Immunity as Cornerstone of Non-Alcoholic Fatty Liver Disease: The Contribution of Oxidative Stress in the Disease Progression

FLAME: Training and Validating a Newly Conceived Model Incorporating Alpha-Glutathione-S-Transferase Serum Levels for Predicting Advanced Hepatic Fibrosis and Acute Cardiovascular Events in Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Alpha-Glutathione-S-transferase (alphaGST) is a liver enzyme whose serum levels increase with the worsening of fibrosis in alcoholic and viral chronic hepatitis. Its usefulness in Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) remains unexplored. From January 2016 to December 2017, 200 patients with MASLD and 30 controls were enrolled. AlphaGST serum levels were measured. Variables related to advanced fibrosis (AF) were selected via Principal Component Analysis (PCA), and the best cut-off (BCO) was estimated using ROC analysis. Liver stiffness measurement (LSM), NAFLD fibrosis (NFS), Fibrosis-4 (FIB-4), and BMI-AST/ALT Ratio-Diabetes (BARD) scores were determined. The first acute cardiovascular events (ACE) in ACE-naïve subjects were recorded over five years. A validation cohort of 60 MASLD patients was enrolled from January 2018 to May 2019 and followed for five years. AlphaGST levels increased with fibrosis stage (p < 0.0001) in both cohorts, showing high accuracy in predicting AF (TrC: AUC 0.89, VlC: AUC 0.89). PCA-selected variables were HbA1c, HDL, and alphaGST, forming the "FLAME" model. FLAME showed superior predictive performance for AF and ACEs compared to other models and scores. FLAME represents a novel tool that accurately predicts AF and ACEs in MASLD.

The gender and age perspectives of allostatic load

The role of chronic stress in the development of chronic diseases, especially multimorbidity, through the pathways of increasing allostatic load, and finally, allostatic overload (the state when a compensatory mechanism is likely to fail) is being emphasized. However, allostatic load is a dynamic measure that changes depending on sex, gender, age, level and type of stress, experience of a stressful situation, and coping behaviors. Many other factors such as race, ethnicity, working environment, lifestyle, and circadian rhythm of sleep are also important. The aim of this paper was to synthesize the available information on allostatic load differences, especially those connected to sex/gender and age, and to provide a model for the future study of allostatic load, with a focus on these differences. By carefully studying allostatic load factors, we realized that many studies do not take this allostatic load difference into account in the analysis methods. In this paper, we also support the idea of further research to develop new allostatic load analysis strategies that will include all knowledge about sex/gender differences and that will, in more detail, explain numerous changeable social and educational factors that are currently accepted as biological ones. Furthermore, specific allostatic load biomarkers are expressed differently in different age groups, indicating that the discrepancies cannot be attributed solely to sex/gender disparities. This kind of approach can be valuable, not only for better explaining the differences in the frequency and age of onset of chronic diseases and multimorbidity, but also for the potential planning and development of preventive actions based on the aforementioned sex/gender and age disaparities, in order to prevent the most frequent diseases and to establish specific biomarker cut-off values for each sex/gender and age group.

Hepatoprotective potential of coconut inflorescence sap against paracetamol induced toxicity in hep G2 cell lines

Coconut Inflorescence Sap (CIS) is the sweet, oyster-white colored, non-fermented juice obtained from the immature inflorescence of the Coconut tree. Acetaminophen (N-acetyl-p-aminophenol, or paracetamol) is one of the most frequently used drugs worldwide as an antipyretic or analgesic. HepG2 cell lines were used as an experimental model for studying in vitro hepatotoxicity induced by Paracetamol. The present study aims to identify biologically active compounds of CIS using LCMS analysis and to elucidate the ameliorative potential of CIS in alleviating paracetamol-induced hepatotoxicity. LC-MS analysis revealed the presence of 17 bioactive compounds. HepG2 cells were pretreated with Paracetamol (20 mM) for inducing toxicity, and Silymarin at a concentration of 50 μg/ml was used as a standard drug. The morphological analysis and MTT assay showed effective recovery from toxicity in cells treated with CIS in a dose-dependent manner. CIS at 25 μg/ml potentially showed the highest percentage of inhibitory activity against the toxicity induced by paracetamol. The treatment with paracetamol significantly increased the indicators of liver toxicity - LDH, SGOT, SGPT, and Glut.S Transferase in the media.CIS administration also increased the total protein levels, SOD, and Catalase activity. The morphological analysis, MTT assay, cytocompatibility studies, determination of enzymatic activities, etc., confirms the significant hepatoprotective efficacy of CIS.

In Vitro Nonalcoholic Fatty Liver Disease Model Elucidating the Effect of Immune Environment on Disease Progression and Alleviation

Nonalcoholic fatty liver disease (NAFLD), which is a major cause of chronic liver disease, is characterized by fat accumulation in the liver. Existing models struggle to assess medication effects on liver function in the context of NAFLD's unique inflammatory environment. We address this by developing a 3D in vitro NAFLD model using HepG2 and THP-1 cells (mimicking liver and Kupffer cells) cocultured using transwell and hydrogel system. This mimics liver architecture and allows for manipulation of the immune environment. We demonstrate that the model recapitulates key NAFLD features: steatosis (induced by fatty acids), oxidative stress, inflammation, and impaired liver function embodying the interrelationship between NAFLD and the surrounding immune environment. This versatile model offers a valuable tool for preclinical NAFLD research by incorporating a disease-relevant immune environment.

The influence of acute lifestyle changes on NAFLD evolution in a multicentre cohort: a matter of body composition

BACKGROUND

Unhealthy lifestyles represent a key element fueling Non-alcoholic fatty liver disease (NAFLD) onset and worsening. We aimed to evaluate the effects of forced acute lifestyle changes on NAFLD evolution.

METHODS

187 NAFLD patients were followed two years pre- and two years during the lockdown social restrictions in three Italian medical centers. For each patient, biochemical, clinical, non-invasive liver fibrosis, nutritional, and body composition data were collected.

RESULTS

An increase in fats and carbohydrate intake associated with impaired weekly physical activity during the lockdown was demonstrated as well as an increase in body mass index and waist-hip-ratio (p < 0.0001 for all). Total cholesterol, low-density lipoprotein, high-density lipoprotein, triglycerides, glucose, insulin, homeostatic model assessment for insulin resistance, and transaminases worsened during the lockdown (glucose: p = 0.0007; p < 0.0001 for the others). Moreover, NAFLD fibrosis score, liver stiffness, and controlled attenuation parameter were also impaired during the same period (p < 0.0001 for all). The bioelectrical impedance analysis (BIA) evidenced an increase of fat mass (FM), and a reduction of free fat mass (FFM) and body cell mass (BCM) (p < 0.0001 for all). The lockdown overall hepatocellular carcinoma (HCC) and Milan-out HCC occurrence revealed Hazard Ratio (HR): 2.398, 95% Confidence Interval (CI):1.16-5, p = 0.02, and HR:5.931, CI:2-17.6, p = 0.008 respectively. A liver disease stage and comorbidities independent association between both the assessed outcomes and body composition analysis in terms of mean values and variation (T1-T2 Δ) was demonstrated.

CONCLUSIONS

The acute lifestyle changes impacted NAFLD evolution via body composition modifications negatively influencing the HCC occurrence.

Monocyte bioenergetics: An immunometabolic perspective in metabolic dysfunction-associated steatohepatitis

Monocytes (Mos) are crucial in the evolution of metabolic dysfunction-associated steatotic liver disease (MASLD) to metabolic dysfunction-associated steatohepatitis (MASH), and immunometabolism studies have recently suggested targeting leukocyte bioenergetics in inflammatory diseases. Here, we reveal a peculiar bioenergetic phenotype in circulating Mos of patients with MASH, characterized by high levels of glycolysis and mitochondrial (mt) respiration. The enhancement of mt respiratory chain activity, especially complex II (succinate dehydrogenase [SDH]), is unbalanced toward the production of reactive oxygen species (ROS) and is sustained at the transcriptional level with the involvement of the AMPK-mTOR-PGC-1α axis. The modulation of mt activity with dimethyl malonate (DMM), an SDH inhibitor, restores the metabolic profile and almost abrogates cytokine production. Analysis of a public single-cell RNA sequencing (scRNA-seq) dataset confirms that in murine models of MASH, liver Mo-derived macrophages exhibit an upregulation of mt and glycolytic energy pathways. Accordingly, the DMM injection in MASH mice contrasts Mo infiltration and macrophagic enrichment, suggesting immunometabolism as a potential target in MASH.

Contributing roles of mitochondrial dysfunction and hepatocyte apoptosis in liver diseases through oxidative stress, post-translational modifications, inflammation, and intestinal barrier dysfunction

This review provides an update on recent findings from basic, translational, and clinical studies on the molecular mechanisms of mitochondrial dysfunction and apoptosis of hepatocytes in multiple liver diseases, including but not limited to alcohol-associated liver disease (ALD), metabolic dysfunction-associated steatotic liver disease (MASLD), and drug-induced liver injury (DILI). While the ethanol-inducible cytochrome P450-2E1 (CYP2E1) is mainly responsible for oxidizing binge alcohol via the microsomal ethanol oxidizing system, it is also responsible for metabolizing many xenobiotics, including pollutants, chemicals, drugs, and specific diets abundant in n-6 fatty acids, into toxic metabolites in many organs, including the liver, causing pathological insults through organelles such as mitochondria and endoplasmic reticula. Oxidative imbalances (oxidative stress) in mitochondria promote the covalent modifications of lipids, proteins, and nucleic acids through enzymatic and non-enzymatic mechanisms. Excessive changes stimulate various post-translational modifications (PTMs) of mitochondrial proteins, transcription factors, and histones. Increased PTMs of mitochondrial proteins inactivate many enzymes involved in the reduction of oxidative species, fatty acid metabolism, and mitophagy pathways, leading to mitochondrial dysfunction, energy depletion, and apoptosis. Unique from other organelles, mitochondria control many signaling cascades involved in bioenergetics (fat metabolism), inflammation, and apoptosis/necrosis of hepatocytes. When mitochondrial homeostasis is shifted, these pathways become altered or shut down, likely contributing to the death of hepatocytes with activation of inflammation and hepatic stellate cells, causing liver fibrosis and cirrhosis. This review will encapsulate how mitochondrial dysfunction contributes to hepatocyte apoptosis in several types of liver diseases in order to provide recommendations for targeted therapeutics.

Association between nonalcoholic fatty liver disease and increased glucose-to-albumin ratio in adults without diabetes

Background

Nonalcoholic fatty liver disease (NAFLD) affects approximately 30% of individuals globally. Both serum glucose and albumin were demonstrated to be potential markers for the development of NAFLD. We hypothesized that the risk of NAFLD may be proportional to the glucose-to-albumin ratio (GAR).

Methods

Based on information from the National Health and Nutrition Examination Survey (NHANES) 1999-2018, it was determined that GAR was associated with an increased risk of NAFLD and liver fibrosis utilizing weighted multivariable logistic regression. Participants with a fatty liver index (FLI) over 60 were identified with NAFLD, and those with an NAFLD fibrosis score (NFS) >0.676 with evidence of NAFLD were labeled with advanced hepatic fibrosis (AHF). The liver biopsy was utilized to verify the relationship between GAR and FLD in our center cohort. Mendelian randomization analysis investigated the genetic relationship between GAR and NAFLD.

Results

Of 15,534 eligible participants, 36.4% of participants were identified as NAFLD without AHF. GAR was positively correlated with the probability of NAFLD following full adjustment for possible variables (OR = 1.53, 95% CI: 1.39-1.67). It was confirmed that patients with NAFLD and AHF had an inferior prognosis. The relationship between GAR and NFS was favorable (R = 0.46, P< 0.0001), and NAFLD patients with a higher GAR tended to develop poor survival. In our center cohort, the association between GAR and NAFLD was verified.

Conclusion

Among participants without diabetes, greater GAR was linked to higher risks of NAFLD. In addition, NAFLD patients with higher GAR tended to develop liver fibrosis and adverse outcomes.

Melatonin Prevents Alcohol- and Metabolic Dysfunction- Associated Steatotic Liver Disease by Mitigating Gut Dysbiosis, Intestinal Barrier Dysfunction, and Endotoxemia

Melatonin (MT) has often been used to support good sleep quality, especially during the COVID-19 pandemic, as many have suffered from stress-related disrupted sleep patterns. It is less known that MT is an antioxidant, anti-inflammatory compound, and modulator of gut barrier dysfunction, which plays a significant role in many disease states. Furthermore, MT is produced at 400-500 times greater concentrations in intestinal enterochromaffin cells, supporting the role of MT in maintaining the functions of the intestines and gut-organ axes. Given this information, the focus of this article is to review the functions of MT and the molecular mechanisms by which it prevents alcohol-associated liver disease (ALD) and metabolic dysfunction-associated steatotic liver disease (MASLD), including its metabolism and interactions with mitochondria to exert its antioxidant and anti-inflammatory activities in the gut-liver axis. We detail various mechanisms by which MT acts as an antioxidant, anti-inflammatory compound, and modulator of intestinal barrier function to prevent the progression of ALD and MASLD via the gut-liver axis, with a focus on how these conditions are modeled in animal studies. Using the mechanisms of MT prevention and animal studies described, we suggest behavioral modifications and several exogenous sources of MT, including food and supplements. Further clinical research should be performed to develop the field of MT in preventing the progression of liver diseases via the gut-liver axis, so we mention a few considerations regarding MT supplementation in the context of clinical trials in order to advance this field of research.

Dihydroartemisinin ameliorates the liver steatosis in metabolic associated fatty liver disease mice by attenuating the inflammation and oxidative stress and promoting autophagy

PURPOSE

To explore the effect and potential mechanism of dihydroartemisinin (DHA) on metabolism-related fatty liver disease.

METHODS

A metabolic associated fatty liver disease (MAFLD) mice model was induced with continuous supplies of high-fat diet. DHA was intraperitoneally injected into mice. The weight of mice was monitored. The concentrations of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) in serum were detected by an automatic biochemical analyzer. The liver tissues were stained by hematoxylin and eosin and oil red O. The level of inflammation, oxidative stress, and autophagy was assessed by reverse transcription polymerase chain reaction, biochemical examination, Western blot and transmission electron microscope assays.

RESULTS

DHA treatment reduced theMAFLD-enhanced the level of weight gain, the concentrations of TC, TG, LDL and malonaldehyde, while increasedthe MAFLD-decreased the concentrations of HDL and superoxide dismutase. DHA ameliorated the MAFLD-aggravated pathological changes and the number of lipid droplets. Low dose of DHA declined the MAFLD-induced the enhancement of the expression of inflammatory factor. DHA treatment increased the MAFLD-enhanced the level of autophagy related protein, while decreased the MAFLD-reduced the protein level of p62. The increased level of autophagy was confirmed by transmission electron microscope.

CONCLUSIONS

DHA can improve liver steatosis in MAFLD mice by inhibiting inflammation and oxidative stress and promoting autophagy.

The clinical value of the monocyte to high-density lipoprotein cholesterol ratio and alkaline phosphatase-to-platelet ratio in primary biliary cholangitis

This study aimed to evaluate the clinical value of the monocyte to high-density lipoprotein cholesterol ratio (MHR) and alkaline phosphatase-to-platelet ratio (APPR) in the diagnosis and prognosis of primary biliary cholangitis (PBC). Clinical and laboratory data were retrospectively collected and analyzed from 92 PBC patients, 92 patients with autoimmune hepatitis (AIH), 120 patients with chronic hepatitis B (CHB) and 124 healthy controls (HCs). We compared the levels of MHR and APPR among the groups with PBC, AIH, CHB and HCs, and analyzed the correlations between MHR and APPR with laboratory indices including aspartate aminotransferase platelet ratio index, fibrosis index based on 4 factors, and Mayo score in PBC. Receiver operating characteristic curves were used to analyze the diagnostic performance of MHR and APPR for PBC, AIH, and CHB, respectively. MHR and APPR were significantly increased in PBC group than that in AIH, CHB and HCs groups (each P < .05). MHR and APPR were significantly higher in Child class B|C than that in class A in PBC patients. (P < .01, P < .05, respectively). MHR and APPR were positively related to the Mayo score [R = 0.508 (P < .001), R = 0.295 (P = .008), respectively]. The area under the receiver operating characteristic curves of MHR and APPR in diagnosing PBC were 0.764 (95% confidence interval [CI]: 0.699-0.821, P < .001) and 0.952 (95% CI: 0.915-0.977, P < .001), respectively, and the area under the curve of the combination of both was 0.974 (95% CI: 0.941-0.991, P < .001). MHR and APPR may prove to be useful prognostic biomarkers for PBC, and the combination of MHR and APPR have some clinical diagnostic value of PBC.

The use of bicarbonate-sulphate-calcium-magnesium and sodium-low drinkable water improves functional gastrointestinal symptoms in patients with non-alcoholic fatty liver disease: A prospective study

BACKGROUND & AIMS

Non-alcoholic fatty liver disease is increasingly gaining epidemiological ground in liver diseases. Among the proposed non-pharmacologic interventions, dietary interventions have been widely used. Several patients suffering from it complain of gastrointestinal symptoms unrelated to organic gastrointestinal tract disease. However, the role of drinking water quality modifications in this regard has not been investigated in depth.

METHODS

Patients with upper or lower functional gastrointestinal symptoms were enrolled and divided into groups based on bright liver ultrasound relief's presence (SP) or absence (NSP). These patients were asked to drink bicarbonate-sulphate-calcium-magnesium and sodium-low drinkable water (Fonte Essenziale ®) for six months. Participants were assessed at baseline (T0), at the end of six months of drinking water intake (T6), and after an additional six months of washout (T12) by questionnaires designed to evaluate lower and upper gastrointestinal symptoms (Leeds dyspepsia score, short form) severity and frequency.

RESULTS

A total of 61 patients were enrolled. In the SP population, the severity of lower gastrointestinal symptoms improved between T0-T6 (Z: -2.437; ES: 0.312) and worsened after the water washout (Z: -2.492; ES: 0.319). The same was for the Leeds score severity sub score in T0-T6 (Z: -2.850; ES: 0.364) and T6-T12 (Z: -2.921; ES: 0.374). These improvements seem unrelated to the severity of liver steatosis at baseline. Furthermore, no safety issues were recorded while taking the water nor during the six-month follow-up afterwards.

CONCLUSION

Regular six-month intake of 400 mL of Fonte Essenziale® water was associated, in the absence of dietary regimen modifications, with an improvement in some qualitative and quantitative features of upper and lower functional gastrointestinal symptoms in both an SP and NSP sample.

Preventive and therapeutic effects of natural products and herbal extracts on nonalcoholic fatty liver disease/nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is a common condition that is prevalent in patients who consume little or no alcohol, and is characterized by excessive fat accumulation in the liver. The disease is becoming increasingly common with the rapid economic development of countries. Long-term accumulation of excess fat can lead to NAFLD, which represents a global health problem with no effective therapeutic approach. NAFLD is a complex, multifaceted pathological process that has been the subject of extensive research over the past few decades. Herbal medicines have gained attention as potential therapeutic agents to prevent and treat NAFLD due to their high efficacy and low risk of side effects. Our overview is based on a PubMed and Web of Science database search as of Dec 22 with the keywords: NAFLD/NASH Natural products and NAFLD/NASH Herbal extract. In this review, we evaluate the use of herbal medicines in the treatment of NAFLD. These natural resources have the potential to inform innovative drug research and the development of treatments for NAFLD in the future.

Innovative Therapeutic Approaches in Non-Alcoholic Fatty Liver Disease: When Knowing Your Patient Is Key

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of disorders ranging from simple steatosis to non-alcoholic steatohepatitis (NASH). Hepatic steatosis may result from the dysfunction of multiple pathways and thus multiple molecular triggers involved in the disease have been described. The development of NASH entails the activation of inflammatory and fibrotic processes. Furthermore, NAFLD is also strongly associated with several extra-hepatic comorbidities, i.e., metabolic syndrome, type 2 diabetes mellitus, obesity, hypertension, cardiovascular disease and chronic kidney disease. Due to the heterogeneity of NAFLD presentations and the multifactorial etiology of the disease, clinical trials for NAFLD treatment are testing a wide range of interventions and drugs, with little success. Here, we propose a narrative review of the different phenotypic characteristics of NAFLD patients, whose disease may be triggered by different agents and driven along different pathophysiological pathways. Thus, correct phenotyping of NAFLD patients and personalized treatment is an innovative therapeutic approach that may lead to better therapeutic outcomes.

Architectural Allostatic Overloading: Exploring a Connection between Architectural Form and Allostatic Overloading

This paper examines, conceptually, the relationship between stress-inducing architectural features and allostatic overload by drawing on literature from neuroimmunology and neuroarchitecture. The studies reviewed from the field of neuroimmunology indicate that chronic or repeated exposure to stress-inducing events may overwhelm the body's regulatory system, resulting in a process termed allostatic overload. While there is evidence from the field of neuroarchitecture that short-term exposure to particular architectural features produce acute stress responses, there is yet to be a study on the relationship between stress-inducing architectural features and allostatic load. This paper considers how to design such a study by reviewing the two primary methods used to measure allostatic overload: biomarkers and clinimetrics. Of particular interest is the observation that the clinical biomarkers used to measure stress in neuroarchitectural studies differ substantially from those used to measure allostatic load. Therefore, the paper concludes that while the observed stress responses to particular architectural forms may indicate allostatic activity, further research is needed to determine whether these stress responses are leading to allostatic overload. Consequently, a discrete longitudinal public health study is advised, one which engages the clinical biomarkers indicative of allostatic activity and incorporates contextual data using a clinimetric approach.

Dietary gluten worsens hepatic steatosis by increasing inflammation and oxidative stress in ApoE-/- mice fed a high-fat diet

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disorder in the world. We have seen that gluten intake exacerbated obesity and atherosclerosis in apolipoprotein E knockout (ApoE-/-) mice. In this study, we investigated the effect of gluten consumption on inflammation and oxidative stress in the liver of mice with NAFLD. Male ApoE-/- mice were fed a gluten-free (GF-HFD) or gluten-containing (G-HFD) high-fat diet for 10 weeks. Blood, liver, and spleen were collected to perform the analyses. The animals of the gluten group had increased hepatic steatosis, followed by increased serum AST and ALT. Gluten intake increased hepatic infiltration of neutrophils, macrophages, and eosinophils, as well as the levels of chemotaxis-related factors CCL2, Cxcl2, and Cxcr3. The production of the TNF, IL-1β, IFNγ, and IL-4 cytokines in the liver was also increased by gluten intake. Furthermore, gluten exacerbated the hepatic lipid peroxidation and nitrotyrosine deposition, which were associated with increased production of ROS and nitric oxide. These effects were related to increased expression of NADPH oxidase and iNOS, as well as decreased activity of superoxide dismutase and catalase enzymes. There was an increased hepatic expression of the NF-κB and AP1 transcription factors, corroborating the worsening effect of gluten on inflammation and oxidative stress. Finally, we found an increased frequency of CD4+FOXP3+ lymphocytes in the spleen and increased gene expression of Foxp3 in the livers of the G-HFD group. In conclusion, dietary gluten aggravates NAFLD, exacerbating hepatic inflammation and oxidative stress in obese ApoE-deficient mice.

Antioxidant and anti-inflammatory agents in chronic liver diseases: Molecular mechanisms and therapy

Chronic liver disease (CLD) is a continuous process that causes a reduction of liver function lasting more than six months. CLD includes alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), chronic viral infection, and autoimmune hepatitis, which can lead to liver fibrosis, cirrhosis, and cancer. Liver inflammation and oxidative stress are commonly associated with the development and progression of CLD. Molecular signaling pathways such as AMP-activated protein kinase (AMPK), C-Jun N-terminal kinase, and peroxisome proliferator-activated receptors (PPARs) are implicated in the pathogenesis of CLD. Therefore, antioxidant and anti-inflammatory agents from natural products are new potent therapies for ALD, NAFLD, and hepatocellular carcinoma (HCC). In this review, we summarize some powerful products that can be potential applied in all the stages of CLD, from ALD/NAFLD to HCC. The selected agents such as β-sitosterol, curcumin, genistein, and silymarin can regulate the activation of several important molecules, including AMPK, Farnesoid X receptor, nuclear factor erythroid 2-related factor-2, PPARs, phosphatidylinositol-3-kinase, and lysyl oxidase-like proteins. In addition, clinical trials are undergoing to evaluate their efficacy and safety.

Single-cell transcriptomics of hepatic stellate cells uncover crucial pathways and key regulators involved in non-alcoholic steatohepatitis

Background

Fibrosis is an important pathological process in the development of non-alcoholic steatohepatitis (NASH), and the activation of hepatic stellate cell (HSC) is a central event in liver fibrosis. However, the transcriptomic change of activated HSCs (aHSCs) and resting HSCs (rHSCs) in NASH patients has not been assessed. This study aimed to identify transcriptomic signature of HSCs during the development of NASH and the underlying key functional pathways.

Methods

NASH-associated transcriptomic change of HSCs was defined by single-cell RNA-sequencing (scRNA-seq) analysis, and those top upregulated genes were identified as NASH-associated transcriptomic signatures. Those functional pathways involved in the NASH-associated transcriptomic change of aHSCs were explored by weighted gene co-expression network analysis (WGCNA) and functional enrichment analyses. Key regulators were explored by upstream regulator analysis and transcription factor enrichment analysis.

Results

scRNA-seq analysis identified numerous differentially expressed genes in both rHSCs and aHSCs between NASH patients and healthy controls. Both scRNA-seq analysis and in-vivo experiments showed the existence of rHSCs (mainly expressing a-SMA) in the normal liver and the increased aHSCs (mainly expressing collagen 1) in the fibrosis liver tissues. NASH-associated transcriptomic signature of rHSC (NASHrHSCsignature) and NASH-associated transcriptomic signature of aHSC (NASHaHSCsignature) were identified. WGCNA revealed the main pathways correlated with the transcriptomic change of aHSCs. Several key upstream regulators and transcription factors for determining the functional change of aHSCs in NASH were identified.

Conclusion

This study developed a useful transcriptomic signature with the potential in assessing fibrosis severity in the development of NASH. This study also identified the main pathways in the activation of HSCs during the development of NASH.

[Innate and adaptive immunity in the context of non-alcoholic fatty liver disease]

Non-alcoholic fatty liver disease (NAFLD) is a growing health problem. Understanding the immunological processes in the liver during the development and progression of fatty liver disease to fatty liver inflammation (NASH), liver cirrhosis or hepatocellular carcinoma (HCC) can be used to better understand the disease, identify clinically relevant subgroups and therapeutic approaches. The interaction between innate and acquired immune systems seems to be of great importance. This review article highlights the various immunological processes in NAFLD leading up to progression to HCC, organized according to the major cell groups of the innate and acquired immune systems.

Cytokines and Hepatocellular Carcinoma: Biomarkers of a Deadly Embrace

Hepatocellular carcinoma (HCC) represents a worldwide health matter with a major care burden, high prevalence, and poor prognosis. Its pathogenesis mainly varies depending on the underlying etiological factors, although it develops from liver cirrhosis in the majority of cases. This review summarizes the role of the most interesting soluble factors as biomarkers for early diagnosis and as recommended targets for treatment in accordance with the new challenges in precision medicine. In the premalignant environment, inflammatory cells release a wide range of cytokines, chemokines, growth factors, prostaglandins, and proangiogenic factors, making the liver environment more suitable for hepatocyte tumor progression that starts from acquired genetic mutations. A complex interaction of pro-inflammatory (IL-6, TNF-α) and anti-inflammatory cytokines (TGF-α and -β), pro-angiogenic molecules (including the Angiopoietins, HGF, PECAM-1, HIF-1α, VEGF), different transcription factors (NF-kB, STAT-3), and their signaling pathways are involved in the development of HCC. Since cytokines are expressed and released during the different stages of HCC progression, their measurement, by different available methods, can provide in-depth information on the identification and management of HCC.

Mesenchymal stem cells-based therapy in liver diseases

Multiple immune cells and their products in the liver together form a complex and unique immune microenvironment, and preclinical models have demonstrated the importance of imbalances in the hepatic immune microenvironment in liver inflammatory diseases and immunocompromised liver diseases. Various immunotherapies have been attempted to modulate the hepatic immune microenvironment for the purpose of treating liver diseases. Mesenchymal stem cells (MSCs) have a comprehensive and plastic immunomodulatory capacity. On the one hand, they have been tried for the treatment of inflammatory liver diseases because of their excellent immunosuppressive capacity; On the other hand, MSCs have immune-enhancing properties in immunocompromised settings and can be modified into cellular carriers for targeted transport of immune enhancers by genetic modification, physical and chemical loading, and thus they are also used in the treatment of immunocompromised liver diseases such as chronic viral infections and hepatocellular carcinoma. In this review, we discuss the immunological basis and recent strategies of MSCs for the treatment of the aforementioned liver diseases. Specifically, we update the immune microenvironment of the liver and summarize the distinct mechanisms of immune microenvironment imbalance in inflammatory diseases and immunocompromised liver diseases, and how MSCs can fully exploit their immunotherapeutic role in liver diseases with both immune imbalance patterns.

Urinary volatile Organic compounds in non-alcoholic fatty liver disease (NAFLD), type two diabetes mellitus (T2DM) and NAFLD-T2DM coexistence

INTRODUCTION

Accumulating evidence have shown a significant correlation between urinary volatile organic compounds (VOCs) profile and the manifestation of several physiological and pathological states, including liver diseases. Previous studies have investigated the urinary metabolic signature as a non-invasive tool for the early discrimination between non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH), which nowadays represents one of the most important challenges in this context, feasible only by carrying out liver biopsy.

OBJECTIVES

The aim of the study was to investigate the differences in the urinary VOCs profiles of non-alcoholic fatty liver disease (NAFLD) patients, diabetes mellitus (T2DM) subjects and NAFLD/T2DM patients.

METHODS

Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was applied to profile the urinary VOCs. Urine samples were analysed both under acid and alkaline conditions, to obtain a range of urinary volatiles with different physicochemical properties.

RESULTS

Urinary VOCs profiles of 13 NAFLD patients, 13 T2DM subjects and 13 NAFLD/T2DM patients were investigated by multivariate and univariate data analysis techniques which allowed to identify 21 volatiles under alkaline conditions able to describe the NAFLD/T2DM group concerning the other two groups.

CONCLUSION

Our results suggest that VOCs signatures can improve the knowledge of the pathological condition where NAFLD coexists with T2DM and discovering new features that are not simply the sum of the two diseases. These preliminary findings may be considered as hypothesis-generating, to be clearly confirmed by larger prospective investigations.

Polysaccharides influence human health via microbiota-dependent and -independent pathways

Polysaccharides are the most diverse molecules and can be extracted from abundant edible materials. Increasing research has been conducted to clarify the structure and composition of polysaccharides obtained from different materials and their effects on human health. Humans can only directly assimilate very limited polysaccharides, most of which are conveyed to the distal gut and fermented by intestinal microbiota. Therefore, the main mechanism underlying the bioactive effects of polysaccharides on human health involves the interaction between polysaccharides and microbiota. Recently, interest in the role of polysaccharides in gut health, obesity, and related disorders has increased due to the wide range of valuable biological activities of polysaccharides. The known roles include mechanisms that are microbiota-dependent and involve microbiota-derived metabolites and mechanisms that are microbiota-independent. In this review, we discuss the role of polysaccharides in gut health and metabolic diseases and the underlying mechanisms. The findings in this review provide information on functional polysaccharides in edible materials and facilitate dietary recommendations for people with health issues. To uncover the effects of polysaccharides on human health, more clinical trials should be conducted to confirm the therapeutic effects on gut and metabolic disease. Greater attention should be directed toward polysaccharide extraction from by-products or metabolites derived from food processing that are unsuitable for direct consumption, rather than extracting them from edible materials. In this review, we advanced the understanding of the structure and composition of polysaccharides, the mutualistic role of gut microbes, the metabolites from microbiota-fermenting polysaccharides, and the subsequent outcomes in human health and disease. The findings provide insight into the proper application of polysaccharides in improving human health.

Immune checkpoint inhibitors in HCC: Cellular, molecular and systemic data

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer related deaths in the world, and for patients with advanced disease there are few therapeutic options available. The complex immunological microenvironment of HCC and the success of immunotherapy in several types of tumours, has raised the prospect of potential benefit for immune based therapies, such as immune checkpoint inhibitors (ICIs), in HCC. This has led to significant breakthrough research, numerous clinical trials and the rapid approval of multiple systemic drugs for HCC by regulatory bodies worldwide. Although some patients responded well to ICIs, many have failed to achieve significant benefit, while others showed unexpected and paradoxical deterioration. The aim of this review is to discuss the pathophysiology of HCC, the tumour microenvironment, key clinical trials evaluating ICIs in HCC, various resistance mechanisms to ICIs, and possible ways to overcome these impediments to improve patient outcomes.

Fine-tuning of regulatory T cells is indispensable for the metabolic steatosis-related hepatocellular carcinoma: A review

The majority of chronic hepatic diseases are caused by nutritional imbalance. These nutritional inequities include excessive intake of alcohol and fat, which causes alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD), respectively. The pathogenesis of hepatic diseases is mainly dependent on oxidative stress, autophagy, DNA damage, and gut microbiota and their metabolites. These factors influence the normal physiology of the liver and impact the hepatic microenvironment. The hepatic microenvironment contains several immune cells and inflammatory cytokines which interact with each other and contribute to the progression of chronic hepatic diseases. Among these immune cells, Foxp3⁺ CD4⁺ regulatory T cells (Tregs) are the crucial subset of CD4⁺ T cells that create an immunosuppressive environment. This review emphasizes the function of Tregs in the pathogenesis of ALD and NAFLD and their role in the progression of NAFLD-associated hepatocellular carcinoma (HCC). Briefly, Tregs establish an immunosuppressive landscape in the liver by interacting with the innate immune cells and gut microbiota and their metabolites. Meanwhile, with the advancement of steatosis, these Tregs inhibit the proliferation, activation and functions of other cytotoxic T cells and support the progression of simple steatosis to HCC. Briefly, it can be suggested that targeting Tregs can act as a favourable prognostic indicator by modulating steatosis and insulin resistance during the pathogenesis of hepatic steatosis and NAFLD-associated HCC.

Just Drink a Glass of Water? Effects of Bicarbonate–Sulfate–Calcium–Magnesium Water on the Gut–Liver Axis

Background and Aim: Fonte Essenziale® water is a bicarbonate–sulfate–calcium–magnesium water, low in sodium, recognized by the Italian health care system in hydropinotherapy and hepatobiliary dyspepsia therapy. We wanted to explore its effects on the gut–liver axis and microbiota in non-alcoholic fatty liver disease patients.

Patients and Methods: We considered enrollment for 70 patients, of which four were excluded. We finally enrolled 55 patients with ultrasound-documented steatosis (SPs+) and 11 patients without it (SPs−). They then drank 400 ml of water for 6 months in the morning on an empty stomach. Routine hematochemical and metabolic parameters, oxidative stress parameters, gastrointestinal hormone levels, and fecal parameters of the gut microbiota were evaluated at three different assessment times, at baseline (T0), after 6 months (T6), and after a further 6 months of water washout (T12). We lost, in follow-up, 4 (T6) and 22 (T12) patients.

Results: Between T0–T6, we observed a significant Futuin A and Selenoprotein A decrease and a GLP-1 and PYY increase in SPs+ and the same for Futuin A and GLP-1 in SPs−. Effects were lost at T12. In SPs+, between T0–T12 and T6–12, a significant reduction in Blautia was observed; between T0–T12, a reduction of Collinsella unc. was observed; and between T0–T12 and T6–12, an increase in Subdoligranulum and Dorea was observed. None of the bacterial strains we analyzed varied significantly in the SPs− population.

Conclusion: These results indicate beneficial effects of water on gastrointestinal hormones and hence on the gut–liver axis in the period in which subjects drank water both in SPs− and in SPs+.

The Role of Insulin Resistance in Fueling NAFLD Pathogenesis: From Molecular Mechanisms to Clinical Implications

Non-alcoholic fatty liver disease (NAFLD) represents a predominant hepatopathy that is rapidly becoming the most common cause of hepatocellular carcinoma worldwide. The close association with metabolic syndrome’s extrahepatic components has suggested the nature of the systemic metabolic-related disorder based on the interplay between genetic, nutritional, and environmental factors, creating a complex network of yet-unclarified pathogenetic mechanisms in which the role of insulin resistance (IR) could be crucial. This review detailed the clinical and pathogenetic evidence involved in the NAFLD–IR relationship, presenting both the classic and more innovative models. In particular, we focused on the reciprocal effects of IR, oxidative stress, and systemic inflammation on insulin-sensitivity disruption in critical regions such as the hepatic and the adipose tissue, while considering the impact of genetics/epigenetics on the regulation of IR mechanisms as well as nutrients on specific insulin-related gene expression (nutrigenetics and nutrigenomics). In addition, we discussed the emerging capability of the gut microbiota to interfere with physiological signaling of the hormonal pathways responsible for maintaining metabolic homeostasis and by inducing an abnormal activation of the immune system. The translation of these novel findings into clinical practice could promote the expansion of accurate diagnostic/prognostic stratification tools and tailored pharmacological approaches.

Very Low Alcohol Consumption Is Associated with Lower Prevalence of Cirrhosis and Hepatocellular Carcinoma in Patients with Non-Alcoholic Fatty Liver Disease

The role of moderate alcohol consumption in the evolution of NAFLD is still debated. The aim of this study is to evaluate the impact of current and lifelong alcohol consumption in patients with NAFLD. From 2015 to 2020, we enrolled 276 consecutive patients fulfilling criteria of NAFLD (alcohol consumption up to 140 g/week for women and 210 g/week for men). According to their current alcohol intake per week, patients were divided in: abstainers, very low consumers (C1: <70 g/week) and moderate consumers (C2). We created a new tool, called LACU (Lifetime Alcohol Consuming Unit) to estimate the alcohol exposure across lifetime: 1 LACU was defined as 7 alcohol units per week for 1 drinking year. Patients were divided into lifelong abstainers and consumers and the latter furtherly divided into quartiles: Q1-Q4. Stratification according to alcohol intake, both current and cumulative as estimated by LACU, showed that very low consumers (C1 and Q1-Q3) displayed lower frequency of cirrhosis and hepatocellular carcinoma compared to abstainers and moderate consumers (C2 and Q4). We can speculate that up to one glass of wine daily in the context of a Mediterranean diet may be a long-term useful approach in selected NAFLD patients.

Association Between Monocyte to High-Density Lipoprotein Cholesterol Ratio and Risk of Non-alcoholic Fatty Liver Disease: A Cross-Sectional Study

Background

Non-alcoholic fatty liver disease (NAFLD) is a global health problem affecting more than a quarter of the entire adult population. Both monocytes and high-density lipoprotein cholesterol (HDL-C) were found to participate in the progression of hepatic inflammation and oxidative stress. We speculated that the monocyte-to-HDL-C ratio (MHR) may be associated with the risk of NAFLD.

Methods

We conducted a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) 2017-2018. NAFLD was identified using a controlled attenuation parameter (CAP) of ≥274 dB/m. Degree of liver fibrosis were assessed by liver stiffness measurement (LSM) and LSM values≥8.0, ≥ 9.7, and ≥13.7 kPa were defined as significant fibrosis (≥F2), advanced fibrosis (≥F3) and cirrhosis (F4), respectively. The association between MHR and the risk of NAFLD and liver fibrosis was estimated using weighted multivariable logistic regression. The non-linear relationship between MHR and the risk of NAFLD was further described using smooth curve fittings and threshold effect analysis.

Results

Of 4,319 participants, a total of 1,703 (39.4%) participants were diagnosed with NAFLD. After complete adjustment for potential confounders, MHR was positively associated with the risk of NAFLD (OR = 2.87, 95% CI: 1.95-4.22). The risk of NAFLD increased progressively as the MHR quarter increased (P for trend < 0.001). In subgroup analysis stratified by sex, a positive association existed in both sexes; Women displayed higher risk (men: OR = 2.12, 95% CI: 1.33-3.39; women: OR = 2.64, 95%CI: 1.40-4.97). MHR was positively associated with the risk of significant liver fibrosis (OR = 1.60, 95% CI: 1.08-2.37) and cirrhosis (OR = 1.83, 95% CI: 1.08-3.13), but not with advanced liver fibrosis (OR = 1.53, 95% CI: 0.98-2.39) after full adjustment for potential confounders. In the subgroup analysis by sex, the association between MHR and different degrees of liver fibrosis was significantly positive in women. When analyzing the relationship between MHR and NAFLD risk, a reverse U-shaped curve with an inflection point of 0.36 for MHR was found in women.

Conclusion

Higher MHR was associated with increased odds of NAFLD among Americans of both sexes. However, an association between MHR and liver fibrosis was found mainly among women.

Oxidative Stress in Metabolic and Endocrine Diseases: Basic and Translational Aspects

The aim of this Special Issue is to highlight oxidative stress (OS) as a mechanism underlying a major risk factor for several human diseases [...]

Pathophysiological Mechanisms in Non-Alcoholic Fatty Liver Disease: From Drivers to Targets

Non-alcoholic fatty liver disease (NAFLD) is characterized by the excessive and detrimental accumulation of liver fat as a result of high-caloric intake and/or cellular and molecular abnormalities. The prevalence of this pathological event is increasing worldwide, and is intimately associated with obesity and type 2 diabetes mellitus, among other comorbidities. To date, only therapeutic strategies based on lifestyle changes have exhibited a beneficial impact on patients with NAFLD, but unfortunately this approach is often difficult to implement, and shows poor long-term adherence. For this reason, great efforts are being made to elucidate and integrate the underlying pathological molecular mechanism, and to identify novel and promising druggable targets for therapy. In this regard, a large number of clinical trials testing different potential compounds have been performed, albeit with no conclusive results yet. Importantly, many other clinical trials are currently underway with results expected in the near future. Here, we summarize the key aspects of NAFLD pathogenesis and therapeutic targets in this frequent disorder, highlighting the most recent advances in the field and future research directions.

Inflammation and Fibrogenesis in MAFLD: Role of the Hepatic Immune System

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) is the definition recently proposed to better circumscribe the spectrum of conditions long known as non-alcoholic fatty liver disease (NAFLD) that range from simple steatosis without inflammation to more advanced liver diseases. The progression of MAFLD, as well as other chronic liver diseases, toward cirrhosis, is driven by hepatic inflammation and fibrogenesis. The latter, result of a "chronic wound healing reaction," is a dynamic process, and the understanding of its underlying pathophysiological events has increased in recent years. Fibrosis progresses in a microenvironment where it takes part an interplay between fibrogenic cells and many other elements, including some cells of the immune system with an underexplored or still unclear role in liver diseases. Some therapeutic approaches, also acting on the immune system, have been probed over time to evaluate their ability to improve inflammation and fibrosis in NAFLD, but to date no drug has been approved to treat this condition. In this review, we will focus on the contribution of the liver immune system in the progression of NAFLD, and on therapies under study that aim to counter the immune substrate of the disease.

Involvement of Ceramides in Non-Alcoholic Fatty Liver Disease (NAFLD) Atherosclerosis (ATS) Development: Mechanisms and Therapeutic Targets

Non-alcoholic fatty liver disease (NAFLD) and atherosclerosis (ATS) are worldwide known diseases with increased incidence and prevalence. These two are driven and are interconnected by multiple oxidative and metabolic functions such as lipotoxicity. A gamut of evidence suggests that sphingolipids (SL), such as ceramides, account for much of the tissue damage. Although in humans they are proving to be accurate biomarkers of adverse cardiovascular disease outcomes and NAFLD progression, in rodents, pharmacological inhibition or depletion of enzymes driving de novo ceramide synthesis prevents the development of metabolic driven diseases such as diabetes, ATS, and hepatic steatosis. In this narrative review, we discuss the pathways which generate the ceramide synthesis, the potential use of circulating ceramides as novel biomarkers in the development and progression of ATS and related diseases, and their potential use as therapeutic targets in NAFDL-ATS development which can further provide new clues in this field.

Regulation of hepatic fibrosis by carcinoembryonic antigen-related cell adhesion molecule 1

OBJECTIVE

NAFLD is a complex disease marked by cellular abnormalities leading to NASH. NAFLD patients manifest low hepatic levels of CEACAM1, a promoter of insulin clearance. Consistently, Cc1^-/- null mice displayed spontaneous hyperinsulinemia/insulin resistance and steatohepatitis. Liver-specific reconstitution of Ceacam1 reversed these metabolic anomalies in 8-month-old Cc1^-/-xliver+ mice fed a regular chow diet. The current study examined whether it would also reverse progressive hepatic fibrosis in mice fed a high-fat (HF) diet.

METHODS

3-Month-old mice were fed a high-fat diet for 3-5 months, and metabolic and histopathological analysis were conducted to evaluate their NASH phenotype.

RESULTS

Reconstituting CEACAM1 to Cc1^-/- livers curbed diet-induced liver dysfunction and NASH, including macrovesicular steatosis, lobular inflammation, apoptosis, oxidative stress, and chicken-wire bridging fibrosis. Persistence of hepatic fibrosis in HF-fed Cc1^-/- treated with nicotinic acid demonstrated a limited role for lipolysis and adipokine release in hepatic fibrosis caused by Ceacam1 deletion.

CONCLUSIONS

Restored metabolic and histopathological phenotype of HF-fed Cc1^{-/-xliver+xliver+} assigned a critical role for hepatic CEACAM1 in preventing NAFLD/NASH including progressive hepatic fibrosis.

The Agonists of Peroxisome Proliferator-Activated Receptor-γ for Liver Fibrosis

Liver fibrosis is a common link in the transformation of acute and chronic liver diseases to cirrhosis. It is of great clinical significance to study the factors associated with the induction of liver fibrosis and elucidate the method of reversal. Peroxisome proliferator-activated receptors (PPARs) are a class of nuclear transcription factors that can be activated by peroxisome proliferators. PPARs play an important role in fibrosis of various organs, especially the liver, by regulating downstream targeted pathways, such as TGF-β, MAPKs, and NF-κB p65. In recent years, the development and screening of PPAR-γ ligands have become a focus of research. The PPAR-γ ligands include synthetic hypolipidemic and antidiabetic drugs. In addition, microRNAs, lncRNAs, circRNAs and nano new drugs have attracted research interest. In this paper, the research progress of PPAR-γ in the pathogenesis and treatment of liver fibrosis was discussed based on the relevant literature in recent years.

Exploring the Protective Effects and Mechanism of Crocetin From Saffron Against NAFLD by Network Pharmacology and Experimental Validation

Background: Non-alcoholic fatty liver disease (NAFLD) is a burgeoning health problem but no drug has been approved for its treatment. Animal experiments and clinical trials have demonstrated the beneficial of saffron on NAFLD. However, the bioactive ingredients and therapeutic targets of saffron on NAFLD are unclear. Purpose: This study aimed to identify the bioactive ingredients of saffron responsible for its effects on NAFLD and explore its therapy targets through network pharmacology combined with experimental tests. Methods: Various network databases were searched to identify bioactive ingredients of saffron and identify NAFLD-related targets. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were conducted to enrich functions and molecular pathways of common targets and the STRING database was used to establish a protein-protein interaction network (PPI). The effect of crocetin (CCT) on NAFLD was evaluated in a mouse model of NAFLD by measuring the biomarkers of lipid, liver and renal function, oxidative stress, and inflammation. Liver histopathology was performed to evaluate liver injury. Nuclear factor erythroid-related factor (Nrf2) and hemeoxygenase-1 (HO-1) were examined to elucidate underlying mechanism for the protective effect of saffron against NAFLD. Results: A total of nine bioactive ingredients of saffron, including CCT, with 206 common targets showed therapeutic effects on NAFLD. Oxidative stress and diabetes related signaling pathways were identified as the critical signaling pathways mediating the therapeutic effects of the active bioactive ingredients on NAFLD. Treatment with CCT significantly reduced the activities of aspartate aminotransferase (AST), alanine transaminase (ALT), and the levels of total cholesterol (TC), triglyceride (TG), malondialdehyde (MDA), blood urea nitrogen (BUN), creatinine (CR), and uric acid (UA). CCT significantly increased the activities of superoxide dismutase (SOD), and catalase (CAT). Histological analysis showed that CCT suppressed high-fat diet (HFD) induced fat accumulation, steatohepatitis, and renal dysfunctions. Results of ELISA assay showed that CCT decreased the expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), and increased the expression of HO-1 and Nrf2. Conclusion: This study shows that CCT is a potential bioactive ingredient of saffron that treats NAFLD. Its mechanism of action involves suppressing of oxidative stress, mitigating inflammation, and upregulating Nrf2 and HO-1 expression.

Nutrigenomics and Nutrigenetics in Metabolic- (Dysfunction) Associated Fatty Liver Disease: Novel Insights and Future Perspectives

Metabolic- (dysfunction) associated fatty liver disease (MAFLD) represents the predominant hepatopathy and one of the most important systemic, metabolic-related disorders all over the world associated with severe medical and socio-economic repercussions due to its growing prevalence, clinical course (steatohepatitis and/or hepatocellular-carcinoma), and related extra-hepatic comorbidities. To date, no specific medications for the treatment of this condition exist, and the most valid recommendation for patients remains lifestyle change. MAFLD has been associated with metabolic syndrome; its development and progression are widely influenced by the interplay between genetic, environmental, and nutritional factors. Nutrigenetics and nutrigenomics findings suggest nutrition’s capability, by acting on the individual genetic background and modifying the specific epigenetic expression as well, to influence patients’ clinical outcome. Besides, immunity response is emerging as pivotal in this multifactorial scenario, suggesting the interaction between diet, genetics, and immunity as another tangled network that needs to be explored. The present review describes the genetic background contribution to MAFLD onset and worsening, its possibility to be influenced by nutritional habits, and the interplay between nutrients and immunity as one of the most promising research fields of the future in this context.

Nutrigenetic Interactions Might Modulate the Antioxidant and Anti-Inflammatory Status in Mastiha-Supplemented Patients With NAFLD

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease with no therapeutic consensus. Oxidation and inflammation are hallmarks in the progression of this complex disease, which also involves interactions between the genetic background and the environment. Mastiha is a natural nutritional supplement known to possess antioxidant and anti-inflammatory properties. This study investigated how a 6-month Mastiha supplementation (2.1 g/day) could impact the antioxidant and inflammatory status of patients with NAFLD, and whether genetic variants significantly mediate these effects. We recruited 98 patients with obesity (BMI ≥ 30 kg/m²) and NAFLD and randomly allocated them to either the Mastiha or the placebo group for 6 months. The anti-oxidative and inflammatory status was assessed at baseline and post-treatment. Genome-wide genetic data was also obtained from all participants, to investigate gene-by-Mastiha interactions. NAFLD patients with severe obesity (BMI > 35kg/m²) taking the Mastiha had significantly higher total antioxidant status (TAS) compared to the corresponding placebo group (P value=0.008). We did not observe any other significant change in the investigated biomarkers as a result of Mastiha supplementation alone. We identified several novel gene-by-Mastiha interaction associations with levels of cytokines and antioxidant biomarkers. Some of the identified genetic loci are implicated in the pathological pathways of NAFLD, including the lanosterol synthase gene (LSS) associated with glutathione peroxidase activity (Gpx) levels, the mitochondrial pyruvate carrier-1 gene (MPC1) and the sphingolipid transporter-1 gene (SPNS1) associated with hemoglobin levels, the transforming growth factor‐beta‐induced gene (TGFBI) and the micro-RNA 129-1 (MIR129-1) associated with IL-6 and the granzyme B gene (GZMB) associated with IL-10 levels. Within the MAST4HEALTH randomized clinical trial (NCT03135873, www.clinicaltrials.gov) Mastiha supplementation improved the TAS levels among NAFLD patients with severe obesity. We identified several novel genome-wide significant nutrigenetic interactions, influencing the antioxidant and inflammatory status in NAFLD.

The Role of Fructose in Non-Alcoholic Steatohepatitis: Old Relationship and New Insights

Non-alcoholic fatty liver disease (NAFLD) represents the result of hepatic fat overload not due to alcohol consumption and potentially evolving to advanced fibrosis, cirrhosis, and hepatocellular carcinoma. Fructose is a naturally occurring simple sugar widely used in food industry linked to glucose to form sucrose, largely contained in hypercaloric food and beverages. An increasing amount of evidence in scientific literature highlighted a detrimental effect of dietary fructose consumption on metabolic disorders such as insulin resistance, obesity, hepatic steatosis, and NAFLD-related fibrosis as well. An excessive fructose consumption has been associated with NAFLD development and progression to more clinically severe phenotypes by exerting various toxic effects, including increased fatty acid production, oxidative stress, and worsening insulin resistance. Furthermore, some studies in this context demonstrated even a crucial role in liver cancer progression. Despite this compelling evidence, the molecular mechanisms by which fructose elicits those effects on liver metabolism remain unclear. Emerging data suggest that dietary fructose may directly alter the expression of genes involved in lipid metabolism, including those that increase hepatic fat accumulation or reduce hepatic fat removal. This review aimed to summarize the current understanding of fructose metabolism on NAFLD pathogenesis and progression.

Therapeutic effects of myocardin-related transcription factor A (MRTF-A) knockout on experimental mice with nonalcoholic steatohepatitis induced by high-fat diet

OBJECTIVE

To explore the effects of myocardin-related transcription factor A (MRTF-A) knockout on mice with nonalcoholic steatohepatitis (NASH) induced by high-fat diet (HFD).

METHODS

Normal-fat diet (NFD) or HFD was fed to MRTF-A-knockout (MRTF-A^-/-) and wild-type (WT) mice for 16 weeks. Liver histopathological status was observed using Hematoxylin and Eosin (HE) staining, Oil Red O staining, Sirius Red staining, and Immunohistochemical staining. The mRNA and protein levels in liver tissues were measured through quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot.

RESULTS

Compared with WT + HFD group, mice in MRTF-A^-/- + HFD group were decreased in body weight, blood glucose, plasma insulin, liver TG and NAFLD activity score (NAS), with liver function recovery. Besides, compared with HFD-fed WT mice, HFD-fed MRTF-A^-/- mice were improved in hepatic fibrosis, accompanied by decreased collagen content (%) and down-regulated expressions of α-SMA, COL1A2, TGFβ1, and SMAD3. In mice fed with HFD, the expression of MCP-1, CCR2, F4/80 and CD68 declined in liver tissues of MRTF-A^-/- mice as compared with WT mice. Besides, in hepatic macrophages isolated from HFD-fed mice, the observed increased expression of TNF-α, IL-1β, MCP-1, as well as decreased expression of CCR2. Compared with WT + HFD group, MRTF-A^-/- + HFD group mice were decreased regarding NF-κB p65 in liver tissues.

CONCLUSION

MRTF-A knockout reduced macrophage infiltration, down-regulated NF-κB p65 expression, and ameliorated inflammation and fibrosis of liver tissues in mice, thereby becoming a potential therapeutic target for NASH treatment.

A Novel Nutraceuticals Mixture Improves Liver Steatosis by Preventing Oxidative Stress and Mitochondrial Dysfunction in a NAFLD Model

Non-alcoholic fatty liver disease (NAFLD) is the leading cause of liver disease globally, and represents a health care burden as treatment options are very scarce. The reason behind the NAFLD progression to non-alcoholic steatohepatitis (NASH) is not completely understood. Recently, the deficiency of micronutrients (e.g., vitamins, minerals, and other elements) has been suggested as crucial in NAFLD progression, such that recent studies reported the potential hepatic antioxidant properties of micronutrients supplementation. However, very little is known. Here we have explored the potential beneficial effects of dietary supplementation with FLINAX, a novel mixture of nutraceuticals (i.e., vitamin E, vitamin D3, olive dry-extract, cinnamon dry-extract and fish oil) in a NAFLD model characterized by oxidative stress and mitochondrial function impairment. Steatosis was firstly induced in Wistar rats by feeding with a high-fat/high-cholesterol diet for 4 weeks, and following this the rats were divided into two groups. One group (n = 8) was treated for 2 weeks with a normal chow-diet, while a second group (n = 8) was fed with a chow-diet supplemented with 2% FLINAX. Along with the entire experiment (6 weeks), a third group of rats was fed with a chow-diet only as control. Statistical analysis was performed with Student's T test or one-way ANOVA followed by post-hoc Bonferroni test when appropriate. Steatosis, oxidative stress and mitochondrial respiratory chain (RC) complexes activity were analyzed in liver tissues. The dietary supplementation with FLINAX significantly improved hepatic steatosis and lipid accumulation compared to untreated rats. The mRNA and protein levels analysis showed that CPT1A and CPT2 were up-regulated by FLINAX, suggesting the enhancement of fatty acids oxidation (FAO). Important lipoperoxidation markers (i.e., HNE- and MDA-protein adducts) and the quantity of total mitochondrial oxidized proteins were significantly lower in FLINAX-treated rats. Intriguingly, FLINAX restored the mitochondrial function, stimulating the activity of mitochondrial RC complexes (i.e., I, II, III and ATP-synthase) and counteracting the peroxide production from pyruvate/malate (complex I) and succinate (complex II). Therefore, the supplementation with FLINAX reprogrammed the cellular energy homeostasis by restoring the efficiency of mitochondrial function, with a consequent improvement in steatosis.