Severe Vitamin D Deficiency May be an Additional Cofactor for the Occurrence of Alcoholic Steatohepatitis

No causal relationship between serum vitamin D levels and alcoholic liver disease: a two-sample bidirectional Mendelian randomization study

Background

Numerous observational studies have presented an association between Vitamin D (VD) and Alcoholic Liver Disease (ALD). However, sufficient evidence from Randomized Controlled Trials (RCTs) substantiating this correlation is scarce, thus leaving the causality of this relationship ambiguous. To overcome the shortcomings of traditional observational studies, we performed a two-sample bidirectional Mendelian randomization (MR) analysis to ascertain the causal relationship between VD and ALD.

Methods

We utilized summary statistics datasets from Genome-Wide Association Studies (GWAS) for VD and ALD. We selected genetic instruments that measure circulating VD levels (n = 64,979), and retrieved ALD statistics from GWASs, inclusive of 1,416 cases and 217,376 healthy controls, while excluding chronic liver diseases such as nonalcoholic fatty liver disease, toxic liver disease, and viral hepatitis. Subsequent, MR analyses were performed to obtain effect estimates using inverse variance weighted (IVW) random effect models. Cochran's Q statistic and MR-Egger regression intercept analyses were used to assess pleiotropy. Sensitivity analyses using the MR Egger, weighted median, simple mode, and weighted mode methods were also performed. Leave-one-out analysis was used to identify SNPs with potential effect. Reverse MR analysis was also performed.

Results

In IVW, our MR analysis incorporated 21 independent SNPs, circulating VD levels had no causal effect on ALD [OR = 0.624 (0.336-1.160), p = 0.136] and ALD had no causal effect on circulating VD [OR = 0.997 (0.986-1.008), p = 0.555]. No heterogeneity or pleiotropy was observed (p > 0.05). Other MR methods also agreed with IVW results.

Conclusion

This study provides the causal relationship between genetically predicted circulating Vitamin D levels and ALD and provides new insights into the genetics of ALD.

Vitamin D Deficiency Is Associated with Advanced Liver Fibrosis and Impaired Fasting Glucose in Alcohol Use Disorder

BACKGROUND

Vitamin D deficiency is a risk factor for liver disease, insulin resistance, and beta cell dysfunction. Individuals with alcohol use disorder (AUD) have many comorbidities, with a heavy burden of liver disease and metabolic complications, including type 2 diabetes mellitus (T2DM).

OBJECTIVE

We aimed to analyze the prevalence and associations of vitamin D deficiency in patients admitted for in-hospital treatment of AUD.

METHODS

A cross-sectional study was conducted in patients consecutively admitted for the treatment of AUD between January 2017 and October 2023. Sociodemographic data, substance use characteristics, and blood parameters were available at admission. Vitamin D status was assessed through the serum concentrations of 25-hydroxyvitamin D [25(OH)D] levels using a direct competitive chemiluminescent immunoassay method. Deficiency of vitamin D was defined as a concentration less than 20 ng/mL; impaired fasting glucose (IFG) was defined by fasting blood glucose >100 mg/dL (5.6 mmol/L), and advanced liver fibrosis by an FIB-4 index >3.25.

RESULTS

Two hundred and forty-three patients were included (75% male) with a mean age of 49 ± 10 years, mean BMI of 26.4 ± 7.3, mean alcohol consumption of 163 ± 81 g/day, and a mean duration of AUD of 18.1 ± 11.2 years. Mean 25(OH)D, fasting blood glucose, AST, ALT, and platelets were 14.4 ± 10.2 ng/mL, 103.4 ± 40.9 mg/dL, 55.1 ± 75.8 U/L, 44.8 ± 76.6 U/L, and 206.3 ± 84.8 × 109/L, respectively. The prevalence of vitamin D deficiency was 80.6%, and 41.1% of patients had levels less than 10 ng/mL. IFG was present in 32.3% of patients, and 20.5% had FIB-4 values >3.25. In the multivariable analysis, IFG (OR, 2.51; 95% CI: 1.02-6.17, p = 0.04) and advanced liver fibrosis (OR, 4.27; 95% CI: 1.21-15.0, p = 0.02) were the only factors associated with vitamin D deficiency.

CONCLUSIONS

Vitamin D deficiency was very prevalent in this series of patients with AUD and was associated with impaired fasting glucose and advanced liver fibrosis.

Iron as a therapeutic target in chronic liver disease

It was clearly realized more than 50 years ago that iron deposition in the liver may be a critical factor in the development and progression of liver disease. The recent clarification of ferroptosis as a specific form of regulated hepatocyte death different from apoptosis and the description of ferritinophagy as a specific variation of autophagy prompted detailed investigations on the association of iron and the liver. In this review, we will present a brief discussion of iron absorption and handling by the liver with emphasis on the role of liver macrophages and the significance of the iron regulators hepcidin, transferrin, and ferritin in iron homeostasis. The regulation of ferroptosis by endogenous and exogenous mod-ulators will be examined. Furthermore, the involvement of iron and ferroptosis in various liver diseases including alcoholic and non-alcoholic liver disease, chronic hepatitis B and C, liver fibrosis, and hepatocellular carcinoma (HCC) will be analyzed. Finally, experimental and clinical results following interventions to reduce iron deposition and the promising manipulation of ferroptosis will be presented. Most liver diseases will be benefited by ferroptosis inhibition using exogenous inhibitors with the notable exception of HCC, where induction of ferroptosis is the desired effect. Current evidence mostly stems from in vitro and in vivo experimental studies and the need for well-designed future clinical trials is warranted.

Role of Vitamin D in Liver Disease and Complications of Advanced Chronic Liver Disease

Vitamin D is a crucial nutrient with many pleiotropic effects on health and various chronic diseases. The purpose of this review is to provide a detailed report on the pathophysiological mechanisms underlying vitamin D deficiency in patients with chronic liver disease, addressing the different liver etiologies and the condition of advanced chronic liver disease (cirrhosis) with related complications. To date, patients with liver disease, regardless of underlying etiology, have been shown to have reduced levels of vitamin D. There is also evidence of the predictive role of vitamin D values in complications and progression of advanced disease. However, specific indications of vitamin D supplementation are not conclusive concerning what is already recommended in the general population. Future studies should make an effort to unify and validate the role of vitamin D supplementation in chronic liver disease.

Iron-Induced Hepatocarcinogenesis—Preventive Effects of Nutrients

The liver is a primary organ that stores body iron, and plays a central role in the regulation of iron homeostasis. Hepatic iron overload (HIO) is a prevalent feature among patients with chronic liver diseases (CLDs), including alcoholic/nonalcoholic liver diseases and hepatitis C. HIO is suggested to promote the progression toward hepatocellular carcinoma because of the pro-oxidant nature of iron. Iron metabolism is tightly regulated by various factors, such as hepcidin and ferroportin, in healthy individuals to protect the liver from such deteriorative effects. However, their intrinsic expressions or functions are frequently compromised in patients with HIO. Thus, various nutrients have been reported to regulate hepatic iron metabolism and protect the liver from iron-induced damage. These nutrients are beneficial in HIO-associated CLD treatment and eventually prevent iron-mediated hepatocarcinogenesis. This mini-review aimed to discuss the mechanisms and hepatocarcinogenic risk of HIO in patients with CLDs. Moreover, nutrients that hold the potential to prevent iron-induced hepatocarcinogenesis are summarized.

Golden opportunity for intervention? Identifying vitamin D deficiency in patients with substance use disorders in hospital

Setting

Based at a busy city hospital, the alcohol care team is a drug and alcohol specialist service, taking referrals for a wide range of patients with substance use disorders (SUD).

Objectives

Patients with SUD are at high risk of vitamin D deficiency; this relates to frequent fractures and proximal myopathy. The coronavirus pandemic brought vitamin D into focus. Local guidelines advise that patients at high risk of vitamin D deficiency are offered replacement. There were no local data on vitamin D deficiency prevalence or any mention of patients with SUD in local vitamin D guidelines. The main aim of this project was to offer vitamin D checks and replacement to all appropriate patients.

Results

We collected data on 207 patients, [pilot study (n=50) and two subsequent samples (n=95 and n=62)]. Our pilot study showed that no patients were offered vitamin D testing or replacement. We then offered vitamin D checks to 95 patients. Most had low vitamin D (30 patients were vitamin D deficient and 26 were vitamin D insufficient). We provided vitamin D replacement and follow-up advice. Quality improvement was demonstrated 6 months later. We collected data on a further 62 patients who were all on our current or recent caseload. Following exclusions, nearly half (48%) of patients had had a vitamin D check. Almost all of these (95%) had low vitamin D (60% being classified as deficient).

Conclusions

Patients had not been offered vitamin D replacement despite often having multiple risk factors for vitamin D deficiency. Vitamin D checks (and subsequent replacement) rose in frequency since the outset of this project. Local guidelines should add SUD as a risk factor for vitamin D deficiency. Hospital admission provides a rich opportunity to offer this simple intervention to patients who are often poorly engaged with community services.

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

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

The effect of 1,25-dihydroxyvitamin D3 on liver damage, oxidative stress, and advanced glycation end products in experimental nonalcoholic- and alcoholic- fatty liver disease

Background/aim

Oxidative stress and advanced glycation end products (AGEs) formation are proposed as effective mechanisms in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD). 1,25(OH)2D3 was proposed to have antioxidant, antiinflammatory and antiglycation properties. In this study, the effect of 1,25(OH)2D3 treatment on oxidative stress parameters and AGEs levels together with hepatic histopathology was investigated in high fructose (HFr) or ethanol (EtOH)-treated rats.

Materials and methods

Rats were treated with fructose (30%) or ethanol (5-20%) in drinking water with and without 1,25(OH)2D3 treatment (5 µg/kg two times a week) for 8 weeks. Insulin resistance (IR), oxidative stress parameters, AGEs, triglyceride (TG), and hydroxyproline (Hyp) levels together with histopathology were investigated in the liver.

Results

1,25(OH)2D3 decreased hepatic reactive oxygen species, lipid and protein oxidation products together with histopathological improvements in HFr- and EtOH-treated rats. 1,25(OH)2D3 treatment was observed to decrease significantly serum and hepatic AGEs in HFr group, and hepatic AGEs in EtOH group.

Conclusion

Our results clearly show that 1,25(OH)2 D3 treatment may be useful in the alleviation of hepatic lesions by decreasing glycooxidant stress in both NAFLD and ALD models created by HFr- and EtOH-treated rats, respectively.

Low serum vitamin D level associated with incident advanced liver disease in the general population - a prospective study

BACKGROUND

Vitamin D deficiency is a common finding in chronic liver disease. It has also been linked to the pathogenesis of non-alcoholic fatty liver disease, hepatic fibrogenesis, decompensation and hepatocellular carcinoma.

AIMS

We analyzed whether serum vitamin D is associated with incident advanced liver disease in the general population.

METHODS

Serum 25-hydroxyvitamin D was measured in 13807 individuals participating in the Finnish population-based health examination surveys FINRISK 1997 and Health 2000. Data were linked with incident advanced liver disease (hospitalization, cancer or death related to liver disease). During a follow-up of 201444 person-years 148 severe liver events occurred. Analyses were performed using multivariable Cox regression analyses.

RESULTS

Vitamin D level associated with incident advanced liver disease with the hazard ratio of 0.972 (95% confidence interval 0.943-0.976, p < .001), when adjusted for age, sex, blood sampling season and stratified by cohort.The association remained robust and significant in multiple different adjustment models adjusting sequentially for 22 potential confounders.

CONCLUSION

Low vitamin D level is linked to incident advanced liver disease at population level.

Calcium Carbonate Attenuates Withdrawal and Reduces Craving: A Randomized Controlled Trial in Alcohol-Dependent Patients

INTRODUCTION

Preclinical studies have shown that calcium seems to be the active component of the anti-craving drug acamprosate (Ca2+ bis-acetyl-homotaurinate). Clinical effects in humans have also indicated an association between increased calcium plasma concentration due to acamprosate treatment and better outcome relating to time to relapse and cumulative abstinence. In contrast, low calcium concentration in alcohol-dependent patients was related with craving for alcohol. The main goal of the trial was to investigate whether an oral calcium administration is able to affect craving, withdrawal, and relapse risk in alcohol-dependent patients.

METHODS

We conducted a single-blind, randomized, monocentric, controlled clinical two-arm trial in alcohol-dependent patients (Clinical Trials Registration: DRKS00011293). A total of 55 alcohol-dependent subjects received calcium carbonate (800 mg + 5 μg vitamin D) versus sodium bicarbonate (1,000 mg) daily during the 14 days of inpatient alcohol-withdrawal treatment.

RESULTS

Based on an intention-to-treat protocol, withdrawal intensity (assessed with CIWA-Ar) in the calcium carbonate group attenuated faster than in the sodium bicarbonate subgroup. Alcohol craving (assessed with OCDS) in the calcium carbonate subgroup was also significantly reduced versus the sodium bicarbonate subgroup.

CONCLUSION

Our data support earlier findings and show that treatment with calcium carbonate during alcohol withdrawal reduces symptoms of alcohol withdrawal as well as alcohol craving in a controlled clinical pilot study. Mode of actions will need to be determined to allow the further development of pharmacological interventions beyond Ca2+ bis-acetyl-homotaurinate.

Calcitriol alleviates ethanol-induced hepatotoxicity via AMPK/mTOR-mediated autophagy

Excessive ethanol consumption causes cellular damage, leading to fetal alcohol syndrome and alcohol liver diseases, which are frequently seen with vitamin D (VD) deficiency. A great deal of progress has been achieved in the mechanisms of ethanol-induced hepatocyte damage. However, there are limited intervention means to reduce or rescue hepatocytes damage caused by ethanol. On the basis of our preliminary limited screen process, calcitriol showed a positive effect on protecting hepatocyte viability. Therefore, the molecular basis is worth elucidating. We found that calcitriol pretreatment markedly improved the cell viability, decreased cell apoptosis and oxidative stress and alleviated the abnormal mitochondrial morphology and membrane potential of hepatocytes induced by ethanol. Notably, autophagy was significantly enhanced by calcitriol, as evident by the increasing number of autophagosomes and autolysosomes, upregulated LC3B-Ⅱ and ATG5 levels, and promotion of p62 degradation. Furthermore, calcitriol pretreatment increased the colocalization of GFP-LC3-labeled autophagosomes with mitochondria, suggesting that calcitriol effectively promoted ethanol-induced mitophagy in hepatocytes. In addition, the inhibition of autophagy attenuated the protective and preventive effect of calcitriol. Furthermore, the effect of calcitriol on autophagy was regulated by AMPK/mTOR signaling, and signaling transduction was dependent on the Vitamin D receptor (VDR). In conclusion, calcitriol ameliorates ethanol-induced hepatocyte damage by enhancing autophagy. It may offer a convenient preventive and hepatoprotective mean for people on occasional social drink.

Cyanidin-3-O-β-glucoside inactivates NLRP3 inflammasome and alleviates alcoholic steatohepatitis via SirT1/NF-κB signaling pathway

Alcoholic liver disease (ALD) is a major cause of liver disease worldwide. In patients with ALD, an increased level of hepatic inflammasome components was observed, together with an increased circulating pro-inflammatory cytokines. Cyanidin-3-O-β-glucoside (Cy-3-G) is a bioactive compound belonging to the anthocyanin group, which widely exists in deep-colored fruits and vegetables. Consumption of Cy-3-G is associated with lower risks of non-alcoholic fatty liver disease (NAFLD), liver fibrosis, obesity, atherosclerosis, and inflammation. However, whether Cy-3-G has effects on inflammasome formation and activation thereby protects against alcohol-induced liver damage remain elusive. In this study, we identified that dietary provision of Cy-3-G remarkably attenuated liver damage caused by excess energy intake and alcohol consumption. Supplement with Cy-3-G mediated NAD⁺ homeostasis, which stimulated SirT1 activity, resulting in suppressed NF-κB acetylation. Interestingly, Cy-3-G treatment suppressed NF-κB acetylation when SirT1 action was blunted by selective antagonist, and subsequently suppressed NLRP3 inflammasome activation and proinflammatory cytokines release in hepatic cell lines. Our findings first demonstrate that Cy-3-G at a physiologically achievable dosage alleviates alcohol-induced hepatic inflammation via inactivation of NLRP3 inflammasome and deacetylation of NF-κB, suggesting a promising therapeutic approach to alleviate alcohol-induced liver damage.

ESPEN practical guideline: Clinical nutrition in liver disease

BACKGROUND

The Practical guideline is based on the current scientific ESPEN guideline on Clinical Nutrition in Liver Disease.

METHODS

It has been shortened and transformed into flow charts for easier use in clinical practice. The guideline is dedicated to all professionals including physicians, dieticians, nutritionists and nurses working with patients with chronic liver disease.

RESULTS

A total of 103 statements and recommendations are presented with short commentaries for the nutritional and metabolic management of patients with (i) acute liver failure, (ii) alcoholic steatohepatitis, (iii) non-alcoholic fatty liver disease, (iv) liver cirrhosis, and (v) liver surgery/transplantation. The disease-related recommendations are preceded by general recommendations on the diagnostics of nutritional status in liver patients and on liver complications associated with medical nutrition.

CONCLUSION

This practical guideline gives guidance to health care providers involved in the management of liver disease to offer optimal nutritional care.

Current understanding of the metabolism of micronutrients in chronic alcoholic liver disease

Alcoholic liver disease (ALD) remains an important health problem worldwide. Perturbation of micronutrients has been broadly reported to be a common characteristic in patients with ALD, given the fact that micronutrients often act as composition or coenzymes of many biochemical enzymes responsible for the inflammatory response, oxidative stress, and cell proliferation. Mapping the metabolic pattern and the function of these micronutrients is a prerequisite before targeted intervention can be delivered in clinical practice. Recent years have registered a significant improvement in our understanding of the role of micronutrients on the pathogenesis and progression of ALD. However, how and to what extent these micronutrients are involved in the pathophysiology of ALD remains largely unknown. In the current study, we provide a review of recent studies that investigated the imbalance of micronutrients in patients with ALD with a focus on zinc, iron, copper, magnesium, selenium, vitamin D and vitamin E, and determine how disturbances in micronutrients relates to the pathophysiology of ALD. Overall, zinc, selenium, vitamin D, and vitamin E uniformly exhibited a deficiency, and iron demonstrated an elevated trend. While for copper, both an elevation and deficiency were observed from existing literature. More importantly, we also highlight several challenges in terms of low sample size, study design discrepancies, sample heterogeneity across studies, and the use of machine learning approaches.

Vitamin D Deficiency Attenuates Acute Alcohol-Induced Hepatic Lipid Accumulation in Mice

Vitamin D deficiency has been frequently reported in chronic liver disease. However, its influence on hepatic lipid accumulation in alcoholic liver disease remains unclear. The present study investigated the effects of vitamin D deficiency on acute alcohol-induced hepatic lipid metabolism in mice. Mice were fed with vitamin D deficient diet, in which vitamin D was depleted for 12 weeks to establish an animal model of vitamin D deficiency. Some mice were administered a single gavage of alcohol (4 g/kg bodyweight) before they were euthanized. Results show that feeding mice with vitamin D deficient diet did not induce hepatic lipid accumulation. In contrast, vitamin D deficiency markedly reduced alcohol-induced triacylglycerol (TAG) content and prevented hepatic lipid accumulation. Moreover, vitamin D deficiency significantly attenuated alcohol-induced sterol-regulated element-binding protein (SREBP)-1c activation, which regulates genes for hepatic fatty acid (FA) and TAG synthesis, and the expression of its target genes fatty acid synthase (Fasn) and acetyl-coenzyme- A carboxylase (Acc). In addition, vitamin D deficiency alleviated alcohol-induced downregulation of hepatic nuclear peroxisome proliferator-activated receptor (PPAR)α, which governs FA transport and β-oxidation, and the expression of Carnitine palmitoyltransferase (Cpt)-1α, cytochrome P450, family 4, subfamily a, polypeptide (Cyp4a)10, and Cyp4a14, which are key enzymes for hepatic fatty acids β-oxidation and ω-oxidation. Taken together, these results suggest that vitamin D deficiency is not a direct risk factor for hepatic lipid accumulation. Vitamin D deficiency alleviates acute alcohol-induced hepatic lipid accumulation through inhibiting hepatic de novo fatty acid syntheses and promoting fatty acid β-oxidation and ω-oxidation.

Growing burden of alcoholic liver disease in China: A review

Explosive economic growth and increasing social openness in China over the last 30 years have significantly boosted alcohol consumption, and consequently, the incidence of alcoholic liver disease (ALD) in China has increased. Because the epidemiologic and clinical features of ALD in the Chinese population may differ from those of the Caucasian population, this review describes the epidemiology, pathogenesis, genetic polymorphisms, diagnosis, and treatment of ALD in the Chinese population. This updated knowledge of ALD in China provides information needed for a global understanding of ALD and may help in the development of useful strategies for reducing the global ALD burden.

ESPEN guideline on clinical nutrition in liver disease

This update of evidence-based guidelines (GL) aims to translate current evidence and expert opinion into recommendations for multidisciplinary teams responsible for the optimal nutritional and metabolic management of adult patients with liver disease. The GL was commissioned and financially supported by ESPEN. Members of the guideline group were selected by ESPEN. We searched for meta-analyses, systematic reviews and single clinical trials based on clinical questions according to the PICO format. The evidence was evaluated and used to develop clinical recommendations implementing the SIGN method. A total of 85 recommendations were made for the nutritional and metabolic management of patients with acute liver failure, severe alcoholic steatohepatitis, non-alcoholic fatty liver disease, liver cirrhosis, liver surgery and transplantation as well as nutrition associated liver injury distinct from fatty liver disease. The recommendations are preceded by statements covering current knowledge of the underlying pathophysiology and pathobiochemistry as well as pertinent methods for the assessment of nutritional status and body composition.

An Argument for Vitamin D, A, and Zinc Monitoring in Cirrhosis

Malnutrition is prevalent in cirrhosis. Vitamin and mineral deficiencies, including vitamin D, vitamin A, and zinc, are common and have been shown to correlate with survival. Our aim was to review the mechanisms of vitamin D, vitamin A, and zinc deficiencies in cirrhosis and the clinical assessment of affected patients, their outcomes based on the current literature, and management. This is a narrative review including the relevant literature for cirrhosis and vitamin D, vitamin A, and zinc deficiencies. Vitamin D deficiency has important effects in cirrhosis, regardless of the cause of chronic liver disease.These effects include associations with fibrosis and outcomes such as infections, hepatocellular carcinoma, and mortality. Vitamin A deficiency is associated with liver disease progression to cirrhosis and clinical decompensation, including occurrence of ascites or hepatic encephalopathy. Zinc deficiency can lead to hepatic encephalopathy and impaired immune function. Such deficiencies correlate with patient survival and disease severity. Caution should be applied when replacing vitamin D, vitamin A, and zinc to avoid toxicity. Identification and appropriate treatment of vitamin and mineral deficiencies in cirrhosis may reduce specific nutritional and cirrhosis-related adverse events. Routine monitoring of vitamin A, vitamin D and zinc levels in cirrhosis should be considered.

Severe Vitamin D Deficiency Is Not Associated with Liver Damage in Morbidly Obese Patients

BACKGROUND AND AIMS

A deficiency in vitamin D could be deleterious during chronic liver diseases. However, contradictory data have been published in patients with non-alcoholic fatty liver disease. The aim of the study was to compare the blood level of 25 hydroxy vitamin D (25-OH vitamin D) with the severity of liver lesions, in a large cohort of morbidly obese patients.

PATIENTS AND METHOD

Three hundred ninety-eight morbidly obese patients had a liver biopsy. The non-alcoholic steatohepatitis (NASH) Clinical Research Network Scoring System Definition and Scores were used. 25-OH vitamin D was evaluated with a Diasorin®Elisa Kit. Logistic regression analyses were performed to obtain predictive factors of the severity of liver histology.

RESULTS

20.6 % of patients had NASH. The stage of fibrosis was F0 12.9 %, F1 57.36 %, F2 25.32 %, F3 (bridging fibrosis) 3.88 %, and F4 (cirrhosis) 0.52 %. The 25-OH vitamin D level inversely correlated to the NAS (r = 0.12 and p = 0.01) and to steatosis (r = 0.14 and p = 0.007); however, it was not associated with the presence of NASH. The level of vitamin D was significantly lower in patients with significant fibrosis compared to those without (15.9 (11.1-23.5) vs 19.6 (13.7-24.7) ng/ml, p = 0.02). There was an inverse correlation between the severity of fibrosis and the values of 25-OH vitamin D (r = 0.12 and p = 0.01). In a logistic regression analysis, no parameters were independently associated with the severity of fibrosis except the presence of steatohepatitis (1.94 (1.13-3.35) p = 0.017).

CONCLUSION

Low levels of 25-OH vitamin D were not independently associated with liver damage in morbidly obese patients with non-alcoholic fatty liver diseases (NAFLD).

Dietary supplementation in patients with alcoholic liver disease: a review on current evidence

BACKGROUND

Alcoholic liver disease (ALD) is one of the main causes of liver disease worldwide. Although the pathogenesis of ALD has not yet been well elucidated, the oxidative metabolites of ethanol such as acetaldehyde and reactive oxygen species play a pivotal role in the clinical and pathological spectrum of the disease. This review summarizes the existing evidences on dietary supplements considered to have antioxidant, and/or anti-inflammatory properties, and their role in the management of ALD and the proposed mechanisms.

DATA SOURCES

The present study reviewed all studies published in PubMed, ScienceDirect and Scopus, from 1959 to 2015, indicating the role of different dietary supplementation in attenuation of many pathophysiological processes involved in development and progression of ALD. Full-texts of citations were used except for those that were published in languages other than English.

RESULTS

Significant progress has been made to understand the key events and molecular players for the onset and progression of ALD from both experimental and clinical studies; however, there is no successful treatment currently available. The present review discussed the role of a variety of dietary supplements (e.g. vitamin A, carotenoids, vitamins B3, C and E, in addition to antioxidants and anti-inflammatory agents) in treating ALD. It has been shown that supplementation with some carotenoids, vitamin B3, vitamin C, silymarin, curcumin, probiotics, zinc, S-adenosylmethionine and garlic may have potential beneficial effects in animal models of ALD; however, the number of clinical studies is very limited. In addition, supplementation should be accompanied with alcohol cessation.

CONCLUSIONS

Since oxidative stress and inflammation are involved in the pathogenesis of ALD, dietary supplements that can modulate these pathologies could be useful in the treatment of ALD. In addition to alcohol cessation, these supplements have shown beneficial effects on animal models of ALD. Clinical trials are needed to validate the beneficiary role of these supplements in patients with ALD.

Synergistic effect of vitamin D and low concentration of transforming growth factor beta 1, a potential role in dermal wound healing

Dermal wound healing, in which transforming growth factor beta 1 (TGFβ1) plays an important role, is a complex process. Previous studies suggest that vitamin D has a potential regulatory role in TGFβ1 induced activation in bone formation, and there is cross-talk between their signaling pathways, but research on their effects in other types of wound healing is limited. The authors therefore wanted to explore the role of vitamin D and its interaction with low concentration of TGFβ1 in dermal fibroblast-mediated wound healing through an in vitro study. Human dermal fibroblasts were treated with vitamin D, TGFβ1, both, or vehicle, and then the wound healing functions of dermal fibroblasts were measured. To further explore possible mechanisms explaining the synergistic effect of vitamin D and TGFβ1, targeted gene silencing of the vitamin D receptor was performed. Compared to either factor alone, treatment of fibroblasts with both vitamin D and low concentration of TGFβ1 increased gene expression of TGFβ1, connective tissue growth factor, and fibronectin 1, and enhanced fibroblast migration, myofibroblast formation, and collagen production. Vitamin D receptor gene silencing blocked this synergistic effect of vitamin D and TGFβ1 on both collagen production and myofibroblast differentiation. Thus a synergistic effect of vitamin D and low TGFβ1 concentration was found in dermal fibroblast-mediated wound healing in vitro. This study suggests that supplementation of vitamin D may be an important step to improve wound healing and regeneration in patients with a vitamin D deficiency.