Article

Micronutrient cooperation in the suppression of HIV production in chronically and latently infected cells

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Abstract

Nutrients are known to display pharmacologic activity against viruses and to exert cooperative effects in cells. To study the influence of nutrient cooperation on HIV production in chronically infected T lymphocytes, we evaluated the individual and combined effects of nutrients on HIV-1 reverse transcriptase (RT) released into the culture supernatant. In unstimulated cells, low concentrations of single nutrients, namely ascorbic acid (AA), green tea polyphenols (GT) or lysine, did not significantly suppress HIV-1 RT production. However, when GT (25 µg/ml) and AA (32-64 µg/ml) were combined and applied to cells, extracellular RT was significantly reduced relative to the control. Combining GT (25 µg/ml) with lysine (25 µg/ml) also reduced the RT level to a greater extent (51% of control) than was observed wih lysine alone, and the addition of AA (16 µg/ml) to the combination further decreased RT to 17% of the control (p=0.06). Under the same assay conditions, the nucleoside analog azidothymidine did not significantly suppress HIV production at low to moderate concentrations (0.5-1.0 µg/ml), but did reduce the RT level to 40% of the control (p=0.02) at the highest dose tested (2 µg/ml). In unstimulated cells as well as in latently infected cells stimulated with mitogen (PMA or TNF-α), a nutrient mixture containing GT, AA and amino acids imparted significantly greater RT suppression than equivalent concentrations of key individual components. Nutrient effects on RT suppression were virus-specific and were not due to non-specific cellular toxicity. These results suggest that relatively non-toxic micronutrient combinations are more potent than single nutrients in suppressing virus production in chronically infected T cells, indicating that the constituent nutrients have a cooperative effect in HIV inhibition.

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... 4. Nutrients can directly suppress viral infections host-cells receptor (Mahmood et al., 1993, Fassina et al., 2002). More recently, green tea extract enriched in such polyphenols (80% by weight) was shown to suppress HIV production in chronically and latently infected cells (Jariwalla et al., 2010).Fig. 5 ...
... Studies conducted by us of micronutrient combinations in laboratory cultures of HIV infected cells have provided further support for nutritional efficacy in viral immunodeficiency disease (Jariwalla et al., 2010). In these studies, we compared the ability of micronutrient combinations to single nutrients in the suppression of HIV replication in both chronically and latently infected cells. ...
... In contrast, exposure of cells to combinations of micronutrients conferred significantly greater HIV suppression compared to single nutrients, indicating a synergistic effect. A nutritional mixture (NM), consisting of vitamin C, green tea extract, amino acids (lysine, proline, arginine), NAC and selenium also gave enhanced suppression of HIV production in this cell line compared to single nutrients (Jariwalla et al., 2010; see alsoTable 2). A similar inhibitory effect on cytokine-stimulated virus expression was obtained in latently infected T cells, indicating that micronutrients cooperate to suppress virus expression in both chronically and latently-stimulated cells (Jariwalla et al., 2010;Table 2). ...
... Based on this study and our earlier findings [18,19,27], this combination of plant-derived compounds and micronutrients may constitute a new anti-SARS-CoV-2 strategy by simultaneously affecting multiple aspects of viral life cycle, including viral entry and replication. This strategy was also implemented in our earlier studies, including those of human influenza H1N1, bird flu H1N5, and others, which were based on selecting natural components that simultaneously affect key pathology mechanisms across a wide spectrum of infective agents [28][29][30][31]. ...
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Despite vaccine availability, the global spread of COVID-19 continues, largely facilitated by emerging SARS-CoV-2 mutations. Our earlier research documented that a specific combination of plant-derived compounds can inhibit SARS-CoV-2 binding to its ACE2 receptor and controlling key cellular mechanisms of viral infectivity. In this study, we evaluated the efficacy of a defined mixture of plant extracts and micronutrients against original SARS-CoV-2 and its Alpha, Beta, Gamma, Delta, Kappa, and Mu variants. The composition containing vitamin C, N-acetylcysteine, resveratrol, theaflavin, curcumin, quercetin, naringenin, baicalin, and broccoli extract demonstrated a highest efficacy by inhibiting the receptor-binding domain (RBD) binding of SARS-CoV-2 to its cellular ACE2 receptor by 90%. In vitro exposure of test pseudo-typed variants to this formula for 1 h before or simultaneously administrated to human pulmonary cells resulted in up to 60% inhibition in their cellular entry. Additionally, this composition significantly inhibited other cellular mechanisms of viral infectivity, including the activity of viral RdRp, furin, and cathepsin L. These findings demonstrate the efficacy of natural compounds against SARS-CoV-2 including its mutated forms through pleiotropic mechanisms. Our results imply that simultaneous inhibition of multiple mechanisms of viral infection of host cells could be an effective strategy to prevent SARS-CoV-2 infection.
... Such a comprehensive effects of naturally occurring compounds on several mechanisms associated with viral infectivity is not surprising. This strategy was also implemented in our earlier studies, including those of human influenza H1N1, bird flu H1N5, and others, which were based on selecting natural components that simultaneously affect key pathology mechanisms across a wide spectrum of infective agents [30]- [33]. ...
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SARS-CoV-2 pandemic remains a challenge to human health and economy worldwide. Previously we have shown that a combination of active plant-derived compounds and plant extracts can dose-dependently inhibit binding of RBD-spike protein SARS-CoV-2 to the ACE2 receptor and its expression on human alveolar epithelial cells. Here we use eGFP-luciferase-SARS-CoV-2 spike protein pseudo-virions and SARS-CoV-2-RdRp, to show if the antiviral effectiveness of this combination of plant-derived compounds and plant extracts expands to other important key mechanisms of SARS-CoV-2 infection. Or results revealed that this combination of five plant-derived compounds inhibited the attachment of the SARS-CoV-2 pseudo-typed particles with lung hACE2/A549 cells. In addition, it down-regulated the activity of key enzymes known to be crucial for the entry of the SARS-CoV-2 virus, such as TMPRSS2, furin and cathepsin L, but not their expression at protein level. This combination did not affect ACE2 binding to and ACE2 enzymatic activity, but modestly decrease cellular expression of neuropilin-1 molecule and significantly inhibited activity of viral RdRp. This study demonstrates inhibitory effects of this combination on key cellular mechanisms of SARS-CoV-2 infection. The findings further support the use of plant-derived compounds as effective health measures against SARS-CoV-2-caused infection.
... [18][19][20] Numerous in vitro, in vivo, and human studies conducted by us and others, involving different viruses, for example, HIV, H1N1, H1N9, and bird flu, confirm the universality of ascorbic acid efficacy in various viral infections and pleiotropic effects achieved from its combination with other natural compounds. [21][22][23] Our findings show that vitamin C has a consistent and significant lowering effect on ACE2 expression exercised at different molecular levels in human alveolar epithelial cells, but also in microvascular endothelial cells-the 2 main cell types affected by the SARS-CoV-2. In microvascular endothelial cells, ascorbic acid could inhibit ACE2 expression at the protein (Western blot) and RNA levels. ...
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... Other studies showed L-cysteine and the tripeptide glutathione inhibit chronic HIV expression [17,18], while N-acetyl L-cysteine and selenium inhibit HIV activation in the latent stage of the infected cells [16,19,20]. Flavonoids including the polyphenol EGCG are found to inhibit HIV at the early stage by blocking interaction of the virus with host cells receptors [21,22], and also at the latent and chronic stages of the infected cells [23]. ...
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The HIV-infected population is known to be oxidatively stressed and deficient in antioxidant micronutrients. Since in vitro replication of HIV is increased with oxidative stress, this study assessed the effect of antioxidant vitamin supplementation on lipid peroxidation, a measure of oxidative stress, and viral load in humans. A randomized placebo-controlled, double-blind study. Forty-nine HIV-positive patients were randomized to receive supplements of both DL-alpha-tocopherol acetate (800 IU daily) and vitamin C (1000 mg daily), or matched placebo, for 3 months. Plasma antioxidant micronutrient status, breath pentane output, plasma lipid peroxides, malondialdehyde and viral load were measured at baseline and at 3 months. New or recurrent infections for the 6-month period after study entry were also recorded. The vitamin group (n = 26) had an increase in plasma concentrations of alpha-tocopherol (P < 0.0005) and vitamin C (P < 0.005) and a reduction in lipid peroxidation measured by breath pentane (P < 0.025), plasma lipid peroxides (P < 0.01) and malondialdehyde (P < 0.0005) when compared with controls (n = 23). There was also a trend towards a reduction in viral load (mean +/- SD changes over 3 months, -0.45 +/- 0.39 versus +0.50 +/- 0.40 log10 copies/ml; P = 0.1; 95% confidence interval, -0.21 to -2.14). The number of infections reported was nine in the vitamin group and seven in the placebo group. Supplements of vitamin E and C reduce oxidative stress in HIV and produce a trend towards a reduction in viral load. This is worthy of larger clinical trials, especially in HIV-infected persons who cannot afford new combination therapies.
Article
The increasing recognition of green tea and tea polyphenols as cancer preventives has created a need for a study of their bioavailability. For this purpose, we synthesized [3H] (-)-epigallocatechin gallate ([3H]EGCG) with a specific activity of 48.1 GBq/mmol and directly administered the solution into the stomachs of CD-1 female or male mice. Radioactivity in the digestive tract, various organs, blood, urine and feces was measured with an oxidizer at various times after administration and significant radioactivity was found in the previously reported target organs of EGCG and green tea extract (digestive tract, liver, lung, pancreas, mammary gland and skin), as well as other organs (brain, kidney, uterus and ovary and testes) in both sexes. Incorporation of radioactivity in the cells was confirmed by microautoradiography. Within 24 h, 6.6 (females) and 6.4% (males) of total administered radioactivity was excreted in the urine and 37.7 and 33.1% in feces. HPLC analysis of urine from both sexes revealed that 0.03-0.59% of administered [3H]EGCG, along with at least five metabolites, was excreted. In addition, we found that a second, equal administration to female mice after a 6 h interval enhanced tissue levels of radioactivity in blood, brain, liver, pancreas, bladder and bone 4-6 times above those after a single administration. These results suggest that frequent consumption of green tea enables the body to maintain a high level of tea polyphenols and this paper is the first pharmacological evidence of a wide distribution of [3H]EGCG in mouse organs, indicating a similar wide range of target organs for cancer prevention in humans.
Article
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. 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. 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. 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.
Article
Selenium, an essential biological trace element, has been shown to reduce and prevent the incidence of cancer. Our previous studies have shown that selenite is involved in the chemoprevention of cancer and induction of apoptosis of cancer cells. In this study, we demonstrate that selenite also inhibits the invasion of tumor cells. Cancer cell invasion requires coordinated processes, such as changes in cell-cell and cell-matrix adhesion, degradation of the extracellular matrix, and cell migration. We found that selenite inhibited invasion of HT1080 human fibrosarcoma cells. Adhesion of HT1080 cells to the collagen matrix was also inhibited by treatment with selenite, but cell-cell interaction and cell motility were not affected by selenite. Moreover, selenite reduced expression of matrix metalloproteinase-2 and -9 and urokinase-type plasminogen activator, which are involved in matrix degradation, but increased a tissue inhibitor of metalloproteinase-1. This inhibitory effect of selenite on the protease expressions was mediated by the suppression of transcription factors, NF-κB and AP-1. However, selenate showed no remarkable effect on all the steps of cancer cell invasion.
Article
MMPs play a crucial role in the process of cancer invasion and metastasis. The influence of NAC on invasion and MMP-9 production of human bladder cancer cell line T24 was investigated using an in vitro invasion assay, gelatin zymography, Western and Northern blot analyses and RT-PCR assays. TPA increased the number of invading T24 cells through reconstituted basement membrane more than 10-fold compared to basal condition. NAC inhibited TPA-enhanced invasion dose-dependently. TPA increased the MMP-9 production by T24 cells without altering expression of TIMP-1 gene, while NAC suppressed TPA-enhanced production of MMP-9. Neither TPA nor NAC altered TIMP-1 mRNA level in T24 cells. In vitro experiments demonstrated that MMP-9 was directly inhibited by NAC but was not influenced by TPA. NAC limits invasion of T24 human bladder cancer cells by inhibiting the MMP-9 production in addition to a direct inhibition of MMP-9 activity.
Article
Epigallocatechin-3-gallate (EGCG), one of the components of green tea, has been suggested to have antiviral activity. To determine the effects of EGCG on HIV infection, peripheral blood lymphocytes were incubated with either LAI/IIIB or Bal HIV strains and increasing concentrations of EGCG. EGCG strongly inhibited the replication of both virus strains as determined by reverse transcriptase and p24 assays on the cell supernatants.
Article
This review is intended to provide a fundamental perspective on the dynamic interplay between HIV-1 and the immune system, an essential aspect in defining the pathogenesis and treatment of AIDS. HIV-1 infection, the cause of AIDS, is a worldwide pandemic with enormous adverse heath and economic implications, particularly in the developing world. This bloodborne and sexually transmitted disease, which evolved from simian immunodeficiency virus, infects and replicates in helper T cells and macrophages and utilizes CD4 and a chemokine coreceptor for entry. Immune deficiency occurs as a result of virally induced attrition of CD4 T cells, resulting in the development of opportunistic infections and malignancy. Prophylaxis against opportunistic infections is required according to the extent of immune deficiency. HIV-specific immunity can control viral replication and delay disease progression but does not clear infection. Antiretroviral treatment consists of inhibitors that target for viral entry, reverse transcriptase, and viral protease. Therapy can control viral replication, restore immunity, and delay disease progression, but it cannot eliminate infection. Thus chronic infection persists even in treated patients. Antiretroviral drugs have been highly effective in preventing mother-to-child transmission and for postexposure prophylaxis. Several novel vaccines in development hold promise for either effective infection prevention or attenuation of disease progression.
Article
Although green tea polyphenol catechin has been reported to have antiallergic and anti-inflammatory activities, the precise mechanisms of its effect on the immune system have been poorly investigated. In this study, we aimed to elucidate the mechanisms of the anti-inflammatory effect of catechin. For this purpose, we studied the effect of 2 kinds of catechin, epigallocatechin gallate (EGCG) and epicatechin gallate, on peripheral blood CD8+ T cells, which play the key role in immune responses. Isolated peripheral blood mononuclear cells or CD8+ T cells were incubated without or with catechin, and the changes in the surface expression of integrin molecules were investigated by flow cytometry and the direct binding of catechin to CD11b molecule by competitive ELISA. Also, the effect of catechin on the ability of CD8+ T cells to bind intracellular adhesion molecule 1 and to migrate in response to chemokines was evaluated by using the adhesion and migration assays. The 2 catechins directly bound to CD11b expressed on CD8+ T cells, which caused a consequent decrease of flow-cytometric CD11b expression. The effect was more prominent with EGCG than epicatechin gallate, and the impaired expression of CD11b induced by EGCG resulted in decreased ability of CD8+ T cells to adhere intercellular adhesion molecule 1, and consequently decreased migration in response to chemokines. We concluded that catechin, especially EGCG, by downregulating CD11b expression on CD8+ T cells and, in consequence, inhibiting infiltration of these cells into the sites of inflammation, is a promising new potent anti-inflammatory agent.
Article
The green tea flavonoid, epigallocatechin gallate (EGCG), has been proposed to have an anti-HIV-1 effect by preventing the binding of HIV-1 glycoprotein (gp) 120 to the CD4 molecule on T cells. To demonstrate that EGCG binds to the CD4 molecule at the gp120 attachment site and inhibits gp120 binding at physiologically relevant levels, thus establishing EGCG as a potential therapeutic treatment for HIV-1 infection. Nuclear magnetic resonance spectroscopy was used to examine the binding of EGCG and control, (-)-catechin, to CD4-IgG2 (PRO 542). Gp120 binding to human CD4+ T cells was analyzed by flow cytometry. Addition of CD4 to EGCG produced a linear decrease in nuclear magnetic resonance signal intensity from EGCG but not from the control, (-)-catechin. In saturation transfer difference experiments, addition of 5.8 micromol/L CD4 to 310 micromol/L EGCG produced strong saturation at the aromatic rings of EGCG, but identical concentrations of (-)-catechin produced much smaller effects, implying EGCG/CD4 binding strong enough to reduce gp120/CD4 binding substantially. Molecular modeling studies suggested a binding site for EGCG in the D1 domain of CD4, the pocket that binds gp120. Physiologically relevant concentrations of EGCG (0.2 micromol/L) inhibited binding of gp120 to isolated human CD4+ T cells. We have demonstrated clear evidence of high-affinity binding of EGCG to the CD4 molecule with a Kd of approximately 10 nmol/L and inhibition of gp120 binding to human CD4+ T cells. Epigallocatechin gallate has potential use as adjunctive therapy in HIV-1 infection.
Article
(-)Epigallocatechin-3-gallate (EGCG), a green tea component, has been attributed with anticarcinogenic and antioxidant activities. The extent and rate of absorption of EGCG by the small intestine depends on various factors such as molecular size, lipophilicity, solubility, pKa, gastric and intestinal transit time, lumen pH, membrane permeability and first pass metabolism. The bioavailability of EGCG can be increased by decreasing the presystemic elimination by stabilizing EGCG in the lumen, helping its transfer across the intestinal apical membrane and its accumulation and thus its availability by inhibiting phase I and II enzymes and phase III transporters. In a crossover study, five human volunteers were given a single oral dose of GTE (A), nutrient mixture (NM) containing GTE (B) and formulation B along with black grapes 250 g (C). Blood samples were drawn at 0, 2, 4, 6 and 8 h. The pharmacokinetic parameters were analysed by WinNonLin (Vs 5.0.1.) using a non-compartmental approach. Supplementation with nutrient mixture normally prescribed to cancer patients containing ascorbic acid, selenium, N-acetyl cysteine and other nutrients (formulation B) resulted in an increase of the systemic availability of EGCG by 14% and formulation C further increased it by 13%, thus leading to a total increase of 27%. Copyright
Article
To assess the antioxidant status in HIV positive children. HIV positive children under the age group of 3-12 years from lower socio-economic strata were chosen for the study (Group 1). The values were compared with normal children (Group 2) not suffering from any disease in the same age group and similar socio-economic strata. The antioxidants chosen for the present study were vitamin A (Retinol), vitamin C (Ascorbic acid) and vitamin E (alpha tocopherol). Results obtained were subjected to statistical analysis using student 't' test (in the present study 'z' test was applied). The antioxidants vitamin A, C and E decreased in HIV positive children as compared to controls. Vitamin A was significant to the level of p< 0.01 and vitamin C and E to the level of p< 0.001 and p< 0.02 respectively. The decrease in antioxidants A, C and E in HIV positive children is due to increased utilization of antioxidant micronutrients because of increased oxidative stress caused due to free radicals.
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