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

Effects of Zinc Supplementation on Inflammatory Status and Nonalcoholic Steatohepatitis in Overweight or Obese Children: a Randomized Clinical Trial

The purpose of the present clinical trial was to determine the impact of zinc supplementation on serum liver enzymes, steatosis severity, lipid profile, and inflammatory status in overweight or obese children with nonalcoholic steatohepatitis (NASH). This randomized controlled trial was conducted by enrolling 60 children with NASH, aged 10-18 years old. The participants were randomly assigned to two groups that received either 30 mg/day of elemental zinc or placebo for 16 weeks. The severity of liver steatosis was evaluated using liver ultrasonography. Fasting blood samples were collected from each patient at the beginning and after 16 weeks of intervention to measure biochemical parameters. Following a 16-week intervention, zinc supplementation compared with placebo significantly decreased serum alanine aminotransferase (ALT) concentrations and high-sensitivity C-reactive protein and considerably enhanced HDL-cholesterol values. However, zinc intake had no considerable impact on aspartate aminotransferase, the severity of liver steatosis, anthropometric parameters, and other lipid indices versus the placebo group. Overall, zinc supplementation showed a promising impact on serum ALT, HDL-cholesterol, and inflammatory status in overweight or obese children suffering from NASH. Zinc supplementation may be a new strategy for the amelioration of NASH in overweight or obese children. This trial has been registered on the Iranian website for registration of clinical trials with the special ID of IRCT20200531047614N1 ( https://www.irct.ir/trial/48543 ).

The effects of zinc supplementation on the metabolic factors in patients with non-alcoholic fatty liver disease: a randomized, double-blinded, placebo-controlled clinical trial

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is associated with metabolic factors including obesity, dyslipidemia, insulin resistance, oxidative stress, and elevated inflammatory factors. Zinc (Zn) supplementation has been investigated as a potential adjunctive therapy in managing NAFLD outcomes.

METHODS

In this randomized, double-blinded, controlled clinical trial, 50 overweight or obese participants with NAFLD were randomized into 2 groups of 25 and received either 30 mg of daily Zn or a placebo for 8 weeks. Both groups were invited to follow a balanced energy-restricted diet and physical activity recommendations.

RESULTS

Based on the between-group comparison, Zn supplementation caused a significant increase in the Zn level (P < 0.001) and a significant decrease in weight (P = 0.004), body mass index (BMI) (P = 0.002), waist circumference (P = 0.010), aspartate transaminase (AST) (P = 0.033), total cholesterol (TC) (P = 0.045), and low-density lipoprotein cholesterol (LDL-C) (P = 0.014), but it had no significant effect on alanine transaminase (ALT), fasting blood sugar (FBS), insulin, homeostasis model assessment of insulin resistance (HOMA-IR), high-density lipoprotein (HDL), triglyceride (TG), high-sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), and total antioxidant capacity (TAC) (P > 0.05).

CONCLUSION

The results of the present study indicated that 8-week supplementation of 30 mg daily Zn may increase the Zn serum level and decline anthropometric parameters, AST, TC, and LDL-C in NAFLD patients, so further research is suggested in the future.

TRIAL REGISTRATION

The trial was retrospectively registered at IRCT.ir as IRCT20191015045113N1 (December/8/2019).

Interplay between zinc and cell proliferation and implications for the growth of livestock

Zinc (Zn) plays a critical role in the growth of livestock, which depends on cell proliferation. In addition to modifying the growth associated with its effects on food intake, mitogenic hormones, signal transduction and gene transcription, Zn also regulates body weight gain through mediating cell proliferation. Zn deficiency in animals leads to growth inhibition, along with an arrest of cell cycle progression at G0/G1 and S phase due to depression in the expression of cyclin D/E and DNA synthesis. Therefore, in the present study, the interplay between Zn and cell proliferation and implications for the growth of livestock were reviewed, in which Zn regulates cell proliferation in several ways, especially cell cycle progression at the G0/G1 phase DNA synthesis and mitosis. During the cell cycle, the Zn transporters and major Zn binding proteins such as metallothioneins are altered with the requirements of cellular Zn level and nuclear translocation of Zn. In addition, calcium signaling, MAPK pathway and PI3K/Akt cascades are also involved in the process of Zn-interfering cell proliferation. The evidence collected over the last decade highlights the necessity of Zn for normal cell proliferation, which suggests Zn supplementation should be considered for the growth and health of poultry.

Antiviral activity of zinc against hepatitis viruses: current status and future prospects

Viral hepatitis is a major public health concern globally. World health organization aims at eliminating viral hepatitis as a public health threat by 2030. Among the hepatitis causing viruses, hepatitis B and C are primarily transmitted via contaminated blood. Hepatitis A and E, which gets transmitted primarily via the feco-oral route, are the leading cause of acute viral hepatitis. Although vaccines are available against some of these viruses, new cases continue to be reported. There is an urgent need to devise a potent yet economical antiviral strategy against the hepatitis-causing viruses (denoted as hepatitis viruses) for achieving global elimination of viral hepatitis. Although zinc was known to mankind for a long time (since before Christ era), it was identified as an element in 1746 and its importance for human health was discovered in 1963 by the pioneering work of Dr. Ananda S. Prasad. A series of follow up studies involving zinc supplementation as a therapy demonstrated zinc as an essential element for humans, leading to establishment of a recommended dietary allowance (RDA) of 15 milligram zinc [United States RDA for zinc]. Being an essential component of many cellular enzymes and transcription factors, zinc is vital for growth and homeostasis of most living organisms, including human. Importantly, several studies indicate potent antiviral activity of zinc. Multiple studies have demonstrated antiviral activity of zinc against viruses that cause hepatitis. This article provides a comprehensive overview of the findings on antiviral activity of zinc against hepatitis viruses, discusses the mechanisms underlying the antiviral properties of zinc and summarizes the prospects of harnessing the therapeutic benefit of zinc supplementation therapy in reducing the disease burden due to viral hepatitis.

Zinc in Human Health and Infectious Diseases

During the last few decades, the micronutrient zinc has proven to be an important metal ion for a well-functioning immune system, and thus also for a suitable immune defense. Nowadays, it is known that the main cause of zinc deficiency is malnutrition. In particular, vulnerable populations, such as the elderly in Western countries and children in developing countries, are often affected. However, sufficient zinc intake and homeostasis is essential for a healthy life, as it is known that zinc deficiency is associated with a multitude of immune disorders such as metabolic and chronic diseases, as well as infectious diseases such as respiratory infections, malaria, HIV, or tuberculosis. Moreover, the modulation of the proinflammatory immune response and oxidative stress is well described. The anti-inflammatory and antioxidant properties of zinc have been known for a long time, but are not comprehensively researched and understood yet. Therefore, this review highlights the current molecular mechanisms underlying the development of a pro-/ and anti-inflammatory immune response as a result of zinc deficiency and zinc supplementation. Additionally, we emphasize the potential of zinc as a preventive and therapeutic agent, alone or in combination with other strategies, that could ameliorate infectious diseases.

Investigation of the clinical efficacy of Zn supplementation in improvement of oxidative stress parameters: A systematic review and dose-response meta-analysis of controlled clinical trials

BACKGROUND/OBJECTIVES

Clinical efficacy of zinc (Zn) supplementation in the improvement of oxidative stress biomarkers has been investigated in some clinical trial studies. The purpose of the current dose-response meta-analysis is to systematically aggregate and evaluate all related studies to highlight the possible effect of Zn supplementation on oxidative stress.

METHODS

Systematic search was performed on Scopus, PubMed/Medline, Web of Science and Embase up to 31 December 2020. The random effect method was used to perform pooled analysis. Possible sources of heterogeneity were found using subgroup analysis and meta-regression. In the presence of publication bias, trim and fill analysis was performed to adjust the results. Non-linear relationship between effect size and variables was investigated by performing dose-response analysis. The quality of included studies was assessed using Cochrane Collaboration's tool.

RESULTS

Pooled-analysis of 18 studies showed that Zn supplementation improved MDA and Hcys levels (SMD = -1.53 μmol/L; 95% CI: -2.22, -0.85; P < .001 and SMD = -0.62 μmol/L; 95% CI: -1.08, -0.15; P < .001, respectively). There was no significant effect of Zn supplementation on TBARS (SMD = -0.59 μmol/l; 95% CI: -1.31, 0.13; P = .108). Zn had maximum reducing effect on MDA in <40 mg/day dosage.

CONCLUSION

Zn supplementation reduces MDA and Hcys levels, but not TBARS level. Supplementation with Zn <40 mg/day has an optimum effect on MDA level. Zn supplementation could be considered clinically as a beneficial approach in amending oxidative stress.

Metallothionein 1: A New Spotlight on Inflammatory Diseases

MT1 has been demonstrated to be an essential stress protein in maintaining physiological balance and regulating immune homeostasis. While the immunological involvement of MT1 in central nervous system disorders and cancer has been extensively investigated, mounting evidence suggests that MT1 has a broader role in inflammatory diseases and can shape innate and adaptive immunity. In this review, we will first summarize the biological features of MT1 and the regulators that influence MT1 expression, emphasizing metal, inflammation, and immunosuppressive factors. We will then focus on the immunoregulatory function of MT1 on diverse immune cells and the signaling pathways regulated by MT1. Finally, we will discuss recent advances in our knowledge of the biological role of MT1 in several inflammatory diseases to develop novel therapeutic strategies.

Medicinal Plants and Zinc: Impact on COVID-19 Pandemic

The world is currently grappling with the coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The infection can cause fever, a dry cough, fatigue, severe pneumonia, respiratory distress syndrome, and in some cases death. There is currently no effective antiviral SARS-CoV-2 drug. To reduce the number of infections and deaths, it is critical to focus on strengthening immunity. This review aims to conduct a comprehensive search on the previous studies using Google Scholar, ScienceDirect, Medline, PubMed, and Scopus for the collection of research papers based on the role of zinc in the immune system, the antiviral activity of zinc, the effect of zinc supplementation in respiratory infections, the therapeutic approaches against viral infections based on medicinal plants, and the role of plants' bioactive molecules in fighting viral infections. In conclusion, we highlighted the pivotal role of zinc in antiviral immunity and we suggested the bioactive molecules derived from medicinal plants as a search matrix for the development of anti-SARS-CoV-2 drugs.

Zinc Administration and Improved Serum Markers of Hepatic Fibrosis in Patients with Autoimmune Hepatitis

AIM

The aim of the present study is to investigate the effect of long-term zinc supplementation, which is important for the activation of various enzymes that contribute to antioxidant and antifibrotic activities, on the improvement of serum fibrotic markers in patients with autoimmune hepatitis (AIH).

METHODS

A total of 38 patients with AIH under regular treatment at our hospital who provided their consent for being treated with polaprezinc (75 mg twice daily) were included and classified into 2 groups: the patients with zinc elevation (n = 27) and the patients without zinc elevation (n = 11). Serum biomarker of fibrosis, protein expression levels of matrix metalloproteinases (MMPs), and their inhibitors (TIMPs) were evaluated.

RESULTS

A significant difference was found between the variability of serum procollagen type Ⅲ and collagen type Ⅳ-7S between the 2 groups before and after zinc administration for more than 24 months (p = 0.043 and p = 0.049). In the patients with zinc elevation, no significant changes were found in collagenase (MMP-1 and MMP-13) before and after zinc administration, whereas a significant increase in the expression of gelatinase (MMP-2 and MMP-9) was found after administration (p = 0.021 and p = 0.005). As for the relative ratio of MMPs to TIMPs, only MMP-9 to TIMP-1 showed a significant increase (p = 0.004).

CONCLUSIONS

Long-term treatment with polaprezinc has been demonstrated to safely improve serum fibrosis indices through increases in MMP-2/-9 and MMP-9/TIMP-1 and is expected to be well combined with direct antifibrotic therapies such as molecularly targeted agents.

COVID-19 pandemic: Can zinc supplementation provide an additional shield against the infection?

Coronavirus disease-19 (COVID-19)-induced severe acute respiratory syndrome is a global pandemic. As a preventive measure, human movement is restricted in most of the world. The Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), along with the World Health Organization (WHO) have laid out some therapeutic guidelines for the infected patients. However, other than handwashing and vigilance surrounding commonly encountered oronasal symptoms and fever, no universally available prophylactic measure has yet been established. In a pandemic, the accessibility of a prophylactic biologically active substance is crucial. Ideally, it would be something readily available at a low price to a larger percentage of the population with minimal risk. Studies have demonstrated that zinc may reduce viral replication and increase immune responses. While consuming zinc (within the recommended upper safety limits), as a prophylactic might provide an additional shield against the initiation and progression of COVID-19 would need clinical studies, the potential clearly exists. Even after vaccination, low zinc status may affect the vaccination responses.

The Effects of Zinc Supplementation on C-Reactive Protein and Inflammatory Cytokines: A Meta-Analysis and Systematical Review

Zinc is known for anti-inflammatory and antioxidant roles. In this meta-analysis, we aim to evaluate the impact of zinc supplementation on inflammatory markers, acute-phase reactants, and serum zinc level during inflammatory and infectious diseases. PubMed, Scopus, and Web of Science databases were screened systematically with the terms "zinc supplementation" AND "CRP" OR "IL-1β" OR "IL-2" OR "IL-6" OR "IL-10" OR "IL-12" OR "TNF-α" OR "TGF-β" OR "IFN-γ" OR "WBC (clinical trial)" OR "macrophage (clinical trial)" OR "lymphocyte (clinical trial)" OR "neutrophil (clinical trial)" OR "virus (clinical trial)" OR "antiviral (clinical trial)" for all databases. A total of 2,258 publications were screened, and 73 articles had suitable data for the meta-analysis. Serum zinc level was significantly higher in supplementation group compared with controls [P = 0.0006, mean difference: 11.35 (4.84, 17.87)] (n = 37). Zinc supplementation downregulates acute-phase reactants, especially serum C-reactive protein (CRP) in adults [P < 0.00001, mean difference: -0.75 (-0.98, -0.52)] (n = 22) and pregnant women [FEM P < 0.00001, mean difference: -1.77 (-2.53, -1.00)] (n = 3) but not in children [REM P = 0.10, mean difference: -0.85 (-1.86, 0.17)] (n = 3). In subgroups analysis of chronic inflammatory diseases, serum CRP [REM P < 0.00001, mean difference: -0.57 (-0.76, -0.38)] were significantly lower in zinc-supplemented patients compared with no intervention group. Zinc supplementation (mg/day) correlated with serum interferon-gamma (IFN-γ) level (P = 0.018, r = 1,000). In the nonsupplemented group, serum zinc correlated with serum interleukin-6 (IL-6) level (P = 0.041, r = -0.829) and serum tumor necrosis factor alpha (TNF-α) level (P = 0.063, r = 0.730). Zinc intake correlated with serum zinc (P = 0.0428, r = 0.5115) and TNF-α (P = 0.0043, r = -0.9461). This meta-analysis shows that zinc supplementation improves CRP levels in adults and pregnant women. It might have modulatory effects on cytokine secretions and blood cells in inflammatory and infectious diseases. For the first time, we investigated the effects of zinc supplementation on inflammatory cytokine.

The Implications of Zinc Therapy in Combating the COVID-19 Global Pandemic

The global pandemic from COVID-19 infection has generated significant public health concerns, both health-wise and economically. There is no specific pharmacological antiviral therapeutic option to date available for COVID-19 management. Also, there is an urgent need to discover effective medicines, prevention, and control methods because of the harsh death toll from this novel coronavirus infection. Acute respiratory tract infections, significantly lower respiratory tract infections, and pneumonia are the primary cause of millions of deaths worldwide. The role of micronutrients, including trace elements, boosted the human immune system and was well established. Several vitamins such as vitamin A, B6, B12, C, D, E, and folate; microelement including zinc, iron, selenium, magnesium, and copper; omega-3 fatty acids as eicosapentaenoic acid and docosahexaenoic acid plays essential physiological roles in promoting the immune system. Furthermore, zinc is an indispensable microelement essential for a thorough enzymatic physiological process. It also helps regulate gene-transcription such as DNA replication, RNA transcription, cell division, and cell activation in the human biological system. Subsequently, zinc, together with natural scavenger cells and neutrophils, are also involved in developing cells responsible for regulating nonspecific immunity. The modern food habit often promotes zinc deficiency; as such, quite a few COVID-19 patients presented to hospitals were frequently diagnosed as zinc deficient. Earlier studies documented that zinc deficiency predisposes patients to a viral infection such as herpes simplex, common cold, hepatitis C, severe acute respiratory syndrome coronavirus (SARS-CoV-1), the human immunodeficiency virus (HIV) because of reducing antiviral immunity. This manuscript aimed to discuss the various roles played by zinc in the management of COVID-19 infection.

Role of zinc supplementation in the management of chronic liver diseases: A systematic review and meta-analysis

INTRODUCTION AND OBJECTIVES

Zinc deficiency has been associated with poor prognosis in chronic liver disease. This systematic review and meta-analysis aimed to evaluate the role of zinc supplementation in the management of chronic liver diseases.

MATERIALS AND METHODS

We searched MEDLINE, LILACS, EMBASE, and Cochrane CENTRAL databases from inception to August 2018. We included randomized controlled trials evaluating adult patients with chronic liver disease of any etiology receiving zinc supplementation. Studies with other designs or evaluating chronic conditions other than liver disease were excluded. Two reviewers independently screened and extracted data from eligible studies. Study quality was assessed using the Cochrane Collaboration's tool for assessing risk of bias in randomized studies.

RESULTS

Of 1315 studies screened, 13 were included. Six assessed chronic hepatitis C treatment, with a relative risk of 0.83 indicating no protective effect of zinc supplementation on the improvement of sustained virological response. Three evaluated response to hepatic encephalopathy treatment, with a relative risk of 0.66 indicating a favorable effect of zinc supplementation on clinical improvement of this condition. Of four studies evaluating the management of cirrhosis, two analyzed the effect of zinc supplementation on serum albumin levels, with no statistical difference between zinc and placebo groups.

CONCLUSIONS

Clinical trials assessing zinc supplementation in liver diseases do not show benefits in terms of clinical improvement or disease halting. There are possible benefits of zinc supplementation on hepatic encephalopathy, however, this is based on limited evidence. This research question is still open for evaluation in larger, well-designed, clinical trials.

The Effect of Zinc Supplementation on Steatosis Severity and Liver Function Enzymes in Overweight/Obese Patients with Mild to Moderate Non-alcoholic Fatty Liver Following Calorie-Restricted Diet: a Double-Blind, Randomized Placebo-Controlled Trial

The role of zinc is known in balancing the oxidant/antioxidant system and also in improving insulin resistance in many diseases. Recently, in vivo and in vitro studies revealed roles of zinc on lipophagy and suppressing hepatic lipid deposition. The present study is the first double-blind randomized clinical trial that investigated the effect of zinc supplement on clinical manifestations and anthropometric parameters of overweight/obese non-alcoholic fatty liver patients following calorie-restricted diet. Fifty-six overweight/obese subjects with confirmed non-alcoholic fatty liver disease (NAFLD) using ultrasonography were randomized to treatment (calorie-restricted diet plus 30 mg/day zinc supplement) or placebo (calorie-restricted diet and placebo) groups. Serum liver enzymes and liver steatosis were measured at the baseline and 12 weeks post-intervention. Anthropometric measurements and food recalls were collected at the beginning, weeks 6 and 12. Zinc supplementation significantly elevated serum zinc concentrations in the treatment group (p < 0.001). Treatment also reduced alanine aminotransferase and γ-glutamyl transpeptidase enzymes in the treatment group (p < 0.05). Waist circumference was also significantly lowered in the zinc group (p < 0.05). Liver steatosis and fatty liver index changes were not significant between the groups. Overall, beneficial effects of zinc supplementation were shown on serum levels of zinc and liver enzymes in overweight/obese NAFLD patients.

COVID-19 Pandemic: Can Maintaining Optimal Zinc Balance Enhance Host Resistance?

The novel coronavirus disease 2019 (COVID-19) is now officially declared as a pandemic by the World Health Organization (WHO), and most parts of the world are taking drastic measures to restrict human movements to contain the infection. Millions around the world are wondering, if there is anything that could be done, other than maintaining high personal hygiene, and be vigilant of the symptoms, to reduce the spread of the disease and chances of getting infected, or at least to lessen the burden of the disease, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The National and International health agencies, including the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the WHO have provided clear guidelines for both preventive and treatment suggestions. In this article, I will briefly discuss, why keeping adequate zinc balance might enhance the host response and be protective of viral infections.

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

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

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.

Histidine-containing dipeptides reduce central obesity and improve glycaemic outcomes: A systematic review and meta-analysis of randomized controlled trials

Supplementation with histidine-containing dipeptides has been shown to improve obesity and glycaemic outcomes in animal and human studies. We conducted a systematic review and meta-analysis of randomized controlled trials to examine these effects. Electronic databases were searched investigating the effects of histidine-containing dipeptides supplementation on anthropometric and glycaemic outcomes. Meta-analyses were performed using random-effects models to calculate the weighted mean difference and 95% confidence interval. There were 30 studies for the systematic review and 23 studies pooled for meta-analysis. Histidine-containing dipeptide groups had a lower waist circumference (WMD [95% CI] = -3.53 cm [-5.65, -1.41], p = 0.001) and HbA1c level (WMD [95% CI] = -0.76% (8.5 mmol/mol) [-1.29% (14.3 mmol/mol), -0.24% (2.8 mmol/mol)], p = 0.004) at follow-up compared with controls. In sensitivity analyses of studies with low risk of bias, waist circumference, HbA1c, and fasting glucose levels (WMD [95% CI] = -0.63 mmol/L [-1.09, -0.18], p = 0.006) were significantly lower in intervention groups versus controls. There was also a trend toward lower fat mass (p = 0.09), insulin resistance (p = 0.07), and higher insulin secretion (p = 0.06) in intervention versus control groups. Supplementation with histidine-containing dipeptides may reduce central obesity and improve glycaemic outcomes. Further studies exploring histidine-containing dipeptide use in obesity and diabetes prevention and treatment are warranted.

A Review of Zinc-L-Carnosine and Its Positive Effects on Oral Mucositis, Taste Disorders, and Gastrointestinal Disorders

Zinc-L-carnosine (ZnC), also called polaprezinc known as PepZin GI™, is a chelated compound that contains L-carnosine and zinc. It is a relatively new molecule and has been associated with multiple health benefits. There are several studies that support ZnC’s benefits in restoring the gastric lining, healing other parts of the gastrointestinal (GI) tract, improving taste disorders, improving GI disorders, and enhancing skin and liver. Oral mucositis is a common complication of cytotoxic radiotherapy and/or chemotherapy. It occurs in almost every person with head and neck cancer who receive radiotherapy. It is often overlooked because it is not considered life threatening. However, mucositis often leads to a decreased quality of life and cessation of treatment, ultimately decreasing positive outcomes. Therefore, solutions to address it should be considered. The primary mechanisms of action are thought to be localized and related to ZnC’s anti-inflammatory and antioxidant functions. Therefore, the purpose of this review is to discuss the research related to ZnC and to explore its benefits, especially in the management of conditions related to damaged epithelial cells, such as oral mucositis. Evidence supports the safety and efficacy of ZnC for the maintenance, prevention, and treatment of the mucosal lining and other epithelial tissues. The research supports its use for gastric ulcers (approved in Japan) and conditions of the upper GI and suggests other applications, particularly for oral mucositis.

The Role of Zinc in Antiviral Immunity

Zinc is an essential trace element that is crucial for growth, development, and the maintenance of immune function. Its influence reaches all organs and cell types, representing an integral component of approximately 10% of the human proteome, and encompassing hundreds of key enzymes and transcription factors. Zinc deficiency is strikingly common, affecting up to a quarter of the population in developing countries, but also affecting distinct populations in the developed world as a result of lifestyle, age, and disease-mediated factors. Consequently, zinc status is a critical factor that can influence antiviral immunity, particularly as zinc-deficient populations are often most at risk of acquiring viral infections such as HIV or hepatitis C virus. This review summarizes current basic science and clinical evidence examining zinc as a direct antiviral, as well as a stimulant of antiviral immunity. An abundance of evidence has accumulated over the past 50 y to demonstrate the antiviral activity of zinc against a variety of viruses, and via numerous mechanisms. The therapeutic use of zinc for viral infections such as herpes simplex virus and the common cold has stemmed from these findings; however, there remains much to be learned regarding the antiviral mechanisms and clinical benefit of zinc supplementation as a preventative and therapeutic treatment for viral infections.

Micronutrient Deficiencies in Medical and Surgical Inpatients

Inpatients are threatened by global malnutrition, but also by specific micronutrient (i.e., trace element and vitamins) deficiencies that frequently are overseen in the differential diagnosis of major organ dysfunctions. Some of them are related to specific geographic risks (iodine, iron, selenium, zinc, vitamin A), while others are pathology related, and finally many are associated with specific feeding patterns, including low dose enteral feeding. Among the pathologies in which laboratory blood investigations should include a micronutrient outwork, anemia is in the front line, followed by obesity with bariatric surgery, chronic liver disease, kidney disease, inflammatory bowel disease, cardiomyopathies and heart failure. The micronutrients at the highest risk are iron, zinc, thiamine, vitamin B12 and vitamin C. Admission to hospital has been linked with an additional risk of malnutrition—feeding below 1500 kcal/day was frequent and has been associated with a structural additional risk of insufficient micronutrient intake to cover basal needs. Although not evidence based, systematic administration of liberal thiamine doses upon admission, and daily complementation of inpatients’ food and enteral feeding solutions with multi-micronutrient tablets might be considered.

The antiviral role of zinc and metallothioneins in hepatitis C infection

Metallothioneins (MTs) are small, cysteine-rich proteins characterized by a high affinity for monovalent and divalent cations, such as copper and zinc. Of the four known MT isoforms, only, members of the MT 1 and 2 subfamilies are widely expressed, acting as metal chaperones whose primary role is to mediate intracellular zinc homoeostasis. Metallothioneins are potently induced by heavy metals and other sources of oxidative stress where they facilitate metal binding and detoxification as well as free radical scavenging. Metallothionein expression is well documented in the context of viral infection; however, it remains uncertain whether MTs possess specific antiviral roles or whether induction is merely a consequence of cellular stress. To better understand the role of MTs following hepatitis C virus (HCV) infection, we examined MT expression and localization in vitro and in vivo and used a siRNA knockdown approach to ascertain their antiviral efficacy. We confirmed HCV-driven MT induction in vitro and demonstrated MT accumulation in the nucleus of HCV-infected hepatocytes by immunofluorescence. Using a pan-MT siRNA to knock down all members of the MT1 and MT2 subfamilies, we demonstrate that they are mildly antiviral against the JFH1 strain of HCV in vitro (~1.4 fold increase in viral RNA, P < .05). Furthermore, the antiviral effect of zinc treatment against HCV in vitro was mediated through MT induction (P < .05). Our data suggest a potential benefit of using zinc as a low-cost adjunct to current HCV antiviral therapies and suggest that zinc may facilitate the antiviral role of MTs against other viruses.

Zinc and Selenium Co-supplementation Reduces Some Lipid Peroxidation and Angiogenesis Markers in a Rat Model of NAFLD-Fed High Fat Diet

Studies have shown that non-alcoholic fatty liver disease (NAFLD) patients are more prone to cardiovascular disease (CVD). Zinc and selenium deficiency are common in NAFLD. But the effects of zinc and selenium co-supplementation before and/or after disease progression on CVD markers are not clear in NAFLD patients. This study aimed to compare the effects of zinc and selenium co-supplementation before and/or after disease progression on some of the CVD markers in an experimental model of NAFLD. Forty male Sprague Dawley rats (197 ± 4 g) were randomly assigned into four dietary groups: control group (C; received 9% of calorie as fat), model group (M; received 82% of calorie as fat), and supplementation before (BS) or after (AS) disease progression. Animals were fed diets for 20 weeks in all groups. Fasting plasma glucose (FPG), insulin, HOMA-IR, ALT, AST, lipid profile, malondialdehyde (MDA) and vascular endothelial growth factor (VEGF) levels were measured as CVD indices. Serum ALT, AST, FPG, insulin, MDA, VEGF and HOMA-IR were significantly higher in the M than C group. Co-supplementation reduced serum ALT and AST levels in the BS and AS groups compared with the M group. FPG, insulin, HOMA-IR, VEGF, MDA, LDL/HDL-c and TC/HDL-c ratio were significantly reduced in the AS compared with the M group. TG/HDL-c ratio was significantly reduced in the BS and AS compared with the M group. Serum MDA, VEGF, Insulin and HOMA-IR were significantly lowered in the AS than BS group (p < 0.05). Zinc and selenium co-supplementation after NAFLD progression reduced CVD risk indices in an experimental model.

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

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

Zinc in Infection and Inflammation

Micronutrient homeostasis is a key factor in maintaining a healthy immune system. Zinc is an essential micronutrient that is involved in the regulation of the innate and adaptive immune responses. The main cause of zinc deficiency is malnutrition. Zinc deficiency leads to cell-mediated immune dysfunctions among other manifestations. Consequently, such dysfunctions lead to a worse outcome in the response towards bacterial infection and sepsis. For instance, zinc is an essential component of the pathogen-eliminating signal transduction pathways leading to neutrophil extracellular traps (NET) formation, as well as inducing cell-mediated immunity over humoral immunity by regulating specific factors of differentiation. Additionally, zinc deficiency plays a role in inflammation, mainly elevating inflammatory response as well as damage to host tissue. Zinc is involved in the modulation of the proinflammatory response by targeting Nuclear Factor Kappa B (NF-κB), a transcription factor that is the master regulator of proinflammatory responses. It is also involved in controlling oxidative stress and regulating inflammatory cytokines. Zinc plays an intricate function during an immune response and its homeostasis is critical for sustaining proper immune function. This review will summarize the latest findings concerning the role of this micronutrient during the course of infections and inflammatory response and how the immune system modulates zinc depending on different stimuli.

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.​​​

Serum Zinc and Haptoglobin in Noncirrhotic Azeri Patients with Chronic Active Hepatitis C: a Case-Control Study

The aim of present study was to compare levels of serum zinc and haptoglobin between patients with chronic active hepatitis C and controls. Two groups including Azeri patients with chronic active hepatitis C (n = 274) and their healthy family members (n = 100) were studied. Serum zinc and haptoglobin were measured using colorimetric and nephelometric methods, respectively. Patients were 156 males (56.9%) and 118 females (43.1%) with the mean age of 40.15 ± 12.24 years. Controls were 56 males (56%) and 44 females (44%) with the mean age of 39.32 ± 4.40 (p = 0.87 for sex and 0.51 for age). Both the mean levels of serum zinc (72.04 ± 19.08 vs. 106.18 ± 25.52 μg/dL) and haptoglobin (0.72 ± 0.45 vs. 1.08 ± 0.34 g/L) were significantly lower in patients than in controls (p < 0.001 for both comparisons). Serum zinc concentration was significantly higher in males and did not correlate significantly with age, serum glutamic pyruvic transaminase (SGPT), or serum glutamic oxaloacetic transaminase (SGOT). Serum haptoglobin did not differ significantly between males and females, and it correlated significantly with age (r = -0.20), serum SGPT (r = -0.22), and SGOT (r = -0.20). This study showed lower levels of serum zinc and haptoglobin in patients with chronic hepatitis C than in controls. Major confounding factors in previous studies were left out.

Effect of zinc supplementation on viral response in patients with chronic hepatitis C and Beta thalassemia major, a pilot study

INTRODUCTION

Zinc deficiency has been reported in patients with both hepatitis C and beta thalassemia major. Zinc supplementation in addition to antiviral therapy of chronic hepatitis C has been accompanied by some success in patients with chronic hepatitis C.

OBJECTIVE

The aim of the present pilot study is to determine the effect of 30 mg elemental zinc on biochemical and virological response in a population of patients with chronic hepatitis C with beta thalassemia major.

MATERIALS AND METHODS

A prospective, double blind,placebo controlled trial included 40 patients being treated with Pegylated interferon Alfa (Peg IFN-α) and ribavirin. Biochemical and virological parameters and plasma zinc levels were determined before starting treatment. Patients were randomly selected to receive either zinc or a placebo in addition to Peg IFN-α and ribavirin for a period of one year. AST, ALT, sustained viral response (SVR), and zinc levels were measured after treatment.Of the original 40 eligible patients, eight withdrawn from the study and 32 patients completed the study; 16 in the zinc group and 16 in the placebo group. Analysis of the data shows that there is no difference between the two groups in AST, ALT, SVR or zinc level following one year of treatment (p=0.224, p=0.616, p=0.670, p=0.999, respectively).

CONCLUSION

The results of this study indicate that using 30 mg/day elemental zinc did not significantly improve the outcome of treatment in thalassemia patients with chronic hepatitis C. In future studies, we recommend trying higher doses zinc in patients with hepatitis C who had beta thalassemia major.

Mitochondrial dysfunctions and altered metals homeostasis: new weapons to counteract HCV-related oxidative stress

The hepatitis C virus (HCV) infection produces several pathological effects in host organism through a wide number of molecular/metabolic pathways. Today it is worldwide accepted that oxidative stress actively participates in HCV pathology, even if the antioxidant therapies adopted until now were scarcely effective. HCV causes oxidative stress by a variety of processes, such as activation of prooxidant enzymes, weakening of antioxidant defenses, organelle damage, and metals unbalance. A focal point, in HCV-related oxidative stress onset, is the mitochondrial failure. These organelles, known to be the "power plants" of cells, have a central role in energy production, metabolism, and metals homeostasis, mainly copper and iron. Furthermore, mitochondria are direct viral targets, because many HCV proteins associate with them. They are the main intracellular free radicals producers and targets. Mitochondrial dysfunctions play a key role in the metal imbalance. This event, today overlooked, is involved in oxidative stress exacerbation and may play a role in HCV life cycle. In this review, we summarize the role of mitochondria and metals in HCV-related oxidative stress, highlighting the need to consider their deregulation in the HCV-related liver damage and in the antiviral management of patients.

Is zinc concentration in toxic phase plasma related to dengue severity and level of transaminases?

Objective

To determine the relationship between plasma zinc values and the severity of dengue viral infection (DVI) and DVI-caused hepatitis.

Methods

A prospective cohort study was conducted during 2008–2010 in hospitalized children aged <15 years confirmed with DVI. Complete blood count, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and zinc values (mcg/dL) were determined twice: first during the toxic phase (Zn1) and secondly two weeks after recovery (Zn2).

Results

39 patients were enrolled with a mean age of 9.7±3.7 years, and 15/39 diagnosed with dengue shock syndrome (DSS). Zn1 values were lower than Zn2 values [median (IQR): 46.0 (37.0, 58.0) vs 65.0 (58.0, 81.0) mcg/dL, respectively, p <0.01]. Zn1 but not Zn2 values had a negative correlation with AST and ALT (r_s = −0.33, p = 0.04 and r_s = −0.31, p = 0.05, respectively). Patients with DSS had lower Zn1 but not Zn2 values compared with non-DSS patients [median (IQR) Zn1, 38.0 (30.0, 48.0) vs 52.5 (41.2, 58.7), p = 0.02; Zn2, 61.0 (56.0, 88.0) vs 65.0 (59.5, 77.5), respectively, p = 0.76]. Zn1 values showed a decreasing trend across increasing dengue severity groups (p = 0.02). Age <5 years and DVI-associated diarrhea were associated with low Zn1.

Conclusion

Children who had a higher grade of dengue disease severity and liver cell injury had lower Zn1 values. Low Zn1 values were probably caused by loss from diarrhea and from zinc translocating to liver cells.

Dengue viral infection (DVI) is endemic in tropical counties and severe DVI is a significant cause of death, especially in children. Increased vascular endothelial permeability during the defervescence stage of DVI leading to plasma leakage plays an important role in dengue disease severity. Zinc is a protective and critical nutrient for maintenance of endothelial integrity, and also functions as an antioxidant and membrane stabilizer. Previous studies have found that zinc supplements in children who had diarrhea and sepsis improved the clinical outcomes. Zinc deficiency is common in school children, the age group that commonly acquires DVI, particularly in developing countries. However, prior to studying the potential benefits of zinc supplementation in DVI, having some baseline information concerning plasma zinc values and their correlation with dengue disease severity is necessary. We performed a prospective cohort study during 2008–2010 in 39 hospitalized children aged <15 years confirmed with DVI, and found that plasma zinc values during the toxic phase of disease showed a decreasing trend across increasing dengue severity groups, and also correlated with liver cell injury. DVI-associated diarrhea was probably a major cause of markedly decreased plasma zinc values. These findings will be useful as background information in further studies of whether zinc supplementation can improve the clinical outcome of DVI.

Status of essential trace minerals and oxidative stress in viral hepatitis C patients with nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) may be an important factor leading to altered trace mineral homeostasis, thereby accelerating the progression of hepatitis C virus (HCV) infection. Our aim was to determine whether NAFLD influenced the status of certain essential trace minerals and oxidative stress in chronic HCV-infected patients.

DESIGN AND METHODS

Blood biochemical parameters were determined in a group of 30 healthy, non-obese, non-diabetic participants (CNL group), and hepatitis C patients without NAFLD (HCV group, n = 30) and with NAFLD (HCV-NAFLD group, n = 32).

RESULTS

Concentrations of thiobarbituric acid reactive substances (TBARS; a measure of oxidative stress), C-reactive protein (CRP), ferritin, aminotransferases, lipid profiles, and insulin metabolism were markedly abnormal in both patient groups than in CNL subjects. Compared to patients in the HCV group, those with HCV-NAFLD group had lower high-density lipoprotein concentrations, higher low-density lipoprotein and homeostasis model assessment-insulin resistance (HOMA-IR) values, disrupted antioxidant enzyme activities, and elevated TBARS concentrations, as well as decreased plasma concentrations of trace minerals zinc (Zn) and selenium (Se) and increased copper (Cu). The alterations in mineral homeostasis were also linked to TBARS, CRP, ferritin, lipoproteins, and HOMA-IR values in the HCV-NAFLD group.

CONCLUSIONS

There is a progressive deterioration in the homeostasis of minerals (Zn, Se, and Cu) in HCV-NAFLD patients, which may reflect greater oxidative stress and inflammation. These results suggest that the disturbance in mineral metabolism by NAFLD has an impact on the effectiveness of treatment for chronic HCV infection.

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 zinc transporter Zip14 influences c-Met phosphorylation and hepatocyte proliferation during liver regeneration in mice

BACKGROUND & AIMS

Zinc homeostasis in cells is maintained through tight regulation of zinc influx, efflux, and distribution to intracellular organelles by zinc transporters. The Zrt-Irt-like protein (ZIP) transporters facilitate zinc influx to the cytosol. Expression of the ZIP family member Zip14 can be induced by inflammatory cytokines, which also initiate liver regeneration. Hepatocyte proliferation is required for liver regeneration. Zinc regulates cell proliferation, tissue growth, and many mitogenic signaling pathways; we investigated its role in hepatocytes.

METHODS

Wild-type and Zip14(-/-) mice that underwent partial hepatectomy (70% of liver removed) were used as models of liver regeneration. We also analyzed AML12 hepatocytes that overexpressed Zip14. Proliferation was assessed with proliferating cell nuclear antigen, CD1, and Ki67 markers and along with assays of zinc content was related to protein tyrosine phosphatase 1B (PTP1B) and extracellular signal-regulated kinase 1/2 signaling.

RESULTS

Zip14 was up-regulated and hepatic zinc content increased during liver regeneration. Increased hepatic zinc inhibited activity of the phosphatase PTP1B and increased phosphorylation of c-Met, which promoted hepatocyte proliferation. AML12 cells that overexpressed Zip14 increased in zinc content and proliferation; PTP1B was inhibited and phosphorylation of c-Met increased. The increases in hepatic levels of zinc and hepatocyte proliferation that occurred following partial hepatectomy were not observed in Zip14(-/-) mice.

CONCLUSIONS

The transporter Zip14 mediates hepatic uptake of zinc during liver regeneration and for hepatocyte proliferation. These findings indicate that zinc transporter activity regulates liver tissue growth by sequestering zinc. Reagents that regulate ZIP14 activity might be developed as therapeutics to promote liver regeneration in patients with chronic liver disease.

Antioxidant supplementation attenuates oxidative stress in chronic hepatitis C patients

Reactive oxygen species (ROS) overgeneration is involved in the pathogenesis of hepatitis C. The aim of this study was to evaluate the antioxidant status in the blood of HCV infected patients treated or not with standard therapy before and after supplementation of vitamins E, C and zinc. Biomarkers of oxidative stress were evaluated in the blood of three groups of patients: group 1 - controls; group 2 - HCV patients without treatment examined before and after a daily antioxidant supplementation (vitamin E 800 mg, C 500 mg and zinc 40 mg) for 6 months; and group 3 - HCV patients treated with pegylated interferon combined with ribavirin, also examined before and after the same antioxidant supplementation. Before antiviral treatment HCV patients showed enhanced superoxide dismutase, catalase and glutathione peroxidase activities and decreased glutathione reductase activity, while lipoperoxidation was increased and reduced glutathione showed decreased levels compared to controls. Treatment with standard therapy enhanced the activities of catalase and glutathione S-transferase, increased contents of protein carbonyl and promoted further reduced glutathione depletion. After antioxidant supplementation, decreased catalase and glutathione S-transferase activities, decreased lipoperoxidation in group 2, and increased reduced glutathione contents in both supplemented groups were detected. Before antioxidant supplementation, alanine aminotransferase and gamma glutamyl transferase contents showed significant increases in group 2.

CONCLUSION

Untreated HCV patients and also those treated with the standard therapy are coping with a systemic oxidative stress. The antioxidant supplementation conferred an antioxidant protection to both supplemented groups attenuating oxidation processes related to the disease.

Trace metal imbalance associated with oxidative stress and inflammatory status in anti-hepatitis C virus antibody positive subjects

Toxic and essential trace metals, oxidative stress, and inflammatory status were evaluated in anti-hepatitis C virus (HCV) antibody-positive subjects. Blood biochemical parameters were determined in anti-HCV antibody-positive (n=17) and -negative controls (n=46). Compared with controls, anti-HCV antibody-positive individuals had significantly lower concentrations of plasma zinc (Zn); higher copper (Cu), iron (Fe), lead (Pb), cadmium (Cd), and aluminum (Al); and lower activities of erythrocyte antioxidant enzymes glutathione peroxidase and catalase, and elevated superoxide dismutase. Significantly increased lipid peroxidation malondialdehyde (MDA), and inflammatory markers such as alanine aminotransferase (ALT), high sensitivity C-reactive protein (hs-CRP), ferritin, and Cu/Zn ratios, as well as decreased albumin and high density lipoprotein (HDL) concentrations were observed. We have found significant interactions between toxic (e.g., Pb, Cd, and Al) and essential metals (e.g., Zn, Cu, Fe), which correlated with MDA. In conclusion, anti-HCV antibody-positive subjects had abnormal distributions of trace metals that may aggravate oxidative stress and inflammation, and exacerbate hepatic damage.

Zinc and liver disease

Zinc is an essential trace element required for normal cell growth, development, and differentiation. It is involved in DNA synthesis, RNA transcription, and cell division and activation. It is a critical component in many zinc protein/enzymes, including critical zinc transcription factors. Zinc deficiency/altered metabolism is observed in many types of liver disease, including alcoholic liver disease (ALD) and viral liver disease. Some of the mechanisms for zinc deficiency/altered metabolism include decreased dietary intake, increased urinary excretion, activation of certain zinc transporters, and induction of hepatic metallothionein. Zinc deficiency may manifest itself in many ways in liver disease, including skin lesions, poor wound healing/liver regeneration, altered mental status, or altered immune function. Zinc supplementation has been documented to block/attenuate experimental ALD through multiple processes, including stabilization of gut-barrier function, decreasing endotoxemia, decreasing proinflammatory cytokine production, decreasing oxidative stress, and attenuating apoptotic hepatocyte death. Clinical trials in human liver disease are limited in size and quality, but it is clear that zinc supplementation reverses clinical signs of zinc deficiency in patients with liver disease. Some studies suggest improvement in liver function in both ALD and hepatitis C following zinc supplementation, and 1 study suggested improved fibrosis markers in hepatitis C patients. The dose of zinc used for treatment of liver disease is usually 50 mg of elemental zinc taken with a meal to decrease the potential side effect of nausea.

Antioxidants as therapeutic agents for liver disease

Oxidative stress is commonly associated with a number of liver diseases and is thought to play a role in the pathogenesis of chronic hepatitis C, alcoholic liver disease, non-alcoholic steatohepatitis (NASH), haemochromatosis and Wilson's disease. Antioxidant therapy has thus been considered to have the possibility of beneficial effects in the management of these liver diseases. Despite this promise, antioxidants have produced mixed results in a number of clinical trials of efficacy. This review summarizes the results of clinical trials of antioxidants as sole or adjuvant therapy of chronic hepatitis C, alcoholic liver disease and non-alcoholic steatohepatitis (NASH). Overall, the most promising results to date are for vitamin E therapy of NASH but some encouraging results have been obtained with antioxidant therapy of acute alcoholic hepatitis as well. Despite evidence for small reductions of serum alanine aminotransferase, there is as yet no convincing evidence that antioxidant therapy itself is beneficial to patients with chronic hepatitis C. Problems such as small sample size, short follow up duration, inadequate endpoints, failure to demonstrate tissue delivery and antioxidant efficacy, and heterogeneous nature of the 'antioxidant' compounds used have complicated interpretation of results of the clinical studies. These limitations and their implications for future trial design are discussed.

Coinfection with hepatitis C virus, oxidative stress and antioxidant status in HIV-positive drug users in Miami

BACKGROUND

The pathogenesis of HIV/hepatitis C virus (HCV) coinfection is poorly understood. We examined markers of oxidative stress, plasma antioxidants and liver disease in HIV/HCV-coinfected and HIV-monoinfected adults.

METHODS

Demographics, medical history, and proof of infection with HIV, hepatitis A virus (HAV), hepatitis B virus (HBV) and HCV were obtained. HIV viral load, CD4 cell count, complete blood count (CBC), complete metabolic panel, lipid profile, and plasma concentrations of zinc, selenium, and vitamins A and E were determined. Malondialdehyde (MDA) and glutathione peroxidase concentrations were obtained as measures of oxidative stress. Aminotransferase to platelet ratio index (APRI) and fibrosis index (FIB-4) markers were calculated.

RESULTS

Significant differences were found between HIV/HCV-coinfected and HIV-monoinfected participants in levels of alanine aminotransferase (ALT) (mean±standard deviation: 51.4±50.6 vs. 31.9±43.1 U/L, respectively; P=0.014), aspartate aminotransferase (AST) (56.2±40.9 vs. 34.4±30.2 U/L; P<0.001), APRI (0.52±0.37 vs. 0.255±0.145; P=0.0001), FIB-4 (1.64±.0.91 vs. 1.03±0.11; P=0.0015) and plasma albumin (3.74±0.65 vs. 3.94±0.52 g/dL; P=0.038). There were no significant differences in CD4 cell count, HIV viral load or antiretroviral therapy (ART) between groups. Mean MDA was significantly higher (1.897±0.835 vs. 1.344± 0.223 nmol/mL, respectively; P=0.006) and plasma antioxidant concentrations were significantly lower [vitamin A, 39.5 ± 14.1 vs. 52.4±16.2 μg/dL, respectively (P=0.0004); vitamin E, 8.29±2.1 vs. 9.89±4.5 μg/mL (P=0.043); zinc, 0.61±0.14 vs. 0.67±0.15 mg/L (P=0.016)] in the HIV/HCV-coinfected participants than in the HIV-monoinfected participants, and these differences remained significant after adjusting for age, gender, CD4 cell count, HIV viral load, injecting drug use and race. There were no significant differences in glutathione peroxidase concentration, selenium concentration, body mass index (BMI), alcohol use or tobacco use between groups. Glutathione peroxidase concentration significantly increased as liver disease advanced, as measured by APRI (β=0.00118; P=0.0082) and FIB-4 (β=0.0029; P=0.0177). Vitamin A concentration significantly decreased (β=-0.00581; P=0.0417) as APRI increased.

CONCLUSION

HIV/HCV coinfection is associated with increased oxidative stress and decreased plasma antioxidant concentrations compared with HIV monoinfection. Research is needed to determine whether antioxidant supplementation delays liver disease in HIV/HCV coinfection.

A pilot study to investigate the treatment of cervical human papillomavirus infection with zinc-citrate compound (CIZAR®)

OBJECTIVE

In the present study the potential therapeutic effects of zinc-citrate compound (CIZAR®) in women infected with high-risk human papillomavirus (HR-HPV) was investigated.

METHODS

A total of 194 women diagnosed with HR-HPV infection using the Hybrid capture (HC) II assay with no evidence of high grade squamous intraepithelial lesions (HSIL) or worse by Pap smear and colposcopy were enrolled. Among them, 76 women were treated by twice weekly self administered intra-vaginal infusion of 0.5 mM zinc citrate solution containing CIZAR® for 12 weeks and were evaluated for clearance of the HR-HPV infection compared to 118 women without treatment (Control group).

RESULTS

The 12 weeks zinc citrate solution treatment resulted in the elimination of HR-HPV in 49/76 (64.47%) patients compared to the spontaneous clearance of 15.25% (18/118) in the control group (p=0.000). By logistic regression analysis, the 12 week zinc citrate solution treatment reduced the risk of persistent HR-HPV infection significantly (OR 0.079; 95% CI 0.039-0.165; p=0.000).

CONCLUSION

The results of this study showed for the first time that treatment with intra-vaginal infusion of a zinc-citrate compound (CIZAR®) can result in elimination of HR-HPV infection from the uterine cervix.