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1.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474320

RESUMO

Recent mechanistic studies have indicated that combinations of radiotherapy (RT) plus immunotherapy (via CSF-1R inhibition) can serve as a strategy to overcome RT resistance and improve the survival of glioma mice. Given the high mortality rate for glioma, including low-grade glioma (LGG) patients, it is of critical importance to investigate the mechanism of the combination of RT and immunotherapy and further translate the mechanism from mouse studies to improve survival of RT-treated human glioma patients. Using the RNA-seq data from a glioma mouse study, 874 differentially expressed genes (DEGs) between the group of RT-treated mice at glioma recurrence and the group of mice with combination treatment (RT plus CSF-1R inhibition) were translated to the human genome to identify significant molecular pathways using the KEGG enrichment analysis. The enrichment analysis yields statistically significant signaling pathways, including the phosphoinositide 3-kinase (PI3K)/AKT pathway, Hippo pathway, and Notch pathway. Within each pathway, a candidate gene set was selected by Cox regression models as genetic biomarkers for resistance to RT and response to the combination of RT plus immunotherapies. Each Cox model is trained using a cohort of 295 RT-treated LGG patients from The Cancer Genome Atlas (TCGA) database and validated using a cohort of 127 RT-treated LGG patients from the Chinese Glioma Genome Atlas (CGGA) database. A four-DEG signature (ITGB8, COL9A3, TGFB2, JAG1) was identified from the significant genes within the three pathways and yielded the area under time-dependent ROC curve AUC = 0.86 for 5-year survival in the validation set, which indicates that the selected DEGs have strong prognostic value and are potential intervention targets for combination therapies. These findings may facilitate future trial designs for developing combination therapies for glioma patients.


Assuntos
Neoplasias Encefálicas , Glioma , Radioterapia (Especialidade) , Humanos , Animais , Camundongos , Fosfatidilinositol 3-Quinases , Fosfatidilinositol 3-Quinase , Imunoterapia
2.
Adv Nutr ; 14(5): 948-958, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37270030

RESUMO

Achieving optimal health is an aspirational goal for the population, yet the definition of health remains unclear. The role of nutrition in health has evolved beyond correcting malnutrition and specific deficiencies and has begun to focus more on achieving and maintaining 'optimal' health through nutrition. As such, the Council for Responsible Nutrition held its October 2022 Science in Session conference to advance this concept. Here, we summarize and discuss the findings of their Optimizing Health through Nutrition - Opportunities and Challenges workshop, including several gaps that need to be addressed to advance progress in the field. Defining and evaluating various indices of optimal health will require overcoming these key gaps. For example, there is a strong need to develop better biomarkers of nutrient status, including more accurate markers of food intake, as well as biomarkers of optimal health that account for maintaining resilience-the ability to recover from or respond to stressors without loss to physical and cognitive performance. In addition, there is a need to identify factors that drive individualized responses to nutrition, including genotype, metabotypes, and the gut microbiome, and to realize the opportunity of precision nutrition for optimal health. This review outlines hallmarks of resilience, provides current examples of nutritional factors to optimize cognitive and performance resilience, and gives an overview of various genetic, metabolic, and microbiome determinants of individualized responses.


Assuntos
Microbioma Gastrointestinal , Ciências da Nutrição , Humanos , Estado Nutricional , Biomarcadores
3.
J Diet Suppl ; 19(3): 336-365, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33594938

RESUMO

COVID-19 (COronaVIrus Disease of 2019), the disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), represents an ongoing global health challenge and the deadliest epidemic coronavirus outbreak to date. Early sequencing of the viral genome and knowledge from past coronavirus outbreaks (SARS-CoV-1 and Middle East Respiratory Syndrome, MERS) has led to rapid advances in knowledge of how the virus spreads and infects human hosts. Unfortunately, advancing knowledge has not yet produced a treatment that substantially lowers morbidity or mortality and only recently resulted in the development of a vaccine that prevents severe disease. Mounting evidence supports the notion that dietary supplementation of key essential nutrients may contribute to the body's defenses against infection as well as bolster the body's responses to infection. Evidence supporting the potential beneficial roles of vitamin C, vitamin D, zinc, and B3 vitamins is reviewed here, revealing a combination of basic research elucidating underlying mechanisms of action, preclinical studies and human intervention studies has led to the proliferation of registered clinical trials on COVID-19. Overall, the data suggest this collection of nutrients has a promising impact on reducing the risk and/or severity of COVID-19, although firm conclusions await the results of these trials.


Assuntos
COVID-19 , COVID-19/prevenção & controle , Suplementos Nutricionais , Humanos , SARS-CoV-2 , Vitamina D , Vitaminas/uso terapêutico
4.
Nutr Rev ; 78(6): 451-458, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31769838

RESUMO

Many terms for plant-derived food components are commonly used in the literature, but there is a notable lack of standardization and definition of nomenclature. The use of terms is often field-specific, leading to misunderstanding and problems with literature searches and systematic reviews, and results in isolated and divided research; this impacts not only publication quality but also innovation, regulatory compliance, and enforcement. To begin to address this issue, this narrative review describes the current use and definition of terms. The terms are either chemical and/or origin-based, such as phytochemical (chemicals from plants), or function-based, such as phytonutrient, bioactive, or nutraceutical. The ultimate goal is to establish a common harmonized, evidence-based understanding for when to use each term, thereby providing clarity and a specific scientific basis for such nomenclature. Neither the quality nor the quantity of evidence needed to allow the use of functional terms such as phytonutrient or nutraceutical is specifically discussed here; rather, it is simply noted that evidence is needed to apply these terms. The next step would be to define the evidence necessary for a compound to have a functional descriptor. The aim in this article is to establish scientific criteria for definitions that could be applied to clearly define and differentiate commonly used terms and thus ensure their consistent application in the scientific literature.


Assuntos
Compostos Fitoquímicos , Preparações de Plantas , Terminologia como Assunto , Pesquisa Biomédica , Humanos , Ciências da Nutrição
5.
Regul Toxicol Pharmacol ; 95: 412-433, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29580974

RESUMO

A systematic review of published toxicology and human intervention studies was performed to characterize potential hazards associated with consumption of green tea and its preparations. A review of toxicological evidence from laboratory studies revealed the liver as the target organ and hepatotoxicity as the critical effect, which was strongly associated with certain dosing conditions (e.g. bolus dose via gavage, fasting), and positively correlated with total catechin and epigallocatechingallate (EGCG) content. A review of adverse event (AE) data from 159 human intervention studies yielded findings consistent with toxicological evidence in that a limited range of concentrated, catechin-rich green tea preparations resulted in hepatic AEs in a dose-dependent manner when ingested in large bolus doses, but not when consumed as brewed tea or extracts in beverages or as part of food. Toxico- and pharmacokinetic evidence further suggests internal dose of catechins is a key determinant in the occurrence and severity of hepatotoxicity. A safe intake level of 338 mg EGCG/day for adults was derived from toxicological and human safety data for tea preparations ingested as a solid bolus dose. An Observed Safe Level (OSL) of 704 mg EGCG/day might be considered for tea preparations in beverage form based on human AE data.


Assuntos
Camellia sinensis , Extratos Vegetais/toxicidade , Chá/toxicidade , Adulto , Animais , Ingestão de Alimentos , Humanos
6.
Regul Toxicol Pharmacol ; 84: 94-101, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28110066

RESUMO

There is increasing interest by consumers, researchers, and regulators into the roles that certain bioactive compounds, derived from plants and other natural sources, can play in health maintenance and promotion, and even prolonging a productive quality of life. Research has rapidly emerged suggesting that a wide range of compounds and mixtures in and from plants (such as fruits and vegetables, tea and cocoa) and animals (such as fish and probiotics) may exert substantial health benefits. There is interest in exploring the possibility of establishing recommended intakes or dietary guidance for certain bioactive substances to help educate consumers. A key aspect of establishing dietary guidance is the assessment of safety/toxicity of these substances. Toxicologists need to be involved in both the development of the safety framework and in the evaluation of the science to establish maximum intake/upper limits.


Assuntos
Catequina/análogos & derivados , Qualidade de Produtos para o Consumidor , Suplementos Nutricionais/efeitos adversos , Inocuidade dos Alimentos , Luteína/efeitos adversos , Preparações de Plantas/efeitos adversos , Testes de Toxicidade/métodos , Toxicologia/métodos , Animais , Catequina/administração & dosagem , Catequina/efeitos adversos , Qualidade de Produtos para o Consumidor/normas , Técnicas de Apoio para a Decisão , Relação Dose-Resposta a Droga , Guias como Assunto , Humanos , Luteína/administração & dosagem , Nível de Efeito Adverso não Observado , Preparações de Plantas/administração & dosagem , Recomendações Nutricionais , Medição de Risco , Testes de Toxicidade/normas , Toxicologia/normas
7.
Adv Nutr ; 6(1): 1-4, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25593139

RESUMO

In the United States, dietary reference intakes describe the relations between nutrient intakes and indicators of adequacy, prevention of disease, and avoidance of excessive intakes among healthy populations for essential nutrients but not dietary bioactive components (DBCs), whose absence from the diet is presumably not deleterious to health (i.e., does not cause a deficiency syndrome). An appropriate framework is needed for establishing recommended intakes for which public health messages and food labeling for DBCs can be derived, because their putative health benefits may not be readily defined in the context of nutritional essentiality. In addition, a myriad of factors make determining their intake and status and investigating their discrete contributions to health particularly challenging. Therefore, the ASN Dietary Bioactive Components Research Interest Section felt it worthwhile to convene a special "hot topic" session at the 2014 Experimental Biology meeting to discuss this issue and serve as a call for future scientific dialogue on establishing a framework for recommended intakes of DBCs. This session summary captures the discussions and presentations that transpired during this session.


Assuntos
Dieta , Flavonoides/administração & dosagem , Luteína/administração & dosagem , Extratos Vegetais/administração & dosagem , Recomendações Nutricionais , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Frutas/química , Humanos , Luteína/farmacologia , Luteína/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Verduras/química
8.
J Diet Suppl ; 10(2): 85-92, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23679573

RESUMO

This special article seeks to provide balance and clarity to the confusion brought about by the conclusions resulting from a recent study published in Archives of Internal Medicine by Mursu et al. (2011). An examination of three key limitations of the study provides context to why additional research is needed: (a) Nonusers were poorly defined; (b) supplement users were healthier than nonusers; and (c) the number of supplement users increased throughout the study. Although the literature is limited, other similar observational studies have also shown positive effects on the risk mortality for both multivitamins and single-nutrient supplements. Observational trials are an essential component of evidence-based nutrition but do not offer certainty because other data, such as the one generated from randomized controlled trials, are equally important in regard to the totality of evidence. The Senior Scientific Advisory Committee for the Council for Responsible Nutrition, an industry trade group, feels that the conclusions of the study by Mursu et al. (2011) are overstated and suggests that researchers analyze cohort(s) designed to specifically examine vitamin and mineral supplements free of confounding from factors, such as hormone replacement therapy, to better assess their benefits to the general population.


Assuntos
Doença Crônica/prevenção & controle , Suplementos Nutricionais , Mortalidade/tendências , Saúde da Mulher , Feminino , Humanos , Masculino
9.
Eur J Nutr ; 52 Suppl 1: 1-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23455383

RESUMO

Nutrients can be classified as either "essential" or "non-essential," the latter are also termed bioactive substances. Whereas the absence of essential nutrients from the diet results in overt deficiency often times with moderate to severe physiological decrements, the absence of bioactive substances from the diet results in suboptimal health. Nutrient reference values are set by Codex Alimentarius and regulatory bodies in many countries, mostly for essential nutrients with recommended daily intakes. The IOM in the United States has defined a set of four DRIs that, when data are appropriate, include an EAR, a RDA that is derived from the EAR, an AI for nutrients without appropriate data to identify an EAR, and an UL. From the RDA, the United States derives a labeling value called the DV, which applies to older children and most adults. In Codex, the equivalents of the DVs are the NRVs to be used in calculating percentage values on food labels. Nothing in the IOM documents specifies that labeling values can be set only for what have been defined to date as essential nutrients. Indeed, the US Food and Drug Administration sets a labeling value for dietary fiber based on the IOM AI for this ingredient. This conference explores the definitions, concepts, and data on two of the best examples of bioactive substances that, perhaps, should have NRVs: lutein and zeaxanthin, and n-3 long-chain polyunsaturated fatty acids.


Assuntos
Dieta , Ácidos Graxos Ômega-3 , Luteína , Política Nutricional , Xantofilas , Encéfalo/fisiologia , Carotenoides , Criança , Alimentos , Rotulagem de Alimentos , Promoção da Saúde , Humanos , Degeneração Macular/prevenção & controle , Necessidades Nutricionais , Valores de Referência , Estados Unidos , Visão Ocular , Zeaxantinas
11.
Nutr J ; 10: 20, 2011 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-21371318

RESUMO

BACKGROUND: Dietary supplements are regularly used by a majority of the American population, and usage by health professionals is also common. There is considerable interest in usage patterns within the population and in the reasons for using dietary supplements. The "Life...supplemented" Healthcare Professionals 2008 Impact Study (HCP Impact Study) surveyed usage of dietary supplements by physicians in three specialties: cardiology, dermatology, and orthopedics. METHODS: The HCP Impact Study was conducted online by Ipsos Public Affairs for the Council for Responsible Nutrition (CRN), a trade association of the dietary supplement industry. Respondents were 900 physicians, including 300 each from three specialties--cardiology, dermatology, and orthopedics. RESULTS: Fifty-seven percent of cardiologists said they use dietary supplements at least occasionally, as did 75% of dermatologists and 73% of orthopedists. The product most commonly reported to be used was a multivitamin, but over 25% in each specialty said they used omega-3 fatty acids and over 20% said they used some botanical supplements. Regular dietary supplement use was reported by 37% of cardiologists, 59% of dermatologists, and 50% of orthopedists. Seventy-two percent of cardiologists, 66% of dermatologists, and 91% of orthopedists reported recommending dietary supplements to their patients. The primary reason given for recommending dietary supplements to patients was for heart health or lowering cholesterol for the cardiologists; benefits for skin, hair and nails for the dermatologists; and bone and joint health for the orthopedists. CONCLUSIONS: Reported dietary supplement use was relatively common in this sample of physicians, and when they recommended dietary supplements to patients, they tended to do so for reasons related to their specialty.


Assuntos
Cardiologia , Dermatologia , Suplementos Nutricionais/estatística & dados numéricos , Ortopedia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vitaminas/administração & dosagem
12.
Amino Acids ; 40(5): 1369-83, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21424716

RESUMO

Creatine has become one of the most popular dietary supplements in the sports nutrition market. The form of creatine that has been most extensively studied and commonly used in dietary supplements is creatine monohydrate (CM). Studies have consistently indicated that CM supplementation increases muscle creatine and phosphocreatine concentrations by approximately 15-40%, enhances anaerobic exercise capacity, and increases training volume leading to greater gains in strength, power, and muscle mass. A number of potential therapeutic benefits have also been suggested in various clinical populations. Studies have indicated that CM is not degraded during normal digestion and that nearly 99% of orally ingested CM is either taken up by muscle or excreted in urine. Further, no medically significant side effects have been reported in literature. Nevertheless, supplement manufacturers have continually introduced newer forms of creatine into the marketplace. These newer forms have been purported to have better physical and chemical properties, bioavailability, efficacy, and/or safety profiles than CM. However, there is little to no evidence that any of the newer forms of creatine are more effective and/or safer than CM whether ingested alone and/or in combination with other nutrients. In addition, whereas the safety, efficacy, and regulatory status of CM is clearly defined in almost all global markets; the safety, efficacy, and regulatory status of other forms of creatine present in today's marketplace as a dietary or food supplement is less clear.


Assuntos
Creatina , Creatina/administração & dosagem , Creatina/efeitos adversos , Creatina/metabolismo , Humanos
13.
Nutr J ; 8: 29, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19570197

RESUMO

BACKGROUND: Numerous surveys show that dietary supplements are used by a large proportion of the general public, but there have been relatively few surveys on the prevalence of dietary supplement use among health professionals, including physicians and nurses. Even less information is available regarding the extent to which physicians and nurses recommend dietary supplements to their patients. METHODS: An online survey was administered in October 2007 to 900 physicians and 277 nurses by Ipsos Public Affairs for the Council for Responsible Nutrition (CRN), a trade association representing the dietary supplement industry. The health professionals were asked whether they used dietary supplements and their reasons for doing so, and whether they recommend dietary supplements to their patients. RESULTS: The "Life...supplemented" Healthcare Professionals Impact Study (HCP Impact Study) found that 72% of physicians and 89% of nurses in this sample used dietary supplements regularly, occasionally, or seasonally. Regular use of dietary supplements was reported by 51% of physicians and 59% of nurses. The most common reason given for using dietary supplements was for overall health and wellness (40% of physicians and 48% of nurses), but more than two-thirds cited more than one reason for using the products. When asked whether they "ever recommend dietary supplements" to their patients, 79% of physicians and 82% of nurses said they did. CONCLUSION: Physicians and nurses are as likely as members of the general public to use dietary supplements, as shown by comparing the results of this survey with data from national health and nutrition surveys. Also, most physicians and nurses recommend supplements to their patients, whether or not the clinicians use dietary supplements themselves.


Assuntos
Suplementos Nutricionais/estatística & dados numéricos , Enfermeiras e Enfermeiros , Inquéritos Nutricionais , Médicos , Adulto , Atitude do Pessoal de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica , Estados Unidos
14.
J Cell Physiol ; 219(1): 132-42, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19097033

RESUMO

We examined the role of the extracellular signal regulated kinases (ERK) in 1,25-dihydroxyvitamin D (1,25(OH)(2)D(3))-induced gene expression in the differentiated Caco-2 cells. 1,25(OH)(2)D(3)-regulated expression of the 25-hydroxyvitamin D, 24-hydroxylase (CYP24) gene (both natural gene and promoter construct) was strongly modulated by altering ERK activity (i.e., reduced by MEK inhibitors and dominant negative (dn) ERK1 and ERK2, activated by epidermal growth factor) but ERK inhibition had no effect on 1,25(OH)(2)D(3)-regulated expression of the transient receptor potential cation channel, subfamily V, member 6 (TRPV6). ERK5-mediated phosphorylation of the transcription factor Ets-1 enhanced 1,25(OH)(2)D(3)-mediated CYP24 gene transcription in proliferating but not differentiated Caco-2 cells due to reduced levels of ERK5 and Ets-1 (total and phosphoprotein levels) in differentiated cells. MEK inhibition reduced 1,25(OH)(2)D(3)-induced 3X-VDRE promoter activity but had no impact on the association of vitamin D receptor (VDR) with chromatin suggesting a role for co-activator recruitment in ERK-modulation of vitamin D-regulated CYP24 gene activation. Chromatin immunoprecipitation assays revealed that the ERK1/2 target, mediator 1 (MED1), is recruited to the CYP24, but not the TRPV6, promoter following 1,25(OH)(2)D(3) treatment. MED1 phosphorylation was sensitive to activators and inhibitors of the ERK1/2 signaling and MED1 siRNA reduced 1,25(OH)(2)D(3)-regulated human CYP24 promoter activity. This suggests ERK1/2 signaling enhances 1,25(OH)(2)D(3) effects on the CYP24 promoter by MED1-mediated events. Our data show that there are both promoter-specific and cell stage-specific roles for the ERK signaling pathway on 1,25(OH)(2)D(3)-mediated gene induction in enterocyte-like Caco-2 cells.


Assuntos
Calcitriol/metabolismo , Regulação Enzimológica da Expressão Gênica , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Esteroide Hidroxilases/genética , Esteroide Hidroxilases/metabolismo , Células CACO-2/fisiologia , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Inibidores Enzimáticos/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Humanos , Imidazóis/metabolismo , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 2/antagonistas & inibidores , MAP Quinase Quinase 2/genética , MAP Quinase Quinase 2/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/genética , Regiões Promotoras Genéticas , Proteína Proto-Oncogênica c-ets-1/genética , Proteína Proto-Oncogênica c-ets-1/metabolismo , Interferência de RNA , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Receptor X Retinoide alfa/genética , Receptor X Retinoide alfa/metabolismo , Esteroide Hidroxilases/antagonistas & inibidores , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Técnicas do Sistema de Duplo-Híbrido , Vitamina D3 24-Hidroxilase , Vitaminas/metabolismo
15.
J Nutr ; 138(10): 1992S-1995S, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18806113

RESUMO

The original tolerable upper intake level (UL) method greatly improved the application of risk assessment to the evaluation of nutrient safety for humans, but a UL is only set where the data establish a hazard resulting from high intakes. Absence of a UL for those nutrients with no established hazard has been misinterpreted by regulators and resulted in overly restrictive policies. To prevent such misinterpretation, the observed safe level (OSL) was developed and defined as "the highest intake with convincing evidence of safety, even if there are no established adverse effects at any level." More recently, a FAO/WHO report gave a similar definition for the highest observed intake (HOI). Another disadvantage of the UL method is the application of arbitrary uncertainty factors (UF). An alternative to the traditional adjustment for uncertainty involves arranging the data in decreasing order of daily intake, followed by evaluation of each trial for quantity and quality of data. Studies are selected downward until no adverse effects are observed in a trial of sufficient quality to justify no further correction for uncertainty (i.e. selection of data that qualify for UF = 1). Thus, the no observed adverse effect level or OSL selected requires no further adjustment for uncertainty. For supplemental intakes of some vitamins, many bioactive substances, and most amino acids, no adverse effects that are clearly related to high intakes have been established, but where the dataset is sufficiently robust, application of the OSL-HOI technique can provide risk assessment values.


Assuntos
Ingestão de Energia , Alimentos/normas , Suplementos Nutricionais , Guias como Assunto , Humanos , National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division , Necessidades Nutricionais , Medição de Risco/métodos , Segurança , Incerteza , Estados Unidos
16.
Regul Toxicol Pharmacol ; 50(3): 376-99, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18325648

RESUMO

Taurine, glutamine and arginine are examples of amino acids which have become increasingly popular as ingredients in dietary supplements and functional foods and beverages. Animal and human clinical research suggests that oral supplementation of these amino acids provides additional health and/or performance benefits beyond those observed from normal intake of dietary protein. The increased consumer awareness and use of these amino acids as ingredients in dietary supplements and functional foods warrant a comprehensive review of their safety through quantitative risk assessment, and identification of a potential safe upper level of intake. The absence of a systematic pattern of adverse effects in humans in response to orally administered taurine (Tau), l-glutamine (Gln) and l-arginine (Arg) precluded the selection of a no observed adverse effect level (NOAEL) or lowest observed adverse effect level (LOAEL). Therefore, by definition, the usual approach to risk assessment for identification of a tolerable upper level of intake (UL) could not be used. Instead, the newer method described as the Observed Safe Level (OSL) or Highest Observed Intake (HOI) was utilized. The OSL risk assessments indicate that based on the available published human clinical trial data, the evidence for the absence of adverse effects is strong for Tau at supplemental intakes up to 3 g/d, Gln at intakes up to 14 g/d and Arg at intakes up to 20 g/d, and these levels are identified as the respective OSLs for normal healthy adults. Although much higher levels of each of these amino acids have been tested without adverse effects and may be safe, the data for intakes above these levels are not sufficient for a confident conclusion of long-term safety, and therefore these values are not selected as the OSLs.


Assuntos
Arginina/toxicidade , Glutamina/toxicidade , Taurina/toxicidade , Adulto , Animais , Bebidas/análise , Criança , Interpretação Estatística de Dados , Suplementos Nutricionais/toxicidade , Análise de Alimentos , Humanos , Nível de Efeito Adverso não Observado , Medição de Risco
17.
Am J Clin Nutr ; 85(1): 6-18, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17209171

RESUMO

The objective of this review was to apply the risk assessment methodology used by the Food and Nutrition Board (FNB) to derive a revised safe Tolerable Upper Intake Level (UL) for vitamin D. New data continue to emerge regarding the health benefits of vitamin D beyond its role in bone. The intakes associated with those benefits suggest a need for levels of supplementation, food fortification, or both that are higher than current levels. A prevailing concern exists, however, regarding the potential for toxicity related to excessive vitamin D intakes. The UL established by the FNB for vitamin D (50 microg, or 2000 IU) is not based on current evidence and is viewed by many as being too restrictive, thus curtailing research, commercial development, and optimization of nutritional policy. Human clinical trial data published subsequent to the establishment of the FNB vitamin D UL published in 1997 support a significantly higher UL. We present a risk assessment based on relevant, well-designed human clinical trials of vitamin D. Collectively, the absence of toxicity in trials conducted in healthy adults that used vitamin D dose > or = 250 microg/d (10,000 IU vitamin D3) supports the confident selection of this value as the UL.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Osso e Ossos/metabolismo , Política Nutricional , Deficiência de Vitamina D/prevenção & controle , Vitamina D , Conservadores da Densidade Óssea/efeitos adversos , Suplementos Nutricionais , Medicina Baseada em Evidências , Feminino , Alimentos Fortificados , Humanos , Hipercalcemia/induzido quimicamente , Hipercalcemia/prevenção & controle , Masculino , Dose Máxima Tolerável , Nível de Efeito Adverso não Observado , Necessidades Nutricionais , Medição de Risco , Estados Unidos , Vitamina D/administração & dosagem , Vitamina D/efeitos adversos , Deficiência de Vitamina D/complicações , Vitaminas/administração & dosagem , Vitaminas/efeitos adversos
18.
Regul Toxicol Pharmacol ; 47(1): 78-83, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16942821

RESUMO

Glucosamine and chondroitin sulfate are two popular dietary ingredients present in dietary supplements intended to support joint health. A large body of human and animal research suggests that oral intakes of these ingredients, either alone or in combination, reduces joint pain and improves mobility in persons with osteoarthritis. The increased awareness and use of these ingredients in dietary supplements warrant a comprehensive review of their safety. Systematic evaluation of the research designs and data do not provide a basis for risk assessment and the usual safe upper level of intake (UL) derived from it unless the newer methods described as the observed safe level (OSL) or highest observed intake (HOI) are utilized. The OSL risk assessment method indicates that the evidence strongly supports safety at intakes up to 2000 mg/d for glucosamine, and 1200 mg/d for chondroitin sulfate, and these levels are identified as the respective OSL. These values represent the highest levels tested in human clinical trials. The complete absence of adverse effects at these levels supports a confident conclusion of their long-term safety.


Assuntos
Sulfatos de Condroitina/toxicidade , Suplementos Nutricionais/toxicidade , Glucosamina/toxicidade , Administração Oral , Animais , Células Cultivadas , Humanos , Nível de Efeito Adverso não Observado , Medição de Risco
19.
Regul Toxicol Pharmacol ; 46(1): 23-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16901595

RESUMO

Carnitine is a conditionally essential amino acid-like compound involved in the transport of long-chain fatty acids into the mitochondria during the beta-oxidation process. Carnitine has become an increasingly popular ingredient in dietary supplements, especially weight loss and some sports nutrition products. A number of clinical trials have been conducted examining the effect of carnitine supplementation on weight loss and energy balance. Regarding safety, systematic evaluation of the research designs and data do not provide a basis for risk assessment and the usual safe upper level of intake (UL) derived from it unless the newer methods described as the observed safe level (OSL) or highest observed intake (HOI) are utilized. The OSL risk assessment method indicates that the evidence of safety is strong at intakes up to 2000mg/day l-carnitine equivalents for chronic supplementation, and this level is identified as the OSL. Although much higher levels have been tested without adverse effects and may be safe, the data for intakes above 2000mg/day are not sufficient for a confident conclusion of long-term safety.


Assuntos
Carnitina/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Relação Dose-Resposta a Droga , Humanos , Medição de Risco , Testes de Toxicidade/métodos
20.
Regul Toxicol Pharmacol ; 45(3): 242-51, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16814437

RESUMO

Creatine monohydrate (creatine) has become an increasingly popular ingredient in dietary supplements, especially sports nutrition products. A large body of human and animal research suggests that creatine does have a consistent ergogenic effect, particularly with exercises or activities requiring high intensity short bursts of energy. Human data are primarily derived from three types of studies: acute studies, involving high doses (20 g/d) with short duration (< or = 1 week), chronic studies involving lower doses (3-5 g/d) and longer duration (1 year), or a combination of both. Systematic evaluation of the research designs and data do not provide a basis for risk assessment and the usual safe Upper Level of Intake (UL) derived from it unless the newer methods described as the Observed Safe Level (OSL) or Highest Observed Intake (HOI) are utilized. The OSL risk assessment method indicates that the evidence of safety is strong at intakes up to 5 g/d for chronic supplementation, and this level is identified as the OSL. Although much higher levels have been tested under acute conditions without adverse effects and may be safe, the data for intakes above 5 g/d are not sufficient for a confident conclusion of long-term safety.


Assuntos
Creatina/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Animais , Creatina/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Medição de Risco
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