Serum zinc level and hepatic fibrosis in patients with nonalcoholic fatty liver disease

A randomized clinical study to evaluate the possible antifibrotic effect of zinc sulfate in chronic HCV patient receiving direct-acting anti-viral therapy

OBJECTIVE

This study aimed to assess the potential antifibrotic impact of zinc sulfate in chronic Hepatitis C Virus (HCV) patients receiving direct-acting antiviral therapy.

METHODS

This randomized controlled study included 50 chronic HCV-infected patients with fibrosis stage (F1 & F2). Participants were randomly assigned to two groups: Group 1 (Control group, n = 25) received standard direct-acting antiviral therapy for 3 months, while Group 2 (Zinc group, n = 25) received 50 mg/day of zinc sulfate in addition to the standard direct-acting antiviral therapy for the same duration. Baseline and 3-month post-intervention assessments included evaluating serum levels of hyaluronic acid, transforming growth factor beta-1, and fibronectin. Furthermore, indices of liver fibrosis, such as the Fibrosis Index based on the 4 factors (FIB-4) and the Aspartate Transaminase-to-Platelet-Ratio Index (APRI), were calculated during these assessments.

RESULTS

At baseline, the two studied groups had no statistical difference in demographic and laboratory data. After treatment, serum zinc levels significantly increased in the zinc-treated group compared to the control group. Additionally, serum fibronectin and hyaluronic acid levels were significantly reduced in group 2 (zinc group) compared to group 1 (control group). Moreover, zinc group showed lower APRI scores than the control group after a 3-month follow-up period, but there was non-significant difference in FIB-4 scores between the two groups after treatment. Furthermore, total bilirubin levels were reduced after zinc therapy for 3 months.

CONCLUSIONS

Administering zinc sulfate could potentially serve as a safe and efficient therapeutic strategy for the management of hepatic fibrosis in individuals with chronic hepatitis C virus.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT05465434, On 19/7/2022.

Zinc supplementation to improve prognosis in patients with compensated advanced chronic liver disease: a multicenter, randomized, double-blind, placebo-controlled clinical trial

Zinc homeostasis could play a role in compensated advanced chronic liver disease, and its supplementation has been linked to improvement in liver function, a decrease of hepatic complications, and reduction in HCC incidence. Compensated advanced chronic liver disease encompasses a heterogeneous group of patients with variable risks of clinically significant portal hypertension and clinical events. The ANTICIPATE model is a validated model for stratifying these risks. Our aim is to demonstrate that zinc administration can reduce the rate and risk of presenting clinical events (first decompensation, HCC, death, and liver transplantation). This study protocol describes an ongoing phase III, national, multicenter, randomized, double-blind clinical trial that will enroll 300 patients to receive either the trial treatment (zinc acexamate) or placebo. An inclusion period of 42 months is planned, with a minimum follow-up of 2 years. Our principal hypothesis is that zinc could modify the natural history of patients with compensated advanced chronic liver disease, with an overall improvement in prognosis.

Association Between Serum Zinc and Non-Alcoholic Fatty Liver Disease and Advanced Liver Fibrosis: NHANES 2011-2016

Limited and inconclusive evidence exists regarding the correlation between serum zinc levels and non-alcoholic fatty liver disease (NAFLD) and advanced fibrosis. The objective of this cross-sectional study was to investigate the association between serum zinc concentration and both NAFLD and advanced liver fibrosis among the United States (US) adults. 3398 subjects from National Health and Nutrition Examination Survey (NHANES) 2011-2016 were included. Serum zinc concentration was measured by inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS). NAFLD was diagnosed with Hepatic Steatosis Index (HSI), and advanced fibrosis risk was assessed by NAFLD Fibrosis Score (NFS). Weighted logistic regression and restricted cubic splines (RCS) were used to examine the association between serum zinc concentration and NAFLD and advanced fibrosis. Linear trend tests were conducted by incorporating the median of serum zinc quartiles as a continuous variable in the models. We employed sensitivity analysis and subgroup analysis to enhance the robustness of our results. The results from the RCS regression revealed no evident nonlinear relationship between serum zinc concentration and the presence of NAFLD and advanced fibrosis (p-nonlinear > 0.05). Compared with those in the lowest quartile (Q1) of serum zinc concentrations, the odds ratios (95% confidence intervals) of NAFLD were 1.49 (0.89,2.49) in Q2, 0.99 (0.68,1.45) in Q3, and 2.00 (1.40,2.86) in Q4 (p-trend = 0.002). Similarly, the odds ratios (95% confidence intervals) for advanced fibrosis in Q2-4 compared to Q1 were 0.86 (0.50,1.47), 0.60 (0.26,1.39), and 0.41 (0.21,0.77), respectively (p-trend = 0.006). Subgroup analyses and sensitivity analyses reinforce the same conclusion. The investigation revealed a positive linear relationship between serum zinc concentrations and the probability of developing NAFLD. Conversely, an inverse correlation was observed between serum zinc concentrations and the incidence of advanced liver fibrosis among individuals diagnosed with NAFLD.

Association between serum trace element, mineral, and amino acid levels with non-alcoholic fatty liver disease (NAFLD) in adult women

The objective of the present study is assessment of serum trace element and amino acid levels in non-alcoholic fatty liver disease (NAFLD) patients with subsequent evaluation of its independent associations with markers of liver injury and metabolic risk.

MATERIALS AND METHODS

140 women aged 20-90 years old with diagnosed NAFLD and 140 healthy women with a respective age range were enrolled in the current study. Analysis of serum and hair levels of trace elements and minerals was performed with inductively-coupled plasma mass-spectrometry (ICP-MS). Serum amino acid concentrations were evaluated by high-pressure liquid chromatography (HPLC) with UV-detection. In addition, routine biochemical parameters including liver damage markers, alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT), were assessed spectrophotometrically.

RESULTS

The findings demonstrated that patients with NAFLD were characterized by higher ALT, GGT, lactate dehydrogenase (LDH) and cholinesterase (CE) activity, as well as increased levels of total cholesterol, low-density lipoprotein cholesterol, triglycerides, and uric acid. NAFLD patients were characterized by reduced serum and hair Co, Se, and Zn levels, as well as hair Cu content and serum Mn concentrations in comparison to controls. Circulating Ala, Cit, Glu, Gly, Ile, Leu, Phe, and Tyr levels in NAFLD patients exceeded those in the control group. Multiple linear regression demonstrated that serum and hair trace element levels were significantly associated with circulating amino acid levels after adjustment for age, BMI, and metabolic parameters including liver damage markers.

CONCLUSION

It is proposed that altered trace element handling may contribute to NAFLD pathogenesis through modulation of amino acid metabolism.

Supplementation of Micro- and Macronutrients-A Role of Nutritional Status in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a condition in which the pathological cumulation of fat with coexisting inflammation and damage of hepatic cells leads to progressive dysfunctions of the liver. Except for the commonly well-known major causes of NAFLD such as obesity, dyslipidemia, insulin resistance, or diabetes, an unbalanced diet and imbalanced nutritional status should also be taken into consideration. In this narrative review, we summarized the current knowledge regarding the micro- and macronutrient status of patients suffering from NAFLD considering various diets and supplementation of chosen supplements. We aimed to summarize the knowledge indicating which nutritional impairments may be associated with the onset and progression of NAFLD at the same time evaluating the potential therapy targets that could facilitate the healing process. Except for the above-mentioned objectives, one of the most important aspects of this review was to highlight the possible strategies for taking care of NAFLD patients taking into account the challenges and opportunities associated with the micronutrient status of the patients. The current research indicates that a supplementation of chosen vitamins (e.g., vitamin A, B complex, C, or D) as well as chosen elements such as zinc may alleviate the symptoms of NAFLD. However, there is still a lack of sufficient data regarding healthy ranges of dosages; thus, further research is of high importance in this matter.

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.

Serum zinc concentration as a potential predictor of presarcopenia in patients with chronic liver disease: a preliminary study

BACKGROUND

Presarcopenia is a common complication of chronic liver disease. However, the relationship between serum zinc concentration and presarcopenia in patients with chronic liver disease remains unclear. Herein, we examined whether serum zinc concentration could predict presarcopenia in patients with chronic liver disease.

METHODS

Between October 2015 and December 2019, 278 patients with chronic liver disease (median age, 68 years; women/men, 133/145; hepatitis B virus/hepatitis C virus/negative hepatitis B surface antigen and negative anti-hepatitis C virus antibody, 55/124/99) who underwent abdominal computed tomography (CT) and simultaneous measurement of serum zinc concentration were included. Zinc deficiency and subclinical zinc deficiency were classified using serum zinc concentration cutoff values of <60 and <80 μg/dL [based on the Japanese Society of Clinical Nutrition (JSCN) guidelines], respectively. Additionally, presarcopenia was evaluated based on the skeletal muscle mass as per the Japan Society of Hepatology (JSH)'s sarcopenia criteria.

RESULTS

Univariate analysis revealed that the following factors were significantly associated with the presence of presarcopenia in patients with chronic liver disease: age (P<0.001), male sex (P<0.001), body mass index (BMI) (P<0.001), serum zinc concentration (P=0.005), fibrosis-4 index (P<0.001), and serum albumin concentration (P=0.03). Additionally, the median L3 skeletal muscle indices were as follows: men, non-presarcopenia group/presarcopenia group, 47.56/37.91 cm2/m2 (P<0.001); women, non-presarcopenia group/presarcopenia group, 41.64/32.88 cm2/m2 (P<0.001). Multivariate analysis using logistic regression analysis revealed that male sex [odds ratio (OR), 0.194; 95% confidence interval (CI): 0.089-0.419; P<0.001], BMI (OR, 0.666; 95% CI: 0.582-0.761; P<0.001), and serum zinc concentration <60 μg/dL (OR, 5.930; 95% CI: 1.480-23.80; P=0.01) were factors associated with presarcopenia. The OR for serum zinc concentration between 60 and 80 μg/dL was 1.910 (95% CI: 0.824-4.420; P=0.13).

CONCLUSIONS

Low serum zinc levels may be an independent predictor of presarcopenia in patients with chronic liver disease.

Association of whole blood copper, zinc, calcium, magnesium, and iron with non-alcoholic fatty liver disease in overweight and obese children

OBJECTIVES

Non-alcoholic fatty liver disease (NAFLD) is a common metabolic disorder in overweight and obese children, and its etiology and pathogenesis remain unclear, lacking effective preventive and therapeutic measures. This study aims to explore the association between whole blood copper, zinc, calcium, magnesium and iron levels and NAFLD in overweight and obese children aged 6 to 17 years, providing a scientific basis for the prevention and intervention of early NAFLD in overweight and obese children.

METHODS

A cross-sectional study design was used to collect relevant data from overweight and obese children who visited the Hunan Children's Hospital from January 2019 to December 2021 through questionnaire surveys. Fasting blood samples were collected from the subjects, and various indicators such as blood glucose, blood lipid, and mineral elements were detected. All children were divided into an overweight group (n=400) and a NAFLD group (n=202). The NAFLD group was divided into 2 subgroups according to the ALT level: A non-alcoholic fatty liver (NAFL) group and a non-alcoholic steatohepatitis (NASH) group. Logistic regression analysis was used to analyze the association between minerals (copper, zinc, calcium, magnesium, and iron) and NAFLD, NAFL and NASH.

RESULTS

A total of 602 subjects were included, of whom 73.6% were male, with a median age of 10 (9, 11) years, and a body mass index (BMI) of 24.9 (22.7, 27.4) kg/m2. The intergroup comparison results showed that compared with the overweight group, the NAFLD group had higher levels of age, BMI, diastolic blood pressure (DBP), systolic blood pressure (SBP), triglyceride (TG), low density lipoprotein (LDL), alanine transaminase (ALT) and aspartate aminotransferase (AST), and lower level of high density lipoprotein (HDL). The NAFL group had higher levels of age, BMI, DBP, SBP, ALT, and AST, and lower levels of HDL compared with the overweight group. The levels of age, BMI, DBP, SBP, TG, LDL, ALT, and AST of NASH were higher than those in the overweight group, while the level of HDL was lower than that in overweight group (all P<0.017). After adjusting for a variety of confounders, the OR of NAFLD for the highest quantile of iron was 1.79 (95% CI 1.07 to 3.00) compared to the lowest quantile, and no significant association was observed between copper, zinc, calcium, and magnesium, and NAFLD. The subgroup analysis of NAFLD showed that the OR for the highest quantile of iron in children with NAFL was 2.21 (95% CI 1.26 to 3.88), while no significant association was observed between iron level and NASH. In addition, no significant associations were observed between copper, zinc, calcium, and magnesium levels and NAFL or NASH.

CONCLUSIONS

High iron level increases the risk of NAFLD (more likely NAFL) in overweight and obese children, while copper, zinc, calcium, magnesium, and other elements are not associated with the risk of NAFLD in overweight and obese children.

Exploring the interactions between metabolic dysfunction-associated fatty liver disease and micronutrients: from molecular mechanisms to clinical applications

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) has emerged as a significant global health concern, representing a major cause of liver disease worldwide. This condition spans a spectrum of histopathologic stages, beginning with simple fatty liver (MAFL), characterized by over 5% fat accumulation, and advancing to metabolic (dysfunction)-associated steatohepatitis, potentially leading to hepatocellular carcinoma. Despite extensive research, there remains a substantial gap in effective therapeutic interventions. This condition's progression is closely tied to micronutrient levels, crucial for biological functions like antioxidant activities and immune efficiency. The levels of these micronutrients exhibit considerable variability among individuals with MAFLD. Moreover, the extent of deficiency in these nutrients can vary significantly throughout the different stages of MAFLD, with disease progression potentially exacerbating these deficiencies. This review focuses on the role of micronutrients, particularly vitamins A, D, E, and minerals like iron, copper, selenium, and zinc, in MAFLD's pathophysiology. It highlights how alterations in the homeostasis of these micronutrients are intricately linked to the pathophysiological processes of MAFLD. Concurrently, this review endeavors to harness the existing evidence to propose novel therapeutic strategies targeting these vitamins and minerals in MAFLD management and offers new insights into disease mechanisms and treatment opportunities in MAFLD.

Zinc supplementation with polaprezinc was associated with improvements in albumin, prothrombin time activity, and hemoglobin in chronic liver disease

Zinc deficiency occurs in a variety of diseases, including chronic liver disease (CLD). We investigated the correlation between zinc levels and biochemical and hematological tests in CLD and the effect of zinc supplementation with polaprezinc on these values. The first study (Study 1) was a retrospective observational study of 490 patients with CLD not receiving zinc supplementation, with data available from September 2009 to August 2021. Univariate and multiple regression analysis showed that serum zinc levels correlated most strongly with albumin (Alb) and also significantly with prothrombin time activity (PT%) and hemoglobin (Hb). A subsequent study (Study 2) focused on patients with advanced CLD who used polaprezinc for more than 90 days between January 2005 and August 2021. Using a self-controlled design with the 6-month period prior to polaprezinc as the control period, comparisons showed that Alb (p<0.0001), PT% (p<0.0005), and Hb (p<0.01) were significantly improved in the polaprezinc-treated patients compared to the control group. In conclusion, serum zinc levels were correlated with serum Alb, Hb, and PT% in patients with CLD, and zinc supplementation with polaprezinc was associated with improvements in Alb, Hb, and PT% within at least 6 months.

Association Between Non-alcoholic Fatty Liver Disease and Heavy Metal Exposure: a Systematic Review

Non-alcoholic fatty liver disease (NAFLD) is a debilitating disease with adverse effects including cirrhosis and hepatocellular carcinoma. Heavy metals can cause severe dysfunction in different body organs including the liver. This review offers the study regarding the positive or negative association between heavy metals exposure and non-alcoholic fatty liver disease. The method used in this study is a systematic review based on searching in the PubMed, Scopus, and Science direct databases with the keywords of fatty liver, non-alcohol fatty liver, heavy metal, mercury, cadmium, arsenic, chromium, thallium, lead, iron, zinc, and nickel. There were 2200 articles searched in databases, and after assessment, 28 articles were selected. Positive association is established between arsenic, cadmium, iron, lead, mercury, and fatty liver disease. A negative relationship is found between zinc, copper, and progressive fatty liver disease. Furthermore, laboratory methods for NAFLD diagnosis were examined according to the obtained manuscripts. Among the different diagnostic methods, magnetic resonance imaging (MRI) is a sensitive method.

Biomarkers of Micronutrients and Phytonutrients and Their Application in Epidemiological Studies

Nutritional biomarkers can be used as important indicators of nutritional status and play crucial roles in the prevention as well as prognosis optimization of various metabolism-related diseases. Measuring dietary with the deployment of biomarker assessments provides quantitative nutritional information that can better predict the health outcomes. With the increased availability of nutritional biomarkers and the development of assessment tools, the specificity and sensitivity of nutritional biomarkers have been greatly improved. This enables efficient disease surveillance in nutrition research. A wide range of biomarkers have been used in different types of studies, including clinical trials, observational studies, and qualitative studies, to reflect the relationship between diet and health. Through a comprehensive literature search, we reviewed the well-established nutritional biomarkers of vitamins, minerals, and phytonutrients, and their association with epidemiological studies, to better understand the role of nutrition in health and disease.

Serum zinc levels in cancer patients are low and difficult to elevate when complicated by liver cirrhosis: A retrospective study

In this study, we analyzed blood zinc concentration in patients with various cancer types and the degree of improvement in relation to the underlying disease following treatment with zinc preparations. Serum zinc levels of 530 cancer patients whose blood zinc levels were measured at our hospital from 2016 to 2021 were retrospectively examined in accordance with the primary disease. Changes in zinc levels were analyzed in 155 patients whose zinc levels had been measured on 2 or more occasions in accordance with whether they had received zinc preparations. In addition, the concentration course of zinc before and after zinc formulation administration in 73 patients was examined in accordance with the presence or absence of liver cirrhosis complications. Mean serum zinc levels were below normal in all carcinomas measured, and zinc levels were significantly lower in cirrhosis-hepatocarcinoma cases than in other primary disease cases. Furthermore, serum zinc levels in patients who did not receive zinc preparations decreased significantly over time. In patients who received zinc preparations, the elevated levels of zinc after treatment were significantly lower in patients with cirrhosis than in those without cirrhosis. There was a weak inverse correlation between pre-dose zinc concentration and increased zinc concentration in patients with cirrhosis. In the analysis of covariance, the presence of liver cirrhosis was predominantly correlated with elevated zinc per dose. In summary, serum zinc levels in cancer patients are low and especially low in cancer patients with liver cirrhosis compared with those without cirrhosis after the administration of zinc preparations.

Recent advances in the application of ionomics in metabolic diseases

Trace elements and minerals play a significant role in human health and diseases. In recent years, ionomics has been rapidly and widely applied to explore the distribution, regulation, and crosstalk of different elements in various physiological and pathological processes. On the basis of multi-elemental analytical techniques and bioinformatics methods, it is possible to elucidate the relationship between the metabolism and homeostasis of diverse elements and common diseases. The current review aims to provide an overview of recent advances in the application of ionomics in metabolic disease research. We mainly focuses on the studies about ionomic or multi-elemental profiling of different biological samples for several major types of metabolic diseases, such as diabetes mellitus, obesity, and metabolic syndrome, which reveal distinct and dynamic patterns of ion contents and their potential benefits in the detection and prognosis of these illnesses. Accumulation of copper, selenium, and environmental toxic metals as well as deficiency of zinc and magnesium appear to be the most significant risk factors for the majority of metabolic diseases, suggesting that imbalance of these elements may be involved in the pathogenesis of these diseases. Moreover, each type of metabolic diseases has shown a relatively unique distribution of ions in biofluids and hair/nails from patients, which might serve as potential indicators for the respective disease. Overall, ionomics not only improves our understanding of the association between elemental dyshomeostasis and the development of metabolic disease but also assists in the identification of new potential diagnostic and prognostic markers in translational medicine.

Can Zinc Supplementation Attenuate High Fat Diet-Induced Non-Alcoholic Fatty Liver Disease?

The pathogenesis of non-alcoholic fatty liver disease (NAFLD), the most prevalent chronic liver disease, is associated with zinc deficiency. Previous studies show zinc supplementation improves steatosis and glucose metabolism, but its therapeutic effects in patients with established NAFLD remain unclear. We developed an in vivo model to characterize the effects of zinc supplementation on high-fat diet (HFD) induced NAFLD and hypothesized that the established NAFLD would be attenuated by zinc supplementation. Male C57BL/6J mice were fed a control diet or HFD for 12 weeks. Mice were then further grouped into normal and zinc-supplemented diets for 8 additional weeks. Body composition and glucose tolerance were determined before and after zinc supplementation. At euthanasia, plasma and liver tissue were collected for characterization and downstream analysis. As expected, 12 weeks of HFD resulted in reduced glucose clearance and altered body composition. Eight weeks of subsequent zinc supplementation did not alter glucose handling, plasma transaminases, steatosis, or hepatic gene expression. Results from our model suggest 8-week zinc supplementation cannot reverse established NAFLD. The HFD may have caused NAFLD disease progression beyond rescue by an 8-week period of zinc supplementation. Future studies will address these limitations and provide insights into zinc as a therapeutic agent for established NAFLD.

Mineral metabolism and ferroptosis in non-alcoholic fatty liver diseases

Nonalcoholic fatty liver disease (NAFLD) has become the most prevalent chronic liver disease worldwide. Minerals including iron, copper, zinc, and selenium, fulfil an essential role in various biochemical processes. Moreover, the identification of ferroptosis and cuproptosis further underscores the importance of intracellular mineral homeostasis. However, perturbation of minerals has been frequently reported in patients with NAFLD and related diseases. Interestingly, studies have attempted to establish an association between mineral disorders and NAFLD pathological features, including oxidative stress, mitochondrial dysfunction, inflammatory response, and fibrogenesis. In this review, we aim to provide an overview of the current understanding of mineral metabolism (i.e., absorption, utilization, and transport) and mineral interactions in the pathogenesis of NAFLD. More importantly, this review highlights potential therapeutic strategies, challenges, future directions for targeting mineral metabolism in the treatment of NAFLD.

Serum sphingosine-1 phosphate level is increased in patients with hepatitis B and displays a positive association with liver fibrosis

OBJECTIVE

To investigate the difference in serum sphingosine-1 phosphate (S1P) concentration between the HBV hepatitis patients and healthy controls, and its relevant association with serum liver fibrosis indicators.

METHODS

A total of 28 HBsAg (+) HBeAg (+) Anti-HBc (+) hepatitis B patients, 42 HBsAg (+) Anti-HBe (+) Anti-HBc (+) hepatitis B patients, and 21 healthy subjects with normal liver function were included. Liquid chromatography-tandem mass method was used to detect the level of serum S1P.

RESULTS

SerumS1P concentration of Anti-HBe (+) hepatitis B patients was higher than that of the control group (P=0.017) and HBeAg (+) patients (P=0.007). At the same time, there was no significant difference in the serum S1P concentration between HBeAg (+) hepatitis B patients and the control group (P>0.05). Moreover, serum S1P concentration was positively correlated with liver fibrosis indices, Collage Type IV Protein (r=0.264; P=0.011), and Chitosanase 3-like protein 1 (r=0.295; P=0.004).

CONCLUSIONS

Serum S1P level is increased in patients with hepatitis B and displays a positive association with liver fibrosis.

Update on Non-Alcoholic Fatty Liver Disease-Associated Single Nucleotide Polymorphisms and Their Involvement in Liver Steatosis, Inflammation, and Fibrosis: A Narrative Review

Genetic factors are involved in the development, progression, and severity of NAFLD. Polymorphisms in genes regulating liver functions may increase liver susceptibility to NAFLD. Therefore, we conducted this literature study to present recent findings on NAFLD-associated polymorphisms from published articles in PubMed from 2016 to 2021. From 69 selected research articles, 20 genes and 34 SNPs were reported to be associated with NAFLD. These mutated genes affect NAFLD by promoting liver steatosis (PNPLA3, MBOAT7, TM2SF6, PTPRD, FNDC5, IL-1B, PPARGC1A, UCP2, TCF7L2, SAMM50, IL-6, AGTR1, and NNMT), inflammation (PNPLA3, TNF-α, AGTR1, IL-17A, IL-1B, PTPRD, and GATAD2A), and fibrosis (IL-1B, PNPLA3, MBOAT7, TCF7L2, GATAD2A, IL-6, NNMT, UCP, AGTR1, and TM2SF6). The identification of these genetic factors helps to better understand the pathogenesis pathways of NAFLD

A Specifically Tailored Multistrain Probiotic and Micronutrient Mixture Affects Nonalcoholic Fatty Liver Disease-Related Markers in Patients with Obesity after Mini Gastric Bypass Surgery

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is frequent among patients undergoing bariatric surgery. Beyond weight reduction, dietary supplements like micronutrients or probiotics that modify insulin resistance and lipotoxicity can be used to prevent or delay the progression of liver disease.

OBJECTIVES

We evaluated the effect of a dietary approach with a specifically tailored multistrain probiotic and micronutrient mixture compared with a basic care micronutrient supplement on serum alanine aminotransferase (ALAT) in obese patients after mini gastric bypass (MGB) surgery.

METHODS

This randomized, double-blind, controlled trial included 60 obese patients (age: 40 ± 10 y; BMI: 44 ± 3 kg/m²). Patients received a combination of specifically tailored multistrain probiotic powder and a specific micronutrient mixture (Pro+SM) or a control treatment consisting of a placebo and a basic care micronutrient mixture (Con+BM), with some micronutrients in lower doses than SM, for 12 wk after hospital discharge. Primary (serum ALAT) and secondary outcomes [serum aspartate aminotransferase (ASAT), fatty liver index, NAFLD fibrosis score, glucose metabolism, blood pressure (BP), heart rate] were assessed at week 0 and week 12. Data were analyzed using unpaired Student's t-tests or Mann-Whitney U tests to compare the changes due to each treatment to one another.

RESULTS

A total of 48 patients were included in the analyses. Changes in serum ALAT concentrations did not differ between groups. Compared with Con+BM, Pro+SM improved serum ASAT (difference: -8.0 U/L, 95% CI: -17.0, -4.0; P = 0.043), NAFLD fibrosis score (difference: -0.39; 95% CI: -0.78, 0; P = 0.048), serum triglycerides (difference: -22.8 mg/dL; 95% CI: -45.6, -0.1; P = 0.049) and the visceral adiposity index (difference: -0.70; 95% CI: -1.31, -0.08; P = 0.027).

CONCLUSION

Supplementation with a specifically tailored probiotic and micronutrient mixture improved NAFLD-related markers more than a basic micronutrient mixture in obese patients following MGB surgery. The trial was registered under clinicaltrials.gov as NCT03585413.

The role of zinc in the prevention and treatment of nonalcoholic fatty liver disease

The zinc element is an essential nutrient for human health. Zinc is involved in the glucose, lipid, and protein metabolism and antioxidant processes in biological pathways. Zinc deficiency can lead to several chronic liver diseases. Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases where zinc deficiency plays a critical role in pathogenesis. Human and animal studies showed that both NAFLD risk factors (i.e., insulin resistance, diabetes mellitus, dyslipidemia, obesity, hypertension) and NAFLD itself are associated with decreased blood levels of zinc. Additionally, endoplasmic reticulum stress and inflammation due to unfolded protein response, inadequate dietary zinc intake, and decreased zinc absorption from the gastrointestinal tract can result in zinc deficiency leading to NAFLD. Herein, we reviewed the mechanistic links between zinc deficiency and NAFLD development and the role of zinc in the prevention and treatment of NAFLD.

An improved production and purification protocol for recombinant soluble human fibroblast activation protein alpha

Fibroblast activation protein alpha (FAP) is a cell-surface expressed type II glycoprotein that has a unique proteolytic activity. FAP has active soluble forms that retain the extracellular portion but lack the transmembrane domain and cytoplasmic tail. FAP expression is normally very low in adult tissue but is highly expressed by activated fibroblasts in sites of tissue remodelling. Thus, FAP is a potential biomarker and pharmacological target in liver fibrosis, atherosclerosis, cardiac fibrosis, arthritis and cancer. Understanding the biological significance of FAP by investigating protein structure, interactions and activities requires reliable methods for the production and purification of abundant pure and stable protein. We describe an improved production and purification protocol for His₆-tagged recombinant soluble human FAP. A modified baculovirus expression construct was generated using the pFastBac1 vector and the gp67 secretion signal to produce abundant active soluble recombinant human FAP (residues 27-760) in insect cells. The FAP purification protocol employed ammonium sulphate precipitation, ion exchange chromatography, immobilised metal affinity chromatography and ultrafiltration. High purity was achieved, as judged by gel electrophoresis and specific activity. The purified 82 kDa FAP protein was specifically inhibited by a FAP selective inhibitor, ARI-3099, and was inhibited by zinc with an IC₅₀ of 25 μM. Our approach could be adopted for producing the soluble portions of other type II transmembrane glycoproteins to study their structure and function.