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2.
Int J Obes (Lond) ; 48(6): 796-807, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38396126

RESUMO

BACKGROUND/OBJECTIVE: Obesity increases maternal morbidity and adversely affects child health. Maternal inflammation may play a role in adverse outcomes. The objective of this study was to determine whether providing a higher dose of antioxidant micronutrients to pregnant women with obesity would raise concentrations of key antioxidant vitamins and impact inflammation and oxidative stress during pregnancy. SUBJECTS/METHODS: This was a double-blind, randomized controlled trial. We recruited pregnant women with a body mass index (BMI) ≥ 30 kg/m2 at their initial prenatal visit ( < 13 weeks gestation) and collected blood and urine samples at baseline, 24-28 weeks, and 32-36 weeks to measure micronutrient concentrations (vitamin C, E, B6 and folate), markers of inflammation (C-reactive protein, interleukin-6, 8, and 1ß) and oxidative stress (8-epi-PGF2α and malondialdehyde). We collected maternal and infant health data from enrollment to delivery as secondary outcomes. We enrolled 128 participants (64 in each arm), and 98 (49 in each arm) completed follow-up through delivery. INTERVENTION: Both groups received a standard prenatal vitamin containing the recommended daily allowance of micronutrients in pregnancy. In addition, the intervention group received a supplement with 90 mg vitamin C, 30 αTU vitamin E, 18 mg vitamin B6, and 800 µg folic acid, and the control group received a placebo. RESULTS: The intervention group had higher vit B6 (log transformed (ln), ß 24-28 weeks: 0.76 nmol/L (95% CI: 0.40, 1.12); ß 32-36 weeks: 0.52 nmol/L (95% CI: 0.17, 0.88)) than the control group. Vitamins C, E, erythrocyte RBC folate concentrations did not differ by randomization group. The intervention did not impact biomarkers of inflammation or oxidative stress. There were no differences in maternal or neonatal clinical outcomes by randomization group. CONCLUSIONS: Higher concentrations of antioxidant vitamins during pregnancy increased specific micronutrients and did not impact maternal inflammation and oxidative stress, which may be related to dosing or type of supplementation provided. CLINICAL TRIAL REGISTRATION: Clinical Trial Identification Number: NCT02802566; URL of the Registration Site: www. CLINICALTRIALS: gov .


Assuntos
Antioxidantes , Suplementos Nutricionais , Micronutrientes , Estresse Oxidativo , Humanos , Feminino , Gravidez , Método Duplo-Cego , Micronutrientes/administração & dosagem , Antioxidantes/administração & dosagem , Adulto , Estresse Oxidativo/efeitos dos fármacos , Obesidade/sangue , Obesidade/complicações , Complicações na Gravidez/sangue , Complicações na Gravidez/tratamento farmacológico , Biomarcadores/sangue
3.
Front Nutr ; 10: 1230061, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37899826

RESUMO

Introduction: The safety of novel forms of iron in healthy, iron-replete adults as might occur if used in population-based iron supplementation programs was examined. We tested the hypotheses that supplementation with nanoparticulate iron hydroxide adipate tartrate (IHAT), an iron-enriched Aspergillus oryzae product (ASP), or ferrous sulphate heptahydrate (FS) are safe as indicated by erythrocyte susceptibility to malarial infection, bacterial proliferation, and gut inflammation. Responses to FS administered daily or weekly, and with or without other micronutrients were compared. Methods: Two phases of randomized, double-blinded trials were conducted in Boston, MA. Phase I randomized 160 volunteers to six treatments: placebo, IHAT, ASP, FS, and FS plus a micronutrient powder (MNP) administrated daily at 60 mg Fe/day; and FS administered as a single weekly dose of 420 mg Fe. Phase II randomized 86 volunteers to IHAT, ASP, or FS administered at 120 mg Fe/day. Completing these phases were 151 and 77 participants, respectively. The study was powered to detect effects on primary endpoints: susceptibility of participant erythrocytes to infection by Plasmodium falciparum, the proliferation potential of selected pathogenic bacteria in sera, and markers of gut inflammation. Secondary endpoints for which the study was not powered included indicators of iron status and gastrointestinal symptoms. Results: Supplementation with any form of iron did not affect any primary endpoint. In Phase I, the frequency of gastrointestinal symptoms associated with FS was unaffected by dosing with MNP or weekly administration; but participants taking IHAT more frequently reported abdominal pain (27%, p < 0.008) and nausea (4%, p = 0.009) than those taking FS, while those taking ASP more frequently reported nausea (8%, p = 0.009). Surprisingly, only 9% of participants taking IHAT at 120 mg Fe/day (Phase II) reported abdominal pain and no other group reported that symptom. Discussion: With respect to the primary endpoints, few differences were found when comparing these forms of iron, indicating that 28 days of 60 or 120 mg/day of IHAT, ASP, or FS may be safe for healthy, iron-replete adults. With respect to other endpoints, subjects receiving IHAT more frequently reported abdominal pain and nausea, suggesting the need for further study. Clinical Trial Registration: ClinicalTrials.gov, NCT03212677; registered: 11 July 2017.

4.
Adv Nutr ; 13(5): S1-S26, 2022 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-36183242

RESUMO

The immune system is key to host defense against pathogenic organisms. Aging is associated with changes in the immune system, with a decline in protective components (immunosenescence), increasing susceptibility to infectious disease, and a chronic elevation in low-grade inflammation (inflammaging), increasing the risk of multiple noncommunicable diseases. Nutrition is a determinant of immune cell function and of the gut microbiota. In turn, the gut microbiota shapes and controls the immune and inflammatory responses. Many older people show changes in the gut microbiota. Age-related changes in immune competence, low-grade inflammation, and gut dysbiosis may be interlinked and may relate, at least in part, to age-related changes in nutrition. A number of micronutrients (vitamins C, D, and E and zinc and selenium) play roles in supporting the function of many immune cell types. Some trials report that providing these micronutrients as individual supplements can reverse immune deficits in older people and/or in those with insufficient intakes. There is inconsistent evidence that this will reduce the risk or severity of infections including respiratory infections. Probiotic, prebiotic, or synbiotic strategies that modulate the gut microbiota, especially by promoting the colonization of lactobacilli and bifidobacteria, have been demonstrated to modulate some immune and inflammatory biomarkers in older people and, in some cases, to reduce the risk and severity of gastrointestinal and respiratory infections, although, again, the evidence is inconsistent. Further research with well-designed and well-powered trials in at-risk older populations is required to be more certain about the role of micronutrients and of strategies that modify the gut microbiota-host relationship in protecting against infection, especially respiratory infection.


Assuntos
Doenças Transmissíveis , Microbioma Gastrointestinal , Imunossenescência , Infecções Respiratórias , Selênio , Idoso , Humanos , Inflamação , Micronutrientes/metabolismo , Vitaminas , Zinco
5.
Adv Nutr ; 13(5): 1415-1430, 2022 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-35587877

RESUMO

The immune system is weakened by advancing age, often referred to as immunosenescence, increasing the vulnerability to, and frequently the severity of, infectious diseases in older people. This has become very apparent in the current coronavirus disease 2019 (COVID-19) pandemic for which older people are at higher risk of severe outcomes, even those who are fully vaccinated. Aging affects both the innate and adaptive immune systems and is characterized by an imbalanced inflammatory response. Increasing evidence shows that optimal status of nutrients such as vitamins C, D, and E and selenium and zinc as well as the omega-3 (n-3) fatty acids DHA and EPA can help compensate for these age-related changes. While inadequate intakes of these nutrients are widespread in the general population, this is often more pronounced in older people. Maintaining adequate intakes is a challenge for them due to a range of factors such as physical, physiological, and cognitive changes; altered absorption; and the presence of noncommunicable diseases. While nutritional requirements are ideally covered by a balanced diet, this can be difficult to achieve, particularly for older people. Fortified foods and nutritional complements are effective in achieving adequate micronutrient intakes and should be considered as a safe and cost-effective means for older people to improve their nutritional status and hence support their defense against infections. Complementing the diet with a combination of micronutrients, particularly those playing a key role in the immune system such as vitamins C, D, and E and selenium and zinc as well as DHA and EPA, is recommended for older people. Optimal nutrition to support the immune system in older people will remain essential, particularly in the face of the current COVID-19 pandemic and, thus, developing strategies to ensure adequate nutrition for the growing number of older adults will be an important and cost-effective investment in the future.


Assuntos
COVID-19 , Ácidos Graxos Ômega-3 , Selênio , Idoso , Ácido Ascórbico , Humanos , Micronutrientes , Pandemias , Vitaminas , Zinco/uso terapêutico
6.
Gates Open Res ; 3: 1510, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33655197

RESUMO

The forms of iron currently available to correct iron deficiency have adverse effects, including infectious diarrhea, increased susceptibility to malaria, inflammation and detrimental changes to the gut microbiome. These adverse effects limit their use such that the growing burden of iron deficiency has not abated in recent decades. Here, we summarize the protocol of the "Safe Iron Study", the first clinical study examining the safety and efficacy of novel forms of iron in healthy, iron-replete adults. The Safe Iron Study is a double-blind, randomized, placebo-controlled trial conducted in Boston, MA, USA. This study compares ferrous sulfate heptahydrate (FeSO 4·H 2O) with two novel forms of iron supplements (iron hydroxide adipate tartrate (IHAT) and organic fungal iron metabolite (Aspiron™ Natural Koji Iron)). In Phase I, we will compare each source of iron administrated at a low dose (60 mg Fe/day). We will also determine the effect of FeSO 4 co-administrated with a multiple micronutrient powder and weekly administration of FeSO 4. The forms of iron found to produce no adverse effects, or adverse effects no greater than FeSO 4 in Phase I, Phase II will evaluate a higher, i.e., a therapeutic dose (120 mg Fe/day). The primary outcomes of this study include ex vivo malaria ( Plasmodium falciparum) infectivity of host erythrocytes, ex vivo bacterial proliferation (of selected species) in presence of host plasma and intestinal inflammation assessed by fecal calprotectin. This study will test the hypotheses that the novel forms of iron, administered at equivalent doses to FeSO 4, will produce similar increases in iron status in iron-replete subjects, yet lower increases in ex vivo malaria infectivity, ex vivo bacterial proliferation, gut inflammation. Ultimately, this study seeks to contribute to development of safe and effective forms of supplemental iron to address the global burden of iron deficiency and anemia. Registration: ClinicalTrials.gov identifier: NCT03212677; registered: 11 July 2017.

7.
Br J Nutr ; 119(12): 1393-1399, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29845904

RESUMO

Blueberry, rich in antioxidant and anti-inflammatory phytochemicals, has been demonstrated to lower inflammatory status in adipose induced by high-fat diet (HFD) and obesity. The effect of blueberry on systemic immune functions has not been examined. C57BL/6 mice were randomised to one of three diets - low-fat diet (LFD), HFD and HFD plus 4 % (w/w) blueberry (HFD+B) - for 8 or 12 weeks. Ex vivo T-cell mitogens (concanavalin A (Con A); phytohaemagglutinin), T-cell antibody (anti-CD3; anti-CD3/CD28)-stimulated T-cell proliferation and cytokine production were assessed. After 8 weeks, both HFD groups weighed more (>4 g) than the LFD group; after 12 weeks, HFD+B-fed mice weighed more (>6 g) and had 41 % more adipose tissue than HFD-fed mice (P<0·05). After 12 weeks, T-cell proliferation was less in both HFD groups, compared with the LFD group. HFD-associated decrements in T-cell proliferation were partially (10-50 %) prevented by blueberry supplementation. At 12 weeks, splenocytes from HFD mice, but not from HFD+B mice, produced 51 % less IL-4 (CD3/CD28) and 57 % less interferon-γ (Con A) compared with splenocytes from LFD mice (P<0·05). In response to lipopolysaccharide challenge, splenocytes from both HFD groups produced 24-30 % less IL-6 and 27-33 % less TNF-α compared with splenocytes from LFD mice (P<0·05), indicating impaired acute innate immune response. By demonstrating deleterious impacts of HFD feeding on T-cell proliferation and splenocyte immune responses, our results provide insights into how HFD/obesity can disrupt systemic immune function. The protective effects of blueberry suggest that dietary blueberry can buttress T-cell and systemic immune function against HFD-obesity-associated insults.


Assuntos
Mirtilos Azuis (Planta) , Suplementos Nutricionais , Obesidade/dietoterapia , Obesidade/imunologia , Linfócitos T/imunologia , Adiposidade , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Proliferação de Células , Citocinas/biossíntese , Dieta com Restrição de Gorduras , Dieta Hiperlipídica/efeitos adversos , Imunidade Celular , Imunossupressores/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Linfócitos T/patologia , Aumento de Peso
8.
Artigo em Inglês | MEDLINE | ID: mdl-28516066

RESUMO

Despite the availability of vaccines, Streptococcus pneumoniae remains a leading cause of life-threatening infections, such as pneumonia, bacteremia and meningitis. Polymorphonuclear leukocytes (PMNs) are a key determinant of disease course, because optimal host defense requires an initial robust pulmonary PMN response to control bacterial numbers followed by modulation of this response later in infection. The elderly, who manifest a general decline in immune function and higher basal levels of inflammation, are at increased risk of developing pneumococcal pneumonia. Using an aged mouse infection model, we previously showed that oral supplementation with the alpha-tocopherol form of vitamin E (α-Toc) decreases pulmonary inflammation, in part by modulating neutrophil migration across lung epithelium into alveolar spaces, and reverses the age-associated decline in resistance to pneumococcal pneumonia. The objective of this study was to test the effect of α-Toc on the ability of neutrophils isolated from young (22-35 years) or elderly (65-69 years) individuals to migrate across epithelial cell monolayers in response to S. pneumoniae and to kill complement-opsonized pneumococci. We found that basal levels of pneumococcal-induced transepithelial migration by PMNs from young or elderly donors were indistinguishable, suggesting that the age-associated exacerbation of pulmonary inflammation is not due to intrinsic properties of PMNs of elderly individuals but rather may reflect the inflammatory milieu of the aged lung. Consistent with its anti-inflammatory activity, α-Toc treatment diminished PMN migration regardless of donor age. Unexpectedly, unlike previous studies showing poor killing of antibody-opsonized bacteria, we found that PMNs of elderly donors were more efficient at killing complement-opsonized bacteria ex vivo than their younger counterparts. We also found that the heightened antimicrobial activity in PMNs from older donors correlated with increased activity of neutrophil elastase, a serine protease that is required to kill pneumococci. Notably, incubation with α-Toc increased PMN elastase activity from young donors and boosted their ability to kill complement-opsonized pneumococci. These findings demonstrate that α-Toc is a potent modulator of PMN responses and is a potential nutritional intervention to combat pneumococcal infection.


Assuntos
Elastase de Leucócito/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Pneumonia Pneumocócica/imunologia , Streptococcus pneumoniae/imunologia , alfa-Tocoferol/farmacologia , Administração Oral , Adulto , Fatores Etários , Idoso , Animais , Anti-Infecciosos/farmacologia , Catepsina G/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Modelos Animais de Doenças , Epitélio/imunologia , Epitélio/microbiologia , Humanos , Inflamação/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Fagocitose , Pneumonia Pneumocócica/microbiologia , Serina Proteases/efeitos dos fármacos , Streptococcus pneumoniae/patogenicidade , Vitamina E/química , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/química
9.
Am J Clin Nutr ; 103(3): 942-51, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26817502

RESUMO

BACKGROUND: Zinc is essential for the regulation of immune response. T cell function declines with age. Zinc supplementation has the potential to improve the serum zinc concentrations and immunity of nursing home elderly with a low serum zinc concentration. OBJECTIVE: We aimed to determine the effect of supplementation with 30 mg Zn/d for 3 mo on serum zinc concentrations of zinc-deficient nursing home elderly. DESIGN: This was a randomized, double-blind, placebo-controlled study. Of 53 nursing home elderly (aged ≥65 y) who met eligibility criteria, 58% had a low serum zinc concentration (serum zinc <70 µg/dL); these 31 were randomly assigned to zinc (30 mg Zn/d) (n = 16) or placebo (5 mg Zn/d) (n = 15) groups. The primary outcome measure was change in serum zinc concentrations between baseline and month 3. We also explored the effects of supplementation on immune response. RESULTS: Baseline characteristics were similar in the 2 groups. The difference in the mean change in serum zinc was significantly higher, by 16%, in the zinc group than in the placebo group (P = 0.007) when baseline zinc concentrations were controlled for. In addition, controlling for baseline C-reactive protein, copper, or albumin did not change the results. However, supplementation of participants with ≤60 µg serum Zn/dL failed to increase their serum zinc to ≥70 µg/dL. Zinc supplementation also significantly increased anti-CD3/CD28 and phytohemagglutinin-stimulated T cell proliferation, and the number of peripheral T cells (P < 0.05). When proliferation was expressed per number of T cells, the significant differences between groups were lost, suggesting that the zinc-induced enhancement of T cell proliferation was mainly due to an increase in the number of T cells. CONCLUSIONS: Zinc supplementation at 30 mg/d for 3 mo is effective in increasing serum zinc concentrations in nursing home elderly; however, not all zinc-deficient elderly reached adequate concentrations. The increase in serum zinc concentration was associated with the enhancement of T cell function mainly because of an increase in the number of T cells.


Assuntos
Envelhecimento , Proliferação de Células/efeitos dos fármacos , Suplementos Nutricionais , Ativação Linfocitária/efeitos dos fármacos , Linfócitos T/metabolismo , Oligoelementos/farmacologia , Zinco/farmacologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Envelhecimento/imunologia , Deficiências Nutricionais/sangue , Deficiências Nutricionais/prevenção & controle , Método Duplo-Cego , Feminino , Instituição de Longa Permanência para Idosos , Humanos , Masculino , Casas de Saúde , Oligoelementos/sangue , Oligoelementos/deficiência , Oligoelementos/uso terapêutico , Zinco/sangue , Zinco/deficiência , Zinco/uso terapêutico
10.
J Immunol ; 194(3): 1090-9, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25512603

RESUMO

Streptococcus pneumoniae infections are an important cause of morbidity and mortality in older patients. Uncontrolled neutrophil-driven pulmonary inflammation exacerbates this disease. To test whether the α-tocopherol (α-Toc) form of vitamin E, a regulator of immunity, can modulate neutrophil responses as a preventive strategy to mitigate the age-associated decline in resistance to S. pneumoniae, young (4 mo) and old (22-24 mo) C57BL/6 mice were fed a diet containing 30-PPM (control) or 500-PPM (supplemented) α-Toc for 4 wk and intratracheally infected with S. pneumoniae. Aged mice fed a control diet were exquisitely more susceptible to S. pneumoniae than young mice. At 2 d postinfection, aged mice suffered 1000-fold higher pulmonary bacterial burden, 2.2-fold higher levels of neutrophil recruitment to the lung, and a 2.25-fold higher rate of lethal septicemia. Strikingly, α-Toc supplementation of aged mice resulted in a 1000-fold lower bacterial lung burden and full control of infection. This α-Toc-induced resistance to pneumococcal challenge was associated with a 2-fold fewer pulmonary neutrophils, a level comparable to S. pneumoniae-challenged, conventionally fed young mice. α-Toc directly inhibited neutrophil egress across epithelial cell monolayers in vitro in response to pneumococci or hepoxilin-A3, an eicosanoid required for pneumococcus-elicited neutrophil trans-epithelial migration. α-Toc altered expression of multiple epithelial and neutrophil adhesion molecules involved in migration, including CD55, CD47, CD18/CD11b, and ICAM-1. These findings suggest that α-Toc enhances resistance of aged mice to bacterial pneumonia by modulating the innate immune response, a finding that has potential clinical significance in combating infection in aged individuals through nutritional intervention.


Assuntos
Suscetibilidade a Doenças/imunologia , Infiltração de Neutrófilos/efeitos dos fármacos , Infiltração de Neutrófilos/imunologia , Pneumonia Pneumocócica/imunologia , Streptococcus pneumoniae/imunologia , alfa-Tocoferol/farmacologia , Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Ácido 8,11,14-Eicosatrienoico/farmacologia , Fatores Etários , Animais , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Suplementos Nutricionais , Modelos Animais de Doenças , Resistência à Doença/efeitos dos fármacos , Resistência à Doença/imunologia , Epitélio/efeitos dos fármacos , Epitélio/imunologia , Expressão Gênica , Masculino , Camundongos , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Pneumonia Pneumocócica/patologia , Migração Transendotelial e Transepitelial/efeitos dos fármacos , Migração Transendotelial e Transepitelial/imunologia , alfa-Tocoferol/administração & dosagem
11.
Clin Vaccine Immunol ; 20(8): 1123-32, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23720367

RESUMO

Immunization and nutritional interventions are mainstays of child health programs in sub-Saharan Africa, yet few published data exist on their interactions. HIV-exposed (but uninfected) infants enrolled in a randomized placebo-controlled trial of multivitamin supplements (vitamins B complex, C, and E) conducted in Tanzania were sampled for an assessment of measles IgG quantity and avidity at 15 to 18 months. Infants were vaccinated between 8.5 and 12 months of age, and all mothers received high-dose multivitamins as the standard of care. Of 201 HIV-exposed infants who were enrolled, 138 (68.7%) were seropositive for measles. There were no effects of infant multivitamin supplementation on measles seroconversion proportions, IgG concentrations, or IgG avidity (P > 0.05). The measles seroconversion proportion was greater for HIV-exposed infants vaccinated at 10 to 11 months of age than for those vaccinated at 8.5 to 10 months (P = 0.032) and greater for infants whose mothers had a CD4 T-cell count of <200 cells/µl than for infants whose mothers had a CD4 T-cell count of >350 cells/µl (P = 0.039). Stunted infants had a significantly decreased IgG quantity compared to nonstunted infants (P = 0.012). As for measles avidity, HIV-exposed infants vaccinated at 10 to 11 months had increased antibody avidity compared to those vaccinated at 8.5 to 10 months (P = 0.031). Maternal CD4 T-cell counts of <200 cells/µl were associated with decreased avidity compared to counts of >350 cells/µl (P = 0.047), as were lower infant height-for-age z-scores (P = 0.016). Supplementation with multivitamins containing B complex, C, and E does not appear to improve measles vaccine responses for HIV-exposed infants. Studies are needed to better characterize the impact of maternal HIV disease severity on the immune system development of HIV-exposed infants and the effect of malnutrition interventions on vaccine responses. (This study has been registered at ClinicalTrials.gov under registration no. NCT00197730.).


Assuntos
Anticorpos Antivirais/sangue , Infecções por HIV/imunologia , Vacina contra Sarampo/administração & dosagem , Vacina contra Sarampo/imunologia , Vitaminas/administração & dosagem , Adulto , Afinidade de Anticorpos , Contagem de Linfócito CD4 , Feminino , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Placebos/administração & dosagem , Gravidez , Tanzânia , Fatores de Tempo
12.
Am J Pathol ; 180(1): 221-34, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22056360

RESUMO

The green tea component epigallocatechin-3-gallate (EGCG) may be beneficial in autoimmune diseases; however, the underlying mechanisms are not well understood. In this study, we determined the effect of EGCG on the development of experimental autoimmune encephalomyelitis, an animal model for human multiple sclerosis, and the underlying mechanisms. Female C57BL/6 mice were fed EGCG (0%, 0.15%, 0.3%, and 0.6% in diet) for 30 days and then immunized with specific antigen myelin oligodendrocyte glycoprotein 35-55. EGCG dose dependently attenuated clinical symptoms and pathological features (leukocyte infiltration and demyelination) in the central nervous system and inhibited antigen-specific T-cell proliferation and delayed-type hypersensitivity skin response. We further showed that EGCG reduced production of interferon-γ, IL-17, IL-6, IL-1ß, and tumor necrosis factor-α; decreased types 1 and 17 helper T cells (Th1 and Th17, respectively); and increased regulatory T-cell populations in lymph nodes, the spleen, and the central nervous system. Moreover, EGCG inhibited expression of transcription factors T-box expressed in T cells and retinoid-related orphan receptor-γt, the specific transcription factor for Th1 and Th17 differentiation, respectively; the plasma levels of intercellular adhesion molecule 1; and CCR6 expression in CD4(+) T cells. These results indicate that EGCG may attenuate experimental autoimmune encephalomyelitis autoimmune response by inhibiting immune cell infiltration and modulating the balance among pro- and anti-autoimmune CD4(+) T-cell subsets. Thus, we identified a novel mechanism that underlies EGCG's beneficial effect in autoimmune disease.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Catequina/análogos & derivados , Encefalomielite Autoimune Experimental/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Animais , Linfócitos T CD4-Positivos/imunologia , Catequina/farmacologia , Proliferação de Células , Citocinas/metabolismo , Doenças Desmielinizantes/prevenção & controle , Suplementos Nutricionais , Regulação para Baixo , Encefalomielite Autoimune Experimental/imunologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Esclerose Múltipla/imunologia , Esclerose Múltipla/prevenção & controle , Proteínas da Mielina/antagonistas & inibidores , Glicoproteína Mielina-Oligodendrócito , Neurite (Inflamação)/prevenção & controle , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Distribuição Aleatória , Proteínas com Domínio T/antagonistas & inibidores , Subpopulações de Linfócitos T/imunologia
13.
J Am Geriatr Soc ; 59(6): 1093-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21539527

RESUMO

OBJECTIVES: To describe patterns of antimicrobial use for respiratory tract infections (RTIs) in older residents of long-term care facilities (LTCFs). DESIGN: Data from a prospective, randomized, controlled study of the effect of vitamin E supplementation on RTIs conducted from April 1998 through August 2001 were analyzed. SETTING: Thirty-three LTCFs in the greater Boston area. PARTICIPANTS: Six hundred seventeen subjects aged 65 and older residing in LTCFs. MEASUREMENTS: RTIs, categorized as acute bronchitis, pneumonia, common cold, influenza-like illness, pharyngitis, and sinusitis, were studied for appropriateness of antimicrobial use, type of antibiotics used, and factors associated with their use. For cases in which drug treatment was administered, antibiotic use was rated as appropriate (when an effective drug was used), inappropriate (when a more-effective drug was indicated), or unjustified (when use of any antimicrobial was not indicated). RESULTS: Of 752 documented episodes of RTI, overall treatment was appropriate in 79% of episodes, inappropriate in 2%, and unjustified in 19%. For acute bronchitis, treatment was appropriate in 35% and unjustified in 65% of cases. For pneumonia, treatment was appropriate in 87% of episodes. Of the most commonly used antimicrobials, macrolide use was unjustified in 43% of cases. No statistically significant differences in the patterns of antibiotic use were observed when stratified according to age, sex, race, or comorbid conditions, including diabetes mellitus, dementia, and chronic kidney disease. CONCLUSION: Antimicrobials were unjustifiably used for one-fifth of RTIs and more than two-thirds of cases of acute bronchitis, suggesting a need for programs to improve antibiotic prescribing at LTCFs.


Assuntos
Antibacterianos/uso terapêutico , Instituição de Longa Permanência para Idosos/estatística & dados numéricos , Assistência de Longa Duração/estatística & dados numéricos , Casas de Saúde/estatística & dados numéricos , Infecções Respiratórias/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Boston , Método Duplo-Cego , Quimioterapia Combinada , Revisão de Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Masculino , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Infecções Respiratórias/epidemiologia , Vitamina E/uso terapêutico
14.
Nutr Rev ; 68(1): 30-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20041998

RESUMO

Low zinc status may be a risk factor for pneumonia in the elderly. This special article reviews the magnitude of the problem of pneumonia (its prevalence, morbidity, and mortality) in the elderly, pneumonia's etiology, and the dysregulation of the immune system associated with increasing age. In addition, recent evidence from the literature is presented demonstrating that low zinc status (commonly reported in the elderly) impairs immune function, decreases resistance to pathogens, and is associated with increased incidence and duration of pneumonia, increased use and duration of antimicrobial treatment, and increased overall mortality in the elderly. Inadequate stores of zinc might, therefore, be a risk factor for pneumonia in the elderly. Randomized, double-blind, controlled studies are needed to determine the efficacy of zinc supplementation as a potential low-cost intervention to reduce morbidity and mortality due to pneumonia in this vulnerable population.


Assuntos
Estado Nutricional , Pneumonia/etiologia , Zinco/deficiência , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/imunologia , Deficiências Nutricionais/complicações , Deficiências Nutricionais/prevenção & controle , Humanos , Estado Nutricional/imunologia , Pneumonia/epidemiologia , Pneumonia/mortalidade , Prevalência , Fatores de Risco
15.
J Infect Dis ; 197(11): 1499-505, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18471061

RESUMO

BACKGROUND: Tuberculosis (TB) often coincides with nutritional deficiencies. The effects of micronutrient supplementation on TB treatment outcomes, clinical complications, and mortality are uncertain. METHODS: We conducted a randomized, double-blind, placebo-controlled trial of micronutrients (vitamins A, B complex, C, and E, as well as selenium) in Dar es Salaam, Tanzania. We enrolled 471 human immunodeficiency virus (HIV)-infected and 416 HIV-negative adults with pulmonary TB at the time of initiating chemotherapy and monitored them for a median of 43 months. RESULTS: Micronutrients decreased the risk ofTB recurrence by 45% overall (95% confidence interval [CI], 7% to 67%; P = .02) and by 63% in HIV-infected patients (95% CI, 8% to 85%; P = .02). There were no significant effects on mortality overall; however, we noted a marginally significant 64% reduction of deaths in HIV-negative subjects (95% CI, -14% to 88%; P = .08). Supplementation increased CD3+ and CD4+ cell counts and decreased the incidence of extrapulmonary TB and genital ulcers in HIV-negative patients. Micronutrients reduced the incidence of peripheral neuropathy by 57% (95% CI, 41% to 69%; P < .001), irrespective of HIV status. There were no significant effects on weight gain, body composition, anemia, or HIV load. CONCLUSIONS: Micronutrient supplementation could improve the outcome in patients undergoing TB chemotherapy in Tanzania.


Assuntos
Micronutrientes/uso terapêutico , Subpopulações de Linfócitos T/imunologia , Tuberculose Pulmonar/prevenção & controle , Tuberculose Pulmonar/terapia , Adulto , Método Duplo-Cego , Feminino , Infecções por HIV/complicações , Humanos , Incidência , Masculino , Prevenção Secundária , Tanzânia , Resultado do Tratamento , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/mortalidade
16.
Am J Clin Nutr ; 86(4): 1167-73, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17921398

RESUMO

BACKGROUND: Zinc plays an important role in immune function. The association between serum zinc and pneumonia in the elderly has not been studied. OBJECTIVE: The objective was to determine whether serum zinc concentrations in nursing home elderly are associated with the incidence and duration of pneumonia, total and duration of antibiotic use, and pneumonia-associated and all-cause mortality. DESIGN: This observational study was conducted in residents from 33 nursing homes in Boston, MA, who participated in a 1-y randomized, double-blind, and placebo-controlled vitamin E supplementation trial; all were given daily doses of 50% of the recommended dietary allowance of essential vitamins and minerals, including zinc. Participants with baseline (n = 578) or final (n = 420) serum zinc concentrations were categorized as having low (<70 microg/dL) or normal (>or=70 microg/dL) serum zinc concentrations. Outcome measures included the incidence and number of days with pneumonia, number of new antibiotic prescriptions, days of antibiotic use, death due to pneumonia, and all-cause mortality. RESULTS: Compared with subjects with low zinc concentrations, subjects with normal final serum zinc concentrations had a lower incidence of pneumonia, fewer (by almost 50%) new antibiotic prescriptions, a shorter duration of pneumonia, and fewer days of antibiotic use (3.9 d compared with 2.6 d) (P

Assuntos
Instituição de Longa Permanência para Idosos , Casas de Saúde , Pneumonia/sangue , Pneumonia/epidemiologia , Vitamina E/administração & dosagem , Zinco/sangue , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Boston/epidemiologia , Causas de Morte , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Incidência , Masculino , Estado Nutricional , Pneumonia/tratamento farmacológico , Pneumonia/mortalidade , Fatores de Tempo , Vitaminas/administração & dosagem , Zinco/imunologia
17.
J Gerontol A Biol Sci Med Sci ; 60(11): 1469-74, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16339336

RESUMO

BACKGROUND: Concomitant with the substantial growth of the elderly population in the last decade, there has been a steady rise in the number of nursing home residents aged 65 years and older. Well designed, rigorously conducted clinical intervention trials provide an important source of data for evidence-based improvements in the medical care of nursing home residents. The information available on strategies for the recruitment and screening of participants for such studies in long-term care facilities, as well as the financial and time costs for carrying out these investigations, is limited. METHODS: This report describes our experience in recruiting 617 nursing home residents for a multisite, double-blind, randomized, placebo-controlled trial designed to determine the efficacy of a 1-year period of vitamin E supplementation in preventing respiratory tract infections. Comparisons of the projected staffing costs and actual costs incurred are presented, using a retrospective method for the determination of unit costs. RESULTS: Initially, 874 consents were obtained from 2815 potential participants, of which only 617 were enrolled. Each successful enrollment required an average of 15 hours of staff time at a combined personnel and supply cost of $515 per participant and a total study cost of $317,661. Several obstacles were encountered during the recruitment and enrollment process: resistance on the part of family or primary care provider; transfer out of facility; and changes in the medical condition of the patient, including death. DISCUSSION: The results of this report should prove useful to investigators developing budgets for nursing home-based clinical trials by providing a more accurate determination of the personnel needed and the costs associated with recruitment and enrollment of participants.


Assuntos
Ensaios Clínicos como Assunto/economia , Casas de Saúde , Vitamina E/administração & dosagem , Método Duplo-Cego , Humanos , Consentimento Livre e Esclarecido , Placebos
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