Vitamin B12 and folate decrease inflammation and fibrosis in NASH by preventing syntaxin 17 homocysteinylation

CCAAT/Enhancer-Binding Protein Beta Nitration Participates in Hyperhomocysteinemia-Induced Cardiomyocyte Autophagic Flux Blockage by Inhibiting Transcription Factor EB Transcription

Aims: Autophagy is a protective mechanism of cardiomyocytes. Hyperhomocysteinemia (HHcy) elevates oxidative and nitrosative stress levels, leading to an abnormal increase in nitration protein, possibly leading to abnormal autophagy regulation in cardiomyocytes. However, the regulatory effect of HHcy on autophagy at the post-translational modification level is still unclear. Here, we aimed to explore the regulatory mechanism of HHcy on transcription factor EB (TFEB) and nitration of CCAAT/enhancer-binding protein beta (C/EBPβ), a transcriptional repressor of Tfeb, on autophagy in cardiomyocytes. Results: In this study, we established the HHcy rat model by feeding a 2.5% (w/w) methionine diet. The nitration level of C/EBPβ was increased in HHcy, which promoted the entry of C/EBPβ into the nucleus, enhanced the transcriptional suppressive effect of C/EBPβ on Tfeb, and induced insufficient autophagy in cardiomyocytes. Furthermore, we confirmed that the Tyr 274 site of C/EBPβ could undergo nitration induced by HHcy. Once C/EBPβ was nitrated on the Tyr 274 site, the nuclear translocation of C/EBPβ and transcription suppressor function of C/EBPβ on Tfeb were enhanced. Innovation and Conclusion: We find that C/EBPβ is a transcriptional repressor of Tfeb, and HHcy induces the nitration at the Tyr 274 site of C/EBPβ, leading to autophagic flux blockage in cardiomyocytes. These data indicated that nitrated C/EBPβ might be a potential therapeutic target against HHcy-induced autophagy insufficiency of cardiomyocytes. Antioxid. Redox Signal. 00, 000-000.

Dietary methionine supplementation promotes mice hematopoiesis after irradiation

BACKGROUND

With the increasing risk of nuclear exposure, more attention has been paid to the prevention and treatment of acute radiation syndrome (ARS). Although amino acids are key nutrients involved in hematopoietic regulation, the impacts of amino acids on bone marrow hematopoiesis following irradiation and the associated mechanisms have not been fully elucidated. Hence, it is of paramount importance to study the changes in amino acid metabolism after irradiation and their effects on hematopoiesis as well as the related mechanisms.

METHODS

The content of serum amino acids was analyzed using metabolomic sequencing. The survival rate and body weight of the irradiated mice were detected after altering the methionine content in the diet. Extracellular matrix (ECM) protein analysis was performed via proteomics analysis. Inflammatory factors were examined by enzyme-linked immunosorbent assay (ELISA). Flow cytometry, Western blotting, and immunofluorescence were employed to determine the mechanism by which S100 calcium-binding protein A4 (S100A4) regulates macrophage polarization.

RESULTS

The survival time of irradiated mice was significantly associated with alterations in multiple amino acids, particularly methionine. A high methionine diet promoted irradiation tolerance, especially in the recovery of bone marrow hematopoiesis, yet with dose limitations. Folate metabolism could partially alleviate the dose bottleneck by reducing the accumulation of homocysteine. Mechanistically, high methionine levels maintained the abundance of ECM components, including collagens and glycoproteins, in the bone marrow post-irradiation, among which the level of S100A4 was significantly changed. S100A4 regulated macrophage polarization via the STAT3 pathway, inhibited bone marrow inflammation and facilitated the proliferation and differentiation of hematopoietic stem/progenitor cells.

CONCLUSIONS

We have demonstrated that an appropriate elevation in dietary methionine enhances irradiation tolerance in mice and explains the mechanism by which methionine regulates bone marrow hematopoiesis after irradiation.

Impact of metabolism-disrupting chemicals and folic acid supplementation on liver injury and steatosis in mother-child pairs

BACKGROUND AND AIMS

Scarce knowledge about the impact of metabolism-disrupting chemicals (MDCs) on steatotic liver disease limits opportunities for intervention. We evaluated pregnancy MDC-mixture associations with liver outcomes, and effect modification by folic acid (FA) supplementation in mother-child pairs.

METHODS

We studied ∼200 mother-child pairs from the Mexican PROGRESS cohort, with measured 43 MDCs during pregnancy (estimated air pollutants, blood/urine metals or metalloids, urine high- and low-molecular-weight phthalate [HMWPs, LMWPs] and organophosphate-pesticide [OP] metabolites), and serum liver enzymes (ALT, AST) at ∼9 years post-parturition. Outcomes included elevated liver enzymes in children and established clinical scores for steatosis and fibrosis in mothers (i.e.

, AST

ALT, FLI, HSI, FIB-4). Bayesian Weighted Quantile Sum regression assessed MDC-mixture associations with liver outcomes. We further examined chemical-chemical interactions and effect modification by self-reported FA supplementation.

RESULTS

In children, many MDC-mixtures were associated with liver injury. Per quartile HMWP-mixture increase, ALT increased by 10.1% (95%CI: 1.67%, 19.4%) and AST by 5.27% (95% CI: 0.80%, 10.1%). LMWP-mixtures and air pollutant-mixtures were associated with higher AST and ALT, respectively. Air pollutant and non-essential metal/element associations with liver enzymes were attenuated by maternal cobalt blood concentrations (p-interactions<0.05). In mothers, only the LMWP-mixture was associated with odds for steatosis [OR=1.53 (95%CI: 1.01, 2.28) for HSI>36, and OR=1.62 (95%CI: 1.05, 2.49) for AST:ALT<1]. In mothers and children, most associations were attenuated (null) at FA supplementation≥600mcg/day (p-interactions<0.05).

CONCLUSIONS

Pregnancy MDC exposures may increase risk for liver injury and steatosis, particularly in children. Adequate FA supplementation and maternal cobalt levels may attenuate these associations.

IMPACT AND IMPLICATIONS

The effects of environmental chemical exposures on steatotic liver diseases are not well understood. In a parallel investigation of mothers and children, we found that pregnancy exposures to metabolism-disrupting chemicals may increase the risk for liver injury and steatosis, especially in the child, and that these associations could be attenuated by higher folic acid and/or cobalt levels. These findings can inform policies to decrease environmental chemical pollution and contribute to the design of clinical interventions addressing the MASLD epidemic.

Associations of serum folate and vitamin B12 levels with all-cause mortality among patients with metabolic dysfunction associated steatotic liver disease: a prospective cohort study

Introduction

Serum folate and vitamin B12 levels correlate with the prevalence of fatty liver disease, but it is not clear how they affect mortality. Therefore, this study aimed to investigate the association of serum folate and vitamin B12 concentrations with all-cause mortality in individuals with metabolic dysfunction-associated steatotic liver disease (MASLD).

Methods

MASLD subjects were from the Third National Health and Nutrition Examination Survey (NHANES III) in the United States, and mortality follow-up data were obtained by linkage to death records from the National Death Index. Multivariable Cox proportional regression models and restricted cubic spline (RCS) models were used to evaluate the association of serum folate/vitamin B12 with all-cause mortality in the MASLD population.

Results

3,636 and 2,125 MASLD individuals were included in the analyses related to serum folate and vitamin B12, respectively. During a follow-up period of more than 20 years, the RCS models demonstrated significant nonlinear associations of both serum folate (P <0.001) and vitamin B12 (P =0.016) with all-cause mortality in MASLD. When their serum concentrations were below the median level, the risk of all-cause mortality decreased with increasing concentration, reaching a lowest risk around the median level, and then leveled off. In the multivariable cox regression model, for vitamin B12, the risk of all-cause mortality was reduced by 42% and 28% in the third and fourth quartile groups, respectively, compared with the lowest quartile group (hazard ratio [HR]=0.58, 95% CI: 0.39-0.86, P =0.008; HR =0.72, 95% CI: 0.54-0.96, P=0.026, respectively). For folate, the risk of all-cause mortality was reduced by 28% in the third quartile compared with the lowest quartile (HR =0.72, 95% CI: 0.57-0.91, P =0.005).

Conclusion

This longitudinal cohort study suggests that low serum folate and vitamin B12 levels in patients with MASLD are significantly associated with an elevated risk of all-cause mortality.

Habitual dietary methyl donor's intake and metabolic profile in obese individuals: a cross-sectional study

Considering the role of dietary methyl donor (DMD) in numerous biochemical processes, we hypothesized that DMD could play an important role in metabolic syndrome such as hyperlipidemia, hypertension, insulin resistance, and appetite in obese individuals. This cross-sectional study was conducted on 335 obese people. We collected dietary data using a valid and reliable 147-question Food Frequency Questionnaire (FFQ). Multivariate multinomial logistic regression was used to estimate the odds ratio (OR) and 95% confidence interval (CI) for the association between dietary methyl intake and cardio-metabolic risk factors. After adjusting for confounding variables, individuals at the fourth and third quartile of DMD, were more likely to have lower low-density lipoprotein cholesterol (LDL-C) (OR = 0.968, CI = 0.943-0.994, P = 0.015 and OR = 0.978, CI = 0.957-0.998, P = 0.03 respectively) versus first quartile. Also, total cholesterol (TC) showed a significant decrease in forth quartile of DMD in model III (OR = 0.974, CI = 0.951-0.997, P = 0.029). Current results suggested that, high DMDs' consumption, significantly associated with decreased risk of cardiometabolic risk factors.

Dietary folate intake and all-cause mortality and cardiovascular mortality in American adults with non-alcoholic fatty liver disease: Data from NHANES 2003 to 2018

BACKGROUND

The relationship between dietary folate intake and prior mortality in adult patients with Non-alcoholic Fatty Liver Disease (NAFLD) has not been clearly studied. We aimed to examine the relationship between dietary folate intake and all-cause and cardiovascular (CVD) mortality in adult NAFLD patients in the US.

METHODS

Using data from National Health and Nutrition Examination Survey (NHANES) 2003-2018 and associated mortality data we conducted a cohort study of US adult NAFLD subjects. Multivariable Cox proportional hazards regression models were used to evaluate the relationship between dietary folate intake and both all-cause mortality and CVD mortality, accounting for potential confounders. The study employed restricted cubic spline analysis to investigate the non-linear association between dietary folate levels and mortality from all causes and cardiovascular disease.

RESULTS

Our final cohort consisted of 3,266 NAFLD patients, with a median follow-up of 10.3 years, 691 deaths were observed, including 221 cardiovascular deaths. Compared to participants with a folate intake in Quartile 1 (≤250 μg/d), those in Quartile 4 (≥467.5 μg/d) had multivariable-adjusted hazard ratios of 0.69 (95% CI, 0.51-0.94) for all-cause mortality (p for trend = 0.028) and 0.55 (95% CI, 0.29-1.04) for CVD mortality (p for trend = 0.107). A non-linear relationship between dietary intake and risk of death was not observed.

CONCLUSION

Greater dietary folate intake is associated with a reduced risk of all-cause in American adults with NAFLD. Higher dietary folate intake not found to be associated with lower CVD mortality. These findings suggest that dietary folate may improve the prognosis of adult NAFLD patients. The measured-response relationship between dietary folate intake and mortality in patients with NAFLD requires further investigation.

Insufficient S-sulfhydration of serum and glucocorticoid-regulated kinase 1 participates in hyperhomocysteinemia-induced liver injury

BACKGROUND & AIMS

Previous studies have established that hyperhomocysteinemia (HHcy) significantly contributes to the development of non-alcoholic steatohepatitis (NASH). Conversely, hydrogen sulfide (H2S) has shown potential in mitigating NASH. Despite these findings, it remains uncertain whether H2S can serve as a therapeutic agent against HHcy-induced liver damage.

METHODS

Mice were fed a high-methionine diet to induce HHcy and HepG2 cells were exposed to homocysteine (Hcy). In both models, we assessed liver injury, H2S concentration, and autophagy levels. For rescue, sodium hydrosulfide (NaHS), an H2S donor, was used to test its potential in reversing hepatic pathological features induced by HHcy.

RESULTS

1) Hcy accumulation led to liver damage and increased autophagy. This was linked to insufficient S-sulfhydration of serum and glucocorticoid-regulated kinase 1 (SGK1) at Cys244 and Cys282, a crucial autophagy regulator. The deficiency in S-sulfhydration was resulted from downregulation of cystathionine-γ-lyase (CSE) and subsequent H2S decrease, leading to SGK1 inactivation. 2) Administration of NaHS reduced the liver damage caused by high Hcy levels and restored H2S levels, promoting the S-sulfhydration and activation of SGK1. 3) Pharmacological inhibition of SGK1 induced autosis, a specific type of cell death caused by overactivation of autophagy. Conversely, a constitutively active mutant of SGK1 (SGK1S422D) significantly decreased autophagy and improved cell viability.

CONCLUSIONS

NaHS supplementation mitigates HHcy-induced liver injury by downregulating hepatic autophagy through the S-sulfhydration and activation of SGK1. This post-translational modification by H2S holds promise as a therapeutic approach for HHcy-induced liver injury.

Effects of hyperhomocysteinemia on follicular development and oocytes quality

In patients with polycystic ovary syndrome (PCOS), the concentration of homocysteine (Hcy) in follicular fluid is inversely correlated with oocyte and embryo quality. Nevertheless, other metabolic abnormalities associated with PCOS may also impact oocyte and early embryo quality. Therefore, it remains uncertain whether reproductive function is affected in patients without PCOS with hyperhomocysteinemia (HHcy). Here, we observed reduced fertility, increased ovarian atretic follicles, and reduced oocyte maturation rates in HHcy mice. Proteomic analyses revealed that HHcy causes mitochondrial dysfunction and reduced expression of zona pellucida proteins (ZP1, ZP2, and ZP3) in oocytes. Transmission electron microscopy confirmed abnormal formation of the zona pellucida and microvilli in oocytes from HHcy mice. Additionally, in vitro fertilization (IVF) demonstrated a reduction in the rate of 2-cell embryo formation in HHcy mice. These findings reveal that HHcy reduces female reproductive longevity by affecting follicular development and oocyte quality.

Vitamin B12 protects necrosis of acinar cells in pancreatic tissues with acute pancreatitis

Pharmacological agents regarding the most optimal treatments of acute pancreatitis remain. One-carbon metabolism nutrients as therapeutic agents in many diseases might be involved in acute pancreatitis. The roles are acquired exploration in acute pancreatitis. We utilized Mendelian randomization to assess the causal impact of folate, homocysteine, and vitamin B12 (VB12) on acute pancreatitis. Wild-type and corresponding genetically modified mouse models were used to verify the genetic correlating findings. A negative association between genetically predicted serum VB12 levels and risks of acute pancreatitis was identified in human population. The transcobalamin receptor (TCblR)/CD320 gene ablation that decreased cellular VB12 uptake and ATP production in pancreatic tissues promoted necrosis, resulting in much severe pathological changes of induced acute pancreatitis in mice. VB12 pretreatment and posttreatment dramatically increased ATP levels in pancreatic tissues and reduced the necrosis, then the elevated levels of amylase in serum, the levels of CK-19, the activity of trypsin, and T lymphocyte infiltration in pancreatic tissues, prevented the pancreatic gross loss and ameliorated histopathological changes of mouse pancreases with induced acute pancreatitis. The results reveal that VB12 is potential as a therapeutic agent to inhibit tissue injuries and adaptive inflammatory responses in the pancreas in patients with acute pancreatitis.

Association of fish intake with all-cause mortality according to CRP levels or inflammation in older adults: a prospective cohort study

BACKGROUND

The relationship between inflammatory response, fish consumption, and mortality risk in older individuals is unclear. We investigated whether C-reactive protein (CRP) levels ≥ 0.1 mg/dL, fish intake, and inflammatory responses are associated with all-cause mortality risk in older adults.

METHODS

This prospective cohort study included older adults aged 85-89 years from the Kawasaki Aging and Wellbeing Project, who did not require daily care. Cohort was recruited from March 2017 to December 2018 (follow-up ended on December 31, 2021). Dietary assessment was conducted using the Brief Self-Administered Diet History Questionnaire. Multivariate Cox proportional hazards regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for all-cause mortality in the CRP ≥ 0.1 mg/dL group; the CRP < 0.1 mg/dL group was used for reference. Within CRP ≥ 0.1 and < 0.1 mg/dL groups, participants were categorized into tertiles of fish intake. HRs and 95% CIs for all-cause mortality in the other groups were estimated using the lower tertile group as a reference.

RESULTS

The study included 996 participants (mean [standard deviation] age, 86.5 [1.37] years; 497 [49.9%] women) with a median CRP level of 0.08 (interquartile range [IQR] = 0.04-0.16). There were 162 deaths during 4,161 person-years of observation; the multivariable-adjusted HR for all-cause mortality in the CRP ≥ 0.1 mg/dL group was 1.86 (95% CI, 1.32-2.62); P < 0.001. In 577 individuals with median (IQR) fish intake of 39.3 g/1000 kcal (23.6-57.6) and CRP level of < 0.1 mg/dL, the multivariable-adjusted HR for all-cause mortality in the higher tertile group of fish intake was 1.15 (0.67-1.97); P = 0.59, non-linear P = 0.84. In 419 individuals with median (IQR) fish intake of 40.7 g/1000 kcal (25.0-60.1) and CRP level of ≥ 0.1 mg/dL, the multivariate-adjusted HR for all-cause mortality in the higher tertile group of fish intake was 0.49 (0.26-0.92); P = 0.026, non-linear P = 0.38, P-value for interaction = 0.040.

CONCLUSIONS

A negative association between fish intake and all-cause mortality was seen in older adults with elevated CRP levels, which is a mortality risk factor. While the results may be limited owing to stringent methods ensuring impartiality, they offer valuable insights for future research.

TRIAL REGISTRATION

UMIN000026053. Registered February 24, 2017.

CHIP ameliorates nonalcoholic fatty liver disease via promoting K63- and K27-linked STX17 ubiquitination to facilitate autophagosome-lysosome fusion

The fusion of autophagosomes and lysosomes is essential for the prevention of nonalcoholic fatty liver disease (NAFLD). Here, we generate a hepatocyte-specific CHIP knockout (H-KO) mouse model that develops NAFLD more rapidly in response to a high-fat diet (HFD) or high-fat, high-fructose diet (HFHFD). The accumulation of P62 and LC3 in the livers of H-KO mice and CHIP-depleted cells indicates the inhibition of autophagosome-lysosome fusion. AAV8-mediated overexpression of CHIP in the murine liver slows the progression of NAFLD induced by HFD or HFHFD feeding. Mechanistically, CHIP induced K63- and K27-linked polyubiquitination at the lysine 198 residue of STX17, resulting in increased STX17-SNAP29-VAMP8 complex formation. The STX17 K198R mutant was not ubiquitinated by CHIP; it interfered with its interaction with VAMP8, rendering STX17 incapable of inhibiting steatosis development in mice. These results indicate that a signaling regulatory mechanism involving CHIP-mediated non-degradative ubiquitination of STX17 is necessary for autophagosome-lysosome fusion.

The Interplay between Liver and Adipose Tissue in the Onset of Liver Diseases: Exploring the Role of Vitamin Deficiency

The deficiency of vitamins, a condition known as "hidden hunger", causes comprehensive pathological states. Research over the years has identified a relationship between liver diseases and hypovitaminosis or defects in vitamin metabolism. The exact mechanisms remain elusive; however, the crucial involvement of specific vitamins in metabolic functions, alongside the reclassification of liver disease as metabolic dysfunction-associated steatotic liver disease (MASLD), has prompted researchers to investigate the potential cause-effect dynamics between vitamin deficiency and liver disease. Moreover, scientists are increasingly investigating how the deficiency of vitamins might disrupt specific organ crosstalk, potentially contributing to liver disease. Although the concept of a dysmetabolic circuit linking adipose tissue and the liver, leading to liver disease, has been discussed, the possible involvement of vitamin deficiency in this axis is a relatively recent area of study, with numerous critical aspects yet to be fully understood. In this review, we examine research from 2019 to July 2024 focusing on the possible link between liver-adipose tissue crosstalk and vitamin deficiency involved in the onset and progression of non-alcoholic fatty liver disease (NAFLD). Studies report that vitamin deficiency can affect the liver-adipose tissue axis, mainly affecting the regulation of systemic energy balance and inflammation.

Esrra regulates Rplp1-mediated translation of lysosome proteins suppressed in metabolic dysfunction-associated steatohepatitis and reversed by alternate day fasting

OBJECTIVE

Currently, little is known about the mechanism(s) regulating global and specific protein translation during metabolic dysfunction-associated steatohepatitis (MASH; previously known as non-alcoholic steatohepatitis, NASH).

METHODS

Unbiased label-free quantitative proteome, puromycin-labelling and polysome profiling were used to understand protein translation activity in vitro and in vivo.

RESULTS

We observed a global decrease in protein translation during lipotoxicity in human primary hepatocytes, mouse hepatic AML12 cells, and livers from a dietary mouse model of MASH. Interestingly, proteomic analysis showed that Rplp1, which regulates ribosome and translation pathways, was one of the most downregulated proteins. Moreover, decreased Esrra expression and binding to the Rplp1 promoter, diminished Rplp1 gene expression during lipotoxicity. This, in turn, reduced global protein translation and Esrra/Rplp1-dependent translation of lysosome (Lamp2, Ctsd) and autophagy (sqstm1, Map1lc3b) proteins. Of note, Esrra did not increase its binding to these gene promoters or their gene transcription, confirming its regulation of their translation during lipotoxicity. Notably, hepatic Esrra-Rplp1-dependent translation of lysosomal and autophagy proteins also was impaired in MASH patients and liver-specific Esrra knockout mice. Remarkably, alternate day fasting induced Esrra-Rplp1-dependent expression of lysosomal proteins, restored autophagy, and reduced lipotoxicity, inflammation, and fibrosis in hepatic cell culture and in vivo models of MASH.

CONCLUSIONS

Esrra regulation of Rplp1-mediated translation of lysosome/autolysosome proteins was downregulated during MASH. Alternate day fasting activated this novel pathway and improved MASH, suggesting that Esrra and Rplp1 may serve as therapeutic targets for MASH. Our findings also provided the first example of a nuclear hormone receptor, Esrra, to not only regulate transcription but also protein translation, via induction of Rplp1.

Autophagy and hepatic lipid metabolism: mechanistic insight and therapeutic potential for MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD) originates from a homeostatic imbalance in hepatic lipid metabolism. Increased fat deposition in the liver of people suffering from MASLD predisposes them to develop further metabolic derangements, including diabetes mellitus, metabolic dysfunction-associated steatohepatitis (MASH), and other end-stage liver diseases. Unfortunately, only limited pharmacological therapies exist for MASLD to date. Autophagy, a cellular catabolic process, has emerged as a primary mechanism of lipid metabolism in mammalian hepatocytes. Furthermore, preclinical studies with autophagy modulators have shown promising results in resolving MASLD and mitigating its progress into deleterious liver pathologies. In this review, we discuss our current understanding of autophagy-mediated hepatic lipid metabolism, its therapeutic modulation for MASLD treatment, and current limitations and scope for clinical translation.

The role and mechanism of SUMO modification in liver disease

Liver disease affects millions of people in the world, and China has the highest prevalence of liver disease in the world. Small ubiquitin-related modifier (SUMO) modification is a highly conserved post-translational modification of proteins. They are widely expressed in a variety of tissues, including the heart, liver, kidney and lung. SUMOylation of protein plays a key role in the occurrence and development of liver disease. Therefore, this study reviewed the effects of SUMO protein on non-alcoholic fatty liver disease (NAFLD), alcoholic liver disease (ALD), viral hepatitis, hepatic fibrosis (HF), hepatocellular carcinoma (HCC), and other liver diseases to provide novel strategies for targeted treatment of liver disease.

Systemic impacts of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) on heart, muscle, and kidney related diseases

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is the most common liver disorder worldwide, with an estimated global prevalence of more than 31%. Metabolic dysfunction-associated steatohepatitis (MASH), formerly known as non-alcoholic steatohepatitis (NASH), is a progressive form of MASLD characterized by hepatic steatosis, inflammation, and fibrosis. This review aims to provide a comprehensive analysis of the extrahepatic manifestations of MASH, focusing on chronic diseases related to the cardiovascular, muscular, and renal systems. A systematic review of published studies and literature was conducted to summarize the findings related to the systemic impacts of MASLD and MASH. The review focused on the association of MASLD and MASH with metabolic comorbidities, cardiovascular mortality, sarcopenia, and chronic kidney disease. Mechanistic insights into the concept of lipotoxic inflammatory "spill over" from the MASH-affected liver were also explored. MASLD and MASH are highly associated (50%-80%) with other metabolic comorbidities such as impaired insulin response, type 2 diabetes, dyslipidemia, hypertriglyceridemia, and hypertension. Furthermore, more than 90% of obese patients with type 2 diabetes have MASH. Data suggest that in middle-aged individuals (especially those aged 45-54), MASLD is an independent risk factor for cardiovascular mortality, sarcopenia, and chronic kidney disease. The concept of lipotoxic inflammatory "spill over" from the MASH-affected liver plays a crucial role in mediating the systemic pathological effects observed. Understanding the multifaceted impact of MASH on the heart, muscle, and kidney is crucial for early detection and risk stratification. This knowledge is also timely for implementing comprehensive disease management strategies addressing multi-organ involvement in MASH pathogenesis.

Identification and Validation of Glycosylation-Related Genes in Obesity and MASH: Insights from Human Liver Samples and a High-Fat Diet Mouse Model

Background

Obesity is reaching epidemic proportions in the developed world. The biosynthesis and degradation of human glycoproteins take place at the highest level in the liver. However, the association between glycosylation and the factors affecting obesity and metabolism-associated steatohepatitis (MASH) is still unclear.

Materials and Methods

Gene expression data of liver samples from obese patients were retrieved from GSE83452 and GSE89632 databases. Difference analysis and machine learning were used to identify hub genes involved in glycosylation and associated with the response of weight loss treatment. A total of 7 glycosylation-related hub genes were identified and then subjected to correlation analysis, immune cells infiltration analysis and ROC (Receiver Operating Characteristic) analysis. We also evaluated the potential function of 7 hub genes in obesity patients. MASH mice were used to validate the glycosylation-related hub genes.

Results

A total of 25 overlapped glycosylation-related genes were identified by DEGs analysis. ACER2, STX17, ARF5, GPC4, ENTPD5, NANP, and DPY19L2 were identified as hub genes. Among these hub genes, ACER2, STX17, ARF5, and ENTPD5 were also differential expressed in MASH patients. ENTPD5 showed increased transcription in obese MASH mice.

Conclusion

The current study identified seven glycosylation-related genes, ACER2, STX17, ARF5, GPC4, ENTPD5, NANP, and DPY19L2, that might play key roles in the development of obesity. ENTPD5 might play a key role in the development of MASH. These findings provide fresh perspectives for expanding the investigation of obesity and MASH.

Role of Folate in Liver Diseases

Folate is a water-soluble B vitamin involved in the synthesis of purines and pyrimidines and is one of the essential vitamins for human growth and reproduction. Folate deficiency due to low dietary intake, poor absorption of folate, and alterations in folate metabolism due to genetic defects or drug interactions significantly increases the risk of diseases such as neural tube defects, cardiovascular disease, cancer, and cognitive dysfunction. Recent studies have shown that folate deficiency can cause hyperhomocysteinemia, which increases the risk of hypertension and cardiovascular disease, and that high homocysteine levels are an independent risk factor for liver fibrosis and cirrhosis. In addition, folate deficiency results in increased secretion of pro-inflammatory factors and impaired lipid metabolism in the liver, leading to lipid accumulation in hepatocytes and fibrosis. There is substantial evidence that folate deficiency contributes to the development and progression of a variety of liver diseases, including non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), alcoholic liver disease (ALD), viral hepatitis, hepatic fibrosis, and liver cancer. Here we review key studies on the role of folate in the pathophysiology of liver diseases, summarize the current status of studies on folate in the treatment of liver diseases, and speculate that folate may be a potential therapeutic target for liver diseases.

Metabolism-Disrupting Chemical Mixtures during Pregnancy, Folic Acid Supplementation, and Liver Injury in Mother-Child Pairs

Background and Aims

Scarce knowledge about the impact of metabolism-disrupting chemicals (MDCs) on liver injury limits opportunities for intervention. We evaluated pregnancy MDC-mixture associations with liver injury and effect modification by folic acid (FA) supplementation in mother-child pairs.

Methods

We studied ∼200 mother-child pairs from the Mexican PROGRESS cohort, with measured 43 MDCs during pregnancy (estimated air pollutants, blood/urine metals or metalloids, urine high- and low-molecular-weight phthalate [HMWPs, LMWPs] and organophosphate-pesticide [OP] metabolites), and serum liver enzymes (ALT, AST) at ∼9 years post-parturition. We defined liver injury as elevated liver enzymes in children, and using established clinical scores for steatosis and fibrosis in mothers (i.e., AST:ALT, FLI, HSI, FIB-4). Bayesian Weighted Quantile Sum regression assessed MDC-mixture associations with liver injury outcomes. We further examined chemical-chemical interactions and effect modification by self-reported FA supplementation.

Results

In children, many MDC-mixtures were associated with liver injury outcomes. Per quartile HMWP-mixture increase, ALT increased by 10.1% (95%CI: 1.67%, 19.4%) and AST by 5.27% (95% CI: 0.80%, 10.1%). LMWP-mixtures and air pollutant-mixtures were associated with higher AST and ALT, respectively. Air pollutant and non-essential metal/element associations with liver enzymes were attenuated by maternal cobalt blood concentrations ( p -interactions<0.05). In mothers, only the LMWP-mixture was associated with liver injury [OR=1.53 (95%CI: 1.01, 2.28) for HSI>36, and OR=1.62 (95%CI: 1.05, 2.49) for AST:ALT<1]. In mothers and children, most associations were attenuated (null) at FA supplementation≥600mcg/day ( p -interactions<0.05).

Conclusions

Pregnancy MDC exposures may increase liver injury risk, particularly in children. These associations may be attenuated by higher FA supplementation and maternal cobalt levels.

Effect of supplementing lysins and methionine to low-protein diets on growth performance, hepatic antioxidant capacity, immune status, and glycolytic activity of tibetan sheep

Reducing the levels of dietary protein is an effective nutritional approach in lowering feed cost and nitrogen emissions in ruminants. The purpose of this study was to evaluate the effects of dietary Lys/Met ratio in a low protein diet (10%, dry matter basis) on the growth performance and hepatic function (antioxidant capacity, immune status, and glycolytic activity) in Tibetan lambs. Ninety two-month-old rams with an average weight of 15.37 ± 0.92 kg were randomly assigned to LP-L (dietary Lys/Met = 1:1), LP-M (dietary Lys/Met = 2:1) and LP-H (dietary Lys/Met = 3:1) treatments. The trial was conducted over 100 d, including 10 d of adaption to the diets. Hepatic phenotypes, antioxidant capacity, immune status, glycolytic activity and gene expression profiling was detected after the conclusion of the feeding trials. The results showed that the body weight was higher in the LP-L group when compared to those on the LP-M group (P < 0.05). In addition, the activities of the catalase (CAT) and glutathione peroxidase (GSH-Px) in the LP-L group were significantly increased compared with the LP-M group (P < 0.05), while the malondialdehyde (MDA) levels in LP-H group were significantly decreased (P < 0.05). Compared with LP-H group, both hepatic glycogen (P < 0.01) and lactate dehydrogenase (LDH) (P < 0.05) were significantly elevated in LP-L group. For the LP-L group, the hepatocytes were arranged radially with the central vein in the center, and hepatic plates exhibited tight arrangement. Transcriptome analysis identified 29, 179, and 129 differentially expressed genes (DEGs) between the LP-M vs. LP-L, LP-H vs. LP-M, and LP-H vs. LP-L groups, respectively (Q-values < 0.05 and |log2Fold Change| > 1). Gene Ontology (GO) and correlation analyses showed that in the LP-L group, core genes (C1QA and JUNB) enriched in oxidoreductase activity were positively correlated with antioxidant indicators, while the MYO9A core gene enriched in the immune response was positively associated with immune indicators, and core genes enriched in molecular function (PDK3 and PDP2) were positively correlated with glycolysis indicators. In summary, low-protein diet with a low Lys/Met ratio (1:1) could reduce the hepatic oxidative stress and improve the glycolytic activity by regulating the expression of related genes of Tibetan sheep.

Lower hepatic CBS and PEMT expression in advanced NAFLD: inferencing strategies to lower homocysteine with a mathematical model

Aim: Hepatic homocysteine (Hcy) accumulation promotes inflammation and fibrosis in experimental nonalcoholic fatty liver disease (NAFLD), while vitamin B12 and folate reduce hepatic Hcy and protect animals from nonalcoholic steatohepatitis. This suggests clinical implications for preventing/treating patients with NAFLD. Given the known sex-specific regulation of one-carbon metabolism (OCM), the response to various OCM cofactors may vary by sex and reproductive status. We aimed to strategize an effective Hcy-lowering treatment in broader NAFLD patients while discerning disparities in treatment responses.

Methods: We analyzed existing hepatic microarray data relevant to Hcy metabolism with clinical and histologic data from patients with NAFLD (N = 82), while considering potential age/sex disparities. Additionally, we performed computer simulation analyses using a mathematical model of OCM to predict hepatic Hcy-lowering effects of OCM cofactors by sex.

Results: Of 82 patients with NAFLD, 98% had at least one metabolic feature [i.e., metabolic dysfunction-associated steatotic liver disease (MASLD)]. Lower hepatic gene expressions of cystathionine-beta synthase (CBS ) and phosphatidyl- ethanolamine N-methyltransferase (PEMT ) were associated with more severe fibrosis in NAFLD, while sub-analysis suggested possible variations by age and sex. The simulation analysis demonstrated sex differences in the Hcy-lowering effects of the OCM cofactors (vitamins B6 and B12, folate, and betaine), with the combination of these cofactors consistently showing the maximum Hcy-lowering effect in both sexes.

Conclusion: We theorize that the combination of OCM cofactors would maximize Hcy-lowering effects in the broader MASLD population. Our findings also underscore the importance of considering sex and age in designing future studies on homocysteine metabolism.

N-homocysteinylation of DJ-1 promotes neurodegeneration in Parkinson's disease

DJ-1, also known as Parkinson's disease protein 7 (Park7), is a multifunctional protein that regulates oxidative stress and mitochondrial function. Dysfunction of DJ-1 is implicated in the pathogenesis of Parkinson's disease (PD). Hyperhomocysteinemia is associated with an increased risk of PD. Here we show that homocysteine thiolactone (HTL), a reactive thioester of homocysteine (Hcy), covalently modifies DJ-1 on the lysine 182 (K182) residue in an age-dependent manner. The N-homocysteinylation (N-hcy) of DJ-1 abolishes its neuroprotective effect against oxidative stress and mitochondrial dysfunction, exacerbating cell toxicity. Blocking the N-hcy of DJ-1 restores its protective effect. These results indicate that the N-hcy of DJ-1 abolishes its neuroprotective effect and promotes the progression of PD. Inhibiting the N-hcy of DJ-1 may exert neuroprotective effect against PD.

Examining the Pathogenesis of MAFLD and the Medicinal Properties of Natural Products from a Metabolic Perspective

Metabolic-associated fatty liver disease (MAFLD), characterized primarily by hepatic steatosis, has become the most prevalent liver disease worldwide, affecting approximately two-fifths of the global population. The pathogenesis of MAFLD is extremely complex, and to date, there are no approved therapeutic drugs for clinical use. Considerable evidence indicates that various metabolic disorders play a pivotal role in the progression of MAFLD, including lipids, carbohydrates, amino acids, and micronutrients. In recent years, the medicinal properties of natural products have attracted widespread attention, and numerous studies have reported their efficacy in ameliorating metabolic disorders and subsequently alleviating MAFLD. This review aims to summarize the metabolic-associated pathological mechanisms of MAFLD, as well as the natural products that regulate metabolic pathways to alleviate MAFLD.

The lack of PPARα exacerbated the progression of non-alcoholic steatohepatitis in mice with spleen deficiency syndrome by triggering an inflammatory response

Background

In addition to abnormal liver inflammation, the main symptoms of non-alcoholic steatohepatitis (NASH) are often accompanied by gastrointestinal digestive dysfunction, consistent with the concept of spleen deficiency (SD) in traditional Chinese medicine. As an important metabolic sensor, whether peroxisome proliferator-activated receptor alpha (PPARα) participates in regulating the occurrence and development of NASH with SD (NASH-SD) remains to be explored.

Methods

Clinical liver samples were collected for RNA-seq analysis. C57BL/6J mice induced by folium sennae (SE) were used as an SD model. qPCR analysis was conducted to evaluate the inflammation and metabolic levels of mice. PPARα knockout mice (PPARαko) were subjected to SE and methionine-choline-deficient (MCD) diet to establish the NASH-SD model. The phenotype of NASH and the inflammatory indicators were measured using histopathologic analysis and qPCR as well.

Results

The abnormal expression of PPARα signaling, coupled with metabolism and inflammation, was found in the results of RNA-seq analysis from clinical samples. SD mice showed a more severe inflammatory response in the liver evidenced by the increases in macrophage biomarkers, inflammatory factors, and fibrotic indicators in the liver. qPCR results also showed differences in PPARα between SD mice and control mice. In PPARαko mice, further evidence was found that the lack of PPARα exacerbated the inflammatory response phenotype as well as the lipid metabolism disorder in NASH-SD mice.

Conclusion

The abnormal NR signaling accelerated the vicious cycle between lipotoxicity and inflammatory response in NAFLD with SD. Our results provide new evidence for nuclear receptors as potential therapeutic targets for NAFLD with spleen deficiency.

Progress and hotspot of diet or exercise therapy in the treatment of non-alcoholic fatty liver disease

Introduction

The primary treatment for non-alcoholic fatty liver disease (NAFLD) is modifying lifestyle through dietary or exercise interventions. In recent decades, it has received increasing attention. However, the lack of bibliometric analysis has posed a challenge for researchers seeking to understand the overall trends in this field.

Methods

As of February 3rd, 2024, 876 articles on treating NAFLD through diet or exercise therapy from 2013 to 2023 had been retrieved. Two software tools, VOSviewer and CiteSpace, were utilized to analyze the growth of publications, countries, institutions, authors, journals, citations, and keywords. Additionally, the keywords with strong citation burstiness were identified to determine the changes and future trends of research hotspots in this field.

Results

China had the highest number of articles, followed by the United States and South Korea. Yonsei University and Nutrients were the institutions and journals with the most significant contributions. Professor Younossi Zobair M, from the United States, is the most prolific author in this field. Through analyzing the keywords, three research hotspots were identified: research on the pathogenesis of NAFLD, research on the treatment modalities of NAFLD, and research on the risk factors and diagnosis methods of NAFLD. In recent years, the research emphasis in this field has changed, suggesting that future research will focus on two frontier keywords: "oxidative stress" and "aerobic capacity."

Conclusion

In the past eleven years, the attention in this field was still rising, and the authors, journals, countries and so on had formed a considerable cooperative relationship. There were also many highly influential and productive researchers in this field. It is speculated that new research will continue around "aerobic exercise" and "oxidative stress" in the future.

Serum vitamins and homocysteine levels in autoimmune liver disease: A systematic review and meta-analysis

OBJECTIVE

Vitamins and homocysteine (Hcy) are involved in liver metabolism and related to the pathogenesis of autoimmune liver disease (AILD), but consensus is lacking. This study aims to systematically summarize relevant evidence to clarify the association of serum vitamins and Hcy levels with AILD.

METHODS

The English and Chinese literature was searched until August 29, 2023. Studies were included if they were observational studies of investigating serum vitamins and Hcy levels in patients with AILD and their healthy comparisons. Quality assessment was performed by using the Newcastle-Ottawa Scale, and a meta-analysis was conducted using ReviewManager 5.3. The protocol was registered in the international prospective register of systematic reviews (PROSPERO), with registration number CRD42023455367.

RESULTS

A total of 25 case-control studies comprising 3487 patients (1673 patients and 1814 healthy controls) were included for analysis. There were 548 autoimmune hepatitis (AIH) cases, 1106 primary biliary cholangitis (PBC) cases, and 19 primary sclerosing cholangitis (PSC) cases. We found that serum A and E were decreased in both AIH and PBC/PSC; but vitamin C was reduced only in patients with PBC, not AIH. In addition, decreased content of 25(OH)D3 was found in both AIH and PBC. However, levels of 25(OH)D did not differ between the patients and controls, and were independent of disease types and the country. Only one study that met the inclusion criteria reported vitamin B6, B9, B12, and Hcy changes, and found that vitamin B6 and B9 were significantly decreased in patients with PBC, while serum vitamin B12 and Hcy levels were significantly elevated in them. One eligible study each confirmed a reduction in plasma vitamin K1 and 1,25(OH)2D3 in patients with PBC.

CONCLUSION

Most vitamins are deficient in AILD, so appropriate vitamin supplementation should be necessary. Further studies with larger sample sizes are needed to validate these findings.

Exploring the causal associations of micronutrients on urate levels and the risk of gout: A Mendelian randomization study

BACKGROUND & AIMS

Growing evidence has indicated a potential association between micronutrient levels, urate levels, and the risk of gout. However, the causal association underlying these associations still remains uncertain. Previous observational studies and randomized controlled trials investigating the association between micronutrients, urate levels, and the risk of gout have been limited in their scope and depth. The aim of this study was to utilize Mendelian randomization (MR) to investigate the causal associations between genetically predicted micronutrient levels, urate levels, and the risk of gout.

METHODS

In this study, we conducted a comprehensive examination of 10 specific micronutrients (vitamin B6, vitamin B12, vitamin C, vitamin D, folate, calcium, iron, copper, zinc, and selenium) as potential exposures. Two-sample MR analyses were performed to explore their causal associations with urate levels and the risk of gout. In these analyses, gout data were collected from the Global Biobank Meta-Analysis Initiative (N = 1,069,839, N cases = 30,549) and urate levels data from CKDGen Consortium (N = 288,649) by utilizing publicly available summary statistics from independent cohorts of European ancestry. We performed inverse-variance weighted MR analyses as main analyses, along with a range of sensitivity analyses, such as MR-Egger, weighted median, simple mode, weighted mode, Steiger filtering, MR-PRESSO, and Radial MR analysis, to ensure the robustness of our findings.

RESULTS

The results of our study indicate that there were negative associations between serum vitamin B12 and urate levels, as well as serum folate and the risk of gout. Specifically, we found a negative association between vitamin B12 levels and urate levels, with a β coefficient of -0.324 (95% CI -0.0581 to -0.0066, P = 0.0137) per one standard deviation (SD) increase. Similarly, a negative association was observed between folate levels and gout risk, with an odds ratio of 0.8044 (95% CI 0.6637 to 0.9750, P = 0.0265) per one SD increase. On the other hand, we identified positive associations between serum calcium levels and both urate levels and the risk of gout. Specifically, there was a positive association between serum calcium levels and urate levels (β coefficient: 0.0994, 95% CI 0.0519 to 0.1468, P = 4.11E-05) per one SD increase. Furthermore, a positive association was found between serum calcium levels and the risk of gout, with an odds ratio of 1.1479 (95% CI 1.0460 to 1.2598, P = 0.0036) per one SD increase. These findings were robust in extensive sensitivity analyses. By employing MR-PRESSO and Radial MR to eliminate outliers, the observed associations have been reinforced. No clear associations were found between the other micronutrients and the urate levels, as well as the risk of gout.

CONCLUSION

Our findings provided evidence that there were negative associations between serum vitamin B12 and urate levels, as well as serum folate and the risk of gout, while positive associations existed between the serum calcium levels and urate levels, as well as the risk of gout.

Molecular mechanism and therapeutic significance of essential amino acids in metabolically associated fatty liver disease

Non-alcoholic fatty liver disease (NAFLD), also known as metabolically associated fatty liver disease (MAFLD), is a systemic metabolic disease characterized by lipid accumulation in the liver, lipid toxicity, insulin resistance, intestinal dysbiosis, and inflammation that can progress from simple steatosis to nonalcoholic steatohepatitis (NASH) and even cirrhosis or cancer. It is the most prevalent illness threatening world health. Currently, there are almost no approved drug interventions for MAFLD, mainly dietary changes and exercise to control weight and regulate metabolic disorders. Meanwhile, the metabolic pathway involved in amino acid metabolism also influences the onset and development of MAFLD in the body, and most amino acid metabolism takes place in the liver. Essential amino acids are those amino acids that must be supplemented from outside the diet and that cannot be synthesized in the body or cannot be synthesized at a rate sufficient to meet the body's needs, including leucine, isoleucine, valine (collectively known as branched-chain amino acids), tryptophan, phenylalanine (which are aromatic amino acids), histidine, methionine, threonine and lysine. The metabolic balance of the body is closely linked to these essential amino acids, and essential amino acids are closely linked to the pathophysiological process of MAFLD. In this paper, we will focus on the metabolism of essential amino acids in the body and further explore the therapeutic strategies for MAFLD based on the studies conducted in recent years.

Folic Acid Rescues Dopaminergic Neurons in MPTP-Induced Mice by Inhibiting the NLRP3 Inflammasome and Ameliorating Mitochondrial Impairment

Parkinson's disease (PD) is marked by the degeneration of dopaminergic neurons of the substantia nigra (SN), with neuroinflammation and mitochondrial dysfunction being key contributors. The neuroprotective potential of folic acid (FA) in the dopaminergic system of PD was assessed in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model. MPTP (20 mg/kg of body weight) was administered to C57BL/6J mice to simulate PD symptoms followed by FA treatment (5 mg/kg of body weight). Behavioral tests, pole, rotarod, and open-field tests, evaluated motor function, while immunohistochemistry, ELISA, RT-qPCR, and Western blotting quantified neuroinflammation, oxidative stress markers, and mitochondrial function. FA supplementation considerably improved motor performance, reduced homocysteine levels and mitigated oxidative damage in the SN. The FA-attenuated activation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome lessened glial cell activity and reduced neuroinflammation. At the molecular level, FA reduced DNA damage, downregulated phosphorylated p53, and induced the expression of peroxisome proliferator-activated receptor α coactivator 1α (PGC-1α), enhancing mitochondrial function. Therefore, FA exerts neuroprotection in MPTP-induced PD by inhibiting neuroinflammation via NLRP3 inflammasome suppression and promoting mitochondrial integrity through the p53-PGC-1α pathway. Notable limitations of our study include its reliance on a single animal model and the incompletely elucidated mechanisms underlying the impact of FA on mitochondrial dynamics. Future investigations will explore the clinical utility of FA and its molecular mechanisms, further advancing it as a potential therapeutic for managing and delaying the progression of PD.

The association between diverse serum folate with MAFLD and liver fibrosis based on NHANES 2017-2020

Background

Metabolically Associated Fatty Liver Disease (MAFLD) marks a progression from the previous paradigm of Non-Alcoholic Fatty Liver Disease (NAFLD), presenting a redefined diagnostic framework that accentuates metabolic factors while recognizing non-alcoholic contributors. In our investigation, our principal aim was to scrutinize the conceivable correlation between diverse serum folate levels and the prevalence of MAFLD and liver fibrosis.

Methods

In our investigation, we conducted an extensive analysis utilizing data derived from the National Health and Nutrition Examination Survey (NHANES) across the years 2017-2020. We aimed to investigate the association between different serum folate concentrations and the prevalence of MAFLD and liver fibrosis by comprehensive multivariate analysis. This analytical approach considered various variables, encompassing sociodemographic characteristics, lifestyle factors, hypertension, and diabetes. By including these potential confounders in our analysis, we aimed to ensure the stability of the findings regarding the association between different serum folate concentrations and the development of MAFLD and liver fibrosis.

Results

In our investigation, we utilized multiple linear regression models to thoroughly analyze the data, revealing noteworthy insights. Evidently, elevated levels of both total folate and 5-MTHF exhibited a distinct negative correlation with CAP, while 5-MTHF demonstrated a notable negative correlation with LSM. Furthermore, multiple logistic regression models were employed for an in-depth examination of the data. As the concentrations of total folate and 5-MTHF in the serum increased, a substantial decrease in the likelihood of MAFLD and liver fibrosis occurrence was observed.

Conclusion

The findings of this investigation robustly suggest the prevalence of MAFLD and liver fibrosis decreased significantly with the increase of serum concentrations of total folate and 5-MTHF.

Association of multiple serum minerals and vitamins with metabolic dysfunction-associated fatty liver disease in US adults: National Health and Nutrition Examination Survey 2017-2018

Background

Despite the rapid increase in the global prevalence of Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD), there are no approved therapeutic drugs for MAFLD yet. Nutrient supplementation might mitigate the risk of MAFLD. It is more typical for individuals to consume multiple nutrients simultaneously. However, the studies exploring the combined effects of multiple nutrients on MAFLD are limited. This study aimed to investigate the relationship between both individual nutrients and their combined influence on the risk of MAFLD.

Methods

Data were obtained from National Health and Nutrition Examination Survey (NHANES), and 18 types of nutrients were considered in this study. Logistic regression analysis was performed to evaluate the correlation between single nutrients and the risk of MAFLD. The Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis was performed to pinpoint the most relevant nutrient associated with the risk of MAFLD. Subsequently, both Weighted Quantile Sum (WQS) regression and Quantile g-computation (Qgcomp) were used to assess the combined effects of multiple nutrients on the risk of MAFLD.

Results

A total of 3,069 participants were included in this study. LASSO regression analysis showed that Se, α-tocopherol, and γ-tocopherol exhibited a positive association with the risk of MAFLD. In contrast, the serum levels of Co, P, α-cryptoxanthin, LZ, and trans-β-carotene were inversely associated with the prevalence of MAFLD. When Se and two types of vitamin E were excluded, the WQS index showed a significant inverse relationship between the remaining 15 nutrients and the risk of MAFLD; α-cryptoxanthin showed the most substantial contribution. Similarly, Qgcomp suggested that the combined effects of these 15 nutrients were associated with a lower risk of MAFLD, with α-cryptoxanthin possessing the most significant negative weights.

Conclusion

This study suggested that the complex nutrients with either a low proportion of Se, α-tocopherol, and γ-tocopherol or without them should be recommended for patients with MAFLD to reduce its risk.

Folate Deficiency and/or the Genetic Variant Mthfr677C >T Can Drive Hepatic Fibrosis or Steatosis in Mice, in a Sex-Specific Manner

SCOPE

Disturbances in one-carbon metabolism contribute to nonalcoholic fatty liver disease (NAFLD) which encompasses steatosis, steatohepatitis, fibrosis, and cirrhosis. The goal is to examine impact of folate deficiency and the Mthfr677C >T variant on NAFLD.

METHODS AND RESULTS

This study uses the new Mthfr677C >T mouse model for the human MTHFR677C >T variant. Mthfr677CC and Mthfr677TT mice were fed control diet (CD) or folate-deficient (FD) diets for 4 months. FD and Mthfr677TT alter choline/methyl metabolites in liver and/or plasma (decreased S-adenosylmethionine (SAM):S-adenosylhomocysteine (SAH) ratio, methyltetrahydrofolate, and betaine; increased homocysteine [Hcy]). FD, with contribution from Mthfr677TT, provokes fibrosis in males. Studies of normal livers reveal alterations in plasma markers and gene expression that suggest an underlying predisposition to fibrosis induced by FD and/or Mthfr677TT in males. These changes are absent or reverse in females, consistent with the sex disparity of fibrosis. Sex-based differences in methylation potential, betaine, sphingomyelin, and trimethylamine-N-oxide (TMAO) levels may prevent fibrogenesis in females. In contrast, Mthfr677TT alters choline metabolism, dysregulates expression of lipid metabolism genes, and promotes steatosis in females.

CONCLUSION

This study suggests that folate deficiency predisposes males to fibrosis, which is exacerbated by Mthfr677TT, whereas Mthfr677TT predisposes females to steatosis, and reveal novel contributory mechanisms for these NAFLD-related disorders.

Higher circulating vitamin B12 is associated with lower levels of inflammatory markers in individuals at high cardiovascular risk and in naturally aged mice

BACKGROUND

Vitamin B12 is an essential nutrient that is involved in numerous physiological processes, and its deficiency can lead to various complications, including neurological and haematological disorders. Some studies have suggested that vitamin B12 may have anti-inflammatory effects, but the mechanisms underlying this relationship are not yet fully understood. We investigated the relationship between circulating vitamin B12 and inflammatory markers interleukin (IL)-6 and C-reactive protein (CRP). The association of peripheral levels of vitamin B12 with IL-6 and CRP was assessed in 136 human samples from a high cardiovascular risk population. To corroborate the results from the human trial, the analysis was replicated in naturally aged mice.

RESULTS

Individuals with higher serum levels of vitamin B12 showed lower concentrations of IL-6 and CRP after adjustment for potential confounders, and an inverse association was also found between serum IL-6 and vitamin B12 levels in naturally aged mice.

CONCLUSION

Circulating vitamin B12 was inversely associated with IL-6 and CRP in humans and with IL-6 in mice, suggesting that it may exert an anti-inflammatory effect through modulation of these pro-inflammatory molecules. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Genetically determined circulating micronutrients and the risk of nonalcoholic fatty liver disease

Evidence from epidemiological literature on the association of circulating micronutrients with risk of nonalcoholic fatty liver disease (NAFLD) is inconsistent. We aimed to elucidate the causal relationships using Mendelian randomization (MR). Single-nucleotide polymorphisms associated with 14 circulating micronutrients (β-carotene, calcium, copper, folate, iron, magnesium, phosphorus, selenium, vitamin B6, B12, C, D, K1 and zinc) were employed as instrumental variables. Summary level data for NAFLD were obtained from a genome-wide association study (GWAS) meta-analysis of 8434 cases and 770,180 controls (discovery stage) and another two datasets including 1483 NAFLD cases and 17,781 controls (replication stage 1) and 2134 NAFLD cases and 33,433 controls (replication stage 2). Inverse variance-weighted method (IVW) was used as primary analysis, supplemented with a series of sensitivity analysis. Genetically predicted higher β‑carotene levels were suggestively associated with reduced NAFLD risk [odds ratio (OR) 0.81, 95% confidence interval (CI) 0.66-0.99; P = 0.047], whereas the association did not survive the false discovery rates (FDR) correction (PFDR = 0.164). Genetically predicted circulating iron (OR 1.16, 95% CI 1.05-1.29; P = 0.006, PFDR = 0.028), selenium (OR 1.11, 95% CI 1.03-1.20; P = 0.005, PFDR = 0.028) and vitamin B12 (OR 1.08, 95% CI 1.03-1.13; P = 0.002, PFDR = 0.028) were significantly associated with increased risk of NAFLD. Moreover, the findings were consistent in individual datasets (Pheterogeneity > 0.05) and confirmed in sensitivity analysis. Our study provided evidence that circulating iron, selenium and vitamin B12 might be causally linked to the risk of NAFLD, which deserves further exploration of the potential biological mechanism.

Navigating the B vitamins: Dietary diversity, microbial synthesis, and human health

B vitamins are intricately involved in various physiological processes vital for health. Their significance is complicated by the heterogeneous landscape of B vitamin distribution in diets and the contributions of the gut microbiota. Here, we delve into the impact of these factors on B vitamins and introduce strategies, with a focus on microbiota-based therapeutic options, to enhance their availability for improved well-being. Additionally, we provide an ecological and evolutionary perspective on the importance of B vitamins to human-microbiota interactions. In the dynamic realms of nutrition and microbiome science, these essential micronutrients continue to play a fundamental role in our understanding of disease development.

Estrogen receptor-related receptor (Esrra) induces ribosomal protein Rplp1-mediated adaptive hepatic translation during prolonged starvation

Protein translation is an energy-intensive ribosome-driven process that is reduced during nutrient scarcity to conserve cellular resources. During prolonged starvation, cells selectively translate specific proteins to enhance their survival (adaptive translation); however, this process is poorly understood. Accordingly, we analyzed protein translation and mRNA transcription by multiple methods in vitro and in vivo to investigate adaptive hepatic translation during starvation. While acute starvation suppressed protein translation in general, proteomic analysis showed that prolonged starvation selectively induced translation of lysosome and autolysosome proteins. Significantly, the expression of the orphan nuclear receptor, estrogen-related receptor alpha (Esrra) increased during prolonged starvation and served as a master regulator of this adaptive translation by transcriptionally stimulating 60S acidic ribosomal protein P1 (Rplp1) gene expression. Overexpression or siRNA knockdown of Esrra expression in vitro or in vivo led to parallel changes in Rplp1 gene expression, lysosome/autophagy protein translation, and autophagy. Remarkably, we have found that Esrra had dual functions by not only regulating transcription but also controling adaptive translation via the Esrra/Rplp1/lysosome/autophagy pathway during prolonged starvation.

Cell-type specific role of autophagy in the liver and its implications in non-alcoholic fatty liver disease

Autophagy, a cellular degradative process, has emerged as a key regulator of cellular energy production and stress mitigation. Dysregulated autophagy is a common phenomenon observed in several human diseases, and its restoration offers curative advantage. Non-alcoholic fatty liver disease (NAFLD), more recently renamed metabolic dysfunction-associated steatotic liver disease, is a major metabolic liver disease affecting almost 30% of the world population. Unfortunately, NAFLD has no pharmacological therapies available to date. Autophagy regulates several hepatic processes including lipid metabolism, inflammation, cellular integrity and cellular plasticity in both parenchymal (hepatocytes) and non-parenchymal cells (Kupffer cells, hepatic stellate cells and sinusoidal endothelial cells) with a profound impact on NAFLD progression. Understanding cell type-specific autophagy in the liver is essential in order to develop targeted treatments for liver diseases such as NAFLD. Modulating autophagy in specific cell types can have varying effects on liver function and pathology, making it a promising area of research for liver-related disorders. This review aims to summarize our present understanding of cell-type specific effects of autophagy and their implications in developing autophagy centric therapies for NAFLD.

Nutritional deficiency anemia and post-acute sequelae in patients with severe acute respiratory syndrome coronavirus 2 infection: A six-month retrospective cohort analysis of 30 892 patients

The effect of anemia on the post-acute outcome of patients with severe acute respiratory syndrome coronavirus 2 infection was unclear. This study aimed to investigate the potential association between nutritional deficiency anemia (NDA) status and post-acute sequelae of patients with SARS-CoV-2 infection. This retrospective cohort study included patients with coronavirus disease (COVID-19) from January 1, 2022 to November 30, 2022 using the TriNetX research network. The patients were grouped into the NDA group comprising patients diagnosed with NDA and the control group comprising patients without NDA, and propensity score matching (PSM) was performed to balance the two groups. The primary outcome was a composite of post-COVID-19 condition, all-cause hospitalization, and all-cause death. The secondary outcomes were any individual outcomes of the primary composite. The follow-up period was set at 90-180 days after COVID-19 diagnosis. Two cohorts comprising 15 446 nonhospitalized patients with COVID-19 in each group with balanced baseline characteristics were created using PSM. During the follow-up period, the NDA group demonstrated a higher risk of the composite primary outcome, including post-COVID-19 condition, all-cause hospitalization, or all-cause death (hazard ratio [HR], 1.896; 95% confidence interval [CI] =  1.757-2.045). Regarding secondary outcomes, the NDA group was associated with worse outcomes, including post-COVID-19 condition (HR, 1.992; 95% CI = 1.403-2.828), all-cause hospitalization (HR, 1.856; 95% CI = 1.714-2.009), and all-cause death (HR, 3.922; 95% CI = 2.910-5.285) compared to the control group. Among nonhospitalized patients with COVID-19, NDA was associated with a higher risk of post-COVID-19 condition, all-cause hospitalization, and all-cause death during the 90-180-day follow-up period.

Microbial modifications with Lycium barbarum L. oligosaccharides decrease hepatic fibrosis and mitochondrial abnormalities in mice

BACKGROUND

Lycium barbarum L. is a typical Chinese herbal and edible plant and are now consumed globally. Low molecular weight L. barbarum L. oligosaccharides (LBO) exhibit better antioxidant activity and gastrointestinal digestibility in vitro than high molecular weight polysaccharides. However, the LBO on the treatment of liver disease is not studied.

PURPOSE

Modification of the gut microbial ecosystem by LBO is a promising treatment for liver fibrosis.

STUDY DESIGN AND METHODS

Herein, LBO were prepared and characterized. CCl4-treated mice were orally gavaged with LBO and the effects on hepatic fibrosis and mitochondrial abnormalities were evaluated according to relevant indicators (gut microbiota, faecal metabolites, and physiological and biochemical indices).

RESULTS

The results revealed that LBO, a potential prebiotic source, is a pyranose cyclic oligosaccharide possessing α-glycosidic and β-glycosidic bonds. Moreover, LBO supplementation restored the configuration of the bacterial community, enhanced the proliferation of beneficial species in the gastrointestinal tract (e.g., Bacillus, Tyzzerella, Fournierella and Coriobacteriaceae UCG-002), improved microbial metabolic alterations (i.e., carbohydrate metabolism, vitamin metabolism and entero-hepatic circulation), and increased antioxidants, including doxepin, in mice. Finally, LBO administration reduced serum inflammatory cytokine and hepatic hydroxyproline levels, improved intestinal and hepatic mitochondrial functions, and ameliorated mouse liver fibrosis.

CONCLUSION

These findings indicate that LBO can be utilized as a prebiotic and has a remarkable ability to mitigate liver fibrosis.

Association between dietary intakes of B vitamins and nonalcoholic fatty liver disease in postmenopausal women: a cross-sectional study

Background

Non-alcoholic fatty liver disease (NAFLD) is increasingly common globally, particularly among postmenopausal women. Diet plays a fundamental role in the treatment of NAFLD. However, clinical research on the dietary intakes of B vitamins, specifically in postmenopausal women, is scant. Hence, it is imperative to study the impact of B vitamin dietary intake in postmenopausal women.

Methods

This study utilized National Health and Nutrition Examination Survey (NHANES) data for 668 postmenopausal women. Logistic regression analysis was conducted to investigate the association of the intakes of B vitamins with hepatic steatosis and liver fibrosis prevalence. The analysis accounted for various covariates and employed restricted cubic spline analysis to examine potential nonlinear relationships. Additionally, interactions among age, diabetes, and B-vitamin intakes, as well as the interaction between folate and vitamin B12 intake, were explored.

Results

Higher intakes of folate [0.30 (0.10-0.88)], choline [0.26 (0.07-0.95)], vitamin B1, and vitamin B2 were associated with a reduced risk of hepatic steatosis in postmenopausal women. The associations of niacin (P-nonlinear = 0.0003), vitamin B1 (P-nonlinear = 0.036), and vitamin B2 (P-nonlinear<0.0001) intakes with hepatic steatosis showed a nonlinear pattern. However, no significant associations were observed between the intakes of niacin, vitamin B6 and vitamin B12 and hepatic steatosis. Furthermore, there were no significant associations between B-vitamin intakes and liver fibrosis. No interaction effects were observed.

Conclusion

Dietary intakes of folate, choline, vitamin B1, and vitamin B2 may be associated with liver steatosis in postmenopausal women, these results suggest that optimizing the intake of these specific B vitamins may have a protective effect against liver steatosis in postmenopausal women, offering valuable insights into potential dietary strategies to promote their well-being.

Relationship between dietary intake components and hepatic fibrosis in those with obesity before and 1 year after bariatric surgery

OBJECTIVES

Non-alcoholic fatty liver disease is highly prevalent in the bariatric population but not all patients develop liver fibrosis. Considering that fibrosis may affect clinical outcomes, it is important to assess and treat contributing factors. In this population, it is not clear whether dietary intake is a contributor. The objective was to determine the relationship between dietary intake components and liver fibrosis before and 1 y after Roux-en-Y gastric bypass (RYGB).

METHODS

This was a prospective cross-sectional (n = 133) study conducted between 2013 and 2022. In addition, a subgroup of 44 patients were followed for 1 y post-RYGB. Anthropometrics, biochemical measurements, and 3-d food records and liver biopsies were obtained presurgery and, in a subgroup of patients, as for the cohort, 1 y post-RYGB.

RESULTS

In the cross-sectional study, 78.2% were female, with a median age of 48 y and body mass index of 46.8 kg/m2; 33.8% had type 2 diabetes mellitus and 57.1% had metabolic syndrome. In a multivariate analysis, age (odds ratio; 95% CI) (1.076; 1.014-1.141), alanine transaminase (1.068; 1.025-1.112), calorie intake (1.001; 1.000-1.002), and dietary copper (0.127; 0.022-0.752) were independently associated with fibrosis (<0.05). At 1 y post-RYGB, no independent risk factors were associated with persistent fibrosis.

CONCLUSIONS

In bariatric patients before surgery, higher age, alanine transaminase, and total calorie and lower copper intakes were independent risk factors associated with liver fibrosis. These relationships were no longer observed after RYGB, likely due to the effect of surgery on weight and similar postsurgery diet among patients.

Alzheimer's Disease-like Pathological Features in the Dorsal Hippocampus of Wild-Type Rats Subjected to Methionine-Diet-Evoked Mild Hyperhomocysteinaemia

Multifactorial interactions, including nutritional state, likely participate in neurodegeneration's pathogenesis and evolution. Dysregulation in methionine (Met) metabolism could lead to the development of hyperhomocysteinaemia (hHcy), playing an important role in neuronal dysfunction, which could potentially lead to the development of Alzheimer's disease (AD)-like pathological features. This study combines proton magnetic resonance spectroscopy (1H MRS) with immunohistochemical analysis to examine changes in the metabolic ratio and histomorphological alterations in the dorsal rat hippocampus (dentate gyrus-DG) subjected to a high Met diet. Male Wistar rats (420-480 g) underwent hHcy evoked by a Met-enriched diet (2 g/kg of weight/day) lasting four weeks. Changes in the metabolic ratio profile and significant histomorphological alterations have been found in the DG of hHcy rats. We have detected increased morphologically changed neurons and glial cells with increased neurogenic markers and apolipoprotein E positivity parallel with a diminished immunosignal for the N-Methyl-D-Aspartate receptor 1 in hHcy animals. A Met diet induced hHcy, likely via direct Hcy neurotoxicity, an interference with one carbon unit metabolism, and/or epigenetic regulation. These conditions lead to the progression of neurodegeneration and the promotion of AD-like pathological features in the less vulnerable hippocampal DG, which presents a plausible therapeutic target.

Serum folate associated with nonalcoholic fatty liver disease and advanced hepatic fibrosis

The role played by serum folate in the progression of nonalcoholic fatty liver disease (NAFLD) remains controversial. The purpose of this study was to investigate the association of serum folate with NAFLD and advanced liver fibrosis (AHF). We conducted a cross-sectional study with 5417 participants using 2011-2018 NHANES data. Multiple logistic regression analysis and propensity score matching analysis were used to investigate the association of serum folate with NAFLD and AHF. In the completely adjusted model, participants in the high serum folate group had a 27% (OR 0.73, 95% CI 0.62, 0.87, p = 0.0003) and 53% (OR 0.47, 95% CI 0.35, 0.63, p < 0.0001) lower odds of suffering from NAFLD and AHF, respectively, compared to the low serum folate group. The similar results in propensity score matching further validated the above association. Stratified analysis showed that the negative correlation of serum folate with NAFLD and AHF demonstrated a broad consistency across populations. The results of this study indicate that higher serum folate level was associated with lower odds of NAFLD and AHF among US adults. Further prospective studies are necessary due to the limitations of cross-sectional studies.

Advances in the role of epigenetics in homocysteine-related diseases

Homocysteine has a wide range of biological effects. However, the specific molecular mechanism of its pathogenicity is still unclear. The diseases induced by hyperhomocysteinemia (HHcy) are called homocysteine-related diseases. Clinical treatment of HHcy is mainly through folic acid and B-complex vitamins, which are not effective in reducing the associated end point events. Epigenetics is the alteration of heritable genes caused by DNA methylation, histone modification, noncoding RNAs and chromatin remodeling without altering the DNA sequence. In recent years the role of epigenetics in homocysteine-associated diseases has been gradually discovered. This article summarizes the latest evidence on the role of epigenetics in HHcy, providing new directions for its prevention and treatment.

Autophagy in homocysteine‑induced HUVEC senescence

The senescence of vascular endothelial cells (VECs) drives the occurrence and development of cardiovascular disease (CVD). Homocysteine (HCY) is a general risk factor for age-associated CVDs. Autophagy, an evolutionarily conserved lysosomal protein degradation pathway, serves a part in VEC senescence. The purpose of this study was to investigate the role of autophagy in HCY-induced endothelial cell senescence and explore novel mechanisms and therapeutic approaches for related CVDs. Human umbilical vein endothelial cells (HUVECs) were isolated from fresh umbilical cords of healthy pregnancies. Cell Counting Kit-8, flow cytometry and senescence-associated (SA) β-galactosidase (Gal) staining demonstrated that HCY induced HUVEC senescence by decreasing cell proliferation, arresting cell cycle and increasing the number of SA-β-Gal-positive cells. Stub-RFP-Sens-GFP-LC3 autophagy-related double fluorescence lentivirus revealed that HCY increased autophagic flux. Further, inhibition of autophagy using 3-methyladenine increased HCY-induced HUVEC senescence. By contrast, the induction of autophagy via rapamycin alleviated HCY-induced HUVEC senescence. Finally, the detection of reactive oxygen species (ROS) with ROS kit showed that HCY increased intracellular ROS, whereas induction of autophagy reduced intracellular ROS. In conclusion, HCY increased HUVEC senescence and upregulated autophagy; moderate autophagy could reverse HCY-induced cell senescence. Autophagy may alleviate HCY-induced cell senescence by decreasing intracellular ROS. This provides insight into the underlying mechanism of HCY-induced VEC senescence and potential treatments for age-associated CVDs.

Can Nutritional Supplements Benefit Patients With Nonalcoholic Steatohepatitis and Nonalcoholic Fatty Liver Disease?

A characteristic of nonalcoholic fatty liver disease (NAFLD) is the buildup of excess fat in the liver which encompasses various clinical phases, including steatosis, inflammation, ballooning, fibrosis, and liver cirrhosis. Nonalcoholic steatohepatitis (NASH) represents a severe form of NAFLD. The prevalence of NAFLD, particularly NASH, is notably high among Hispanics and those with morbid obesity. Diabetes, obesity, and dyslipidemia are significant risk factors in patients with NAFLD. The pathogenesis of NAFLD involves complex interactions between hormonal, nutritional, and genetic factors. Different clinical trials have been conducted to determine if there are any supplements that could help patients with NASH. Evidence has shown that vitamin E decreased the NAFLD activity score but not fibrosis. Our review summarizes the influence of supplementation on patients with NAFLD and NASH, focusing on the use of different clinical trials, systematic reviews, and meta-analyses. In the future, patients and physicians will play crucial roles in exploring diverse approaches and finding effective solutions to address this growing issue.

Effects of Folic Acid Supplementation on Liver Enzymes, Lipid Profile, and Insulin Resistance in Patients with Non-Alcoholic Fatty Liver Disease: A Randomized Controlled Trial

Background

Previous evidence revealed an association between folate deficiency and non-alcoholic fatty liver disease (NAFLD). This study is the first one investigating the effects of folic acid on hepatic steatosis grade, liver enzymes, insulin resistance, and lipid profile in NAFLD cases.

Materials and Methods

Sixty-six participants with NAFLD were allocated randomly to take either a placebo or one oral tablet of folic acid (1 mg) on a daily basis within eight weeks. Serum folate, homocysteine, glucose, aminotransferases, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), and lipids were assessed. Ultrasonography was used for assessing the liver steatosis grade.

Results

The serum alanine transaminase, grade of hepatic steatosis, and aspartate transaminase significantly were decreased within both study groups; however, the between-group comparison was not statistically significant. Of note, the decrease in ALT was more pronounced in folic acid compared with the placebo group (-5.45 ± 7.45 vs. -2.19 ± 8.6 IU/L). The serum homocysteine was decreased after receiving folic acid compared to the placebo (-0.58 ± 3.41 vs. +0.4 ± 3.56 μmol/L; adjusted P = 0.054). Other outcomes did not significantly change.

Conclusion

Supplementation with folic acid (1 mg/d) for eight weeks among cases with NAFLD did not change significantly the serum levels of liver enzymes, the hepatic steatosis grade, insulin resistance and lipid profile. However, it was able to prevent the increase in homocysteine in comparison with the placebo. Conducting further research is suggested with the longer duration and different doses of folic acid, adjusted to the genotypes of methylenetetrahydrofolate reductase polymorphism, among NAFLD patients.

Autophagy: A Cellular Guardian against Hepatic Lipotoxicity

Lipotoxicity is a phenomenon of lipid-induced cellular injury in nonadipose tissue. Excess of free saturated fatty acids (SFAs) contributes to hepatic injury in nonalcoholic fatty liver disease (NAFLD), which has been growing at an unprecedented rate in recent years. SFAs and their derivatives such as ceramides and membrane phospholipids have been shown to induce intrahepatic oxidative damage and ER stress. Autophagy represents a cellular housekeeping mechanism to counter the perturbation in organelle function and activation of stress signals within the cell. Several aspects of autophagy, including lipid droplet assembly, lipophagy, mitophagy, redox signaling and ER-phagy, play a critical role in mounting a strong defense against lipotoxic lipid species within the hepatic cells. This review provides a succinct overview of our current understanding of autophagy-lipotoxicity interaction and its pharmacological and nonpharmacological modulation in treating NAFLD.

Busting the myth of methotrexate chronic hepatotoxicity

Methotrexate is a key component of the treatment of inflammatory rheumatic diseases and the mainstay of therapy in rheumatoid arthritis. Hepatotoxicity has long been a concern for prescribers envisaging long-term treatment with methotrexate for their patients. However, the putative liver toxicity of methotrexate should be evaluated in the context of advances in our knowledge of the pathogenesis and natural history of liver disease, especially non-alcoholic fatty liver disease (NAFLD). Notably, patients with NAFLD are at increased risk for methotrexate hepatotoxicity, and methotrexate can worsen the course of NAFLD. Understanding the mechanisms of acute hepatotoxicity can facilitate the interpretation of elevated concentrations of liver enzymes in this context. Liver fibrosis and the mechanisms of fibrogenesis also need to be considered in relation to chronic exposure to methotrexate. A number of non-invasive tests for liver fibrosis are available for use in patients with rheumatic disease, in addition to liver biopsy, which can be appropriate for particular individuals. On the basis of the available evidence, practical suggestions for pretreatment screening and long-term monitoring of methotrexate therapy can be made for patients who have (or are at risk for) chronic liver disease.