Fatty Liver Model Research Articles

Auricularia polytricha aqueous extract supplementation decreases hepatic lipid accumulation and improves antioxidative status in animal model of nonalcoholic fatty liver

Auricularia polytricha aqueous extract supplementation decreases hepatic lipid accumulation and improves antioxidative status in animal model of nonalcoholic fatty liver

Exacerbated hepatotoxicity in in vivo and in vitro non-alcoholic fatty liver models by biomineralized copper sulfide nanoparticles

Exacerbated hepatotoxicity in in vivo and in vitro non-alcoholic fatty liver models by biomineralized copper sulfide nanoparticles

Ameliorative Potential of Menstrual Blood-derived Endometrial Stem Cells in Alcohol-Induced Fatty Liver Disease

Background: Alcohol-induced fatty liver disease (AFLD) begins with steatosis and may progress to a range of pathological liver changes, including fibrosis, cirrhosis, and complications. Menstrual blood-derived endometrial stem cells (MenSCs) have shown potential therapeutic effects against various types of liver damage. However, the liver-protective effects of MenSCs in AFLD are not well understood. This study aimed to evaluate the therapeutic effects of MenSCs on AFLD progression. Methods: MenSCs were sourced from women in good health (N=5, 25-34 years old). Male C57BL/6 mice were separated into three distinct groups to establish the mouse models. The AH/- MenSCs group received MenSCs (5×105 cells/mouse) transplantation through tail injection on the 7th and 13th days following the initiation of the alcohol-induced fatty liver model. The therapeutic effects of MenSCs transplantation in AFLD mouse models were subsequently explored using qPCR, Western blotting, histopathological examination, and mRNA sequencing analysis. Results: MenSCs significantly improved liver function and reduced lipid accumulation in AFLD. Treatment with MenSCs was also found to reduce the expression levels of inflammatory cytokines and profibrotic markers in the liver tissues of the mouse model. Additionally, the MenSCs- treated group demonstrated a significant reduction in endoplasmic reticulum (ER) stress and oxidative stress, along with an increase in autophagic activity. Conclusion: The findings provided preliminary evidence of the multifaced protective effects of MenSCs in AFLD.

Caveolin-1 ameliorates hepatic injury in non-alcoholic fatty liver disease by inhibiting ferroptosis via the NOX4/ROS/GPX4 pathway

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease globally, with a complex and contentious pathogenesis. Caveolin-1 (CAV1) is an important regulator of liver function and can mitigate liver injury by scavenging reactive oxygen species (ROS). Evidence suggests that NOX4 is a source of ROS production, that oxidative stress and ferroptosis are closely related, and that both are involved in the onset and progression of NAFLD. However, whether CAV1 attenuates liver injury in NAFLD caused by high-fat diet via the NOX4/ROS/GPX4 pathway remains unclear. An in vivo fatty liver model was established by feeding mice with a high-fat diet for 16 weeks. In addition, an in vitro fatty liver model was established by incubating AML-12 cells with free fatty acids for 24 h using an in vitro culture method. In our study, it was observed that a high-fat diet induces mitochondrial damage and worsens oxidative stress in NAFLD. This diet also hinders GPX4 expression, leading to an escalation of ferroptosis and lipid accumulation. To counteract these effects, intraperitoneal administration of CSD peptide in mice attenuated the high-fat diet-induced liver mitochondrial damage and ferroptosis. Likewise, overexpression of CAV1 resulted in an increase in GPX4 expression and a reduction in levels of ROS-mediated iron metamorphosis, thus mitigating the progression of the disease. However, the effects of CAV1 on GPX4-mediated ferroptosis and lipid deposition could be reversed by CAV1 small interfering RNA (SiRNA). Finally, NOX4 inhibitor (GLX351322) treatment increased CAV1 siRNA-mediated GPX4 expression and decreased the level of ROS-mediated ferroptosis. These findings suggest a potential mechanism underlying the protective role of CAV1 against high-fat diet-induced hepatotoxicity in NAFLD, shedding new light on the interplay between CAV1, GPX4, and ferroptosis in liver pathology

Construction and comparative analysis of an early screening prediction model for fatty liver in elderly patients based on machine learning

Objective: To construct a prediction model for fatty liver disease (FLD) among elderly residents in community using machine learning (ML) algorithms and evaluate its effectiveness. Methods: The physical examination data of 4989 elderly people (aged over 60 years) in a street of Shanghai from 2019 to 2023 were collected. The subjects were divided into a training set and a testing set in a 7:3 ratio. Using feature selection and importance sorting methods, eight indicators were selected, including high-density lipoprotein cholesterol, body mass index, uric acid, triglycerides, albumin, red blood cell, white blood cell, and alanine aminotransferase. Six ML models, including Categorical Features Gradient Boosting, eXtreme Gradient Boosting, Light Gradient Boosting Machine, Random Forest, Decision Tree, and Logistic Regression, were constricted, and their predictive performances were compared via accuracy, precision, recall, F1 score, and Area Under Receiver Operating Characteristic Curve. Results: Among the six ML models, the Categorical Features Gradient Boosting model demonstrated the highest prediction accuracy of 0.74 for FLD in elderly community population, along with a precision of 0.70, a recall of 0.73, a F1 score of 0.71, and an area under the curve of 0.74. Conclusions: In the context of rapid development of artificial intelligence, a community-based elderly FLD prediction model constructed using ML algorithms aid family general practitioners in the early diagnosis, early treatment, and health management of local FLD patients.

A ferrous fluorescence lifetime response probe for monitoring changes in lipid droplets during ferroptosis and imaging in liver disease model

Ferrous ions (Fe2⁺) accumulation and abnormal alterations in lipid droplets (LDs) are closely associated with ferroptosis. In the liver, excessive iron accumulation promotes oxidative stress and exacerbates lipid droplet accumulation, while the disruption of iron homeostasis may also affect the formation and size of lipid droplets, their increased number and size can exacerbate the severity of disease under fatty liver conditions. The leads to hepatocyte damage, further triggering liver inflammation, fibrosis, and ultimately resulting in cirrhosis and hepatocellular carcinoma. Therefore, real-time monitoring of iron ion and lipid droplet changes is crucial for assessing the severity of liver disease, disease progression, and understanding the mechanisms of ferroptosis. We have developed a fluorescent probe, NRFep, for real-time monitoring of iron ion fluctuations and visualization of lipid droplet changes in ferroptosis and liver disease models. NRFep is specific and sensitive to iron ions and exhibits excellent stability in both cells and animal models. In addition, NRFep can be used to monitor changes in iron ions and lipid droplets in mouse liver injury and fatty liver models. Through fluorescence lifetime imaging technology, NRFep can also study the dynamic changes of intracellular iron ion content. NRFep provides a powerful tool for studying ferroptosis and related diseases, and its unique dual-monitoring function opens up new possibilities for developing new diagnostic and therapeutic strategies.

A Nanofluorescent Probe for Evaluating the Fluctuation of Aminopeptidase N in Nonalcoholic Fatty Liver Disease and Hepatic Fibrosis.

Aminopeptidase N (APN/CD13) is a widely expressed transmembrane ectoenzyme that is crucial for maintaining normal physiological activities. It exhibits abnormal activity closely associated with hepatic fibrosis and nonalcoholic fatty liver disease (NAFLD). Therefore, there is a high demand for noninvasive detection of aminopeptidase N (APN) in the diagnosis and research of related diseases. Here, we developed a small molecule fluorescent probe, Hcy-APN, which is a fluorescent probe with high sensitivity and selectivity for the detection of APN. Furthermore, we synthesized the fluorescent nanoprobe Hcy-APN@MSN by self-assembling Hcy-APN and mesoporous silica nanoparticles in solution using a combination of molecular probe design and nanofunctionalization strategies. The detection limit of this probe was 1.5 ng/mL. Hcy-APN@MSN exhibits more stable spectral characteristics compared to Hcy-APN and is suitable for detecting APN activity in live cells and mice. Hcy-APN@MSN was utilized for in vivo and intracellular imaging of NAFLD and hepatic fibrosis at different stages, as well as for a systematic assessment of APN levels in the liver. The results confirm an elevation in the expression levels of APN in NAFLD and hepatic fibrosis models. Furthermore, we investigated the inhibitory effect of the APN inhibitor bestatin in nonalcoholic fatty liver and hepatic fibrosis disease models, confirming its regulatory effect on APN levels in cells and in vivo in both disease models. Therefore, this study may offer diagnostic possibilities for detecting NAFLD and hepatic fibrosis.

The mechanistic study of diacylglycerol in ameliorating non-alcoholic fatty liver and systemic lipid accumulation

The escalating prevalence of non-alcoholic fatty liver disease (NAFLD), driven by inadequate dietary habits and metabolic imbalances, underscores the urgent need for effective dietary interventions. This study investigated the potential of 80 % peanut diacylglycerol (DAG) as a functional lipid component in preventing NAFLD and associated intestinal microenvironment based on a high-cholesterol diet (HCD)-induced zebrafish model. We first found that the zebrafish fatty liver model shared multiple similar pathways like lipid-induced atherosclerosis, insulin resistance with NAFLD patient in terms of lipid metabolism. Employing larvae and grown zebrafish, we aimed to elucidate the preventive and alleviating effect of a DAG diet on NAFLD respectively. Results showed that DAG post-intervention significantly decreased hepatic lipid accumulation and diminished intestinal inflammatory in fatty liver zebrafish model. Notably, transcriptomic sequencing illuminated upregulation in genes related to lipid metabolism (e.g., fasn, mogat2, cd36), suggesting that peanut DAG accelerated lipid transportation and fostered a metabolic environment less conducive to NAFLD symptoms. Besides, reduced liver lipid droplets and hepatic inflammatory suggested DAG feeding could also prevent the formation of NAFLD. The study provided compelling evidence supporting the incorporation of DAG into the diet as a strategy for the prevention and management of fatty liver disease, proposing a novel approach to functional food development aimed at combating metabolic diseases.

Core competing endogenous RNA network based on mRNA and non-coding RNA expression profiles in chicken fatty liver.

Fatty liver disease is a common metabolic disease in chickens. This disease can lead to a decrease in egg production and increase the risk of death in chickens. Long non-coding RNAs (lncRNAs) are involved in fatty liver formation by directly targeting genes or regulating gene expression by competitively binding microRNAs. However, a large proportion of competing endogenous RNA (ceRNA) networks in fatty liver diseases are still unclear. The total of 300 Jingxing-Huang chickens were used for fatty liver model construction. Then, differentially expressed (DE) genes (DEGs) identified through whole-transcriptome sequencing from four chickens with fatty liver and four chickens without fatty liver were chosen from the F1 generation. A total of 953 DEGs were identified between the fatty liver group and the control group, including 26 DE micro (mi)RNAs and 56 DE lncRNAs. Differential expression heatmaps and volcano plots were obtained after clustering expression analysis. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses revealed that these DEGs were involved in many biological processes and signaling pathways related to fatty acid metabolism and lipid synthesis. Furthermore, cytoscape was used to construct a ceRNA network of the DE miRNAs, DE mRNAs, and DE lncRNAs. Eleven DE lncRNAs, seven DE miRNAs, and 13 DE mRNAs were found to be associated with the pathogenesis of fatty liver disease. An lncRNA-miRNA-mRNA ceRNA network was constructed to elucidate the mechanisms of fatty liver diseases, and the ENSGALT00000079786-miR-140/miR-143/miR-1a/miR-22/miR-375 network was identified. These results provide a valuable resource for further elucidating the posttranscriptional regulatory mechanisms of chicken liver and adipose fat development or deposition.

Functional roles of folic acid in alleviating dexamethasone‐induced fatty liver syndrome in laying hens

AbstractFatty liver syndrome (FLS) poses a threat to the poultry industry due to its high occurrence and mortality rate. Folic acid (FA) is a coenzyme crucial for one‐carbon metabolism. However, the mechanism by which FA mitigates FLS in laying hens remains elusive. In this study, 60 21‐week‐old Hy‐Line Brown layers were divided into three groups: the Control (Con) group, the dexamethasone (DXM) group, and the DXM + FA group. Results showed that liver index was significantly increased in the DXM group. H&E and oil red O staining showed the accumulation of lipid droplets in the liver was intensified, confirming the successful establishment of an early fatty liver model without inflammation. FA significantly reversed hepatic lipid deposition, and 57 differentially expressed genes affected by FA were identified in the transcriptome analysis. Their transcriptional and translational levels indicate that in the early FLS, insulin‐like growth factor 2/phosphatidylinositol‐3‐kinase/protein kinase B pathway related to lipid metabolism was activated; folate cycling was inhibited, while endoplasmic reticulum (ER) stress and apoptosis‐related protein abundance were elevated. Dietary FA enhanced the folate circulation, reduced lipogenesis and ER stress, and apoptosis‐related protein expression, thereby mitigating the lipid metabolism disturbance in FLS. Metabolomics identified 151 differential metabolites involved in early FLS occurrence, 34 of which were reversed by FA. Metabolites were also enriched in pathways related to lipid metabolism and hepatic damage. Collectively, these findings can be concluded that FA can alleviate early FLS by affecting lipogenesis, ER stress and apoptosis, which may be mediated by enhanced folate metabolism.

Paraoxonase-2 agonist vutiglabridin promotes autophagy activation and mitochondrial function to alleviate non-alcoholic steatohepatitis.

Only limited therapeutic agents have been developed for non-alcoholic steatohepatitis (NASH). Glabridin, a promising anti-obesity candidate, has only limited druggability due to its low in vivo chemical stability and bioavailability. Therefore, we developed vutiglabridin (VUTI), which is based on a glabridin backbone, and investigated its mechanism of action in treating NASH in animal models. Anti-NASH effects of VUTI were determined in in vitro fatty liver models, spheroids of primary human hepatocytes and L02 normal liver cell lines. To identify VUTI possible cellular target/s, biotin-labelled VUTI was synthesized and underwent chemical proteomic analysis. Further, the evaluation of VUTI therapeutic efficacy was carried out using an amylin-NASH and high-fat (HF) diet-induced obese (DIO) mouse models. This was carried out using transcriptomic, lipidomic and proteomic analyses of the livers from the amylin-NASH mouse model. VUTI treatment markedly reduces hepatic steatosis, fibrosis and inflammation by promoting lipid catabolism, activating autophagy and improving mitochondrial dysfunction, all of which are hallmarks of effective NASH treatment. The cellular target of VUTI was identified as paraoxonase 2 (PON2), a newly proposed protein target for the treatment of NASH, VUTI enhanced PON2 activity. The results using PON2 knockdown cells demonstrated that PON2 is important for VUTI- activation of autophagy, promoting mitochondrial function, decreasing oxidative stress and alleviating lipid accumulation under lipotoxic condition. Our data demonstrated that VUTI is a promising therapeutic for NASH. Targeting PON2 may be important for improving liver function in various immune-metabolic diseases including NASH.

Anethum graveolens L. restores expression of free fatty acid synthesis-related genes in high fat induced-HepG2 cells

IntroductionThe ethanolic extract of Anethum graveolens (dill) and its major constituents, chlorogenic acid (CGA) and ellagic acid (EA), were investigated for hepatoprotective effects in a HepG2 cell fatty liver model. MethodsHepG2 cells were induced with a combination of oleic (1mM OA) and palmitic (1mM PA) acids and treated with either 10 µM fenofibrate, 1-10 µg/mL CGA or EA, 60-360 µg/mL A. graveolens extract, or left untreated (n=4-5 per group). After 48 hours, cell medium and cells were collected for alanine transaminase (ALT), aspartate transaminase (AST), reactive oxygen species (ROS), and fatty acid accumulation assays. The mRNA and protein expression levels of free fatty acid (FFA) synthetic pathway-related genes were determined using reverse transcription/real-time polymerase chain reaction and Western blotting analysis, respectively. ResultsHepG2 cells treated with OA and PA showed increased ALT, AST, and ROS levels, fatty acid accumulation, and modified mRNA and protein expression of PPAR, SREBP1, ACC, ACOX, FAS, SCD1, and HMGCR fatty acid synthesis-related genes. The CGA, EA, and A. graveolens extract showed hepatoprotective activities in OA and PA-induced HepG2 cells by preventing fatty acid accumulation and restoring mRNA and protein expression levels of the fatty acid synthesis-related genes to control levels, with comparable efficacy to the standard anti-lipidemic drug, fenofibrate. Furthermore, CGA, EA, and A. graveolens extract did not increase ALT and ROS levels in HepG2 cells, in contrast to fenofibrate. ConclusionA. graveolens extract, CGA, and EA are good candidates for development as preventive health supplements for fatty liver disease therapy.

MAPKAP1 orchestrates macrophage polarization and lipid metabolism in fatty liver-enhanced colorectal cancer

Various factors, including fatty liver and macrophage alterations, influence colorectal cancer (CRC). This study explores the mechanistic role of fatty liver in CRC progression, focusing on macrophage polarization and lipid metabolism. A murine fatty liver model was created with a high-fat diet (HFD), and CRC was induced using AOM and DSS. Single-cell transcriptome sequencing (scRNA-seq) identified MAPKAP1 as a critical gene promoting CRC via M2 macrophage polarization and lipid metabolism reprogramming. Prognosis analysis on the TCGA-CRC dataset confirmed MAPKAP1′s significance. In vitro and in vivo experiments demonstrated that EVs from fatty liver cells enhanced MAPKAP1 expression, accelerating CRC development and metastasis. HFD exacerbated CRC, but fatty acid inhibitors delayed progression. Fatty liver upregulates MAPKAP1, driving M2 macrophage polarization and lipid metabolism changes, worsening CRC. These findings suggest potential therapeutic strategies for CRC, particularly targeting lipid metabolism and macrophage-mediated tumor promotion.

Multi-omics analysis of a fatty liver model using human hepatocyte chimeric mice

We developed a fatty liver mouse model using human hepatocyte chimeric mice. As transplanted human hepatocytes do not respond to mouse growth hormone (GH) and tend to accumulate fat, we hypothesized that addition of human GH would alter lipid metabolism and reduce accumulation of fat in the liver even when fed a high-fat diet. Six uPA/SCID chimeric mice were fed a high-fat GAN diet to induce fatty liver while six were fed a normal CRF1 diet, and GH was administered to three mice in each group. The mice were euthanized at 8 weeks, and human hepatocytes were extracted for RNA-Seq, DIA proteomics, and metabolomics analysis. Abdominal echocardiography revealed that the degree of fatty liver increased significantly in mice fed GAN diet (p < 0.001) and decreased significantly in mice treated with GH (p = 0.026). Weighted gene correlation network analysis identified IGF1 and SEMA7A as eigengenes. Administration of GH significantly reduced triglyceride levels and was strongly associated with metabolism of amino acids. MiBiOmics analysis identified perilipin-2 as a co-inertia driver. Results from multi-omics analysis revealed distinct gene expression and protein/metabolite profiles in each treatment group when mice were fed a high-fat or normal diet with or without administration of GH.

Vitamin K2 protects mice against non-alcoholic fatty liver disease induced by high-fat diet

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide and there is a huge unmet need to find safer and more effective drugs. Vitamin K has been found to regulate lipid metabolism in the liver. However, the effects of vitamin K2 on NAFLD is unclear. This study aims to evaluate the preventive and therapeutic effects of vitamin K2 in the process of fatty liver formation and to explore molecular mechanisms the associated with lipid metabolism. A non-alcoholic fatty liver model was established by high-fat diet administration for three months. Vitamin K2 significantly reduced the body weight, abdominal circumference and body fat percentage of NAFLD mice. Vitamin K2 also showed histological benefits in reducing hepatic steatosis. NAFLD mice induced by high-fat diet showed increased HMGR while vitamin K2 intervention could reverse the pathological lterations. Adiponectin (APN) is an endogenous bioactive polypeptide or protein secreted by adipocytes. We detected APN, SOD, AlaDH and other indicators that may affect the state of high-fat diet mice, but the experimental results showed that the above indicators did not change significantly. It is worth noting that the effect of vitamin K2 supplementation on the lipid-lowering effect of uc OC in vivo needs to be further explored. This study first reported the protective effect of vitamin K2 on high-fat diet-induced NAFLD in mice. The protective effect of vitamin K2 may be related to the improvement of lipid metabolism disorder in NAFLD.

Therapeutic effect of autophagy induced by rapamycin versus intermittent fasting in animal model of fatty liver.

High-fructose, high-fat diet consumption (HFHF) is one of the primary causes of non-alcoholic fatt liver disease (NAFLD), which is due to impaired beta-oxidation or apolipoprotein secretion by hepatocytes. Activation of autophagy in hepatocytes could be a therapeutic method against hepatic complications. This study was designed to compare effects of rapamycin and intermittent fasting-inducing autophagy in rats with experimentally induced nonalcoholic fatty liver. Male rats were divided into five groups: C (control, n = 6), the experimental group (EX) subdivided, EXIa (HFHF, n = 6), EXIb (recovery, n = 6), EXII (rapamycin, n = 6) and EXIII (intermittent fasting, n = 6). All rats in the experimental group received HFHF diet for 8 weeks to induce nonalcoholic-fatty liver and obesity. Then, for the next 8 weeks the animals received either a daily oral dose of rapamycin (EXII group) or to intermittent fasting (IF) for 16 hours daily (EXIII group). Blood samples were drawn, and serum TG concentration as well as ALT and AST activities were determined. Hepatic sections were examined by light and electron microscopy. LC3B immunohistochemical staining, morphometric and statistical studies were performed. Subgroups EXIa (HFHF subgroup) and EXIb (Recovery subgroup) showed marked increase in TG, ALT, and AST levels associated with loss of normal hepatic architecture, cytoplasmic vacuolations and faint LC3B immunoreactivity. Ultrathin sections exhibited many autophagosomes in hepatocytes. On the other hand, rapamycin (EXII) and IF (EXIII) groups showed significant improvement to a variable extent in comparison to EXI groups. It could be concluded that rapamycin and intermittent fasting significantly improved NAFLD-induced changes of liver structure and function by inducing autophagy in hepatocytes.

Myeloid-specific deletion of group VIA calcium-independent phospholipase A2 induces pro-inflammatory LPS response predominantly in male mice via MIP-1α activation

Polymorphisms of group VIA calcium-independent phospholipase A2 (PLA2G6) are associated with blood C-reactive protein suggesting its role in inflammation. We showed that myeloid-specific Pla2g6-deficiency in Pla2g6M−/− mice led to exaggerated inflammation and fibrosis in a lean fatty liver model. We here investigated whether these mutants display alteration in immune response after treatment with E. coli lipopolysaccharides (LPS) under acute (a single dose) and persistent (four doses) conditions. Without LPS treatment, male Pla2g6M−/− (but not Flox) mice at 12 months of age exhibited splenomegaly and hepatic necrosis, and ~ 30 % of them exhibited autoimmune hepatitis showing lymphoplasma cells with CD3(+) and CD45R(+) staining. Under acute LPS, male mutants showed an elevation of plasma MIP-1α and immunoglobulinA as well as upregulation of hepatic apoptosis and fibrosis PARP-1, Bax, MCP-1, α-SMA, and collagen I proteins. Their bone-marrow-derived macrophages also showed an elevation of MIP-1α release upon LPS stimulation in vitro. Female mutants under acute LPS showed a moderate increase in plasma KC/CXCL1, MCP-1, and IL10, and they showed no remarkable increase in hepatic fibrosis under acute or persistent LPS. Male mutants under persistent LPS displayed an elevation of aspartate aminotransferase, blood eosinophils, and hepatic apoptosis. Moreover, ~30 % of these mutants exhibited eosinophilic sclerosing portal hepatitis associated with an upregulated protein expression of hepatic CD8α, CD68, eosinophilic cationic protein, and Ly6G. Thus, myeloid-PLA2G6 deficiency led to an autoimmune and LPS-induced inflammatory liver disease via MIP-1α in a male-predominant manner. Our results may be applicable to patients with PLA2G6 mutations who undergo bacterial infection and sepsis.

Betaine for the prevention and treatment of insulin resistance and fatty liver in a high-fat dietary model of insulin resistance in C57BL mice.

The aim was to investigate mechanisms by which betaine improves hepatic insulin signaling in a dietary mouse model of insulin resistance and fatty liver. C57BL 6J mice were fed a standard diet (SF), a standard diet with betaine (SFB), a nutritionally complete high fat (HF) diet, or a high fat diet with betaine (HFB) for 14 weeks. In a separate experiment, mice were fed high fat diet for 18 weeks, half of whom received betaine for the final 4 weeks. Activation of insulin signaling in the liver was assessed by western blot. Insulin signaling was also assessed in insulin resistant primary human hepatocytes treated with betaine. As compared with SF, mice receiving HF diet were heavier, had more hepatic steatosis, and abnormal glucose tolerance test (GTT). Betaine content in liver and serum was 50% lower in HF than in SF; betaine supplementation restored serum and liver betaine content. Betaine treatment of HF reduced whole body insulin resistance as measured by GTT. Betaine treatment of HF increased tyrosine phosphorylation of insulin receptor substrate-1 and phosphorylation (activation) of Akt, and increased hepatic glycogen content. In vitro, betaine reversed insulin resistance in primary human hepatocytes by increasing insulin-stimulated tyrosine phosphorylation of IRS1 and of Akt. Betaine supplementation reduced whole body insulin resistance and increased activation of insulin signaling pathways in the liver in a mouse model of insulin resistance and fatty liver created by feeding a nutritionally complete high fat diet for 14 weeks. Betaine also reduced liver injury as assessed by ALT and by liver histology. In vitro, betaine reversed insulin resistance by increasing insulin-stimulated tyrosine phosphorylation of IRS1 and activation of downstream proteins in the insulin signaling cascade in insulin resistant primary human hepatocytes.

Comparison of the anti-inflammatory and antilipidemic activity of diosmin and saroglitazar in a model of nonalcoholic fatty liver induced by a high-fat diet in Wistar rats.

Non-alcoholic fatty liver disease (NAFLD) is the most common liver-related metabolic disorder in the world, with a global prevalence of 25%. Compounds with anti-inflammatory, lipid-lowering, and insulin-sensitizing properties can be used for the prevention or treatment of NAFLD. Therefore, this study was conducted to investigate the effect of saroglitazar (a dual PPARα/γ agonist) and diosmin (a flavonoid) on non-alcoholic fatty liver induced by a high-fat diet (HFD) in Wistar rats. Forty male Wistar rats (6-8 weeks old) were fed an HFD to induce NAFLD. After 7 weeks, rats were divided into four groups: group1 was fed HFD, and the other groups received HFD+saroglitazar, HFD+diosmin, and HFD+ saroglitazar+diosmin. We examined body and liver weight, histopathology, serum levels of liver enzymes (ALT and AST), and lipid profiles (LDL-C and HDL-C) using the standard protocols. qRT-PCR was also used to examine the expression of PPARα, PPARγ, SREBP1c, FAS, ACC, CPT1α, and pro-inflammatory genes (IL6, TNFα, and TGFβ). Rats fed the HFD showed characteristics of NAFLD (pathologically and biochemically). Administration of saroglitazar and diosmin alone caused a significant decrease in the levels of PPARγ, SREBP1c, FAS, ACC, ALT, AST, LDL-C, and pro-inflammatory genes and a significant increase in PPARα, CPT1a, and HDL-C in comparison with the HF group (P<0.05). Their combined effect was more evident. Our results showed that diosmin, like saroglitazar, significantly ameliorated inflammatory and lipid profiles in HFD-induced NAFLD, suggesting that diosmin, as a natural compound, could be a suitable alternative to saroglitazar.

3D microscaffolds with triple-marker sensitive nanoprobes for studying fatty liver disease in vitro.

Non-alcoholic fatty liver disease (NAFLD) is a heterogeneous condition that encompasses a wide range of liver diseases that progresses from simple hepatic steatosis to the life-threatening state of cirrhosis. However, due to the heterogeneity of this disease, comprehensive analysis of several physicochemical and biological factors that drive its progression is necessary. Therefore, an in vitro platform is required that would enable real-time monitoring of these changes to better understand the progression of these diseases. The earliest stage of NAFLD, i.e. hepatic steatosis, is characterised by triglyceride accumulation in the form of lipid vacuoles in the cytosol of hepatocytes. This fatty acid accumulation is usually accompanied by hepatic inflammation, leading to tissue acidification and dysregulated expression of certain proteases such as matrix metalloproteinases (MMPs). Taking cues from the biological parameters of the disease, we report here a 3D in vitro GelMA/alginate microscaffold platform encapsulating a triple-marker (pH, MMP-3 and MMP-9) sensitive fluorescent nanoprobe for monitoring, and hence, distinguishing the fatty liver disease (hepatic steatosis) from healthy livers on the basis of pH change and MMP expression. The nanoprobe consists of a carbon nanoparticle (CNP) core, which exhibits intrinsic pH-dependent fluorescence properties, decorated either with an MMP-3 (NpMMP3) or MMP-9 (NpMMP9) sensitive peptide substrate. These peptide substrates are flanked with a fluorophore-quencher pair that separates on enzymatic cleavage, resulting in fluorescence emission. The cocktail of these nanoprobes generated multiple fluorescence signals corresponding to slightly acidic pH (blue) and overexpression of MMP-3 (green) and MMP-9 (red) enzymes in a 3D in vitro fatty liver model, whereas no/negligible fluorescence signals were observed in a healthy liver model. Moreover, this platform enabled us to mimic fatty liver disease in a more realistic manner. Therefore, this 3D in vitro platform encapsulating triple-marker sensitive fluorescent nanoprobes would facilitate the monitoring of the changes in pH and MMP expression, thereby enabling us to distinguish a healthy liver from a diseased liver and to study liver disease stages on the basis of these markers.