The Protective Effect of A Short Peptide Derived From Cold-Inducible RNA-Binding Protein in Renal Ischemia-Reperfusion Injury.
ABSTRACT: Extracellular cold-inducible RNA-binding protein (CIRP) functions as damage-associated molecular pattern and has been demonstrated to be responsible in part for the damage occurring after renal ischemia-reperfusion (I/R). A short peptide derived from CIRP, named C23, binds to myeloid differentiation factor 2, a Toll-like receptor 4 coreceptor. We hypothesize that C23 reduces renal ischemia-reperfusion (RIR) injury by blocking CIRP. We observed that pretreatment with C23 significantly decreased the levels of recombinant mouse CIRP-induced tumor necrosis factor-? (TNF-?) in a dose-dependent fashion in cultured macrophages. C57BL/6 mice were subjected to bilateral renal pedicle clamps for 35?min to induce ischemia, followed by reperfusion for 24 h and harvest of blood and renal tissue. C23 peptide (8?mg/kg) or vehicle was injected intraperitoneally at the beginning of reperfusion. Plasma TNF-?, interleukin 1 beta (IL-1?), and IL-6 levels were decreased in C23-treated RIR mice as compared with vehicle-treated mice by 74%, 85%, and 68%, respectively. Expressions of TNF-? and keratinocyte chemoattractant in the kidneys from C23-treated mice were decreased by 55% and 60%, respectively. Expression of kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin in the kidney of C23-treated mice were significantly reduced by 46% and 55%, respectively. Renal tissue histological assessments revealed significant reduction in damage score by 44% in C23-treated mice. Finally, a survival study revealed a significant survival advantage with a 70% survival rate in C23 group vs. 37% in vehicle group. Thus, C23 has potential as a novel therapy for the patients suffering from I/R-induced renal injury.
Project description:Cold-inducible RNA-binding protein (CIRP) is a novel sepsis inflammatory mediator and C23 is a putative CIRP competitive inhibitor. Therefore, we hypothesized that C23 can ameliorate sepsis-associated injury to the lungs and kidneys. First, we confirmed that C23 dose-dependently inhibited TNF-? release, I?B? degradation, and NF-?B nuclear translocation in macrophages stimulated with CIRP. Next, we observed that male C57BL/6 mice treated with C23 (8?mg/kg BW) at 2?h after cecal ligation and puncture (CLP) had lower serum levels of LDH, ALT, IL-6, TNF-?, and IL-1? (reduced by ?39%) at 20?h after CLP compared with mice treated with vehicle. C23-treated mice also had improved lung histology, less TUNEL-positive cells, lower serum levels of creatinine (34%) and BUN (26%), and lower kidney expression of NGAL (50%) and KIM-1 (86%). C23-treated mice also had reduced lung and kidney levels of IL-6, TNF-?, and IL-1?. E-selectin and ICAM-1 mRNA was significantly lower in C23-treated mice. The 10-day survival after CLP of vehicle-treated mice was 55%, while that of C23-treated mice was 85%. In summary, C23 decreased systemic, lung, and kidney injury and inflammation, and improved the survival rate after CLP, suggesting that it may be developed as a new treatment for sepsis.
Project description:Renal ischemia-reperfusion (RIR) injury is a common occurrence after major surgery and shock, leading to acute kidney injury (AKI). Osteopontin (OPN) is a secreted glycoprotein that acts as a proinflammatory cytokine and activator of T lymphocytes. We hypothesized that blockade of OPN reduces the severity of inflammation and injury in RIR. Renal ischemia was induced in adult C57BL/6 mice via bilateral clamping of renal pedicles for 35?min, followed by reperfusion for 24?h. Anti-OPN antibody (Ab), nonimmunized isotype immunoglobulin G, or normal saline was injected intravenously at the time of reperfusion. Blood and kidneys were collected for analysis. At 24?h after RIR, OPN mRNA and protein levels were significantly increased in renal tissue compared with sham mice. In serum, elevated levels of blood urea nitrogen and creatinine were reduced in anti-OPN Ab-treated mice compared with vehicle. Anti-OPN Ab-treated mice also had decreased mRNA levels of injury markers neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 compared with the vehicle. The histologic architecture and apoptosis of renal tissue were improved in the anti-OPN Ab-treated mice. In renal tissue, inflammatory cytokines interleukin 6 and tumor necrosis factor-? protein levels were reduced in the Ab-treated mice. Natural killer (NK) cell infiltration was decreased after anti-OPN Ab treatment, as was neutrophil infiltration, shown by reduced chemokine expression and Gr1 renal immunohistochemical staining. These findings demonstrate a beneficial role of OPN blockade in RIR associated with NK cell-mediated downregulation of inflammatory cytokines and chemokines. Administration of anti-OPN Ab may therefore serve as an immunomodulatory adjunct in the treatment of RIR-induced AKI.
Project description:BACKGROUND:Hemorrhagic shock (HS) is an important cause of mortality. HS is associated with an elevated incidence of acute lung injury and acute respiratory distress syndrome, significantly contributing to HS morbidity and mortality. Cold-inducible RNA-binding protein (CIRP) is released into the circulation during HS and can cause lung injury. C23 is a CIRP-derived oligopeptide that binds with high affinity to the CIRP receptor and inhibits CIRP-induced phagocyte secretion of TNF-?. This study was designed to determine whether C23 is able to attenuate HS-associated lung injury. METHODS:C57BL/6 mice were subjected to controlled hemorrhage leading to a mean arterial pressure of 25 ± 3 mm Hg for 90 minutes. Mice were then volume-resuscitated for 30 minutes with normal saline solution alone (vehicle) or plus adjuvant treatment with C23 (8 mg/kg BW). At 4.5 hours after resuscitation, the blood and lungs were harvested. RESULTS:Serum levels of organ injury markers lactate dehydrogenase, aspartate aminotransferase were significantly elevated in hemorrhaged mice receiving vehicle and were reduced by 51.3% and 52.2% in mice adjuvantly treated with C23, respectively. Similarly, lung mRNA levels of IL-1?, TNF-?, and IL-6, and lung myeloperoxidase activity were elevated after HS and reduced by 66.1%, 54.4%, 69.7%, and 24.3%, respectively, in mice treated with C23. Adjuvant treatment with C23 also decreased the lung histology score by 33.9%, lung extravasation of albumin carrying Evans blue dye by 36.8%, and the protein level of intercellular adhesion molecule-1, and indicator of vascular endothelial cell activation, by 40.3%. CONCLUSION:Together, these results indicate that adjuvant treatment with the CIRP-derived oligopeptide C23 is able to improve lung inflammation and vascular endothelial activation secondary to HS, lending support to the development of CIRP-targeting adjuvant treatments to minimize lung injury after HS.
Project description:INTRODUCTION:Neonatal sepsis remains a leading cause of infant mortality. Cold-inducible RNA binding protein (CIRP) is an inflammatory mediator that induces TNF-? production in macrophages. C23 is a CIRP-derived peptide that blocks CIRP from binding its receptor. We therefore hypothesized that treatment with C23 reduces systemic inflammation and protects the lungs in neonatal sepsis. METHODS:Sepsis was induced in C56BL/6 mouse pups (5-7?days) by intraperitoneal injection of adult cecal slurry (0.525?mg/g body weight, LD100). One hour later pups received retroorbital injection of C23 (8?mg/kg) or vehicle (normal saline). Ten hours after sepsis induction, blood and tissues were collected for analysis. RESULTS:C23 treatment resulted in a 58% and 69% reduction in serum levels of proinflammatory cytokines IL-6 and IL-1?, respectively, and a 40% and 45% reduction of AST and LDH, as compared to vehicle-treated septic pups. In the lungs, C23 treatment reduced expression of cytokines IL-6 and IL-1? by 78% and 74%. In addition, the mRNA level of neutrophil chemoattractants KC and MIP-2 was reduced by 84% and 74%, respectively. These results corresponded to a reduction in histologic lung injury score. Vehicle-treated pups scored 0.49?±?0.19, while C23 treatment reduced scores to 0.29?±?0.12 (p?<?0.05; Max?=?1). Apoptosis in the lungs, measured by TUNEL assay, was also decreased by 53% with C23 treatment (p?<?0.05). CONCLUSIONS:Inhibition of CIRP with C23 treatment is protective in septic neonatal mice as demonstrated by reduced inflammatory markers systemically and in the lung. Therefore, C23 has promising therapeutic potential in treatment of neonatal sepsis. LEVEL OF EVIDENCE:Level I.
Project description:PURPOSE:To investigate the effects of grape seed proanthocyanidin B2 (GSPB2) preconditioning on oxidative stress and apoptosis of renal tubular epithelial cells in mice after renal ischemia-reperfusion (RIR). METHODS:Forty male ICR mice were randomly divided into 4 groups: Group A: mice were treated with right nephrectomy. Group B: right kidney was resected and the left renal vessel was clamped for 45 minutes. Group C: mice were intraperitoneally injected with GSPB2 before RIR established. Group D: mice were intraperitoneally injected with GSPB2 plus brusatol before RIR established. Creatinine and urea nitrogen of mice were determined. Pathological and morphological changes of kidney were checked. Expressions of Nrf-2, HO-1, cleaved-caspase3 were detected by Western-blot. RESULTS:Compared to Group B, morphology and pathological damages of renal tissue were less serious in Group C. Western-blot showed that expressions of Nrf-2 and HO-1 in Group C were obviously higher than those in Group B. The expression of cleaved-caspase3 in Group C was significantly lower than that in Group B. CONCLUSION:GSPB2 preconditioning could attenuate renal oxidative stress injury and renal tubular epithelial cell apoptosis by up-regulating expressions of Nrf-2 and HO-1 and down-regulating the expression of cleaved-caspase-3, but the protective effect could be reversed by brusatol.
Project description:RIR leads to ischemic acute kidney injury. Many genes were shown to be altered in this group. Overall design: We used microarrays to detail the global differences of gene expression in the livers of male wild-type mice subjected to 30 minutes of warm renal ischemia reperfusion injury (RIR) in comparison to livers of male wild-type mice subjected to sham surgery.
Project description:EST KO mice are protected from ischemic acute kidney injury (AKI). Many genes were shown to be altered in this group. Overall design: We used microarrays to detail the global differences of gene expression in the kidneys of male EST KO mice subjected to 30 minutes of warm renal ischemia reperfusion injury (RIR) in comparison to kidneys of male wild-type mice subjected to RIR.
Project description:Renal ischemia-reperfusion injury causes acute renal failure, and the hallmarks of renal ischemia-reperfusion injury are inflammation, apoptosis, necrosis, and capillary dysfunction. Milk fat globule-epidermal growth factor-factor VIII (MFG-E8), a membrane-associated secretory glycoprotein, is produced by immune cells and reported to participate in multiple physiologic processes associated with tissue remodeling. We have recently shown that MFG-E8 treatment attenuates organ injury, inflammatory responses, and survival after sepsis through the enhancement of phagocytosis of apoptotic cells. The purpose of this study was to determine whether administration of MFG-E8 attenuates renal ischemia-reperfusion injury.Prospective, controlled, and randomized animal study.: A research institute laboratory.Male C57BL/6J mice (20-25 g).: Renal ischemia-reperfusion injury with bilateral renal pedicle clamping for 45 mins, followed by reperfusion. A recombinant murine MFG-E8 (0.4 ?g/20 g) was given intraperitoneally at the beginning of reperfusion.MFG-E8 levels, organ injury variables, inflammatory responses, histology, apoptosis, and capillary functions were assessed at 1.5 and 20 hrs after reperfusion. A 60-hr survival study was conducted in MFG-E8 and recombinant murine MFG-E8-treated wild-type mice. After renal ischemia-reperfusion injury, MFG-E8 mRNA and protein expressions were significantly decreased in the kidneys and spleen. Treatment with recombinant murine MFG-E8 recovered renal dysfunction, significantly suppressed inflammatory responses, apoptosis, necrosis, and improved capillary functions in the kidneys. In the survival study, MFG-E8 mice showed a significant deterioration and, in contrast, recombinant murine MFG-E8-treated wild-type mice showed a significant improvement of survival compared with vehicle-treated wild-type mice.MFG-E8 can be developed as novel treatment for renal ischemia-reperfusion injury. This protective effect appears to be mediated through the enhancement of apoptotic cell clearance and improvement of capillary functions in the kidneys.
Project description:Acute kidney injury (AKI) induced by ischemia-reperfusion is a critical conundrum in many clinical settings. Here, this study aimed to determine whether and how RTA-408, a novel oleanane triterpenoid, could confer protection against renal ischemia-reperfusion injury (IRI) in male mice. Mice treated with RTA-408 undergoing unilateral ischemia followed by contralateral nephrectomy had improved renal function and histological outcome, as well as decreased apoptosis, ROS production, and oxidative injury marker compared with vehicle-treated mice. Also, we had found that RTA-408 could strengthen the total antioxidant capacity by increasing Nrf2 nuclear translocation and subsequently increased Nrf2 downstream GSH-related antioxidant gene expression and activity. In vitro study demonstrated that GSH biosynthesis enzyme GCLc could be an important target of RTA-408. Furthermore, Nrf2-deficient mice treated with RTA-408 had no significant improvement in renal function, histology, ROS production, and GSH-related gene expression. Thus, by upregulating Nrf2 and its downstream antioxidant genes, RTA-408 presents a novel and potential approach to renal IRI prevention and therapy.
Project description:RIR leads to ischemic acute kidney injury (AKI). Women below the age of menopause have a lower incidence of AKI. It is bellieved that estrogens are protective. Many genes were shown to be altered in female wild-type mice subjected to IRI. Overall design: We used microarrays to detail the global differences of gene expression in the livers of female wild-type mice subjected to 30 minutes of warm renal ischemia reperfusion injury (RIR) in comparison to livers of female wild-type mice subjected to sham surgery.