway

    PubMed Central

    Zhang, Zhiwei; Cai, Cindy X

    2016-01-01

    The expression of kidney injury molecule-1 (KIM-1), a very promising sensitive and specific urinary biomarker for acute renal injury, is markedly upregulated in injured and regenerating renal proximal tubular epithelial cells following ischemic or toxic insults, suggesting a possible role for this molecule in renal repair process. In the present study we report that expression of KIM-1 facilitates renal tubular epithelial cell repair by promoting cell migration and proliferation. KIM-1 expression also enhances ERK MAPK activation, and the modulatory effect of KIM-1 on cellular repair process is likely mediated via ERK MAPK signaling pathway. PMID:27084535

  4. Kidney injury molecule-1 (KIM-1) mediates renal epithelial cell repair via ERK MAPK signaling pathway.

    PubMed

    Zhang, Zhiwei; Cai, Cindy X

    2016-05-01

    The expression of kidney injury molecule-1 (KIM-1), a very promising sensitive and specific urinary biomarker for acute renal injury, is markedly upregulated in injured and regenerating renal proximal tubular epithelial cells following ischemic or toxic insults, suggesting a possible role for this molecule in renal repair process. In the present study, we report that expression of KIM-1 facilitates renal tubular epithelial cell repair by promoting cell migration and proliferation. KIM-1 expression also enhances ERK MAPK activation, and the modulatory effect of KIM-1 on cellular repair process is likely mediated via ERK MAPK signaling pathway. PMID:27084535

  5. Acute vertebrobasilar ischemic stroke due to electric injury.

    PubMed

    Singh Jain, Rajendra; Kumar, Sunil; Suresh, Desai Tushar; Agarwal, Rakesh

    2015-07-01

    Electrical injuries are most commonly due to household accidents.Various factors determine the severity of electric injury, including type of current, amperage, voltage, tissue resistance, pathway of current,and duration of contact with the body. Various types of neurologic damage due to electrical injury have been described in literature. It may manifest as peripheral nerve injury, spinal cord damage, seizures, cerebellarataxia, hypoxic encephalopathy, and intracerebral hemorrhage. Acute ischemic stroke is an infrequent complication of electrical injury. Herein,we report a case of middle-aged man, who accidentally sustained high voltage electrical injury followed by acute vertebrobasilar ischemic stroke. Magnetic resonance imaging of the brain showed acute infarctin bilateral cerebellar and medial occipital regions. Computed tomographic angiogram of the brain and neck vessels was normal. Possibly,in our patient, the mechanism could be related to direct vascular injury due to electric current. PMID:25684743

  6. Inhibition of HDAC2 Protects the Retina From Ischemic Injury

    PubMed Central

    Fan, Jie; Alsarraf, Oday; Dahrouj, Mohammad; Platt, Kenneth A.; Chou, C. James; Rice, Dennis S.; Crosson, Craig E.

    2013-01-01

    Purpose. Protein acetylation is an essential mechanism in regulating transcriptional and inflammatory events. Studies have shown that nonselective histone deacetylase (HDAC) inhibitors can protect the retina from ischemic injury in rats. However, the role of specific HDAC isoforms in retinal degenerative processes remains obscure. The purpose of this study was to investigate the role of HDAC2 isoform in a mouse model of ischemic retinal injury. Methods. Localization of HDAC2 in mice retinas was evaluated by immunohistochemical analyses. To investigate whether selective reduction in HDAC2 activity can protect the retina from ischemic injury, Hdac2+/− mice were utilized. Electroretinographic (ERG) and morphometric analyses were used to assess retinal function and morphology. Results. Our results demonstrated that HDAC2 is primarily localized in nuclei in inner nuclear and retinal ganglion cell layers, and HDAC2 activity accounted for approximately 35% of the total activities of HDAC1, 2, 3, and 6 in the retina. In wild-type mice, ERG a- and b-waves from ischemic eyes were significantly reduced when compared to pre-ischemia baseline values. Morphometric examination of these eyes revealed significant degeneration of inner retinal layers. In Hdac2+/− mice, ERG a- and b-waves from ischemic eyes were significantly greater than those measured in ischemic eyes from wild-type mice. Morphologic measurements demonstrated that Hdac2+/− mice exhibit significantly less retinal degeneration than wild-type mice. Conclusions. This study demonstrated that suppressing HDAC2 expression can effectively reduce ischemic retinal injury. Our results support the idea that the development of selective HDAC2 inhibitors may provide an efficacious treatment for ischemic retinal injury. PMID:23696608

  7. Obesity Exacerbates Rat Cerebral Ischemic Injury through Enhancing Ischemic Adiponectin-Containing Neuronal Apoptosis.

    PubMed

    Wu, Ming-Hsiu; Chio, Chung-Ching; Tsai, Kuen-Jer; Chang, Ching-Ping; Lin, Nan-Kai; Huang, Chao-Ching; Lin, Mao-Tsun

    2016-08-01

    A diet consisting of high levels of saturated fat has been linked to a dramatic rise in obesity. Long-term exposure to high fat, "Western diet" (WD), is detrimental to ischemic brain injury. Adiponectin receptor 1 (ADR-1) activation is also shown to exacerbate ischemic neuronal death. However, it is not known whether increasing percentages of adiponectin (APN)-containing neurons attenuates ischemic neuronal apoptosis by modulating ADRS. To explore the role of APN and its ADRs in the development of acute cerebral injury, we subjected WD and control diet (CD) rats to 1 h of middle cerebral artery occlusion followed by 23 h of reperfusion. Compared with CD rats, WD rats exhibited higher levels of brain infarct, neurologic deficits, brain edema, and apoptosis of APN-containing neurons; upregulation of both ADR-1 and P38 mitogen-activated protein kinase (P38MAPK); and downregulation of ADR-2 in ischemic brain tissues including frontal cortex, striatum, and hippocampus. Increasing percentages of APN-containing neurons by baculovirus-mediated administration of APN, in addition to reducing apoptosis of APN-containing neurons in ischemic brain tissues, significantly attenuated brain infarct and edema, neurologic deficits, and altered expression of ADR-1, P38MAPK, and ADR-2 in both WD and CD group rats. These data suggest a negative correlation between percentages of APN-containing neurons and cerebral ischemic injury. Obesity could exacerbate rat cerebral ischemic injury by enhancing apoptosis of APN-containing neurons in ischemic brain tissues probably via modulating ADRs and P38MAPK. PMID:26126515

  8. Perioperative ischemic injury after coronary bypass graft surgery

    SciTech Connect

    Li, W.; Hanelin, L.G.; Riggins, R.C.; Agnew, R.C.; Annest, L.S.; Anderson, R.P.

    1985-07-01

    Two hundred twelve patients who underwent isolated coronary bypass graft surgery were prospectively evaluated for perioperative ischemic injury. All patients underwent preoperative and postoperative testing with technetium 99m pyrophosphate first-pass ventriculography combined with myocardial uptake scans, 12-lead electrocardiography, and serial creatinine phosphokinase MB determination. Fifteen percent of the patients had ischemic injury with at least two test results positive, but only 4 percent had positive results of all three tests. No single test proved adequate. Enzyme levels were highly sensitive and had value as a screening test. The electrocardiogram was specific but only moderately sensitive. The single best test was the radionuclide scan with good sensitivity and no false-positive results. All three tests are required to rigorously diagnose ischemic injury.

  9. Toll-Like Receptors and Ischemic Brain Injury

    PubMed Central

    Gesuete, Raffaella; Kohama, Steven G.; Stenzel-Poore, Mary

    2014-01-01

    Toll-like receptors (TLRs) are master regulators of innate immunity and play an integral role in the activation of the inflammatory response during infections. In addition, TLRs influence the body’s response to numerous forms of injury. Recent data have shown that TLRs play a modulating role in ischemic brain damage after stroke. Interestingly, their stimulation prior to ischemia induces a tolerant state that is neuroprotective. This phenomenon, referred to as TLR preconditioning, is the result of reprogramming of the TLR response to ischemic injury. This review addresses the role of TLRs in brain ischemia and the activation of endogenous neuroprotective pathways in the setting of preconditioning. We highlight the protective role of the interferon-related response and the potential site of action for TLR preconditioning involving the blood-brain-barrier. Pharmacological modulation of TLR activation to promote protection against stroke is a promising approach for the development of prophylactic and acute therapies targeting ischemic brain injury. PMID:24709682

  10. TLR9 Mediates Remote Liver Injury following Severe Renal Ischemia Reperfusion

    PubMed Central

    Bakker, Pieter J.; Scantlebery, Angelique M.; Butter, Loes M.; Claessen, Nike; Teske, Gwendoline J. D.; van der Poll, Tom; Florquin, Sandrine; Leemans, Jaklien C.

    2015-01-01

    Ischemia reperfusion injury is a common cause of acute kidney injury and is characterized by tubular damage. Mitochondrial DNA is released upon severe tissue injury and can act as a damage-associated molecular pattern via the innate immune receptor TLR9. Here, we investigated the role of TLR9 in the context of moderate or severe renal ischemia reperfusion injury using wild-type C57BL/6 mice or TLR9KO mice. Moderate renal ischemia induced renal dysfunction but did not decrease animal well-being and was not regulated by TLR9. In contrast, severe renal ischemia decreased animal well-being and survival in wild-type mice after respectively one or five days of reperfusion. TLR9 deficiency improved animal well-being and survival. TLR9 deficiency did not reduce renal inflammation or tubular necrosis. Rather, severe renal ischemia induced hepatic injury as seen by increased plasma ALAT and ASAT levels and focal hepatic necrosis which was prevented by TLR9 deficiency and correlated with reduced circulating mitochondrial DNA levels and plasma LDH. We conclude that TLR9 does not mediate renal dysfunction following either moderate or severe renal ischemia. In contrast, our data indicates that TLR9 is an important mediator of hepatic injury secondary to ischemic acute kidney injury. PMID:26361210

  11. The neuroprotective roles of BDNF in hypoxic ischemic brain injury.

    PubMed

    Chen, Ai; Xiong, Li-Jing; Tong, Yu; Mao, Meng

    2013-03-01

    Hypoxia-ischemia (H/I) brain injury results in various degrees of damage to the body, and the immature brain is particularly fragile to oxygen deprivation. Hypothermia and erythropoietin (EPO) have long been known to be neuroprotective in ischemic brain injury. Brain-derived neurotrophic factor (BDNF) has recently been recognized as a potent modulator capable of regulating a wide repertoire of neuronal functions. This review was based on studies concerning the involvement of BDNF in the protection of H/I brain injury following a search in PubMed between 1995 and December, 2011. We initially examined the background of BDNF, and then focused on its neuroprotective mechanisms against ischemic brain injury, including its involvement in promoting neural regeneration/cognition/memory rehabilitation, angiogenesis within ischemic penumbra and the inhibition of the inflammatory process, neurotoxicity, epilepsy and apoptosis. We also provided a literature overview of experimental studies, discussing the safety and the potential clinical application of BDNF as a neuroprotective agent in the ischemic brain injury. PMID:24648914

  12. Should blunt segmental vascular renal injuries be considered an AAST grade 4 renal injury?

    PubMed Central

    Malaeb, Bahaa; Figler, Brad; Wessells, Hunter; Voelzke, Bryan B.

    2013-01-01

    Background Renal segmental vascular injury (SVI) following blunt abdominal trauma is not part of the original AAST renal injury grading system. Recent recommendations support classifying SVI as an AAST grade 4 injury. Our primary aim was to compare outcomes following blunt renal SVI and blunt renal collecting system lacerations (CSL). We hypothesize that renal SVI fare well with conservative management alone and should be relegated a less severe renal AAST grade. Methods We retrospectively identified patients with SVI and G4 CSL admitted to a Level 1 trauma center between 2003–2010. Penetrating trauma was excluded. Need for surgical intervention, length of stay, kidney salvage (>25% renal preservation on renography 6–12 weeks after injury), and delayed complication rates were compared between the SVI and CSL injuries. Statistical analysis utilized chi squared, Fisher exact, and t-test. Results 56 patients with SVI and 88 patients with G4 CSL sustained blunt trauma. Age, injury severity score, and length of stay were similar for the two groups. Five patients in each group died of concomitant, non-renal injuries. In the G4 CSL group, 15 patients underwent major interventions and 32 patients underwent minor interventions. Only one patient in the SVI group underwent a major intervention. The renal salvage rate was 85.7% following SVI versus 62.5% following CSL (p=0.107). Conclusions Overall surgical interventions are significantly lower among the SVI cohort than G4 CSL cohort. Further analysis using a larger cohort of patients is recommended before revising the current renal grading system. Adding SVI as a grade 4 injury could potentially increase the heterogeneity of grade 4 injuries and decrease the ability of the AAST renal injury grading system to predict outcomes, such as nephrectomy rate. Level of Evidence IV (retrospective, cohort study) PMID:24458054

  13. Mild ischemic Injury Leads to Long-Term Alterations in the Kidney: Amelioration by Spironolactone Administration

    PubMed Central

    Barrera-Chimal, Jonatan; Pérez-Villalva, Rosalba; Ortega, Juan Antonio; Sánchez, Andrea; Rodríguez-Romo, Roxana; Durand, Marta; Jaisser, Frederic; Bobadilla, Norma A.

    2015-01-01

    Administration of the mineralocorticoid receptor antagonist spironolactone prevents the development of chronic kidney disease (CKD) after a severe ischemic injury. However, whether brief periods of ischemia lead to CKD and whether spironolactone administration after ischemia may be a useful therapeutic strategy to prevent the gradual deterioration of structure and function remains unexplored. Nineteen male Wistar rats were divided into four groups: rats that underwent renal bilateral ischemia for 10, 20, or 45 min were compared with sham operated rats. Additionally, thirteen male Wistar rats that underwent renal bilateral ischemia for 20 min were divided into an untreated ischemic group (I) and two groups receiving spironolactone, 20 mg/kg by gavage, at either 0 (Sp0) or 1.5-h after ischemia (Sp1.5). The rats were followed up and studied after 9 months. Mild (20 min) and severe (45 min) ischemia induced a progressive increase in proteinuria at varying magnitudes, whereas minor ischemia (10 min) did not modify proteinuria. CKD induced by moderate ischemia was characterized by renal hypertrophy and tubulointerstitial fibrosis. These effects were associated with activation of the transforming growth factor β (TGFβ) signaling pathway and up-regulation of endothelin receptor A (ETA) and alpha smooth muscle actin (αSMA). Spironolactone treatment immediately or 1.5-h after the ischemic insult prevented the onset of these disorders. Our results show that moderate ischemic insult leads to long-term structural and molecular changes that may compromise renal function in later stages. Additionally, we demonstrate that spironolactone administration after mild ischemia prevents this detrimental effect. PMID:26157344

  14. Mild ischemic injury leads to long-term alterations in the kidney: amelioration by spironolactone administration.

    PubMed

    Barrera-Chimal, Jonatan; Pérez-Villalva, Rosalba; Ortega, Juan Antonio; Sánchez, Andrea; Rodríguez-Romo, Roxana; Durand, Marta; Jaisser, Frederic; Bobadilla, Norma A

    2015-01-01

    Administration of the mineralocorticoid receptor antagonist spironolactone prevents the development of chronic kidney disease (CKD) after a severe ischemic injury. However, whether brief periods of ischemia lead to CKD and whether spironolactone administration after ischemia may be a useful therapeutic strategy to prevent the gradual deterioration of structure and function remains unexplored. Nineteen male Wistar rats were divided into four groups: rats that underwent renal bilateral ischemia for 10, 20, or 45 min were compared with sham operated rats. Additionally, thirteen male Wistar rats that underwent renal bilateral ischemia for 20 min were divided into an untreated ischemic group (I) and two groups receiving spironolactone, 20 mg/kg by gavage, at either 0 (Sp0) or 1.5-h after ischemia (Sp1.5). The rats were followed up and studied after 9 months. Mild (20 min) and severe (45 min) ischemia induced a progressive increase in proteinuria at varying magnitudes, whereas minor ischemia (10 min) did not modify proteinuria. CKD induced by moderate ischemia was characterized by renal hypertrophy and tubulointerstitial fibrosis. These effects were associated with activation of the transforming growth factor β (TGFβ) signaling pathway and up-regulation of endothelin receptor A (ETA) and alpha smooth muscle actin (αSMA). Spironolactone treatment immediately or 1.5-h after the ischemic insult prevented the onset of these disorders. Our results show that moderate ischemic insult leads to long-term structural and molecular changes that may compromise renal function in later stages. Additionally, we demonstrate that spironolactone administration after mild ischemia prevents this detrimental effect. PMID:26157344

  15. Suppression of Acid Sphingomyelinase Protects the Retina from Ischemic Injury

    PubMed Central

    Fan, Jie; Wu, Bill X.; Crosson, Craig E.

    2016-01-01

    Purpose Acid sphingomyelinase (ASMase) catalyzes the hydrolysis of sphingomyelin to ceramide and mediates multiple responses involved in inflammatory and apoptotic signaling. However, the role ASMase plays in ischemic retinal injury has not been investigated. The purpose of this study was to investigate how reduced ASMase expression impacts retinal ischemic injury. Methods Changes in ceramide levels and ASMase activity were determined by high performance liquid chromatography-tandem mass spectrometry analysis and ASMase activity. Retinal function and morphology were assessed by electroretinography (ERG) and morphometric analyses. Levels of TNF-α were determined by ELISA. Activation of p38 MAP kinase was assessed by Western blot analysis. Results In wild-type mice, ischemia produced a significant increase in retinal ASMase activity and ceramide levels. These increases were associated with functional deficits as measured by ERG analysis and significant structural degeneration in most retinal layers. In ASMase+/− mice, retinal ischemia did not significantly alter ASMase activity, and the rise in ceramide levels were significantly reduced compared to levels in retinas from wild-type mice. In ASMase+/− mice, functional and morphometric analyses of ischemic eyes revealed significantly less retinal degeneration than in injured retinas from wild-type mice. The ischemia-induced increase in retinal TNF-α levels was suppressed by the administration of the ASMase inhibitor desipramine, or by reducing ASMase expression. Conclusions Our results demonstrate that reducing ASMase expression provides partial protection from ischemic injury. Hence, the production of ceramide and subsequent mediators plays a role in the development of ischemic retinal injury. Modulating ASMase may present new opportunities for adjunctive therapies when treating retinal ischemic disorders. PMID:27571014

  16. A Novel Therapy to Attenuate Acute Kidney Injury and Ischemic Allograft Damage after Allogenic Kidney Transplantation in Mice

    PubMed Central

    Gueler, Faikah; Shushakova, Nelli; Mengel, Michael; Hueper, Katja; Chen, Rongjun; Liu, Xiaokun; Park, Joon-Keun; Haller, Hermann

    2015-01-01

    Ischemia followed by reperfusion contributes to the initial damage to allografts after kidney transplantation (ktx). In this study we tested the hypothesis that a tetrapeptide EA-230 (AQGV), might improve survival and attenuate loss of kidney function in a mouse model of renal ischemia/reperfusion injury (IRI) and ischemia-induced delayed graft function after allogenic kidney transplantation. IRI was induced in male C57Bl/6N mice by transient bilateral renal pedicle clamping for 35 min. Treatment with EA-230 (20–50mg/kg twice daily i.p. for four consecutive days) was initiated 24 hours after IRI when acute kidney injury (AKI) was already established. The treatment resulted in markedly improved survival in a dose dependent manner. Acute tubular injury two days after IRI was diminished and tubular epithelial cell proliferation was significantly enhanced by EA-230 treatment. Furthermore, CTGF up-regulation, a marker of post-ischemic fibrosis, at four weeks after IRI was significantly less in EA-230 treated renal tissue. To learn more about these effects, we measured renal blood flow (RBF) and glomerular filtration rate (GFR) at 28 hours after IRI. EA-230 improved both GFR and RBF significantly. Next, EA-230 treatment was tested in a model of ischemia-induced delayed graft function after allogenic kidney transplantation. The recipients were treated with EA-230 (50 mg/kg) twice daily i.p. which improved renal function and allograft survival by attenuating ischemic allograft damage. In conclusion, EA-230 is a novel and promising therapeutic agent for treating acute kidney injury and preventing IRI-induced post-transplant ischemic allograft injury. Its beneficial effect is associated with improved renal perfusion after IRI and enhanced regeneration of tubular epithelial cells. PMID:25617900

  17. Investigation of Reperfusion Injury and Ischemic Preconditioning in Microsurgry

    PubMed Central

    Wang, Wei Zhong

    2008-01-01

    Ischemia/reperfusion (I/R) is inevitable in many vascular and musculoskeletal traumas, diseases, free tissue transfers, and during time-consuming reconstructive surgeries in the extremities. Salvage of a prolonged ischemic extremity or flap still remains a challenge for the microvascular surgeon. One of the common complications after microsurgery is I/R-induced tissue death or I/R injury. Twenty years after the discovery, ischemic preconditioning (IPC) has emerged as a powerful method for attenuating I/R injury in a variety of organs or tissues. However, its therapeutic expectations still need to be fulfilled. In this article, the author reviews some important experimental evidences of I/R injury as well as preconditioning-induced protection in the fields relevant to microsurgery. PMID:18946882

  18. Astaxanthin reduces ischemic brain injury in adult rats.

    PubMed

    Shen, Hui; Kuo, Chi-Chung; Chou, Jenny; Delvolve, Alice; Jackson, Shelley N; Post, Jeremy; Woods, Amina S; Hoffer, Barry J; Wang, Yun; Harvey, Brandon K

    2009-06-01

    Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events. PMID:19218497

  19. A Double Blind Randomized Clinical Trial of Remote Ischemic Conditioning in Live Donor Renal Transplantation

    PubMed Central

    Nicholson, Michael L.; Pattenden, Clare J.; Barlow, Adam D.; Hunter, James P.; Lee, Gwyn; Hosgood, Sarah A.

    2015-01-01

    Abstract Ischemic conditioning involves the delivery of short cycles of reversible ischemic injury in order to induce protection against subsequent more prolonged ischemia. This randomized controlled trial was designed to determine the safety and efficacy of remote ischemic conditioning (RC) in live donor kidney transplantation. This prospective randomized clinical trial, 80 patients undergoing live donor kidney transplantation were randomly assigned in a 1:1 ratio to either RC or to a control group. RC consisted of cycles of lower limb ischemia induced by an arterial tourniquet cuff placed around the patient's thigh. In the RC treatment group, the cuff was inflated to 200 mm Hg or systolic pressure +25 mm Hg for 4 cycles of 5 min ischemia followed by 5 min reperfusion. In the control group, the blood pressure cuff was inflated to 25 mm Hg. Patients and medical staff were blinded to treatment allocation. The primary end-point was renal function measured by estimated glomerular filtration rate (eGFR) at 1 and 3 months posttransplant. Donor and recipient demographics were similar in both groups (P < 0.05). There were no significant differences in eGFR at 1 month (control 52 ± 14 vs RC 54 ± 17 mL/min; P = 0.686) or 3 months (control 50 ± 14 vs RC 49 ± 18 mL/min; P = 0.678) between the control and RC treatment groups. The RC technique did not cause any serious adverse effects. RC, using the protocol described here, did not improve renal function after live donor kidney transplantation. PMID:26252316

  20. Astaxanthin reduces ischemic brain injury in adult rats

    PubMed Central

    Shen, Hui; Kuo, Chi-Chung; Chou, Jenny; Delvolve, Alice; Jackson, Shelley N.; Post, Jeremy; Woods, Amina S.; Hoffer, Barry J.; Wang, Yun; Harvey, Brandon K.

    2009-01-01

    Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events.—Shen, H., Kuo, C.-C., Chou, J., Delvolve, A., Jackson, S. N., Post, J., Woods, A. S., Hoffer, B. J., Wang, Y., Harvey, B. K. Astaxanthin reduces ischemic brain injury in adult rats. PMID:19218497

  1. Role of fibrinogen in acute ischemic kidney injury.

    PubMed

    Sörensen-Zender, I; Rong, S; Susnik, N; Lange, J; Gueler, F; Degen, J L; Melk, A; Haller, H; Schmitt, R

    2013-09-01

    Renal ischemia-reperfusion (I/R) is associated with activation of the coagulation system and accumulation of blood clotting factors in the kidney. The aim of the present study was to examine the functional impact of fibrinogen on renal inflammation, damage, and repair in the context of I/R injury. In this study, we found that I/R was associated with a significant increase in the renal deposition of circulating fibrinogen. In parallel, I/R stress induced the de novo expression of fibrinogen in tubular epithelial cells, as reflected by RT-PCR, immunofluorescence, and in situ hybridization. In vitro, fibrinogen expression was induced by oncostatin M and hyper-IL-6 in primary tubular epithelial cells, and fibrinogen-containing medium had an inhibitory effect on tubular epithelial cell adhesion and migration. Fibrinogen(+/-) mice showed similar survival as wild-type mice but better preservation in early postischemic renal function. In fibrinogen(-/-) mice, renal function and survival were significantly worse than in fibrinogen(+/-) mice. Renal transplant experiments revealed reduced expression of tubular damage markers and attenuated proinflammatory cytokine expression but increased inflammatory cell infiltrates and transforming growth factor-β expression in fibrinogen(-/-) isografts. These data point to heterogeneous effects of fibrinogen in renal I/R injury. While a complete lack of fibrinogen may be detrimental, partial reduction of fibrinogen in heterozygous mice can improve renal function and overall outcome. PMID:23804451

  2. Protein methionine oxidation augments reperfusion injury in acute ischemic stroke

    PubMed Central

    Gu, Sean X.; Blokhin, Ilya O.; Wilson, Katina M.; Dhanesha, Nirav; Doddapattar, Prakash; Grumbach, Isabella M.; Chauhan, Anil K.; Lentz, Steven R.

    2016-01-01

    Reperfusion injury can exacerbate tissue damage in ischemic stroke, but little is known about the mechanisms linking ROS to stroke severity. Here, we tested the hypothesis that protein methionine oxidation potentiates NF-κB activation and contributes to cerebral ischemia/reperfusion injury. We found that overexpression of methionine sulfoxide reductase A (MsrA), an antioxidant enzyme that reverses protein methionine oxidation, attenuated ROS-augmented NF-κB activation in endothelial cells, in part, by protecting against the oxidation of methionine residues in the regulatory domain of calcium/calmodulin-dependent protein kinase II (CaMKII). In a murine model, MsrA deficiency resulted in increased NF-κB activation and neutrophil infiltration, larger infarct volumes, and more severe neurological impairment after transient cerebral ischemia/reperfusion injury. This phenotype was prevented by inhibition of NF-κB or CaMKII. MsrA-deficient mice also exhibited enhanced leukocyte rolling and upregulation of E-selectin, an endothelial NF-κB–dependent adhesion molecule known to contribute to neurovascular inflammation in ischemic stroke. Finally, bone marrow transplantation experiments demonstrated that the neuroprotective effect was mediated by MsrA expressed in nonhematopoietic cells. These findings suggest that protein methionine oxidation in nonmyeloid cells is a key mechanism of postischemic oxidative injury mediated by NF-κB activation, leading to neutrophil recruitment and neurovascular inflammation in acute ischemic stroke. PMID:27294204

  3. [Renal injury in Takayasu's arteritis].

    PubMed

    Boubaker, Karima; Kaaroud, Hayet; Goucha, Rim; Kheder, Adel

    2014-11-01

    Renal involvement in Takayasu's arteritis is frequent and worsens the progression of the disease. This is primarily a renal artery stenosis causing renovascular hypertension. The glomerular disease is exceptional. This study was undertaken to determine the clinical, radiological, biological features and therapeutic response in patients with kidney disease associated with Takayasu arteritis. A retrospective chart review was conducted on 11 patients (five men and six females), with a mean age of 31.1 years (19-40 years). The discovery of kidney disease preceded the diagnosis of Takayasu's arteritis in eight cases. Ten patients developed hypertension. Laboratory finding showed proteinuria in five cases of which one case was due to nephrotic syndrome. Renal failure was found in six cases including four cases in stage of terminal chronic renal failure. Impairment of the renal artery was present in nine patients, proximal in seven cases and distal in two cases, bilateral in five cases and unilateral in four cases. Narrowing renal artery was found in seven cases. The renal biopsy revealed membranoproliferative glomerulonephritis in one case and nephrosclerosis in another case. Eleven patients were followed for an average period of 155 months (3-335 months). Remission of nephrotic syndrome was concomitant with the remission of the disease. Seven patients developed outbreaks of Takayasu's arteritis of which six were in care. Relapse of nephrotic syndrome was concomitant with the outbreak of the disease followed by spontaneous remission of both diseases. Improved pressure was obtained in 5 cases and worsening renal function in seven cases. Death was observed in two cases. PMID:25440941

  4. Peptidyl arginine deiminase-4-deficient mice are protected against kidney and liver injury after renal ischemia and reperfusion.

    PubMed

    Rabadi, May; Kim, Mihwa; D'Agati, Vivette; Lee, H Thomas

    2016-08-01

    We previously demonstrated that renal peptidyl arginine deiminase-4 (PAD4) is induced after renal ischemia and reperfusion (I/R) injury and exacerbates acute kidney injury (AKI) by increasing the renal tubular inflammatory response. Here, we tested whether genetic ablation of PAD4 attenuates renal injury and inflammation after I/R in mice. After renal I/R, PAD4 wild-type mice develop severe AKI with large increases in plasma creatinine, neutrophil infiltration, as well as significant renal tubular necrosis, apoptosis, and proinflammatory cytokine generation. In contrast, PAD4-deficient mice are protected against ischemic AKI with reduced real tubular neutrophil infiltration, renal tubular necrosis, and apoptosis. In addition, hepatic injury and inflammation observed in PAD4 wild-type mice after renal I/R are significantly attenuated in PAD4-deficient mice. We also show that increased renal tubular PAD4 expression after renal I/R is associated with translocation of PAD4 from the nucleus to the cytosol. Consistent with PAD4 cytosolic translocation, we show increased renal tubular cytosolic peptidyl-citrullination after ischemic AKI. Mechanistically, recombinant PAD4 treatment increased nuclear translocation of NF-κB in cultured human as well as murine proximal tubule cells that is inhibited by a PAD4 inhibitor (2-chloroamidine). Taken together, our studies further support the hypothesis that renal tubular PAD4 plays a critical role in renal I/R injury by increasing the renal tubular inflammatory response and neutrophil infiltration after renal I/R perhaps by interacting with the proinflammatory transcription factor NF-κB in the cytosol and promoting its nuclear translocation. PMID:27335376

  5. Nitrite-mediated renal vasodilatation is increased during ischemic conditions via cGMP-independent signaling.

    PubMed

    Liu, Ming; Zollbrecht, Christa; Peleli, Maria; Lundberg, Jon O; Weitzberg, Eddie; Carlström, Mattias

    2015-07-01

    The kidney is vulnerable to hypoxia, and substantial efforts have been made to ameliorate renal ischemic injury secondary to pathological conditions. Stimulation of the nitrate-nitrite-nitric oxide pathway is associated with renal and cardiovascular protection in disease models, but less is known about the vascular effects during renal ischemia. This study was aimed at investigating the vascular effects of nitrite in the kidney during normoxic and ischemic conditions. Using a multiwire myograph system, we assessed nitrite-mediated relaxation (10(-9)-10(-4)mol/L) in isolated and preconstricted renal interlobar arteries from C57BL/6 mice under normal conditions (pO2 13kPa; pH 7.4) and with low oxygen tension and low pH to mimic ischemia (pO2 3kPa; pH 6.6). Xanthine oxidoreductase expression was analyzed by quantitative PCR, and production of reactive nitrogen species was measured by DAF-FM DA fluorescence. During normoxia significant vasodilatation (15±3%) was observed only at the highest concentration of nitrite, which was dependent on NO-sGC-cGMP signaling. The vasodilatory responses to nitrite were greatly sensitized and enhanced during hypoxia with low pH, demonstrating significant dilatation (11±1%) already in the physiological range (10(-8)mol/L), with a maximum response of 27±2% at 10(-4) mol/L. In contrast to normoxia, and to that observed with a classical NO donor (DEA NONOate), this sensitization was independent of sGC-cGMP signaling. Moreover, inhibition of various enzymatic systems reported to reduce nitrite in other vascular beds, i.e., aldehyde oxidase (raloxifene), aldehyde dehydrogenase (cyanamide), and NO synthase (L-NAME), had no effect on the nitrite response. However, inhibition of xanthine oxidoreductase (XOR; febuxostat or allopurinol) abolished the sensitized response to nitrite during hypoxia and acidosis. In conclusion, in contrast to normoxia, nitrite exerted potent vasorelaxation during ischemic conditions already at physiological

  6. Bone Fracture Pre-Ischemic Stroke Exacerbates Ischemic Cerebral Injury in Mice

    PubMed Central

    Zou, Dingquan; Zhan, Lei; Li, Zhengxi; Zhu, Wan; Su, Hua

    2016-01-01

    Ischemic stroke is a devastating complication of bone fracture. Bone fracture shortly after stroke enhances stroke injury by augmenting inflammation. We hypothesize that bone fracture shortly before ischemic stroke also exacerbates ischemic cerebral injury. Tibia fracture was performed 6 or 24 hours before permanent middle cerebral artery occlusion (pMCAO) on C57BL/6J mice or Ccr2RFP/+Cx3cr1GFP/+ mice that have the RFP gene knocked into one allele of Ccr2 gene and GFP gene knocked into one allele of Cx3cr1 gene. Behavior was tested 3 days after pMCAO. Infarct volume, the number of CD68+ cells, apoptotic neurons, bone marrow-derived macrophages (RFP+), and microgila (GFP+) in the peri-infarct region were quantified. Compared to mice subjected to pMCAO only, bone fracture 6 or 24 hours before pMCAO increased behavioral deficits, the infarct volume, and the number of CD68+ cells and apoptotic neurons in the peri-infarct area. Both bone marrow-derived macrophages (CCR2+) and microglia (CX3CR1+) increased in the peri-infarct regions of mice subjected to bone fracture before pMCAO compared to stroke-only mice. The mice subjected to bone fracture 6 hours before pMCAO had more severe injury than mice that had bone fracture 24 hours before pMCAO. Our data showed that bone fracture shortly before stroke also increases neuroinflammation and exacerbates ischemic cerebral injury. Our findings suggest that inhibition of neuroinflammation or management of stroke risk factors before major bone surgery would be beneficial for patients who are likely to suffer from stroke. PMID:27089041

  7. Renal artery injury during robot-assisted renal surgery.

    PubMed

    Lee, Jae Won; Yoon, Young Eun; Kim, Dae Keun; Park, Sung Yul; Moon, Hong Sang; Lee, Tchun Yong

    2010-07-01

    Laparoscopic partial nephrectomy (LPN) is becoming the standard of care for incidentally diagnosed, small renal tumors. With its seven degrees of freedom and three-dimensional vision, the DaVinci robotic surgical system has been used to assist in LPNs. The main disadvantage of robot-assisted surgery, however, is the lack of tactile feedback. We present a case of renal artery injury during robot-assisted renal surgery. Robot-assisted partial nephrectomy (RPN) was planned for 47-year-old man with a 3.5-cm right renal mass. After standard bowel mobilization, renal hilar dissection was performed. In the attempt to complete the dissection posteriorly, however, there was sudden profuse bleeding. The intraperitoneal pressure immediately increased to 20 mm Hg, and an additional suction device was inserted through the 5-mm liver retractor port. On inspection, there was an injury at the takeoff of the posterior segmental artery. A decision was made to convert to robot-assisted laparoscopic radical nephrectomy. The main renal artery and renal vein were controlled with Hem-o-Lok clips. The estimated blood loss was 2,000 mL. Four units of packed red blood cells were transfused intraoperatively. The post-transfusion hemoglobin level was 12.6 g/dL. There were no other perioperative complications. The surgeon should keep in mind that the robotic arms are very powerful and can easily injure major vessels because of lack of tactile feedback. A competent and experienced tableside surgeon is very important in robot-assisted surgery because the unsterile console surgeon cannot immediately react to intraoperative complications. PMID:20590468

  8. Antisense oligonucleotide for tissue factor inhibits hepatic ischemic reperfusion injury.

    PubMed

    Nakamura, Kenji; Kadotani, Yayoi; Ushigome, Hidetaka; Akioka, Kiyokazu; Okamoto, Masahiko; Ohmori, Yoshihiro; Yaoi, Takeshi; Fushiki, Shinji; Yoshimura, Rikio; Yoshimura, Norio

    2002-09-27

    Tissue factor (TF) is an initiation factor for blood coagulation and its expression is induced on endothelial cells during inflammatory or immune responses. We designed an antisense oligodeoxynucleotide (AS-1/TF) for rat TF and studied its effect on hepatic ischemic reperfusion injury. AS-1/TF was delivered intravenously to Lewis rats. After 10 h, hepatic artery and portal vein were partially clamped. Livers were reperfused after 180 min and harvested. TF expression was studied using immunohistochemical staining. One of 10 rats survived in a 5-day survival rate and TF was strongly stained on endothelial cells in non-treatment group. However, by treatment with AS-1/TF, six of seven survived and TF staining was significantly reduced. Furthermore, we observed that fluorescein-labeled AS-1/TF was absorbed into endothelial cells. These results suggest that AS-1/TF can strongly suppress the expression of TF and thereby inhibit ischemic reperfusion injury to the rat liver. PMID:12270110

  9. Ischemic postconditioning protects against ischemic brain injury by up-regulation of acid-sensing ion channel 2a

    PubMed Central

    Duanmu, Wang-sheng; Cao, Liu; Chen, Jing-yu; Ge, Hong-fei; Hu, Rong; Feng, Hua

    2016-01-01

    Ischemic postconditioning renders brain tissue tolerant to brain ischemia, thereby alleviating ischemic brain injury. However, the exact mechanism of action is still unclear. In this study, a rat model of global brain ischemia was subjected to ischemic postconditioning treatment using the vessel occlusion method. After 2 hours of ischemia, the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds. This procedure was repeated six times. Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia, and up-regulate acid-sensing ion channel 2a expression at the mRNA and protein level. These findings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippocampus after global brain ischemia, which promotes neuronal tolerance to ischemic brain injury. PMID:27212927

  10. Cytokines induce small intestine and liver injury after renal ischemia or nephrectomy

    PubMed Central

    Park, Sang Won; Chen, Sean W.C.; Kim, Mihwa; Brown, Kevin M.; Kolls, Jay K.; D’Agati, Vivette D.; Lee, H. Thomas

    2010-01-01

    Patients with acute kidney injury (AKI) frequently suffer from extra-renal complications including hepatic dysfunction and systemic inflammation. We aimed to determine the mechanisms of AKI induced hepatic dysfunction and systemic inflammation. Mice subjected to AKI [renal ischemia reperfusion (IR) or nephrectomy] rapidly developed acute hepatic dysfunction and suffered significantly worse hepatic IR injury. After AKI, rapid peri-portal hepatocyte necrosis, vacuolization, neutrophil infiltration and pro-inflammatory mRNA upregulation were observed suggesting an intestinal source of hepatic injury. Small intestine histology after AKI demonstrated profound villous lacteal capillary endothelial apoptosis, disruption of vascular permeability and epithelial necrosis. After ischemic or non-ischemic AKI, plasma TNF-α, IL-17A and IL-6 increased significantly. Small intestine appears to be the source of IL-17A as IL-17A levels were higher in the portal circulation and small intestine compared to the levels measured from the systemic circulation and liver. Wild type mice treated with neutralizing antibodies against TNF-α, IL-17A or IL-6 or mice deficient in TNF-α, IL-17A, IL-17A receptor or IL-6 were protected against hepatic and small intestine injury due to ischemic or non-ischemic AKI. For the first time, we implicate the increased release of IL-17A from small intestine together with induction of TNF-α and IL-6 as a cause of small intestine and liver injury after ischemic or non-ischemic AKI. Modulation of the inflammatory response and cytokine release in the small intestine after AKI may have important therapeutic implications in reducing complications arising from AKI. PMID:20697374

  11. Optical spectroscopy for the detection of ischemic tissue injury

    DOEpatents

    Demos, Stavros; Fitzgerald, Jason; Troppmann, Christoph; Michalopoulou, Andromachi

    2009-09-08

    An optical method and apparatus is utilized to quantify ischemic tissue and/or organ injury. Such a method and apparatus is non-invasive, non-traumatic, portable, and can make measurements in a matter of seconds. Moreover, such a method and apparatus can be realized through optical fiber probes, making it possible to take measurements of target organs deep within a patient's body. Such a technology provides a means of detecting and quantifying tissue injury in its early stages, before it is clinically apparent and before irreversible damage has occurred.

  12. Oxidant Mechanisms in Renal Injury and Disease

    PubMed Central

    Ratliff, Brian B.; Abdulmahdi, Wasan; Pawar, Rahul

    2016-01-01

    Abstract Significance: A common link between all forms of acute and chronic kidney injuries, regardless of species, is enhanced generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) during injury/disease progression. While low levels of ROS and RNS are required for prosurvival signaling, cell proliferation and growth, and vasoreactivity regulation, an imbalance of ROS and RNS generation and elimination leads to inflammation, cell death, tissue damage, and disease/injury progression. Recent Advances: Many aspects of renal oxidative stress still require investigation, including clarification of the mechanisms which prompt ROS/RNS generation and subsequent renal damage. However, we currently have a basic understanding of the major features of oxidative stress pathology and its link to kidney injury/disease, which this review summarizes. Critical Issues: The review summarizes the critical sources of oxidative stress in the kidney during injury/disease, including generation of ROS and RNS from mitochondria, NADPH oxidase, and inducible nitric oxide synthase. The review next summarizes the renal antioxidant systems that protect against oxidative stress, including superoxide dismutase and catalase, the glutathione and thioredoxin systems, and others. Next, we describe how oxidative stress affects kidney function and promotes damage in every nephron segment, including the renal vessels, glomeruli, and tubules. Future Directions: Despite the limited success associated with the application of antioxidants for treatment of kidney injury/disease thus far, preventing the generation and accumulation of ROS and RNS provides an ideal target for potential therapeutic treatments. The review discusses the shortcomings of antioxidant treatments previously used and the potential promise of new ones. Antioxid. Redox Signal. 25, 119–146. PMID:26906267

  13. Ischemic retinopathy and neovascular proliferation secondary to severe head injury.

    PubMed

    Coban-Karatas, Muge; Altan-Yaycioglu, Rana

    2014-01-01

    We report a case with severe head trauma and perforating globe injury in one eye and ischemic retinopathy and neovascular proliferation in the other eye. A 37-year-old male was brought to the emergency department after a motor vehicle accident with severe maxillofacial trauma. Ophthalmic examination revealed hematoma of the left eyelids as well as traumatic rupture and disorganization of the left globe. On the right eye, anterior segment and fundoscopic examination were normal. Primary globe repair was performed. At postoperative one-month visit, the right eye revealed no pathology of the optic disc and macula but severe neovascularization in the temporal peripheral retina. The patient was diagnosed as ischemic retinopathy and neovascular proliferation due to head trauma. PMID:25143848

  14. Remote ischemic preconditioning as treatment for non-ischemic gastrointestinal disorders: beyond ischemia-reperfusion injury.

    PubMed

    Camara-Lemarroy, Carlos Rodrigo

    2014-04-01

    Common gastrointestinal diseases such as radiation enteritis (RE), acute pancreatitis, inflammatory bowel diseases (IBD) and drug-induced hepatotoxicity share pathophysiological mechanisms at the molecular level, mostly involving the activation of many pathways of the immune response, ultimately leading to tissue injury. Increased oxidative stress, inflammatory cytokine release, inflammatory cell infiltration and activation and the up-regulation of inflammatory transcription factors participate in the pathophysiology of these complex entities. Treatment varies in each specific disease, but at least in the cases of RE and IBD immunosuppressors are effective. However, full therapeutic responses are not always achieved. The pathophysiology of ischemia-reperfusion (IR) injury shares many of these mechanisms. Brief and repetitive periods of ischemia in an organ or limb have been shown to protect against subsequent major IR injury in distant organs, a phenomenon called remote ischemic preconditioning (RIP). This procedure has been shown to protect the gut, pancreas and liver by modulating many of the same inflammatory mechanisms. Since RIP is safe and tolerable, and has shown to be effective in some recent clinical trials, I suggest that RIP could be used as a physiologically relevant adjunct treatment for non-ischemic gastrointestinal inflammatory conditions. PMID:24707140

  15. Delayed Postconditioning Protects against Focal Ischemic Brain Injury in Rats

    PubMed Central

    Ren, Chuancheng; Gao, Xuwen; Niu, Gang; Yan, Zhimin; Chen, Xiaoyuan; Zhao, Heng

    2008-01-01

    Background We and others have reported that rapid ischemic postconditioning, interrupting early reperfusion after stroke, reduces infarction in rats. However, its extremely short therapeutic time windows, from a few seconds to minutes after reperfusion, may hinder its clinical translation. Thus, in this study we explored if delayed postconditioning, which is conducted a few hours after reperfusion, offers protection against stroke. Methods and Results Focal ischemia was generated by 30 min occlusion of bilateral common carotid artery (CCA) combined with permanent occlusion of middle cerebral artery (MCA); delayed postconditioning was performed by repetitive, brief occlusion and release of the bilateral CCAs, or of the ipsilateral CCA alone. As a result, delayed postconditioning performed at 3h and 6h after stroke robustly reduced infarct size, with the strongest protection achieved by delayed postconditioning with 6 cycles of 15 min occlusion/15 min release of the ipsilateral CCA executed from 6h. We found that this delayed postconditioning provided long-term protection for up to two months by reducing infarction and improving outcomes of the behavioral tests; it also attenuated reduction in 2-[18F]-fluoro-2-deoxy-D-glucose (FDG)-uptake therefore improving metabolism, and reduced edema and blood brain barrier leakage. Reperfusion in ischemic stroke patients is usually achieved by tissue plasminogen activator (tPA) application, however, t-PA's side effect may worsen ischemic injury. Thus, we tested whether delayed postconditioning counteracts the exacerbating effect of t-PA. The results showed that delayed postconditioning mitigated the worsening effect of t-PA on infarction. Conclusion Delayed postconditioning reduced ischemic injury after focal ischemia, which opens a new research avenue for stroke therapy and its underlying protective mechanisms. PMID:19066627

  16. HCaRG Accelerates Tubular Repair after Ischemic Kidney Injury

    PubMed Central

    Matsuda, Hiroyuki; Lavoie, Julie L.; Gaboury, Louis; Hamet, Pavel

    2011-01-01

    The repair of the kidney after ischemia/reperfusion injury involves proliferation of proximal tubular epithelial cells as well as cell migration and differentiation. Immediately after reperfusion, expression of hypertension-related calcium-regulated gene (HCaRG/COMMD5) decreases, but its expression increases even higher than baseline during repair. HCaRG inhibits proliferation and accelerates wound healing and differentiation in cultured cells, but whether HCaRG can stimulate renal repair after ischemia/reperfusion injury is unknown. Here, transgenic mice overexpressing human HCaRG survived longer and recovered renal function faster than littermate controls after ischemia/reperfusion (64% versus 25% survival at 7 days). Proliferation of proximal tubular epithelial cells stopped earlier after ischemia/reperfusion injury, E-cadherin levels recovered more rapidly, and vimentin induction abated faster in transgenic mice. HCaRG overexpression also reduced macrophage infiltration and inflammation after injury. Taken together, these data suggest that HCaRG accelerates repair of renal proximal tubules by modulating cell proliferation of resident tubular epithelial cells and by facilitating redifferentiation. PMID:21921141

  17. Predominant role for C5b-9 in renal ischemia/reperfusion injury

    PubMed Central

    Zhou, Wuding; Farrar, Conrad A.; Abe, Katsushige; Pratt, Julian R.; Marsh, James E.; Wang, Yi; Stahl, Gregory L.; Sacks, Steven H.

    2000-01-01

    Previous work has indicated that complement is a mediator of ischemia/reperfusion (I/R) injury. To investigate the components of complement responsible for this effect, we examined a model of renal I/R injury in C3-, C4-, C5-, and C6-deficient mice. We occluded the renal arteries and veins (40–58 minutes) and, after reperfusion (0–72 hours), assessed renal structural and functional injury. C3-, C5-, and C6-deficient mice were protected from renal I/R injury, whereas C4-deficient mice were not protected. C6-deficient mice treated with antibody to block C5a generation showed no additional protection from I/R injury. Reconstitution with C6 alone restored the I/R injury in C6-deficient mice. Tubular epithelial cells were the main structures damaged by complement-mediated attack, and, in contrast, the renal vessels were spared. Neutrophil infiltration and myeloperoxidase activity were reduced in C-deficient mouse kidney, but by a similar extent in C3-deficient and C6-deficient mice. We conclude that the membrane attack complex of complement (in which C5 and C6 participate) may account for the effect of complement on mouse renal I/R injury. Neither C5a-mediated neutrophil infiltration nor the classic pathway, in which C4 participates, appears to contribute to I/R injury in this model. By contrast with other organs, such as the heart, the primary effect of complement in the ischemic area is on the parenchymal cell rather than the vascular endothelial cell. The membrane attack complex of complement is a potential target for prevention of I/R injury in this model. PMID:10811844

  18. The volatile anesthetic isoflurane induces ecto-5′-nucleotidase (CD73) to protect against renal ischemia and reperfusion injury

    PubMed Central

    Kim, Mihwa; Ham, Ahrom; Kim, Joo Yun; Brown, Kevin M.; D’Agati, Vivette D.; Lee, H. Thomas

    2013-01-01

    The volatile anesthetic isoflurane protects against renal ischemia and reperfusion injury by releasing renal tubular TGF-β1. Since adenosine is a powerful cytoprotective molecule, we tested whether TGF-β1 generated by isoflurane induces renal tubular ecto-5′-nucleotidase (CD73) and adenosine to protect against renal ischemia and reperfusion injury. Isoflurane induced new CD73 synthesis and increased adenosine generation in cultured kidney proximal tubule cells and in mouse kidney. Moreover, a TGF-β1 neutralizing antibody prevented isoflurane-mediated induction of CD73 activity. Mice anesthetized with isoflurane after renal ischemia and reperfusion had significantly reduced plasma creatinine and decreased renal tubular necrosis, neutrophil infiltration and apoptosis compared to pentobarbital-anesthetized mice. Isoflurane failed to protect against renal ischemia and reperfusion injury in CD73 deficient mice, in mice pretreated with a selective CD73 inhibitor or mice treated with an adenosine receptor antagonist. The TGF-β1 neutralizing antibody or the CD73 inhibitor attenuated isoflurane-mediated protection against HK-2 cell apoptosis. Thus, isoflurane causes TGF-β1-dependent induction of renal tubular CD73 and adenosine generation to protect against renal ischemia and reperfusion injury. Modulation of this pathway may have important therapeutic implications to reduce morbidity and mortality arising from ischemic acute kidney injury. PMID:23423261

  19. Myricetin and quercetin attenuate ischemic injury in glial cultures by different mechanisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have demonstrated that polyphenols from cinnamon and green tea reduce cell swelling and mitochondrial dysfunction in C6 glial cultures following ischemic injury. We tested the protective effects of the flavonoid polyphenols, myricetin and quercetin, on key features of ischemic injury. C6 cultures...

  20. Suppression of Etk/Bmx protects against ischemic brain injury.

    PubMed

    Chen, Kai-Yun; Wu, Chung-Che; Chang, Cheng-Fu; Chen, Yuan-Hao; Chiu, Wen-Ta; Lou, Ya-Hsin; Chen, Yen-Hua; Shih, Hsiu-Ming; Chiang, Yung-Hsiao

    2012-01-01

    Etk/Bmx (epithelial and endothelial tyrosine kinase, also known as BMX), a member of the Tec (tyrosine kinase expressed in hepatocellular carcinoma) family of protein-tyrosine kinases, is an important regulator of signal transduction for the activation of cell growth, differentiation, and development. We have previously reported that activation of Etk leads to apoptosis in MDA-MB-468 cells. The purpose of this study was to examine the role of Etk in neuronal injury induced by H(2)O(2) or ischemia. Using Western blot analysis and immunohistochemistry, we found that treatment with H(2)O(2) significantly enhanced phosphorylation of Etk and its downstream signaling molecule Stat1 in primary cortical neurons. Inhibiting Etk activity by LFM-A13 or knocking down Etk expression by a specific shRNA increased the survival of primary cortical neurons. Similarly, at 1 day after a 60-min middle cerebral artery occlusion (MCAo) in adult rats, both phosphorylated Etk and Stat1 were coexpressed with apoptotic markers in neurons in the penumbra. Pretreatment with LFM-A13 or an adenoviral vector encoding the kinase deletion mutant Etkk attenuated caspase-3 activity and infarct volume in ischemic brain. All together, our data suggest that Etk is activated after neuronal injury. Suppressing Etk activity protects against neurodegeneration in ischemic brain. PMID:21929872

  1. Intestinal ischemic preconditioning reduces liver ischemia reperfusion injury in rats

    PubMed Central

    XUE, TONG-MIN; TAO, LI-DE; ZHANG, JIE; ZHANG, PEI-JIAN; LIU, XIA; CHEN, GUO-FENG; ZHU, YI-JIA

    2016-01-01

    The aim of the current study was to investigate whether intestinal ischemic preconditioning (IP) reduces damage to the liver during hepatic ischemia reperfusion (IR). Sprague Dawley rats were used to model liver IR injury, and were divided into the sham operation group (SO), IR group and IP group. The results indicated that IR significantly increased Bax, caspase 3 and NF-κBp65 expression levels, with reduced expression of Bcl-2 compared with the IP group. Compared with the IR group, the levels of AST, ALT, MPO, MDA, TNF-α and IL-1 were significantly reduced in the IP group. Immunohistochemistry for Bcl-2 and Bax indicated that Bcl-2 expression in the IP group was significantly increased compared with the IR group. In addition, IP reduced Bax expression compared with the IR group. The average liver injury was worsened in the IR group and improved in the IP group, as indicated by the morphological evaluation of liver tissues. The present study suggested that IP may alleviates apoptosis, reduce the release of pro-inflammatory cytokines, ameloriate reductions in liver function and reduce liver tissue injury. To conclude, IP provided protection against hepatic IR injury. PMID:26821057

  2. Update in the classification and treatment of complex renal injuries.

    PubMed

    Reis, Leonardo Oliveira; Kim, Fernando J; Moore, Ernest E; Hirano, Elcio Shiyoiti; Fraga, Gustavo Pereira; Nascimento, Barto; Rizoli, Sandro

    2013-01-01

    The "Evidence-Based Telemedicine - Trauma and Acute Care Surgery" (EBT-TACS) Journal Club performed a critical review of the literature and selected three up-to-date articles on the management of renal trauma defined as American Association for the Surgery of Trauma (AAST) injury grade III-V. The first paper was the proposal for the AAST grade 4renal injury substratification into grades 4a (Low Risk) and 4b (High Risk). The second paper was a revision of the current AAST renal injury grading system, expanding to include segmental vascular injuries and to establish a more rigorous definition of severe grade IV and V renal injuries.The last article analyses the diagnostic angiography and angioembolization in the acute management of renal trauma using a national data set in the USA. The EBT-TACS Journal Club elaborated conclusions and recommendations for the management of high-grade renal trauma. PMID:24173488

  3. Trans-system mechanisms against ischemic myocardial injury.

    PubMed

    Liu, Shu Q; Ma, Xin-Liang; Qin, Gangjian; Liu, Qingping; Li, Yan-Chun; Wu, Yu H

    2015-01-01

    A mammalian organism possesses a hierarchy of naturally evolved protective mechanisms against ischemic myocardial injury at the molecular, cellular, and organ levels. These mechanisms comprise regional protective processes, including upregulation and secretion of paracrine cell-survival factors, inflammation, angiogenesis, fibrosis, and resident stem cell-based cardiomyocyte regeneration. There are also interactive protective processes between the injured heart, circulation, and selected remote organs, defined as trans-system protective mechanisms, including upregulation and secretion of endocrine cell-survival factors from the liver and adipose tissue as well as mobilization of bone marrow, splenic, and hepatic cells to the injury site to mediate myocardial protection and repair. The injured heart and activated remote organs exploit molecular and cellular processes, including signal transduction, gene expression, cell proliferation, differentiation, migration, mobilization, and/or extracellular matrix production, to establish protective mechanisms. Both regional and trans-system cardioprotective mechanisms are mediated by paracrine and endocrine messengers and act in coordination and synergy to maximize the protective effect, minimize myocardial infarction, and improve myocardial function, ensuring the survival and timely repair of the injured heart. The concept of the trans-system protective mechanisms may be generalized to other organ systems-injury in one organ may initiate regional as well as trans-system protective responses, thereby minimizing injury and ensuring the survival of the entire organism. Selected trans-system processes may serve as core protective mechanisms that can be exploited by selected organs in injury. These naturally evolved protective mechanisms are the foundation for developing protective strategies for myocardial infarction and injury-induced disorders in other organ systems. PMID:25589268

  4. RGS4 inhibits angiotensin II signaling and macrophage localization during renal reperfusion injury independent of vasospasm

    PubMed Central

    Pang, Paul; Jin, Xiaohua; Proctor, Brandon M.; Farley, Michelle; Roy, Nilay; Chin, Matthew S.; von Andrian, Ulrich H.; Vollmann, Elisabeth; Perro, Mario; Hoffman, Ryan J.; Chung, Joseph; Chauhan, Nikita; Mistri, Murti; Muslin, Anthony J.; Bonventre, Joseph V.; Siedlecki, Andrew M.

    2014-01-01

    Vascular inflammation is a major contributor to the severity of acute kidney injury. In the context of vasospasm-independent reperfusion injury we studied the potential anti-inflammatory role of the Gα-related RGS protein, RGS4. Transgenic RGS4 mice were resistant to 25 minute injury, although post-ischemic renal arteriolar diameter was equal to the wild type early after injury. A 10 minute unilateral injury was performed to study reperfusion without vasospasm. Eighteen hours after injury blood flow was decreased in the inner cortex of wild type mice with preservation of tubular architecture. Angiotensin II levels in the kidneys of wild type and transgenic mice were elevated in a sub-vasoconstrictive range 12 and 18 hours after injury. Angiotensin II stimulated pre-glomerular vascular smooth muscle cells (VSMC) to secrete the macrophage chemoattractant, RANTES; a process decreased by angiotensin II R2 (AT2) inhibition. However, RANTES increased when RGS4 expression was suppressed implicating Gα protein activation in an AT2-RGS4-dependent pathway. RGS4 function, specific to VSMC, was tested in a conditional VSMC-specific RGS4 knockout showing high macrophage density by T2 MRI compared to transgenic and non-transgenic mice after the 10 minute injury. Arteriolar diameter of this knockout was unchanged at successive time points after injury. Thus, RGS4 expression, specific to renal VSMC, inhibits angiotensin II-mediated cytokine signaling and macrophage recruitment during reperfusion, distinct from vasomotor regulation. PMID:25469849

  5. Urinary Calprotectin and Posttransplant Renal Allograft Injury

    PubMed Central

    Bistrup, Claus; Marcussen, Niels; Pagonas, Nikolaos; Seibert, Felix S.; Arndt, Robert; Zidek, Walter; Westhoff, Timm H.

    2014-01-01

    Objective Current methods do not predict the acute renal allograft injury immediately after kidney transplantation. We evaluated the diagnostic performance of urinary calprotectin for predicting immediate posttransplant allograft injury. Methods In a multicenter, prospective-cohort study of 144 incipient renal transplant recipients, we postoperatively measured urinary calprotectin using an enzyme-linked immunosorbent assay and estimated glomerular filtration rate (eGFR) after 4 weeks, 6 months, and 12 months. Results We observed a significant inverse association of urinary calprotectin concentrations and eGFR 4 weeks after transplantation (Spearman r = −0.33; P<0.001). Compared to the lowest quartile, patients in the highest quartile of urinary calprotectin had an increased risk for an eGFR less than 30 mL/min/1.73 m2 four weeks after transplantation (relative risk, 4.3; P<0.001; sensitivity, 0.92; 95% CI, 0.77 to 0.98; specificity, 0.48; 95% CI, 0.31 to 0.66). Higher urinary calprotectin concentrations predicted impaired kidney function 4 weeks after transplantation, as well as 6 months and 12 months after transplantation. When data were analyzed using the urinary calprotectin/creatinine-ratio similar results were obtained. Urinary calprotectin was superior to current use of absolute change of plasma creatinine to predict allograft function 12 months after transplantation. Urinary calprotectin predicted an increased risk both in transplants from living and deceased donors. Multivariate linear regression showed that higher urinary calprotectin concentrations and older donor age predicted lower eGFR four weeks, 6 months, and 12 months after transplantation. Conclusions Urinary calprotectin is an early, noninvasive predictor of immediate renal allograft injury after kidney transplantation. PMID:25402277

  6. Renal rescue of dopamine D2 receptor function reverses renal injury and high blood pressure

    PubMed Central

    Konkalmatt, Prasad R.; Asico, Laureano D.; Zhang, Yanrong; Yang, Yu; Drachenberg, Cinthia; Zheng, Xiaoxu; Han, Fei; Jose, Pedro A.; Armando, Ines

    2016-01-01

    Dopamine D2 receptor (DRD2) deficiency increases renal inflammation and blood pressure in mice. We show here that long-term renal-selective silencing of Drd2 using siRNA increases renal expression of proinflammatory and profibrotic factors and blood pressure in mice. To determine the effects of renal-selective rescue of Drd2 expression in mice, the renal expression of DRD2 was first silenced using siRNA and 14 days later rescued by retrograde renal infusion of adeno-associated virus (AAV) vector with DRD2. Renal Drd2 siRNA treatment decreased the renal expression of DRD2 protein by 55%, and DRD2 AAV treatment increased the renal expression of DRD2 protein by 7.5- to 10-fold. Renal-selective DRD2 rescue reduced the expression of proinflammatory factors and kidney injury, preserved renal function, and normalized systolic and diastolic blood pressure. These results demonstrate that the deleterious effects of renal-selective Drd2 silencing on renal function and blood pressure were rescued by renal-selective overexpression of DRD2. Moreover, the deleterious effects of 45-minute bilateral ischemia/reperfusion on renal function and blood pressure in mice were ameliorated by a renal-selective increase in DRD2 expression by the retrograde ureteral infusion of DRD2 AAV immediately after the induction of ischemia/reperfusion injury. Thus, 14 days after ischemia/reperfusion injury, the renal expression of profibrotic factors, serum creatinine, and blood pressure were lower in mice infused with DRD2 AAV than in those infused with control AAV. These results indicate an important role of renal DRD2 in limiting renal injury and preserving normal renal function and blood pressure. PMID:27358912

  7. Estrogenic Impact on Cardiac Ischemic/Reperfusion Injury.

    PubMed

    Sivasinprasasn, Sivaporn; Shinlapawittayatorn, Krekwit; Chattipakorn, Siriporn C; Chattipakorn, Nipon

    2016-02-01

    The increase in cardiovascular disease and metabolic syndrome incidence following the onset of menopause has highlighted the role of estrogen as a cardiometabolic protective agent. Specifically regarding the heart, estrogen induced an improvement in cardiac function, preserved calcium homeostasis, and inhibited the mitochondrial apoptotic pathway. The beneficial effects of estrogen in relation to cardiac ischemia/reperfusion (I/R) injury, such as reduced infarction and ameliorated post-ischemic recovery, have also been shown. Nevertheless, controversial findings exist and estrogen therapy is reported to be related to a higher rate of thromboembolic events and atrial fibrillation in post-menopausal women. Therefore, greater clarification is needed to evaluate the exact potential of estrogen use in cases of cardiac I/R injury. This article reviews the effects of estrogen, in both acute and chronic treatment, and collates the studies with regard to their in vivo, in vitro, or clinical trial settings in cases of cardiac I/R injury and myocardial infarction. PMID:26786980

  8. Cardioprotection against experimental myocardial ischemic injury using cornin

    PubMed Central

    Xu, Y.; Xu, Y.; Luan, H.; Jiang, Y.; Tian, X.; Zhang, S.

    2016-01-01

    Phosphorylated-cyclic adenosine monophosphate response element-binding protein (Phospho-CREB) has an important role in the pathogenesis of myocardial ischemia. We isolated the iridoid glycoside cornin from the fruit of Verbena officinalis L, investigated its effects against myocardial ischemia and reperfusion (I/R) injury in vivo, and elucidated its potential mechanism in vitro. Effects of cornin on cell viability, as well as expression of phospho-CREB and phospho-Akt in hypoxic H9c2 cells in vitro, and myocardial I/R injury in vivo, were investigated. Cornin attenuated hypoxia-induced cytotoxicity significantly in H9c2 cells in a concentration-dependent manner. Treatment of H9c2 cells with cornin (10 µM) blocked the reduction of expression of phospho-CREB and phospho-Akt in a hypoxic condition. Treatment of rats with cornin (30 mg/kg, iv) protected them from myocardial I/R injury as indicated by a decrease in infarct volume, improvement in hemodynamics, and reduction of severity of myocardial damage. Cornin treatment also attenuated the reduction of expression of phospho-CREB and phospho-Akt in ischemic myocardial tissue. These data suggest that cornin exerts protective effects due to an increase in expression of phospho-CREB and phospho-Akt. PMID:26871971

  9. Cardioprotection against experimental myocardial ischemic injury using cornin.

    PubMed

    Xu, Y; Xu, Y; Luan, H; Jiang, Y; Tian, X; Zhang, S

    2016-02-01

    Phosphorylated-cyclic adenosine monophosphate response element-binding protein (Phospho-CREB) has an important role in the pathogenesis of myocardial ischemia. We isolated the iridoid glycoside cornin from the fruit of Verbena officinalis L, investigated its effects against myocardial ischemia and reperfusion (I/R) injury in vivo, and elucidated its potential mechanism in vitro. Effects of cornin on cell viability, as well as expression of phospho-CREB and phospho-Akt in hypoxic H9c2 cells in vitro, and myocardial I/R injury in vivo, were investigated. Cornin attenuated hypoxia-induced cytotoxicity significantly in H9c2 cells in a concentration-dependent manner. Treatment of H9c2 cells with cornin (10 µM) blocked the reduction of expression of phospho-CREB and phospho-Akt in a hypoxic condition. Treatment of rats with cornin (30 mg/kg, iv) protected them from myocardial I/R injury as indicated by a decrease in infarct volume, improvement in hemodynamics, and reduction of severity of myocardial damage. Cornin treatment also attenuated the reduction of expression of phospho-CREB and phospho-Akt in ischemic myocardial tissue. These data suggest that cornin exerts protective effects due to an increase in expression of phospho-CREB and phospho-Akt. PMID:26871971

  10. Critical Role of Interleukin-11 in Isoflurane-mediated Protection against Ischemic Acute Kidney Injury in Mice

    PubMed Central

    Ham, Ahrom; Kim, Mihwa; Kim, Joo Yun; Brown, Kevin M.; Yeh, James; D’Agati, Vivette D.; Lee, H. Thomas

    2013-01-01

    Background Isoflurane releases renal tubular transforming growth factor-beta 1 (TGF-β1) and protects against ischemic acute kidney injury (AKI). Recent studies suggest that TGF-β1 can induce a cytoprotective cytokine interleukin (IL)-11. Here, we tested the hypothesis that isoflurane protects against ischemic AKI by direct induction of renal tubular IL-11 synthesis. Methods Human kidney proximal tubule (HK-2) cells were treated with 1.25-2.5% isoflurane or carrier gas (room air+5% carbon dioxide) for 0-16 h. We also anesthetized C57BL/6 mice with 1.2% isoflurane or with equi-anesthetic dose of pentobarbital for 4 h. In addition, we subjected IL-11 receptor (IL-11R) wild type, IL-11R deficient or IL-11 neutralized mice to 30-min renal ischemia followed by reperfusion under 4 h of pentobarbital or isoflurane (1.2%) anesthesia. Results Isoflurane increased IL-11 synthesis in human (~300-500% increase, N = 6) and mouse (23 ± 4 (mean ± SD) fold over carrier gas group, N = 4) proximal tubule cells that were attenuated by a TGF-β1 neutralizing antibody. Mice anesthetized with isoflurane showed significantly increased kidney IL-11 messenger RNA (13.8 ± 2 fold over carrier gas group, N = 4) and protein (31 ± 9 vs. 18±2 pg/mg protein or ~80% increase, N = 4) expression compared to pentobarbital anesthetized mice and this increase was also attenuated by a TGF-β1 neutralizing antibody. Furthermore, isoflurane-mediated renal protection in IL-11R wild-type mice were absent in IL-11R deficient mice or in IL-11R wild-type mice treated with IL-11 neutralizing antibody (N = 4-6). Conclusions Our studies suggest that isoflurane induces renal tubular IL-11 via TGF-β1 signaling to protect against ischemic AKI. PMID:24037316

  11. Pre-ischemic treadmill training for prevention of ischemic brain injury via regulation of glutamate and its transporter GLT-1.

    PubMed

    Yang, Xiaojiao; He, Zhijie; Zhang, Qi; Wu, Yi; Hu, Yongshan; Wang, Xiaolou; Li, Mingfen; Wu, Zhiyuan; Guo, Zhenzhen; Guo, Jingchun; Jia, Jie

    2012-01-01

    Pre-ischemic treadmill training exerts cerebral protection in the prevention of cerebral ischemia by alleviating neurotoxicity induced by excessive glutamate release following ischemic stroke. However, the underlying mechanism of this process remains unclear. Cerebral ischemia-reperfusion injury was observed in a rat model after 2 weeks of pre-ischemic treadmill training. Cerebrospinal fluid was collected using the microdialysis sampling method, and the concentration of glutamate was determined every 40 min from the beginning of ischemia to 4 h after reperfusion with high-performance liquid chromatography (HPLC)-fluorescence detection. At 3, 12, 24, and 48 h after ischemia, the expression of the glutamate transporter-1 (GLT-1) protein in brain tissues was determined by Western blot respectively. The effect of pre-ischemic treadmill training on glutamate concentration and GLT-1 expression after cerebral ischemia in rats along with changes in neurobehavioral score and cerebral infarct volume after 24 h ischemia yields critical information necessary to understand the protection mechanism exhibited by pre-ischemic treadmill training. The results demonstrated that pre-ischemic treadmill training up-regulates GLT-1 expression, decreases extracellular glutamate concentration, reduces cerebral infarct volume, and improves neurobehavioral score. Pre-ischemic treadmill training is likely to induce neuroprotection after cerebral ischemia by regulating GLT-1 expression, which results in re-uptake of excessive glutamate. PMID:22949807

  12. Importance of adenosine triphosphate in phospholipase A2-induced rabbit renal proximal tubule cell injury.

    PubMed Central

    Nguyen, V D; Cieslinski, D A; Humes, H D

    1988-01-01

    The pathogenesis of ischemic renal tubular cell injury involves a complex interaction of different processes, including membrane phospholipid alterations and depletion of high-energy phosphate stores. To assess the role of membrane phospholipid changes due to activation of phospholipases in renal tubule cell injury, suspensions enriched in rabbit renal proximal tubule segments were incubated with exogenous phospholipase A2 (PLA2). Exogenous PLA2 did not produce any significant change in various metabolic parameters reflective of cell injury in control nonhypoxic preparations despite a significant decrease in phosphatidylethanolamine (PE) and moderate increases in lysophosphatidylcholine (LPC) and lysophosphatidylethanolamine (LPE). In contrast, exogenous PLA2 treatment of hypoxic tubules resulted in a severe degree of cell injury, as demonstrated by marked declines in tubule K+ and ATP contents and significant decreases in tubule uncoupled respiratory rates, and was associated with significant phospholipid alterations, including marked declines in phosphatidylcholine (PC) and PE and significant rises in LPC, LPE, and free fatty acids (FFA). The injurious metabolic effects of exogenous PLA2 on hypoxic tubules were reversed by addition of ATP-MgCl2 to the tubules. The protective effect of ATP-MgCl2 was associated with increases in tubule PC and PE contents and declines in LPC, LPE, and FFA contents. These experiments thus indicate that an increase in exogenous PLA2 activity produces renal proximal tubule cell injury when cell ATP levels decline, at which point phospholipid resynthesis cannot keep pace with phospholipid degradation with resulting depletion of phospholipids and accumulation of lipid by-products. High-energy phosphate store depletion appears to be an important condition for exogenous PLA2 activity to induce renal tubule cell injury. PMID:3417866

  13. Fructokinase activity mediates dehydration-induced renal injury.

    PubMed

    Roncal Jimenez, Carlos A; Ishimoto, Takuji; Lanaspa, Miguel A; Rivard, Christopher J; Nakagawa, Takahiko; Ejaz, A Ahsan; Cicerchi, Christina; Inaba, Shinichiro; Le, MyPhuong; Miyazaki, Makoto; Glaser, Jason; Correa-Rotter, Ricardo; González, Marvin A; Aragón, Aurora; Wesseling, Catharina; Sánchez-Lozada, Laura G; Johnson, Richard J

    2014-08-01

    The epidemic of chronic kidney disease in Nicaragua (Mesoamerican nephropathy) has been linked with recurrent dehydration. Here we tested whether recurrent dehydration may cause renal injury by activation of the polyol pathway, resulting in the generation of endogenous fructose in the kidney that might subsequently induce renal injury via metabolism by fructokinase. Wild-type and fructokinase-deficient mice were subjected to recurrent heat-induced dehydration. One group of each genotype was provided water throughout the day and the other group was hydrated at night, after the dehydration. Both groups received the same total hydration in 24 h. Wild-type mice that received delayed hydration developed renal injury, with elevated serum creatinine, increased urinary NGAL, proximal tubular injury, and renal inflammation and fibrosis. This was associated with activation of the polyol pathway, with increased renal cortical sorbitol and fructose levels. Fructokinase-knockout mice with delayed hydration were protected from renal injury. Thus, recurrent dehydration can induce renal injury via a fructokinase-dependent mechanism, likely from the generation of endogenous fructose via the polyol pathway. Access to sufficient water during the dehydration period can protect mice from developing renal injury. These studies provide a potential mechanism for Mesoamerican nephropathy. PMID:24336030

  14. Comparison of biomarkers in rat renal ischemia-reperfusion injury.

    PubMed

    Peng, Hongying; Mao, Yan; Fu, Xiaoya; Feng, Zhipeng; Xu, Jun

    2015-01-01

    To observe the expressions of monocyte chemoattractant protein -l (MCP-l), kidney injury molecule -l (KIM-l) and cystatin C (Cys C) in different periods of rat ischemic acute kidney injury (iAKI). The rat renal ischemia-reperfusion injury (IRI) model was prepared, including the sham-operation (Sham) group and the I/R group. The specimens were collected at different time points after iAKI. The expressions of MCP-1, KIM-1 and Cys C of the I/R group were increased earlier than Scr and Urea (I/R group vs. Sham group; P < 0.01). The serum MCP-1 of the I/R group was earliest increased (MCP-1 vs. KIM-1, Cys C and Scr, P < 0.01). Followed by KIM-1 and Cys C; and in the urine samples, the KIM-1 expression was the most sensitive (KIM-1 vs. MCP-1, Cys C and Scr, P < 0.01). The immunohistochemical results showed the kidney of the Sham group almost had no expression, while that of the I/R group significantly expressed MCP-1, KIM-1 and Cys C (I/R group vs. Sham group; P < 0.01). MCP-1, KIM-1 and Cys C had important predictive values towards AKI, and MCP-1 and KIM-1 were superior to Cys C. Different biomarkers had different sensitivities: MCP-1 was earliest increased in serum while lasted shortly, KIM-1 was earliest increased in urine and kept increasing, thus the detection of urinary KIM-1 might be much more suitable in clinics. PMID:26221302

  15. Effect of melatonin on kidney cold ischemic preservation injury

    PubMed Central

    Aslaner, Arif; Gunal, Omer; Turgut, Hamdi Taner; Celik, Erdal; Yildirim, Umran; Demirci, Rojbin Karakoyun; Gunduz, Umut Riza; Calis, Hasan; Dogan, Sami

    2013-01-01

    Melatonin is a potent free radical scavenger of reactive oxygen species, nitric oxide synthase inhibitor and a well-known antioxidant secreted from pineal gland. This hormone has been reported to protect tissue from oxidative damage. In this study, we aim to investigate the effect of melatonin on kidney cold ischemia time when added to preservation solution. Thirty male Wistar albino rats were divided equally into three groups; Ringer Lactate (RL) solution, University of Wisconsin (UW) solution with and without melatonin. The serum Lactate Dehydrogenase (LDH) activities of the preservation solutions at 2nd, 24th, 36th, and 48th hours were determined. Tissue malondialdehyde (MDA) levels were also measured and a histological examination was performed at 48th hour. Melatonin that added to preservation solution prevented enzyme elevation and decreased lipid peroxidation in preservation solution when compared to the control group (p<0.05). The histological examination revealed that UW solution containing melatonin significantly prevented the kidney from pathological injury (p<0.05). Melatonin added to preservation solutions such as UW solution seemed to protect the tissue preserved effectively from cold ischemic injury for up to 48 hour. PMID:24179573

  16. The multifaceted role of the renal microvasculature during acute kidney injury.

    PubMed

    Maringer, Katherine; Sims-Lucas, Sunder

    2016-08-01

    Pediatric acute kidney injury (AKI) represents a complex disease process for clinicians as it is multifactorial in cause and only limited treatment or preventatives are available. The renal microvasculature has recently been implicated in AKI as a strong therapeutic candidate involved in both injury and recovery. Significant progress has been made in the ability to study the renal microvasculature following ischemic AKI and its role in repair. Advances have also been made in elucidating cell-cell interactions and the molecular mechanisms involved in these interactions. The ability of the kidney to repair post AKI is closely linked to alterations in hypoxia, and these studies are elucidated in this review. Injury to the microvasculature following AKI plays an integral role in mediating the inflammatory response, thereby complicating potential therapeutics. However, recent work with experimental animal models suggests that the endothelium and its cellular and molecular interactions are attractive targets to prevent injury or hasten repair following AKI. Here, we review the cellular and molecular mechanisms of the renal endothelium in AKI, as well as repair and recovery, and potential therapeutics to prevent or ameliorate injury and hasten repair. PMID:26493067

  17. Neurotoxic lipid peroxidation species formed by ischemic stroke increase injury

    PubMed Central

    Zeiger, Stephanie L. H.; Musiek, Erik S.; Zanoni, Giuseppe; Vidari, Giovanni; Morrow, Jason D.; Milne, Ginger J.; McLaughlin, BethAnn

    2009-01-01

    Stroke is the third leading cause of death in the United States yet no neuroprotective agents for treatment are clinically available. There is a pressing need to understand the signaling molecules which mediate ischemic cell death and identify novel neuroprotective targets. Cyclopentenone isoprostanes (IsoP), formed following free radical mediated peroxidation of arachidonic acid, are used as markers of stress but their bioactivity is poorly understood. We have recently shown that 15-A2t-Isop is a potent neurotoxin in vitro and increases the free radical burden in neurons. In this work, we demonstrate that 15-A2t-IsoP is abundantly produced in stroke infarcted human cortical tissue. Using primary neuronal cultures we found that minimally toxic exposure to 15-A2t-IsoP does not alter ATP content, but in combination with oxygen glucose deprivation resulted in a significant hyperpolarization of the mitochondrial membrane and dramatically increased neuronal cell death. In the presence of Ca2+, 15-A2t-IsoP led to a rapid induction of the permeability transition pore and release of cytochrome c. Taken with our previous work, these data support a model in which ischemia causes generation of reactive oxygen species, calcium influx, lipid peroxidation and 15-A2t-IsoP formation. These factors combine to enhance opening of the permeability transition pore leading to cell death subsequent to mitochondrial cytochrome c release. This data is the first documentation of significant 15-A2t-IsoP formation following acute ischemic stroke and suggests addition of 15-A2t-IsoP to in vitro models of ischemia may help to more fully recapitulate stroke injury. PMID:19699297

  18. Renal Trauma from Recreational Accidents Manifests Different Injury Patterns than Urban Renal Trauma

    PubMed Central

    Lloyd, Granville L.; Slack, Sean; McWilliams, Kelly L.; Black, Aaron; Nicholson, Tristan M.

    2013-01-01

    Purpose The majority of blunt renal trauma is a consequence of motor vehicle collisions and falls. Prior publications based on urban series have shown that significant renal injuries are almost always accompanied by gross hematuria alone or microscopic hematuria with concomitant hypotension. We present a series of blunt renal trauma sustained during recreational pursuits, and describe the mechanisms, injury patterns and management. Materials and Methods Database review from 1996 to 2009 identified 145 renal injuries. Children younger than age 16 years, and trauma involving licensable motor vehicles, penetrating injuries and work related injuries were excluded from analysis. Grade, hematuria, hypotension, age, gender, laterality, mechanism, management, injury severity score and associated injuries were recorded. Results We identified 106 patients meeting the criteria and 85% of the injuries were snow sport related. Age range was 16 to 76 years and 92.5% of patients were male. There were 39 grade 1 injuries, 30 grade 2, 22 grade 3, 12 grade 4 and 3 grade 5 injuries. Gross hematuria was present in 56.7%, 77.2% and 83.3% of grade 2, grade 3 and grade 4 injuries, respectively. None of the patients with grade 2 or greater injuries and microscopic hematuria had hypotension except 1 grade 5 pedicle injury. The nephrectomy and renorrhaphy rate for grade 1 to grade 4 injuries was 0%. Conclusions Compared to urban series of blunt renal trauma, recreationally acquired injuries appear to follow different patterns, including a paucity of associated injuries or hypotension. If imaging were limited to the presence of gross hematuria, or microscopic hematuria with hypotension, 23% of grade 2 to grade 4 injuries would be missed. Men are at higher risk than women. However, operative intervention is rarely helpful. PMID:22591969

  19. Galacto-oligosaccharides attenuate renal injury with microbiota modification.

    PubMed

    Furuse, Satoshi U; Ohse, Takamoto; Jo-Watanabe, Airi; Shigehisa, Akira; Kawakami, Koji; Matsuki, Takahiro; Chonan, Osamu; Nangaku, Masaomi

    2014-07-01

    Tubulointerstitial injury is central to the progression of end-stage renal disease. Recent studies have revealed that one of the most investigated uremic toxins, indoxyl sulfate (IS), caused tubulointerstitial injury through oxidative stress and endoplasmic reticulum (ER) stress. Because indole, the precursor of IS, is synthesized from dietary tryptophan by the gut microbiota, we hypothesized that the intervention targeting the gut microbiota in kidney disease with galacto-oligosaccharides (GOS) would attenuate renal injury. After 2 weeks of GOS administration for 5/6 nephrectomized (Nx) or sham-operated (Sham) rats, cecal indole and serum IS were measured, renal injury was evaluated, and the effects of GOS on the gut microbiota were examined using pyrosequencing methods. Cecal indole and serum IS were significantly decreased and renal injury was improved with decreased infiltrating macrophages in GOS-treated Nx rats. The expression levels of ER stress markers and apoptosis were significantly increased in the Nx rats and decreased with GOS. The microbiota analysis indicated that GOS significantly increased three bacterial families and decreased five families in the Nx rats. In addition, the analysis also revealed that the bacterial family Clostridiaceae was significantly increased in the Nx rats compared with the Sham rats and decreased with GOS. Taken altogether, our data show that GOS decreased cecal indole and serum IS, attenuated renal injury, and modified the gut microbiota in the Nx rats, and that the gut microbiota were altered in kidney disease. GOS could be a novel therapeutic agent to protect against renal injury. PMID:24994892

  20. Role of Mitochondria in Neonatal Hypoxic-Ischemic Brain Injury

    PubMed Central

    Lu, Yujiao; Tucker, Donovan; Dong, Yan; Zhao, Ningjun; Zhuo, Xiaoying; Zhang, Quanguang

    2016-01-01

    Hypoxic-ischemia (HI) causes severe brain injury in neonates. It’s one of the leading causes to neonatal death and pediatric disability, resulting in devastating consequences, emotionally and economically, to their families. A series of events happens in this process, e.g. excitatory transmitter release, extracelluar Ca2+ influxing, mitochondrial dysfunction, energy failure, and neuron death. There are two forms of neuron death after HI insult: necrosis and apoptosis, apoptosis being the more prevalent form. Mitochondria handle a series of oxidative reactions, and yield energy for various cellular activities including the maintainance of membrane potential and preservation of intracellular ionic homeostasis. Therefore mitochondria play a critical role in neonatal neurodegeneration following HI, and mitochondrial dysfunction is the key point in neurodegenerative evolution. Because of this, exploring effective mitochondria-based clinical strategies is crucial. Today the only efficacious clinic treatment is hypothermia. However, due to its complex management, clinical complication and autoimmune decrease, its clinical application is limited. So far, many mitochondria-based strategies have been reported neuroprotective in animal models, which offers promise on neonatal therapy. However, since their clinical effectiveness are still unclear, plenty of studies need to be continued in the future. According to recent reports, two novel strategies have been proposed: methylene blue (MB) and melatonin. Although they are still in primary stage, the underlying mechanisms indicate promising clinical applications. Every neurological therapeutic strategy has its intrinsic deficit and limited efficacy, therefore in the long run, the perfect clinical therapy for hypoxic-ischemic neonatal brain injury will be based on the combination of multiple strategies. PMID:27441209

  1. [Pathology and strategies for the treatment of ischemic brain injury].

    PubMed

    Takagi, Norio

    2009-10-01

    Cerebral ischemia, a pathological condition in which brain tissue experiences a shortage or lack of glucose and oxygen, provokes an irreversible neurodegenerative disorder that may lead clinically to a progressive dementia and global cognitive deterioration. Accumulating evidence indicates many biochemical cascades that lead ultimately to ischemia-induced cell death. However, the cellular and molecular aspects of cerebral ischemia are not yet fully understood. Since the pattern of pathophysiological alterations is not the same for all cells in the ischemic brain, a good understanding of the cellular and molecular alterations induced by cerebral ischemia is needed to develop strategies for the treatment of stroke. This review summarizes recent advances concerning the pathophysiological alterations caused by cerebral ischemia, focusing on the modification of properties of glutamate receptors, which modification may be linked to the development of cerebral infarction. Furthermore, the effects of hepatocyte growth factor on learning dysfunction and cerebral vessel injury after cerebral ischemia are also summarized. Finally, this review describes a possible ameliorative effect of the injection of exogenous neural progenitor cells on cerebral ischemia-induced learning and memory dysfunction. PMID:19797876

  2. DNA damage response in renal ischemia-reperfusion and ATP-depletion injury of renal tubular cells

    PubMed Central

    Ma, Zhengwei; Wei, Qingqing; Dong, Guie; Huo, Yuqing; Dong, Zheng

    2014-01-01

    Renal ischemia-reperfusion leads to acute kidney injury (AKI) that is characterized pathologically by tubular damage and cell death, followed by tubular repair, atrophy and interstitial fibrosis. Recent work suggested the possible presence of DNA damage response (DDR) in AKI. However, the evidence is sketchy and the role and regulation of DDR in ischemic AKI remain elusive. In this study, we demonstrated the induction of phosphorylation of ATM, H2AX, Chk2 and p53 during renal ischemia-reperfusion in mice, suggesting DDR in kidney tissues. DDR was also induced in vitro during the recovery or “reperfusion” of renal proximal tubular cells (RPTCs) after ATP-depletion. DDR in RPTCs was abrogated by supplying glucose to maintain ATP via glycolysis, indicating that the DDR depends on ATP depletion. The DDR was also suppressed by the general caspase inhibitor z-VAD and the overexpression of Bcl-2, supporting a role of apoptosis-associated DNA damage in the DDR. N-acetylcysteine (NAC), an antioxidant, suppressed the phosphorylation of ATM and p53 and, to a less extent, Chk2, but NAC increased the phosphorylation and nuclear foci formation of H2AX. Interestingly, NAC increased apoptosis, which may account for the observed H2AX activation. Ku55933, an ATM inhibitor, blocked ATM phosphorylation and ameliorated the phosphorylation of Chk2 and p53, but it increased H2AX phosphorylation and nuclear foci formation. Ku55933 also increased apoptosis in RPTCs following ATP-depletion. The results suggest that DDR occurs during renal ischemia-reperfusion in vivo and ATP-depletion injury in vitro. The DDR is partially induced by apoptosis and oxidative stress-related DNA damage. ATM, as a sensor in the DDR, may play a cytoprotective role against tubular cell injury and death. PMID:24726884

  3. Renal Ischaemia Reperfusion Injury: A Mouse Model of Injury and Regeneration

    PubMed Central

    Hesketh, Emily E.; Czopek, Alicja; Clay, Michael; Borthwick, Gary; Ferenbach, David; Kluth, David; Hughes, Jeremy

    2014-01-01

    Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable during renal transplantation. Experimental models that accurately and reproducibly recapitulate renal IRI are crucial in dissecting the pathophysiology of AKI and the development of novel therapeutic agents. Presented here is a mouse model of renal IRI that results in reproducible AKI. This is achieved by a midline laparotomy approach for the surgery with one incision allowing both a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia of the left kidney. By careful monitoring of the clamp position and body temperature during the period of ischaemia this model achieves reproducible functional and structural injury. Mice sacrificed 24 hr following surgery demonstrate loss of renal function with elevation of the serum or plasma creatinine level as well as structural kidney damage with acute tubular necrosis evident. Renal function improves and the acute tissue injury resolves during the course of 7 days following renal IRI such that this model may be used to study renal regeneration. This model of renal IRI has been utilized to study the molecular and cellular pathophysiology of AKI as well as analysis of the subsequent renal regeneration. PMID:24961244

  4. Vascular endothelial growth factor: an attractive target in the treatment of hypoxic/ischemic brain injury

    PubMed Central

    Guo, Hui; Zhou, Hui; Lu, Jie; Qu, Yi; Yu, Dan; Tong, Yu

    2016-01-01

    Cerebral hypoxia or ischemia results in cell death and cerebral edema, as well as other cellular reactions such as angiogenesis and the reestablishment of functional microvasculature to promote recovery from brain injury. Vascular endothelial growth factor is expressed in the central nervous system after hypoxic/ischemic brain injury, and is involved in the process of brain repair via the regulation of angiogenesis, neurogenesis, neurite outgrowth, and cerebral edema, which all require vascular endothelial growth factor signaling. In this review, we focus on the role of the vascular endothelial growth factor signaling pathway in the response to hypoxic/ischemic brain injury, and discuss potential therapeutic interventions. PMID:26981109

  5. Vascular endothelial growth factor: an attractive target in the treatment of hypoxic/ischemic brain injury.

    PubMed

    Guo, Hui; Zhou, Hui; Lu, Jie; Qu, Yi; Yu, Dan; Tong, Yu

    2016-01-01

    Cerebral hypoxia or ischemia results in cell death and cerebral edema, as well as other cellular reactions such as angiogenesis and the reestablishment of functional microvasculature to promote recovery from brain injury. Vascular endothelial growth factor is expressed in the central nervous system after hypoxic/ischemic brain injury, and is involved in the process of brain repair via the regulation of angiogenesis, neurogenesis, neurite outgrowth, and cerebral edema, which all require vascular endothelial growth factor signaling. In this review, we focus on the role of the vascular endothelial growth factor signaling pathway in the response to hypoxic/ischemic brain injury, and discuss potential therapeutic interventions. PMID:26981109

  6. Extracellular Spermine Exacerbates Ischemic Neuronal Injury through Sensitization of ASIC1a Channels to Extracellular Acidosis

    PubMed Central

    Duan, Bo; Wang, Yi-Zhi; Yang, Tao; Chu, Xiang-Ping; Yu, Ye; Huang, Yu; Cao, Hui; Hansen, Jillian; Simon, Roger P.; Zhu, Michael X.; Xiong, Zhi-Gang; Xu, Tian-Le

    2011-01-01

    Ischemic brain injury is a major problem associated with stroke. It has been increasingly recognized that acid-sensing ion channels (ASICs) contribute significantly to ischemic neuronal damage, but the underlying mechanism has remained elusive. Here, we show that extracellular spermine, one of the endogenous polyamines, exacerbates ischemic neuronal injury through sensitization of ASIC1a channels to extracellular acidosis. Pharmacological blockade of ASIC1a or deletion of the ASIC1 gene greatly reduces the enhancing effect of spermine in ischemic neuronal damage both in cultures of dissociated neurons and in a mouse model of focal ischemia. Mechanistically, spermine profoundly reduces desensitization of ASIC1a by slowing down desensitization in the open state, shifting steady-state desensitization to more acidic pH, and accelerating recovery between repeated periods of acid stimulation. Spermine-mediated potentiation of ASIC1a activity is occluded by PcTX1 (psalmotoxin 1), a specific ASIC1a inhibitor binding to its extracellular domain. Functionally, the enhanced channel activity is accompanied by increased acid-induced neuronal membrane depolarization and cytoplasmic Ca2+ overload, which may partially explain the exacerbated neuronal damage caused by spermine. More importantly, blocking endogenous spermine synthesis significantly attenuates ischemic brain injury mediated by ASIC1a but not that by NMDA receptors. Thus, extracellular spermine contributes significantly to ischemic neuronal injury through enhancing ASIC1a activity. Our data suggest new neuroprotective strategies for stroke patients via inhibition of polyamine synthesis and subsequent spermine–ASIC interaction. PMID:21307247

  7. Acute renal injury after partial hepatectomy.

    PubMed

    Peres, Luis Alberto Batista; Bredt, Luis Cesar; Cipriani, Raphael Flavio Fachini

    2016-07-28

    Currently, partial hepatectomy is the treatment of choice for a wide variety of liver and biliary conditions. Among the possible complications of partial hepatectomy, acute kidney injury (AKI) should be considered as an important cause of increased morbidity and postoperative mortality. Difficulties in the data analysis related to postoperative AKI after liver resections are mainly due to the multiplicity of factors to be considered in the surgical patients, moreover, there is no consensus of the exact definition of AKI after liver resection in the literature, which hampers comparison and analysis of the scarce data published on the subject. Despite this multiplicity of risk factors for postoperative AKI after partial hepatectomy, there are main factors that clearly contribute to its occurrence. First factor relates to large blood losses with renal hypoperfusion during the operation, second factor relates to the occurrence of post-hepatectomy liver failure with consequent distributive circulatory changes and hepatorenal syndrome. Eventually, patients can have more than one factor contributing to post-operative AKI, and frequently these combinations of acute insults can be aggravated by sepsis or exposure to nephrotoxic drugs. PMID:27478539

  8. Acute renal injury after partial hepatectomy

    PubMed Central

    Peres, Luis Alberto Batista; Bredt, Luis Cesar; Cipriani, Raphael Flavio Fachini

    2016-01-01

    Currently, partial hepatectomy is the treatment of choice for a wide variety of liver and biliary conditions. Among the possible complications of partial hepatectomy, acute kidney injury (AKI) should be considered as an important cause of increased morbidity and postoperative mortality. Difficulties in the data analysis related to postoperative AKI after liver resections are mainly due to the multiplicity of factors to be considered in the surgical patients, moreover, there is no consensus of the exact definition of AKI after liver resection in the literature, which hampers comparison and analysis of the scarce data published on the subject. Despite this multiplicity of risk factors for postoperative AKI after partial hepatectomy, there are main factors that clearly contribute to its occurrence. First factor relates to large blood losses with renal hypoperfusion during the operation, second factor relates to the occurrence of post-hepatectomy liver failure with consequent distributive circulatory changes and hepatorenal syndrome. Eventually, patients can have more than one factor contributing to post-operative AKI, and frequently these combinations of acute insults can be aggravated by sepsis or exposure to nephrotoxic drugs. PMID:27478539

  9. Inhibition of Toll-Like Receptor 4 Signaling Mitigates Microvascular Loss but Not Fibrosis in a Model of Ischemic Acute Kidney Injury

    PubMed Central

    Dagher, Pierre C.; Hato, Takashi; Mang, Henry E.; Plotkin, Zoya; Richardson, Quentin V.; Massad, Michael; Mai, Erik; Kuehl, Sarah E.; Graham, Paige; Kumar, Rakesh; Sutton, Timothy A.

    2016-01-01

    The development of chronic kidney disease (CKD) following an episode of acute kidney injury (AKI) is an increasingly recognized clinical problem. Inhibition of toll-like receptor 4 (TLR4) protects renal function in animal models of AKI and has become a viable therapeutic strategy in AKI. However, the impact of TLR4 inhibition on the chronic sequelae of AKI is unknown. Consequently, we examined the chronic effects of TLR4 inhibition in a model of ischemic AKI. Mice with a TLR4-deletion on a C57BL/6 background and wild-type (WT) background control mice (C57BL/6) were subjected to bilateral renal artery clamping for 19 min and reperfusion for up to 6 weeks. Despite the acute protective effect of TLR4 inhibition on renal function (serum creatinine 1.6 ± 0.4 mg/dL TLR4-deletion vs. 2.8 ± 0.3 mg/dL·WT) and rates of tubular apoptosis following ischemic AKI, we found no difference in neutrophil or macrophage infiltration. Furthermore, we observed significant protection from microvascular rarefaction at six weeks following injury with TLR4-deletion, but this did not alter development of fibrosis. In conclusion, we validate the acute protective effect of TLR4 signal inhibition in AKI but demonstrate that this protective effect does not mitigate the sequential fibrogenic response in this model of ischemic AKI. PMID:27136544

  10. In situ non-ischemic enucleation of multilocular cystic renal cell carcinoma using a microwave coagulator.

    PubMed

    Kagebayashi, Y; Hirao, Y; Samma, S; Fukui, Y; Hirohashi, R

    1995-11-01

    A case of multilocular cystic renal cell carcinoma is reported, in which nephron-sparing surgery was done using microwave tissue coagulation. A 37-year-old man was referred to our outpatient clinic for a multilocular cystic tumor, 4.5 cm in diameter, in the middle-lower portion of the right kidney, which was detected by ultrasound during a health checkup. The patient had been found to have the same cystic mass on a CT done during another health checkup 1.5 years before. The tumor showed no growth during the 1.5-year period. With a diagnosis of multilocular cystic renal cell carcinoma, T2N0M0, in situ non-ischemic tumor enucleation was done using a microwave tissue coagulator (Microtaze, Heiwa Electronics Industry Inc., Tokyo). Operation time was 150 minutes and blood loss was 135 cc. The histological diagnosis was renal cell carcinoma, T2N0M0V0, cystic type, clear cell subtype, grade 1. Diagnostic imaging done postoperatively showed no sign of damage to renal function. In this report, the characteristics of multilocular cystic renal carcinoma are reviewed from the literature, and the advantages of nephron-sparing surgery for this type of renal tumor are discussed. In addition, an operative technique of tumor enucleation used in this case and the characteristics of Microtaze are introduced. PMID:8749956

  11. RGS4 inhibits angiotensin II signaling and macrophage localization during renal reperfusion injury independent of vasospasm.

    PubMed

    Pang, Paul; Jin, Xiaohua; Proctor, Brandon M; Farley, Michelle; Roy, Nilay; Chin, Matthew S; von Andrian, Ulrich H; Vollmann, Elisabeth; Perro, Mario; Hoffman, Ryan J; Chung, Joseph; Chauhan, Nikita; Mistri, Murti; Muslin, Anthony J; Bonventre, Joseph V; Siedlecki, Andrew M

    2015-04-01

    Vascular inflammation is a major contributor to the severity of acute kidney injury. In the context of vasospasm-independent reperfusion injury we studied the potential anti-inflammatory role of the Gα-related RGS protein, RGS4. Transgenic RGS4 mice were resistant to 25 min injury, although post-ischemic renal arteriolar diameter was equal to the wild type early after injury. A 10 min unilateral injury was performed to study reperfusion without vasospasm. Eighteen hours after injury, blood flow was decreased in the inner cortex of wild-type mice with preservation of tubular architecture. Angiotensin II levels in the kidneys of wild-type and transgenic mice were elevated in a sub-vasoconstrictive range 12 and 18 h after injury. Angiotensin II stimulated pre-glomerular vascular smooth muscle cells (VSMCs) to secrete the macrophage chemoattractant RANTES, a process decreased by angiotensin II R2 (AT2) inhibition. However, RANTES increased when RGS4 expression was suppressed implicating Gα protein activation in an AT2-RGS4-dependent pathway. RGS4 function, specific to VSMC, was tested in a conditional VSMC-specific RGS4 knockout showing high macrophage density by T2 MRI compared with transgenic and non-transgenic mice after the 10 min injury. Arteriolar diameter of this knockout was unchanged at successive time points after injury. Thus, RGS4 expression, specific to renal VSMC, inhibits angiotensin II-mediated cytokine signaling and macrophage recruitment during reperfusion, distinct from vasomotor regulation. PMID:25469849

  12. Upregulation of Interleukin-33 in obstructive renal injury.

    PubMed

    Chen, Wei-Yu; Chang, Ya-Jen; Su, Chia-Hao; Tsai, Tzu-Hsien; Chen, Shang-Der; Hsing, Chung-Hsi; Yang, Jenq-Lin

    2016-05-13

    Interstitial fibrosis and loss of parenchymal tubular cells are the common outcomes of progressive renal diseases. Pro-inflammatory cytokines have been known contributing to the damage of tubular cells and fibrosis responses after renal injury. Interleukin (IL)-33 is a tissue-derived nucleus alarmin that drives inflammatory responses. The regulation and function of IL-33 in renal injury, however, is not well understood. To investigate the involvement of cytokines in the pathogenesis of renal injury and fibrosis, we performed the mouse renal injury model induced by unilateral urinary obstruction (UUO) and analyze the differentially upregulated genes between the obstructed and the contralateral unobstructed kidneys using RNA sequencing (RNAseq). Our RNAseq data identified IL33 and its receptor ST2 were upregulated in the UUO kidney. Quantitative analysis confirmed that transcripts of IL33 and ST2 were upregulated in the obstructed kidneys. Immunofluorescent staining revealed that IL-33 was upregulated in Vimentin- and alpha-SMA-positive interstitial cells. By using genetically knockout mice, deletion of IL33 reduced UUO-induced renal fibrosis. Moreover, in combination with BrdU labeling technique, we observed that the numbers of proliferating tubular epithelial cells were increased in the UUO kidneys from IL33-or ST2-deficient mice compared to wild type mice. Collectively, our study demonstrated the upregulation of IL-33/ST2 signaling in the obstructed kidney may promote tubular cell injury and interstitial fibrosis. IL-33 may serve as a biomarker to detect renal injury and that IL-33/ST2 signaling may represent a novel target for treating renal diseases. PMID:27067050

  13. Metaplastic and mitotic activity of the ischemic (endocrine) kidney in experimental renal hypertension.

    PubMed Central

    Cantin, M.; Solymoss, B.; Benchimol, S.; Desormeaux, Y.; Langlais, J.; Ballak, M.

    1979-01-01

    Partial ligation of the aorta between the renal arteries in the rat induces malignant hypertension, metaplasia of smooth-muscle cells of arterioles and arteries into juxtaglomerular cells, and a complex series of events in tubular cells at all levels of the ischemic kidney. The tubular cells of the outer cortex, particularly the proximal convoluted cells, show a very rapid and progressive simple atrophy. In contrast, necrosis of individual cells is followed by mitotic activity in atrophic tubular cells of the inner cortex, medulla, and papilla. Subsequently, polyploidy and hyperplasia occur in the inner cortex. At the same time, hypertrophy of the protein-synthesizing apparatus and an increase in protein, DNA, and RNA, followed by a decrease in the protein content, are seen in the tubular cells of the inner cortex. In the medulla and papilla, necrosis of individual cells proceeds side by side with waves of mitotic activity. These events take place, albeit to a lesser degree, even in cases of very mild renal ischemia. While they may by unrelated to hypertension, these changes are probably involved in the increase in hydrolytic enzyme activity characteristic of the ischemic renal cortex. Images Figure 3 Figure 4 Figure 9 Figure 10 Figure 7 Figure 8 Figure 1 Figure 2 Figure 5 Figure 6 PMID:474709

  14. Increased myocardial ischemia-reperfusion injury in renal failure involves cardiac adiponectin signal deficiency.

    PubMed

    Song, Yanbin; Yu, Qiujun; Zhang, Junyi; Huang, Weidong; Liu, Yi; Pei, Haifeng; Liu, Jingyi; Sun, Lu; Yang, Lu; Li, Congye; Li, Yan; Zhang, Fuyang; Qu, Yan; Tao, Ling

    2014-05-01

    Plasma levels of adiponectin (APN) are significantly increased in patients with renal dysfunction and are inversely related to the risk of cardiovascular mortality. The present study was designed to determine the role of APN in myocardial ischemia-reperfusion (MI/R) injury in mice with renal failure and delineate the underlying mechanisms. Renal failure was induced by subtotal nephrectomy (SN). Human recombinant globular domain of adiponectin (gAd) or full-length adiponectin (fAd) was administered via intraperitoneal injection once daily for 7 consecutive days after SN, and in vivo MI/R was introduced 3 wk later. Both plasma and urinary levels of APN increased significantly in SN mice. Compared with sham-operated mice, cardiac function was significantly depressed, and myocardial infarct size and apoptosis increased in SN mice following MI/R. The aggravated MI/R injury was further intensified in APN-knockout mice and markedly ameliorated by treatment with gAd but not fAd. Moreover, SN increased myocardial NO metabolites, superoxide, and their cytotoxic reaction product peroxynitrite, upregulated inducible NO synthase expression, and decreased endothelial NOS phosphorylation. In addition, SN mice also exhibited reduced APN receptor-1 (AdipoR1) expression and AMPK activation. All these changes were further amplified in the absence of APN but reversed by gAd treatment. The present study demonstrates that renal dysfunction increases cardiac susceptibility to ischemic-reperfusion injury, which is associated with downregulated APN/AdipoR1/AMPK signaling and increased oxidative/nitrative stress in local myocardium, and provides the first evidence for the protective role of exogenous supplement of gAd on MI/R outcomes in renal failure. PMID:24595307

  15. Acute Stress Decreases but Chronic Stress Increases Myocardial Sensitivity to Ischemic Injury in Rodents

    PubMed Central

    Eisenmann, Eric D.; Rorabaugh, Boyd R.; Zoladz, Phillip R.

    2016-01-01

    Cardiovascular disease (CVD) is the largest cause of mortality worldwide, and stress is a significant contributor to the development of CVD. The relationship between acute and chronic stress and CVD is well evidenced. Acute stress can lead to arrhythmias and ischemic injury. However, recent evidence in rodent models suggests that acute stress can decrease sensitivity to myocardial ischemia–reperfusion injury (IRI). Conversely, chronic stress is arrhythmogenic and increases sensitivity to myocardial IRI. Few studies have examined the impact of validated animal models of stress-related psychological disorders on the ischemic heart. This review examines the work that has been completed using rat models to study the effects of stress on myocardial sensitivity to ischemic injury. Utilization of animal models of stress-related psychological disorders is critical in the prevention and treatment of cardiovascular disorders in patients experiencing stress-related psychiatric conditions. PMID:27199778

  16. Acute Stress Decreases but Chronic Stress Increases Myocardial Sensitivity to Ischemic Injury in Rodents.

    PubMed

    Eisenmann, Eric D; Rorabaugh, Boyd R; Zoladz, Phillip R

    2016-01-01

    Cardiovascular disease (CVD) is the largest cause of mortality worldwide, and stress is a significant contributor to the development of CVD. The relationship between acute and chronic stress and CVD is well evidenced. Acute stress can lead to arrhythmias and ischemic injury. However, recent evidence in rodent models suggests that acute stress can decrease sensitivity to myocardial ischemia-reperfusion injury (IRI). Conversely, chronic stress is arrhythmogenic and increases sensitivity to myocardial IRI. Few studies have examined the impact of validated animal models of stress-related psychological disorders on the ischemic heart. This review examines the work that has been completed using rat models to study the effects of stress on myocardial sensitivity to ischemic injury. Utilization of animal models of stress-related psychological disorders is critical in the prevention and treatment of cardiovascular disorders in patients experiencing stress-related psychiatric conditions. PMID:27199778

  17. Loss of activator of G-protein signaling 3 impairs renal tubular regeneration following acute kidney injury in rodents

    PubMed Central

    Regner, Kevin R.; Nozu, Kandai; Lanier, Stephen M.; Blumer, Joe B.; Avner, Ellis D.; Sweeney, William E.; Park, Frank

    2011-01-01

    The intracellular mechanisms underlying renal tubular epithelial cell proliferation and tubular repair following ischemia-reperfusion injury (IRI) remain poorly understood. In this report, we demonstrate that activator of G-protein signaling 3 (AGS3), an unconventional receptor-independent regulator of heterotrimeric G-protein function, influences renal tubular regeneration following IRI. In rat kidneys exposed to IRI, there was a temporal induction in renal AGS3 protein expression that peaked 72 h after reperfusion and corresponded to the repair and recovery phase following ischemic injury. Renal AGS3 expression was localized predominantly to the recovering outer medullary proximal tubular cells and was highly coexpressed with Ki-67, a marker of cell proliferation. Kidneys from mice deficient in the expression of AGS3 exhibited impaired renal tubular recovery 7 d following IRI compared to wild-type AGS3-expressing mice. Mechanistically, genetic knockdown of endogenous AGS3 mRNA and protein in renal tubular epithelial cells reduced cell proliferation in vitro. Similar reductions in renal tubular epithelial cell proliferation were observed following incubation with gallein, a selective inhibitor of Gβγ subunit activity, and lentiviral overexpression of the carboxyl-terminus of G-protein-coupled receptor kinase 2 (GRK2ct), a scavenger of Gβγ subunits. In summary, these data suggest that AGS3 acts through a novel receptor-independent mechanism to facilitate renal tubular epithelial cell proliferation and renal tubular regeneration.—Regner, K. R., Nozu, K., Lanier, S. M., Blumer, J. B., Avner, E. D., Sweeney, Jr., W. E., Park, F. Loss of activator of G-protein signaling 3 impairs renal tubular regeneration following acute kidney injury in rodents. PMID:21343176

  18. Dapagliflozin, SGLT2 Inhibitor, Attenuates Renal Ischemia-Reperfusion Injury

    PubMed Central

    Chang, Yoon-Kyung; Choi, Hyunsu; Jeong, Jin Young; Na, Ki-Ryang; Lee, Kang Wook

    2016-01-01

    Dapagliflozin, a new type of drug used to treat diabetes mellitus (DM), is a sodium/glucose cotransporter 2 (SGLT2) inhibitor. Although some studies showed that SGLT2 inhibition attenuated reactive oxygen generation in diabetic kidney the role of SGLT2 inhibition is unknown. We evaluated whether SLT2 inhibition has renoprotective effects in ischemia-reperfusion (IR) models. We evaluated whether dapagliflozin reduces renal damage in IR mice model. In addition, hypoxic HK2 cells were treated with or without SGLT2 inhibitor to investigate cell survival, the apoptosis signal pathway, and the induction of hypoxia-inducible factor 1 (HIF1) and associated proteins. Dapagliflozin improved renal function. Dapagliflozin reduced renal expression of Bax, renal tubule injury and TUNEL-positive cells and increased renal expression of HIF1 in IR-injured mice. HIF1 inhibition by albendazole negated the renoprotective effects of dapagliflozin treatment in IR-injured mice. In vitro, dapagliflozin increased the expression of HIF1, AMP-activated protein kinase (AMPK), and ERK and increased cell survival of hypoxic HK2 cells in a dose-dependent manner. In conclusion, dapagliflozin attenuates renal IR injury. HIF1 induction by dapagliflozin may play a role in renoprotection against renal IR injury. PMID:27391020

  19. Renal injury, nephrolithiasis and Nigella sativa: A mini review

    PubMed Central

    Hayatdavoudi, Parichehr; Khajavi Rad, Abolfazl; Rajaei, Ziba; Hadjzadeh, Mousa AL-Reza

    2016-01-01

    Objective: The incidence and prevalence of kidney stone is increasing worldwide. After the first recurrence the risk of subsequent relapses is higher and the time period between relapses is shortened. Urinary stones can be severely painful and make a huge economic burden. The stone disease may increase the vulnerability of patients to other diseases such as renal failure. Medicinal herbs are rich sources of antioxidants which are increasingly consumed globally for their safety, efficacy and low price. Nigella sativa is a spice plant that is widely used for prevention and treatment of many ailments in Muslim countries and worldwide. This review aims at investigation of the effects of Nigella sativa on renal injury and stone formation. Materials and Methods: The scientific resources including PubMed, Scopus, and Google scholar were searched using key words such as: nephrolithiasis, urolithiasis, kidney/renal stone, renal injury, renal failure, urinary retention and black seed, black cumin, Nigella sativa and thymoquinone. Results: N. sativa and its main component, thymoquinone showed positive effects in prevention or curing kidney stones and renal failure through various mechanism such as antioxidative, anti-inflammatory, anti-eicosanoid and immunomodulatory effects. The putative candidate in many cases has been claimed to be thymoquinone but it seems that at least in part, particularly in kidney stones, the herbal melanin plays a role which requires further investigation to prove. Conclusion: N. sativa and its components are beneficial in prevention and curing of renal diseases including nephrolithiasis and renal damages. PMID:27247917

  20. Therapeutic Hypothermia as a Neuroprotective Strategy in Neonatal Hypoxic-Ischemic Brain Injury and Traumatic Brain Injury

    PubMed Central

    Ma, H.; Sinha, B.; Pandya, R.S.; Lin, N.; Popp, A.J.; Li, J.; Yao, J.; Wang, X.

    2014-01-01

    Evidence shows that artificially lowering body and brain temperature can significantly reduce the deleterious effects of brain injury in both newborns and adults. Although the benefits of therapeutic hypothermia have long been known and applied clinically, the underlying molecular mechanisms have yet to be elucidated. Hypoxic-ischemic brain injury and traumatic brain injury both trigger a series of biochemical and molecular events that cause additional brain insult. Induction of therapeutic hypothermia seems to ameliorate the molecular cascade that culminates in neuronal damage. Hypothermia attenuates the toxicity produced by the initial injury that would normally produce reactive oxygen species, neurotransmitters, inflammatory mediators, and apoptosis. Experiments have been performed on various depths and levels of hypothermia to explore neuroprotection. This review summarizes what is currently known about the beneficial effects of therapeutic hypothermia in experimental models of neonatal hypoxic-ischemic brain injury and traumatic brain injury, and explores the molecular mechanisms that could become the targets of novel therapies. In addition, this review summarizes the clinical implications of therapeutic hypothermia in newborn hypoxic-ischemic encephalopathy and adult traumatic brain injury. PMID:22834830

  1. 99mTc-MAG3 scintigraphy for the longitudinal follow-up of kidney function in a mouse model of renal ischemia-reperfusion injury

    PubMed Central

    2012-01-01

    Background Experimental models are essential tools in the development and evaluation of novel treatment options, but the preclinical model of renal ischemia-reperfusion injury is limited to the retrieval of (very) early functional data, leaving the pivotal long-term outcome unknown. The present study applies technetium-99m-mercapto-acetyl-tri-glycine [99mTc-MAG3] scintigraphy for the longitudinal follow-up examination of long-term kidney function after renal ischemia-reperfusion injury. Methods Unilateral warm ischemia was induced in scid beige mice by vascular clamping of the kidney hilum for 40 min. 99mTc-MAG3 scintigraphy was performed prior to injury, 8 and 14 days post ischemia. The fractional uptake rate [FUR] was calculated from scintigraphy data as a measure of renal clearance. Results FUR demonstrated a significant functional impairment of the ischemic kidney 8 and 14 days after injury (P < 0.05 vs. baseline), while contralateral non-ischemic kidneys showed no significant changes. In histological analysis, ischemic kidneys exhibited tubular dilatation and cytoplasmic degeneration as signs of hypoxia without any evidence for necrosis. Conclusions FUR enables the detection of renal dysfunction and longitudinal long-term follow-up examination in the same individual. Our model may facilitate preclinical therapy evaluation for the identification of effective renoprotective therapies. PMID:22264389

  2. Renal functional reserve and renal recovery after acute kidney injury.

    PubMed

    Sharma, Aashish; Mucino, Marìa Jimena; Ronco, Claudio

    2014-01-01

    Renal functional reserve (RFR) represents the capacity of the kidney to increase glomerular filtration rate (GFR) in response to certain physiological or pathological stimuli or conditions. Once baseline GFR is determined, RFR can be assessed clinically after an oral protein load or intravenous amino acid infusion. In clinical practice, baseline GFR displays variable levels due to diet or other factors. RFR is the difference between peak 'stress' GFR induced by the test (p.o. or i.v.) and the baseline GFR. In clinical scenarios where hyperfiltration is present (high baseline GFR due to pregnancy, hypertension or diabetic nephropathy, in solitary kidney or kidney donors), RFR may be fully or partially used to achieve normal or supranormal renal function. Since commonly used renal function markers, such as GFR, may remain within normal ranges until 50% of nephrons are lost or in patients with a single remnant kidney, the RFR test may represent a sensitive and early way to assess the functional decline in the kidney. RFR assessment may become an important tool to evaluate the ability of the kidney to recover completely or partially after a kidney attack. In case of healing with a defect and progressive fibrosis, recovery may appear complete clinically, but a reduced RFR may be a sign of a maladaptive repair or subclinical loss of renal mass. Thus, a reduction in RFR may represent the equivalent of renal frailty or susceptibility to insults. The main aim of this article is to review the concept of RFR, its utility in different clinical scenarios, and future perspective for its use. PMID:25343829

  3. Erythropoietin-enhanced endothelial progenitor cell recruitment in peripheral blood and renal vessels during experimental acute kidney injury in rats.

    PubMed

    Cakiroglu, Figen; Enders-Comberg, Sora Maria; Pagel, Horst; Rohwedel, Jürgen; Lehnert, Hendrik; Kramer, Jan

    2016-03-01

    Beneficial effects of erythropoietin (EPO) have been reported in acute kidney injury (AKI) when administered prior to induction of AKI. We studied the effects of EPO administration on renal function shortly after ischemic AKI. For this purpose, rats were subjected to renal ischemia for 30 min and EPO was administered at a concentration of 500 U/kg either i.v. as a single shot directly after ischemia or with an additional i.p. dose until 3 days after surgery. The results were compared with AKI rats without EPO application and a sham-operated group. Renal function was assessed by measurement of serum biochemical markers, histological grading, and using an isolated perfused kidney (IPK) model. Furthermore, we performed flow cytometry to analyze the concentration of endothelial progenitor cells (EPCs) in the peripheral blood and renal vessels. Following EPO application, there was only a statistically non-significant tendency of serum creatinine and urea to improve, particularly after daily EPO application. Renal vascular resistance and the renal perfusion rate were not significantly altered. In the histological analysis, acute tubular necrosis was only marginally ameliorated following EPO administration. In summary, we could not demonstrate a significant improvement in renal function when EPO was applied after AKI. Interestingly, however, EPO treatment resulted in a highly significant increase in CD133- and CD34-positive EPC both in the peripheral blood and renal vessels. PMID:26616141

  4. The Use of Hypothermia Therapy in Traumatic Ischemic/Reperfusional Brain Injury: Review of the Literatures

    PubMed Central

    Frantzen, Janek; Bullock, Ross; Gajavelli, Shyam; Burks, Stephen; Bramlett, Helen; Dietrich, W. Dalton

    2011-01-01

    Therapeutic mild hypothermia has been widely used in brain injury. It has been evaluated in numerous clinical trials, and there is strong evidence for the use of hypothermia in treating patients with several types of ischemic/reperfusional (I/R) injuries, the examples being cardiac arrest and neonatal hypoxic-ischemic encephalopathy. In spite of many basic research projects demonstrating effectiveness, therapeutic hypothermia has not been proved effective for the heterogeneous group of patients with traumatic brain injury (TBI) in multicenter clinical trials. In the latest clinical trial, however, researchers were able to demonstrate the significant beneficial effects of hypothermia in one specific group; patients with mass evacuated lesions. This suggested that mild therapeutic hypothermia might be effective for I/R related TBI. In this article, we have reviewed much of the previous literature concerning the mechanisms of I/R injury to the protective effects of mild therapeutic hypothermia. PMID:23439678

  5. Advance in spinal cord ischemia reperfusion injury: Blood-spinal cord barrier and remote ischemic preconditioning.

    PubMed

    Yu, Qijing; Huang, Jinxiu; Hu, Ji; Zhu, Hongfei

    2016-06-01

    The blood-spinal cord barrier (BSCB) is the physiological and metabolic substance diffusion barrier between blood circulation and spinal cord tissues. This barrier plays a vital role in maintaining the microenvironment stability of the spinal cord. When the spinal cord is subjected to ischemia/reperfusion (I/R) injury, the structure and function of the BSCB is disrupted, further destroying the spinal cord homeostasis and ultimately leading to neurological deficit. Remote ischemic preconditioning (RIPC) is an approach in which interspersed cycles of preconditioning ischemia is followed by reperfusion to tissues/organs to protect the distant target tissues/organs against subsequent lethal ischemic injuries. RIPC is an innovation of the treatment strategies that protect the organ from I/R injury. In this study, we review the morphological structure and function of the BSCB, the injury mechanism of BSCB resulting from spinal cord I/R, and the effect of RIPC on it. PMID:27060223

  6. Lumican overexpression exacerbates lipopolysaccharide-induced renal injury in mice.

    PubMed

    Lu, Xiao-Mei; Ma, Ling; Jin, Yu-Nan; Yu, Yan-Qiu

    2015-09-01

    The present study aimed to investigate the role of lumican in mice with endotoxin-induced acute renal failure (ARF). Lumican transgenic mice and wild‑type mice were injected with lipopolysaccharide (LPS; 10 mg/kg) to establish a model of ARF. The mice were sacrificed at 24 h and the blood and renal tissue samples were collected. The value of serum creatinine (SCr) and blood urea nitrogen (BUN) were measured to determine renal function. An ELISA was used to determined the concentrations of renal cytokines, including tumor necrosis factor (TNF)α, interleukin (IL)‑6, IL‑4 and IL‑10. The protein expression levels of Toll-like receptor (TLR4) and nuclear factor (NF)κB in renal tissues were assessed using western blot analysis. Terminal deoxynucleotidyl transferase‑mediated dUTP nick end labeling was performed to monitor apoptosis of renal tissue. Light microscopy and electron microscopy were used to observe structural changes in the renal tissues. Following the administration of LPS, the SCr and BUN values of mice in the lumican transgenic group were higher compared with those in the control group. The expression levels of renal TLR4, NFκB, TNFα, IL‑6, IL‑4 and IL‑10 were upregulated in the lumican transgenic mice compared with those in the wild‑type control group. Apoptosis was detected predominantly on the renal tubule. There was a significant difference in the optical density of apoptotic bodies between the control mice and the lumican transgenic mice. Light and electron microscopy demonstrated more severe renal tissue injury in the lumican transgenic mice compared with that in the control mice. In conclusion, LPS may cause excessive apoptosis in the renal tubular cells via the TLR4 signal transduction pathway, a decrease in the number of renal tubular cells and ARF. Lumican may be important in mice with LPS-induced ARF. PMID:26081832

  7. Radon inhalation protects against transient global cerebral ischemic injury in gerbils.

    PubMed

    Kataoka, Takahiro; Etani, Reo; Takata, Yuji; Nishiyama, Yuichi; Kawabe, Atsushi; Kumashiro, Masayuki; Taguchi, Takehito; Yamaoka, Kiyonori

    2014-10-01

    Although brain disorders are not the main indication for radon therapy, our previous study suggested that radon inhalation therapy might mitigate brain disorders. In this study, we assessed whether radon inhalation protects against transient global cerebral ischemic injury in gerbils. Gerbils were treated with inhaled radon at a concentration of 2,000 Bq/m(3) for 24 h. After radon inhalation, transient global cerebral ischemia was induced by bilateral occlusion of the common carotid artery. Results showed that transient global cerebral ischemia induced neuronal damage in hippocampal CA1, and the number of damaged neurons was significantly increased compared with control. However, radon treatment inhibited ischemic damage. Superoxide dismutase (SOD) activity in the radon-treated gerbil brain was significantly higher than that in sham-operated gerbils. These findings suggested that radon inhalation activates antioxidative function, especially SOD, thereby inhibiting transient global cerebral ischemic injury in gerbils. PMID:24792782

  8. The Synthetic Tie2 Agonist Peptide Vasculotide Protects Renal Vascular Barrier Function In Experimental Acute Kidney Injury

    PubMed Central

    Rübig, Eva; Stypmann, Jörg; Van Slyke, Paul; Dumont, Daniel J; Spieker, Tilmann; Buscher, Konrad; Reuter, Stefan; Goerge, Tobias; Pavenstädt, Hermann; Kümpers, Philipp

    2016-01-01

    Microvascular barrier dysfunction plays a major role in the pathophysiology of acute kidney injury (AKI). Angiopoietin-1, the natural agonist ligand for the endothelial-specific Tie2 receptor, is a non-redundant endothelial survival and vascular stabilization factor. Here we evaluate the efficacy of a polyethylene glycol-clustered Tie2 agonist peptide, vasculotide (VT), to protect against endothelial-cell activation with subsequent microvascular dysfunction in a murine model of ischemic AKI. Renal ischemia reperfusion injury (IRI) was induced by clamping of the renal arteries for 35 minutes. Mice were treated with VT or PEGylated cysteine before IRI. Sham-operated animals served as time-matched controls. Treatment with VT significantly reduced transcapillary albumin flux and renal tissue edema after IRI. The protective effects of VT were associated with activation of Tie2 and stabilization of its downstream effector, VE-cadherin in renal vasculature. VT abolished the decline in renal tissue blood flow, attenuated the increase of serum creatinine and blood urea nitrogen after IRI, improved recovery of renal function and markedly reduced mortality compared to PEG [HR 0.14 (95% CI 0.05–0.78) P < 0.05]. VT is inexpensive to produce, chemically stable and unrelated to any Tie2 ligands. Thus, VT may represent a novel therapy to prevent AKI in patients. PMID:26911791

  9. Radiofrequency Renal Denervation Protects the Ischemic Heart via Inhibition of GRK2 and Increased Nitric Oxide Signaling

    PubMed Central

    Polhemus, David J.; Gao, Juan; Scarborough, Amy L.; Trivedi, Rishi; McDonough, Kathleen H.; Goodchild, Traci T.; Smart, Frank

    2016-01-01

    Rationale: Catheter-based renal denervation (RDN) is currently under development for the treatment of resistant hypertension and is thought to reduce blood pressure via interruption of sympathetic pathways that modulate cardiovascular function. The sympathetic nervous system also plays a critical role in the pathogenesis of acute myocardial infarction and heart failure. Objective: We examined whether treatment with radiofrequency (RF)-RDN would protect the heart against subsequent myocardial ischemia/reperfusion injury via direct effects on the myocardium. Methods and Results: Spontaneously hypertensive rats received either bilateral RF-RDN or sham-RDN. At 4 weeks after RF-RDN (n=14) or sham-RDN (n=14) treatment, spontaneously hypertensive rats were subjected to 30 minutes of transient coronary artery occlusion and 24 hours –7 days reperfusion. Four weeks after RF-RDN, myocardial oxidative stress was markedly attenuated, and transcription and translation of antioxidants, superoxide dismutase 1 and glutathione peroxidase-1, were significantly upregulated compared with sham-RDN spontaneously hypertensive rats. RF-RDN also inhibited myocardial G protein–coupled receptor kinase 2 pathological signaling and enhanced myocardial endothelial nitric oxide synthase function and nitric oxide signaling. RF-RDN therapy resulted in a significant reduction in myocardial infarct size per area at risk compared with sham-RDN (26.8 versus 43.9%; P<0.01) at 24 hours postreperfusion and significantly improved left ventricular function at 7 days after myocardial ischemia/reperfusion. Conclusions: RF-RDN reduced oxidative stress, inhibited G protein–coupled receptor kinase 2 signaling, increased nitric oxide bioavailability, and ameliorated myocardial reperfusion injury in the setting of severe hypertension. These findings provide new insights into the remote cardioprotective effects of RF-RDN acting directly on cardiac myocytes to attenuate cell death and protect against ischemic

  10. The role of autophagic and lysosomal pathways in ischemic brain injury

    PubMed Central

    Gu, Zhaohua; Sun, Yinyi; Liu, Kangyong; Wang, Fen; Zhang, Ting; Li, Qiang; Shen, Liwei; Zhou, Ling; Dong, Liang; Shi, Nan; Zhang, Qian; Zhang, Wei; Zhao, Meizhen; Sun, Xiaojiang

    2013-01-01

    Autophagy is involved in neural cell death after cerebral ischemia. Our previous studies showed that rapamycin-induced autophagy decreased the rate of apoptosis, but the rate of apoptosis was creased after the autophagy inhibitor, 3-methyladenine, was used. In this study, a suture-occluded method was performed to generate a rat model of brain ischemia. Under a transmission electron microscope, autophagic bodies and autophagy lysosomes were markedly accumulated in neurons at 4 hours post brain ischemic injury, with their numbers gradually reducing over time. Western blotting demonstrated that protein levels of light chain 3-II and cathepsin B were significantly increased within 4 hours of ischemic injury, but these levels were not persistently upregulated over time. Confocal microscopy showed that autophagy was mainly found in neurons with positive light chain 3 signal. Injection of rapamycin via tail vein promoted the occurrence of autophagy in rat brain tissue after cerebral ischemia and elevated light chain 3 and cathepsin B expression. However, injection of 3-methyladenine significantly diminished light chain 3-II and cathepsin B expression. Results verified that autophagic and lysosomal activity is increased in ischemic neurons. Abnormal components in cells can be eliminated through upregulating cell autophagy or inhibiting autophagy after ischemic brain injury, resulting in a dynamic balance of substances in cells. Moreover, drugs that interfere with autophagy may be potential therapies for the treatment of brain injury. PMID:25206520

  11. Acute effects of all-trans-retinoic acid in ischemic injury

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All-trans-retinoic acid (ATRA) is a vitamin A derivative that is important in neuronal patterning, survival, and neurite outgrowth. We investigated the relatively acute effects of ATRA (100 nM and 1 µM) on cell swelling in ischemic injury and on key features hypothesized to contribute to cell swelli...

  12. Automated Detection of Brain Abnormalities in Neonatal Hypoxia Ischemic Injury from MR Images

    PubMed Central

    Ghosh, Nirmalya; Sun, Yu; Bhanu, Bir; Ashwal, Stephen; Obenaus, Andre

    2014-01-01

    We compared the efficacy of three automated brain injury detection methods, namely symmetry-integrated region growing (SIRG), hierarchical region splitting (HRS) and modified watershed segmentation (MWS) in human and animal magnetic resonance imaging (MRI) datasets for the detection of hypoxic ischemic injuries (HII). Diffusion weighted imaging (DWI, 1.5T) data from neonatal arterial ischemic stroke (AIS) patients, as well as T2-weighted imaging (T2WI, 11.7T, 4.7T) at seven different time-points (1, 4, 7, 10, 17, 24 and 31 days post HII) in rat-pup model of hypoxic ischemic injury were used to check the temporal efficacy of our computational approaches. Sensitivity, specificity, similarity were used as performance metrics based on manual (‘gold standard’) injury detection to quantify comparisons. When compared to the manual gold standard, automated injury location results from SIRG performed the best in 62% of the data, while 29% for HRS and 9% for MWS. Injury severity detection revealed that SIRG performed the best in 67% cases while HRS for 33% data. Prior information is required by HRS and MWS, but not by SIRG. However, SIRG is sensitive to parameter-tuning, while HRS and MWS are not. Among these methods, SIRG performs the best in detecting lesion volumes; HRS is the most robust, while MWS lags behind in both respects. PMID:25000294

  13. Detection of renal brush border membrane enzymes for evaluation of renal injury in neonatal scleredema

    PubMed Central

    Ren, Qing; Zhang, Yongjun; Yang, Jinying; Wei, Lixia; Zhao, Lili; Yang, Qiaozhi

    2015-01-01

    Objective: To evaluate renal brush border membrane enzymes in urine as an indicator for renal injury in neonatal scleredema (NS). Methods: Sixty nine NS patients in our hospital were enrolled and divided into mild group and moderate/severe group. Patients were further randomly divided into therapy and control subgroups for 7 days ligustrazine administration. Urine samples were collected to detect renal brush border membrane enzymes (RBBME) by ELISA and β2-microglobulin (β2-MG) by radioimmunoassay (RIA). The results were compared with those of 30 normal neonates. Data were statistically analyzed using SPSS13.0 software. Results: Both RBBME and β2-MG were found to be higher in urine in NS patients than normal controls (P < 0.01). Level of RBBME increased with the severity of NS (P <0.05), while urinary β2-MG did not (P >0.05). After being treated with ligustrazine, a medicine for renal function recovery, both RBBME and β2-MG were similarly significantly decreased comparing to untreated groups (P < 0.05). 79.7% of NS patients showed abnormal RBBME while only 52.2% had an abnormal urinary β2-MG (χ2=11.65,P < 0.01). Conclusion: RBBME was more sensitive than β2-MG in reflecting the renal injury in NS. Examination of RBBME effectively reflected the recovery of renal injury after treatment with ligustrazine. PMID:25878616

  14. Experiences of Conflict Zone-Related Ballistic Renal Injury.

    PubMed

    Taş, Huseyin; Şenocak, Rahman; Kaymak, Şahin; Lapsekili, Emin

    2016-08-01

    To analyze our approaches and experiences in patients with renal injuries accompanying penetrating abdominal injuries admitted to the hospital due to high kinetic energy weapons. Patients including renal injuries associated with penetrating abdominal injuries due to gunshot wounds and fragments of shell treated at our institution between February 2002 and May 2013 were retrospectively analyzed. Total 21 patients were included in this study, 20 of whom (86.2 %) were male and 1 (13.8 %) female. Renal injury was scaled in 2 patients as grade 1, 4 patients as grade 2, 4 patients as grade 3, 8 patients as grade 4, and 3 patients as grade 5. While conservative treatment was applied to patients with grade 1 and 2 injuries, 2 patients with grade 3 injury underwent renal repair and the other 13 patients underwent nephrectomy. The amount of blood transfused in all cases was determined to be mean 8.28 (6-16) units for red blood cells (ES) and 9 (6-17) units for fresh frozen plasma. When patients were assessed according to the Penetrating Abdominal Trauma Index (PATI) scores, the median score and average PATI score were 35 and 37.6 (10-70), respectively. A physical examination along with a quick assessment of vital signs should be made, and unnecessary and time-consuming investigations such as abdominal tomography and angiographic intervention should be avoided. Conservative and organ preservation should be considered absolutely for appropriately selected patients, namely in stable patients in whom kinetic energy transfer is less and who have bullet path away from midline. However, the majority of these patients are considered to be hemodynamically unstable condition, possible complications of the procedure to be applied, and selection of patients should be carefully evaluated. PMID:27574348

  15. Myocardial ischemic post-conditioning attenuates ischemia reperfusion injury via PTEN/Akt signal pathway

    PubMed Central

    Li, Chun-Mei; Shen, Shu-Wen; Wang, Tao; Zhang, Xing-Hua

    2015-01-01

    Objectives: To investigate whether myocardial ischemic post-conditioning attenuates ischemia reperfusion injury via PTEN/Akt signal pathway. Design: Forty-five male Sprague-Dawley rats were randomly divided into three groups: Sham, Ischemia reperfusion (I/R) and Ischemic post-conditioning (IPost) group. After the experiment finished, myocardial infarction area was examined. Serum creatine phosphokinase and lactate dehydrogenase activity were detected at baseline and the end of reperfusion. The protein levels of PTEN, Akt, p-Akt, Bax and Bcl-2 were measured by Western blot method. Results: Myocardial infarct size was significantly reduced in IPost as compared to I/R. Results were confirmed by serum creatine phosphokinase and lactate dehydrogenase activity. In addition, PTEN and Bax protein expression were inhibited and the p-Akt and bcl-2 protein expression were enhanced in IPost compared with I/R (P < 0.05). At the same time, the ratio of Bax and Bcl-2 was decreased in IPost (P < 0.05). However, ischemic post conditioning did not affect the total Akt level (P > 0.05). Conclusions: We confirmed that ischemic post-conditioning protects the heart against reperfusion injury. It is important that we demonstrated that the cardioprotective effect of ischemic post-conditioning was involved in the inhibition of PTEN, activation of the PI3K/Akt pathway and reduction of the cardiomyocyte apoptosis. PMID:26629079

  16. Unilateral Renal Ischemia-Reperfusion as a Robust Model for Acute to Chronic Kidney Injury in Mice.

    PubMed

    Le Clef, Nathalie; Verhulst, Anja; D'Haese, Patrick C; Vervaet, Benjamin A

    2016-01-01

    Acute kidney injury (AKI) is an underestimated, yet important risk factor for development of chronic kidney disease (CKD). Even after initial total recovery of renal function, some patients develop progressive and persistent deterioration of renal function and these patients are more likely to progress to end-stage renal disease (ESRD). Animal models are indispensable for unravelling the mechanisms underlying this progression towards CKD and ESRD and for the development of new therapeutic strategies in its prevention or treatment. Ischemia (i.e. hypoperfusion after surgery, bleeding, dehydration, shock, or sepsis) is a major aetiology in human AKI, yet unilateral ischemia-reperfusion is a rarely used animal model for research on CKD and fibrosis. Here, we demonstrate in C57Bl/6J mice, by both histology and gene expression, that unilateral ischemia-reperfusion without contralateral nephrectomy is a very robust model to study the progression from acute renal injury to long-term tubulo-interstitial fibrosis, i.e. the histopathological hallmark of CKD. Furthermore, we report that the extent of renal fibrosis, in terms of Col I, TGFβ, CCN2 and CCN3 expression and collagen I immunostaining, increases with increasing body temperature during ischemia and ischemia-time. Thus, varying these two main determinants of ischemic injury allows tuning the extent of the long-term fibrotic outcome in this model. Finally, in order to cover the whole practical finesse of ischemia-reperfusion and allow model and data transfer, we provide a referenced overview on crucial technical issues (incl. anaesthesia, analgesia, and pre- and post-operative care) with the specific aim of putting starters in the right direction of implementing ischemia in their research and stimulate them, as well as the community, to have a critical view on ischemic literature data. PMID:27007127

  17. Unilateral Renal Ischemia-Reperfusion as a Robust Model for Acute to Chronic Kidney Injury in Mice

    PubMed Central

    Le Clef, Nathalie; Verhulst, Anja; D’Haese, Patrick C.; Vervaet, Benjamin A.

    2016-01-01

    Acute kidney injury (AKI) is an underestimated, yet important risk factor for development of chronic kidney disease (CKD). Even after initial total recovery of renal function, some patients develop progressive and persistent deterioration of renal function and these patients are more likely to progress to end-stage renal disease (ESRD). Animal models are indispensable for unravelling the mechanisms underlying this progression towards CKD and ESRD and for the development of new therapeutic strategies in its prevention or treatment. Ischemia (i.e. hypoperfusion after surgery, bleeding, dehydration, shock, or sepsis) is a major aetiology in human AKI, yet unilateral ischemia-reperfusion is a rarely used animal model for research on CKD and fibrosis. Here, we demonstrate in C57Bl/6J mice, by both histology and gene expression, that unilateral ischemia-reperfusion without contralateral nephrectomy is a very robust model to study the progression from acute renal injury to long-term tubulo-interstitial fibrosis, i.e. the histopathological hallmark of CKD. Furthermore, we report that the extent of renal fibrosis, in terms of Col I, TGFβ, CCN2 and CCN3 expression and collagen I immunostaining, increases with increasing body temperature during ischemia and ischemia-time. Thus, varying these two main determinants of ischemic injury allows tuning the extent of the long-term fibrotic outcome in this model. Finally, in order to cover the whole practical finesse of ischemia-reperfusion and allow model and data transfer, we provide a referenced overview on crucial technical issues (incl. anaesthesia, analgesia, and pre- and post-operative care) with the specific aim of putting starters in the right direction of implementing ischemia in their research and stimulate them, as well as the community, to have a critical view on ischemic literature data. PMID:27007127

  18. A metabolic index of ischemic injury for perfusion-recovery of cadaveric rat livers.

    PubMed

    Perk, Sinem; Izamis, Maria-Louisa; Tolboom, Herman; Uygun, Basak; Berthiaume, Francois; Yarmush, Martin L; Uygun, Korkut

    2011-01-01

    With over 110,000 patients waiting for organ transplantation, the current crisis in organ transplantation is based on a lack of donors after brain-death (DBD). A very large alternative pool of donor organs that remain untapped are the donors after cardiac death (DCD), recovered after cardiac activity has ceased and therefore sustained some ischemic injury. Machine perfusion has been proposed as a novel modality of organ preservation and treatment to render such cadaveric organs, and in particular livers, transplantable. Two key issues that remain unaddressed are how to assess whether a DCD liver is damaged beyond repair, and whether machine perfusion has rendered an injured organ sufficiently viable for transplantation. In this work, we present a metabolic analysis of the transient responses of cadaveric rat livers during normothermic machine perfusion (NMP), and develop an index of ischemia that enables evaluation of the organ ischemic injury level. Further, we perform a discriminant analysis to construct a classification algorithm with >0.98 specificity to identify whether a given perfused liver is ischemic or fresh, in effect a precursor for an index of transplantability and a basis for the use of statistical process control measures for automated feedback control of treatment of ischemic injury in DCD livers. The analyses yield an index based on squared prediction error (SPE) as log(SPE) >1.35 indicating ischemia. The differences between metabolic functions of fresh and ischemic livers during perfusion are outlined and the metabolites that varied significantly for ischemic livers are identified as ornithine, arginine, albumin and tyrosine. PMID:22194843

  19. A Metabolic Index of Ischemic Injury for Perfusion-Recovery of Cadaveric Rat Livers

    PubMed Central

    Tolboom, Herman; Uygun, Basak; Berthiaume, Francois; Yarmush, Martin L.; Uygun, Korkut

    2011-01-01

    With over 110,000 patients waiting for organ transplantation, the current crisis in organ transplantation is based on a lack of donors after brain-death (DBD). A very large alternative pool of donor organs that remain untapped are the donors after cardiac death (DCD), recovered after cardiac activity has ceased and therefore sustained some ischemic injury. Machine perfusion has been proposed as a novel modality of organ preservation and treatment to render such cadaveric organs, and in particular livers, transplantable. Two key issues that remain unaddressed are how to assess whether a DCD liver is damaged beyond repair, and whether machine perfusion has rendered an injured organ sufficiently viable for transplantation. In this work, we present a metabolic analysis of the transient responses of cadaveric rat livers during normothermic machine perfusion (NMP), and develop an index of ischemia that enables evaluation of the organ ischemic injury level. Further, we perform a discriminant analysis to construct a classification algorithm with >0.98 specificity to identify whether a given perfused liver is ischemic or fresh, in effect a precursor for an index of transplantability and a basis for the use of statistical process control measures for automated feedback control of treatment of ischemic injury in DCD livers. The analyses yield an index based on squared prediction error (SPE) as log(SPE) >1.35 indicating ischemia. The differences between metabolic functions of fresh and ischemic livers during perfusion are outlined and the metabolites that varied significantly for ischemic livers are identified as ornithine, arginine, albumin and tyrosine. PMID:22194843

  20. Neuroinflammation and Neuroimmune Dysregulation after Acute Hypoxic-Ischemic Injury of Developing Brain

    PubMed Central

    Bhalala, Utpal S.; Koehler, Raymond C.; Kannan, Sujatha

    2015-01-01

    Hypoxic-ischemic (HI) injury to developing brain results from birth asphyxia in neonates and from cardiac arrest in infants and children. It is associated with varying degrees of neurologic sequelae, depending upon the severity and length of HI. Global HI triggers a series of cellular and biochemical pathways that lead to neuronal injury. One of the key cellular pathways of neuronal injury is inflammation. The inflammatory cascade comprises activation and migration of microglia – the so-called “brain macrophages,” infiltration of peripheral macrophages into the brain, and release of cytotoxic and proinflammatory cytokines. In this article, we review the inflammatory and immune mechanisms of secondary neuronal injury after global HI injury to developing brain. Specifically, we highlight the current literature on microglial activation in relation to neuronal injury, proinflammatory and anti-inflammatory/restorative pathways, the role of peripheral immune cells, and the potential use of immunomodulators as neuroprotective compounds. PMID:25642419

  1. Chapter 7. Mouse models of ischemic angiogenesis and ischemia-reperfusion injury.

    PubMed

    Greenberg, Joshua I; Suliman, Ahmed; Barillas, Samuel; Angle, Niren

    2008-01-01

    Ischemia and ischemia-reperfusion (I/R) events are distinct but interrelated processes etiologic to the most prevalent human diseases. A delicate balance exists whereby ischemic injury can result in beneficial angiogenesis or in detrimental reperfusion injury overwhelming the organism. Here, we describe in vivo models of ischemia and ischemia-reperfusion injury with emphasis on murine hindlimb ischemia models. We also provide a brief introduction to murine myocardial ischemia experiments. Each model is described in the context of human disease. Emphasis is made on the strengths and weaknesses of the available techniques, particularly as it relates to data analysis, interpretation, and translational relevance. PMID:19007664

  2. SUR1-Associated Mechanisms Are Not Involved in Ischemic Optic Neuropathy 1 Day Post-Injury

    PubMed Central

    Nicholson, James D.; Guo, Yan; Bernstein, Steven L.

    2016-01-01

    Ischemia-reperfusion injury after central nervous system (CNS) injury presents a major health care challenge with few promising treatments. Recently, it has become possible to reduce edema after CNS injury by antagonizing a sulfonylurea receptor 1 (SUR1) regulated ion channel expressed after injury. SUR1 upregulation after injury is a necessary precondition for the formation of this channel, and has been implicated in white matter injury after clinical spinal cord trauma. Glibenclamide, an SUR1 antagonist, appears to have neuroprotective effect against cerebral stroke in an open-label small clinical trial and great effectiveness in reducing damage after varied experimental CNS injury models. Despite its importance in CNS injuries, SUR1 upregulation appears to play no part in rodent anterior ischemic optic neuropathy (rAION) injury as tested by real-time PCR and immunohistochemical staining of rAION-injured rat optic nerve (ON). Furthermore, the SUR1 antagonist glibenclamide administered immediately after rAION injury provided no protection to proximal ON microvasculature 1 day post-injury but may reduce optic nerve head edema in a manner unrelated to ON SUR1 expression. Our results suggest that there may be fundamental differences between rAION optic nerve ischemia and other CNS white matter injuries where SUR1 appears to play a role. PMID:27560494

  3. SUR1-Associated Mechanisms Are Not Involved in Ischemic Optic Neuropathy 1 Day Post-Injury.

    PubMed

    Nicholson, James D; Guo, Yan; Bernstein, Steven L

    2016-01-01

    Ischemia-reperfusion injury after central nervous system (CNS) injury presents a major health care challenge with few promising treatments. Recently, it has become possible to reduce edema after CNS injury by antagonizing a sulfonylurea receptor 1 (SUR1) regulated ion channel expressed after injury. SUR1 upregulation after injury is a necessary precondition for the formation of this channel, and has been implicated in white matter injury after clinical spinal cord trauma. Glibenclamide, an SUR1 antagonist, appears to have neuroprotective effect against cerebral stroke in an open-label small clinical trial and great effectiveness in reducing damage after varied experimental CNS injury models. Despite its importance in CNS injuries, SUR1 upregulation appears to play no part in rodent anterior ischemic optic neuropathy (rAION) injury as tested by real-time PCR and immunohistochemical staining of rAION-injured rat optic nerve (ON). Furthermore, the SUR1 antagonist glibenclamide administered immediately after rAION injury provided no protection to proximal ON microvasculature 1 day post-injury but may reduce optic nerve head edema in a manner unrelated to ON SUR1 expression. Our results suggest that there may be fundamental differences between rAION optic nerve ischemia and other CNS white matter injuries where SUR1 appears to play a role. PMID:27560494

  4. Excessive α-tocopherol exacerbates microglial activation and brain injury caused by acute ischemic stroke

    PubMed Central

    Khanna, Savita; Heigel, Mallory; Weist, Jessica; Gnyawali, Surya; Teplitsky, Seth; Roy, Sashwati; Sen, Chandan K.; Rink, Cameron

    2015-01-01

    The vitamin E family includes both tocopherols and tocotrienols, where α-tocopherol (αTOC) is the most bioavailable form. Clinical trials testing the therapeutic efficacy of high-dose αTOC against stroke have largely failed or reported negative outcomes when a “more is better” approach to supplementation (>400 IU/d) was used. This work addresses mechanisms by which supraphysiologic αTOC may contribute to stroke-induced brain injury. Ischemic stroke injury and the neuroinflammatory response were studied in tocopherol transfer protein-deficient mice maintained on a diet containing αTOC vitamin E at the equivalent human dose of 1680 IU/d. Ischemic stroke-induced brain injury was exacerbated in the presence of supraphysiologic brain αTOC levels. At 48 h after stroke, S100B and RAGE expression was increased in stroke-affected cortex of mice with elevated brain αTOC levels. Such increases were concomitant with aggravated microglial activation and neuroinflammatory signaling. A poststroke increase in markers of oxidative injury and neurodegeneration in the presence of elevated brain αTOC establish that at supraphysiologic levels, αTOC potentiates neuroinflammatory responses to acute ischemic stroke. Exacerbation of microglial activation by excessive αTOC likely depends on its unique cell signaling regulatory properties independent of antioxidant function. Against the background of clinical failure for high-dose αTOC, outcomes of this work identify risk for exacerbating stroke-induced brain injury as a result of supplementing diet with excessive levels of αTOC.—Khanna, S., Heigel,M., Weist, J., Gnyawali, S., Teplitsky, S., Roy, S., Sen, C. K., Rink, C. Excessive α-tocopherol exacerbates microglial activation and brain injury caused by acute ischemic stroke. PMID:25411436

  5. Hyperglycemia, p53 and mitochondrial pathway of apoptosis are involved in the susceptibility of diabetic models to ischemic acute kidney injury

    PubMed Central

    Peng, Jianping; Li, Xiaoning; Zhang, Dongshan; Chen, Jian-Kang; Su, Yunchao; Smith, Sylvia B.; Dong, Zheng

    2014-01-01

    Patients with chronic kidney diseases, including diabetic nephropathy, are more susceptible to acute kidney injury (AKI) and have a worse prognosis following AKI. However, the underlying mechanism is unclear. Here we tested whether diabetic mice were more sensitive to AKI and show that renal ischemia-reperfusion induced significantly more severe AKI and higher mortality in the streptozotocin and the Akita diabetic mouse models. The severity of AKI in the mice correlated with their blood glucose levels. In vitro, high glucose-conditioned renal proximal tubular cells showed higher apoptosis and caspase activation following ATP-depletion and hypoxic injury, accompanied by a heightened mitochondrial accumulation of Bax and release of cytochrome c. In response to injury, both glucose-conditioned renal proximal tubular cells and diabetic kidney tissues showed markedly higher p53 induction. Suppression of p53 diminished the sensitivity of high glucose-conditioned cells to acute injury in vitro. Moreover, blockade of p53 by pifithrin-α, siRNA, or proximal tubule-targeted gene ablation reduced ischemic AKI in diabetic mice. Insulin reduced blood glucose in diabetic mice and largely attenuated their AKI sensitivity. Thus, our results suggest the involvement of hyperglycemia, p53 and mitochondrial pathway of apoptosis in the susceptibility of diabetic models to AKI. PMID:24963915

  6. MicroRNA-378 Alleviates Cerebral Ischemic Injury by Negatively Regulating Apoptosis Executioner Caspase-3.

    PubMed

    Zhang, Nan; Zhong, Jie; Han, Song; Li, Yun; Yin, Yanling; Li, Junfa

    2016-01-01

    miRNAs have been linked to many human diseases, including ischemic stroke, and are being pursued as clinical diagnostics and therapeutic targets. Among the aberrantly expressed miRNAs in our previous report using large-scale microarray screening, the downregulation of miR-378 in the peri-infarct region of middle cerebral artery occluded (MCAO) mice can be reversed by hypoxic preconditioning (HPC). In this study, the role of miR-378 in the ischemic injury was further explored. We found that miR-378 levels significantly decreased in N2A cells following oxygen-glucose deprivation (OGD) treatment. Overexpression of miR-378 significantly enhanced cell viability, decreased TUNEL-positive cells and the immunoreactivity of cleaved-caspase-3. Conversely, downregulation of miR-378 aggravated OGD-induced apoptosis and ischemic injury. By using bioinformatic algorithms, we discovered that miR-378 may directly bind to the predicted 3'-untranslated region (UTR) of Caspase-3 gene. The protein level of caspase-3 increased significantly upon OGD treatment, and can be downregulated by pri-miR-378 transfection. The luciferase reporter assay confirmed the binding of miR-378 to the 3'-UTR of Caspase-3 mRNA and repressed its translation. In addition, miR-378 agomir decreased cleaved-caspase-3 ratio, reduced infarct volume and neural cell death induced by MCAO. Furthermore, caspase-3 knockdown could reverse anti-miR-378 mediated neuronal injury. Taken together, our data demonstrated that miR-378 attenuated ischemic injury by negatively regulating the apoptosis executioner, caspase-3, providing a potential therapeutic target for ischemic stroke. PMID:27598143

  7. Antineoplastic Treatment and Renal Injury: An Update on Renal Pathology Due to Cytotoxic and Targeted Therapies.

    PubMed

    Troxell, Megan L; Higgins, John P; Kambham, Neeraja

    2016-09-01

    Cancer patients experience kidney injury from multiple sources, including the tumor itself, diagnostic procedures, hypovolemia, infection, and drug exposure, superimposed upon baseline chronic damage. This review will focus on cytotoxic or targeted chemotherapy-associated renal injury. In this setting, tubulointerstitial injury and thrombotic microangiopathy (vascular injury) are more common than other forms of kidney injury including glomerular. Cisplatin, pemetrexed, and ifosfamide are well-known causes of acute tubular injury/necrosis. Acute interstitial nephritis seems underrecognized in this clinical setting. Interstitial nephritis is emerging as an "immune-related adverse effect" (irAE's) with immune checkpoint inhibitors in small numbers of patients. Acute kidney injury is rarely reported with targeted therapies such as BRAF inhibitors (vemurafinib, dabrafenib), ALK inhibitors (crizotinib), and mTOR inhibitors (everolimus, temsirolimus), but additional biopsy data are needed. Tyrosine kinase inhibitors and monoclonal antibodies that block the vascular endothelial growth factor pathway are most commonly associated with thrombotic microangiopathy. Other causes of thrombotic microangiopathy in the cancer patients include cytotoxic chemotherapies such as gemcitabine and mitomycin C, hematopoietic stem cell transplant, and cancer itself (usually high-stage adenocarcinoma with marrow and vascular invasion). Cancer patients are historically underbiopsied, but biopsy can reveal type, acuity, and chronicity of renal injury, and facilitate decisions concerning continuation of chemotherapy and/or initiation of renoprotective therapy. Biopsy may also reveal unrelated and unanticipated findings in need of treatment. PMID:27403615

  8. SALT SENSITIVITY IN RESPONSE TO RENAL INJURY REQUIRES RENAL ANGIOTENSIN-CONVERTING ENZYME

    PubMed Central

    Giani, Jorge F.; Bernstein, Kenneth E.; Janjulia, Tea; Han, Jiyang; Toblli, Jorge E.; Shen, Xiao Z.; Rodriguez-Iturbe, Bernardo; McDonough, Alicia A.; Gonzalez-Villalobos, Romer A.

    2015-01-01

    Recent evidence indicates that salt-sensitive hypertension can result from a subclinical injury that impairs the kidneys’ capacity to properly respond to a high salt diet. However, how this occurs is not well understood. Here, we showed that while previously salt resistant wild-type mice became salt-sensitive after the induction of renal injury with the nitric oxide synthase inhibitor Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME); mice lacking renal angiotensin-converting enzyme, exposed to the same insult, did not become hypertensive when faced with a sodium load. This is because the activity of renal angiotensin-converting enzyme plays a critical role in: 1) augmenting the local pool of angiotensin II and, 2) the establishment of the anti-natriuretic state via modulation of glomerular filtration rate and sodium tubular transport. Thus, this study demonstrates that the presence of renal angiotensin-converting enzyme plays a pivotal role in the development of salt sensitivity in response to renal injury. PMID:26150439

  9. MG53 permeates through blood-brain barrier to protect ischemic brain injury

    PubMed Central

    Li, Haichang; Han, Yu; Chen, Ken; Wang, Zhen; Zeng, Jing; Liu, Yukai; Wang, Xinquan; Li, Yu; He, Duofen; Lin, Peihui; Zhou, Xinyu; Park, Ki Ho; Bian, Zehua; Chen, Zhishui; Gong, Nianqiao; Tan, Tao; Zhou, Jingsong; Zhang, Meng; Ma, Jianjie; Zeng, Chunyu

    2016-01-01

    Ischemic injury to neurons represents the underlying cause of stroke to the brain. Our previous studies identified MG53 as an essential component of the cell membrane repair machinery. Here we show that the recombinant human (rh)MG53 protein facilitates repair of ischemia-reperfusion (IR) injury to the brain. MG53 rapidly moves to acute injury sites on neuronal cells to form a membrane repair patch. IR-induced brain injury increases permeability of the blood-brain-barrier, providing access of MG53 from blood circulation to target the injured brain tissues. Exogenous rhMG53 protein can protect cultured neurons against hypoxia/reoxygenation-induced damages. Transgenic mice with increased levels of MG53 in the bloodstream are resistant to IR-induced brain injury. Intravenous administration of rhMG53, either prior to or after ischemia, can effectively alleviate brain injuries in rats. rhMG53-mediated neuroprotection involves suppression of apoptotic neuronal cell death, as well as activation of the pro-survival RISK signaling pathway. Our data indicate a physiological function for MG53 in the brain and suggest that targeting membrane repair or RISK signaling may be an effective means to treat ischemic brain injury. PMID:26967557

  10. Mitochondrial dysfunction in inherited renal disease and acute kidney injury.

    PubMed

    Emma, Francesco; Montini, Giovanni; Parikh, Samir M; Salviati, Leonardo

    2016-05-01

    Mitochondria are increasingly recognized as key players in genetic and acquired renal diseases. Most mitochondrial cytopathies that cause renal symptoms are characterized by tubular defects, but glomerular, tubulointerstitial and cystic diseases have also been described. For example, defects in coenzyme Q10 (CoQ10) biosynthesis and the mitochondrial DNA 3243 A>G mutation are important causes of focal segmental glomerulosclerosis in children and in adults, respectively. Although they sometimes present with isolated renal findings, mitochondrial diseases are frequently associated with symptoms related to central nervous system and neuromuscular involvement. They can result from mutations in nuclear genes that are inherited according to classic Mendelian rules or from mutations in mitochondrial DNA, which are transmitted according to more complex rules of mitochondrial genetics. Diagnosis of mitochondrial disorders involves clinical characterization of patients in combination with biochemical and genetic analyses. In particular, prompt diagnosis of CoQ10 biosynthesis defects is imperative because of their potentially reversible nature. In acute kidney injury (AKI), mitochondrial dysfunction contributes to the physiopathology of tissue injury, whereas mitochondrial biogenesis has an important role in the recovery of renal function. Potential therapies that target mitochondrial dysfunction or promote mitochondrial regeneration are being developed to limit renal damage during AKI and promote repair of injured tissue. PMID:26804019

  11. Enhanced recovery from chronic ischemic injury by bone marrow cells in a rat model of ischemic stroke.

    PubMed

    Yoo, Jongman; Seo, Jin-Ju; Eom, Jang-Hyeon; Hwang, Dong-Youn

    2015-01-01

    Even after decades of intensive studies, therapeutic options for patients with stroke are rather limited. Thrombolytic drugs effectively treat the very acute stage of stroke, and several neuroprotectants that are designed to treat secondary injury following stroke are being tested in clinical trials. However, these pharmacological approaches primarily focus on acute stroke recovery, and few options are available for treating chronic stroke patients. In recent years, stem cell-mediated regenerative approaches have emerged as promising therapeutic strategies for treating the chronic stage of stroke. In this study, we examined whether systemically administered bone marrow cells (BMCs) could have beneficial effects in a rat model of chronic ischemia. Our transplantation experiments using BMCs obtained from ischemic donor rats showed functional and structural recovery during the chronic stage of stroke. BMC-mediated neural proliferation was prominent in the brains of rats with chronic stroke, and most of the new cells eventually became neurons instead of astrocytes. BMC-mediated enhanced neural proliferation coincided with a significant reduction (∼50%) in the number of activated microglia, which is consistent with previous reports of enhanced neural proliferation being linked to microglial inactivation. Strikingly, approximately 57% of the BMCs that infiltrated the chronic ischemic brain were CD25(+) cells, suggesting that these cells may exert the beneficial effects associated with BMC transplantation. Based on the reported anti-inflammatory role of CD25(+) regulatory T-cells in acute experimental stroke, we propose a working model delineating the positive effects of BMC transplantation during the chronic phase of stroke; infiltrating BMCs (mostly CD25(+) cells) reduce activated microglia, which leads to enhanced neural proliferation and enhanced recovery from neuronal damage in this rat model of chronic stroke. This study provides valuable insights into the effect

  12. Amelioration of myocardial ischemic reperfusion injury with Calendula officinalis.

    PubMed

    Ray, Diptarka; Mukherjee, Subhendu; Falchi, Mario; Bertelli, Aldo; Das, Dipak K

    2010-12-01

    Calendula officinalis of family Asteraceae, also known as marigold, has been widely used from time immemorial in Indian and Arabic cultures as an anti-inflammatory agent to treat minor skin wound and infections, burns, bee stings, sunburn and cancer. At a relatively high dose, calendula can lower blood pressure and cholesterol. Since inflammatory responses are behind many cardiac diseases, we sought to evaluate if calendula could be cardioprotective against ischemic heart disease Two groups of hearts were used: the treated rat hearts were perfused with calendula solution at 50 mM in KHB buffer (in mM: sodium chloride 118, potassium chloride 4.7, calcium chloride 1.7, sodium bicarbonate 25, potassium biphosphate 0.36, magnesium sulfate 1.2, and glucose 10) for 15 min prior to subjecting the heart to ischemia, while the control group was perfused with the buffer only. Calendula achieved cardioprotection by stimulating left ventricular developed pressure and aortic flow as well as by reducing myocardial infarct size and cardiomyocyte apoptosis. Cardioprotection appears to be achieved by changing ischemia reperfusion-mediated death signal into a survival signal by modulating antioxidant and anti-inflammatory pathways as evidenced by the activation of Akt and Bcl2 and depression of TNFα. The results further strengthen the concept of using natural products in degeneration diseases like ischemic heart disease. PMID:20874690

  13. Inhibition of cyclophilin D by cyclosporin A promotes retinal ganglion cell survival by preventing mitochondrial alteration in ischemic injury

    PubMed Central

    Kim, S Y; Shim, M S; Kim, K-Y; Weinreb, R N; Wheeler, L A; Ju, W-K

    2014-01-01

    Cyclosporin A (CsA) inhibits the opening of the mitochondrial permeability transition pore (MPTP) by interacting with cyclophilin D (CypD) and ameliorates neuronal cell death in the central nervous system against ischemic injury. However, the molecular mechanisms underlying CypD/MPTP opening-mediated cell death in ischemic retinal injury induced by acute intraocular pressure (IOP) elevation remain unknown. We observed the first direct evidence that acute IOP elevation significantly upregulated CypD protein expression in ischemic retina at 12 h. However, CsA prevented the upregulation of CypD protein expression and promoted retinal ganglion cell (RGC) survival against ischemic injury. Moreover, CsA blocked apoptotic cell death by decreasing cleaved caspase-3 protein expression in ischemic retina. Of interest, although the expression level of Bcl-xL protein did not show a significant change in ischemic retina treated with vehicle or CsA at 12 h, ischemic damage induced the reduction of Bcl-xL immunoreactivity in RGCs. More importantly, CsA preserved Bcl-xL immunoreactivity in RGCs of ischemic retina. In parallel, acute IOP elevation significantly increased phosphorylated Bad (pBad) at Ser112 protein expression in ischemic retina at 12 h. However, CsA significantly preserved pBad protein expression in ischemic retina. Finally, acute IOP elevation significantly increased mitochondrial transcription factor A (Tfam) protein expression in ischemic retina at 12 h. However, CsA significantly preserved Tfam protein expression in ischemic retina. Studies on mitochondrial DNA (mtDNA) content in ischemic retina showed that there were no statistically significant differences in mtDNA content among control and ischemic groups treated with vehicle or CsA. Therefore, these results provide evidence that the activation of CypD-mediated MPTP opening is associated with the apoptotic pathway and the mitochondrial alteration in RGC death of ischemic retinal injury. On the basis

  14. Genetic Ablation of Pannexin1 Protects Retinal Neurons from Ischemic Injury

    PubMed Central

    Dvoriantchikova, Galina; Ivanov, Dmitry; Barakat, David; Grinberg, Alexander; Wen, Rong; Slepak, Vladlen Z.; Shestopalov, Valery I.

    2012-01-01

    Pannexin1 (Panx1) forms large nonselective membrane channel that is implicated in paracrine and inflammatory signaling. In vitro experiments suggested that Panx1 could play a key role in ischemic death of hippocampal neurons. Since retinal ganglion cells (RGCs) express high levels of Panx1 and are susceptible to ischemic induced injury, we hypothesized that Panx1 contributes to rapid and selective loss of these neurons in ischemia. To test this hypothesis, we induced experimental retinal ischemia followed by reperfusion in live animals with the Panx1 channel genetically ablated either in the entire mouse (Panx1 KO), or only in neurons using the conditional knockout (Panx1 CKO) technology. Here we report that two distinct neurotoxic processes are induced in RGCs by ischemia in the wild type mice but are inactivated in Panx1KO and Panx1 CKO animals. First, the post-ischemic permeation of RGC plasma membranes is suppressed, as assessed by dye transfer and calcium imaging assays ex vivo and in vitro. Second, the inflammasome-mediated activation of caspase-1 and the production of interleukin-1β in the Panx1 KO retinas are inhibited. Our findings indicate that post-ischemic neurotoxicity in the retina is mediated by previously uncharacterized pathways, which involve neuronal Panx1 and are intrinsic to RGCs. Thus, our work presents the in vivo evidence for neurotoxicity elicited by neuronal Panx1, and identifies this channel as a new therapeutic target in ischemic pathologies. PMID:22384122

  15. Sex-dependent effects of sleep deprivation on myocardial sensitivity to ischemic injury.

    PubMed

    Zoladz, Phillip R; Krivenko, Anna; Eisenmann, Eric D; Bui, Albert D; Seeley, Sarah L; Fry, Megan E; Johnson, Brandon L; Rorabaugh, Boyd R

    2016-01-01

    Sleep deprivation is associated with increased risk of myocardial infarction. However, it is unknown whether the effects of sleep deprivation are limited to increasing the likelihood of experiencing a myocardial infarction or if sleep deprivation also increases the extent of myocardial injury. In this study, rats were deprived of paradoxical sleep for 96 h using the platform-over-water method. Control rats were subjected to the same condition except the control platform was large enough for the rats to sleep. Hearts from sleep deprived and control rats were subjected to 20 min ischemia on a Langendorff isolated heart system. Infarct size and post ischemic recovery of contractile function were unaffected by sleep deprivation in male hearts. In contrast, hearts from sleep-deprived females exhibited significantly larger infarcts than hearts from control females. Post ischemic recovery of rate pressure product and + dP/dT were significantly attenuated by sleep deprivation in female hearts, and post ischemic recovery of end diastolic pressure was significantly elevated in hearts from sleep deprived females compared to control females, indicating that post ischemic recovery of both systolic and diastolic function were worsened by sleep deprivation. These data provide evidence that sleep deprivation increases the extent of ischemia-induced injury in a sex-dependent manner. PMID:26953626

  16. The role of Na+/Ca2+ exchanger subtypes in neuronal ischemic injury.

    PubMed

    Shenoda, Botros

    2015-06-01

    The Na(+)/Ca(2+) exchanger (NCX) plays an important role in the maintenance of Na(+) and Ca(2+) homeostasis in most cells including neurons under physiological and pathological conditions. It exists in three subtypes (NCX1-3) with different tissue distributions but all of them are present in the brain. NCX transports Na(+) and Ca(2+) in either Ca(2+)-efflux (forward) or Ca(2+)-influx (reverse) mode, depending on membrane potential and transmembrane ion gradients. During neuronal ischemia, Na(+) and Ca(2+) ionic disturbances favor NCX to work in reverse mode, giving rise to increased intracellular Ca(2+) levels, while it may regain its forward mode activity on reperfusion. The exact significance of NCX in neuronal ischemic and reperfusion states remains unclear. The differential role of NCX subtypes in ischemic neuronal injury has been extensively investigated using various pharmacological tools as well as genetic models. This review discusses the mode of action of NCX in ischemic and reperfusion states, the differential roles played by NCX subtypes in these states as well as the role of NCX in pre- and postconditioning. NCX subtypes carry variable roles in ischemic injury. Furthermore, the mode of action of each subtype varies in ischemia and reperfusion states. Thus, therapeutic targeting of NCX in stroke should be based on appropriate timing of the administration of NCX subtype-specific strategies. PMID:25860439

  17. Treatment with Isorhamnetin Protects the Brain Against Ischemic Injury in Mice.

    PubMed

    Zhao, Jin-Jing; Song, Jin-Qing; Pan, Shu-Yi; Wang, Kai

    2016-08-01

    Ischemic stroke is a major cause of morbidity and mortality, yet lacks effective neuroprotective treatments. The aim of this work was to investigate whether treatment with isorhamnetin protected the brain against ischemic injury in mice. Experimental stroke mice underwent the filament model of middle cerebral artery occlusion with reperfusion. Treatment with isorhamnetin or vehicle was initiated immediately at the onset of reperfusion. It was found that treatment of experimental stroke mice with isorhamnetin reduced infarct volume and caspase-3 activity (a biomarker of apoptosis), and improved neurological function recovery. Treatment of experimental stroke mice with isorhamnetin attenuated cerebral edema, improved blood-brain barrier function, and upregulated gene expression of tight junction proteins including occludin, ZO-1, and claudin-5. Treatment of experimental stroke mice with isorhamnetin activated Nrf2/HO-1, suppressed iNOS/NO, and led to reduced formation of MDA and 3-NT in ipsilateral cortex. In addition, treatment of experimental stroke mice with isorhamnetin suppressed activity of MPO (a biomarker of neutrophil infiltration) and reduced protein levels of IL-1β, IL-6, and TNF-α in ipsilateral cortex. Furthermore, it was found that treatment of experimental stroke mice with isorhamnetin reduced mRNA and protein expression of NMDA receptor subunit NR1 in ipsilateral cortex. In conclusion, treatment with isorhamnetin protected the brain against ischemic injury in mice. Isorhamnetin could thus be envisaged as a countermeasure for ischemic stroke but remains to be tested in humans. PMID:27161367

  18. The influence of warm and cold ischemic time on the outcome of cadaveric renal transplantation.

    PubMed

    Vroemen, J P; van der Vliet, J A; Cohen, B; Persijn, G G; Lansbergen, Q; Kootstra, G

    1984-01-01

    The influence of warm and cold ischemic time (WIT and CIT) on renal allograft function and allograft survival rates was analyzed from the Eurotransplant data. From 1977 through 1980 renal allograft recipients were divided into three groups, according to the length of the WIT of their graft: group I, 0-10 min (n = 2,636); group II, 11-20 min (n = 108); group III, 21-35 min (n = 17). Differences in graft function or graft survival have not been observed between these groups. It is concluded that donor kidneys with a WIT up to 20 min are acceptable for transplantation. The transplantation results in group III suggest that 35 min is a safe limit for acceptance, but the small number of transplantations in this group does not justify a firm conclusion. A combined analysis of warm and cold ischemia shows that simple cold storage up to 50 h is safe and acceptable, provided that warm ischemia is kept minimal (less than 10 min). It seems advisable to keep hypothermic preservation within the limit of 30 h, when WIT exceeds 10 min. PMID:6373296

  19. Inhibition of miR-15 Protects Against Cardiac Ischemic Injury

    PubMed Central

    Hullinger, Thomas G.; Montgomery, Rusty L.; Seto, Anita G.; Dickinson, Brent A.; Semus, Hillary M.; Lynch, Joshua M.; Dalby, Christina M.; Robinson, Kathryn; Stack, Christianna; Latimer, Paul A.; Hare, Joshua M.; Olson, Eric N.; van Rooij, Eva

    2012-01-01

    Rationale Myocardial infarction (MI) is a leading cause of death worldwide. Because endogenous cardiac repair mechanisms are not sufficient for meaningful tissue regeneration, MI results in loss of cardiac tissue and detrimental remodeling events. MicroRNAs (miRNAs) are small, noncoding RNAs that regulate gene expression in a sequence dependent manner. Our previous data indicate that miRNAs are dysregulated in response to ischemic injury of the heart and actively contribute to cardiac remodeling after MI. Objective This study was designed to determine whether miRNAs are dysregulated on ischemic damage in porcine cardiac tissues and whether locked nucleic acid (LNA)-modified anti-miR chemistries can target cardiac expressed miRNAs to therapeutically inhibit miR-15 on ischemic injury. Methods and Results Our data indicate that the miR-15 family, which includes 6 closely related miRNAs, is regulated in the infarcted region of the heart in response to ischemia-reperfusion injury in mice and pigs. LNA-modified chemistries can effectively silence miR-15 family members in vitro and render cardiomyocytes resistant to hypoxia-induced cardiomyocyte cell death. Correspondingly, systemic delivery of miR-15 anti-miRs dose-dependently represses miR-15 in cardiac tissue of both mice and pigs, whereas therapeutic targeting of miR-15 in mice reduces infarct size and cardiac remodeling and enhances cardiac function in response to MI. Conclusions Oligonucleotide-based therapies using LNA-modified chemistries for modulating cardiac miRNAs in the setting of heart disease are efficacious and validate miR-15 as a potential therapeutic target for the manipulation of cardiac remodeling and function in the setting of ischemic injury. PMID:22052914

  20. Prenatal methamphetamine differentially alters myocardial sensitivity to ischemic injury in male and female adult hearts.

    PubMed

    Rorabaugh, Boyd R; Seeley, Sarah L; Bui, Albert D; Sprague, Lisanne; D'Souza, Manoranjan S

    2016-02-15

    Methamphetamine is one of the most common illicit drugs abused during pregnancy. The neurological effects of prenatal methamphetamine are well known. However, few studies have investigated the potential effects of prenatal methamphetamine on adult cardiovascular function. Previous work demonstrated that prenatal cocaine exposure increases sensitivity of the adult heart to ischemic injury. Methamphetamine and cocaine have different mechanisms of action, but both drugs exert their effects by increasing dopaminergic and adrenergic receptor stimulation. Thus the goal of this study was to determine whether prenatal methamphetamine also worsens ischemic injury in the adult heart. Pregnant rats were injected with methamphetamine (5 mg·kg(-1)·day(-1)) or saline throughout pregnancy. When pups reached 8 wk of age, their hearts were subjected to ischemia and reperfusion by means of a Langendorff isolated heart system. Prenatal methamphetamine had no significant effect on infarct size, preischemic contractile function, or postischemic recovery of contractile function in male hearts. However, methamphetamine-treated female hearts exhibited significantly larger infarcts and significantly elevated end-diastolic pressure during recovery from ischemia. Methamphetamine significantly reduced protein kinase Cε expression and Akt phosphorylation in female hearts but had no effect on these cardioprotective proteins in male hearts. These data indicate that prenatal methamphetamine differentially affects male and female sensitivity to myocardial ischemic injury and alters cardioprotective signaling proteins in the adult heart. PMID:26683901

  1. The role of morphine in a rat model of hypoxic-ischemic injury.

    PubMed

    Festekjian, Ara; Ashwal, Stephen; Obenaus, Andre; Angeles, Danilyn M; Denmark, T Kent

    2011-08-01

    We investigated whether morphine plays a neuroprotective role in a neonatal rat pup model of bilateral carotid artery occlusion with hypoxia. At postnatal day 10, rats received either morphine (n = 7), naloxone (n = 7), or saline placebo (n = 15) after hypoxic-ischemic injury. Survival (days), weight gain and animal testing (negative geotaxis, surface righting, and rotarod) were compared between treatment groups. Lesion volume was delineated with magnetic resonance imaging at days 7 and 28-57 after injury. Survival in rats treated with morphine, naloxone, or saline was, respectively, 14, 29, and 73%. Median number of days of survival after bilateral carotid artery occlusion with hypoxia treated with morphine was 4 (95% confidence interval 4 to 22), with naloxone was 3 (95% confidence interval -1.4 to 21), and with placebo was 28 (95% confidence interval 18 to 28). There were no statistically significant differences in magnetic resonance imaging-derived ischemic lesion volumes, weight gain, or behavioral testing measures between the groups. Morphine was ineffective as a neuroprotectant in rat pups with severe hypoxic-ischemic injury and may have contributed to their decreased survival. PMID:21763946

  2. Ameliorative effects of Gualou Guizhi decoction on inflammation in focal cerebral ischemic-reperfusion injury

    PubMed Central

    ZHANG, YUQIN; ZHANG, SHENGNAN; LI, HUANG; HUANG, MEI; XU, WEI; CHU, KEDAN; CHEN, LIDIAN; CHEN, XIANWEN

    2015-01-01

    Gualou Guizhi decoction (GLGZD) is a well-established Traditional Chinese Medicinal formulation which has long been used to treat stroke in a clinical setting in China. The present study investigated the ameliorative effects of GLGZD on inflammation in focal cerebral ischemic-reperfusion injury. A rat model of middle cerebral artery occlusion (MCAO) was employed. Rats were administrated GLGZD (7.2 and 14.4 g/kg per day) or saline as control 2 h after reperfusion and daily over the following seven days. Neurological deficit score and screen test were evaluated at 1, 3, 5 and 7 days after MCAO. Brain infarct size and brain histological changes were observed via 2,3,5-triphenyltetrazolium chloride staining and regular hematoxylin & eosin staining. Furthermore, inflammation mediators and nuclear factor-κB (NF-κB) were investigated using ELISA and immunohistochemistry. GLGZD treatment significantly improved neurological function, ameliorated histological changes to the brain and decreased infarct size in focal cerebral ischemic-reperfusion injury. GLGZD was found to significantly reduce interleukin (IL)-1, tumor necrosis factor-α and NF-κB levels, while increasing levels of IL-10. In conclusion, the present study suggested that GLGZD has a neuroprotective effect on focal cerebral ischemic-reperfusion injury and this effect is likely to be associated with the anti-inflammatory function of GLGZD. PMID:25815894

  3. Birth Asphyxia and Hypoxic-Ischemic Brain Injury in the Preterm Infant.

    PubMed

    Laptook, Abbot R

    2016-09-01

    Birth asphyxia, also termed perinatal hypoxia-ischemia, is a modifiable condition as evidenced by improved outcomes of infants ≥36 weeks' gestation provided hypothermia treatment in randomized trials. Preterm animal models of asphyxia in utero demonstrate that hypothermia can provide short-term neuroprotection for the developing brain, supporting the interest in extending therapeutic hypothermia to preterm infants. This review focuses on the challenge of identifying preterm infants with perinatal asphyxia; the neuropathology of hypoxic-ischemic brain injury across extreme, moderate, and late preterm infants; and patterns of brain injury, use of therapeutic hypothermia, and approach to patient selection for neuroprotective treatments among preterm infants. PMID:27524452

  4. GM-CSF Promotes Macrophage Alternative Activation after Renal Ischemia/Reperfusion Injury

    PubMed Central

    Huynh, Larry; Marlier, Arnaud; Lee, Yashang; Moeckel, Gilbert W.; Cantley, Lloyd G.

    2015-01-01

    After kidney ischemia/reperfusion (I/R) injury, monocytes home to the kidney and differentiate into activated macrophages. Whereas proinflammatory macrophages contribute to the initial kidney damage, an alternatively activated phenotype can promote normal renal repair. The microenvironment of the kidney during the repair phase mediates the transition of macrophage activation from a proinflammatory to a reparative phenotype. In this study, we show that macrophages isolated from murine kidneys during the tubular repair phase after I/R exhibit an alternative activation gene profile that differs from the canonical alternative activation induced by IL-4–stimulated STAT6 signaling. This unique activation profile can be reproduced in vitro by stimulation of bone marrow-derived macrophages with conditioned media from serum-starved mouse proximal tubule cells. Secreted tubular factors were found to activate macrophage STAT3 and STAT5 but not STAT6, leading to induction of the unique alternative activation pattern. Using STAT3-deficient bone marrow-derived macrophages and pharmacologic inhibition of STAT5, we found that tubular cell-mediated macrophage alternative activation is regulated by STAT5 activation. Both in vitro and after renal I/R, tubular cells expressed GM-CSF, a known STAT5 activator, and this pathway was required for in vitro alternative activation of macrophages by tubular cells. Furthermore, administration of a neutralizing antibody against GM-CSF after renal I/R attenuated kidney macrophage alternative activation and suppressed tubular proliferation. Taken together, these data show that tubular cells can instruct macrophage activation by secreting GM-CSF, leading to a unique macrophage reparative phenotype that supports tubular proliferation after sterile ischemic injury. PMID:25388222

  5. A Smoothened receptor agonist is neuroprotective and promotes regeneration after ischemic brain injury

    PubMed Central

    Chechneva, O V; Mayrhofer, F; Daugherty, D J; Krishnamurty, R G; Bannerman, P; Pleasure, D E; Deng, W

    2014-01-01

    Ischemic stroke occurs as a result of blood supply interruption to the brain causing tissue degeneration, patient disabilities or death. Currently, treatment of ischemic stroke is limited to thrombolytic therapy with a narrow time window of administration. The sonic hedgehog (Shh) signaling pathway has a fundamental role in the central nervous system development, but its impact on neural cell survival and tissue regeneration/repair after ischemic stroke has not been well investigated. Here we report the neuroprotective properties of a small-molecule agonist of the Shh co-receptor Smoothened, purmorphamine (PUR), in the middle cerebral artery occlusion model of ischemic stroke. We found that intravenous administration of PUR at 6 h after injury was neuroprotective and restored neurological deficit after stroke. PUR promoted a transient upregulation of tissue-type plasminogen activator in injured neurons, which was associated with a reduction of apoptotic cell death in the ischemic cortex. We also observed a decrease in blood–brain barrier permeability after PUR treatment. At 14 d postinjury, attenuation of inflammation and reactive astrogliosis was found in PUR-treated animals. PUR increased the number of newly generated neurons in the peri-infarct and infarct area and promoted neovascularization in the ischemic zone. Notably, PUR treatment did not significantly alter the ischemia-induced level of Gli1, a Shh target gene of tumorigenic potential. Thus our study reports a novel pharmacological approach for postischemic treatment using a small-molecule Shh agonist, providing new insights into hedgehog signaling-mediated mechanisms of neuroprotection and regeneration after stroke. PMID:25341035

  6. Study on the Mechanism of mTOR-Mediated Autophagy during Electroacupuncture Pretreatment against Cerebral Ischemic Injury

    PubMed Central

    Wu, Zhou-Quan; Cui, Su-yang; Zhu, Liang

    2016-01-01

    This study is aimed at investigating the association between the electroacupuncture (EA) pretreatment-induced protective effect against early cerebral ischemic injury and autophagy. EA pretreatment can protect cerebral ischemic and reperfusion injuries, but whether the attenuation of early cerebral ischemic injury by EA pretreatment was associated with autophagy is not yet clear. This study used the middle cerebral artery occlusion model to monitor the process of ischemic injury. For rats in the EA pretreatment group, EA pretreatment was conducted at Baihui acupoint before ischemia for 30 min for 5 consecutive days. The results suggested that EA pretreatment significantly increased the expression of autophagy in the cerebral cortical area on the ischemic side of rats. But the EA pretreatment-induced protective effects on the brain could be reversed by the specific inhibitor 3-methyladenine of autophagy. Additionally, the Pearson correlation analysis indicated that the impact of EA pretreatment on p-mTOR (2481) was negatively correlated with its impact on autophagy. In conclusion, the mechanism of EA pretreatment at Baihui acupoint against cerebral ischemic injury is mainly associated with the upregulation of autophagy expression, and its regulation of autophagy may depend on mTOR-mediated signaling pathways. PMID:27547233

  7. Renovascular remodeling and renal injury after extended angiotensin II infusion.

    PubMed

    Casare, Fernando Augusto Malavazzi; Thieme, Karina; Costa-Pessoa, Juliana Martins; Rossoni, Luciana Venturini; Couto, Gisele Kruger; Fernandes, Fernanda Barrinha; Casarini, Dulce Elena; Oliveira-Souza, Maria

    2016-06-01

    Chronic angiotensin II (ANG II) infusion for 1 or 2 wk leads to progressive hypertension and induces inward hypertrophic remodeling in preglomerular vessels, which is associated with increased renal vascular resistance (RVR) and decreased glomerular perfusion. Considering the ability of preglomerular vessels to exhibit adaptive responses, the present study was performed to evaluate glomerular perfusion and renal function after 6 wk of ANG II infusion. To address this study, male Wistar rats were submitted to sham surgery (control) or osmotic minipump insertion (ANG II 200 ng·kg(-1)·min(-1), 42 days). A group of animals was treated or cotreated with losartan (10 mg·kg(-1)·day(-1)), an AT1 receptor antagonist, between days 28 and 42 Chronic ANG II infusion increased systolic blood pressure to 185 ± 4 compared with 108 ± 2 mmHg in control rats. Concomitantly, ANG II-induced hypertension increased intrarenal ANG II level and consequently, preglomerular and glomerular injury. Under this condition, ANG II enhanced the total renal plasma flow (RPF), glomerular filtration rate (GFR), urine flow and induced pressure natriuresis. These changes were accompanied by lower RVR and enlargement of the lumen of interlobular arteries and afferent arterioles, consistent with impairment of renal autoregulatory capability and outward preglomerular remodeling. The glomerular injury culminated with podocyte effacement, albuminuria, tubulointerstitial macrophage infiltration and intrarenal extracellular matrix accumulation. Losartan attenuated most of the effects of ANG II. Our findings provide new information regarding the contribution of ANG II infusion over 2 wk to renal hemodynamics and function via the AT1 receptor. PMID:26962104

  8. Mining the human urine proteome for monitoring renal transplant injury.

    PubMed

    Sigdel, Tara K; Gao, Yuqian; He, Jintang; Wang, Anyou; Nicora, Carrie D; Fillmore, Thomas L; Shi, Tujin; Webb-Robertson, Bobbie-Jo; Smith, Richard D; Qian, Wei-Jun; Salvatierra, Oscar; Camp, David G; Sarwal, Minnie M

    2016-06-01

    The human urinary proteome provides an assessment of kidney injury with specific biomarkers for different kidney injury phenotypes. In an effort to fully map and decipher changes in the urine proteome and peptidome after kidney transplantation, renal allograft biopsy matched urine samples were collected from 396 kidney transplant recipients. Centralized and blinded histology data from paired graft biopsies was used to classify urine samples into diagnostic categories of acute rejection, chronic allograft nephropathy, BK virus nephritis, and stable graft. A total of 245 urine samples were analyzed by liquid chromatography-mass spectrometry using isobaric Tags for Relative and Absolute Quantitation (iTRAQ) reagents. From a group of over 900 proteins identified in transplant injury, a set of 131 peptides were assessed by selected reaction monitoring for their significance in accurately segregating organ injury causation and pathology in an independent cohort of 151 urine samples. Ultimately, a minimal set of 35 proteins were identified for their ability to segregate the 3 major transplant injury clinical groups, comprising the final panel of 11 urinary peptides for acute rejection (93% area under the curve [AUC]), 12 urinary peptides for chronic allograft nephropathy (99% AUC), and 12 urinary peptides for BK virus nephritis (83% AUC). Thus, urinary proteome discovery and targeted validation can identify urine protein panels for rapid and noninvasive differentiation of different causes of kidney transplant injury, without the requirement of an invasive biopsy. PMID:27165815

  9. Severe hypertriglyceridemia does not protect from ischemic brain injury in gene-modified hypertriglyceridemic mice.

    PubMed

    Chen, Yong; Liu, Ping; Qi, Rong; Wang, Yu-Hui; Liu, George; Wang, Chun

    2016-05-15

    Hypertriglyceridemia (HTG) is a weak risk factor in primary ischemic stroke prevention. However, clinical studies have found a counterintuitive association between a good prognosis after ischemic stroke and HTG. This "HTG paradox" requires confirmation and further explanation. The aim of this study was to experimentally assess this paradox relationship using the gene-modified mice model of extreme HTG. We first used the human Apolipoprotein CIII transgenic (Tg-ApoCIII) mice and non-transgenic (Non-Tg) littermates to examine the effect of HTG on stroke. To our surprise, infarct size, neurological deficits, brain edema, BBB permeability, neuron density and lipid peroxidation were the same in Tg-ApoCIII mice and Non-Tg mice after temporary middle cerebral artery occlusion (tMCAO). In the late phase (21 days after surgery), no differences were found in brain atrophy, neurological dysfunctions, weight and mortality between the two groups. To confirm the results in Tg-ApoCIII mice, Glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1(GPIHBP1) knockout mice, another severe HTG mouse model, were used and yielded similar results. Our study demonstrates for the first time that extreme HTG does not affect ischemic brain injuries in the tMCAO mouse model, indicating that the association between HTG and good outcomes after ischemic stroke probably represents residual unmeasured confounding. Further clinical and prospective population-based studies are needed to explore variables that contribute to the paradox. PMID:26970521

  10. Treatment with Evasin-3 reduces atherosclerotic vulnerability for ischemic stroke, but not brain injury in mice

    PubMed Central

    Copin, Jean-Christophe; da Silva, Rafaela F; Fraga-Silva, Rodrigo A; Capettini, Luciano; Quintao, Silvia; Lenglet, Sébastien; Pelli, Graziano; Galan, Katia; Burger, Fabienne; Braunersreuther, Vincent; Schaller, Karl; Deruaz, Maud; Proudfoot, Amanda E; Dallegri, Franco; Stergiopulos, Nikolaos; Santos, Robson A S; Gasche, Yvan; Mach, François; Montecucco, Fabrizio

    2013-01-01

    Neutrophilic inflammation might have a pathophysiological role in both carotid plaque rupture and ischemic stroke injury. Here, we investigated the potential benefits of the CXC chemokine-binding protein Evasin-3, which potently inhibits chemokine bioactivity and related neutrophilic inflammation in two mouse models of carotid atherosclerosis and ischemic stroke, respectively. In the first model, the chronic treatment with Evasin-3 as compared with Vehicle (phosphate-buffered saline (PBS)) was investigated in apolipoprotein E-deficient mice implanted of a ‘cast' carotid device. In the second model, acute Evasin-3 treatment (5 minutes after cerebral ischemia onset) was assessed in mice subjected to transient left middle cerebral artery occlusion. Although CXCL1 and CXCL2 were upregulated in both atherosclerotic plaques and infarcted brain, only CXCL1 was detectable in serum. In carotid atherosclerosis, treatment with Evasin-3 was associated with reduction in intraplaque neutrophil and matrix metalloproteinase-9 content and weak increase in collagen as compared with Vehicle. In ischemic stroke, treatment with Evasin-3 was associated with reduction in ischemic brain neutrophil infiltration and protective oxidants. No other effects in clinical and histological outcomes were observed. We concluded that Evasin-3 treatment was associated with reduction in neutrophilic inflammation in both mouse models. However, Evasin-3 administration after cerebral ischemia onset failed to improve poststroke outcomes. PMID:23250107

  11. The feasibility of imaging myocardial ischemic/reperfusion injury using 99mTc-labeled duramycin in a porcine model

    PubMed Central

    Wang, Lei; Wang, Feng; Fang, Wei; Johnson, Steven E.; Audi, Said; Zimmer, Michael; Holly, Thomas A; Lee, Daniel; Zhu, Bao; Zhu, Haibo; Zhao, Ming

    2015-01-01

    When pathologically externalized, phosphatidylethanolamine (PE) is a potential surrogate marker for detecting tissue injuries. 99mTc-labeled duramycin is a peptide-based imaging agent that binds PE with high affinity and specificity. The goal of the current study was to investigate the clearance kinetics of 99mTc-labeled duramycin in a large animal model (normal pigs) and to assess its uptake in the heart using a pig model of myocardial ischemia-reperfusion injury. Methods The clearance and distribution of intravenously injected 99mTc-duramycin were characterized in sham-operated animals (n = 5). In a closed chest model of myocardial ischemia, coronary occlusion was induced by balloon angioplasty (n = 9). 99mTc-duramycin (10-15 mCi) was injected intravenously at 1 hour after reperfusion. SPECT/CT was acquired at 1 and 3 hours after injection. Cardiac tissues were analyzed for changes associated with acute cellular injuries. Autoradiography and gamma counting was used to determine radioactivity uptake. For the remaining animals, 99mTc-tetrafosamin scan was performed on the second day to identify the infarct site. Results Intravenously injected 99mTc-duramycin cleared from circulation predominantly via the renal/urinary tract with an α-phase half-life of 3.6 ± 0.3 minutes and β-phase half-life of 179.9 ± 64.7 minutes. In control animals, the ratios between normal heart and lung were 1.76 ± 0.21, 1.66 ± 0.22, 1.50 ± 0.20 and 1.75 ± 0.31 at 0.5, 1, 2 and 3 hours post injection, respectively. The ratios between normal heart and liver were 0.88 ± 0.13, 0.80 ± 0.13, 0.82 ± 0.19 and 0.88 ± 0.14. In vivo visualization of focal radioactivity uptake in the ischemic heart was attainable as early as 30 min post injection. The in vivo ischemic-to-normal uptake ratios were 3.57 ± 0.74 and 3.69 ± 0.91 at 1 and 3 hours post injection, respectively. Ischemic-to-lung ratios were 4.89 ± 0.85 and 4.93 ± 0.57; and ischemic-to-liver ratios were 2.05 ± 0.30 to 3.23 ± 0

  12. Ischemic preconditioning and inflammatory response syndrome after reperfusion injury: an experimental model in diabetic rats.

    PubMed

    Grigorescu, Bianca Liana; Georgescu, Anca Meda; Cioc, Adrian-Dan; Fodor, Raluca-Ştefania; Cotoi, Ovidiu Simion; Fodor, Pal; Copotoiu, Sanda Maria; Azamfirei, Leonard

    2015-01-01

    Quantification of local ischemia and inflammatory response syndrome correlated with histological changes associated with ischemia-reperfusion injury (IRI) after revascularization techniques. We included 12 adult male Wistar rats, aged eight weeks that were randomly divided into two groups. The first group acted as the control and at the second group, we induced diabetes by intraperitoneal streptozotocin administration (60 mg/kg). After eight weeks, the rats were subject to ischemic preconditioning for 10 minutes at three regular intervals. Twenty-four hours post-preconditioning, both groups were subject to ischemia for 20 minutes, followed by 30 minutes of reperfusion. Oxygen extraction was higher in Group 1, the arterio-venous CO2 gradient was higher in the control group, but not significant. The lactate production was higher in Group 1. The second group had a higher Na+ and also a significant difference in K+ values. Receptor for Advanced Glycation End (RAGE) values were higher in the second group but with no significant difference (RAGE1=0.32 ng/mL versus RAGE2=0.40 ng/mL). The muscle samples from the control group displayed significant rhabdomyolysis, damage to the nucleus, while the preconditioned group showed almost normal morphological characteristics. The lungs and kidneys were most damaged in the control group, with damage expressed as thickened alveolar septa, neutrophil infiltrates, eosinophilic precipitates in the proximal convolute tubule. Ischemic preconditioning significantly attenuates the ischemic reperfusion injury. PMID:26743274

  13. PPARα agonist, fenofibrate, ameliorates age-related renal injury.

    PubMed

    Kim, Eun Nim; Lim, Ji Hee; Kim, Min Young; Kim, Hyung Wook; Park, Cheol Whee; Chang, Yoon Sik; Choi, Bum Soon

    2016-08-01

    The kidney ages quickly compared with other organs. Expression of senescence markers reflects changes in the energy metabolism in the kidney. Two important issues in aging are mitochondrial dysfunction and oxidative stress. Peroxisome proliferator-activated receptor α (PPARα) is a member of the ligand-activated nuclear receptor superfamily. PPARα plays a major role as a transcription factor that regulates the expression of genes involved in various processes. In this study, 18-month-old male C57BL/6 mice were divided into two groups, the control group (n=7) and the fenofibrate-treated group (n=7) was fed the normal chow plus fenofibrate for 6months. The PPARα agonist, fenofibrate, improved renal function, proteinuria, histological change (glomerulosclerosis and tubular interstitial fibrosis), inflammation, and apoptosis in aging mice. This protective effect against age-related renal injury occurred through the activation of AMPK and SIRT1 signaling. The activation of AMPK and SIRT1 allowed for the concurrent deacetylation and phosphorylation of their target molecules and decreased the kidney's susceptibility to age-related changes. Activation of the AMPK-FOXO3a and AMPK-PGC-1α signaling pathways ameliorated oxidative stress and mitochondrial dysfunction. Our results suggest that activation of PPARα and AMPK-SIRT1 signaling may have protective effects against age-related renal injury. Pharmacological targeting of PPARα and AMPK-SIRT1 signaling molecules may prevent or attenuate age-related pathological changes in the kidney. PMID:27130813

  14. Acute Kidney Injury Associated with Renal Cell Carcinoma Complicated by Renal Vein and Inferior Vena Cava Involvement.

    PubMed

    Sugase, Taro; Akimoto, Tetsu; Kubo, Taro; Imai, Toshimi; Otani-Takei, Naoko; Miki, Takuya; Takeda, Shin-Ichi; Nukui, Akinori; Muto, Shigeaki; Morita, Tatsuo; Nagata, Daisuke

    2016-01-01

    Acute kidney injury (AKI) is caused by diverse pathologies, although it may occasionally result from concurrent renal efflux disturbances. We herein describe a case of AKI in a patient complicated by renal cell carcinoma (RCC) with renal vein and inferior vena cava (IVC) involvement. A neoplastic thrombus which disrupted the blood flow in the renal vein appeared to play a role in the rapid decline in the renal function. Such a scenario has rarely been mentioned in the previous literature describing the cases of RCC complicated by AKI. Concerns regarding the diagnostic and therapeutic strategies for RCC are also discussed. PMID:27580548

  15. Cerebrovascular autoregulation and neurologic injury in neonatal hypoxic-ischemic encephalopathy

    PubMed Central

    Howlett, Jessica A.; Northington, Frances J.; Gilmore, Maureen M.; Tekes, Aylin; Huisman, Thierry A.G.M.; Parkinson, Charlamaine; Chung, Shang-En; Jennings, Jacky M.; Jamrogowicz, Jessica J.; Larson, Abby C.; Lehmann, Christoph U.; Jackson, Eric; Brady, Ken M.; Koehler, Raymond C.; Lee, Jennifer K.

    2014-01-01

    Background Neonates with hypoxic-ischemic encephalopathy (HIE) are at risk of cerebral blood flow dysregulation. Our objective was to describe the relationship between autoregulation and neurologic injury in HIE. Methods Neonates with HIE had autoregulation monitoring with the hemoglobin volume index (HVx) during therapeutic hypothermia, rewarming, and the first 6 h of normothermia. The 5-mmHg range of mean arterial blood pressure (MAP) with best vasoreactivity (MAPOPT) was identified. The percentage of time spent with MAP below MAPOPT and deviation in MAP from MAPOPT were measured. Neonates received brain MRIs 3–7 days after treatment. MRIs were coded as no, mild, or moderate/severe injury in five regions. Results HVx identified MAPOPT in 79% (19/24), 77% (17/22), and 86% (18/21) of neonates during hypothermia, rewarming, and normothermia, respectively. Neonates with moderate/severe injury in paracentral gyri, white matter, basal ganglia, and thalamus spent a greater proportion of time with MAP below MAPOPT during rewarming than neonates with no or mild injury. Neonates with moderate/severe injury in paracentral gyri, basal ganglia, and thalamus had greater MAP deviation below MAPOPT during rewarming than neonates without injury. Conclusion Maintaining MAP within or above MAPOPT may reduce the risk of neurologic injuries in neonatal HIE. PMID:23942555

  16. Ischemic brain injury in hemodialysis patients: which is more dangerous, hypertension or intradialytic hypotension?

    PubMed

    McIntyre, Christopher W; Goldsmith, David J

    2015-06-01

    Abnormalities of cognitive function and high levels of depression incidence are characteristic of hemodialysis patients. Although previously attributed to the humoral effects of uremia, it is becoming increasingly appreciated that many elements of the overall disease state in CKD patients contribute to functional disturbances and physical brain injury. These factors range from those associated with the underlying primary diseases (cardiovascular, diabetes etc.) to those specifically associated with the requirement for dialysis (including consequences of the hemodialysis process itself). They are, however, predominantly ischemic threats to the integrity of brain tissue. These evolving insights are starting to allow nephrologists to appreciate the potential biological basis of dependency and depression in our patients, as well as develop and test new therapeutic approaches to this increasingly prevalent and important issue. This review aims to summarize the current understanding of brain injury in this setting, as well as examine recent advances being made in the modification of dialysis-associated brain injury. PMID:25853331

  17. Aluminum citrate prevents renal injury from calcium oxalate crystal deposition.

    PubMed

    Besenhofer, Lauren M; Cain, Marie C; Dunning, Cody; McMartin, Kenneth E

    2012-12-01

    Calcium oxalate monohydrate crystals are responsible for the kidney injury associated with exposure to ethylene glycol or severe hyperoxaluria. Current treatment strategies target the formation of calcium oxalate but not its interaction with kidney tissue. Because aluminum citrate blocks calcium oxalate binding and toxicity in human kidney cells, it may provide a different therapeutic approach to calcium oxalate-induced injury. Here, we tested the effects of aluminum citrate and sodium citrate in a Wistar rat model of acute high-dose ethylene glycol exposure. Aluminum citrate, but not sodium citrate, attenuated increases in urea nitrogen, creatinine, and the ratio of kidney to body weight in ethylene glycol-treated rats. Compared with ethylene glycol alone, the addition of aluminum citrate significantly increased the urinary excretion of both crystalline calcium and crystalline oxalate and decreased the deposition of crystals in renal tissue. In vitro, aluminum citrate interacted directly with oxalate crystals to inhibit their uptake by proximal tubule cells. These results suggest that treating with aluminum citrate attenuates renal injury in rats with severe ethylene glycol toxicity, apparently by inhibiting calcium oxalate's interaction with, and retention by, the kidney epithelium. PMID:23138489

  18. Aluminum Citrate Prevents Renal Injury from Calcium Oxalate Crystal Deposition

    PubMed Central

    Besenhofer, Lauren M.; Cain, Marie C.; Dunning, Cody

    2012-01-01

    Calcium oxalate monohydrate crystals are responsible for the kidney injury associated with exposure to ethylene glycol or severe hyperoxaluria. Current treatment strategies target the formation of calcium oxalate but not its interaction with kidney tissue. Because aluminum citrate blocks calcium oxalate binding and toxicity in human kidney cells, it may provide a different therapeutic approach to calcium oxalate-induced injury. Here, we tested the effects of aluminum citrate and sodium citrate in a Wistar rat model of acute high-dose ethylene glycol exposure. Aluminum citrate, but not sodium citrate, attenuated increases in urea nitrogen, creatinine, and the ratio of kidney to body weight in ethylene glycol–treated rats. Compared with ethylene glycol alone, the addition of aluminum citrate significantly increased the urinary excretion of both crystalline calcium and crystalline oxalate and decreased the deposition of crystals in renal tissue. In vitro, aluminum citrate interacted directly with oxalate crystals to inhibit their uptake by proximal tubule cells. These results suggest that treating with aluminum citrate attenuates renal injury in rats with severe ethylene glycol toxicity, apparently by inhibiting calcium oxalate’s interaction with, and retention by, the kidney epithelium. PMID:23138489

  19. Transforming growth factor-β1 promotes homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury

    PubMed Central

    Si, Xiaoyun; Liu, Ximing; Li, Jingjing; Wu, Xiaoyan

    2015-01-01

    Backgrounds: Acute ischemia reperfusion-induced kidney injury is a common cause of acute renal failure, and it is also an important cause of delayed recovery of transplanted kidney functions and even loss of function. However, there is no effective treatment method in clinical applications presently. Objective: The objective was to investigate effects of transforming growth factor-β1 on homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury. Methods: Effects of TGF-β1 over-expression in MSCs on expression of CXCR4 and chemotactic effect to SDF-1 were investigated by in vitro transmembrane chemotaxis. Anti-TGF-β1 antibody was incubated with ischemia reperfusion injury renal tissue homogenate and effects of anti-TGF-β1 antibody were observed. In addition, effects of TGF-β1 gene transfection and anti-CXCR4 antibody treatment in MSCs on expression of SDF-1/CXCR4 axis of renal tissues and damage repair were further explored. Results: Expression of TGF-β1 mRNA in the IRI group increased significantly, and MSCs transplantation could enhance expression of CXCR4 mRNA in rats of the IRI group, the expression of CXCR4 can be decreased by the anti-TGF-β1 antibody and the anti-CXCR4 antibody. TGF-β1 induced homing of MSCs in repair of renal ischemic reperfusion injury by regulating expression of CXCR4 on cell membranes. Blue fluorescence of DAPI-positive MSCs cells of renal parenchyma in the IRI+MSC group was enhanced significantly, which was significantly inhibited by anti-TGF-β1 and anti-CXCR4 antibody, and the inhibitory effect of anti-CXCR4 antibody was more obvious than that of anti-TGF-β1 antibody. Conclusion: Transforming growth factor-β1 promotes homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury, which will provide useful data on role of TGF-β1 in regulating SDF-1/CXCR4 axis-induced MSCs homing. PMID:26722423

  20. Post-injury administration of allicin attenuates ischemic brain injury through sphingosine kinase 2: In vivo and in vitro studies.

    PubMed

    Lin, Jia-Ji; Chang, Ting; Cai, Wen-Ke; Zhang, Zhuo; Yang, Yong-Xiang; Sun, Chao; Li, Zhu-Yi; Li, Wei-Xin

    2015-10-01

    Allicin, one of the main biologically active compounds derived from garlic, has been shown to exert various pharmacological activities and is considered to have therapeutic potential for many pathologic conditions. In the present study, we investigated the potential post-ischemic neuroprotective effects of allicin and its underlying mechanisms. Using a rat middle cerebral artery occlusion (MCAO) model, we found that intraperitoneal treatment with 50 mg/kg allicin significantly reduced brain infarct volume, attenuated cerebral edema and decreased the neurological deficit score. Allicin treatment also diminished TUNEL positive cells and inhibited the activation of caspase-3 after MCAO. These protective effects could be observed even if the administration was delayed to 6 h after injury. In addition, we evaluated the in vitro protective effects of allicin against oxygen glucose deprivation (OGD) induced neuronal injury in primary cultured cortical neurons. Allicin (50 μM) increased neuronal viability, decreased lactate dehydrogenase (LDH) release and inhibited apoptotic neuronal death after OGD. These protective effects could be observed even if the administration was delayed to 4 h after injury. Furthermore, allicin significantly increased the expression of sphingosine kinases 2 (Sphk2) both in vivo and in vitro. Pretreatment with the Sphk2 inhibitor ABC294640 partially reversed the protective effects of allicin against MCAO and OGD injury, indicating that an Sphk2-mediated mechanism was involved in allicin-induced protection in our models. The combination of findings suggests that post-injury administration of allicin has potential as a neuroprotective strategy for ischemic stroke. PMID:26275594

  1. Acute Neuronal Injury and Blood Genomic Profiles in a Nonhuman Primate Model for Ischemic Stroke

    PubMed Central

    Rodriguez-Mercado, Rafael; Ford, Gregory D; Xu, Zhenfeng; Kraiselburd, Edmundo N; Martinez, Melween I; Eterović, Vesna A; Colon, Edgar; Rodriguez, Idia V; Portilla, Peter; Ferchmin, Pedro A; Gierbolini, Lynette; Rodriguez-Carrasquillo, Maria; Powell, Michael D; Pulliam, John VK; McCraw, Casey O; Gates, Alicia; Ford, Byron D

    2012-01-01

    The goal of this study was to characterize acute neuronal injury in a novel nonhuman primate (NHP) ischemic stroke model by using multiple outcome measures. Silk sutures were inserted into the M1 segment of the middle cerebral artery of rhesus macaques to achieve permanent occlusion of the vessel. The sutures were introduced via the femoral artery by using endovascular microcatheterization techniques. Within hours after middle cerebral artery occlusion (MCAO), infarction was detectable by using diffusion-weighted MRI imaging. The infarcts expanded by 24 h after MCAO and then were detectable on T2-weighted images. The infarcts seen by MRI were consistent with neuronal injury demonstrated histologically. Neurobehavioral function after MCAO was determined by using 2 neurologic testing scales. Neurologic assessments indicated that impairment after ischemia was limited to motor function in the contralateral arm; other neurologic and behavioral parameters were largely unaffected. We also used microarrays to examine gene expression profiles in peripheral blood mononuclear cells after MCAO-induced ischemia. Several genes were altered in a time-dependent manner after MCAO, suggesting that this ischemia model may be suitable for identifying blood biomarkers associated with the presence and severity of ischemia. This NHP stroke model likely will facilitate the elucidation of mechanisms associated with acute neuronal injury after ischemia. In addition, the ability to identify candidate blood biomarkers in NHP after ischemia may prompt the development of new strategies for the diagnosis and treatment of ischemic stroke in humans. PMID:23114047

  2. Multi-parametric imaging of cerebral hemodynamic and metabolic response followed by ischemic injury

    NASA Astrophysics Data System (ADS)

    Qin, Jia; Shi, Lei; Dziennis, Suzan; Wang, Ruikang K.

    2014-02-01

    We use rodent parietal cortex as a model system and utilize a synchronized dual wavelength laser speckle imaging (SDW-LSCI) technique to explore the hemodynamic response of infarct and penumbra to a brain injury (middle cerebral artery occlusion (MCAO) model). The SDW-LSCI system is able to take snapshots rapidly (maximum 500 Hz) over the entire brain surface, providing key information about the hemodynamic response, in terms of which it may be used to elucidate evolution of penumbra region from onsite to 90 min of MCAO. Changes in flow are quantified as to the flow experiencing physical occlusions of the MCA normalized to that of baseline. Furthermore, the system is capable of providing information as to the changes of the concentration of oxygenated, (HbO) deoxygenated (Hb), and total hemoglobin (HbT) in the cortex based on the spectral characteristics of HbO and Hb. We observe that the oxygenation variations in the four regions are detectable and distinct. Combining the useful information, four regions of interest (ROI), infarct, penumbra, reduced flow and contralateral portions in the brain upon ischemic injury may be differentiated. Implications of our results are discussed with respect to current understanding of the mechanisms underlying MCAO. We anticipate that SDW-LSCI holds promise for rapid and large field of view localization of ischemic injury.

  3. Protective effects of flunarizine on ischemic injury in the rat retina.

    PubMed

    Takahashi, K; Lam, T T; Edward, D P; Buchi, E R; Tso, M O

    1992-06-01

    Intracellular calcium overload has been implicated to be a major factor in triggering cell death after ischemic neuronal injury. We investigated the effects of flunarizine hydrochloride, a calcium-overload blocker, on pressure-induced retinal ischemia in a rat model. Retinal ischemia was induced in intraocular pressure to 110 mm Hg for 45 minutes. Two regimens of treatment with flunarizine were examined: (1) prophylactic treatment, in which flunarizine was administered before ischemia and in the early phase of reperfusion; and (2) postischemic treatment, in which flunarizine was administered only in the early phase of reperfusion. Injury was evaluated morphologically and morphometrically by measuring the thickness of the inner retinal layers on plastic-embedded retinal sections and by counting the retinal ganglion cells on retinal flat preparations. By morphologic and morphometric criteria, a significant but partial protection of the inner retinal layers was noted in the groups given either regimen. This protective effect of flunarizine suggests that elevated intracellular calcium concentration may play an important role in ischemic retinal injury. PMID:1596236

  4. Galectin-1-secreting neural stem cells elicit long-term neuroprotection against ischemic brain injury

    PubMed Central

    Wang, Jiayin; Xia, Jinchao; Zhang, Feng; Shi, Yejie; Wu, Yun; Pu, Hongjian; Liou, Anthony K. F.; Leak, Rehana K.; Yu, Xinguang; Chen, Ling; Chen, Jun

    2015-01-01

    Galectin-1 (gal-1), a special lectin with high affinity to β-galactosides, is implicated in protection against ischemic brain injury. The present study investigated transplantation of gal-1-secreting neural stem cell (s-NSC) into ischemic brains and identified the mechanisms underlying protection. To accomplish this goal, secretory gal-1 was stably overexpressed in NE-4C neural stem cells. Transient cerebral ischemia was induced in mice by middle cerebral artery occlusion for 60 minutes and s-NSCs were injected into the striatum and cortex within 2 hours post-ischemia. Brain infarct volume and neurological performance were assessed up to 28 days post-ischemia. s-NSC transplantation reduced infarct volume, improved sensorimotor and cognitive functions, and provided more robust neuroprotection than non-engineered NSCs or gal-1-overexpressing (but non-secreting) NSCs. White matter injury was also ameliorated in s-NSC-treated stroke mice. Gal-1 modulated microglial function in vitro, by attenuating secretion of pro-inflammatory cytokines (TNF-α and nitric oxide) in response to LPS stimulation and enhancing production of anti-inflammatory cytokines (IL-10 and TGF-β). Gal-1 also shifted microglia/macrophage polarization toward the beneficial M2 phenotype in vivo by reducing CD16 expression and increasing CD206 expression. In sum, s-NSC transplantation confers robust neuroprotection against cerebral ischemia, probably by alleviating white matter injury and modulating microglial/macrophage function. PMID:25858671

  5. Melatonin Ameliorates Injury and Specific Responses of Ischemic Striatal Neurons in Rats

    PubMed Central

    Ma, Yuxin; Feng, Qiqi; Ma, Jing; Feng, Zhibo; Zhan, Mali; OuYang, Lisi; Mu, Shuhua; Liu, Bingbing; Jiang, Zhuyi; Jia, Yu; Li, Youlan

    2013-01-01

    Studies have confirmed that middle cerebral artery occlusion (MCAO) causes striatal injury in which oxidative stress is involved in the pathological mechanism. Increasing evidence suggests that melatonin may have a neuroprotective effect on cerebral ischemic damage. This study aimed to examine the morphological changes of different striatal neuron types and the effect of melatonin on striatal injury by MCAO. The results showed that MCAO induced striatum-related dysfunctions of locomotion, coordination, and cognition, which were remarkably relieved with melatonin treatment. MCAO induced severe striatal neuronal apoptosis and loss, which was significantly decreased with melatonin treatment. Within the outer zone of the infarct, the number of Darpp-32+ projection neurons and the densities of dopamine-receptor-1 (D1)+ and dopamine-receptor-2 (D2)+ fibers were reduced; however, both parvalbumin (Parv)+ and choline acetyltransferase (ChAT)+ interneurons were not significantly decreased in number, and neuropeptide Y (NPY)+ and calretinin (Cr)+ interneurons were even increased. With melatonin treatment, the loss of projection neurons and characteristic responses of interneurons were notably attenuated. The present study demonstrates that the projection neurons are rather vulnerable to ischemic damage, whereas the interneurons display resistance and even hyperplasia against injury. In addition, melatonin alleviates striatal dysfunction, neuronal loss, and morphological transformation of interneurons resulting from cerebral ischemia. PMID:23686363

  6. Aging causes collateral rarefaction and increased severity of ischemic injury in multiple tissues

    PubMed Central

    Faber, James E.; Zhang, Hua; Lassance-Soares, Roberta M.; Prabhakar, Pranay; Najafi, Amir H.; Burnett, Mary Susan; Epstein, Stephen E.

    2011-01-01

    Objective Aging is a major risk factor for increased ischemic tissue injury. Whether collateral rarefaction and impaired remodeling contribute to this is unknown. We quantified the number and diameter of native collaterals, and their remodeling in 3-, 16-, 24-, and 31-months-old mice. Methods and Results Aging caused an “age-dose-dependent” greater drop in perfusion immediately after femoral artery ligation, followed by a diminished recovery of flow and increase in tissue injury. These effects were associated with a decline in collateral number, diameter and remodeling. Angiogenesis was also impaired. Mechanistically, these changes were not accompanied by reduced recruitment of T-cells or macrophages to remodeling collaterals. However, eNOS signaling was dysfunctional, as indicated by increased protein nitrosylation and less phosphorylated eNOS and VASP in collateral wall cells. The cerebral circulation exhibited a similar age-dose-dependent loss of collateral number and diameter and increased tortuosity, resulting in an increase in collateral resistance and infarct volume (e.g., 6- and 3-fold, respectively, in 24-months-old mice) after artery occlusion. This was not associated with rarefaction of similarly-sized arterioles. Collateral remodeling was also reduced. Conclusions Our findings demonstrate that aging causes rarefaction and insufficiency of the collateral circulation in multiple tissues, resulting in more severe ischemic tissue injury. PMID:21617137

  7. Eriodictyol-7-O-glucoside activates Nrf2 and protects against cerebral ischemic injury

    SciTech Connect

    Jing, Xu; Ren, Dongmei; Wei, Xinbing; Shi, Huanying; Zhang, Xiumei; Perez, Ruth G.; Lou, Haiyan; Lou, Hongxiang

    2013-12-15

    Stroke is a complex disease that may involve oxidative stress-related pathways in its pathogenesis. The nuclear factor erythroid-2-related factor 2/antioxidant response element (Nrf2/ARE) pathway plays an important role in inducing phase II detoxifying enzymes and antioxidant proteins and thus has been considered a potential target for neuroprotection in stroke. The aim of the present study was to determine whether eriodictyol-7-O-glucoside (E7G), a novel Nrf2 activator, can protect against cerebral ischemic injury and to understand the role of the Nrf2/ARE pathway in neuroprotection. In primary cultured astrocytes, E7G increased the nuclear localization of Nrf2 and induced the expression of the Nrf2/ARE-dependent genes. Exposure of astrocytes to E7G provided protection against oxygen and glucose deprivation (OGD)-induced oxidative insult. The protective effect of E7G was abolished by RNA interference-mediated knockdown of Nrf2 expression. In vivo administration of E7G in a rat model of focal cerebral ischemia significantly reduced the amount of brain damage and ameliorated neurological deficits. These data demonstrate that activation of Nrf2/ARE signaling by E7G is directly associated with its neuroprotection against oxidative stress-induced ischemic injury and suggest that targeting the Nrf2/ARE pathway may be a promising approach for therapeutic intervention in stroke. - Highlights: • E7G activates Nrf2 in astrocytes. • E7G stimulates expression of Nrf2-mediated cytoprotective proteins in astrocytes. • E7G protects astrocytes against OGD-induced cell death and apoptosis. • The neuroprotective effect of E7G involves the Nrf2/ARE pathway. • E7G protects rats against cerebral ischemic injury.

  8. Retinal ischemic injury rescued by sodium 4-phenylbutyrate in a rat model.

    PubMed

    Jeng, Yung-Yue; Lin, Nien-Ting; Chang, Pen-Heng; Huang, Yuan-Ping; Pang, Victor Fei; Liu, Chen-Hsuan; Lin, Chung-Tien

    2007-03-01

    Retinal ischemia is a common cause of visual impairment for humans and animals. Herein, the neuroprotective effects of phenylbutyrate (PBA) upon retinal ischemic injury were investigated using a rat model. Retinal ganglion cells (RGCs) were retrograde labeled with the fluorescent tracer fluorogold (FG) applied to the superior collicoli of test Sprague-Dawley rats. High intraocular pressure and retinal ischemia were induced seven days subsequent to such FG labeling. A dose of either 100 or 400 mg/kg PBA was administered intraperitoneally to test rats at two time points, namely 30 min prior to the induction of retinal ischemia and 1 h subsequent to the cessation of the procedure inducing retinal ischemia. The test-rat retinas were collected seven days subsequent to the induction of retinal ischemia, and densities of surviving RGCs were estimated by counting FG-labeled RGCs within the retina. Histological analysis revealed that ischemic injury caused the loss of retinal RGCs and a net decrease in retinal thickness. For PBA-treated groups, almost 100% of the RGCs were preserved by a pre-ischemia treatment with PBA (at a dose of either 100 or 400 mg/kg), while post-ischemia treatment of RGCs with PBA did not lead to the preservation of RGCs from ischemic injury by PBA as determined by the counting of whole-mount retinas. Pre-ischemia treatment of RGCs with PBA (at a dose of either 100 or 400 mg/kg) significantly reduced the level of ischemia-associated loss of thickness of the total retina, especially the inner retina, and the inner plexiform layer of retina. Besides, PBA treatment significantly reduced the ischemia-induced loss of cells in the ganglion-cell layer of the retina. Taken together, these results suggest that PBA demonstrates a marked neuroprotective effect upon high intraocular pressure-induced retinal ischemia when the PBA is administered prior to ischemia induction. PMID:17178414

  9. Mechanisms of renal repair and survival following acute injury.

    PubMed

    Safirstein, R; DiMari, J; Megyesi, J; Price, P

    1998-09-01

    The reaction of the renal epithelium to injury is heterogenous. Some cells die, others survive apparently intact, while others commit to repair. The determinants of these responses appear to depend on signal transduction pathways and molecular responses that is segment specific and interactive. The kidney, as do cells in culture exposed to various noxious stimuli, react in a typical manner referred to as the stress response. The response is comprised of kinases and their molecular targets as well as cell cycle-specific factors that determine whether a cell survives the injury or not. We propose that this response can be modified by survival factors which upregulate those aspects of the response that are cytoprotective and which downregulate those that are cytoreductive. Preliminary data will be presented to demonstrate the feasibility of this approach. PMID:9754604

  10. The Transcription Factor Interferon Regulatory Factor 1 Is Expressed after Cerebral Ischemia and Contributes to Ischemic Brain Injury

    PubMed Central

    Iadecola, Costantino; Salkowski, Cindy A.; Zhang, Fangyi; Aber, Tracy; Nagayama, Masao; Vogel, Stefanie N.; Elizabeth Ross, M.

    1999-01-01

    The transcription factor interferon regulatory factor 1 (IRF-1) is involved in the molecular mechanisms of inflammation and apoptosis, processes that contribute to ischemic brain injury. In this study, the induction of IRF-1 in response to cerebral ischemia and its role in ischemic brain injury were investigated. IRF-1 gene expression was markedly upregulated within 12 h of occlusion of the middle cerebral artery in C57BL/6 mice. The expression reached a peak 4 d after ischemia (6.0 ± 1.8-fold; P < 0.001) and was restricted to the ischemic regions of the brain. The volume of ischemic injury was reduced by 23 ± 3% in IRF-1+/− and by 46 ± 9% in IRF-1−/− mice (P < 0.05). The reduction in infarct volume was paralleled by a substantial attenuation in neurological deficits. Thus, IRF-1 is the first nuclear transacting factor demonstrated to contribute directly to cerebral ischemic damage and may be a novel therapeutic target in ischemic stroke. PMID:9989987

  11. Treatment with polyamine oxidase inhibitor reduces microglial activation and limits vascular injury in ischemic retinopathy.

    PubMed

    Patel, C; Xu, Z; Shosha, E; Xing, J; Lucas, R; Caldwell, R W; Caldwell, R B; Narayanan, S P

    2016-09-01

    Retinal vascular injury is a major cause of vision impairment in ischemic retinopathies. Insults such as hyperoxia, oxidative stress and inflammation contribute to this pathology. Previously, we showed that hyperoxia-induced retinal neurodegeneration is associated with increased polyamine oxidation. Here, we are studying the involvement of polyamine oxidases in hyperoxia-induced injury and death of retinal vascular endothelial cells. New-born C57BL6/J mice were exposed to hyperoxia (70% O2) from postnatal day (P) 7 to 12 and were treated with the polyamine oxidase inhibitor MDL 72527 or vehicle starting at P6. Mice were sacrificed after different durations of hyperoxia and their retinas were analyzed to determine the effects on vascular injury, microglial cell activation, and inflammatory cytokine profiling. The results of this analysis showed that MDL 72527 treatment significantly reduced hyperoxia-induced retinal vascular injury and enhanced vascular sprouting as compared with the vehicle controls. These protective effects were correlated with significant decreases in microglial activation as well as levels of inflammatory cytokines and chemokines. In order to model the effects of polyamine oxidation in causing microglial activation in vitro, studies were performed using rat brain microvascular endothelial cells treated with conditioned-medium from rat retinal microglia stimulated with hydrogen peroxide. Conditioned-medium from activated microglial cultures induced cell stress signals and cell death in microvascular endothelial cells. These studies demonstrate the involvement of polyamine oxidases in hyperoxia-induced retinal vascular injury and retinal inflammation in ischemic retinopathy, through mechanisms involving cross-talk between endothelial cells and resident retinal microglia. PMID:27239699

  12. Hypothermia inhibits the propagation of acute ischemic injury by inhibiting HMGB1.

    PubMed

    Lee, Jung Ho; Yoon, Eun Jang; Seo, Jeho; Kavoussi, Adriana; Chung, Yong Eun; Chung, Sung Phil; Park, Incheol; Kim, Chul Hoon; You, Je Sung

    2016-01-01

    Acute ischemic stroke causes significant chronic disability worldwide. We designed this study to clarify the mechanism by which hypothermia helps alleviate acute ischemic stroke. In a middle cerebral artery occlusion model (4 h ischemia without reperfusion), hypothermia effectively reduces mean infarct volume. Hypothermia also prevents neurons in the infarct area from releasing high mobility group box 1 (HMGB1), the most well-studied damage-associated molecular pattern protein. By preventing its release, hypothermia also prevents the typical middle cerebral artery occlusion-induced increase in serum HMGB1. We also found that both glycyrrhizin-mediated inhibition of HMGB1 and intracerebroventricular neutralizing antibody treatments before middle cerebral artery occlusion onset diminish infarct volume. This suggests a clear neuroprotective effect of HMGB1 inhibition by hypothermia in the brain. We next used real-time polymerase chain reaction to measure the levels of pro-inflammatory cytokines in peri-infarct regions. Although middle cerebral artery occlusion increases the expression of interleukin-1β and tissue necrosis factor-α, this elevation is suppressed by both hypothermia and glycyrrhizin treatment. We show that hypothermia reduces the production of inflammatory cytokines and helps salvage peri-infarct regions from the propagation of ischemic injury via HMGB1 blockade. In addition to suggesting a potential mechanism for hypothermia's therapeutic effects, our results suggest HMGB1 modulation may lengthen the therapeutic window for stroke treatments. PMID:27544687

  13. Acute kidney injury: Renal disease in the ICU.

    PubMed

    Seller-Pérez, G; Más-Font, S; Pérez-Calvo, C; Villa-Díaz, P; Celaya-López, M; Herrera-Gutiérrez, M E

    2016-01-01

    Acute kidney injury (AKI) in the ICU frequently requires costly supportive therapies, has high morbidity, and its long-term prognosis is not as good as it has been presumed so far. Consequently, AKI generates a significant burden for the healthcare system. The problem is that AKI lacks an effective treatment and the best approach relies on early secondary prevention. Therefore, to facilitate early diagnosis, a broader definition of AKI should be established, and a marker with more sensitivity and early-detection capacity than serum creatinine - the most common marker of AKI - should be identified. Fortunately, new classification systems (RIFLE, AKIN or KDIGO) have been developed to solve these problems, and the discovery of new biomarkers for kidney injury will hopefully change the way we approach renal patients. As a first step, the concept of renal failure has changed from being a "static" disease to being a "dynamic process" that requires continuous evaluation of kidney function adapted to the reality of the ICU patient. PMID:27388683

  14. Renal Impairment with Sublethal Tubular Cell Injury in a Chronic Liver Disease Mouse Model

    PubMed Central

    Ishida, Tokiko; Kotani, Hirokazu; Miyao, Masashi; Kawai, Chihiro; Jemail, Leila; Abiru, Hitoshi; Tamaki, Keiji

    2016-01-01

    The pathogenesis of renal impairment in chronic liver diseases (CLDs) has been primarily studied in the advanced stages of hepatic injury. Meanwhile, the pathology of renal impairment in the early phase of CLDs is poorly understood, and animal models to elucidate its mechanisms are needed. Thus, we investigated whether an existing mouse model of CLD induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) shows renal impairment in the early phase. Renal injury markers, renal histology (including immunohistochemistry for tubular injury markers and transmission electron microscopy), autophagy, and oxidative stress were studied longitudinally in DDC- and standard diet–fed BALB/c mice. Slight but significant renal dysfunction was evident in DDC-fed mice from the early phase. Meanwhile, histological examinations of the kidneys with routine light microscopy did not show definitive morphological findings, and electron microscopic analyses were required to detect limited injuries such as loss of brush border microvilli and mitochondrial deformities. Limited injuries have been recently designated as sublethal tubular cell injury. As humans with renal impairment, either with or without CLD, often show almost normal tubules, sublethal injury has been of particular interest. In this study, the injuries were associated with mitochondrial aberrations and oxidative stress, a possible mechanism for sublethal injury. Intriguingly, two defense mechanisms were associated with this injury that prevent it from progressing to apparent cell death: autophagy and single-cell extrusion with regeneration. Furthermore, the renal impairment of this model progressed to chronic kidney disease with interstitial fibrosis after long-term DDC feeding. These findings indicated that DDC induces renal impairment with sublethal tubular cell injury from the early phase, leading to chronic kidney disease. Importantly, this CLD mouse model could be useful for studying the pathophysiological mechanisms

  15. High-grade renal injuries are often isolated in sports-related trauma

    PubMed Central

    Patel, Darshan P.; Redshaw, Jeffrey D.; Breyer, Benjamin N.; Smith, Thomas G.; Erickson, Bradley A.; Majercik, Sarah D.; Gaither, Thomas W.; Craig, James R.; Gardner, Scott; Presson, Angela P.; Zhang, Chong; Hotaling, James M.; Brant, William O.; Myers, Jeremy B.

    2016-01-01

    Introduction Most high-grade renal injuries (American Association for Surgery of Trauma (AAST) grades III–V) result from motor vehicle collisions associated with numerous concomitant injuries. Sports-related blunt renal injury tends to have a different mechanism, a solitary blow to the flank. We hypothesized that high-grade renal injury is often isolated in sports-related renal trauma. Material and methods We identified patients with AAST grades III–V blunt renal injuries from four level 1 trauma centres across the United States between 1/2005 and 1/2014. Patients were divided into “Sport” or “Non-sport” related groups. Outcomes included rates of hypotension (systolic blood pressure <90 mm Hg), tachycardia (>110 bpm), concomitant abdominal injury, and procedural/surgical intervention between sports and non-sports related injury. Results 320 patients met study criteria. 18% (59) were sports-related injuries with the most common mechanisms being skiing, snowboarding and contact sports (25%, 25%, and 24%, respectively). Median age was 24 years for sports and 30 years for non-sports related renal injuries (p = 0.049). Males were more commonly involved in sports related injuries (85% vs. 72%, p = 0.011). Median injury severity score was lower for sports related injuries (10 vs. 27, p < 0.001). There was no difference in renal abbreviated injury scale scores. Sports related trauma was more likely to be isolated without other significant injury (69% vs. 39% (p < 0.001)). Haemodynamic instability was present in 40% and 51% of sports and non-sports renal injuries (p = 0.30). Sports injuries had lower transfusion (7% vs. 47%, p < 0.001) and lower mortality rates (0% vs. 6%, p = 0.004). There was no difference in renal-specific procedural interventions between the two groups (17% sports vs. 18% non-sports, p = 0.95). Conclusions High-grade sports-related blunt renal trauma is more likely to occur in isolation without other abdominal or thoracic injuries and

  16. A procyanidin type A trimer from cinnamon extract attenuates glial cell swelling and the reduction in glutamate uptake following ischemic injury in vitro

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dietary polyphenols exert neuroprotective effects in ischemic injury. The protective effects of a procyanidin type A trimer (trimer 1) isolated from a water soluble cinnamon extract (CE) were investigated on key features of ischemic injury including cell swelling, increased free radical production, ...

  17. Growth factors for the treatment of ischemic brain injury (growth factor treatment).

    PubMed

    Larpthaveesarp, Amara; Ferriero, Donna M; Gonzalez, Fernando F

    2015-01-01

    In recent years, growth factor therapy has emerged as a potential treatment for ischemic brain injury. The efficacy of therapies that either directly introduce or stimulate local production of growth factors and their receptors in damaged brain tissue has been tested in a multitude of models for different Central Nervous System (CNS) diseases. These growth factors include erythropoietin (EPO), vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), and insulin-like growth factor (IGF-1), among others. Despite the promise shown in animal models, the particular growth factors that should be used to maximize both brain protection and repair, and the therapeutic critical period, are not well defined. We will review current pre-clinical and clinical evidence for growth factor therapies in treating different causes of brain injury, as well as issues to be addressed prior to application in humans. PMID:25942688

  18. [Advance in study on pharmacological mechanisms of Qingkailing injection in intervention of ischemic cerebral injury].

    PubMed

    Chen, Yin-Ying; Wang, Zhong

    2012-11-01

    As a severe threat to human health, ischemic brain injury has a very complex pathological mechanism involving excitotoxic amino acids, oxygen free radical formation, nitric oxide (NO), Ca2+ overload and inflammation. Traditional Chinese medicine Qingkailing injection have shown good clinical efficacy in the treatment of cerebrovascular disease, and thus it is very significant to studies on its pharmacological mechanism. This essay summarizes relevant studies on pharmacological mechanism of a new compound traditional Chinese medicine Jingzhiqiangkailing (JZQKL) injection in treatment on cerebral ischemia, and explains the pharmacological mechanism of its single effective compounds and their compatibility in treatment of schemic brain injury in the aspects of regulating inflammatory response, neurotrophic factors, vascular protection, blood-brain barrier (BBB) protection and others, and thus providing information for further studies. PMID:23397712

  19. Salusins protect myocardium against ischemic injury by alleviating endoplasmic reticulum stress.

    PubMed

    Wang, Jianfei; Wang, Yin; Shan, Shifu; Hu, Tiantian; Chen, Huyan; Tian, Jing; Ren, Anjing; Zhou, Xu; Yuan, Wenjun; Lin, Li

    2012-04-01

    Salusins are regulatory peptides that affect cardiovascular function. We previously reported that salusin-α and -β protected cultured cardiomyocytes from serum deprivation-induced cell death through upregulating glucose-regulated protein 78 (GRP78), an endoplasmic reticulum (ER) resident protein whose overexpression acts as a marker and suppressor of ER stress. The present study examined whether salusin-α and -β inhibit ER stress in ischemic myocardium. In a rat model of myocardial infarction created by ligating the left anterior descending coronary artery (LAD), salusin-α or -β was intravenously injected at 5 or 15 nmol kg(-1) 15 min prior to 2 h of LAD occlusion. The high dose of salusin-α and -β significantly improved heart function and hemodynamics in LAD-occluded rats, but had no effects in sham-operated rats. The arrhythmias caused by LAD occlusion were markedly attenuated by salusin-α and -β. The apoptotic rate in ischemic myocardium was reduced from 31.5%±3.7% to 19.8%±2.2% and 12.3%±2.2%, and the infarct size was reduced from 53.4%±4.0% of the risk area to 26.5%±9.7% and 23.7%±8.9% by 15 nmol kg(-1) salusin-α and -β, respectively. Furthermore, salusin-α and -β prevented the activation of GRP78 and ER stress-specific apoptotic effectors caspase-12 and CHOP (C/EBP homologous protein), and attenuated the reduction of an ER stress-associated antiapoptotic protein Bcl-2 in ischemic cardiac tissue. The salusins also inhibited the ER stress induced by tunicamycin in cultured rat H9c2 cardiomyocytes. These results indicate that salusins protect myocardium against ischemic injury by inhibiting ER stress and ER stress-associated apoptosis. PMID:22566093

  20. Protection from ischemic heart injury by a vigilant heme oxygenase-1 plasmid system.

    PubMed

    Tang, Yao Liang; Tang, Yi; Zhang, Y Clare; Qian, Keping; Shen, Leping; Phillips, M Ian

    2004-04-01

    Although human heme oxygenase-1 (hHO-1) could provide a useful approach for cellular protection in the ischemic heart, constitutive overexpression of hHO-1 may lead to unwanted side effects. To avoid this, we designed a hypoxia-regulated hHO-1 gene therapy system that can be switched on and off. This vigilant plasmid system is composed of myosin light chain-2v promoter and a gene switch that is based on an oxygen-dependent degradation domain from the hypoxia inducible factor-1-alpha. The vector can sense ischemia and switch on the hHO-1 gene system, specifically in the heart. In an in vivo experiment, the vigilant hHO-1 plasmid or saline was injected intramyocardially into myocardial infarction mice or sham operation mice. After gene transfer, expression of hHO-1 was only detected in the ischemic heart treated with vigilant hHO-1 plasmids. Masson trichrome staining showed significantly fewer fibrotic areas in vigilant hHO-1 plasmids-treated mice compared with saline control (43.0%+/-4.8% versus 62.5%+/-3.3%, P<0.01). The reduction of interstitial fibrosis is accompanied by an increase in myocardial hHO-1 expression in peri-infarct border areas, concomitant with higher Bcl-2 levels and lower Bax, Bak, and caspase 3 levels in the ischemic myocardium compared with saline control. By use of a cardiac catheter, heart from vigilant hHO-1 plasmids-treated mice showed improved recovery of contractile and diastolic performance after myocardial infarction compared with saline control. This study documents the beneficial regulation and therapeutic potential of vigilant plasmid-mediated hHO-1 gene transfer. This novel gene transfer strategy can provide cardiac-specific protection from future repeated bouts of ischemic injury. PMID:14981066

  1. Interleukin-17A Regulates Renal Sodium Transporters and Renal Injury in Angiotensin II-Induced Hypertension.

    PubMed

    Norlander, Allison E; Saleh, Mohamed A; Kamat, Nikhil V; Ko, Benjamin; Gnecco, Juan; Zhu, Linjue; Dale, Bethany L; Iwakura, Yoichiro; Hoover, Robert S; McDonough, Alicia A; Madhur, Meena S

    2016-07-01

    Angiotensin II-induced hypertension is associated with an increase in T-cell production of interleukin-17A (IL-17A). Recently, we reported that IL-17A(-/-) mice exhibit blunted hypertension, preserved natriuresis in response to a saline challenge, and decreased renal sodium hydrogen exchanger 3 expression after 2 weeks of angiotensin II infusion compared with wild-type mice. In the current study, we performed renal transporter profiling in mice deficient in IL-17A or the related isoform, IL-17F, after 4 weeks of Ang II infusion, the time when the blood pressure reduction in IL-17A(-/-) mice is most prominent. Deficiency of IL-17A abolished the activation of distal tubule transporters, specifically the sodium-chloride cotransporter and the epithelial sodium channel and protected mice from glomerular and tubular injury. In human proximal tubule (HK-2) cells, IL-17A increased sodium hydrogen exchanger 3 expression through a serum and glucocorticoid-regulated kinase 1-dependent pathway. In mouse distal convoluted tubule cells, IL-17A increased sodium-chloride cotransporter activity in a serum and glucocorticoid-regulated kinase 1/Nedd4-2-dependent pathway. In both cell types, acute treatment with IL-17A induced phosphorylation of serum and glucocorticoid-regulated kinase 1 at serine 78, and treatment with a serum and glucocorticoid-regulated kinase 1 inhibitor blocked the effects of IL-17A on sodium hydrogen exchanger 3 and sodium-chloride cotransporter. Interestingly, both HK-2 and mouse distal convoluted tubule 15 cells produce endogenous IL-17A. IL17F had little or no effect on blood pressure or renal sodium transporter abundance. These studies provide a mechanistic link by which IL-17A modulates renal sodium transport and suggest that IL-17A inhibition may improve renal function in hypertension and other autoimmune disorders. PMID:27141060

  2. Mutant Erythropoietin without Erythropoietic Activity is Neuroprotective against Ischemic Brain Injury

    PubMed Central

    Gan, Yu; Xing, Juan; Jing, Zheng; Stetler, R. Anne; Zhang, Feng; Luo, Yumin; Ji, Xunmin; Gao, Yanqin; Cao, Guodong

    2012-01-01

    Background and Purpose Erythropoietin (EPO) confers potent neuroprotection against ischemic injury. However, treatment for stroke requires high doses and multiple administrations of EPO, which may cause deleterious side effects due to its erythropoietic activity. This study identifies a novel non-erythropoietic mutant EPO (MEPO) and investigates its potential neuroprotective effects and underlying mechanism in animal model of cerebral ischemia. Methods We constructed a series of MEPOs, each containing a single amino acid mutation within the erythropoietic motif, and tested their erythropoietic activity. Using cortical neuronal cultures exposed to NMDA neurotoxicity and a murine model of transient middle cerebral artery occlusion (MCAO), neuroprotection and neurofunctional outcomes were assessed as well as activation of intracellular signaling pathways. Results The serine to isoleucine mutation at position 104 (S104I-EPO) completely abolished the erythropoietic and platelet-stimulating activity of EPO. Administration of S104I-EPO significantly inhibited NMDA-induced neuronal death in primary cultures, and protected against cerebral infarction and neurological deficits with an efficacy similar to that of wild-type EPO. Both S104I-EPO and wild-type EPO activated similar pro-survival signaling pathways, such as PI3K/AKT, MAPK/ERK1/2 and STAT5. Inhibition of PI3K/AKT or MAPK/ERK1/2 signaling pathways significantly attenuated the neuroprotective effects of S104I-EPO, indicating that activation of these pathways underlies the neuroprotective mechanism of MEPO against cerebral ischemia. Conclusions S104I-EPO confers neuroprotective effects comparable to those of wild-type EPO against ischemic brain injury, with the added benefit of lacking erythropoietic and platelet-stimulating side effects. Our novel findings suggest that the non-erythropoietic mutant EPO is a legitimate candidate for ischemic stroke intervention. PMID:22984011

  3. Sex-dependent effects of chronic psychosocial stress on myocardial sensitivity to ischemic injury.

    PubMed

    Rorabaugh, Boyd R; Krivenko, Anna; Eisenmann, Eric D; Bui, Albert D; Seeley, Sarah; Fry, Megan E; Lawson, Joseph D; Stoner, Lauren E; Johnson, Brandon L; Zoladz, Phillip R

    2015-01-01

    Individuals with post-traumatic stress disorder (PTSD) experience many debilitating symptoms, including intrusive memories, persistent anxiety and avoidance of trauma-related cues. PTSD also results in numerous physiological complications, including increased risk for cardiovascular disease (CVD). However, characterization of PTSD-induced cardiovascular alterations is lacking, especially in preclinical models of the disorder. Thus, we examined the impact of a psychosocial predator-based animal model of PTSD on myocardial sensitivity to ischemic injury. Male and female Sprague-Dawley rats were exposed to psychosocial stress or control conditions for 31 days. Stressed rats were given two cat exposures, separated by a period of 10 days, and were subjected to daily social instability throughout the paradigm. Control rats were handled daily for the duration of the experiment. Rats were tested on the elevated plus maze (EPM) on day 32, and hearts were isolated on day 33 and subjected to 20 min ischemia and 2 h reperfusion on a Langendorff isolated heart system. Stressed male and female rats gained less body weight relative to controls, but only stressed males exhibited increased anxiety on the EPM. Male, but not female, rats exposed to psychosocial stress exhibited significantly larger infarcts and attenuated post-ischemic recovery of contractile function compared to controls. Our data demonstrate that predator stress combined with daily social instability sex-dependently increases myocardial sensitivity to ischemic injury. Thus, this manipulation may be useful for studying potential mechanisms underlying cardiovascular alterations in PTSD, as well as sex differences in the cardiovascular stress response. PMID:26458179

  4. Ischemic preconditioning protects the brain against injury via inhibiting CaMKII-nNOS signaling pathway.

    PubMed

    Wang, Mei; Qi, Da-Shi; Zhou, Cui; Han, Dong; Li, Pei-Pei; Zhang, Fang; Zhou, Xiao-Yan; Han, Meng; Di, Jie-Hui; Ye, Jun-Song; Yu, Hong-Min; Song, Yuan-Jian; Zhang, Guang-Yi

    2016-03-01

    Although studies have shown that cerebral ischemic preconditioning (IPC) can ameliorate ischemia/reperfusion (I/R) induced brain damage, but its precise mechanisms remain unknown. Therefore, the aim of this study was to investigate the neuroprotective mechanisms of IPC against ischemic brain damage induced by cerebral I/R and to explore whether the Calcium/calmodulin-dependent protein kinase II (CaMKII)-mediated up-regulation of nNOS ser847-phosphorylation signaling pathway contributed to the protection provided by IPC. Transient global brain ischemia was induced by 4-vessel occlusion in adult male Sprague-Dawley rats. The rats were pretreated with 3min of IPC alone or KN62 (selective antagonist of CaMKII) treatment before IPC, after reperfusion for 3 days, 6min ischemia was induced. Cresyl violet staining was used to examine the survival of hippocampal CA1 pyramidal neurons. Immunoblotting was performed to measure the phosphorylation of CaMKII, nNOS, c-Jun and the expression of FasL. Immunoprecipitation was used to examine the binding between PSD95 and nNOS. The results showed that IPC could significantly protect neurons against cerebral I/R injury, furthermore, the combination of PSD95 and nNOS was increased, coinstantaneously the phosphorylation of CaMKII and nNOS (ser847) were up-regulated, however the activation of c-Jun and FasL were reduced. Conversely, KN62 treatment before IPC reversed all these effects of IPC. Taken together, the results suggest that IPC could diminish ischemic brain injury through CaMKII-mediated up-regulation of nNOS ser847-phosphorylation signaling pathway. PMID:26794251

  5. Therapeutic Impact of Follistatin-Like 1 on Myocardial Ischemic Injury in Preclinical Models

    PubMed Central

    Ogura, Yasuhiro; Ouchi, Noriyuki; Ohashi, Koji; Shibata, Rei; Kataoka, Yoshiyuki; Kambara, Takahiro; Kito, Tetsutaro; Maruyama, Sonomi; Yuasa, Daisuke; Matsuo, Kazuhiro; Enomoto, Takashi; Uemura, Yusuke; Miyabe, Megumi; Ishii, Masakazu; Yamamoto, Takashi; Shimizu, Yuuki; Walsh, Kenneth; Murohara, Toyoaki

    2012-01-01

    Background Acute coronary syndrome is a leading cause of death in developed countries. Follistatin-like 1 (FSTL1) is a myocyte-derived secreted protein that is upregulated in the heart in response to ischemic insult. Here, we investigated the therapeutic impact of FSTL1 on acute cardiac injury in small and large preclinical animal models of ischemia/reperfusion and dissected its molecular mechanism. Methods and Results Administration of human FSTL1 protein significantly attenuated myocardial infarct size in a mouse or pig model of ischemia/reperfusion, which was associated with a reduction of apoptosis and inflammatory responses in the ischemic heart. Administration of FSTL1 enhanced the phosphorylation of AMP-activated protein kinase in the ischemia/reperfusion–injured heart. In cultured cardiac myocytes, FSTL1 suppressed apoptosis in response to hypoxia/reoxygenation and lipopolysaccharide-stimulated expression of proinflammatory genes through its ability to activate AMP-activated protein kinase. Ischemia/reperfusion led to enhancement of bone morphogenetic protein-4 expression and Smad1/5/8 phosphorylation in the heart, and FSTL1 suppressed the increased phosphorylation of Smad1/5/8 in ischemic myocardium. Treating cardiac myocytes with FSTL1 abolished the bone morphogenetic protein-4 –stimulated increase in apoptosis, Smad1/5/8 phosphorylation, and proinflammatory gene expression. In cultured macrophages, FSTL1 diminished lipopolysaccharide-stimulated expression of proinflammatory genes via activation of AMP-activated protein kinase and abolished bone morphogenetic protein-4 – dependent induction of proinflammatory mediators. Conclusions Our data indicate that FSTL1 can prevent myocardial ischemia/reperfusion injury by inhibiting apoptosis and inflammatory response through modulation of AMP-activated protein kinase– and bone morphogenetic protein-4 – dependent mechanisms, suggesting that FSTL1 could represent a novel therapeutic target for post

  6. Resveratrol attenuates peripheral and brain inflammation and reduces ischemic brain injury in aged female mice.

    PubMed

    Jeong, Sae Im; Shin, Jin A; Cho, Sunghee; Kim, Hye Won; Lee, Ji Yoon; Kang, Jihee Lee; Park, Eun-Mi

    2016-08-01

    Resveratrol is known to improve metabolic dysfunction associated with obesity. Visceral obesity is a sign of aging and is considered a risk factor for ischemic stroke. In this study, we investigated the effects of resveratrol on inflammation in visceral adipose tissue and the brain and its effects on ischemic brain injury in aged female mice. Mice treated with resveratrol (0.1 mg/kg, p.o.) for 10 days showed reduced levels of interleukin-1β and tumor necrosis factor-α, as well as a reduction in the size of adipocytes in visceral adipose tissue. Resveratrol also reduced interleukin-1β and tumor necrosis factor-α protein levels and immunoglobulin G extravasation in the brain. Mice treated with resveratrol demonstrated smaller infarct size, improved neurological function, and blunted peripheral inflammation at 3 days postischemic stroke. These results showed that resveratrol counteracted inflammation in visceral adipose tissue and in the brain and reduced stroke-induced brain injury and peripheral inflammation in aged female mice. Therefore, resveratrol administration can be a valuable strategy for the prevention of age-associated and disease-provoked inflammation in postmenopausal women. PMID:27318135

  7. Ischemic post-conditioning to counteract intestinal ischemia/reperfusion injury

    PubMed Central

    Guan, Yan-Fang; Pritts, Timothy A; Montrose, Marshall H

    2010-01-01

    Intestinal ischemia is a severe disorder with a variety of causes. Reperfusion is a common occurrence during treatment of acute intestinal ischemia but the injury resulting from ischemia/reperfusion (IR) may lead to even more serious complications from intestinal atrophy to multiple organ failure and death. The susceptibility of the intestine to IR-induced injury (IRI) appears from various experimental studies and clinical settings such as cardiac and major vascular surgery and organ transplantation. Whereas oxygen free radicals, activation of leukocytes, failure of microvascular perfusion, cellular acidosis and disturbance of intracellular homeostasis have been implicated as important factors in the pathogenesis of intestinal IRI, the mechanisms underlying this disorder are not well known. To date, increasing attention is being paid in animal studies to potential pre- and post-ischemia treatments that protect against intestinal IRI such as drug interference with IR-induced apoptosis and inflammation processes and ischemic pre-conditioning. However, better insight is needed into the molecular and cellular events associated with reperfusion-induced damage to develop effective clinical protection protocols to combat this disorder. In this respect, the use of ischemic post-conditioning in combination with experimentally prolonged acidosis blocking deleterious reperfusion actions may turn out to have particular clinical relevance. PMID:21607154

  8. CITED4 induces physiologic hypertrophy and promotes functional recovery after ischemic injury

    PubMed Central

    Bezzerides, Vassilios J.; Platt, Colin; Lerchenmüller, Carolin; Paruchuri, Kaavya; Oh, Nul Loren; Xiao, Chunyang; Cao, Yunshan; Mann, Nina; Spiegelman, Bruce M.; Rosenzweig, Anthony

    2016-01-01

    The mechanisms by which exercise mediates its multiple cardiac benefits are only partly understood. Prior comprehensive analyses of the cardiac transcriptional components and microRNAs dynamically regulated by exercise suggest that the CBP/p300-interacting protein CITED4 is a downstream effector in both networks. While CITED4 has documented functional consequences in neonatal cardiomyocytes in vitro, nothing is known about its effects in the adult heart. To investigate the impact of cardiac CITED4 expression in adult animals, we generated transgenic mice with regulated, cardiomyocyte-specific CITED4 expression. Cardiac CITED4 expression in adult mice was sufficient to induce an increase in heart weight and cardiomyocyte size with normal systolic function, similar to the effects of endurance exercise training. After ischemia-reperfusion, CITED4 expression did not change initial infarct size but mediated substantial functional recovery while reducing ventricular dilation and fibrosis. Forced cardiac expression of CITED4 also induced robust activation of the mTORC1 pathway after ischemic injury. Moreover, pharmacological inhibition of mTORC1 abrogated CITED4’s effects in vitro and in vivo. Together, these data establish CITED4 as a regulator of mTOR signaling that is sufficient to induce physiologic hypertrophy at baseline and mitigate adverse ventricular remodeling after ischemic injury. PMID:27430023

  9. Lipopolysaccharide Pretreatment Protects from Renal Ischemia/Reperfusion Injury

    PubMed Central

    Heemann, Uwe; Szabo, Attila; Hamar, Peter; Müller, Veronika; Witzke, Oliver; Lutz, Jens; Philipp, Thomas

    2000-01-01

    In vivo administration of low doses of lipopolysaccharide (LPS) to rodents can protect these animals from subsequently administrated, usually lethal doses of endotoxin or LPS. In this study we tested the effects of LPS pretreatment on ischemia/reperfusion injury in the kidney. Male C57/B1 mice were pretreated with different doses of LPS or phosphate-buffered saline on days −4 and −3. The right kidney was removed, and the vessels of the left kidney were clamped for 30 or 45 minutes on day 0. Creatinine levels and survival of animals were monitored. To test the involvement of cytokines, additional animals were harvested before (“time 0”) and 15 minutes, 1, 2, 8, and 16 hours after reperfusion for histology, immunohistochemistry, terminal deoxynucleotidyltransferase-mediated UTP end-labeling assay, and reverse transcriptase-polymerase chain reaction analysis (including tumor necrosis factor (TNF)-α, interleukin (IL)-1, IL-6, inducible nitric oxide synthase (iNOS), and interferon (IFN)-γ messenger RNA (mRNA)). In controls, renal ischemia of 30 minutes was nonlethal, whereas 73% of the animals died within 48 ± 18 hours, after 45 minutes of ischemia. All different doses of LPS protected the animals from lethal renal ischemia/reperfusion injury. Starting at similar levels, serum creatinine increased significantly in controls but not in LPS-pretreated animals over time. As early as 2 hours after reperfusion, tubular cell damage was significantly more pronounced in controls than in LPS-treated mice. In controls, tubules deteriorated progressively until 8 hours of reperfusion. At this time, more than 50% of tubular cells were destroyed. This destruction was accompanied by a pronounced leukocytic infiltration, predominantly by macrophages. In contrast, LPS pretreatment prevented the destruction of kidney tissue and infiltration by leukocytes. The terminal deoxynucleotidyltransferase-mediated UTP end-labeling assay revealed significantly more apoptotic cells in

  10. Proton-sensitive cation channels and ion exchangers in ischemic brain injury: new therapeutic targets for stroke?

    PubMed Central

    Leng, Tiandong; Shi, Yejie; Xiong, Zhi-Gang; Sun, Dandan

    2014-01-01

    Ischemic brain injury results from complicated cellular mechanisms. The present therapy for acute ischemic stroke is limited to thrombolysis with the recombinant tissue plasminogen activator (rtPA) and mechanical recanalization. Therefore, a better understanding of ischemic brain injury is needed for the development of more effective therapies. Disruption of ionic homeostasis plays an important role in cell death following cerebral ischemia. Glutamate receptor-mediated ionic imbalance and neurotoxicity have been well established in cerebral ischemia after stroke. However, non-NMDA receptor-dependent mechanisms, involving acid-sensing ion channel 1a (ASIC1a), transient receptor potential melastatin 7 (TRPM7), and Na+/H+ exchanger isoform 1 (NHE1), have recently emerged as important players in the dysregulation of ionic homeostasis in the CNS under ischemic conditions. These H+-sensitive channels and/or exchangers are expressed in the majority of cell types of the neurovascular unit. Sustained activation of these proteins causes excessive influx of cations, such as Ca2+, Na+, and Zn2+, and leads to ischemic reperfusion brain injury. In this review, we summarize recent pre-clinical experimental research findings on how these channels/exchangers are regulated in both in vitro and in vivo models of cerebral ischemia. The blockade or transgenic knockdown of these proteins was shown to be neuroprotective in these ischemia models. Taken together, these non-NMDA receptor-dependent mechanisms may serve as novel therapeutic targets for stroke intervention. PMID:24467911

  11. Simvastatin Reduces Lipopolysaccharides-Accelerated Cerebral Ischemic Injury via Inhibition of Nuclear Factor-kappa B Activity.

    PubMed

    Anthony Jalin, Angela M A; Lee, Jae-Chul; Cho, Geum-Sil; Kim, Chunsook; Ju, Chung; Pahk, Kisoo; Song, Hwa Young; Kim, Won-Ki

    2015-11-01

    Preceding infection or inflammation such as bacterial meningitis has been associated with poor outcomes after stroke. Previously, we reported that intracorpus callosum microinjection of lipopolysaccharides (LPS) strongly accelerated the ischemia/reperfusion-evoked brain tissue damage via recruiting inflammatory cells into the ischemic lesion. Simvastatin, 3-hydroxy-3-methylgultaryl (HMG)-CoA reductase inhibitor, has been shown to reduce inflammatory responses in vascular diseases. Thus, we investigated whether simvastatin could reduce the LPS-accelerated ischemic injury. Simvastatin (20 mg/kg) was orally administered to rats prior to cerebral ischemic insults (4 times at 72, 48, 25, and 1-h pre-ischemia). LPS was microinjected into rat corpus callosum 1 day before the ischemic injury. Treatment of simvastatin reduced the LPS-accelerated infarct size by 73%, and decreased the ischemia/reperfusion-induced expressions of pro-inflammatory mediators such as iNOS, COX-2 and IL-1β in LPS-injected rat brains. However, simvastatin did not reduce the infiltration of microglial/macrophageal cells into the LPS-pretreated brain lesion. In vitro migration assay also showed that simvastatin did not inhibit the monocyte chemoattractant protein-1-evoked migration of microglial/macrophageal cells. Instead, simvastatin inhibited the nuclear translocation of NF-κB, a key signaling event in expressions of various proinflammatory mediators, by decreasing the degradation of IκB. The present results indicate that simvastatin may be beneficial particularly to the accelerated cerebral ischemic injury under inflammatory or infectious conditions. PMID:26535078

  12. Nature of the renal injury following total renal ischemia in man.

    PubMed Central

    Myers, B D; Miller, D C; Mehigan, J T; Olcott, C O; Golbetz, H; Robertson, C R; Derby, G; Spencer, R; Friedman, S

    1984-01-01

    The effects of total renal ischemia (TRI) of 15-87 min duration due to suprarenal clamping of the aorta were studied in 15 mannitol-treated patients undergoing abdominal aortic surgery. 15 patients undergoing similar surgery but requiring only infrarenal clamping served as controls. 1-2 h following TRI, GFR was reduced to only 39% of that in controls, 23 +/- 5 vs. 59 +/- 7 ml/min (P less than 0.001). This could not be ascribed to impaired renal plasma flow (RPF), which was mildly reduced to 331 +/- 71 and was not different from the value in controls, 407 +/- 66 ml/min. However, impaired PAH extraction (43 +/- 7%) and isosthenuria, not present in controls, suggest a primary role for tubular injury in lowering GFR at this time. 24 h following TRI, the GFR remained depressed below controls, 45 +/- 8 vs. 84 +/- 8 ml/min (P less than 0.005), while the transglomerular sieving of neutral dextrans was significantly enhanced (radius interval, 24-40 A). A theoretical analysis of transcapillary solute exchange revealed that these findings could be largely explained by a selective reduction of either RPF (-61%) or of transmembrane hydraulic pressure difference (-18%) below control values. Alternately, a combination of these two factors with changes of smaller magnitude could explain the findings. In contrast, a selective increase in oncotic pressure or decrease of the glomerular ultrafiltration coefficient could be excluded as a cause of hypofiltration 24 h after TRI. These observations lead us to suggest that the transient azotemia observed following TRI is due to a self-limited injury to the nephron that is identical to that seen in overt and sustained forms of acute renal failure. PMID:6421876

  13. Pathophysiology and Treatments of Oxidative Injury in Ischemic Stroke: Focus on the Phagocytic NADPH Oxidase 2

    PubMed Central

    Carbone, Federico; Teixeira, Priscila Camillo; Braunersreuther, Vincent; Mach, François; Vuilleumier, Nicolas

    2015-01-01

    Abstract Significance: Phagocytes play a key role in promoting the oxidative stress after ischemic stroke occurrence. The phagocytic NADPH oxidase (NOX) 2 is a membrane-bound enzyme complex involved in the antimicrobial respiratory burst and free radical production in these cells. Recent Advances: Different oxidants have been shown to induce opposite effects on neuronal homeostasis after a stroke. However, several experimental models support the detrimental effects of NOX activity (especially the phagocytic isoform) on brain recovery after stroke. Therapeutic strategies selectively targeting the neurotoxic ROS and increasing neuroprotective oxidants have recently produced promising results. Critical Issues: NOX2 might promote carotid plaque rupture and stroke occurrence. In addition, NOX2-derived reactive oxygen species (ROS) released by resident and recruited phagocytes enhance cerebral ischemic injury, activating the inflammatory apoptotic pathways. The aim of this review is to update evidence on phagocyte-related oxidative stress, focusing on the role of NOX2 as a potential therapeutic target to reduce ROS-related cerebral injury after stroke. Future Directions: Radical scavenger compounds (such as Ebselen and Edaravone) are under clinical investigation as a therapeutic approach against stroke. On the other hand, NOX inhibition might represent a promising strategy to prevent the stroke-related injury. Although selective NOX inhibitors are not yet available, nonselective compounds (such as apocynin and fasudil) provided encouraging results in preclinical studies. Whereas additional studies are needed to better evaluate this therapeutic potential in human beings, the development of specific NOX inhibitors (such as monoclonal antibodies, small-molecule inhibitors, or aptamers) might further improve brain recovery after stroke. Antioxid. Redox Signal. 23, 460–489. PMID:24635113

  14. Human Kidney Injury Molecule-1 Is a Tissue and Urinary Tumor Marker of Renal Cell Carcinoma

    PubMed Central

    Han, Won K.; Alinani, Anwar; Wu, Chin-Lee; Michaelson, Dror; Loda, Massimo; McGovern, Francis J.; Thadhani, Ravi; Bonventre, Joseph V.

    2005-01-01

    Human kidney injury molecule-1 (hKIM-1) is a type 1 transmembrane protein that is not detectable in normal kidney tissue but is expressed at high levels in human and rodent kidneys with dedifferentiated proximal tubule epithelial cells after ischemic or toxic injury. Therefore, it was hypothesized that renal tumors express hKIM-1 and release this protein into the urine. Forty renal cell carcinoma (RCC) and 484 nonrenal tumors were analyzed by immunohistochemistry for expression of hKIM-1 (group 1). Urine samples before nephrectomy and nephrectomy tissue samples were collected from an additional 42 patients with renal tumors, from 30 normal control subjects, and also from 10 patients with prostate carcinoma (group 2). In five additional patients with RCC, urine was collected before and after nephrectomy (group 3). Tissue was examined for expression of hKIM-1, and cell-free urine supernatants were analyzed for hKIM-1 by ELISA. Urinary hKIM-1 was normalized to the urinary creatinine concentration (UCr). Expression of hKIM-1 was present in 32 tissue sections (91%) of 35 clear cell RCC (group 1). In group 2, the normalized urinary hKIM-1 levels were significantly higher in patients with clear cell RCC (0.39 ± 0.08 ng/mg UCr; n = 21), compared with levels in patients with prostate carcinoma (0.12 ± 0.03 ng/mg UCr; P < 0.02; n = 10), or normal control subjects (0.05 ± 0.01 ng/mg UCr; P < 0.005; n = 30). Tissue sections from 28 (82%) of 34 primary RCC stained positively for the expression of hKIM-1. In all patients with a detectable prenephrectomy urinary hKIM-1 level, there was either complete disappearance or marked reduction after nephrectomy (group 3). In conclusion, the cleaved ectodomain of hKIM-1 can be detected in the urine of patients with RCC and may serve as a new biomarker for early detection of RCC. PMID:15744000

  15. Brimonidine Blocks Glutamate Excitotoxicity-Induced Oxidative Stress and Preserves Mitochondrial Transcription Factor A in Ischemic Retinal Injury

    PubMed Central

    Lee, Dongwook; Kim, Keun-Young; Noh, You Hyun; Chai, Stephen; Lindsey, James D.; Ellisman, Mark H.; Weinreb, Robert N.; Ju, Won-Kyu

    2012-01-01

    Glutamate excitotoxicity-induced oxidative stress have been linked to mitochondrial dysfunction in retinal ischemia and optic neuropathies including glaucoma. Brimonindine (BMD), an alpha 2-adrenergic receptor agonist, contributes to the neuroprotection of retinal ganglion cells (RGCs) against glutamate excitotoxicity or oxidative stress. However, the molecular mechanisms of BMD-associated mitochondrial preservation in RGC protection against glutamate excitotoxicity-induced oxidative stress following retinal ischemic injury remain largely unknown. Here, we tested whether activation of alpha 2 adrenergic receptor by systemic BMD treatment blocks glutamate excitotoxicity-induced oxidative stress, and preserves the expression of mitochondrial transcription factor A (Tfam) and oxidative phosphorylation (OXPHOS) complex in ischemic retina. Sprague-Dawley rats received BMD (1 mg/kg/day) or vehicle (0.9% saline) systemically and then transient ischemia was induced by acute intraocular pressure elevation. Systemic BMD treatment significantly increased RGC survival at 4 weeks after ischemia. At 24 hours, BMD significantly decreased Bax expression but increased Bcl-xL and phosphorylated Bad protein expression in ischemic retina. Importantly. BMD significantly blocked the upregulations of N-methyl-D-aspartate receptors 1 and 2A protein expression, as well as of SOD2 protein expression in ischemic retina at 24 hours. During the early neurodegeneration following ischemic injury (12–72 hours), Tfam and OXPHOS complex protein expression were significantly increased in vehicle-treated retina. At 24 hours after ischemia, Tfam immunoreactivity was increased in the outer plexiform layer, inner nuclear layer, inner plexiform layer and ganglion cell layer. Further, Tfam protein was expressed predominantly in RGCs. Finally, BMD preserved Tfam immunoreactivity in RGCs as well as Tfam/OXPHOS complex protein expression in the retinal extracts against ischemic injury. Our findings suggest

  16. Astragaloside IV ameliorates renal injury in db/db mice.

    PubMed

    Sun, Huili; Wang, Wenjing; Han, Pengxun; Shao, Mumin; Song, Gaofeng; Du, Heng; Yi, Tiegang; Li, Shunmin

    2016-01-01

    Diabetic nephropathy is a lethal complication of diabetes mellitus and a major type of chronic kidney disease. Dysregulation of the Akt pathway and its downstream cascades, including mTOR, NFκB, and Erk1/2, play a critical role in the development of diabetic nephropathy. Astragaloside IV is a major component of Huangqi and exerts renal protection in a mouse model of type 1 diabetes. The current study was undertaken to investigate the protective effects of diet supplementation of AS-IV on renal injury in db/db mice, a type 2 diabetic mouse model. Results showed that administration of AS-IV reduced albuminuria, ameliorated changes in the glomerular and tubular pathology, and decreased urinary NAG, NGAL, and TGF-β1 in db/db mice. AS-IV also attenuated the diabetes-related activation of Akt/mTOR, NFκB, and Erk1/2 signaling pathways without causing any detectable hepatotoxicity. Collectively, these findings showed AS-IV to be beneficial to type 2 diabetic nephropathy, which might be associated with the inhibition of Akt/mTOR, NFκB and Erk1/2 signaling pathways. PMID:27585918

  17. Astragaloside IV ameliorates renal injury in db/db mice

    PubMed Central

    Sun, Huili; Wang, Wenjing; Han, Pengxun; Shao, Mumin; Song, Gaofeng; Du, Heng; Yi, Tiegang; Li, Shunmin

    2016-01-01

    Diabetic nephropathy is a lethal complication of diabetes mellitus and a major type of chronic kidney disease. Dysregulation of the Akt pathway and its downstream cascades, including mTOR, NFκB, and Erk1/2, play a critical role in the development of diabetic nephropathy. Astragaloside IV is a major component of Huangqi and exerts renal protection in a mouse model of type 1 diabetes. The current study was undertaken to investigate the protective effects of diet supplementation of AS-IV on renal injury in db/db mice, a type 2 diabetic mouse model. Results showed that administration of AS-IV reduced albuminuria, ameliorated changes in the glomerular and tubular pathology, and decreased urinary NAG, NGAL, and TGF-β1 in db/db mice. AS-IV also attenuated the diabetes-related activation of Akt/mTOR, NFκB, and Erk1/2 signaling pathways without causing any detectable hepatotoxicity. Collectively, these findings showed AS-IV to be beneficial to type 2 diabetic nephropathy, which might be associated with the inhibition of Akt/mTOR, NFκB and Erk1/2 signaling pathways. PMID:27585918

  18. Sulfasalazine reduces inflammatory renal injury in unilateral ureteral obstruction.

    PubMed

    Demirbilek, Savas; Emre, Memet Hanefi; Aydin, Engin Nasuhi; Edali, Mehmet Naci; Aksoy, Rauf Tuğrul; Akin, Melih; Gürünlüoğlu, Kubilay; Tas, Erkan; Ay, Selma; Yilmaz, Zümrüt

    2007-06-01

    The purpose of this study was to test whether sulfasalazine has a protective action against interstitial inflammation and the development of renal fibrosis in obstructive nephropathy. Female rats were subjected to a sham (n = 10) or unilateral ureteral obstruction (UUO, n = 30). UUO was induced in rats by ligating the left ureter. Three days after operation, rats subjected to UUO were randomized to receive tretment with either sulfasalazine (100 mg/kg) or vehicle every day for the last 7 days of the experiment. At 10 days following UUO, the obstructed kidney exhibited tubulointerstitial injury and leukocyte infiltration (mainly monocytes) that were associated with high levels of reactive oxygen species, cytokines, transforming growth factor (TGF)-beta1, myeloperoxidase (MPO), and lipid peroxidation. Ten days after UUO, the obstructed kidney was also associated with increased nuclear factor kappa beta (NF-kappabeta) expression in saline-treated rats. Compared with sham-operated rats, UUO rat kidneys showed lower concentrations of antioxidant enzymes in the obstructed kidney tissue. All of these changes were significantly attenuated by treatment with sulfasalazine in the obstructed kidney. Sulfasalazine protected against the renal interstitial inflammation and tissue damage elicited by ureteral occlusion. Inhibition of the NF-kappabeta-dependent pathway and inflammatory response and oxidative stress inhibition is likely to be involved in the beneficial effects of sulfasalazine. PMID:17294223

  19. Prediction of acute renal failure following soft-tissue injury using the venous bicarbonate concentration.

    PubMed

    Muckart, D J; Moodley, M; Naidu, A G; Reddy, A D; Meineke, K R

    1992-12-01

    Sixty-four patients with soft-tissue injuries were studied prospectively to determine whether an initial venous bicarbonate concentration (VBC) of less than 17 mmol/L would predict the development of myoglobin-induced acute renal failure. The VBC was > 17 mmol/L in 59 patients, seven of whom had myoglobinuria. All recovered without renal complications. The remaining five patients all had VBC < 17 mmol/L and four had myoglobinuria. Acute renal failure developed in four patients (p < 0.001). The VBC on hospital arrival was the most accurate predictor of these patients' risk for the development of acute renal failure following soft-tissue injury. PMID:1474620

  20. Risk of Nonarteritic Anterior Ischemic Optic Neuropathy Following End-Stage Renal Disease.

    PubMed

    Chang, Yuh-Shin; Weng, Shih-Feng; Chang, Chun; Wang, Jhi-Joung; Su, Shih-Bin; Huang, Chien-Cheng; Wang, Jiu-Yao; Jan, Ren-Long

    2016-03-01

    To investigate the risk of nonarteritic anterior ischemic optic neuropathy (NAION) following end-stage renal disease (ESRD).A retrospective, nationwide, matched cohort study.ESRD patients identified by the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code 585.The study cohort included 93,804 ESRD patients registered with the Taiwan National Health Insurance Research Database between January 2000 and December 2009. An age- and sex-matched control group comprised 93,804 patients (case:control = 1:1) selected from the Taiwan Longitudinal Health Insurance Database 2000. Information for each patient was collected from the index date until December 2011. The incidence and risk of NAION were compared between the ESRD and control groups. The adjusted hazard ratio (HR) for NAION after adjustment for potential confounders was obtained by a Cox proportional hazard regression analysis. A Kaplan-Meier analysis was used to calculate the cumulative incidence rate of NAION.The incidence of NAION following ESRD.In total, 133 ESRD patients (0.14%) and 51 controls (0.05%) had NAION (P < 0.001) during the follow-up period, leading to a significantly elevated risk of NAION in the ESRD patients compared with the controls (incidence rate ratio = 3.14, 95% confidence interval [CI] = 2.11-4.67). After adjustment for potential confounders including diabetes mellitus, hypertension, hypotension, hyperlipidemia, and 2-way interaction terms between any 2 factors, ESRD patients were 3.12 times more likely to develop NAION than non-ESRD patients in the full cohort (adjusted HR = 3.12, 95% CI = 2.10-4.64). Additionally, patients with hypertension and hyperlipidemia showed higher incidence rates of NAION in the ESRD group compared with the controls: 2.31 (95% CI = 1.40-3.82) for hypertension and 2.72 (95% CI = 1.14-6.50) for hyperlipidemia.ESRD increased the risk of NAION, which is an interdisciplinary emergency. Close

  1. Brief exposure to hyperoxia depletes the glial progenitor pool and impairs functional recovery after hypoxic-ischemic brain injury

    PubMed Central

    Koch, Joshua D; Miles, Darryl K; Gilley, Jennifer A; Yang, Cui-Ping; Kernie, Steven G

    2009-01-01

    Patterns of hypoxic-ischemic brain injury in infants and children suggest vulnerability in regions of white matter development, and injured patients develop defects in myelination resulting in cerebral palsy and motor deficits. Reperfusion exacerbates the oxidative stress that occurs after such injuries and may impair recovery. Resuscitation after hypoxic-ischemic injury is routinely performed using 100% oxygen, and this practice may increase the oxidative stress that occurs during reperfusion and further damage an already compromised brain. We show that brief exposure (30 mins) to 100% oxygen during reperfusion worsens the histologic injury in young mice after unilateral brain hypoxia–ischemia, causes an accumulation of the oxidative metabolite nitrotyrosine, and depletes preoligodendrocyte glial progenitors present in the cortex. This damage can be reversed with administration of the antioxidant ebselen, a glutathione peroxidase mimetic. Moreover, mice recovered in 100% oxygen have a more disrupted pattern of myelination and develop a static motor deficit that mimics cerebral palsy and manifests itself by significantly worse performance on wire hang and rotorod motor testing. We conclude that exposure to 100% oxygen during reperfusion after hypoxic-ischemic brain injury increases secondary neural injury, depletes developing glial progenitors, interferes with myelination, and ultimately impairs functional recovery. PMID:18334993

  2. Induction of renal growth and injury in the intact rat kidney by dietary deficiency of antioxidants.

    PubMed Central

    Nath, K A; Salahudeen, A K

    1990-01-01

    We report induction of renal growth and injury in the intact rat kidney using a diet deficient in vitamin E and selenium. This diet was imposed in 3-wk-old male weanling rats, and after 9 wk, enhancement of growth, characterized by increased wet weight, dry weight, protein content, and DNA content appeared. Morphometric analyses revealed increased kidney volume, tubular epithelial volume, and mean glomerular volume. There were no differences in nephron number. The animals on the deficient diet displayed increased urinary protein excretion at 9 wk. Renal injury was also characterized by an interstitial cellular infiltrate and diminutions in glomerular filtration rate. Enhanced growth and injury were antedated by increased renal ammoniagenesis. The deficient diet did not induce metabolic acidosis, potassium depletion, glucose intolerance, or elevated plasma amino acid concentration. Enhancement of renal growth and ammoniagenesis by the deficient diet was not suppressible by chronic alkali therapy. Stimulation of renal growth could not be ascribed to increased intrarenal iron, induction of ornithine decarboxylase, or alterations in glomerular hemodynamics. Stimulation of renal ammoniagenesis by dietary deficiency of antioxidants is a novel finding, as is induction of growth and injury. We suggest that increased renal ammoniagenesis contributes to induction of renal growth and injury. Images PMID:2212007

  3. Cell Adhesion Molecules in Chemically-Induced Renal Injury

    PubMed Central

    Prozialeck, Walter C.; Edwards, Joshua R.

    2007-01-01

    Cell adhesion molecules are integral cell-membrane proteins that maintain cell-cell and cell-substrate adhesion, and in some cases, act as regulators of intracellular signaling cascades. In the kidney, cell adhesion molecules such as the cadherins, the catenins, ZO-1, occludin and the claudins are essential for maintaining the epithelial polarity and barrier integrity that are necessary for the normal absorption/excretion of fluid and solutes. A growing volume of evidence indicates that these cell adhesion molecules are important early targets for a variety of nephrotoxic substances including metals, drugs, and venom components. In addition, it is now widely appreciated that molecules such as ICAM-1, the integrins and selectins play important roles in the recruitment of leukocytes and inflammatory responses that are associated with nephrotoxic injury. This review summarizes the results of recent in vitro and in vivo studies indicating that these cell adhesion molecules may be primary molecular targets in many types of chemically-induced renal injury. Some of the specific agents that are discussed include Cd, Hg, Bi, cisplatin, aminoglycoside antibiotics, S-(1,2-dichlorovinyl-L-cysteine) (DCVC) and various venom toxins. This review also includes a discussion of the various mechanisms by which these substances can affect cell adhesion molecules in the kidney. PMID:17316817

  4. Roles of NAD+, PARP-1, and Sirtuins in Cell Death, Ischemic Brain Injury, and Synchrotron Radiation X-Ray-Induced Tissue Injury

    PubMed Central

    2013-01-01

    NAD+ plays crucial roles in a variety of biological processes including energy metabolism, aging, and calcium homeostasis. Multiple studies have also shown that NAD+ administration can profoundly decrease oxidative cell death and ischemic brain injury. A number of recent studies have further indicated that NAD+ administration can decrease ischemic brain damage, traumatic brain damage and synchrotron radiation X-ray-induced tissue injury by such mechanisms as inhibiting inflammation, decreasing autophagy, and reducing DNA damage. Our latest study that applies nano-particles as a NAD+ carrier has also provided first direct evidence demonstrating a key role of NAD+ depletion in oxidative stress-induced ATP depletion. Poly(ADP-ribose) polymerase-1 (PARP-1) and sirtuins are key NAD+-consuming enzymes that mediate multiple biological processes. Recent studies have provided new information regarding PARP-1 and sirtuins in cell death, ischemic brain damage and synchrotron radiation X-ray-induced tissue damage. These findings have collectively supported the hypothesis that NAD+ metabolism, PARP-1 and sirtuins play fundamental roles in oxidative stress-induced cell death, ischemic brain injury, and radiation injury. The findings have also supported “the Central Regulatory Network Hypothesis”, which proposes that a fundamental network that consists of ATP, NAD+ and Ca2+ as its key components is the essential network regulating various biological processes. PMID:24386592

  5. Mice lacking glutamate carboxypeptidase II are protected from peripheral neuropathy and ischemic brain injury.

    PubMed

    Bacich, Dean J; Wozniak, Krystyna M; Lu, X-C May; O'Keefe, Denize S; Callizot, Noelle; Heston, Warren D W; Slusher, Barbara S

    2005-10-01

    Excessive glutamate release is associated with neuronal damage. A new strategy for the treatment of neuronal injury involves inhibition of the neuropeptidase glutamate carboxypeptidase II (GCP II), also known as N-acetylated alpha-linked acidic dipeptidase. GCP II is believed to mediate the hydrolysis of N-acetyl-aspartyl-glutamate (NAAG) to glutamate and N-acetyl-aspartate, and inhibition of NAAG peptidase activity (by GCP II and other peptidases) is neuroprotective. Mice were generated in which the Folh1 gene encoding GCP II was disrupted (Folh1-/- mice). No overt behavioral differences were apparent between Folh1-/- mice and wild-type littermates, with respect to their overall performance in locomotion, coordination, pain threshold, cognition and psychiatric behavioral paradigms. Morphological analysis of peripheral nerves, however, showed significantly smaller axons (reduced myelin sheaths and axon diameters) in sciatic nerves from Folh1-/- mice. Following sciatic nerve crush, Folh1-/- mice suffered less injury and recovered faster than wild-type littermates. In a model of ischemic injury, the Folh1-/- mice exhibited a significant reduction (p < 0.05) in infarct volume compared with their wild-type littermates when subjected to middle cerebral artery occlusion, a model of stroke. These findings support the hypothesis that GCP II inhibitors may represent a novel treatment for peripheral neuropathies as well as stroke. PMID:16190866

  6. Transplantation of placenta-derived mesenchymal stem cells enhances angiogenesis after ischemic limb injury in mice.

    PubMed

    Xie, Nanzi; Li, Zhihong; Adesanya, Timothy M; Guo, Weixin; Liu, Yang; Fu, Minghuan; Kilic, Ahmet; Tan, Tao; Zhu, Hua; Xie, Xiaoyun

    2016-01-01

    Mesenchymal stem cell-based therapy has emerged as a promising approach for the treatment of peripheral arterial disease. The purpose of this study was to examine the potential effects of human placenta-derived mesenchymal stem cells (PMSCs) on mouse hindlimb ischemia. PMSCs were isolated from human placenta tissue and characterized by flow cytometry. An in vivo surgical ligation-induced murine limb ischemia model was generated with fluorescent dye (CM-DiI) labelled PMSCs delivered via intramuscular injection. Our data show that PMSCs treatment significantly enhanced microvessel density, improved blood perfusion and diminished pathologies in ischemic mouse hindlimbs as compared to those in the control group. Further immunostaining studies suggested that injected PMSCs can incorporate into the vasculature and differentiate into endothelial and smooth muscle cells to enhance angiogenesis in ischemic hind limbs. This may in part explain the beneficial effects of PMSCs treatment. Taken together, we found that PMSCs treatment might be an effective treatment modality for treatment of ischemia-induced injury to mouse hind limbs by enhancement of angiogenesis. PMID:26282458

  7. Cystathionine β-Synthase Inhibition Is a Potential Therapeutic Approach to Treatment of Ischemic Injury

    PubMed Central

    Chan, Su Jing; Chai, Chou; Lim, Tze Wei; Yamamoto, Mie; Lo, Eng H; Lai, Mitchell Kim Peng

    2015-01-01

    Hydrogen sulfide (H2S) has been reported to exacerbate stroke outcome in experimental models. Cystathionine β-synthase (CBS) has been implicated as the predominant H2S-producing enzyme in central nervous system. When SH-SY5Y cells were transfected to overexpress CBS, these cells were able to synthesize H2S when exposed to high levels of enzyme substrates but not substrate concentrations that may reflect normal physiological conditions. At the same time, these cells demonstrated exacerbated cell death when subjected to oxygen and glucose deprivation (OGD) together with high substrate concentrations, indicating that H2S production has a detrimental effect on cell survival. This effect could be abolished by CBS inhibition. The same effect was observed with primary astrocytes exposed to OGD and high substrates or sodium hydrosulfide. In addition, CBS was upregulated and activated by truncation in primary astrocytes subjected to OGD. When rats were subjected to permanent middle cerebral artery occlusion, CBS activation was also observed. These results imply that in acute ischemic conditions, CBS is upregulated and activated by truncation causing an increased production of H2S, which exacerbate the ischemic injuries. Therefore, CBS inhibition may be a viable approach to stroke treatment. PMID:25873304

  8. Changes in Cerebral Oxidative Metabolism during Neonatal Seizures Following Hypoxic–Ischemic Brain Injury

    PubMed Central

    Mitra, Subhabrata; Bale, Gemma; Mathieson, Sean; Uria-Avellanal, Cristina; Meek, Judith; Tachtsidis, Ilias; Robertson, Nicola J.

    2016-01-01

    Seizures are common following hypoxic–ischemic brain injury in newborn infants. Prolonged or recurrent seizures have been shown to exacerbate neuronal damage in the developing brain; however, the precise mechanism is not fully understood. Cytochrome-c-oxidase is responsible for more than 90% of ATP production inside mitochondria. Using a novel broadband near-infrared spectroscopy system, we measured the concentration changes in the oxidation state of cerebral cytochrome-c-oxidase (Δ[oxCCO]) and hemodynamics during recurrent neonatal seizures following hypoxic–ischemic encephalopathy in a newborn infant. A rapid increase in Δ[oxCCO] was noted at the onset of seizures along with a rise in the baseline of amplitude-integrated electroencephalogram. Cerebral oxygenation and cerebral blood volume fell just prior to the seizure onset but recovered rapidly during seizures. Δ[oxCCO] during seizures correlated with changes in mean electroencephalogram voltage indicating an increase in neuronal activation and energy demand. The progressive decline in the Δ[oxCCO] baseline during seizures suggests a progressive decrease of mitochondrial oxidative metabolism. PMID:27559538

  9. Changes in Cerebral Oxidative Metabolism during Neonatal Seizures Following Hypoxic-Ischemic Brain Injury.

    PubMed

    Mitra, Subhabrata; Bale, Gemma; Mathieson, Sean; Uria-Avellanal, Cristina; Meek, Judith; Tachtsidis, Ilias; Robertson, Nicola J

    2016-01-01

    Seizures are common following hypoxic-ischemic brain injury in newborn infants. Prolonged or recurrent seizures have been shown to exacerbate neuronal damage in the developing brain; however, the precise mechanism is not fully understood. Cytochrome-c-oxidase is responsible for more than 90% of ATP production inside mitochondria. Using a novel broadband near-infrared spectroscopy system, we measured the concentration changes in the oxidation state of cerebral cytochrome-c-oxidase (Δ[oxCCO]) and hemodynamics during recurrent neonatal seizures following hypoxic-ischemic encephalopathy in a newborn infant. A rapid increase in Δ[oxCCO] was noted at the onset of seizures along with a rise in the baseline of amplitude-integrated electroencephalogram. Cerebral oxygenation and cerebral blood volume fell just prior to the seizure onset but recovered rapidly during seizures. Δ[oxCCO] during seizures correlated with changes in mean electroencephalogram voltage indicating an increase in neuronal activation and energy demand. The progressive decline in the Δ[oxCCO] baseline during seizures suggests a progressive decrease of mitochondrial oxidative metabolism. PMID:27559538

  10. Neonatal Hypoxic/Ischemic Brain Injury Induces Production of Calretinin-Expressing Interneurons in the Striatum

    PubMed Central

    YANG, ZHENGANG; YOU, YAN; LEVISON, STEVEN W.

    2011-01-01

    Ischemia-induced striatal neurogenesis from progenitors in the adjacent subventricular zone (SVZ) in young and adult rodents has been reported. However, it has not been established whether the precursors that reside in the SVZ retain the capacity to produce the full range of striatal neurons that has been destroyed. By using a neonatal rat model of hypoxic/ischemic brain damage, we show here that virtually all of the newly produced striatal neurons are calretinin (CR)-immunoreactive (+), but not DARPP-32+, calbindin-D-28K+, parvalbumin+, somatostatin+, or choline acetyltransferase+. Retroviral fate-mapping studies confirm that these newly born CR++neurons are indeed descendants of the SVZ. Our studies indicate that, although the postnatal SVZ has the capacity to produce a range of neurons, only a subset of this repertoire is manifested in the brain after injury. PMID:18720478

  11. BrdU-positive cells in the neonatal mouse hippocampus following hypoxic-ischemic brain injury

    PubMed Central

    Bartley, John; Soltau, Thomas; Wimborne, Hereward; Kim, Sunjun; Martin-Studdard, Angeline; Hess, David; Hill, William; Waller, Jennifer; Carroll, James

    2005-01-01

    Background Mechanisms that affect recovery from fetal and neonatal hypoxic-ischemic (H-I) brain injury have not been fully elucidated. The incidence of intrapartum asphyxia is approximately 2.5%, but the occurrence of adverse clinical outcome is much lower. One of the factors which may account for this relatively good outcome is the process of neurogenesis, which has been described in adult animals. We used a neonatal mouse model to assess new cells in the hippocampus after H-I injury. Results Neonatal mice underwent permanent unilateral carotid ligation on the seventh postnatal day followed by exposure to 8% hypoxia for 75 minutes. The presence of new cells was determined by bromodeoxyuridine (BrdU) incorporation into cells with sacrifice of the animals at intervals. Brain sections were stained for BrdU in combination with neuronal, glial, endothelial and microglial stains. We found a significant increase in BrdU-positive cells in the neonatal mouse hippocampus in the injured area compared to the non-injured area, most prominent in the dentate gyrus (DG) (154.5 ± 59.6 v. 92.9 ± 32.7 at 3 days after injury; 68.9 ± 23.4 v. 52.4 ± 17.1 at 35 days after injury, p < 0.0011). Among the cells which showed differentiation, those which were stained as either microglial or endothelial cells showed a peak increase at three days after the injury in the DG, injured versus non-injured side (30.5 ± 17.8 v. 2.7 ± 2.6, p < 0.0002). As in the adult animal, neurogenesis was significantly increased in the DG with injury (15.0 ± 4.6 v. 5.2 ± 1.6 at 35 days after injury, p < 0.0002), and this increase was subsequent to the appearance of the other dividing cells. Numbers of new oligodendrocytes were significantly higher in the DG on the non-injured side (7.0 ± 24.2 v. 0.1 ± 0.3, p < 0.0002), suggesting that oligodendrocyte synthesis was reduced in the injured hippocampus. Conclusion These findings demonstrate that the neonatal animal responds to brain injury with neurogenesis

  12. Protective effects of drag-reducing polymers on ischemic reperfusion injury of isolated rat heart.

    PubMed

    Hu, Feng; Wang, Yali; Gong, Kaizheng; Ge, Gaoyuan; Cao, Mingqiang; Zhao, Pei; Sun, Xiaoning; Zhang, Zhengang

    2016-01-01

    Drag-reducing polymers (DRPs) are blood-soluble macromolecules that can increase blood flow and reduce vascular resistance. The purpose of the present study was to observe the effect of DRPs on ischemic reperfusion (I/R) injury of isolated rat hearts. Experiments were performed on isolated rat hearts subjected to 30 min of ischemia followed by 90 min of reperfusion in Langendorff preparations. Adult Wistar rats were divided into the following five groups: control group, I/R group, group III (I/R and 2×10(-7)  g/ml PEO reperfusion), group IV (I/R and 1×10(-6)  g/ml PEO reperfusion), and group V (I/R and 5×10(-6)  g/ml PEO reperfusion). Left ventricular end-diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP), maximum rate of ventricular pressure increase and decrease ( ± dp/dtmax), heart rate (HR) and coronary flow were measured. Lactate dehydrogenase (LDH) and creatine kinase (CK) activity and coronary flow, myocardial infarction size and cardiomyocytes apoptosis were also assayed. Our results showed that PEO decreased LVEDP and increased LVSP, ± dP/dtmax in group IV and group V compared with the I/R group (all P <  0.05). The coronary flow significantly increased and the activities of LDH and CK in the coronary flow significantly decreased in group IV and group V compared with those in the I/R group (all P <  0.05). Cell apoptosis and myocardial infarction size were reduced in group IV and group V compared with the I/R group (all P <  0.05). Collectively, these results suggested that DRPs had a protective effect on cardiac I/R injury of isolated rat hearts and it may offer a new potential approach for the treatment of acute ischemic heart diseases. PMID:25633566

  13. Protein disulfide isomerase as a novel target for cyclopentenone prostaglandins: implications for hypoxic ischemic injury

    PubMed Central

    Liu, Hao; Chen, Jie; Li, Wenjin; Rose, Marie E.; Shinde, Sunita N.; Balasubramani, Manimalha; Uechi, Guy T.; Mutus, Bülent; Graham, Steven H.; Hickey, Robert W.

    2016-01-01

    Cyclooxygenase-2 (COX-2) is an important contributor to ischemic brain injury. Identification of the downstream mediators of COX-2 toxicity may allow the development of targeted therapies. Of particular interest is the cyclopentenone family of prostaglandin metabolites. Cyclopentenone prostaglandins (CyPGs) are highly reactive molecules that form covalent bonds with cellular thiols. Protein disulfide isomerase (PDI) is an important molecule for the restoration of denatured proteins following ischemia. Because PDI has several thiols, including thiols within the active thioredoxin-like domain, we hypothesized that PDI is a target of CyPGs and that CyPG binding of PDI is detrimental. CyPG–PDI binding was detected in vitro via immunoprecipitation and MS. CyPG–PDI binding decreased PDI enzymatic activity in recombinant PDI treated with CyPG, and PDI immunoprecipitated from neuronal culture treated with CyPG or anoxia. Toxic effects of binding were demonstrated in experiments showing that: (a) pharmacologic inhibition of PDI increased cell death in anoxic neurons, (b) PDI overexpression protected neurons exposed to anoxia and SH-SY5Y cells exposed to CyPG, and (c) PDI overexpression in SH-SY5Y cells attenuated ubiquitination of proteins and decreased activation of pro-apoptotic caspases. In conclusion, CyPG production and subsequent binding of PDI is a novel and potentially important mechanism of ischemic brain injury. We show that CyPGs bind to PDI, cyclopentenones inhibit PDI activity, and CyPG–PDI binding is associated with increased neuronal susceptibility to anoxia. Additional studies are necessary to determine the relative role of CyPG-dependent inhibition of PDI activity in ischemia and other neurodegenerative disorders. PMID:25754985

  14. Influence of exercise training on ischemic brain injury in type 1 diabetic rats.

    PubMed

    Arrick, Denise M; Sun, Hong; Mayhan, William G

    2012-10-01

    While exercise training (ExT) appears to influence cerebrovascular function during type 1 diabetes (T1D), it is not clear whether this beneficial effect extends to protecting the brain from ischemia-induced brain injury. Thus our goal was to examine whether modest ExT could influence transient focal ischemia-induced brain injury along with nitric oxide synthase (NOS)-dependent dilation of cerebral (pial) arterioles during T1D. Sprague-Dawley rats were divided into four groups: nondiabetic sedentary, nondiabetic ExT, diabetic (streptozotocin; 50 mg/kg ip) sedentary, and diabetic ExT. In the first series of studies, we measured infarct volume in all groups of rats following right MCA occlusion for 2 h, followed by 24 h of reperfusion. In a second series of studies, a craniotomy was performed over the parietal cortex, and we measured responses of pial arterioles to an endothelial NOS (eNOS)-dependent, a neuronal NOS (nNOS)-dependent, and a NOS-independent agonist in all groups of rats. We found that sedentary diabetic rats had significantly larger total, cortical, and subcortical infarct volumes following ischemia-reperfusion than sedentary nondiabetic, nondiabetic ExT, and diabetic ExT rats. Infarct volumes were similar in sedentary nondiabetic, ExT nondiabetic, and ExT diabetic rats. In contrast, ExT did not alter infarct size in nondiabetic compared with sedentary nondiabetic rats. In addition, ExT diabetic rats had impaired eNOS- and nNOS-dependent, but not NOS-independent, vasodilation that was restored by ExT. Thus ExT of T1D rats lessened ischemic brain injury following middle cerebral artery occlusion and restored impaired eNOS- and nNOS-dependent vascular function. Since the incidence of ischemic stroke is increased during T1D, we suggest that our finding are significant in that modest ExT may be a viable preventative therapeutic approach to lessen ischemia-induced brain injury that may occur in T1D subjects. PMID:22858624

  15. Magnesium sulfate protects oligodendrocyte lineage cells in a rat cell-culture model of hypoxic-ischemic injury.

    PubMed

    Itoh, Kanako; Maki, Takakuni; Shindo, Akihiro; Egawa, Naohiro; Liang, Anna C; Itoh, Naoki; Lo, Eng H; Lok, Josephine; Arai, Ken

    2016-05-01

    Hypoxic-ischemic (HI) brain injury in newborns results in serious damage. Magnesium sulfate has been clinically used as a cyto-protective agent against HI brain injury in newborns in some countries, including Japan. However, it is not clear how magnesium exerts this effect and how it acts on the individual types of cells within the newborn brain. In this study, we exposed cultured rat oligodendrocyte precursor cells to magnesium sulfate during the period when they differentiate into oligodendrocytes, and showed that magnesium-exposed oligodendrocytes exhibited more resistance to HI injury. Our data may support the use of magnesium sulfate in the clinical setting. PMID:26699082

  16. Ischemia preconditioning protects astrocytes from ischemic injury through 14-3-3γ.

    PubMed

    Pang, Ying; Chai, Chao Rui; Gao, Kai; Jia, Xi Hua; Kong, Jin Ge; Chen, Xiao Qian; Vatcher, Greg; Chen, Jian Guo; Yu, Albert Cheung Hoi

    2015-10-01

    Stroke is a leading cause of death and disability, and new strategies are required to reduce neuronal injury and improve prognosis. Ischemia preconditioning (IPC) is an intrinsic phenomenon that protects cells from subsequent ischemic injury and might provide promising mechanisms for clinical treatment. In this study, primary astrocytes exhibited significantly less cell death than control when exposed to different durations of IPC (15, 30, 60, or 120 min). A 15-min duration was the most effective IPC to protect astrocytes from 8-hr-ischemia injury. The protective mechanisms of IPC involve the upregulation of protective proteins, including 14-3-3γ, and attenuation of malondialdehyde (MDA) content and ATP depletion. 14-3-3γ is an antiapoptotic intracellular protein that was significantly upregulated for up to 84 hr after IPC. In addition, IPC promoted activation of the c-Jun N-terminal kinase (JNK), extracellular signal-related kinase (ERK)-1/2, p38, and protein kinase B (Akt) signaling pathways. When JNK was specifically inhibited with SP600125, the upregulation of 14-3-3γ induced by IPC was almost completely abolished; however, there was no effect on ATP or MDA levels. This suggests that, even though both energy preservation and 14-3-3γ up-regulation were turned on by IPC, they were controlled by different pathways. The ERK1/2, p38, and Akt signaling pathways were not involved in the 14-3-3γ upregulation and energy preservation. These results indicate that IPC could protect astrocytes from ischemia injury by inducing 14-3-3γ and by alleviating energy depletion through different pathways, suggesting multiple protection of IPC and providing new insights into potential stroke therapies. PMID:25711139

  17. Prognostics factors for mortality and renal recovery in critically ill patients with acute kidney injury and renal replacement therapy

    PubMed Central

    Gaião, Sérgio Mina; Gomes, André Amaral; Paiva, José Artur Osório de Carvalho

    2016-01-01

    Objective Identify prognostic factors related to mortality and non-recovery of renal function. Methods A prospective single-center study was conducted at the intensive care medicine department of a university hospital between 2012 and 2015. Patients with acute kidney injury receiving continuous renal replacement therapy were included in the study. Clinical and analytical parameters were collected, and the reasons for initiation and discontinuation of renal replacement therapy were examined. Results A total of 41 patients were included in the study, of whom 43.9% had sepsis. The median Simplified Acute Physiology Score II (SAPSII) was 56 and the mortality was 53.7%, with a predicted mortality of 59.8%. The etiology of acute kidney injury was often multifactorial (56.1%). Survivors had lower cumulative fluid balance (median = 3,600mL, interquartile range [IQR] = 1,175 - 8,025) than non-survivors (median = 12,000mL, IQR = 6,625 - 17,875; p = 0.004). Patients who recovered renal function (median = 51.0, IQR = 45.8 - 56.2) had lower SAPS II than those who do not recover renal function (median = 73, IQR = 54 - 85; p = 0.005) as well as lower fluid balance (median = 3,850, IQR = 1,425 - 8,025 versus median = 11,500, IQR = 6,625 - 16,275; p = 0.004). Conclusions SAPS II at admission and cumulative fluid balance during renal support therapy were risk factors for mortality and non-recovery of renal function among critically ill patients with acute kidney injury needing renal replacement therapy. PMID:27096679

  18. Low renal oximetry correlates with acute kidney injury after infant cardiac surgery.

    PubMed

    Owens, Gabe E; King, Karen; Gurney, James G; Charpie, John R

    2011-02-01

    Acute kidney injury (AKI) is a frequent complication after cardiopulmonary bypass surgery during infancy. Standard methods for evaluating renal function are not particularly sensitive nor are proximate indicators of renal dysfunction that allow intervention in real time. Near-infrared spectroscopy (NIRS) is a newer noninvasive technology that continuously evaluates regional oximetry and may correlate with renal injury and adverse outcomes after cardiac surgery in infants. This prospective observational study enrolled 40 infants (age, <12 months) undergoing biventricular repair. Continuous renal oximetry data were collected for the first 48 postoperative hours and correlated with postoperative course, standard laboratory data, and the occurrence of acute renal injury. Subjects with low renal oximetry (below 50% for >2 h) had significantly higher postoperative peak creatinine levels by 48 h (0.8 ± 0.4 vs. 0.52 ± 0.2; p = 0.003) and a higher incidence of AKI (50 vs. 3.1%; p = 0.003) than those with normal renal oximetry. These subjects also required more ventilator days and greater vasoactive support, and they had elevated lactate levels. Prolonged low renal near-infrared oximetry appears to correlate with renal dysfunction, decreased systemic oxygen delivery, and the overall postoperative course in infants with congenital heart disease undergoing biventricular repair. PMID:21085945

  19. TEMPONE reduces renal dysfunction and injury mediated by oxidative stress of the rat kidney.

    PubMed

    Patel, Nimesh S A; Chatterjee, Prabal K; Chatterjee, Bristi E; Cuzzocrea, Salvatore; Serraino, Ivana; Brown, Paul A J; Stewart, Keith N; Mota-Filipe, Helder; Thiemermann, Christoph

    2002-12-01

    Here we investigate the effects of the stable, water-soluble nitroxyl radical, TEMPONE, on renal dysfunction and injury caused by ischemia/reperfusion (I/R) of the rat kidney in vivo. TEMPONE significantly improved both glomerular and tubular function (serum urea, creatinine, creatinine clearance, and fractional excretion of Na(+)) in a dose-dependent manner and significantly attenuated the reperfusion-injury associated with I/R (urinary N-acetyl-beta-D-glucosaminidase, aspartate aminotransferase, assessment of renal histology). TEMPONE also markedly reduced the immunohistochemical evidence of the formation of nitrotyrosine and poly(ADP-ribose), indicating reduction of nitrosative and oxidative stress, respectively. The latter was reflected in vitro, where TEMPONE significantly reduced cellular injury of primary cultures of rat renal proximal tubular (PT) cells caused by hydrogen peroxide in a dose-dependent manner. Importantly, in contrast to its in vivo metabolite TEMPOL (which also provided protective effects against renal I/R and oxidative stress of PT cells), TEMPONE reduced renal dysfunction and injury without causing a significant reduction in blood pressure upon administration. These results suggest, for the first time, that TEMPONE can reduce the renal dysfunction and injury caused by I/R and the injury caused to PT cells by oxidative stress without producing the adverse cardiovascular effects observed when using other nitroxyl radicals. PMID:12446215

  20. Optical Spectroscopy Approach for the Predictive Assessment of Kidney Functional Recovery Following Ischemic Injury

    SciTech Connect

    Raman, R N; Pivetti, C D; Rubenchik, A M; Matthews, D L; Troppmann, C; Demos, S G

    2010-02-11

    Tissue that has undergone significant yet unknown amount of ischemic injury is frequently encountered in organ transplantation and trauma clinics. With no reliable real-time method of assessing the degree of injury incurred in tissue, surgeons generally rely on visual observation which is subjective. In this work, we investigate the use of optical spectroscopy methods as a potentially more reliable approach. Previous work by various groups was strongly suggestive that tissue autofluorescence from NADH obtained under UV excitation is sensitive to metabolic response changes. To test and expand upon this concept, we monitored autofluorescence and light scattering intensities of injured vs. uninjured rat kidneys via multimodal imaging under 355 nm, 325 nm, and 266 nm excitation as well as scattering under 500 nm illumination. 355 nm excitation was used to probe mainly NADH, a metabolite, while 266 nm excitation was used to probe mainly tryptophan to correct for non-metabolic signal artifacts. The ratio of autofluorescence intensities derived under these two excitation wavelengths was calculated and its temporal profile was fit to a relaxation model. Time constants were extracted, and longer time constants were associated with kidney dysfunction. Analysis of both the autofluorescence and light scattering images suggests that changes in microstructure tissue morphology, blood absorption spectral characteristics, and pH contribute to the behavior of the observed signal which may be used to obtain tissue functional information and offer predictive capability.

  1. Multiparametric, Longitudinal Optical Coherence Tomography Imaging Reveals Acute Injury and Chronic Recovery in Experimental Ischemic Stroke

    PubMed Central

    Srinivasan, Vivek J.; Mandeville, Emiri T.; Can, Anil; Blasi, Francesco; Climov, Mihail; Daneshmand, Ali; Lee, Jeong Hyun; Yu, Esther; Radhakrishnan, Harsha; Lo, Eng H.; Sakadžić, Sava; Eikermann-Haerter, Katharina; Ayata, Cenk

    2013-01-01

    Progress in experimental stroke and translational medicine could be accelerated by high-resolution in vivo imaging of disease progression in the mouse cortex. Here, we introduce optical microscopic methods that monitor brain injury progression using intrinsic optical scattering properties of cortical tissue. A multi-parametric Optical Coherence Tomography (OCT) platform for longitudinal imaging of ischemic stroke in mice, through thinned-skull, reinforced cranial window surgical preparations, is described. In the acute stages, the spatiotemporal interplay between hemodynamics and cell viability, a key determinant of pathogenesis, was imaged. In acute stroke, microscopic biomarkers for eventual infarction, including capillary non-perfusion, cerebral blood flow deficiency, altered cellular scattering, and impaired autoregulation of cerebral blood flow, were quantified and correlated with histology. Additionally, longitudinal microscopy revealed remodeling and flow recovery after one week of chronic stroke. Intrinsic scattering properties serve as reporters of acute cellular and vascular injury and recovery in experimental stroke. Multi-parametric OCT represents a robust in vivo imaging platform to comprehensively investigate these properties. PMID:23940761

  2. Optical spectroscopy approach for the predictive assessment of kidney functional recovery following ischemic injury

    NASA Astrophysics Data System (ADS)

    Raman, Rajesh N.; Pivetti, Christopher D.; Rubenchik, Alexander M.; Matthews, Dennis L.; Troppmann, Christoph; Demos, Stavros G.

    2010-02-01

    Tissue that has undergone significant yet unknown amount of ischemic injury is frequently encountered in organ transplantation and trauma clinics. With no reliable real-time method of assessing the degree of injury incurred in tissue, surgeons generally rely on visual observation which is subjective. In this work, we investigate the use of optical spectroscopy methods as a potentially more reliable approach. Previous work by various groups was strongly suggestive that tissue autofluorescence from NADH obtained under UV excitation is sensitive to metabolic response changes. To test and expand upon this concept, we monitored autofluorescence and light scattering intensities of injured vs. uninjured rat kidneys via multimodal imaging under 355 nm, 325 nm, and 266 nm excitation as well as scattering under 500 nm illumination. 355 nm excitation was used to probe mainly NADH, a metabolite, while 266 nm excitation was used to probe mainly tryptophan to correct for non-metabolic signal artifacts. The ratio of autofluorescence intensities derived under these two excitation wavelengths was calculated and its temporal profile was fit to a relaxation model. Time constants were extracted, and longer time constants were associated with kidney dysfunction. Analysis of both the autofluorescence and light scattering images suggests that changes in microstructure tissue morphology, blood absorption spectral characteristics, and pH contribute to the behavior of the observed signal which may be used to obtain tissue functional information and offer predictive capability.

  3. Sympathetic nervous response to ischemia-reperfusion injury in humans is altered with remote ischemic preconditioning.

    PubMed

    Lambert, Elisabeth A; Thomas, Colleen J; Hemmes, Robyn; Eikelis, Nina; Pathak, Atul; Schlaich, Markus P; Lambert, Gavin W

    2016-08-01

    Sympathetic neural activation may be detrimentally involved in tissue injury caused by ischemia-reperfusion (IR). We examined the effects of experimental IR in the forearm on sympathetic nerve response, finger reactive hyperemia, and oxidative stress, and the protection afforded by applying remote ischemic preconditioning (RIPC). Ischemia was induced in the forearm for 20 min in healthy volunteers. RIPC was induced by applying two cycles, 5 min each, of ischemia and reperfusion to the upper leg immediately before IR. We examined muscle sympathetic nerve activity (MSNA) in the contralateral leg using microneurography, finger reactive hyperemia [ischemic reactive hyperemia index (RHI)], erythrocyte production of reduced gluthathione (GSH), and plasma nitric oxide (NO) concentration. In controls (no RIPC; n = 15), IR increased MSNA in the early and late phase of ischemia (70% at 5 min; 101% at 15 min). In subjects who underwent RIPC (n = 15), the increase in MSNA was delayed to the late phase of ischemia and increased only by 40%. GSH increased during ischemia in the control group (P = 0.05), but not in those who underwent RIPC. Nitrate and nitrite concentration, taken as an index of NO availability, decreased during the reperfusion period in control individuals (P < 0.05), while no change was observed in those who underwent RIPC. Experimental IR did not affect RHI in the control condition, but a significant vasodilatory response occurred in the RIPC group (P < 0.05). RIPC attenuated ischemia-induced sympathetic activation, prevented the production of an erythrocyte marker of oxidative stress and the reduction of NO availability, and ameliorated RHI. PMID:27288436

  4. Insights into the role of iron in immature rat model of hypoxic-ischemic brain injury

    PubMed Central

    Wang, Zi-Wei; Yang, Li-Jun; Ding, Ying-Xue; Chang, Yan-Zhong; Cui, Hong

    2016-01-01

    This study aimed to investigate the role of iron in the occurrence and development of hypoxic-ischemic brain injury (HIBI) in immature rat models using 3-day-old Sprague Dawley rats. Normal control (NC), hypoxic-ischemic (HI), anemia, HI + ischemia, early iron treatment and late iron treatment groups were established. Rat brain tissue sections were stained with hematoxylin and eosin and pathologically evaluated. Iron content and mRNA expression levels of iron regulatory protein 2 (IRP2) and transferrin receptor in the brain tissues were measured. Ultrastructural changes in the actin, microtubules, myelin and mitochondria of oligodendrocytes and axons were examined by electron microscopy. Numbers of viable myelin sheaths and oligodendrocytes in the periventricular area were also observed. Pathological damage of brain tissue in the HI group was markedly increased compared with that in the NC group. Furthermore, there was a higher iron content and reduced number of viable oligodendrocytes in the periventricular area of the HI group compared with the NC group. No significant difference in iron content was observed between the HI + anemia and NC groups. The number of viable oligodendrocytes in the HI + anemia group was increased compared with that in the HI group, and the number in the HI + anemia group with late iron treatment was lower compared with that in the NC group and increased compared with that in the HI + anemia group. Electron microscopy revealed a significantly higher number of myelin sheaths in the HI + anemia group than in the HI group. IRP2 mRNA expression levels in the brain tissues were significantly decreased in the HI + anemia group compared with the HI group. The results suggest that anemia may reduce the rate of increase of iron content of the brain following HI. However, the early occurrence of anemia may protect against HIBI. PMID:27602087

  5. Effects of progesterone on hippocampal ultrastructure and expression of inflammatory mediators in neonatal rats with hypoxic-ischemic brain injury.

    PubMed

    Li, Xiaojuan; Zhang, Junhe; Zhu, Xiaoqian; Hou, Ruanling; Li, Xinjuan; Dong, Xianhong; Wang, Xiaoyin; Lu, Chengbiao

    2014-05-01

    Progesterone (PROG) has been shown to exhibit a protective function against hypoxic-ischemic brain damage. The aim of the present study was to study the effects of PROG in a neonatal rat model of hypoxic-ischemic brain injury. A total of 30 Wistar rats, aged 7 days, were randomly divided into three groups: Sham, model and PROG. The rats in the model and PROG groups underwent a left common carotid artery ligation and were placed in a sealed container at 37°C with 8% O2 and 92% N2 gas mixtures for 2.5 h to establish animal models of hypoxic-ischemic encephalopathy. The rats in the PROG group were intraperitoneally treated with 8 mg/kg PROG solution 30 min prior to the induction of hypoxia-ischemia. All animals were sacrificed after 24 h and neuronal changes were observed with electron microscopy to investigate the hypoxic-ischemic brain damage. The protein and mRNA expression levels of tumor necrosis factor-α (TNF-α) and nuclear factor-κB (NF-κB) in the hippocampus were detected by immunohistochemistry and quantitative polymerase chain reaction, respectively. The results revealed that the neuronal structures in the sham group were normal. The neuronal structures in the model group exhibited cavitation changes, but these were reduced following PROG administration. The protein and mRNA expression levels of TNF-α and NF-κB in the hippocampal neurons were increased in the model group, and pretreatment with 8 mg/kg PROG was shown to reduce the expression levels of these inflammatory mediators. Therefore, PROG was shown to exert an important protective function in hypoxic-ischemic brain injury by inhibiting the cascade of inflammatory injury induced by TNF-α and NF-κB. PMID:24940430

  6. Inhibition of glutamate carboxypeptidase II (NAALADase) protects against dynorphin A-induced ischemic spinal cord injury in rats.

    PubMed

    Long, Joseph B; Yourick, Debra L; Slusher, Barbara S; Robinson, Michael B; Meyerhoff, James L

    2005-01-31

    Glutamate carboxypeptidase (GCP) II (EC 3.4.17.21), which is also known as N-acetylated-alpha-linked acidic dipeptidase (NAALADase), hydrolyses the endogenous acidic dipeptide N-acetylaspartylglutamate (NAAG), yielding N-acetyl-aspartate and glutamate. Inhibition of this enzyme by 2-(phosphonomethyl) pentanedioic acid (2-PMPA) has been shown to protect against ischemic injury to the brain and hypoxic and metabolic injury to neuronal cells in culture, presumably by increasing and decreasing the extracellular concentrations of NAAG and glutamate, respectively. Since both NAAG and GCP II are found in especially high concentrations in the spinal cord, injuries to the spinal cord involving pathophysiological elevations in extracellular glutamate might be particularly responsive to GCP II inhibition. Lumbar subarachnoid injections of dynorphin A in rats cause ischemic spinal cord injury, elevated extracellular glutamate and a persistent hindlimb paralysis that is mediated through excitatory amino acid receptors. We therefore used this injury model to evaluate the protective effects of 2-PMPA. When coadministered with dynorphin A, 2-PMPA significantly attenuated the dynorphin A-induced elevations in cerebrospinal fluid glutamate levels and by 24 h postinjection caused significant dose-dependent improvements in motor scores that were associated with marked histopathological improvements. These results indicate that 2-PMPA provides effective protection against excitotoxic spinal cord injury. PMID:15680261

  7. Accelerated recovery of renal mitochondrial and tubule homeostasis with SIRT1/PGC-1α activation following ischemia–reperfusion injury

    SciTech Connect

    Funk, Jason A.; Schnellmann, Rick G.

    2013-12-01

    Kidney ischemia–reperfusion (I/R) injury elicits cellular injury in the proximal tubule, and mitochondrial dysfunction is a pathological consequence of I/R. Promoting mitochondrial biogenesis (MB) as a repair mechanism after injury may offer a unique strategy to restore both mitochondrial and organ function. Rats subjected to bilateral renal pedicle ligation for 22 min were treated once daily with the SIRT1 activator SRT1720 (5 mg/kg) starting 24 h after reperfusion until 72 h–144 h. SIRT1 expression was elevated in the renal cortex of rats after I/R + vehicle treatment (IRV), but was associated with less nuclear localization. SIRT1 expression was even further augmented and nuclear localization was restored in the kidneys of rats after I/R + SRT1720 treatment (IRS). PGC-1α was elevated at 72 h–144 h in IRV and IRS kidneys; however, SRT1720 treatment induced deacetylation of PGC-1α, a marker of activation. Mitochondrial proteins ATP synthase β, COX I, and NDUFB8, as well as mitochondrial respiration, were diminished 24 h–144 h in IRV rats, but were partially or fully restored in IRS rats. Urinary kidney injury molecule-1 (KIM-1) was persistently elevated in both IRV and IRS rats; however, KIM-1 tissue expression was attenuated in IRS rats. Additionally, sustained loss of Na{sup +},K{sup +}–ATPase expression and basolateral localization and elevated vimentin in IRV rats was normalized in IRS rats, suggesting restoration of a differentiated, polarized tubule epithelium. The results suggest that SRT1720 treatment expedited recovery of mitochondrial protein expression and function by enhancing MB, which was associated with faster proximal tubule repair. Targeting MB may offer unique therapeutic strategy following ischemic injury. - Highlights: • We examined recovery of mitochondrial and renal function after ischemia–reperfusion. • SRT1720 treatment after I/R induced mitochondrial biogenesis via SIRT1/PGC-1α. • Recovery of mitochondrial function was

  8. Comprehensive renal scintillation procedures in spinal cord injury: comparison with excretory urography

    SciTech Connect

    Lloyd, L.K.; Dubovsky, E.V.; Bueschen, A.J.; Witten, D.M.; Scott, J.W.; Kuhlemeier, K.; Stover, S.L.

    1981-07-01

    A /sup 131/iodine orthoiodohippurate comprehensive renal scintillation procedure was performed and compared to results of excretory urography in 200 spinal cord injury patients. No severe urographic abnormalities were undetected by the comprehensive renal scintillation procedure. Only 1.4 per cent of renal units had greater than minimal pyelocaliectasis or ureterectasis in the presence of a normal radionuclide examination. A relatively large number of abnormalities were detected on the renal scintillation procedure when the excretory urogram was normal. Serial followup will be required to determine the significance of these findings but present data suggest that a comprehensive renal scintillation procedure and a plain film of the kidneys, ureters and bladder may be used for screening upper urinary tract abnormalities in lieu of an excretory urogram. This is particularly advantageous for the spinal cord injury population, since there have been no toxic or allergic reactions reported, no bowel preparation or dehydration is required and there is relatively low radiation exposure.

  9. Renal and urological diseases of the newborn neonatal acute kidney injury.

    PubMed

    Mistry, Kirtida

    2014-01-01

    Survival of critically ill neonates in the intensive care unit has improved over the past decades reflecting improvements in obstetric, delivery room and neonatal intensive care, however, morbidity remains significant. Acute kidney injury is a common occurrence in these neonates and despite improved understanding of the pathophysiology and management of acute kidney injury in full term and preterm infants, the mortality remains as high as 61%. Furthermore, there is growing evidence that despite recovery from the acute injury, these infants are at risk for developing hypertension and chronic kidney disease later in life. Emphasis on improving our capability to detect renal insult and injury early, before renal failure occurs, and identification of novel therapeutic agents to prevent and treat acute kidney injury may impact mortality and morbidity. This review focuses on our current knowledge of acute kidney injury in the newborn, approaches to investigating and managing this complication and what future trends in this field may bring. PMID:25088261

  10. Protective effect of ischemic preconditioning on the jejunal graft mucosa injury during cold preservation.

    PubMed

    Jonecova, Zuzana; Toth, Stefan; Maretta, Milan; Ciccocioppo, Rachele; Varga, Jan; Rodrigo, Luis; Kruzliak, Peter

    2015-10-01

    Protection of intestinal graft mucosa during cold preservation is still an unmet need in clinical practice, thus affecting the success of transplantation. The present study investigates the ability of two ischemic preconditioning (IPC) procedures to limit cold preservation injury. Three groups of Sprague-Dawley rats were recruited (n=11 each) as follows: the short IPC (SIPC) performed through 4 cycles of mesenteric ischemia of 4 min each followed by 10 min of reperfusion, the long IPC (LIPC) obtained by 2 ischemic cycles of 12 min each followed by 10 min of reperfusion, and the control group (C) without IPC. Grafts were then stored in cold histidine-tryptophan-ketoglutarate solution and samples were taken at 0, 3, 6 and 9 h lasting preservation. Both IPC groups showed an advanced degree of preservation with delayed development of graft mucosa damage, mainly in the crypt region. At the beginning of preservation, the graft mucosa in both IPC groups showed lower degree of mucosal injury index (MII) by 50% in comparison with C group. Specifically, a significant improvement of MII was observed after 3h of preservation in the LIPC group (p<0.05) in comparison with untreated C grafts. Significant atrophy of the intestinal mucosa in C group was found after 3h of preservation (p<0.01), in SIPC group the progress of atrophy was delayed to 6 h (p<0.001), and in LIPC group only moderate decrease in that was found. A parallel increase of laminin expression with the MII rate after 6 and 9h of preservation in comparison with the level at time 0 was observed in all grafts (p<0.001 and p<0.01, respectively). In both IPC groups the apoptotic cell (AC) rate was significantly reduced at the beginning of cold preservation (p<0.05 both). Moreover, in both the SIPC and C groups, the progressive increase in MII rate connected with AC rate decrease was due to a predominance of necrosis. By contrast in the LIPC group, after an increase of nearly 50% in the AC rate at the 3rd hour, its level