Renal Tubular Damage Score Research Articles

Valproic acid treatment attenuates cisplatin-induced kidney injury by suppressing proximal tubular cell damage.

Cisplatin treatment is effective against several types of carcinomas. However, it frequently leads to kidney injury, which warrants effective prevention methods. Sodium valproic acid is a prophylactic drug candidate with a high potential for clinical application against cisplatin-induced kidney injury. Therefore, in this study, we aimed to elucidate the mechanism underlying the prophylactic effect of valproic acid on cisplatin-induced kidney injury in a mouse model and HK2 and PODO cells with cisplatin-induced toxicity. In the mouse model of cisplatin-induced kidney injury, various renal function parameters and tubular damage scores were worsened by cisplatin, but they were significantly improved upon combination with valproic acid. No difference was observed in cisplatin accumulation between the cisplatin-treated and valproic acid-treated groups in whole blood and the kidneys. The mRNA expression levels of proximal tubular damage markers, apoptosis markers, and inflammatory cytokines significantly increased in the cisplatin group 72 h after cisplatin administration but significantly decreased upon combination with valproic acid. In HK2 cells, a human proximal tubular cell line, the cisplatin-induced decrease in cell viability was significantly suppressed by co-treatment with valproic acid. Valproic acid may inhibit cisplatin-induced kidney injury by suppressing apoptosis, inflammatory responses, and glomerular damage throughout the kidneys by suppressing proximal tubular cell damage. However, prospective controlled trials need to evaluate these findings before their practical application.

Rhizophora apiculata Bark Ethanolic Extracts Prevent Kidney Damage Caused by Cigarette Smoke in Male Rats

Rhizophora apiculata mangrove bark contains high levels of antioxidants, including triterpenoids, steroids, saponins, and tannins. The high antioxidant content can prevent oxidative stress, one of which is caused by free radicals from cigarette smoke. This research aimed to determine the potential of Rhizophora apiculata mangrove bark to protect against damage to the kidney organs of male white rats (Rattus novergicus) of the Sprague-Dawley strain exposed to cigarette smoke. This study used 25 mice divided into 5 groups for 30 days, namely group K(-), which was not given exposure to cigarette smoke and mangrove bark extract; group K(+), which was only given exposure to cigarette smoke; group P1, which was given the extract mangrove bark with a dose of 26.27 mg/kg BW and given exposure to cigarette smoke 24 cigarettes per day, group P2 which was given mangrove bark extract with a dose of 56.55 mg/kg BW and given exposure to cigarette smoke 24 cigarettes per day, and group P3 which was given mangrove oil bark extract at a dose of 113.1 mg/kg BW and given exposure to cigarette smoke 24 cigarettes per day. On day 31, the rats were euthanized, and their kidneys were prepared for histology. Kidney histology was observed, and kidney damage was assessed from the histology of glomerular and renal tubular damage. The kidney damage score is 0 if there was no damage, 1 if inflammatory cell infiltration was found, 2 if Bowman space edema or swelling of tubular epithelial cells was found, 3 if necrosis was found. Then, take the average of each renal tubular and glomerular damage score and add them together for a total damage score, namely 0-6. The median kidney damage score in the K (-) group was 0.4, the K (+) group was 3.6, the P1 group was 2.4, the P2 group was 2.4, and the P3 group was 2.2. The results of the Kruskal-Wallis test obtained a p-value of 0.001, meaning there were significant differences in at least the two treatment groups. This research showed that administering Rhizophora apiculata mangrove bark extract could prevent histological damage to the kidneys of male white rats of the Sprague-Dawley strain caused by cigarette smoke.

The Effect of VPA Treatment on Radiolabeled DOTATATE Uptake: Differences Observed In Vitro and In Vivo

Background: To improve peptide receptor radionuclide therapy (PRRT), we aimed to enhance the expression of somatostatin type-2 receptors (SSTR2) in vitro and in vivo, using valproic acid (VPA). Methods: Human NCI-H69 small-cell lung carcinoma cells were treated with VPA, followed by [111In]In-DOTATATE uptake studies, RT-qPCR and immunohistochemistry analysis. Furthermore, NCI-H69 xenografted mice were treated with VPA or vehicle, followed by [177Lu]Lu-DOTATATE injection. Biodistribution studies were performed, and tissues were collected for further analysis. Results: VPA significantly increased SSTR2 expression in vitro. In animals, a statistically significant increased [177Lu]Lu-DOTATATE tumoral uptake was observed when VPA was administered eight hours before [177Lu]Lu-DOTATATE administration, but increased tumor SSTR2 expression levels were lacking. The animals also presented significantly higher [177Lu]Lu-DOTATATE blood levels, as well as an elevated renal tubular damage score. This suggests that the enhanced tumor uptake was presumably a consequence of the increased radiotracer circulation and the induced kidney damage. Conclusions: VPA increases SSTR2 expression in vitro. In vivo, the observed increase in tumoral [177Lu]Lu-DOTATATE uptake is not caused by SSTR2 upregulation, but rather by other mechanisms, e.g., an increased [177Lu]Lu-DOTATATE circulation time and renal toxicity. However, since both drugs are safely used in humans, the potential of VPA to improve PRRT remains open for investigation.

Effect and mechanism of astaxanthin on acute kidney injury in rats with full-thickness burns

Effect and mechanism of astaxanthin on acute kidney injury in rats with full-thickness burns

Repository corticotropin injection versus corticosteroids for protection against renal damage in a focal segmental glomerulosclerosis rodent model

BackgroundFocal segmental glomerulosclerosis (FSGS) causes renal fibrosis and may lead to kidney failure. FSGS and its common complication, proteinuria, are challenging to treat. Corticosteroids are ineffective in many patients with FSGS, and alternative treatments often yield suboptimal responses. Repository corticotropin injection (RCI; Acthar® Gel), a naturally sourced complex mixture of purified adrenocorticotropic hormone analogs and other pituitary peptides, may have beneficial effects on idiopathic FSGS via melanocortin receptor activation.MethodsTwo studies in a preclinical (female Sprague-Dawley rats) puromycin aminonucleoside FSGS model assessed the effect of RCI on renal function and morphology: an 8-week comparison of a single RCI dose with methylprednisolone (N = 27), and a 12-week chronic RCI dose range study (N = 34). Primary outcomes were proteinuria and renal pathology improvements for measures of renal fibrosis, tubular damage, glomerular injury, and total kidney injury score. Impact of RCI treatment was also determined by assessing urinary biomarkers for renal injury, podocyte expression of podoplanin (a biomarker for injury), podocyte effacement by electron microscopy, and histological staining for fibrosis biomarkers.ResultsCompared with saline treatment, RCI 30 IU/kg significantly reduced proteinuria, with a 38% reduction in peak mean urine protein levels on day 28 in the 8-week model, and RCI 10 IU/kg, 30 IU/kg, and 60 IU/kg reduced peak mean urine protein in the 12-week model by 18, 47, and 44%, respectively. RCI also showed significant dose-dependent improvements in fibrosis, interstitial inflammation, tubular injury, and glomerular changes. Total kidney injury score (calculated from histopathological evaluations) demonstrated statistically significant improvements with RCI 30 IU/kg in the 8-week study and RCI 60 IU/kg in the 12-week study. RCI treatment improved levels of urinary biomarkers of kidney injury (KIM-1 and OPN), expression of podoplanin, and podocyte morphology. RCI also reduced levels of desmin and fibrosis-associated collagen deposition staining. Methylprednisolone did not improve renal function or pathology in this model.ConclusionsThese results provide evidence supporting the improvement of FSGS with RCI, which was superior to corticosteroid treatment in this experimental model. To the authors’ knowledge, this is the first evidence that a drug for the treatment of FSGS supports podocyte recovery after repeated injury.

Effects of dexmedetomidine on renal fibrosis in a mouse model of renal ischemia-reperfusion: the role of Akt

Objective To evaluate the effect of dexmedetomidine on renal fibrosis in a mouse model of renal ischemia-reperfusion (I/R) and the role of serine-threonine kinase (Akt). Methods Sixty male C57BL/6 mice, aged 8 weeks, weighing 20-25 g, were divided into 5 groups (n=12 each) using a random number table method: sham operation group (S group), renal I/R group (I/R group), renal I/R plus dexmedetomidine group (I/R + D group), renal I/R plus dexmedetomidine plus Akt agonist SC79 group (I/R + D + SC group), and renal I/R plus dexmedetomidine plus normal saline group (I/R+ D+ NS group). Renal I/R injury model was established by clamping the bilateral renal pedicle for 30 min followed by reperfusion.Dexmedetomidine was intraperitoneally injected at 30 min before surgery in I/R+ D, I/R+ D+ SC and I/R+ D+ NS groups.SC79 was intraperitoneally injected as a bolus of 0.04 mg/kg at 1 min of reperfusion, followed by an intraperitoneal injection of the same dose every 24 h until day 7.The serum blood urea nitrogen (BUN) and Scr concentrations were detected at 24 h of reperfusion.Renal tissues were taken, and the damage to the renal tubules was scored.Renal tissues were removed at 14 days of reperfusion to detect the degree of renal fibrosis and expression of collagen 1 (COL1), fibronectin (FN), and α-smooth actin (α-SMA) (by immunofluorescence and Western blot). The expression of phosphorylated Akt (p-Akt) in renal tissues was determined by Western blot at 24 h and 14 day of reperfusion. Results Compared with group S, the serum BUN and Scr concentrations, renal tubule damage score and degree of renal fibrosis were significantly increased, and the expression of COL1, FN, α-SMA and p-Akt was up-regulated in group I/R (P<0.05). Compared with I/R group, the serum BUN and Scr concentrations, renal tubular damage score and degree of renal fibrosis were significantly decreased, and the expression of COL1, FN, α-SMA and p-Akt was down-regulated in I/R+ D and I/R+ D+ NS groups (P<0.05). Compared with I/R+ D group, the serum BUN and Scr concentrations, renal tubule damage score and degree of renal fibrosis were significantly increased , and the expression of COL1, FN, α-SMA and p-Akt was up-regulated in I/R+ D+ SC group (P<0.05). Conclusion Dexmedetomidine can reduce the degree of renal fibrosis in a mouse model of renal I/R and the mechanism is related to inhibiting activation of Akt. Key words: Dexmedetomidine; Fibrosis; Kidney; Reperfusion injury; Protein-serine-threonine kinases

Role of HDAC3 in renal injury induced by myocardial ischemia-reperfusion in diabetic rats

Objective To evaluate the role of histone deacetylase 3 (HDAC3) in renal injury induced by myocardial ischemia-reperfusion (I/R) in diabetic rats. Methods SPF healthy adult male Sprague-Dawley rats, weighing 210-220 g, were used in this study.Diabetes mellitus was induced by intraperitoneal injection of 1% streptozotocin 60 mg/kg.Eighteen diabetic rats were divided into 3 groups (n=6 each) using a random number table method: sham operation group (group S), group I/R and HDAC3 inhibitor RGFP966 group (RG). The myocardial I/R model was established by ligation of the left anterior descending coronary artery for 30 min followed by 120-min reperfusion.RGFP966 10 mg/kg was intraperitoneally injected at 1 h before myocardial ischemia in group RG.The right internal carotid artery was isolated at 120 min of reperfusion for measurement of serum lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), creatinine (Cr) and urea nitrogen concentrations.Renal tissues were obtained for examination of the pathological changes and for determination of the expression of HDAC3, silent information regulator 1 (SIRT1) and interleukin-1β (IL-1β). The damage to the renal tubules was scored. Results Compared with S group, the serum LDH, CK-MB, Cr and urea nitrogen concentrations and renal tubular damage score were significantly increased, the expression of HDAC3 and IL-1β was up-regulated, and the expression of SIRT1 was down-regulated in group I/R (P<0.05). Compared with group I/R, the serum LDH, CK-MB, Cr and urea nitrogen concentrations and renal tubular damage score were significantly decreased, the expression of HDAC3 and IL-1β was down-regulated, and the expression of SIRT1 was up-regulated in group RG (P<0.05). Conclusion Up-regulated expression of HDAC3 is involved in renal injury induced by myocardial I/R in diabetic rats. Key words: Histone deacetylases; Diabetes mellitus; Myocardial reperfusion injury; Acute kidney injury

Effect of resveratrol on mitochondrial function in renal tubular epithelial cells of rats with sepsis-induced acute kidney injury

Objective To evaluate the effect of resveratrol on mitochondrial function in renal tubular epithelial cells of rats with sepsis-induced acute kidney injury. Methods Ninety-six healthy Sprague-Dawley rats of both sexes, aged 5-7 weeks, weighing 180-220 g, were divided into 4 groups (n=24 each) using a random number table method: sham operation group (Sham group), sepsis group (group Sep), sepsis plus vehicle group (Sep+ V group) and sepsis plus resveratrol group (Sep+ R group). Sepsis was induced by cecal ligation and puncture (CLP). Normal saline 0.5 ml, vehicle 0.5 ml and resveratrol 10 mg/kg were intraperitoneally injected at 6, 12 and 18 h after CLP in Sep, Sep+ V and Sep+ R groups, respectively.At 24 h after CLP, serum concentrations of creatinine (Cr) and blood urea nitrogen (BUN) were measured, and kidney tissues were obtained for examination of the pathological changes (using transmission electron microscopy), and the damage to the renal tubules was scored.The renal tubular epithelial cells (RTECs) were isolated from the kidney cortex at 24 h after CLP for determination of mitochondrial transmembrane potential (by flow cytometry with the fluorescent probe JC-1), intracellular ATP content, mitochondrial permeability transition pore (mPTP) opening, lipid peroxide (LPO) content, and lysosomal membrane permeability. Results Compared with group Sham, the serum concentrations of Cr and BUN, renal tubular damage score, mPTP opening, LPO content and lysosomal membrane permeability were significantly increased, and mitochondrial transmembrane potential and ATP content were decreased in Sep and Sep+ V groups (P<0.01). Compared with Sep and Sep+ V groups, the serum concentrations of Cr and BUN, renal tubular damage score, mPTP opening, LPO content and lysosomal membrane permeability were significantly decreased, and mitochondrial transmembrane potential and ATP content were increased in group Sep+ R (P<0.05). Conclusion Resveratrol improves mitochondrial function in renal tubular epithelial cells of rats with sepsis and reduces acute kidney injury, and the mechanism may be related to inhibiting oxidative stress and decreasing the lysosomal membrane permeability. Key words: Phenols; Sepsis; Acute kidney injury; Mitochondria; Kidney tubules; Epithelial cells

Role of SIRT3/FOXO3α signaling pathway in dexmedetomidine-induced reduction of hepatic ischemia-reperfusion injury in mice

Objective To evaluate the role of sirtuin 3 (SIRT3)/forkhead box O3α (FOXO3α) signaling pathway in dexmedetomidine-induced reduction of hepatic ischemia-reperfusion (I/R) injury in mice. Methods Forty clean-grade C57BL/6 mice of both sexes, aged 2 weeks, weighing 6-8 g, were divided into 4 groups (n=10 each) using a random number table method: sham operation group (group S), hepatic I/R group (group I/R), dexmedetomidine group (group D) and SIRT3 inhibitor 3-TYP plus dexmedetomidine group (group T+ D). Portal vein and hepatic artery supplying left and middle lobes of the liver and biliary tract were clamped resulting in ischemia of 70% of the liver in anesthetized rats.Normal saline 0.25 ml was intraperitoneally injected at 1 h before establishing model, and 30 min later dexmedetomidine 50 μg/kg (diluted to 0.25 ml in normal saline) was intraperitoneally injected in group D. In group T+ D, 3-TYP 5 mg/kg (diluted to 0.25 ml in normal saline) was intraperitoneally injected at 1 h before establishing model, and 30 min later dexmedetomidine 50 μg/kg (diluted to 0.25 ml in normal saline) was intraperitoneally injected.Mice were selected at 6 h after reperfusion, blood samples were obtained through eyeball, and the mice were then sacrificed and kidneys were removed for determination of the serum concentrations of creatinine (Cr) and blood urea nitrogen (BUN), cell apoptosis (by TUNEL), malondialdehyde (MDA) content (using thiobarbituric acid method), superoxide dismutase (SOD) activity (by xanthine oxidase method), and acetylation of FOXO3α in renal tissues (by using immunoprecipitation) and for examination of the pathologic changes.The damage to renal tubules was scored.Apoptosis index (AI) was calculated. Results Compared with group S, the renal tubular damage score and AI were significantly increased, serum concentrations of Cr and BUN were increased, the content of MDA was increased, the activity of SOD was decreased, and the acetylation of FOXO3α was decreased in I/R, D and T+ D groups (P 0.05). Compared with group D, the renal tubular damage score and AI were significantly increased, serum concentrations of Cr and BUN were increased, the content of MDA was increased, the activity of SOD was decreased, and the acetylation of FOXO3α was decreased in group T+ D (P<0.05). Conclusion Activation of SIRT3/FOXO3α signaling pathway is involved in dexmedetomidine-induced reduction of hepatic I/R injury in mice. Key words: Dexmedetomidine; Sirtuins; Forkhead transcription factors; Reperfusion injury; Liver; Kidney

Effect of dexmedetomidine on acute kidney injury in septic rats: the relationship with HMGB1 mRNA in renal tissues

Objective To evaluate the effect of dexmedetomidine on acute kidney injury (AKI) and the relationship between the mechanism and expression of high mobility group protein B1 (HMGBl) mRNA in renal tissues of septic rats. Methods Fort-eight healthy adult male Sprague-Dawley rats, aged 8-12 weeks, weighing 240-270 g, were divided into 3 groups (n=16 each) using a random number table method: control group (C group), sepsis group (S group ) and dexmedetomidine group (D group). AKI was induced by cecal ligation and puncture.The concentrations of serum cystatin C (Cys C) were measured by immunoturbidimetry at 24 and 48 h after operation.The rats were sacrificed after blood sampling, and kidney tissues were removed for determination of the expression of HMGB1 mRNA (by fluorescent quantitative real-time polymerase chain reaction) and for examination of the pathological changes.The damage to the renal tubules was scored. Results Compared with group C, the renal tubular damage score and serum Cys C concentrations were significantly increased, and the expression of HMGB1 mRNA was up-regulated in S and D groups (P<0.05). Compared with group S, the renal tubular damage score and serum Cys C concentrations were significantly decreased, the expression of HMGB1 mRNA was down-regulated (P<0.05), and the pathological changes of renal tissues were significantly attenuated in group D. Conclusion Dexmedetomidine can attenuate AKI in septic rats and the mechanism may be related to inhibiting the expression of HMGB1 mRNA in renal tissues. Key words: Dexmedetomidine; Sepsis; Kidney; High mobility group proteins

Role of Nrf2 signaling pathway in attenuation of ischemia injury by hydrogen-rich University of Wisconsin solution during cold storage of rat donor kidneys

Objective To evaluate the role of nuclear factor erythroid 2-related factor 2(Nrf2)signaling pathway in attenuation of ischemia injury by hydrogen-rich University of Wisconsin(HRUW)solution during cold storage of rat donor kidneys. Methods Forty healthy adult male Wistar rats, weighing 200-250 g, were divided into 4 groups(n=10 each)using a random number table: control group(group C), University of Wisconsin(UW)solution group(group UW), HRUW solution group(group HRUW)and Nrf2 inhibitor all-trans retinoic acid(ATRA)group(group ATRA). ATRA 7 mg/kg was intraperitioneally injected once a day for 2 consecutive days, kidneys were isolated and underwent cold storage at 8 h after the last administration, and kidneys were stored in HRUW solution for 48 h at 4 ℃ in group ATRA.In UW and HRUW groups, the equal volume of normal saline was intraperitioneally injected instead, and isolated kidneys were stored in UW solution and HRUW solution for 48 h at 4 °C, respectively.Kidney specimens were obtained for microscopic examination and for determination of tumor necrosis factor-alpha(TNF-α), interleukin-1beta(IL-1β), high-mobility group box 1 protein(HMGB1), IL-10 and 8-iso-prostaglandin F2α(8-iso-PGF2α)contents(by enzyme-linked immunosorbent assay), superoxide dismutase(SOD)and catalase(CAT)activities(using spectrophotometry), and expression of Nrf2, heme oxygenase-1(HO-1), Bcl-2, Bax and caspase-3 in renal tissues(by using Western blot). The damage to the renal tubules was scored. Results Compared with group C, renal tubular damage scores were significantly increased, TNF-α, IL-1β, HMGB1 and 8-iso-PGF2α contents were increased, IL-10 contents were decreased, the expression of Nrf2 and HO-1 was up-regulated, SOD and CAT activities were decreased, the expression of Bcl-2 was down-regulated, and the expression of Bax and caspase-3 was up-regulated in group UW(P 0.05). Compared with group HRUW, renal tubular damage scores were significantly increased, TNF-α, IL-1β, HMGB1 and 8-iso-PGF2α contents were increased, IL-10 contents were decreased, the expression of HO-1 and Bcl-2 was down-regulated, SOD and CAT activities were decreased, and the expression of Bax and caspase-3 was up-regulated in group ATRA. Conclusion HRUW solution reduces inflammatory responses, oxidative damage and cell apoptosis during cold storage of rat donor kidneys, and the mechanism by which HRUW solution attenuates ischemia injury is related to activation of Nrf2 signaling pathway. Key words: Hydrogen; NF-E2 related factor 2; Kidney transplantation; Cryopreservation; Cold ischemia

Dexmedetomidine protects against cisplatin-induced acute kidney injury in mice through regulating apoptosis and inflammation.

Cisplatin-based chemotherapy has been widely used in the perioperative period of cancer surgery, which exacerbates the risk of renal injury. In this study, we examined whether dexmedetomidine (DEX), a commonly used anesthetic adjuvant, shows a protective effect against cisplatin-induced acute kidney injury. Acute kidney injury in mice was induced by cisplatin. Mice were administered with DEX 25μg/kg or atipamezole 250μg/kg (once a day, for 3days) after cisplatin treatment. The renal function and tubular damage score were evaluated at 72h following cisplatin administration. Apoptotic tubular cells were detected by TUNEL assay. Caspase-3, p53, Bax, F4/80+ macrophages, CD3+ T cells, and NF-κB were examined by immunohistochemistry staining or Western blot. Tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and monocyte chemoattractant protein (MCP)-1 in kidney were measured using real-time polymerase chain reaction. DEX treatment preserved renal function and reduced tubular damage score of mice after cisplatin administration. Mice treated with DEX exhibited less apoptotic tubular cells in response to cisplatin insult, which was associated with decreased Bax and reduced activation of p53 and caspase-3. DEX suppressed the infiltration of macrophages and T cells into the kidneys following cisplatin treatment, which was involved in the inhibition of NF-κB activation and decreased expression of TNF-α, IL-1β, IL-6, and MCP-1. Furthermore, we showed that the renoprotective effect conferred by DEX may be related to α2 adrenoceptor-dependent pathway. We demonstrate that DEX protects the kidney against cisplatin-induced AKI by the regulation of apoptosis and inflammatory response.

Effect of penehyclidine hydrochloride pretreatment on Nrf2/HO-1 signaling pathway in renal tissues of rats with rhabdomyolysis-induced acute kidney injury

Objective To investigate the effect of penehyclidine hydrochloride (PHC) pretreatment on nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) signaling pathway in renal tissues of rats with rhabdomyolysis-induced acute kidney injury (AKI). Methods Thirty-six pathogen-free male Sprague-Dawley rats, weighing 200-220 g, were assigned into 3 groups (n=12 each) using a random number table: control group (group C), group AKI and PHC pretreatment group(group PHC). Rhabdomyolysis was induced by intramuscular injection of 50% glycerol 10 ml/kg in bilateral hindlimbs.PHC 0.2 mg/kg was injected intraperitoneally at 30 min before glycerol was injected intramuscularly in group PHC.At 1 and 6 h after glycerol injection, serum was collected for determination of blood urea nitrogen(BUN) and creatinine(Cr) concentrations, and bilateral kidneys were harvested for pathological examination and for determination of HO-1 activity and expression of Nrf2 mRNA and HO-1 mRNA (by quantitative real-time polymerase chain reaction), Nrf2 in nucleoprotein and total protein and HO-1 in total protein in renal tissues (by Western blot). The damage to the renal tubules was scored. Results Compared with group C, the BUN and Cr concentrations in serum and renal tubular damage scores were significantly increased, the expression of Nrf2 in nucleoprotein and total protein and HO-1 in total protein was significantly up-regulated, and HO-1 activity was significantly increased in AKI and PHC groups, the expression of HO-1 mRNA was significantly up-regulated in group AKI, and the expression of Nrf2 mRNA and HO-1 mRNA was significantly up-regulated in group PHC (P<0.01 or 0.05). Compared with group AKI, the BUN and Cr concentrations in serum and renal tubular damage scores were significantly decreased, the expression of Nrf2 in nucleoprotein and total protein and HO-1 in total protein was significantly up-regulated, and HO-1 activity was significantly increased in group PHC (P<0.01 or 0.05). Conclusion The mechanism by which PHC pretreatment attenuates rhabdomyolysis-induced AKI may be related to activation of Nrf2/HO-1 signaling pathway in renal tissues of rats. Key words: Penehyclidine hydrochloride; Rhabdomyolysis; Kidney; Nuclear factor erythroid 2-related factor 2; Heme oxygenase-1

Role of Nrf2/HO-1 signaling pathway in reduction of acute kidney injury following orthotopic liver transplantation by hydrogen-rich saline in rats

Objective To investigate the role of nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)signaling pathway in reduction of acute kidney injury following orthotopic liver transplantation(OLT)by hydrogen-rich saline in rats. Methods Thirty-two healthy adult male Sprague-Dawley rats, weighing 220-250 g, were randomly assigned into 4 groups(n=8 each)using a random number table: sham operation group(S group), OLT group, hydrogen-rich saline group(HS group), and all-trans retinoic acid(ATRA)group.Laparotomy was performed, and the related blood vessels were isolated in group S. The model of orthotopic autologous liver transplantation was established in OLT, HS and ATRA groups.Normal saline and hydrogen-rich saline 6 ml/kg were injected through the inferior vena cava at 5 min before the portal vein was clamped in OLT and HS groups, respectively.In group ATRA, Nrf2 inhibitor ATRA 7 mg/kg was injected intraperitoneally once a day for 2 consecutive days, the model of orthotopic autologous liver transplantation was established at 16 h after the last injection of ATRA, and the other treatments were similar to those previously described in group HS.At 6 h of reperfusion, blood samples were collected for determination of serum blood urea nitrogen(BUN), creatinine(Cr), interleukin-10(IL-10)and tumor necrosis factor-alpha(TNF-α)concentrations.After blood sampling, the lungs were removed for determination of malondialdehyde(MDA)content, superoxide dismutase(SOD)activity, expression of HO-1, Bcl-2 and Bax mRNA(by using real-time reverse transcriptase polymerase chain reaction), and HO-1 protein expression in lung tissues(by Western blot)and for microscopic examination.The damage to the renal tubules was scored. Results Compared with group S, the serum BUN, Cr and TNF-α concentrations were significantly increased, the serum IL-10 concentrations were decreased, the MDA content and renal tubular damage score were increased, the SOD activity was decreased, and the expression of HO-1 protein and mRNA, and Bcl-2 and Bax mRNA was up-regulated in group OLT(P<0.05). Compared with group OLT, the serum BUN, Cr and TNF-α concentrations were significantly decreased, the serum IL-10 concentrations were increased, the MDA content and renal tubular damage score were decreased, the SOD activity was increased, the expression of HO-1 protein and mRNA and Bcl-2 mRNA was up-regulated, and the expression of Bax mRNA was down-regulated in group HS(P<0.05). Compared with group HS, the serum BUN, Cr and TNF-α concentrations were significantly increased, the serum IL-10 concentrations were decreased, the MDA content and renal tubular damage score were increased, the SOD activity was decreased, the expression of HO-1 protein and mRNA and Bcl-2 mRNA was down-regulated, and the expression of Bax mRNA was up-regulated in group ATRA(P<0.05). Conclusion The mechanism by which hydrogen-rich saline reduces acute kidney injury following OLT is probably associated with activation of Nrf2/HO-1 signaling pathway in rats. Key words: Hydrogen; NF-E2-related factor 2; Heme oxygenase-1; Liver transplantation; Kidney injury

Role of chemokine CXC-ligand 16 in renal ischemia-reperfusion injury in mice

Objective To investigate the role of chemokine CXC-ligand 16 (CXCL16) in renal ischemia-reperfusion (I/R) injury in the mice. Methods Twelve healthy male C57BL/6 mice and 12 CXCL16-knockout (CXCL16-KO) mice, aged 8-10 weeks, weighing 20-30 g, were studied.The 12 C57BL/6 mice were randomly divided into 2 groups (n=6 each) using a random number table: C57BL/6 sham operation group (group C-S) and C57BL/6 I/R group (group C-I/R). The 12 CXCL16-KO mice were randomly divided into 2 groups (n=6 each) using a random number table: CXCL16-KO sham operation group (group KO-S) and CXCL16-KO I/R group (group KO-I/R). The right kidney was removed, and the left kidney was exposed, and the renal artery was then clamped for 45 min with atraumatic microclips followed by 24 h reperfusion to establish the model of renal I/R in anesthetized mice.Venous blood samples were taken at 24 h of reperfusion for determination of the serum blood urea nitrogen (BUN) and creatinine (Cr) concentrations.The renal specimens were obtained at 24 h of reperfusion for microscopic examination of the pathological changes, and the damage to the renal tubules was scored.The number of myeloperoxidase (MPO) positive cells (MPO+ cells), F4/80+ cells and CD3+ cells in renal tissues was counted by immunohistochemistry.The expression of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), IL-6, and macrophage inflammatory protein-2 (MIP-2) mRNA in renal tissues was determined by real-time reverse transcriptase polymerase chain reaction. Results Compared with group C-S, the serum BUN and Cr concentrations, renal tubular damage score, and the number of MPO+ , F4/80+ , and CD3+ cells were significantly increased, and the expression of TNF-α, IL-1β, IL-6 and MIP-2 mRNA was significantly up-regulated in group C-I/R (P<0.05). Compared with group KO-S, the serum BUN and Cr concentrations, renal tubular damage score, and the number of MPO+ , F4/80+ , and CD3+ cells were significantly increased, and the expression of TNF-α, IL-1β, IL-6 and MIP-2 mRNA was significantly up-regulated in group KO-I/R (P<0.05). Compared with group C-I/R, the serum BUN and Cr concentrations, renal tubular damage score, and the number of MPO+ , F4/80+ , and CD3+ cells were significantly decreased, and the expression of TNF-α, IL-1β, IL-6 and MIP-2 mRNA was significantly down-regulated in group KO-I/R (P<0.05). Conclusion CXCL16 is involved in the pathophysiological process of renal I/R injury in the mice. Key words: Chemokines, CXC; Kidney; Reperfusion injury

Effect of penehyclidine hydrochloride pretreatment on rhabdomyolysis-induced acute kidney injury in rats

Objective To evaluate the effect of penehyclidine hydrochloride pretreatment on rhabdomyolysis-induced acute kidney injury (AKI) in rats. Methods Forty-two pathogen-free male Sprague-Dawley rats, weighing 200-220 g, aged 2 months, were randomly divided into 3 groups using a random number table: control group (group C, n=6), AKI group (n=18), and penehyclidine hydrochloride group(group PH, n=18). The model of rhabdomyolysis-induced AKI was established by injecting 50% glycerol 10 ml/kg into the lateral muscle of bilateral hindlimbs in AKI and PH groups.The equal volume of normal saline was given in group C. Penehyclidine hydrochloride 0.2 mg/kg was injected intraperitoneally at 30 min before administration of glycerol in group PH.Six rats were selected at 1 h after administration of normal saline in group C, or at 1, 6 and 24 h after administration of glycerol, blood samples were collected from the inferior vena cava for determination of the serum blood urea nitrogen (BUN) and creatinine (Cr) concentrations by enzymic colorimetric method.The animals were sacrificed, and kidney specimens were obtained for pathologic examination and for determination of the expression of DJ-1 and phosphatase tensin homolog deleted on chromosome 10 (PTEN) encoding protein (by immuno-histochemistry and Western blot). The damage to the renal tubules was scored. Results Compared with group C, the serum BUN and Cr concentrations and renal tubular damage score were significantly increased, the expression of DJ-1 was down-regulated, and the expression of PTEN protein was up-regulated in group AKI (P<0.05 or 0.01). Compared with group AKI, the serum BUN and Cr concentrations and renal tubular damage score were significantly decreased, the expression of DJ-1 was up-regulated, and the expression of PTEN protein was down-regulated in group PH (P<0.05 or 0.01). Conclusion Penehyclidine hydrochloride pretreatment can reduce rhabdomyolysis-induced AKI probably by up-regulating the expression of DJ-1 and down-regulating the expression of PTEN protein in rats. Key words: Cholinergic antagonists; Rhabdomyolysis; Kidney failure, acute

Effect of hydrogen-rich saline on acute kidney injury after orthotopic liver transplantation and the role of autophagy

Objective To investigate the effects of hydrogen-rich saline on acute kidney injury after orthotopic liver transplantation(OLT)in rats and the role of autophagy. Methods Fifty-six healthy adult male Sprague-Dawley rats, weighing 220–250 g, served as donors and recipients.Thirty-two recipient rats were randomly assigned into 4 groups using a random number table: sham operation group(group S), OLT group, hydrogen-rich saline group(group HS), and autophagy inhibitor chloroquine group(group CQ). In group S, laparotomy was performed, and the related blood vessels were isolated.The model of OLT was established in OLT, HS and CQ groups.In OLT and HS groups, normal saline and hydrogen-rich saline 6 ml/kg were injected, respectively, through the inferior vena cava at 5 min before anhepatic phase.In group CQ, chloroquine 60 mg/kg was injected intraperitoneally at 1 h before establishment of the model, and the other treatments were similar to those previously described in group HS.Blood samples were obtained at 6 h of neohepatic phase for determination of serum blood urea nitrogen(BUN)and creatinine(Cr)concentrations.After the end of blood sampling, the left kidneys were removed for determination of malondialdehyde(MDA)content(using thiobarbituric acid method), superoxide dismutase(SOD)activity(xanthine oxidase method), and cell apoptosis(using TUNEL), and for examination of the pathological changes of renal tissues.The damage to the renal tubules was scored.Apoptosis index(AI)was calculated.The expression of phosphorylated p53(p-p53), activated caspase-3, cytochrome c(Cyt c), microtubule-associated protein light chain 3Ⅱ(LC3Ⅱ), and Beclin-1 was detected by Western blot analysis. Results Compared with group S, the levels of BUN, Cr, and MDA, AI, and renal tubular damage score were significantly increased, the SOD activity was decreased, and the expression of activated caspase-3, Cyt c and LC3Ⅱ was up-regulated(P 0.05). Compared with group OLT, the levels of BUN, Cr, and MDA, AI, and renal tubular damage score were significantly decreased, the SOD activity was increased, the expression of activated caspase-3, Cyt c was down-regulated, and the expression of LC3Ⅱ, Beclin-1 and p-p53 was up-regulated in group HS(P 0.05). Conclusion Hydrogen-rich saline can attenuate acute kidney injury after OLT, and the mechanism is associated with activation of p53, enhancement of autophagy and inhibition of cell apoptosis in rats. Key words: Hydrogen; Liver transplantation; Kidney injury; Autophagy; Apoptosis

Effect of adiponectin on renal fibrosis in mice subjected to renal ischemia-reperfusion

Objective To evaluate the effect of adiponectin on renal fibrosis in mice subjected to renal ischemia-reperfusion (I/R). Methods Forty-eight male C57BL/6 mice, aged 8 weeks, weighing 20–25 g, were randomly divided into 4 groups (n =12 each) using a random number table: control group (group C), adiponectin group (group APN) and group I/R.Renal ischemia was induced by occlusion of the left renal pedicles for 30 min with atraumatic microclips followed by reperfusion.Globular domain of adiponectin 5 μg/g was injected intraperitoneally at 15 min before ischemia and every 24 h during reperfusion for 2 consecutive weeks in group I/R+ APN.In group C, the left renal pedicles were only isolated, but not occluded, and the equal volume of normal saline was given at the corresponding time point in groups C and I/R.In group APN, the left renal pedicles were only isolated, but not occluded, and the medication was similar to those previously described in group I/R+ APN.At 48 h of reperfusion, 6 mice were sacrificed in each group, the left kidneys were removed for detection of cell apoptosis (using TUNEL), and the damage to the renal tubules was scored.Apoptosis index (AI) was calculated.The left 6 mice in each group were sacrificed at 2 weeks of reperfusion, and the left kidneys were obtained, the degree of fibrosis was evaluated using Sirus red staining, and the expression of typeⅠcollagen (Col-Ⅰ), a-smooth muscle actin (α-SMA), and fibronectin (FN) was detected by Western blot. Results Compared with group C, the renal tubular damage score, AI and degree of fibrosis were significantly increased, and the expression of COL-Ⅰ, α-SMA and FN was up-regulated in I/R and APN+ I/R groups (P 0.05). Compared with group I/R, the renal tubular damage score, AI and degree of fibrosis were significantly decreased, and the expression of COL-Ⅰ, α-SMA and FN was down-regulated in group APN+ I/R (P<0.05). Conclusion Adiponectin can alleviate renal fibrosis in mice subjected to renal I/R. Key words: Adiponectin; Kidney; Reperfusion injury; Fibrosis

Protection against renal ischaemia/reperfusion injury: A comparative experimental study of the effect of ischaemic preconditioning vs. postconditioning

ObjectiveTo compare the effect of ischaemic preconditioning (Ipre) vs. ischaemic postconditioning (Ipost) on renal ischaemia/reperfusion (I/R) injury in rats. Materials and methodsIn all, 120 male Sprague–Dawley rats were classified into four groups of 30 rats each, designated sham, control, Ipre and Ipost. Renal function, including serum creatinine, blood urea nitrogen (BUN), creatinine clearance (CrCl), fractional Na excretion (FENa) and renal histopathology were measured at 2, 24 and 48h after ischaemia. Markers of lipid peroxidation (malondialdehyde, MDA), superoxide dismutase (SOD) and reduced glutathione (GSH) were measured in kidney tissues during the same intervals. ResultsIpre caused a significant improvement in renal function, as indicated by a significant decrease in serum creatinine, BUN and FENa, with a significant increase in CrCl. However, Ipost caused no significant improvement in renal function. Morphologically Ipre caused a marked significant improvement in the renal tubular damage score compared to Ipost. Also, Ipre caused a significant decrease in MDA, and significant increase in GSH and SOD when compared to Ipost. ConclusionIpre is more potent than Ipost for improving the renal injury induced by I/R. Ipre caused a marked improvement in renal function and morphology, while Ipost caused a minimal improvement in morphology only. Moreover, Ipre caused a marked and significant reduction in oxidative stress in kidney tissues, while Ipost caused a minimal reduction.

Fasudil Ameliorates Rhabdomyolysis-Induced Acute Kidney Injury via Inhibition of Apoptosis

During times of war or natural disasters, rhabdomyolysis leading to acute kidney injury (AKI) can assume epidemic proportions. Fasudil attenuates ischemia/reperfusion-induced AKI. We investigated the therapeutic effect of an early application of fasudil on AKI induced by rhabdomyolysis and explored the potential mechanisms. Male Wistar rats were randomly divided into a control group (saline, 7 mL/kg, i.m.), a Gly group (50% glycerol, 7 mL/kg, i.m.), and a fasudil group (50% glycerol, 7 mL/kg, i.m.; fasudil, 20 mg/kg bodyweight, i.p., three times every 24 h beginning 72 h before glycerol administration). Serum creatinine, blood urea nitrogen (BUN), and histopathological changes were used to demonstrate kidney function 24 h after the glycerol injection. Cell apoptosis and the expression of rho-associated protein kinase member (ROCK1), phosphatase and tensin homolog (PTEN), P-Akt, and caspase-8, -9, and -3 were measured. Serum creatinine and BUN levels increased significantly in Gly group compared with control group. Both levels decreased after fasudil treatment. The renal tubular damage score was significantly lower and cell apoptosis was significantly less in fasudil group compared with Gly group. The expression levels of ROCK1, PTEN, and caspase-8, -9, and -3 were upregulated significantly in Gly group, and their expression was reduced in the fasudil group. The P-Akt level was decreased in Gly group and upregulated significantly in fasudil group. Early application of fasudil reduced rhabdomyolysis-associated renal injury by inhibiting Rho kinase and thereby activating the PI-3K/Akt pathway, which decreased cell apoptosis via both the intrinsic and extrinsic apoptotic pathways.