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Cilliers K, Muller CJF. Effect of Human Immunodeficiency Virus on Trace Elements in the Brain. Biol Trace Elem Res 2021; 199:41-52. [PMID: 32239375 DOI: 10.1007/s12011-020-02129-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 03/23/2020] [Indexed: 11/27/2022]
Abstract
Comorbidities of human immunodeficiency virus (HIV) include HIV-associated neurocognitive disorder (HAND). Changes in the brain due to HIV include atrophy, hyperintensities, and diffusion changes. However, no research has focused on trace elements concentration changes in the brain due to HIV, as seen in other neurodegenerative diseases. Therefore, the aim of this study was to determine the concentration of several trace elements in the brains of individuals with and without HIV infection. Prior to formalin embalming, blood was drawn and tested in triplicate with Determine HIV-1/2 rapid tests and confirmed with a SD HIV Device 1/2 3.0 rapid HIV Kit. After embalming, tissue was sampled from the caudate nucleus and analyzed using inductively coupled plasma mass spectrometry. A Kruskal-Wallis test was used to determine statistically significant differences between the two groups (p < 0.05). Fifteen HIV-positive and 14 HIV-negative male cadavers were included (mean age 44, range 22 to 61). Cadmium was marginally decreased, possibly due to malnutrition or utilization by the HIV nucleocapsid. Nickel was marginally increased, perhaps due to a reduced capability to remove metals from the body. In conclusion, this article provides the first information on trace element levels in the brains from HIV-infected individuals and postulates that cadmium and nickel may play a role in the pathophysiology of HAND. This information can contribute to finding a treatment for HAND, other than the use of antiretroviral drugs. Future studies should asses the levels of cadmium and nickel in a larger cohort of HIV-infected individuals.
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Affiliation(s)
- Karen Cilliers
- Division of Clinical Anatomy, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, Western Cape, South Africa.
| | - Christo J F Muller
- Biomedical Research and Innovation Platform (BRIP), South African Medical Research Council, Tygerberg, Western Cape, South Africa
- Division of Medical Physiology, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, Western Cape, South Africa
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2
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Vardhana SA, Wolchok JD. The many faces of the anti-COVID immune response. J Exp Med 2020; 217:e20200678. [PMID: 32353870 PMCID: PMC7191310 DOI: 10.1084/jem.20200678] [Citation(s) in RCA: 384] [Impact Index Per Article: 76.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 04/27/2020] [Accepted: 04/27/2020] [Indexed: 01/08/2023] Open
Abstract
The novel 2019 strain of coronavirus is a source of profound morbidity and mortality worldwide. Compared with recent viral outbreaks, COVID-19 infection has a relatively high mortality rate, the reasons for which are not entirely clear. Furthermore, treatment options for COVID-19 infection are currently limited. In this Perspective, we explore the contributions of the innate and adaptive immune systems to both viral control as well as toxicity during COVID-19 infections and offer suggestions to both understand and therapeutically modulate anti-COVID immunity.
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Affiliation(s)
- Santosha A. Vardhana
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY
- Center for Epigenetics Research, Memorial Sloan Kettering Cancer Center, New York, NY
- Parker Institute for Cancer Immunotherapy, San Francisco, CA
| | - Jedd D. Wolchok
- Parker Institute for Cancer Immunotherapy, San Francisco, CA
- Human Oncology Pathogenesis Program, Department of Medicine and Ludwig Center, Memorial Sloan Kettering Cancer Center, New York, NY
- Weill Cornell Medicine and Graduate School of Biomedical Sciences, New York, NY
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3
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Vardhana SA, Wolchok JD. The many faces of the anti-COVID immune response. THE JOURNAL OF EXPERIMENTAL MEDICINE 2020. [PMID: 32353870 DOI: 10.1084/jem.20200678.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The novel 2019 strain of coronavirus is a source of profound morbidity and mortality worldwide. Compared with recent viral outbreaks, COVID-19 infection has a relatively high mortality rate, the reasons for which are not entirely clear. Furthermore, treatment options for COVID-19 infection are currently limited. In this Perspective, we explore the contributions of the innate and adaptive immune systems to both viral control as well as toxicity during COVID-19 infections and offer suggestions to both understand and therapeutically modulate anti-COVID immunity.
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Affiliation(s)
- Santosha A Vardhana
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY.,Center for Epigenetics Research, Memorial Sloan Kettering Cancer Center, New York, NY.,Parker Institute for Cancer Immunotherapy, San Francisco, CA
| | - Jedd D Wolchok
- Parker Institute for Cancer Immunotherapy, San Francisco, CA.,Human Oncology Pathogenesis Program, Department of Medicine and Ludwig Center, Memorial Sloan Kettering Cancer Center, New York, NY.,Weill Cornell Medicine and Graduate School of Biomedical Sciences, New York, NY
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4
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Guillin OM, Vindry C, Ohlmann T, Chavatte L. Selenium, Selenoproteins and Viral Infection. Nutrients 2019; 11:nu11092101. [PMID: 31487871 PMCID: PMC6769590 DOI: 10.3390/nu11092101] [Citation(s) in RCA: 276] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 08/23/2019] [Accepted: 08/27/2019] [Indexed: 02/07/2023] Open
Abstract
Reactive oxygen species (ROS) are frequently produced during viral infections. Generation of these ROS can be both beneficial and detrimental for many cellular functions. When overwhelming the antioxidant defense system, the excess of ROS induces oxidative stress. Viral infections lead to diseases characterized by a broad spectrum of clinical symptoms, with oxidative stress being one of their hallmarks. In many cases, ROS can, in turn, enhance viral replication leading to an amplification loop. Another important parameter for viral replication and pathogenicity is the nutritional status of the host. Viral infection simultaneously increases the demand for micronutrients and causes their loss, which leads to a deficiency that can be compensated by micronutrient supplementation. Among the nutrients implicated in viral infection, selenium (Se) has an important role in antioxidant defense, redox signaling and redox homeostasis. Most of biological activities of selenium is performed through its incorporation as a rare amino acid selenocysteine in the essential family of selenoproteins. Selenium deficiency, which is the main regulator of selenoprotein expression, has been associated with the pathogenicity of several viruses. In addition, several selenoprotein members, including glutathione peroxidases (GPX), thioredoxin reductases (TXNRD) seemed important in different models of viral replication. Finally, the formal identification of viral selenoproteins in the genome of molluscum contagiosum and fowlpox viruses demonstrated the importance of selenoproteins in viral cycle.
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Affiliation(s)
- Olivia M Guillin
- CIRI, Centre International de Recherche en Infectiologie, CIRI, 69007 Lyon, France
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unité U1111, 69007 Lyon, France
- Ecole Normale Supérieure de Lyon, 69007 Lyon, France
- Université Claude Bernard Lyon 1 (UCBL1), 69622 Lyon, France
- Unité Mixte de Recherche 5308 (UMR5308), Centre national de la recherche scientifique (CNRS), 69007 Lyon, France
| | - Caroline Vindry
- CIRI, Centre International de Recherche en Infectiologie, CIRI, 69007 Lyon, France
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unité U1111, 69007 Lyon, France
- Ecole Normale Supérieure de Lyon, 69007 Lyon, France
- Université Claude Bernard Lyon 1 (UCBL1), 69622 Lyon, France
- Unité Mixte de Recherche 5308 (UMR5308), Centre national de la recherche scientifique (CNRS), 69007 Lyon, France
| | - Théophile Ohlmann
- CIRI, Centre International de Recherche en Infectiologie, CIRI, 69007 Lyon, France
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unité U1111, 69007 Lyon, France
- Ecole Normale Supérieure de Lyon, 69007 Lyon, France
- Université Claude Bernard Lyon 1 (UCBL1), 69622 Lyon, France
- Unité Mixte de Recherche 5308 (UMR5308), Centre national de la recherche scientifique (CNRS), 69007 Lyon, France
| | - Laurent Chavatte
- CIRI, Centre International de Recherche en Infectiologie, CIRI, 69007 Lyon, France.
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unité U1111, 69007 Lyon, France.
- Ecole Normale Supérieure de Lyon, 69007 Lyon, France.
- Université Claude Bernard Lyon 1 (UCBL1), 69622 Lyon, France.
- Unité Mixte de Recherche 5308 (UMR5308), Centre national de la recherche scientifique (CNRS), 69007 Lyon, France.
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Bazazzadegan N, Dehghan Shasaltaneh M, Saliminejad K, Kamali K, Banan M, Khorram Khorshid HR. Effects of Herbal Compound (IMOD) on Behavior and Expression of Alzheimer's Disease Related Genes in Streptozotocin-Rat Model of Sporadic Alzheimer's Disease. Adv Pharm Bull 2017; 7:491-494. [PMID: 29071234 PMCID: PMC5651073 DOI: 10.15171/apb.2017.060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 08/29/2017] [Accepted: 08/30/2017] [Indexed: 12/31/2022] Open
Abstract
Purpose: Sporadic Alzheimer’s disease (AD) accounts for over 95% of cases. Possible mechanisms of AD such as inflammation and oxidative stresses in the brain motivate researchers to follow many therapies which would be effective, especially in the early stages of the disease. IMOD, the herbal extract of R. Canina, T. Vulgare and U. Dioica plant species enriched with selenium, has anti-inflammatory, immunoregulatory and protective effects against oxidative stress. Methods: In this study three AD-related genes, DAXX, NFκβ and VEGF, were chosen as candidate to investigate the neuroprotective effect of the extract by comparing their expression levels in the hippocampus of rat model of sporadic AD, using qPCR in the herbal-treated and control groups. The therapeutic effects on learning and memory levels were evaluated by Morris Water Maze (MWM) test. Results: Gene expression results were indicative of significant up-regulation of Vegf in rat’s hippocampus after treatment with the herbal extract comparing to model group (P-value= 0.001). The MWM results showed significant changes in path length and time for finding the hidden platform in all groups during test and the same change in the treated comparing to the control group in memory level. Conclusion: It could be concluded that the herbal extract may have significant effect on gene expression but not on behavioral level.
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Affiliation(s)
- Niloofar Bazazzadegan
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Marzieh Dehghan Shasaltaneh
- Laboratory of Neuro-organic Chemistry, Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | - Kioomars Saliminejad
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Koorosh Kamali
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Mehdi Banan
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
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6
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A randomized, placebo-controlled pilot trial of N-acetylcysteine on oxidative stress and endothelial function in HIV-infected older adults receiving antiretroviral treatment. AIDS 2016; 30:2389-91. [PMID: 27603163 DOI: 10.1097/qad.0000000000001222] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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7
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Hsieh CC, Hsieh SC, Chiu JH, Wu YL. Protective Effects of N-acetylcysteine and a Prostaglandin E1 Analog, Alprostadil, Against Hepatic Ischemia: Reperfusion Injury in Rats. J Tradit Complement Med 2014; 4:64-71. [PMID: 24872935 PMCID: PMC4032844 DOI: 10.4103/2225-4110.124351] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Ischemia–reperfusion (I/R) injury has a complex pathophysiology resulting from a number of contributing factors. Therefore, it is difficult to achieve effective treatment or protection by individually targeting the mediators or mechanisms. Our aim was to analyze the individual and combined effects of N-acetylcysteine (NAC) and the prostaglandin E1 (PGE1) analog alprostadil on hepatic I/R injury in rats. Thirty male Sprague-Dawley rats were randomly divided into five groups (six rats per group) as follows: Control group, I/R group, I/R + NAC group, I/R + alprostadil group, and I/R + NAC + alprostadil group. The rats received injections of NAC (150 mg/kg) and/or alprostadil (0.05 μg/kg) over a period of 30 min prior to ischemia. These rats were then subjected to 60 min of hepatic ischemia followed by a 60-min reperfusion period. Hepatic superoxide dismutase (SOD), catalase, and glutathione levels were significantly decreased as a result of I/R injury, but they were increased in groups treated with NAC. Hepatic malondialdehyde (MDA), myeloperoxidase (MPO), and nitric oxide (NO) activities were significantly increased after I/R injury, but they were decreased in the groups with NAC treatment. Alprostadil decreased NO production, but had no effect on MDA and MPO. Histological results showed that both NAC and alprostadil were effective in improving liver tissue morphology during I/R injury. Although NAC and alprostadil did not have a synergistic effect, our findings suggest that treatment with either NAC or alprostadil has benefits for ameliorating hepatic I/R injury.
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Affiliation(s)
- Cheng-Chu Hsieh
- Department and Institute of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan. ; Biologics Division, Animal Health Research Institute, Council of Agriculture, Executive Yuan, New Taipei, Taiwan
| | - Shu-Chen Hsieh
- Graduate Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Jen-Hwey Chiu
- Division of General Surgery, Department of Surgery, Veterans General Hospital, Taipei, Taiwan. ; Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Ying-Ling Wu
- Department and Institute of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
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8
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Hurst R, Collings R, Harvey LJ, King M, Hooper L, Bouwman J, Gurinovic M, Fairweather-Tait SJ. EURRECA-Estimating selenium requirements for deriving dietary reference values. Crit Rev Food Sci Nutr 2014; 53:1077-96. [PMID: 23952089 DOI: 10.1080/10408398.2012.742861] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Current reference values for selenium, an essential micronutrient, are based on the intake of selenium that is required to achieve maximal glutathione peroxidase activity in plasma or erythrocytes. In order to assess the evidence of relevance to setting dietary reference values for selenium, the EURRECA Network of Excellence focused on systematic searches, review, and evaluation of (i) selenium status biomarkers and evidence for relationships between intake and status biomarkers, (ii) selenium and health (including the effect of intake and/or status biomarkers on cancer risk, immune function, HIV, cognition, and fertility), (iii) bioavailability of selenium from the diet, and (iv) impact of genotype/single nucleotide polymorphisms on status or health outcomes associated with selenium. The main research outputs for selenium and future research priorities are discussed further in this review.
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Affiliation(s)
- Rachel Hurst
- Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK
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9
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Farhoudi M, Najafi-Nesheli M, Hashemilar M, Mahmoodpoor A, Sharifipour E, Baradaran B, Taheraghdam A, Savadi-Oskouei D, Sadeghi-Bazargani H, Sadeghi-Hokmabadi E, Akbari H, Rikhtegar R. Effect of IMOD™ on the inflammatory process after acute ischemic stroke: a randomized clinical trial. ACTA ACUST UNITED AC 2013; 21:26. [PMID: 23514014 PMCID: PMC3620936 DOI: 10.1186/2008-2231-21-26] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 03/10/2013] [Indexed: 12/13/2022]
Abstract
Background and purpose of the study Considering the role of inflammation in acute cerebrovascular accidents, anti-inflammatory treatment has been considered as an option in cerebrovascular diseases. Regarding the properties of Setarud (IMOD™) in immune regulation, the aim of the present study was to evaluate the role of this medication in treating patients with acute ischemic stroke. Methods In this randomized clinical trial, 99 patients with their first ever acute ischemic stroke were divided into two groups of IMOD™ (n = 49) and control (n = 50). The control group underwent routine treatment and the intervention group underwent routine treatment plus daily intermittent infusion of IMOD™ (250mg on the first day and then 375mg into DW5% serum during a 30-minute period for 7 days). The serum levels of inflammatory markers were evaluated on the first day (baseline) and on 4th and 7th days. Data were analyzed and the results were compared. Results and major conclusion 58 males (58.6%) and 41 females (41.4%) with a mean age of 67.00 ± 8.82 years, who had their first ever stroke attack, were enrolled in this trial. Treatment with IMOD™ showed a decreasing trend in IL-6 levels compared to the control group (p = 0.04). In addition, the treatment resulted in the control of increasing serum levels of hsCRP after 7 days compared to the control group (p = 0.02). There was an insignificant decrease in TNF-α and IL-1 levels in the IMOD™ group. Considering the prominent role of inflammation after an ischemic cerebral damage, it appears that treatment with IMOD™ improves the inflammatory profile. Therefore, IMOD™ (Setarud) might be considered as a therapeutic option in the acute ischemic stroke. However, future studies are necessary on its long-term results and clinical efficacy.
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Affiliation(s)
- Mehdi Farhoudi
- Neuroscience Research Center (NSRC), Imam Reza Hospital, Tabriz University of Medical Sciences, Tabriz, Iran.
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Chang W, Barve S, Chen TS. p-Aminophenol-induced cytotoxicity in Jurkat T cells: protective effect of 2(RS)-n-propylthiazolidine-4(R)-carboxylic acid. J Biochem Mol Toxicol 2011; 26:71-8. [PMID: 22162043 DOI: 10.1002/jbt.20402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 06/03/2011] [Accepted: 06/10/2011] [Indexed: 11/11/2022]
Abstract
Acetaminophen (APAP) is hepatotoxic and can cause toxicity in Jurkat T cells. p-Aminophenol (PAP), an industrial chemical and APAP metabolite, is nephrotoxic and hepatotoxic. Its potential toxicity in Jurkat T cells was investigated. PAP (10-250 µM) caused toxicity (decreased survival and increased LDH activity in incubation medium) and GSH depletion. At a concentration of 100 µM but not 250 µM, PAP increased DNA fragmentation. It decreased p-Akt levels (Elisa) and at higher concentrations decreased p-Akt expression (Western blotting). It had no effect on FasL expression. The cysteine precursor 2(RS)-n-propylthiazolidine-4(R)-carboxylic acid (250 µM) attenuated the PAP (100 µM)-induced decrease in viability and prevented GSH depletion and increased DNA fragmentation. It attenuated the PAP-induced decrease in p-Akt levels and protected against the decrease in p-Akt expression. The results demonstrate PAP-induced toxicity and suggest that it is due at least in part to apoptosis and involves GSH depletion and p-Akt inactivation.
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Affiliation(s)
- Weiyuan Chang
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40292, USA
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Yousefi S, Hadadi A, Ostovar A, Noor BE, Rasoolinejad M, Abdolbaghi MH, Khalili H. Protocol of Determining the Effect of Selenium Supplementation on CD4 + T Lymphocyte Count in HIV/AIDS Patients: A Randomized Double Blind Placebo Controlled Trial. ACTA ACUST UNITED AC 2011. [DOI: 10.4236/aid.2011.12003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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de Pee S, Semba RD. Role of Nutrition in HIV Infection: Review of Evidence for more Effective Programming in Resource-Limited Settings. Food Nutr Bull 2010. [DOI: 10.1177/15648265100314s403] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Background HIV infection and malnutrition negatively reinforce each other. Objective For program guidance, to review evidence on the relationship of HIV infection and malnutrition in adults in resource-limited settings. Results and conclusions Adequate nutritional status supports immunity and physical performance. Weight loss, caused by low dietary intake (loss of appetite, mouth ulcers, food insecurity), malabsorption, and altered metabolism, is common in HIV infection. Regaining weight, particularly muscle mass, requires antiretroviral therapy (ART), treatment of opportunistic infections, consumption of a balanced diet, physical activity, mitigation of side effects, and perhaps appetite stimulants and growth hormone. Correcting nutritional status becomes more difficult as infection progresses. Studies document widespread micronutrient deficiencies among HIV-infected people. However, supplement composition, patient characteristics, and treatments vary widely across intervention studies. Therefore, the World Health Organization (WHO) recommends ensuring intake of 1 Recommended Nutrient Intake (RNI) of each required micronutrient, which may require taking micronutrient supplements. Few studies have assessed the impact of food supplements. Because the mortality risk in patients receiving ART increases with lower body mass index (BMI), improving the BMI seems important. Whether this requires provision of food supplements depends on the patient's diet and food security. It appears that starting ART improves BMI and that ready-to-use fortified spreads and fortified-blended foods further increase BMI (the effect is somewhat less with fortified-blended foods). The studies are too small to assess effects on mortality. Once ART has been established and malnutrition treated, the nutritional quality of the diet remains important, also because of ART's long-term metabolic effects (dyslipidemia, insulin resistance, obesity). Food insecurity should also be addressed if it prevents adequate energy intake and reduces treatment initiation and adherence (due to the opportunity costs of obtaining treatment and mitigating side effects).
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13
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Bella SD, Grilli E, Cataldo MA, Petrosillo N. Selenium deficiency and HIV infection. Infect Dis Rep 2010; 2:e18. [PMID: 24470898 PMCID: PMC3892587 DOI: 10.4081/idr.2010.e18] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 11/15/2010] [Accepted: 11/23/2010] [Indexed: 12/31/2022] Open
Abstract
Selenium is a non-metallic chemical element of great important to human health. Low selenium levels in humans are associated with several pathological conditions and are a common finding in HIV infected individuals. We conducted a review of the literature to assess if selenium deficiency or selenium supplementation could play a role in modifying the clinical course of HIV disease. Several studies investigated the role of selenium in disease progression, morbidity and mortality in HIV infected individuals. Larger studies were conducted in countries with poor economic resources and limited access to HAART. According to the majority of published studies low selenium levels appear to have an association with mortality, and selenium supplementation appears to play a beneficial role on survival or on slowing disease progression among HIV infected individuals. The role of selenium supplementation on preventing hospital admission among HIV outpatients was also noticed. The literature suggests an association between selenium deficiency and development of HIV associated cardiomyopathy and furthermore, selenium supplementation appears to improve the cardiac function in HIV infected individuals with cardiomyopathy. However, there is conflicting evidence regarding the role selenium in modifying HIV viral load and immune status in HIV infection.
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Affiliation(s)
| | | | | | - Nicola Petrosillo
- National Institute for Infectious Diseases “L. Spallanzani”, Rome, Italy
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Hummelen R, Hemsworth J, Reid G. Micronutrients, N-acetyl cysteine, probiotics and prebiotics, a review of effectiveness in reducing HIV progression. Nutrients 2010; 2:626-51. [PMID: 22254046 PMCID: PMC3257666 DOI: 10.3390/nu2060626] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 05/18/2010] [Accepted: 05/25/2010] [Indexed: 01/24/2023] Open
Abstract
Low serum concentrations of micronutrients, intestinal abnormalities, and an inflammatory state have been associated with HIV progression. These may be ameliorated by micronutrients, N-acetyl cysteine, probiotics, and prebiotics. This review aims to integrate the evidence from clinical trials of these interventions on the progression of HIV. Vitamin B, C, E, and folic acid have been shown to delay the progression of HIV. Supplementation with selenium, N-acetyl cysteine, probiotics, and prebiotics has considerable potential, but the evidence needs to be further substantiated. Vitamin A, iron, and zinc have been associated with adverse effects and caution is warranted for their use.
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Affiliation(s)
- Ruben Hummelen
- Department of Public Health, Erasmus MC University Medical Center Rotterdam P.O. Box 2040, 3000 CA Rotterdam, The Netherlands;
- Canadian Research & Development Centre for Probiotics, Lawson Health Research Institute, 268 Grosvenor Street, N6A 4V2, London, Ontario, Canada
| | - Jaimie Hemsworth
- Division of Food and Nutritional Sciences at Brescia University College, The University of Western Ontario, 1285 Western Road, N6G 1H2, London, Ontario, Canada;
| | - Gregor Reid
- Canadian Research & Development Centre for Probiotics, Lawson Health Research Institute, 268 Grosvenor Street, N6A 4V2, London, Ontario, Canada
- Departments of Microbiology & Immunology and Surgery, The University of Western Ontario, 1151 Richmond Street, N6A 3K7, London, Ontario, Canada
- Author to whom correspondence should be addressed; ; Tel.: 519-646-6100 x65256
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15
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Pitney CL, Royal M, Klebert M. Selenium supplementation in HIV-infected patients: is there any potential clinical benefit? J Assoc Nurses AIDS Care 2009; 20:326-33. [PMID: 19576549 DOI: 10.1016/j.jana.2009.03.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Accepted: 03/10/2009] [Indexed: 11/25/2022]
Abstract
In HIV-infected patients undergoing antiretroviral therapy, the question of whether selenium supplementation has any therapeutic benefit is still open. With recent popular coverage of this issue, many patients have considered using selenium. Clinicians have a duty to ensure that the recommendations they make to their patients are evidence based. The literature search reported here showed that evidence to support standard selenium supplementation in patients with HIV is both limited and insufficient. To definitively answer this clinical question, the overall effect of selenium supplementation would need to be evaluated in a large randomized, controlled trial with solid methodology and strong internal validity. Although the available evidence for selenium supplementation is weak, its low toxicity and side effect profile seem to pose minimal risks, especially at low doses. For patients who want to add selenium to their regimen, discussing the potential risks and benefits as well as close follow-up is warranted.
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16
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Guijarro LG, Mate J, Gisbert JP, Perez-Calle JL, Marín-Jimenez I, Arriaza E, Olleros T, Delgado M, Castillejo MS, Prieto-Merino D, Lara VG, Peña AS. N-acetyl-L-cysteine combined with mesalamine in the treatment of ulcerative colitis: Randomized, placebo-controlled pilot study. World J Gastroenterol 2008; 14:2851-7. [PMID: 18473409 PMCID: PMC2710726 DOI: 10.3748/wjg.14.2851] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To evaluate the effectiveness and safety of oral N-acetyl-L-cysteine (NAC) co-administration with mesalamine in ulcerative colitis (UC) patients.
METHODS: Thirty seven patients with mild to moderate UC were randomized to receive a four-wk course of oral mesalamine (2.4 g/d) plus N-acetyl-L-cysteine (0.8 g/d) (group A) or mesalamine plus placebo (group B). Patients were monitored using the Modified Truelove-Witts Severity Index (MTWSI). The primary endpoint was clinical remission (MTWSI ≤ 2) at 4 wk. Secondary endpoints were clinical response (defined as a reduction from baseline in the MTWSI of ≥ 2 points) and drug safety. The serum TNF-α, interleukin-6, interleukin-8 and MCP-1 were evaluated at baseline and at 4 wk of treatment.
RESULTS: Analysis per-protocol criteria showed clinical remission rates of 63% and 50% after 4 wk treatment with mesalamine plus N-acetyl-L-cysteine (group A) and mesalamine plus placebo (group B) respectively (OR = 1.71; 95% CI: 0.46 to 6.36; P = 0.19; NNT = 7.7). Analysis of variance (ANOVA) of data indicated a significant reduction of MTWSI in group A (P = 0.046) with respect to basal condition without significant changes in the group B (P = 0.735) during treatment. Clinical responses were 66% (group A) vs 44% (group B) after 4 wk of treatment (OR = 2.5; 95% CI: 0.64 to 9.65; P = 0.11; NNT = 4.5). Clinical improvement in group A correlated with a decrease of IL-8 and MCP-1. Rates of adverse events did not differ significantly between both groups.
CONCLUSION: In group A (oral NAC combined with mesalamine) contrarily to group B (mesalamine alone), the clinical improvement correlates with a decrease of chemokines such as MCP-1 and IL-8. NAC addition not produced any side effects.
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17
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Chang W, McClain CJ, Liu MC, Barve SS, Chen TS. Effects of 2(RS)-n-propylthiazolidine-4(R)-carboxylic acid on 4-hydroxy-2-nonenal-induced apoptotic T cell death. J Nutr Biochem 2007; 19:184-92. [PMID: 17618106 DOI: 10.1016/j.jnutbio.2007.02.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Revised: 01/31/2007] [Accepted: 02/06/2007] [Indexed: 12/31/2022]
Abstract
4-Hydroxy-2-nonenal (HNE), the aldehydic product of lipid peroxidation, is associated with multiple immune dysfunctions, such as HIV and hepatitis C virus infection. HNE-induced immunosuppression could be due to a decrease in CD4+ T lymphocyte activation or proliferation. Glutathione (GSH) is the most abundant endogenous antioxidant in cells, and an adduct between HNE and GSH has been suggested to be a marker of oxidative stress. Our earlier studies showed that HNE induced cytotoxicity and Akt inactivation, which led to the enhancement of FasL expression and concomitantly decreased cellular FLICE-like inhibitory protein (c-FLIP(S)) levels. In this study, we found that HNE caused intracellular GSH depletion in Jurkat T cells, and we further investigated the role of 2(RS)-n-propylthiazolidine-4(R)-carboxylic acid (PTCA), a GSH prodrug, in attenuating HNE-induced cytotoxicity in CD4+ T lymphocytes. The results show that PTCA protected against HNE-induced apoptosis and depletion of intracellular GSH. PTCA also suppressed FasL expression through increasing levels of Akt kinase as well as antiapoptotic c-FLIP(S) and decreasing the activation of type 2 protein serine/threonine phosphatase. Taken together, these data demonstrate a novel correlation between GSH levels and Akt activation in T lymphocyte survival, which involves FasL down-regulation and c-FLIP(S) expression through increasing intracellular GSH levels. This suggests that PTCA could potentially be used in the treatment of oxidative stress-induced immunosuppressive diseases.
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Affiliation(s)
- Weiyuan Chang
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40292, USA
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18
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Drain PK, Baeten JM, Overbaugh J, Wener MH, Bankson DD, Lavreys L, Mandaliya K, Ndinya-Achola JO, McClelland RS. Low serum albumin and the acute phase response predict low serum selenium in HIV-1 infected women. BMC Infect Dis 2006; 6:85. [PMID: 16712720 PMCID: PMC1479829 DOI: 10.1186/1471-2334-6-85] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2005] [Accepted: 05/19/2006] [Indexed: 01/24/2023] Open
Abstract
Background Low serum selenium has been associated with lower CD4 counts and greater mortality among HIV-1-seropositive individuals, but most studies have not controlled for serum albumin and the presence of an acute phase response. Methods A cross-sectional study was conducted to evaluate relationships between serum selenium concentrations and CD4 count, plasma viral load, serum albumin, and acute phase response markers among 400 HIV-1-seropositive women. Results In univariate analyses, lower CD4 count, higher plasma viral load, lower albumin, and the presence of an acute phase response were each significantly associated with lower serum selenium concentrations. In multivariate analyses including all four of these covariates, only albumin remained significantly associated with serum selenium. For each 0.1 g/dl increase in serum albumin, serum selenium increased by 0.8 μg/l (p < 0.001). Women with an acute phase response also had lower serum selenium (by 5.6 μg/l, p = 0.06). Conclusion Serum selenium was independently associated with serum albumin, but not with CD4 count or plasma viral load, in HIV-1-seropositive women. Our findings suggest that associations between lower serum selenium, lower CD4 count, and higher plasma viral load may be related to the frequent occurrence of low serum albumin and the acute phase response among individuals with more advanced HIV-1 infection.
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Affiliation(s)
- Paul K Drain
- School of Medicine, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
| | - Jared M Baeten
- Department of Medicine, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
| | - Julie Overbaugh
- Divisions of Human Biology and Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, USA
| | - Mark H Wener
- Department of Medicine, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
- Department of Laboratory Medicine, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
- Clinical Nutrition Research Unit Laboratory Core, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
| | - Daniel D Bankson
- Department of Laboratory Medicine, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
- Clinical Nutrition Research Unit Laboratory Core, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
- Veterans Affairs Puget Sound Health Care System, Seattle, USA
| | - Ludo Lavreys
- Department of Epidemiology, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
- Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya
| | | | | | - R Scott McClelland
- Department of Medicine, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
- Department of Epidemiology, University of Washington, 1959 NE Pacific, A-300 Health Sciences, Box 356340, Seattle, WA 98105, USA
- Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya
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19
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Irlam JH, Visser ME, Rollins N, Siegfried N. Micronutrient supplementation in children and adults with HIV infection. Cochrane Database Syst Rev 2005:CD003650. [PMID: 16235333 DOI: 10.1002/14651858.cd003650.pub2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND The scale and impact of the HIV/AIDS pandemic has made the search for simple, affordable, safe, and effective public health interventions all the more urgent. Micronutrient supplements hold the promise of meeting these criteria, but their widespread use needs to be based on sound scientific evidence of effectiveness and safety. OBJECTIVES To assess whether micronutrient supplements are effective in reducing morbidity and mortality in adults and children with HIV infection. SEARCH STRATEGY The Cochrane Library (CENTRAL), EMBASE, MEDLINE, AIDSearch, CINAHL, and conference proceedings were searched, and pharmaceutical manufacturers and researchers in the field were contacted to locate any ongoing or unpublished trials. SELECTION CRITERIA Randomised controlled trials comparing the effects of micronutrient supplements (vitamins, trace elements, and combinations of these) with placebo or no treatment on mortality and morbidity in HIV-infected individuals. DATA COLLECTION AND ANALYSIS Two reviewers independently appraised trial quality and extracted data. Study authors were contacted for additional data where necessary. A meta-analysis was not deemed appropriate due to significant heterogeneity between trials. MAIN RESULTS Fifteen trials were included. Six trials comparing vitamin A/beta-carotene with placebo in adults failed to show any effects on mortality, morbidity, CD4 and CD8 counts, or on viral load. Four trials of other micronutrients in adults did not affect overall mortality, although there was a reduction in mortality in a low CD4 subgroup. In a large Tanzanian trial in pregnant and lactating women, daily multivitamin supplementation was associated with a number of benefits to both mothers and children: a reduction in maternal mortality from AIDS-related causes; a reduced risk of progression to stage four disease; fewer adverse pregnancy outcomes; less diarrhoeal morbidity; and a reduction in early-child mortality among immunologically- and nutritionally-compromised women. Vitamin A alone reduced all-cause mortality and improved growth in a small sub-group of HIV-infected children in one hospital-based trial, and reduced diarrhoea-associated morbidity in a small HIV-infected sub-group of infants in another trial. AUTHORS' CONCLUSIONS There is no conclusive evidence at present to show that micronutrient supplementation effectively reduces morbidity and mortality among HIV-infected adults. It is reasonable to support the current WHO recommendations to promote and support adequate dietary intake of micronutrients at RDA levels wherever possible. There is evidence of benefit of vitamin A supplementation in children. The long-term clinical benefits, adverse effects, and optimal formulation of micronutrient supplements require further investigation.
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Affiliation(s)
- J H Irlam
- University of Cape Town, Paediatrics and Child Health - Child Health Unit, 46 Sawkins Rd, Rondebosch, Cape Town, South Africa 7700.
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20
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Fawzi W, Msamanga G, Spiegelman D, Hunter DJ. Studies of vitamins and minerals and HIV transmission and disease progression. J Nutr 2005; 135:938-44. [PMID: 15795466 DOI: 10.1093/jn/135.4.938] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
HIV-1 infection is having a devastating impact on people in developing countries. Poor nutrition and HIV-related adverse health outcomes contribute to a vicious cycle that may be slowed down by using nutritional interventions, including vitamins and minerals. Among children, periodic supplementation with vitamin A starting at 6 mo of age has been shown to be beneficial in reducing mortality and morbidity among both HIV-infected and uninfected children. Limited data exist on the role of other nutrient supplements among children. Among HIV-infected adults, the safety and the efficacy of vitamin A supplements need further study, although adequate dietary intake of this essential nutrient is recommended. Multivitamin supplements were efficacious in reducing adverse pregnancy outcomes and early childhood infections, and is currently provided to pregnant HIV-infected pregnant women in many programs. The efficacy of such supplements among HIV-negative pregnant women needs further study. Daily multivitamin supplements were found to reduce HIV disease progression among men and women in several observational studies and randomized trials, and to provide an important low-cost intervention that could be provided to adults in early stages of HIV disease to prolong the time before antiretroviral therapy is recommended. Next, research priorities include examining the roles of minerals, including selenium, in HIV infection, as well as determining the safety and the efficacy of micronutrient supplements among individuals who are advanced in their disease and who are receiving antiretroviral therapy.
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Affiliation(s)
- Wafaie Fawzi
- Department of Nutrition, Harvard School of Public Health, Boston, MA, USA.
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21
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McClelland RS, Baeten JM, Overbaugh J, Richardson BA, Mandaliya K, Emery S, Lavreys L, Ndinya-Achola JO, Bankson DD, Bwayo JJ, Kreiss JK. Micronutrient Supplementation Increases Genital Tract Shedding of HIV-1 in Women. J Acquir Immune Defic Syndr 2004; 37:1657-63. [PMID: 15577425 DOI: 10.1097/00126334-200412150-00021] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To test the hypothesis that micronutrient supplementation decreases genital HIV-1 shedding, a double-blind, randomized, placebo-controlled trial of 6 weeks of multivitamin plus selenium supplementation vs. placebo was conducted among 400 HIV-1-seropositive, nonpregnant, antiretroviral-naive women in Mombasa, Kenya. Primary outcome measures included cervical and vaginal shedding of HIV-1-infected cells and RNA. Secondary outcomes included plasma viral load and CD4 count. Surprisingly, the odds of detection of vaginal HIV-1-infected cells were 2.5-fold higher (P = 0.001) and the quantity of HIV-1 RNA in vaginal secretions was 0.37 log10 copies/swab higher (P = 0.004) among women who received micronutrients in comparison to placebo, even after adjustment for potential confounders including baseline HIV-1 shedding and CD4 count. The increase in vaginal HIV-1 shedding was greatest among women who had normal baseline selenium levels. Micronutrient supplementation resulted in higher CD4 (+23 cells/microL, P = 0.03) and CD8 (+74 cells/microL, P = 0.005) counts compared with placebo but did not alter the plasma viral load. In this randomized trial, micronutrients resulted in higher levels of genital HIV-1 shedding compared with placebo. The potential benefit of micronutrient supplementation in HIV-1-seropositive women should be considered in relation to the potential for increased infectivity.
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Affiliation(s)
- R Scott McClelland
- Department of Medicine, University of Washington, Seattle, WA 98104, USA.
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22
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Kupka R, Msamanga GI, Spiegelman D, Morris S, Mugusi F, Hunter DJ, Fawzi WW. Selenium status is associated with accelerated HIV disease progression among HIV-1-infected pregnant women in Tanzania. J Nutr 2004; 134:2556-60. [PMID: 15465747 DOI: 10.1093/jn/134.10.2556] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Selenium deficiency has been implicated in accelerated disease progression and poorer survival among populations infected with HIV in developed countries, yet these associations remain unexamined in developing countries. Among 949 HIV-1-infected Tanzanian women who were pregnant, we prospectively examined the association between plasma selenium levels and survival and CD4 counts over time. Over the 5.7-y median follow-up time, 306 of 949 women died. In a Cox multivariate model, lower plasma selenium levels were significantly associated with an increased risk of mortality (P-value, test for trend = 0.01). Each 0.1 micromol/L increase in plasma selenium levels was related to a 5% (95% CI = 0%-9%) decreased risk of mortality. Plasma selenium levels were not associated with time to progression to CD4 cell count < 200 cells/mm(3) but were weakly and positively related to CD4 cell count in the first years of follow up. Selenium status may be important for clinical outcomes related to HIV disease in sub-Saharan Africa.
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Affiliation(s)
- Roland Kupka
- Department of Nutrition, Harvard School of Public Health, Boston MA, USA.
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23
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Wessner B, Strasser EM, Spittler A, Roth E. Effect of single and combined supply of glutamine, glycine, N-acetylcysteine, and R,S-α-lipoic acid on glutathione content of myelomonocytic cells. Clin Nutr 2003; 22:515-22. [PMID: 14613752 DOI: 10.1016/s0261-5614(03)00053-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
BACKGROUND & AIMS Several diseases are characterised by decreased glutathione (GSH) levels due to an enhanced formation of oxygen radicals. To increase GSH levels, the additional supply of GSH precursors was suggested. In this study we evaluated the potency of a single and combined administration of the GSH modulating substances glutamine (GLN), N-acetylcysteine (NAC), and glycine (GLY) as well as R,S-alpha-lipoic acid (LA) to enhance intracellular GSH content in a well-defined model system. RESULTS Exposure of myelomonocytic U937 cells for 24 h to GLN revealed a 1.5-fold enhancement of GSH levels with a concomitant decrease in the formation of reactive oxygen species and lipid peroxidation. Addition of NAC stimulated GSH formation only at subphysiological GLN levels. GLY enhanced GSH levels under GLN starvation, but caused a diminution of GSH content under optimal GLN supply. LA in combination with 2 mmol/l GLN evoked a 3.6-fold enhancement of GSH content compared to GLN starved cells. CONCLUSION These results demonstrate that the GSH content of U937 cells is dependent on the supply of GLN, NAC, LA, and GLY. Combinations of the single substances can enhance but also decrease the intracellular GSH content, which is of clinical importance when supplying GSH-modulating substances to patients.
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Affiliation(s)
- B Wessner
- Department of Surgery, Research Laboratories, University of Vienna, Austria
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24
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Giordani L, Quaranta MG, Malorni W, Boccanera M, Giacomini E, Viora M. N-acetylcysteine inhibits the induction of an antigen-specific antibody response down-regulating CD40 and CD27 co-stimulatory molecules. Clin Exp Immunol 2002; 129:254-64. [PMID: 12165081 PMCID: PMC1906440 DOI: 10.1046/j.1365-2249.2002.01897.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We investigated the effect of N-acetylcysteine (NAC) on normal human B cell functions. We found that NAC significantly inhibited both the induction of the specific antibody response to the T-dependent antigen Candida albicans and T-dependent pokeweed mitogen (PWM)-induced polyclonal Ig production. NAC did not induce either cell death due to a non-specific toxicity or apoptosis. The NAC-induced inhibitory effect might be a functional consequence of: (i) a down-regulation of the expression on the B cell surface of CD40 and CD27 co-stimulatory molecules and (ii) a down-regulation of interleukin (IL-4) production. In contrast, NAC up-regulated interferon-gamma (IFN-gamma) production. NAC did not induce any effect on the T cell-independent B cell polyclonal activation system. These results indicate that NAC down-regulates T dependent B cell activation and leads to T helper cell type 1 (Th1) polarization.
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Affiliation(s)
- L Giordani
- Department of Immunology, Istituto Superiore di Sanità, Rome, Italy
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25
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Abstract
A growing body of evidence indicates that glutathione (GSH) plays a vitally important role in cellular function. It detoxifies toxic metabolites of drugs and reactive oxygen species and regulates gene expression, apoptosis, and transmembrane transport of organic solutes. The maintenance of GSH homeostasis is essential for the organism to perform its many functions. The turnover of GSH is a dynamic process, and large quantities of GSH are synthesized per day from its precursor amino acids cysteine, glutamic acid, and glycine. Toxic doses of paracetamol deplete intracellular GSH and result in cell death by a combination of mechanisms, leading to necrosis and apoptosis, mainly in the liver. In clinical situations characterized by low GSH, the risk of toxicity from therapeutic doses of paracetamol may conceivably be increased. This toxicity has been reported in chronic alcoholics who have low intrahepatic GSH and who may have an induced enzyme system that generates the toxic metabolite of paracetamol. Considering the large number of alcoholics in our population and the widespread use of paracetamol, this must be a rare and essentially unpredictable occurrence. Except for anecdotal reports, there is no convincing evidence that other populations in which low GSH has been observed-such as patients with human immunodeficiency virus (HIV) infection or chronic hepatitis C, malnourished patients, and patients with cirrhosis-are at higher risk of experiencing adverse events from paracetamol.
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26
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Spada C, Treitinger A, Reis M, Masokawa IY, Verdi JC, Luiz MC, Silveira MVS, Michelon CM, Avila-Junior S, Gil LDO, Ostrowskyl S. The effect of N-acetylcysteine supplementation upon viral load, CD4, CD8, total lymphocyte count and hematocrit in individuals undergoing antiretroviral treatment. Clin Chem Lab Med 2002; 40:452-5. [PMID: 12113286 DOI: 10.1515/cclm.2002.077] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Individuals infected with the human immunodeficiency virus (HIV-1) present with decreased CD4, a progressive increase in viral load, compromised cell immune defense, and hematologic alterations. The aim of this study was to assess the serum viral load, CD4, CD8, lymphocyte count and hematocrit at the beginning of antiretroviral therapy in individuals who were supplemented with N-acetylcysteine (NAC). Twenty volunteers participated in this double-blind, placebo-controlled 180-day study. Ten participants received 600 mg of NAC per day (NAC group) and the other ten serving as a control group received placebo. The above mentioned parameters were determined before treatment, and after 60, 120 and 180 days. In NAC-treated patients hematocrit remained stable and an increase in CD4 cell count took place earlier than that in the control group.
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Affiliation(s)
- Celso Spada
- UFSC Clinical Analysis Department, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, Brazil.
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27
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Viora M, Quaranta MG, Straface E, Vari R, Masella R, Malorni W. Redox imbalance and immune functions: opposite effects of oxidized low-density lipoproteins and N-acetylcysteine. Immunology 2001; 104:431-8. [PMID: 11899429 PMCID: PMC1783329 DOI: 10.1046/j.1365-2567.2001.01334.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
This study investigates the in vitro effects of oxidized low-density lipoproteins (ox-LDL), 'physiological' pro-oxidants, N-acetylcysteine (NAC), a free radical scavenger and glutathione precursor, and their combination on human peripheral blood mononuclear cell functions. We found that treatment with ox-LDL induced a significant down-regulation of proliferative response to mitogens, antigens and interleukin-2. Lipid extracts from ox-LDL were able to reproduce the same effect as the lipoprotein. On the other hand, NAC exposure induced a significant up-regulation of proliferative responses to all the stimuli used. Moreover, we showed that natural killer (NK) cell-mediated cytotoxic activity was significantly down-regulated by ox-LDL while treatment with NAC induced a significant up-regulation of NK-cell activity. Finally, we found that ox-LDL and NAC exerted opposite effects on the cytokine network, interfering both at the protein secretion level and the messenger RNA synthesis level. More importantly, when NAC was used in combination with ox-LDL the proliferative responses, NK-cell-mediated cytotoxic activity and cytokine production were restored to values comparable to controls. These data indicate that ox-LDL and NAC modulate immune functions, exerting opposite effects reflecting their pro-oxidant and antioxidant behaviours. Our results add new insights to the key role played by redox imbalance as a modulator of immune system homeostasis and suggest that an antioxidant drug such as NAC could be useful against pathologies associated with an increase in lipid peroxidation.
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Affiliation(s)
- M Viora
- Immunology Department, Istituto Superiore di Sanità, Rome, Italy.
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28
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Selenium Deficiency Is Associated With Shedding of HIV-1–Infected Cells in the Female Genital Tract. J Acquir Immune Defic Syndr 2001. [DOI: 10.1097/00042560-200104010-00013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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29
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Baeten JM, Mostad SB, Hughes MP, Overbaugh J, Bankson DD, Mandaliya K, Ndinya-Achola JO, Bwayo JJ, Kreiss JK. Selenium deficiency is associated with shedding of HIV-1--infected cells in the female genital tract. J Acquir Immune Defic Syndr 2001; 26:360-4. [PMID: 11317079 DOI: 10.1097/00126334-200104010-00013] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To assess the relation between selenium deficiency and vaginal or cervical shedding of HIV-1-infected cells. DESIGN Cross-sectional study of 318 HIV-1 seropositive women in Mombasa, Kenya. METHODS Vaginal and cervical swab specimens were tested for the presence of HIV-1 DNA by polymerase chain reaction. Multivariate logistic regression models, adjusting for CD4 count and vitamin A deficiency, were used. RESULTS Selenium deficiency (defined as levels <85 microg/L) was observed in 11% of the study population. In unstratified multivariate analyses, there was no significant association between selenium deficiency and vaginal or cervical shedding. In stratified analyses, however, significant associations became apparent after excluding women with predictors of shedding with strong local effects on the genital tract mucosa. Among women who did not use oral contraceptives and who did not have vaginal candidiasis, selenium deficiency was significantly associated with vaginal shedding (adjusted odds ratio [AOR] 2.9, 95% confidence interval [CI] 1.0--8.8, p =.05). Effect modification was also observed in the relation between selenium deficiency and cervical shedding, with a significant association seen among those women who were not using oral contraceptive pills or depot medroxyprogesterone acetate and who did not have Neisseria gonorrhoeae infection (AOR 2.8, 95% CI 1.1--7.0, p =.02). CONCLUSIONS We found selenium deficiency to be associated with a nearly threefold higher likelihood of genital mucosal shedding of HIV-1--infected cells, suggesting that deficiency may increase the infectiousness of women with HIV-1. Nutritional interventions to prevent HIV-1 transmission warrant investigation.
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Affiliation(s)
- J M Baeten
- Department of Epidemiology, University of Washington, Seattle, 98104-2499, USA.
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30
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Rabson AB, Lin HC. NF-kappa B and HIV: linking viral and immune activation. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2001; 48:161-207. [PMID: 10987091 DOI: 10.1016/s1054-3589(00)48006-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- A B Rabson
- Department of Molecular Genetics and Microbiology, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway 08854, USA
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31
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Micke P, Beeh KM, Schlaak JF, Buhl R. Oral supplementation with whey proteins increases plasma glutathione levels of HIV-infected patients. Eur J Clin Invest 2001; 31:171-8. [PMID: 11168457 DOI: 10.1046/j.1365-2362.2001.00781.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
HIV infection is characterized by an enhanced oxidant burden and a systemic deficiency of the tripeptide glutathione (GSH), a major antioxidant. The semi-essential amino acid cysteine is the main source of the free sulfhydryl group of GSH and limits its synthesis. Therefore, different strategies to supplement cysteine supply have been suggested to increase glutathione levels in HIV-infected individuals. The aim of this study was to evaluate the effect of oral supplementation with two different cysteine-rich whey protein formulas on plasma GSH levels and parameters of oxidative stress and immune status in HIV-infected patients. In a prospective double blind clinical trial, 30 patients (25 male, 5 female; mean age (+/- SD) 42 +/- 9.8 years) with stable HIV infection (221 +/- 102 CD4 + lymphocytes L-1) were randomized to a supplemental diet with a daily dose of 45 g whey proteins of either Protectamin (Fresenius Kabi, Bad Hamburg, Germany) or Immunocal (Immunotec, Vandreuil, Canada) for two weeks. Plasma concentrations of total, reduced and oxidized GSH, superoxide anion (O2-) release by blood mononuclear cells, plasma levels of TNF-alpha and interleukins 2 and 12 were quantified with standard methods at baseline and after therapy. Pre-therapy, plasma GSH levels (Protectamin: 1.92 +/- 0.6 microM; Immunocal: 1.98 +/- 0.9 microM) were less than normal (2.64 +/- 0.7 microM, P = 0.03). Following two weeks of oral supplementation with whey proteins, plasma GSH levels increased in the Protectamin group by 44 +/- 56% (2.79 +/- 1.2 microM, P = 0.004) while the difference in the Immunocal group did not reach significance (+ 24.5 +/- 59%, 2.51 +/- 1.48 microM, P = 0.43). Spontaneous O2- release by blood mononuclear cells was stable (20.1 +/- 14.2 vs. 22.6 +/- 16.1 nmol h-1 10-6 cells, P = 0.52) whereas PMA-induced O2- release decreased in the Protectamin group (53.7 +/- 19 vs. 39.8 +/- 18 nmol h-1 10-6 cells, P = 0.04). Plasma concentrations of TNF-alpha and interleukins 2 and 12 (P > 0.08, all comparisons) as well as routine clinical parameters remained unchanged. Therapy was well tolerated. In glutathione-deficient patients with advanced HIV-infection, short-term oral supplementation with whey proteins increases plasma glutathione levels. A long-term clinical trial is clearly warranted to see if this "biochemical efficacy" of whey proteins translates into a more favourable course of the disease.
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Affiliation(s)
- P Micke
- Pulmonary Division, III. Medical Department, Mainz University Hospital, D-455101 Mainz, Germany.
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Abstract
The interaction of superoxide radicals with N-acetylcysteine (RSH) in an aqueous solution of pH 7 using the technique of steady state radiolysis has been investigated in this paper. The radiolytic yield of the products (G value) of RSH consumption and disulfide of N-acetylcysteine (RSSR) formation has been determined. The G value of the products is not dependent on the concentration of RSH (at the plateau of dilution curve) or on the inverse of the square root of the dose rate (dose rate)(-1/2), from which it is concluded that in this reaction there is no character of chain reaction. The disulfide of N-acetylcysteine is the only sulfur final product. Hydrogen peroxide is not a reaction product, and accordingly the reaction of O(2)(*-) with RSH does not proceed via hydrogen atom abstraction from RSH. A reaction mechanism is proposed, and an overall rate constant of 68 M(-1) s(-1) has been estimated.
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Affiliation(s)
- M Benrahmoune
- Laboratoire de Chimie-Physique, Université Paris V, Paris, France
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De Rosa SC, Zaretsky MD, Dubs JG, Roederer M, Anderson M, Green A, Mitra D, Watanabe N, Nakamura H, Tjioe I, Deresinski SC, Moore WA, Ela SW, Parks D, Herzenberg LA, Herzenberg LA. N-acetylcysteine replenishes glutathione in HIV infection. Eur J Clin Invest 2000; 30:915-29. [PMID: 11029607 DOI: 10.1046/j.1365-2362.2000.00736.x] [Citation(s) in RCA: 187] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Glutathione (GSH) deficiency is common in HIV-infected individuals and is associated with impaired T cell function and impaired survival. N-acetylcysteine (NAC) is used to replenish GSH that has been depleted by acetaminophen overdose. Studies here test oral administration of NAC for safe and effective GSH replenishment in HIV infection. DESIGN Oral NAC administration in a randomized, 8-week double-blind, placebo-controlled trial followed by optional open-label drug for up to 24 weeks. SUBJECTS HIV-infected, low GSH, CD4 T cells < 500 micro L(-1), no active opportunistic infections or other debilitation; n = 81. Study conducted prior to introduction of protease inhibitors. RESULTS Whole blood GSH levels in NAC arm subjects significantly increased from 0.88 mM to 0.98 mM, bringing GSH levels in NAC-treated subjects to 89% of uninfected controls (P = 0.03). Baseline GSH levels in the placebo group (0.91) remained essentially the same during the 8 week placebo-controlled trial. T cell GSH, adjusted for CD4 T cell count and beta2-microglobulin levels, also increased in the NAC-treated subjects (P = 0.04). Adverse effects were minimal and not significantly associated with NAC ingestion. CONCLUSION NAC treatment for 8 weeks safely replenishes whole blood GSH and T cell GSH in HIV-infected individuals. Thus, NAC offers useful adjunct therapy to increase protection against oxidative stress, improve immune system function and increase detoxification of acetaminophen and other drugs. These findings suggest that NAC therapy could be valuable in other clinical situations in which GSH deficiency or oxidative stress plays a role in disease pathology, e.g. rheumatoid arthritis, Parkinson's disease, hepatitis, liver cirrhosis, septic shock and diabetes.
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Affiliation(s)
- S C De Rosa
- Department of Genetics, Stanford University, USA
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Müller F, Svardal AM, Nordoy I, Berge RK, Aukrust P, Frøland SS. Virological and immunological effects of antioxidant treatment in patients with HIV infection. Eur J Clin Invest 2000; 30:905-14. [PMID: 11029606 DOI: 10.1046/j.1365-2362.2000.00727.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Intracellular oxidative stress in CD4+ lymphocytes due to disturbed glutathione homeostasis may lead to impaired lymphocyte functions and enhanced HIV replication in patients with HIV infection, especially in those with advanced immunodeficiency. The aim of the present study was to assess whether short-term, high-dose antioxidant treatment might have effects on immunological and virological parameters in patients with HIV infection. MATERIALS AND METHODS In this pilot study, we examined virological and immunological effects of antioxidant combination treatment for 6 days with high doses of N-acetylcysteine (NAC) and vitamin C in 8 patients with HIV infection. The following were assayed before, during and after antioxidant treatment: HIV RNA plasma levels; numbers of CD4+, CD8+, and CD14+ leukocytes in blood; plasma thiols; intracellular glutathione redox status in CD4+ lymphocytes and CD14+ monocytes; lymphocyte proliferation; lymphocyte apoptosis and plasma levels of tumour necrosis factor (TNF)alpha; soluble TNF receptors and neopterin in plasma. RESULTS No significant changes in HIV RNA plasma levels or CD4+ lymphocyte counts in blood were noted during antioxidant treatment in the patient group. However, in the 5 patients with the most advanced immunodeficiency (CD4+ lymphocyte counts < 200 x 106 L(-1)), a significant rise in CD4+ lymphocyte count, a reduction in HIV RNA plasma level of 0.8 log, an enhanced lymphocyte proliferation and an increased level of intracellular glutathione in CD4+ lymphocytes were found. No change in lymphocyte apoptosis was noted. CONCLUSIONS Short-term, high-dose combination treatment with NAC and vitamin C in patients with HIV infection and advanced immunodeficiency lead to immunological and virological effects that might be of therapeutic value.
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Affiliation(s)
- F Müller
- University of Oslo, The National Hospital, Rikshospitalet, Oslo, Norway.
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Affiliation(s)
- F Staal
- Erasmus University Rotterdam, Rotterdam, The Netherlands.
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Are shorter courses of N-acetylcysteine for acetaminophen poisoning efficacious? A review of the literature. CLINICAL PEDIATRIC EMERGENCY MEDICINE 2000. [DOI: 10.1016/s1522-8401(00)90032-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Affiliation(s)
- O A Levander
- Beltsville Human Nutrition Research Center, U. S. Department of Agriculture, Maryland 20705, USA
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Perl A, Banki K. Genetic and metabolic control of the mitochondrial transmembrane potential and reactive oxygen intermediate production in HIV disease. Antioxid Redox Signal 2000; 2:551-73. [PMID: 11229368 DOI: 10.1089/15230860050192323] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Redox mechanims play important roles in replication of human immunodeficiency virus type 1 (HIV-1) and cellular susceptibility to apoptosis signals. Viral replication and accelerated turnover of CD4+ T cells occur throughout a prolonged asymptomatic phase in patients infected by HIV-1. Disease development is associated with steady loss of CD4+ T cells by apoptosis, increased rate of opportunistic infections and lymphoproliferative diseases, disruption of energy metabolism, and generalized wasting. Such pathological states are preceded by: (i) depletion of intracellular antioxidants, glutathione (GSH) and thioredoxin (TRX), (ii) increased reactive oxygen species (ROS) production, and (iii) changes in mitochondrial transmembrane potential (deltapsi(m)). Disruption of deltapsi(m) appears to be the point of no return in the effector phase of apoptosis. Viral proteins Tat, Nef, Vpr, protease, and gp120, have been implicated in initiation and/or intensification of oxidative stress and disruption of deltapsi(m). Redox-sensitive transcription factors, NF-kappaB, AP-1, and p53, support expression of viral genes and proinflammatory lymphokines. ROS regulate apoptosis signaling through Fas, tumor necrosis factor (TNF), and related cell death receptors, as well as the T-cell receptor. Oxidative stress in HIV-infected donors is accompanied by increased glucose utilization both on the cellular and organismal levels. Generation of GSH and TRX from their corresponding oxidized forms is dependent on NADPH provided through the pentose phosphate pathway of glucose metabolism. This article seeks to delineate the genetic and metabolic bases of HIV-induced oxidative stress. Such understanding should lead to development of effective antioxidant therapies in HIV disease.
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Affiliation(s)
- A Perl
- Department of Medicine, State University of New York Health Science Center, College of Medicine, Syracuse 13210, USA.
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Abstract
Randomly selected asymptomatic HIV-positive persons reveal, on average, a massive daily loss of sulphur, which appears to represent in first approximation the mean loss throughout the asymptomatic stage, and may explain the widely observed decrease in cyst(e)ine and glutathione levels. This sulphur loss is reasonably expected to lead, within a few years, to a life-threatening condition and may, therefore, contribute decisively to disease progression. Importantly, the rate of sulphur loss is not ameliorated by highly active antiretroviral therapy and may contribute to antiretroviral treatment failure. Several clinical trials on N-acetyl-cysteine treatment of HIV-positive patients have revealed various therapeutic effects, but did not meet the rigorous standards for approval by the health authorities.
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Affiliation(s)
- W Dröge
- Division of Immunochemistry, Deutsches Krebforschungszentrum, Heidelberg, Germany.
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Abstract
The family of glutathione peroxidases comprises four distinct mammalian selenoproteins. The classical enzyme (cGPx) is ubiquitously distributed. According to animal, cell culture and inverse genetic studies, its primary function is to counteract oxidative attack. It is dispensible in unstressed animals, and accordingly ranks low in the hierarchy of glutathione peroxidases. The gastrointestinal isoenzyme (GI-GPx) is most related to cGPx and is exclusively expressed in the gastrointestinal tract. It might provide a barrier against hydroperoxides derived from the diet or from metabolism of ingested xenobiotics. The extreme stability in selenium deficiency ranks this glutathione peroxidase highest in the hierarchy of selenoproteins and points to a more vital function than that of cGPx. Plasma GPx (pGPx) behaves similar to cGPx in selenium deficiency. It is directed to extracellular compartments and is expressed in various tissues in contact with body fluids, e.g., kidney, ciliary body, and maternal/fetal interfaces. It has to be rated as an efficient extracellular antioxidant device, though with low capacity because of the limited extracellular content of potential thiol substrates. Phospholipid hydroperoxide glutathione peroxidase (PHGPx), originally presumed to be a universal antioxidant enzyme protecting membrane lipids, appears to have adopted a variety of specific roles like silencing lipoxygenases and becoming an enzymatically inactive structural component of the mitochondrial capsule during sperm maturation. Thus, all individual isoenzymes are efficient peroxidases in principle, but beyond their mere antioxidant potential may exert cell- and tissue-specific roles in metabolic regulation, as is evident for PHGPx and may be expected for others.
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