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Abstract: Chronic hypoxia usually evokes sustained release of endogenous neurohormones, leading to β2-adrenergic receptor (β2AR) desensitization and downregulation of expression, which impacts cellular contractility. We investigated whether exogenous β2AR could compensate for the functional deficiency of β2AR in rabbit cardiomyocytes under chronic hypoxia, and whether this led to improved contractility and cellular survival. A surgical experimental model of cyanotic heart disease was established in rabbits. Adv.hβ2AR was transfected into cardiomyocytes isolated from animals subjected to 6-week systemic hypoxia. The levels of cellular contractile function, protein expression of hβ2AR, p-Akt, p-Erk, and caspase-3, and cellular survival pre- and post-Adv.hβ2AR delivery were determined. In the cyanotic cells, decreased shortening and lengthening of TPC and R50 were evident. Cellular diastolic functioning showed greater deterioration compared to the systolic function (P <0.05). In cyanotic cells, the positive inotropic response to isoproterenol was decreased (P <0.01), low levels of cellular survival were found, protein levels of β2AR, p-Akt, and p-Erk were downregulated, and protein levels of caspase-3 were upregulated. After Adv.hβ2AR delivery, enhanced contractile function was achieved (P <0.01), TPC and R50 levels recovered up to 99% and 81.7% of the normal control levels, respectively (P <0.05), and cellular survival improved (P <0.01). Our results demonstrate that overexpression of the β2AR gene in cardiomyocytes exposed to chronic hypoxia provides significant catecholamine-dependent inotropic support and cellular protection. [ABSTRACT FROM AUTHOR]

C-type lectin-like receptors (CLRs) are important pathogen pattern recognition molecules that recognize carbohydrate structures. However, the functions of these receptors in fish keep less known. In this study, we characterized a novel CLR from a teleost fish, Plecoglossus altivelis (ayu), tentatively named PaCD209L. The cDNA of PaCD209L is 1464 nucleotides (nts) in length, encoding a polypeptide of 281 amino acid residues with a calculated molecular weight of 31.5 kDa. Multiple alignment of the deduced amino acid sequences of PaCD209L and other related fish CLRs revealed that the PaCD209L sequence had typical characteristics of fish CLRs, but without Ca 2+ -binding sites. Sequence comparison and phylogenetic tree analysis showed that PaCD209L shared the highest amino acid identity (44%) with rainbow trout ( Oncorhynchus mykiss ) CD209 aE PaCD209L transcripts were detected in all of the tissues examined, mainly expressed in the brain and heart. Upon Vibrio anguillarum infection, PaCD209L transcripts were upregulated in all tested tissues and in monocytes/macrophages (MO/MΦ). We prepared recombinant PaCD209L (rPaCD209L) by prokaryotic expression and raised antiserum against PaCD209L. Western blot analysis revealed that native PaCD209L was glycosylated, and its protein expression significantly increased in ayu MO/MΦ upon V. anguillarum infection. In addition, rPaCD209L was able to bind Gram-positive and Gram-negative bacteria in the absence of Ca 2+ . After PaCD209L was blocked by anti-PaCD209L IgG, the phagocytosis and bacterial killing activity of MO/MΦ significantly decreased. These results suggest that PaCD209L plays an important role in the regulation of MO/MΦ functions in ayu. [ABSTRACT FROM AUTHOR]

Abstract: Background: Cell proliferation, renewal, and apoptosis factors are related to hemorrhagic shock (HS) survival. Objective: Hepatic gene expression before and 24 h after induced HS were compared. Methods: Male Sprague-Dawley rats aged 8–9 wk (n = 11) were subjected to blood loss, and HS was induced in 9 rats (blood loss <0.1 mL) by left lobular hepatectomy with fixed-volume blood loss (2.5 mL/100 g) for this self-controlled study. In 3 randomly selected rats surviving >24 h post-HS, hepatic tissue samples collected pre-HS (n = 3; group A) and 24 h post-HS (n = 3; group B) were used for microarray analysis (21,793 genes) of differentially expressed genes using pathway, gene ontology, and network analyses. Real-time reverse transcriptase polymerase chain reaction confirmed Aldh1a1, Aldh1a7, amine oxidase, copper containing 3, cytochrome P450 26A1, histidine decarboxylase 1, and epoxide hydrolase 2 expression using a beta-actin reference. Results: Four rats survived 24 h after HS. Microarray revealed 562 upregulated and 634 downregulated genes in group A compared with group B. Gene ontology analysis revealed differentially expressed genes involved in cholesterol metabolic processes, extracellular stimuli response, sterol metabolic processes, hormonal stimuli response, steroid metabolic processes, endogenous stimulus response, oxidation and reduction reactions, organic substance response, and fatty acid metabolic processes. Conclusions: HS pathogenesis involves numerous interrelated signaling pathways. Redox reaction and fatty acid metabolism pathway involvement in traumatic HS recovery, as well as other pathways, may provide novel targets for better understanding the pathology of HS and developing treatments to limit post-HS organ failure. [Copyright &y& Elsevier]

Abstract: This study was to investigate whether sulforaphane (SFN) can prevent diabetic cardiomyopathy. Type 1 diabetes was induced in FVB mice by multiple intraperitoneal injections with low-dose streptozotocin. Hyperglycemic and age-matched control mice were treated with or without SFN at 0.5mg/kg daily in five days of each week for 3months and then kept until 6months. At 3 and 6months of diabetes, blood pressure and cardiac function were assessed. Cardiac fibrosis, inflammation, and oxidative damage were assessed by Western blot, real-time qPCR, and histopathological examination. SFN significantly prevented diabetes-induced high blood pressure and cardiac dysfunction at both 3 and 6months, and also prevented diabetes-induced cardiac hypertrophy (increased the ratio of heart weight to tibia length and the expression of atrial natriuretic peptide mRNA and protein) and fibrosis (increased the accumulation of collagen and expression of connective tissue growth factor and tissue growth factor-β). SFN also almost completely prevented diabetes-induced cardiac oxidative damage (increased accumulation of 3-nitrotyrosine and 4-hydroxynonenal) and inflammation (increased tumor necrotic factor-α and plasminogen activator inhibitor 1 expression). SFN up-regulated NFE2-related factor 2 (Nrf2) expression and transcription activity that was reflected by increased Nrf2 nuclear accumulation and phosphorylation as well as the mRNA and protein expression of Nrf2 downstream antioxidants. Furthermore, in cultured H9c2 cardiac cells silencing Nrf2 gene with its siRNA abolished the SFN''s prevention of high glucose-induced fibrotic response. These results suggest that diabetes-induced cardiomyopathy can be prevented by SFN, which was associated with the up-regulated Nrf2 expression and transcription function. [Copyright &y& Elsevier]

Abstract: Mutations in the parkin gene are the most common cause of autosomal recessive Parkinson’s disease (PD). As an E3-ubiquitin ligase, Parkin is associated with mitochondrial dynamics and mitophagy. Mortalin, a molecular chaperone, is located primarily in mitochondria, where it functions to maintain mitochondrial homeostasis and antagonize oxidative stress injury. A reduced expression level of mortalin has been observed in the affected brain regions of PD patients. Mortalin also interacts with a variety of PD-related proteins and plays an indispensible role in helping native protein refolding and importing proteins into the mitochondrial matrix. Thus, the main aims of the present study were to investigate mitochondrial dysfunction induced by knockdown of mortalin and to test whether Parkin overexpression could rescue this effect. We found that lentivirus-mediated knockdown of mortalin in HeLa cells resulted in a collapse of mitochondrial membrane potential, an abnormal accumulation of reactive oxygen species and apparent alterations in mitochondrial morphology under H2O2-induced stress conditions. Remarkably, Parkin overexpression rescued these mitochondrial abnormalities. In HeLa cells expressing Parkin, co-immunoprecipitation of endogenous mortalin and wild-type Parkin was detected when they were treated with carbonyl cyanide 3-chlorophenylhydrazone (CCCP). In conclusion, we indicate that the relatively decreased mortalin expression level and its impaired interaction with Parkin could affect its roles in mitochondrial function. [Copyright &y& Elsevier]