Oxidative stress in chronic hepatitis C: not just a feature of late stage disease

Insights into the Management of Chronic Hepatitis in Children-From Oxidative Stress to Antioxidant Therapy

Recent research has generated awareness of the existence of various pathophysiological pathways that contribute to the development of chronic diseases; thus, pro-oxidative factors have been accepted as significant contributors to the emergence of a wide range of diseases, from inflammatory to malignant. Redox homeostasis is especially crucial in liver pathology, as disturbances at this level have been linked to a variety of chronic diseases. Hepatitis is an umbrella term used to describe liver inflammation, which is the foundation of this disease regardless of its cause. Chronic hepatitis produces both oxidative stress generated by hepatocyte inflammation and viral inoculation. The majority of hepatitis in children is caused by a virus, and current studies reveal that 60-80% of cases become chronic, with many young patients still at risk of advancing liver damage. This review intends to emphasize the relevance of understanding these pathological redox pathways, as well as the need to update therapeutic strategies in chronic liver pathology, considering the beneficial effects of antioxidants.

Yellow fever virus infection in human hepatocyte cells triggers an imbalance in redox homeostasis with increased reactive oxygen species production, oxidative stress, and decreased antioxidant enzymes

Yellow fever (YF) presents a wide spectrum of severity, with clinical manifestations in humans ranging from febrile and self-limited to fatal cases. Although YF is an old disease for which an effective and safe vaccine exists, little is known about the viral- and host-specific mechanisms that contribute to liver pathology. Several studies have demonstrated that oxidative stress triggered by viral infections contributes to pathogenesis. We evaluated whether yellow fever virus (YFV), when infecting human hepatocytes cells, could trigger an imbalance in redox homeostasis, culminating in oxidative stress. YFV infection resulted in a significant increase in reactive oxygen species (ROS) levels from 2 to 4 days post infection (dpi). When measuring oxidative parameters at 4 dpi, YFV infection caused oxidative damage to lipids, proteins, and DNA, evidenced by an increase in lipid peroxidation/8-isoprostane, carbonyl protein, and 8-hydroxy-2'-deoxyguanosine, respectively. Furthermore, there was a significant reduction in the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx), in addition to a reduction in the ratio of reduced to oxidized glutathione (GSH/GSSG), indicating a pro-oxidant environment. However, no changes were observed in the enzymatic activity of the enzyme catalase (CAT) or in the gene expression of SOD isoforms (1/2/3), CAT, or GPx. Therefore, our results show that YFV infection generates an imbalance in redox homeostasis, with the overproduction of ROS and depletion of antioxidant enzymes, which induces oxidative damage to cellular constituents. Moreover, as it has been demonstrated that oxidative stress is a conspicuous event in YFV infection, therapeutic strategies based on antioxidant biopharmaceuticals may be new targets for the treatment of YF.

Colored wheat and derived products: key to global nutritional security

Ensuring food and nutritional security of fast-growing population will pose a huge challenge in future. An estimated one-half population who does not go hungry, nonetheless suffers the debilitating effects of unhealthy diets. In view of the nutritional awareness, when the major wheat breeding programs have started shifting to quality, instead of quantity in wheat, the colored wheats give a novel twist of targeting the malnutrition by enhancing the antioxidants such as anthocyanin, carotenoids, flavonoids, polyphenols etc. Moreover, changing consumer demands have picked the trend to prefer a nutritionally balanced diet over the conventional high energy diets and thus, colored wheat has opened up a hidden avenue for providing additional value to the wheat-based products. Besides providing nutrition, these pigments have the potential to replace the synthetic dyes and food colorants prevalent in the market. The review summarizes the genetics and biochemistry of the pigments of colored wheat along with their product development, nutritional status and consumer preference. The review also sheds light on the environmental effect on color accumulation and the effect of increased colorants on other quality traits of wheat.

Therapeutic mechanisms and beneficial effects of non-antidiabetic drugs in chronic liver diseases

The global burden of chronic liver disease (CLD) is substantial. Due to the limited indication of and accessibility to antiviral therapy in viral hepatitis and lack of effective pharmacological treatment in nonalcoholic fatty liver disease, the beneficial effects of antidiabetics and non-antidiabetics in clinical practice have been continuously investigated in patients with CLD. In this narrative review, we focused on non-antidiabetic drugs, including ursodeoxycholic acid, silymarin, dimethyl4,4'-dimethoxy-5,6,5',6'-dimethylenedixoybiphenyl-2,2'-dicarboxylate, L-ornithine L-aspartate, branched chain amino acids, statin, probiotics, vitamin E, and aspirin, and summarized their beneficial effects in CLD. Based on the antioxidant, anti-inflammatory properties, and regulatory functions in glucose or lipid metabolism, several non-antidiabetic drugs have shown beneficial effects in improving liver histology, aminotransferase level, and metabolic parameters and reducing risks of hepatocellular carcinoma and mortality, without significant safety concerns, in patients with CLD. Although the effect as the centerpiece management in patients with CLD is not robust, the use of these non-antidiabetic drugs might be potentially beneficial as an adjuvant or combined treatment strategy.

Role of Selenium in Viral Infections with a Major Focus on SARS-CoV-2

Viral infections have afflicted human health and despite great advancements in scientific knowledge and technologies, continue to affect our society today. The current coronavirus (COVID-19) pandemic has put a spotlight on the need to review the evidence on the impact of nutritional strategies to maintain a healthy immune system, particularly in instances where there are limited therapeutic treatments. Selenium, an essential trace element in humans, has a long history of lowering the occurrence and severity of viral infections. Much of the benefits derived from selenium are due to its incorporation into selenocysteine, an important component of proteins known as selenoproteins. Viral infections are associated with an increase in reactive oxygen species and may result in oxidative stress. Studies suggest that selenium deficiency alters immune response and viral infection by increasing oxidative stress and the rate of mutations in the viral genome, leading to an increase in pathogenicity and damage to the host. This review examines viral infections, including the novel SARS-CoV-2, in the context of selenium, in order to inform potential nutritional strategies to maintain a healthy immune system.

Thiol-disulphide balance and total oxidant-antioxidant status in patients with chronic hepatitis C

OBJECTIVE

To assess the dynamic thiol/disulphide homeostasis (DTDH) and total oxidant/antioxidant status in patients with hepatitis C virus (HCV) infection and to evaluate their association with HCV-RNA levels.

METHODS

Levels of serum total thiol (TT), native thiol (NT), disulphide (DS), total oxidant status (TOS), total antioxidant status (TAS) and oxidative stress index (OSI) as oxidative stress markers were determined in 162 individuals, including 74 patients with HCV infection and 88 non-HCV controls. HCV genotypes and HCV-RNA levels of the patients were recorded.

RESULTS

The NT, TT and TAS levels and NT/TT ratio were significantly lower in the HCV group compared with the control group. On the contrary, DS, TOS and OSI levels and DS/NT and DS/TT ratios were significantly higher. Patients with high HCV RNA levels (> 650 000 IU/mL) had higher DS levels than patients with low HCV-RNA levels (<650 000 IU/mL). Genotype 1 was observed in 68.9% of patients with HCV. Levels of oxidative stress parameters were similar between genotype 1 and other genotypes (2, 3 and 5). No significant correlations were found between oxidative stress markers and albumin, alanine aminotransferase, aspartate aminotransferase, bilirubin and HCV-RNA levels in patients with HCV infection. A negative correlation was found only between OSI and albumin.

CONCLUSION

Our results suggest that DTDH shifts towards the DS direction because of thiol oxidation in HCV-infected patients. Furthermore, DS levels were significantly higher in patients with high HCV-RNA levels compared with patients with low HCV-RNA levels.

Potentials of Musa Species Fruits against Oxidative Stress-Induced and Diet-Linked Chronic Diseases: In Vitro and In Vivo Implications of Micronutritional Factors and Dietary Secondary Metabolite Compounds

Nutritional quality and the well-being of the body system are directly linked aspects of human survival. From the unborn foetus to adulthood, the need for sustainable access to micronutrient-rich foods is pertinent and the global consumption of banana and plantain fruits, in effect, contributes to the alleviation of the scourge of malnutrition. This review is particularly aimed at evaluating the pharmacological dimensions through the biological mechanisms of Musa fruits in the body, which represent correlations with their constituent micronutrient factors and dietary polyphenolic constituents such as minerals, vitamin members, anthocyanins, lutein, α-,β- carotenes, neoxanthins and cryptoxanthins, epi- and gallo catechins, catecholamines, 3-carboxycoumarin, β-sitosterol, monoterpenoids, with series of analytical approaches for the various identified compounds being highlighted therein. Derivative value-products from the compartments (flesh and peel) of Musa fruits are equally highlighted, bringing forth the biomedicinal and nutritional relevance, including the potentials of Musa species in dietary diversification approaches.

Urinary markers of oxidative stress respond to infection and late-life in wild chimpanzees

Oxidative stress (OS) plays a marked role in aging and results from a variety of stressors, making it a powerful measure of health and a way to examine costs associated with life history investments within and across species. However, few urinary OS markers have been examined under field conditions, particularly in primates, and their utility to non-invasively monitor the costs of acute stressors versus the long-term damage associated with aging is poorly understood. In this study, we examined variation in 5 urinary markers of oxidative damage and protection under 5 validation paradigms for 37 wild, chimpanzees living in the Kibale National Park, Uganda. We used 924 urine samples to examine responses to acute immune challenge (respiratory illness or severe wounding), as well as mixed-longitudinal and intra-individual variation with age. DNA damage (8-OHdG) correlated positively with all other markers of damage (F-isoprostanes, MDA-TBARS, and neopterin) but did not correlate with protection (total antioxidant capacity). Within individuals, all markers of damage responded to at least one if not both types of acute infection. While OS is expected to increase with age, this was not generally true in chimpanzees. However, significant changes in oxidative damage were detected within past-prime individuals and those close to death. Our results indicate that OS can be measured using field-collected urine and integrates short- and long-term aspects of health. They further suggest that more data are needed from long-lived, wild animals to illuminate if common age-related increases in inflammation and OS damage are typical or recently aberrant in humans.

Direct-acting antivirals restore systemic redox homeostasis in chronic HCV patients

Chronic hepatitis C therapy has completely changed in the last years due to the availability of direct-acting antivirals (DAAs). Removing the virus may be not enough since chronic infection deeply modifies immune system and cellular metabolism along decades of inflammation. Oxidative stress plays a significant role in maintaining systemic inflammation during chronic HCV infection. Other than removing the virus, effective therapy could counteract oxidative stress. This study investigated the impact of DAA treatment on circulating markers of oxidative stress and antioxidant defence in a cohort of patients affected by chronic hepatitis C. To this, an observational study on 196 patients who started therapy with DAA for HCV-related hepatitis was performed. Patients were assessed at baseline, 4 weeks after the initiation of therapy (4wks), at the end of treatment (EoT), and 12 weeks after the EoT (SVR12). Circulating oxidative stress was determined by measuring serum hydroxynonenal (HNE)- and malondialdehyde (MDA)-protein adducts, and 8-hydroxydeoxyguanosine (8-OHdG). Antioxidant status was evaluated by measuring the enzymatic activity and mRNA expression of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in peripheral blood mononuclear cells. We observed a reduction of serum 8-OHdG at 4wks, while the circulating level of both HNE- and MDA-protein adducts diminished at EoT; all these markers persisted low at SVR12. On the other side, we reported an increase in the enzymatic activity of all the antioxidant enzymes in PBMC at EoT and SVR12. Taking into account circulating 8-OHdG and antioxidant enzyme activities, patients with high fibrosis stage were those that had the most benefit from DAA therapy. To conclude, this study indicates that treatment with DAAs improves the circulating redox status of patients affected by chronic hepatitis C. This positive impact of DAA therapy may be related to its effectiveness on cutting down viremia and pro-inflammatory markers.

Bok-choy promotes growth performance, lipid metabolism and related gene expression in Syrian golden hamsters fed with a high-fat diet

Broadly, bok-choy is known for its potential benefits as part of a human diet. However, the effects and deeper investigations of bok-choy on human health are still insufficient. This study aimed to investigate the beneficial effects of two cultivars of bok-choy, 'Suzhouqing' (green cultivar) and 'Ziluolan' (purple cultivar), on growth performance, lipid metabolism and related gene expressions in Syrian golden hamsters. Fifty six male Syrian golden hamsters (6-months-old) were randomly assigned into 6 groups: normal diet (A), high-fat diet (B), high-fat diet + 5% 'Suzhouqing' (C), high-fat diet + 7% 'Suzhouqing' (D), high-fat diet + 5% 'Ziluolan' (E), and high-fat diet + 7% 'Ziluolan' (F), fed for 56 consecutive days. On day 0, 28 and 56, blood and liver samples were collected to examine the lipid profile, liver enzymes, histomorphology and related gene expressions. The results showed that group B had significantly increased levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase, while (P < 0.05) showed impaired levels of high-density lipoprotein cholesterol compared with group A. Group D, E and F had significantly reduced levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase, while the level of high-density lipoprotein cholesterol was significantly increased compared with group B. Remarkably, the mRNA expressions of CEBP-α, DGAT1, lipoprotein lipase (LPL), FASN and 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA) were significantly up-regulated and carnitine palmitoyl transferase 2 (CPT2), Cyp27A1 and proliferator activated receptor alpha (PPAR-α) were significantly down-regulated in group B compared with group A. However, in group D, E and F, the mRNA expression levels of CCAAT enhancer binding protein alpha, DGAT1, LPL, FASN and HMG-CoA were significantly down-regulated and CPT2, Cyp27A1 and PPAR-α were significantly up-regulated compared with group B. In conclusion, different amounts of bok-choy added to the diets incredibly improved the lipid-profile, enhanced liver enzyme activities and related gene expression. The hamsters supplemented with 7% 'Ziluolan' exhibited the best performance among all the other high-fat groups, which shows that Ziluolan could be a great alternative for the reduction of fat accumulation and conserving health.

Sex Differences, Cocaine Use, and Liver Fibrosis Among African Americans in the Miami Adult Studies on HIV Cohort

Background: HIV infection disproportionally affects African Americans. Liver disease is a major cause of non-HIV morbidity and mortality in this population. Substance abuse accelerates HIV disease and may facilitate progression of liver disease. This study investigated the relationship between sex differences and cocaine use with liver injury, characterized as hepatic fibrosis. Materials and Methods: A cross-sectional study was conducted on 544 African Americans [369 people living with HIV (PLWH) and 175 HIV seronegative] from the Miami Adult Studies on HIV (MASH) cohort. Cocaine use was determined with a validated self-reported questionnaire and confirmed with urine screen. Fasting blood was used to estimate liver fibrosis using the noninvasive fibrosis-4 (FIB-4) index. Results: Men living with HIV had 1.79 times higher odds for liver fibrosis than women living with HIV (p = 0.038). African American women had higher CD4 count (p = 0.001) and lower HIV viral load (p = 0.011) compared to African American men. Fewer women (PLWH and HIV seronegative) smoked cigarettes (p = 0.002), and fewer had hazardous or harmful alcohol use (p < 0.001) than men. Women also had higher body mass index (kg/m²) (p < 0.001) compared to men. No significant association was noted among HIV seronegative participants for liver fibrosis by sex differences or cocaine use. Among African Americans living with HIV, cocaine users were 1.68 times more likely to have liver fibrosis than cocaine nonusers (p = 0.044). Conclusions: Sex differences and cocaine use appear to affect liver disease among African Americans living with HIV pointing to the importance of identifying at-risk individuals to improve outcomes of liver disease.

Redox cell signaling and hepatic progenitor cells

Hepatic diseases are widespread in the world and organ transplantation is currently the only treatment for liver failure. New cell-based approaches have been considered, since stem cells may represent a possible source to treat liver diseases. Acute and chronic liver diseases are characterized by high production of reactive oxygen and nitrogen species, with consequent oxidative modifications of cellular macromolecules and alteration of signaling pathways, metabolism and cell cycle. Although considered harmful molecules, reactive species are involved in cell growth and differentiation processes, modulating the activity of transcription factors, which take part in stemness/proliferation. It is conceivable that redox balance may regulate the development of hepatic progenitor cells, function and survival in synchrony with metabolism during chronic liver diseases. This review aims to summarize diverse redox-sensitive signaling pathways involved in stem cell fate, highlighting the important role of hepatic progenitor cells as a possible source to treat end-stage liver disease for organ regeneration.

Redox Biology of Respiratory Viral Infections

Respiratory viruses cause infections of the upper or lower respiratory tract and they are responsible for the common cold—the most prevalent disease in the world. In many cases the common cold results in severe illness due to complications, such as fever or pneumonia. Children, old people, and immunosuppressed patients are at the highest risk and require fast diagnosis and therapeutic intervention. However, the availability and efficiencies of existing therapeutic approaches vary depending on the virus. Investigation of the pathologies that are associated with infection by respiratory viruses will be paramount for diagnosis, treatment modalities, and the development of new therapies. Changes in redox homeostasis in infected cells are one of the key events that is linked to infection with respiratory viruses and linked to inflammation and subsequent tissue damage. Our review summarizes current knowledge on changes to redox homeostasis, as induced by the different respiratory viruses.

Possible Synergistic Effects of Glutathione and C-Reactive Protein in the Progression of Liver Cirrhosis

Liver cirrhosis is often associated with increased inflammatory responses and changes of glutathione (GSH) status. The possible interactions between these two factors in mediating damages of liver function remain unclear. Here, we measured the inflammatory responses and GSH status in liver cirrhotic patients and compared them with healthy subjects. In addition, we assessed the relationship of the GSH status and levels of inflammatory markers with the severity of the disease. This was a cross-sectional study. In total, we recruited 63 liver cirrhotic patients with Child⁻Turcotte⁻Pugh class A scores, and 12 patients with class B⁻C scores, together with 110 healthy subjects. Patients with class B⁻C scores showed the highest level of high-sensitivity C-reactive protein (hs-CRP) when compared with class A patients or healthy subjects. Patients in class A group had significantly higher GSH levels when compared with class B⁻C group or healthy subjects. After adjusting for potential confounders and each other, serum hs-CRP levels showed positive association with the Child⁻Turcotte⁻Pugh scores, while GSH levels showed negative association with Child⁻Turcotte⁻Pugh scores. Interactions were found between levels of plasma GSH and serum hs-CRP (β = 0.004, p = 0.016). CRP and GSH levels, which had showed interactions, were associated with the severity of liver cirrhosis.

Oxidative stress, a trigger of hepatitis C and B virus-induced liver carcinogenesis

Virally induced liver cancer usually evolves over long periods of time in the context of a strongly oxidative microenvironment, characterized by chronic liver inflammation and regeneration processes. They ultimately lead to oncogenic mutations in many cellular signaling cascades that drive cell growth and proliferation. Oxidative stress, induced by hepatitis viruses, therefore is one of the factors that drives the neoplastic transformation process in the liver. This review summarizes current knowledge on oxidative stress and oxidative stress responses induced by human hepatitis B and C viruses. It focuses on the molecular mechanisms by which these viruses activate cellular enzymes/systems that generate or scavenge reactive oxygen species (ROS) and control cellular redox homeostasis. The impact of an altered cellular redox homeostasis on the initiation and establishment of chronic viral infection, as well as on the course and outcome of liver fibrosis and hepatocarcinogenesis will be discussed The review neither discusses reactive nitrogen species, although their metabolism is interferes with that of ROS, nor antioxidants as potential therapeutic remedies against viral infections, both subjects meriting an independent review.

Classifying oxidative stress by F2-isoprostane levels across human diseases: A meta-analysis

The notion that oxidative stress plays a role in virtually every human disease and environmental exposure has become ingrained in everyday knowledge. However, mounting evidence regarding the lack of specificity of biomarkers traditionally used as indicators of oxidative stress in human disease and exposures now necessitates re-evaluation. To prioritize these re-evaluations, published literature was comprehensively analyzed in a meta-analysis to quantitatively classify the levels of systemic oxidative damage across human disease and in response to environmental exposures.

In this meta-analysis, the F₂-isoprostane, 8-iso-PGF_2α, was specifically chosen as the representative marker of oxidative damage. To combine published values across measurement methods and specimens, the standardized mean differences (Hedges’ g) in 8-iso-PGF_2α levels between affected and control populations were calculated.

The meta-analysis resulted in a classification of oxidative damage levels as measured by 8-iso-PGF_2α across 50 human health outcomes and exposures from 242 distinct publications. Relatively small increases in 8-iso-PGF_2α levels (g<0.8) were found in the following conditions: hypertension (g=0.4), metabolic syndrome (g=0.5), asthma (g=0.4), and tobacco smoking (g=0.7). In contrast, large increases in 8-iso-PGF_2α levels were observed in pathologies of the kidney, e.g., chronic renal insufficiency (g=1.9), obstructive sleep apnoea (g=1.1), and pre-eclampsia (g=1.1), as well as respiratory tract disorders, e.g., cystic fibrosis (g=2.3).

In conclusion, we have established a quantitative classification for the level of 8-iso-PGF_2α generation in different human pathologies and exposures based on a comprehensive meta-analysis of published data. This analysis provides knowledge on the true involvement of oxidative damage across human health outcomes as well as utilizes past research to prioritize those conditions requiring further scrutiny on the mechanisms of biomarker generation.

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Oxidative damage is highly variable in human conditions as measured by F₂-isoprostanes.

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Respiratory tract and urogenital diseases have the highest F₂-isoprostanes.

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Cancer and cardiovascular diseases have surprisingly low F₂-isoprostanes.

Orange juice as dietary source of antioxidants for patients with hepatitis C under antiviral therapy

Background: HCV causes alterations in liver metabolism, resulting in biochemical and nutritional disorders. Supplementation with antioxidants has been suggested to minimize the diseases effects.

Objective: This study assessed whether orange juice, a source of citrus flavonoids and vitamin C, may contribute to the treatment of patients with chronic hepatitis C.

Design: Anthropometric, hemodynamic, dietary, and biochemical parameters, CRP and liver enzymes were measured in 43 adult patients of both genders who were diagnosed with chronic hepatitis C and were under antiviral therapy. Twenty-three patients were supplemented with orange juice for eight consecutive weeks, while 20 were enrolled as control group.

Results: Following regular use of orange juice, no alterations were found in body mass, fat, and waist circumference. The serum levels of total cholesterol, LDL-cholesterol, CRP and parameters of oxidative stress decreased in the orange juice group. Furthermore, the levels of the liver enzyme AST decreased in those who had high levels before the intervention.

Conclusion: The orange juice was a convenient food in the diet of patients due to the increase in antioxidant capacity and decreased inflammation and cholesterol in blood serum, in addition to maintaining body mass, which protect against the harmful effects caused by the chronic hepatitis C virus.​​​

Role of UDP-Glucuronosyltransferase 1A1 in the Metabolism and Pharmacokinetics of Silymarin Flavonolignans in Patients with HCV and NAFLD

Silymarin is the most commonly used herbal medicine by patients with chronic liver disease. Silymarin flavonolignans undergo rapid first-pass metabolism primarily by glucuronidation. The aims of this investigation were: (1) to determine the association of UGT1A1*28 polymorphism with the area under the plasma concentration-time curves (AUCs) for silybin A (SA) and silybin B (SB); (2) to evaluate the effect of UGT1A1*28 polymorphism on the profile of flavonolignan glucuronide conjugates found in the plasma; and (3) to investigate the role of UGT1A1 enzyme kinetics on the pharmacokinetics of SA and SB. AUCs and metabolic ratios for thirty-three patients with chronic liver disease administered oral doses of silymarin were compared between different UGT1A1*28 genotypes. The AUCs, metabolic ratios, and the profiles of major SA and SB glucuronides did not differ significantly among the three UGT1A1 genotypes. In contrast, an increase in the proportion of sulfated flavonolignan conjugates in plasma was observed in subjects with UGT1A1*28/*28 genotype compared to subjects carrying wild type alleles. Differences in SA and SB in vitro intrinsic clearance estimates for UGTIA1 correlated inversely with SA and SB exposures observed in vivo indicating a major role for UGT1A1 in silymarin metabolism. In addition, a significant difference in the metabolic ratio observed between patients with NAFLD and HCV suggests that any effect of UGT1A1 polymorphism may be obscured by a greater effect of liver disease on the pharmacokinetics of silymarin. Taken together, these results suggest the presence of the UGT1A1*28 allele does not contribute significantly to a large inter-subject variability in the pharmacokinetics of silybin A and silybin B which may obscure the ability to detect beneficial effects of silymarin in patients with liver disease.

A Study of Intravenous Administration of Vitamin C in the Treatment of Acute Herpetic Pain and Postherpetic Neuralgia

BACKGROUND

Although there are several available management strategies for treatment of both acute pain of herpes zoster (HZ) and postherpetic neuralgia (PHN), it is difficult to treat them adequately.

OBJECTIVE

The aim of this study was to evaluate the efficacy of intravenously administrated vitamin C on acute pain and its preventive effects on PHN in patients with HZ.

METHODS

Between September 2011 and May 2013 eighty-seven patients who were admitted for HZ were assessed according to age, sex, underlying diseases, duration of pain and skin lesion, dermatomal distribution, and PHN. It was a randomized controlled study, in which 87 patients were randomly allocated into the ascorbic acid group and control group. Each patient received normal saline infusion with or without 5 g of ascorbic acid on days 1, 3, and 5 then answered questionnaires that included side effects and pain severity using visual analogue scale on days 1, 2, 3, 4, and 5. After discharge, the severity of pain was obtained at out-patient clinic or by telephone on weeks 2, 4, 8, and 16.

RESULTS

There was no differences in severity of pain on patients' age, sex, underlying diseases, duration of pain and skin lesion and dermatomal distribution between two groups (p>0.05). Since 8th week, pain score in ascorbic acid treatment group was significantly lower than control group (p <0.05). The incidence of PHN was significantly lower in the treatment group compared to control group (p=0.014). The changes of overall pain score was significantly different between the two groups (p<0.05).

CONCLUSION

Intravenously administered ascorbic acid did not relieve acute HZ pain; but is effective for reducing the incidence of PHN.

Assessment of indicators of vitamin A status in non-cirrhotic chronic hepatitis C patients

Subjects with chronic liver disease are susceptible to hypovitaminosis A due to several factors. Therefore, identifying patients with vitamin deficiency and a requirement for vitamin supplementation is important. Most studies assessing vitamin A in the context of hepatic disorders are conducted using cirrhotic patients. A cross-sectional study was conducted in 43 non-cirrhotic patients with chronic hepatitis C to evaluate markers of vitamin A status represented by serum retinol, liver retinol, and serum retinol-binding protein levels. We also performed the relative dose-response test, which provides an indirect estimate of hepatic vitamin A reserves. These vitamin A indicators were assessed according to the stage of liver fibrosis using the METAVIR score and the body mass index. The sample study was predominantly composed of male subjects (63%) with mild liver fibrosis (F1). The relative dose-response test was <20% in all subjects, indicating vitamin A sufficiency. Overweight or obese patients had higher serum retinol levels than those with a normal body mass index (2.6 and 1.9 µmol/L, respectively; P<0.01). Subjects with moderate liver fibrosis (F2) showed lower levels of serum retinol (1.9 vs 2.5 µmol/L, P=0.01) and retinol-binding protein levels compared with those with mild fibrosis (F1) (46.3 vs 67.7 µg/mL, P<0.01). These results suggested an effect of being overweight on serum retinol levels. Furthermore, more advanced stages of liver fibrosis were related to a decrease in serum vitamin A levels.

GC Gene Polymorphism and Unbound Serum Retinol-Binding Protein 4 Are Related to the Risk of Insulin Resistance in Patients With Chronic Hepatitis C: A Prospective Cross-Sectional Study

Insulin resistance (IR) is found in chronic hepatitis C (CHC) more frequently than in other chronic liver diseases.Prospective cross-sectional study to evaluate a wide multitest panel to identify factors related with IR in CHC and their possible interactions.In 76 patients with CHC we performed a series of routine laboratory analysis as well as specifically designed serum biochemical tests [retinol, retinol-binding protein 4 (RBP4), 25-OH vitamin D, Vitamin E, lipopolysaccharide-binding protein (LBP), interleukin-6 (IL-6), and cystatin C]. The single nucleotide polymorphisms rs7041 and rs4588 GC-DBP (group-specific component-Vitamin D-binding protein), rs738409 PNPLA3 (patatin-like phospholipase domain containing 3), and rs12979860 IL28B (interleukin-28 B) genes were determined. Insulin sensitivity was established with the HOMA-IR and IR was diagnosed when HOMA-IR > 3. Fibrosis staging was assessed with liver biopsy or transient elastography.After backward logistic regression analysis, independent variables associated with IR were Gc1s/Gc1s DBP phenotype, that results from the homozygous carriage of the rs7041G/rs4588C haplotype (P = 0.033); low retinol/RBP4 ratio, reflecting a greater rate of unbound RBP4 (P = 0.005); older age (P = 0.01); high serum tryglicerides (P = 0.026); and advanced (F3-F4) fibrosis stage. The AUROC provided by the multivariate model was 0.950 (95% CI = 0.906-0.993).In addition to previously known ones, the Gc1s/Gc1s phenotype variant of DBP and the unbound fraction of plasma RBP4 may be considered as factors related with the incidence, and possibly the risk, of IR in CHC patients.

Retinoid and carotenoid status in serum and liver among patients at high-risk for liver cancer

Background

Approximately 2.7 million Americans are chronically infected with hepatitis C virus (HCV). HCV patients with cirrhosis form the largest group of persons at high risk for hepatocellular carcinoma (HCC). Increased oxidative stress is regarded as a major mechanism of HCV-related liver disease progression. Deficiencies in retinoid and carotenoid antioxidants may represent a major modifiable risk factor for disease progression. This study aims to identify key predictors of serum antioxidant levels in patients with HCV, to examine the relationship between retinoid/carotenoid concentrations in serum and hepatic tissue, to quantify the association between systemic measures of oxidative stress and antioxidant status, and to examine the relationship between retinoids and stellate cell activation.

Methods

Patients undergoing liver biopsy (n = 69) provided fasting blood, fresh tissue, urine and completed a diet history questionnaire. Serum and questionnaire data from healthy volunteers (n = 11), normal liver tissue from public repositories and patients without liver disease (n = 11) were also collected. Urinary isoprostanes, serum and tissue retinoid concentrations were obtained by UHPLC-MS-MS. Immunohistochemistry for αSMA was performed on FFPE sections and subsequently quantified via digital image analysis. Associations between urinary isoprostanes, αSMA levels, and retinoids were assessed using Spearman correlation coefficients and non-parametric tests were utilized to test differences among disease severity groups.

Results

There was a significant inverse association between serum retinol, lycopene, and RBP4 concentrations with fibrosis stage. Serum β-carotene and lycopene were strongly associated with their respective tissue concentrations. There was a weak downward trend of tissue retinyl palmitate with increasing fibrosis stage. Tissue retinyl palmitate was inversely and significantly correlated with hepatic αSMA expression, a marker for hepatic stellate cell activation (r = −0.31, P < 0.02). Urinary isoprostanes levels were inversely correlated with serum retinol, β-carotene, and RBP4.

Conclusions

A decrease in serum retinol, β-carotene, and RBP4 is associated with early stage HCV. Retinoid and carotenoid levels decline as disease progresses, and our data suggest that this decline occurs early in the disease process, even before fibrosis is apparent. Measures of oxidative stress are associated with fibrosis stage and concurrent antioxidant depletion. Vitamin A loss is accompanied by stellate cell activation in hepatic tissue.

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-016-0432-5) contains supplementary material, which is available to authorized users.

Manganese superoxide dismutase and oxidative stress modulation

Oxidative stress is characterized by imbalanced reactive oxygen species (ROS) production and antioxidant defenses. Two main antioxidant systems exist. The nonenzymatic system relies on molecules to directly quench ROS and the enzymatic system is composed of specific enzymes that detoxify ROS. Among the latter, the superoxide dismutase (SOD) family is important in oxidative stress modulation. Of these, manganese-dependent SOD (MnSOD) plays a major role due to its mitochondrial location, i.e., the main site of superoxide (O(2)(·-)) production. As such, extensive research has focused on its capacity to modulate oxidative stress. Early data demonstrated the relevance of MnSOD as an O(2)(·-) scavenger. More recent research has, however, identified a prominent role for MnSOD in carcinogenesis. In addition, SOD downregulation appears associated with health risk in heart and brain. A single nucleotide polymorphism which alters the mitochondria signaling sequence for the cytosolic MnSOD form has been identified. Transport into the mitochondria was differentially affected by allelic presence and a new chapter in MnSOD research thus begun. As a result, an ever-increasing number of diseases appear associated with this allelic variation including metabolic and cardiovascular disease. Although diet and exercise upregulate MnSOD, the relationship between environmental and genetic factors remains unclear.

Oxidative stress and antioxidant status in patients with autoimmune liver diseases

OBJECTIVE

To estimate oxidative stress and antioxidant components during different stages of autoimmune liver diseases and assess their possible implication on disease progression.

METHODS

We determined several markers of oxidative injury (isoprostane, aldehydes, protein carbonyls, 3-nitrotyrosine, and myeloperoxidase) and antioxidant components (glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase) in whole blood, serum, and urine in 49 patients with autoimmune cholestatic liver diseases (AC) and 36 patients with autoimmune hepatitis (AIH) and healthy subjects matched for sex and age.

RESULTS

Both AC and AIH patients had increased levels of all lipid and protein oxidative injury products and significantly decreased whole blood glutathione levels compared to controls. AIH patients had significantly higher levels of aldehydes and glutathione peroxidase activity and significantly lower protein carbonyl levels compared to AC patients. Protein carbonyl and isoprostane levels increased and glutathione levels decreased gradually with progression from mild fibrosis to severe fibrosis and cirrhosis in both AC and AIH patients. In addition, both cirrhotic AC and AIH patients had significantly higher protein carbonyls compared to non-cirrhotics.

DISCUSSION

We provide novel findings in support of a major contribution of oxidant/antioxidant imbalance in the progression of liver injury in AC and AIH.

Estimation of copper and iron burden in biological samples of various stages of hepatitis C and liver cirrhosis patients

There is accumulative evidence that the metabolism of iron (Fe) and copper (Cu) is altered in human due to infections, indicating that both elements have roles in pathogenesis and progress of viral diseases. In the present study, the correlation of Cu and Fe was evaluate in biological samples (serum and scalp hair) of hepatitis C (hepatitis C virus (HCV)) patients of both genders at different stages. For comparative study, the scalp hair and serum samples of healthy individuals of same age group (30-50 years) and socioeconomic status were collected. The biological samples were analyzed for Fe and Cu by atomic absorption spectroscopy after microwave-assisted acid digestion. The validity and accuracy of methodology were checked by certified reference materials of same matrixes. The levels of Cu and Fe in biological samples were enhanced in hepatic disorder patients, including acute (after diagnosis test, anti-HCV sero-positive) hepatic fibrosis and liver cirrhosis as compared to healthy referents. The difference was significant (p < 0.01) in the case of liver cirrhotic patients. It was observed that the data of Cu and Fe in referents and patients of both genders had normal distributions. The inter-elemental correlation (r) among Cu vs Fe in serum and scalp hair samples of referents and patients were not significant in both genders (p > 0.1) except in the first stage of HCV (p < 0.1). It was concluded that the increase of Cu and Fe content in human body seems to contribute to the development of cirrhosis in patients with viral hepatitis C.

Regulation of the hepatitis C virus RNA replicase by endogenous lipid peroxidation

Although oxidative tissue injury often accompanies viral infection, there is little understanding of how it influences virus replication. We show that multiple hepatitis C virus (HCV) genotypes are exquisitely sensitive to oxidative membrane damage, a property distinguishing them from other pathogenic RNA viruses. Lipid peroxidation, regulated in part through sphingosine kinase 2, severely restricts HCV replication in Huh-7 cells and primary human hepatoblasts. Endogenous oxidative membrane damage lowers the 50% effective concentration of direct-acting antivirals, suggesting critical regulation of the conformation of the NS3/4A protease and NS5B polymerase, membrane-bound HCV replicase components. Resistance to lipid peroxidation maps genetically to trans-membrane and membrane-proximal residues within these proteins, and is essential for robust replication in cell culture, as exemplified by the atypical JFH1 strain. Thus, the typical, wild-type HCV replicase is uniquely regulated by lipid peroxidation, providing a novel mechanism for attenuating replication in stressed tissue and possibly facilitating long-term viral persistence.

RNA Viruses: ROS-Mediated Cell Death

Reactive oxygen species (ROS) are well known for being both beneficial and deleterious. The main thrust of this review is to investigate the role of ROS in ribonucleic acid (RNA) virus pathogenesis. Much evidences has accumulated over the past decade, suggesting that patients infected with RNA viruses are under chronic oxidative stress. Changes to the body's antioxidant defense system, in relation to SOD, ascorbic acid, selenium, carotenoids, and glutathione, have been reported in various tissues of RNA-virus infected patients. This review focuses on RNA viruses and retroviruses, giving particular attention to the human influenza virus, Hepatitis c virus (HCV), human immunodeficiency virus (HIV), and the aquatic Betanodavirus. Oxidative stress via RNA virus infections can contribute to several aspects of viral disease pathogenesis including apoptosis, loss of immune function, viral replication, inflammatory response, and loss of body weight. We focus on how ROS production is correlated with host cell death. Moreover, ROS may play an important role as a signal molecule in the regulation of viral replication and organelle function, potentially providing new insights in the prevention and treatment of RNA viruses and retrovirus infections.

Effect of high dose vitamin C on Epstein-Barr viral infection

Background Many natural compounds were tested for the ability to suppress viral replication. The present manuscript details an analysis of high dose vitamin C therapy on patients with EBV infection. Material and Methods The data were obtained from the patient history database at the Riordan Clinic. Among people in our database who were treated with intravenous vitamin C (7.5 g to 50 g infusions) between 1997 and 2006, 178 patients showed elevated levels of EBV EA IgG (range 25 to 211 AU) and 40 showed elevated levels of EBV VCA IgM (range 25 to 140 AU). Most of these patients had a diagnosis of chronic fatigue syndrome, with the rest being diagnosed as having mononucleosis, fatigue, or EBV infection. Results Our data provide evidence that high dose intravenous vitamin C therapy has a positive effect on disease duration and reduction of viral antibody levels. Plasma levels of ascorbic acid and vitamin D were correlated with levels of antibodies to EBV. We found an inverse correlation between EBV VCA IgM and vitamin C in plasma in patients with mononucleosis and CFS meaning that patients with high levels of vitamin C tended to have lower levels of antigens in the acute state of disease. In addition, a relation was found between vitamin D levels and EBV EA IgG with lower levels of EBV early antigen IgG for higher levels of vitamin D. Conclusions The clinical study of ascorbic acid and EBV infection showed the reduction in EBV EA IgG and EBV VCA IgM antibody levels over time during IVC therapy that is consistent with observations from the literature that millimolar levels of ascorbate hinder viral infection and replication in vitro.

Polymorphic differences in SOD-2 may influence HCV viral clearance

Hepatitis C virus (HCV) is a pathogen causing chronic hepatitis, cirrhosis, and liver cancer occurring in about 3% of the world's population. Most individuals infected with HCV develop persistent viremia. Oxidative stress may play an important role in the pathogenesis of a number of diseases including HCV infection and diabetes mellitus. Polymorphisms in the antioxidant genes may determine cellular oxidative stress levels as a primary pathogenic role in HCV and/or in its complications. Patients with HCV and normal, healthy controls were investigated for a superoxide dismutase (SOD-2) polymorphism in the mitochondrial targeting sequence with Ala/Val (C-9T) substitution. Polymorphisms in antioxidant gene SOD-2 were carried out by PCR, restriction fragment length polymorphism assays and by polyacrylamide gel electrophoresis. For the SOD-2 polymorphism, the RNA positive group showed a higher percentage of "CT" genotype than the RNA negative group (89.3% vs. 66.1%, P = 0.001, χ(2)  = 11.9). The RNA negative group had more TT genotypes than the RNA positive group (27.4% vs. 6.80%, P = 0.01, χ(2)  = 11.6). The exposed uninfected group had an increased frequency of the "CT" genotype (86.2% vs. 66.1%, P = 0.02, χ(2)  = 5.5). The RNA positives had a higher frequency of the "CT" from the normal controls (72.1% vs. 89.2%, P = 0.005, χ(2)  = 7.8).

Hepatic Injury Correlates With Apoptosis, Regeneration, and Nitric Oxide Synthase Expression in Canine Chronic Liver Disease

Assessment of the clinical severity, pathogenesis, and prognosis of canine chronic liver disease poses significant challenges to clinicians and pathologists, relating in part to a lack of standardized terminology and assessment methods and also to a lack of understanding of the pathogenesis of chronic liver disease in the dog. This study graded the severity of necroinflammatory activity in chronic liver disease in dogs using a modification of Ishak’s grading scheme for human chronic liver disease and examined the association of grade score with hepatocellular apoptosis, regeneration, nitric oxide synthase isoform expression, copper and iron accumulation, and indicators of oxidative stress. Formalin-fixed, paraffin-embedded hematoxylin and eosin (HE)–stained liver biopsies from 45 dogs with chronic liver disease and 55 healthy control dogs were graded for various morphologic components of liver injury and response. The cumulative score for grade of necroinflammatory activity was strongly and significantly correlated with immunoreactive labels for hepatocellular proliferation (Ki-67); apoptosis (cleaved caspase-3); inducible nitric oxide synthase (iNOS) in lobular, portal, and septal stromal cells; endothelial nitric oxide synthase (eNOS) in hepatocytes and lobular, portal, and septal stromal cells; and total stainable hepatic iron. A weaker significant correlation was found between grade and accumulation of hepatocellular copper. No significant correlation was found between grade and immunoreactivity for malondialdehyde-protein adducts. These results document a method for grading of the severity of necroinflammatory disease in canine liver biopsies and show an association with increased iNOS and eNOS expression.

An assessment of pharmacokinetics and antioxidant activity of free silymarin flavonolignans in healthy volunteers: a dose escalation study

Milk thistle (Silybum marianum) extracts, one of the most widely used dietary supplements, contain a mixture of six major flavonolignans (silybin A, silybin B, isosilybin A, isosilybin B, silychristin, and silydianin) and other components. However, the pharmacokinetics of the free individual flavonolignans have been only partially investigated in humans. Furthermore, antioxidant effects of the extract, which may underlie the basis of many therapeutic effects, have not been thoroughly assessed. The present study evaluated the pharmacokinetics of the six major flavonolignans in healthy volunteers receiving single doses of either one (175 mg), two (350 mg), or three (525 mg) milk thistle capsule(s) on three separate study visits. Additionally, the steady-state pharmacokinetic parameters were determined after the subjects were administered one capsule three times daily for 28 consecutive days. Our results demonstrated that all six flavonolignans were rapidly absorbed and eliminated. In order of abundance, the exposure to free flavonolignans was greatest for silybin A followed by silybin B, isosilybin B, isosilybin A, silychristin, and silydianin. The systemic exposure to these compounds appeared linear and dose proportional. The disposition of flavonolignans was stereoselective, as evidenced by the apparent clearance of silybin B, which was significantly greater than silybin A, whereas the apparent clearance of isosilybin B was significantly lower than isosilybin A. The concentrations of urinary 8-epi-prostaglandin F2α, a commonly used biomarker of oxidative status in humans, were considerably decreased in study subjects after a 28-day exposure to the extract (1.3 ± 0.9 versus 0.8 ± 0.9 ng/mg creatinine) but failed to reach statistical significance (P = 0.076).

Oxidative stress and hepatitis C virus

The disproportionate imbalance between the systemic manifestation of reactive oxygen species and body’s ability to detoxify the reactive intermediates is referred to as oxidative stress. Several biological processes as well as infectious agents, physiological or environmental stress, and perturbed antioxidant response can promote oxidative stress. Oxidative stress usually happens when cells are exposed to more electrically charged reactive oxygen species (ROS) such as H2O2 or O2-. The cells’ ability to handle such pro-oxidant species is impeded by viral infections particularly within liver that plays an important role in metabolism and detoxification of harmful substances. During liver diseases (such as hepatocellular or cholestatic problems), the produced ROS are involved in transcriptional activation of a large number of cytokines and growth factors, and continued production of ROS and Reactive Nitrogen Species (RNS) feed into the vicious cycle. Many human viruses like HCV are evolved to manipulate this delicate pro- and antioxidant balance; thus generating the sustainable oxidative stress that not only causes hepatic damage but also stimulates the processes to reduce treatment of damage. In this review article, the oxidant and antioxidant pathways that are perturbed by HCV genes are discussed. In the first line of risk, the pathways of lipid metabolism present a clear danger in accumulation of viral induced ROS. Viral infection leads to decrease in cellular concentrations of glutathione (GSH) resulting in oxidation of important components of cells such as proteins, DNA and lipids as well as double strand breakage of DNA. These disorders have the tendency to lead the cells toward cirrhosis and hepatocellular carcinoma in adults due to constant insult. We have highlighted the importance of such pathways and revealed differences in the extent of oxidative stress caused by HCV infection.

Interactions Between Hepatitis C Virus and Mitochondria: Impact on Pathogenesis and Innate Immunity

Hepatitis C virus (HCV) causes a persistent chronic infection of hepatocytes resulting in progressive fibrosis and carcinogenesis. Abnormalities in mitochondria are prominent features of clinical disease where ultrastructural changes, alterations in electron transport, and excess reactive oxygen species (ROS) production occur. These mitochondrial abnormalities correlate with disease severity and resolve with viral eradication. Multiple viral proteins, particularly core and NS3/4a bind to mitochondria. The core and NS5a proteins primarily cause ER stress, ER Ca²⁺ release and enhance direct transfer of Ca²⁺ from ER to mitochondria. This results in electron transport changes, increased ROS production and sensitivity to mitochondrial permeability transition and cell death. The viral protease, NS3/4a, binds to mitochondria as well where it cleaves an important signaling adapter, MAVS, thus preventing viral clearance by endogenous interferon production. This review discusses the mechanisms by which HCV causes mitochondrial changes and consequences of these for disease.

Prolidase and oxidative stress in chronic hepatitis C

BACKGROUND

Hepatitis C infection represents a common healthcare issue worldwide. The present trial was designed to investigate the role of prolidase, an enzyme that is significantly involved in the biosynthesis of collagen, and of the oxidative stress that is considered to be involved in the pathogenesis of various diseases, in the chronic hepatitis C infection. The trial was performed to assess the serum prolidase enzyme level and the oxidative-antioxidative status and to determine the relation between the serum prolidase activity and the oxidative stress parameters.

METHODS

A total of 95 individuals, including 55 patients with chronic hepatitis C infection (CHC) and 40 healthy adults, were enrolled in the trial. The values for prolidase, the total antioxidant status (TAS), the total oxidative stress (TOS), the oxidative stress index (OSI), sulfhydryl (SH), lipid peroxidation LOOH, catalase (CAT), and ceruloplasmin were measured and compared between the patient groups.

RESULTS

The prolidase, TOS, LOOH, CAT, and the OSI values were higher in the chronic hepatitis C group compared to the control group (P < 0.001). The TAS, SH, and ceruloplasmin levels were lower in the CHC group relative to the control group (P < 0.001).

CONCLUSION

We suppose that the values of prolidase and the oxidative stress are increased while the antioxidant levels are decreased in CHC. As a result, prolidase and the oxidative stress seem to be related with the progression of the disease.

HCV and oxidative stress in the liver

Hepatitis C virus (HCV) is the etiological agent accounting for chronic liver disease in approximately 2-3% of the population worldwide. HCV infection often leads to liver fibrosis and cirrhosis, various metabolic alterations including steatosis, insulin and interferon resistance or iron overload, and development of hepatocellular carcinoma or non-Hodgkin lymphoma. Multiple molecular mechanisms that trigger the emergence and development of each of these pathogenic processes have been identified so far. One of these involves marked induction of a reactive oxygen species (ROS) in infected cells leading to oxidative stress. To date, markers of oxidative stress were observed both in chronic hepatitis C patients and in various in vitro systems, including replicons or stable cell lines expressing viral proteins. The search for ROS sources in HCV-infected cells revealed several mechanisms of ROS production and thus a number of cellular proteins have become targets for future studies. Furthermore, during last several years it has been shown that HCV modifies antioxidant defense mechanisms. The aim of this review is to summarize the present state of art in the field and to try to predict directions for future studies.

Branched-chain amino acid-enriched nutrients stimulate antioxidant DNA repair in a rat model of liver injury induced by carbon tetrachloride

Oxidative stress (OS) plays an important role in the progression of chronic liver disease including organ injury and hypoalbuminemia. Long-term oral supplementation with branched-chain amino acids (BCAAs) can inhibit liver dysfunction but their role in the prevention of liver fibrosis and injury to the liver is unclear. The aim of this study was to assess how BCAAs preserve liver function from OS. To investigate how BCAAs specifically prevent OS, we evaluated the effect of oral supplementation with BCAAs on OS using a rat liver cirrhosis model. Liver cirrhosis was induced in ten male Sprague-Dawley rats by administering carbon tetrachloride for 12 weeks. Five of the ten carbon tetrachloride-treated rats were assigned to a control group and five to a BCAA group. BCAA-supplementation significantly preserved plasma albumin concentrations and significantly inhibited the occurrence of organ injury as determined by blood chemistry analysis. Hepatic expression of OGG1 mRNA was increased in the BCAA group compared to the control group. In the BCAA group, increased hepatic levels of OGG1 protein were found by western blot. On the other hand, the number of 8-OHdG-positive cells was significantly higher in liver sections taken 1 month after carbon tetrachloride treatment. Furthermore, OGG1-positive cells were significantly increased in the hepatocytes around the central vein. BCAA was found to reduce OS, which could possibly lead to a decrease in the occurrence of hypoalbuminemia and organ injury. Our results indicate that BCAA-enriched nutrients stimulate antioxidant DNA repair in a rat model of liver injury induced by carbon tetrachloride.

Intravenous vitamin C in the treatment of shingles: results of a multicenter prospective cohort study

BACKGROUND

Vitamin C is an immune-relevant micronutrient, which is depleted in viral infections and this deficiency seems to play a critical role in the pathogenesis of herpes infections and in the development of postherpetic neuralgia. The objective of this observational multicenter study was to evaluate the utilization, safety and efficacy of intravenously administrated vitamin C in patients with shingles.

MATERIAL/METHODS

Between April 2009 and December 2010 16 general practitioners recorded data of 67 participants with symptomatic herpes zoster who received vitamin C intravenously (Pascorbin® 7.5 g/50 ml) for approximately 2 weeks in addition to standard treatment. The assessment of pain (VAS) and the dermatologic symptoms of shingles such as hemorrhagic lesions and the number of efflorescences were investigated in a follow-up observation phase of up to 12 weeks.

RESULTS

Mean declines of pain scores (VAS), number of affected dermatomes and efflorescences, and the presence of hemorrhagic vesicles between the baseline and follow-up assessments at 2 and 12 weeks were statistically significant. Overall, 6.4% of the participants experienced post-herpetic neuralgia. Common complaints such as general fatigue and impaired concentration also improved during the study. The effects and the tolerability of the treatment were evaluated positively by the physicians. The risk of developing PHN was reduced.

CONCLUSIONS

The data presented here provide evidence that concomitant use of intravenously administered ascorbic acid may have beneficial effects on herpes zoster-associated pain, dermatologic findings and accompanying common complaints. To confirm our findings, randomized, placebo-controlled clinical studies are necessary.

Hepatoprotective potential of astaxanthin against 2,3,7,8-tetrachlorodibenzo-p-dioxin in cultured rat hepatocytes

The purpose of this study was to evaluate the effect of carotenoid astaxanthin (ASTA) on cultured primary rat hepatocytes treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the cell viability (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, MTT), lactate dehydrogenase (LDH) activity, 8-oxo-2-deoxyguanosine (8-OH-dG), total antioxidant capacity (TAC), and total oxidative stress (TOS) levels, and liver micronucleus rates. ASTA (2.5, 5, and 10 µM) was added to cultures alone or simultaneously with TCDD (5 and 10 µM) for 48 h. The results of MTT and LDH assays showed that both doses of TCDD caused significant decrease in cell viability. Also, TCDD significantly increased TOS and decreased TAC level in rat hepatocytes. On the basis of increasing doses, the dioxin caused significant increase in micronucleated hepatocytes) and 8-OH-dG level as compared to control culture. The presence of ASTA with TCDD minimized its effects on primary hepatocytes cultures and DNA damages.

Can zinc enhance response interferon therapy for patients with HCV-related liver disease?

Patients with liver disease may be at risk of zinc depletion. Zinc supplementation has been shown to contribute to inhibition of liver fibrosis and improvement in hepatic encephalopathy. However, little is known about the anti-inflammatory effect of zinc on hepatitis C virus (HCV)-related chronic liver disease. The standard of care for chronic HCV has improved markedly since the approval of interferon (IFN) therapy more than a decade ago. Over the past 20 years, IFN therapy has improved to more effectively eliminate the virus, progressing from single IFN therapy to combination therapy with ribavirin (RBV) and finally to pegylated IFN (PEG-IFN) therapy. However, even combined therapy with PEG-IFN and RBV for 48 wk is unable to eliminate the virus in some 40% of hepatitis C cases, particularly those with genotype 1b and high viral load. Treatment options for patients who have relapsed or are refractory to treatment with PEG-IFN and RBV therefore need to be critically assessed. This paper overviews the relationship between chronic liver disease and zinc metabolism.

The effect of increased oxidative stress and ferritin in reducing the effectiveness of therapy in chronic hepatitis C patients

BACKGROUND/AIM

Chronic hepatitis C (CHC) patients have higher oxidative stress and ferritin than healthy individuals. However, the level of oxidative stress in CHC patients during treatment with peginterferon alpha-2a and ribavirin is not clear. The aims of our study are to investigate changes of thiobarbituric acid reactive substances (TBARS; indicated oxidative stress), total antioxidant status (TAS) and ferritin in CHC patients during therapy and to identify the correlation of these factors and the effectiveness of therapy.

METHODS

Sixty CHC patients were selected and were prescribed 180 μg of peginteferon alpha-2a once a week and a daily dose of 1000 to 1200 mg ribavirin for 6 months. Throughout the treatment course, blood samples were taken to determine TBARS, TAS, and liver inflammation profiles including ferritin, aspartate transaminase (AST) and alanine transaminase (ALT).

RESULTS

The level of TBARS increased before the 12th week of therapy. Additionally, the levels of TBARS were higher in non-rapid virological response (RVR) patients compared with RVR (p<0.01) in baseline and therapy at the 24th week. TAS was lower during therapy than at baseline. Levels of TAS were significantly higher in sustained virological response (SVR) patients than in non-SVR (p<0.01) in the 4th week post-therapy. We also found a positive correlation between the level of ferritin and liver inflammation during treatment (p<0.01). The levels of ferritin and ALT were lower in SVR than in non-SVR patients in the 4th week of post-therapy (p<0.01).

CONCLUSIONS

This study indicated that decreased ferritin, decreased TBARS and increased TAS status may improve the efficacy of treatment.

The effect of laurel leaf extract against toxicity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin in cultured rat hepatocytes

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a very toxic environmental pollutant that raises great public concern about its impact on human health. Recent studies indicate that laurel leaf extract exhibits antioxidant properties that can counter the toxic effects of certain compounds in the liver. The aim of this study was to assess how effective LE is against the toxicity of TCDD in a primary culture of rat hepatocytes. The extract (50 mg L(-1), 100 mg L(-1), and 200 mg L(-1)) was added to cultures alone or with TCDD (1.61 mg L(-1) and 3.22 mg L(-1)) for 48 hours. Cell viability was measured using the [3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide] (MTT) assay and the lactate dehydrogenase (LDH) cytotoxicity assay, while oxidative damage was assessed by measuring total antioxidant capacity (TAC) and total oxidative stress (TOS). DNA damage was also analysed using the micronucleus (MN) assay of the cultured hepatocytes. TCDD alone lowered, and laurel extract had no effect on cell viability. TCDD also increased TOS and significantly decreased TAC. It significantly increased the frequency of micronucleated hepatocytes in a dose-dependent manner. In cultures exposed to LE alone, TOS did not change and TAC significantly increased in a dose-dependent manner. Added to TCDD, laurel countered its toxic effects and showed protective effects against TCDD-mediated DNA damage. This points to the therapeutic potential of laurel against TCDD toxicity in the liver.

Oxidative stress, endogenous antioxidants, alcohol, and hepatitis C: pathogenic interactions and therapeutic considerations

Hepatitis C virus (HCV) is a blood-borne pathogen that was identified as an etiologic agent of non-A, non-B hepatitis in 1989. HCV is estimated to have infected at least 170 million people worldwide. The majority of patients infected with HCV do not clear the virus and become chronically infected, and chronic HCV infection increases the risk for hepatic steatosis, cirrhosis, and hepatocellular carcinoma. HCV induces oxidative/nitrosative stress from multiple sources, including inducible nitric oxide synthase, the mitochondrial electron transport chain, hepatocyte NAD(P)H oxidases, and inflammation, while decreasing glutathione. The cumulative oxidative burden is likely to promote both hepatic and extrahepatic conditions precipitated by HCV through a combination of local and more distal effects of reactive species, and clinical, animal, and in vitro studies strongly point to a role of oxidative/nitrosative stress in HCV-induced pathogenesis. Oxidative stress and hepatopathogenesis induced by HCV are exacerbated by even low doses of alcohol. Alcohol and reactive species may have other effects on hepatitis C patients such as modulation of the host immune system, viral replication, and positive selection of HCV sequence variants that contribute to antiviral resistance. This review summarizes the current understanding of redox interactions of HCV, outlining key experimental findings, directions for future research, and potential applications to therapy.

Relationship of oxidative stress in hepatitis B infection activity with HBV DNA and fibrosis

BACKGROUND

The aim of this study was to evaluate oxidative stress in various clinical forms of hepatitis B infection and to investigate its role in the development of the chronic form of the disease.

METHODS

Ninety-three patients with inactive hepatitis B surface antigen (HbsAg) carrier state (IHBCS), 65 patients with chronic hepatitis B infection (CHB), and 42 healthy adults were included in the study. The following values were measured and compared in patient groups: total antioxidant status (TAS), total oxidative stress (TOS), oxidative stress index (OSI), sulfhydryl (SH), lipid peroxidation (LOOH), catalase (CAT), and ceruloplasmin. In patients with chronic hepatitis B, these values were compared with HBV DNA and fibrosis levels.

RESULTS

ALT, TOS, LOOH, and OSI levels were higher in the CHB group compared to the other groups (P<0.001). Catalase levels increased in the CHB and IHBCS groups compared to the control group (P<0.001). Total aminooxidant and ceruloplasmin levels were found to be lowest in the CHB group and highest in the control group (P<0.001). Sulfhyrdyl was higher in the control group compared to the other groups (P<0.001). In the CHB group, there was no correlation between the HBV DNA and OSI (P>0.05).

CONCLUSIONS

These finding suggested that oxidative stress is associated with hepatitis B activity.

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.

Beneficial effect of astaxanthin on 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced liver injury in rats

Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) represents a potential health risk and hepatotoxicity. Astaxanthin (ASTA) exhibits antioxidant properties and can influence hepatotoxicity. Therefore, the present study was carried out for using ASTA against hepatotoxicity induced by TCDD in the liver of rats. Animals were treated intraperitoneally daily with TCDD (8 µg/kg body weight (b.w.)), ASTA (12.5 mg/kg b.w. and 25 mg/kg b.w.) and TCDD plus ASTA (12.5 and 25 mg/kg b.w.) for 21 days. TCDD significantly decreased the activities of antioxidant enzymes and resulted in serious pathological findings. Moreover, the rate of micronucleus (MN) in hepatocytes increased after treating with TCDD. The activities of enzymes, frequencies of MNs and liver histology in lower dosage group of ASTA remained unchanged compared with the control group. In rats treated with ASTA, at higher dosage alone, the MNs remained unchanged and the activities of antioxidant enzymes significantly increased. The presence of ASTA (except for lower dose) with TCDD alleviated its pathological effects in hepatic tissue. ASTA also prevented the suppression of antioxidant enzymes in the livers of animals exposed to TCDD and displayed a strong protective effect against MNs. Thus, the present findings might provide new insight into the development of therapeutic and preventive approaches of TCDD toxicity.