Role of vitamin E in nonalcoholic fatty liver disease

NAFLD-associated hepatocellular carcinoma (HCC) - A compelling case for repositioning of existing mTORc1 inhibitors

The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) is a growing concern for the high incidence rate of hepatocellular carcinoma (HCC) globally. The progression of NAFLD to HCC is heterogeneous and non-linear, involving intermediate stages of non-alcoholic steatohepatitis (NASH), liver fibrosis, and cirrhosis. There is a high unmet clinical need for appropriate diagnostic, prognostic, and therapeutic options to tackle this emerging epidemic. Unfortunately, at present, there is no validated marker to identify the risk of developing HCC in patients suffering from NAFLD or NASH. Additionally, the current treatment protocols for HCC don't differentiate between viral infection or NAFLD-specific etiology of the HCC and have a limited success rate. The mammalian target of rapamycin complex 1 (mTORc1) is an important protein involved in many vital cellular processes like lipid metabolism, glucose homeostasis, and inflammation. These cellular processes are highly implicated in NAFLD and its progression to severe liver manifestations. Additionally, hyperactivation of mTORc1 is known to promote cell proliferation, which can contribute to the genesis and progression of tumors. Many mTORc1 inhibitors are being evaluated for different types of cancers under various phases of clinical trials. This paper deliberates on the strong pathological implication of the mTORc1 signaling pathway in NAFLD and its progression to NASH and HCC and advocates for a systematic investigation of known mTORc1 inhibitors in suitable pre-clinical models of HCC having NAFLD/NASH-specific etiology.

The Impact of Japanese Dietary Patterns on Metabolic Dysfunction-Associated Steatotic Liver Disease and Liver Fibrosis

This study aimed to investigate the effect of Japanese dietary patterns on metabolic dysfunction-associated steatotic liver disease (MASLD) and liver fibrosis. After excluding factors affecting the diagnosis of hepatic steatosis, 727 adults were analyzed as part of the Health Promotion Project. The dietary patterns of the participants were classified into rice, vegetable, seafood, and sweet based on their daily food intake. Liver stiffness measurements and controlled attenuation parameters were performed using FibroScan. Energy and nutrient intake were calculated using the Brief-type Self-administered Diet History Questionnaire. Univariate and multivariate analyses were used to identify the risk factors for liver fibrosis within the MASLD population. The vegetable group had significantly lower liver fibrosis indicators in the MASLD population than the rice group. The multivariate analysis identified a body mass index ≥ 25 kg/m2 (odds ratio [OR], 1.83; 95% confidence interval [CI], 1.01-1.83; p = 0.047) and HOMA-IR ≥ 1.6 (OR, 3.18; 95% CI, 1.74-5.78; p < 0.001) as risk factors for liver fibrosis, and vegetable group membership was a significant low-risk factor (OR, 0.38; 95% CI, 0.16-0.88; p = 0.023). The multivariate analysis of nutrients in low-risk foods revealed high intake of α-tocopherol (OR, 0.74; 95% CI, 0.56-0.99; p = 0.039) as a significant low-risk factor for liver fibrosis. This study suggests that a vegetable-based Japanese dietary pattern, through the antioxidant effects of α-tocopherol, may help prevent liver fibrosis in MASLD and the development of MASLD.

Effects of Combined Low-Dose Spironolactone Plus Vitamin E versus Vitamin E Monotherapy on Lipidomic Profile in Non-Alcoholic Fatty Liver Disease: A Post Hoc Analysis of a Randomized Controlled Trial

Background/Objectives: Lipid dysmetabolism seems to contribute to the development and progression of nonalcoholic fatty liver disease (NAFLD). Our aim was to compare serum lipidomic profile between patients with NAFLD having received monotherapy with vitamin E (400 IU/d) and those having received combination therapy with vitamin E (400 IU/d) and low-dose spironolactone (25 mg/d) for 52 weeks. Methods: This was a post hoc study of a randomized controlled trial (NCT01147523). Serum lipidomic analysis was performed in vitamin E monotherapy group (n = 15) and spironolactone plus vitamin E combination therapy group (n = 12). We employed an untargeted liquid chromatography-mass spectrometry lipid profiling approach in positive and negative ionization mode. Results: Univariate analysis revealed 36 lipid molecules statistically different between groups in positive mode and seven molecules in negative mode. Multivariate analysis in negative mode identified six lipid molecules that remained robustly different between groups. After adjustment for potential confounders, including gender, omega-3 supplementation, leptin concentration and homeostasis model assessment-insulin resistance (HOMA-IR), four lipid molecules remained significant between groups: FA 20:5, SM 34:2;O2, SM 42:3;O2 and CE 22:6, all being higher in the combination treatment group. Conclusions: The combination of spironolactone with vitamin E led to higher circulating levels of four lipid molecules than vitamin E monotherapy, after adjustment for potential confounders. Owing to very limited relevant data, we could not support that these changes in lipid molecules may be beneficial or not for the progression of NAFLD. Thus, mechanistic studies are warranted to clarify the potential clinical significance of these findings.

Redefining the Role of Ornithine Aspartate and Vitamin E in Metabolic-Dysfunction-Associated Steatotic Liver Disease through Its Biochemical Properties

It is known that the inflammation process leading to oxidative stress and thyroid hormone metabolism dysfunction is highly altered in metabolic dysfunction associated with steatotic liver disease (MASLD). This study aims to address the effect of ornithine aspartate (LOLA) and vitamin E (VitE) in improving these processes. Adult Sprague-Dawley rats were assigned to five groups and treated for 28 weeks: controls (n = 10) received a standard diet (for 28 weeks) plus gavage with distilled water (DW) from weeks 16 to 28. MASLD groups received a high-fat and choline-deficient diet for 28 weeks (MASLD group) and daily gavage with 200 mg/kg/day of LOLA, or twice a week with 150 mg of VitE from weeks 16-28. LOLA diminished collagen deposition (p = 0.006). The same treatment diminished carbonyl, TBARS, and sulfhydryl levels and GPx activity (p < 0.001). Type 3 deiodinase increased in the MASLD group, downregulating T3-controlled genes, which was corrected in the presence of LOLA. LOLA also promoted a near-normalization of complex II, SDH, and GDH activities (p < 0.001) and improved reticulum stress, with a reduction in GRP78 and HSPA9/GRP75 protein levels (p < 0.05). The enhanced energy production and metabolism of thyroid hormones, probably because of GSH replenishment provided by the L-glutamate portion of LOLA, opens a new therapeutic approach for MASLD.

Association between the composite dietary antioxidant index and metabolic dysfunction-associated steatotic liver disease in adults: a cross-sectional study from NHANES 2017-2020

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as a predominant liver disease worldwide, lacking approved drugs for clinical intervention at present. The composite dietary antioxidant index (CDAI) is used to assess the anti-inflammatory properties of diets, with higher CDAI indicating greater exposure to antioxidants. Therefore, our study aimed to explore the relationship between CDAI and MASLD in order to identify potential therapeutic approaches. We collected data from 12,286 participants in the National Health and Nutrition Examination Survey (NHANES) database from 2017 to 2020 for analysis. The correlation between CDAI and MASLD status, controlled attenuation parameter (CAP), and liver stiffness measurement (LSM) was evaluated by adjusting for confounding variables using weighted binary logistic regression model, linear regression model, and restricted cubic spline (RCS) regression. The median CDAI in this study was - 0.3055 (interquartile range [IQR], - 2.299 to 2.290). The CDAI was higher in the population characterized by being young, female, higher income, absence of diabetes, and non-MASLD. After multivariable adjustment, the results of the weighted linear regression model suggested that higher CDAI may be associated with a decrease in CAP values; the results of the RCS regression model indicated significant non-linear relationships between MASLD status, CAP, LSM, and CDAI. The CDAI corresponding to the inflection points of the relationship curves between MASLD status, CAP, LSM, and CDAI were 0.349, 0.699, and 0.174, respectively. After further stratification by gender, we found that the relationship between MASLD status, CAP, and CDAI was significantly linear for females, whereas for males, it was non-linear, and the CDAI values corresponding to the inflection points in the curves for males were 1.325 and 0.985, respectively. We found that higher CDAI may be associated with decreased CAP values, particularly significant in females, suggesting that the intake of complex dietary antioxidants may ameliorate hepatic steatosis and reduce the occurrence of MASLD. Therefore, promoting dietary patterns rich in antioxidants may be an appropriate strategy to reduce the incidence of MASLD.

Non-alcoholic fatty liver disease changes the expression and activity of hepatic drug-metabolizing enzymes and transporters in rats

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases, which can cause serious complications and gradually increase the mortality rate. However, the effects of NAFLD on drug-metabolizing enzymes and transporters remain unclear, which may cause some confusion regarding patient medication. In this study, a NAFLD rat model was constructed by feeding rats with methionine and choline deficiency diets for 6 weeks, and the mRNA and protein levels of drug-metabolizing enzymes and transporter were analyzed by real-time fluorescent quantitative PCR and Western blot, respectively. The activity of drug-metabolizing enzymes was detected by cocktail methods. In the NAFLD rat model, the mRNA expression of phase I enzymes, phase II enzymes, and transporters decreased. At the protein level, only CYP1A1, CYP1B1, CYP2C11, and CYP2J3 presented a decrease. In addition, the activities of CYP1A2, CYP2B1, CYP2C11, CYP2D1, CYP3A2, UGT1A1, UGT1A3, UGT1A6, and UGT1A9 decreased. These changes may be caused by the alteration of FXR, HNF4α, LXRα, LXRβ, PXR, and RXR. In conclusion, NAFLD changes the expression and activity of hepatic drug-metabolizing enzymes and transporters in rats, which may affect drug metabolism and pharmacokinetics. In clinical medication, drug monitoring should be strengthened to avoid potential risks.

Dietary macro and micronutrients associated with MASLD: Analysis of a national US cohort database

INTRODUCTION AND OBJECTIVES

Our objective was to measure and compare the intake of macro and micronutrients in a cohort of individuals with Metabolic Syndrome Associated Steatotic Liver Disease (MASLD) compared with matched controls to identify areas of further research in this area; we identified nutrition-associated associations with MASLD in the United States general population.

MATERIALS AND METHODS

We used the 2017 - 2018 NHANES dataset. Elastography Controlled Attenuation Parameter (CAP score>280) in the absence of other liver disease was defined as MASLD in adults (>18). Advanced fibrosis was defined by transient elastography >10 kPa. Controls were adults without liver disease.

RESULTS

1648 MASLD cases (11.4 % advanced fibrosis) and 2527 controls were identified. MASLD cases were older (P<0.001), more likely males (P = 0.01), less likely to have a college education (P = 0.04) and more likely married (P = 0.002). MASLD cases were more likely to be of Mexican American or Hispanic ethnicity (P = 0.002), have higher BMI, and have higher prevalence of diabetes, hyperlipidemia and hypertension (P<0.001 for all). MASLD cases had higher hs-CRP (P = 0.02) and ferritin (P = 0.02). MASLD cases had lower total (P = 0.004) and added vitamin E in their diet (P = 0.002), lower vitamin K intake (P = 0.005), and higher selenium intake (P = 0.03). Caloric intake (P = 0.04), carbohydrate intake (P = 0.02), cholesterol intake (P = 0.03) and saturated fatty acid intake (P = 0.05) were higher in MASLD. Individuals with MASLD were more likely to be on a diet (P<0.001), sedentary (P = 0.008) and less likely to participate in moderate or vigorous recreational activities (P<0.001).

CONCLUSIONS

The deficiencies of micronutrients and excess of macronutrients point to oxidative stress, pro-inflammatory state, and lipotoxicity as pathways linking the US diet to MASLD. MASLD patients are more often on special diets, which may reflect prior provider counseling on diet changes to improve health.

Dietary characteristics associated with the risk of non-alcoholic fatty liver disease and metabolic dysfunction-associated steatotic liver disease in non-obese Japanese participants: A cross-sectional study

Background and Aim

Dietary characteristics associated with non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD) in non-obese patients remain to be elucidated. This study examined the association of NAFLD and MASLD with dietary characteristics according to obesity status.

Methods

We performed a cross-sectional study of 15 135 participants (n = 7568 men and 7567 women) aged 35-74 years using data of annual health checks between 2008 and 2020. Obesity was defined as BMI ≥ 25 kg/m2. Diagnosis of fatty liver was based on abdominal ultrasonography. Fatty-liver-related dietary characteristics were assessed using a self-administered questionnaire.

Results

For non-obese participants, NAFLD was found in 31.0% of men and 19.4% of women. Non-obese MASLD was found in 27.6% of men and 18.1% of women. Multivariable-adjusted stepwise logistic regression analysis indicated that, in males, both non-obese NAFLD and non-obese MASLD were significantly and negatively associated with "often eat sesame/nuts", and positively associated with "often eat noodles/rice bowl" and "often eat evening meal" (P < 0.05). For non-obese women, both NAFLD and MASLD were significantly and positively associated with "often eat sweet buns/bread with fillings" (P < 0.05). Adjusted analyses showed that all dietary characteristics were not significantly associated with the risk of NAFLD/MASLD in obese men and women.

Conclusion

This cross-sectional study indicates the existence of sex and obesity differences in the association of NAFLD and MASLD with dietary characteristics. Our findings suggest that some dietary characteristics are associated with NAFLD and MASLD prevalence in non-obese Japanese participants.

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.

Methyl Cinnamate (MC) Alleviates Free Fatty Acids (FFAs) Induced Lipid Accumulation Through the AMPK Pathway in HepG2 Cells

Background

AMP-activated protein kinase (AMPK) plays a critical role in energy metabolism. Its activation leads to the phosphorylation of downstream proteins such as acetyl-CoA carboxylase (ACC) and sterol regulatory element-binding protein-1 (SREBP1), subsequently inhibiting de novo fatty acid synthesis, thereby reducing intracellular triglyceride accumulation. MC is a compound found in extracts from Zanthoxylum armatum DC plants. Research has shown that MC can inhibit the differentiation of 3T3-L1 adipocytes through the CAMKK2-AMPK pathway. However, the biological effect of MC in HepG2 cells remains unknown.

Methods

In this study, we utilized HepG2 cells to establish a model of MAFLD through FFAs stimulation. We investigated the biological effects of MC on HepG2 cells and studied its impact on lipid metabolism. Small interfering RNA was employed to explore the mechanism by which MC activates AMPK. Finally, molecular docking was conducted, establishing a model of the interaction between AMPK and MC.

Results

We observed that MC can alleviate triglyceride accumulation in HepG2 cells. We observed the elevated p-AMPK/AMPK, P-ACC/ ACC, and elevated CPT1a after treatment of MC in HepG2 cells. The interference of CAMKK2 mRNA did not impact the ability of MC to phosphorylate AMPK. Compound C attenuates the ability of MC to increase p-AMPK. Molecular docking results led us to hypothesize that MC directly interacts with AMPK, resulting in AMPK phosphorylation and improved lipid accumulation in HepG2 cells.

Association of metabolic-dysfunction associated steatotic liver disease with polycystic ovary syndrome

Non-alcoholic fatty liver disease (NAFLD), which has a prevalence of over 25% in adults, encompasses a wide spectrum of liver diseases. Metabolic-dysfunction associated steatotic liver disease (MASLD), the new term for NAFLD, is characterized by steatotic liver disease accompanied by cardiometabolic criteria, showing a strong correlation with metabolic diseases. Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disease affecting 4-21% of women of reproductive age. Numerous studies have indicated that NAFLD and PCOS often occur together. However, as MASLD is a new term, there is still a lack of reports describing the effects of MASLD on the development of PCOS. In this review article, we have summarized the complex and multifaceted connections between MASLD and PCOS. Understanding the pathogenesis and treatment methods could not only guide the clinical prevention, diagnosis, and treatment of PCOS in patients with MASLD, but also increase the clinical attention of reproductive doctors to MASLD.

Mitochondrial Dysfunction in Metabolic Dysfunction Fatty Liver Disease (MAFLD)

Nonalcoholic fatty liver disease (NAFLD) has become an increasingly common disease in Western countries and has become the major cause of liver cirrhosis or hepatocellular carcinoma (HCC) in addition to viral hepatitis in recent decades. Furthermore, studies have shown that NAFLD is inextricably linked to the development of extrahepatic diseases. However, there is currently no effective treatment to cure NAFLD. In addition, in 2020, NAFLD was renamed metabolic dysfunction fatty liver disease (MAFLD) to show that its pathogenesis is closely related to metabolic disorders. Recent studies have reported that the development of MAFLD is inextricably associated with mitochondrial dysfunction in hepatocytes and hepatic stellate cells (HSCs). Simultaneously, mitochondrial stress caused by structural and functional disorders stimulates the occurrence and accumulation of fat and lipo-toxicity in hepatocytes and HSCs. In addition, the interaction between mitochondrial dysfunction and the liver-gut axis has also become a new point during the development of MAFLD. In this review, we summarize the effects of several potential treatment strategies for MAFLD, including antioxidants, reagents, and intestinal microorganisms and metabolites.

Gut microbiota bridges dietary nutrients and host immunity

Dietary nutrients and the gut microbiota are increasingly recognized to cross-regulate and entrain each other, and thus affect host health and immune-mediated diseases. Here, we systematically review the current understanding linking dietary nutrients to gut microbiota-host immune interactions, emphasizing how this axis might influence host immunity in health and diseases. Of relevance, we highlight that the implications of gut microbiota-targeted dietary intervention could be harnessed in orchestrating a spectrum of immune-associated diseases.

Mechanisms Behind NAFLD: a System Genetics Perspective

PURPOSE OF REVIEW

To summarize the key factors contributing to the onset and progress of nonalcoholic fatty liver disease (NAFLD) and put them in a system genetics context. We particularly focus on how genetic regulation of hepatic lipids contributes to NAFLD.

RECENT FINDINGS

NAFLD is characterized by excessive accumulation of fat in the liver. This can progress to steatohepatitis (inflammation and hepatocyte injury) and eventually, cirrhosis. The severity of NAFLD is determined by a combination of factors including obesity, insulin resistance, and lipotoxic lipids, along with genetic susceptibility. Numerous studies have been conducted on large human cohorts and mouse panels, to identify key determinants in the genome, transcriptome, proteome, lipidome, microbiome and different environmental conditions contributing to NAFLD. We review common factors contributing to NAFLD and put them in a systems genetics context. In particular, we describe how genetic regulation of liver lipids contributes to NAFLD. The combination of an unhealthy lifestyle and genetic predisposition increases the likelihood of accumulating lipotoxic specie lipids that may be one of the driving forces behind developing severe forms of NAFLD.

The Potential Role of C-Reactive Protein in Metabolic-Dysfunction-Associated Fatty Liver Disease and Aging

Nonalcoholic fatty liver disease (NAFLD), recently redefined as metabolic-dysfunction-associated fatty liver disease (MASLD), is liver-metabolism-associated steatohepatitis caused by nonalcoholic factors. NAFLD/MASLD is currently the most prevalent liver disease in the world, affecting one-fourth of the global population, and its prevalence increases with age. Current treatments are limited; one important reason hindering drug development is the insufficient understanding of the onset and pathogenesis of NAFLD/MASLD. C-reactive protein (CRP), a marker of inflammation, has been linked to NAFLD and aging in recent studies. As a conserved acute-phase protein, CRP is widely characterized for its host defense functions, but the link between CRP and NAFLD/MASLD remains unclear. Herein, we discuss the currently available evidence for the involvement of CRP in MASLD to identify areas where further research is needed. We hope this review can provide new insights into the development of aging-associated NAFLD biomarkers and suggest that modulation of CRP signaling is a potential therapeutic target.

Vitamin E and Pioglitazone: A Comprehensive Systematic Review of Their Efficacy in Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is becoming increasingly prevalent worldwide, especially in people with obesity, dyslipidemia, type 2 diabetes mellitus (T2DM), and metabolic syndrome. Weight loss and dietary modifications are established first-line treatments for NAFLD. Currently, there is no approved drug for NAFLD; however, pioglitazone and vitamin E have shown some beneficial effects. This systematic review covers the comparative efficacies of vitamin E, pioglitazone, and vitamin E plus pioglitazone. As of December 2022, the sources for prior literature review included PubMed, PubMed Central, and Medline. We included studies assessing the efficacy of pioglitazone, vitamin E, and vitamin E plus pioglitazone in improving liver histology, liver markers, and lipid profile when compared to other interventions in patients with NAFLD/non-alcoholic steatohepatitis (NASH). Review materials include randomized control trials (RCTs), traditional reviews, systematic reviews, meta-analyses, and observational studies on human participants published within the last five years in the English language. Studies on animals, pediatric populations, and with insufficient data were excluded from the review. Two authors scanned and filtered articles independently and later performed quality checks. A third reviewer resolved any conflicts. The risk of bias was assessed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines for systematic reviews, the Cochrane Risk of Bias Tool for RCTs, and the Scale for the Assessment of Narrative Review Articles for Traditional Reviews. A total of 21 articles were shortlisted. The results showed that pioglitazone and vitamin E are effective in reducing steatosis, inflammation, and ballooning, reducing liver markers, but there seem to be conflicting data on fibrosis resolution. Pioglitazone decreases triglycerides and increases high-density lipoproteins. One study has suggested that pioglitazone has superior efficacy to vitamin E in fibrosis reduction and vitamin E plus pioglitazone has superior efficacy than pioglitazone alone for NASH resolution. However, these conclusions require further validation through extensive analysis and additional research. In conclusion, diabetic patients with NAFLD can be given pioglitazone, and non-diabetic patients with NAFLD can be given vitamin E.

Oxidative balance score is inversely associated with the incidence of non-alcoholic fatty liver disease

BACKGROUND & AIMS

The contribution of the balance between overall oxidative stress and antioxidant status in non-alcoholic fatty liver disease (NAFLD) is unclear. The oxidative balance score (OBS) comprises dietary and lifestyle pro- and antioxidant components that indicate the overall oxidative stress burden. We investigated the association between OBS and the incidence of NAFLD in middle-aged and older Korean adults.

METHODS

Among the 10,030 participants of the Korean Genome and Epidemiology Study_Ansan and Ansung cohort, 5065 without NAFLD at baseline were selected for secondary analysis. OBS was categorized into quartiles. Multiple Cox proportional hazard regression analyses were performed to estimate the hazard ratio (HR) and 95% confidence interval (CI) for NAFLD incidence by sex-specific OBS quartile groups after adjusting for confounders.

RESULTS

During the follow-up period (median 13.4 years), 913 (43.2%) men and 1288 (43.9%) women were newly diagnosed with NAFLD. Compared with that of the lowest quartile (Q1) group, the adjusted HR (95% CI) for NAFLD incidence in Q2, Q3, and Q4 groups was 0.85 (0.71-1.00), 0.65 (0.54-0.78), and 0.50 (0.40-0.62) in men, and 0.85 (0.73-0.99), 0.66 (0.56-0.77), and 0.48 (0.40-0.59) in women, respectively, and for NAFLD incidence, per incremental change in OBS, was 0.90 (0.87-0.92) in men and 0.88 (0.86-0.90) in women.

CONCLUSIONS

A higher OBS was significantly associated with a lower risk for NAFLD incidence. Maintaining a healthy lifestyle and an antioxidant-rich diet is a potentially viable strategy for preventing NAFLD.

Vitamin E supplementation in the treatment on nonalcoholic fatty liver disease (NAFLD): Evidence from an umbrella review of meta-analysis on randomized controlled trials

OBJECTIVE

We conducted this umbrella review of meta-analysis on randomized controlled trials to clarify the effects of vitamin E administration on alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), degrees of steatosis and fibrosis in patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

PubMed, MEDLINE, SCOPUS, EMBASE, and Web of Science were searched to identify pertinent articles published up to June 2023. To calculate the overall effect size (ES) and confidence intervals (CI), random-effects model was used.

RESULTS

Six meta-analyses were included in the umbrella review. By pooling ES based on the random-effects model, we found that vitamin E supplementation significantly decreased ALT (ES -6.47, 95% CI -11.73 to -1.22, P = 0.01), AST (ES -5.35, 95% CI -9.78 to -0.93, P = 0.01), degrees of fibrosis (ES -0.24, 95% CI -0.36 to -0.12, P < 0.001) and steatosis (ES -0.67, 95% CI -0.88 to -0.45, P < 0.001) in NAFLD patients, but had no effect on GGT. In the subgroup analyses, we detected that fibrosis scores notably decreased when vitamin E dosage was >600 IU/day (ES -0.25, 95% CI -0.41 to -0.10, P = 0.002) and when the treatment duration was ≥12 months (ES -0.24, 95% CI -0.37 to -0.12, P < 0.001).

CONCLUSION

Vitamin E administration improves ALT, AST, fibrosis, and steatosis in NAFLD subjects. Fibrosis scores were significantly reduced when vitamin E dosage exceeded 600 IU/day or with a treatment duration of at least 12 months.

Effect of Nut Consumption on Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

Although previous epidemiological studies have been conducted to investigate the relationship between nut consumption and the risk of nonalcoholic fatty liver disease (NAFLD), the evidence remains inconclusive and contentious. The aim of our study was to further conduct a meta-analysis of observational studies to explore the latest evidence of the influence of nut consumption on NAFLD. This meta-analysis included a comprehensive search of all articles published in the PubMed and Web of Science online databases as of April 2023. A total of 11 articles were included, comprising 2 prospective cohort studies, 3 cross-sectional studies, and 7 case-control studies, and a random effects model was used to evaluate the relationship between nuts and NAFLD. Results showed that the odds ratio (OR) of NAFLD was 0.90 (95% CI: 0.81-0.99, p < 0.001) when comparing the highest and lowest total nut intake, indicating a significant negative correlation. Furthermore, subgroup analysis revealed that the protective effect of nuts on NAFLD was more significant in females (OR = 0.88; 95% CI: 0.78-0.98, I² = 76.2%). In summary, our findings provide support for a protective relationship between nut intake and risk of NAFLD. Further exploration of the association between other dietary components and NAFLD is an important avenue for future research.

Targeting ferroptosis, a novel programmed cell death, for the potential of alcohol-related liver disease therapy

Ferroptosis is a new iron-dependent cell death mode, which is different from the other types of programmed cell death, such as apoptosis, necrosis, and autophagy. Ferroptosis is characterized by a process in which fatal lipids from lipid peroxidation accumulate in cells and eventually lead to cell death. Alcohol-related liver disease (ALD) is a type of liver injury caused by excessive alcohol intake. Alcohol-related liver disease is a broad-spectrum disease category, which includes fatty liver, steatohepatitis, hepatitis, cirrhosis, and hepatocellular tumors. Recent studies have found that ferroptosis is involved in the pathological development of non-viral liver diseases. Therefore, ferroptosis may be an ideal target for the treatment of non-viral liver diseases. In this review article, we will elaborate the molecular mechanism and regulatory mechanism of ferroptosis, explore the key role of ferroptosis in the Alcohol-related liver disease process, and summarize the existing targeted ferroptosis drugs and their feasibility for the treatment of Alcohol-related liver disease.

The relationship between vitamin K and metabolic dysfunction-associated fatty liver disease among the United States population: National Health and Nutrition Examination Survey 2017-2018

Background

The effect of vitamin K is associated with several pathological processes in fatty liver. However, the association between vitamin K levels and metabolic dysfunction-associated fatty liver disease (MAFLD) remains unclear.

Objective

Here, we investigated the relationship between vitamin K intake and MAFLD risk by employing the American National Health and Nutrition Examination Surveys (NHANES) including 3,571 participants.

Methods

MAFLD was defined as hepatic steatosis with one or more of the following: overweight or obesity, type 2 diabetes, or >2 other metabolic risk abnormalities. The total vitamin K was the sum of dietary and supplement dietary intake. The relationship of between log₁₀(vitamin K) and MAFLD was investigated using survey-weighted logistic regression and stratified analysis, with or without dietary supplementation.

Results

The MAFLD population had a lower vitamin K intake than the non-MAFLD population (p = 0.024). Vitamin K levels were inversely associated with MAFLD in the fully adjusted model (OR = 0.488, 95% CI: 0.302-0.787, p = 0.006). Consistent results were seen in the group without dietary supplements (OR = 0.373, 95% CI: 0.186-0.751, p = 0.009) but not in the group consuming dietary supplements (OR = 0.489, 95% CI: 0.238-1.001, p = 0.050).

Conclusion

Vitamin K intake may be a protective factor for MAFLD, especially for individual not using dietary supplements. Nevertheless, more high-quality prospective studies are needed to clarify the causal relationship between them.

The Effect of Bioactive Aliment Compounds and Micronutrients on Non-Alcoholic Fatty Liver Disease

In the current review, we focused on identifying aliment compounds and micronutrients, as well as addressed promising bioactive nutrients that may interfere with NAFLD advance and ultimately affect this disease progress. In this regard, we targeted: 1. Potential bioactive nutrients that may interfere with NAFLD, specifically dark chocolate, cocoa butter, and peanut butter which may be involved in decreasing cholesterol concentrations. 2. The role of sweeteners used in coffee and other frequent beverages; in this sense, stevia has proven to be adequate for improving carbohydrate metabolism, liver steatosis, and liver fibrosis. 3. Additional compounds were shown to exert a beneficial action on NAFLD, namely glutathione, soy lecithin, silymarin, Aquamin, and cannabinoids which were shown to lower the serum concentration of triglycerides. 4. The effects of micronutrients, especially vitamins, on NAFLD. Even if most studies demonstrate the beneficial role of vitamins in this pathology, there are exceptions. 5. We provide information regarding the modulation of the activity of some enzymes related to NAFLD and their effect on this disease. We conclude that NAFLD can be prevented or improved by different factors through their involvement in the signaling, genetic, and biochemical pathways that underlie NAFLD. Therefore, exposing this vast knowledge to the public is particularly important.

Silymarin for treatment of adults with nonalcoholic fatty liver disease

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To evaluate the benefits and harms of silymarin in adults with nonalcoholic fatty liver disease (NAFLD).

[State of the art on the pathophysiology, diagnosis and treatment of non-alcoholic steatohepatitis (NASH)]

NAFLD or non-alcoholic fatty liver disease is one of the complications of obesity and diabetes, the prevalence of which is increasing. The causes of the pathology and its development towards its severe form, NASH or non-alcoholic steatohepatitis, are multiple and still poorly understood. Many different pharmacological classes are being tested in clinical trials to treat NASH, but no pharmaceutical treatment is currently on the market. Moreover, the diagnosis of certainty is only possible by liver biopsy and histological analysis, an invasive procedure with high risk for the patient. It is therefore necessary to better understand the natural history of the disease in order to identify therapeutic targets, but also to identify markers for the diagnosis and monitoring of the disease using a blood sample, which will allow an improvement in patient management.

Therapeutic interventions of acute and chronic liver disorders: A comprehensive review

Liver disorders are one of the most common pathological problems worldwide. It affects more than 1.5 billion worldwide. Many types of hepatic cells have been reported to be involved in the initiation and propagation of both acute and chronic liver diseases, including hepatocytes, Kupffer cells, sinusoidal endothelial cells, and hepatic stellate cells (HSCs). In addition, oxidative stress, cytokines, fibrogenic factors, microRNAs, and autophagy are also involved. Understanding the molecular mechanisms of liver diseases leads to discovering new therapeutic interventions that can be used in clinics. Recently, antioxidant, anti-inflammatory, anti-HSCs therapy, gene therapy, cell therapy, gut microbiota, and nanoparticles have great potential for preventing and treating liver diseases. Here, we explored the recent possible molecular mechanisms involved in the pathogenesis of acute and chronic liver diseases. Besides, we overviewed the recent therapeutic interventions that targeted liver diseases and summarized the recent studies concerning liver disorders therapy.

Thermogenic Adipose Redox Mechanisms: Potential Targets for Metabolic Disease Therapies

Metabolic diseases, such as diabetes and non-alcoholic fatty liver disease (NAFLD), have several negative health outcomes on affected humans. Dysregulated energy metabolism is a key component underlying the pathophysiology of these conditions. Adipose tissue is a fundamental regulator of energy homeostasis that utilizes several redox reactions to carry out the metabolism. Brown and beige adipose tissues, in particular, perform highly oxidative reactions during non-shivering thermogenesis to dissipate energy as heat. The appropriate regulation of energy metabolism then requires coordinated antioxidant mechanisms to counterbalance the oxidation reactions. Indeed, non-shivering thermogenesis activation can cause striking changes in concentrations of both oxidants and antioxidants in order to adapt to various oxidative environments. Current therapeutic options for metabolic diseases either translate poorly from rodent models to humans (in part due to the challenges of creating a physiologically relevant rodent model) or tend to have numerous side effects, necessitating novel therapies. As increased brown adipose tissue activity results in enhanced energy expenditure and is associated with beneficial effects on metabolic health, such as decreased obesity, it has gathered great interest as a modulator of metabolic disease. One potential reason for the beneficial health effects may be that although non-shivering thermogenesis is enormously oxidative, it is also associated with decreased oxidant formation after its activation. However, targeting its redox mechanisms specifically to alter metabolic disease remains an underexplored area. Therefore, this review will discuss the role of adipose tissue in energy homeostasis, non-shivering thermogenesis in adults, and redox mechanisms that may serve as novel therapeutic targets of metabolic disease.

Ornithine Aspartate and Vitamin-E Combination Has Beneficial Effects on Cardiovascular Risk Factors in an Animal Model of Nonalcoholic Fatty Liver Disease in Rats

Cardiovascular (CV) disease is the main cause of death in nonalcoholic fatty liver disease (NAFLD), a clinical condition without any approved pharmacological therapy. Thus, we investigated the effects of ornithine aspartate (LOLA) and/or Vitamin E (VitE) on CV parameters in a steatohepatitis experimental model. Adult Sprague Dawley rats were randomly assigned (10 animals each) and treated from 16 to 28 weeks with gavage as follows: controls (standard diet plus distilled water (DW)), NAFLD (high-fat choline-deficient diet (HFCD) plus DW), NAFLD+LOLA (HFCD plus LOLA (200 mg/kg/day)), NAFLD+VitE (HFCD plus VitE (150 mg twice a week)) or NAFLD+LOLA+VitE in the same doses. Atherogenic ratios were higher in NAFLD when compared with NAFLD+LOLA+VitE and controls (p < 0.05). Serum concentration of IL-1β, IL-6, TNF-α, MCP-1, e-selectin, ICAM-1, and PAI-1 were not different in intervention groups and controls (p > 0.05). NAFLD+LOLA decreased miR-122, miR-33a, and miR-186 (p < 0.05, for all) in relation to NAFLD. NAFLD+LOLA+VitE decreased miR-122, miR-33a and miR-186, and increased miR-126 (p < 0.05, for all) in comparison to NAFLD and NAFLD+VitE. NAFLD+LOLA and NAFLD+LOLA+VitE prevented liver collagen deposition (p = 0.006) in comparison to NAFLD. Normal cardiac fibers (size and shape) were lower in NAFLD in relation to the others; and the inverse was reported for the percentage of regular hypertrophic cardiomyocytes. NAFLD+LOLA+VitE promoted a significant improvement in atherogenic dyslipidemia, liver fibrosis, and paracrine signaling of lipid metabolism and endothelial dysfunction. This association should be further explored in the treatment of NAFLD-associated CV risk factors.

Diagnostic and therapeutic strategies for non-alcoholic fatty liver disease

The global incidence rate of non-alcoholic fatty liver disease (NAFLD) is approximately 25%. With the global increase in obesity and its associated metabolic syndromes, NAFLD has become an important cause of chronic liver disease in many countries. Despite recent advances in pathogenesis, diagnosis, and therapeutics, there are still challenges in its treatment. In this review, we briefly describe diagnostic methods, therapeutic targets, and drugs related to NAFLD. In particular, we focus on evaluating carbohydrate and lipid metabolism, lipotoxicity, cell death, inflammation, and fibrosis as potential therapeutic targets for NAFLD. We also summarized the clinical research progress in terms of drug development and combination therapy, thereby providing references for NAFLD drug development.

Risk Prevention and Health Promotion for Non-Alcoholic Fatty Liver Diseases (NAFLD)

Non-alcoholic fatty liver disease (NAFLD) is a serious clinicopathological condition that is recognized as the most frequent chronic liver disease, affecting 14–30% of the world’s population. The prevalence of NAFLD has rapidly grown and is correlated with the growth in obesity and type 2 diabetes, among other factors. NAFLD often results in long-term complications including cardiovascular disease, liver cirrhosis, and liver fibrosis. This paper provides an updated overview of NAFLD with a focus on epidemiology, etiology, pathophysiology, screening, complications, and pharmacological therapies to identify effective risk prevention and health promotion.

Exploring the Protective Effects and Mechanism of Huaji Jianpi Decoction against Nonalcoholic Fatty Liver Disease by Network Pharmacology and Experimental Validation

This paper was designed to predict the mechanisms of the active components of Huaji Jianpi Decoction (HJJPD) against nonalcoholic fatty liver disease (NAFLD) based on network pharmacology-combined animal experiments. The candidate compounds of HJJPD and its relative targets were obtained from TCMSP and PharmMapper web server, and the intersection genes for NAFLD were discerned using OMIM, GeneCards, and DisGeNET. Then, the target protein-protein interaction (PPI) and component-target-pathway networks were constructed. Moreover, gene function annotation (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to study the potential signaling pathways associated with HJJPD’s effect on NAFLD. Molecular docking simulation was preformed to validate the binding affinity between potential core components and key targets. Eventually, the candidate targets, the possible pathway, and the mechanism of HJJPD were predicted by the network pharmacology-based strategy, followed by experimental validation in the NAFLD mice model treated with HJJPD. A total of 55 candidate compounds and 36 corresponding genes were identified from HJJPD that are associated with activity against NAFLD, and then the network of them was constructed. Inflammatory response and lipid metabolism-related signaling pathways were identified as the critical signaling pathways mediating the therapeutic effect of the active bioactive ingredients on NAFLD. Compared with the model group, the liver wet weight, liver/body ratio, the levels of total cholesterol (TC), triglyceride (TG), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and high-density lipoprotein (HDL) in serum in the HJJPD low-dose (17.52 g/kg·d), medium-dose (35.04 g/kg·d), and high-dose (70.07 g/kg·d) groups significantly decreased ( $P<0.05$ ). Light microscope observation shows that HJJPD could control the degree of lipid denaturation of the mouse liver tissue to a great extent. RT-qPCR results show that the mRNA expression levels of peroxisome proliferative activated receptor gamma (PPARG), tumor necrosis factor-α (TNF-α), antiserine/threonine protein kinase 1 (AKT1), and prostaglandin-endoperoxide synthase (PTGS2) in the liver tissues of the three HJJPD groups (17.52 g/kg·d, 35.04 g/kg·d, and 70.07 g/kg·d) were significantly lower than those in the model group ( $P<0.05$ ). HJJPD can exert its effect by inhibiting hepatic steatosis and related mRNA expression and decreasing the levels of other liver-related indexes. This study suggested that HJJPD exerted its effect on NAFLD by modulating multitargets with multicompounds through multipathways. It also demonstrated that the network pharmacology-based approach might provide insights for understanding the interrelationship between complex diseases and interventions of HJJPD.

Associations of serum multivitamin levels with the risk of non-alcoholic fatty liver disease: A population-based cross-sectional study in U.S. adults

Vitamins were closely associated with non-alcoholic fatty liver disease (NAFLD) development, but no study had explored the association of serum multivitamin levels with NAFLD risk. We assessed the association between serum levels of both single-vitamin and multivitamins (VA, VB6, VB9, VB12, VC, VD, and VE) and the risk of NAFLD, using the database of National Health and Nutrition Examination Survey (NHANES) (cycles 2003–2004 and 2005–2006). We employed multivariable logistic regression and weighted quantile sum (WQS) regression models to explore the association of serum multivitamin levels with NAFLD. Among all 2,294 participants, 969 participants with NAFLD were more likely to be male, older, less educated, or have hypertension/high cholesterol/diabetes. After adjustment of covariates, serum VC/VD/VB6/VB9 levels were negatively correlated with NAFLD risk, while serum VA/VE levels were positively correlated with NAFLD risk. In the WQS model, elevated serum VA/VE levels and lowered serum VC/VD/VB6 levels were linearly associated with increased NAFLD risk. There was a non-linear relationship between serum VB9/VB12 levels and NAFLD risk. There were evident associations between serum multivitamin levels and reduced NAFLD risk, which was mainly driven by VD/VB9/VC. In conclusion, our findings suggested that serum multivitamin levels were significantly associated with the risk of NAFLD.

Glucocorticosteroids and the Risk of NAFLD in Inflammatory Bowel Disease

Each year, the incidence of nonalcoholic fatty liver (NAFLD) disease increases. NAFLD is a chronic disease. One of the most common causes of NAFLD is an inadequate lifestyle, which is characterized by a lack or low physical activity and eating highly processed foods rich in saturated fat and salt and containing low amount of fiber. Moreover, disturbances in intestinal microbiome and the use of certain drugs may predispose to NAFLD. NAFLD is an increasingly described disease in patients with inflammatory bowel disease (IBD). Recent data also indicate a frequent coexistence of metabolic syndrome in this group of patients. Certain groups of drugs also increase the risk of developing inflammation, liver fibrosis, and cirrhosis. Particularly important in the development of NAFLD are steroids, which are used in the treatment of many diseases, for example, IBD. NAFLD is one of the most frequent parenteral manifestations of the disease in IBD patients. However, there is still insufficient information on what dose and exposure time of selected types of steroids may lead to the development of NAFLD. It is necessary to conduct further research in this direction. Therefore, patients with IBD should be constantly monitored for risk factors for the development of NAFLD.

Hepatocyte Proteome Alterations Induced by Individual and Combinations of Common Free Fatty Acids

Non-alcoholic fatty liver disease is a pathology with a hard-to-detect onset and is estimated to be present in a quarter of the adult human population. To improve our understanding of the development of non-alcoholic fatty liver disease, we treated a human hepatoma cell line model, HepG2, with increasing concentrations of common fatty acids, namely myristic, palmitic and oleic acid. To reproduce more physiologically representative conditions, we also included combinations of these fatty acids and monitored the cellular response with an in-depth proteomics approach and imaging techniques. The two saturated fatty acids initially presented a similar phenotype of a dose-dependent decrease in growth rates and impaired lipid droplet formation. Detailed analysis revealed that the drop in the growth rates was due to delayed cell-cycle progression following myristic acid treatment, whereas palmitic acid led to cellular apoptosis. In contrast, oleic acid, as well as saturated fatty acid mixtures with oleic acid, led to a dose-dependent increase in lipid droplet volume without adverse impacts on cell growth. Comparing the effects of harmful single-fatty-acid treatments and the well-tolerated fatty acid mixes on the cellular proteome, we were able to differentiate between fatty-acid-specific cellular responses and likely common lipotoxic denominators.

Perspectives in liver redox imbalance: Toxicological and pharmacological aspects underlying iron overloading, nonalcoholic fatty liver disease, and thyroid hormone action

Oxidative stress is an imbalance between oxidants and antioxidants in favor of the oxidants, leading to a disruption of redox signaling and control, and/or molecular damage altering cellular functions. This redox imbalance may trigger different responses depending on the antioxidant potential of a given cell, the level of reactive oxygen/nitrogen species (ROS/RNS) attained and the time of exposure, with protective effects being induced at low ROS/RNS levels in acute or short-term conditions, and harmful effects after high ROS/RNS exposure in prolonged situations. Relevant conditions underlying liver redox imbalance include iron overload associated with ROS production via Fenton chemistry and the magnitude of the iron labile pool achieved, with low iron exposure inducing protective effects related to nuclear factor-κB, signal transducer and activation of transcription 3, and nuclear factor erythroid-related factor 2 (Nrf2) activation and upregulation of ferritin, hepcidin, acute-phase response and antioxidant components, whereas high iron exposure causes drastic oxidation of biomolecules, mitochondrial dysfunction, and cell death due to necrosis, apoptosis and/or ferroptosis. Redox imbalance in nonalcoholic fatty liver disease (NAFLD) is related to polyunsaturated fatty acid depletion, lipogenic factor sterol regulatory element-binding protein-1c upregulation, fatty acid oxidation-dependent peroxisome proliferator-activated receptor-α downregulation, low antioxidant factor Nrf2 and insulin resistance, a phenomenon that is exacerbated in nonalcoholic steatohepatitis triggering an inflammatory response. Thyroid hormone (T₃ ) administration determines liver preconditioning against ischemia-reperfusion injury due to the redox activation of several transcription factors, AMP-activated protein kinase, unfolded protein response and autophagy. High grade liver redox imbalance occurring in severe iron overload is adequately handled by iron chelation, however, that underlying NAFLD/NASH is currently under study in several Phase II and Phase III trials.

Inflammatory Cytokines, Adipocytokines, and Th17/Treg Balance in Patients with Nonalcoholic Fatty Liver Disease following Administration of Dahuang Zhechong Pills

Objectives. The occurrence and development of nonalcoholic fatty liver disease (NAFLD) is related to lipid peroxidation, imbalance of inflammatory response factors, and immune function disorder. This study was conducted with the purpose of investigating the expression levels of inflammatory cytokines and adipocytokines and Th17/Treg balance in NAFLD patients treated with Dahuang Zhechong pills (DHZCPs). Methods. The study recruited 100 NAFLD patients who were then arranged into the test group and control group. Patients in the test group were treated with DHZCPs, while patients in the control group were untreated. Peripheral TH17 and Treg cells were detected by flow cytometry, and peripheral IL-17, IL-10, hs-CRP, and TNF-α expression levels were determined by enzyme-linked immunosorbent assay (ELISA) methods. The concentrations of ghrelin, leptin, and adiponectin were quantitatively examined. Results. The levels of TC, TG, ALT, and AST were declined but the level of HDL-C was increased in NAFLD patients treated with DHZCPs compared with untreated patients ( $P<0.05$ ). The ratio of Th17/Treg in NAFLD patients treated with DHZCPs was (1.52 ± 0.21), which was significantly lower than (2.39 ± 0.45) of untreated patients ( $P<0.05$ ). The levels of IL-17, hs-CRP, and TNF-α were lower, but the level of IL-10 was higher in NAFLD patients treated with DHZCPs than that in untreated patients ( $P<0.05$ ). The expression levels of ghrelin and adiponectin in NAFLD patients treated with DHZCPs were evidently higher than those in untreated patients ( $P<0.01$ ), and the expression level of leptin in NAFLD patients treated with DHZCPs was evidently lower than that in untreated patients ( $P<0.01$ ). Conclusions. Administration of DHZCPs regulates the immune function of NAFLD patients by keeping Th17/Treg balance and affecting the levels of inflammatory cytokines and adipocytokines.

Current Perspectives on Nonalcoholic Fatty Liver Disease in Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is one of the most common reproductive, endocrine, and metabolic disorders in premenopausal women. Clinically, PCOS is mainly caused by androgen excess and ovarian dysfunction, manifested by anovulatory menstrual cycles, infertility, and hirsutism. In addition, PCOS increases the risk of insulin resistance, obesity, cardiovascular disease, anxiety and depression, dyslipidemia, and endometrial cancer. Nonalcoholic fatty liver disease (NAFLD) is defined as ≥5% fat accumulation in the liver in the absence of remaining secondary causes and has become one of the most common chronic liver diseases worldwide. The prevalence of NAFLD is significantly higher and more severe in women with PCOS, and its pathogenesis can be associated with various risk factors such as hyperandrogenemia, insulin resistance, obesity, chronic low-grade inflammation, and genetic factors. Although there is no definitive solution for the management of NAFLD in PCOS, some progress has been made. Lifestyle modification should be the basis of management, and drugs to improve metabolism, such as insulin sensitizers and glucagon-like peptide-1 agonists, may show better efficacy. Bariatric surgery may also be a treatment of NAFLD in obese women with PCOS. This paper reviews three aspects of prevalence, risk factors, and management, in order to better understand the current state of research on NAFLD in PCOS, to explore the pathogenesis of NAFLD in PCOS, and to encourage further research on the application of drugs in this field.

Metabolic Associated Fatty Liver Disease in Children-From Atomistic to Holistic

Non-alcoholic fatty liver disease has become the most common chronic liver disease in children due to the alarmingly increasing incidence of pediatric obesity. It is well-documented that MAFLD prevalence is directly related to an incremental increase in BMI. The multiple hits theory was designed for providing insights regarding the pathogenesis of steatohepatitis and fibrosis in MAFLD. Recent evidence suggested that the microbiome is a crucial contributor in the pathogenesis of MAFLD. Aside from obesity, the most common risk factors for pediatric MAFLD include male gender, low-birth weight, family history of obesity, MAFLD, insulin resistance, type 2 diabetes mellitus, obstructive sleep apnea, and polycystic ovarium syndrome. Usually, pediatric patients with MAFLD have nonspecific symptoms consisting of fatigue, malaise, or diffuse abdominal pain. A wide spectrum of biomarkers was proposed for the diagnosis of MAFLD and NASH, as well as for quantifying the degree of fibrosis, but liver biopsy remains the key diagnostic and staging tool. Nevertheless, elastography-based methods present promising results in this age group as potential non-invasive replacers for liver biopsy. Despite the lack of current guidelines regarding MAFLD treatment in children, lifestyle intervention was proven to be crucial in the management of these patients.

The Role of Vitamin Deficiency in Liver Disease: To Supplement or Not Supplement?

Over the past few years, growing interest has been shown for the impact of dietary requirements and nutritional factors on chronic diseases. As a result, nutritional programs have been reinforced by public health policies. The precise role of micronutrients in chronic liver disease is currently receiving particular attention since abnormalities in vitamin levels are often detected. At present, treatment programs are focused on correcting vitamin deficiencies, which are frequently correlated to higher rates of comorbidities with poor outcomes. The literature reviewed here indicates that liver diseases are often related to vitamin disorders, due to both liver impairment and abnormal intake. More specific knowledge about the role of vitamins in liver disease is currently emerging from various results and recent evidence. The most significant benefits in this area may be observed when improved vitamin intake is combined with a pharmacological treatment that may also affect the progression of the liver disease, especially in the case of liver tumors. However, further studies are needed.

Liver Fibrosis and MAFLD: From Molecular Aspects to Novel Pharmacological Strategies

Metabolic-associated fatty liver disease (MAFLD) is a new disease definition, and this nomenclature MAFLD was proposed to renovate its former name, non-alcoholic fatty liver disease (NAFLD). MAFLD/NAFLD have shared and predominate causes from nutrition overload to persistent liver damage and eventually lead to the development of liver fibrosis and cirrhosis. Unfortunately, there is an absence of effective treatments to reverse MAFLD/NAFLD-associated fibrosis. Due to the significant burden of MAFLD/NAFLD and its complications, there are active investigations on the development of novel targets and pharmacotherapeutics for treating this disease. In this review, we cover recent discoveries in new targets and molecules for antifibrotic treatment, which target pathways intertwined with the fibrogenesis process, including lipid metabolism, inflammation, cell apoptosis, oxidative stress, and extracellular matrix formation. Although marked advances have been made in the development of antifibrotic therapeutics, none of the treatments have achieved the endpoints evaluated by liver biopsy or without significant side effects in a large-scale trial. In addition to the discovery of new druggable targets and pharmacotherapeutics, personalized medication, and combinatorial therapies targeting multiple profibrotic pathways could be promising in achieving successful antifibrotic interventions in patients with MAFLD/NAFLD.

The Role of Vitamins in Non-Alcoholic Fatty Liver Disease: A Systematic Review

Non-Alcoholic Fatty Liver Disease (NAFLD) emerged as the most prevalent liver disorder contributing significantly to disease burden worldwide. It manifests as a broad spectrum of hepatic damage with varying severity ranging from less serious steatosis to a more severe Non-Alcoholic Steatohepatitis (NASH), with or without fibrosis, cirrhosis, and hepatocellular carcinoma. Vitamins, on the other hand, are micronutrients that are vital for healthy well-being. Some studies have linked liver diseases with hypovitaminosis; however, there are still some gaps about the basis of their correlation. Hence, this systematic review aims to discuss the role of vitamins in the pathogenesis of NAFLD and explore their hepatoprotective potential that may benefit clinicians in managing this condition.

This systematic review searched for studies indexed in the PubMed, PubMed Central, Medline, Google Scholar, and ScienceDirect databases. Inclusion and exclusion criteria were applied, duplicates were removed, and meticulous screening of articles was done systematically. Out of 729 unique studies generated using the search strategy, 17 were finally included after thorough review and quality appraisal. 

NAFLD is not simply an outcome of insulin resistance and metabolic derangements; instead, it is a disease with complex underlying pathogenesis. Moreover, vitamin deficiency has been associated with NAFLD development and increased susceptibility to more severe liver damage. Derangement in vitamins correlates to the lipotoxic hepatic environment, altered immune system, unwarranted inflammation, oxidative stress, gene mutations, epigenetic modification, and gut dysbiosis seen in NAFLD. As they influence several pathophysiologic processes in the liver, vitamins A, B3, B6, B9, B12, C, D, and E are promising potential options that can impact NAFLD management. However, more well-designed studies conducted in the human population are still necessary to establish their efficacy and safety as therapeutic agents.

Role of vitamins in the metabolic syndrome and cardiovascular disease

The prevalence of metabolic syndrome and cardiovascular disease has increased and continues to be the leading cause of mortality worldwide. The etiology of these diseases includes a complex phenotype derived from interactions between genetic, environmental, and nutritional factors. In this regard, it is common to observe vitamin deficiencies in the general population and even more in patients with cardiometabolic diseases due to different factors. Vitamins are essential micronutrients for cellular metabolism and their deficiencies result in diseases. In addition to its role in nutritional functions, increasingly, vitamins are being recognized as modulators of genetics expression and signals transduction, when consumed at pharmacological concentrations. Numerous randomized preclinical and clinical trials have evaluated the use of vitamin supplementation in the prevention and treatment of metabolic syndrome and cardiovascular disease. However, it is controversy regarding its efficacy in the treatment and prevention of these diseases. In this review, we investigated chemical basics, physiological effect and recommended daily intake, problems with deficiency and overdose, preclinical and clinical studies, and mechanisms of action of vitamin supplementation in the treatment and prevention of metabolic syndrome and cardiovascular disease.

Associations of Dietary Lipid-Soluble Micronutrients with Hepatic Steatosis among Adults in the United States

Lipid-soluble micronutrients may be beneficial to non-alcoholic fatty liver disease due to their important roles in metabolism and maintaining tissue functions. Utilizing 2017-2018 National Health and Nutrition Examination Survey, this study examined the potential overall and race/ethnicity-specific (black, Hispanic and white) associations of dietary lipid-soluble micronutrients (α-tocopherol, retinol, vitamin D, β-carotene and total carotenoids) with hepatic steatosis. The analysis included 4376 adults (1037 blacks, 981 Hispanics, 1549 whites) aged ≥20 years who completed the transient elastography examination with dietary data available. Odds ratios (OR) and 95% confidence intervals (95%CI) were estimated using logistic regressions. The age-adjusted prevalence of steatosis was 20.9% for blacks, 34.0% for Hispanics and 28.7% for whites. Overall, dietary α-tocopherol was inversely associated with steatosis (highest vs. lowest quartile: OR = 0.51, 95%CI = 0.35-0.74, P_trend = 0.0003). The associations remained significant among blacks (highest vs. lowest tertile: OR = 0.45, 95%CI = 0.26-0.77, P_trend = 0.002) and whites (highest vs. lowest tertile: OR = 0.56, 95%CI = 0.33-0.94, P_trend = 0.02). Higher α-tocopherol intake was associated with lower odds of steatosis among all (P_trend = 0.016) and black participants (P_trend = 0.003) classified as never/rare/occasional alcohol drinkers. There was a trend suggesting higher β-carotene intake with lower odds of steatosis (P_trend = 0.01). Our results suggest potential protective effects of dietary vitamin E as α-tocopherol on steatosis particularly among blacks.

COVID-19 infection and liver injury: Clinical features, biomarkers, potential mechanisms, treatment, and management challenges

It is hypothesized that liver impairment caused by coronavirus disease 2019 (COVID-19) infection might play a central role in severe clinical presentations. Liver injury is closely associated with severe disease and, even with antiviral drugs, have a poor prognosis in COVID-19 patients. In addition to the common hepatobiliary disorders caused by COVID-19, patients with pre-existing liver diseases demand special considerations during the current pandemic. Thus, it is vital that upon clinical presentation, patients with concurrent pre-existing liver disease associated with metabolic dysfunction and COVID-19 be managed properly to prevent liver failure. Careful monitoring and early detection of liver damage through biomarkers after hospitalization for COVID-19 is underscored in all cases, particularly in those with pre-existing metabolic liver injury. The purpose of this study was to determine most recent evidence regarding causality, potential risk factors, and challenges, therapeutic options, and management of COVID-19 infection in vulnerable patients with pre-existing liver injury. This review aims to highlight the current frontier of COVID-19 infection and liver injury and the direction of liver injury in these patients.

Effect of Microbiome on Non-Alcoholic Fatty Liver Disease and the Role of Probiotics, Prebiotics, and Biogenics

Non-alcoholic fatty liver disease (NAFLD) is a leading cause of liver cirrhosis and hepatocellular carcinoma. NAFLD is associated with metabolic disorders such as obesity, insulin resistance, dyslipidemia, steatohepatitis, and liver fibrosis. Liver-resident (Kupffer cells) and recruited macrophages contribute to low-grade chronic inflammation in various tissues by modulating macrophage polarization, which is implicated in the pathogenesis of metabolic diseases. Abnormalities in the intestinal environment, such as the gut microbiota, metabolites, and immune system, are also involved in the pathogenesis and development of NAFLD. Hepatic macrophage activation is induced by the permeation of antigens, endotoxins, and other proinflammatory substances into the bloodstream as a result of increased intestinal permeability. Therefore, it is important to understand the role of the gut–liver axis in influencing macrophage activity, which is central to the pathogenesis of NAFLD and nonalcoholic steatohepatitis (NASH). Not only probiotics but also biogenics (heat-killed lactic acid bacteria) are effective in ameliorating the progression of NASH. Here we review the effect of hepatic macrophages/Kupffer cells, other immune cells, intestinal permeability, and immunity on NAFLD and NASH and the impact of probiotics, prebiotics, and biogenesis on those diseases.

Nutritional Considerations when Dealing with an Underweight Adult or Senior Horse

Weight loss occurs when the supply of energy is insufficient to meet the energy needs of an individual. The energy supply may be reduced by inadequate provision of feed, inadequate consumption, reduced digestion and absorption, or disruption in metabolic processing. Increased energy expenditure occurs with exercise and during cold temperatures, pregnancy, and lactation. Underlying clinical disease, particularly chronic inflammation, neoplasia, and protein-losing conditions, can cause weight loss or exacerbate existing weight loss. A methodical approach to weight-loss investigation and treatment is necessary, because of the often multifactorial nature of this condition.

An Update on Efficacy and Safety of Emerging Hepatic Antifibrotic Agents

Liver fibrosis represents a response to chronic liver injury. Metabolic dysfunction-associated fatty liver disease and metabolic dysfunction-associated steatohepatitis are the most common chronic liver diseases, both with increasing incidence. Therefore, there is a great impetus for development of agents targeting these conditions. Accumulating data on possible treatment options for liver fibrosis are emerging in the literature. However, despite extensive research and much effort in the field, approved agents for liver fibrosis are still lacking. In this critical review, we have summarized the main data about specific treatment options for liver fibrosis gained from ongoing clinical trials, with an emphasis on efficacy and safety of these agents.

An Update on Efficacy and Safety of Emerging Hepatic Antifibrotic Agents

Liver fibrosis represents a response to chronic liver injury. Metabolic dysfunction-associated fatty liver disease and metabolic dysfunction-associated steatohepatitis are the most common chronic liver diseases, both with increasing incidence. Therefore, there is a great impetus for development of agents targeting these conditions. Accumulating data on possible treatment options for liver fibrosis are emerging in the literature. However, despite extensive research and much effort in the field, approved agents for liver fibrosis are still lacking. In this critical review, we have summarized the main data about specific treatment options for liver fibrosis gained from ongoing clinical trials, with an emphasis on efficacy and safety of these agents.

Oxidative Stress in Non-alcoholic Fatty Liver Disease. An Updated Mini Review

Non-alcoholic fatty liver disease (NAFLD) is a challenging disease caused by multiple factors, which may partly explain why it remains still orphan of an adequate therapeutic strategy. Herein we focus on the interplay between oxidative stress (OS) and the other causal pathogenetic factors. Different reactive oxygen species (ROS) generators contribute to NAFLD inflammatory and fibrotic progression, which is quite strictly linked to the lipotoxic liver injury from fatty acids and/or a wide variety of their biologically active metabolites in the context of either a two-hit or a (more recent) multiple parallel hits theory. An antioxidant defense system is usually able to protect hepatic cells from damaging effects caused by ROS, including those produced into the gastrointestinal tract, i.e., by-products generated by usual cellular metabolic processes, normal or dysbiotic microbiota, and/or diet through an enhanced gut–liver axis. Oxidative stress originating from the imbalance between ROS generation and antioxidant defenses is under the influence of individual genetic and epigenetic factors as well. Healthy diet and physical activity have been shown to be effective on NAFLD also with antioxidant mechanisms, but compliance to these lifestyles is very low. Among several considered antioxidants, vitamin E has been particularly studied; however, data are still contradictory. Some studies with natural polyphenols proposed for NAFLD prevention and treatment are encouraging. Probiotics, prebiotics, diet, or fecal microbiota transplantation represent new therapeutic approaches targeting the gut microbiota dysbiosis. In the near future, precision medicine taking into consideration genetic or environmental epigenetic risk factors will likely assist in further selecting the treatment that could work best for a specific patient.