Relationship of blood trace elements to liver damage, nutritional status, and oxidative stress in chronic nonalcoholic liver disease

Nutritional Support for Liver Diseases

The liver is a key organ that is responsible for the metabolism of proteins, fats, and carbohydrates and the absorption and storage of micronutrients. Unfortunately, the prevalence of chronic liver diseases at various stages of advancement in the world population is significant. Due to the physiological function of the liver, its dysfunction can lead to malnutrition and sarcopenia, and the patient's nutritional status is an important prognostic factor. This review discusses key issues related to the diet therapy of patients with chronic liver diseases, as well as those qualified for liver transplantation and in the postoperative period.

Potential Harm of IQOS Smoke to Rat Liver

The Food and Drug Administration has recently classified the IQOS electronic cigarette as a modified-risk tobacco product. However, IQOS cigarettes still release various harmful constituents typical of conventional cigarettes (CCs), although the concentrations are markedly lower. Here, we investigated the damaging effects of IQOS smoking on the liver. Male Sprague Dawley rats were exposed, whole body, 5 days/week for 4 weeks to IQOS smoke (4 sticks/day), and hepatic xenobiotic metabolism, redox homeostasis and lipidomic profile were investigated. IQOS boosted reactive radicals and generated oxidative stress. Exposure decreased cellular reserves of total glutathione (GSH) but not GSH-dependent antioxidant enzymes. Catalase and xanthine oxidase were greater in the exposed group, as were various hepatic CYP-dependent monooxygenases (CYP2B1/2, CYP1A1, CYP2A1, CYP2E1-linked). Respiratory chain activity was unaltered, while the number of liver mitochondria was increased. IQOS exposure had an impact on the hepatic lipid profile. With regard to the expression of some MAP kinases commonly activated by CC smoking, IQOS increased the p-p38/p38 ratio, while erythroid nuclear transcription factor 2 (Nrf2) was negatively affected. Our data suggest that IQOS significantly impairs liver function, supporting the precautionary stance taken by the WHO toward the use of these devices, especially by young people and pregnant women.

Malnutrition in Patients with Liver Cirrhosis

Liver cirrhosis is an increasing public health threat worldwide. Malnutrition is a serious complication of cirrhosis and is associated with worse outcomes. With this review, we aim to describe the prevalence of malnutrition, pathophysiological mechanisms, diagnostic tools and therapeutic targets to treat malnutrition. Malnutrition is frequently underdiagnosed and occurs-depending on the screening methods used and patient populations studied-in 5-92% of patients. Decreased energy and protein intake, inflammation, malabsorption, altered nutrient metabolism, hypermetabolism, hormonal disturbances and gut microbiome dysbiosis can contribute to malnutrition. The stepwise diagnostic approach includes a rapid prescreen, the use of a specific screening tool, such as the Royal Free Hospital Nutritional Prioritizing Tool and a nutritional assessment by dieticians. General dietary measures-especially the timing of meals-oral nutritional supplements, micronutrient supplementation and the role of amino acids are discussed. In summary malnutrition in cirrhosis is common and needs more attention by health care professionals involved in the care of patients with cirrhosis. Screening and assessment for malnutrition should be carried out regularly in cirrhotic patients, ideally by a multidisciplinary team. Further research is needed to better clarify pathogenic mechanisms such as the role of the gut-liver-axis and to develop targeted therapeutic strategies.

Impact of Glutathione and Vitamin B-6 in Cirrhosis Patients: A Randomized Controlled Trial and Follow-Up Study

Vitamin B-6 and glutathione (GSH) are antioxidant nutrients, and inadequate vitamin B-6 may indirectly limit glutathione synthesis and further affect the antioxidant capacities. Since liver cirrhosis is often associated with increased oxidative stress and decreased antioxidant capacities, we conducted a double-blind randomized controlled trial to assess the antioxidative effect of vitamin B-6, GSH, or vitamin B-6/GSH combined supplementation in cirrhotic patients. We followed patients after the end of supplementation to evaluate the association of vitamin B-6 and GSH with disease severity. In total, 61 liver cirrhosis patients were randomly assigned to placebo, vitamin B-6 (50 mg pyridoxine/d), GSH (500 mg/d), or B-6 + GSH groups for 12 weeks. After the end of supplementation, the condition of patient’s disease severity was followed until the end of the study. Neither vitamin B-6 nor GSH supplementation had significant effects on indicators of oxidative stress and antioxidant capacities. The median follow-up time was 984 d, and 21 patients were lost to follow-up. High levels of GSH, a high GSH/oxidized GSH ratio, and high GSH-St activity at baseline (Week 0) had a significant effect on low Child–Turcotte–Pugh scores at Week 0, the end of supplementation (Week 12), and the end of follow-up in all patients after adjusting for potential confounders. Although the decreased GSH and its related enzyme activity were associated with the severity of liver cirrhosis, vitamin B-6 and GSH supplementation had no significant effect on reducing oxidative stress and increasing antioxidant capacities.

Oxidative Stress Management in Chronic Liver Diseases and Hepatocellular Carcinoma

Chronic viral hepatitis B and C and non-alcoholic fatty liver disease (NAFLD) have been widely acknowledged to be the leading causes of liver cirrhosis and hepatocellular carcinoma. As anti-viral treatment progresses, the impact of NAFLD is increasing. NAFLD can coexist with chronic viral hepatitis and exacerbate its progression. Oxidative stress has been recognized as a chronic liver disease progression-related and cancer-initiating stress response. However, there are still many unresolved issues concerning oxidative stress, such as the correlation between the natural history of the disease and promising treatment protocols. Recent findings indicate that oxidative stress is also an anti-cancer response that is necessary to kill cancer cells. Oxidative stress might therefore be a cancer-initiating response that should be down regulated in the pre-cancerous stage in patients with risk factors for cancer, while it is an anti-cancer cell response that should not be down regulated in the post-cancerous stage, especially in patients using anti-cancer agents. Antioxidant nutrients should be administered carefully according to the patients’ disease status. In this review, we will highlight these paradoxical effects of oxidative stress in chronic liver diseases, pre- and post-carcinogenesis.

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.

Evaluation of Plasma Trace Elements in Different Stages of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is considered as the hepatic manifestation of metabolic syndrome. Its global prevalence is estimated between 25 and 45%, occurring mainly in overweight individuals with unhealthy dietary habits and low levels of physical activity. Many studies have investigated the association of trace elements with liver diseases, though not with NAFLD. In this work, we investigated trace element levels in plasma of patients and not-patients and their possible association with various stages of the disease. Inductively coupled plasma mass spectrometry (ICP-MS) was employed for the determination of As, Ba, Cd, Co, Cs, Cu, Fe, Rb, Sr, Tl, and Zn in the plasma of 189 free-living residents of Athens, Greece, either healthy or patients with mild, moderate, or severe NAFLD. The disease was diagnosed by abdominal ultrasound; blood samples were analyzed for total, HDL and LDL cholesterol, triglycerides, fasting glucose, fasting insulin, and liver enzymes, namely aspartate aminotransferase (AST), alanine transaminase (ALT), and γ-glutamyltransferase (Gamma-GT); insulin resistance was determined by the homeostatic model assessment (HOMA-IR). Zinc exhibited a statistically significant negative association with the severity of the disease, while cesium showed a statistically significant positive association. Moreover, thallium and iron were inversely associated with insulin levels. Trace element determination in plasma could be useful for establishing relationships with NAFLD status of patients. Further research is required for the verification and interpretation of these findings.

Biomarkers of oxidative stress as an assessment of the redox status of the liver in dogs

Background

Oxidative stress is associated with a diverse group of liver disorders across species.

Objectives

Determine whether glutathione (GSH) concentration in plasma and red blood cells correlates with liver GSH concentration in dogs and evaluate whether other markers of systemic oxidative stress, plasma vitamin E and urine 8‐isoprostanes/creatinine (F₂‐IsoPs/Cr) concentrations, correlate with liver GSH.

Animals

Thirty‐four client‐owned dogs undergoing clinically indicated liver biopsy and 15 healthy control dogs.

Methods

Prospective, observational cross‐sectional study. Urine and blood were collected before liver biopsy. Plasma, erythrocyte, and liver GSH were measured using high performance liquid chromatography (HPLC); vitamin E was measured by HPLC, and F₂‐IsoPs/Cr was measured by gas chromatography/mass spectrometry.

Results

All dogs were treated at the discretion of the attending clinician (24/34 received antioxidants; 4/34 fed therapeutic liver diet), which included dogs with primary or secondary liver disease (inflammatory (n = 21), metabolic (n = 9), vascular (n = 2), and neoplastic (n = 2)). Median GSH concentrations in plasma, erythrocyte, and liver were 0.18 mg/dL (range 0.14 to 0.56 mg/dL), 56.7 mg/dL (18.3 to 79.2 mg/dL), and 181 mg/dL (39.9 to 527 mg/dL), respectively. No significant correlations were found between liver GSH and erythrocyte GSH, plasma GSH, vitamin E, or F₂‐IsoPs/Cr. Dogs undergoing clinically indicated liver biopsy had significantly higher urine F₂‐IsoPs/Cr than did healthy controls (5.89 vs 2.98 ng/mg; P < .0001).

Conclusions and Clinical Importance

Erythrocyte and plasma GSH are not indicative of liver GSH concentration in dogs. In addition, dogs undergoing clinically indicated liver biopsy have evidence of increased systemic oxidative stress compared to healthy controls.

TRACE ELEMENTS IN PLASMA AND NUTRITIONAL ASSESSMENT IN PATIENTS WITH COMPENSATED CIRRHOSIS ON A LIVER TRANSPLANT LIST

ABSTRACT Background - In chronic liver disease, trace element levels in plasma are usually low. However, the specific cause and functional implications of this abnormality are yet not well understood. These element levels may decrease as a result of abnormal liver function in patients with cirrhosis and/or malnutrition. Objective - To evaluate the nutritional status and the profile of trace elements in plasma of patients with cirrhosis on a liver transplant list and to correlate them with disease severity. Methods - This cross-sectional study evaluated 31 male patients diagnosed with compensated liver cirrhosis on a waiting list for liver transplant. Nutritional status was objectively evaluated through anthropometry using Mendenhall score and Blackburn classification, subjectively through the Detsky questionnaire and severity of the disease by MELD and CTP score. Trace elements (Zn, Se, Cu, Ca, Fe, Mg and Mn) in plasma were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Statistical analysis was performed using Mann-Whitney test. Results - According to the nutritional assessment 19 (61.3%) were malnourished and 12 (38.7%) were overweight. Regarding disease severity 12 (39%) were classified as Child A, 17 (55%), Child B and 2 (6%) Child C, with 46.9% of patients with MELD score >17. The trace element analysis indicated that 31 (100%) had Mn levels above the reference range, 23 (74.2%) low levels of Cu, 29 (93.5%) with deficiency of Se, and 31 (100%) low levels of Ca and Mg. Disease severity did not show statistical difference between the studied trace elements, in contrast to the nutritional status, in which the malnourished group showed higher levels of Mn (P=0.01) and Fe (P=0.01) and low levels of Zn (P=0.03) when compared to the overweight group. Conclusion - The results showed that the trace elements in plasma are altered in chronic liver disease; without significant correlation to disease severity, but correlated to nutritional status. Malnutrition is present in the patients studied, nonetheless a new scenario with an increase in the prevalence of overweight was verified regardless of the degree of hepatic decompensation.

High serum carotenoids are associated with lower risk for developing elevated serum alanine aminotransferase among Japanese subjects: the Mikkabi cohort study

Many recent studies have shown that antioxidant vitamins and/or carotenoids may reduce liver disease, but this association has not been well established with thorough longitudinal cohort studies. The objective of this study was to longitudinally investigate whether serum carotenoids at baseline are associated with the risk of developing elevated serum alanine aminotransferase (ALT) among Japanese subjects. We conducted a follow-up study of 1073 males and females aged between 30 and 79 years at baseline from the Mikkabi prospective cohort study. Those who participated in the baseline study and completed follow-up surveys were examined longitudinally. Exclusions included excessive alcohol consumption (≥60 g alcohol/d), hepatitis B and C and having a history of medication use for liver disease. A cohort of 213 males and 574 females free of elevated serum ALT (>30 IU/ml) at baseline was studied. Over a mean follow-up period of 7·4 (sd 3·1) years, thirty-one males and forty-nine females developed new elevated serum ALT. After adjustments for confounders, the hazard ratios for elevated serum ALT in the highest tertiles of basal serum β-carotene, β-cryptoxanthin and total provitamin A carotenoids against the lowest tertiles were 0·43 (95 % CI 0·22, 0·81), 0·51 (CI 0·27, 0·94) and 0·52 (CI 0·28, 0·97), respectively. For α-carotene and lycopene, borderline reduced risks were also observed; however, these were not significant. Our results further support the hypothesis that antioxidant carotenoids, especially provitamin A carotenoids, might help prevent earlier pathogenesis of non-alcoholic liver disease in Japanese subjects.

The WOMED model of benign thyroid disease: Acquired magnesium deficiency due to physical and psychological stressors relates to dysfunction of oxidative phosphorylation

BACKGROUND

The aim of this study was to discern whether a relation between biochemical parameters, sonography and musculoskeletal data exists in cases of hyperthyroidism and whether they are modifiable through supplementation with selenomethionine and magnesium citrate as well as by acupuncture and manual medicine methods.

RESULTS

A direct correlation between whole blood selenium and serum magnesium was found in subjects without thyroid disease and in menopausal women while it was reversed in cases of thyroid diseases as well as in patients with depression, infection, and in infertile women. Vascularization indices were elevated in cases of newly diagnosed benign thyroid diseases. Musculoskeletal changes i.e. lateral tension and idiopathic moving toes, as well as situations of physical and psychological stress and minor trauma and infection led to an increase of vascularization. Magnesium levels correlated negatively with these two conditions. The supplementation brought a reduction of the vascularization indices and reduced the incidence of idiopathic moving toes. Treatment of lateral tension required manual medicine methods and acupuncture (gastrocnemius). A small subgroup of patients showed a further reduction of hyper-vascularization after receiving coenzyme Q10.

CONCLUSIONS

We interpret the elevated thyroid vascularization and low magnesium levels as signs of an inflammatory process related to the musculoskeletal changes. Improvement of thyroid function and morphology can be achieved after correcting the influence of stressors together with the supplementation regime. We hypothesize that the central biochemical event in thyroid disease is that of an acquired, altered mitochondrial function due to deficiency of magnesium, selenium, and coenzyme Q10.

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.

High rates of serum selenium deficiency among HIV- and HCV-infected and uninfected drug users in Buenos Aires, Argentina

OBJECTIVE

To describe the prevalence of low serum Se and determine whether HIV, hepatitis C virus (HCV) and/or the types of drugs used are associated with serum Se in a cohort of infected and uninfected drug users.

DESIGN

Independent correlates of low serum Se levels based on data collected from food recalls, physical examinations and clinical questionnaires were identified using multivariate regression analysis.

SETTING

Buenos Aires, Argentina

SUBJECTS

A total of 205 (twenty-five female and 180 male) former and current drug users.

RESULTS

Drug users had an average serum Se level of 69·8 (sd 32·8) μg/d, [corrected] and 82 % were considered deficient (<85 μg/l). [corrected] Multivariate analyses found that HIV- and/or HCV-infected individuals had lower mean Se compared with healthy, uninfected drug users (HIV/HCV co-infection: -25·3 μg/l (se 7·6), P = 0·001; HIV alone: -28·9 μg/l (se 6·9), P < 0·001; HCV alone: -19·4 μg/l (se 7·1), P = 0·006). Current and previous drug use was associated with higher serum Se. Cigarette smoking and heavy alcohol consumption were not found to be associated with Se status.

CONCLUSIONS

Low serum Se levels are highly prevalent among drug users in Buenos Aires, Argentina. Se supplementation and/or dietary interventions may be warranted in drug users who are at high risk for HIV and/or HCV infection.

The impact of nutrition on cirrhotic patients awaiting liver transplantation

PURPOSE OF REVIEW

To review the most recent aspects of nutrition therapy of cirrhotic patients on the waiting list for liver transplantation.

RECENT FINDINGS

Undernutrition has been widely reported among these patients, despite the lack of consensus on the best nutritional assessment tools in this population. Nutrition therapy has been marked by controversy. Nonetheless, recent findings have pointed out to the important role of the nutrition status and of some specific nutrients on the outcome of these patients.

SUMMARY

We report the latest findings on nutrition care of patients with end-stage liver disease on the waiting list for liver transplantation such as the impact of the nutritional status on outcome, probiotic and branched-chain amino acid supplementation, as well as the use of immunomodulating formula. Another important strategy that has been shown to improve these patients' nutritional care is the offering of nocturnal meals and micronutrient supplementation.

Plasma levels of trace elements have an implication on interferon treatment of children with chronic hepatitis B infection

This study evaluated the plasma levels of trace elements in children with chronic hepatitis B virus (HBV) infection and assessed whether they can be a factor that affects the response to interferon alpha (IFN-alpha) treatment. The study included 35 cases (ten girls, 25 boys) aged 3-13 years with chronic HBV infection and the control group. Plasma levels of copper (Cu), manganese (Mn), molybdenum (Mo), selenium (Se), and zinc (Zn) were measured before IFN-alpha treatment and biochemical, virological, and histopathologic response to treatment were assessed. Children were followed for at least 15 months. Although plasma Cu levels showed no difference between the groups, Mn, Mo, Se, and Zn levels were significantly lower in the study group before treatment. Fourteen cases (40%) showed biochemical response; 17 (48.6%) showed virological response; 16 (47.6%) showed histopathologic response, and ten (28.6%) showed response according to all three parameters. Plasma Cu and Mn levels of patients with triple response showed no difference; but Mo, Se, and Zn levels were significantly lower (p < 0.001) in the study group. No difference was observed between responders and nonresponders (p > 0.05). Plasma levels of Mn, Mo, Se, and Zn are lower in children with chronic HBV infection compared to healthy children. The pretreatment levels of these elements did not show difference between responders and nonresponders to IFN-alpha.

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.

An iron-based beverage, HydroFerrate fluid (MRN-100), alleviates oxidative stress in murine lymphocytes in vitro

Background

Several studies have examined the correlation between iron oxidation and H₂O₂ degradation. The present study was carried out to examine the protective effects of MRN-100 against stress-induced apoptosis in murine splenic cells in vitro. MRN-100, or HydroFerrate fluid, is an iron-based beverage composed of bivalent and trivalent ferrates.

Methods

Splenic lymphocytes from mice were cultured in the presence or absence of MRN-100 for 2 hrs and were subsequently exposed to hydrogen peroxide (H₂O₂) at a concentration of 25 μM for 14 hrs. Percent cell death was examined by flow cytometry and trypan blue exclusion. The effect of MRN-100 on Bcl-2 and Bax protein levels was determined by Western blot.

Results

Results show, as expected, that culture of splenic cells with H₂O₂ alone results in a significant increase in cell death (apoptosis) as compared to control (CM) cells. In contrast, pre-treatment of cells with MRN-100 followed by H₂O₂ treatment results in significantly reduced levels of apoptosis.

In addition, MRN-100 partially prevents H₂O₂-induced down-regulation of the anti-apoptotic molecule Bcl-2 and upregulation of the pro-apoptotic molecule Bax.

Conclusion

Our findings suggest that MRN-100 may offer a protective effect against oxidative stress-induced apoptosis in lymphocytes.

Zinc supplementation prevents the increase of transaminase in chronic hepatitis C patients during combination therapy with pegylated interferon alpha-2b and ribavirin

We investigated the effects of zinc supplementation on clinical observations in chronic hepatitis C patients receiving pegylated interferon (PEG-IFN) alpha-2b plus ribavirin combination therapy. Patients were randomly allocated to receive 150 mg polaprezinc (zinc group, n=11) or no supplement (control group, n=12) daily in addition to PEG-IFN alpha-2b plus ribavirin therapy and 300 mg vitamin E and 600 mg vitamin C supplementation daily for 48 wk. Among the patients who continued treatment, the serum alanine aminotransferase (ALT) level at 12 wk in the zinc group was significantly lower than that in the control group. All patients in the zinc group (9/9) and 67% (8/12) of the control patients at 24 wk, and all patients in the zinc group (7/7) and 60% (6/10) of the control patients at 48 wk showed a decrease in serum ALT levels to within the normal range (7-44 U/L). HCV RNA disappeared in all patients (7/7) in the zinc group and in 8 of 10 control patients at 48 wk. Polaprezinc supplementation decreased plasma thiobarbituric acid reactive substances and prevented the decrease of polyunsaturated fatty acids of erythrocyte membrane phospholipids. No significant differences were observed in the dosage of medicines or other clinical data during the treatment. These observations indicate that polaprezinc supplementation may have induced some antioxidative functions in the liver which resulted in reduced hepatocyte injury during PEG-IFN alpha-2b plus ribavirin therapy.

Zinc and the liver: an active interaction

Zinc is an essential trace element, exerting important antioxidant, anti-inflammatory, and antiapoptotic effects. It affects growth and development and participates in processes such as aging and cancer induction. The liver is important for the regulation of zinc homeostasis, while zinc is necessary for proper liver function. Decreased zinc levels have been implicated in both acute and chronic liver disease states, and zinc deficiency has been implicated in the pathogenesis of liver diseases. Zinc supplementation offers protection in experimental animal models of acute and chronic liver injury, but these hepatoprotective properties have not been fully elucidated. In the present review, data on zinc homeostasis, its implication in the pathogenesis of liver diseases, and its effect on acute and chronic liver diseases are presented. It is concluded that zinc could protect against liver diseases, although up to now the underlying pathophysiology of zinc and liver interactions have not been defined.

Oxidative-inflammatory damage in cirrhosis: effect of vitamin E and a fermented papaya preparation

BACKGROUND AND AIM

Oxidative DNA damage occurs as an early event in hepatitis C virus (HCV) infection and is an indication of the potential for carcinogenesis. The aim of this study was to test a novel antioxidant/immunomodulator in patients with HCV-related cirrhosis.

METHODS

The study group consisted of 50 patients with HCV-related cirrhosis with transaminase values less than twofold increased (alanine aminotransferase [ALT] < 80 IU/L). Patients underwent a standardized food-vitamin composition assessment and were assessed for dietary intake, nutritional status and iron level. Patients were randomly allocated into two groups and then given either alpha-tocopherol 900 IU/day or 9 g/day of a fermented papaya preparation (FPP, Immun-Age, Osato Research Institute, Gifu, Japan) at bedtime for 6 months. Ten healthy subjects served as controls. Patients were checked monthly for: routine tests, redox status (reduced glutathione, glutathione peroxidase, oxidized glutathione, malondialdehyde), plasma alpha-tocopherol, 8-hydroxy-deoxy-guanidine (8-OHdG) level in circulating leukocyte DNA and serum levels of cytokines.

RESULTS

Patients with cirrhosis showed a significant imbalance of redox status (low antioxidants/high oxidative stress markers) (P < 0.005 vs controls). Neither treatment regimen affected transaminases as a whole. However, vitamin E supplementation almost normalized ALT only in the limited vitamin-E-deficient subgroup. A significant improvement of redox status was obtained by both regimens. However, only FPP significantly decreased 8-OHdG and the improvement of cytokine balance with FPP was significantly better than with vitamin E treatment (P < 0.05).

CONCLUSIONS

Although the present data seem to suggest a potential supportive role of antioxidants/immunomodulators as FPP in HCV patients, more studies are needed to substantiate their effect on the natural history of the disease.

Zinc L-carnosine protects against mucosal injury in portal hypertensive gastropathy through induction of heat shock protein 72

BACKGROUND AND AIMS

Increased susceptibility to gastric mucosal injury is observed in portal hypertensive gastropathy (PHG). In this study, the effects of zinc L-carnosine, an anti-ulcer drug, were evaluated on expression of heat shock protein (hsp) 72 and cytoprotection in gastric mucosa in a rat model of PHG.

METHODS

Portal hypertensive gastropathy with liver cirrhosis was induced by bile duct ligation for 4 weeks in male Sprague-Dawley rats. Expression of gastric mucosal hsp72 was evaluated by Western blotting at 6 h after intragastric administration of L-carnosine, zinc sulfate, or zinc L-carnosine. Blood was also collected for determination of serum zinc level. Mucosal protective abilities against hydrochloric acid (HCl) (0.6N) followed by pretreatment with L-carnosine, zinc sulfate or zinc L-carnosine were also studied.

RESULTS

L-carnosine, zinc sulfate, and zinc L-carnosine induced hsp72 in gastric mucosa of rats with bile duct ligation. Zinc sulfate and zinc L-carnosine suppressed HCl-induced mucosal injury. However, L-carnosine could not suppress HCl-induced mucosal injury. Serum zinc levels were significantly elevated after zinc L-carnosine administration. Furthermore, pretreatment with zinc L-carnosine (30-300 mg/kg) increased the expression of hsp72 in gastric mucosa and prevented HCl-induced mucosal injury in rats with bile duct ligation in a dose-dependent manner.

CONCLUSIONS

Zinc derivatives, especially zinc L-carnosine, protected portal hypertensive gastric mucosa with increased hsp72 expression in cirrhotic rats. It is postulated that zinc L-carnosine may be beneficial to the mucosal protection in PHG as a 'chaperone inducer'.

Heat shock protein 27 expression in patients with chronic liver damage

The aim of this study was to evaluate a possible relationship between lymphomonocyte expression of heat shock proteins (HSP) 60/27 and plasma levels of pro-inflammatory cytokines (tumor necrosis factor-alpha and interleukin-6) and markers of antioxidant/oxidative status [glutathione (GSH), alpha glutathione-S-transferase activity (alpha GST), malonyldialdeyde (MDA), 4-hydroxinonenal (4-HNE), and S-nitrosothiols (S-NO)] in patients with chronic liver diseases. Entered into the study were 47 subjects: 10 healthy controls, 16 patients with HCV-related chronic hepatitis (CH), and 16 patients with HCV-related and 5 with alcohol-related liver cirrhosis (10 Child A and 11 Child B+C). HSP60 was clearly expressed only in 5% of patients and lowly in the control group. HSP27 was clearly expressed in 46.7% of CH and 71.4% of cirrhotic patients but was lowly present in healthy subjects. A significant difference was found between patients with a low expression of HSP27 (negative patients) and those with a high HSP27 expression (positive patients) of plasma levels both of antioxidants (GSH, p < 0.05), and of markers of enhanced production of free radicals and cytokines (alpha GST, TNF-alpha and IL-6, p < 0.05; MDA, 4-HNE and S-NO, p < 0.01) as well as for alcohol use and degree of liver impairment. The present data are the first showing that, particularly in conditions of enhanced oxidative stress, lymphomonocytes from liver disease patients present an increased expression of HSP27.

Resistance of Erythrocytes to Lipid Peroxidation in Cirrhotic Rats

BACKGROUND

The aim of the present study was to investigate erythrocyte prooxidant-antioxidant balance in relation to liver and plasma lipid peroxidation in thioacetamide (TAA)-induced liver cirrhosis in rats.

METHODS

Liver cirrhosis was produced by the administration of TAA (0.3 g/L of tap water) for a period of 3 months in rats. Serum, liver and erythrocyte lipid peroxide levels as well as liver glutathione (GSH) levels and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were determined in cirrhotic rats.

RESULTS

Hepatic cirrhosis was assessed by biochemical and histopathological findings. Serum alanine transaminase (ALT) and aspartate transaminase (AST) activities and malondialdehyde (MDA) levels increased in cirrhotic rats. This treatment caused increased MDA and diene conjugate (DC) levels as well as decreased GSH levels and GSH-Px activities in the liver of cirrhotic rats. In these conditions, no significant changes in erythrocyte cholesterol, phospholipid levels as well as endogenous DC, and GSH levels and spontaneous hemolysis values were observed in erythrocytes of rats with TAA-induced liver cirrhosis. However, H(2)O(2)-induced MDA levels were detected to decrease significantly in erythrocytes of cirrhotic rats.

CONCLUSIONS

Our results indicate that erythrocytes of TAA-induced cirrhotic rats have a resistance against peroxidative stress in contrast to the findings in plasma and liver.

Blood micronutrient, oxidative stress, and viral load in patients with chronic hepatitis C

AIM: To assess the extent of micronutrient and oxidative stress in blood and to examine their linkages with viral loads in chronic hepatitis C patients.

METHODS: Hepatitis C virus (HCV)-RNA levels were quantified in the serum from 37 previously untreated patients with chronic hepatitis C. The plasma and erythrocyte micronutrients (zinc, selenium, copper, and iron) were estimated, and malondialdehyde (MDA) contents were determined as a marker to detect oxidative stress. Antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione reductase (GR) activities in blood were also measured. The control group contained 31 healthy volunteers.

RESULTS: The contents of zinc (Zn), and selenium (Se) in plasma and erythrocytes were significantly lower in hepatitis C patients than in the controls. On the contrary, copper (Cu) levels were significantly higher. Furthermore, plasma and erythrocyte MDA levels, and the SOD and GR activities in erythrocytes significantly increased in hepatitis C patients compared to the controls. However, the plasma GPX activity in patients was markedly lower. Plasma Se (r = -0.730, P < 0.05), Cu (r = 0.635), and GPX (r = -0.675) demonstrated correlations with HCV-RNA loads. Significant correlation coefficients were also observed between HCV-RNA levels and erythrocyte Zn (r = -0.403), Se (r = -0.544), Cu (r = 0.701) and MDA (r = 0.629) and GR (r = 0.441).

CONCLUSION: The levels of Zn, Se, Cu, and oxidative stress (MDA), as well as related anti-oxidative enzymes (GR and GPX) in blood have important impact on the viral factors in chronic hepatitis C. The distribution of these parameters might be significant biomarkers for HCV.

The effect of zinc supplementation on the treatment of chronic hepatitis C patients with interferon and ribavirin

OBJECTIVES

To evaluate the effects of zinc supplementation on serum zinc and copper levels, and the severity of adverse reactions and virologic responses in chronic hepatitis C patients undergoing interferon (IFN)/ribavirin therapy.

DESIGN AND METHODS

Forty subjects were randomly assigned to receive IFN-alpha-2a/ribavirin with or without zinc gluconate for 24 weeks, then a period of 6 months for follow-up. Twenty healthy controls were also enrolled in the study. Blood samples were collected at different time points during therapy and at 6 months after the completion of therapy and were analyzed for zinc and copper levels. The adverse reactions and the virologic responses were also examined accordingly.

RESULTS

Serum zinc levels were significantly lower in chronic hepatitis C patients than in healthy controls and further depressed by IFN/ribavirin treatment. However, serum zinc levels in patients were remediable by zinc supplements. No apparent difference was seen in virologic responses between subjects with or without zinc supplements, but certain adverse side effects associated with the zinc therapy were significantly decreased.

CONCLUSIONS

Zinc supplementation may be a complementary therapy in chronic hepatitis C patients to increase the tolerance to IFN-alpha-2a and ribavirin.

Effects of selenium on peripheral blood mononuclear cell membrane fluidity, interleukin-2 production and interleukin-2 receptor expression in patients with chronic hepatitis

AIM: To study the effect of selenium on peripheral blood mononuclear cell (PBMC) membrane fluidity and immune function in patients with chronic hepatitis.

METHODS: PBMCs were pretreated with selenium (1.156 × 10^-7 mol/L) for 6 h in vitro or extracted directly from patients after administration of selenium-yeast continuously for 8-12 wk (200 μg/d), and then exposed to Con-A for 48 h. The membrane fluidity, interleukin-2 (IL-2) production and interleukin-2 receptor (IL-2R) expression in PBMCs and malondialdehyde (MDA) concentration in medium and lipid peroxide (LPO) in plasma were determined.

RESULTS: The PBMC membrane fluidity, IL-2 production and IL-2R expression in patients with chronic hepatitis were significantly lower than those in healthy blood donators (particle adhesive degree R, 0.17 ± 0.01 vs 0.14 ± 0.01, P < 0.01; IL-2, 40.26 ± 9.55 vs 72.96 ± 11.36, P < 0.01; IL-2R, 31.05 ± 5.09 vs 60.58 ± 10.56, P < 0.01), and the MDA concentration in medium in patients with chronic hepatitis was significantly higher than that in healthy blood donators (1.44 ± 0.08 vs 0.93 ± 0.08, P < 0.01). Both in vitro and in vivo administration of selenium could reverse the above parameters.

CONCLUSION: Supplement of selenium can suppress lipid peroxidation, and improve PBMC membrane fluidity and immune function in patients with chronic hepatitis.

Low birth weight: a possible risk factor also for liver diseases in adult life?

Birth weight is a popular topic, because it is precisely recorded, a major determinant of infant survival, associated with infant mortality, and health outcomes later in life. Low birth weight (LBW) is a predisposing factor for metabolic abnormalities such as atherosclerosis, renal disease, non-insulin diabetes mellitus, asthma, low IQ, hypertension, obesity, psychological distress. They have all been reported to be more common among those who were small at birth. Due to lack of studies suggesting a linkage between LBW and diseases of liver; evidences, which support the hypothesis on the creation of a link between LBW, an indicator of unfavourable intrauterine environment, and liver diseases emerging in the adult life, and possible direct associations of LBW with liver diseases, e.g., hepatitis, non-alcoholic fatty liver disease, cirrhosis, hepatoblastoma, or hepatocellular carcinoma were discussed. The associations between LBW and hepatitis vaccination as well as paediatric parental nutrition were also noted.

Comparison of the serum selenium content of healthy adults living in the Antwerp region (Belgium) with recent literature data

Graphite furnace atomic absorption spectrometry, after improved matrix modification and using Zeeman background correction, was used to measure the serum selenium content of healthy adults living in the Antwerp region (Belgium). The mean serum concentration of 13 men and 13 women, sampled once a month during 1 year, was 84.3 +/- 9.4ng/ml with a broad range of 51.4-121.7 ng/ml. The intra-individual variation was remarkably high. Recent literature on selenium concentrations is reviewed and values are tabulated, with limitation to healthy adults and European countries. The mean serum selenium concentration measured corresponded well to older literature data for Belgium. The obtained values were found to be in the medium range compared with the literature data for other European countries.

Oxidative stress in viral and alcoholic hepatitis

Liver damage ranges from acute hepatitis to hepatocellular carcinoma, through apoptosis, necrosis, inflammation, immune response, fibrosis, ischemia, altered gene expression and regeneration, all processes that involve hepatocyte, Kupffer, stellate, and endothelial cells. Reactive oxygen and nitrogen species (ROS, RNS) play a crucial role in the induction and in the progression of liver disease, independently from its etiology. They are involved in the transcription and activation of a large series of cytokines and growth factors that, in turn, can contribute to further production of ROS and RNS. The main sources of free radicals are represented by hepatocyte mitochondria and cytochrome p450 enzymes, by endotoxin-activated macrophages (Kupffer cells), and by neutrophils. The consequent alteration of cellular redox state is potentiated by the correlated decrease of antioxidant and energetic reserves. Indices of free radical-mediated damage, such as the increase of malondialdehyde, 4-hydroxynonenal, protein-adducts, peroxynitrite, nitrotyrosine, etc., and/or decrease of glutathione, vitamin E, vitamin C, selenium, etc., have been documented in patients with viral or alcoholic liver disease. These markers may contribute to the monitoring the degree of liver damage, the response to antiviral therapies and to the design of new therapeutic strategies. In fact, increasing attention is now paid to a possible "redox gene therapy." By enhancing the antioxidant ability of hepatocytes, through transgene vectors, one could counteract oxidative/nitrosative stress and, in this way, contribute to blocking the progression of liver disease.