Hepatic Ischemia-reperfusion Injury In Rats Research Articles

Inhibitory role of remifentanil in hepatic ischemia-reperfusion injury through activation of Fmol/Parkin signaling pathway: A study based on network pharmacology analysis and high-throughput sequencing

BackgroundThis study was conducted to elucidate the critical molecular pathways underlying the protective effects of remifentanil against hepatic ischemia-reperfusion injury in rats. Our approach integrated network pharmacology analysis with high-throughput sequencing to achieve a comprehensive understanding of the mechanisms involved. Study Design/MethodsThe study utilized GSE24430 gene expression data from GEO to investigate remifentanil's impact on Hepatic Ischemia-Reperfusion Injury in rats. Weighted Correlation Network Analysis (WGCNA) was employed to pinpoint crucial genes and identify modules of co-expressed genes. Differential analysis with the "Limma" package revealed genes differentially expressed in IRI vs. control groups. PubChem and PharmMapper provided target genes affected by remifentanil. Protein-protein interaction networks were constructed via GeneCards and STRING. Functional analysis pinpointed core genes involved in remifentanil's IRI alleviation. IRI rat models were established, and hepatic injury indicators, liver structure via H&E staining, autophagosome counts via electron microscopy, and gene/protein expression via RT-qPCR and Western blot were assessed. High-throughput sequencing analyzed molecular pathways affected by varying remifentanil doses in IRI rats. ResultsIn the study, we discovered four primary co-expression modules associated with hepatic IRI, and the grey module exhibited the highest correlation with hepatic IRI.A total of sixty-eight genes that were differentially expressed were found to have a connection with hepatic IRI.Network pharmacology analysis found that remifentanil may alleviate hepatic IRI through Fmol.found that the Fmol/Parkin signaling pathway may alleviate hepatic IRI via Additionally, the database autophagy. The established hepatic IRI rat models further confirmed the above findings. ConclusionOur study established that remifentanil triggers the Fmol/Parkin signaling cascade, amplifying the expression levels of Fmol and Parkin. This process culminates in the activation of autophagy within hepatic cells, ultimately alleviating hepatic ischemia-reperfusion injury (IRI).

Zafirlukast protects against hepatic ischemia-reperfusion injury in rats via modulating Bcl-2/Bax and NF-κB/SMAD-4 pathways.

Hepatic ischemia/reperfusion injury (IRI) is a clinical problem commonly during liver transplantation and other liver surgery. This study aimed to evaluate the protective effect of zafirlukast (ZFK) on IR-induced hepatic injury and investigate its relevant protective mechanism. Thirty-two male Wistar albino rats were randomly allocated to four groups: sham, IRI, ZFK, and ZFK+IR groups. ZFK was administered orally in a dose of 80mg/kg/day for 10 consecutive days. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBL) levels, and gamma glutamyl transferase (GGT) activity were estimated. Liver tissues were used to assess oxidative stress biomarkers including malondialdehyde (MDA), myeloperoxidase (MPO), nitric oxide (NOx), and reduced glutathione (GSH) contents. Inflammatory cytokines, tumor necrosis factor alpha (TNF-α) and interleukin-33 (IL-33), in addition to apoptosis biomarkers, BCL2 associatedXprotein (Bax), B-cell lymphoma 2 (Bcl2) and galactine-9 (GAL9) proteins were also assessed. Western blot analysis was performed for vascular endothelial growth factor (VEGF) and fibrinogen expressions. Immunohistochemical analysis for hepatic nuclear factor-kappa B (NF-κB) and SMAD-4 was done in addition to histopathological examination. Our study revealed that ZFK pre-treatment resulted in liver function restoration and oxidative stress correction. Moreover, inflammatory cytokines were significantly reduced and a remarkable reduction of apoptosis, angiogenesis, and clotting formation has been indicated. Additionally, a significant reduction in SMAD-4 and NF-kB protein expressions was observed. These results were supported by hepatic architecture improvement. Our findings revealed that ZFK possesses a potential protective effect against liver IR possibly through its antioxidant, anti-inflammatory and anti-apoptotic properties.

Adipose delivered stem cells protect liver after ischemia-reperfusion injury by controlling autophagy

Objective: Ischemia-reperfusion(I/R) injury is an unavoidable side effect of liver surgery and transplantation. A potentially useful tool for cellular therapy and tissue engineering is adipose-derived stem cells (ADSCs).The process of autophagy is used by the cell to break down inappropriate molecules.The study's goal was to examine the impact of ADSCs on the autophagic pathway after rat hepatic ischemia-reperfusion injury. Material and Methods: Thirty male rats used in our study were divided into control, ADSC, ischemia, I/R, and I/R+ ADSC groups (n = 6). Liver tissues were stained with hematoxylin-eosin and histological changes were evaluated with Suzuki scoring. Immunoexpressions of transforming growth factor (TGF-β) and autophagy markers LC3B, p62 were analyzed using the immunohistochemical method. Results: As a result of histological evaluation the ischemia and I/R groups displayed sinusoid congestion, vacuolization, and necrosis in liver tissues. We showed that the immunostaining of LC3B and TGF- β were elevated, and p62 decreased in the rat liver from ischemia and I/R groups when compared to the control group. Conclusion: ADSCs reduced the excessive level of autophagy and structural damage to hepatocytes and the pathological alterations in the liver after ıschemia-reperfusion injury.

Is aryl hydrocarbon receptor antagonism after ischemia effective in alleviating acute hepatic ischemia-reperfusion injury in rats?

Aryl hydrocarbon receptors (AhRs) have been reported to be important mediators of ischemic injury in the brain. Furthermore, the pharmacological inhibition of AhR activation after ischemia has been shown to attenuate cerebral ischemia-reperfusion (IR) injury. Here, we investigated whether AhR antagonist administration after ischemia was also effective in ameliorating hepatic IR injury. A 70% partial hepatic IR (45-min ischemia and 24-h reperfusion) injury was induced in rats. We administered 6,2′,4′-trimethoxyflavone (TMF, 5 mg/kg) intraperitoneally 10 min after ischemia. Hepatic IR injury was observed using serum, magnetic resonance imaging-based liver function indices, and liver samples. TMF-treated rats showed significantly lower relative enhancement (RE) values and serum alanine aminotransferase (ALT) and aspartate aminotransferase levels than did untreated rats at 3 h after reperfusion. After 24 h of reperfusion, TMF-treated rats had significantly lower RE values, ΔT1 values, serum ALT levels, and necrotic area percentage than did untreated rats. The expression of the apoptosis-related proteins, Bax and cleaved caspase-3, was significantly lower in TMF-treated rats than in untreated rats. This study demonstrated that inhibition of AhR activation after ischemia was effective in ameliorating IR-induced liver injury in rats.

Protective effect of the combined use of L-carnitine and L-arginine against hepatic ischemia-reperfusion injury in rats

Protective effect of the combined use of L-carnitine and L-arginine against hepatic ischemia-reperfusion injury in rats

Fluorescein clearance kinetics in blood and bile indicates hepatic ischemia-reperfusion injury in rats

Quantitative measurement of the degree of hepatic ischemia-reperfusion injury (IRI) is crucial for developing therapeutic strategies for its treatment. We hypothesized that clearance of fluorescent dye through bile metabolism may reflect the degree of hepatic IRI. In this study, we investigated sodium fluorescein clearance kinetics in blood and bile for quantifying the degree of hepatic IRI. Warm ischemia times (WITs) of 0, 30, or 60 min followed by 1 h or 4 h of reperfusion, were applied to the median and lateral lobes of the liver in Sprague-Dawley rats. Subsequently, 2 mg/kg of sodium fluorescein was injected intravenously, and blood and bile samples were collected over 60 min to measure fluorescence intensities. The bile-to-plasma fluorescence ratios demonstrated an inverse correlation with WIT and were distinctly lower in the 60-min WIT group than in the control or 30-min WIT groups. Bile-to-plasma fluorescence ratios displayed superior discriminability for short versus long WITs when measured 1 h after reperfusion versus 4 h. We conclude that the bile-to-blood ratio of fluorescence after sodium fluorescein injection has the potential to enable the quantification of hepatic IRI severity.NEW & NOTEWORTHY Previous attempts to use fluorophore clearance to test liver function have relied on a single source of data. However, the kinetics of substrate processing via bile metabolism include decreasing levels in blood and increasing levels in bile. Thus, we analyzed data from blood and bile to better reflect fluorescein clearance kinetics.

Could Ambroxol reduce cytokines in hepatic ischemia-reperfusion injury in rats?

The aim of the study is to examine the effect of Ambroxol on TNF-α and IL-1β released after liver ischemia-reperfusion injury. Many drugs are being tried to reduce ischemia-reperfusion injury, which is life threating problem after many liver surgeries. In this study, it was investigated whether Ambroxol reduces the release of pro-inflammatory cytokines released after liver ischemia-reperfusion injury. Twenty-four Wistar albino rats were divided into 3 groups as Control (CTR; n=8), hepatic ischemia reperfusion (H-IR; n=8) and hepatic ischemia reperfusion+Ambroxol (H-IR+AMB; n=8). In H-IR+AMB group, Ambroxol (30 mg/kg) was administered orally 30 minutes before ischemia period. In H-IR and H-IR+AMB groups underwent 45 minutes of hepatic ischemia followed by a 60-minute reperfusion period. After reperfusion period, tissue and blood samples were collected from euthanised animals. ALT, AST, ALP, LDH, TNF-α, IL-1β concentrations and liver tissues were evaluated. Serum ALT, ALP, AST, LDH, TNF-α and IL-1β values were lower in the H-IR+AMB group compared to the H-IR group. In the histopathological examination, hepatocyte degeneration and congestion in the H-IR group were higher than in the H-IR+AMB group. It was determined that Ambroxol treatment suppressed the production of pro-inflammatory cytokines TNF-α and IL-1β in rats undergoing hepatic ischemia reperfusion (Tab. 1, Fig. 2, Ref. 28).

Effects of L-Theanine on Hepatic Ischemia-Reperfusion Injury in Rats.

The effects of L-theanine on hepatic microcirculation during hepatic ischemia-reperfusion injury have not yet been investigated. The aim of this study was to investigate the influence of L-theanine on hepatic ischemia-reperfusion injury in rats. Thirty-two male Sprague Dawley rats weighing 250 to 300 g were used. Rats were divided into 4 groups: sham + saline, sham + L-theanine, hepatic ischemia-reperfusion injury + saline, and hepatic ischemia-reperfusion injury + L-theanine. Hepatic ischemia-reperfusion injury in rats was induced by 60 minutes of 70% ischemia and 4 hours of reperfusion. The extent of hepatic cell injury, functional capillary density, hepatic functions, and changes in some enzyme markers in hepatic tissue were investigated in the 4 groups. The induction of hepatic ischemia-reperfusion injury resulted in significant increases in hepatic necrosis; serum activity of alanine aminotransferase, lactate dehydrogenase, gamma-glutamyltransferase, and tumor necrosis factor alpha; tissue activity of inducible nitric oxide synthase, myeloperoxidase, and malondialdehyde, and oxide glutathione; and H score for hypoxia-inducible factor 1-alpha in the liver. In the liver, there were significant reductions in reduced glutathione, ratio of reduced glutathione-to-oxide glutathione, and functional capillary density. The use of L-theanine improved these changes. L-theanine demonstrated protective effects on hepatic injury after ischemia-reperfusion injury in rats. However, new studies are needed to confirm the preventive or reducing effects of L-theanine on hepatic ischemia-reperfusion injury.

Retraction for Wei et al. Electroacupuncture stimulation at Yanglingquan acupoint ameliorates hepatic ischemia-reperfusion injury by down-regulating ET-1 to inhibit TAK1-JNK/p38 pathway.

The current study set out to investigate the molecular mechanism of electroacupuncture (EA) stimulation at Yanglingquan acupoint (GB34) in hepatic ischemia-reperfusion injury (HIRI) in rats via regulation of the endothelin-1 (ET-1) mediated transforming growth factor-β-activated kinase-1 (TAK1)-c-Jun NH2-terminal kinase (JNK)/p38 signaling pathway. First, EA stimulation was applied to the constructed rat model of HIRI at GB34. Subsequently, the activities of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and myeloperoxidase (MPO) in liver tissues were measured. Apoptotic changes in liver tissues in rats with HIRI were observed using TUNEL staining. Western blot assay was employed to determine the expression patterns of Bcl-2, Bax, c-caspase-3 and the activation of TAK1-JNK/p38 signaling pathway, and immunohistochemistry was conducted to determine the protein expression patterns of c-caspase-3 and ET-1. In addition, ELISA was performed to determine the levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 in serum. The results demonstrated a significant decline in the activities of AST and ALT and hepatocyte apoptosis in rats with HIRI following EA stimulation. Meanwhile, EA stimulation brought about decreases in the expression levels of Bcl-2, Bax and c-caspase-3, MPO activity, TNF-α, IL-1β and IL-6 in serum, and diminished those of ET-1 in liver tissues, in addition to inhibiting the TAK1-JNK/p38 signaling pathway. Over-expression of ET-1 could counter the inhibitory effects of EA stimulation of HIRI in rats. Together, our findings indicate that EA stimulation at GB34 down-regulates the expression of ET-1, which inhibits the TAK1-JNK/p38 signaling pathway, consequently alleviating HIRI in rats.

Hepatic ischemia reperfusion injury: effect of moderate intensity exercise and oxytocin compared to l-arginine in a rat model

BackgroundHepatic ischemia reperfusion (IR) injury is considered as a main cause of liver damage and dysfunction. The l-arginine/nitric oxide pathway seems to be relevant during this process of IR. Although acute intense exercise challenges the liver with increased reactive oxygen species (ROS), regular training improves hepatic antioxidant status. Also, oxytocin (Oxy), besides its classical functions, it exhibits a potent antistress, anti-inflammatory, and antioxidant effects. This study was designed to evaluate the hepatic functional and structural changes induced by hepatic IR injury in rats and to probe the effect and potential mechanism of moderate intensity exercise training and/or Oxy, in comparison to a nitric oxide donor, l-arginine, against liver IR-induced damage.ResultsCompared to the sham-operated control group, the hepatic IR group displayed a significant increase in serum levels of ALT and AST, plasma levels of MDA and TNF-α, and significant decrease in plasma TAC and nitrite levels together with the worsening of liver histological picture. L-Arg, Oxy, moderate intensity exercise, and the combination of both Oxy and moderate intensity exercises ameliorated these deleterious effects that were evident by the significant decrease in serum levels of ALT and AST, significant elevation in TAC and nitrite, and significant decline in lipid peroxidation (MDA) and TNF-α, besides regression of histopathological score regarding hepatocyte necrosis, vacuolization, and nuclear pyknosis. Both the moderate intensity exercise-trained group and Oxy-treated group showed a significant decline in TNF-α and nitrite levels as compared to l-Arg-treated group. The Oxy-treated group showed statistical insignificant changes in serum levels of ALT, AST, and plasma levels of nitrite, MDA, TAC, and TNF-α as compared to moderate intensity exercise-trained group.ConclusionThe combination of both moderate intensity exercise and Oxy displayed more pronounced hepatoprotection on comparison with l-Arg which could be attributed to their more prominent antioxidant and anti-inflammatory effects but not due to their NO-enhancing effect.

Melatonin attenuates hepatic ischemia-reperfusion injury in rats by inhibiting NF-κB signaling pathway

BackgroundThe sterile inflammatory response is one of the key mechanisms leading to hepatic ischemia-reperfusion injury. Melatonin has been shown to prevent organ injuries, but its roles in the inflammatory response after hepatic ischemia-reperfusion injury have not been fully explored, especially in late ischemia-reperfusion injury. The present study aimed to investigate the roles and possible mechanisms of melatonin in the inflammatory response after hepatic ischemia-reperfusion injury. MethodsSixty Sprague-Dawley rats were randomly divided into a sham group, ischemia-reperfusion injury group (I/R group), and melatonin-treated group (M + I/R group). The rats in the I/R group were subjected to 70% hepatic ischemia for 45 min, followed by 5 or 24 h of reperfusion. The rats in the M + I/R group were injected with melatonin (10 mg/kg, intravenous injection) 15 min prior to ischemia and immediately before reperfusion. Serum and samples of ischemic liver lobes were harvested for future analysis, and the 7-day survival rate was assessed after hepatic ischemia-reperfusion surgery. ResultsIn comparison with the I/R group, the M + I/R group showed markedly decreased expression levels of inflammatory cytokines (IL-6 and TNF-α) and numbers of apoptotic hepatocytes (P < 0.05). Immunoblotting showed that the expression levels of IL-6, p-NF-κBp65/t-NF-κBp65 and p-IκB-α/t-IκB-α in the M + I/R group were significantly lower than those in the I/R group, and immunofluorescence staining showed that the expression level of p-NF-κBp65 in the M + I/R group was lower than that in the I/R group (P < 0.05). The 7-day survival rates were 20% in the I/R group and 50% in the M + I/R group (P < 0.05). ConclusionsMelatonin downregulated the activity of the NF-κB signaling pathway in the early and late stages of hepatic ischemia-reperfusion injury, alleviated the inflammatory response, protected the liver from ischemia-reperfusion injury, and increased the survival rate.

Targeting autophagy to modulate hepatic ischemia/reperfusion injury: A comparative study between octreotide and melatonin as autophagy modulators through AMPK/PI3K/AKT/mTOR/ULK1 and Keap1/Nrf2 signaling pathways in rats

Hepatic ischemia-reperfusion (HIR) injury is a common pathophysiological process in many clinical settings. This study was designed to compare the protective role of octreotide (somatostatin analogue, OCT) and melatonin (N-acetyl-5-methoxytryptamine, MLT) through the modulation of autophagy against HIR injury in rats. Male albino rats were divided into sham, HIR, OCT at three doses (50, 75, and 100 μg/kg), MLT, MLT + OCT75, compound C (AMPK inhibitor, CC), and CC + OCT75 groups. Ischemia was induced for 30 min followed by 24 h reperfusion. Biochemical, histopathological, immunohistochemical, lipid peroxidation, ELISA, qPCR, and western blot techniques were performed in our study. Liver autophagy was restored by OCT at doses (50 or 75 μg/kg) as indicated by elevating the expressions of Beclin-1, ATG7, and LC3 accompanied by the reduction of p62 expression through induction of AMPK/S317-ULK1 and inhibition of PI3K/AKT/mTOR/S757-ULK1 signaling pathways. As well, OCT maintained the integrity of the Keap1-Nrf2 system for the normal hepatic functions via controlling the Keap1 turnover through autophagy in a p62-dependent manner, resulting in upholding a series of anti-oxidant and anti-inflammatory cascades. These effects were abolished by compound C. On the other hand, MLT showed a decrease in the autophagy markers via inhibiting AMPK/pS317-ULK1 and activating PI3K/AKT/mTOR/pS757-ULK1 pathways. Autophagy inhibition with MLT markedly reversed the hepatoprotective effects of OCT75 after HIR injury. Finally, our results proved for the first time that OCT75 was more effective than MLT as it was sufficient to induce protective autophagy in our HIR model, which led to the induction of Nrf2-dependent AMPK/autophagy pathways.

The protective effect of glycyrrhizin on hepatic ischemia-reperfusion injury in rats and possible related signal pathway.

Objective(s):To investigate the protective effect of glycyrrhizin (GL) on hepatic ischemia-reperfusion injury (HIRI).Materials and Methods:Forty SD rats were randomly divided into sham group, HIRI group, GL 100 mg/kg group, and GL 200 mg/kg group. The pathological alterations of liver tissue in each group were observed. The levels of alanine transaminase (ALT), aspartate aminotransferase (AST), endothelin-1 (ET-l), nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) were detected. Western blot was used to detect the expression levels of cytoplasmic protein caspase-3, Bax, Bcl-2, heme oxygenase-1 (HO-1), nuclear factor erythroid 2-related factor 2 (Nrf2), and nuclear protein Nrf2.Results:Compared with the HIRI group, the levels of AST, ALT, ET-1, TNF-α, IL-1β, and IL-6 in GL groups were lower, serum NO content was higher, MDA content was lower, SOD and GSH-Px activities were significantly increased, apoptosis index was lower (P<0.05), which was more obvious in high-dose GL (200 mg/kg) group. The LC3-II/LC3-I ratio and Beclin-1 protein expression levels in the GL group were significantly lower than the HIRI group, but the expression levels of cytoplasmic protein HO-1 and nuclear protein Nrf2 were significantly higher than those of the HIRI group, which was more obvious in the high-dose GL group (P<0.05).Conclusion:GL has a protective effect on the liver of HIRI rats, and its mechanism may be related to activation of the Nrf2/HO-1 signaling pathway, inhibition of oxidative stress, inflammation, autophagy, and apoptosis.

Effect of irisin postconditioning on hepatic ischemia reperfusion injury in rats

Objective To investigate the effect and mechanism of irisin postconditioning on hepatic ischemia reperfusion injury in rats. Methods Totally 36 SD rats were randomly divided into sham group (S), model group (I/R) and irisin group (Ir), with 12 rats in each group. Hepatic ischemia was constructed in model group and irisin group by ligating left middle lobe of liver vascular branches for 60 min. Irisin was administered at the beginning of reperfusion by intravenous injection at the concentration of 10 μg/kg for rats in irisin group. We only dissected the hepatic duodenal ligament of rats in the S group. Serum and liver tissues were collected at 6 h after reperfusion through the inferior chamber. The serum levels of alanine aminotransferase (ALT), glutamic oxalacetic transaminase (AST), interleukin (IL)-6, IL-1βand tumor necrosis factor-α (TNF-α) were examined. The contents of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPX) in liver tissue were measured. The pathological changes of liver tissue were observed by hematoxylin and eosin (HE) staining. The phosphorylations of janus kinase 2 (JAK2), signal transducer and activators of transcription 3 (STAT3) and B cell lymphoma/leukemia-2 (bcl-2), bcl-2 associated X protein (bax), cysteinyl aspartate-specific protease (Caspase)-3 were assessed by Western blotting. Results The ALT levels in S group, I/R group and irisin group were as follows: (75.24±2.65), (705.33±4.02), (385.46±3.58) U/L; The AST levels were as follows: (122.33±6.76), (1 357.54±5.23), (738.26±3.98) U/L; The IL-6 levels were as follows: (104±16), (586±86), (275±35) ng/L; The TNF-α levels were as follows: (92±10), (1 165±102), (511±73) ng/L; The IL-1β levels were as follows: (98±12), (610±79), (312±41) ng/L; The MDA contents were as follows: (174±38), (1 900±460), (1 055±266) ng/L; The SOD contents were as follows: (124±10), (46±8), (70±10) ng/L; The GPX contents were as follows: (106±12), (42±5), (62±11) ng/L; The Caspase-3 levels were as follows: (0.22±0.06), (0.86±0.14), (0.57±0.11) ng/L; The p-JAK2 levels were as follows: 0.44±0.05, 0.91±0.07, 0.62±0.11; The p-STAT3 levels were as follows: 0.35±0.04, 0.86±0.08, 0.57±0.07. As compared with the sham group, the levels of ALT, AST, IL-6, TNF-α, IL-1β, MDA and Caspase-3 were significantly increased (t=445.551, 219.362, 21.700, 7.700, 36.182, 14.132, 24.191, 10.111, 13.753, 7.023, 14.456 and 6.556, P<0.01). The activities of GPX and SOD in model group and irisin group were significantly decreased (t=20.374, 14.104, 15.945 and 10.965, P<0.01), and the pathological damage worsened and the expression levels of activated p-JAK2 and p-STAT3were up-regulated in other groups (t=14.289, 5.479, 19.054 and 8.224, P<0.01); As compared with model group, the levels of ALT, AST, IL-6, TNF-α, IL-1β, MDA and Caspase-3 in irisin group were significantly decreased (t=226.183, 14.000, 14.081, 22.052 and 7.906, P<0.01), and pathological damage was alleviated and the expression levels of activated SOD and GPX significantly increased (t=6.274 and 4.985, P<0.01). The p-JAK2 and p-STAT3 were down-regulated in irisin group (t=8.819 and 10.834, P<0.01). Conclusion Exogenous irisin postconditioning can significantly decrease hepatic ischemia-reperfusion injury in rats by suppressing oxidative stress and cell apoptosis, and the mechanism may be associated with the suppression of JAK2/STAT3 signaling activation. Key words: Irisin; Hepatic ischemia; Reperfusion injury; Janus kinase 2; Signal transducer and activators of transcription 3

Protective effect and mechanism of alpha-lipoic acid on partial hepatic ischemia-reperfusion injury in adult male rats.

In order to reduce tissue damage caused by ischemia-reperfusion injury, this study aims to investigate the protective effect and mechanism of ?-lipoic acid on hepatic ischemia-reperfusion injury in rats. The bloodstream of rats was blocked in the left middle and left lateral liver lobes of the liver. Forty rats were randomly divided into two groups: treatment group and injury group. Rats were injected with either 25 mg/1 ml of alpha-lipoic acid (treatment group) or 1 ml of saline (injury group) into the caudal vein 15 min before hepatic ischemia-reperfusion. Rat serum alanine aminotransferase (GPT), glutathione (GSH) and superoxide dismutase (SOD) levels were examined at various time points (1, 3, 6 and 12 h) in both groups. Changes in nuclear factor kappa B P65 (NF-kappaB P65) expression in ischemia-reperfusion liver at various time points after reperfusion (1, 3, 6 and 12 h) were evaluated through immunohistochemistry assay. Changes in macrophage inflammatory protein-2 (MIP-2) mRNA and inducible nitric oxide synthase (iNOS) mRNA expression in ischemic reperfused rat livers were detected by RT-PCR. Serum GPT level was significantly higher in the injury group than in the treatment group (P<0.01). NF-kappaB P65, MIP-2 mRNA and iNOS mRNA expression in ischemic reperfused rat livers were significantly higher in the injury group than in the treatment group (P<0.01). Serum GSH and SOD levels were higher in the treatment group than in the injury group (P<0.01). Alpha-lipoic acid significantly reduced ischemia-reperfusion injury in rat livers. This may be associated to the direct scavenging of oxygen-free radicals, increased GSH production, and the activation of downstream media due to decreased NF-kappaB and GSH consumption.

Recombinant thrombomodulin prevented hepatic ischemia-reperfusion injury by inhibiting high-mobility group box 1 in rats

Recombinant thrombomodulin (rTM) is a novel anticoagulant and anti-inflammatory agent that inhibits secretion of high-mobility group box 1 (HMGB1) from liver. We evaluated the protective effects of rTM on hepatic ischemia-reperfusion injury in rats. Ischemia was induced by clamping the portal vein and hepatic artery of left lateral and median lobes of the liver. At 30 min before ischemia and at 6 h after reperfusion, 0.3 ml of saline (IR group) or 0.3 ml of saline containing 6 mg/kg body weight of rTM (IR-rTM group) was injected into the liver through inferior vena cava or caudate vein. Blood flow was restored at 60 min of ischemia. Blood was collected 30 min prior to induction of ischemia and before restoration of blood flow, and at 6, 12, and 24 h after reperfusion. All the animals were euthanized at 24 h after reperfusion and the livers were harvested and subjected to biochemical and pathological evaluations. Serum levels of ALT, AST, and HMGB1 were significantly lower after reperfusion in the IR-rTM group compared to IR group. Marked hepatic necrosis was present in the IR group, while necrosis was almost absent in IR-rTM group. Treatment with rTM significantly reduced the expression of TNF-α and formation of 4-hydroxynonenal in the IR-rTM group compared to IR group. The results of the present study indicate that rTM could be used as a potent therapeutic agent to prevent IR-induced hepatic injury and the related adverse events.

Telluric acid ameliorates hepatic ischemia reperfusion-induced injury in rats: Involvement of TLR4, Nrf2, and PI3K/Akt signaling pathways

In past tellurium-based compounds had limited use, however, their therapeutic potential have been target of interest recently due to antioxidant and anti-inflammatory capabilities in experimental endotoxemia. Nevertheless, their potential hepatoprotective effect against ischemia reperfusion (IR) injury is still obscure. This study examined the possible hepatoprotective effect of telluric acid (TELL), one of tellurium-based compound, against the deteriorating effect hepatic IR injury in rats through directing toll like receptor-4 (TLR4) cascade, phosphoinositide 3-kinase(PI3K)/Akt axis, and nuclear erythroid-related factor-2 (Nrf-2) pathway as possible mechanisms contributed to TELL’s effect. Indeed, male Wistar rats were randomized into 3 groups: sham-operated, control IR and TELL (50 µg/kg). TELL was administrated once daily for seven consecutive days prior to the IR induction. Pretreatment with TELL attenuated hepatic IR injury as manifested by hampered plasma aminotransaminases and lactate dehydrogenase activities. Also, TELL opposed IR induced elevation in tissue expression/activity of high-mobility group box protein-1 (HMGB1), TLR4, myeloid differentiation primary-response protein 88 (MyD88), phospho-nuclear factor-kappa B p65 (p-NF-κB p65), phospho-mitogen activated protein kinasep38 (p-MAPKp38) and tumor necrosis factor-alpha (TNF-α). Moreover, TELL reduced the elevated thiobarbituric acid reactive substances along with increased both Nrf-2 and endothelial nitric oxide synthase (eNOS) protein expression, beside replenishment of hepatic reduced glutathione. In addition, TELL induced obvious upregulation of p-PI3K and p-Akt protein expressions together with restoration of histopathological changes in IR injury. In conclusion, TELL purveyed conceivable novel hepatoprotective mechanisms and attenuated events associated with acute hepatic injury via inhibition of TLR4 downstream axis and activation of Nrf-2 and PI3K/Akt signaling cascades. Thus, TELL may provide a novel therapeutic potential for complications of hepatic IR injury.

Hyperoside Attenuates Hepatic Ischemia-Reperfusion Injury by Suppressing Oxidative Stress and Inhibiting Apoptosis in Rats

PurposeHepatic ischemia-reperfusion (IR) injury is a serious complication of many clinical conditions, which may lead to liver or multiple organ failure. Hyperoside, a flavonoid compound, has been reported to protect against myocardial and cerebral injury induced by IR. This study aimed to investigate the protective effects of hyperoside on hepatic IR injury in rats. MethodsUsing the 70% hepatic IR injury model, we divided 32 male Wistar rats into 4 groups (n = 8): sham-operated, IR+saline (saline/p.o.), IR+vehicle (carboxy methyl cellulose/p.o.), and IR+hyperoside (50 mg/kg/d/p.o.). At 24 hours after reperfusion, blood and liver tissue were collected. The effects of hyperoside on hepatic IR injury were assessed through tests of serum transaminase, hepatic histopathology, and measurement of markers of oxidative stress and apoptosis. ResultsPretreatment with hyperoside protected the liver from IR injury by a reduction in serum aspartate aminotransferase/alanine aminotransferase levels and a decrease in the severity of histologic changes. Hyperoside treatment also decreased the activity of malondialdehyde, increased the activities of superoxide dismutase and glutathione peroxidase, up-regulated the expression of heme oxygenase 1 and NAD(P)H:quinone oxidoreductase 1, and reduced the apoptotic index after IR injury. A decrease in the expression of caspase–3 and an increase in the ratio of B cell lymphoma 2 to B cell lymphoma 2–associated X also were observed. ConclusionHyperoside has a protective effect on hepatic IR injury in rats, which may be due to its antioxidant and antiapoptotic properties.

Pre-treatment with FK506 reduces hepatic ischemia-reperfusion injury in rats

The study is aimed to investigate the protective effects and possible mechanism of tacrolimus (FK506) pre-treatment in hepatic ischemia-reperfusion injury in rats. The rats were randomly assigned into four groups, which were S, IR, L and H group, and then all groups were subjected to 60min of 70% partial warm liver ischemia, except S group. Rats in the L and H group were pre-treated with two different doses FK506 at 60min before ischemia. The rats of the IR group received an identical volume of normal saline. All animals were sacrificed after 6h of reperfusion. Transaminases were measured by biochemistry analyzer. Elisa kit was used to detect TNF-α, IL-6 and IL-1β levels in serum. Liver specimens were stained with hematoxylin and eosin (HE) to assess the pathologic changes. The expressions of heme oxygenase-1 (HO-1), hypoxia-inducible factor-1α (HIF-1α), nuclear factor of activatedT cells (NFAT3) were measured by real-time quantitative PCR and western blotting and the Bcl-2 and the Bax protein were tested by western blotting. In rats pre-treated with FK506, the levels of transaminases, TNF-α and IL-1β were reduced significantly and also liver damage was dramatically mitigated compared to those without FK506 pre-treatment. Moreover, the expression of HO-1 at the level of both transcription and translation increased clearly and the activation of the HIF-1α was found in FK506 pre-treated livers. Moreover, NFAT3 protein transportation to the nucleus was reduced and Bax protein expression was decreased, but the expression of Bcl-2 protein was markedly increased after FK506 pre-treatment. FK506 pre-treatment could lessen hepatic ischemia-reperfusion injury through up-regulating the expression of HIF-1α and HO-1, and inhibiting nuclear translocation of NFAT3 in liver tissues.

Effect of sevoflurane on hepatic ischemia-reperfusion injury in rats via JAK2-STAT3 pathway.

To investigate the effect of sevoflurane on hepatic ischemia-reperfusion injury in rats via janus kinase 2/signal transducer and activator of transcription 3 (JAK2-STAT3) pathway. Forty healthy male Sprague-Dawley (SD) rats were randomly divided into sham group (n=10), model group (HIRI group, n=10), sevoflurane intervention group (SF group, n=10), and sevoflurane combined with AG490 intervention group (AG490 group, n=10). Liver and serum samples were collected after reperfusion for 6 h. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP), interleukin (IL) -1β, IL-6 and tumor necrosis factor (TNF) -α were detected by enzyme-linked immunosorbent assay (ELISA). JAK2, STAT3, p-JAK2 and p-STAT3 were detected by Western-blot. The expression level of cobalt quenching technique was used to detect the permeability of mitochondrial membrane permeability transition pore (mPTP). The levels of ALT, AST, AKP, IL-1β, IL-6 and TNF-α in HIRI group were higher than those in sham group (p < 0.05), those in SF group were lower than those in HIRI group (p < 0.05), while those in AG490 group were higher than those in SF group (p < 0.05). The levels of JAK2 protein, pJAK2 protein, STAT3 protein and P STAT3 protein in HIRI group were lower than those in sham group (p < 0.05); the levels of each protein in SF group were higher than those in HIRI group (p < 0.05), while those in AG490 group were lower than those in SF group (p < 0.05). The open degree of HIRI group was higher than that of sham group (p < 0.05); SF group was lower than that of HIRI group, and AG490 group was higher than that of SF group (p < 0.05). Sevoflurane can significantly improve HIRI and reduce hepatic immune inflammation in rats. The mechanism may be related to activating JAK2-STAT3 pathway and inhibiting the overopening of mPTP.