Antioxidant supplements for liver diseases

Vitamin E for people with non-alcoholic fatty liver disease

RATIONALE

Non-alcoholic fatty liver disease (NAFLD), recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD), is the most common liver disease worldwide, affecting an estimated 3 in 10 people. The available treatment is far from optimal. Diet and lifestyle changes to promote weight loss and weight loss maintenance are the basic management of NAFLD, but these are difficult to achieve and maintain. Vitamin E has shown beneficial effects on oxidative stress, which plays a major role in the pathogenesis of NAFLD. However, there is uncertainty about the effects of vitamin E for people with NAFLD.

OBJECTIVES

To evaluate the beneficial and harmful effects of vitamin E alone, or vitamin E in combination with other vitamins or minerals, versus placebo or no intervention in people with NAFLD.

SEARCH METHODS

We used recommended Cochrane search methods. The latest search was performed on 2 February 2024.

ELIGIBILITY CRITERIA

We included randomised clinical trials that compared vitamin E alone, or in combination with other vitamins or minerals, at any dose, duration, and route of administration, versus placebo or no intervention, in people with NAFLD of any age, sex, or ethnic origin. We included participants with imaging techniques or histology-proven NAFLD and minimal alcohol intake, and participants with steatohepatitis who had liver biopsies.

OUTCOMES

Our critical outcomes were all-cause mortality, liver-related mortality, and serious adverse events. Our important outcomes were liver-related morbidity, health-related quality of life, non-serious adverse events, biochemical response, and imaging assessment of the degree of fatty liver.

RISK OF BIAS

We used Cochrane's RoB 2 tool to assess risk of bias for each of the predefined outcomes.

SYNTHESIS METHODS

We used standard Cochrane methods. We used GRADE to assess the certainty of evidence.

INCLUDED STUDIES

We included 16 randomised clinical trials involving 1066 paediatric and adult participants with NAFLD. Experimental groups received vitamin E alone (14 trials) or vitamin E in combination with vitamin C (2 trials). Control groups received placebo in 13 trials and no intervention in three trials. Daily dosages of oral vitamin E ranged from 298 international units (IU) to 1000 IU. Co-interventions were lifestyle and low-calorie diet interventions in 13 trials, ursodeoxycholic acid in one trial, unchanged diet and physical activity in one trial, and baseline treatments for type 2 diabetes in one trial. Nine trials had more than two intervention groups, but we used only the groups in which vitamin E alone or vitamin E in combination with vitamin C were compared with placebo or no intervention. In total, 7.9% (84/1066) of participants dropped out. Follow-up ranged from 2 months to 24 months.

SYNTHESIS OF RESULTS

Vitamin E versus placebo or no intervention The effects of vitamin E versus placebo or no intervention on all-cause mortality (risk ratio (RR) 3.45, 95% confidence interval (CI) 0.57 to 20.86; 3 trials, 351 participants; very low certainty evidence) and serious adverse events (RR 1.91, 95% CI 0.30 to 12.01; 2 trials, 283 participants; very low certainty evidence) are very uncertain. There were no data on liver-related mortality or liver-related morbidity. The effects of vitamin E versus placebo or no intervention on physical health-related quality of life (mean difference (MD) 0.74, 95% CI -0.52 to 2.01; 2 trials, 251 participants; higher scores indicate better quality of life; very low certainty evidence); psychosocial health-related quality of life (MD -0.57, 95% CI -4.11 to 2.97; 2 trials, 251 participants; higher scores indicate better quality of life; very low certainty evidence); and non-serious adverse events (RR 0.86, 95% CI 0.64 to 1.17; 2 trials, 283 participants; very low certainty evidence) are also very uncertain. There were no data on proportion of participants without a decrease in liver enzymes. Vitamin E likely slightly reduces serum alanine transaminase (ALT) (MD -9.29, 95% CI -13.69 to -4.89; 11 trials, 708 participants; moderate certainty evidence) and aspartate aminotransferase (AST) (MD -4.90, 95% CI -7.24 to -2.57; 11 trials, 695 participants; moderate certainty evidence) levels compared with placebo or no intervention. Vitamin E may slightly reduce serum alkaline phosphatase (ALP) levels (MD -5.21, 95% CI -9.88 to -0.54; 5 trials, 416 participants; very low certainty evidence), but the evidence is very uncertain. Vitamin E plus vitamin C versus placebo There were no data on all-cause mortality, liver-related mortality, serious adverse events, liver-related morbidity, health-related quality of life, and non-serious adverse events. The effects of vitamin E plus vitamin C on reducing serum ALT (MD -0.50, 95% CI -4.58 to 3.58; 2 trials, 133 participants; very low certainty evidence), AST (MD 0.09, 95% CI -3.39 to 3.57; 1 trial, 88 participants; very low certainty evidence), and gamma-glutamyl transferase (GGT) levels (MD 1.58, 95% CI -3.22 to 6.38; 1 trial, 88 participants; very low certainty evidence) are very uncertain. We identified three ongoing trials, and six trials are awaiting classification.

AUTHORS' CONCLUSIONS

Given the very low certainty evidence, we do not know if long-term treatment (18 months to 24 months) with vitamin E administered alone affects all-cause mortality, serious adverse events, quality of life, or non-serious adverse events in people with NAFLD when compared with placebo or no intervention. We found no data on liver-related mortality, liver-related morbidity, or proportion of participants without a decrease in liver enzymes. Vitamin E likely reduces ALT and AST slightly when compared with placebo, but whether this has any impact on the clinical course in people with NAFLD is unknown. The trials on vitamin E plus vitamin C did not report on all-cause mortality, liver-related mortality, serious adverse events, liver-related morbidity, health-related quality of life, or non-serious adverse events. Given the very low certainty evidence, we do not know the effects of vitamin E plus vitamin C on liver enzymes in people with NAFLD when compared with placebo.

FUNDING

Three trials disclosed no external funding. Five trials were industry funded. Five trials were funded by organisations with no vested interests. Three trials did not provide any information on clinical trial support or sponsorship.

REGISTRATION

Protocol: doi.org/10.1002/14651858.CD015033.

Metabolic Disorders in Patients with Chronic Hepatitis B Virus Infection: Coffee as a Panacea? (ANRS CO22 Hepather Cohort)

People living with chronic hepatitis B virus (HBV) infection are at high risk of liver disease progression, which is positively associated with metabolic disorders, but inversely associated with dyslipidemia. Diet, including dietary antioxidants, is a lever of metabolic disorder management. In particular, elevated coffee consumption is associated with different metabolic outcomes in the general population. We aimed to test whether such associations occur in HBV-infected people. Based on cross-sectional data from the ANRS CO22 Hepather cohort, we performed logistic regression models with (i) dyslipidemia, (ii) hypertension, and (iii) diabetes as outcomes, and with demographic, clinical, and socio-behavioral (including coffee consumption) data as explanatory variables. Among 4746 HBV-infected patients, drinking ≥3 cups of coffee per day was associated with a higher risk of dyslipidemia (adjusted odds ratio [95% confidence interval] 1.49 [1.10–2.00], p = 0.009) and a lower risk of hypertension (0.64 [0.50–0.82], p = 0.001). It was not associated with diabetes. Elevated coffee consumption was associated with a higher risk of dyslipidemia and a lower risk of hypertension in HBV-infected patients, two effects expected to be associated with favorable clinical outcomes. Further studies should test whether such metabolic benefits translate into reduced mortality risk in this population.

Case Report: Extended Clinical Spectrum of the Neonatal Diabetes With Congenital Hypothyroidism Syndrome

BACKGROUND

Neonatal diabetes with congenital hypothyroidism (NDH) syndrome is a rare condition caused by homozygous or compound heterozygous mutations in the GLI-similar 3 coding gene GLIS3. Almost 20 patients have been reported to date, with significant phenotypic variability.

CASE PRESENTATION

We describe a boy with a homozygous deletion (exons 5-9) in the GLIS3 gene, who presents novel clinical aspects not reported previously. In addition to neonatal diabetes, congenital hypothyroidism and other known multi-organ manifestations such as cholestasis and renal cysts, he suffered from hyporegenerative anemia during the first four months of life and presents megalocornea in the absence of elevated intraocular pressure. Compensation of partial exocrine pancreatic insufficiency and deficiencies in antioxidative vitamins seemed to have exerted marked beneficial impact on several disease symptoms including cholestasis and TSH resistance, although a causal relation is difficult to prove. Considering reports on persistent fetal hemoglobin detected in a few children with GLIS3 mutations, the transient anemia seen in our patient may represent a further symptom associated with either the GLIS3 defect itself or, secondarily, micronutrient deficiency related to exocrine pancreatic deficiency or cholestasis.

CONCLUSIONS

Our report expands the phenotypic spectrum of patients with GLIS3 mutations and adds important information on the clinical course, highlighting the possible beneficial effects of pancreatic enzyme and antioxidative vitamin substitutions on characteristic NDH syndrome manifestations such as TSH resistance and cholestasis. We recommend to carefully screen infants with GLIS3 mutations for subtle biochemical signs of partial exocrine pancreatic deficiency or to discuss exploratory administration of pancreatic enzymes and antioxidative vitamins, even in case of good weight gain and fecal elastase concentrations in the low-to-normal range.

Sulforaphane: Its "Coming of Age" as a Clinically Relevant Nutraceutical in the Prevention and Treatment of Chronic Disease

A growing awareness of the mechanisms by which phytochemicals can influence upstream endogenous cellular defence processes has led to intensified research into their potential relevance in the prevention and treatment of disease. Pharmaceutical medicine has historically looked to plants as sources of the starting materials for drug development; however, the focus of nutraceutical medicine is to retain the plant bioactive in as close to its native state as possible. As a consequence, the potency of a nutraceutical concentrate or an extract may be lower than required for significant gene expression. The molecular structure of bioactive phytochemicals to a large extent determines the molecule's bioavailability. Polyphenols are abundant in dietary phytochemicals, and extensive in vitro research has established many of the signalling mechanisms involved in favourably modulating human biochemical pathways. Such pathways are associated with core processes such as redox modulation and immune modulation for infection control and for downregulating the synthesis of inflammatory cytokines. Although the relationship between oxidative stress and chronic disease continues to be affirmed, direct-acting antioxidants such as vitamins A, C, and E, beta-carotene, and others have not yielded the expected preventive or therapeutic responses, even though several large meta-analyses have sought to evaluate the potential benefit of such supplements. Because polyphenols exhibit poor bioavailability, few of their impressive in vitro findings have been replicated in vivo. SFN, an aliphatic isothiocyanate, emerges as a phytochemical with comparatively high bioavailability. A number of clinical trials have demonstrated its ability to produce favourable outcomes in conditions for which there are few satisfactory pharmaceutical solutions, foreshadowing the potential for SFN as a clinically relevant nutraceutical. Although myrosinase-inert broccoli sprout extracts are widely available, there now exist myrosinase-active broccoli sprout supplements that yield sufficient SFN to match the doses used in clinical trials.

Poor chemical and microbiological quality of the commercial milk thistle-based dietary supplements may account for their reported unsatisfactory and non-reproducible clinical outcomes

Herbal-based dietary supplements have become increasingly popular. The extract from milk thistle (Silybum marianum), is often used for the treatment of liver diseases. However, serious concerns exist regarding the efficacy, composition, as well as the safety of these over-the-counter preparations. Therefore, the aim of the present study was to investigate the composition as well as chemical and biological safety of 26 milk thistle-based dietary supplements purchased from both the U.S. and Czech markets between 2016 and 2017. The study was focused on a determination of the composition of active ingredients, as well as analyses of possible contaminants including: mycotoxins, plant alkaloids, and pesticide residues, as well as the microbial purity. High-throughput analyses were performed using advanced U-HPLC-HRMS techniques. Large differences in the silymarin content were observed among individual milk thistle preparations, often in contrast with the information provided by the manufacturers. In addition, substantial inter-batch differences in silymarin content were also demonstrated. In all milk thistle preparations tested, large numbers and high concentrations of mycotoxins and several pesticides, as well as the substantial presence of microbiological contamination were detected, pointing to serious safety issues. In conclusion, our results strongly indicate the need for strict controls of the composition, chemical contaminants, as well as the microbiological purity of commercial milk thistle extracts used for the treatment of liver diseases. Poor definition of these preparations together with contamination by biologically active substances may not only account for the inconsistency of clinical observations, but also be responsible for possible herbal-based dietary supplements-induced liver injury.

p66Shc Contributes to Liver Fibrosis through the Regulation of Mitochondrial Reactive Oxygen Species

Background: p66Shc is a redox enzyme that mediates mitochondrial reactive oxygen species (ROS) generation. p66Shc inhibition confers protection against liver injury, however, its functional contribution to liver fibrosis remains unclear. The aim of this study is to explore the involvement of p66Shc in liver fibrosis and underlying mechanism of p66Shc by focusing on mitochondrial ROS. Methods: p66Shc-silenced mice were injected with carbon tetrachloride (CCl₄). Primary hepatic stellate cells (HSCs) were performed with p66Shc silencing or overexpression prior to TGF-β1 stimulation. Results: p66Shc expression was progressively elevated in mice with CCl₄-induced liver fibrosis, and p66Shc silencing in vivo significantly attenuated fibrosis development, reducing liver damage, oxidative stress and HSC activation, indicated by the decreased α-SMA, CTGF and TIMP1 levels. Furthermore, in primary HSCs, p66Shc-mediated mitochondrial ROS production played a vital role in mitochondrial morphology and cellular metabolism. Knockdown of p66Shc significantly inhibited mitochondrial ROS production and NOD-like receptor protein 3 (NLRP3) inflammasome activation, which were closely associated with HSC activation, indicated by the decreased α-SMA, CTGF and TIMP1 levels. However, p66Shc overexpression exerted the opposite effects, which were suppressed by a specific mitochondrial ROS scavenger (mito-TEMPO). More importantly, p66Shc expression was significantly increased in human with liver fibrosis, accompanied by NLRP3 inflammasome activation. Conclusions: p66Shc is a key regulator of liver fibrosis by mediating mitochondrial ROS production, which triggers NLRP3 inflammasome activation.

Review and gap analysis: molecular pathways leading to fetal alcohol spectrum disorders

Alcohol exposure during pregnancy affects the development of the fetus in various ways and may lead to Fetal Alcohol Spectrum Disorders (FASD). FASD is one of the leading preventable forms of neurodevelopmental disorders. In the light of prevention and early intervention, knowledge on how ethanol exposure induces fetal damage is urgently needed. Besides direct ethanol and acetaldehyde toxicity, alcohol increases oxidative stress, and subsequent general effects (e.g., epigenetic imprinting, gene expression, and metabolite levels). The current review provides an overview of the existing knowledge about specific downstream pathways for FASD that affects e.g., the SHH pathway, cholesterol homeostasis, neurotransmitter signaling, and effects on the cytoskeleton. Available human data vary greatly, while animal studies with controlled ethanol exposition are only to a certain limit transferable to humans. The main deficits in knowledge about FASD are the lack of pathophysiological understanding and dose-response relationships, together with the lack of reliable biomarkers for either FASD detection or estimation of susceptibility. In addition to single outcome experiments, omics data should be generated to overcome this problem. Therefore, for future studies we recommend holistic data driven analysis, which allows integrative analyses over multiple levels of genetic variation, transcriptomics and metabolomics data to investigate the whole image of FASD development and to provide insight in potential drug targets for intervention.

Dietary and metabolic modulators of hepatic immunity

The liver is the central metabolic organ of the organism and is thus constantly exposed to gut-derived dietary and microbial antigens. The liver maintains homoeostatic tolerance to these mostly harmless antigens. However, the liver also functions as a barrier organ to harmful pathogens and is thus permissive to liver inflammation. The regulation of the delicate balance between liver tolerance and liver inflammation is of vital importance for the organism. In recent years, a general role for dietary components and metabolites as immune mediators has been emerging. However, although the liver is exposed to a great deal of metabolic mediators, surprisingly, little is known about their actual role in the regulation of hepatic immune responses. Here, we will explore the possible impacts of metabolic mediators for homoeostatic and pathological immunity in the liver, by highlighting selected examples of metabolic immune regulation in the liver.

Behaviors of consumers, physicians and pharmacists in response to adverse events associated with dietary supplement use

Background

The prevalence of dietary supplements has increased in Japan, and, as a consequence, the adverse events associated with dietary supplement use have become more prominent. Severe adverse events must be reported to the Japanese government via public health centers. However, the number of cases reported to the Japanese government is limited. To clarify this discrepancy, we conducted an internet questionnaire, and surveyed how consumers, physicians and pharmacists acted when they or their patients developed adverse events due to dietary supplement use.

Methods

This study was completed by 2732 consumers, 515 physicians, and 515 pharmacist via internet surveillance on November 2015.

Results

Although 8.8% of consumers developed adverse events including diarrhea, constipation, stomachache, headache, and nausea and vomiting, most of them did not report their adverse events to public health centers. However, some consumers went to hospitals because of adverse events. We also surveyed how physicians and pharmacists acted when their patients developed adverse events due to dietary supplement use. Most physicians and pharmacists did not report these cases to public health centers because they were unable to definitively prove the cause-and-effect relationship of these adverse events. Furthermore, some physicians and pharmacists did not know how or where to report these adverse events.

Conclusions

We clarified the reasons for the limited number of reports of adverse events to the Japanese government in this survey. It is important to encourage not only consumers, but also physicians and pharmacists to report adverse events to public health centers. In addition, an analyzing tool of cause-and-effect relationships might be helpful for physicians and pharmacists.

Electronic supplementary material

The online version of this article (doi:10.1186/s12937-017-0239-4) contains supplementary material, which is available to authorized users.

Molecular pathogenesis and clinical consequences of iron overload in liver cirrhosis

BACKGROUND

The liver, as the main iron storage compartment and the place of hepcidin synthesis, is the central organ involved in maintaining iron homeostasis in the body. Excessive accumulation of iron is an important risk factor in liver disease progression to cirrhosis and hepatocellular carcinoma. Here, we review the literature on the molecular pathogenesis of iron overload and its clinical consequences in chronic liver diseases.

DATA SOURCES

PubMed was searched for English-language articles on molecular genesis of primary and secondary iron overload, as well as on their association with liver disease progression. We have also included literature on adjuvant therapeutic interventions aiming to alleviate detrimental effects of excessive body iron load in liver cirrhosis.

RESULTS

Excess of free, unbound iron induces oxidative stress, increases cell sensitivity to other detrimental factors, and can directly affect cellular signaling pathways, resulting in accelerated liver disease progression. Diagnosis of liver cirrhosis is, in turn, often associated with the identification of a pathological accumulation of iron, even in the absence of genetic background of hereditary hemochromatosis. Iron depletion and adjuvant therapy with antioxidants are shown to cause significant improvement of liver functions in patients with iron overload. Phlebotomy can have beneficial effects on liver histology in patients with excessive iron accumulation combined with compensated liver cirrhosis of different etiology.

CONCLUSION

Excessive accumulation of body iron in liver cirrhosis is an important predictor of liver failure and available data suggest that it can be considered as target for adjuvant therapy in this condition.

Acute Alcoholic Hepatitis: Therapy

Alcoholic hepatitis (AH) causes great morbidity and mortality in the United States and throughout the world. Advances in therapy have proven difficult. In part, this reflects challenges in diagnosis, including the distinction between AH and acute-on-chronic liver failure. Liver biopsy is the best method to clarify the cause in circumstances whereby conflicting clinical data confound the diagnosis. All treatment of AH begins with abstinence from alcohol. All patients with AH should be given sufficient nutrition. Prednisolone has become the principal agent for treating patients with severe AH.

Chemoprotective effect of omega-3 fatty acids on thioacetamide induced hepatic fibrosis in male rats

The current study was designed to investigate the possible protective effect of omega-3 fatty acids from fish oil on hepatic fibrosis induced by thioacetamide (TAA) in male rats. The experimental animals were divided into four groups. The first group was received saline solution and served as control. The second group was given 250 mg/kg body weight of TAA. The third group was treated with omega-3 fatty acids and TAA. The fourth group was given saline solution and supplemented with omega-3 fatty acids. Treatment of rats with TAA for three and six weeks resulted in a significant decrease in body weight gain, while the value of liver/body weight ratio was statistically increased. Furthermore, the levels of serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase and total bilirubin were significantly increased. After three weeks of exposure to only TAA, liver sections showed an abnormal morphology characterized by noticeable fibrosis with the extracellular matrix collagen contents and damage of liver cells’ structure. Liver sections from rats treated with only TAA for six weeks revealed an obvious increase in extracellular matrix collagen content and bridging fibrosis. Treating TAA-intoxicated rats with omega-3 fatty acids significantly attenuated the severe physiological and histopathological changes. Finally, the present investigation suggests that omega-3 fatty acids could act against hepatic fibrosis induced by TAA due to its antioxidant properties, thus supporting its use in hepatic fibrosis therapy.

Relationships among alcoholic liver disease, antioxidants, and antioxidant enzymes

Excessive consumption of alcoholic beverages is a serious cause of liver disease worldwide. The metabolism of ethanol generates reactive oxygen species, which play a significant role in the deterioration of alcoholic liver disease (ALD). Antioxidant phytochemicals, such as polyphenols, regulate the expression of ALD-associated proteins and peptides, namely, catalase, superoxide dismutase, glutathione, glutathione peroxidase, and glutathione reductase. These plant antioxidants have electrophilic activity and may induce antioxidant enzymes via the Kelch-like ECH-associated protein 1-NF-E2-related factor-2 pathway and antioxidant responsive elements. Furthermore, these antioxidants are reported to alleviate cell injury caused by oxidants or inflammatory cytokines. These phenomena are likely induced via the regulation of mitogen-activating protein kinase (MAPK) pathways by plant antioxidants, similar to preconditioning in ischemia-reperfusion models. Although the relationship between plant antioxidants and ALD has not been adequately investigated, plant antioxidants may be preventive for ALD because of their electrophilic and regulatory activities in the MAPK pathway.

Effect of hydrosoluble vitamin E on erythrocyte membrane lipid composition in patients with advanced cirrhosis: An open-label pilot trial

AIM

Deficiency in vitamin E, a natural antioxidant, participates in abnormal erythrocyte membrane lipids, structural alterations and hemolysis in advanced cirrhosis. Poor absorption of fat-soluble vitamins limits full correction of deficiency with standard formulations in cirrhosis with cholestasis. The aim of the present study was to examine safety and effects of tocofersolan, a water-soluble derivative of vitamin E, on erythrocyte membrane lipids and anemia in patients with biopsy-proven advanced cirrhosis, vitamin E deficiency and hemolysis.

METHODS

Twenty patients (age, 53 ± 10 years; Child class B/C, 8/12), with low plasma vitamin E, chronic anemia and hemolysis, received oral tocofersolan 700 mg/day for 4 weeks. Erythrocyte membrane lipid composition (cholesterol [Chol], phospholipids [Phosph]) was determined by enzymatic assays. Total and conjugated bilirubin, hemoglobin and vitamin E were measured.

RESULTS

Abdominal pain occurred in one patient. Five patients received blood transfusions due to severe anemia. After 4 weeks, both Chol and Phosph decreased, but changes were not significant. Both plasma vitamin E (P < 0.05) and hemoglobin (P < 0.05) increased, together with a decrease in total (P < 0.05) and conjugated (P < 0.05) bilirubin.

CONCLUSION

In patients with advanced cirrhosis, low vitamin E plasma levels and chronic anemia with hemolysis, oral tocofersolan was overall well tolerated, but did not affect erythrocyte membrane lipid composition.

Role of vitamins in gastrointestinal diseases

A tremendous amount of data from research was published over the past decades concerning the roles of different vitamins in various gastrointestinal diseases. For instance, most vitamins showed an inverse relationship with the risk of colorectal carcinoma as well as other malignancies like gastric and esophageal cancer in observational trials, however interventional trials failed to prove a clear beneficial preventive role. On the other hand, more solid evidence was obtained from high quality studies for a role of certain vitamins in specific entities. Examples for this include the therapeutic role of vitamin E in patients with non-alcoholic steatohepatitis, the additive role of vitamins B₁₂ and D to the standard therapy of chronic hepatitis C virus, the role of vitamin C in reducing the risk of gallstones, the positive outcome with vitamin B₁₂ in patients with aphthous stomatitis, and the beneficial effect of vitamin D and B₁ in patients with inflammatory bowel disease. Other potential uses are yet to be elaborated, like those on celiac disease, pancreatic cancer, pancreatitis, cholestasis and other potential fields. Data from several ongoing interventional trials are expected to add to the current knowledge over the coming few years. Given that vitamin supplementation is psychologically accepted by patients as a natural compound with relative safety and low cost, their use should be encouraged in the fields where positive data are available.

Concomitant use of dietary supplements and medicines in patients due to miscommunication with physicians in Japan

We previously reported that some patients used dietary supplements with their medication without consulting with physicians. Dietary supplements and medicines may interact with each other when used concomitantly, resulting in health problems. An Internet survey was conducted on 2109 people who concomitantly took dietary supplements and medicines in order to address dietary supplement usage in people who regularly take medicines in Japan. A total of 1508 patients (two admitted patients and 1506 ambulatory patients) and 601 non-patients, who were not consulting with physicians, participated in this study. Purpose for dietary supplement use was different among ages. Dietary supplements were used to treat diseases in 4.0% of non-patients and 11.9% of patients, while 10.8% of patients used dietary supplements to treat the same diseases as their medication. However, 70.3% of patients did not declare dietary supplement use to their physicians or pharmacists because they considered the concomitant use of dietary supplements and medicines to be safe. A total of 8.4% of all subjects realized the potential for adverse effects associated with dietary supplements. The incidence of adverse events was higher in patients who used dietary supplements to treat their disease. Communication between patients and physicians is important for avoiding the adverse effects associated with the concomitant use of dietary supplements and medicines.

Mitigation of carbon tetrachloride-induced hepatic injury by methylene blue, a repurposed drug, is mediated by dual inhibition of GSK3β downstream of PKA

BACKGROUND AND PURPOSE

Methylene blue (MB) has recently been considered for new therapeutic applications. In this study, we investigated whether MB has antioxidant and mitochondria-protecting effects and can prevent the development of toxicant-induced hepatitis. In addition, we explored the underlying basis of its effects.

EXPERIMENTAL APPROACH

Blood biochemistry and histopathology were assessed in mice injected with CCl4 (0.5 mL·kg(-1)) following MB administration (3 mg·kg(-1) ·day(-1), 3 days). Immunoblottings were performed to measure protein levels. Cell survival, H2 O2 , and mitochondrial superoxide and membrane permeability transition were determined in HepG2 cells.

KEY RESULTS

MB protected cells from oxidative stress induced by arachidonic acid plus iron; it restored GSH content and decreased the production of H2 O2 . It consistently attenuated mitochondria dysfunction, as indicated by inhibition of superoxide production and mitochondrial permeability transition. MB inhibited glycogen synthase kinase-3β (GSK3β) and protected the liver against CCl4. Using siRNA, the inhibition of GSK3β was shown to depend on AMPK. MB increased the activation of AMPK in vitro (3-24 h) and in vivo. MB also increased the phosphorylation of liver kinase B1 (LKB1) via cAMP-dependent PKA. SiRNA knockdown of LKB1 eliminated phosphorylation of AMPK and inhibited MB activation of AMPK. In addition, MB treatment (≤1 h) facilitated PKA-mediated GSK3β serine phosphorylation independently of AMPK.

CONCLUSIONS AND IMPLICATIONS

MB has antioxidant and mitochondria-protecting effects and protects the liver from toxicants, which results from the dual inhibition of GSK3β by AMPK downstream of PKA-activated LKB1, and PKA itself. Our findings reveal a novel pharmacological effect of MB and its molecular basis.

Inappropriate usage of dietary supplements in patients by miscommunication with physicians in Japan

Recently, people have used dietary supplements not only for nutritional supplementation, but also for treatment of their diseases. However, use of dietary supplements to treat diseases, especially with medications, may cause health problems in patients. In this study, we investigated use of dietary supplements in patients in Japan. This survey was conducted from January to December 2012, and was completed by 2732 people, including 599 admitted patients, 1154 ambulatory patients, and 979 healthy subjects who attended a seminar about dietary supplements. At the time of the questionnaire, 20.4% of admitted patients, 39.1% of ambulatory patients, and 30.7% of healthy subjects were using dietary supplements, which including vitamin/mineral supplements, herbal extracts, its ingredients, or food for specified health uses. The primary purpose for use in all groups was health maintenance, whereas 3.7% of healthy subjects, 10.0% of ambulatory patients, and 13.2% of admitted patients used dietary supplements to treat diseases. In addition, 17.7% of admitted patients and 36.8% of ambulatory patients were using dietary supplements concomitantly with their medications. However, among both admitted patients and ambulatory patients, almost 70% did not mention dietary supplement use to their physicians. Overall, 3.3% of all subjects realized adverse effects associated with dietary supplements. Communication between patients and physicians is important to avoid health problems associated with the use of dietary supplements.

Effects of α-tocopherol and β-carotene supplementation on liver cancer incidence and chronic liver disease mortality in the ATBC study

Background:

Recent data suggest the possible benefits of α-tocopherol and β-carotene supplementation on liver cancer and chronic liver disease (CLD), but the long-term trial data are limited.

Methods:

We evaluated the efficacy of supplemental 50 mg day⁻¹α-tocopherol and 20 mg day⁻¹β-carotene on incident liver cancer and CLD mortality in a randomised trial of 29 105 Finnish male smokers, who received supplementation for 5–8 years and were followed for 16 additional years for outcomes.

Results:

Supplemental α-tocopherol, β-carotene, or both, relative to placebo, did not reduce the risk of liver cancer or CLD, either overall, during the intervention or during the post-intervention period.

Conclusions:

Long-term supplemental α-tocopherol or β-carotene had no effect on liver cancer or CLD mortality over 24 years of follow-up.

Association of serum α-tocopherol, β-carotene, and retinol with liver cancer incidence and chronic liver disease mortality

BACKGROUND

Micronutrients may influence the development or progression of liver cancer and liver disease. We evaluated the association of serum α-tocopherol, β-carotene, and retinol with incident liver cancer and chronic liver disease (CLD) mortality in a prospective cohort of middle-aged Finnish male smokers.

METHODS

Baseline and 3-year follow-up serum were available from 29,046 and 22,805 men, respectively. After 24 years of follow-up, 208 men were diagnosed with liver cancer and 237 died from CLD. Hazards ratios and 95% confidence intervals were calculated for highest vs lowest quartiles from multivariate proportional hazards models.

RESULTS

Higher β-carotene and retinol levels were associated with less liver cancer (β-carotene: 0.35, 0.22-0.55, P-trend <0.0001; retinol: 0.58, 0.39-0.85, P-trend=0.0009) and CLD mortality (β-carotene: 0.47, 0.30-0.75, P-trend=0.001; retinol: 0.55, 0.38-0.78, P-trend=0.0007). α-Tocopherol was associated with CLD mortality (0.63, 0.40-0.99, P-trend=0.06), but not with liver cancer (1.06, 0.64-1.74, P-trend=0.77). Participants with higher levels of β-carotene and retinol, but not α-tocopherol, at both baseline and year 3 had lower risk of each outcome than those with lower levels.

CONCLUSIONS

Our findings suggest that higher concentrations of β-carotene and retinol are associated with incident liver cancer and CLD. However, such data do not indicate that supplementation should be considered for these diseases.

Glutathione redox control of asthma: from molecular mechanisms to therapeutic opportunities

Asthma is a chronic inflammatory disorder of the airways associated with airway hyper-responsiveness and airflow limitation in response to specific triggers. Whereas inflammation is important for tissue regeneration and wound healing, the profound and sustained inflammatory response associated with asthma may result in airway remodeling that involves smooth muscle hypertrophy, epithelial goblet-cell hyperplasia, and permanent deposition of airway extracellular matrix proteins. Although the specific mechanisms responsible for asthma are still being unraveled, free radicals such as reactive oxygen species and reactive nitrogen species are important mediators of airway tissue damage that are increased in subjects with asthma. There is also a growing body of literature implicating disturbances in oxidation/reduction (redox) reactions and impaired antioxidant defenses as a risk factor for asthma development and asthma severity. Ultimately, these redox-related perturbations result in a vicious cycle of airway inflammation and injury that is not always amenable to current asthma therapy, particularly in cases of severe asthma. This review will discuss disruptions of redox signaling and control in asthma with a focus on the thiol, glutathione, and reduced (thiol) form (GSH). First, GSH synthesis, GSH distribution, and GSH function and homeostasis are discussed. We then review the literature related to GSH redox balance in health and asthma, with an emphasis on human studies. Finally, therapeutic opportunities to restore the GSH redox balance in subjects with asthma are discussed.