\n\nMain methods: Animals were fed an ethanol liquid diet or isocaloric control diet for 5 weeks. Isolated perfused rat livers were preserved in Histidine-Tryptophan-Ketoglutarate at 4 degrees C. After 24 h of storage, livers were subjected to 120 min of reperfusion with Krebs-Henseleit bicarbonate buffer at 37 degrees C. Animals were pre-treated with cobalt protoporphyrin (CoPP, 5 mg/kg, i.p.) or zinc protoporphyrin (ZnPP,
25 mg/kg, i.p.), HO-1 inducer and antagonist, respectively.\n\nKey findings: In the model of ischemia/isolated perfusion, endogenous HO-I was downregulated in the livers fed with ethanol diet (ED I/R). In ED I/R group, portal pressure and lactate dehydrogenase release were significantly increased, while bile output and hyaluronic acid clearance selleckchem decreased compared to rats fed on control diet (CD I/R). Furthermore, hepatic glutathione content decreased and lipid peroxidation increased
in the ED I/R group compared to the CD I/R group. These alterations were attenuated by upregulation of HO-1 with CoPP pretreatment.\n\nSignificance: Our results suggest that chronic ethanol consumption aggravates hepatic injury during cold I/R and it is likely due to downregulation of endogenous HO-1. Prior induction of HO-1 expression may provide a new strategy to protect livers against hepatic I/R injury or to increase the donor transplant pool
through modulation of marginal CUDC-907 alcoholic steatotic livers. (c) 2011 Elsevier Inc. All rights reserved.”
“Global epidemic studies have suggested that coffee consumption is reversely correlated with the incidence selleck kinase inhibitor of type 2 diabetes mellitus (T2DM), a metabolic disease. The misfolding of human islet amyloid polypeptide (hIAPP) is regarded as one of the causative factors of T2DM. Coffee extracts have three major active components: caffeine, caffeic acid (CA), and chlorogenic acid (CGA). In this study, the effects of these major coffee components, as well as dihydrocaffeic acid (DHCA) (a major metabolite of CGA and CA), on the amyloidogenicity of hIAPP were investigated by thioflavin-T based fluorescence emission, transmission electronic microscopy, circular dichroism, light-induced cross-linking, dynamic light scattering, and MTT-based cell viability assays. The results suggest that all components show varied inhibitory effects on the formation of toxic hIAPP amyloids, in which CA shows the highest potency in delaying the conformational transition of the hIAPP molecule with the most prolonged lag time, whereas caffeine shows the lowest potency. At a 5-fold excess molar ratio of compound to hIAPP, all coffee-derived compounds affect the secondary structures of incubated hIAPP as suggested by the circular dichroism spectra and CDPro deconvolution analysis.