High-fat High-cholesterol Diet Research Articles

ApoE Receptor-2 R952Q Variant in Macrophages Elevates Soluble LRP1 to Potentiate Hyperlipidemia and Accelerate Atherosclerosis in Mice.

apoER2 (apolipoprotein E receptor-2) is a transmembrane receptor in the low-density lipoprotein receptor (LDLR) family with unique tissue expression. A single-nucleotide polymorphism that encodes the R952Q sequence variant has been associated with elevated plasma cholesterol levels and increased myocardial infarction risk in humans. The objective of this study was to delineate the mechanism underlying the association between the apoER2 R952Q variant and increased atherosclerosis risk. An apoER2 R952Q mouse model was generated using a CRISPR/Cas9 strategy, intercrossed with LDLR knockout mice, followed by feeding a Western-type high-fat high-cholesterol diet for 16 weeks. Atherosclerosis was investigated by immunohistology. Plasma lipids and lipid distributions among the various lipoprotein classes were analyzed by colorimetric assay. Tissue-specific effects of the R952Q sequence variant on atherosclerosis were analyzed by bone marrow transplant studies. sLRP1 (soluble low-density lipoprotein receptor-related protein 1) was measured in plasma and conditioned media from bone marrow-derived macrophages by ELISA and GST-RAP (glutathione S-transferase-receptor-associated protein) pull-down, respectively. P38 MAPK (mitogen-activated protein kinase) phosphorylation in VLDL (very-low-density lipoprotein)-treated macrophages was determined by Western blot analysis. Consistent with observations in humans with this sequence variant, the apoER2 R952Q mutation exacerbated diet-induced hypercholesterolemia, via impediment of plasma triglyceride-rich lipoprotein clearance, to accelerate atherosclerosis in Western diet-fed LDLR knockout mice. Reciprocal bone marrow transplant experiments revealed that the apoER2 R952Q mutation in bone marrow-derived cells instead of non-bone marrow-derived cells was responsible for the increase in hypercholesterolemia and atherosclerosis. Additional data showed that the apoER2 R952Q mutation in macrophages promotes VLDL-induced LRP1 (low-density lipoprotein receptor-related protein 1) shedding in a p38 MAPK-dependent manner. The apoER2 R952Q mouse model recapitulates characteristics observed in human disease. The underlying mechanism is that the apoER2 R952Q mutation in macrophages exacerbates VLDL-stimulated sLRP1 production in a p38 MAPK-dependent manner, resulting in its competition with cell surface LRP1 to impede triglyceride-rich lipoprotein clearance, thereby resulting in increased hypercholesterolemia and accelerated atherosclerosis.

Aerobic exercise alleviates statin-induced PCSK9 upregulation by increasing epoxyeicosatrienoic acid levels through the FoxO3a-Sirt6 axis

BackgroundStatins are the cornerstone of low-density lipoprotein cholesterol (LDL-C)-lowering therapy; however, the therapeutic efficacy of statins in countering atherosclerotic cardiovascular disease (ASCVD) is compromised by the concurrent elevation of proprotein convertase subtilisin/kexin type 9 (PCSK9), a pivotal molecule that increases LDL-C levels. Aerobic exercise lowers PCSK9 levels, but the underlying mechanism remains unclear. Therefore, we investigated how aerobic exercise can ameliorate statin-induced increases in PCSK9 levels. MethodsThree-week-old male American Institute of Cancer Research (ICR) mice were fed a high-fat-cholesterol diet (HFD) for 12 weeks and then administered atorvastatin alone or atorvastatin combined with aerobic exercise (Statin+Ex). Moreover, a total of 165 participants with stable coronary heart disease (CHD) enrolled at the inpatient and outpatient departments of the Second Xiangya Hospital of Central South University from January 2018 to July 2020 were randomized into the Statin group (male/female = 51/33) and Statin+Ex group (male/female = 52/29). Patients in the Statin+Ex group underwent treadmill exercise of 45–60 min/day for 7 days. ResultsAerobic exercise effectively alleviated statin-induced PCSK9 upregulation in human patients with CHD and hypercholesterolemic ICR mice (all p< 0.05). Mechanistically, our findings revealed that aerobic exercise induced elevated epoxyeicosatrienoic acids (EETs) plasma levels while concurrently reducing the activity of soluble epoxide hydrolase (sEH) (all p < 0.05), an enzyme responsible for EETs degradation. Further, EETs significantly suppressed PCSK9 expression, subsequently reducing the LDL-C levels (all p < 0.05); this effect was mediated via the activation of the Forkhead box O3a-Silent mating type information regulation 2 homolog 6 (FoxO3a-Sirt6) axis, with no impact on the Sterol Regulatory Element Binding Protein 2 and 3-hydroxy-3-methylglutaryl-CoA reductase(SREBP2-HMGCR) pathway. ConclusionOur study sheds light on the paradigm of "Exercise is Medicine", providing evidence to support the use of statins combined with exercise in reducing LDL-C levels, and unveils potential avenues for clinical applications of sEH inhibitors, presenting novel prospects for therapeutic interventions in ASCVD.

Low-dose valine attenuates diet-induced metabolic dysfunction-associated steatotic liver disease (MASLD) in mice by enhancing leptin sensitivity and modulating the gut microbiome

Elevated circulating branched-chain amino acids (BCAAs) have been associated with obesity, insulin resistance, and MASLD, yet BCAA supplementation has been shown to provide protective outcomes towards the intervention of MASLD. Currently, there is a lack of study towards the contribution of the BCAA: valine on MASLD. This study investigates the effects of low-dose valine supplementation on MASLD in a high-fat/high-cholesterol diet (HFD) model. Low-dose valine was found to attenuate the progression of MASLD, significantly reducing body weight, liver weight, and eWAT weight, attenuating hyperglycemia and improving serum lipid profiles. It also decreased hyperleptinemia and enhanced hypothalamic leptin sensitivity, leading to reduced food intake. In the eWAT, metabolic flexibility was improved, as indicated by upregulated adipogenesis-related gene expressions and suppressed leptin expression. In the liver, valine improved hepatic leptin sensitivity, alleviated hepatic steatosis, and reduced triglycerides, cholesterol, TNFα, and IL-6 levels. Mechanistically, valine increased hepatic antioxidant capacity and modulated lipid metabolism and antioxidant pathways, downregulating de novo lipogenesis and cholesterol synthesis while increasing fatty acid oxidation, autophagy-related gene expressions. Moreover, hepatic AMPK pathway activity was enhanced, contributing to improved leptin sensitivity and signalling. Additionally, low-dose valine supplementation also modulated the gut microbiome, suggesting a multifaceted approach to managing MASLD.

Evaluation of the role of hepatic Gstm4 in diet-induced obesity and dyslipidemia

Obesity and its related diseases continue to rise worldwide, necessitating further investigation to develop new therapeutic strategies. The dysregulation of redox homeostasis is tightly associated with metabolic diseases. Glutathione, an antioxidant, acts as a cofactor for antioxidant and detoxification enzymes such as glutathione S-transferases (GSTs)—a superfamily including Gstm4. So far, the physiological role of Gstm4 remains largely unknown. Human genetics is a powerful tool to discover novel therapeutic targets for metabolic diseases. The single nucleotide polymorphism rs650985, located within the sixth intron of the human gene Gstm4, was associated with plasma lipids, indicating that targeting Gstm4 might intervene in the progression of dyslipidemia. Furthermore, we found that Gstm4 is highly expressed in the liver and enriched in hepatocytes—the parenchymal cells of the liver. We established the mouse model with the hepatic deletion of Gstm4 and found that this mouse model did not present altered body weight, serum lipid profile, or liver fat content in the context of chow or high-fat high cholesterol diet feeding, indicating that hepatic Gstm4 is dispensable for diet-induced obesity and dyslipidemia. Further analysis revealed that hepatic deletion of Gstm4 upregulates the level of protein but not mRNA of Npc1l1—a critical protein mediating cholesterol uptake, suggesting that there might be a link between Gstm4 and lipid metabolic diseases in certain contexts.

MicroRNA-411-5p alleviates lipid deposition in metabolic dysfunction-associated steatotic liver disease by targeting the EIF4G2/FOXO3 axis

BackgroundAbnormal lipid deposition is an important driver of the progression of metabolic dysfunction-associated steatotic liver disease (MASLD). MicroRNA-411-5p (miR-411-5p) and eukaryotic translation initiation factor 4γ2 (EIF4G2) are related to abnormal lipid deposition, but the specific mechanism is unknown.MethodsA high-fat, high-cholesterol diet (HFHCD) and a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) and a high-fructose diet (HFrD) were used to establish MASLD rat and mouse models, respectively. MiR-411-5p agomir and mimic were used to upregulate the miR-411-5p in vivo and in vitro, respectively. Adeno-associated virus type 8 (AAV8) carrying EIF4G2 short hairpin RNA (shRNA) and small interfering RNA (siRNA) were used to downregulate the EIF4G2 expression in vivo and in vitro, respectively. Liver histopathological analysis, Biochemical analysis and other experiments were used to explore the functions of miR-411-5p and EIF4G2.ResultsMiR-411-5p was decreased in both MASLD rats and mice, and was negatively correlated with liver triglycerides and serum alanine transaminase (ALT) and aspartate transaminase (AST) levels. Upregulation of miR-411-5p alleviated liver lipid deposition and hepatocellular steatosis. Moreover, miR-411-5p targeted and downregulated EIF4G2. Downregulation of EIF4G2 not only reduced liver triglycerides and serum ALT and AST levels in MASLD model, but also alleviated lipid deposition. Notably, upregulation of miR-411-5p and downregulation of EIF4G2 led to the reduction of forkhead box class O3 (FOXO3) and inhibited the expression of sterol regulatory-element binding protein 1 (SREBP1), acetyl-CoA carboxylase 1 (ACC1) and fatty acid synthase (FASN), thereby reducing fatty acid synthesis.ConclusionsUpregulation of miR-411-5p inhibits EIF4G2 to reduce the FOXO3 expression, thereby reducing fatty acid synthesis and alleviating abnormal lipid deposition in MASLD.

Protective role of S-adenosylmethionine on high fat/high cholesterol diet-induced hepatic and aortic lesions and oxidative stress in guinea pigs.

S-adenosylmethionine (SAM) is the main methyl group donor and has antioxidant potential. In this study, preventive and regressive potential of SAM were investigated in high fat/high cholesterol (HFHC) diet-induced non-alcoholic fatty liver disease (NAFLD) in guinea pigs. They were injected with SAM (50 mg/kg, i.p.) for 6 weeks along with HFHC diet or 4 weeks after HFHC diet. Serum transaminase activities, total cholesterol (TC), triglyceride (TG), cytochrome p450-2E1 (CYP2E1) and hydroxyproline (Hyp) levels, prooxidative and antioxidative parameters, protein expressions of α-smooth muscle actin (α-SMA) and transforming growth factor-β1 (TGF-β1) together with histopathological changes were examined in the liver. SAM treatment diminished HFHC diet-induced increases in serum transaminase activities and hepatic TC, TG, CYP2E1, Hyp, α-SMA and TGF-β1 expressions and ameliorated prooxidant-antioxidant balance. Histopathological scores for hepatic steatosis, inflammation, and fibrosis were decreased by SAM treatment. Increases in TC, diene conjugate levels, and lipid vacuoles within the tunica media of the aorta were reduced in HFHC-fed animals treated with SAM. These protective effects were also detected in the regression period of HFHC-guinea pigs due to SAM. In conclusion, SAM treatment was found to be effective in prevention and regression of HFHC-induced hepatic and aortic lesions together with decreases in oxidative stress in guinea pigs with NAFLD.

GTPBP8 mitigates nonalcoholic steatohepatitis (NASH) by depressing hepatic oxidative stress and mitochondrial dysfunction via PGC-1α signaling

Nonalcoholic steatohepatitis (NASH) is emerging as a major cause of liver transplantation and hepatocellular carcinoma (HCC). Regrettably, its pathological mechanisms are still not fully comprehended. GTP-binding protein 8 (GTPBP8), belonging to the GTP-binding protein superfamily, assumes a crucial role in RNA metabolism, cell proliferation, differentiation, and signal transduction. Its aberrant expression is associated with oxidative stress and mitochondrial dysfunctions. Nevertheless, its specific functions and mechanisms of action, particularly in NASH, remain elusive. In our current study, we initially discovered that human hepatocytes L02 displayed evident mitochondrial respiratory anomaly, mitochondrial damage, and dysfunction upon treatment with palmitic acids and oleic acids (PO), accompanied by significantly reduced GTPBP8 expression levels through RNA-Seq, RT-qPCR, western blotting, and immunofluorescence assays. We then demonstrated that GTPBP8 overexpression mediated by adenovirus vector (Ad-GTPBP8) markedly attenuate lipid accumulation, inflammatory response, and mitochondrial impair and dysfunction in hepatocytes stimulated by PO. Conversely, adenovirus vector-mediated GTPBP8 knockdown (Ad-shGTPBP8) significantly accelerated lipid deposition, inflammation and mitochondrial damage in PO-treated hepatocytes in vitro. Furthermore, we constructed an in vivo NASH murine model by giving a 16-week high fat high cholesterol diet (HFHC) diet to hepatocyte specific GTPBP8-knockout (GTPBP8HKO) mice. We firstly found that HFHC feeding led to metabolic disorder in mice, including high body weight, blood glucose and insulin levels, and liver dysfunctions, which were accelerated in these NASH mice with GTPBP8 deficiency in hepatocytes. Consistently, GTPBP8HKO remarkably exacerbated the progression of NASH phenotypes induced by HFHC, as proved by the anabatic lipid accumulation, inflammation, fibrosis and reactive oxygen species (ROS) production in liver tissues, which could be largely attributed to the severe mitochondrial damage and dysfunction. Mechanistically, we further identified that GTPBP8 interacted with peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in hepatocytes. Importantly, the hepaprotective effects of GTPBP8 against mitochondrial dysfunction, oxidative stress and inflammation was largely dependent on PGC-1α expression. Collectively, GTPBP8 may exert a protective role in the progression of NASH, and targeting the GTPBP8/PGC-1α axis may represent a potential strategy for NASH treatment by improving mitochondrial functions.

Integrating Lipidomics, Metabolomics, and Network Pharmacology to Reveal the Mechanism of Cannabidiol against Inflammation in High-Fat, High-Cholesterol Diet-Induced Mice.

Inflammation plays a critical role in the development of numerous diseases. Cannabidiol (CBD), found in hemp, exhibits significant pharmacological activities. Accumulating evidence suggests that CBD has anti-inflammatory and cardiovascular protection effects, but the potential mechanisms require further exploration. In this study, we aimed to reveal the mechanisms of CBD against high-fat, high-cholesterol (HFC) diet-induced inflammation combining metabolomics with network pharmacology. First, plasma lipidomics results indicated that oxidized lipids could serve as potential biomarkers for HFC diet-induced inflammation, and CBD reversed the elevated levels of oxidized lipids. The HFC diet was also found to enhance intestinal permeability, facilitating the entry of lipopolysaccharides (LPSs) into the circulatory system and subsequently increasing systemic inflammation. Additionally, cell metabolomic results indicated that CBD could reverse 10 important differential metabolites in LPS-induced RAW 264.7 cells. Using network pharmacology, we identified 49 core targets, and enrichment analysis revealed that arachidonic acid was the most significantly affected by CBD, which was closely associated with inflammation. Further integrated analysis focused on three key targets, including PTGS2, ALOX5, and ALOX15. Molecular docking showed high affinities between key targets and CBD, and qPCR further demonstrated that CBD could reverse the mRNA expression of these key targets in RAW 264.7 cells. Collectively, this finding integrates lipidomics and metabolomics with network pharmacology to elucidate the anti-inflammatory effects of CBD and validates key therapeutic targets.

Hepatic miR-363 promotes nonalcoholic fatty liver disease by suppressing INSIG1

Nonalcoholic fatty liver disease (NAFLD) constitutes one of major worldwide health problem which typically progressively results in nonalcoholic steatohepatitis (NASH) and eventually cirrhosis and liver cancer. Liver-specific deletion of INSIG1 promotes SREBP1 nuclear translocation to activate downstream lipogenic genes expression, leading to lipid accumulation. However, the underlying pathogenesis of NAFLD, and particularly involved in miRNA participation are still to be thoroughly explored. Here, we found that miR-363-3p was significantly overexpressed in high-fat, high-cholesterol (HFHC) diet mice liver tissue and fatty acid-induced steatosis cells. miR-363-3p directly targets INSIG1 to inhibit its expression, thereby facilitating the cleavage of SREBP and nuclear translocation to activate subsequent transcription of lipogenic genes in vitro and in vivo. In addition, we identified apigenin, a natural flavonoid compound, inhibited miR-363-3p expression to up-regulate INSIG1 and suppress nuclear translocation of SREBP1, thereby down-regulated lipogenic genes expression in steatosis cells and HFHC diet mice liver tissues. Taken together, our results demonstrated that miR-363-3p as a key regulator of hepatic lipid homeostasis targeted INSIG1, and apigenin alleviated NAFLD through the miR-363-3p/INSIG1/SREBP1 pathway. This indicates that reduction of miR-363-3p levels as a possible treatment of hepatic steatosis and provides a potential new therapeutic strategy for targeting miRNA to ameliorate NAFLD.

Native and Gd-EOB-DTPA-Enhanced T1 mapping for Assessment of Liver Fibrosis in NAFLD: Comparative Analysis of Modified Look-Locker Inversion Recovery and Water-specific T1 mapping

Rationale and ObjectivesTo investigate the diagnostic performance of water-specific T1 mapping for staging liver fibrosis in a non-alcoholic fatty liver disease (NAFLD) rabbit model, in comparison to Modified Look-Locker Inversion recovery (MOLLI) T1 mapping. Materials and methodsSixty rabbits were randomly divided into the control group (12 rabbits) and NAFLD model groups (8 rabbits per subgroup) corresponding to different durations of high-fat high cholesterol diet feeding. All rabbits underwent MRI examination including MOLLI T1 mapping and 3D multi-echo variable flip angle (VFAME- GRE) sequences were acquired before and 20min after the administration of Gd- EOB-DTPA. Histological assessments were performed to evaluate steatosis, inflammation, ballooning, and fibrosis. Statistical analysis included the intraclass correlation coefficient, analysis of variance, spearman correlation, multiple linear regression, and receiver operating characteristic curve. ResultsA moderate correlation was observed between conventional native T1 and MRI-PDFF (r=-0.513, P<0.001), as well as between conventional native T1 and liver steatosis grades (r=-0.319, P=0.016). However, no significant correlation was found between the native wT1 and PDFF (r=0.137, P=0.314), or between the native wT1 and steatosis grades (r=0.106, P=0.435). In the multiple regression analysis, liver fibrosis, and hepatocellular ballooning were identified as independent factors influencing native wT1 in this study (R2=0.545, P<0.05), while steatosis was independently associated with conventional native T1 (R2=0.321, P<0.005). The AUC values for native T1, native wT1, HBP T1, and HBP wT1 were 0.549(0.410-0.682), 0.811(0.684-0.903), 0.775(0.644-0.876), and 0.752(0.619-0.858) for F1 or higher, 0.581(0.441-0.711), 0.828(0.704-0.916), 0.832(0.708-0.919), and 0.854(0.734-0.934) for F2 or higher, respectively. ConclusionThe native wT1 may provide a more reliable assessment of early liver fibrosis in the context of NAFLD compared to conventional native T1.

Intestinal NSD2 Aggravates Nonalcoholic Steatohepatitis Through Histone Modifications.

Mounting clinical evidence suggests that a comprised intestinal barrier contributes to the progression of nonalcoholic steatohepatitis (NASH); nevertheless, the precise mechanism remains elusive. This study unveils a significant upregulation of nuclear receptor-binding SET domain protein 2 (NSD2) in the intestines of obese humans and mice subjected to a high-fat cholesterol diet (HFCD). Intestine-specific NSD2 knockout attenuated the progression of intestinal barrier impairment and NASH, whereas NSD2 overexpression exacerbated this progression. Mechanistically, NSD2 directly regulates the transcriptional activation of Ern1 by demethylating histone H3 at lysine 36 (H3K36me2), thus activating the ERN1-JNK axis to intensify intestinal barrier impairment and subsequently foster NASH progression. These findings elucidate the crucial role of NSD2-mediated H3K36me2 in intestinal barrier impairment, suggesting that targeting intestinal NSD2 can represent a novel therapeutic approach for NASH.

Enterocyte-specific FATP4 deficiency elevates blood lipids via a shift from polar to neutral lipids in distal intestine.

Fatty acid transport protein (FATP)4 was thought to mediate intestinal lipid absorption, which was disputed by a study using keratinocyte-Fatp4-rescued Fatp4-/- mice. These knockouts when fed with a Western diet showed elevated intestinal triglyceride (TG) and fatty acid levels. To investigate a possible role of FATP4 on intestinal lipid processing, ent-Fatp4 (KO) mice were generated by Villin-Cre-specific inactivation of the Fatp4 gene. We aimed to measure circulating and intestinal lipids in control and KO mice after acute or chronic fat intake or during aging. Remarkably, ent-Fatp4 mice displayed an approximately 30% decrease in ileal behenic, lignoceric, and nervonic acids, ceramides containing these FA, as well as, ileal sphingomyelin, phosphatidylcholine, and phosphatidylinositol levels. Such decreases were concomitant with an increase in jejunal cholesterol ester. After a 2-wk recovery from high lipid overload by tyloxapol and oral-lipid treatment, ent-Fatp4 mice showed an increase in plasma TG and chylomicrons. Upon overnight fasting followed by an oral fat meal, ent-Fatp4 mice showed an increase in plasma TG-rich lipoproteins and the particle number of chylomicrons and very low-density lipoproteins. During aging or after feeding with a high-fat high-cholesterol (HFHC) diet, ent-Fatp4 mice showed an increase in plasma TG, fatty acids, glycerol, and lipoproteins as well as intestinal lipids. HFHC-fed KO mice displayed an increase in body weight, the number of lipid droplets with larger sizes in the ileum, concomitant with a decrease in ileal ceramides and phosphatidylcholine. Thus, enterocyte FATP4 deficiency led to a metabolic shift from polar to neutral lipids in distal intestine rendering an increase in plasma lipids and lipoproteins.NEW & NOTEWORTHY Enterocyte-specific Fatp4 deficiency in mice increased intestinal lipid absorption with elevation of blood lipids during fasting and aging, as well as after an acute oral fat-loading or chronic HFHC feeding. Lipidomics revealed that knockout mice displayed a shift from very long-chain to long-chain fatty acids, and from polar to neutral lipids, predominantly in the ileum. Thus, FATP4 may have a physiological function in the control of blood lipids via metabolic shifts in distal intestine.

Efficacy and mechanism of action of Yanxiao Di'naer formula for non-alcoholic steatohepatitis treatment based on metabolomics and RNA sequencing

Ethnopharmacological relevanceNonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease worldwide. Nonalcoholic steatohepatitis (NASH) is a crucial component of this disease spectrum. The Yanxiao Di'naer formula (YXDNE) is an Uyghur medical extract that has been used in folk medicine to treat hepatitis for a long time. However, the role and mechanism of action of YXDNE in NASH treatment remains unclear. ObjectiveThe objective of this study was to assess the effectiveness of YXDNE in treating NASH induced by injections of carbon tetrachloride combined with a high-fat high-cholesterol diet (HFHCD), and to clarify the underlying mechanisms. MethodsThe compounds in the YXDNE extract were analysed for classification and proportions using ultra-performance liquid chromatography-mass spectrometry. The efficacy of YXDNE in treating abnormal lipid metabolism was evaluated in L02 cells in vitro. In addition, a C57BL/6 mouse model of NASH was established to evaluate the therapeutic efficacy of YXDNE in vivo. Metabolomics and RNA sequencing were used to analyse the therapeutic effects of YXDNE on the liver. The corresponding signalling pathways were found to target AMPKα1, PPARα, and NF-κB. The efficacy of YXDNE was validated using inhibitors or silencing RNA (siRNA) against AMPKα1 and PPARα. ResultsThis study confirmed that YXDNE treatment ameliorated NASH in a murine model of this disease. Metabolomics analysis suggested that YXDNE efficacy was associated with fatty acid catabolism and AMPK signalling pathways. RNA sequencing results showed that YXDNE efficacy in treating NASH was highly correlated with the AMPK, PPARα and NF-κB pathways. Both in vitro and in vivo experimental data demonstrated that YXDNE affected the expression of p-AMPKα1, PPARα, p–NF–κB, IκB, and p-IκB. The efficacy of YXDNE in treating NASH in vitro was cancelled when AMPK was inhibited with Compound C or PPARα was modulated via siRNA. ConclusionsYXDNE may have a therapeutic effect on abnormal lipid metabolism in L02 cells and in a murine model of NASH by affecting the AMPKα1/PPARα/NF-κB signalling pathway. Therefore, YXDNE has the potential for clinical application in the prevention and treatment of NASH.

Metabolomics analyses reveal the liver-protective mechanism of Wang's metabolic formula on metabolic-associated fatty liver disease

Wang's metabolic formula (WMF) is a traditional Chinese medicine formula developed under the guidance of Professor Kungen Wang. WMF has been clinically utilized for several years. However, the therapeutic mechanism of WMF in treating metabolic-associated fatty liver disease (MAFLD) remains unclear. In this study, we performed phytochemical analysis on WMF using LC-MS. To study the role of WMF in MAFLD, we orally administered WMF (20.6 g/kg) to male MAFLD mice induced by a high-cholesterol high-fat diet (HCHFD). Then pathological, biochemical, and metabolomic analyses were performed. The main components of WMF are chlorogenic acid, geniposide, albiflorin, paeoniflorin, and calycosin-7-O-glucoside. MAFLD mice treated with WMF exhibited significant improvements in obesity, abnormal lipid metabolism, inflammation, and liver pathology. WMF decreased aspartate aminotransferase (AST), alanine aminotransferase (ALT), and triglyceride (TG) levels in the serum of MAFLD mice while increasing high-density lipoprotein cholesterol (HDL-c) levels. WMF lowered liver TG levels and inflammatory factors (IL-1β, IL-6, TNF-α, and NF-κB). Metabolomic analysis of the liver annotated 78 differentially regulated metabolites enriched in four pathways: glycerophospholipid metabolism, retinol metabolism, PPAR signaling pathway, and choline metabolism. Western blot experiments showed that WMF increased the expression of PPAR-α, PPAR-β, and RXR in the liver while decreasing the expression of RAR. The study demonstrates that WMF has a solid preventive and therapeutic effect on MAFLD. The anti-inflammatory and regulation of abnormal liver metabolism activities of WMF involve retinol metabolism and the PPAR signaling pathway.

MicroRNA-206 as a potential cholesterol-lowering drug is superior to statins in mice

Hypercholesterolemia is frequently intertwined with hepatosteatosis, hypertriglyceridemia, and hyperglycemia. This study is designed to assess the therapeutic efficacy of miR-206 in contrast to statins in the context of managing hypercholesterolemia in mice. We previously showed that miR-206 is a potent inhibitor of de novo lipogenesis (DNL), cholesterol synthesis, and gluconeogenesis in mice. Given that these processes occur within hepatocytes, we employed a mini-circle (MC) system to deliver miR-206 specifically to hepatocytes (designated as MC-miR-206). A single intravenous injection of MC-miR-206 maintained high levels of miR-206 in the liver for at least two weeks, thereby maintaining suppression of hepatic DNL, cholesterol synthesis, and gluconeogenesis. MC-miR-206 significantly reduced DNA damage, endoplasmic reticulum and oxidative stress, and hepatic toxicity. Therapeutically, both MC-miR-206 and statins significantly reduced total serum cholesterol and triglycerides as well as LDL cholesterol and VLDL cholesterol in mice maintained on the normal chow and high-fat high-cholesterol diet. MC-miR-206 reduced liver weight, hepatic triglycerides and cholesterol, and blood glucose, while statins slightly increased hepatic cholesterol and blood glucose and failed to affect levels of liver weight and hepatic triglycerides. Mechanistically, miR-206 alleviated hypercholesterolemia by inhibiting hepatic cholesterol synthesis, while statins increased HMGCR activity, hepatic cholesterol synthesis, and fecal-neutral steroid excretion. MiR-206 facilitates the regression of hypercholesterolemia, hypertriglyceridemia, hyperglycemia, and hepatosteatosis. MiR-206 outperforms statins by reducing hyperglycemia, hepatic cholesterol levels, and hepatic toxicity.

Tomato juice regulates bile acid-TGR5 signaling and reverses cognitive deficit and neuroinflammation in high-fat high-cholesterol diet-induced mice

Cognitive deficits and neuroinflammation are significant complications associated with metabolic diseases induced by a high-fat, high-cholesterol (HFHC) diet. Although tomato juice (TJ) has shown potential benefits for brain health, its specific interventional role remains unclear. This research examined the capability of TJ to mitigate HFHC-induced cognitive deficits and delineated TJ's specific mechanisms against neuroinflammation. The results demonstrated that TJ effectively ameliorated cognitive impairments triggered by HFHC diets, improving spatial working memory, novel object recognition, and reducing anxiety-like behaviors in open space and elevated maze tests. Moreover, TJ mitigated neuronal damage, decreased the activity of immune cells, and diminished the level of COX-2 and iNOS in the hippocampus. Additionally, TJ decreased serum TNF-α and lipopolysaccharide levels, reduced liver inflammation, and improved intestinal barrier markers Claudin-1 and Mucin-2 expression. Fecal metabolomics demonstrated that TJ significantly upregulated bile acid metabolism-related pathways. TJ also altered the profile of serum bile acids, elevating the levels of Takeda G protein-coupled receptor 5 (TGR5)-activating bile acids, including deoxycholic acid, ursodeoxycholic acid, and tauroursodeoxycholic acid. TJ upregulated TGR5 protein expression and inhibited the phosphorylation of protein kinase B and nuclear factor kappa B proteins in the hippocampus. Notably, the positive effects of TJ on cognition and TGR5 activation were nullified in an antibiotic-treated mouse model, underscoring the essential role of the gut-brain axis in mediating TJ's neuroprotective effects. These findings propose that bile acid-TGR5 signaling may be associated with the anti-neuroinflammatory effects of TJ, which may represent a novel approach for neurogenic disease prevention.

Therapeutic Targeting of PKM2 Ameliorates NASH Fibrosis Progression in a Macrophage-Specific and Liver-Specific Manner

Nonalcoholic steatohepatitis (NASH) may soon become the leading cause of end-stage liver disease worldwide with limited treatment options. Liver fibrosis, which is driven by chronic inflammation and hepatic stellate cell (HSC) activation, critically determines morbidity and mortality in patients with NASH. Pyruvate kinase M2 (PKM2) is involved in immune activation and inflammatory liver diseases; however, its role and therapeutic potential in NASH-related fibrosis remain largely unexplored. Bioinformatics screening and analysis of human and murine NASH livers indicated that PKM2 was upregulated in nonparenchymal cells (NPCs), especially macrophages, in the livers of patients with fibrotic NASH. Macrophage-specific PKM2 knockout (PKM2FL/FLLysM-Cre) significantly ameliorated hepatic inflammation and fibrosis severity in three distinct NASH models induced by a methionine- and choline-deficient (MCD) diet, a high-fat high-cholesterol (HFHC) diet, and a western diet plus weekly carbon tetrachloride injection (WD/CCl4). Single-cell transcriptomic analysis indicated that deletion of PKM2 in macrophages reduced profibrotic Ly6Chigh macrophage infiltration. Mechanistically, PKM2-dependent glycolysis promoted NLR family pyrin domain containing 3 (NLRP3) activation in proinflammatory macrophages, which induced HSC activation and fibrogenesis. A pharmacological PKM2 agonist efficiently attenuated the profibrotic crosstalk between macrophages and HSCs in vitro and in vivo. Translationally, ablation of PKM2 in NPCs by cholesterol-conjugated heteroduplex oligonucleotides, a novel oligonucleotide drug that preferentially accumulates in the liver, dose-dependently reversed NASH-related fibrosis without causing observable hepatotoxicity. The present study highlights the pivotal role of macrophage PKM2 in advancing NASH fibrogenesis. Thus, therapeutic modulation of PKM2 in a macrophage-specific or liver-specific manner may serve as a novel strategy to combat NASH-related fibrosis.

Neoagarotetraose Alleviates Atherosclerosis via Modulating Cholesterol and Bile Acid Metabolism in ApoE-/- Mice.

Atherosclerosis is closely associated with metabolic disorders such as cholesterol accumulation, bile acid metabolism, and gut dysbiosis. Neoagarotetraose supplementation has been shown to inhibit obesity and alleviate type 2 diabetes, but its effects on modulating the development of atherosclerosis remain unexplored. Therefore, the present study was conducted to investigate the protective effects and potential mechanisms of neoagarotetraose on high-fat, high-cholesterol diet (HFHCD)-induced atherosclerosis in ApoE-/- mice. The results showed that neoagarotetraose supplementation decreased the atherosclerotic lesion area by 50.1% and the aortic arch lesion size by 80.4% compared to the HFHCD group. Furthermore, neoagarotetraose supplementation led to a significant reduction in hepatic lipid content, particularly non-high-density lipoprotein cholesterol. It also resulted in a substantial increase in total bile acid content in both urine and fecal samples by 3.0-fold and 38.7%, respectively. Moreover, neoagarotetraose supplementation effectively downregulated the intestinal farnesoid X receptor by 35.8% and modulated the expressions of its associated genes in both the liver and intestine. In addition, correlation analysis revealed strong associations between gut microbiota composition and fecal bile acid levels. These findings highlight the role of gut microbiota in neoagarotetraose-mitigating atherosclerosis in HFHCD-fed ApoE-/- mice. This study indicates the potential of neoagarotetraose as a functional dietary supplement for the prevention of atherosclerosis.

Doenjang Ameliorates Diet-Induced Hyperlipidemia and Hepatic Oxidative Damage by Improving Lipid Metabolism, Oxidative Stress, and Inflammation in ICR Mice.

Hyperlipidemia, characterized by elevated cholesterol, lipids, and triglycerides in the bloodstream, is linked to hepatic oxidative damage. Doenjang, a traditional Korean condiment made from fermented soybeans, is known for its health benefits, yet its anti-hyperlipidemic effects remain understudied. Our study aimed to assess the hypolipidemic and hepatic protective effects of Doenjang on male ICR mice fed a high-fat cholesterol diet for 8 weeks. Mice were divided into three groups: the normal diet (ND), the high-fat cholesterol diet (HD), and the Doenjang-supplemented HD diet (DS) group. Doenjang supplementation significantly regulated total cholesterol, triglycerides, LDL cholesterol, and HDL cholesterol levels compared to the HD group. It also downregulated lipogenic genes, including PPARγ, FAS, and ACC, and positively influenced the cholesterol metabolism-related genes HMGCR and LXR. Moreover, Doenjang intake increased serum glutathione levels, activated oxidative stress defense genes (NRF2, SOD, GPx1, and CAT), positively modulated inflammation genes (NF-kB and IL6) in hepatic tissue, and reduced malondialdehyde levels. Our findings highlight the effectiveness of traditional Doenjang in preventing diet-induced hyperlipidemia and protecting against hepatic oxidative damage.

Enavogliflozin, an sglt2 inhibitor, improves nonalcoholic steatohepatitis induced by high-fat high-cholesterol diet

Enavogliflozin, an sglt2 inhibitor, improves nonalcoholic steatohepatitis induced by high-fat high-cholesterol diet