Activation of Autophagy Relieves Linoleic Acid-Induced Inflammation in Large Yellow Croaker (Larimichthys crocea).

High levels of soybean oil (SO) in fish diets enriched with linoleic acid (LA, 18:2n-6) could induce strong inflammation. However, the molecular mechanism underlying LA-induced inflammation in the liver of large yellow croaker (Larimichthys crocea) has not been elucidated. Based on previous research, autophagy has been considered a new pathway to relieve inflammation. Therefore, the present study was performed to investigate the role of autophagy in regulating LA-induced inflammation in the liver of large yellow croaker in vivo and in vitro. The results of the present study showed that activation of autophagy in liver or hepatocytes could significantly reduce the gene expression of proinflammatory factors, such as tumor necrosis factor α (TNFα) and interleukin 1ß (IL1ß). The results of the present study also showed that inhibition of autophagy could upregulate the gene expression of proinflammatory factors and downregulate the gene expression of anti-inflammatory factors in vivo and in vitro. Furthermore, autophagy could alleviate LA-induced inflammatory cytokine gene expression in vivo and in vitro, while inhibition of autophagy obtained the opposite results. In conclusion, our study shows that autophagy could regulate inflammation and alleviate LA-induced inflammation in the liver of large yellow croaker in vivo and in vitro for the first time, which may offer considerable benefits to the aquaculture industry and human health.

Inhibitory effects of nodakenin on inflammation and cell death in lipopolysaccharide-induced liver injury mice.

BACKGROUND: Nodakenin, a coumarin glucoside isolated from the roots of Angelica biserrata, has been reported to have anti-inflammatory, antibacterial, anticancer effects. However, despite these studies, the potential liver protective effects of nodakenin in inflammatory liver injury models have not been reported. METHODS: A mouse model of inflammatory liver injury was induced by injection of lipopolysaccharide (LPS) (15 mg/kg, intraperitoneally (i.p)). Liver tissue AST, ALT, ROS, T-GSH and T-SOD were analyzed by ELISA. The concentrations of TNF-α, IL-6, and IL-1ß in serum of LPS-induced inflammatory liver injury mice were analyzed. The mRNA expression levels of GPx1, catalase, SOD1, SOD2, TNF-α, IL-6, IL-1ß, iNOS and COX-2 were analyzed using real-time PCR. The expressions of MAPK, IRF3, NF-κB, Nrf2, HO-1, caspase-3 and caspase-7 were analyzed using western blotting. Liver tissue was stained with IHC to confirm NF-κB, Nrf-2, HO-1, caspase-3, Bax, and Bcl2. Tunnel analysis was performed to confirm the fragmented nuclear DNA characteristics of apoptosis. RESULTS: The administration of nodakenin (10 and 30 mg/kg) reduced serum aminotransferase levels compared to LPS-induced liver damage and significantly improved the oxidative state of liver tissue and pathological damage. Moreover, inhibited the phosphorylation of transforming growth factor beta (TGF-ß)-activated kinase (TAK)-1 in LPS-induced inflammatory liver injury model, and significantly inhibited the transcriptional of nuclear factor-kappa B (NF-kB) and the secretion of pro-inflammatory mediators. In addition nodakenin pre-treatment also attenuated hepatocyte death by regulating apoptosis-related mitochondrial proteins, such as cysteinyl aspartate specific proteinase 3 (caspase 3), poly (ADP-ribose) polymerase (PARP), B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax). CONCLUSION: Our findings suggest that nodakenin has anti-inflammatory, anti-oxidant and anti-apoptotic activity and may be an adjunctive prevention agent for liver injury.

Physalis peruviana L. Pulp Prevents Liver Inflammation and Insulin Resistance in Skeletal Muscles of Diet-Induced Obese Mice.

A chronic high-fat diet (HFD) produces obesity, leading to pathological consequences in the liver and skeletal muscle. The fat in the liver leads to accumulation of a large number of intrahepatic lipid droplets (LD), which are susceptible to oxidation. Obesity also affects skeletal muscle, increasing LD and producing insulin signaling impairment. Physalis peruviana L. (PP) (Solanaceae) is rich in peruvioses and has high antioxidant activity. We assessed the ability of PP to enhance insulin-dependent glucose uptake in skeletal muscle and the capacity to prevent both inflammation and lipoperoxidation in the liver of diet-induced obese mice. Male C57BL/6J mice were divided into groups and fed for eight weeks: control diet (C; 10% fat, 20% protein, 70% carbohydrates); C + PP (300 mg/kg/day); HFD (60% fat, 20% protein, 20% carbohydrates); and HFD + PP. Results suggest that PP reduces the intracellular lipoperoxidation level and the size of LD in both isolated hepatocytes and skeletal muscle fibers. PP also promotes insulin-dependent skeletal muscle glucose uptake. In conclusion, daily consumption of 300 mg/kg of fresh pulp of PP could be a novel strategy to prevent the hepatic lipoperoxidation and insulin resistance induced by obesity.

The Inhibitory Effects of Purple Sweet Potato Color on Hepatic Inflammation Is Associated with Restoration of NAD⁺ Levels and Attenuation of NLRP3 Inflammasome Activation in High-Fat-Diet-Treated Mice.

Purple sweet potato color (PSPC), a class of naturally occurring anthocyanins, exhibits beneficial effects on metabolic syndrome. Sustained inflammation plays a crucial role in the pathogenesis of metabolic syndrome. Here we explored the effects of PSPC on high-fat diet (HFD)-induced hepatic inflammation and the mechanisms underlying these effects. Mice were divided into four groups: Control group, HFD group, HFD + PSPC group, and PSPC group. PSPC was administered by daily oral gavage at doses of 700 mg/kg/day for 20 weeks. Nicotinamide riboside (NR) was used to increase NAD⁺ levels. Our results showed that PSPC effectively ameliorated obesity and liver injuries in HFD-fed mice. Moreover, PSPC notably blocked hepatic oxidative stress in HFD-treated mice. Furthermore, PSPC dramatically restored NAD⁺ level to abate endoplasmic reticulum stress (ER stress) in HFD-treated mouse livers, which was confirmed by NR treatment. Consequently, PSPC remarkably suppressed the nuclear factor-κB (NF-κB) p65 nuclear translocation and nucleotide oligomerization domain protein1/2 (NOD1/2) signaling in HFD-treated mouse livers. Thereby, PSPC markedly diminished the NLR family, pyrin domain containing 3 (NLRP3) inflammasome activation, ultimately lowering the expressions of inflammation-related genes in HFD-treated mouse livers. In summary, PSPC protected against HFD-induced hepatic inflammation by boosting NAD⁺ level to inhibit NLRP3 inflammasome activation.

Juglone prevents metabolic endotoxemia-induced hepatitis and neuroinflammation via suppressing TLR4/NF-κB signaling pathway in high-fat diet rats.

Juglone as a natural production mainly extracted from green walnut husks of Juglans mandshurica has been defined as the functional composition among a series of compounds. It showed powerful protective effect in various diseases by inhibiting inflammation and tumor cells growth. However, studies on its anti-inflammatory effect based on high-fat diet-induced hepatitis and neuroinflammation are still not available. In this regard, we first investigated whether juglone suppresses high-fat diet-stimulated liver injury, hypothalamus inflammation and underlying mechanisms by which they may recover them. SD rats were orally treated with or without high-fat diet, 0.25 mg/kg or 1 mg/kg juglone for 70 days. Subsequently, blood, hypothalamus and liver tissue were collected for different analysis. Also, the primary astrocytes were isolated and used to analyze the inhibitory effect of juglone in vitro. Analysis of inflammatory cytokines declared that the inhibition of TNF-α, IL-1ß and IL-6 could be carried by juglone in response to high-fat diet rats. Meanwhile, TLR4 expression and NF-kappa activity also have been confirmed to be the key link in the development of hepatitis and nerve inflammation. The activation was significantly suppressed in treatment group as compared with model. These results indicated that juglone prevents high-fat diet-induced liver injury and nerve inflammation in mice through inhibition of inflammatory cytokine secretion, NF-kappa B activation and endotoxin production.

[The ultrastructural organization of the liver of rats with experimental hepatitis after drinking mineral water containing humic acids].

We undertook the ultrastructural analysis of liver parenchyma taken from male rats with experimental hepatitis induced by the administration of paracetamol at a dose of 1000 mg per 1 kg body weight either following a course of drinking mineral water containing humic acids at a concentration of 20 mg/sq. decimeter) or 14 days after the termination of the drug action (the after-effect phase). It was shown that the consumption of mineral water during 21 days resulted in the modification of the ultrastructural organization of hepatocytes apparent as the increased amount of cisterns in the granulosa endoplasmic system, glycogen rosettes, and mitochondrial polymorphism. These changes give evidence of the restoration of the energy, glycogen and protein synthesizing functions disturbed by paracetamol administration. The after-effect phase was characterized by the further strengthening of reparative processes and the functional activity of hepatic cells.

Effects of intrauterine growth retardation and postnatal high-fat diet on hepatic inflammatory response in pigs.

The objective of this study was to investigate the glucose and insulin response of pigs with intrauterine growth retardation (IUGR) to a high-fat (HF) feeding regimen and to observe the underlying toll-like receptor-4 (TLR4) signalling pathway. Weaned piglets with IUGR or normal birthweight (NBW) (n = 20 each) received during the whole fattening period control diets (0% lard) or HF diets (HF, 10% lard). At about 110 kg body weight, pigs were euthanised to collect hepatic samples. Compared with NBW pigs, IUGR pigs had lower daily gain and feed intake. Growth rate of pigs was increased by HF feeding. Pigs fed HF diets had lower peak concentrations of glucose and insulin, which decreased more slowly than in pigs that received the control diets. The mRNA expression abundances of peroxisome proliferator-activated receptor coactivator-1α (PGC-1α), TLR4, myeloid differentiation factor 88 (MyD88), tumour necrosis factor-α (TNF-α), interleukin 6 (IL-6) and IL-1 receptor antagonist (IL-1Rn) were significantly affected by HF feeding, and IL-6 and IL-1Rn mRNA expressions were up-regulated in IUGR pigs compared with NBW pigs. Western blot analysis indicated that HF feeding elevated the protein expressions of TLR4 signalling pathway, as TLR4, MyD88, IκB kinase ß and nuclear factor-κB, and insulin signalling-related proteins, as phosphorylated insulin receptor substrate-1 and phosphorylated protein kinase B. In summary, hepatic TLR4 signalling pathway and inflammatory response induced by HF feeding played an important role in the aggravated development of insulin resistance in pigs.

[Hepatoprotective effect of thiophane in rats with experimental carbon tetrachloride-induced hepatitis].

A hepatoprotective effect of thiophan was studied on the model of carbon tetrachloride-induced hepatitis in rats. Therapeutic administration of thiophan repairs the antitoxic function of liver, normalizes cytolysis marker activity, and improves the synthetic function of liver and the carbohydrate and lipid metabolism. The hepatoprotective activity of thiophan is similar to effect of silimarin.

[Ultrastructure and TUNEL staining on inhibition of Rubus alceaefolius total alkaloids for apoptosis of liver in rat models of acute hepatitis].

OBJECTIVE: To investigate the anti-apoptosis effects of Rubus alceaefolius total alkaloids in rats with hepatic injury. METHOD: The hepatic injury model of rat was induced by intraperitoneal injection with CCl4. Sixty SD rats were randomly divided into the normal group, the model group, the R. alceaefolius total alkaloids intervened group, and the bifendate intervened group. The expressions of the levels of liver cell apoptosis were determined by TUNEL. Ultrastructures of the liver cells were observed with transmission electron microscope. RESULT: Compared with the model group, the degree of hepatic injury and the positive expressions of apoptosis in liver tissues in the R. alceaefolius total alkaloids intervened groups and the bifendate intervened group were significantly lower. CONCLUSION: R. alceaefolius total alkaloids could reduce the pathological changes and degree of hepatic injury in rats, which may be partially through inhibiting the expressions of apoptosis in liver tissue.

[Hepatoprotective effect of Gossipium hirsutum extract on acute experimental hepatitis on rat liver injury].

OBJECTIVE: To investigate the protective effect on the mice acute experimental hepatic injury by Flos Gossypium herbaceum extracts (FGF-I, FGF-II). METHOD: Experimental hepatic injury model was established by a single intraperitoneal injection of 350 mg x kg(-1) D-CalN in Wistar rats. Serum samples for alanine aminotransferase (ALT), aspartate transferase (AST) level and liver homogenate samples for super oxide dismutase (SOD), malondialdehyde (MDA), Glutathione peroxidese (GSH-PX) activities were assayed. RESULT: For acute experimental hepatic injury, FGF-I and FGF-II significantly decrease the serum transaminase activities (P < 0.01). FGF-I increased the SOD activities (P < 0.01), and decreased MDA content only for 50 mg x kg(-1) FGF-I (P < 0.05), no effect on GSH-PX activity was found for them. FGF-II increased the SOD and GSH-PX activity (P < 0.05) with decreased MDA content (P < 0.05). CONCLUSION: FGF-I and FGF-II showed significant protective action in mice experimental hepatic injury.

Melatonin-selenium nanoparticles inhibit oxidative stress and protect against hepatic injury induced by Bacillus Calmette-Guérin/lipopolysaccharide in mice.

Melatonin-selenium nanoparticles (MT-Se), a novel complex, were synthesized by preparing selenium nanoparticles in melatonin medium. The present investigation was designed to determine the protective effects of MT-Se against Bacillus Calmette-Guérin (BCG)/lipopolysaccharide (LPS)-induced hepatic injury in mice. In BCG/LPS-induced hepatic injury model, MT-Se administered (i.g.) at doses of 5, 10, or 20 mg/kg to BCG/LPS-treated mice for 10 days, significantly reduced the increase in plasma aminotransferase, reduced the severe extent of hepatic cell damage and the immigration of inflammatory cells. The MT-Se particles also attenuated the increase in the content of thiobarbituric acid-reactive substances and enhanced the decrease in reduced activities of superoxide dismutase and glutathione peroxidase (GPx). However, treatment with MT-Se suppressed the increase in nitric oxide levels both in plasma and liver tissue. Furthermore, supplementation with MT-Se at the dose of 10 mg/kg (composed of 9.9 mg/kg melatonin and 0.1 mg/kg selenium) had great capability to protect against hepatocellular damage than a similar dose of melatonin (10 mg/kg) or selenium (0.1 mg/kg) alone. This effect may relate to its higher antioxidant efficacy in decreasing lipid peroxidation and increasing GPx activity. These results suggest that the mode of MT-Se hepatic protective action is, at least in part, related to its antioxidant properties.

Hepatoprotective activity of Leucas hirta against CCl4 induced hepatic damage in rats.

Methanol and aqueous leaf extracts of L. hirta demonstrated hepatoprotective activity against carbon tetrachloride induced liver damage in rats. The parameters studied were serum total bilirubin, total protein, alanine transaminase, aspartate transaminase and alkaline phosphatase activities. The hepatoprotective activity was also supported by histopathological studies of liver tissue. Results of the biochemical studies of blood samples of CCl4 treated animals showed significant increase in the levels of serum markers and decrease in total protein level reflecting the liver injury caused by CCl4. Whereas blood samples from the animals treated with methanol and aqueous leaf extracts showed significant decrease in the levels of serum markers and increase in total protein indicating the protection of hepatic cells. The results revealed that methanol leaf extract followed by aqueous extract of L. hirta could afford significant protection against CCl4 induced hepatocellular injury.

Efficacy of zinc supplementation in preventing acute hepatitis in Long-Evans Cinnamon rats.

OBJECTIVES: Long-Evans Cinnamon (LEC) rats are characterized by an abnormal hepatic deposition of copper (Cu) due to a lack of the Cu-transporter P-type adenosine triphosphatase: accordingly, the strain is a good animal model of Wilson's disease. The effect of oral zinc (Zn) acetate treatment on the development of acute hepatitis and the biochemical parameters of Cu-induced liver damage was studied in 5-week-old LEC rats (n=52). METHODS: Rats receiving 50 or 80 mg/ml/day Zn acetate by gavage and control rats receiving a daily dose of glucose solution 0.02 g/ml by gastric intubation were killed at 1, 2 or 8 weeks after the start of treatment. RESULTS: Treatment with Zn acetate resulted in the prevention of acute hepatitis: 10 of the 13 untreated rats developed signs and symptoms compatible with acute hepatitis between the 6th and 7th week of treatment. Tissue metallothionein (MT) significantly increased in the treated rats and positively correlated with Zn concentrations within the liver. Control rats had a significantly higher iron concentration in the liver and kidneys compared with supplemented rats, after both short- and long-term experiments. 8-hydroxy-2'-deoxyguanosine amounts were significantly lower in untreated rats. CONCLUSIONS: Zn acetate prevents acute hepatitis, by increasing tissue MT concentrations, reducing Cu absorption and interfering with Fe metabolism.

Effect of diphenyl dimethyl bicarboxylate on concanavalin A-induced liver injury in mice.

Diphenyl dimethyl bicarboxylate (DDB) is a hepatoprotectant and used in the treatment of chronic viral hepatitis patients in China. The aim of the present paper was to investigate the effect of DDB on liver injury mediated by immune response in concanavalin A (Con A)-treated mice. A dose of Con A 30 mg/kg was injected via the tailvein to induce liver injury in mice. Serum alanine transaminase (ALT), aspartate aminotransferase (AST), total bile acid (TBA), total bilirubin (TBIL) and tumor necrosis factor alpha (TNF-alpha) level as well as liver TNF-alpha mRNA expression were determined. The following results were obtained: (1) Prior oral administration of DDB 150 mg/kg markedly reduced the elevated serum ALT, TBA and TBIL levels, and the liver lesions in Con A-treated mice; (2) DDB significantly inhibited the elevation of serum TNF-alpha and liver TNF-alpha mRNA expression 2 h after Con A injection; (3) DDB significantly inhibited hepatocyte nuclear DNA fragmentation 12 h after Con A injection; (4) DDB dose-dependently prevented the direct DNA damage induced by CuSO(4)-Phen-Vit C-H(2)O(2) system in vitro, and the ex vivo experiment also showed that the administration of DDB reduced the susceptibility of mouse liver nuclei DNA to CuSO(4)-Phen-Vit C-H(2)O(2) system. These results suggest that DDB could directly protect hepatocyte DNA from oxidative damage, and inhibit TNF-alpha mRNA expression in liver tissue, which resulted in prevention of liver damage induced by Con A in mice.

Tetrathiomolybdate in the treatment of acute hepatitis in an animal model for Wilson disease.

BACKGROUND/AIMS: Tetrathiomolybdate (TTM) is a potent copper-chelating agent that has been shown to be effective in Wilson disease patients with neurological symptoms. Here, we investigate the potential use of TTM in treating the acute hepatic copper toxicosis in Long-Evans Cinnamon (LEC) rats, an authentic model for Wilson disease. METHODS: After the onset of acute hepatitis, LEC rats were treated once with 10 mg TTM/kg. After 1 and 4 days, parameters of liver toxicity and the subcellular distribution and binding of copper and iron were studied. RESULTS: In 11 out of 12 rats TTM rapidly improved acute hepatitis. Hepatic copper decreased through removal from cytosolic metallothionein and lysosomal metallothionein polymers. The remaining lysosomal copper forms a metallothionein-copper-TTM complex. In an almost moribund rat, however, TTM caused severe hepatotoxicity with fatal outcome. CONCLUSIONS: TTM is effective in treating acute hepatitis in LEC rats when applied before the animals become moribund. TTM appears to act by removing the presumable reactive copper associated to lysosomal metallothionein polymers. The remaining lysosomal copper seems to be inactivated by forming a complex with TTM. Moreover, TTM removes copper from cytosolic copper-containing metallothionein. As a consequence, metallothionein is degraded and the uptake of copper-metallothionein into the lysosomes and the formation of the metallothionein polymer associated copper is reduced.

Hepatoprotective activity of andrographolide against galactosamine & paracetamol intoxication in rats.

Hepatoprotective effect of andrographolide (the major active diterpenoid lactone of the plant Andrographis paniculata) was studied on acute hepatitis induced in rats by single dose of galactosamine (800 mg/kg, ip)/paracetamol (3g/kg, po). Hepatoprotective activity was monitored by estimating the serum transaminases (GOT and GPT), alkaline phosphatase and bilirubin in serum, hepatic triglycerides, and by histopathological changes in the livers of experimental rats. Pre-treatment and/or post-treatment of rats at different time intervals with different doses of andrographolide in the two experimental models of hepatotoxicity showed that treatment of rats with 400 mg/kg, ip or 800 mg/kg, po, 48, 24 and 2 h before galactosamine administration or with 200 mg/kg, ip, 1, 4 and 7 h after paracetamol challenge leads to complete normalisation of toxin-induced increase in the levels of all the five biochemical parameters, and significantly ameliorates toxin-induced histopathological changes in the livers of experimental rats. The results confirmed the in vivo hepatoprotective effect of andrographolide against galactosamine or paracetamol-induced hepatotoxicity in rats. Since the protective effect of andrographolide was observed in two types of intoxication, which are very different in their primary mechanism of inducing hepatotoxicity, it is suggested that protective mechanisms of andrographolide which are not specific to galactosamine or paracetamol toxicity may be responsible for the hepatoprotective activity of the compound.