iridoids and Fatty-Liver

Yīn-Chén-Hāo decoction (YCHD) is a traditional Chinese medicine formula composed of capillaris (

Topics: Animals; Anthraquinones; Anti-Inflammatory Agents; Antiviral Agents; Artemisia; Ascites; Chlorogenic Acid; Clinical Trials as Topic; Coumarins; Drugs, Chinese Herbal; Emodin; Fatty Liver; Gardenia; Humans; Iridoids; Liver Diseases; Plant Extracts; Rheum

Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disorder associated with features of metabolic syndrome and oxidative stress. We examined the mechanism by which the combined extracts of

Topics: AMP-Activated Protein Kinases; Animals; Antioxidants; Diet, High-Fat; Disease Models, Animal; Endoplasmic Reticulum Stress; Eucommiaceae; Fatty Liver; Iridoid Glucosides; Iridoids; Lipid Peroxidation; Male; Oxidative Stress; Phytotherapy; Plant Extracts; Rats, Sprague-Dawley; Reactive Oxygen Species

Gardenoside is one of the most important effective extractions of a herb for its hepatoprotective properties. The aim of this study was to address the mechanism of Gardenoside on HepG2 cellular steatosis induced by free fatty acids (FFAs). The model of HepG2 steatosis was duplicated by oleic and palmitic acid at the proportion of 2:1 (FFAs mixture) for 24 h, then lipid toxicity was induced. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) were used to detect cell viability and Oil Red O staining method was used to judge the lipid accumulation respectively. Inflammatory cytokines TNF-α, IL-1β, IL-6 and intracellular NFκB were measured after 24 h. The steatosis was significantly decreased after Gardenoside treatment without cytotoxicity. TNF-α, IL-1β, IL-6 were modulated to HepG2 cells by treatment of Gardenoside. In the meantime, the activation of NFκB was inhibited by Gardenoside. Gardenoside has a protective effect on FFA-induced cellular steatosis in HepG2 cells which indicates that Gardenoside might be a potential therapeutic herb against NASH by suppressed supernatant inflammatory cytokine production and intracellular NFkB activity.

Topics: Cell Survival; Cytokines; Fatty Acids, Nonesterified; Fatty Liver; Hep G2 Cells; Hepatocytes; Humans; Inflammation Mediators; Iridoids; Lipid Metabolism; NF-kappa B; Phosphorylation

Nonalcoholic steatohepatitis (NASH) is characterized by hepatocyte injury and inflammatory cell infiltration, which has been linked to peripheral insulin resistance and increased levels of triglycerides in the liver. The purposes of this study were to establish a mouse model of NASH by feeding mice a 60% high-fat diet (HFD) and to demonstrate the anti-fibrotic effects of oleuropein, which has been shown to have anti-oxidant and anti-inflammatory properties, in this HFD-induced mouse model of NASH. C57BL/6 mice were divided into three groups: a regular diet group (Chow), a HFD group and an oleuropein-supplemented HFD group (OSD), which was fed a 0.05% OSD for 6 months. The effects of oleuropein in this model were evaluated using biochemical, histological and molecular markers. The expression levels of alpha-smooth muscle actin (α-SMA)and collagen type I in the HFD and OSD groups were evaluated using real-time PCR and western blotting. The body weight, biochemical marker levels, nonalcoholic fatty liver disease activity score, homeostasis model of assessment-insulin resistance (HOMA-IR) and leptin levels observed in the HFD group at 9 and 12 months were higher than those observed in the Chow group. The HOMA-IR and leptin levels in the OSD group were decreased compared with the HFD group. In addition, α-SMA and collagen type I expression were decreased by oleuropein treatment. We established a NASH model induced by HFD and demonstrated that this model exhibits the histopathological features of NASH progressing to fibrosis. Our results suggest that oleuropein may be pharmacologically useful in preventing the progression of steatohepatitis and fibrosis and may be a promising agent for the treatment of NASH in humans.

Topics: Actins; Animals; Antihypertensive Agents; Collagen Type I; Diet, High-Fat; Fatty Liver; Fibrosis; Iridoid Glucosides; Iridoids; Leptin; Liver; Mice; Mice, Inbred C57BL

Insulin resistance (IR) increases with age and plays a key role in the pathogenesis of type 2 diabetes mellitus. Oxidative stress and mitochondrial dysfunction are supposed to be major factors leading to age-related IR. Genipin, an extract from Gardenia jasminoides Ellis fruit, has been reported to stimulate insulin secretion in pancreatic islet cells by regulating mitochondrial function. In this study, we first investigated the effects of genipin on insulin sensitivity and the potential mitochondrial mechanisms in the liver of aging rats. The rats were randomly assigned to receive intraperitoneal injections of either 25mg/kg genipin or vehicle once daily for 12days. The aging rats showed hyperinsulinemia and hyperlipidemia, and insulin resistance as examined by the decreased glucose decay constant rate during insulin tolerance test (kITT). The hepatic tissues showed steatosis and reduced glycogen content. Hepatic malondialdehyde level and mitochondrial reactive oxygen species (ROS) were higher, and levels of mitochondrial membrane potential (MMP) and ATP were lower as compared with the normal control rats. Administration of genipin ameliorated systemic and hepatic insulin resistance, alleviated hyperinsulinemia, hyperglyceridemia and hepatic steatosis, relieved hepatic oxidative stress and mitochondrial dysfunction in aging rats. Furthermore, genipin not only improved insulin sensitivity by promoting insulin-stimulated glucose consumption and glycogen synthesis, inhibited cellular ROS overproduction and alleviated the reduction of levels of MMP and ATP, but also reversed oxidative stress-associated JNK hyperactivation and reduced Akt phosphorylation in palmitate-treated L02 hepatocytes. In conclusion, genipin ameliorates age-related insulin resistance through inhibiting hepatic oxidative stress and mitochondrial dysfunction.

Topics: Adenosine Triphosphate; Age Factors; Aging; Animals; Antioxidants; Cell Line; Dose-Response Relationship, Drug; Enzyme Activation; Fatty Liver; Hepatocytes; Hyperinsulinism; Hyperlipidemias; Hypoglycemic Agents; Insulin Resistance; Iridoids; JNK Mitogen-Activated Protein Kinases; Liver; Male; Malondialdehyde; Membrane Potential, Mitochondrial; Mitochondria, Liver; Oxidative Stress; Palmitic Acid; Phosphorylation; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species

Oleuropein, a bitter glucoside found in green olive leaves, and its metabolite hydroxytyrosol display powerful antioxidant activity both in vivo and in vitro. In this study, we hypothesized that the antioxidant activity of oleuropein could attenuate hepatic steatosis. To test this hypothesis, we established steatotic hepatocytes using HepG2 and FL83B cells treated with free fatty acids (FFAs) (oleate:palmitate, 2:1). To confirm hepatic steatosis, the intracellular lipid levels were quantitatively measured by Nile Red staining, and the sizes and distributions of lipid droplets were visualized by transmission electron microscopy. The expression of PAT family proteins as well as of adipose differentiation-related protein and tail interacting protein (TIP47) was evaluated by reverse transcriptase polymerase chain reaction and immunoblotting. To examine the cellular and molecular events associated with oleuropein, annexin V/propidium iodide staining and immunoblotting were performed. Oleuropein decreased the number and size of lipid droplets in FFA-treated cells and reduced intracellular triglyceride accumulation. However, it did not affect the expression of lipid droplets-associated PAT family proteins, including adipose differentiation-related protein and TIP47. In addition, oleuropein reduced FFA-induced extracellular signal-regulated kinase activation but had no effect on c-Jun N-terminal kinase or AKT activation. Given its protective effects against FFA-induced hepatocellular steatosis, oleuropein may be a lipid-lowering agent.

Topics: Acyltransferases; Adipogenesis; Extracellular Signal-Regulated MAP Kinases; Fatty Acids, Nonesterified; Fatty Liver; Hep G2 Cells; Hepatocytes; Humans; Hypolipidemic Agents; Iridoid Glucosides; Iridoids; JNK Mitogen-Activated Protein Kinases; Membrane Proteins; Olea; Perilipin-2; Perilipin-3; Phytotherapy; Plant Extracts; Plant Leaves; Proto-Oncogene Proteins c-akt; Pyrans; Reverse Transcriptase Polymerase Chain Reaction; Staining and Labeling; Triglycerides; Vesicular Transport Proteins

Uncoupling protein 2 (UCP2) was reported to be involved in lipid metabolism through regulating the production of superoxide anion. However, the role of UCP2 in hepatocytes steatosis has not been determined. We hypothesized that UCP2 might regulate hepatic steatosis via suppressing oxidative stress.. We tested this hypothesis in an in vitro model of hepatocytic steatosis in HepG2 cell lines induced by palmitic acid (PA). We found that treatment with PA induced an obvious lipid accumulation in HepG2 cells and a significant increase in intracellular triglyceride content. Moreover, the specific inhibition of UCP2 by genipin remarkably exacerbated PA-induced hepatocytes steatosis. Interestingly, the PA-induced superoxide overproduction can also be enhanced by incubation with genipin. In addition, administration with the antioxidant tempol abolished genipin-induced increase in intracellular lipid deposition. We further found that genipin significantly increased the protein expression of fatty acid translocase (FAT)/CD36.. These findings suggest that UCP2 plays a protective role in PA-induced hepatocytic steatosis through ameliorating oxidative stress.

Topics: CD36 Antigens; Fatty Liver; Hep G2 Cells; Humans; Ion Channels; Iridoids; Lipid Metabolism; Mitochondrial Proteins; Models, Biological; Oxidative Stress; Palmitic Acid; Triglycerides; Uncoupling Protein 2

Oleuropein, a secoiridoid derived from olives and olive oil, has been known to possess antimicrobial, antioxidative, and anticancer activities. The purpose of the present study was to determine whether oleuropein has a protective effect against hepatic steatosis induced by a high fat diet (HFD) and to elucidate its underlying molecular mechanisms in mice.. Male C57BL/6N mice were fed a normal diet (ND), HFD, or an oleuropein-supplemented diet (OSD) for 10 weeks. The plasma and hepatic lipid levels were determined, and the hepatic gene and protein expression levels were analysed via RT-PCR and Western blotting, respectively.. The supplementation of HFD with oleuropein reversed the HFD-induced increases in liver weight along with plasma and hepatic lipid levels in mice. The expression of Wnt10b inhibitor genes, such as secreted firizzed-related sequence protein 5 and dickkopf homolog 2, was downregulated, whereas the β-catenin protein expression was upregulated in the liver of OSD-fed mice compared to HFD-fed mice. Fibroblast growth factor receptor 1 (FGFR1), phosphoextracellular-signal-regulated kinase 1/2, cyclin D, and E2F transcription factor 1, along with several key transcription factors and their target genes involved in adipogenesis, were downregulated by oleuropein. OSD-fed mice exhibited decreased expression of the toll-like-receptor-(TLR)-mediated signaling molecules (TLR2, TLR4, and myeloid differentiation primary-response gene 88) and proinflammatory cytokines, in their livers, as compared to HFD mice.. These results suggest that the protective effects of oleuropein against HFD-induced hepatic steatosis in mice appear to be associated with the Wnt10b- and FGFR1-mediated signaling cascades involved in hepatic lipogenesis, along with the TLR2- and TLR4-mediated signaling implicated in hepatic steatosis.

Topics: Animals; Antioxidants; beta Catenin; Body Weight; Dietary Fats; Disease Models, Animal; Extracellular Signal-Regulated MAP Kinases; Fatty Liver; Gene Expression; Iridoid Glucosides; Iridoids; Lipogenesis; Liver; Liver Cirrhosis; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Organ Size; Pyrans; Signal Transduction; Toll-Like Receptors

Nonalcoholic steatohepatitis (NASH), a metabolic disorder of the liver, may gradually evolve into fibrosis or cirrhosis. Recent studies have suggested that geniposide can effectively inhibit experimental liver fibrosis. Therefore, the aim of this study was to determine whether geniposide can influence the early phase of fibrogenesis in an animal model of NASH.. Male Sprague-Dawley rats were given a high fat diet alone or the same diet combined with geniposide at doses of 25, 50 or 100 mg/kg for six weeks. Ten rats received corresponding solvent as a normal control.. Treatment with geniposide could improve liver histology through reducing the elevated liver index (liver weight/body weight), serum alanine aminotransferase and aspartate aminotransferase. Total cholesterol, triglycerides and free fatty acids in serum and liver decreased in geniposide-treated rats. Furthermore, geniposide increased serum insulin levels but reduced serum tumour necrosis factor-α level in high-fat diet rats. In addition, geniposide suppressed expression of CYP2E1 and increased peroxisome proliferator-activated receptor-α (PPARα) expression. These benefits may be associated with increased superoxide dismutase and decreased malondialdehyde in liver.. Geniposide exerts protective effects against hepatic steatosis in rats fed with a high fat diet; the underlying mechanism may be associated with its antioxidant actions or regulation of adipocytokine release and expression of PPARα.

Topics: Alanine Transaminase; Animals; Anti-Inflammatory Agents; Aspartate Aminotransferases; Cytochrome P-450 CYP2E1; Dietary Fats; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Fatty Liver; Insulin; Iridoids; Lipid Metabolism; Male; Malondialdehyde; Non-alcoholic Fatty Liver Disease; PPAR alpha; Rats; Rats, Sprague-Dawley; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Accumulation of visceral fat induces various symptoms of metabolic syndrome such as insulin resistance and abnormal glucose/lipid metabolism and eventually leads to the onset of ischemic cerebrovascular diseases. Geniposide, which is iridoid glycoside from the fruit of Gardenia jasminoides ELLIS, is recognized as being useful against hyperlipidemia and fatty liver. In order to clarify the effect of geniposide on metabolic disease-based visceral fat accumulation and the relevant molecular mechanism, experiments were performed in spontaneously obese Type 2 diabetic TSOD mice and the free fatty acid-treated HepG2 cells. In the TSOD mice, geniposide showed suppression of body weight and visceral fat accumulation, alleviation of abnormal lipid metabolism and suppression of intrahepatic lipid accumulation. In addition, geniposide alleviated abnormal glucose tolerance and hyperinsulinemia, suggesting that geniposide has an insulin resistance-alleviating effect. Next, in order to investigate the direct effect of geniposide on the liver, the effect on the free fatty acid-treated HepG2 fatty liver model was investigated using genipin, which is the aglycone portion of geniposide. Genipin suppressed the intracellular lipid accumulation caused by the free fatty acid treatment and also significantly increased the intracellular expression of a fatty acid oxidation-related gene (peroxisomal proliferator-activated receptor: PPARα). From these results, it was confirmed that geniposide has an anti-obesity effect, an insulin resistance-alleviating effect and an abnormal lipid metabolism-alleviating effect, and the metabolite genipin shows a direct effect on the liver, inducing expression of a lipid metabolism-related gene as one of its molecular mechanisms.

Topics: Adipose Tissue; Animals; Anti-Obesity Agents; Body Weight; Diabetes Mellitus, Type 2; Drug Evaluation, Preclinical; Fatty Acids, Nonesterified; Fatty Liver; Gardenia; Glucose Intolerance; Hep G2 Cells; Humans; Hyperinsulinism; Hypoglycemic Agents; Insulin Resistance; Iridoids; Lipid Metabolism; Liver; Male; Metabolic Diseases; Metabolic Syndrome; Mice; Mice, Obese; Obesity; Phytotherapy; Plant Preparations

Oxidative stress may play an important role in the pathogenesis of non-alcoholic steatohepatitis (NASH). Oleuropein, the active constituent of olive leaf, possesses anti-oxidant, hypoglycaemic, and hypolipidaemic activities. We aimed to investigate the preventive effects of olive leaf extract on hepatic fat accumulation in a rat model of NASH.. Spontaneously hypertensive/NIH-corpulent rats were fed a diet of AIN-93G with or without olive leaf extract (500, 1000, 2000 mg/kg diet, and control; 5 rats each) for 23 weeks. Serological and histopathological findings, anti-oxidative activity, and the alteration of fatty acid synthesis in the liver were evaluated.. Histopathologically, a diet of AIN-93G containing more than 1000 mg/kg olive leaf extract had a preventive effect for the occurrence of NASH. Thioredoxin-1 expression in the liver was more evident in rats fed this diet, and 4-hydroxynonenal expression in the liver was less evident in these rats. There were no significant differences in the activities of hepatic carnitine palmitoyltransferase, fatty acid synthase, malic enzyme, and phosphatidic acid phosphohydrolase among the groups.. Our data suggest that olive leaf extract may help prevent NASH, presumably through its anti-oxidative activity.

Topics: Aldehydes; Animal Feed; Animals; Antioxidants; Blood Chemical Analysis; Disease Models, Animal; Fatty Liver; Iridoid Glucosides; Iridoids; Liver; Male; Olea; Organ Size; Oxidative Stress; Plant Leaves; Pyrans; Rats; Rats, Inbred SHR; Thioredoxins

Oleuropein, an active constituent of olive leaf, has a variety of pharmacological activities associated with its capacity to scavenge reactive oxygen species. Oleuropein is also reported to have protective effects against non-alcoholic fatty liver disease (NAFLD) in vivo. In this study, gene expression profiling of hepatic tissues was examined, and transcription factors (TFs) with target genes that were modulated by oleuropein were identified to gain insights into the molecular mechanisms for the hepatoprotective action of this compound. C57BL/6N mice were fed either a high-fat diet (HFD) or 0.03% oleuropein-supplemented HFD for 10 weeks, after which their livers were subjected to oligo DNA microarray analysis. The oleuropein with which the HFD was supplemented reduced the hepatic mRNA level of the genes that encoded the key regulators of the hepatic fatty acid uptake and transport. In addition, the oleuropein reduced the expression of a number of hepatic genes involved in the oxidative stress responses and detoxification of lipid peroxidation products and proinflammatory cytokine genes. The (putative) candidate TFs that bound to the promoters of the genes regulated at least threefold (both up and down) by oleuropein were implicated in the lipogenesis, inflammation, insulin resistance, fibrosis, and cell proliferation and differentiation, which implies that the mechanisms that underlie the beneficial effects of oleuropein on NAFLD may be multifactorial.

Topics: Animals; Dietary Fats; Disease Models, Animal; Fatty Liver; Gene Expression Profiling; Gene Expression Regulation; Iridoid Glucosides; Iridoids; Lipid Metabolism; Liver; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Nutrigenomics; Oligonucleotide Array Sequence Analysis; Pyrans; Transcription Factors

This study was aimed to detect the effect of genipin and Vitamin E (VitE) on non-alcoholic fatty liver disease. L02 cells were divided into five groups:control group, palmic acid treated group, VitE treated group, genipin treated group, and a combination group. All treatments were terminated at the end of 72 hours. Pathological changes of L02 cells were observed. Mitochondrial membrane potential changes were detected by flow cytometry. MDA, SOD, ALT, AST, GGT, TG in culture medium and expression of UCP2 mRNA and protein in L02 cells were detected. We also studied the effects of genipin and VitE on UCP2 and other related factors such as NF-kappaB and TNF-alpha on the L02 cell model of non-alcoholic fatty liver disease. In combination group, the degree of adipose degeneration of L02 cells mitigated significantly; mitochondrial membrane potential and the level of SOD activity increased; the level of MDA, ALT, AST, GGT, TG and the expression of UCP2, NF-kappaB,TNF-alpha in L02 cells decreased. The use of genipin in combination with VitE can increase mitochondrial membrane potential and markedly relieve the adipose degeneration of liver cells.

Topics: Cell Line; Drug Synergism; Fatty Liver; Humans; Ion Channels; Iridoid Glycosides; Iridoids; Liver; Membrane Potential, Mitochondrial; Mitochondrial Proteins; NF-kappa B; Non-alcoholic Fatty Liver Disease; Protective Agents; RNA, Messenger; Tumor Necrosis Factor-alpha; Uncoupling Protein 2; Vitamin E