Liraglutide ameliorates nonalcoholic fatty liver disease in diabetic mice via the IRS2/PI3K/Akt signaling pathway

The Role of Tripartite Motif Family Proteins in Chronic Liver Diseases: Molecular Mechanisms and Therapeutic Potential

The worldwide impact of liver diseases is increasing steadily, with a consistent upswing evidenced in incidence and mortality rates. Chronic liver diseases (CLDs) refer to the liver function's progressive deterioration exceeding six months, which includes abnormal clotting factors, detoxification failure, and hepatic cholestasis. The most common etiologies of CLDs are mainly composed of chronic viral hepatitis, MAFLD/MASH, alcoholic liver disease, and genetic factors, which induce inflammation and harm to the liver, ultimately resulting in cirrhosis, the irreversible final stage of CLDs. The latest research has shown that tripartite motif family proteins (TRIMs) function as E3 ligases, which participate in the progression of CLDs by regulating gene and protein expression levels through post-translational modification. In this review, our objective is to clarify the molecular mechanisms and potential therapeutic targets of TRIMs in CLDs and provide insights for therapy guidelines and future research.

Bta-miR-200a Regulates Milk Fat Biosynthesis by Targeting IRS2 to Inhibit the PI3K/Akt Signal Pathway in Bovine Mammary Epithelial Cells

Milk fat synthesis has garnered significant attention due to its influence on the quality of milk. Recently, an increasing amount of proofs have elucidated that microRNAs (miRNAs) are important post-transcriptional factor involved in regulating gene expression and play a significant role in milk fat synthesis. MiR-200a was differentially expressed in the mammary gland tissue of dairy cows during different lactation periods, which indicated that miR-200a was a candidate miRNA involved in regulating milk fat synthesis. In our research, we investigated the potential function of miR-200a in regulating milk fat biosynthesis in bovine mammary epithelial cells (BMECs). We discovered that miR-200a inhibited cellular triacylglycerol (TAG) synthesis and suppressed lipid droplet formation; at the same time, miR-200a overexpression suppressed the mRNA and protein expression of milk fat metabolism-related genes, such as fatty acid synthase (FASN), peroxisome proliferator-activated receptor gamma (PPARγ), sterol regulatory element-binding protein 1 (SREBP1), CCAAT enhancer binding protein alpha (CEBPα), etc. However, knocking down miR-200a displayed the opposite results. We uncovered that insulin receptor substrate 2 (IRS2) was a candidate target gene of miR-200a through the bioinformatics online program TargetScan. Subsequently, it was confirmed that miR-200a directly targeted the 3'-untranslated region (3'-UTR) of IRS2 via real-time fluorescence quantitative PCR (RT-qPCR), western blot analysis, and dual-luciferase reporter gene assay. Additionally, IRS2 knockdown in BMECs has similar effects to miR-200a overexpression. Our research set up the mechanism by which miR-200a interacted with IRS2 and discovered that miR-200a targeted IRS2 and modulated the activity of the PI3K/Akt signaling pathway, thereby taking part in regulating milk fat synthesis in BMECs. Our research results provided valuable information on the molecular mechanisms for enhancing milk quality from the view of miRNA-mRNA regulatory networks.

Structural abnormality of hepatic glycogen in rat liver with diethylnitrosamine-induced carcinogenic injury

Growing evidence confirms associations between glycogen metabolic re-wiring and the development of liver cancer. Previous studies showed that glycogen structure changes abnormally in liver diseases such as cystic fibrosis, diabetes, etc. However, few studies focus on glycogen molecular structural characteristics during liver cancer development, which is worthy of further exploration. In this study, a rat model with carcinogenic liver injury induced by diethylnitrosamine (DEN) was successfully constructed, and hepatic glycogen structure was characterized. Compared with glycogen structure in the healthy rat liver, glycogen chain length distribution (CLD) shifts towards a short region. In contrast, glycogen particles were mainly present in small-sized β particles in DEN-damaged carcinogenic rat liver. Comparative transcriptomic analysis revealed significant expression changes of genes and pathways involved in carcinogenic liver injury. A combination of transcriptomic analysis, RT-qPCR, and western blot showed that the two genes, Gsy1 encoding glycogen synthase and Gbe1 encoding glycogen branching enzyme, were significantly altered and might be responsible for the structural abnormality of hepatic glycogen in carcinogenic liver injury. Taken together, this study confirmed that carcinogenic liver injury led to structural abnormality of hepatic glycogen, which provided clues to the future development of novel drug targets for potential therapeutics of carcinogenic liver injury.

The role of TRIM family in metabolic associated fatty liver disease

Metabolic associated fatty liver disease (MAFLD) ranks among the most prevalent chronic liver conditions globally. At present, the mechanism of MAFLD has not been fully elucidated. Tripartite motif (TRIM) protein is a kind of protein with E3 ubiquitin ligase activity, which participates in highly diversified cell activities and processes. It not only plays an important role in innate immunity, but also participates in liver steatosis, insulin resistance and other processes. In this review, we focused on the role of TRIM family in metabolic associated fatty liver disease. We also introduced the structure and functions of TRIM proteins. We summarized the TRIM family's regulation involved in the occurrence and development of metabolic associated fatty liver disease, as well as insulin resistance. We deeply discussed the potential of TRIM proteins as targets for the treatment of metabolic associated fatty liver disease.

Targeted MicroRNA Profiling Reveals That Exendin-4 Modulates the Expression of Several MicroRNAs to Reduce Steatosis in HepG2 Cells

Excess hepatic lipid accumulation is the hallmark of non-alcoholic fatty liver disease (NAFLD), for which no medication is currently approved. However, glucagon-like peptide-1 receptor agonists (GLP-1RAs), already approved for treating type 2 diabetes, have lately emerged as possible treatments. Herein we aim to investigate how the GLP-1RA exendin-4 (Ex-4) affects the microRNA (miRNAs) expression profile using an in vitro model of steatosis. Total RNA, including miRNAs, was isolated from control, steatotic, and Ex-4-treated steatotic cells and used for probing a panel of 799 highly curated miRNAs using NanoString technology. Enrichment pathway analysis was used to find the signaling pathways and cellular functions associated with the differentially expressed miRNAs. Our data shows that Ex-4 reversed the expression of a set of miRNAs. Functional enrichment analysis highlighted many relevant signaling pathways and cellular functions enriched in the differentially expressed miRNAs, including hepatic fibrosis, insulin receptor, PPAR, Wnt/β-Catenin, VEGF, and mTOR receptor signaling pathways, fibrosis of the liver, cirrhosis of the liver, proliferation of hepatic stellate cells, diabetes mellitus, glucose metabolism disorder and proliferation of liver cells. Our findings suggest that miRNAs may play essential roles in the processes driving steatosis reduction in response to GLP-1R agonists, which warrants further functional investigation.

Pharmaceutical Strategies to Improve Druggability of Potential Drug Candidates in Nonalcoholic Fatty Liver Disease Therapy

Nonalcoholic fatty liver disease (NAFLD) has become globally prevalent and is the leading cause of chronic liver disease. Although NAFLD is reversible without medical intervention in the early stage, the condition could be sequentially worsened to nonalcoholic steatohepatitis (NASH) and, eventually, cirrhosis and hepatic cancer. The progression of NAFLD is related to various factors such as genetics, pre-disposed metabolic disorders, and immunologic factors. Thankfully, to date, there have been accumulating research efforts and, as a result, different classes of potent drug candidates have been discovered. In addition, there have also been various attempts to explore pharmaceutical strategies to improve the druggability of drug candidates. In this review, we provided a brief overview of the drug candidates that have undergone clinical trials. In the latter part, strategies for developing better drugs are discussed.

Vitamin D3 alleviates nonalcoholic fatty liver disease in rats by inhibiting hepatic oxidative stress and inflammation via the SREBP-1-c/ PPARα-NF-κB/IR-S2 signaling pathway

Introduction: Nonalcoholic fatty liver disease (NAFLD) is a chronic disease characterized by fat deposits in liver cells, which can lead to hepatitis and fibrosis. This study attempted to explore the protective effect of vitamin D3 (VitD) against NAFLD. Methods: Adult male albino rats were randomized into four separate groups: the negative control group was fed a standard rat chow; the positive group received a high-fat diet (20%) and 25% fructose water (NAFLD); the VitD control group was intramuscularly treated with VitD (1,000 IU/kg BW) 3 days per week for 10 weeks; and the NAFLD group was treated with VitD therapy. Biochemical and hepatic histological analyses were performed. Hepatic oxidative stress and inflammatory conditions were also studied. Hepatic expression of sterol regulatory element-binding protein 1-c (SREBP-1-c), peroxisome proliferator-activated receptor alpha (PPAR-α), and insulin receptor substrate-2 was analyzed by quantitative real-time polymerase chain reaction. Results and discussion: The NAFLD rats exhibited elevated terminal body weight, hepatic injury markers, dyslipidemia, glucose intolerance, and insulin resistance. Moreover, the NAFLD rats had increased SREBP-1-c expression and reduced PPAR-α and IRS-2 expressions. Histological analysis showed hepatic steatosis and inflammation in the NAFLD group. In contrast, VitD administration improved the serum biochemical parameters and hepatic redox status in NAFLD rats. Also, VitD treatment ameliorated hepatic inflammation and steatosis in the NAFLD group by decreasing the expression of SREBP-1-c and increasing the expression of PPAR-α. Overall, these results suggest that VitD could have a protective effect against NAFLD and its associated complication.

Investigation of the potential mechanism of the Shugan Xiaozhi decoction for the treatment of nonalcoholic fatty liver disease based on network pharmacology, molecular docking and molecular dynamics simulation

Background

Nonalcoholic fatty liver disease (NAFLD) is a metabolic disease, the incidence of which increases annually. Shugan Xiaozhi (SGXZ) decoction, a composite traditional Chinese medicinal prescription, has been demonstrated to exert a therapeutic effect on NAFLD. In this study, the potential bioactive ingredients and mechanism of SGXZ decoction against NAFLD were explored via network pharmacology, molecular docking, and molecular dynamics simulation.

Methods

Compounds in SGXZ decoction were identified and collected from the literature, and the corresponding targets were predicted through the Similarity Ensemble Approach database. Potential targets related to NAFLD were searched on DisGeNET and GeneCards databases. The compound-target-disease and protein-protein interaction (PPI) networks were constructed to recognize key compounds and targets. Functional enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) was performed on the targets. Molecular docking was used to further screen the potent active compounds in SGXZ. Finally, molecular dynamics (MD) simulation was applied to verify and validate the binding between the most potent compound and targets.

Results

A total of 31 active compounds and 220 corresponding targets in SGXZ decoction were collected. Moreover, 1,544 targets of NAFLD were obtained, of which 78 targets intersected with the targets of SGXZ decoction. Key compounds and targets were recognized through the compound-target-disease and PPI network. Multiple biological pathways were annotated, including PI3K-Akt, MAPK, insulin resistance, HIF-1, and tryptophan metabolism. Molecular docking showed that gallic acid, chlorogenic acid and isochlorogenic acid A could combine with the key targets. Molecular dynamics simulations suggested that isochlorogenic acid A might potentially bind directly with RELA, IL-6, VEGFA, and MMP9 in the regulation of PI3K-Akt signaling pathway.

Conclusion

This study investigated the active substances and key targets of SGXZ decoction in the regulation of multiple-pathways based on network pharmacology and computational approaches, providing a theoretical basis for further pharmacological research into the potential mechanism of SGXZ in NAFLD.

Potential role of gut microbiota-LCA-INSR axis in high fat-diet-induced non-alcoholic fatty liver dysfunction: From perspective of radiation variation

Non-alcoholic fatty liver disease (NAFLD) is a progressive disease of the liver covering a range of conditions from hepatic steatosis to liver fibrosis. NAFLD could be induced by High-fat-diet(HFD). Ionizing radiation is widely used in medical diagnosis and therapy as well as is a common risk factor in occupational environment. Whether the exposure of various dose of radiation has effects on HFD-induced NAFLD remains unclear. Here, we reported that radiation exposure promoted HFD-induced NAFLD in a dose-response manner. Furthermore, the gut microbiota composition had significant difference among mice with or without radiation treatment. Specifically, the Bacteroidetes/Firmicutes ratio, the abundance of A. muciniphila, Butyricococcus, and Clostridiaceae decreased significantly in the mice with co-exposure of high dose of radiation and HFD treatment. A fecal transplantation trial (FMT) further verified the role of gut microbiota in the regulation of the liver response to co-exposure of high dose of radiation and HFD treatment. Notably, the gut microbiome analysis showed plasma lithocholic acid (LCA) level increased in the mice with co-exposure of high dose of radiation and HFD treatment. Following antibiotic and probiotic treatments there was a significantly decreased LCA bile acid concentration and subsequent promotion of INSR/PI3K/Akt insulin signaling in the liver tissues. Our results demonstrate that the co-exposure of radiation and HFD aggravates the HFD-induced NAFLD through gut microbiota-LCA-INSR axis. Probiotics supplementation is a potential way to protect against co-exposure of radiation and HFD-induced liver damage. Meanwhile, our study provide a new insight that population with potential HFD-induced damage should pay more attention on preventing from liver damage while exposing radiation.

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Gut microbiota-lithocholic acid-insulin receptor (LCA-INSR) axis involves the promotion effects of radiation on HFD-induced NAFLD.

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Probiotics improve the liver damage induced by co-exposure of radiation and HFD.

Alternative to Sugar, Honey Does Not Provoke Insulin Resistance in Rats Based on Lipid Profiles, Inflammation, and IRS/PI3K/AKT Signaling Pathways Modulation

Insulin resistance (IR) is the central link to metabolic syndrome (MS), and IR prevention has become the key to overcoming this worldwide public health problem. A diet rich in simple sugars is an important pathogenic factor in IR development. To investigate the effect of honey on IR compared to the sugar-water diet, we analyzed phenolics and oligosaccharides in jujube honey and rape honey based on LC-MS and silane derivatization/GC-MS. The effects of different diets on glucose and lipid profile, histopathology and IR-related mechanism pathways were analyzed and compared by equal sugar levels intervention of fructose, fructose + glucose and two kinds of unifloral honey (high-/low-dose) in rats. The results suggested that sugar-equivalent honey, which differs from sugar solution, especially 17.1 g/kg BW jujube honey rich in phenolics (1.971 mg/100 g of isoquercitrin) and oligosaccharides (2.18 g/100 g of turanose), suppressed IR via maintaining glucose (OGTT and ITT) and lipid (TC, TG, LDL-C, HDL-C, and NEFA) homeostasis, improving histological structural abnormalities of the liver, adipose and skeletal muscle, reducing oxidative stress (GSH-Px and MDA) and inflammation (IL-6 and TNF-α), modulating the NF-κB (NF-κB gene expression was down-regulated to 0.94) and IRS/PI3K/AKT signaling pathways (e.g., AKT and GLUT2 expression in liver increased by 4.56 and 13.37 times, respectively) as well as reshaping the gut microbiota. These revealed a potential nutritional contribution of substituting honey for simple sugar in the diet, providing a theoretical basis for controlling IR development via dietary modification and supplementation.

Effects of Resveratrol Against Induced Metabolic Syndrome in Rats: Role of Oxidative Stress, Inflammation, and Insulin Resistance

Metabolic syndrome (MS) is a serious health problem associated with an increase in risk factors for hepatic steatosis, which is the most common liver disease today. The goal of this study was to investigate the protective effects of resveratrol against metabolic alterations associated with a high-fat high-fructose diet (HFFD). Thirty-two male rats were randomly divided into four equal groups: control (cont.), metabolic syndrome (MS), resveratrol (Res), and metabolic syndrome treated with resveratrol (MS + Res). Resveratrol was administrated orally at a dose of 30 mg/kg·bw, daily. After 10 weeks, body weight, serum biochemical parameters, hepatic oxidative stress, inflammatory markers, as well as mRNA levels of hepatic genes related to lipid metabolism and insulin signaling were measured. In addition, the liver was examined histopathologically to detect lipid deposition. Increased body weight, hepatic dysfunction, dyslipidemia, hepatic insulin resistance, hepatic oxidative and inflammatory stress conditions, upregulation of mRNA expression level of sterol regulatory element binding protein 1-c (SREBP1-c), and downregulation of mRNA expression levels of peroxisome proliferated activated receptor alpha (PPARα) and insulin receptor substrate-2 (IR-S2) were all observed in the MS rats. Hepatic steatosis was confirmed by hematoxylin and eosin and Oil Red O staining. Administration of resveratrol reduced liver steatosis, oxidative stress, and inflammatory state. Also, it improved lipid profile as well as insulin sensitivity and reverted alterations in hepatic mRNA expression levels of the tested genes. Based on these findings, resveratrol could be proposed as a therapeutic approach for MS prevention.

Metformin improves high‑fat diet‑induced insulin resistance in mice by downregulating the expression of long noncoding RNA NONMMUT031874.2

Metformin (MET) is the first-line therapeutic option for patients with type 2 diabetes that has garnered substantial attention over recent years. However, an insufficient number of studies have been performed to assess its effects on insulin resistance and the expression profile of long noncoding RNAs (lncRNAs). The present study divided mice into three groups: Control group, high-fat diet (HFD) group and HFD + MET group. A high-throughput sequencing analysis was conducted to detect lncRNA and mRNA expression levels, and differentially expressed lncRNAs were selected. Subsequently, the differentially expressed lncRNAs were validated both in vivo and in vitro (mouse liver AML12 cells treated with Palmitic acid) models of insulin resistance. After validating randomly selected lncRNAs via reverse transcription-quantitative PCR a novel lncRNA, NONMMUT031874.2, was identified, which was upregulated in the HFD group and reversed with MET treatment. To investigate the downstream mechanism of NONMMUT031874.2, lncRNA-microRNA (miR/miRNA)-mRNA co-expression network was constructed and NONCODE, miRBase and TargetScan databases were used, which indicated that NONMMUT031874.2 may regulate suppressor of cytokine signaling 3 by miR-7054-5p. For the in vitro part of the present study, AML12 cells were transfected with small interfering RNA to knock down NONMMUT031874.2 expression before being treated with palmitic acid (PA) and MET. The results showed that the expression of NONMMUT031874.2 was significantly increased whereas miR-7054-5p expression was significantly decreased by PA treatment. By contrast, after knocking down NONMMUT031874.2 expression or treatment with MET, the aforementioned in vitro observations were reversed. In addition, it was also found that NONMMUT031874.2 knockdown and treatment with MET exerted similar effects in alleviating insulin resistance and whilst decreasing glucose concentration in AML12 cells. These results suggest that MET treatment can ameliorate insulin resistance by downregulating NONMMUT031874.2 expression.

Purendan alleviates non-alcoholic fatty liver disease in aged type 2 diabetic rats via regulating mTOR/S6K1/SREBP-1c signaling pathway

Older people are more likely to develop insulin resistance and lipid metabolism disorders. Purendan (PRD) is a clinically verified traditional Chinese medicine compound, which plays an obvious role in regulating lipid metabolism disorder and improving insulin sensitivity. Our study aimed to investigate the efficacy and mechanism of PRD on aged type 2 diabetes mellitus (T2DM) complicated with non-alcoholic fatty liver disease (NAFLD) rats. Sprague-Dawley rats (13 months) were fed with high-fat diet (HFD) and injected with low-dose STZ to replicate T2DM model. PRD was treated at three concentrations with metformin as a positive control. After administration, blood and liver tissue samples were collected to measure glucose metabolism indexes such as serum glucose and insulin, as well as lipid metabolism indexes such as TC, TG, LDL, HDL and FFA. Liver fat accumulation was observed by HE staining and oil red O staining. And protein expression levels of mTOR, p-mTOR, S6K1, p-S6K1 and SREBP-1c were detected by western blot. After PRD treatment, not only the insulin sensitivity and insulin resistance were significantly improved, but also the TC, TG, LDL, FFA, AST and ALT in serum and the lipid accumulation in liver tissue were significantly decreased. Moreover, PRD significantly down-regulated the expression of p-mTOR, p-S6K1 and SREBP-1c in liver tissues. In conclusion, PRD can alleviate NAFLD in aged T2DM rats by inhibiting the mTOR /S6K1/ SREBP-1c pathway.

The Roles of Liver Inflammation and the Insulin Signaling Pathway in PM2.5 Instillation-Induced Insulin Resistance in Wistar Rats

To elucidate the mechanism of how the liver participates in PM2.5-caused insulin resistance. A novel Wistar rat model was developed in this study by instilling a suspension of lyophilized PM2.5 sample (2.5 mg/kg, 5 mg/kg, or 10 mg/kg) collected from the atmosphere. Systemic insulin resistance indicators, including serum fasting blood glucose (FBG), fasting insulin (FINS), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), and hemoglobin A1 (HbA1), were upregulated by the PM2.5 instillation. The area under the curve (AUC_glu) calculated by intraperitoneal glucose tolerance testing (IPGTT) was also significantly greater in the PM2.5 instillation groups. Additionally, PM2.5 instillation was found to cause liver damage and inflammation. The serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (TBIL), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were significantly elevated by PM2.5 instillation. PM2.5 also triggered IL-6 and TNF-α transcription but inhibited mRNA synthesis and suppressed signaling activation of the insulin-phosphoinositide 3-kinase- (PI3K-) Akt-glucose transporter 2 (GLUT2) pathway in the rat liver by reducing the ratio of phosphorylated Akt to phosphorylated insulin receptor substrate 1 (IRS-1). Thus, PM2.5-induced inflammation activation and insulin signaling inhibition in the rat liver contribute to the development of systemic insulin resistance.

Anthocyanins from the fruits of Lycium ruthenicum Murray improve high-fat diet-induced insulin resistance by ameliorating inflammation and oxidative stress in mice

A high-fat diet (HFD) promotes tissue inflammation, oxidative stress and insulin resistance (IR), thereby contributing to the development of obesity and diabetes. Anthocyanins from Lycium ruthenicum (AC) have demonstrated anti-obesity effects and modulated IR. To investigate the mechanism by which AC attenuates the adverse effects of consuming a HFD, C57BL/6J mice were fed a HFD supplemented with AC or a control diet without AC for 12 weeks. AC supplementation decreased the amount of weight gain, hepatic lipid, and sequentially improved dyslipidemia, inflammation, oxidative stress, and IR in HFD-fed mice. Molecular data revealed that AC inhibited hepatic inflammation by reducing TLR4/NF-κB/JNK in the liver tissues and ameliorated oxidative stress by activating the Nrf2/HO-1/NQO1 pathway. Thus, AC might activate IRS-1/AKT and prevent HFD-induced gluconeogenesis and IR by ameliorating inflammation and oxidative stress. Modulation of inflammation and oxidative stress with AC may represent a promising target for the treatment of IR and provide insight into the mechanism by which AC protects against obesity.

Liraglutide or insulin glargine treatments improves hepatic fat in obese patients with type 2 diabetes and nonalcoholic fatty liver disease in twenty-six weeks: A randomized placebo-controlled trial

BACKGROUND

Type 2 diabetes mellitus is closely related to nonalcoholic fatty liver disease(NAFLD). More and more attention has been paid to the efficacy of liraglutide in the treatment of NAFLD, but the clinical evidence is still insufficient.

OBJECTIVE

The purpose of this study was to use proton magnetic resonance spectroscopy (H-MRS) assessment of metformin alone poor blood glucose control of obese patients type 2 diabetes with NAFLD, added with insulin glargine, liraglutide or placebo effect in improving the fatty liver.

METHODS

This is a 26-week, single-center, prospective, randomized placebo-controlled study. From September 2016 to July 2018, 128 patients with type 2 diabetes and NAFLD were enrolled in the China joint logistics team 900 hospital. The primary endpoints were the changes in intrahepatic content of lipid (IHCL), abdominal adiposity [subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT)], from baseline to week 26 (end of treatment) and the changes in liraglutide group or insulin glargine group versus change in placebo group. Secondary endpoints included the changes in liver function (AST and ALT), glycemia (HbA1c and FPG), body weight, and BMI.

RESULTS

A total of 96 patients with type 2 diabetes and NAFLD under inadequate glycemic control by metformin were randomized (1:1:1) to receive add-on insulin glargine, liraglutide, or placebo. After 26 weeks of treatment, compared to the placebo group, in the liraglutide and insulin glargine groups, IHCL significantly decreased from baseline to week 26 (liraglutide 26.4% ± 3.2% to 20.6% ± 3.9%, P < 0.05; insulin glargine 25.0% ± 4.3% to 22.6% ± 5.8%, P > 0.05). SAT and VAT decreased significantly in the liraglutide group and in the insulin glargine group (P < 0.05). ΔSAT and ΔVAT were greater with liraglutide than insulin glargine, they were significantly different between the two groups (ΔSAT, -36 vs. - 24.5, P < 0.05; and ΔVAT, -47 vs. - 16.6, P > 0.05). In the liraglutide group, AST, ALT, and HOMA-IR decreased significantly from baseline. There was no significant difference in glucose-lowering among the three groups. During the treatment, the safety of the three groups performed well.

CONCLUSION

Compared with placebo, treatment with liraglutide plus an adequate dose of metformin (2000 g/ day) for 26 weeks is more effective in reducing IHCL, SAT and VAT in patients with type 2 diabetes and NAFLD. And it has additional advantages in weight loss, waist circumference reduction and liver function improvement.

Role of potato protein hydrolysate and exercise in preventing high-fat diet-induced hepatocyte apoptosis in senescence-accelerated mouse

Nonalcoholic fatty liver disease (NAFLD) is considered to be a serious clinical complication, which could cause significant liver dysfunction including fibrosis, cirrhosis, and cancer. Obesity could lead to NAFLD and contributes to liver disorder and related complicated liver diseases. Effect of exercise combined with alcalase treatment derived potato protein hydrolysate (APPH) on high-fat diet (HFD)-induced hepatic injury was investigated in senescence accelerated mouse-prone 8 (SAMP8) mice in the present study. Mice were divided into six groups (n = 6): Group I-Control, Group II-HFD, Group III-Exercise, Group IV-HFD + APPH, Group V-HFD + Exercise, and Group VI-HFD + Exercise + APPH. Combined APPH treatment and exercise offer better cytoprotection in HFD-induced histological changes than APPH treatment and exercise alone. Further, APPH and exercise activate the cell survival proteins PI3K/Akt and prevent FasL/FADD-mediated apoptosis in HFD fed SAMP8 mouse. APPH with swimming exercise effectively modulate HFD-induced liver damage and apoptosis in aged mice through activation of PI3K/Akt protein. PRACTICAL APPLICATIONS: Exercise training is proven to reduce the health problems associated with aging and obesity, however, intensity and duration of the exercise differs between individuals. We used integrated pharmacological and nonpharmacological approach as a therapeutic strategy for preventing HFD-induced hepatic injury in aged subjects.

Liraglutide Improves Non-Alcoholic Fatty Liver Disease In Diabetic Mice By Modulating Inflammatory Signaling Pathways

BACKGROUND

Many chronic metabolic diseases, such as obesity and type 2 diabetes (T2DM), are closely related to a chronic low-grade inflammatory state in tissues. The high prevalence of non-alcoholic fatty liver disease (NAFLD) in patients with T2DM is related to the role of inflammation in the disease. In this study, we investigated the role of liraglutide in improving lipid metabolism disorders and preventing their progression to NAFLD by modulating inflammatory signaling pathways, thereby providing new treatment options for NAFLD.

METHODS

We designed a 2×2 factorial analysis experiment. A mouse model of NAFLD with T2DM was established by feeding the animals a high-fat diet (HFD). The NAFLD mice with HFD-induced diabetes were treated with liraglutide for 10 weeks. Hematoxylin and eosin staining, Oil Red O staining and electron microscopy were used to observe the accumulation of triglycerides in the liver. RT-PCR and Western blotting were used to analyze the expression of α-SMA, IL-1β, TNF-α, NF-κB and the NF-κB inhibitory protein IκB in the liver at the gene and protein levels, respectively.

RESULTS

Liraglutide reduced the body weight and fasting blood glucose levels of HFD-fed mice. The expression of α-SMA, IL-1β, TNF-α, and NF-κB in the liver of HFD-fed mice was increased at the mRNA and protein levels, but liraglutide treatment decreased the expression of these molecules. The expression of IκB in the liver decreased at the mRNA and protein levels but was upregulated after liraglutide treatment.

CONCLUSION

Based on the current findings, liraglutide can significantly improve hepatic steatosis, primarily by downregulating the expression of inflammatory signaling mediators in the TNF-α pathway.