Selenium in chronic liver disease

Selenium intake in relation to all-cause and cardiovascular mortality in individuals with nonalcoholic fatty liver disease: A nationwide study in nutrition

AIMS

Limited evidence exists regarding the association of selenium with risk of death in individuals with nonalcoholic fatty liver disease (NAFLD). This study was designed to investigate the relationship between dietary selenium intake with mortality in a nationally representative sample of United States adults with NAFLD.

METHODS

Dietary selenium intake was assessed in 2274 NAFLD adults younger than 60 years of age from the National Health and Nutrition Examination Survey (NHANES) III through a 24-hour dietary recall. NAFLD was diagnosed by liver ultrasound after excluding liver disease due to other causes. Cox proportional hazards models were utilized to assess the effect of dietary selenium intake on all-cause and cardiovascular mortality among individuals with NAFLD.

RESULTS

At a median follow-up of 27.4 years, 577 deaths occurred in individuals with NAFLD, including 152 cardiovascular deaths. The U-shaped associations were discovered between selenium intake with all-cause (Pnolinear = 0.008) and cardiovascular mortality (Pnolinear < 0.001) in adults with NAFLD after multivariate adjustment, with the lowest risk around selenium intake of 121.7 or 125.9 μg/day, respectively. Selenium intake in the range of 104.1-142.4 μg/day was associated with a reduced risk of all-cause mortality and, otherwise, an increased risk. Selenium intake in the range of 104.1-150.6 μg/day was associated with a reduced risk of cardiovascular death and, otherwise, an increased risk.

CONCLUSIONS

Both high and low selenium intake increased the risk of all-cause and cardiovascular death in adults younger than 60 years of age with NAFLD, which may help guide dietary adjustments and improve outcomes in adults with NAFLD.

Selenium prevented renal tissue damage in lipopolysaccharide-treated rats

OBJECTIVES

Kidney diseases are one of the common diseases, which are one of the main causes of death in society and impose costs on the health system of the society. A growing body of evidence has well documented that inflammatory responses and oxidative damage play a significant role in the progress of various kidney diseases.

METHODS

This study examined whether selenium (Sel) could prevent the detrimental influences of lipopolysaccharide (LPS) in rats. Four groups of Wistar rats were considered: control, LPS (1 mg/kg, i.p., for 14 days), LPS-Sel 1 (0.1 mg/kg, i.p., for 14 days), and LPS-Sel 2 (0.2 mg/kg, i.p., for 14 days).

RESULTS

Sel treatment markedly attenuated oxidative stress damage in the kidney tissue in LPS-induced renal toxicity. Generally, the administration of Sel resulted in improved antioxidant indicators such as catalase (CAT) and superoxide dismutase (SOD) activities, or total thiol content, and decreased malondialdehyde (MDA) in the kidney tissue. It also decreased interleukin-6 in kidney homogenates. Furthermore, Se treatment significantly inhibited the elevation of serum biochemical markers of kidney function including serum, BUN, and creatinine.

CONCLUSIONS

Based on the findings of the current study, it seems that the administration of Sel to LPS-treated rats improves renal function by reducing oxidative damage and inflammation in kidney tissue. However, more research is needed to reveal the accurate mechanisms for the effect of Sel on renal outcomes of LPS in human subjects.

Selenium deficiency caused hepatitis in chickens via the miR-138-5p/SelM/ROS/Ca2+ overload pathway induced by hepatocyte necroptosis

Selenoprotein M (SelM), a key thioredoxin like enzyme in the endoplasmic reticulum (ER), is closely related to hepatocyte degeneration. However, the role of miR-138-5p/SelM and necroptosis in chicken SelM-deficient hepatitis and the specific biological mechanism of liver inflammation caused by SelM deficiency have not been elucidated. We established an in vivo chicken liver Se deficiency model by feeding a low-Se diet. The miR-138-5p knockdown and overexpression models and SelM knockdown models were established in LMH cells for an in vitro study. Transmission electron microscopy, H&E staining, Fluo4-AM/ER staining, and flow cytometry were used to detect the morphological changes in chicken liver tissue and the expression changes of necroptosis and inflammation in chicken liver cells. We observed that Se deficiency resulted in liver inflammation, up-regulation of miR-138-5p expression and down-regulation of SelM expression in chickens. Oxidative stress, Ca2+ overload, energy metabolism disorder and necroptosis occurred in chicken liver tissue. Importantly, ROS and the Ca2+ inhibitor could effectively alleviate the energy metabolism disorder, necroptosis and inflammatory cytokine secretion caused by miR-138-5p overexpression and SelM knockdown in LMH cells. In conclusion, selenium deficiency causes hepatitis by upregulating miR-138-5p targeting SelM. Our research findings enrich our knowledge about the biological functions of SelM and provide a theoretical basis for the lack of SelM leading to liver inflammation in chickens.

Effect of Selenium Deficiency on the Development of Overt Hepatic Encephalopathy in Patients with Chronic Liver Disease

Selenium is an essential trace element to maintain good health. This retrospective study investigated the prevalence of selenium deficiency and its effect on overt hepatic encephalopathy (OHE) in patients with chronic liver disease (CLD). Patients who underwent serum selenium level measurement between January 2021 and April 2022 were enrolled. The factors associated with selenium deficiency (≤10 µg/dL) and the association between selenium deficiency and OHE were analyzed. Among 98 eligible patients, 24% were observed to have selenium deficiency, with a median serum selenium level of 11.8 µg/dL. The serum selenium levels were significantly lower in patients with cirrhosis than in those with chronic hepatitis (10.9 µg/dL vs. 12.4 µg/dL; p = 0.03). The serum selenium levels were negatively correlated with mac-2 binding protein glycan isomer, the FIB-4 index, albumin-bilirubin (ALBI) score, and Child-Pugh score. The ALBI score remained significantly associated with selenium deficiency (odds ratio, 3.23; 95% confidence interval [CI], 1.56-6.67). During a median follow-up period of 2.9 months, nine patients experienced OHE. Selenium deficiency was associated with OHE (hazard ratio, 12.75; 95% CI, 2.54-70.22). Selenium deficiency is highly prevalent in patients with CLD and is associated with an increased risk of OHE development.

Higher serum selenium concentration is associated with lower risk of all-cause and cardiovascular mortality among individuals with chronic kidney disease: A population-based cohort study of NHANES

Background

Selenium is an essential nutrient and trace element required for human health and plays an important role in antioxidative and anti-inflammatory processes. However, the long-term impact of selenium levels on the health of patients with chronic kidney disease remains unclear.

Method

Participants in this study were 3,063 CKD adults from the Third National Health and Nutrition Examination Survey (NHANES 1999–2000, 2003–2004, and 2011–2018). The mortality status and the cause of death of the study participants were obtained from the National Death Index records. For all-cause and cardiovascular disease (CVD) mortality, the models employed to estimate hazard ratios (HRs) and 95% CI were Cox proportional hazard models and competing risk models, respectively.

Result

During the follow-up period, 884 deaths occurred, including 336 heart-disease-associated deaths. The median (IQR) concentration of serum selenium was 181.7 (156.1, 201.5) μg/L. After full adjustment, serum selenium levels were associated with a decreased risk of mortality in patients with CKD, including all-cause and CVD mortality (P &lt; 0.001). The multivariate-adjusted HRs (95%CI) were 0.684 (0.549–0.852) for all-cause mortality (Ptrend &lt; 0.001) and 0.513 (0.356–0.739) for CVD mortality (Ptrend &lt; 0.001) when selenium concentrations were compared according to the extreme quartiles. Selenium levels are inversely associated with an increased risk of all-cause mortality and CVD mortality. Similar results were observed in subgroup and sensitivity analyses.

Conclusion

Higher serum selenium concentration was independently associated with a decreased risk of all-cause and CVD mortality in patients with CKD.

Antioxidant effects of Se-glutathione peroxidase in alcoholic liver disease

Oxidative damage induced by ethanol and its metabolites is one of the factors that fuels the development of alcoholic liver disease (ALD). Selenium (Se) is an effective cofactor for glutathione peroxidase (GPx), and has antioxidant effects that improve ALD. In patients with ALD, ethanol-induced oxidative damage inhibits the synthesis of related Se-containing proteins such as: selenoprotein P (Sepp1), albumin (ALB), and GPx in the liver, thus decreasing the overall Se level in patients. Both Se deficiency and excess can affect the expression of GPx, resulting in damage to the antioxidant defense system. This damage enhances oxidative stress by increasing the levels of reactive oxygen species (ROS) in the body, which aggravates the inflammatory response, lipid metabolism disorder, and lipid peroxidation and worsens ALD symptoms. A cascade of oxidative damages caused by ALD will deplete selenium deposition in the body, stimulate the expression of Gpx1, Sepp1, and Gpx4, and thus mobilize systemic selenoproteins, which can restore GPx activity in the hepatocytes of ALD patients, reduce the levels of reactive oxygen species and alleviate oxidative stress, the inflammatory response, lipid metabolism disorder, and lipid peroxidation, thus helping to mitigate ALD. This review provides a reference for future ALD studies that evaluate the regulation of Se levels and contributes to studies on the potential pathological mechanisms of Se imbalance in ALD.

Tissue Heavy Metals in Liver Diseases

BACKGROUND

Our objective was to determine the levels of heavy metals, oxidants, and antioxidants in liver tissue of patients with chronic liver disease (CLD) compared with healthy living liver donors (LLDs).

METHODS

We obtained liver specimens from patients undergoing liver transplant for CLD. Samples were also obtained from LLDs. Biochemical analyses were performed on all samples, and the levels of liver tissue, heavy metal, and oxidant-antioxidants biomarker levels in patients with CLD were compared with those measured in LLDs.

RESULTS

One hundred and eighteen individuals were included for analyses. Fifty-nine were patients with CLD, and 59 were LLDs. The median levels of liver tissue of superoxide dismutase (P = .009), glutathione peroxidase (P = .042), total oxidant status (P = .006), oxidative stress index (P < .001), and copper (P = .035) were prominently more elevated in CLD than LLDs. On the other hand, the median levels of liver tissue of cadmium (P < .001), selenium (P = .042), and zinc (P < .001) levels were more elevated in the LLDs than patients with CLD. The 2 groups were similar in terms of total antioxidant status, manganese, arsenic, and lead levels.

CONCLUSIONS

Superoxide accumulation in the liver was higher in patients with CLD. Concerning heavy metals, only the median tissue copper was elevated in patients with CLD with higher Cu/Zn ratio. Cadmium, selenium, and zinc were significantly higher in the healthy LLDs.

Protective effects of epigallocatechin-3-o-gallate combined with organic selenium against transforming growth factor-beta 1-induced fibrosis in LX-2 cells

In this study, we investigated the protective effects and possible mechanism of epigallocatechin-3-o-gallate (EGCG) combined with organic selenium in transforming growth factor (TGF)-β1-activated LX-2 cells. After 12 h of starvation, LX-2 cells were treated with 10 ng/ml of recombinant TGF-β1 and different concentrations of EGCG, L-selenomethionine (L-SeMet), or L-selenomethylcysteine (L-SeMC) for 24 h. We found that 100 and 200 μM EGCG combined with 1 mM L-SeMet or L-SeMC showed a synergistic effect in decreasing the survival rate of activated LX-2 cells. In addition, the combination of 100 mM EGCG and 1 mM L-SeMet or L-SeMC promoted the apoptosis of activated LX-2 cells. Compared with the EGCG treatment group, the combination intervention group had significantly suppressed levels of hepatic stellate cell activation markers including alpha-smooth muscle actin, collagen type I alpha 1, collagen type III alpha 1, 5-hydroxytryptophan (5-HT), and 5-HT receptors 2A and 2B. Moreover, interleukin-10 levels were decreased, while TGF-β1 levels were increased after TGF-β1 activation in LX-2 culture medium, whereas the combin1ation intervention reversed this phenomenon. The combination treatment had a more pronounced effect than any single treatment at the same dose. These results demonstrated that the combination of EGCG and organic selenium synergistically improves the TGF-β1-induced fibrosis of LX-2 cells to some extent by promoting apoptosis and inhibiting cell activation. PRACTICAL APPLICATIONS: Here, we found that the effects of epigallocatechin-3-o-gallate (EGCG) + L-selenomethionine or L-selenomethylcysteine were more pronounced than those of EGCG alone. Future studies should investigate the protective effects of green tea and selenium-enriched green tea against hepatic fibrosis and explore the differences in their molecular mechanisms. The results of this study will be helpful for the development and utilization of selenium-enriched tea for food processing and health supplement production.

The Role and Mechanisms of Selenium Supplementation on Fatty Liver-Associated Disorder

Non-alcoholic fatty liver disease (NAFLD) is the most frequent chronic liver disease without effective therapy. Selenium, as an essential trace element for humans, is notable for its antioxidant properties. The previous study shows that selenium levels in NAFLD patients are lower than normal ones. Selenium supplementation can effectively alleviate metabolic disorders by relieving anti-oxidative stress and anti-inflammatory regulation. However, the correlation between selenium and NAFLD has not been fully clarified. Herein, we review the current studies on selenium in regulating the different stages of NAFLD and summarize relevant clinical trials to highlight the potential roles of selenium in NAFLD treatment.

Protective Effect of Selenium-Enriched Green Tea on Carbon Tetrachloride-Induced Liver Fibrosis

The major pathogenic feature of liver fibrosis is that oxidative stress motivation of hepatic stellate cells (HSCs) alters the balance between the synthesis and degradation of extracellular matrix (ECM) and HSCs into proliferative myofibroblasts. Green tea and selenium (Se) can protect the liver from damage; however, the precise mechanism of green tea and the action of Se in green tea on hepatic fibrosis remain unclear. Several studies have demonstrated the profibrogenic role of 5-hydroxytryptamine (5-HT) and 5-hydroxytryptamine receptor (5-HTR) 2A/2B in the liver. The current study aimed to investigate the protective effects and possible mechanisms of selenium-enriched green tea on carbon tetrachloride (CCl₄)-induced liver fibrosis in male C57BL/6 J mice. After a 4-week intervention with tea solution, histological analysis of the liver showed that green tea interventions alleviated hepatic fibrosis, which was supported by the changes in collagen type I, collagen type III, and α-smooth muscle actin in the liver. Tea interventions significantly inhibited the CCl₄-provoked increase of duodenal 5-HT and tryptophan hydroxylase and hepatic 5-HT and 5-HTR2A/2B levels. All of them were lower in the selenium-enriched green tea group than in regular green tea group. Se-enriched green tea had a more pronounced improvement in liver ECM deposition and scar formation and peripheral 5-HT signals than regular green tea. Thus, green tea, especially those enriched with selenium, can improve liver fibrosis through intestinal 5-HT-hepatic 5-HTR signaling.

Selenium Status in Patients with Chronic Liver Disease: A Systematic Review and Meta-Analysis

Background: The potential role of selenium in preventing chronic liver diseases remains controversial. This meta-analysis aimed to summarize the available evidence from observational studies and intervention trials that had evaluated the associations between body selenium status and chronic liver diseases. Methods: We comprehensively searched MEDLINE, Embase, Web of Science, and Cochrane Library from inception to April 2021. The study protocol was registered at PROSPERO (CRD42020210144). Relative risks (RR) for the highest versus the lowest level of selenium and standard mean differences (SMD) with 95% confidence intervals (CI) were pooled using random-effects models. Heterogeneity and publication bias were evaluated using the I² statistic and Egger’s regression test, respectively. Results: There were 50 studies with 9875 cases and 12975 population controls in the final analysis. Patients with hepatitis (SMD = −1.78, 95% CI: −2.22 to −1.34), liver cirrhosis (SMD = −2.06, 95% CI: −2.48 to −1.63), and liver cancer (SMD = −2.71, 95% CI: −3.31 to −2.11) had significantly lower selenium levels than controls, whereas there was no significant difference in patients with fatty liver diseases (SMD = 1.06, 95% CI: −1.78 to 3.89). Moreover, the meta-analysis showed that a higher selenium level was significantly associated with a 41% decrease in the incidence of significant advanced chronic liver diseases (RR = 0.59, 95% CI: 0.49 to 0.72). Conclusion: Our meta-analysis suggested that both body selenium status and selenium intake were negatively associated with hepatitis, cirrhosis, and liver cancer. However, the associations for fatty liver diseases were conflicting and need to be established in prospective trials.

Increased serum selenium levels are associated with reduced risk of advanced liver fibrosis and all-cause mortality in NAFLD patients: National Health and Nutrition Examination Survey (NHANES) III

INTRODUCTION AND OBJECTIVES

Selenium supplementation has been shown to have therapeutic value in chronic liver disease. We aimed to investigate the association between serum selenium, severity of liver fibrosis, and mortality in patients with Nonalcoholic Fatty Liver Disease (NAFLD).

PATIENTS OR MATERIAL AND METHODS

A total of 33,944 patients were identified from the Third National Health and Nutrition Examination Survey. NAFLD was diagnosed by hepatic ultrasound after the exclusion of other forms of liver diseases. The severity of liver fibrosis was determined by NAFLD Fibrosis Score >0.676. Multivariate logistic regression analysis was used to investigate the relationship between serum selenium level and liver fibrosis. Association between serum selenium and all-cause mortality in NAFLD patients was also evaluated.

RESULTS

Multivariate logistic regression analysis demonstrated odds ratio of advanced liver fibrosis (NFS > 0.676) was significantly reduced with increasing serum selenium levels; OR 0.55, [95% CI 0.32-0.94] in the highest selenium quartile. On stratification analysis, the following populations had a significantly reduced risk of advanced liver fibrosis: non-Hispanic white = OR 0.41 [0.24,0.68]; female = OR 0.32 [0.15-0.66] and age >47 = OR 0.47 [0.28-0.79]. The relationship was significant regardless of BMI as noted by BMI ≤ 30 Kg/m2= OR 0.42 [0.19-0.91] and BMI > 30 Kg/m2=OR 0.52 [0.28-0.97]. Hazard ratio for all-cause mortality was HR 0.72 [0.56-0.95].

CONCLUSIONS

The risk of advanced liver fibrosis is inversely associated with serum selenium levels, particularly in older patients, Caucasians, and females. All-cause mortality decreased with increased selenium levels. Selenium may play a role in the prevention of liver fibrosis in NAFLD.

Hepatoprotective Effects of Selenium-Enriched Probiotics Supplementation on Heat-Stressed Wistar Rat Through Anti-Inflammatory and Antioxidant Effects

The purpose of this study was to elucidate the effects of selenium-enriched probiotics on the liver of heat-stressed Wistar rats. Ten-week-old male rats were assigned to four groups: control (Con); high temperature (HT); high temperature plus probiotics (HT + P: 10¹¹ CFU/mL Lactobacillus acidophilus and 10⁹ CFU/mL Saccharomyces cerevisiae); or high temperature plus selenium-enriched probiotics (HT + SeP: 0.3 mg/kg Se, 10¹¹ CFU/mL L. acidophilus and 10⁹ CFU/mL S. cerevisiae). The HT, HT + P, and HT + SeP groups were maintained at higher ambient temperature (40-42 °C), while the control group was kept at room temperature (25 °C). After 42 days of thermal exposure, blood and liver tissues were collected and analyzed for morphological and molecular markers of liver physiology. The body weight of rats in the HT group decreased but liver weight and live index were increased. Histological examination showed dilation of liver sinusoids and congestion of interstitial veins in HT group. Moreover, the histomorphology of the liver in HT + P and HT + SeP groups was restored, and the serum AST, ALT, ALP, LDH, and hepatic MDA level decreased significantly, but the serum total protein level and the liver SOD, T-AOC, and GSH-PX activities were increased significantly relative to the HT group. In addition, the mRNA level of Gpx1, SOD1, Nrf2, and Bcl-2 was significantly increased, while the expression level of Bax, IL-6, TNF-α, COX-2, NF-κB, α-SMA, TGFβ1, Collagen I, HSP70, and HSP90 was significantly decreased in liver tissues after SeP supplementation. We concluded that SeP can protect Wistar rats from oxidative stress, inflammation, apoptosis, and liver fibrosis induced by heat stress.

Current Trends of Essential Trace Elements in Patients with Chronic Liver Diseases

Essential trace elements play crucial roles in the maintenance of health, since they are involved in many metabolic pathways. A deficiency or an excess of some trace elements, including zinc, selenium, iron, and copper, frequently causes these metabolic disorders such as impaired glucose tolerance and dyslipidemia. The liver largely regulates most of the metabolism of trace elements, and accordingly, an impairment of liver functions can result in numerous metabolic disorders. The administration or depletion of these trace elements can improve such metabolic disorders and liver dysfunction. Recent advances in molecular biological techniques have helped to elucidate the putative mechanisms by which liver disorders evoke metabolic abnormalities that are due to deficiencies or excesses of these trace elements. A genome-wide association study revealed that a genetic polymorphism affected the metabolism of a specific trace element. Gut dysbiosis was also responsible for impairment of the metabolism of a trace element. This review focuses on the current trends of four trace elements in chronic liver diseases, including chronic hepatitis, liver cirrhosis, nonalcoholic fatty liver disease, and autoimmune liver diseases. The novel mechanisms by which the trace elements participated in the pathogenesis of the chronic liver diseases are also mentioned.

Selenium-enriched Bifidobacterium longum protected alcohol and high fat diet induced hepatic injury in mice

The objective of this study was to verify the protective effect of Bifidobacterium longum (BL) and the synergistical effect of Selenium and BL on alcohol plus high fat diet (HFD) induced hepatic injury in mice. We also want to explore the mechanism of Selenium-enriched Bifidobacterium longum (SeBL). C57BL/6 mice were treated with alcohol plus HFD with or without different dosage of BL or SeBL for 4 weeks. Serum levels of ALT, AST, TC, TG, LDL-C, HDL-C, FFAs, TNF-α, IL-6 and IL-1β, hepatic MDA level, SOD activity, the mRNA levels of AMPK, PPAR-α and SREBP1 were invested. SeBL inhibited lipid accumulation in hepatocytes; reduced serum AST and ALT levels; improved dyslipidemia; decreased serum FFAs, TC, TG and LDL-C levels. SeBL also inhibited alcohol plus HFD-induced hepatocyte oxidative stress through decrease in hepatic MDA levels and increase in SOD activity. SeBL also regulated lipid metabolism related genes such as AMPK, PPAR-α and SREBP1. Although BL had similar effect as SeBL, SeBL is more effective than BL. SeBL protected mice from alcohol plus HFD-induced hepatic injury in mice because of its inhibitory effect on hepatocellular oxidative stress, lipogenesis and inflammation. Selenium enhanced the protective effect of BL.

Selenium and selenoprotein P in nonalcoholic fatty liver disease

Conflicting data link nonalcoholic fatty liver disease (NAFLD), a disease with no currently approved treatment, with selenium (Se) and selenoprotein P (SELENOP), a glycoprotein synthesized and primarily secreted by the hepatocytes, functioning as a Se transporter from the liver to other tissues. This review aims to summarize the evidence between Se, SELENOP, and NAFLD, which may hopefully clarify whether current data on Se and SELENOP in NAFLD warrant further investigation for their diagnostic and therapeutic potential. Most, albeit not all, experimental data show a favorable effect of Se on hepatic steatosis, inflammation, and fibrosis. It seems that Se may exert an antioxidant effect on the liver, at least partly via increasing the activity of glutathione peroxidase, whose depletion contributes to the pathogenesis of hepatic inflammation and fibrosis. Se may also affect metalloproteinases, cytokines, and growth factors participating in the pathogenesis of NAFLD and, most importantly, may induce the apoptosis of hepatic stellate cells, the key players in hepatic fibrosis. However, the association between Se or SELENOP and insulin resistance, which is a principal pathogenetic factor of NAFLD, remains inconclusive. Clinical studies on Se or SELENOP in NAFLD are conflicting, apart from those in advanced liver disease (cirrhosis or hepatocellular carcinoma), in which lower circulating Se and SELENOP are constant findings. Existing data warrant further mechanistic studies in valid animal models of human NAFLD. Prospective cohort studies and possibly randomized controlled trials are also needed to elucidate the diagnostic and therapeutic potential of Se supplementation in selected NAFLD individuals with Se deficiency.

The Role of Micronutrients in the Infection and Subsequent Response to Hepatitis C Virus

Micronutrient deficiencies develop for a variety of reasons, whether geographic, socioeconomic, nutritional, or as a result of disease pathologies such as chronic viral infection. As micronutrients are essential for a strong immune response, deficiencies can significantly dampen both the innate and the adaptive arms of antiviral immunity. The innate immune response in particular is crucial to protect against hepatitis C virus (HCV), a hepatotropic virus that maintains chronic infection in up to 80% of individuals if left untreated. While many micronutrients are required for HCV replication, an overlapping group of micronutrients are also necessary to enact a potent immune response. As the liver is responsible for the storage and metabolism of many micronutrients, HCV persistence can influence the micronutrients' steady state to benefit viral persistence both directly and by weakening the antiviral response. This review will focus on common micronutrients such as zinc, iron, copper, selenium, vitamin A, vitamin B12, vitamin D and vitamin E. We will explore their role in the pathogenesis of HCV infection and in the response to antiviral therapy. While chronic hepatitis C virus infection drives deficiencies in micronutrients such as zinc, selenium, vitamin A and B12, it also stimulates copper and iron excess; these micronutrients influence antioxidant, inflammatory and immune responses to HCV.

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.

Hepatic ZIP8 deficiency is associated with disrupted selenium homeostasis, liver pathology, and tumor formation

Zrt/Irt-like protein 8 (ZIP8) (encoded by Slc39a8) is a multifunctional membrane transporter that influxes essential metal cations Zn2+, Mn2+, Fe2+, and nonmetal inorganic selenite (HSeO3-). Physiological roles of ZIP8 in different cell types and tissues remain to be elucidated. We aimed to investigate ZIP8 functions in liver. Two mouse models were used in this study: 1) 13- to 21-mo-old Slc39a8(+/neo) hypomorphs having diminished ZIP8 levels and 2) a liver-specific ZIP8 acute knockdown mouse (Ad-shZip8). Histology, immunohistochemistry, and Western blotting were used to investigate ZIP8-deficiency effects on hepatic injury, inflammatory changes, and oxidative stress. Selenium (Se) and zinc (Zn) were quantified in tissues by inductively coupled plasma-mass spectrophotometry. We found that ZIP8 is required to maintain normal liver function; moderate or acute decreases in ZIP8 activity resulted in hepatic pathology. Spontaneous liver neoplastic nodules appeared in ~50% of Slc39a8(+/neo) between 13 and 21 mo of age, exhibiting features of inflammation, fibrosis, and liver injury. In Ad-shZip8 mice, significant hepatomegaly was observed; histology showed ZIP8 deficiency was associated with hepatocyte injury, inflammation, and proliferation. Significant decreases in Se, but not Zn, were found in Ad-shZip8 liver. Consistent with this Se deficit, liver expression of selenoproteins glutathione peroxidases 1 and 2 was downregulated, along with decreases in antioxidant superoxide dismutases 1 and 2, consistent with increased oxidative stress. Thus, ZIP8 plays an important role in maintaining normal hepatic function, likely through regulating Se homeostasis and redox balance. Hepatic ZIP8 deficiency is associated with liver pathology, including oxidative stress, inflammation, proliferation, and hepatocellular injury. NEW & NOTEWORTHY Zrt/Irt-like protein 8 (ZIP8) is a multifunctional membrane transporter that facilitates biometal and mineral uptake. The role of ZIP8 in liver physiology has not been previously investigated. Liu et al. discovered unique ZIP8 functions, i.e., regulation of hepatic selenium content and association of ZIP8 deficiency in mouse liver with liver defects.

Determination of selenium during pathogenesis of hepatic fibrosis employing hydride generation and inductively coupled plasma mass spectrometry

Serum and liver selenium levels were studied during the pathogenesis of N-nitrosodimethylamine (NDMA) induced hepatic fibrosis in rats. The degree of fibrosis was assessed with Masson’s trichrome staining and quantifying collagen content in the liver. Lipid peroxides were measured in blood and liver samples and total glutathione and glutathione peroxidase were assayed in the liver tissue to evaluate oxidative stress. Interleukin-6 (IL-6) and transforming growth factor-β1 (TGF-β1) were measured in the serum. Selenium levels were determined using inductively coupled plasma-mass spectrometry (ICP-MS) after acid digestion and hydride generation of selenium. Serial administrations of NDMA produced well-developed fibrosis and early cirrhosis in the liver with 4-fold increase of total collagen content and deposition of collagen fibers. Blood and hepatic lipid peroxides, serum IL-6 and TGF-β1 were significantly increased. There was significant reduction in hepatic glutathione and glutathione peroxidase levels. Serum and liver selenium were remarkably decreased on all the days studied. The results suggest that decreased selenium and glutathione peroxidase contribute to the impairment of cellular antioxidant defense, which in turn results in oxidative stress and trigger pathogenesis of hepatic fibrosis. The study further demonstrated that ICP-MS with hydride generation technique is a reliable and sensitive method for determination of selenium in biological samples.

The Hepatoprotective Effect of Selenium-Enriched Yeast and Gum Arabic Combination on Carbon Tetrachloride-Induced Chronic Liver Injury in Rats

The antioxidant and anti-inflammatory effects of selenium-enriched yeast (SY) and Gum Arabic (GA) have been reported. This study aimed to determine the hepatoprotective effect of SY and GA combination on carbon tetrachloride (CCl₄ )-induced chronic liver injury in rats and to explore their synergistic mechanisms of action. Forty adult male Wistar rats randomly allotted to 5 groups: (A) worked as control, (B) was administered CCl₄ , (C-E) were fed daily by GA, SY, and GA+SY respectively after mixing with basal diet, following CCl₄ -intoxication. GA and SY combination significantly ameliorated CCl₄ -induced reduction in serum total protein with elevation in aspartate transaminase (AST) and alanine transaminase (ALT) in addition to restoring the histopathological changes and hepatic content of hydroxyproline. GA and SY combination was also effective in reducing lipid peroxidation (MDA), consistent with an increase in total antioxidant capacity (T-AOC), glutathione (GSH), superoxide dismutase (SOD) activities, indicating the suppression of liver oxidative stress. Furthermore, liver inflammation was ameliorated by GA and SY combination through inhibition of nuclear factor-kappa (NF-κB), tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2(COX-2), monocyte chemotactic protein-1 (MCP-1), and toll-like receptor 4(TLR-4) over expression in the liver. Moreover, the up-regulation of proliferating cell nuclear antigen (PCNA) expression by GA and SY combination enhanced the regeneration of liver tissue after CCl₄ -administration. The expression of Collagen1, alpha-smooth muscle actin (α-SMA), and transforming growth factor-beta1 (TGFβ1), was obviously ameliorated by GA and SY combination, suggesting the amelioration of profibrotic response of the liver. Taken together, our current study suggests that GA and SY combination exhibit a significant hepatoprotective activity, which more efficient than GA or SY alone.

PRACTICAL APPLICATION

Chronic liver diseases are the serious health problems, which increase the morbidity and mortality in the world today. Selenium-enriched yeast (SY) and Gum Arabic (GA) combination might be potential dietary agents could obviously ameliorate chronic liver damage, higher than GA and SY alone. They act to suppress the inflammation and inhibit the profibrotic response as well as support the liver regeneration.

Associations between Zinc Deficiency and Metabolic Abnormalities in Patients with Chronic Liver Disease

Zinc (Zn) is an essential trace element which has favorable antioxidant, anti-inflammatory, and apoptotic effects. The liver mainly plays a crucial role in maintaining systemic Zn homeostasis. Therefore, the occurrence of chronic liver diseases, such as chronic hepatitis, liver cirrhosis, or fatty liver, results in the impairment of Zn metabolism, and subsequently Zn deficiency. Zn deficiency causes plenty of metabolic abnormalities, including insulin resistance, hepatic steatosis and hepatic encephalopathy. Inversely, metabolic abnormalities like hypoalbuminemia in patients with liver cirrhosis often result in Zn deficiency. Recent studies have revealed the putative mechanisms by which Zn deficiency evokes a variety of metabolic abnormalities in chronic liver disease. Zn supplementation has shown beneficial effects on such metabolic abnormalities in experimental models and actual patients with chronic liver disease. This review summarizes the pathogenesis of metabolic abnormalities deriving from Zn deficiency and the favorable effects of Zn administration in patients with chronic liver disease. In addition, we also highlight the interactions between Zn and other trace elements, vitamins, amino acids, or hormones in such patients.

Management of Parenteral Nutrition in Hospitalized Adult Patients [Formula: see text]

Despite the high prevalence of malnutrition in adult hospitalized patients, surveys continue to report that many clinicians are undertrained in clinical nutrition, making targeted nutrition education for clinicians essential for best patient care. Clinical practice models also continue to evolve, with more disciplines prescribing parenteral nutrition (PN) or managing the cases of patients who are receiving it, further adding to the need for proficiency in general PN skills. This tutorial focuses on the daily management of adult hospitalized patients already receiving PN and reviews the following topics: (1) PN basics, including the determination of energy and volume requirements; (2) PN macronutrient content (protein, dextrose, and intravenous fat emulsion); (3) PN micronutrient content (electrolytes, minerals, vitamins, and trace elements); (4) alteration of PN for special situations, such as obesity, hyperglycemia, hypertriglyceridemia, refeeding, and hepatic/renal disease; (5) daily monitoring and adjustment of PN formula; and (6) PN-related complications (PN-associated liver disease and catheter-related complications).

Alcoholic liver disease: focus on prodromal gut health

Alcoholic liver disease (ALD) is implicated in gut disturbances, both functionally and structurally. It has been noticed that the gut-liver interaction is an important feature in the prevention of systemic inflammation as well as liver health. The optimal functioning of the gut-liver axis depends on gut health. Therefore, gut problems may be important for estimating liver inflammation, while our knowledge of ALD could also provide an insight into gut health. Gut problems accompanied by ALD include gut motility and absorption problems, mucosal damage and the dysbiosis of gut microbiota and gastrointestinal carcinogenesis. Moreover, there is emerging evidence that besides direct inflammatory injury caused by alcohol, gut problems related to ALD play a crucial role in the pathogenesis of cardiovascular and immunological disorders. In this regard, we should consider ALD in relation to both gut health and chronic systemic low-grade inflammation. Accordingly, integrative therapeutic strategies are warranted for treating and preventing ALD and systemic inflammation as well as alcohol-related gut problems.

Selenium Protects Retinal Cells from Cisplatin-Induced Alterations in Carbohydrate Residues

BACKGROUND

Investigate alterations in the expression and localization of carbohydrate units in rat retinal cells exposed to cisplatin toxicity.

AIMS

The aim of the study was to evaluate putative protective effects of selenium on retinal cells subjected to cisplatin.

STUDY DESIGN

Animal experiment.

METHODS

Eighteen healthy Wistar rats were divided into three equal groups: 1. Control, 2. Cisplatin and 3. Cisplatin+selenium groups. After anesthesia, the right eye of each rat was enucleated.

RESULTS

Histochemically, retinal cells of control groups reacted with α-2,3-bound sialic acid-specific Maackia amurensis lectin (MAA) strongly, while cisplatin reduced the staining intensity for MAA. However, selenium administration alleviated the reducing effect of cisplatin on the binding sites for MAA in retinal cells. The staining intensity for N-acetylgalactosamine (GalNAc residues) specific Griffonia simplicifolia-1 (GSL-1) was relatively slight in control animals and cisplatin reduced this slight staining for GSL-1 further. Selenium administration mitigated the reducing effect of cisplatin on the binding sites for GSL-1. A diffuse staining for N-acetylglucosamine (GlcNAc) specific wheat germ agglutinin (WGA) was observed throughout the retina of the control animals. In particular, cells localized in the inner plexiform and photoreceptor layers are reacted strongly with WGA. Compared to the control animals, binding sites for WGA in the retina of rats given cisplatin were remarkably decreased. However, the retinal cells of rats given selenium reacted strongly with WGA.

CONCLUSION

Cisplatin reduces α-2,3-bound sialic acid, GlcNAc and GalNAc residues in certain retinal cells. However, selenium alleviates the reducing effect of cisplatin on carbohydrate residues in retinal cells.

Nutrition in Chronic Liver Disease

Protein-calorie malnutrition is a transversal condition to all stages of chronic liver disease. Early recognition of micro or macronutrient deficiencies is essential, because the use of nutritional supplements reduces the risk of complications. The diet of patients with chronic liver disease is based on a standard diet with supplements addition as necessary. Restrictions may be harmful and should be individualized. Treatment management should aim to maintain an adequate protein and caloric intake and to correct nutrient deficiencies. The large majority of patients with grade I/II hepatic encephalopathy can tolerate a regular diet. Protein restriction can aggravate malnutrition and is not recommended, except in cases of hepatic encephalopathy unresponsive to optimized therapy.

Selenium deficiency occurs in some patients with moderate-to-severe cirrhosis and can be corrected by administration of selenate but not selenomethionine: a randomized controlled trial

BACKGROUND

Selenomethionine, which is the principal dietary form of selenium, is metabolized by the liver to selenide, which is the form of the element required for the synthesis of selenoproteins. The liver synthesizes selenium-rich selenoprotein P (SEPP1) and secretes it into the plasma to supply extrahepatic tissues with selenium.

OBJECTIVES

We conducted a randomized controlled trial to determine whether cirrhosis is associated with functional selenium deficiency (the lack of selenium for the process of selenoprotein synthesis even though selenium intake is not limited) and, if it is, whether the deficiency is associated with impairment of selenomethionine metabolism.

DESIGN

Patients with Child-Pugh (C-P) classes A, B, and C (mild, moderate, and severe, respectively) cirrhosis were supplemented with a placebo or supranutritional amounts of selenium as selenate (200 or 400 μg/d) or as selenomethionine (200 μg/d) for 4 wk. Plasma SEPP1 concentration and glutathione peroxidase (GPX) activity, the latter due largely to the selenoprotein GPX3 secreted by the kidneys, were measured before and after supplementation.

RESULTS

GPX activity was increased more by both doses of selenate than by the placebo in C-P class B patients. The activity was not increased more by selenomethionine supplementation than by the placebo in C-P class B patients. Plasma selenium was increased more by 400 μg Se as selenate than by the placebo in C-P class C patients. Within the groups who responded to selenate, there was a considerable variation in responses.

CONCLUSION

These results indicate that severe cirrhosis causes mild functional selenium deficiency in some patients that is associated with impaired metabolism of selenomethionine. This trial was registered at clinicaltrials.gov as NCT00271245.

Supplementation with selenium can influence nausea, fatigue, physical, renal, and liver function of children and adolescents with cancer

The drugs used in chemotherapy treatments have little specificity, attack tumor cells, and also injure proliferative tissues. Knowledge of the functions of micronutrients has greatly increased, especially of Selenium (Se) that presents immunomodulatory and antitumor functions. The present study evaluated the health-related quality of life of patients undergoing chemotherapy for the treatment of leukemias and lymphomas (LL) and solid tumors (ST) while receiving Selenium (Se) supplementation. This is a randomized, double-blind, crossover study that evaluated the quality of life (EORTC-QLQ-C30 questionnaire), renal and liver functions of patients supplemented with Se. There was no statistically significant alteration in LL patients. However, the fatigue and nausea scores after 30 days did decrease in this group as well as in the ST group. After 1 year supplementation with Selenium, a more noticeable decrease in the scores concerning fatigue and nausea could be observed in the ST group, when compared with the beginning of the study. The LL patients also presented a decrease in the fatigue scores and physical functions. The kidney function as well as liver function has improved after Selenium supplementation when compared with the placebo intake in LL and ST patients, more remarkably in the LL group. Supplementation with Selenium promotes the reduction of chemotherapy side effects in cancer patients, especially by improving the conditions of patients with fatigue, nausea, and impaired physical function. Renal and liver functions have also improved.

Hepatoprotective Evaluation of Ganoderma lucidum Pharmacopuncture: In vivo Studies of Ethanol-induced Acute Liver Injury

OBJECTIVES

Alcohol abuse is a public issue and one of the major causes of liver disease worldwide. This study was aimed at investigating the protective effect of Ganoderma lucidum pharmacopuncture (GLP) against hepatotoxicity induced by acute ethanol (EtOH) intoxication in rats.

METHODS

Sprague-Dawley (SD) rats were divided into 4 groups of 8 animals each: normal, control, normal saline pharmacopuncture (NP) and GLP groups. The control, NP and GLP groups received ethanol orally. The NP and the GLP groups were treated daily with injections of normal saline and Ganoderma lucidum extract, respectively. The control group received no treatment. The rats in all groups, except the normal group, were intoxicated for 6 hours by oral administration of EtOH (6 g/kg BW). The same volume of distilled water was administered to the rats in the normal group. Two local acupoints were used: Qimen (LR14) and Taechung (LR3). A histopathological analysis was performed, and the liver function and the activities of antioxidant enzymes were assessed.

RESULTS

GLP treatment reduced the histological changes due to acute liver injury induced by EtOH and significantly reduced the increase in the alanine aminotransferase (ALT) enzyme; however, it had an insignificant effect in reducing the increase in aspartate aminotransferase (AST) enzyme. It also significantly ameliorated the superoxide dismutase (SOD) and the catalase (CAT) activities.

CONCLUSION

The present study suggests that GLP treatment is effective in protecting against ethanol-induced acute hepatic injury in SD rats by modulating the activities of ethanol-metabolizing enzymes and by attenuating oxidative stress.

Protective effects of Selenium-enriched probiotics on carbon tetrachloride-induced liver fibrosis in rats

This study aimed to investigate the effects of Se-enriched probiotics (SP) on the liver fibrosis induced by CCl4 in rats. The results showed that SP significantly decreased serum alanine aminotransferase (87.0 ± 1.96 U/L), aspartate aminotransferase (101 ± 3.13 U/L), hepatic hydroxyproline (898 ± 72.5 μg/g), and malondialdehyde (2.39 ± 0.34 nmol/mg) levels, but increased glutathione peroxidase (37.2 ± 3.19 U/mg), superoxide dismutase (201 ± 19.2 U/mg), and glutathione levels (3.32 ± 0.25 mg/g) (P < 0.05) in rats treated by CCl4. SP suppressed hepatic inflammation and necrosis induced by CCl4. Moreover, SP significantly reduced the expression of α-smooth muscle actin, collagen, TGF-β1, TIMP-1, and inflammation-related gene and induced apoptosis of activated hepatic stellate cells (P < 0.05) in rats treated by CCl4. Our results suggest that SP could protect the liver from fibrosis by attenuating hepatic oxidative stress, suppressing hepatic inflammation, and inducing apoptosis of hepatic stellate cells.

The role of nitric oxide and autophagy in liver injuries induced by selenium deficiency in chickens

Selenium (Se) is recognized as a necessary trace mineral in animal diets, including those of birds.

Effects of dietary selenium deficiency on mRNA levels of twenty-one selenoprotein genes in the liver of layer chicken

Selenium (Se) is an essential trace element in many life forms due to its occurrence as selenocysteine (Sec) residue in selenoproteins. However, little is known about the expression pattern of selenoproteins in the liver of layer chicken. To investigate the effects of Se deficiency on the mRNA expressions of selenoproteins in the liver tissue of layer chickens, 1-day-old layer chickens were randomly allocated into two groups (n=120/group). The Se-deficient group (-Se) was fed a Se-deficient corn-soy basal diet; the Se-adequate group as control (+Se) was fed the same basal diet supplemented with Se at 0.15 mg/kg (sodium selenite). The liver tissue was collected and examined for mRNA levels of 21 selenoprotein genes at 15, 25, 35, 45, 55, and 65 days old. The data indicated that the mRNA expressions of Gpx1, Gpx2, Gpx3, Gpx4, Sepn1, Sepp1, Selo, Sepx1, Selu, Txnrd1, Txnrd2, Txnrd3, Dio1, Dio2, SPS2, Selm, SelPb, Sep15, and Sels were decreased (p<0.05), but not the levels of Dio3 and Seli (p>0.05). The results showed that the mRNA levels of 19 selenoprotein (except Seli and Dio3) genes in the layer chicken liver were regulated by diet Se level. The present study provided some compensated data about the roles of Se in the regulation of selenoproteins.

Serum selenium levels and oxidative balance as differential markers in hepatic damage caused by alcohol

AIMS

Antioxidant system abnormalities have been associated with ethanol consumption. This study examines the effects of chronic ethanol consumption on oxidative balance, including selenium (Se) levels in alcoholic patients with or without liver disease, and if these measurements could be indicative of liver disease.

MAIN METHODS

Serum Se levels, antioxidant enzymes' activities, malondialdehyde (MDA) and protein carbonyl (PC) were determined in three groups of patients: alcoholics without liver disease, alcoholics with liver disease, and non-alcoholics with liver disease; and in healthy volunteers.

KEY FINDINGS

Serum Se levels were lower in alcoholic patients and in patients affected by liver disease and especially lower in the alcoholic liver disease group. These values were correlated with the activity of glutathione peroxidase (GPx), the antioxidant selenoprotein. The antioxidant activities of the glutathione reductase (GR) and superoxide dismutase (SOD) were also lower in the three non-healthy groups. However, GR activity decreased and SOD activity increased in the non-alcoholic liver disease group versus alcoholic groups. Higher concentrations of PC in serum were found in non-healthy groups and were higher in alcoholic patients who also showed higher MDA levels. The highest MDA and PC levels were found in the alcoholic liver disease group.

SIGNIFICANCE

We conclude that serum Se levels are drastically decreased in alcoholic liver disease patients, showing that this element has a direct correlation with GPx activity, and lipid oxidation, suggesting that the serum Se/MDA ratio could be an indicator of hepatic damage caused by alcohol consumption, and pointing to Se as a possible antioxidant therapy.

Relative and combined effects of selenium, protein deficiency and ethanol on hepatocyte ballooning and liver steatosis

Oxidative damage plays a key role in alcohol-mediated liver alterations. Selenium, a potent antioxidant, is decreased in alcoholics. This study was conducted to analyse if the supplementation with selenium may alter liver changes in a murine model fed ethanol and/or a 2 % protein-containing diet, following the Lieber-DeCarli design. Adult male Sprague Dawley rats were divided into eight groups which received the Lieber-DeCarli control diet; an isocaloric, 36 % ethanol-containing diet; an isocaloric, 2 % protein-containing diet; and an isocaloric diet containing 2 % protein and 36 % ethanol diet; and other similar four groups to which selenomethionine (1 mg/kg body weight) was added. After sacrifice (5 weeks later), liver fat amount and hepatocyte areas of pericentral and periportal cells were measured, and liver and serum selenium, activity of liver glutathione peroxidase (GPX), and liver malondialdehyde were determined. Ethanol-fed rats showed increased hepatocyte areas and fat accumulation especially when ethanol was added to a 2 % protein diet. Selenium caused a decrease in hepatocyte ballooning and liver fat amount, but an increase in GPX activity, and a marked increase in serum and liver selenium. The present study demonstrates that selenium, added to the diet of rats in the form of seleniomethionine, prevents the appearance of early signs of ethanol-mediated liver injury under the conditions of the Lieber-DeCarli experimental design.

Serum selenium levels in Korean hepatoma patients

The aim of this study was to determine serum selenium (Se) levels during the development of liver disease as well as the possible Se supplementation benefits in liver disease patients. Serum was collected from 187 patients with liver diseases and 120 normal healthy people living in Seoul. The samples were collected at the Kangnam St. Mary's Hospital College of Medicines, The Catholic University of Korea, in accordance with procedures approved by the Institutional Review Board of the Catholic University of Korea. Serum Se levels were quantified by inductively coupled plasma mass spectrometry and were compared between healthy and liver diseases patients. Se levels were 92.65 ± 32.50 μg/l in hepatitis infection, 92.33 ± 30.66 μg/l in hepatitis B virus infection and 96.41 ± 51.50 μg/l in hepatitis C virus infection, 96.42 ± 32.80 μg/l in cirrhosis, and 67.47 ± 14.30 μg/l in hepatoma patients. Findings were significantly lower in hepatitis and hepatoma as compared with the healthy participants (P < 0.001). The Se level of the healthy population was 108.38 ± 29.50, 119.37 ± 28.31 for males and 97.87 ± 26.99 μg/l for females. Our data shows the same parallelism between liver disease progression and decrease of Se levels except in the case of liver cirrhosis. And also, our study confirms the previous findings of significantly lower Se levels in Korean hepatoma patients. Se levels that decrease parallel to liver disease progression should be further integrated and analyzed with liver function blood biomarkers.

Selenium deficiency is associated with insulin resistance in patients with hepatitis C virus-related chronic liver disease

The relationship between selenium (Se) deficiency and insulin resistance has not much been established in persistent hepatitis C virus (HCV) infection, although Se deficiency is often observed in patients with liver cirrhosis. We hypothesized that the decreased serum Se levels were associated with the severity of hepatic fibrosis or insulin resistance in patients with HCV-related chronic liver disease (CLD). To test the hypothesis, 52 patients with HCV-related CLD including chronic hepatitis and liver cirrhosis were enrolled in this study. The severity of hepatic fibrosis was divided into 4 categories (F(1) through F(4)) according to the new Inuyama classification. Insulin resistance was defined by the homeostasis model for assessment of insulin resistance value. Serum Se levels significantly declined in proportion to the severity of hepatic fibrosis and were positively correlated with serum albumin (r = 0.372, P = .0065) and zinc (r = 0.403, P = .0081) concentrations. Serum Se levels were also linked to glutathione peroxidase activities in the sera of the enrolled patients (r = 0.374, P = .0148). By contrast, serum Se levels were inversely correlated with the homeostasis model for assessment of insulin resistance values (r = -0.304, P = .0338). However, serum Se levels were independent of HCV genotype and loads of HCV-RNA. These findings suggest that Se deficiency was associated with the severity of hepatic fibrosis in patients with HCV-related CLD and that Se deficiency was likely to be one of the factors contributing to insulin resistance in those patients.

Selenium levels in men with liver disease in Hungary

PROJECT

We studied the relationship between selenium (Se) levels and chronic liver disease (CLD) severity and the association between socioeconomic and lifestyle factors and serum Se levels.

PROCEDURE

We performed a case-control study in Hungarian men, examining 281 patients with CLD and 778 controls. Liver function was evaluated using biochemical markers, and liver disease was verified with physical examination and blood tests. Linear regression analysis was performed to study the association of serum Se level with biochemical markers in cases and controls. In control participants we examined the relationship between Se levels and age, financial status, education, alcohol consumption, cigarette smoking, type of fat used for cooking and body mass index.

RESULTS

Serum Se levels were lower in cases (median 0.87 μmol/L (IQR: 0.77-1.03)) than in controls (median 1.08 μmol/L (IQR: 0.97-1.19)). In controls, increases in bilirubin and glutamic-oxaloacetic transaminase (GOT) were associated with decreases in Se levels. In patients with CLD, a statistically significant relationship was found between serum Se and the GOT/GPT ratio, albumin and bilirubin. Younger, better-educated controls had significantly higher, and regular smokers and heavy drinkers had significantly lower Se levels. The use of vegetable oil/fat was also associated with higher Se levels. Se level was associated with the severity of liver injury in people even in patients who did not exhibit signs and symptoms of CLD.

CONCLUSIONS

Serum Se level is strongly associated with the severity of liver damage in people with CLD from the early stage on.

The combination of selenium and vitamin E inhibits type I collagen formation in cultured hepatic stellate cells

This study investigated the effects of sodium selenite (Se) and of vitamin E (D-α-tochopherol) on the deposition of type I collagen by human LX-2 stellate cells. The cultured cells were treated with or without Se or vitamin E and with or without transforming growth factor β1 (TGFβ1). The combination of Se and vitamin E, but not either alone, protected against hepatic fibrosis by decreasing TGFβ1-mediated collagen secretion and accumulation by the stellate cells. This protective effect is due to a combination of decreased formation, decreased stability and increased degradation of the collagen. Effects of Se and vitamin E in decreasing α(1)(I) collagen mRNA and increasing apoptosis of stellate cells indicate decreased formation of collagen, while decreases in transglutaminase 2, which catalyze cross-linking of collagen, lead to decreased stability of the secreted collagen. Effects of Se and vitamin E on reducing tissue inhibitor metalloproteinase 1 (TIMP-1) are associated with increased degradation. The combination of Se and vitamin E decreased lipid peroxidation, while Se alone increased the activity of the antioxidant enzyme thioredoxin reductase. In conclusion, the combination of Se and vitamin E protected against TGFβ1-mediated hepatic fibrosis by decreasing TGFβ1-mediated type I collagen accumulation by stellate cells. This effect is due to a combination of decreased formation, decreased stability and increased degradation of the collagen.

Relative and combined effects of selenium, protein deficiency and ethanol on bone

Some observations suggest that oxidative damage may affect both osteoblastic function and osteoclastic activity in alcohol-mediated bone alterations. Selenium, a potent antioxidant, is decreased in alcoholics.

OBJECTIVE

To analyse if the supplementation with selenium may alter bone changes observed in a murine model fed ethanol and/or a 2% protein-containing diet, following the Lieber-deCarli design.

MATERIAL AND METHOD

Adult male Sprague-Dawley rats were divided into 8 groups, which received the Lieber-DeCarli control diet, an isocaloric, 36% ethanol-containing diet, an isocaloric, 2% protein-containing diet; and an isocaloric diet containing 2% protein and 36% ethanol diet, and another similar four groups to which selenomethionine (1mg/kg body weight). After sacrifice (5 weeks later), trabecular bone mass was histomorphometrically assessed, bone and serum selenium were determined by flame atomic absorption spectrophotometry, and serum osteocalcin, insulin growth factor 1 (IGF-1), PTH and telopeptide, by radioimmunoanalysis. Liver glutathione peroxidase (GPX) activity was also determined.

RESULTS

Ethanol-fed rats showed decreased TBM, IGF-1 and osteocalcin, especially when ethanol was added to a 2%-protein diet. Selenium did not modify at all bone parameters, despite a marked increase in serum selenium and a less pronounced one in bone selenium, and an increase in liver GPX.

CONCLUSION

Our results do not support the existence of a beneficial effect of selenium addition on bone changes observed in this murine model treated following the Lieber-deCarli experimental design.

Serum selenium levels in cirrhotic patients are not influenced by the disease severity index

Selenium (Se) is an antioxidant element that protects against cellular damage by reactive oxygen species. Therefore, total serum Se concentration may reflect protection during the development of cirrhosis, an oxidative stress-related disease. We hypothesized that serum Se levels are diminished in cirrhotic patients due to their enhanced oxidative stress, and serum Se levels are reduced the most in patients with the highest severity of cirrhosis. A case-control study was performed to determine whether cirrhosis is associated with changes in serum Se levels. Blood samples from 30 healthy controls and 93 cirrhotic patients were analyzed for total serum Se by hydride generation atomic absorption spectrometry. The Child-Pugh index score was used to evaluate the severity of liver disease. The mean serum Se concentration was significantly lower in patients vs controls (0.721 ± 0.239 vs 0.926 ± 0.241 μmol/L; P = .001). Mean serum Se levels were not significantly lower in patients with higher severity of cirrhosis (0.691 ± 0.229 vs 0.755 ± 0.255 μmol/L; P = .144). A positive and significant correlation was found between age and serum Se levels in patients (r = 0.277, P = .007). Patients showed significant sex differences in serum Se level (higher in male) and severity index (higher in female). The significantly decreased serum Se level in patients indicates that the Se component of the antioxidant system is severely impaired in cirrhosis. However, serum Se levels were not influenced by the severity of the disease.

Selenium supplementation decreases hepatic fibrosis in mice after chronic carbon tetrachloride administration

Oxidative stress stimulates fibrogenesis, and selenium (Se) has antioxidant properties. This study determined whether Se supplementation affects CCl(4)-induced liver injury and fibrosis. Mice were administered CCl(4) over 4 weeks, while controls received olive oil. Se was provided as sodium selenite in the drinking water. Se increased liver Se-dependent glutathione peroxidase activity and decreased liver malondialdehyde after CCl(4). Se decreased liver inflammation but not necrosis caused by CCl(4). Se increased hepatocyte apoptosis after CCl(4) and the pro-apoptotic BAX and Bcl Xs/l proteins. Stellate cell apoptosis occurred only after CCl(4) in Se-supplemented mice. Se decreased stellate cell number and fibrosis after CCl(4). Liver matrix metalloproteinase-9 increased after CCl(4) with Se supplementation. In conclusion, Se supplementation decreased hepatic fibrosis after CCl(4) in the setting of decreased inflammation but increased apoptosis. The principal mechanisms for the decreased fibrosis are a lower number of collagen-producing stellate cells and increased collagen degradation.

Relative and combined effects of chronic alcohol consumption and HCV infection on serum zinc, copper, and selenium

In alcoholic hepatitis, Kupffer cells are activated by intestinal gram-bacteria, leading to cytokine production and free radicals release, which, enhancing cytokine secretion, create a positive feedback loop which contributes to liver inflammation. Free radicals also damage the liver in chronic hepatitis C virus (HCV) infection, a condition frequently associated to alcohol consumption. In both situations, activity of antioxidant enzymes and of its cofactors zinc (Zn), selenium (Se), and copper (Cu) is important. This study was performed to assess the relative and combined effects of chronic alcoholism and HCV infection on serum Se, Zn, and Cu, and its relation with serum malondialdehyde (MDA) and tumor necrosis factor-α, interferon-γ, and interleukins (IL) 4, 6, and 8, in 19 HCV- alcoholic patients, 12 HCV+ alcoholic patients, nine HCV+ non-alcoholic patients, and 20 controls. Serum Zn and Se were lower in both HCV+ and HCV- alcoholic patients, whereas serum Cu was lower in HCV+ individuals. Serum Zn and Se were related to liver function derangement. MDA levels were higher in alcoholics, but no relation was observed between trace elements and MDA or cytokines, so that our results do not support a relevant role of the analyzed trace elements in the pathogenesis of chronic liver disease.

Glutathione peroxidase and liver diseases

Glutathione peroxidase is one of the most important components of anti-peroxidation system of the body and has been implicated in some diseases. Liver is an important organ where oxidative stress is generated. A close relationship between glutathione peroxidase and liver diseases has been reported in many studies. In this article, we will review the recent advances in understanding the relationship between liver diseases and selenium-dependent glutathione peroxidase.

Hepatology - Guidelines on Parenteral Nutrition, Chapter 16

Parenteral nutrition (PN) is indicated in alcoholic steatohepatitis (ASH) and in cirrhotic patients with moderate or severe malnutrition. PN should be started immediately when sufficientl oral or enteral feeding is not possible. ASH and cirrhosis patients who can be sufficiently fed either orally or enterally, but who have to abstain from food over a period of more than 12 hours (including nocturnal fasting) should receive basal glucose infusion (2–3 g/kg/d). Total PN is required if such fasting periods last longer than 72 h. PN in patients with higher-grade hepatic encephalopathy (HE); particularly in HE IV° with malfunction of swallowing and cough reflexes, and unprotected airways. Cirrhotic patients or patients after liver transplantation should receive early postoperative PN after surgery if they cannot be sufficiently rally or enterally nourished. No recommendation can be made on donor or organ conditioning by parenteral administration of glutamine and arginine, aiming at minimising ischemia/reperfusion damage. In acute liver failure artificial nutrition should be considered irrespective of the nutritional state and should be commenced when oral nutrition cannot be restarted within 5 to 7 days. Whenever feasible, enteral nutrition should be administered via a nasoduodenal feeding tube.

ESPEN Guidelines on Parenteral Nutrition: hepatology

Parenteral nutrition (PN) offers the possibility to increase or to ensure nutrient intake in patients, in whom sufficient nutrition by oral or enteral alone is insufficient or impossible. Complementary to the ESPEN guideline on enteral nutrition of liver disease (LD) patients the present guideline is intended to give evidence-based recommendations for the use of PN in LD. For this purpose three paradigm conditions of LD were chosen: alcoholic steatohepatitis (ASH), liver cirrhosis and acute liver failure. The guideline was developed by an interdisciplinary expert group in accordance with officially accepted standards and is based on all relevant publications since 1985. The guideline was presented on the ESPEN website and visitors' criticism and suggestions were welcome and included in the final revision. PN improves nutritional state and liver function in malnourished patients with ASH. PN is safe and improves mental state in patients with cirrhosis and severe HE. Perioperative (including liver transplantation) PN is safe and reduces the rate of complications. In acute liver failure PN is a safe second-line option to adequately feed patients in whom enteral nutrition is insufficient or impossible.

Effect of supplementation with Se-enriched yeast and factors influencing Se concentration in plasma of transplant recipients

The aim of this study was to assess the bioavailability of selenium (Se) in Se-enriched yeast and the possible impact of age, sex and area of residence on the Se concentration in plasma in 179 transplant recipients, as Se clinical effects in the prevention of cutaneous epithelial lesions in organ transplant recipients has been reported elsewhere. Subjects were randomized to receive either 200 microg Se/day (group 1:91 patients) or placebo (group 2: 88 patients) for 3 years. Plasma Se levels were measured at the beginning of the study and after 4, 12, 24 and 36 months of Se or placebo supplementation. Initial plasma Se levels were 90.9+/-26.1 microg/L for placebo and 94.0+/-25.3 microg/L for Se-supplemented groups. At baseline, the Se level was not linked to sex and age but to area of residence, although the number of subjects in each area was insufficient to draw any conclusions. Plasma Se levels were statistically lower in cases of liver transplant compared to kidney and heart transplant (p=0.03). Over the 3-year period of supplementation, plasma Se in the supplemented subjects was significantly higher than in the placebo group (p<0.01) and there was an interaction (p<0.01) between supplementation and time for plasma Se. Supplementation with Se-enriched yeast significantly increased the Se concentration in plasma of the patients to a plateau: the mean plasma Se of the Se-supplemented patients increased to 164.7+/-35.8 microg/L at 4 months and then remained similar at 12 (176.1+/-48.3 microg/L), 24 (176.1+/-54.2 microg/L) and 36 (182.2+/-46.4 microg/L) months.

Prognostic value of serum selenium levels in alcoholics

In alcoholics, exposure of Kupffer cells to intestinal-borne Gram-negative bacteria increases free radical release, which may, in turn, enhance cytokine secretion, creating a positive feedback loop, which contributes to liver inflammation. Impaired antioxidant mechanisms further aggravates this scenario. Some trace elements, such as selenium, are main cofactors of antioxidant enzymes. Some authors have found low Se levels in alcoholics in relation either with undernutrition, liver dysfunction, or intensity of alcoholism, but in general, Se supplementation has no effect on survival. In this study we measured serum Se in 16 controls and 76 alcoholics, 34 of them cirrhotics, 68 of whom were followed up for a median period of 38 months; 17 died during this period. Se levels were lower in patients than in controls and were related to prothrombin activity and nutritional status, more closely to this last parameter (stepwise logistic regression analysis). Patients who died showed lower Se values than those who survived. Se values over the median were associated with better survival, assessed by Kaplan-Meier curves and log-rank test. However, in multivariate analysis (Cox regression model), prothrombin activity displaced serum Se as a prognostic factor. We conclude that serum Se levels are low in alcoholics; these low values depend more heavily on impaired nutrition but also on liver dysfunction; although low Se levels were associated with a higher mortality, prothrombin activity displaced serum Se when survival was assessed using Cox's regression model.