Nutritional status and immune responses in mice with murine AIDS are normalized by vitamin E supplementation

Effectiveness of a multivitamin supplementation program among HIV-infected adults in Tanzania

OBJECTIVE

The objective of this study was to assess the effectiveness of a routine multivitamin supplementation program for adults living with HIV in Tanzania.

DESIGN

We conducted a retrospective cohort study of 67 707 adults enrolled in the Dar es Salaam HIV care and treatment program during 2004-2012.

METHODS

The Dar es Salaam HIV care and treatment program intended to provide all adult patients with multivitamin supplements (vitamins B-complex, C, and E) free of charge; however, intermittent stockouts and other implementation issues did not afford universal coverage. We use Cox proportional hazard models to assess the time-varying association of multivitamin supplementation with mortality and clinical outcomes.

RESULTS

The study cohort contributed 41 540 and 129 315 person-years of follow-up time to the antiretroviral therapy (ART)-naive and ART-experienced analyses, respectively. Among 48 207 ART-naive adults, provision of multivitamins reduced the risk of mortality [adjusted hazard ratio (aHR): 0.69; 95% confidence interval (CI): 0.59-0.81], incident tuberculosis (TB) (aHR: 0.83; 0.76-0.91), and meeting ART eligibility criteria (aHR: 0.78; 95% CI: 0.73-0.83) after adjustment for time-varying confounding. Among 46 977 ART-experienced patients, multivitamins reduced mortality (hazard ratio: 0.86; 95% CI: 0.80-0.92), incident TB (aHR: 0.78; 95% CI: 0.73-0.84), and immunologic failure (aHR: 0.70; 95% CI: 0.67-0.73). The survival benefits associated with provision multivitamins appeared to be greatest during the first year of ART and declined over time (P value <0.001).

CONCLUSION

Multivitamin supplementation appears to be a simple, effective, safe, and scalable program to improve survival, reduce incidence of TB, and improve treatment outcomes for adult HIV patients in Tanzania.

Nutrition for Multiples

In 2012 there were 135,943 infants of multiple pregnancies born in the United States, nearly a 2-fold increase since 1980, with twins accounting for 96% of all multiple births. To date, most perinatal morbidities associated with multiple births have proven resistant to technological or pharmaceutical interventions. Maternal nutrition can have a profound effect on the course and outcome of multiple pregnancy, with the goal of achieving optimal intrauterine growth and birthweights, and minimizing prenatal and perinatal complications for the mother and her children.

Effect of micronutrient supplementation on disease progression in asymptomatic, antiretroviral-naive, HIV-infected adults in Botswana: a randomized clinical trial

IMPORTANCE

Micronutrient deficiencies occur early in human immunodeficiency virus (HIV) infection, and supplementation with micronutrients may be beneficial; however, its effectiveness has not been investigated early in HIV disease among adults who are antiretroviral therapy (ART) naive.

OBJECTIVE

To investigate whether long-term micronutrient supplementation is effective and safe in delaying disease progression when implemented early in adults infected with HIV subtype C who are ART-naive.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial of supplementation with either daily multivitamins (B vitamins and vitamins C and E), selenium alone, or multivitamins with selenium vs placebo in a factorial design for 24 months. The study was conducted in 878 patients infected with HIV subtype C with a CD4 cell count greater than 350/μL who were not receiving ART at Princess Marina Hospital in Gaborone, Botswana, between December 2004 and July 2009.

INTERVENTIONS

Daily oral supplements of B vitamins and vitamins C and E, selenium alone, or multivitamins plus selenium, compared with placebo.

MAIN OUTCOMES AND MEASURES

Reaching a CD4 cell count less than 200/μL until May 2008; after this date, reaching a CD4 cell count of 250/μL or less, consistent with the standard of care in Botswana for initiation of ART at the time of the study.

RESULTS

There were 878 participants enrolled and randomized into the study. All participants were ART-naive throughout the study. In intent-to-treat analysis, participants receiving the combined supplement of multivitamins plus selenium had a significantly lower risk vs placebo of reaching CD4 cell count 250/μL or less (adjusted hazard ratio [HR], 0.46; 95% CI, 0.25-0.85; P = .01; absolute event rate [AER], 4.79/100 person-years; censoring rate, 0.92; 17 events; placebo AER, 9.22/100 person-years; censoring rate, 0.85; 32 events). Multivitamins plus selenium in a single supplement, vs placebo, also reduced the risk of secondary events of combined outcomes for disease progression (CD4 cell count ≤250/μL, AIDS-defining conditions, or AIDS-related death, whichever occurred earlier [adjusted HR, 0.56; 95% CI, 0.33-0.95; P = .03; AER, 6.48/100 person-years; censoring rate, 0.90; 23 events]). There was no effect of supplementation on HIV viral load. Multivitamins alone and selenium supplementation alone were not statistically different from placebo for any end point. Reported adverse events were adjudicated as unlikely to be related to the intervention, and there were no notable differences in incidence of HIV-related and health-related events among study groups.

CONCLUSIONS AND RELEVANCE

In ART-naive HIV-infected adults, 24-month supplementation with a single supplement containing multivitamins and selenium was safe and significantly reduced the risk of immune decline and morbidity. Micronutrient supplementation may be effective when started in the early stages of HIV disease.

Effects of vitamin e on bone biomechanical and histomorphometric parameters in ovariectomized rats

The present study examined the dose-dependent effect of vitamin E in reversing bone loss in ovariectomized (Ovx) rats. Sprague-Dawley rats were either Sham-operated (Sham) or Ovx and fed control diet for 120 days to lose bone. Subsequently, rats were divided into 5 groups (n = 12/group): Sham, Ovx-control, low dose (Ovx + 300 mg/kg diet; LD), medium dose (Ovx + 525 mg/kg diet; MD), and high dose (Ovx + 750 mg/kg diet; HD) of vitamin E and sacrificed after 100 days. Animals receiving MD and HD of vitamin E had increased serum alkaline phosphatase compared to the Ovx-control group. Bone histomorphometry analysis indicated a decrease in bone resorption as well as increased bone formation and mineralization in the Ovx groups supplemented with MD and HD of vitamin E. Microcomputed tomography findings indicated no effects of vitamin E on trabecular bone of fifth lumbar vertebrae. Animals receiving HD of vitamin E had enhanced fourth lumbar vertebra quality as evidenced by improved ultimate and yield load and stress when compared to Ovx-control group. These findings demonstrate that vitamin E improves bone quality, attenuates bone resorption, and enhances the rate of bone formation while being unable to restore bone density and trabecular bone structure.

Beneficial actions of melatonin in the management of viral infections: a new use for this "molecular handyman"?

Melatonin (N‐acetyl‐5‐methoxytryptamine) is a multifunctional signaling molecule that has a variety of important functions. Numerous clinical trials have examined the therapeutic usefulness of melatonin in different fields of medicine. Clinical trials have shown that melatonin is efficient in preventing cell damage under acute (sepsis, asphyxia in newborns) and chronic states (metabolic and neurodegenerative diseases, cancer, inflammation, aging). The beneficial effects of melatonin can be explained by its properties as a potent antioxidant and antioxidant enzyme inducer, a regulator of apoptosis and a stimulator of immune functions. These effects support the use of melatonin in viral infections, which are often associated with inflammatory injury and increases in oxidative stress. In fact, melatonin has been used recently to treat several viral infections, which are summarized in this review. The role of melatonin in infections is also discussed herein. Copyright © 2012 John Wiley & Sons, Ltd.

Micronutrients and HIV infection

The immune system requires several essential micronutrients to maintain an effective immune response. HIV infection destroys the immune system and promotes nutritional deficiencies, which further impair immunity. This article reviews the role of several micronutrients (vitamins A, C, E and D, the B vitamins, and minerals, selenium, iron and zinc) that are relevant for maintaining immune function. In addition, the deficiencies of these micronutrients have been associated with faster progression of HIV-1 disease. This review examines the evidence from observational studies of an association between micronutrient status and HIV disease, as well as the effectiveness of micronutrient supplementation on HIV-disease progression, pregnancy outcomes and nutritional status, among others, utilizing randomized clinical trials. Each micronutrient is introduced with a summary of its functions in human physiology, followed by the presentation of studies conducted in HIV-infected patients in relation to this specific micronutrient. Overall findings and recommendations are then summarized.

Vitamin E treatment for children with chronic hepatitis B: A randomized placebo controlled trial

AIM: To evaluate the safety and efficacy of vitamin E in children with chronic hepatitis B.

METHODS: We randomly assigned patients with chronic hepatitis B, positive for hepatitis B e antigen (HBeAg), to receive either vitamin E or placebo once daily for 6 mo in a 3:1 ratio and double-blind manner. The primary end point was HBeAg seroconversion, defined as the loss of HBeAg, undetectable levels of serum hepatitis B virus DNA, and the appearance of antibodies against HBeAg 12 mo after therapy.

RESULTS: At baseline visit, 49 patients had normal and 43 had increased serum aminotransferase levels. Twenty-nine patients did not respond to previous treatment with interferon-α or lamivudine. Seventy-six children completed the study; 16 were non-compliant (n = 7), lost to follow-up (n = 7), or started another antiviral treatment (n = 3). Intention-to-treat analysis showed HBeAg seroconversion in 16 children (23.2%) treated with vitamin E and two (8.7%) in the placebo group (P = 0.13). Vitamin E was well tolerated.

CONCLUSION: There is only a tendency that vitamin E may promote HBeAg seroconversion. Therefore larger studies are needed to clarify the role of antioxidants in the therapy of chronic hepatitis B.

The role of vitamin E in reversing bone loss

BACKGROUND AND AIMS

A positive correlation between intake of antioxidants including vitamins E and C on bone mass has been established by a number of investigators. The present study was conducted to evaluate the extent to which higher doses of vitamin E than normal dose (75 IU per kg diet) can reverse bone loss in aged osteopenic orchidectomized male rats.

METHODS

Forty 12-month old male Sprague- Dawley rats were either sham-operated (Sham) or orchidectomized (Orx), and fed control diet for 120 days to establish bone loss. Thereafter, rats were assigned to their corresponding treatment groups (n= 10 per group): Sham and one Orx groups received 75 IU vitamin E and served as controls, and the other two Orx groups received either 250 or 500 IU vitamin E per kg diet for 90 days.

RESULTS

Higher doses of vitamin E did not improve bone mineral density (BMD) or content (BMC) of whole body, femur and lumbar vertebra or alter the orchidectomy-induced deterioration of trabecular microarchitecture of the distal femur metaphysis in comparison with Orx controls that received adequate vitamin E. Biochemical markers of bone formation and bone resorption, i.e. serum osteocalcin and urinary deoxypyridinoline crosslinks, were also unaffected by vitamin E supplementation.

CONCLUSIONS

Overall, the findings of the present study suggest that supplemental doses of vitamin E do not increase BMD values in male rat model of osteoporosis. However, human studies are needed to confirm the population findings indicating that individuals with higher vitamin E intake have higher bone mass.

The Comparative Impact of Iron, the B-Complex Vitamins, Vitamins C and E, and Selenium on Diarrheal Pathogen Outcomes Relative to the Impact Produced by Vitamin A and Zinc

Micronutrient supplementation offers one of the most cost-effective means of improving the health and survival of children in developing countries. However, the effects of supplementation with single micronutrients on diarrhea are not always consistent, and supplementation with multi-micronutrient supplements can have negative effects. These inconsistencies may result from the failure to consider the diverse etiological agents that cause diarrhea and the unique effects each micronutrient has on the immune response to each of these agents. This review examines the separate effects that supplementation with the B-complex vitamins, vitamin C, vitamin E, selenium, and iron have on diarrheal disease-related outcomes. Supplementation with iron may increase the risk of infection by invasive diarrheal pathogens, while supplementation with the remaining micronutrients may reduce this risk. These differences may be due to distinct regulatory effects each micronutrient has on the pathogen-specific immune response, as well as on the virulence of specific pathogens. The findings of these studies suggest that micronutrient supplementation of children must take into account the pathogens prevalent within communities as reflected by their diarrheal disease burdens. The effectiveness of combining multiple micronutrients into one supplement must also be reconsidered.

Efficacy of vitamin E in children with immunotolerant-phase chronic hepatitis B infection

BACKGROUND

The purpose of the present paper was to investigate the efficacy of vitamin E in children with immunotolerant-phase chronic hepatitis B virus (CHB) infection.

METHODS

Fifty-eight immunotolerant children were prospectively and randomly recruited into two groups. Group 1 (study group) included 30 patients who received vitamin E at a dose of 100 mg/day throughout 3 months; group 2 (control group) contained 28 patients who did not receive any medication. Comparison of serological, virologic, and biochemical response ratios were done at the end of the therapy and after 6 months of vitamin E discontinuation.

RESULTS

Mean alanine transaminase (ALT) values in group 1 at the beginning of the therapy, 3 months after the therapy initiation and 6 months after discontinuation were 30.4 +/- 7.3 IU/L, 31.3 +/- 7.8 IU/L and 32.1 +/- 8.5 IU/L, respectively. The mean hepatitis B virus (HBV)-DNA load of group 1 at onset, and at the third and ninth months of the treatment were 3106 +/- 718 pg/mL, 3530 +/- 137 pg/mL and 3364 +/- 1246 pg/mL, respectively. These changes in both ALT and HBV-DNA values did not reach significant levels (P > 0.05). In group 2, mean ALT values at the beginning of therapy, and at the third and ninth months were 28.0 +/- 1.8 IU/L, 34.6 +/- 8.1 IU/L, and 34.1 +/- 7.0 IU/L, respectively (P > 0.05), and mean viral load of HBV-DNA was 4227 +/- 1435 pg/mL, 3368 +/- 2673 pg/mL, and 3018 +/- 2814 pg/mL, respectively (P > 0.05). There was no statistically significant difference between group 1 and group 2 at the third and ninth months in the mean ALT values and viral load of HBV-DNA (P > 0.05). Hepatitis B s antigen and hepatitis B e antigen clearance or hepatitis B s antibody and hepatitis B e antibody seroconversion were not observed in either group.

CONCLUSION

As a first study investigating the effect of vitamin E in children with immunotolerant CHB infection, no beneficial effect could be demonstrated. Different immunomodulator protocols should be considered for future investigations.

Vitamins C and E prevent AZT-induced leukopenia and loss of cellularity in bone marrow. Studies in mice

A major limitation in the use of AZT for AIDS treatment is the occurrence of side effects, such as leukopenia. The effects of antioxidant vitamins C and E on AZT-induced leukopenia were investigated in mice. Mice were divided into four groups: (1) controls; (2) AZT-treated; (3) treated with AZT plus vitamins C and E; and (4) pre-treated with vitamins and then treated with AZT plus vitamins. Our results demonstrate that AZT causes leukopenia in mice, which was abrogated by administration of vitamins C and E in the pre-treated group. These vitamins prevented the decrease in cellular content induced by AZT in bone marrow and diminished peroxide levels in myeloid precursors in bone marrow. AZT also caused an increase in plasma malondialdehyde and blood oxidized glutathione levels, which was prevented by the administration of antioxidant vitamins. In conclusion, oxidative stress is involved in AZT-induced leukopenia which may be prevented by antioxidant treatment.

Effects of vitamins, including vitamin A, on HIV/AIDS patients

An estimated 25 million lives have been lost to acquired immune-deficiency syndrome (AIDS) since the immunodeficiency syndrome was first described in 1981. The progress made in the field of treatment in the form of antiretroviral therapy (ART) for HIV disease/AIDS has prolonged as well as improved the quality of life of HIV-infected individuals. However, access to such treatment remains a major concern in most parts of the world, especially in the developing countries. Hence, there is a constant need to find low-cost interventions to complement the role of ART in prevention of HIV infection and slowing clinical disease progression. Nutritional interventions, particularly vitamin supplementation, have the potential to be a low-cost method for being such an intervention by virtue of their modulation of the immune system. Among all the vitamins, the role of vitamin A has been studied most extensively; most observational studies have found that low vitamin A levels are associated with increased risk of transmission of HIV from mother to child. This finding has not been supported by large randomized trials of vitamin A supplementation; on the contrary, these trials have found that vitamin A supplementation increases the risk of mother-to-child transmission (MTCT). There are a number of potential mechanisms that might explain these contradictory findings. One is the issue of reverse causality in observational studies-for instance, advanced HIV disease may suppress release of vitamin A from the liver. This would lead to low levels of vitamin A in the plasma despite the body having enough vitamin A liver stores. Further, advanced HIV disease is likely to increase the risk of MTCT, and hence it would appear that low serum vitamin A levels are associated with increased MTCT. The HIV genome also has a retinoic acid receptor element-hence, vitamin A may increase HIV replication via interacting with this element, thus increasing risk of MTCT. Finally, vitamin A is known to increase lymphoid cell differentiation, which leads to an increase in CCR5 receptors. These receptors are essential for attachment of HIV to the lymphocytes and therefore, an increase in their number is likely to increase HIV replication. Vitamin A supplementation in HIV-infected children, on the other hand, has been associated with protective effects against mortality and morbidity, similar to that seen in HIV-negative children. The risk for lower respiratory tract infection and severe watery diarrhea has been shown to be lower in HIV-infected children supplemented with vitamin A. All-cause mortality and AIDS-related deaths have also been found to be lower in vitamin A-supplemented HIV-infected children. The benefits of multivitamin supplementation, particularly vitamins B, C, and E, have been more consistent across studies. Multivitamin supplementation in HIV-infected pregnant mothers has been shown to reduce the incidence of adverse pregnancy outcomes such as fetal loss and low birth weight. It also has been shown to decrease rates of MTCT among women who have poor nutritional or immunologic status. Further, multivitamin supplementation reduces the rate of HIV disease progression among patients in early stage of disease, thus delaying the need for ART by prolonging the pre-ART stage. In brief, there is no evidence to recommend vitamin A supplementation of HIV-infected pregnant women; however, periodic vitamin A supplementation of HIV-infected infants and children is beneficial in reducing all-cause mortality and morbidity and is recommended. Similarly, multivitamin supplementation of people infected with HIV, particularly pregnant women, is strongly suggested.

The efficacy of vitamin E against oxidative damage and autoantibody production in systemic lupus erythematosus: a preliminary study

The hypothesis that reactive oxygen species (ROS) modification of DNA is involved in the development of autoantibodies in systemic lupus erythematosus (SLE) is supported by the enhanced reactivity of anti-DNA antibodies to ROS-denatured DNA. We studied the efficacy of vitamin E against both oxidative DNA damage and autoantibody production in SLE. Urinary 8-hydroxydeoxyguanosine (8-OHdG), an indicator of oxidative DNA damage, and the anti-double-stranded DNA (anti-ds DNA) antibody, a predictor of disease activity, were assayed twice, first during the season with the most intense sunlight and then later in the year. Twelve women among 36 outpatients received vitamin E (150 to 300 mg/day) together with prednisolone (PSL). No significant age or daily dose of PSL differences were evident between patient groups. Urinary 8-OHdG in the PSL with vitamin E group (15.0 +/- 10.2 ng/mg during the period of intense sunlight and 11.7 +/- 8.7 ng/mg during the remainder of the year) did not differ significantly from that in the PSL without vitamin E group (20.0 +/- 23.2 and 11.0 +/- 5.9 ng/mg, at these respective times), but the anti-ds DNA antibody titer in the PSL with vitamin E group (17.9 +/- 20.3 IU/l during the period of intense sunlight and 16.3 +/- 19.4 IU/l during the remainder of the year) was significantly lower than that in the PSL without vitamin E group for both sunlight-defined periods (66.3 +/- 76.8 and 55.8 +/- 59.0 IU/l, at these respective times; P < 0.05). The present study suggests that vitamin E can suppress autoantibody production via a mechanism independent of antioxidant activity.

Age and Vitamin E-Induced Changes in Gene Expression Profiles of T Cells

T cells are vulnerable to age-associated changes. Vitamin E has been shown to improve T cell functions in the old. We studied gene expression profiles of T cells to better understand the underlying mechanisms of age and vitamin E-induced changes in T cell function. Young and old C57BL mice were fed diets containing 30 (control) or 500 (supplemented) ppm of vitamin E for 4 wks. Gene expression profiles of T cells were assessed using microarray analysis with/without anti-CD3/anti-CD28 stimulation. Genes associated with cytokines/chemokines, transcriptional regulation, signal transduction, cell cycle, and apoptosis were significantly up-regulated upon stimulation. Higher SOCS3 and lower growth factor independent 1 (Gfi-1) expression in old T cells may contribute to age-associated decline in proliferation. Higher Gadd45 and lower Bcl2 expression may contribute to increased apoptosis in old T cells. Vitamin E supplementation resulted in higher expression of genes involved in cell cycle regulation (Ccnb2, Cdc2, Cdc6) in old T cells. Vitamin E supplementation resulted in higher up-regulation of IL-2 expression in young and old T cells and lower up-regulation of IL-4 expression in old T cells following stimulation. These findings suggest that aging has significant effects on the expression of genes associated with signal transduction, transcriptional regulation, and apoptosis pathways in T cells, and vitamin E has a significant impact on the expression of genes associated with cell cycle and Th1/Th2 balance in old T cells. Further studies are needed to determine whether these changes are due to the effects of aging at a single-cell level or to the shift in the ratio of naïve:memory T cells with age.

Is vitamin E a safe prophylaxis for preeclampsia?

The prophylactic use of vitamins E and C for the prevention of preeclampsia is currently being evaluated in multiple clinical trials in Canada, Mexico, the United Kingdom, the United States, and other developing countries. In addition to its antioxidant capacity, exogenous vitamin E may prevent an immunologic switch (Th1 to Th2) that is vital for early-to late transition in normal pregnancies. Moreover, vitamin E could be a potential interferon-gamma (IFN-gamma) mimic facilitating persistent proinflammatory reactions at the fetal-maternal interface. These untoward effects of dietary intake of vitamin E may be more pronounced in those treated cases that fail to develop preeclampsia. A critical test of this hypothesis would be to establish whether, under variable O2 tension, vitamin E is capable of affecting cytokine signaling in placental trophoblasts and maternal immune effector cells, both in early and late human pregnancies.

Effect of vitamin E supplementation on the regular treatment of seasonal allergic rhinitis

BACKGROUND

Vitamin E supplementation is widely used in clinical practice for the prevention and treatment of different medical conditions. Evidence from basic science studies suggests that vitamin E may reduce immune allergic responses. However, only a few clinical studies of the effect of vitamin E on allergic conditions have been performed in patients with atopic dermatitis and asthma, and none have been performed in patients with allergic rhinitis.

OBJECTIVE

To determine the effect of high-dose vitamin E supplementation in combination with the usual ("real-life") treatment on the symptoms of seasonal allergic rhinitis during the pollen season.

METHODS

In a double-blind, placebo-controlled, randomized study, 112 patients with documented hay fever received either vitamin E (800 mg/d) or placebo in addition to their regular antiallergic treatment during the pollen season. Patients recorded their daily nasal and eye symptoms and their daily need for other medications to control allergic symptoms.

RESULTS

Although no effect was observed on ocular symptoms, nasal symptom scores were lower in patients who received vitamin E supplementation during the hay fever season. However, there was no reduction in the percentage of days with serious symptoms or in the percentage of days that medications were used to control allergic symptoms during the pollen season.

CONCLUSIONS

Vitamin E supplementation may be a valuable addition to the treatment of patients with seasonal allergic rhinitis. However, further clinical and basic science studies are needed to determine its real value.

Prooxidant diet provides protection during murine infection with Toxoplasma gondii

Toxoplasmosis, particularly toxoplasmic encephalitis, has emerged as a major cause of morbidity and mortality in patients with acquired immunodeficiency syndrome. Patients infected with human immunodeficiency virus typically experience chronic oxidative stress, and concurrent infection with the intracellular parasite Toxoplasma gondii would be expected to further exacerbate this condition. The present study was conducted to determine whether vitamin E and selenium supplementation might be beneficial in a murine model of toxoplasmosis. To investigate the effect of these antioxidants on the severity of parasitic infection. Swiss Webster (SW) or C57Bl/6J mice infected with oocysts of the ME49 strain of T. gondii were maintained on diets containing no vitamin E or selenium, no vitamin E and 8 ppm selenium, 400 IU/kg vitamin E plus 8 ppm selenium, or vitamin E and selenium at the levels present in standard rodent chow (16 IU/kg and 0.2 ppm, respectively). The results of the study showed that increased dietary supplementation with vitamin E and selenium resulted in trends toward increased tissue cyst number, tissue pathology, and weight loss during infection. In contrast, both resistant SW and susceptible C57Bl/6J mice fed a deficient diet (complete absence of vitamin E and selenium) showed the lowest mean numbers of tissue cysts and very little evidence of tissue pathology during chronic infection.

Profile of chicken cytokines induced by lipopolysaccharide is modulated by dietary alpha-tocopheryl acetate

Previously, we found that 25 to 50 IU/kg of dietary vitamin E (VE) had very different immunoregulatory effects than high VE levels (200 IU/kg), and we hypothesized that this difference was due to different cytokine profiles. Chicks were fed 0, 30, or 200 IU/kg supplemental VE and percentages of CD4+CD8-, CD4-CD8+, CD4+CD8+, and CD4-CD8- lymphocytes, and the ratio of CD4+/CD8+ lymphocytes was determined. The expression of chicken splenic interleukin-1beta (IL-1beta), myelomonocytic growth factor (MGF), interferon (IFN-gamma), and transforming growth factor-beta (TGFbeta) mRNA was determined by reverse transcription (RT)-PCR after intravenous injection of lipopolysaccharide (LPS). Due to a tendency for increased CD4-CD8+ lymphocytes at 30 IU/kg VE (P=0.072), the CD4+/CD8+ ratio was significantly lower for 30 IU/kg VE compared with 0 IU/kg VE (P=0.041). The VE dose of 200 IU/kg decreased the constitutive (prior to LPS) expression of TGFbeta. The LPS caused an increase in IL-1beta, MGF, and IFNgamma expression at all VE concentrations and had no effect on IL-2 and TGFbeta mRNA expression. Dietary VE decreased MGF mRNA (P=0.049) in a dose-dependent manner but had no effect on the expression of other cytokines. The decreased expression of MGF could explain the immunomodulatory effect of VE in inflammation.

Regulation of IL4 gene expression by T cells and therapeutic perspectives

Interleukin-4 (IL-4) is crucial for the differentiation of naive T helper (T(H)) cells into the T(H)2 effector cells that promote humoral (antibody) immunity and provide protection against intestinal helminths. IL-4 also has a central role in the pathogenesis of allergic inflammation. Many transcription factors are involved in the regulation of expression of the gene encoding IL-4. Initiation of transcription of the gene encoding IL-4 in naive T(H) cells is regulated by the T(H)2-specific transcription factor GATA3, whereas acute expression of the gene encoding IL-4 in T(H)2 cells is mediated by inducible, ubiquitous transcription factors after antigen encounter. This review focuses on acute activation of the gene encoding IL-4 in T cells and discusses therapeutic perspectives at the transcriptional level.

Vitamin E improves bone quality in the aged but not in young adult male mice

It is generally viewed that with advancing age, humans and other animals including mice experience a gradual decline in the rate of bone formation. This, in part, may be due to the rise in oxygen-derived free radical formation. Vitamin E, a strong antioxidant, functions as a free radical scavenger that potentially can suppress bone resorption while stimulating bone formation. Although the effects of vitamin E on immune functions are well documented, there is a paucity of information on its effect on skeletal health in vivo. The purpose of this study was to explore the influence of vitamin E supplementation on bone in young adult and old mice. Six and twenty-four month-old male C57BL/6NIA mice each were divided into two groups and fed a diet containing either adequate (30 mg/kg diet) or high (500 mg/kg diet) levels of vitamin E. Thirty days later, mice were killed and bones were removed for analyses including biomechanical testing using three-point bending and mRNA expressions of insulin-like growth factor-I (IGF-I), osteocalcin, and type 1alpha-collagen using Northern blot. In old but not the young adult mice, high-dose vitamin E enhanced bone quality as evident by improved material and structural bone properties in comparison with adequate. This improved quality was accompanied by increases in bone dry weight, protein, and mRNA transcripts for osteocalcin, type Ialpha-collagen, and IGF-I. These data demonstrate that high-dose vitamin E has pronounced effects on bone quality as well as matrix protein in old mice by augmenting bone matrix protein without reducing bone mineralization as evidenced by unaltered bone density.

Vitamin E inhibits CD95 ligand expression and protects T cells from activation-induced cell death

Apoptosis is a morphologically distinct form of cell death involved in many physiological and pathological processes. Expression of the CD95 (APO-1/Fas) ligand (CD95L) is critically involved in activation-induced cell death (AICD) of activated T cells. Here we show that the natural free radical scavenger vitamin E suppresses the activity of the transcription factors NF-kappa B and AP-1, thus blocking expression of CD95L and preventing T cell AICD. Since AICD is a major cause of T cell depletion in AIDS, we examined 35 HIV-1-positive individuals and found that their T cells are more susceptible to AICD than are T cells isolated from healthy controls. Administration of vitamin E suppresses CD95L mRNA expression and protects T cells of HIV-1-infected individuals from CD95-mediated apoptosis. This evidence that vitamin E can affect T cell survival may merit further clinical investigation.

Micronutrients and vertical transmission of HIV-1

ABSTRACT Vertical transmission of HIV from mother to infant can occur during pregnancy, at the time of delivery, or post-natally through breast-feeding and is a major factor in the continuing spread of HIV infection. Inadequate nutritional status may increase the risk of vertical HIV transmission by influencing mater-nal and child factors for transmission. The potential effects on these factors include impaired systemic immune function in pregnant women, fetuses, and children; an increased rate of clinical, immunologic, and virologic disease progression; impaired epithelial integrity of the placenta and genital tract; increased viral shedding in breast milk from inflammation of breast tissue; increased risk of low birth weight and preterm birth; and impaired gastrointestinal immune function and integrity in fetuses and children. Micronutrient deficiencies are prevalent in many HIV-infected populations, and numerous studies have reported that these deficiencies impair immune responses, weaken epithelial integrity, and are associated with accelerated HIV disease progression. Although low serum vitamin A concentrations were shown to be associated with an increased risk of vertical HIV transmission in prospective cohort studies, randomized, placebo-controlled trials have reported that vitamin A and other vitamin supplements do not appear to have an effect on HIV transmission during pregnancy or the intrapartum period. However, the ability of prenatal and postpartum micronutrient supplements to reduce transmission during the breast-feeding period is still unknown.

Vitamin E as treatment for chronic hepatitis B: results of a randomized controlled pilot trial

BACKGROUND AND AIMS

Interferon-alpha treatment has been the treatment of choice for chronic hepatitis with unpredictable results. Recently, Lamivudine has been licensed for use against HBV infection with good results. Unfortunately, recurrence of viremia after lamivudine withdrawal is common and prolonged treatment can induce the emergence of resistant mutant strains. It has been shown that vitamin E can increase the host immune response, and this may provide protection against infectious diseases.

METHODS

We evaluated vitamin E supplementation as therapy for chronic hepatitis B in a pilot study including 32 patients. Patients were randomly allocated to receive vitamin E at the dose of 300 mg twice daily for 3 months (15 patients) or no treatment (17 patients). They were seen monthly during the first 3 months and thereafter quarterly for additional 12 months.

RESULTS

The two groups were comparable at enrollment. At the end of the study period, alanine aminotransferase (ALT) normalization was observed in 7 (47%) patients in vitamin E group and only in 1 (6%) of the controls (P=0.011); HBV-DNA negativization was observed in 8 (53%) patients in the vitamin E group as compared to 3 (18%) in the control group, respectively (P=0.039). A complete response (normal ALT and negative HBV-DNA) was obtained in 7 (47%) patients taking vitamin E and in none of the controls (P=0.0019).

CONCLUSION

Vitamin E supplementation might be effective in the treatment of chronic hepatitis B.

Dietary vitamin E, IgE concentrations, and atopy

Vitamin E inhibits IgE responses to allergic stimuli in animals. We investigated the relation between dietary vitamin E intake and serum IgE concentrations and atopy, measured as allergen skin sensitisation, in a random sample of 2633 adults. Higher concentrations of vitamin E intake were associated with lower serum IgE concentrations and a lower frequency of allergen sensitisation. These findings may explain the beneficial effect of dietary vitamin E on the incidence of asthma.

Nutritional factors and vertical transmission of HIV-1. Epidemiology and potential mechanisms

Transmission of HIV from mothers to children may occur through the transplacental, intrapartum, or breastfeeding routes. Adequate nutritional status may reduce vertical transmission by affecting several maternal or fetal and child risk factors for transmission including enhancing systemic immune function in the mother or fetus/child; reducing the rate of clinical, immunological, or virological progression in the mother; reducing viral load or the risk of viral shedding in lower genital secretions or breast milk; reducing the risks of low birth weight or prematurity; or by maintaining the integrity of the fetus/child gastrointestinal integrity. In prospective observational studies, low plasma vitamin A levels were associated with higher risks of vertical transmission. However, findings from randomized, controlled trials suggest that supplements of vitamin A or other vitamins are unlikely to have an effect on vertical transmission during pregnancy or the intrapartum period. The effect of other nutrient supplements, such as zinc and selenium, is unknown. Similarly, whether nutrition supplements of mothers during the breastfeeding period has an effect on transmission is unknown. The potential benefits of direct supplementation of children born to HIV-infected women on transmission of HIV, as well as on the risk and severity of childhood infections and mortality, are also important to examine.

Effect of long-term dietary antioxidant supplementation on influenza virus infection

This study compared the effect of vitamin E on the course of influenza infection with that of other antioxidants. (In a previous study we showed that short-term vitamin E supplementation significantly decreased pulmonary viral titer in influenza-infected old mice). Eighteen-month-old C57BL/6NCrlBR mice were fed one of the following semisynthetic diets for 6 months: control, vitamin E supplemented, glutathione supplemented, vitamin E and glutathione supplemented, melatonin supplemented, or strawberry extract supplemented. After influenza virus challenge, mice fed vitamin E-supplemented diet had significantly lower pulmonary viral titers compared to those fed the control diet (10(2.6) vs 10(4.0), p < .05) and were able to maintain their body weight after infection (1.8+/-0.9 g weight loss/5 days postinfection in vitamin E group vs 6.8+/-1.4 g weight loss/5 days postinfection in control group, p < .05). Other antioxidants did not have a significant effect on viral titer or weight loss. There was a significant inverse correlation of weight loss with food intake (r = -.96, p < .01), indicating that the observed weight changes were mainly due to decreased food intake. Pulmonary interleukin (IL)-6, IL-1beta, and tumor necrosis factor (TNF)-alpha levels increased significantly postinfection. The vitamin E group had lower lung IL-6 and TNF-alpha levels following infection compared to the control group. In addition, there was a significant positive correlation between weight loss and lung IL-6 (r = .77, p < .01) and TNF-alpha (r = .68, p < .01) levels. Because IL-6 and TNF-alpha have been shown to contribute to the anorexic effect of infectious agents, the prevention of weight loss by vitamin E might be due to its reduced production of IL-6 and TNF-alpha following infection. Thus, among the antioxidants tested, only vitamin E was effective in reducing pulmonary viral titers and preventing an influenza-mediated decrease in food intake and weight loss. Other dietary antioxidant supplementations that reduced one or more measures of oxidative stress (4-hydroxynonenal, malondialdehyde, and hydrogen peroxide) did not have an effect on viral titer, which suggests that, in addition to its antioxidant activity, other mechanisms might be involved in vitamin E's beneficial effect on lowering viral titer and preventing weight loss.

Antioxidants, cytokines, and influenza infection in aged mice and elderly humans

The age-associated dysregulation of the immune response contributes to higher incidences of infectious diseases in the aged. Of note, there is dysregulation of cytokines, including a change in T helper (Th) 1/Th2 cytokine balance and an increase in production of proinflammatory cytokines. Synthesis of many cytokines is influenced by changes in the cellular oxidant/antioxidant balance. Because vitamin E supplementation reduces oxidative stress and improves the immune response in the aged, a series of experiments was conducted to determine the effect of supplementation with vitamin E and other antioxidants on resistance to influenza infection in aged mice and the role of cytokines in vitamin E-induced increase in resistance to influenza infection. The results of these studies plus findings by other investigators on the effects of age and antioxidants on production of cytokines in human and animal models are reviewed.

Micronutrients and innate immunity

Micronutrients such as zinc, selenium, iron, copper, beta-carotene, vitamins A, C, and E, and folic acid can influence several components of innate immunity. Select micronutrients play an important role in alteration of oxidant-mediated tissue injury, and phagocytic cells produce reactive oxidants as part of the defense against infectious agents. Thus, adequate micronutrients are required to prevent damage of cells participating in innate immunity. Deficiencies in zinc and vitamins A and D may reduce natural killer cell function, whereas supplemental zinc or vitamin C may enhance their activity. The specific effects of micronutrients on neutrophil functions are not clear. Select micronutrients may play a role in innate immunity associated with some disease processes. Future studies should focus on issues such as age-related micronutrient status and innate immunity, alterations of micronutrients in disease states and their effect on innate immunity, and the mechanisms by which micronutrients alter innate immunity.

Vitamin E and immunity

Vitamin E is a potent antioxidant and has an ability to modulate host immune functions. This chapter consists of five parts: (1) vitamin E deficiency and immunity, (2) vitamin E supplementation and immunity, (3) vitamin E and the decreased cellular immunity with aging, (4) vitamin E and T-cell differentiation in the thymus, and (5) vitamin E and acquired immune deficiency syndrome (AIDS). In vitamin E deficiency most of the immune parameters show a downward trend, which is associated with increased infectious diseases and the incidence of tumors. In contrast, vitamin E supplementation has various beneficial effects on the host immune system. The decreased cellular immunity with aging or during the development of AIDS is markedly improved by the intake of a high vitamin E diet. In addition, vitamin E plays an important role in the differentiation of immature T cells in thymus. Vitamin E deficiency induces the decreased differentiation of immature T cells, which results in the early decrease of cellular immunity with aging in spontaneously hypertensive rats. Conversely, vitamin E supplementation induces a higher differentiation of immature T cells via increased positive selection by thymic epithelial cells, which results in the improvement of decreased cellular immunity in the aged. Furthermore, vitamin E supplementation induces the early recovery of thymic atrophy following X-ray irradiation. Taken together, these results suggest that vitamin E is an important nutrient for maintaining the immune system, especially in the aged.

Vitamin E and infectious diseases in the aged

The incidence of infectious diseases, particularly respiratory diseases, increases with age. Age-associated decline in immune function contributes to the increased susceptibility of the aged to infections. Vitamin E supplementation has been shown to improve some aspects of immune function in aged animals and human subjects. The protective effect of vitamin E against viral or bacterial infections in experimentally-challenged young animals has been reported. We investigated the effects of supplementation with vitamin E and other antioxidants on resistance to influenza infection in young and old animals. While vitamin E-supplemented young mice showed only a modest reduction in lung viral titre, vitamin E-supplemented old mice exhibited a highly significant (P < 0.05) reduction in viral lung titre. In subsequent studies, we focused on the mechanism of vitamin E-induced reduction of influenza viral titre. The results of these studies as well as those reported by other investigators on the relationship between vitamin E and infectious diseases will be reviewed.

Effect of dietary vitamin E supplementation on murine nasal allergy

BACKGROUND

Although many studies have reported the effects of dietary vitamin E on the immune response, none so far has assessed its role in nasal allergy.

METHODS

Female BALB/c mice were randomized into two groups and fed a 20% casein diet (control group, 50 mg vitamin E/kg diet) or this diet supplemented with 535 mg vitamin E/kg diet (vitamin E group, 585 mg vitamin E/kg diet) for 4 weeks. During the fifth week, the mice in each group were divided into two subgroups to form a total of four treatment groups: group A (control), group B [control + toluene diisocyanate (TDI) sensitization], group C (vitamin E supplementation), and group D (vitamin E supplementation + TDI sensitization). Groups B and D were treated with two courses of intranasal application of 5% TDI in ethyl acetate, whereas groups A and C were treated with ethyl acetate alone. A week after second sensitization all groups were provoked by applying 2.5% of TDI in the vehicle and nasal allergic responses were observed for 10 minutes. Splenic lymphoproliferation, splenic cell cytokines, and the total serum IgE were measured.

RESULTS

Members of group D had lower (P < 0.01) scores of nasal response and sneezed less frequently (P < 0.01) than those of group B. Similarly, splenic lymphoproliferation and production of IL-4 and IL-5 as well as the total serum IgE levels were lower (P < 0.01) in group D than in group B.

CONCLUSIONS

The results indicate that higher doses of vitamin E supplementation may suppress nasal allergic responses.

Effect of 50- and 100-mg vitamin E supplements on cellular immune function in noninstitutionalized elderly persons

BACKGROUND

It has been suggested that vitamin E can counteract the age-associated decline in cellular immune responsiveness (CIR). Particularly, T helper cell type 1 (Th1) activity, ie, interferon (IFN) gamma-producing Th1 activity and, hence, delayed-type hypersensitivity (DTH) would be enhanced by vitamin E supplementation.

OBJECTIVE

Our aim was to study the effects of 6 mo supplementation with 50 and 100 mg vitamin E on CIR in the elderly.

DESIGN

A double-blind, placebo-controlled trial was conducted in 161 healthy elderly subjects aged 65-80 y. CIR was measured in vivo by means of DTH skin tests and in vitro by assessing the production of interleukin (IL) 2, IFN-gamma (a typical Th1 cytokine), and IL-4 (a typical Th2 cytokine) by peripheral blood mononuclear cells after stimulation with phytohemagglutinin.

RESULTS

Both DTH and IL-2 production showed a trend toward increased responsiveness with increasing dose of vitamin E. However, IFN-gamma production decreased whereas IL-4 production increased in the groups receiving vitamin E. Only the change in the number of positive DTH reactions was borderline significantly larger in the 100-mg vitamin E group than in the placebo group (P = 0.06, Bonferroni adjusted). Subjects receiving 100 mg vitamin E with low baseline DTH reactivity or who were physically less active had a significantly larger increase in the cumulative diameter of the skin induration resulting from the DTH test than did the placebo group (P = 0.03), although this difference was not significant after Bonferroni correction (P = 0.07).

CONCLUSION

Possible beneficial effects of 100-mg vitamin E supplementation may be more pronounced in particular subgroups of elderly subjects.

Ascorbic acid is a potent inhibitor of various forms of T cell apoptosis

This study was designed to examine the effect of ascorbic acid (vitamin C) on various death pathways of mouse T cells. Unlike humans, mice produce their own ascorbic acid and our study tested the effect of additional ascorbic acid on murine T cells. Our data show that three T cell death pathways (growth factor withdrawal-, spontaneous-, and steroid-induced death) were inhibited when T cells were incubated with ascorbic acid. The data show that both activated and resting T cells were responsive to ascorbic acid since both populations were resistant to death stimuli when treated with ascorbic acid. Additionally, effector T cells were more likely to enter S phase if treated with ascorbic acid. Our data implicate ascorbic acid as a potent inhibitor of various forms of T cell death and suggest that vitamin C may function as an immune booster through this mechanism.

Prevention of immune dysfunction and vitamin E loss by dehydroepiandrosterone and melatonin supplementation during murine retrovirus infection

Female C57BL/6 mice infected with the LP-BM5 leukaemia retrovirus developed murine acquired immune-deficiency syndrome (AIDS). Dehydroepiandrosterone (DHEA) and melatonin (MLT) modify immune dysfunction and prevent lipid peroxidation. We investigated whether DHEA and MLT could prevent immune dysfunction, excessive lipid peroxidation, and tissue vitamin E loss induced by retrovirus infection. Retrovirus infection inhibited the release of T helper 1 (Th1) cytokines, stimulated secretion of Th2 cytokines, increased hepatic lipid peroxidation, and induced vitamin E deficiency. Treatment with DHEA or MLT alone, as well as together, largely prevented the reduction of B- and T-cell proliferation as well as of Th1 cytokine secretion caused by retrovirus infection. Supplementation also suppressed the elevated production of Th2 cytokines stimulated by retrovirus infection. DHEA and MLT simultaneously reduced hepatic lipid peroxidation and prevented vitamin E loss. The use of DHEA plus MLT was more effective in preventing retrovirus-induced immune dysfunction than either DHEA or MLT alone. These results suggest that supplementation with DHEA and MLT may prevent cytokine dysregulation, lipid oxidation and tissue vitamin E loss induced by retrovirus infection. Similarly, hormone supplementation also modified immune function and increased tissue vitamin E levels in uninfected mice.

Selected vitamins in HIV infection: a review

In this article we review published studies on the role of serum micronutrient levels in the natural history of HIV infection. Specifically, we have focused on vitamins B12, E, A, and beta-carotene. Deficiencies of one or several of these vitamins have been associated with an accelerated progression of HIV infection to AIDS. Most investigators have used serum micronutrient levels as an indicator of vitamin nutriture. However, serum levels are not always the most sensitive or specific indicators of vitamin status. Nonetheless, serum vitamin levels are relatively easy to obtain and have been studied in various HIV-infected populations in individuals at different stages of disease. Low serum B12 levels have been associated with increased neurologic abnormalities, more rapid HIV disease progression, and increased AZT-related bone marrow toxicity. Low serum vitamin E levels have been associated with an increase in oxidative stress in HIV-infected individuals. However, early studies of vitamin E supplementation suggest that vitamin E may have important immunostimulatory properties. Studies of vitamin A deficiency in HIV-infected populations have shown that low serum vitamin A levels are associated with increased mortality, more rapid disease progression, and increased maternal-fetal transmission. However, there is little evidence that vitamin A supplementation, beyond the correction of deficiency, is beneficial in HIV infection. Finally, several clinical trials of beta-carotene supplementation have failed to show significant or sustained improvements in the immune response of patients with HIV infection or AIDS.

Vitamin E status and immune function

Evidence from animal and human studies indicates that vitamin E plays an important role in the maintenance of the immune system. Even a marginal vitamin E deficiency impairs the immune response, while supplementation with higher than recommended dietary levels of vitamin E enhances humoral and cell-mediated immunity. The current RDA level of vitamin E prevents clinical deficiency syndrome but in some situations, especially in older subjects or in a disease state, fails to maintain optimal host defense. The immunological parameters reviewed are all sensitive to changes in the availability of vitamin E and, therefore, may reflect the vitamin E status of a given individual more accurately than conventional methods.

Serum vitamin E decreases in HIV-seropositive subjects over time

Vitamin E is an important lipid soluble antioxidant that has a number of crucial functions including protecting lipids from oxidative damage. It also may play an important role in enhancing the immune response in subjects with Human Immunodeficiency Virus (HIV) infection. The current study measured the serum level of vitamin E in 121 HIV seropositive subjects with no prior pulmonary complications. Although the mean level was normal at 9.0 +/- 0.5 microg/ml, 22.3% of the subjects had a deficient level of less than 5 microg/ml. In addition, 42 subjects were studied longitudinally and serum vitamin E levels were determined at baseline and 12 months later. The mean serum vitamin E level in this group significantly decreased after 12 months compared with baseline levels (5.9 +/- 0.5 microg/ml compared with 9.6 +/- 0.9 microg/ml, p = 0.001). The CD4 counts also were significantly decreased after 12 months (460.6 +/- 36.0 cells/mm3 versus 390.5 +/- 37.7 cells/mm3, p = 0.032). No significant correlations were observed between the decrease in serum vitamin E and the change in CD4 count, body mass index (BMI), or serum albumin levels over the 12-month period. In conclusion, a significant portion of HIV-seropositive subjects have a deficiency in serum vitamin E early in the course of their disease. Furthermore, there is a significant decrease in serum vitamin E levels in these subjects over 12 months.

Association between serum vitamin A and E levels and HIV-1 disease progression

OBJECTIVE

To examine the associations between serum vitamin A and E levels and risk of progression to three key outcomes in HIV-1 infection: first AIDS diagnosis, CD4+ cell decline to < 200 cells x 10(6)/l, and mortality.

DESIGN

Non-concurrent prospective study.

METHODS

Serum levels of vitamins A and E were measured at the enrollment visit of 311 HIV-seroprevalent homo-/bisexual men participating in the Baltimore/ Washington DC site of the Multicenter AIDS Cohort Study. Cox proportional hazards models were used to estimate the relative hazard of progression to each outcome over the subsequent 9 years, adjusting for several independent covariates.

RESULTS

Men in the highest quartile of serum vitamin E levels (> or = 23.5 mumol/l) showed a 34% decrease in risk of progression to AIDS compared with those in the lowest quartile [relative hazard (RH), 0.66; 95% confidence interval (CI), 0.41-1.06)]. This effect was statistically significant when comparing the highest quartile of serum vitamin E to the remainder of the cohort (RH, 0.67; 95% CI, 0.45-0.98). Associations between serum vitamin A levels and risk of progression to AIDS were less clear, but vitamin A levels were uniformly in the normal to high range (median = 2.44 mumol/l). Similar trends were observed for each vitamin with mortality as the outcome, but neither vitamin was associated with CD4+ cell decline to < 200 cells x 10(6)/l. Men who reported current use of multivitamin or single vitamin E supplements had significantly higher serum tocopherol levels than those who were not taking supplements (P = 0.0001). Serum retinol levels were unrelated to intake of multivitamin or single vitamin A supplements.

CONCLUSIONS

These data suggest that high serum levels of vitamin E may be associated with slower HIV-1 disease progression, but no relationship was observed between retinol levels and disease progression in this vitamin A-replete population.

Promotion of interleukin-2 activity as a strategy for 'rejuvenating' geriatric immune function

The age-related decline in immune capacities is largely attributable to a decrease in the ability of activated T lymphocytes to achieve efficient clonal expansion. This in turn reflects a decrease in the expression of both interleukin-2 and its receptor. Nutritional/hormonal measures which up-regulate such expression may thus have a 'rejuvenatory' impact on geriatric immune function. Such measures may include: subtoxic selenium intakes, which increase the inducibility of interleukin-2 receptor; high-dose vitamin E and possibly chromium, which may counteract the down-regulatory effect of cAMP on interleukin-2 activity; as well as carotenoids and ascorbic acid. Restoring more youthful serum levels of the hormones DHEA and melatonin may also have a positive effect in this regard. In addition to their likely value for boosting geriatric immune defenses, these measures deserve evaluation as adjuvants to cancer immunotherapies and to drug treatments for HIV infection.

Liver endogenous antioxidant defenses in mice fed AIN-76A diet and infected with murine AIDS

The effects of murine AIDS infection on endogenous antioxidant defenses in mice fed the AIN-76A liquid diet were investigated. C57BL/6 female mice were divided into 2 groups: one group was injected interperitoneally with LP-BM5 murine retrovirus (MAIDS) stock, and the other group served as the non-infected control. Two weeks after the infection, the mice were killed and livers were excised for biochemical analysis of the antioxidant defenses. Liver reduced glutathione (GSH) levels and activities of both cytosolic superoxide dismutase (SOD) and mitochondrial SOD were significantly depressed by MAIDS infection. Activities of glutathione reductase (GR) selenium (Se)-dependent glutathione peroxidase (GPx), catalase and glutathione-S-transferase (GST) toward 1-chloro-2,4-dinitrobenzene (CDNB) were not affected by MAIDS infection. A previous study by this laboratory using the Lieber-DeCarli (L-D) all purpose liquid diet caused a decline in total SOD activity and GPx activity, but not GSH levels. The results suggest that MAIDS infection depresses liver antioxidant defenses; however, MAIDS infection of mice fed the AID-76A liquid diet depresses different liver antioxidant defense parameters when compared to those of the mice fed the L-D all purpose liquid diet.