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1.
Mult Scler ; 25(9): 1326-1328, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30358476

RESUMO

Knowledge about complications of chronic ultra-high dose vitamin D supplementation is limited. We report a patient with primary progressive multiple sclerosis (MS) who presented with generalized weakness caused by hypercalcemia after uncontrolled intake of more than 50,000 IU of cholecalciferol per day over several months. Various treatment strategies were required to achieve normocalcemia. However, renal function improved only partly and further progression of MS was observed. We conclude that patients need to be informed about the risks of uncontrolled vitamin D intake and neurologists need to be alert of biochemical alterations and symptoms of vitamin D toxicity.


Assuntos
Colecalciferol/toxicidade , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Hipercalcemia/induzido quimicamente , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Vitaminas/toxicidade , Colecalciferol/administração & dosagem , Humanos , Hipercalcemia/complicações , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/etiologia , Vitaminas/administração & dosagem
2.
Arch Toxicol ; 87(12): 2083-103, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24173581

RESUMO

The high worldwide prevalence of vitamin D deficiency is largely the result of low sunlight exposure with subsequently limited cutaneous vitamin D production. Classic manifestations of vitamin D deficiency are linked to disturbances in bone and mineral metabolism, but the identification of the vitamin D receptor in almost every human cell suggests a broader role of vitamin D for overall and cardiovascular health. The various cardiovascular protective actions of vitamin D such as anti-diabetic and anti-hypertensive effects including renin suppression as well as protection against atherosclerosis and heart diseases are well defined in previous experimental studies. In line with this, large epidemiological studies have highlighted vitamin D deficiency as a marker of cardiovascular risk. However, randomized controlled trials (RCTs) on vitamin D have largely failed to show its beneficial effects on cardiovascular diseases and its conventional risk factors. While most prior vitamin D RCTs were not designed to assess cardiovascular outcomes, some large RCTs have been initiated to evaluate the efficacy of vitamin D supplementation on cardiovascular events in the general population. When considering the history of previous disappointing vitamin RCTs in general populations, more emphasis should be placed on RCTs among severely vitamin D-deficient populations who would most likely benefit from vitamin D treatment. At present, vitamin D deficiency can only be considered a cardiovascular risk marker, as vitamin D supplementation with doses recommended for osteoporosis treatment is neither proven to be beneficial nor harmful in cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Deficiência de Vitamina D/fisiopatologia , Vitamina D/fisiologia , Animais , Aterosclerose/epidemiologia , Aterosclerose/genética , Aterosclerose/metabolismo , Cálcio/metabolismo , Doenças Cardiovasculares/epidemiologia , Transtornos Cerebrovasculares/epidemiologia , Transtornos Cerebrovasculares/genética , Transtornos Cerebrovasculares/metabolismo , Suplementos Nutricionais , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Humanos , Prevalência , Fatores de Risco , Luz Solar , Vitamina D/genética , Vitamina D/metabolismo , Vitamina D/toxicidade , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/genética , Vitaminas/metabolismo , Vitaminas/toxicidade
3.
Plant Biotechnol J ; 10(9): 1026-34, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22928600

RESUMO

Multivitamin corn is a novel genetically engineered variety that simultaneously produces high levels of ß-carotene, ascorbate and folate, and therefore has the potential to address simultaneously multiple micronutrient deficiencies caused by the lack of vitamins A, B9 and C in developing country populations. As part of the development process for genetically engineered crops and following European Food Safety Authority (EFSA) recommendations, multivitamin corn must be tested in whole food/feed sub-chronic animal feeding studies to ensure there are no adverse effects, and potential allergens must be identified. We carried out a 28-day toxicity assessment in mice, which showed no short-term sub-acute evidence of diet-related adverse health effects and no difference in clinical markers (food consumption, body weight, organ/tissue weight, haematological and biochemical blood parameters and histopathology) compared to mice fed on a control diet. A subsequent 90-day sub-chronic feeding study again showed no indications of toxicity compared to mice fed on control diets. Our data confirm that diets enriched with multivitamin corn have no adverse effects on mice, do not induce any clinical signs of toxicity and do not contain known allergens.


Assuntos
Plantas Geneticamente Modificadas/toxicidade , Vitaminas/administração & dosagem , Zea mays/toxicidade , Animais , Feminino , Masculino , Camundongos , Testes de Toxicidade Subaguda , Testes de Toxicidade Subcrônica , Vitaminas/toxicidade
4.
Birth Defects Res ; 114(3-4): 136-144, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34967143

RESUMO

PURPOSE: To investigate the factors that influence the occurrence of anorectal malformations (ARMs). METHODS: From December 2018 to December 2019, 136 children treated for ARMs at the Children's Hospital of Chongqing Medical University were included in the case group. The control group consisted of children with intussusception or perianal abscesses. A uniform questionnaire was filled by the parents of the enrolled children. RESULTS: The birth weight of the cases was significantly lower than that of the controls (p < .01), and children with ARMs were more likely to be complicated with single umbilical artery (SUA) (p < .001). Maternal upper respiratory tract infection (adjusted odds ratio [ORadj ], 2.44; 95% confidence interval [CI], 1.29-4.63) and urogenital infection (ORadj , 2.67; 95% CI 1.11-6.38) during the first trimester of pregnancy, anemia during pregnancy (ORadj , 5.69; 95% CI, 1.01-32.07), and exposure to hazardous substances 6 months before pregnancy and during the first trimester of pregnancy (ORadj , 13.82; 95% CI, 3.86-49.35) are associated with increased risk of ARMs. Folic acid supplements (ORadj , 0.31; 95% CI, 0.14-0.65) and multivitamin (ORadj , 0.34; 95% CI, 0.15-0.79) had a protective effect on ARMs. Paternal drug use (ORadj , 9.17; 95% CI, 2.19-38.49) 6 months before their wives' conception increased the risk of ARMs. CONCLUSION: Maternal infection, anemia during pregnancy, and maternal hazardous substances exposure are possible risk factors for ARMs. Folic acid supplements and multivitamin can reduce the occurrence of ARMs. Meanwhile, paternal drug use may also be a risk factor for ARMs.


Assuntos
Malformações Anorretais , Malformações Anorretais/complicações , Malformações Anorretais/epidemiologia , Criança , Feminino , Ácido Fólico/uso terapêutico , Substâncias Perigosas , Humanos , Gravidez , Fatores de Risco , Vitaminas/toxicidade
5.
Food Chem Toxicol ; 169: 113445, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36183923

RESUMO

Dietary supplements (DS) constitute a widely used group of products comprising vitamin, mineral, and botanical extract formulations. DS of botanical or herbal origins (HDS) comprise nearly 30% of all DS and are presented on the market either as single plant extracts or multi-extract-containing products. Despite generally safe toxicological profiles of most products currently present on the market, rising cases of liver injury caused by HDS - mostly by multi-ingredient and adulterated products - are of particular concern. Here we discuss the most prominent historical cases of HDS-induced hepatotoxicty - from Ephedra to Hydroxycut and OxyELITE Pro-NF, as well as products with suspected hepatotoxicity that are either currently on or are entering the market. We further provide discussion on overcoming the existing challenges with HDS-linked hepatotoxicity by introduction of advanced in silico, in vitro, in vivo, and microphysiological system approaches to address the matter of safety of those products before they reach the market.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Suplementos Nutricionais , Extratos Vegetais , Humanos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Suplementos Nutricionais/toxicidade , Extratos Vegetais/toxicidade , Vitaminas/toxicidade , Preparações de Plantas
6.
Alcohol Clin Exp Res ; 35(9): 1644-61, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21554333

RESUMO

BACKGROUND: Microphthalmia (reduced eye size), generally accompanied by vision defects, is a hallmark of fetal alcohol spectrum disorder (FASD) in humans. In zebrafish, embryonic ethanol exposure over the time of retinal neurogenesis also results in microphthalmia. This microphthalmia is in part the consequence of reduced retinal cell differentiation, including photoreceptors. Here we pursue 2 signaling pathways implicated in other aspects of FASD pathogenesis: retinoic acid (RA) and Sonic hedgehog (Shh). METHODS: We evaluated markers for RA and Shh signaling within the eyes of embryos treated with ethanol during the period of retinal neurogenesis. We also performed rescue experiments using administration of exogenous RA and microinjection of cholesterol, which augments Shh signaling. RESULTS: Using sequential or co-treatments, RA did not rescue ethanol-induced microphthalmia at any concentration tested. In addition, RA itself caused microphthalmia, although the underlying mechanisms were distinct from those of ethanol. Interestingly, RA treatment appeared to recover photoreceptor differentiation in a concentration-dependent manner. This may be an independent effect of exogenous RA, as ethanol treatment alone did not alter RA signaling in the eye. Cholesterol injection also did not rescue ethanol-induced microphthalmia at any concentration tested, and ethanol treatments did not alter expression of shh, or of ptc-2, which is normally regulated by Shh signaling. CONCLUSIONS: Together these findings indicate that, during the time of retinal neurogenesis, effects of ethanol on eye development are likely independent of the RA and Shh signaling pathways. These studies suggest that FASD intervention strategies based upon augmentation of RA or Shh signaling may not prevent ethanol-induced microphthalmia.


Assuntos
Depressores do Sistema Nervoso Central/toxicidade , Etanol/toxicidade , Proteínas Hedgehog/metabolismo , Microftalmia/induzido quimicamente , Neurogênese , Retina/embriologia , Tretinoína/metabolismo , Anormalidades Induzidas por Medicamentos/metabolismo , Anormalidades Induzidas por Medicamentos/patologia , Laranja de Acridina/metabolismo , Animais , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Feminino , Microftalmia/metabolismo , Microftalmia/patologia , Retina/metabolismo , Retina/patologia , Transdução de Sinais/efeitos dos fármacos , Transgenes , Tretinoína/farmacologia , Tretinoína/toxicidade , Vitaminas/metabolismo , Vitaminas/farmacologia , Vitaminas/toxicidade , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
7.
J Fam Pract ; 70(8): 386-398, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34818175

RESUMO

This review, with handy tables, summarizes which vitamins offer proven benefits-and which don't.


Assuntos
Suplementos Nutricionais/normas , Vitaminas/metabolismo , Vitaminas/farmacologia , Humanos , Vitaminas/toxicidade
8.
Plant Cell Physiol ; 51(1): 9-20, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19919949

RESUMO

Bax inhibitor-1 (BI-1) is a cell death suppression factor widely conserved in higher plants and animals. Overexpression of Arabidopsis BI-1 (AtBI-1) in plants confers tolerance to various cell death-inducible stresses. However, apart from the cell death-suppressing activity, little is known about the physiological roles of BI-1-overexpressing plants. In this study, we evaluated the effects of AtBI-1 overexpression on the rice metabolome in response to oxidative stress. AtBI-1-overexpressing rice cells in suspension displayed enhanced tolerance to menadione-induced oxidative stress compared with vector control cells, whereas AtBI-1 overexpression did not influence the increase of intracellular H(2)O(2) concentration or inhibition of oxidative stress-sensitive aconitase activity. Capillary electrophoresis-mass spectrometry (CE-MS)-based metabolome analysis revealed dynamic metabolic changes in oxidatively stressed rice cells, e.g. depletion of the central metabolic pathway, imbalance of the redox state and energy charge, and accumulation of amino acids. Furthermore, comparative metabolome analysis demonstrated that AtBI-1 overexpression did not affect primary metabolism in rice cells under normal growth conditions but significantly altered metabolite composition within several distinct pathways under cell death-inducible oxidative stress. The AtBI-1-mediated metabolic alteration included recovery of the redox state and energy charge, which are known as important factors for metabolic defense against oxidative stress. These observations suggest that although AtBI-1 does not affect rice metabolism directly, its cell death suppression activity leads to enhanced capacity to acclimate oxidative stress.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Metaboloma/genética , Oryza/genética , Oryza/metabolismo , Estresse Oxidativo/genética , Adaptação Fisiológica/genética , Aminoácidos/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Morte Celular/genética , Resistência a Medicamentos/genética , Eletroforese Capilar , Metabolismo Energético/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Espectrometria de Massas , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Oryza/citologia , Oxirredução , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Vitamina K 3/toxicidade , Vitaminas/toxicidade
9.
Toxicol Mech Methods ; 20(2): 96-104, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20100038

RESUMO

Excess hepatic iron generates reactive oxygen species that result in oxidative stress and oxidative damage to the liver. Vitamins have hitherto been considered to be a possible remedy. The aim of this study was to determine if high doses of delta-alpha-tocopherol supplementation in iron overload would ameliorate the oxidative stress. Four groups of 20 male Wistar albino rats were studied: group 1 (control) was fed normal diet, group 2 (Fe) 0.75% Ferrocene iron, group 3 (FV gp) 0.75% Ferrocene/delta-alpha-tocopherol (10x RDA), group 4 (V gp) normal diet/delta-alpha-tocopherol. After 12 months, serum iron, reduced glutathione, catalase, vitamin C, Oxygen Radical Absorbance Capacity, lipid peroxidation, 8-hydroxy-2'-deoxyguanosine (8-OHdG), aspartate transaminase (AST), and alanine transaminase (ALT) were measured. Vitamin C levels were: F gp = 5.04 +/- 0.09; FV gp = 5.85 +/- 0.13 (micromol/l) (p < 0.05). 8-hydroxy-2'-deoxyguanosine levels were: F gp = 143.6 +/- 6.4; FV gp = 179.2 +/- 18.2 (ng/ml) (p < 0.05). Oxidative liver damage, as determined by serum AST and ALT levels, was not attenuated by alpha-tocopherol. A positive correlation existed between vitamin C and 8-OHdG, suggesting possible delta-alpha-tocopherol toxicity.


Assuntos
Antioxidantes/toxicidade , Ácido Ascórbico/metabolismo , Desoxiguanosina/análogos & derivados , Sobrecarga de Ferro/induzido quimicamente , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Vitaminas/toxicidade , alfa-Tocoferol/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Administração Oral , Alanina Transaminase/sangue , Animais , Antioxidantes/administração & dosagem , Ácido Ascórbico/sangue , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Catalase/sangue , Desoxiguanosina/metabolismo , Modelos Animais de Doenças , Compostos Ferrosos , Glutationa/sangue , Ferro/sangue , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Metalocenos , Ratos , Ratos Wistar , Fatores de Tempo , Regulação para Cima , Vitaminas/administração & dosagem , alfa-Tocoferol/administração & dosagem
10.
Prog Neuropsychopharmacol Biol Psychiatry ; 33(2): 205-13, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19063930

RESUMO

Low resting heart rate is a strong and consistent predictor of conduct disorder and chronic aggression. Explanations such as fearlessness and low arousal-induced stimulus-seeking have been offered, assuming a causal association between the phenomena, but the origin of low heart rate and its significance for understanding aggression and violence remain obscure. Retinoids (vitamin A and its congeners) play important roles in embryogenesis and neural development. Several lines of evidence also suggest a causal role of retinoids in aggression as well as cognitive and mood disorders. The hypothesis is proposed that retinoid overexpression in utero induces, via a noradrenergic-to-cholinergic switch, alterations in cardiac functioning and hemodynamics resulting in low resting heart rate, brain structural and functional changes, minor physical anomalies, and persistent aggression. Retinoid toxicity occurring early in pregnancy could represent a final common pathway by which various prenatal challenges result in conduct disorder and chronic aggression (e.g., maternal cigarette smoking, alcohol consumption, drug use, exposure to environmental chemicals, stress, trauma or infection). Implications of the model for understanding related aspects of chronic aggression are discussed, as well as strategies for prevention and treatment.


Assuntos
Agressão/fisiologia , Frequência Cardíaca/fisiologia , Retinoides/toxicidade , Monitorização Ambulatorial da Pressão Arterial , Criança , Doença Crônica , Dieta , Humanos , Vias Neurais/efeitos dos fármacos , Retinoides/fisiologia , Terminologia como Assunto , Vitamina A/fisiologia , Vitamina A/toxicidade , Vitaminas/fisiologia , Vitaminas/toxicidade
11.
Arch Toxicol ; 83(11): 1021-30, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19669731

RESUMO

It was recently shown that 1-year chronic exposure of rats to tocotrienol (TT) induced highly proliferative liver lesions, nodular hepatocellular hyperplasia (NHH), and independently increased the number of glutathione S-transferase placental form (GST-P)-positive hepatocytes. Focusing attention on the pathological intrinsic property of NHH, a 104-week carcinogenicity study was performed in male and female Wistar Hannover rats given TT at concentrations of 0, 0.4 or 2% in the diet. The high-dose level was adjusted to 1% in both sexes from week 51 because the survival rate of the high-dose males dropped to 42% by week 50. At necropsy, multiple cyst-like nodules were observed, as in the chronic study, but were further enlarged in size, which consequently formed a protuberant surface with a partly pedunculated shape in the liver at the high dose in both sexes. Unlike the chronic study, NHH was not always accompanied by spongiosis, and instead angiectasis was prominent in some nodules. However, several findings in the affected hepatocytes such as minimal atypia, no GST-P immunoreactivity and heterogeneous proliferation, implied that NHH did not harbor neoplastic characteristics from increased exposure despite sustained high cell proliferation. On the other hand, in the high-dose females, the incidence of hepatocellular adenomas was significantly higher than in the control. There was no TT treatment-related tumor induction in any other organs besides the liver. Thus, the overall data clearly suggested that NHH is successively enlarged by further long-term exposure to TT, but does not become neoplastic. In contrast, TT induces low levels of hepatocellular adenomas in female rats.


Assuntos
Hiperplasia Nodular Focal do Fígado/induzido quimicamente , Hepatócitos/efeitos dos fármacos , Tocotrienóis/toxicidade , Vitaminas/toxicidade , Adenoma de Células Hepáticas/induzido quimicamente , Adenoma de Células Hepáticas/patologia , Animais , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Hiperplasia Nodular Focal do Fígado/patologia , Hepatócitos/metabolismo , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Masculino , Ratos , Ratos Wistar , Fatores Sexuais , Tocotrienóis/administração & dosagem , Vitaminas/administração & dosagem
12.
Arch Toxicol ; 83(11): 1001-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19593550

RESUMO

Menadione is a naphthoquinone used as a vitamin K source in animal feed that can generate reactive oxygen species (ROS) and cause apoptosis. Here, we examined whether menadione reduces development of preimplantation bovine embryos in a ROS-dependent process and tested the hypothesis that actions of menadione would be reduced by insulin-like growth factor-1 (IGF-1). Menadione caused a concentration-dependent decrease in the proportion of embryos that became blastocysts. All concentrations tested (1, 2.5, and 5.0 microM) inhibited development. Treatment with 100 ng/ml IGF-1 reduced the magnitude of the anti-developmental effects of the two lowest menadione concentrations. Menadione also caused a concentration-dependent increase in the percent of cells positive for the TUNEL reaction. The response was lower for IGF-1-treated embryos. The effects of menadione were mediated by ROS because (1) the anti-developmental effect of menadione was blocked by the antioxidants dithiothreitol and Trolox and (2) menadione caused an increase in ROS generation. Treatment with IGF-1 did not reduce ROS formation in menadione-treated embryos. In conclusion, concentrations of menadione as low as 1.0 muM can compromise development of bovine preimplantation embryos to the blastocyst stage of development in a ROS-dependent mechanism. Anti-developmental actions of menadione can be blocked by IGF-1 through effects downstream of ROS generation.


Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Vitamina K 3/toxicidade , Vitaminas/toxicidade , Animais , Apoptose/efeitos dos fármacos , Blastocisto/metabolismo , Bovinos , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Vitamina K 3/administração & dosagem , Vitaminas/administração & dosagem
13.
Regul Toxicol Pharmacol ; 53(1): 1-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18929610

RESUMO

In the present study, the acute, subacute and genetic toxicity of Coenzyme Q10 (CoQ10) in the form of Bio-Quinone (Pharma Nord, Denmark) was assessed. LD(50) of CoQ10 by oral treatment was greater than 20g/kg body weight in both female and male mice. Genotoxicity was assessed in mice by Ames test in Salmonella typhimurium strains TA97, TA98, TA100 and TA102, by bone marrow micronucleus test and sperm abnormality. Thirty-day subacute toxicity was conducted with oral daily dose at 0, 0.56, 1.13 and 2.25g/kg body weight in rats. No significant changes in body weight, food intake, behavior, mortality, hematology, blood biochemistry, vital organ weight, sperm abnormality, mutagenicity and micronucleus formation were observed and no clinical signs or adverse effects were detected by administration of CoQ10. These results support the safety of CoQ10 for oral consumption.


Assuntos
Espermatozoides/efeitos dos fármacos , Ubiquinona/análogos & derivados , Vitaminas/toxicidade , Administração Oral , Animais , Medula Óssea/metabolismo , Relação Dose-Resposta a Droga , Feminino , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes para Micronúcleos/métodos , Testes de Mutagenicidade , Ratos , Ratos Sprague-Dawley , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Espermatozoides/metabolismo , Fatores de Tempo , Testes de Toxicidade , Ubiquinona/administração & dosagem , Ubiquinona/toxicidade , Vitaminas/administração & dosagem
14.
Int J Pharm ; 571: 118717, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31610279

RESUMO

The fat-soluble vitamins lipid injectable emulsion, a parenteral supplement, commonly used for hospitalized patients to meet daily requirements of fat-soluble vitamins. This study attempts to reduce risk, improve the stability and safety of fat-soluble vitamins lipid injectable emulsion using a Quality by Design (QbD) approach. The quality target product profile and critical quality attributes were defined based on a comprehensive understanding of fat-soluble vitamins lipid injectable emulsions. The emulsions were prepared using a high-pressure homogenization method. Critical quality attributes (CQAs) were identified using risk assessment tools such as fishbone diagram and risk estimation matrix. The assay, mean droplet size, polydispersity index, zeta potential, and the volume-weighted percentage of fat greater than 5 µm (PFAT5) were identified as CQAs. Accordingly, three critical formulation and process parameters for the emulsions were the percentage of emulsifier, homogenization pressure, and homogenization recirculation. The design space was obtained via a design of experiment (DoE), and an optimum formulation was successfully prepared. All physicochemical attributes of the optimal formulation were within the design space (i.e., droplet size: 217.2 ±â€¯0.37 nm; polydispersity index: 0.115 ±â€¯0.012; PFAT5: less than 0.05%; zeta potential: -34.6 ±â€¯1.09 mV; and viscosity: 20.95 mPa at 0.1 s-1). The optimal formulation remained acceptable physicochemical stability at 25 ±â€¯2 °C/60% RH ±â€¯5% RH over a 12-month period. Safety of the optimal emulsion was evaluated as acceptable through the determination of lysophospholipid content and an in vitro hemolysis assay. In conclusion, an optimal lipid injectable emulsion for fat-soluble vitamins was successfully prepared using a QbD approach.


Assuntos
Composição de Medicamentos/normas , Emulsões Gordurosas Intravenosas/administração & dosagem , Lipídeos/química , Solventes/química , Vitaminas/administração & dosagem , Animais , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Eritrócitos , Emulsões Gordurosas Intravenosas/química , Emulsões Gordurosas Intravenosas/toxicidade , Hemólise/efeitos dos fármacos , Lipídeos/toxicidade , Tamanho da Partícula , Controle de Qualidade , Coelhos , Projetos de Pesquisa , Solventes/toxicidade , Testes de Toxicidade , Viscosidade , Vitaminas/química , Vitaminas/toxicidade
15.
Toxicol In Vitro ; 22(5): 1177-83, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18440196

RESUMO

Vitamin A (retinol) exerts a major role in several biological functions. However, it was observed that retinol induces oxidative stress on different cellular types. Catalase (EC 1.11.1.6; CAT) is a hydrogen peroxide metabolizing enzyme, and its activity and expression is widely used as an index to measure oxidative stress and perturbations in the cellular redox state. The aim of this study was to investigate the effects of retinol and its major biologically active metabolite, all-trans retinoic acid (RA), on CAT regulation. For this purpose, cultured Sertoli cells (a physiological target of vitamin A) were treated with retinol or RA. Retinol (7 microM, 14 microM) and RA (100 nM, 1 microM) enhanced intracellular reactive species production and increased CAT activity after 24 h of treatment. Retinol increased CAT immunocontent but did not alter CAT mRNA expression, while the increase in CAT activity by RA was not related to alterations in immunocontent or mRNA expression. In vitro incubation of purified CAT with retinol or RA did not alter enzyme activity.


Assuntos
Antineoplásicos/toxicidade , Catalase/metabolismo , Células de Sertoli/efeitos dos fármacos , Tretinoína/toxicidade , Vitamina A/toxicidade , Vitaminas/toxicidade , Animais , Catalase/genética , Células Cultivadas , Relação Dose-Resposta a Droga , Radicais Livres/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Células de Sertoli/enzimologia
16.
Toxicol In Vitro ; 22(5): 1205-12, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18474417

RESUMO

Even though RA is involved in differentiation and apoptosis of normal and cancer cells, being sometimes used as adjuvant in chemotherapy, its mechanisms of action involve multiple overlapping pathways that still remain unclear. Recent studies point out that RA exerts rapid and non-genomic effects, which are independent of RAR/RXR-mediated gene transcription. In this work, we reported that RA treatment for 24 h decreases cell viability, induces apoptosis dependent on caspase-3 activation, and activates the transcription factor AP-1 in cultured Sertoli cells. Moreover, RA induced a rapid and non-classical stimulation of ERK1/2. ERK1/2 activation was mediated by MEK1/2, and the protein synthesis inhibitor cycloheximide did not alter the pattern of RA-induced ERK1/2 phosphorylation. Pharmacological inhibition of MEK1/2-ERK1/2 pathway with UO126 blocked caspase-3 activation, decreased AP-1 binding to DNA and inhibited apoptosis. Overall, our data suggest that a rapid and non-genomic effect of RA upon MEK1/2-ERK1/2 pathway leads to caspase-3 activation and caspase-3-dependent apoptosis in cultured Sertoli cells. The non-canonical RA signaling presented in this work evokes new perspectives of RA action, which may play an important role in mediating early biological effects of RA modulating cell death in normal and tumor cells.


Assuntos
Apoptose/efeitos dos fármacos , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Células de Sertoli/efeitos dos fármacos , Tretinoína/toxicidade , Vitaminas/toxicidade , Animais , Butadienos/farmacologia , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cicloeximida/farmacologia , DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática , MAP Quinase Quinase 1/metabolismo , Masculino , Nitrilas/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Ratos , Células de Sertoli/enzimologia , Células de Sertoli/patologia , Fator de Transcrição AP-1/biossíntese , Fator de Transcrição AP-1/fisiologia , Transcrição Gênica/efeitos dos fármacos
17.
Nurse Pract ; 43(5): 22-30, 2018 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-29668516

RESUMO

Vitamin D deficiency is an increasing problem affecting all ages. Patients should be assessed for risk factors as part of preventive health maintenance. Vitamin D toxicity is a rare occurrence caused by oversupplementation and errors in food fortification. The connection between vitamin D deficiency and osteoporosis, is well established. However, a cause and effect relationship has yet to be established between vitamin D deficiency and many chronic illnesses. An evidence-based approach is treating patients for an underlying vitamin D deficiency in hopes of improving many chronic illnesses.


Assuntos
Deficiência de Vitamina D/complicações , Vitamina D/toxicidade , Vitaminas/toxicidade , Acidentes por Quedas , Doença de Alzheimer/etiologia , Asma/etiologia , Doenças Cardiovasculares/etiologia , Demência/etiologia , Diabetes Mellitus/sangue , Dieta , Humanos , Síndrome do Intestino Irritável/complicações , Neoplasias/mortalidade , Osteomalacia/etiologia , Desempenho Físico Funcional , Recomendações Nutricionais , Infecções Respiratórias/etiologia , Raquitismo/etiologia , Fatores de Risco , Vitamina D/fisiologia , Vitamina D/uso terapêutico , Deficiência de Vitamina D/etiologia , Vitaminas/uso terapêutico
18.
Nutrients ; 10(5)2018 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-29710765

RESUMO

Physical exercise is beneficial for general health and is an effective treatment for metabolic disorders. Vitamin E is widely used as dietary supplement and is considered to improve non-alcoholic fatty liver disease by reducing inflammation and dyslipidemia. However, increased vitamin E intake may interfere with adaptation to exercise training. Here, we explored how vitamin E alters the acute exercise response of the liver, an organ that plays an essential metabolic role during physical activity. Mice fed a control or an α-tocopherol-enriched diet were subjected to a non-exhaustive treadmill run. We assessed the acute transcriptional response of the liver as well as glucocorticoid signalling and plasma free fatty acids (FFA) and performed indirect calorimetry. Vitamin E interfered with the exercise-induced increase in FFA and upregulation of hepatic metabolic regulators, and it shifted the transcriptional profile of exercised mice towards lipid and cholesterol synthesis while reducing inflammation. Energy utilization, as well as corticosterone levels and signalling were similar, arguing against acute differences in substrate oxidation or glucocorticoid action. Our results show that high-dose vitamin E alters the metabolic and inflammatory response of the liver to physical exercise. The interference with these processes may suggest a cautious use of vitamin E as dietary supplement.


Assuntos
Antioxidantes/administração & dosagem , Fígado/efeitos dos fármacos , Esforço Físico , Vitaminas/administração & dosagem , alfa-Tocoferol/administração & dosagem , Adaptação Fisiológica , Animais , Antioxidantes/toxicidade , Colesterol/sangue , Corticosterona/sangue , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Ácidos Graxos não Esterificados/sangue , Mediadores da Inflamação/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Modelos Animais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Corrida , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Vitaminas/toxicidade , alfa-Tocoferol/toxicidade
19.
Neurotoxicology ; 28(6): 1191-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17727954

RESUMO

Vitamin A participates in the maintenance of normal hippocampal function during embryonic and postnatal stages of the vertebrate life. Some works demonstrated that vitamin A metabolites impair learning and induce a depression-like behavior in mice, among other effects. Since vitamin A has prooxidant effects on other experimental models, we decided to investigate whether vitamin A can induce oxidative stress in the adult rat hippocampus. We analyzed the sub acute effects of therapeutic (1000 and 2500 I.U./kg) or excessive (4500 and 9000 I.U./kg) vitamin A doses on the hippocampal redox state, as well as on levels of anxiety, and locomotory and exploratory activity. Vitamin A supplementation induced lipid peroxidation, protein carbonylation, and oxidation of the protein thiol content in the rat hippocampus in all periods analyzed. Increased superoxide dismutase (SOD) activity and decreased catalase (CAT) activity were also observed, which gives rise to an imbalance in the principal cellular enzymatic antioxidant system. Then, our results show, for the first time, that vitamin A induced oxidative stress in the adult rat hippocampus, is anxiogenic, and decreases locomotion in and exploration of an open field.


Assuntos
Ansiedade/induzido quimicamente , Comportamento Animal/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Vitamina A/toxicidade , Vitaminas/toxicidade , Envelhecimento/metabolismo , Animais , Catalase/metabolismo , Relação Dose-Resposta a Droga , Glutationa Peroxidase , Hipocampo/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxirredução , Carbonilação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Compostos de Sulfidrila/metabolismo , Superóxido Dismutase/metabolismo
20.
Toxicol Lett ; 173(3): 145-50, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17698304

RESUMO

Vitamin A is an essential micronutrient to the normal brain function. However, there is an increasing concern regarding the use of vitamin A at high doses even therapeutically. Here, we show that acute and chronic vitamin A supplementation induces oxidative stress to submitochondrial particles (SMP) isolated from rat cerebral cortex and cerebellum. Both chronic and acute vitamin A supplementation at therapeutic (1000 IU/kg or 2500 IU/kg) or excessive (4500 IU/kg or 9000 IU/kg) doses induced lipid peroxidation, protein carbonylation, and oxidation of protein thiol groups in cerebral cortex and cerebellum SMP. Furthermore, vitamin A supplementation induced an increase in the superoxide (O(2)(-)) anion production, indicating an uncoupling in the electron transfer chain (ETC). Locomotory and exploratory activity, which are associated to cerebral cortex and cerebellum, also were affected by both acute and chronic vitamin A supplementation. Vitamin A induced a decrease in both locomotory and exploratory behavior. Together, these results show that vitamin A could be toxic at the sub cellular level, inducing mitochondrial dysfunction and altering cerebral cortex and/or cerebellum-dependent behavior.


Assuntos
Cerebelo/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Suplementos Nutricionais/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Partículas Submitocôndricas/efeitos dos fármacos , Vitamina A/toxicidade , Vitaminas/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Cerebelo/metabolismo , Córtex Cerebral/metabolismo , Relação Dose-Resposta a Droga , Transporte de Elétrons/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Partículas Submitocôndricas/metabolismo , Compostos de Sulfidrila/metabolismo , Superóxidos/metabolismo , Fatores de Tempo
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