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Objective(s): Gallic acid (GA) is a highly effective antioxidant, which its beneficial effects are well known, but its impact on expression of microRNAs (miRs) following hepatic ischemia-reperfusion (I/R) is not well recognized. Therefore, the current research was designed to specify the beneficial effect of GA on miRs (122 and 34a), liver functional tests, and histopathological alterations beyond I/R-induced hepatic injury. Materials and Methods: Thirty-two rats were randomly divided into four groups (8 per group) including: sham-operated (S), I/R, and GA+I/R pretreated groups. Rats in sham-operated group received physiologic saline (N/S, 2 ml/kg), on a weekly basis, once a day via intraperitoneally route), then a midline abdominal surgery was performed. IR, and GA+IR pretreated groups received physiologic saline (2 ml/kg), and GA (50, and 100 mg per kg) for same time, IP, respectively, before induction of transient ischemia. One hour after reperfusion, biochemical, and histopathological evaluations were performed and expression of miRs were evaluated.Results: The results showed that GA reduced the concentrations of liver enzymes, miR-122, and miR-34a in serum, and preserved liver cells changes induced by I/R injury.Conclusion: These findings showed that GA has beneficial effect on liver damage induced by I/R. Therefore, it is suggested that GA can be administered as an anti-miR before elective hepatic surgeries for prevention of this complication.

Hepatic ischemia-reperfusion (IR) injury is characterized by severe inflammation and cell death. However, very few effective therapies are presently available for hepatic IR injury treatment. Here, we reported a protective function and the underlying mechanism of myotubularin-related protein 14 (MTMR14) during hepatic IR injury. Hepatocyte-specific MTMR14 knockout (HKO) and transgenic (TG) mice were subjected to hepatic IR operation to explore MTMR14 function in vivo. Primary hepatocytes isolated from MTMR14-HKO and MTMR14-TG mice were subjected to hypoxia/reoxygenation (HR) insult in vitro. We found that MTMR14 expression in liver tissues from individuals with hepatic IR was markedly decreased, and similar results were detected in mice with hepatic IR surgery. MTMR14-TG mice following hepatic IR operation had obviously ameliorated liver pathological changes, along with improved hepatic dysfunction, which was proved by the decreased serum alanine amino transferase (ALT) and aspartate amino transferase (AST) levels. MTMR14-HKO and MTMR14-TG animal models indicated that MTMR14 alleviated cell death and inflammatory response. In addition, MTMR14 inhibited nuclear transcription factor κB (NF-κB) signaling. Of note, promoting MTMR14 expression improved phosphatidylinositol 3-kinase/protein kinase-B (PI3K/AKT) pathway through a physical interaction with AKT, subsequently reducing cell death and inflammation. Therefore, MTMR14 is a protective factor during hepatic IR injury, and the MTMR14/AKT signaling is involved the pathogenesis hepatic IR injury. Improvement of this axis might be a novel therapeutic strategy for the prevention of this pathological process.

Objective(s): Gallic acid (GA) is a highly effective antioxidant, which its beneficial effects are well known, but its impact on expression of microRNAs (miRs) following hepatic ischemia-reperfusion (I/R) is not well recognized. Therefore, the current research was designed to specify the beneficial effect of GA on miRs (122 and 34a), liver functional tests, and histopathological alterations beyond I/R-induced hepatic injury. Materials and Methods: Thirty-two rats were randomly divided into four groups (8 per group) including: sham-operated (S), I/R, and GA+I/R pretreated groups. Rats in sham-operated group received physiologic saline (N/S, 2 ml/kg), on a weekly basis, once a day via intraperitoneally route), then a midline abdominal surgery was performed. IR, and GA+IR pretreated groups received physiologic saline (2 ml/kg), and GA (50, and 100 mg per kg) for same time, IP, respectively, before induction of transient ischemia. One hour after reperfusion, biochemical, and histopathological evaluations were performed and expression of miRs were evaluated. Results: The results showed that GA reduced the concentrations of liver enzymes, miR-122, and miR- 34a in serum, and preserved liver cells changes induced by I/R injury. Conclusion: These findings showed that GA has beneficial effect on liver damage induced by I/R. Therefore, it is suggested that GA can be administered as an anti-miR before elective hepatic surgeries for prevention of this complication. [ABSTRACT FROM AUTHOR]

This present study was aimed to investigate the molecular mechanisms involved in sevoflurane protection of hepatic ischemia-reperfusion (I/R) injury. Firstly, we investigated the protective effects of sevoflurane against hepatic I/R injury. Biochemical analysis results showed that sevoflurane preconditioning significantly protected against hepatic I/R injury by reducing liver enzymes and improving antioxidant defense markers. We also found that sevoflurane attenuates I/R-induced hepatic cell death, by TUNEL staining, DNA fragmentation ELISA and PARP activity determination. Next, In order to find the molecular mechanism of sevoflurane preconditioning in hepatic I/R injury, we poured our attention to microRNAs regulation. We focused on miR-200c, one of microRNAs which screened from the gene expression omnibus (GEO). Furthermore, a hydrogen peroxide (H 2 O 2 )-induced oxidative stress apoptosis model was also established to mimic hepatic I/R injury, the effects of MiR-200c was investigated. We observed that MiR-200c inhibition decreased the H 2 O 2 -induced apoptosis of hepatic AML-12 cells. And also, ZEB1 is found as a target gene of miR-200c and is involved in H 2 O 2 -induced apoptosis. On the other hand, the in vivo model was established to examine whether sevoflurane protect against hepatic IR injury by downregulating MiR-200c. Together with the biochemical tests and apoptosis detection, results showed that over-expression of miR-200c significantly inhibited the protect effect of sevoflurane in Hepatic IR injury. Summarizing, sevoflurane preconditioning seems to ameliorate hepatic I/R injury in mice, mediated by mechanisms that include microRNA 200c down regulation. However, further more studies need to be carried out to verify this point. [ABSTRACT FROM AUTHOR]

We investigated the organ-reducing ability of 1,2-dihydro-2,6-dimethyl-4-(3-nitrophenyl)-3,5-pyridine-dicarboxylic acid methyl 6-(5-phenyl-3-pyrazolyloxy) hexyl ester (CV159) that exhibits selective blocking of Ca2+/calmodulin and inhibition of Ca2+ overloading in living organisms (Sprague Dawley rats) using an in vivo and an ex vivo electron paramagnetic imaging technique. Decay rates in CV159-treated rats were significantly higher than those in untreated rats and were almost equal to those in the sham group. Both cytosol and mitochondrial superoxide scavenging activity in CV159-treated rats were significantly higher than those in untreated rats, and cytosol superoxide scavenging activity only was slightly higher than that in the sham group. Faint staining for anti-superoxide dismutase antibody was markedly observed in necrotic lesions in the liver of control group. Alanine aminotransferase level in CV-treated rats were significantly decreased as compared with the levels in untreated rats. Electron microscopy showed a decreased number of damaged mitochondria, whereas mitochondrial damage was significantly reduced in CV-treated animals. We conclude that CV159 retains the organ-reducing activity against radicals in hepatic I/R injury that is mediated by the inhibition of Ca2+ overloading. [Copyright &y& Elsevier]

Background: Experimental abdominal aortic aneurysm (AAA) development can be pharmacologically suppressed by inhibiting matrix metalloproteinase-9 (MMP-9). Cyclooxygenase-2 (COX-2) inhibitors are potent anti-inflammatory agents that have been demonstrated to inhibit experimental aneurysm development. We hypothesized that treatment with MF-tricyclic, a selective COX-2 inhibitor, incorporated into rodent chow would inhibit aneurysm development in a rat AAA model. Methods: Twelve male Sprague Dawley rats underwent induction of experimental AAA using intra-aortic porcine elastase infusion. Six rats received control feed, and six received MF-tricyclic rodent chow for a period of 14 days. Aortic diameters were measured pre- and postinfusion as well as at harvest. Aortic tissue samples were evaluated by real-time polymerase chain reaction (RT-PCR) for MMP-9, by immunohistochemistry for elastin. Results: Elastase infusion produced AAA in all untreated rats. At 14 days MF-tricyclic-treated rats had significantly reduced aortic diameter (1.9 ± 0.1 mm versus 2.4 ± 0.0 mm, P = 0.00001). Percent increase in aortic diameter was also significantly less in animals receiving MF-tricyclic (65.7 ± 8.5% versus 132.3 ± 7.3%, P = 0.0001). RT-PCR demonstrated a decrease in the mean expression of MMP-9 in the treated animals (0.414 ng of RNA versus 1.114 ng of RNA) (P = 0.07). Sections stained for elastin demonstrated preserved elastin integrity in MF-tricyclic treated aortas. Conclusions: COX-2 inhibition helps to retard the growth of experimental AAAs possibly through inhibition of MMP-9. Experimentally treated animals demonstrated smaller aortic diameters and lower levels of tissue MMP-9 when compared to untreated animals. Selective COX-2 inhibition may offer an additional method to pharmacologically inhibit AAAs. [Copyright &y& Elsevier]

• MTMR14 inhibits ischemia reperfusion (IR) injury-triggered hepatic dysfunction and cell death. • MTMR14 suppresses IR-triggered hepatic inflammation. • MTMR14 interacts with AKT to meditate cell death and inflammation during hepatic IR injury. Hepatic ischemia-reperfusion (IR) injury is characterized by severe inflammation and cell death. However, very few effective therapies are presently available for hepatic IR injury treatment. Here, we reported a protective function and the underlying mechanism of myotubularin-related protein 14 (MTMR14) during hepatic IR injury. Hepatocyte-specific MTMR14 knockout (HKO) and transgenic (TG) mice were subjected to hepatic IR operation to explore MTMR14 function in vivo. Primary hepatocytes isolated from MTMR14-HKO and MTMR14-TG mice were subjected to hypoxia/reoxygenation (HR) insult in vitro. We found that MTMR14 expression in liver tissues from individuals with hepatic IR was markedly decreased, and similar results were detected in mice with hepatic IR surgery. MTMR14-TG mice following hepatic IR operation had obviously ameliorated liver pathological changes, along with improved hepatic dysfunction, which was proved by the decreased serum alanine amino transferase (ALT) and aspartate amino transferase (AST) levels. MTMR14-HKO and MTMR14-TG animal models indicated that MTMR14 alleviated cell death and inflammatory response. In addition, MTMR14 inhibited nuclear transcription factor κB (NF-κB) signaling. Of note, promoting MTMR14 expression improved phosphatidylinositol 3-kinase/protein kinase-B (PI3K/AKT) pathway through a physical interaction with AKT, subsequently reducing cell death and inflammation. Therefore, MTMR14 is a protective factor during hepatic IR injury, and the MTMR14/AKT signaling is involved the pathogenesis hepatic IR injury. Improvement of this axis might be a novel therapeutic strategy for the prevention of this pathological process. [ABSTRACT FROM AUTHOR]