Fold In Liver Research Articles

Immunogenicity of inactivated formalin-killed Photobacterium damselae subsp. piscicida combined with Toll-like receptor 9 agonist in Cobia Rachycentron canadum

The immune responses and protection efficacy of a vaccine containing inactivated formalin-killed Photobacterium damselae subsp. piscicida formulated with alum and different unmethylated Cytosine phosphorothioate Guanine oligodeoxynucleotides (CpG-ODN, including 2006, 2395, 1668, and control ODN 2137) as the adjuvant were investigated in cobia Rachycentron canadum. Results showed that, formulation with CpG-ODN 1668 significantly (P < .05) increased the expression of rctlr9a (11 and 20 fold in spleen and liver, respectively) and il-1β (4 fold in liver) in immunized fish. The highest lysozyme and peroxidase activities were also observed in fish immunized with CpG-ODN 1668 formulation. In addition, compared to other treatments, bactericidal activity using the bacterial survival percentage was significantly less in CpG-ODN 1668 formulation (25%). The antibody titer was significantly higher at 6 and 21 dpi from CpG-ODN 1668 (OD = 0.27 ± 0.02) and CpG-ODN 2006 (OD = 0.24 ± 0.018) formulations. Fish immunized with CpG-ODN 1668 and 2395 formulations protected R. canadum with survival rate of 90 & 70% by P. damselae subsp. piscicida until 3 weeks post-challenge. This study has indicated that different tlr9 agonists have different abilities to augment immune response and protection against Photobacterium. CpG-ODN 1668 can be used as an adjuvant for R. canadum vaccination.

Transcriptome profile analysis reflects rat liver and kidney damage following chronic ultra-low dose Roundup exposure.

BackgroundGlyphosate-based herbicides (GBH) are the major pesticides used worldwide. Converging evidence suggests that GBH, such as Roundup, pose a particular health risk to liver and kidneys although low environmentally relevant doses have not been examined. To address this issue, a 2-year study in rats administering 0.1 ppb Roundup (50 ng/L glyphosate equivalent) via drinking water (giving a daily intake of 4 ng/kg bw/day of glyphosate) was conducted. A marked increased incidence of anatomorphological and blood/urine biochemical changes was indicative of liver and kidney structure and functional pathology. In order to confirm these findings we have conducted a transcriptome microarray analysis of the liver and kidneys from these same animals.ResultsThe expression of 4224 and 4447 transcript clusters (a group of probes corresponding to a known or putative gene) were found to be altered respectively in liver and kidney (p < 0.01, q < 0.08). Changes in gene expression varied from −3.5 to 3.7 fold in liver and from −4.3 to 5.3 in kidneys. Among the 1319 transcript clusters whose expression was altered in both tissues, ontological enrichment in 3 functional categories among 868 genes were found. First, genes involved in mRNA splicing and small nucleolar RNA were mostly upregulated, suggesting disruption of normal spliceosome activity. Electron microscopic analysis of hepatocytes confirmed nucleolar structural disruption. Second, genes controlling chromatin structure (especially histone-lysine N-methyltransferases) were mostly upregulated. Third, genes related to respiratory chain complex I and the tricarboxylic acid cycle were mostly downregulated. Pathway analysis suggests a modulation of the mTOR and phosphatidylinositol signalling pathways. Gene disturbances associated with the chronic administration of ultra-low dose Roundup reflect a liver and kidney lipotoxic condition and increased cellular growth that may be linked with regeneration in response to toxic effects causing damage to tissues. Observed alterations in gene expression were consistent with fibrosis, necrosis, phospholipidosis, mitochondrial membrane dysfunction and ischemia, which correlate with and thus confirm observations of pathology made at an anatomical, histological and biochemical level.ConclusionOur results suggest that chronic exposure to a GBH in an established laboratory animal toxicity model system at an ultra-low, environmental dose can result in liver and kidney damage with potential significant health implications for animal and human populations.Electronic supplementary materialThe online version of this article (doi:10.1186/s12940-015-0056-1) contains supplementary material, which is available to authorized users.

Induction of Antioxidant and Heat Shock Protein Responses During Torpor in the Gray Mouse Lemur, Microcebus murinus

A natural tolerance of various environmental stresses is typically supported by various cytoprotective mechanisms that protect macromolecules and promote extended viability. Among these are antioxidant defenses that help to limit damage from reactive oxygen species and chaperones that help to minimize protein misfolding or unfolding under stress conditions. To understand the molecular mechanisms that act to protect cells during primate torpor, the present study characterizes antioxidant and heat shock protein (HSP) responses in various organs of control (aroused) and torpid gray mouse lemurs, Microcebus murinus. Protein expression of HSP70 and HSP90α was elevated to 1.26 and 1.49 fold, respectively, in brown adipose tissue during torpor as compared with control animals, whereas HSP60 in liver of torpid animals was 1.15 fold of that in control (P<0.05). Among antioxidant enzymes, protein levels of thioredoxin 1 were elevated to 2.19 fold in white adipose tissue during torpor, whereas Cu–Zn superoxide dismutase 1 levels rose to 1.1 fold in skeletal muscle (P<0.05). Additionally, total antioxidant capacity was increased to 1.6 fold in liver during torpor (P<0.05), while remaining unchanged in the five other tissues. Overall, our data suggest that antioxidant and HSP responses are modified in a tissue-specific manner during daily torpor in gray mouse lemurs. Furthermore, our data also show that cytoprotective strategies employed during primate torpor are distinct from the strategies in rodent hibernation as reported in previous studies.

Antioxidant activities of tamarind (Tamarindus Indica) seed coat extracts using in vitro and in vivo models.

Tamarindus indica seed coat was extracted with methanol, acetone and water and screened for DPPH radical scavenging activities. Methanol extract showed higher activity than other extracts. Treatment of albino rats (Wistar strain) with CCl4 at 1.25mL/kg of body weight decreased superoxide dismutase (55%), catalase (73%) and peroxidase (78%), while lipid peroxidation increased nearly 2.5 fold in liver. Pretreatment of rats with methanol extract of T. Indica seed coat (TSCE) at 50mg/kg (as tannic acid equivalents) followed by CCl4 treatment, caused restoration of superoxide dismutase, catalase and lipid peroxidation to values close to control while peroxidase was restored to 67% of the control. Histopathological studies of liver of different groups supported the protective effects of TSCE by restoring the hepatic architecture. These studies could be further extended to exploit its possible application for the preservation of food products as well as a health supplement and neutraceutical.

Environmental Hypertonicity Causes Induction of Gluconeogenesis in the Air-Breathing Singhi Catfish, Heteropneustes fossilis

The air-breathing singhi catfish (Heteropneustes fossilis) is frequently being challenged by different environmental insults such as hyper-ammonia, dehydration and osmotic stresses in their natural habitats throughout the year. The present study investigated the effect of hyperosmotic stress, due to exposure to hypertonic environment (300 mM mannitol) for 14 days, on gluconeogenesis in this catfish. In situ exposure to hypertonic environment led to significant stimulation of gluconeogenic fluxes from the perfused liver after 7 days of exposure, followed by further increase after 14 days in presence of three different potential gluconeogenic substrates (lactate, pyruvate and glutamate). Environmental hypertonicity also caused a significant increase of activities of key gluconeogenic enzymes, namely phosphoenolpyruvate carboxykinase, fructose 1, 6-bisphosphatase and glucose 6-phosphatase by about 2-6 fold in liver, and 3-6 fold in kidney tissues. This was accompanied by more abundance of enzyme proteins by about 1.8–3.7 fold and mRNAs by about 2.2–5.2 fold in both the tissues with a maximum increase after 14 days of exposure. Hence, the increase in activities of key gluconeogenic enzymes under hypertonic stress appeared to be as a result of transcriptional regulation of genes. Immunocytochemical analysis further confirmed the tissue specific localized expression of these enzymes in both the tissues with the possibility of expressing more in the same localized places. The induction of gluconeogenesis during exposure to environmental hypertonicity possibly occurs as a consequence of changes in hydration status/cell volume of different cell types. Thus, these adaptational strategies related to gluconeogenesis that are observed in this catfish under hypertonic stress probably help in maintaining glucose homeostasis and also for a proper energy supply to support metabolic demands mainly for ion transport and other altered metabolic processes under various environmental hypertonic stress-related insults.

Diverse cell-specific expression of myoglobin isoforms in brain, kidney,gill and liver of the hypoxia-tolerant carp and zebrafish

Myoglobin (Mb) is famous as a muscle-specific protein--yet the common carp expresses the gene (cMb1) encoding this protein in a range of non-muscle tissues and also expresses a novel isoform (cMb2) in the brain. Using a homologous antibody and riboprobes, we have established the relative amounts and cellular sites of non-muscle Mb expression in different tissues. The amounts of carp myoglobin (cMb) in supernatants of different tissues were just 0.4-0.7% relative to that of heart supernatants and were upregulated by two-to-four fold in liver, gill and brain following 5 days of hypoxic treatment. Brain exhibited both cMb proteins in western analysis, whereas all other tissues had only cMb1. We have also identified cells expressing cMb protein and cMb mRNA using immunohistology and RNA in situ hybridisation (RNA-ISH), respectively. Mb was strongly expressed throughout all cardiac myocytes and a subset of skeletal muscle fibres, whereas it was restricted to a small range of specific cell types in each of the non-muscle tissues. These include pillar and epithelial cells in secondary gill lamellae, hepatocytes, some neurones, and tubular epithelial cells in the kidney. Capillaries and small blood vessels in all tissues exhibited Mb expression within vascular endothelial cells. The cMb2 riboprobe located expression to a subset of neurones but not to endothelial cells. In zebrafish, which possesses only one Mb gene, a similar expression pattern of Mb protein and mRNA was observed. This establishes a surprisingly cell-specific distribution of Mb within non-muscle tissues in both carp and zebrafish, where it probably plays an important role in the regulation of microvascular, renal and brain function.

Increased systemic and brain cytokine production and neuroinflammation by endotoxin following ethanol treatment

BackgroundCytokines and alcohol share a common modulation of inflammation and hormones as well as being implicated in multiple diseases, but the mechanisms are poorly understood. The purpose of this study was to investigate the interaction of liver, serum and brain cytokines as well as whether ethanol would potentiate endotoxin (Lipopolysaccharide, LPS) responses once ethanol had cleared.MethodsMale C57BL/6J mice were treated intragastrically with water (control) or ethanol (5 g/kg, i.g., 25% ethanol, w/v), with volumes matched, for 1 day or daily for 10 days. Mice were then injected intraperitoneally with saline (control) or LPS (3 mg/kg, i.p.) in saline 24 hrs after the last dose of ethanol. Gene expression and protein synthesis of proinflammatory cytokines and anti-inflammatory cytokine, oxidative enzymes, microglial activation and inhibition of neurogenesis were examined using real-time PCR, ELISA, and immunohistochemistry.ResultsLPS increased proinflammatory cytokines (TNFα, MCP-1, IL-1β) several fold in liver, brain and serum at 1 hr. Ethanol is known to increase liver cytokines and alter the risk of multiple chronic diseases. Ten daily doses of ethanol increased brain and liver TNFα, and pretreatment with ethanol potentiated LPS-induced increases in TNFα, MCP-1, IL-1β in liver, serum and brain. Proinflammatory cytokine levels in liver and serum returned to basal levels within a day, whereas brain proinflammatory cytokines remained elevated for long periods. IL-10, an anti-inflammatory cytokine, is reduced in brain by ethanol and LPS, while brain proinflammatory cytokines remain increased, whereas liver IL-10 is increased when proinflammatory cytokines have returned to control levels. Activation of brain microglia indicated by morphological changes, reduced neurogenesis and increased brain expression of COX-2 and gp91phox NADPH oxidase subunit mRNA were found in the 10 daily doses of ethanol-pretreated LPS group.ConclusionAcute increases in serum cytokines induce long lasting increases in brain proinflammatory cytokines. Ten daily doses of ethanol exposure results in persistent alterations of cytokines and significantly increases the magnitude and duration of central and peripheral proinflammatory cytokines and microglial activation. Ethanol induced differential anti-inflammatory cytokine IL-10 responses in liver and brain could cause long lasting disruption of cytokine cascades that could contribute to protection or increased risk of multiple chronic diseases.

Polynitroxyl Albumin Prevents Vaso-Occlusion in Transgenic Sickle Mice.

Sickle cell disease is characterized by excessive oxidative stress. Sickle patients have enhanced rates of endogenous reactive oxygen species (ROS) production and impaired antioxidant defense mechanisms. We hypothesize that excessive production of ROS promotes activation of vascular endothelium and vaso-occlusion in sickle cell disease. Intravascular ROS production has been shown to trigger the activation of vascular endothelium and increase leukocyte-endothelium interactions. We investigated whether inhibition of intravascular ROS production by treatment with polynitroxyl albumin (PNA), a superoxide dismutase and catalase mimetic agent, could modulate endothelial cell activation and vaso-occlusion in S+S Antilles transgenic sickle mice after hypoxia-reoxygenation. Nuclear factor-kappa B (NF-kB), an oxidant sensitive transcription factor critical for endothelial cell activation, was elevated in lungs and livers of sickle mice and was reduced 2.5 (p=0.043) and 1.5 (p=0.043) fold respectively, by treatment with PNA after hypoxia-reoxygenation. Similarly, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) were elevated 3 to 4.7 fold in the same organs (p<0.05). After treatment with PNA, VCAM-1 expression was reduced 2.3 fold in lungs (p=0.014) and 1.5 fold in livers (p=0.006), ICAM-1 expression decreased 1.7 fold in lungs (p=0.014) and 2 fold in livers (p=0.007). Control studies using human serum albumin had no effect on NF-kB activation or adhesion molecule expression in sickle mice. These anti-inflammatory effects of PNA on endothelium corresponded with changes in blood flow in dorsal skin venules. Intravital microscopy revealed that PNA significantly inhibited hypoxia-reoxygenation-induced leukocyte rolling (3.8 fold inhibition, p<0.001) and completely inhibited vaso-occlusion (p<0.001) in venules in the dorsal skin of transgenic sickle mice. We speculate that therapies that reduce ROS will result in improved organ perfusion in sickle cell disease.

Interactions alcool–xénobiotiques. Rôle du cytochrome P450 2E1

Alcohol and xenobiotics share the same oxidative microsomal pathway, which is mainly located in the endoplasmic reticulum of hepatocytes. This pathway involves enzymes that belong to the super family of cytochrome P450 and allows to explain a lot of pharmacokinetic or toxic interactions between alcohol and xenobiotics. Cytochrome P450 2E1 (CYP2E1) is the key enzyme of the microsomal pathway of ethanol oxidation. It is inducible by chronic ethanol consumption and its activity is increased by three to five fold in liver from alcoholics subjects. This induction involves to a lesser extent cytochromes P450 3A4 and 1A2 and contributes to the metabolic tolerance of alcohol and drugs observed in alcoholics. The metabolic tolerance persits several days after ethanol withdrawal. Furthermore, CYP2E1 has a high capacity to activate numerous xenobiotics into toxic or carcinogenic compounds. Drugs currently used such as paracetamol, anesthetics (enflurane, halothane), industrial solvents (benzene or its derivatives), halogenated solvents (CCl 4, trichlorethylene) and nitrosamines which are present in food or tobacco smoke are included. Therefore, heavy consumption of alcohol, which results in CYP2E1 induction, increases individual susceptibility to the toxic or carcinogenic effects of these xenobiotics.

Coordinate induction of peroxisomal acyl-CoA oxidase and UCP-3 by dietary fish oil: a mechanism for decreased body fat deposition

Rats fed dietary fats rich in 20- and 22-carbon polyenoic fatty acids deposit less fat and expend more energy at rest than rats fed other types of fats. We hypothesized that this decrease in energetic efficiency was the product of: (a) enhanced peroxisomal fatty acid oxidation and/or (b) the up-regulation of genes encoding proteins that were involved with enhanced heat production, i.e. mitochondrial uncoupling proteins (UCP-2, UCP-3) and peroxisomal fatty acid oxidation proteins. Two groups of male Fisher 344 rats 3–4 week old ( n=5 per group) were pair fed for 6 weeks a diet containing 40% of its energy fat derived from either fish oil or corn oil. Epididymal fat pads from rats fed the fish oil diet weighed 25% ( P < 0.05) less than those found in rats fed corn oil. The decrease in fat deposition associated with fish oil ingestion was accompanied by a significant increase in the abundance of skeletal muscle UCP-3 mRNA. The level of UCP-2 mRNA skeletal muscle was unaffected by the type of dietary oil, but the abundance of UCP-2 mRNA in the liver and heart were significantly lower ( P < 0.05) in rats fed fish oil than in rats fed corn oil. In addition to inducing UCP-3 expression, dietary fish oil induced peroxisomal acyl-CoA oxidase gene expression 2–3 fold in liver, skeletal muscle and heart. These data support the hypothesis that dietary fish oil reduces fat deposition by increasing the expression of mitochondrial uncoupling proteins and increasing fatty acid oxidation by the less efficient peroxisomal pathway.

Effect of dietary GABA and protein on growth, food intake and GABA metabolism in the rat

GABA, when present as 4.5% of a 6% casein diet, decreased food intake and almost completely suppressed growth in young rats. Growth and food intake increased as dietary protein content increased; growth of rats receiving a 60% casein diet+GABA was 86% of that in the absence of GABA. Plasma, liver and kidney concentrations of GABA became lower as dietary protein content increased; brain GABA levels were unaltered by dietary GABA. GABA transaminase (GABA-T; E.C. 2.6.1.19) activity per mg tissue protein increased 2–3 fold in liver as dietary protein content increased but activity in brain and kidney did not change. Total hepatic enzyme activity in rats fed 80% casein was about 7 fold greater than in rats fed a protein-free diet. Rats fed 20% or 60% casein converted in 6 hrs about twice as much 14C-GABA to 14CO 2 as did rats fed 6% casein. Urinary excretion of 14C-GABA was not altered by changes in dietary protein content. Relationships between the suppression of food intake and growth by dietary GABA and its neurotransmitter functions are not clear.

Influence of (—)-Hydroxycitrate on Lipogenesis in Chickens and Rats

The influence of (-)-hydroxycitrate on in vitro rates of fatty acid synthesis in chicken and rat liver and in rat adipose tissue was investigated. Following acute and chronic administration of (-)-hydroxycitrate to chickens and rats, changes in rates of fatty acid synthesis in vivo and in lipogenic enzyme activities were also determined. Addition of 1 mM (-)-hydroxycitrate to a buffer containing 10 mM glucose and liver slices from chickens or rats depressed the rate of 3H2O incorporation into fatty acids. Acute administration of (-)-hydroxycitrate to chickens and rats also depressed in vivo rates of fatty acid synthesis in the livers of these species. Chickens appeared to be more sensitive to the inhibitory effects of (-)-hydroxycitrate than did rats. (-)-Hydroxycitrate was incorporated into the diets fed to the chickens and rats. Hepatic citrate cleavage enzyme activities were increased several fold in livers of chickens and rats fed (-)-hydroxycitrate. However, the rates of fatty acid synthesis in chicken and rat livers were depressed when expressed per g liver. Livers of chickens fed (-)-hydroxycitrate for 14 days were enlarged. Dietary (-)-hydroxycitrate did not depress rates of fatty acid synthesis per liver in these birds. Consumption of (-)-hydroxycitrate did not alter liver weight in rats. In vivo rates of fatty acid synthesis in rat adipose tissue were not influenced by consumption of a diet containing 52.6 nmoles (-)-hydroxycitrate/kg diet. Plasma triglyceride levels were increased two-fold in chickens, but unchanged in rats, fed (-)-hydroxycitrate for 2 to 3 weeks. There are species-specific as well as organ-specific responses to (-)-hydroxycitrate.

THE GAMMA‐AMINOBUTYRIC ACID (GABA) SYSTEM IN BRAIN DURING ACUTE AND CHRONIC ETHANOL INTOXICATION

Abstract— The effects of acute and chronic ethanol intoxication on the GAGA system of rats have been investigated. Under the terminal conditions provoked. by ethanol (6–8 g/kg, i.p.) the brain GABA content sharply increased. There was a simultaneous decrease of 35–40% in the glutamate decarboxylase (GAD) activity of the cerebellum and cerebral hemispheres. In contrast, the transaminase, GABA‐T was either unchanged, or it increased: by 28% only in cerebellum and by 1.5–2.0–fold in liver and kidney. It is suggested that effects of acute ethanol intoxication at different doses (2–8 g/kg) on the brain GABA system is connected with the phases of the functional condition of the CNS and a disturbance of homeostatic function. Chronic ethanol consumption caused a decrease in brain GABA. an increase of GAD activity in cerebellum and cerebral hemispheres, and no change in GABA‐T activity. The activity of this last enzyme was increased 1.5–2.0‐fold in liver and kidneys of rats consuming a diet containing 10% ethanol daily. A 50‐fold purified preparation of GABA‐T obtained from pig brain was inhibited by butanol‐l and propanol‐1 (0.03–0.6m) with no effect of ethanol. It is suggested that the mechanisms involved in the ethanol effect on nervous cells are linked with the GABA system and the phases of the functional condition of the CNS.