Fat Diet-induced Nonalcoholic Fatty Liver Research Articles

Triclosan leads to dysregulation of the metabolic regulator FGF21 exacerbating high fat diet-induced nonalcoholic fatty liver disease.

Triclosan (TCS), employed as an antiseptic and disinfectant, comes into direct contact with humans through a plethora of consumer products and its rising environmental release. We have demonstrated that TCS promotes liver tumorigenesis in mice, yet the biological and molecular mechanisms by which TCS exerts its toxicity, especially in early stages of liver disease, are largely unexplored. When mice were fed a high-fat diet (HFD), we found that fatty liver and dyslipidemia are prominent early signs of liver abnormality induced by TCS. The presumably protective HFD-induced hepatic expression of the metabolic regulator fibroblast growth factor 21 (FGF21) was blunted by TCS. TCS-altered Fgf21 expression aligned with aberrant expression of genes encoding metabolic enzymes manifested as profound systemic metabolic changes that disturb homeostasis of amino acids, fatty acids, and glucose. Using a type 1 diabetic animal model, TCS potentiates and accelerates the development of steatohepatitis and fibrosis, accompanied by increased levels of hepatic lipid droplets and oxidative stress. Analysis of fecal samples revealed that HFD-fed mice exhibited a reduction in fecal species richness, and that TCS further diminished microbial diversity and shifted the bacterial community toward lower Bacteriodetes and higher Firmicutes, resembling changes in microbiota composition in nonalcoholic steatohepatitis (NASH) patients. Using reverse-genetic approaches, we demonstrate that, along with HFD, TCS induces hepatic steatosis and steatohepatitis jointly regulated by the transcription factor ATF4 and the nuclear receptor PPARα, which participate in the transcriptional regulation of the Fgf21 gene. This study provides evidence linking nutritional imbalance and exposure to TCS with the progression of NASH.

Compensative Response Elicited towards Steatosis in High Fat Diet-induced Non-alcoholic Fatty Liver Disease in Rats

Compensative Response Elicited towards Steatosis in High Fat Diet-induced Non-alcoholic Fatty Liver Disease in Rats

Vitexin ameliorates chronic stress plub high fat diet-induced nonalcoholic fatty liver disease by inhibiting inflammation

Evidences showed that chronic stress (CS) can aggravate the situation of nonalcoholic fatty liver disease (NAFLD). Vitexin is one of the major components in hawthorn, which is widely used to reduce blood lipid. This study was aimed to explore the therapeutic effects and potential mechanisms of vitexin on chronic stress mice with high-fat diet (CSHFD). The results showed that 5-week vitexin administration (40 mg/kg, i.g.) could obviously reduce hepatic fat deposition, alleviate lipid metabolism, and inhibit liver inflammation in CSHFD mice. In addition, vitexin significantly reduced hepatic macrophage infiltration, obviously down-regulated the mRNA and protein expressions of hepatic SREBP-1c, FAS, ACC. Moreover, we also found that vitexin treatment could significantly inhibit the expressions of TLR4/NF-κB signaling in CSHFD mice. This results suggested that vitexin could ameliorate chronic stress combined with high-fat diet induced NAFLD, and its mechanisms is closely related to inhibit TLR4/NF-κB signaling and reduce fatty acid synthesis proteins.

Shikonin Attenuates Hepatic Steatosis by Enhancing Beta Oxidation and Energy Expenditure via AMPK Activation.

Shikonin, a natural plant pigment, is known to have anti-obesity activity and to improve insulin sensitivity. This study aimed to examine the effect of shikonin on hepatic steatosis, focusing on the AMP-activated protein kinase (AMPK) and energy expenditure in Hepa 1-6 cells and in high-fat fed mice. Shikonin increased AMPK phosphorylation in a dose- and time-dependent manner, and inhibition of AMPK with compound C inhibited this activation. In an oleic acid-induced steatosis model in hepatocytes, shikonin suppressed oleic acid-induced lipid accumulation, increased AMPK phosphorylation, suppressed the expression of lipogenic genes, and stimulated fatty acid oxidation-related genes. Shikonin administration for four weeks decreased body weight gain and the accumulation of lipid droplets in the liver of high-fat fed mice. Furthermore, shikonin promoted energy expenditure by activating fatty acid oxidation. In addition, shikonin increased the expression of PPARγ coactivator-1α (PGC-1α), carnitine palmitoyltransferase-1 (CPT1) and other mitochondrial function-related genes. These results suggest that shikonin attenuated a high fat diet-induced nonalcoholic fatty liver disease by stimulating fatty acid oxidation and energy expenditure via AMPK activation.

Prolyl endopeptidase gene disruption attenuates high fat diet-induced nonalcoholic fatty liver disease in mice by improving hepatic steatosis and inflammation.

BackgroundProlyl endopeptidase (PREP) is a serine endopeptidase that regulates inflammatory responses. PREP inhibitors can reduce hepatocyte lipid accumulation and may participate in the progression of nonalcoholic fatty liver disease (NAFLD). We investigated whether disruption of PREP regulates hepatic steatosis and inflammation in mice with NAFLD.MethodsWild-type and PREP gene disrupted mice were randomly divided into low-fat diet wild-type (LFD-WT), high-fat diet wild-type (HFD-WT), low-fat diet PREP disruption (LFD-PREPgt), and high-fat diet PREP disruption (HFD-PREPgt) groups. Animals were euthanized at the endpoint of 32 weeks. The NAFLD activity score and number of inflammatory cells were determined by hematoxylin-eosin staining and immunohistochemical staining of liver tissue. The expression levels of inflammation- and lipid metabolism-associated genes in the liver and serum were detected by quantitative reverse transcription PCR, mass spectrometry, or enzyme-linked immunosorbent assay.ResultsThe body weight and epididymal fat tissue index of the HFD-PREPgt mice were significantly decreased compared with that of the HFD-WT mice. Moreover, the NAFLD activity score and liver function were attenuated in the HFD-PREPgt mice. Fat accumulation and the level of expression of mRNAs associated with lipid metabolism and proinflammatory responses were improved in the HFD-PREPgt mice. The number of CD68-positive cells in liver tissue and the serum levels of inflammation-associated factors were significantly decreased in the HFD-PREPgt mice compared with those in the HFD-WT mice. Further mechanistic investigations indicated that the protective effect of PREP disruption on liver inflammation was associated with the suppressed production of matrix metalloproteinases (MMPs) and proline-glycine-proline (PGP) and the inhibition of neutrophil infiltration.ConclusionsLoss of PREP lowers the severity of hepatic steatosis and inflammatory responses in a high-fat diet-induced nonalcoholic steatohepatitis model. PREP inhibition may protect against NAFLD.

DHA Protects Against Hepatic Steatosis by Activating Sirt1 in a High Fat Diet-Induced Nonalcoholic Fatty Liver Disease Mouse Model.

AimDocosahexaenoic acid (DHA; C22; n-3) shows beneficial effects on Non-alcoholic fatty liver disease (NAFLD). Deacetylase Sirtuin1 (Sirt1) was reported to increase energy metabolism and decrease lipogenesis. Here, we investigated whether DHA plays a role in protecting against hepatic steatosis via Sirt1.Main MethodsBoth in vivo and in vitro hepatic steatosis models were used: diet-induced obesity (DIO) model (middle-aged C57BL/6 mice fed a high-fat diet (HFD)) and palmitic acid (PA)-induced lipid accumulation cell model (HepG2 cells).Key FindingsIn DIO mice, treatment with DHA (gavage supplementation) for 8 weeks not only inhibited the lipid accumulation, but also increased fatty acids (FA) oxidation and induced triglyceride export in liver. These changes were accompanied by attenuation of inflammation. Moreover, DHA reversed the HFD-induced reduction of Sirt1 in liver. Interestingly, the beneficial effects of DHA were reversed by lentivirus-mediated Sirt1 knockdown, accompanied with increased expression of markers of lipogenesis, inflammation and reduced FA oxidation. In HepG2 cells, DHA prevented the accumulation of PA-induced lipid droplets, the decrease of FA oxidation and the reduction of Sirt1 level. Inhibition of Sirt1 by sirtinol partially reversed the beneficial effects of DHA on PA-treated cells.SignificanceDHA alleviated hepatic steatosis and reduced inflammation of liver in obese middle-aged mice by mechanisms involving Sirt1 activation.

Sodium fluorocitrate having inhibitory effect on fatty acid uptake ameliorates high fat diet-induced non-alcoholic fatty liver disease in C57BL/6J mice

Non-alcoholic fatty liver disease (NAFLD) is excessive fat build-up in the liver without alcohol consumption and includes hepatic inflammation and damage. Excessive influx of fatty acids to liver from circulation is thought to be a pathogenic cause for the development of NAFLD. Thus, inhibition of fatty acid intake into hepatocyte would be a maneuver for protection from high fat diet (HFD)-induced NAFLD. This study was initiated to determine whether sodium fluorocitrate (SFC) as a fatty acid uptake inhibitor could prevent palmitate-induced lipotoxicity in hepatocytes and protect the mice from HFD-induced NAFLD. SFC significantly inhibited the cellular uptake of palmitate in HepG2 hepatocytes, and thus prevented palmitate-induced fat accumulation and death in these cells. Single treatment with SFC reduced fasting-induced hepatic steatosis in C57BL/6J mice. Concurrent treatment with SFC for 15 weeks in HFD-fed C57BL/6J mice prevented HFD-induced fat accumulation and stress/inflammatory signal activation in the liver. SFC restored HFD-induced increased levels of serum alanine aminotransferase and aspartate aminotransferases as hepatic injury markers in these mice. SFC treatment also improved HFD-induced hepatic insulin resistance, and thus ameliorated HFD-induced hyperglycemia. In conclusion, inhibition of fatty acid mobilization into liver through SFC treatment can be a strategy to protect from HFD-induced NAFLD.

Freeze-dried Si-Ni-San powder can ameliorate high fat diet-induced non-alcoholic fatty liver disease.

BACKGROUNDNon-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease worldwide. However, to date, there is no ideal therapy for this disease.AIMTo study the effects of Si-Ni-San freeze-dried powder on high fat diet-induced NAFLD in mice.METHODSTwenty-four male C57BL/6 mice were randomized into three groups of eight. The control group (CON) was allowed ad libitum access to a normal chow diet. The high fat diet group (FAT) and Si-Ni-San group (SNS) were allowed ad libitum access to a high fat diet. The SNS group was intragastrically administered Si-Ni-San freeze-dried powder (5.0 g/kg) once daily, and the CON and FAT groups were intragastrically administered distilled water. After 12 wk, body weight, liver index, visceral fat index, serum alanine aminotransferase (ALT), portal lipopoly-saccharide (LPS), liver tumor necrosis factor (TNF)-α and liver triglycerides were measured. Intestinal microbiota were analyzed using a 16S r DNA sequencing technique.RESULTSCompared with the FAT group, the SNS group exhibited decreased body weight, liver index, visceral fat index, serum ALT, portal LPS, liver TNF-α and liver triglycerides (P < 0.05). Intestinal microbiota analysis showed that the SNS group had different bacterial composition and function compared with the FAT group. In particular, Oscillospira genus was a bacterial biomarker of SNS group samples.CONCLUSIONThe beneficial effects of Si-Ni-San freeze-dried powder on high fat diet-induced NAFLD in mice may be associated with its anti-inflammatory and changing intestinal microbiota effects.

The hepatic-targeted, resveratrol loaded nanoparticles for relief of high fat diet-induced nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the early stage of many metabolic syndromes. The intervention of NAFLD can prevent its further development into severe metabolic syndromes. Given the inefficiency and side effects of chemical drugs for treating NAFLD, the hepatic-targeted nanocarriers loaded with bioactive compounds may offer a more effective and acceptable strategy for eliminating NAFLD. Here we developed hepatic-targeted oxidized starch-lysozyme (OSL) nanocarriers to specifically deliver resveratrol (Res) to liver tissue in order to maximize its therapeutic efficiency. The hepatic targeting was achieved using covalently conjugated galactose (Gal), which is recognized by the asialoglycoprotein receptors specifically expressed in hepatocytes. In steatotic HepG2 cell model, treatment with hepatic-targeted Gal-OSL/Res nanocarriers enhanced the cellular Res uptake and anti-lipogenesis capabilities, and effectively decreased triglyceride accumulation by modulating AMP-activated protein kinase (AMPK)/silent information regulation 2 homolog 1(SIRT1)/fatty acid synthase (FAS)/sterol regulatory element-binding protein-1c (SREBP1c) signaling pathway. In mice, Gal-OSL increased Res delivery into liver tissues and increased their hepatic effective concentration in liver. Most importantly, Gal-OSL/Res nanocarriers effectively reversed NAFLD and recovered hepatic insulin sensitivity of NAFLD mice to the healthy state. Furthermore, Gal-OSL/Res efficiently ameliorated lipid deposition and insulin resistance by modulating AMPK/SIRT1/FAS/SREBP1c signaling pathway and downregulated insulin receptor substrate-1 (IRS-1) phosphorylation at serine 307 in liver. These findings suggested that the hepatic-targeted Gal-OSL nanocarriers delivering Res could potentially serve as a safe and promising platform for NAFLD and other liver related diseases.

SUN-095 Attenuation of Inflammation by a Novel Small Molecule Prevents High Fat Diet-Induced Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of both metabolic and inflammatory diseases, and it has become pervasive worldwide. Inflammation, including inflammation resulting from free fatty acid (FFA) activation of toll-like receptor (TLR) signaling, has been suggested to be an essential component of the pathophysiology of both insulin resistance and NAFLD. High fat (HF) diets promote an increased uptake and storage of FFAs and triglycerides in hepatocytes, which initiates inflammation and steatosis that induces lipotoxicity and an exacerbation of inflammation. In previous studies, we have established the efficacy of phenylmethimazole, a TLR3/4 inhibitor, to prevent and reverse HF diet-induced NAFLD, inflammation, and insulin resistance. A new library of small molecule compounds, including COB-214, was generated to identify even more potent inhibitors of inflammation. The objectives of this study were to evaluate the efficacy of COB-214 to delay and/or prevent hepatic steatosis, inflammation, and insulin resistance in a HF diet-induced model of NAFLD. C57BL/6J male mice were fed a HF diet (60 % fat, 20% protein, 70% carbohydrate) and divided into 3 groups (N=8 for each group): sham injection (stress control), DMSO (vehicle control), COB-214. Each treatment was administered once daily at a dosage of 1mg/kg for 16 weeks. Histological examination of liver sections from these mice using hematoxylin and eosin (H&E) revealed less hepatic lipid accumulation in mice treated with COB-214 when compared to mice in the sham- and DMSO-treated groups. Transcription of pro-inflammatory cytokines was down-regulated in both liver and mesenteric adipose tissue isolated from COB-214-treated mice when compared to sham- and DMSO-treated mice. Treatment with COB-214 prevented HF diet-induced insulin resistance measured by a 3-hour intraperitoneal glucose tolerance test (IPGTT) and 1.5-hour intraperitoneal insulin tolerance test (IPITT). Future directions include determining the efficacy of COB-214 to reverse HF diet-induced NAFLD, inflammation, and insulin resistance. At the conclusion of this study, we hope to have established the role of a novel class of small molecule inhibitors of inflammation in the treatment and prevention of NAFLD.

Chitooligosaccharide supplementation prevents the development of high fat diet-induced non-alcoholic fatty liver disease (NAFLD) in mice via the inhibition of cluster of differentiation 36 (CD36)

Abstract The effects of (GlcN)2-3 on the development of high fat diet-induced non-alcoholic fatty liver disease in C57BL/6J mice and the potential structural-functional relationship between different singular degrees of polymerization (DPs) COSs and CD36 activity were investigated. (GlcN)2-3 was found to significantly inhibit the levels of triglyceride, low density lipid protein and total cholesterol in the serum and liver, thus reducing hepatic steatosis and, ultimately, altering lipid accumulation. This phenomenon was associated with a decrease in the mRNA and protein expressions of CD36, PXR, DGAT2, LXRα and PPARγ, which subsequently decreased the uptake of FFAs and triglyceride synthesis. Using structural analysis, (GlcN)2-3 blocked the core cavity and inhibited the translocation of FFAs in CD36. Furthermore, the molecular size and steric hindrance effect play crucial roles in the deactivation of CD36. These findings will provide a better understanding of the modulating actions of specific singular-DPs COS in high fat diet-induced hepatic steatosis.

Conophylline inhibits high fat diet-induced non-alcoholic fatty liver disease in mice.

Conophylline (CnP), a vinca alkaloid extracted from the leaves of the tropical plant Tabernaemontana divaricate, attenuates hepatic fibrosis in mice. We have previously shown that CnP inhibits non-alcoholic steatohepatitis (NASH) using a methionine-choline-deficient (MCD) diet-fed mouse model. However, little is known about the CnP mediated inhibition of hepatic steatosis in high-fat diet-induced non-alcoholic fatty liver disease (NAFLD) mouse models. CnP (0.5 and 1 μg/g/body weight) was co-administered along with a high-fat diet to male BALB/c mice. After nine weeks of administering the high-fat diet, hepatic steatosis, triglyceride, and hepatic fat metabolism-related markers were examined. Administration of a high-fat diet for 9 weeks was found to induce hepatic steatosis. CnP dose-dependently attenuated the high-fat diet-induced hepatic steatosis. The diet also attenuated hepatic peroxisome proliferator-activated receptor alpha (PPARA) mRNA levels. PPARA is known to be involved in β-oxidation. CnP upregulated the mRNA levels of hepatic PPARA and its target genes, such as carnitine palmitoyl transferase 1 (CPT1) and CPT2, in a dose-dependent manner in the liver. Furthermore, levels of hepatic β-hydroxybutyrate, which is a type of ketone body, were increased by CnP in a dose-dependent manner. Finally, CnP increased the expression of the autophagosomal marker LC3-II and decreased the expression of p62, which are known to be selectively degraded during autophagy. These results indicate that CnP inhibits hepatic steatosis through the stimulation of β-oxidation and autophagy in the liver. Therefore, CnP might prove to be a suitable therapeutic target for NAFLD.

A novel resveratrol-curcumin hybrid, a19, attenuates high fat diet-induced nonalcoholic fatty liver disease

Both inflammation and fibrosis are essential in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Taking inflammatory cytokines and signaling pathways as vital mediators, the inhibition of inflammation response may be an effective approach for treating NAFLD. a19, a resveratrol-curcumin hybrid, has been confirmed to exhibit a good anti-inflammatory activity by preventing LPS-induced inflammatory response in macrophages. The study aims to evaluate the protective effect of a19 on high fat diet (HFD)-induced NAFLD. In the present study, compound a19 significantly inhibited the HFD-induced lipid accumulation, liver injury, liver inflammation and fibrosis in mouse model. In vitro, a19 obviously suppressed the expression of PA-induced inflammatory cytokines and fibrosis markers mRNA. Meanwhile, the anti-inflammatory effect of a19 was found to be associated with the inhibition of ERK signal pathway. These results indicated that a19 can be potentially used as a protective agent for NAFLD.

Sleeve gastrectomy attenuates high fat diet-induced non-alcoholic fatty liver disease

BackgroundA high-fat diet (HFD) is known to lead to obesity, and contributes to the progression of non-alcoholic fatty liver disease. The objective of this study was to evaluate the effects of sleeve gastrectomy (SG) on the progression of HFD-induced hepatic steatosis.MethodsFifteen 4-week-old, male Wistar rats were randomly assigned into three groups: NC, HFD + SHAM and HFD + SG. Their body weight, glucose-lipid metabolism, inflammation indices, hepatic steatosis and fibroblast growth factor 21 (FGF21) levels were measured.ResultsPostoperatively, body weights in the HFD + SHAM and HFD + SG group rats decreased during the first week. Thereafter, HFD + SG rats regained their body weight. Differences in insulin, homeostasis model assessment of insulin resistance, triglyceride, free fatty acid, tumor necrosis factor-α and monocyte chemotactic protein-1 levels were statistically significant across the three groups (all P < 0.05). Interestingly, FGF21 levels in the HFD + SG group were markedly lower than in the HFD + SHAM group (P = 0.015), however, there were no differences in the NC group. Hematoxylin and eosin staining demonstrated that more vacuoles were present in the HFD + SHAM liver when compared to the HFD + SG liver. Oil-red O staining showed less red dots in the HFD + SG liver.ConclusionsDespite eating, surgical re-routing of the gut may prevent weight accumulation, regulate glucose-lipid metabolism and insulin sensitivity, control a chronic inflammatory state, change the secretion pattern of FGF21 and alleviate the severity of fatty liver.

Salidroside and Curcumin Formula Prevents Liver Injury in Nonalcoholic Fatty Liver Disease in Rats

Introduction and aim. Salidroside and curcumin (SC) formula could alleviate lipid deposition in high fat diet-induced nonalcoholic fatty liver disease (NAFLD). However, the mechanisms are still unknown, and the magnitude of potential therapeutic benefit remains understudied.Material and methods. The rats were treated with high fat diet for 14 weeks to induce NAFLD. The experiment was divided into control, model (NAFLD), SC formula and rosiglitazone groups (n = 7 in each group). Hematoxylin-eosin (H&E) staining was applied to detect liver morphological changes. Biochemical, metabolic indices and inflammation factors in liver tissue and serum were detected. Additionally, the activities of related enzymes were detected by enzyme-linked immunosorbent assay.Results. In the established rat model, typical lipid deposition and liver steatosis were observed. Liver triglyceride, free fatty acids, sera alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, fasting insulin, fasting blood glucose and homeostasis model assessment of insulin resistance were elevated in model group. Liver malondialdehyde was significantly elevated, while superoxide dismutase was significantly decreased in model group, compared with control. Moreover, tumor necrosis factor-α and Interleukin-1 were significantly prod uced in model group, compared with control. As a mechanism, high fat diet decreased tissue AMP-activated protein kinase (AMPK), phosphorylated AMPK, carnitine palmitoyltransferase 1 and increased inacetyl-CoA carboxylase (ACCase), phosphorylated ACCase. Importantly, these abnormal changes caused by high fat diet were reduced by SC formula administration.Conclusion. SC formula could ameliorate the injury caused by high fat diet. The effect was likely mediated via its influence on insulin resistance, lipid peroxidation injury and AMPK signaling pathway.

Salidroside and Curcumin Formula Prevents Liver Injury in Nonalcoholic Fatty Liver Disease in Rats

Introduction and aim. Salidroside and curcumin (SC) formula could alleviate lipid deposition in high fat diet-induced nonalcoholic fatty liver disease (NAFLD). However, the mechanisms are still unknown, and the magnitude of potential therapeutic benefit remains understudied. Material and methods. The rats were treated with high fat diet for 14 weeks to induce NAFLD. The experiment was divided into control, model (NAFLD), SC formula and rosiglitazone groups (n = 7 in each group). Hematoxylin-eosin (H&amp;E) staining was applied to detect liver morphological changes. Biochemical, metabolic indices and inflammation factors in liver tissue and serum were detected. Additionally, the activities of related enzymes were detected by enzyme-linked immunosorbent assay. Results. In the established rat model, typical lipid deposition and liver steatosis were observed. Liver triglyceride, free fatty acids, sera alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, fasting insulin, fasting blood glucose and homeostasis model assessment of insulin resistance were elevated in model group. Liver malondialdehyde was significantly elevated, while superoxide dismutase was significantly decreased in model group, compared with control. Moreover, tumor necrosis factor-α and Interleukin-1 were significantly produced in model group, compared with control. As a mechanism, high fat diet decreased tissue AMP-activated protein kinase (AMPK), phosphorylated AMPK, carnitine palmitoyltransferase 1 and increased inacetyl-CoA carboxylase (ACCase), phosphorylated ACCase. Importantly, these abnormal changes caused by high fat diet were reduced by SC formula administration. Conclusion. SC formula could ameliorate the injury caused by high fat diet. The effect was likely mediated via its influence on insulin resistance, lipid peroxidation injury and AMPK signaling pathway.

Pectin Alleviates High Fat (Lard) Diet-Induced Nonalcoholic Fatty Liver Disease in Mice: Possible Role of Short-Chain Fatty Acids and Gut Microbiota Regulated by Pectin.

Consumption of pectin contributes to changes in the gut microbiota and the metabolism of short-chain fatty acids (SCFAs). We aimed to investigate the effects of and mechanism by which pectin prevented nonalcoholic fatty liver disease (NAFLD) in mice that were fed a high-fat diet containing 30% lard (HF). HF-fed mice that orally ingested pectin for 8 weeks exhibited improvements in lipid metabolism and decreased oxidative stress and inflammation through a mechanism regulated by the mitogen-activated protein kinase pathway. Pectin dose-dependently generated an increase in acetic acid (from 566.4 ± 26.6 to 694.6 ± 35.9 μmol/mL, p < 0.05) and propionic acid (from 474.1 ± 84.3 to 887.0 ± 184.7 μmol/mL, p < 0.05) contents and significantly increased the relative abundance of Bacteroides (from 0.27% to 11.6%), Parabacteroides (from 3.9‰ to 5.3%), Olsenella (from 2.9‰ to 1.3%), and Bifidobacterium (from 0.03% to 1.9%) in the gut of HF-fed mice. Intestinal microbiota and SCFAs may thus contribute to the well-established link between pectin consumption and NAFLD.

Apigetrin attenuates high fat diet-induced intestinal inflammation and nonalcoholic fatty liver disease (NAFLD) process

Apigetrin attenuates high fat diet-induced intestinal inflammation and nonalcoholic fatty liver disease (NAFLD) process

Alpinetin improved high fat diet-induced non-alcoholic fatty liver disease (NAFLD) through improving oxidative stress, inflammatory response and lipid metabolism

The non-alcoholic fatty liver disease (NAFLD) has become a serious medical problem and an increasing threat to public health. It is characterized by the abnormal fat accumulation in liver without excessive alcohol intake. The concurrent NAFLD might up-regulate the risk of chronic kidney disease as well as the mortality rate. Though various drugs have been investigated to attenuate NAFLD, further study is still necessary to find new therapeutic strategy and to reveal the underlying molecular mechanism. In the present study, NAFLD animal models were induced by feeding with high fat (HF) diet for 8 weeks. Alpinetin (ALP) was given to mice for another 8 weeks together with HF. Hepatic and renal function, oxidative stress, inflammatory response and lipid metabolism were calculated. And human liver cells of HL-7702 were cultured with high fructose (5mM) with or without ALP. The findings indicated that ALP down-regulated lipid accumulation in liver tissue samples. The higher inflammatory score induced by HF in liver and renal were reduced by ALP. HF-triggered oxidative stress was inhibited in ALP-treated groups, as evidenced by enhanced SOD1/HO-1/Nrf-2 expressions and reduced thioredoxin-interacting protein (TXNIP)/xanthine oxidase (XO) levels. ALP also suppressed inflammatory response by decreasing pro-inflammatory cytokines through inactivating toll-like receptor 4-nuclear factor kappa B (TLR4-NF-κB) pathway. The anti-oxidant and anti-inflammatory effects of ALP were confirmed in HL-7702 cells. Further, abnormal lipid metabolism caused by HF was alleviated by ALP, which was associated with the decreased Stearoyl-CoA desaturase 1 (SCD1), fatty acid synthase (FAS), sterol element regulatory binding protein 1c (SREBP-1c), Liver X Receptor (LXR)-α, elongases of very long-chain fatty acids (Elovl)-2, p-insulin receptor substrate 1 (IRS1) expressions, and increased PPARα levels. Taken together, the results above indicated that ALP could suppress oxidative stress, reduce inflammatory response and attenuate lipid metabolism, preventing NAFLD.

TM5441, a plasminogen activator inhibitor-1 inhibitor, protects against high fat diet-induced non-alcoholic fatty liver disease.

Recent evidences showed that elevation of plasminogen activator inhibitor 1 (PAI-1) was responsible in mediating obesity-induced non-alcoholic fatty liver disease (NAFLD) and metabolic disorders. Here, we investigated the effect of TM5441, an oral PAI-1 inhibitor that lacks of bleeding risk, on high-fat diet (HFD)-induced NAFLD. HFD-fed C57BL/6J mice was daily treated with 20 mg/kg TM5441. To examine the preventive effect, 10-week-treatment was started along with initiation of HFD; alternatively, 4-week-treatment was started in mice with glucose intolerance in the interventional strategy. In vivo study showed that early and delayed treatment decreased hepatic steatosis. Particularly, early treatment prevented the progression of hepatic inflammation and fibrosis in HFD mice. Interestingly, both strategies abrogated hepatic insulin resistance and mitochondrial dysfunction, presented by enhanced p-Akt and p-GSK3β, reduced p-JNK signaling, along with p-AMPK and PGC-1α activation. Consistently, TM5441 treatment in the presence of either PAI-1 exposure or TNF-α stimulated-PAI-1 activity showed a restoration of mitochondrial biogenesis related genes expression on HepG2 cells. Thus, improvement of insulin sensitivity and mitochondrial function was imperative to partially explain the therapeutic effects of TM5441, a novel agent targeting HFD-induced NAFLD.