Peripheral type I interferon receptor correlated with oxidative stress in chronic hepatitis B virus infection

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.

The Role of Glutathione in Selected Viral Diseases

During inflammatory processes, immunocompetent cells are exposed to substantial amounts of free radicals and toxic compounds. Glutathione is a cysteine-containing tripeptide that is an important and ubiquitous antioxidant molecule produced in human organs. The intracellular content of GSH regulates the detoxifying capacity of cells, as well as the inflammatory and immune response. GSH is particularly important in the liver, where it serves as the major non-protein thiol involved in cellular antioxidant defense. There are numerous causes of hepatitis. The inflammation of the liver can be caused by a variety of infectious viruses. The relationship between oxidative stress and the hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis E virus (HEV) infection is not fully known. The aim of this study was to examine the relationship between hepatotropic viruses and glutathione status, including reduced glutathione (GSH) and oxidized glutathione (GSSG), as well as antioxidant enzymes, e.g., glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST) in liver diseases.

Maternal Immune Response to ZIKV Triggers High-Inflammatory Profile in Congenital Zika Syndrome

The immunological mechanisms involved in the development of congenital Zika syndrome (CZS) have yet to be fully clarified. This study aims to assess the immuno-inflammatory profile of mothers and their children who have been diagnosed with CZS. Blood samples, which were confirmed clinically using the plaque reduction neutralization test (PRNT), were collected from children with CZS and their mothers (CZS+ group). Samples were also collected from children who did not develop CZS and had a negative PRNT result and from their mothers (CZS- group). The data demonstrated a correlation between the leukocyte profile of CZS+ children and their mothers, more evident in monocytes. Monocytes from mothers of CZS+ children showed low expression of HLA and elevated hydrogen peroxide production. CZS+ children presented standard HLA expression and a higher hydrogen peroxide concentration than CZS- children. Monocyte superoxide dismutase activity remained functional. Moreover, when assessing the monocyte polarization, it was observed that there was no difference in nitrite concentrations; however, there was a decrease in arginase activity in CZS+ children. These data suggest that ZIKV infection induces a maternal immuno-inflammatory background related to the child's inflammatory response after birth, possibly affecting the development and progression of congenital Zika syndrome.

Suppression of Interferon-α Treatment Response by Host Negative Factors in Hepatitis B Virus Infection

Chronic hepatitis B virus (CHB) infection remains a major global public health issue for which there is still lacking effective curative treatment. Interferon-α (IFN-α) and its pegylated form have been approved as an anti-HBV drug with the advantage of antiviral activity and host immunity against HBV infection enhancement, however, IFN-α treatment failure in CHB patients is a challenging obstacle with 70% of CHB patients respond poorly to exogenous IFN-α treatment. The IFN-α treatment response is negatively regulated by both viral and host factors, and the role of viral factors has been extensively illustrated, while much less attention has been paid to host negative factors. Here, we summarized evidence of host negative regulators and parameters involved in IFN-α therapy failure, review the mechanisms responsible for these effects, and discuss the possible improvement of IFN-based therapy and the rationale of combining the inhibitors of negative regulators in achieving an HBV cure.

Mitochondrial dysfunction and mitophagy pathway activation in hepatitis E virus-infected livers of Mongolian gerbils

Recently, hepatitis E virus (HEV) has caused large outbreaks and presented a significant public health problem. Thus, the mechanism of HEV has attracted increasing research attention. Previous studies revealed that HEV infection induced hepatocyte injuries and structural and functional changes in mitochondria. These pathological changes affected the life cycle of hepatocytes. However, the precise underlying mechanism and the effector protein responsible for this process remain unclear. In the present study, mitochondrial function and the expression of mitophagy-associated mRNA transcripts and proteins were detected in an HEV- infected Mongolian gerbil model. Observation of ultrastructural changes in the liver of the inoculated group revealed the disappearance of mitochondrial cristae of mitochondrion, blurring of the bilayer structure and cavitation in the cytoplasm. The results showed that the mitochondrial transmembrane potential of decreased, mitochondrial transition pore (MPTP) opening increased, reactive oxygen species (ROS) production increased, and glutathione peroxidase (GSH-Px) activity decreased in the HEV-inoculated group. Moreover, the LC3, Beclin1, BNIP3L, Parkin, PINK1 and P62 mRNA levels were significantly increased (p < 0.05 and p < 0.01) in the inoculated group. Western blot and immunohistochemistry assay analyses detected the upregulation of the mitophagy-associated proteins LC3, Beclin1, BNIP3L, Parkin, PINK1 and P62 (p < 0.05 and p < 0.01) in HEV-infected gerbils. All these data demonstrated that HEV infection in vivo induced mitochondrial dysfunction and the activation of the mitophagy pathway, which might be one of the key factors in hepatocyte injury.

Changes in Glutathione Content in Liver Diseases: An Update

Glutathione (GSH), a tripeptide particularly concentrated in the liver, is the most important thiol reducing agent involved in the modulation of redox processes. It has also been demonstrated that GSH cannot be considered only as a mere free radical scavenger but that it takes part in the network governing the choice between survival, necrosis and apoptosis as well as in altering the function of signal transduction and transcription factor molecules. The purpose of the present review is to provide an overview on the molecular biology of the GSH system; therefore, GSH synthesis, metabolism and regulation will be reviewed. The multiple GSH functions will be described, as well as the importance of GSH compartmentalization into distinct subcellular pools and inter-organ transfer. Furthermore, we will highlight the close relationship existing between GSH content and the pathogenesis of liver disease, such as non-alcoholic fatty liver disease (NAFLD), alcoholic liver disease (ALD), chronic cholestatic injury, ischemia/reperfusion damage, hepatitis C virus (HCV), hepatitis B virus (HBV) and hepatocellular carcinoma. Finally, the potential therapeutic benefits of GSH and GSH-related medications, will be described for each liver disorder taken into account.

Decreased Methylation of IFNAR Gene Promoter from Peripheral Blood Mononuclear Cells Is Associated with Oxidative Stress in Chronic Hepatitis B

Type I interferons (IFNs) play an antiviral effect by binding to type I interferon receptor (IFNAR). Oxidative stress might induce the gene promoter methylation. The purpose of our study was to evaluate the potential relationship between the methylation of IFNAR promoter and the status of oxidative stress in chronic hepatitis B (CHB). The methylation level of the IFNAR promoter in patients with CHB and healthy controls (HCs) was determined by methylation-specific polymerase chain reaction (MS-PCR). The quantitative real-time PCR (RT-qPCR) was used to evaluate the IFNAR mRNA status in peripheral blood mononuclear cells from CHB and HCs. Level of plasma-soluble IFNAR and oxidative stress parameters, including malondialdehyde (MDA) and glutathione (GSH) were determined by enzyme-linked immunosorbent assay (ELISA). The frequency of IFNAR promoter methylation in CHB patients was significantly lower than that of HCs. The IFNAR mRNA level of patients with CHB was higher than HCs. MDA level was higher in CHB patients, whereas GSH level was lower in CHB patients than that of HCs. In CHB patients, plasma MDA level was significantly higher with IFNAR promoter methylation than unmethylation, and soluble IFNAR in the circulation of methylated patients with CHB was decreased than unmethylated patients with CHB. Our results indicated that the IFNAR promoter methylation might have a potential relationship with the status of oxidative stress.

HTLV-1 infection-induced motor dysfunction, memory impairment, depression, and brain tissues oxidative damage in female BALB/c mice

AIMS

The HTLV-1 infection is associated with a neuro-inflammatory disease. In the present study, the behavioral consequences and brain oxidative damages were evaluated in HTLV-1-infected BALB/c mice.

MATERIAL AND METHODS

20 female BALB/c mice were divided into two groups comprising control and HTLV-1-infected. The HTLV-1-infected group was inoculated with a 10⁶ MT-2 HTLV-1-infected cell line. Two months later, the behavioral tests were conducted. Finally, oxidative stress was assessed in the cortex and hippocampus tissues.

KEY FINDINGS

In the HTLV-1-infected group, running time and latency to fall, travel distance and time spent in the peripheral zone, total crossing number and total traveled distance in open field test, the latency of entrance into the dark compartment in the passive avoidance test, the new object exploration percentage, and discrimination ratio were significantly lower than in the control group. The immobility time, time spent in the dark compartment in passive avoidance test, and total exploration time significantly increased in the HTLV-1-infected group compared to the control group. In the cortical tissue of the HTLV-1 group, the malondialdehyde levels were elevated while the total thiol levels decreased in comparison to the control group. The activity of superoxide dismutase in the cortical and hippocampal tissues, and catalase activity in cortical tissue significantly decreased in the HTLV-1 group in comparison to the control group.

SIGNIFICANCE

The HTLV-1 infection seems to induce depression-like behavior, motor dysfunction, disruption in working and fear memory and also oxidative stress in the cortex and hippocampus.

Immune regulation of the unfolded protein response at the mucosal barrier in viral infection

Protein folding in the endoplasmic reticulum (ER) is subject to stringent quality control. When protein secretion demand exceeds the protein folding capacity of the ER, the unfolded protein response (UPR) is triggered as a consequence of ER stress. Due to the secretory function of epithelial cells, UPR plays an important role in maintaining epithelial barrier function at mucosal sites. ER stress and activation of the UPR are natural mechanisms by which mucosal epithelial cells combat viral infections. In this review, we discuss the important role of UPR in regulating mucosal epithelium homeostasis. In addition, we review current insights into how the UPR is involved in viral infection at mucosal barriers and potential therapeutic strategies that restore epithelial cell integrity following acute viral infections via cytokine and cellular stress manipulation.

Oxidative stress, a trigger of hepatitis C and B virus-induced liver carcinogenesis. Oncotarget. 2017;8:3895-3932. [PMID: 27965466 PMCID: PMC5354803 DOI: 10.18632/oncotarget.13904]

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.

The Ca2+/CaMKK2 axis mediates the telbivudine induced upregulation of creatine kinase: Implications for mechanism of antiviral nucleoside analogs' side effect

Telbivudine (LdT), a widely prescribed anti-hepatitis B virus (HBV) drug for the treatment of chronic Hepatitis B (CHB), causes adverse reactions ranging from creatine kinase (CK) elevation to myopathy. The purpose of this study was to explore the mechanism(s) of LdT induced CK elevation. The effects of LdT on mitochondrial morphology and proteins (TK2 and β-actin), oxidative stress, intracellular Ca²⁺ levels, Ca²⁺-related signaling pathway (CaMKK2/AMPK), and Ca²⁺-related biomarkers such as superoxide dismutase (SOD) and malondialdehyde (MDA) were assessed in human skeletal muscle cells (HSKMCs). The results showed that LdT induced a dose-dependent increase in CK activity in HSKMCs, without affecting mitochondrial morphology, and TK2 and β-actin protein levels, following 72 h of treatment. In addition, LdT increased Ca²⁺ production, ROS generation, MDA and lipid peroxide (LPO) levels, and activated the CaMKK2/AMPK signaling pathway. Moreover, these effects were attenuated by the BAPIA-AM (the calcium chelator). We also confirmed the presence of relevant markers (MDA, LPO, and SOD) in serum from CHB patients after LdT treatment, and found that CK was positively correlated with MDA and LPO, and negatively associated with SOD. These findings indicate that LdT induces CK elevation and oxidative stress associated with imbalance of intracellular Ca²⁺ in HSKMCs, suggesting that Ca²⁺/CaMKK2 axis imbalance may underlie human LdT-induced CK elevation. The present findings provide a solid basis for assessing the mechanism of drug-induced CK elevation, which can help develop new tools for the prevention and treatment of diseases associated with drug-induced CK elevation.

Hepatitis B and its Relationship With Oxidative Stress

CONTEXT

Despite the great breakthroughs we have witnessed in the last 50 years in the prevention, diagnosis, and treatment of hepatitis B, we are still far from eradicating or even curing the disease. Achieving further progress in controlling this disease will not be possible without discovering the exact pathogenesis behind it. One prime suspect in the pathogenesis of various diseases is oxidative stress. This review will exclusively explore hepatitis B in the context of oxidative stress to obtain a more comprehensive clinical perspective on its pathogenesis and eventual medical therapy.

EVIDENCE ACQUISITION

We systematically searched PubMed, Google Scholar, Web of Science, EMBASE, and Scopus using an extensive list of keywords in the following three categories: 1) Hepatitis B and oxidation 2) Hepatitis B and antioxidant system 3) Effects of approved anti-hepatitis B drugs on redox status. All relevant articles were obtained and reviewed carefully after the exclusion criteria were deployed.

RESULTS

There is great evidence indicating extensive oxidative stress occurs in hepatitis B. This oxidative stress takes place on multiple levels, including lipid peroxidation, DNA oxidation, protein oxidation, and reactive oxygen and nitrogen species production. However, there are also conflicting results with regard to antioxidant therapy and antioxidant status in hepatitis B, some of which may be explained by the concept of "compensatory gaps." Nevertheless, further studies are indicated to reach a more thorough judgment.

CONCLUSIONS

Despite the presence of vast oxidative stress in hepatitis B, antioxidant therapy is not always effective as a treatment strategy, especially considering that antioxidants can act as "double-edged swords" or antioxidants; if not used at the right time or place or in the right combination, these substances can easily become pro-oxidants. Therefore, several studies will be needed to determine suitable antioxidant therapies. We propose the "2-step Combined Antioxidant Adjuvant Therapy for hepatitis B (2CAAT Hep B)" as a new strategy for antioxidant adjuvant therapy. We also suggest developing an international platform and database for antioxidant adjuvant therapy in hepatitis B (IPAATH and IDAATH) to canalize this field of research in a standardized direction, especially when complexity is a problem.