Hepatocellular Lipid Research Articles

TOMM40 regulates hepatocellular and plasma lipid metabolism via an LXR-dependent pathway

The gene encoding TOMM40 (Transporter of Outer Mitochondrial Membrane 40) is adjacent to that encoding APOE, which has a central role in lipid and lipoprotein metabolism. Human genetic variants near APOE and TOMM40 are strongly associated with plasma lipid levels, but a specific role for TOMM40 in lipid metabolism has not been established. We show here that suppression of TOMM40 in human hepatoma cells upregulates expression of APOE and LDLR in part via activation of LXRB (NR1H2) by oxysterols, with consequent increased uptake of VLDL and LDL. This is in part due to disruption of mitochondria-endoplasmic reticulum contact sites, with resulting accrual of reactive oxygen species and non-enzymatically derived oxysterols. With TOMM40 knockdown, cellular triglyceride and lipid droplet content are increased, effects attributable in part to receptor-mediated VLDL uptake, since lipid staining is significantly reduced by concomitant suppression of either LDLR or APOE. In contrast, cellular cholesterol content is reduced due to LXRB-mediated upregulation of the ABCA1 transporter as well as increased production and secretion of oxysterol-derived cholic acid. Consistent with the findings in hepatoma cells, in vivo knockdown of TOMM40 in mice results in significant reductions of plasma triglyceride and cholesterol concentrations, reduced hepatic cholesterol and increased triglyceride content, and accumulation of lipid droplets leading to development of steatosis. These findings demonstrate a role for TOMM40 in regulating hepatic lipid and plasma lipoprotein levels and identify mechanisms linking mitochondrial function with lipid metabolism.

Effect of a multidisciplinary lifestyle intervention on body composition in people with osteoarthritis: Secondary analysis of the “Plants for Joints” randomized controlled trial

ObjectiveThe Plants for Joints (PFJ) intervention significantly improved pain, stiffness, and physical function, and metabolic outcomes, in people with metabolic syndrome-associated osteoarthritis (MSOA). This secondary analysis investigated its effects on body composition. MethodIn the randomized PFJ study, people with MSOA followed a 16-week intervention based on a whole-food plant-based diet, physical activity, and stress management, or usual care. For this secondary analysis, fat mass, muscle mass, and bone mineral density were measured using dual-energy X-ray absorptiometry (DEXA) for all participants. Additionally, in a subgroup (n ​= ​32), hepatocellular lipid (HCL) content and composition of visceral adipose tissue (VAT) were measured using magnetic resonance spectroscopy (MRS). An intention-to-treat analysis with a linear-mixed model adjusted for baseline values was used to analyse between-group differences. ResultsOf 66 people randomized, 64 (97%) completed the study. The PFJ group experienced significant weight loss (−5.2 ​kg; 95% CI –6.9, −3.6) compared to controls, primarily from fat mass reduction (−3.9 ​kg; 95% CI –5.3 to −2.5). No significant differences were found in lean mass, muscle strength, or bone mineral density between groups. In the subgroup who underwent MRI scans, the PFJ group had a greater reduction in HCL (−6.5%; 95% CI –9.9, 3.0) compared to controls, with no observed differences in VAT composition. ConclusionThe PFJ multidisciplinary intervention positively impacted clinical and metabolic outcomes, and appears to significantly reduce body fat, including liver fat, while preserving muscle mass and strength.

GCKIII kinases control hepatocellular lipid homeostasis via shared mode of action

Metabolic dysfunction–associated steatotic liver disease has emerged as a leading global cause of chronic liver disease. Our recent translational investigations have shown that the STE20-type kinases comprising the GCKIII subfamily—MST3, STK25, and MST4—associate with hepatic lipid droplets and regulate ectopic fat storage in the liver; however, the mode of action of these proteins remains to be resolved. By comparing different combinations of the silencing of MST3, STK25, and/or MST4 in immortalized human hepatocytes, we found that their single knockdown results in a similar reduction in hepatocellular lipid content and metabolic stress, without any additive or synergistic effects observed when all three kinases are simultaneously depleted. A genome-wide yeast two-hybrid screen of the human hepatocyte library identified several interaction partners contributing to the GCKIII-mediated regulation of liver lipid homeostasis, that is, PDCD10 that protects MST3, STK25, and MST4 from degradation, MAP4K4 that regulates their activity via phosphorylation, and HSD17B11 that controls their action via a conformational change. Finally, using in vitro kinase assays on microfluidic microarrays, we pinpointed various downstream targets that are phosphorylated by the GCKIII kinases, with known functions in lipogenesis, lipolysis, and lipid secretion, as well as glucose uptake, glycolysis, hexosamine synthesis, and ubiquitination. Together, this study demonstrates that the members of the GCKIII kinase subfamily regulate hepatocyte lipid metabolism via common pathways. The results shed new light on the role of MST3, STK25, and MST4, as well as their interactions with PDCD10, MAP4K4, and HSD17B11, in the control of liver lipid homeostasis and metabolic dysfunction–associated steatotic liver disease susceptibility.

Role of patatin-like phospholipase domain-containing 3 gene for decreasing kidney function in recently diagnosed diabetes mellitus

AimsWe examined the association of the G allele in the single-nucleotide polymorphism (SNP) rs738409 in the third exon of patatin-like phospholipase domain-containing 3 gene (PNPLA3) gene, with chronic kidney disease in diabetes endotypes. MethodsParticipants with recent-onset diabetes (n=707) from the prospective German Diabetes Study (GDS) underwent cluster assignment, detailed phenotyping, genotyping and magnetic resonance spectroscopy to quantify hepatocellular lipid content (HCL). ResultsSevere insulin-resistant diabetes (SIRD) had the lowest glomerular filtration rates (eGFR) and highest HCL compared to severe insulin-deficient, moderate obesity-related, moderate age-related and severe autoimmune diabetes endotypes (all p<0.05). HCL was negatively associated with eGFR (r=-0.287, p<0.01) across all groups. Stratification by G-allele carrier status did not reveal any association between HCL and eGFR among the endotypes. However, the proportion of G-allele carriers increased from 44% for eGFR >60 ml/min to 52% for eGFR <60 ml/min (p<0.05). ConclusionsThe PNPLA3 polymorphism may contribute to declining kidney function independently of liver lipids.

Protective effects of Nogo-B deficiency in NAFLD mice and its multiomics analysis of gut microbiology and metabolism

BackgroundNonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver ailment that can lead to serious conditions such as cirrhosis and hepatocellular carcinoma. Hepatic Nogo-B regulates glucose and lipid metabolism, and its inhibition has been shown to be protective against metabolic syndrome. Increasing evidence suggests that imbalances in the gut microbiota (GM) and lipid metabolism disorders are significant contributors to NAFLD progression. Nevertheless, it is not yet known whether Nogo-B can affect NAFLD by influencing the gut microbiota and metabolites. Hence, the aim of the present study was to characterize this process and explore its possible underlying mechanisms.MethodsA NAFLD model was constructed by administering a high-fat diet (HFD) to Nogo-B−/− and WT mice from the same litter, and body weight was measured weekly in each group. The glucose tolerance test (GTT) and insulin tolerance test (ITT) were performed to assess blood glucose levels. At the end of the 12-week period, samples of serum, liver, and intestinal contents were collected and used for serum biochemical marker and inflammatory factor detection; pathology evaluation; and gut microbiome and metabolomics analysis. Spearman’s correlation analysis was performed to determine possible correlations between differential gut microbiota and differential serum metabolites between groups.ResultsNogo-B deficiency attenuated the effects of the HFD, including weight gain, liver weight gain, impaired glucose tolerance, hepatic steatosis, elevated serum lipid biochemicals levels, and liver function. Nogo-B deficiency suppressed M1 polarization and promoted M2 polarization, thus inhibiting inflammatory responses. Furthermore, Nogo-B−/−-HFD-fed mice presented increased gut microbiota richness and diversity, decreased Firmicutes/Bacteroidota (F/B) ratios, and altered serum metabolites compared with those of WT-HFD-fed mice. During analysis, several differential gut microbiota, including Lachnoclostridium, Harryflintia, Odoribacter, UCG-009, and unclassified_f_Butyricoccaceae, were screened between groups. These microbiota were found to be positively correlated with upregulated purine metabolism and bile acid metabolites in Nogo-B deficiency, while they were negatively correlated with downregulated corticosterone and tricarboxylic acid cyclic metabolites in Nogo-B deficiency.ConclusionNogo-B deficiency delayed NAFLD progression, as demonstrated by reduced hepatocellular lipid accumulation, attenuated inflammation and liver injury, and ameliorated gut microbiota dysbiosis and metabolic disorders. Importantly, Odoribacter was strongly positively correlated with ALB and taurodeoxycholic acid, suggesting that it played a considerable role in the influence of Nogo-B on the progression of NAFLD, a specific feature of NAFLD in Nogo-B−/− mice. The regulation of bile acid metabolism by the gut microbiota may be a potential target for Nogo-B deficiency to ameliorate NAFLD.

A novel molecular pathway of lipid accumulation in human hepatocytes caused by PFOA and PFOS

Exposed to ubiquitously perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) has been associated with non-alcoholic fatty liver disease (NAFLD), yet the underlying molecular mechanism remains elusive. The extrapolation of empirical studies correlating per- and polyfluoroalkyl substance (PFAS) exposure with NAFLD occurrence to real-life exposure was hindered by the limited availability of mechanistic data at environmentally relevant concentrations. Herein, a novel pathway mediating hepatocyte lipid accumulation by PFOA and PFOS at human-relevant dose (<10 μM) was identified by integrating CRISPR-Cas9 genome screening, concentration-dependent transcriptional assay in HepG2 cell and epidemiological data mining. 1) At genetic level, nudt7 showed the highest enriched potency among 569 NAFLD-related genes, and the transcription of nudt7 was significantly downregulated by PFOA and PFOS exposure (<7 μM). 2) At molecular pathway, upon exposure to ≤10−4 μM PFOA and PFOS, the downregulation of nudt7 transcriptional expression triggered the reduction of Ace-CoA hydrolase activity. 3) At cellular level, increased lipids were measured in HepG2 cells with PFOA and PFOS (<2 μM). Overall, we identified a novel mechanism mediated by transcriptional downregulation of nudt7 gene in hepatocellular lipid increase treated with PFOA and PFOS, which could potentially explain the NAFLD occurrence associated with exposure to PFASs in humans.

Diacylglycerol O-acyltransferase isoforms play a role in peridroplet mitochondrial fatty acid metabolism in bovine liver

Hepatocellular lipid accumulation characterizes fatty liver in dairy cows. Lipid droplets (LD), specialized organelles that store lipids and maintain cellular lipid homeostasis, are responsible for the ectopic storage of lipids associated with several metabolic disorders. In recent years, nonruminant studies have reported that LD-mitochondria interactions play an important role in lipid metabolism. Due to the role of diacylglycerol acyltransferase isoforms (DGAT1 and DGAT2) in LD synthesis, we explored mechanisms of mitochondrial fatty acid transport in ketotic cows using liver biopsies and isolated primary hepatocytes. Compared with healthy cows, cows with fatty liver had massive accumulation of LD and high protein expression of the triglyceride (TAG) synthesis-related enzymes DGAT1 and DGAT2, LD synthesis-related proteins perilipin 2 (PLIN2) and perilipin 5 (PLIN5), and the mitochondrial fragmentation-related proteins dynamin-related protein 1 (DRP1) and fission 1 (FIS1). In contrast, factors associated with fatty acid oxidation, mitochondrial fusion, and mitochondrial electron transport chain complex were lower compared with those in the healthy cows. In addition, transmission electron microscopy revealed significant contacts between LD-mitochondria in liver tissue from cows with fatty liver. Compared with isolated cytoplasmic mitochondria, expression of carnitine palmitoyl transferase 1A (CPT1A) and DRP1 was lower, but mitofusin 2 (MFN2) and mitochondrial electron transport chain complex was greater in isolated peridroplet mitochondria from hepatic tissue of cows with fatty liver. In vitro data indicated that exogenous free fatty acids (FFA) induced hepatocyte LD synthesis and mitochondrial dynamics consistent with in vivo results. Furthermore, DGAT2 inhibitor treatment attenuated the FFA-induced upregulation of PLIN2 and PLIN5 and rescued the impairment of mitochondrial dynamics. Inhibition of DGAT2 also restored mitochondrial membrane potential and reduced hepatocyte reactive oxygen species production. The present in vivo and in vitro results indicated functional differences are present among different types of mitochondria in the liver tissue of dairy cows with ketosis. Activity of DGAT2 may play a key role in maintaining liver mitochondrial function and lipid homeostasis in dairy cows during the transition period.

Fabrication of phenolic loaded spray-dried nanoliposomes stabilized by chitosan and whey protein: Digestive stability, transepithelial transport and bioactivity retention of phenolics

Low bioavailability of phenolic compounds (phenolics) results in low in vivo bioactivity, thus their co-encapsulation could enhance potential health benefits. In this study, reconstitutable nanoliposomes loaded with phenolics varying in solubility were fabricated using spray drying after stabilized by chitosan (CH) or whey protein (WP). The physicochemical properties, biocompatibility, digestive fate, and bioactivity retention of phenolics in different forms were investigated. The surface charge of nanoliposomes (NL) shifted from −18.7 mV to positive due to conjugation with cationic CH (53.1 mV) and WP (14 mV) after spray drying while it was −26.6 mV for only spray-dried phenolics (SDP). Encapsulation efficiency of the tested phenolics ranged between 64.7 % and 95.1 %. Simulated gastrointestinal digestion/Caco-2 cell model was used to estimate the digestive fate of the phenolics yielding up to 3-fold higher bioaccessibility for encapsulated phenolics compared to their native form, combined or individually. However, the cellular uptake or transepithelial transport of phenolics did not differ significantly among formulations, except trans-resveratrol in WP-NL. On the contrary, the suppressive effect of phenolics on fatty acid induced hepatocellular lipid accumulation was strongly dependent on the encapsulation method, no activity was retained by SDP. These findings suggested that reconstitutable nanoliposomes can improve the absorption of phenolics by facilitating their bioaccessibility and thermal and/or processing stability during spray drying.

Fecal microbiota transplantation from female donors restores gut permeability and reduces liver injury and inflammation in middle-aged male mice exposed to alcohol.

Alcohol misuse, binge drinking pattern, and gender-specific effects in the middle-aged population has been clearly underestimated. In the present study, we focused on understanding gender-specific effects of alcohol exposure on the gut-liver axis and the role of gut microbiota in modulating gender-specific responses to alcohol consumption. Fifty-two-week-old female and male C57BL/6 mice were fasted for 12 h, and then administered a single oral dose of ethanol (EtOH) (6 g/kg). Controls were given a single dose of PBS. Animals were sacrificed 8 h later. Alternatively, fecal microbiota transplantation (FMT) was performed in 52-week-old male mice from female donors of the same age. Permeability of the large intestine (colon), gut microbiota, liver injury, and inflammation was thoroughly evaluated in all groups. Middle-aged male mice exposed to EtOH showed a significant increase in gut permeability in the large intestine, evaluated by FITC-dextran assay and ZO-1, OCCLUDIN and MUCIN-2 immuno-staining, compared to PBS-treated animals, whilst female mice of the same age also increased their gut permeability, but displayed a partially maintained intestinal barrier integrity. Moreover, there was a significant up-regulation of TLRs and markers of hepatocellular injury, cell death (AST, TUNEL-positive cells) and lipid accumulation (ORO) in male mice after EtOH exposure. Interestingly, FMT from female donors to male mice reduced gut leakiness, modified gut microbiota composition, ameliorated liver injury and inflammation, TLR activation and the senescence phenotype of middle-aged mice. Our findings highlighted the relevance of gender in middle-aged individuals who are exposed to alcohol in the gut-liver axis. Moreover, our study revealed that gender-specific microbiota transplantation might be a plausible therapy in the management of alcohol-related disorders during aging.

N-glycosylation of SCAP exacerbates hepatocellular inflammation and lipid accumulation via ACSS2-mediated histone H3K27 acetylation.

Sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP) is a widely expressed membrane glycoprotein that acts as an important modulator of lipid metabolism and inflammatory stress. N-glycosylation of SCAP has been suggested to modulate cancer development, but its role in nonalcoholic steatohepatitis (NASH) is poorly understood. In this study, the N-glycosylation of SCAP was analyzed by using sequential trypsin proteolysis and glycosidase treatment. The liver cell lines expressing wild-type and N-glycosylation sites mutated SCAP were constructed to investigate the N-glycosylation role of SCAP in regulating inflammation and lipid accumulation as well as the underlying mechanisms. The hepatic SCAP protein levels were significantly increased in C57BL/6J mice fed with Western diet and sugar water (WD + SW) and diabetic db/db mice, which exhibited typical liver steatosis and inflammation accompanied with hyperglycemia. In vitro, the enhanced N-glycosylation by high glucose increased the protein stability of SCAP and hence increased its total protein levels, whereas the ablation of N-glycosylation significantly decreased SCAP protein stability and alleviated lipid accumulation and inflammation in hepatic cell lines. Mechanistically, SCAP N-glycosylation increased not only the SREBP-1-mediated acetyl-CoA synthetase 2 (ACSS2) transcription but also the AMPK-mediated S659 phosphorylation of ACCS2 protein, causing the enhanced ACSS2 levels in nucleus and hence increasing the histone H3K27 acetylation (H3K27ac), which is a key epigenetic modification associated with NASH. Modulating ACSS2 expression or its location in the nuclear abolished the effects of SCAP N-glycosylation on H3K27ac and lipid accumulation and inflammation. In conclusion, SCAP N-glycosylation aggravates inflammation and lipid accumulation through enhancing ACSS2-mediated H3K27ac in hepatocytes.NEW & NOTEWORTHY N-glycosylation of SCAP exacerbates inflammation and lipid accumulation in hepatocytes through ACSS2-mediated H3K27ac. Our data suggest that SCAP N-glycosylation plays a key role in regulating histone H3K27 acetylation and targeting SCAP N-glycosylation may be a new strategy for treating nonalcoholic steatohepatitis (NASH).

Elevated expression of LCN13 through FXR activation ameliorates hepatocellular lipid accumulation and inflammation

BackgroundLipocalin 13 (LCN13) is a member of the lipocalin family that consists of numerous secretory proteins. LCN13 high-expression has been reported to possess anti-obesity and anti-diabetic effects. Although metabolic dysfunction-associated steatotic liver diseases (MASLD) including metabolic dysfunction-associated steatohepatitis (MASH) are frequently associated with obesity and insulin resistance, the functional role of endogenous LCN13 and the therapeutic effect of LCN13 in MASH and related metabolic deterioration have not been evaluated. MethodsWe employed a methionine-choline deficient diet model and MASH cell models to investigate the role of LCN13 in MASH development. We sought to explore the effects of LCN13 on lipid metabolism and inflammation in hepatocytes under PA/OA exposure using Western blotting, real-time RT-PCR, enzyme-linked immunosorbent assay, hematoxylin and eosin staining, oil red O staining. Using RNA sequencing, chromatin immunoprecipitation assay, and luciferase reporter assays to elucidate whether farnesoid X receptor (FXR) regulates human LCN13 transcription as a transcription factor. ResultsOur study found that LCN13 was down-regulated in MASH patients, MASH mouse and cell models. LCN13 overexpression in hepatocyte cells significantly inhibited lipid accumulation and inflammation in vitro. Conversely, LCN13 downregulation significantly exacerbated lipid accumulation and inflammatory responses in vivo and in vitro. Mechanistically, we provided the first evidence that LCN13 was transcriptionally activated by FXR, representing a novel direct target gene of FXR. And the key promoter region of LCN13 binds to FXR was also elucidated. We further revealed that LCN13 overexpression via FXR activation ameliorates hepatocellular lipid accumulation and inflammation in vivo and in vitro. Furthermore, LCN13-down-regulated mice exhibited aggravated MASH phenotypes, including increased hepatic lipid accumulation and inflammation. ConclusionOur findings provide new insight regarding the protective role of LCN13 in MASH development and suggest an innovative therapeutic strategy for treating MASH or related metabolic disorders.

Portal hypertension in patients with nonalcoholic fatty liver disease: Current knowledge and challenges.

Portal hypertension (PH) has traditionally been observed as a consequence of significant fibrosis and cirrhosis in advanced non-alcoholic fatty liver disease (NAFLD). However, recent studies have provided evidence that PH may develop in earlier stages of NAFLD, suggesting that there are additional pathogenetic mechanisms at work in addition to liver fibrosis. The early development of PH in NAFLD is associated with hepatocellular lipid accumulation and ballooning, leading to the compression of liver sinusoids. External compression and intra-luminal obstacles cause mechanical forces such as strain, shear stress and elevated hydrostatic pressure that in turn activate mechanotransduction pathways, resulting in endothelial dysfunction and the development of fibrosis. The spatial distribution of histological and functional changes in the periportal and perisinusoidal areas of the liver lobule are considered responsible for the pre-sinusoidal component of PH in patients with NAFLD. Thus, current diagnostic methods such as hepatic venous pressure gradient (HVPG) measurement tend to underestimate portal pressure (PP) in NAFLD patients, who might decompensate below the HVPG threshold of 10 mmHg, which is traditionally considered the most relevant indicator of clinically significant portal hypertension (CSPH). This creates further challenges in finding a reliable diagnostic method to stratify the prognostic risk in this population of patients. In theory, the measurement of the portal pressure gradient guided by endoscopic ultrasound might overcome the limitations of HVPG measurement by avoiding the influence of the pre-sinusoidal component, but more investigations are needed to test its clinical utility for this indication. Liver and spleen stiffness measurement in combination with platelet count is currently the best-validated non-invasive approach for diagnosing CSPH and varices needing treatment. Lifestyle change remains the cornerstone of the treatment of PH in NAFLD, together with correcting the components of metabolic syndrome, using nonselective beta blockers, whereas emerging candidate drugs require more robust confirmation from clinical trials.

Dietary supplementation of pterostilbene, a major component in small berries, prevents alcohol-induced liver injury associated with lipid accumulation and inflammation.

Pterostilbene (PTE), a natural stilbene found in small berries, exhibits multiple pharmacological activities, particularly antioxidant and anti-inflammatory activities. This study explores the dietary supplementation of PTE to ameliorate acute and chronic alcohol-associated liver disease (ALD). C57BL/6 mice were administrated with PTE and subjected to acute or chronic alcohol stimulation. They were intragastrically administered with alcohol (5 g kg-1, 3 times per 24 h) to induce acute alcohol liver injury or fed a Lieber-DeCarli liquid diet containing 5% ethanol for 4 weeks and a single binge to induce chronic alcoholic liver injury. In the acute ethanol model, PTE decreased the serum transaminase and triglyceride (TG) levels and ameliorated lipid droplet accumulation. PTE ameliorated acute ethanol-induced hepatic steatosis by inhibiting the expression of SREBP1 and its target genes and up-regulating PPARα expression. PTE could reverse the inflammatory response by inhibiting NLRP3 activation, inflammatory factor secretion, and macrophage recruitment caused by acute ethanol exposure. PTE could synergistically activate the SIRT1-AMPK and LXR/FXR axis in mice with acute ethanol exposure. In the chronic-binge ethanol feeding model, PTE also decreased serum transaminase and TG levels and ameliorated hepatocellular ballooning, macrovesicular steatosis, lipid accumulation and inflammation. Chronic-binge ethanol feeding could induce extracellular matrix dysfunction with an increase in α-SMA, collagen I and TIMP-1 expression, which was decreased by PTE. PTE increased SIRT1 expression and AMPK phosphorylation and activated the LXRs/FXR axis, which could be reduced by chronic-binge ethanol feeding. PTE could prevent liver injury caused by alcohol regardless of acute or chronic exposure. These results suggest that PTE can be utilized as a dietary health supplement to avoid ALD and promote health and quality of life.

Evaluation of Hepatoprotective Potential and oxidative stress of Allium ascalonicum L. methanol leaf extract on liver of Albino rats

Background: For decades, the leaves of Allium ascalonicum (commonly known as Alubosa elewe) from the Liliaceae family have been widely used in Nigeria for managing disorders. Despite its extensive use in traditional medicine, there is no scientific validation to support this traditional use. Aim: This study aimed to evaluate the hepatoprotective effect of Allium ascalonicum methanol extract (A. AMLE) in albino rats with acetaminophen-induced liver injury. Methods: Standard procedures were employed to conduct a phytochemical screening of A. AMLE. The hepatoprotective effect of A. AMLE was assessed using biomarkers of hepatocellular indices, oxidative stress, and lipid peroxidation. Albino rats were administered distilled water or A. AMLE at doses of 100, 200, or 400 mg/kg body weight, respectively, for seven days. The treatment groups were challenged with 300 mg/kg body weight of acetaminophen on the sixth day. Results: The phytochemical screening revealed the presence of flavonoids, saponins, anthraquinones, alkaloids, and tannins in A. AMLE. Oral administration of A. AMLE significantly (p &lt; 0.05) attenuated acetaminophen-induced alterations in serum alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, albumin, and total bilirubin levels. Additionally, the acetaminophen-mediated decrease in the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase were significantly ameliorated in the liver of albino rats. Elevated levels of malondialdehyde, conjugated dienes, lipid hydroperoxides, tumor necrosis factor-α, and interleukins-6 and -8 were significantly reduced by A. AMLE. Conclusion: This study scientifically validates the traditional use of Allium ascalonicum leaves for liver disorder management by demonstrating that its methanol extract mitigates acetaminophen-induced hepatotoxicity through enhanced antioxidant enzyme activity, highlighting its potential as a natural hepatoprotective agent and paving the way for further research and clinical application.

Advances in Targeted Drug Resistance Associated with Dysregulation of Lipid Metabolism in Hepatocellular Carcinoma.

Hepatocellular carcinoma is the prevailing malignant neoplasm affecting the liver, often diagnosed at an advanced stage and associated with an unfavorable overall prognosis. Sorafenib and Lenvatinib have emerged as first-line therapeutic drugs for advanced hepatocellular carcinoma, improving the prognosis for these patients. Nevertheless, the issue of tyrosine kinase inhibitor (TKI) resistance poses a substantial obstacle in the management of advanced hepatocellular carcinoma. The pathogenesis and advancement of hepatocellular carcinoma exhibit a close association with metabolic reprogramming, yet the attention given to lipid metabolism dysregulation in hepatocellular carcinoma development remains relatively restricted. This review summarizes the potential significance and research progress of lipid metabolism dysfunction in Sorafenib and Lenvatinib resistance in hepatocellular carcinoma. Targeting hepatocellular carcinoma lipid metabolism holds promising potential as an effective strategy to overcome hepatocellular carcinoma drug resistance in the future.

Reduced Insulin Clearance Differently Relates to Increased Liver Lipid Content and Worse Glycemic Control in Recent-Onset Type 2 and Type 1 Diabetes.

Diabetes may feature impaired insulin kinetics, which could be aggravated by altered hepatic metabolism and glycemic control. Thus, we examined insulin clearance and its possible determinants in individuals with recent-onset diabetes. Participants of the German Diabetes Study (GDS) with type 1 diabetes (T1D) (n = 306), type 2 diabetes (T2D) (n = 489), or normal glucose tolerance (control [CON]) (n = 167) underwent hyperinsulinemic-euglycemic clamps for assessment of whole-body insulin sensitivity (M value) and insulin clearance (ICCLAMP). Insulin clearance rates were further calculated during intravenous glucose tolerance tests (ICIVGTT) and mixed-meal tests (ICMMT). Hepatocellular lipid content (HCL) was quantified with 1H-MRS. Both T1D and T2D groups had lower ICCLAMP (0.12 ± 0.07 and 0.21 ± 0.06 vs. 0.28 ± 0.14 arbitrary units [a.u.], respectively, all P < 0.05) and ICMMT (0.71 ± 0.35 and 0.99 ± 0.33 vs. 1.20 ± 0.36 a.u., all P < 0.05) than CON. In T1D, ICCLAMP, ICIVGTT, and ICMMT correlated negatively with HbA1c (all P < 0.05). M value correlated positively with ICIVGTT in CON and T2D (r = 0.199 and r = 0.178, P < 0.05) and with ICMMT in CON (r = 0.176, P < 0.05). HCL negatively associated with ICIVGTT and ICMMT in T2D (r = -0.005 and r = -0.037) and CON (r = -0.127 and r = -0.058, all P < 0.05). In line, T2D or CON subjects with steatosis featured lower ICMMT than those without steatosis (both P < 0.05). Insulin clearance is reduced in both T1D and T2D within the first year after diagnosis but correlates negatively with liver lipid content rather in T2D. Moreover, insulin clearance differently associates with glycemic control and insulin sensitivity in each diabetes type, which may suggest specific mechanisms affecting insulin kinetics.

NAFLD-Related HCC: Focus on the Latest Relevant Preclinical Models.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and one of the deadliest cancers worldwide. Despite extensive research, the biological mechanisms underlying HCC's development and progression remain only partially understood. Chronic overeating and/or sedentary-lifestyle-associated obesity, which promote Non-Alcoholic Fatty Liver Disease (NAFLD), have recently emerged as worrying risk factors for HCC. NAFLD is characterized by excessive hepatocellular lipid accumulation (steatosis) and affects one quarter of the world's population. Steatosis progresses in the more severe inflammatory form, Non-Alcoholic Steatohepatitis (NASH), potentially leading to HCC. The incidence of NASH is expected to increase by up to 56% over the next 10 years. Better diagnoses and the establishment of effective treatments for NAFLD and HCC will require improvements in our understanding of the fundamental mechanisms of the disease's development. This review describes the pathogenesis of NAFLD and the mechanisms underlying the transition from NAFL/NASH to HCC. We also discuss a selection of appropriate preclinical models of NAFLD for research, from cellular models such as liver-on-a-chip models to in vivo models, focusing particularly on mouse models of dietary NAFLD-HCC.

Genipin protects against acute liver injury by abrogating ferroptosis via modification of GPX4 and ALOX15-launched lipid peroxidation in mice.

It is essential to further characterize liver injury aimed at developing novel therapeutic approaches. This study investigated the mechanistic basis of genipin against carbon tetrachloride (CCl4)-triggered acute liver injury concerning ferroptosis, a novel discovered modality of regulated cell death. All experiments were performed using hepatotoxic models upon CCl4 exposure in mice and human hepatocytes in vitro. Immunohistochemistry, immunoblotting, molecular docking, RNA-sequencing and ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) were conducted. CCl4 intoxication was manifested with lipid peroxidation-dictated ferroptotic cell death, together with changes in a cascade of ferroptosis-associated events and several regulatory pathways. Both the administration of genipin and ferrostatin-1 (Fer-1) significantly prevented this hepatotoxicity in response to CCl4 intoxication via upregulating GPX4 and xCT (i.e., critical regulators of ferroptosis). RNA-sequencing unraveled that arachidonic acid metabolism was considerably influenced upon genipin treatment. Accordingly, genipin treatment attenuated arachidonate 15-lipoxygenase (ALOX15)-launched lipid peroxidation in terms of UHPLC-MS/MS analysis and inflammation. In vitro, genipin supplementation rescued erastin-induced hepatocellular inviability and lipid ROS accumulation. The siRNA knockdown of GPX4 partially abrogated the protective effects of genipin on erastin-induced cytotoxicity, whereas the cytotoxicity was less severe in the presence of diminished ALOX15 expression in L-O2 cells. In conclusion, our findings uncovered that genipin treatment protects against CCl4-triggered acute liver injury by abrogating hepatocyte ferroptosis, wherein the pharmacological modification of dysregulated GPX4 and ALOX15-launched lipid peroxidation was responsible for underlying medicinal effects as molecular basis.

1566-P: The TM6SF2 rs58542926 Polymorphism Dissociates Hepatocellular Lipids from Insulin Resistance in Recent-Onset Type 2 Diabetes

Increased hepatocellular lipid content (HCL) is generally linked to insulin resistance, which contributes to greater risk of type 2 diabetes and cardiovascular complications. Conversely, a single-nucleotide polymorphism (TM6SF2EK; rs58542926) in the transmembrane 6 superfamily member 2 gene has been associated with nonalcoholic fatty liver disease (NAFLD), but lower cardiovascular risk. Thus, this case-control study tested the role of this polymorphism for tissue-specific insulin sensitivity during the early course of diabetes. Males with recent-onset type 2 diabetes with (TM6SF2EK: n=16) or without (TM6SF2EE: n=16) the heterozygous TM6SF2 polymorphism of similar age and BMI, underwent Botnia-clamps with [6,6-2H2]glucose to measure whole-body, hepatic and adipose tissue insulin sensitivity. HCL and liver fibrosis were assessed with 1H-magnetic resonance spectroscopy and non-invasive tests (FIB4, APRI, AST/ALT), respectively. A subset of both groups (n=24) was re-evaluated after 5 years. Despite doubled HCL, TM6SF2EK had similar hepatic and adipose tissue insulin sensitivity and even 27% higher whole-body insulin sensitivity than TM6SF2EE. The novel diabetes endotypes were equally distributed among both groups. After 5 years, whole-body insulin sensitivity, HCL and liver fibrosis indices were similar, while adipose tissue insulin sensitivity decreased by 87% and 55% both in TM6SF2EK and TM6SF2EE and circulating triacylglycerol increased in TM6SF2EE only. The TM6SF2 gene polymorphism rs58542926 dissociates ectopic fat content from insulin resistance in recent-onset type 2 diabetes, which is however attenuated by disease duration. This suggests that diabetes-related metabolic alterations dominate over the effects of the TM6SF2 gene polymorphism during the early course of diabetes and NAFLD. Disclosure K.Bódis: None. R.Guthoff: Other Relationship; Alimera, Bayer Inc., Novartis, Allergan. V.Schrauwen-hinderling: None. H.Al-hasani: None. V.Burkart: None. J.Szendroedi: None. R.Wagner: Advisory Panel; Daiichi Sankyo, Speaker's Bureau; Novo Nordisk, Sanofi. D.F.Markgraf: Employee; Boehringer Ingelheim Pharma GmbH&amp;Co.KG. M.Roden: Advisory Panel; Eli Lilly and Company, Consultant; TARGET PharmaSolutions, Inc., Research Support; Boehringer-Ingelheim, Novo Nordisk, Novartis, Sanofi. M.Bombrich: None. M.Schön: None. B.Knebel: None. O.P.Zaharia: None. G.J.Bönhof: None. Y.Karusheva: None. Y.Kupriyanova: None. J.Kotzka: None.

1573-P: Association of Thyroid Hormone Levels with NAFLD in Recent-Onset Diabetes

Nonalcoholic fatty liver disease (NAFLD) is a growing health concern associated with obesity and type 2 diabetes (T2D). Thyroid hormones are important regulators of lipid homeostasis. Indeed, people with hypothyroidism are at greater risk for NAFLD and it has been suggested that humans with T2D are more likely to develop hypothyroidism. However, little is known about the relationship of thyroid function with NAFLD in type 1 diabetes (T1D) and T2D. We hypothesized that (i) low free thyroxin (fT4) and high thyroid-stimulating hormone (TSH) levels are associated with increased hepatocellular lipid content (HCL) and (ii) that fT4 and TSH can identify persons at high-risk for hepatic steatosis in people with recent-onset diabetes. We examined people with T1D (n=358) or T2D (n=596) and 175 healthy participants of the German Diabetes Study (GDS). First, validation of the fatty liver index (FLI) against quantification of HCL by 1H-magnetic resonance spectroscopy revealed a close correlation (ß=0.715, p&amp;lt;0.001; n=446). Second, FLI negatively correlated with fT4 in males (ß=−0.139, p&amp;lt;0.01), but not in females with T2D (ß=−0.086, p=0.26). Likewise, TSH associated positively with FLI in males (ß=0.116, p&amp;lt;0.05), but not in females with T2D (ß=−0.057, p=0.45). TSH and FLI were differently associated between males and females before (p&amp;lt;0.05), but not after (p=0.82) adjustment for BMI. Finally, fT4 had a low diagnostic precision for steatosis (by FLI) as derived from the respective area under the receiver operating curve (0.57, 95% CI [0.53;0.62]; p&amp;lt;0.001) in T2D and was not significant in other groups. TSH had no diagnostic precision for steatosis in any groups. In conclusion, FLI can be used as a surrogate measure of HCL in recent-onset diabetes. The correlation of FLI with lower thyroid function in male T2D suggests a sex-specific interaction between thyroid and liver lipid metabolism, which is mainly driven by body mass. Both, fT4 and TSH offer no relevant efficacy to detect steatosis at least in recent-onset diabetes. Disclosure N. Saatmann: None. M. Schön: None. O.P. Zaharia: None. M. Huttasch: None. K. Strassburger: None. S. Trenkamp: None. Y. Kupriyanova: None. V. Schrauwen-Hinderling: None. S. Kahl: None. V. Burkart: None. R. Wagner: Speaker's Bureau; Novo Nordisk, Sanofi. Advisory Panel; Daiichi Sankyo. M. Roden: Advisory Panel; Eli Lilly and Company. Research Support; Boehringer-Ingelheim, Novo Nordisk, Novartis. Consultant; TARGET PharmaSolutions, Inc. Research Support; Sanofi.