Antioxidants and progression of human immunodeficiency virus (HIV) disease

Role of food nutrients and supplementation in fighting against viral infections and boosting immunity: A review

BACKGROUND

The viral infections can be highly contagious and easily transmissible, which even can lead to a pandemic, like the recent COVID-19 outbreak, causing massive deaths worldwide. While, still the best practical way to prevent the transmission of viruses is to practice self-sanitation and follow social distancing principles, enhancing the individual's immunity through the consumption of proper foods containing balanced nutrients can have significant result against viral infections. Foods containing nutrients such as vitamins, minerals, fatty acids, few polysaccharides, and some non-nutrients (i.e. polyphenols) have shown therapeutic potential against the function of viruses and can increase the immunity of people.

SCOPE AND APPROACH

The results of conducted works aiming for studying the potential antiviral characteristics of diverse groups of foods and food's nutrients (in terms of polysaccharides, proteins, lipids, vitamins, and minerals) are critically discussed.

KEY FINDINGS AND CONCLUSION

Nutrients, besides playing an important role in maintaining normal physiology of human's body and healthiness, are also required for enhancing the immunity of the body and can be effective against viral infections. They can present antiviral capacity either by entering into the defensive mechanism directly through interfering with the target viruses, or indirectly through activating the cells associated with the adaptive immune system. During the current situation of COVID-19 pandemic (the lack of proper curative viral drug), enhancing the immunity of individual's body through proposing the appropriate diet (rich in both macro and micro-nutrients) is one of few practical preventive measures available in fighting against Coronaviruses, this significant health-threatening virus, as well as other viruses in general.

Dawn of antioxidants and immune modulators to stop HIV-progression and boost the immune system in HIV/AIDS patients: An updated comprehensive and critical review

In the last two decades, human immunodeficiency virus (HIV), the retrovirus responsible for the acquired immunodeficiency syndrome (AIDS), is one of the leading causes of morbidity and mortality, worldwide. Providing the optimum management of HIV/AIDS is a major challenge in the 21st century. Since, HIV-infected persons have an extended lifespan due to the development of effective antiretroviral therapies, malnutrition is becoming central factors of long-term survivors. The nutrition status of AIDS patients has a significant influence on the maintenance and optimal effectiveness of the immune system. Micronutrient therapy in combination with allopathic treatments can extend and improve the quality and quantity of life in individuals infected with HIV/AIDS. HIV infection is thought to lead to augmented oxidative stress which may in turn lead to faster development of HIV disease. Hence, antioxidants might have a significant role in the treatment of HIV/AIDS. An additional approach to treating HIV infection is fortifying the immune response of infected people. Immune modulators help to activate and boost the normal immune function. The present review first describes the boon of antioxidants (especially Vitamin A) and immune modulators (cytolin, resveratrol, murabutide, setarud, tucaresol, AVR118, Immunitin (HE2000), reticulose, and interleukin-7) in the treatment of HIV/AIDS. Then, providing a comparatively succinct outline on updated patents study on antioxidants and immune modulators to treat HIV/AIDS will be discussed.

The putative herpes simplex virus 1 chaperone protein UL32 modulates disulfide bond formation during infection

During DNA encapsidation, herpes simplex virus 1 (HSV-1) procapsids are converted to DNA-containing capsids by a process involving activation of the viral protease, expulsion of the scaffold proteins, and the uptake of viral DNA. Encapsidation requires six minor capsid proteins (UL6, UL15, UL17, UL25, UL28, and UL33) and one viral protein, UL32, not found to be associated with capsids. Although functions have been assigned to each of the minor capsid proteins, the role of UL32 in encapsidation has remained a mystery. Using an HSV-1 variant containing a functional hemagglutinin-tagged UL32, we demonstrated that UL32 was synthesized with true late kinetics and that it exhibited a previously unrecognized localization pattern. At 6 to 9 h postinfection (hpi), UL32 accumulated in viral replication compartments in the nucleus of the host cell, while at 24 hpi, it was additionally found in the cytoplasm. A newly generated UL32-null mutant was used to confirm that although B capsids containing wild-type levels of capsid proteins were synthesized, these procapsids were unable to initiate the encapsidation process. Furthermore, we showed that UL32 is redox sensitive and identified two highly conserved oxidoreductase-like C-X-X-C motifs that are essential for protein function. In addition, the disulfide bond profiles of the viral proteins UL6, UL25, and VP19C and the viral protease, VP24, were altered in the absence of UL32, suggesting that UL32 may act to modulate disulfide bond formation during procapsid assembly and maturation.

IMPORTANCE

Although functions have been assigned to six of the seven required packaging proteins of HSV, the role of UL32 in encapsidation has remained a mystery. UL32 is a cysteine-rich viral protein that contains C-X-X-C motifs reminiscent of those in proteins that participate in the regulation of disulfide bond formation. We have previously demonstrated that disulfide bonds are required for the formation and stability of the viral capsids and are also important for the formation and stability of the UL6 portal ring. In this report, we demonstrate that the disulfide bond profiles of the viral proteins UL6, UL25, and VP19C and the viral protease, VP24, are altered in cells infected with a newly isolated UL32-null mutant virus, suggesting that UL32 acts as a chaperone capable of modulating disulfide bond formation. Furthermore, these results suggest that proper regulation of disulfide bonds is essential for initiating encapsidation.

Inhibition of rotavirus ECwt infection in ICR suckling mice by N-acetylcysteine, peroxisome proliferator-activated receptor gamma agonists and cyclooxygenase-2 inhibitors

Live attenuated vaccines have recently been introduced for preventing rotavirus disease in children. However, alternative strategies for prevention and treatment of rotavirus infection are needed mainly in developing countries where low vaccine coverage occurs. In the present work, N-acetylcysteine (NAC), ascorbic acid (AA), some nonsteroidal anti-inflammatory drugs (NSAIDs) and peroxisome proliferator-activated receptor gamma (PPARγ) agonists were tested for their ability to interfere with rotavirus ECwt infectivity as detected by the percentage of viral antigen-positive cells of small intestinal villi isolated from ECwt-infected ICR mice. Administration of 6 mg NAC/kg every 8 h for three days following the first diarrhoeal episode reduced viral infectivity by about 90%. Administration of AA, ibuprofen, diclofenac, pioglitazone or rosiglitazone decreased viral infectivity by about 55%, 90%, 35%, 32% and 25%, respectively. ECwt infection of mice increased expression of cyclooxygenase-2, ERp57, Hsc70, NF-κB, Hsp70, protein disulphide isomerase (PDI) and PPARγ in intestinal villus cells. NAC treatment of ECwt-infected mice reduced Hsc70 and PDI expression to levels similar to those observed in villi from uninfected control mice. The present results suggest that the drugs tested in the present work could be assayed in preventing or treating rotaviral diarrhoea in children and young animals.

N-Acetylcysteine treatment of rotavirus-associated diarrhea in children

Rotaviruses are the leading cause of severe, acute, and dehydrating diarrhea affecting children under 5 years of age worldwide. Despite an important reduction in rotavirus-caused deaths as a consequence of the rotavirus vaccine, alternative or complementary strategies for preventing or treating rotavirus-associated diarrhea are needed mainly in the poorest countries. We describe the cases of four rotavirus-unvaccinated 12-13-month-old girls and a 5-year-old boy who developed rotavirus-associated diarrhea confirmed by enzyme-linked immunosorbent assay, Western blotting, and immunochemistry analyses. After the first day of diarrheal episodes, three of the five patients were immediately administered oral N-acetylcysteine (NAC) 60 mg/kg daily, divided into three equal doses every 8 hours. The other two patients did not receive NAC and served as controls. Administration of NAC resulted in a decreased number of diarrheal episodes, excretion of fecal rotavirus antigen, and resolution of symptoms after 2 days of treatment. Our results suggest that NAC treatment after the first diarrheal episode could be an efficient strategy for treating rotavirus-affected children and preventing the associated severe life-threatening accompanying dehydration.

Inhibitory effects of glutathione on dengue virus production

Reduced glutathione (GSH) is the most powerful intracellular antioxidant and also involved in viral infections. The pathogenesis of dengue virus (DV) infection has not been completely clarified. This study investigated the relationship between DV serotype 2 (DV2) infections and host intracellular GSH content. Results showed infection with DV2 resulted in a decrease in intracellular GSH, which caused NF-kappaB activation and increased DV2 production. Supplemental GSH significantly inhibited activation of NF-kappaB, resulting in a decreased production of DV2 in HepG2 cells. Furthermore, high activity of NF-kappaB and increased production of DV2 was observed in HepG2 cells treated with buthionine sulfoximine (BSO), an inhibitor of GSH synthesis. In conclusion, DV2 infection could reduce host intracellular GSH concentration and benefited from this process. Supplemental GSH could inhibit viral production, indicating GSH might be valuable in the prevention and treatment of DV2 infection.

Reconciling conflicting clinical studies of antioxidant supplementation as HIV therapy: a mathematical approach

BACKGROUND

Small, highly reactive molecules called reactive oxygen species (ROS) play a crucial role in cell signalling and infection control. However, high levels of ROS can cause significant damage to cell structure and function. Studies have shown that infection with the human immunodeficiency virus (HIV) results in increased ROS concentrations, which can in turn lead to faster progression of HIV infection, and cause CD4+ T-cell apoptosis. To counteract these effects, clinical studies have explored the possibility of raising antioxidant levels, with mixed results.

METHODS

In this paper, a mathematical model is used to explore this potential therapy, both analytically and numerically. For the numerical work, we use clinical data from both HIV-negative and HIV-positive injection drug users (IDUs) to estimate model parameters; these groups have lower baseline concentrations of antioxidants than non-IDU controls.

RESULTS

Our model suggests that increases in CD4+ T cell concentrations can result from moderate levels of daily antioxidant supplementation, while excessive supplementation has the potential to cause periods of immunosuppression.

CONCLUSION

We discuss implications for HIV therapy in IDUs and other populations which may have low baseline concentrations of antioxidants.

Potential of NIR-FT-Raman spectroscopy in natural carotenoid analysis

This paper demonstrates the special advantages of FT-Raman spectroscopy for in situ studies of several carotenoids that occur ubiquitously in the plant kingdom. Spectra obtained from various tissues of a range of plant species indicate that the wavenumber location of C=C stretching vibrations is mainly influenced both by the length as well as by the terminal substituents of the polyene chain of carotenoids and by their interaction with other plant constituents. The obtained results show also the usefulness of Raman spectroscopy in the investigation of cis-trans isomerization of carotenoids during processing. Additionally, 2-D Raman mappings present a unique possibility to evaluate the individual distribution of carotenoids in the intact plant tissue; in this context different 7-, 8-, and 9-double bond conjugated carotenoids can be analyzed independently in the same sample. Furthermore, the use of Raman spectroscopy for in situ detection of unstable substances such as epoxycarotenoids is discussed.

Iron and infection: effects of host iron status and the iron-regulatory genes haptoglobin and NRAMP1 (SLC11A1) on host-pathogen interactions in tuberculosis and HIV

There are many lines of evidence illustrating that iron plays a pivotal role in modulating the battle for survival between mammalian hosts and their pathogens. Each displays considerable genetic investment in a wide range of mechanisms for acquiring and maintaining iron. These competitive mechanisms are highly complex, existing within an interacting matrix of absorption, transport, storage and detoxification systems, each of which are iron-responsive and thus able to adapt to the different phases of infection. Considerable genetic polymorphism in some of these systems, with signals of geographic selection in the hosts, and niche selection in the pathogens, indicates that they are critical for species survival. In this review we briefly summarize the role of iron in host immune function before reviewing the available evidence that iron modulates susceptibility and disease outcomes in HIV and TB (tuberculosis). We then examine the putative role of iron-related host genes by focussing on two candidate genes, haptoglobin and NRAMP1, for which there are common polymorphic variants in humans with strong evidence of functionally distinct biochemical phenotypes that would be predicted to influence the course of HIV and TB infections. Finally, we examine the limited evidence so far available that nutrient-gene interactions are likely to influence the way in which gene variants can protect against infection. We conclude that there is a wealth of evidence associating alterations in iron balance and in iron-regulatory systems with disease progression, but that many issues related to the direction of causality, mechanisms of action and sensitivity to pharmacological intervention remain to be elucidated. Since iron is probably the most widely prescribed compound throughout the world, used in both preventative and treatment regimens, a deeper understanding of the host-pathogen interactions relating to iron constitutes an important area for both basic and clinical research.

Malondialdehyde production in Jurkat T cells subjected to oxidative stress

OBJECTIVE

We investigated the relation between membrane lipid peroxidation, as evaluated by malondialdehyde (MDA), and oxidative stimuli in the Jurkat T-cell line and designed a cellular model to assess the antioxidant potential of compounds.

METHODS

Jurkat T cells were subjected to different concentrations of Fe(2+) ions (from 25 to 150 micromol/L) or H(2)O(2) (from 0.1 to 5 mmol/L), and MDA was determined after separation in high-performance liquid chromatography of the adduct with thiobarbituric acid. MDA production also was investigated in cells supplemented with epigallocatechin gallate and genistein and subjected to Fe(2+) oxidative treatment.

RESULTS

MDA production increased with the concentration of Fe(2+), whereas H(2)O(2) had no effect at any concentration. Oxidative stress for 15 min or 2 h produced similar MDA levels. The supplementation of epigallocatechin gallate partly prevented MDA production (about 40%, P < 0.05), whereas genistein exerted no preventive effect on lipid peroxidation.

CONCLUSION

We propose this cellular model, consisting of Jurkat T cells subjected to 100 micromol/L of Fe(2+) for 15 min, to study the protective effect of antioxidant supplementation against membrane lipid peroxidation.

Tomato intake in relation to mortality and morbidity among Sudanese children

The intake of foods that contain high levels of antioxidants may counteract the adverse effects of oxidative stress and lead to improved immune function and reduced risk of infectious disease. We prospectively examined the relationship between the consumption of tomatoes, a rich source of antioxidants, and mortality and diarrheal and respiratory morbidity rates among 28,753 children who were 6-60 mo old and enrolled in a longitudinal study in the Sudan. Children in each household were visited every 6 mo for a maximum of four visits. At each round, mothers recalled whether a child had consumed tomatoes in the previous 24 h. Events (death or morbidity) reported at each round were prospectively allocated according to the number of days of tomato intake. Intake of tomatoes for 2 or 3 d compared with none was associated, respectively, with 48% (relative risk, 0. 53; 95% confidence interval, 0.30-0.91) and 83% (0.17; 0.04-0.72) reductions in morality rates (P: for trend = 0.002). The association between tomato use and death remained statistically significant (P: for trend = 0.004), even after further adjustment for total vitamin A intake. Tomato intake was also associated with a reduced risk of death associated with diarrhea in the week preceding death (P: for trend = 0.009) or fever (P: for trend = 0.04). Intake of tomatoes was also inversely and significantly associated with the risks of diarrheal and respiratory infections. Our data suggest that tomatoes may be beneficial for child health but also emphasize the general importance of food-based approaches to the prevention of micronutrient malnutrition and protection of the health of children in developing countries.