Development Of Fatty Liver Disease Research Articles

Muscle Quality as a Potential Diagnostic Marker of Advanced Liver Fibrosis in Patients with Non-alcoholic Fatty Liver Disease.

Muscle-liver crosstalk plays an important role in the development and progression of non-alcoholic fatty liver disease (NAFLD). The measurement of muscle echo-intensity during ultrasonography is a real-time, non-invasive method of assessing muscle quality. In this retrospective study, we investigated the significance of poor muscle quality (namely, a greater mass of non-contractile tissue, including intramuscular fat) as a risk factor for advanced liver fibrosis and considered whether it may represent a useful tool for the diagnosis of advanced liver fibrosis. We analyzed data from 307 patients with NAFLD (143 men and 164 women) who visited the University of Tsukuba Hospital between 2017 and 2022. The patients were stratified into the following tertiles of muscle quality according to their muscle echo-intensity on ultrasonography: modest (84.1 A.U.), intermediate (97.4 A.U.), and poor (113.6 A.U.). We then investigated the relationships between muscle quality and risk factors for advanced liver fibrosis and calculated appropriate cutoff values. Patients with poor muscle quality showed a significant, 7.6-fold greater risk of liver fibrosis compared to those with modest muscle quality. Receiver operating characteristic curve analysis showed that muscle quality assessment was as accurate as the Fibrosis-4 index and NAFLD fibrosis score in screening for liver fibrosis and superior to the assessment of muscle quantity and strength, respectively. Importantly, a muscle echo-intensity of ≥92.4 A.U. may represent a useful marker of advanced liver fibrosis. Muscle quality may represent a useful means of identifying advanced liver fibrosis, and its assessment may become a useful screening tool in daily practice.

Association between biological aging and the risk of mortality in individuals with non-alcoholic fatty liver disease: A prospective cohort study

BackgroundThe biological process of aging plays an important role in nonalcoholic fatty liver disease (NAFLD) development. However, epidemiological evidence about the association of biological aging with mortality risk among people with NAFLD is limited. MethodsA total of 2199 participants with NAFLD from the National Health and Nutrition Examination Surveys (NHANES) III were included. The outcomes were all-cause and cause-specific (cardiovascular disease [CVD], cancer, and diabetes) mortality. We computed three BA measures, the Klemera-Doubal method (KDM) age, Phenotypic age, and homeostatic dysregulation (HD), by using 18 age-associated clinical biomarkers, and assessed their associations with mortality risk using Cox proportional hazards (CPH) models. ResultsAfter a median follow-up of 16 years, a total of 1077 deaths occurred. People with NAFLD who died during follow-up period exhibited higher baseline biological age (BA) and biological age accelerations (BAAs). The multivariate-adjusted CPH suggested that a one-standard deviation (SD) increase in KDM age acceleration, Phenotypic age acceleration, or HD was associated with a 3 %, 7 %, or 39 % elevated risk of all-cause mortality, respectively. The results of age-varying HRs showed that the associations of KDM age accelerations (AAs) and Phenotypic AAs with all-cause mortality appeared to be stronger in people with NAFLD younger than 45 years. ConclusionsBiological aging was positively associated with both all-cause and cause-specific mortality among people with NAFLD, particularly among younger individuals.

Impact of Transgenerational Nutrition on Nonalcoholic Fatty Liver Disease Development: Interplay between Gut Microbiota, Epigenetics and Immunity.

Nonalcoholic fatty liver disease (NAFLD) has emerged as the most prevalent pediatric liver disorder, primarily attributed to dietary shifts in recent years. NAFLD is characterized by the accumulation of lipid species in hepatocytes, leading to liver inflammation that can progress to steatohepatitis, fibrosis, and cirrhosis. Risk factors contributing to NAFLD encompass genetic variations and metabolic disorders such as obesity, diabetes, and insulin resistance. Moreover, transgenerational influences, resulting in an imbalance of gut microbial composition, epigenetic modifications, and dysregulated hepatic immune responses in offspring, play a pivotal role in pediatric NAFLD development. Maternal nutrition shapes the profile of microbiota-derived metabolites in offspring, exerting significant influence on immune system regulation and the development of metabolic syndrome in offspring. In this review, we summarize recent evidence elucidating the intricate interplay between gut microbiota, epigenetics, and immunity in fetuses exposed to maternal nutrition, and its impact on the onset of NAFLD in offspring. Furthermore, potential therapeutic strategies targeting this network are also discussed.

Exploration and Validation of Ferroptosis-Associated Genes in ADAR1 Deletion-Induced NAFLD through RNA-seq Analysis

BackgroundFerroptosis, characterized by excessive iron ions and lipid peroxides accumulation, contributes to Nonalcoholic Fatty Liver Disease (NAFLD) development. The role of ADAR1, crucial for lipid metabolism and immune regulation, in ferroptosis-related NAFLD remains unexplored. MethodsIn this study, we analyzed the expression of ADAR1 in NAFLD patients using the GSE66676 database. Subsequently, We investigated the effects of ADAR1 knockdown on mitochondrial membrane potential (MMP), Fe2+ levels, oxidation products, and ferroptosis in NAFLD cells through in vitro and in vivo experiments. Additionally, RNA-seq analysis was performed following ADAR1 depletion in an NAFLD cell model. Overlapping and ferroptosis-related genes were identified using a Venn diagram, while Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted as well. Furthermore, a protein-protein interaction (PPI) network was constructed to identify hub genes associated with ferroptosis. ResultsWe found the expression level of ADAR1 was downregulated in NAFLD patients and 22 ferroptosis-associated genes were differentially expressed in a NAFLD cell model upon ADAR1 knockdown. Based on PPI network, we identified NOS2, PTGS2, NOX4, ALB, IL6, and CCL5 as the central genes related to ferroptosis. ADAR1 deletion-related NAFLD was found to be involved in the ferroptosis signaling pathway. NOS2, PTGS2, ALB, and IL6 can serve as potential biomarkers. These findings offer new insights and expanded targets for NAFLD prevention and treatment. ConclusionThese findings provide new strategies and potential targets for preventing and treating NAFLD. NOS2, PTGS2, ALB, and IL6 may serve as biomarkers for ADAR1 deletion-related NAFLD, which could help for developing its new diagnostic and therapeutic strategies.

A 30-color spectral flow cytometry panel for comprehensive analysis of immune cell composition and macrophage subsets in mouse metabolic organs.

Obesity-induced chronic low-grade inflammation, also known as metaflammation, results from alterations of the immune response in metabolic organs and contributes to the development of fatty liver diseases and type 2 diabetes. The diversity of tissue-resident leukocytes involved in these metabolic dysfunctions warrants an in-depth immunophenotyping in order to elucidate disease etiology. Here, we present a 30-color, full spectrum flow cytometry panel, designed to (i) identify the major innate and adaptive immune cell subsets in murine liver and white adipose tissues and (ii) discriminate various tissue-specific myeloid subsets known to contribute to the development of metabolic dysfunctions. This panel notably allows for distinguishing embryonically-derived liver-resident Kupffer cells from newly recruited monocyte-derived macrophages and KCs. Furthermore, several adipose tissue macrophage (ATM) subsets, including perivascular macrophages, lipid-associated macrophages, and pro-inflammatory CD11c+ ATMs, can also be identified. Finally, the panel includes cell-surface markers that have been associated with metabolic activation of different macrophage and dendritic cell subsets. Altogether, our spectral flow cytometry panel allows for an extensive immunophenotyping of murine metabolic tissues, with a particular focus on metabolically-relevant myeloid cell subsets, and can easily be adjusted to include various new markers if needed.

Impact of alcohol consumption on metabolic dysfunction-associated fatty liver disease development and remission: A longitudinal cohort study.

The influence of alcohol intake on metabolic dysfunction-associated fatty liver disease (MAFLD) development and remission remains unclear; thus, we aimed to investigate their longitudinal associations. This observational cohort study included 6349 patients who underwent more than two health check-ups over >2 years between April 2013 and March 2021. Generalized estimation equations were used to analyse the longitudinal associations between changes in alcohol intake and MAFLD according to repeated measures at baseline and the most recent stage. The MAFLD development and remission rates were 20.4 and 5.1 and 9.1 and 4.7% in men and women, respectively. Although alcohol consumption was not a significant factor for MAFLD development, consuming 0.1-69.9 g/week (odds ratio [OR]: 0.672, 95% confidence interval [CI]: 0.469-0.964, p < .05) and ≥280 g/week were significant factors for MAFLD development in males (OR: 1.796, 95% CI: 1.009-3.196, p < .05) and females (OR: 16.74, 95% CI: 3.877-72.24, p < .001). Regardless of quantity and frequency, alcohol consumption was not a significant factor for MAFLD remission. Several noninvasive liver fibrosis scores were significantly associated with alcohol intake quantity and frequency in males with MAFLD development and remission (p < .05). The nonalcoholic fatty liver disease fibrosis score differed significantly between males with and without reduced alcohol intake (p < .05) who showed MAFLD remission. Although the influence of alcohol intake on MAFLD development and remission differed, alcohol consumption was not beneficial for MAFLD remission in either sex. Alcohol intake reduction or cessation is recommended to prevent liver fibrosis, even in those who achieve MAFLD remission.

Lactiplantibacillus plantarum ZDY2013 Inhibits the Development of Non-Alcoholic Fatty Liver Disease by Regulating the Intestinal Microbiota and Modulating the PI3K/Akt Pathway.

Non-alcoholic fatty liver disease (NAFLD) is a common chronic hepatic condition whose impact on human health is increasingly significant. The imbalance of the gut microbiome, linked to insulin resistance, heightened intestinal permeability, and pro-inflammatory reactions, may be the linchpin in the development of NAFLD. In our research, the impact of Lactiplantibacillus plantarum ZDY2013 administration for 12 weeks on gut microbiota dysbiosis induced by a high-fat, high-fructose, high-cholesterol (FHHC) diet in male C57BL/6n mice was investigated. Research results presented that the intervention of L. plantarum ZDY2013 in mice fed with the FHHC diet could restore their liver function and regulate oxidative stress. Compared to mice in the model group, the intervention of L. plantarum ZDY2013 significantly regulated the gut microbiota, inhibited the LPS/NF-κB pathway, and led to a lower level of colonic inflammation in the mice administered with L. plantarum ZDY2013. It also improved insulin resistance to regulate the PI3K/Akt pathway and lipid metabolism, thereby resulting in reduced fat accumulation in the liver. The above results suggest that the intervention of L. plantarum ZDY2013 can hinder the progression of diet-induced NAFLD by reducing inflammation to regulate the PI3K/Akt pathway and regulating gut microbiota disturbance.

Abstract 2169: Dietary inflammatory potential and mortality among patients with MAFLD

Abstract Background: Inflammation is important in metabolic dysfunction-associated fatty liver disease (MAFLD) development and progression. However, evidence regarding the influence of dietary inflammatory potential and mortality among people with MAFLD is rare. This study aimed to elucidate the association of the energy-density dietary inflammatory index (E-DII) with all-cause and cause-specific mortality among MAFLD patients. Methods: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) (1988-1994, 1999-2010). MAFLD was defined as the evidence of hepatic steatosis with ≥1 of the following: type 2 diabetes (T2DM), overweight/obesity (OW, BMI ≥ 25 kg/m2), or lean metabolic dysregulation (MD). Dietary intake was assessed through 24-hour dietary recalls. E-DII scores and component intakes were divided into tertiles, with T1 as the reference. Through linkage to National Death Index by December 31, 2019, mortality from all cause, cardiovascular disease (CVD), and cancer were identified. Multivariable Cox proportional hazards regression model and restricted cubic splines (RCS) were used to analyze the association between dietary inflammatory potential and mortality among MAFLD and its subtypes patients. Results: A total of 6537 MAFLD patients were included in the present analysis. During the median follow-up of 16.8 years, 2281 total deaths (534 cancer-related, 750 CVD-related) were documented. Compared to high dietary inflammatory potential, low dietary inflammatory potential presented a inverse association with all-cause mortality risk in MAFLD patients (HR T2 vs. T1 = 0.83, 95% CI = 0.72-0.95, HR T3 vs. T1 = 0.88, 95% CI = 0.76-1.01, P trend = 0.092) and OW subtype patients (HR T2 vs. T1 = 0.77, 95% CI = 0.63-0.93, HR T3 vs. T1 = 0.76, 95% CI = 0.63-0.92, P trend = 0.009). No significant benefit was observed among T2DM and MD subtype patients. Further component analysis found that eicosapentaenoic acid (EPA) (HR = 0.74, 95% CI = 0.66-0.83), docosapentaenoic acid (DPA) (HR = 0.72, 95% CI = 0.65-0.80), docosahexaenoic acid (DHA) (HR = 0.85, 95% CI = 0.65-0.80), and linoleic acid (HR = 0.86, 95% CI = 0.79-0.94) were linked with reduced cancer mortality risk in MAFLD patients. Further RCS analyses found that the effect pattern of EPA, DPA, and DHA on both all-cause and cause-specific mortality was presented as “J shaped” (P non-linear &amp;lt; 0.05). Similar results were observed for all-cause and CVD mortality among both MAFLD and OW subtype patients. When excluding participants who died within five years, consistent results were presented. Conclusions: The findings of this study suggest that keep low-inflammatory dietary pattern, especially appropriate level of PUFAs component (EPA, DPA, and DHA) intake were associated with a lower risk of cancer mortality in MAFLD patients. These findings may inform future public health guidelines regarding specific dietary consumption, and liver-related health promotion. Citation Format: Zhangyan Lyu, Yacong Zhang, Wenxuan Li, Guoijn Si, Kexin Chen. Dietary inflammatory potential and mortality among patients with MAFLD [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2169.

Hypercaloric low-carbohydrate high-fat diet protects against the development of nonalcoholic fatty liver disease in obese mice in contrast to isocaloric Western diet.

Obesity and metabolic complications, such as type 2 diabetes and nonalcoholic fatty liver disease (NAFLD), are one of the greatest public health challenges of the 21st century. The major role of high sugar and carbohydrate consumption rather than caloric intake in obesity and NAFLD pathophysiology remains a subject of debate. A low-carbohydrate but high-fat diet (LCHFD) has shown promising results in obesity management, but its effects in preventing NAFLD need to be detailed. This study aims to compare the effects of a LCHFD with a high-fat high-sugar obesogenic Western diet (WD) on the progression of obesity, type 2 diabetes, and nonalcoholic fatty liver disease. Male C57BL/6J mice were initially fed a WD for 10 weeks. Subsequently, they were either switched to a LCHFD or maintained on the WD for an additional 6 weeks. Hepatic effects of the diet were explored by histological staining and RT-qPCR. After the initial 10 weeks WD feeding, LCHF diet demonstrated effectiveness in halting weight gain, maintaining a normal glucose tolerance and insulin levels, in comparison to the WD-fed mice, which developed obesity, glucose intolerance, increased insulin levels and induced NAFLD. In the liver, LCHFD mitigated the accumulation of hepatic triglycerides and the increase in Fasn relative gene expression compared to the WD mice. Beneficial effects of the LCHFD occurred despite a similar calorie intake compared to the WD mice. Our results emphasize the negative impact of a high sugar/carbohydrate and lipid association for obesity progression and NAFLD development. LCHFD has shown beneficial effects for NAFLD management, notably improving weight management, and maintaining a normal glucose tolerance and liver health.

Multi-omics analysis of TLCD1 as a promising biomarker in pan-cancer.

Background: The TLC Domain Containing 1 (TLCD1) protein, a key regulator of phosphatidylethanolamine (PE) composition, is distributed across several cellular membranes, including mitochondrial plasma membranes. Existing research has revealed the impact of TLCD1 on the development of non-alcoholic fatty liver disease. However, there remains a gap in comprehensive pan-cancer analyses of TLCD1, and the precise role of TLCD1 in cancer patient prognosis and immunological responses remains elusive. This study aims to provide a comprehensive visualization of the prognostic landscape associated with TLCD1 across a spectrum of cancers, while shedding light on the potential links between TLCD1 expression within the tumor microenvironment and immune infiltration characteristics. Methods: TLCD1 expression data were obtained from GTEx, TCGA, and HPA data repositories. Multiple databases including TIMER, HPA, TISIDB, cBioPortal, GEPIA2, STRING, KEGG, GO, and CancerSEA were used to investigate the expression pattern, diagnostic and prognostic significance, mutation status, functional analysis, and functional status of TLCD1. In addition, we evaluated the relationship between TLCD1 expression and immune infiltration, tumor mutational burden (TMB), microsatellite instability (MSI), and immune-related genes in pan-cancer. Furthermore, the association of TLCD1 with drug sensitivity was analyzed using the CellMiner database. Results: We found that TLCD1 is generally highly expressed in pan-cancers and is significantly associated with the staging and prognosis of various cancers. Furthermore, our results also showed that TLCD1 was significantly associated with immune cell infiltration and immune regulatory factor expression. Using CellMiner database analysis, we then found a strong correlation between TLCD1 expression and sensitivity to anticancer drugs, indicating its potential as a therapeutic target. The most exciting finding is that high TLCD1 expression is associated with worse survival and prognosis in GBM and SKCM patients receiving anti-PD1 therapy. These findings highlight the potential of TLCD1 as a predictive biomarker for response to immunotherapy. Conclusion: TLCD1 plays a role in the regulation of immune infiltration and affects the prognosis of patients with various cancers. It serves as both a prognostic and immunologic biomarker in human cancer.

Altered lipid metabolism and the development of metabolic-associated fatty liver disease.

An increasing amount of research has underscored the significant role of lipoproteins in the pathogenesis of metabolic-associated fatty liver disease (MAFLD). This comprehensive review examines the intricate relationship between lipoprotein abnormalities and the development of MAFLD. Atherogenic dyslipidemia seen in insulin resistance states play a significant role in initiating and exacerbating hepatic lipid accumulation. There are also specific genetic factors (PNPLA3, TM6SF2, MBOAT7, HSD17B13, GCKR-P446L) and transcription factors (SREBP-2, FXR, and LXR9) that increase susceptibility to both lipoprotein disorders and MAFLD. Most monogenic primary lipid disorders do not cause hepatic steatosis unless accompanied by metabolic stress. Hepatic steatosis occurs in the presence of secondary systemic metabolic stress in conjunction with predisposing environmental factors that lead to insulin resistance. Identifying specific aberrant lipoprotein metabolic factors promoting hepatic fat accumulation and subsequently exacerbating steatohepatitis will shed light on potential targets for therapeutic interventions. The clinical implications of interconnection between genetic factors and an insulin resistant environment that predisposes MAFLD is many fold. Potential therapeutic strategies in preventing or mitigating MAFLD progression include lifestyle modifications, pharmacological interventions, and emerging therapies targeting aberrant lipoprotein metabolism.

Research Progress on Lipophagy-Mediated Exercise Intervention in Non-Alcoholic Fatty Liver Disease.

Lipophagy is a cellular pathway targeting the lysosomal degradation of lipid droplets, playing a role in promoting lipid turnover and renewal. Abnormal lipophagy processes can lead to the occurrence and development of non-alcoholic fatty liver disease (NAFLD), characterized by the deposition of lipid droplets (LDs) in the liver. The importance of exercise training in preventing and improving NAFLD has been well-established, but the exact mechanisms remain unclear. Recent research findings suggest that lipophagy may serve as a crucial hub for liver lipid turnover under exercise conditions. Exercise may alleviate hepatic lipid accumulation and mitigate inflammatory responses and fibrosis through lipophagy, thereby improving the onset and progression of NAFLD.

Bis(2-ethylhexyl)-tetrabromophthalate Poses a Higher Exposure Risk and Induces Gender-Specific Metabolic Disruptions in Zebrafish Liver.

Bis(2-ethylhexyl)-tetrabromophthalate (TBPH), a typical novel brominated flame retardant, has been ubiquitously identified in various environmental and biotic media. Consequently, there is an urgent need for precise risk assessment based on a comprehensive understanding of internal exposure and the corresponding toxic effects on specific tissues. In this study, we first investigated the toxicokinetic characteristics of TBPH in different tissues using the classical pseudo-first-order toxicokinetic model. We found that TBPH was prone to accumulate in the liver rather than in the gonad, brain, and muscle of both female and male zebrafish, highlighting a higher internal exposure risk for the liver. Furthermore, long-term exposure to TBPH at environmentally relevant concentrations led to increased visceral fat accumulation, signaling potential abnormal liver function. Hepatic transcriptome analysis predominantly implicated glycolipid metabolism pathways. However, alterations in the profile of associated genes and biochemical indicators revealed gender-specific responses following TBPH exposure. Besides, histopathological observations as well as the inflammatory response in the liver confirmed the development of nonalcoholic fatty liver disease, particularly in male zebrafish. Altogether, our findings highlight a higher internal exposure risk for the liver, enhancing our understanding of the gender-specific metabolic-disrupting potential associated with TBPH exposure.

Emerging roles of RNA-binding proteins in fatty liver disease.

A rampant and urgent global health issue of the 21st century is the emergence and progression of fatty liver disease (FLD), including alcoholic fatty liver disease and the more heterogenous metabolism-associated (or non-alcoholic) fatty liver disease (MAFLD/NAFLD) phenotypes. These conditions manifest as disease spectra, progressing from benign hepatic steatosis to symptomatic steatohepatitis, cirrhosis, and, ultimately, hepatocellular carcinoma. With numerous intricately regulated molecular pathways implicated in its pathophysiology, recent data have emphasized the critical roles of RNA-binding proteins (RBPs) in the onset and development of FLD. They regulate gene transcription and post-transcriptional processes, including pre-mRNA splicing, capping, and polyadenylation, as well as mature mRNA transport, stability, and translation. RBP dysfunction at every point along the mRNA life cycle has been associated with altered lipid metabolism and cellular stress response, resulting in hepatic inflammation and fibrosis. Here, we discuss the current understanding of the role of RBPs in the post-transcriptional processes associated with FLD and highlight the possible and emerging therapeutic strategies leveraging RBP function for FLD treatment. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Oral Safety Evaluation of the Aqueous Fruit Extract of Annona Muricata in Wistar Rats

Annona muricata fruit (i.e. Soursoup or custard apple a tropical plant species known for its edible fruit)has been attributed with numerous medicinal benefits (including antimicrobial, anti-inflammatory, anti-protozoan, antioxidant, anxiolytic, anti-stress, anti-ulcerogenic, wound healing, hepato-protective, anti-icteric, hepatoprotective, anticancer and antihyperglycemic activities) as well as some toxicological effects (neurotoxicity and neurodegeneration). Despite its ancestral use and wide applications in human health, scientific information on its oral safety remains scanty. In this study, the oral safety of 100 mg/kd/day, 200 mg/kg/day and 400 mg/kg/day of the aqueous fruit extract of Annona Muricata (AFAM) was evaluated in young adult, male and female white albino Wistar rats using standard acute and 42-days sub-chronic oral toxicity testing guidelines on anthropometric, biochemical, hematological and histo-pathological endpoints. In addition, preliminary qualitative and quantitative analyses of AFAM were undertaken using standard procedures. Results of the study showed that the estimated LD50 value for the acute oral toxicity study of AFAM calculated to be greater than 5 g/kg body weight/oral route although the testing was associated with transient but reversible behavioral toxicities. For its sub-chronic oral toxicity testing, AFAM treatment resulted in profound %weight gain, decreases in the serum triglycerides and very low density lipoprotein cholesterol and liver enzymes. Similarly, prolonged oral AFAM treatments caused significant decrease and increase in the differential neutrophils and platelet counts, respectively while the hist-opathological features of hepatic steatos is and renal tubule collapse in the AFAM-treated livers and kidneys, respectively suggested possible increased intrahepatic lipids biosynthesis and nephrotoxicity. The preliminary phytochemical analyses of AFAM showed the presence and relative amount of flavonoids, alkaloids, tannin, glycosides, saponin, and reducing sugars while the Gas Chromatography-Mass spectroscopy showed the relative abundance of thirteen compounds. Composite analyses conducted on the extract showed the presence of carbohydrate (64.65%), protein (2.14%), moisture content (8.07%), ash value (6.73%), lipid (14.22%) and fiber (4.19%). Overall, the study suggested that the prolonged AFAM oral treatments could predispose to the development of fatty liver disease from de novo intrahepatic biosynthesis of triglycerides, nephrotoxicity and hematotoxicity. In conclusion, the results of this study showed that prolonged consumption of AFAM should be with a great caution as it could pose serious health concerns.

Endoplasmic reticulum stress PERK-ATF4-CHOP pathway is involved in non-alcoholic fatty liver disease in type 1 diabetic rats: The rescue effect of treatment exercise and insulin-like growth factor I

Endoplasmic Reticulum Stress (ERS) is a key factor in the development of Non-Alcoholic Fatty Liver Disease (NAFLD) in diabetes. The current study aimed to examine the effects of exercise and IGF-I on ERS markers in liver tissue. Rats were divided into five groups (n = 8 per group), including control (CON), diabetes (DIA), diabetes + exercise (DIA + EX), diabetes + IGF-I (DIA + IGF-I), and diabetes + exercise + IGF-I (DIA + EX + IGF-I). Type 1 diabetes was induced by an I.P. injection of streptozotocin (60 mg/kg). After 30 days of treatment with exercise or IGF-I alone or in combination, liver tissue was assessed for caspase 12, 8, and CHOP protein levels, and expression of ERS markers (ATF-6, PERK, IRE-1A) and lipid metabolism-involved genes (FAS, FXR, SREBP-1c) by western immunoblotting. In addition, for the evaluation of histopathological changes in the liver, Hematoxylin - Eosin and Masson's Trichrome staining were done. Compared to the control group, diabetes significantly caused liver fibrosis, induced ERS, increased caspase 12 and 8 levels in the liver, and changed expression levels of genes associated with lipid metabolism, including FAS, FXR, and SREBP-1c. Treatment with either exercise or IGF-I reduced fibrosis levels suppressed ER stress markers and apoptosis, and improved expression of genes associated with lipid metabolism. In addition, simultaneous treatment with exercise and IGF-I showed a synergistic effect compared to DIA + E and DIA + IGF-I. The results suggest that IGF-1 and exercise reduced liver fibrosis possibly by reducing ERS, creating adaptive ER stress status, and improving protein folding.

The association of Neuromedin U levels and non-alcoholic fatty liver disease: A comparative analysis

This comprehensive study delves into the potential link between Neuromedin U (NmU) serum levels and the development of non-alcoholic fatty liver disease (NAFLD), a condition of increasing global prevalence and significant public health concern. The research provides a nuanced understanding of the disease's etiology by examining a cohort of 112 participants, including individuals with and without NAFLD. The study meticulously considers a spectrum of variables such as demographic factors, body composition metrics, and blood parameters. Advanced diagnostic tools like Fibroscan® are employed to ascertain NAFLD presence, ensuring accurate and reliable results.The investigation reveals a noteworthy correlation between NAFLD and several risk factors, notably obesity, increased waist and neck circumferences, hypertriglyceridemia, and insulin resistance. These findings underscore the multifactorial nature of NAFLD and its intricate connection with metabolic syndromes. Intriguingly, the study observes lower NmU levels in individuals diagnosed with NAFLD. However, the role of NmU as an independent risk factor for NAFLD remains inconclusive, warranting further investigation. Although triglyceride level was observed to be an independent risk factor for NAFLD, this relationship was not associated with NmU.This research contributes significantly to the existing knowledge on NAFLD, highlighting the disease's complexity and the interplay of various risk factors. It also opens up new avenues for future research, particularly in exploring the role of NmU within the metabolic pathways associated with NAFLD. The insights gained from this study could guide the development of novel diagnostic and therapeutic strategies for NAFLD, addressing a crucial need in contemporary healthcare.In conclusion, the findings of this study not only enhance the understanding of NAFLD's pathophysiology but also emphasize the importance of comprehensive risk factor analysis in the management and prevention of this growing health concern.

Bacteroides fragilis aggravates high-fat diet-induced non-alcoholic fatty liver disease by regulating lipid metabolism and remodeling gut microbiota.

Gut microbiota dysbiosis is a prominent determinant that significantly contributes to the disruption of lipid metabolism. Consequently, it is essential to the occurrence and development of non-alcoholic fatty liver disease (NAFLD). Nevertheless, the connection between diet and symbiotic gut microbiota in the progression of NAFLD remains uncertain. The purpose of this study was to explore the role of supplementing commensal Bacteroides fragilis (B. fragilis) on lipid metabolism, gut microbiota, and metabolites in high-fat diet (HFD)-fed mice, elucidating the impact of gut microbiota and metabolites on the development of NAFLD. Our study revealed that supplementation with B. fragilis exacerbated both weight gain and obesity in mice. B. fragilis exacerbated blood glucose levels and liver dysfunction in mice. Furthermore, an increase in liver lipid accumulation and the upregulation of genes correlated with lipid metabolism were observed in mice. Under an HFD, supplementation of commensal B. fragilis resulted in alterations in the gut microbiota, notably a significant increase in Desulfovibrionaceae, which led to elevated endotoxin levels and thereby influenced the progression of NAFLD. It was interesting that the simultaneous examination of gut microbiota metabolites revealed a more pronounced impact of diet on short-chain fatty acids. This study represented the pioneering investigation into the impact of B. fragilis on NAFLD. Our findings demonstrated that B. fragilis induced dysregulation in the intestinal microbiota, leading to elevated levels of lipopolysaccharide and dysfunction in glucose and lipid metabolism, thereby exacerbating NAFLD.IMPORTANCESome intestinal symbiotic microbes are involved in the occurrence of the metabolic disorders. Our study investigated the impact of supplementing commensal Bacteroides fragilis on host metabolism in high-fat diet-fed mice. Research results indicated that adding a specific bacterial strain to the complex intestinal microecology can worsen metabolic conditions. This effect mainly affects the structural diversity of intestinal microorganisms, the increase in harmful bacteria in the gut, and the elevation of endotoxin levels, blood glucose, and lipid metabolism, thereby impacting the progression of non-alcoholic fatty liver disease (NAFLD). Understanding the principles that govern the establishment of microbial communities comprising multiple species is crucial for preventing or repairing dysfunctions in these communities, thereby enhancing host health and facilitating disease treatment. This study demonstrated that gut microbiota dysbiosis could contribute to metabolic dysfunction and provides new insights into how to promote gut microbiota in the prevention and therapy of NAFLD.

Diagnostic value of sphingolipid metabolism-related genes CD37 and CXCL9 in nonalcoholic fatty liver disease.

The development of nonalcoholic fatty liver disease (NAFLD) has been reported to be caused by sphingolipid family inducing insulin resistance, mitochondrial dysfunction, and inflammation, which can be regulated by multiple sphingolipid metabolic pathways. This study aimed to explore the molecular mechanism of crucial sphingolipid metabolism related genes (SMRGs) in NAFLD. Firstly, the datasets (GSE48452, GSE126848, and GSE63067) from the Gene Expression Omnibus database and sphingolipid metabolism genes (SMGs) from previous research were collected for this study. The differentially expressed genes (DEGs) between different NAFLD and controls were acquired through "limma," and the SMRGs were authenticated via weighted gene co-expression network analysis (WGCNA). After overlapping the DEGs and SMRGs, the causality between the intersection genes (DE-SMRGs) and NAFLD was explored to sort out the candidate biomarkers by Mendelian randomization (MR) study. The receiver operating characteristic (ROC) curves of candidate biomarkers in GSE48452 and GSE126848 were yielded to determine the biomarkers, followed by the nomogram construction and enrichment analysis. Finally, the immune infiltration analysis, the prediction of transcription factors (TFs) and drugs targeting biomarkers were put into effect. A total of 23 DE-SMRGs were acquired based on the differential analysis and weighted gene co-expression network analysis (WGCNA), of which 3 DE-SMRGs (CD37, CXCL9 and IL7R) were picked out for follow-up analysis through univariate and multivariate MR analysis. The values of area under ROC curve of CD37 and CXCL9 were >0.7 in GSE48452 and GSE126848, thereby being regarded as biomarkers, which were mainly enriched in amino acid metabolism. With respect to the Spearman analysis between immune cells and biomarkers, CD37 and CXCL9 were significantly positively associated with M1 macrophages (P < .001), whose proportion was observably higher in NAFLD patients compared with controls. At last, TFs (ZNF460 and ZNF384) of CD37 and CXCL9 and a total of 79 chemical drugs targeting CD37 and CXCL9 were predicted. This study mined the pivotal SMRGs, CD37 and CXCL9, and systematically explored the mechanism of action of both biomarkers based on the public databases, which could tender a fresh reference for the clinical diagnosis and therapy of NAFLD.

Determinants of non-alcoholic fatty liver disease in young people: Maternal, neonatal, and adolescent factors.

To assess the impact of maternal, neonatal, and adolescent factors on the development of non-alcoholic fatty liver disease (NAFLD) in a cohort of 14- to 19-year-old adolescents. This study is part of the Early Vascular Ageing in the YOUth study, a single-center cross-sectional study conducted in western Austria. Maternal and neonatal factors were extracted from the mother-child booklet, adolescent factors were evaluated by a face-to-face interview, physical examination, and fasting blood analyses. Liver fat content was assessed by controlled attenuation parameter (CAP) using signals acquired by FibroScan® (Echosense, Paris, France). The association of maternal, neonatal, and adolescent factors with CAP values was analyzed using linear regression models. In total, 595 adolescents (27.2% male) aged 17.0 ± 1.3 years were included. 4.9% (n = 29) showed manifest NAFLD with CAP values above the 90th percentile. Male sex (p < 0.001), adolescent triglyceride levels (p = 0.021), Homeostatic Model Assessment for Insulin Resistance index and BMI z-score (p < 0.001, each) showed a significant association with liver fat content in the multivariable analysis. Maternal pre-pregnancy BMI was associated with CAP values after adjustment for sex, age, and birth weight for gestational age (p < 0.001), but this association was predominantly mediated by adolescent BMI (indirect effect b = 1.18, 95% CI [0.69, 1.77]). Components of the metabolic syndrome were the most important predictors of adolescent liver fat content. Therefore, prevention of NAFLD should focus on lifestyle modification in childhood and adolescence.