SREBP-1 and LXRα pathways mediated Cu-induced hepatic lipid metabolism in zebrafish Danio rerio.

The present study was performed to explore the underlying molecular mechanism of Cu-induced disorder of lipid metabolism in fish. To this end, adult zebrafish were exposed to three waterborne Cu concentrations (0 (control), 8 and 16 μg Cu/L, respectively) for 60 days. Hepatic Cu content and hepatosomatic index increased after waterborne Cu exposure.

Upstream regulators of apoptosis mediates methionine-induced changes of lipid metabolism.

Although the role of methionine (Met), as precursor for l-carnitine synthesis, in the regulation of lipid metabolism has been explored. Met seems to have tissue- and species-specific regulatory effect on lipid metabolism, implying that the mechanisms in Met regulation of lipid metabolism is complex and may involve the upstream regulatory pathway of lipid metabolism. The present study was performed to determine the mechanism of apoptosis signaling pathways mediating Met-induced changes of hepatic lipid deposition and metabolism in fish, and compare the differences of the mechanisms between the fish and mammals.

Zinc reduces hepatic lipid deposition and activates lipophagy via Zn/MTF-1/PPARα and Ca/CaMKKβ/AMPK pathways.

Zinc (Zn) deficiency is the most consistently discovered nutritional manifestations of fatty liver disease. Although Zn is known to stimulate hepatic lipid oxidation, little is known about its underlying mechanism of action in lipolysis. Given the potential role of lipophagy in lipid metabolism, the purpose of this study was to test the hypothesis that Zn attenuates hepatic lipid accumulation by modulating lipophagy.

Fatty Acid β-Oxidation Is Essential in Leptin-Mediated Oocytes Maturation of Yellow Catfish Pelteobagrus fulvidraco.

Although several studies have been conducted to study leptin function, information is very scarce on the molecular mechanism of leptin in fatty acid β-oxidation and oocytes maturation in fish. In this study, we investigated the potential role of fatty acid β-oxidation in leptin-mediated oocytes maturation in . Exp.

Six indicator genes for zinc (Zn) homeostasis in freshwater teleost yellow catfish Pelteobagrus fulvidraco: molecular characterization, mRNA tissue expression and transcriptional changes to Zn exposure.

Excessive Zn in the aquatic environment can be toxic and causes dysfunction in Zn homeostasis for fish, which ultimately influences the function of various biological processes. Zn homeostasis is controlled by Zn transporters. This study cloned and characterized the full-length cDNA sequences of six Zn transport-relevant genes (ZnT1, ZnT5, ZnT7, ZIP4, ZIP5 and MTF-1) from yellow catfish Pelteobagrus fulvidraco.

Oxidative stress and mitochondrial dysfunction mediated Cd-induced hepatic lipid accumulation in zebrafish Danio rerio.

The present study was performed to determine the effect of waterborne CdCl exposure influencing lipid deposition and metabolism, oxidative stress and mitochondrial dysfunction, and explore the underlying molecular mechanism of cadmium (Cd)-induced disorder of hepatic lipid metabolism in fish. To this end, adult zebrafish were exposed to three waterborne CdCl concentrations (0(control), 5 and 25 μg Cd/l, respectively) for 30 days. Lipid accumulation, the activities of enzymes related to lipid metabolism and oxidative stress, as well as the expression level of genes involved in lipid metabolism and mitophagy were determined in the liver of zebrafish.

Functional Analysis of Promoters from Three Subtypes of the PI3K Family and Their Roles in the Regulation of Lipid Metabolism by Insulin in Yellow Catfish Pelteobagrus fulvidraco.

In the present study, the length of 360, 1848 and 367 bp sequences of promoters from three subtypes of PI3K family (PI3KCa, PI3KC2b and PI3KC3) of yellow catfish were cloned and characterized. Bioinformatics analysis revealed that , and had different structures in their core promoter regions. The promoter regions of and had CpG islands but no CAAT and TATA box.

Identification of apoptosis-related genes Bcl2 and Bax from yellow catfish Pelteobagrus fulvidraco and their transcriptional responses to waterborne and dietborne zinc exposure.

Apoptosis plays a key role in the physiology of multicellular organisms, and has been well studied in mammals, but not in teleosts. Zinc (Zn) has been shown to be an important regulator of apoptosis and apoptosis involves in the regulation of lipid metabolism. Moreover, our recent study indicated that waterborne and dietborne Zn exposure differently influenced lipid metabolism in Pelteobagrus fulvidraco, but further mechanism remained unknown.

Endoplasmic reticulum (ER) stress and cAMP/PKA pathway mediated Zn-induced hepatic lipolysis.

The present study was performed to determine the effect of Zn exposure influencing endoplasmic reticulum (ER) stress, explore the underlying molecular mechanism of Zn-induced hepatic lipolysis in a fish species of significance for aquaculture, yellow catfish Pelteobagrus fulvidraco. We found that waterborne Zn exposure evoked ER stress and unfolded protein response (UPR), and activated cAMP/PKA pathway, and up-regulated hepatic lipolysis. The increase in ER stress and lipolysis were associated with activation of cAMP/PKA signaling pathway.

Identification of autophagy related genes LC3 and ATG4 from yellow catfish Pelteobagrus fulvidraco and their transcriptional responses to waterborne and dietborne zinc exposure.

Autophagy mediates the regulation of lipid metabolism. Moreover, our recent study indicated that waterborne and dietborne zinc (Zn) exposure differentially influenced lipid metabolism in a fish species of significance for aquaculture, yellow catfish Pelteobagrus fulvidraco, but further mechanism remained unknown. The hypothesis of the present study is that autophagy mediated the Zn-induced changes of lipid metabolism of yellow catfish subjected to different exposure pathways.

AKTs/PKBs: molecular characterization, tissue expression and transcriptional responses to insulin and/or wortmannin in yellow catfish Pelteobagrus fulvidraco.

In the present study, four AKT isoforms termed AKT1, AKT2, AKT3a and AKT3b were isolated and characterized from yellow catfish. Their molecular characterizations, tissue expressions and transcriptional responses to insulin and/or wortmannin were determined. The validated complementary DNA (cDNA) of yellow catfish AKT1, AKT2, AKT3a and AKT3b were 1422, 1431, 1389 and 1440 bp in length, encoding the peptide of 472, 475, 462 and 479 amino acid residues, respectively.

Role and mechanism of the AMPK pathway in waterborne Zn exposure influencing the hepatic energy metabolism of Synechogobius hasta.

Previous studies have investigated the physiological responses in the liver of Synechogobius hasta exposed to waterborne zinc (Zn). However, at present, very little is known about the underlying molecular mechanisms of these responses. In this study, RNA sequencing (RNA-seq) was performed to analyse the differences in the hepatic transcriptomes between control and Zn-exposed S.

IRS1 and IRS2: molecular characterization, tissue expression and transcriptional regulation by insulin in yellow catfish Pelteobagrus fulvidraco.

The insulin receptor substrate (IRS) proteins, in particular, IRS1 and IRS2, are the key downstream players of insulin signaling pathway and the regulation of lipid metabolism. In the present study, two genes of IRS (IRS1 and IRS2) were isolated and characterized from yellow catfish Pelteobagrus fulvidraco. Their molecular characterizations, tissue expressions, and transcriptional levels by insulin both in vivo and in vitro were determined.

Effects of waterborne Cu exposure on intestinal copper transport and lipid metabolism of Synechogobius hasta.

The present study was conducted to explore the effects of waterborne Cu exposure on intestinal Cu transport and lipid metabolism of Synechogobius hasta. S. hasta were exposed to 0, 0.

Effects and mechanisms of waterborne copper exposure influencing ovary development and related hormones secretion in yellow catfish Pelteobagrus fulvidraco.

The present study was conducted to determine the effects and mechanism of waterborne copper (Cu) exposure influencing ovary development and related hormones secretion in yellow catfish Pelteobagrus fulvidraco. To this end, two experiments were conducted. In Exp.

Five metal elements homeostasis-related genes in Synechogobius hasta: Molecular characterization, tissue expression and transcriptional response to Cu and Fe exposure.

Two isoforms of Cu transporter (CTR1 and CTR2) and metallothionein (MT1 and MT2), and divalent metal ion transporter 1 (DMT1) were cloned and characterized in Synechogobius hasta, respectively. The protein sequences of S. hasta CTRs possessed two methionine-rich regions (MxM and MxxxM) and three transmembrane regions.

Endoplasmic reticulum stress and dysregulation of calcium homeostasis mediate Cu-induced alteration in hepatic lipid metabolism of javelin goby Synechogobius hasta.

The present study was conducted to investigate the effect of Cu exposure on endoplasmic reticulum (ER) stress and Ca(2+) homeostasis, and also explore the underlying mechanism of the ER stress and Ca(2+) homeostasis in the Cu-induced change of hepatic lipid metabolism in javelin goby Synechogobius hasta. To this end, four experiments were conducted. In experiment 1, the full-length cDNA sequences of two ER molecular chaperones [glucose-regulated protein 78 (GRP78) and calreticulin (CRT)] and three ER stress sensors [PKR-like ER kinase (PERK), inositol requiring enzyme (IRE)-1α, and activating transcription factor (ATF)-6α] cDNAs were firstly characterized from S.

Fe reduced hepatic lipid deposition in Synechogobius hasta exposed to waterborne Cu.

Recent evidences suggested that Fe influenced Cu metabolism in vertebrates. The present study was conducted to test the hypothesis that Fe could alleviate Cu-induced change of lipid deposition in the fish species. Synechogobius hasta were exposed to 0, 0.

Effect of waterborne zinc exposure on lipid deposition and metabolism in hepatopancreas and muscle of grass carp Ctenopharyngodon idella.

The aim of the present study was to explore the effect of waterborne zinc (control, 0.85, 2.20, 3.

De novo characterization of the liver transcriptome of javelin goby Synechogobius hasta and analysis of its transcriptomic profile following waterborne copper exposure.

Previous studies have investigated the physiological responses to chronic copper (Cu) exposure in the liver of Synechogobius hasta; however, little information is available on the underlying molecular mechanisms. In an effort to better understand the mechanisms of Cu toxicity and to illuminate global gene expression patterns modulated by Cu exposure, we obtained the liver transcriptome information of S. hasta by RNA sequencing (RNA-seq) technology and also investigated the differential expression of genes following waterborne Cu exposure.

JAK and STAT members of yellow catfish Pelteobagrus fulvidraco and their roles in leptin affecting lipid metabolism.

The present study clones and characterizes the full-length cDNA sequences of members in JAK-STAT pathway, explores their mRNA tissue expression and the biological role in leptin influencing lipid metabolism in yellow catfish Pelteobagrus fulvidraco. Full-length cDNA sequences of five JAKs and seven STAT members, including some splicing variants, were obtained from yellow catfish. Compared to mammals, more members of the JAKs and STATs family were found in yellow catfish, which provided evidence that the JAK and STAT family members had arisen by the whole genome duplications during vertebrate evolution.

Endoplasmic reticulum stress and disturbed calcium homeostasis are involved in copper-induced alteration in hepatic lipid metabolism in yellow catfish Pelteobagrus fulvidraco.

The present study was conducted to investigate the effect of Cu exposure on ER stress and Ca(2+) homeostasis, and explore the underlying mechanism of the ER stress and disturbed Ca(2+) homeostasis in the regulation of hepatic lipid metabolism in yellow catfish Pelteobagrus fulvidraco. To this end, three experiments were conducted. In experiment 1, P.

Effect and mechanism of waterborne prolonged Zn exposure influencing hepatic lipid metabolism in javelin goby Synechogobius hasta.

The present study was conducted to determine the effect and mechanism of waterborne Zn exposure influencing hepatic lipid deposition and metabolism in javelin goby Synechogobius hasta. S. hasta were exposed to four waterborne Zn concentrations (Zn 0.

Cloning, mRNA expression and transcriptional regulation of five retinoid X receptor subtypes in yellow catfish Pelteobagrus fulvidraco by insulin.

Retinoid X receptors (RXRs) are members of the nuclear receptor superfamily and mediate development, reproduction, homeostasis and cell differentiation processes in vertebrates. In this study, full-length cDNA sequences of five rxr subtypes from yellow catfish Pelteobagrus fulvidraco were cloned. Their mRNA expression patterns in different tissues and transcriptional regulation by insulin were determined.