Renal ischemia-reperfusion injury (IRI) is a major contributor to acute kidney injury (AKI), leading to substantial morbidity and mortality. Spexin (SPX), a 14-amino acid endogenous peptide involved in metabolic regulation and immune modulation, has not yet been studied in the context of chronic treatment and renal IRI. This study evaluated the effects of exogenous SPX on renal function, histopathological changes, and molecular pathways in both IRI-induced injured and healthy kidneys. Twenty-eight male BALB/c mice were divided into four groups: control, SPX, IRI, and SPX+IRI. IRI was induced by 30 minutes of bilateral renal ischemia followed by 6 hours of reperfusion. Renal injury markers, histopathological changes, inflammatory mediators, apoptotic markers, and fibrosis-related proteins were analyzed. SPX significantly exacerbated IRI-induced kidney injury by activating the Wnt/β-catenin signaling pathway and promoting the upregulation of pro-inflammatory, pro-apoptotic, and pro-fibrotic mediators. It is noteworthy that SPX exerted more severe deleterious nephrotoxic effects in the healthy kidney compared to those observed in the IRI-induced injured kidney. These findings indicate that chronic treatment with SPX administration may have intrinsic pro-inflammatory, pro-apoptotic and fibrotic properties, raising concerns about its therapeutic potential. Further research is needed to clarify its physiological role and therapeutic implications in kidney diseases.
Animals ; Reperfusion Injury/chemically induced* ; Male ; Mice, Inbred BALB C ; Mice ; Acute Kidney Injury/metabolism* ; Kidney/blood supply* ; Peptide Hormones/adverse effects* ; Apoptosis/drug effects* ; Wnt Signaling Pathway/drug effects* ; Disease Models, Animal

Acute kidney injury (AKI) is an important factor for the occurrence and development of CKD. The protective effect of dihydroartemisinin on AKI and and reported mechanism have not been reported. In this study, we used two animal models including ischemia-reperfusion and UUO, as well as a high-glucose-stimulated HK-2 cell model, to evaluate the protective effect of dihydroartemisinin on premature senescence of renal tubular epithelial cells in vitro and in vivo. We demonstrated that dihydroartemisinin improved renal aging and renal injury by activating autophagy. In addition, we found that co-treatment with chloroquine, an autophagy inhibitor, abolished the anti-renal aging effect of dihydroartemisinin in vitro. These findings suggested that activation of autophagy/elimination of senescent cell might be a useful strategy to prevent AKI/UUO induced renal tubular senescence and fibrosis.
Animals ; Kidney ; Acute Kidney Injury/chemically induced* ; Ischemia ; Reperfusion Injury/drug therapy* ; Autophagy ; Reperfusion

To investigate the effects of triptolide on inflammation and apoptosis induced by focal cerebral ischemia/reperfusion in rats.The rat model of focal cerebral ischemia/reperfusion injury was established according to Longa's method. A total of 80 SD rats were randomly divided into 5 groups:normal control, sham group, DMSO group, middle cerebral artery occlusion (MCAO) group, and MCAO with tripolide treatment group. TTC staining was used to examine the site and volume of cerebral infarction, and Longa score was employed for neurological disorders measurement. Number of astrocytes was measured by fluorescence staining, and neuronal apoptosis was determined by TUNEL staining. The expressions of inducible nitric oxide synthase(iNOS), cyclooxygenase 2(COX-2) and NF-κB proteins were detected by immunohistochemistry, and the expression of iNOS, COX-2 mRNA was detected by real-time PCR.Compared with DMSO group and MCAO group, brain edema was improved (80.03±0.46)% (<0.05), infarct volume was reduced (8.3±1.4)% (<0.01), Longa score was decreased (1.38±0.20,<0.05) in triptolide treatment group. Meanwhile triptolide also dramatically reduced the number of GFAP-positive astrocytes (<0.05), alleviated protein expression of COX-2 (91.67±1.31), iNOS (95.24±5.07) and NF-κB (75.03±2.06) triggered by MCAO (all<0.05), and induced a down-regulation of cell apoptosis as showed by TUNEL assay (64.15±3.52,<0.05).Triptolide can reduce the cerebral infarction volume, attenuate brain edema and ameliorate the neurological deficits induced by cerebral ischemia-reperfusion injury rats, indicating that it might be used as a potential anti-inflammatory agent.
Animals ; Apoptosis ; drug effects ; Astrocytes ; Brain Edema ; drug therapy ; Brain Injuries ; chemically induced ; drug therapy ; Brain Ischemia ; chemically induced ; Cyclooxygenase 2 ; drug effects ; Diterpenes ; pharmacology ; Down-Regulation ; drug effects ; Epoxy Compounds ; pharmacology ; Infarction, Middle Cerebral Artery ; chemically induced ; drug therapy ; Inflammation ; drug therapy ; Male ; NF-kappa B ; drug effects ; Nitric Oxide Synthase Type II ; drug effects ; Phenanthrenes ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; chemically induced ; drug therapy

OBJECTIVETo investigate the Effect of 2,3-butanedione monoxime (BDM) on calcium paradox-induced heart injury and its underlying mechanisms.

METHODSThirty-two adult male SD rats were randomized into 4 groups, namely the control group, BDM treatment control group, calcium paradox group, and BDM treatment group. Isolated Sprague Dawley male rat hearts underwent Langendorff perfusion and the left ventricular pressure (LVP) and left ventricular end-diastolic pressure (LVEDP) were monitored. Left ventricular developed pressure (LVDP) was calculated to evaluate the myocardial performance. Lactate dehydrogenase (LDH) content in the coronary flow was determined. Triphenyltetrazolium chloride staining was used to measure the infarct size, and myocardial cell apoptosis was tested with TUNEL method. Western blotting was used to determine the expression of cleaved caspase-3 and cytochrome c.

RESULTSCompared with the control group, BDM at 20 mmol/L had no effect on cardiac performance, cell death, apoptotic index or the content of LDH, cleaved caspase-3 and cytochrome c at the end of perfusion under control conditions (P>0.05). Calcium paradox treatment significantly decreased the cardiac function and the level of LVDP and induced a larger infarct size (P<0.01), an increased myocardial apoptosis index (P<0.01), and up-regulated expressions of cleaved caspase-3 and cytochrome c (P<0.01). BDM (20 mmol/L) significantly attenuated these effects induced by calcium paradox, and markedly down-regulated the levels of LVEDP and LDH (P<0.01), lowered myocardial apoptosis index, decreased the content of cleaved caspase-3 and cytochrome c (P<0.01), increased LVDP, and reduced the infarct size (P<0.01).

CONCLUSIONBDM suppresses cell apoptosis and contracture and improves heart function and cell survival in rat hearts exposed to calcium paradox, suggesting the value of BDM as an potential drug for myocardial ischemia reperfusion injur.

Animals ; Apoptosis ; Calcium ; adverse effects ; Caspase 3 ; metabolism ; Cytochromes c ; metabolism ; Diacetyl ; analogs & derivatives ; pharmacology ; Heart ; drug effects ; physiopathology ; In Vitro Techniques ; L-Lactate Dehydrogenase ; metabolism ; Male ; Myocardial Reperfusion Injury ; chemically induced ; drug therapy ; Rats ; Rats, Sprague-Dawley ; Ventricular Function, Left

To study the antiarrhythmic effect of the newly developed alpha/beta-blocker TJ0711, a variety of animal models of arrhythmia were induced by CaCl2, ouabain and ischemia/reperfusion. Glass microelectrode technique was used to observe action potentials of right ventricular papillary muscle of guinea pig. The onset time of arrhythmia induced by CaCl2 was significantly prolonged by TJ0711 at 0.75, 1.5 and 3 mg x kg(-1) doses. TJ0711 (1.5 and 3 mg x kg(-1)) can significantly shorten the ventricular tachycardia (VT) and ventricular fibrillation (VF) duration, the incidence of VF and mortality were significantly reduced. On ischemia-reperfusion-induced arrhythmic model, TJ0711 (0.25, 0.5, 1 and 2 mg x kg(-1)) can significantly reduce the ventricular premature contraction (PVC), VT, VF incidence, mortality, arrhythmia score with a dose-dependent manner. At the same time, rats serum lactate dehydrogenase (LDH) and creatine kinase (CK) activities decreased significantly by TJ0711 (1 and 2 mg x kg(-1)). Ouabain could cause arrhythmia in guinea pigs, when TJ0711 (0.375, 0.75, 1.5 and 3 mg x kg(-1)) was given, the doses of ouabain inducing a variety of arrhythmia PVC, VT, VF, cardiac arrest (CA) were significantly increased with a dose-dependent manner. In the TJ0711 0.1-30 micromol x L(-1) concentration range, guinea pig right ventricular papillary muscle action potential RP (rest potential), APA (action potential amplitude) and V(max) (maximum velocity of depolarization) were not significantly affected. APD20, APD50 and APD90 had a shortening trend but no statistical difference with the increase of TJ0711 concentration. TJ0711 has antiarrhythmic effect on the sympathetic nerve excitement and myocardial cell high calcium animal arrhythmia model. Myocardial action potential zero phase conduction velocity and resting membrane potential were not inhibited by TJ0711. APD20, APD50 and APD90 were shortened by TJ0711 at high concentration. Its antiarrhythmic action mechanism may be besides the action of blocking beta1 receptor, may also have a strong selective blocking action on alpha1 receptor and reducing intracellular calcium concentration.
Action Potentials ; drug effects ; Adrenergic alpha-Antagonists ; administration & dosage ; pharmacology ; Adrenergic beta-Antagonists ; administration & dosage ; pharmacology ; Animals ; Anti-Arrhythmia Agents ; administration & dosage ; pharmacology ; Arrhythmias, Cardiac ; blood ; chemically induced ; etiology ; pathology ; physiopathology ; Calcium Chloride ; Creatine Kinase ; blood ; Dose-Response Relationship, Drug ; Female ; Guinea Pigs ; Heart Ventricles ; cytology ; Lactate Dehydrogenases ; blood ; Male ; Myocardial Reperfusion Injury ; complications ; Myocytes, Cardiac ; drug effects ; physiology ; Ouabain ; Papillary Muscles ; cytology ; Phenoxypropanolamines ; administration & dosage ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the protective effect of low-dose ketamine against intestinal ischemia reperfusion injury following pneumoperitoneum with carbon dioxide in rats.

METHODSThirty healthy male adult SD rats (body weight 280-320 g) were randomized into sham-operated group, model group and ketamine group and subjected to pneumoperitoneum for 120 min with carbon dioxide (not in sham-operated group). The rats in ketamine group received an intraperitoneal injection of 10 mg/kg ketamine 10 min before pneumoperitoneum, and those in the other two groups received saline injection. Fifteen minutes after pneumoperitoneum or sham operation, the small intestines were sampled to detect the content of malondialdehyde (MDA) and fore pathological testing. ELISA was used to detect the serum levels of I-FABP, TNF-α IL-6 and IL-8.

RESULTSPneumoperitoneum caused a significant increase in intestinal MDA content (P<0.05), which was lowered by ketamine pretreatment (P<0.05). Serum I-FABP, TNF-α, IL-6 and IL-8 levels all significantly increased following pneumoperitoneum (P<0.05) and were obviously lowered by ketamine pretreatment (P<0.05). Pneumoperitoneum also caused obvious pathologies in intestinal mucosa, which were ameliorated by ketamine pretreatment.

CONCLUSIONLow-dose ketamine preconditioning can reduce the inflammatory reaction and lessen oxidative damage in the intestinal mucosa following pneumoperitoneum in rats.

Animals ; Carbon Dioxide ; Dose-Response Relationship, Drug ; Fatty Acid-Binding Proteins ; blood ; Interleukin-6 ; blood ; Interleukin-8 ; blood ; Intestine, Small ; blood supply ; metabolism ; pathology ; Ketamine ; administration & dosage ; therapeutic use ; Male ; Malondialdehyde ; metabolism ; Pneumoperitoneum ; chemically induced ; complications ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; blood ; etiology ; metabolism ; pathology ; prevention & control ; Tumor Necrosis Factor-alpha ; blood

BACKGROUND/AIMS: Ischemic preconditioning (IP) decreases severity of liver necrosis and has anti-apoptotic effects in previous studies using liver regeneration in normal rats. This study assessed the effect of IP on liver regeneration after hepatic resection in cirrhotic rats. METHODS: To induce liver cirrhosis, thioacetamide (300 mg/kg) was injected intraperitoneally into Sprague-Dawley rats twice per week for 16 weeks. Animals were divided into four groups: non-clamping (NC), total clamping (TC), IP, and intermittent clamping (IC). Ischemic injury was induced by clamping the left portal pedicle including the portal vein and hepatic artery. Liver enzymes alanine transaminase (ALT) and aspartate aminotransferase (AST) were measured to assess liver damage. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining for apoptosis and proliferating cell nuclear antigen (PCNA) staining for cell replication were also performed. RESULTS: Day-1 ALT and AST were highest in IP, however, levels in NC and IC were comparably low on days 1-7. There was no significant correlation of AST or ALT with experimental groups (P=0.615 and P=0.186). On TUNEL, numbers of apoptotic cells at 100x magnification (cells/field) were 31.8+/-24.2 in NC, 69.0+/-72.3 in TC, 80.2+/-63.1 in IP, and 21.2+/-20.8 in IC (P<0.05). When regeneration capacity was assessed by PCNA staining, PCNA-positive cells (cells/field) at 400x were 3.4+/-6.0 in NC, 16.9+/-69 in TC, 17.0+/-7.8 in IP and 7.4+/-7.6 in IC (P<0.05). CONCLUSIONS: Although regeneration capacity in IP is higher than IC, the liver is vulnerable to ischemic damage in cirrhotic rats. Careful consideration is needed in applying IP in the clinical setting.
Alanine Transaminase/blood ; Animals ; Apoptosis ; Aspartate Aminotransferases/blood ; Constriction ; Hepatectomy/methods ; Hepatic Artery ; *Ischemic Preconditioning ; Liver/blood supply ; Liver Cirrhosis, Experimental/chemically induced/complications/*pathology ; *Liver Regeneration ; Proliferating Cell Nuclear Antigen/metabolism ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury/complications/enzymology/pathology ; Thioacetamide/toxicity

BACKGROUNDTreatment with inhaled carbon monoxide (CO) has been shown to ameliorate intestinal injury in experimental animals induced by lipopolysaccharide (LPS) or ischemia-reperfusion. We hypothesized that CO intraperitoneal administration (i.p.) might provide similar protection to inhaled gas. This study aimed to investigate the effects of continuous 2 L/min of 250 ppm CO i.p. on rat intestine injury induced by LPS and to try to develop a more practical means of delivering the gas.

METHODSA total of 72 male Sprague-Dawley rats were randomly assigned to 4 groups: control group, CO i.p. group, LPS group and LPS+CO i.p. group. One hour after intravenously received 5 mg/kg LPS, the rats in LPS group and LPS+CO i.p. group were exposed to room air and 2 L/min of 250 ppm CO i.p., respectively, and the rats of control group and CO i.p. group intravenously received an equal volume of 0.9% NaCl and 1 hour later, were exposed to room air and 2 L/min of 250 ppm CO i.p., respectively. One, 3 and 6 hour of each group after treated with room air or CO i.p., the animals (n = 6 for each time point) were sacrificed and intestinal tissues were collected for determinating the levels of platelet activator factor (PAF) and intercellular adhesion molecule-1 (ICAM-1) with enzyme-lined immunosorbent assays. The maleic dialdehyde (MDA) content and the myeloperoxidase (MPO) activity were determined with a chemical method. The phosphorylated p38 mitogen activated protein kinase (MAPK) expression was assayed with Western blotting and the cell apoptotic rate with flow cytometery. The arterial oxygenation was measured by blood gas analysis, and the pathology determined by light microscope.

RESULTSAfter treatment with 2 L/min of 250 ppm CO i.p., the increase of PAF, ICAM-1, MDA, MPO, and cell apoptotic rate induced by LPS was markedly reduced (P < 0.05 or 0.01), and accompanied by ameliorating intestine injury. Western blotting showed that these effects of CO i.p. were mediated by p38 MAPK pathway. There were no significant differences in all observed parameters between control group and CO i.p. group.

CONCLUSIONThe injury to the intestine via anti-oxidant, anti-inflammation and anti-apoptosis, which may involve the p38 MAPK pathway, was induced by 2 L/min of 250 ppm CO i.p. exerting potent protection against LPS.

Aldehydes ; metabolism ; Animals ; Blotting, Western ; Carbon Monoxide ; administration & dosage ; pharmacology ; therapeutic use ; Flow Cytometry ; Intercellular Adhesion Molecule-1 ; metabolism ; Intestines ; drug effects ; metabolism ; pathology ; Lipopolysaccharides ; toxicity ; Male ; Microscopy ; Peroxidase ; metabolism ; Platelet Activating Factor ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; chemically induced ; drug therapy ; p38 Mitogen-Activated Protein Kinases ; metabolism

The myocardial protective effects of endothelin antagonist in ischemic cardiomyopathy (ICMP), doxorubicin-induced cardiomyopathy (DOX) and pressure-overload hypertrophy by transverse aortic constriction (TAC) models have been predicted to be different. The objective of this experiment, therefore, is to evaluate the myocardial protective effect of tezosentan, an endothelin receptor antagonist, in various experimental heart failure models. Sprague-Dawley rats (6-8 weeks old, 200-300 g) were randomized to three experimental groups (n=30 each): ICMP; DOX; and TAC group. Each of these groups was randomly assigned further to the following subgroups (n=10 each): sham-operated ischemia-reperfusion subgroup (SHAM); tezosentan treated ischemia-reperfusion subgroup (Tezo); and tezosentan non-treated ischemia-reperfusion subgroup (N-Tezo). Total circulatory arrest was induced for 1 hr, followed by 2 hr of reperfusion. The left ventricular developed pressure, peak positive and negative first derivatives, and coronary blood flow were significantly different (P<0.05) among the SHAM, Tezo, and N-Tezo subgroups of the ICMP group at 30 min of reperfusion, but there were no statistically significant differences among the subgroups of the DOX and TAC groups. In conclusion, tezosentan, an endothelin receptor antagonist, showed myocardial protection effects only on the ischemic cardiomyopathy rat model, but not in the non-ischemic heart failure rat models.
Animals ; Cardiomyopathies/chemically induced/drug therapy/physiopathology ; Coronary Vessels/physiology ; Disease Models, Animal ; Doxorubicin/toxicity ; Heart Failure/*drug therapy/physiopathology ; Hypertrophy/drug therapy/physiopathology ; Male ; Pressure ; Pyridines/*therapeutic use ; Rats ; Rats, Sprague-Dawley ; Receptors, Endothelin/*antagonists & inhibitors/metabolism ; Reperfusion Injury/*drug therapy/physiopathology/surgery ; Tetrazoles/*therapeutic use ; Vasodilator Agents/*therapeutic use ; Ventricular Function, Left/physiology

OBJECTIVE: To investigate the effect of acute cardiac injury on the activation of interleukin-1 beta (IL-1 beta) signaling in the spinal cord. METHODS: Acute cardiac injury rat model was established by intra-myocardial injection of formalin through diaphragm. IL-1 beta expression was determined by Western blot, immunohistochemistry and in situ hybridization. The DNA binding activities of 2 IL-1 beta transcription factors, activator protein (AP)-1 and nuclear factor kB (NF-kappaB) were measured by electrophoretic mobility shift assay (EMSA). RESULTS: After cardiac injury, the IL-1 beta protein level was dramatically upregulated in the spinal cord. The upregulated IL-1 beta was mainly expressed in the neurons in the lamina II approximately IV of the spinal cord. In response to cardiac injury, the DNA binding activities of NF-kappaB and AP-1 were greatly activated. CONCLUSION Acute cardiac injury could activate the spinal IL-1 beta signaling, which, in turn, may be involved in the progression of heart failure after injury.
Animals ; Interleukin-1beta ; genetics ; metabolism ; Male ; Myocardial Reperfusion Injury ; chemically induced ; metabolism ; pathology ; Myocardium ; metabolism ; pathology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Signal Transduction ; Spinal Cord ; metabolism