Review of Polymorphism of the Calcium-Sensing Receptor Gene and Breast Cancer Risk.

Polymorphism of the calcium-sensing receptor gene (CaSR or CaR) has been associated with an increased risk for breast cancer. This receptor plays an important role in calcium homeostasis, and has also been detected in several tissues that are unrelated to calcium metabolism, such as the skin, brain, and breast. The calcium-sensing receptor on cellular level, it regulates cell differentiation, proliferation, cell death, and gene expression. In breast cancer cells, CaSR seems to stimulate secretion of the parathyroid hormone-related protein (PTHrP), which stimulates cellular proliferation. Likewise, some studies have supported not only an association between calcium receptor gene polymorphism and breast cancer risk, but also a higher aggressiveness and unfavorable outcomes in breast cancer, which led us to make a survey in Pubmed on the subject in the last 10 years. Thus, in the literature there is a paucity of studies on the subject and the aim of this review was to show the role of calcium-sensing receptor and its association with breast cancer risk.

Association between matrix metalloproteinase-9 gene polymorphism and breast cancer in Brazilian women.

OBJECTIVE: This study aimed to determine the relationship between rs17576 (MMP-9) polymorphism and increased cancer risk in a Brazilian breast cancer cohort. METHODS: This study included 141 women (71 breast cancer patients and 70 controls without breast cancer) who donated 3 mL of their peripheral blood for genomic DNA extraction. This DNA was then genotyped using a real-time polymerase chain reaction. RESULTS: The AG (rs17576) genotype was identified in 26 (18.43%) participants in the case group and in 22 (15.60%) participants in the control group (p=0.274), while the GG genotype was identified in ten (7.09%) participants in the case group and in one (0.70%) participant in the control group (p<0.003 - OR (95% CI) 13.13 (1.73, 593.08). No significant difference in the incidence rates was observed for AG or GG rs17576 genotypes in premenopausal women, p=0.813 and p=0.556, respectively. However, in postmenopausal women, the AG genotype was shown to occur in 14 (22.5%) participants in the case group and in 4 (6.45%) participants in the control (p<0.043), while GG genotype occurred in eight (12.90%) of the individuals in the case group and in none of the individuals in the control group (p<0.006). CONCLUSION: In this study, the MMP-9 rs17576 GG polymorphic variant was shown to be significantly associated with breast cancer risk in premenopausal women, while the AG and GG genotypes were associated with increased cancer risk in postmenopausal women.

A case-control study of Metallothionein-1 expression in breast cancer and breast fibroadenoma.

The overexpression of Metallothionein-1 (MT-1) may play an important role in breast cancer; however, few studies have compared MT-1 expression between breast cancer and fibroadenoma. A cross-sectional controlled study was performed in 66 premenopausal women, aged 20-49 years, who had been histologically diagnosed with breast fibroadenoma or breast cancer. The patients were divided into two groups: group A, control (fibroadenoma, n = 36) and group B, study (breast cancer, n = 30). Immunohistochemistry was performed on tissue samples of fibroadenoma and breast cancer patients to evaluate the expression of metallothionein using an anti-MT-1 polyclonal antibody (rabbit polyclonal anti-metallothionein-Catalog Number biorbyt-orb11042) at a dilution of 1:100. The data were analyzed using NOVA (p < 0.05). Microscopic analysis showed a higher concentration of anti-MT-1-stained nuclei in breast cancer tissues than in fibroadenoma tissues. The mean proportion of cells with anti-MT-1-stained nuclei was 26.93% and 9.10%, respectively, in the study and control groups (p < 0.001). Histological grade 3 tumors showed a significantly higher MT-1 expression than hitological grade 1 (p < 0.05), while breast tumors negative for estrogen-, progesterone- and HER2- receptors had a significantly higher MT-1 expression than positive breast tumors positive for these parameters (p < 0.05). MT-1 protein in women of reproductive age was significantly higher in breast cancer than in fibroadenoma in this study. Furthermore, there was higher MT-1 immunoreactivity in more aggressive tumors.

Expression of matrix metalloproteinase 2 and 9 in breast cancer and breast fibroadenoma: a randomized, double-blind study.

BACKGROUND: Matrix metalloproteinases (MMPs) 2 and 9 may play an important role in cell proliferation and dissemination of cancer. However, few studies have compared the expression of these proteins between breast cancer and fibroadenoma. MATERIAL AND METHODS: A randomized, double-blind study was carried out in 66 premenopausal women, aged 20-49 years, who had been diagnosed with fibroadenoma or breast cancer. The patients were divided into two groups: Group A, control (fibroadenoma, n=36) and Group B, study (cancer, n=30). Immunohistochemical analysis was performed using tissue samples of fibroadenoma and breast cancer to assess MMP-2 and MMP-9 antigen expression. Cells were considered positive if exhibiting brown cytoplasmic staining. Fisher's exact test was used to compare the percentage of cases with cells expressing MMP-2 and MMP-9 in control and study groups (p < 0.05). RESULTS: Light microscopy showed a higher concentration of cells with positive cytoplasmic staining for MMP-2 and MMP-9 expression in breast cancer than in fibroadenoma. The percentage of cases with cells expressing MMP-2 in the control and study groups was 41.67% and 86.11%, respectively (p < 0.0009), whereas the percentage of cases with cells expressing MMP-9 in groups A and B was 66.67% and 93.33%, respectively (p<0.0138). MMP-2 and MMP-9 positive expression was significantly higher in moderately differentiated tumors compared to well and poorly differentiated tumors, p <0.005 and p<0.001, respectively. CONCLUSIONS: The current study shows that MMP-2 and MMP-9 protein expression was significantly higher in the breast cancer than in the fibroadenoma and also in moderately differentiated breast cancer.

Bcl-2 antigen expression in luminal A and triple-negative breast cancer.

Biomarkers for the prognosis of breast cancer have been routinely used in clinical practice, including the expression of hormone receptors, Ki-67 and HER-2. More recently, Bcl-2 has been recognized as an important prognostic factor in breast cancer, although controversies persist with respect to the significance of its expression. The aim of the present study was to evaluate Bcl-2 antigen expression in luminal A and triple-negative breast cancer. Sixty women with invasive ductal carcinoma were included in the study and divided into two groups: Group A (luminal A) and Group B (triple-negative), with 30 cases in each group. Immunohistochemistry was performed on tissue sections to evaluate Bcl-2 antigen expression. Fisher's exact test was used to compare the proportions of cases with cells expressing Bcl-2 between the two subtype cancer groups, with statistical significance being established at p < 0.05. The number of cases with cells expressing Bcl-2 in Groups A and B was 26 (86.7%) and 12 (40.0%), respectively (p < 0.0003). In the present study, the expression of the anti-apoptotic protein Bcl-2 was greater in luminal A breast cancer tissue samples compared to triple-negative breast cancer.

Association between matrix metalloproteinase-9 gene polymorphism and breast cancer in Brazilian women

OBJECTIVE: This study aimed to determine the relationship between rs17576 (MMP-9) polymorphism and increased cancer risk in a Brazilian breast cancer cohort. METHODS: This study included 141 women (71 breast cancer patients and 70 controls without breast cancer) who donated 3 mL of their peripheral blood for genomic DNA extraction. This DNA was then genotyped using a real-time polymerase chain reaction. RESULTS: The AG (rs17576) genotype was identified in 26 (18.43%) participants in the case group and in 22 (15.60%) participants in the control group (p=0.274), while the GG genotype was identified in ten (7.09%) participants in the case group and in one (0.70%) participant in the control group (p<0.003 - OR (95% CI) 13.13 (1.73, 593.08). No significant difference in the incidence rates was observed for AG or GG rs17576 genotypes in premenopausal women, p=0.813 and p=0.556, respectively. However, in postmenopausal women, the AG genotype was shown to occur in 14 (22.5%) participants in the case group and in 4 (6.45%) participants in the control (p<0.043), while GG genotype occurred in eight (12.90%) of the individuals in the case group and in none of the individuals in the control group (p<0.006). CONCLUSION: In this study, the MMP-9 rs17576 GG polymorphic variant was shown to be significantly associated with breast cancer risk in premenopausal women, while the AG and GG genotypes were associated with increased cancer risk in postmenopausal women.

Oxidative stress and immunological alteration in women with preeclampsia.

OBJECTIVES: To determine plasma concentrations of malondialdehyde (MDA) and of inflammatory markers in women with preeclampsia. METHODS: A case-control study was conducted on 50 preeclamptic and 50 healthy pregnant women. The concentrations of MDA were determined by the method of thiobarbituric acid reactive substances. Markers of inflammation were determined by the multiplex method. RESULTS: The concentrations of MDA did not differ between groups (p > 0.05) and the preeclampsia group had significantly higher IL-6, IL-10, TNF-α and IL-6/IL-10 ratio, compared to those with normal pregnancy. CONCLUSIONS: The MDA is a nonspecific marker for oxidative stress in preeclampsia, and the gestantes with preeclampsia have immune dysfunction.

Nível de conhecimento e desidratação de jogadores juniores de futebol / Level of knowledge and dehydration of junior soccer players / Nivel de conocimiento y deshidratación en jugadores juveniles de fútbol

RESUMO Introdução: A desidratação é uma condição fisiológica que decorre de perda hídrica prolongada, com consequente elevação da temperatura corporal e redução do desempenho dos atletas. Objetivo: Avaliar o nível de conhecimento e o grau de hidratação de jogadores juniores de futebol. Métodos: Trata-se de um estudo transversal, envolvendo 14 jogadores de futebol, que foram avaliados quanto ao percentual de perda de peso após exercício (desidratação relativa), pH e densidade da urina e nível de conhecimento sobre hidratação. A análise estatística foi realizada por meio do software SPSS versão 18.0, utilizando um intervalo de confiança de 95%, com nível de significância com p < 0,05. Resultados: Pôde-se verificar que 92,85% dos jogadores apresentaram eutrofia e os valores médios de desidratação relativa, densidade urinária e pH foram de -0,89%, 1.034,43, e 5,64, respectivamente, com o que se revelou desidratação para as posições com maior desgaste físico e 48,9% dos jogadores apresentam conhecimento regular sobre hidratação. Conclusão: A desidratação encontrada em jogadores juniores pode ser influenciada por diferentes posições em campo e esquema tático do jogo.

ABSTRACT Introduction: Dehydration is a physiological condition that results from prolonged water loss, with consequent elevation of body temperature and reduced athletes' performance. Objective: To evaluate the level of knowledge and the degree of hydration of junior soccer players. Methods: This is a cross-sectional study involving 14 soccer players who were evaluated for weight loss after exercise (relative dehydration), pH and density of urine and the level of knowledge about hydration. Statistical analysis was performed using SPSS software version 18.0, using a 95% confidence interval, with significance level of p<0.05. Results: It was possible to verify that 92.85% of the players were eutrophic and the mean values of relative dehydration, urinary density and pH were of -0.89%, 1,034.43, and 5.64, respectively, revealing dehydration for positions with greater physical wear and 48.9% of the players had a regular knowledge about hydration. Conclusion: The dehydration found in junior players can be influenced by different positions in the field and tactical scheme of the game.

RESUMEN Introducción: La deshidratación es una condición fisiológica que resulta de la pérdida prolongada de agua, con la consiguiente elevación de la temperatura corporal y la reducción de rendimiento de los atletas. Objetivo: Evaluar el nivel de conocimiento y el grado de hidratación de jugadores de fútbol juvenil. Métodos: Se trata de un estudio transversal que incluyó a 14 jugadores de fútbol, que fueron evaluados para el porcentaje de pérdida de peso después del ejercicio (deshidratación relativa), el pH y la densidad de la orina y el nivel de conocimiento sobre la hidratación. El análisis estadístico se realizó mediante el software SPSS versión 18.0 usando un intervalo de confianza de 95%, con un nivel de significación de p < 0,05. Resultados: Se verificó que 92,85% de los jugadores eran eutróficos y los valores promedio de deshidratación relativa, densidad y pH urinario fueron -0,89%, 1.034,43, y 5,64, respectivamente, que reveló deshidratación en las posiciones con mayor desgaste físico y que el 48,9% de los jugadores tiene un conocimiento normal sobre la hidratación. Conclusión: La deshidratación encontrada en jugadores juveniles puede ser influenciada por diferentes posiciones en el campo y el juego táctico.

Relação entre o consumo de gordura saturada e os fatores de risco cardiovascular em pessoas com síndrome de Down / Relationship between the consumption in fat saturated and cardiovascular risk factors in people with Down syndrome

Objetivo: Avaliar a relação entre o consumo de gordura saturada e o risco cardiovascular em pessoas com síndrome de Down. Estudo transversal, realizado em 33 crianças e adolescentes com síndrome de Down atendidos no Centro Integrado de Educação Especial, de ambos os sexos, com idade entre 3 e 14 anos. Método: Para determinação do estado nutricional, foram utilizadas as curvas específicas. Na avaliação do consumo alimentar foi utilizado o recordatório 24 horas, analisado pelo software "Nutwin", versão 1.5. Para identificação do risco cardiovascular, foram realizadas medidas de circunferências da cintura e pescoço, índice de conicidade, além da pressão arterial. A análise estatística dos dados foi realizada por meio do SPSS v. 18.0, utilizando os testes t de Student, para comparar os valores médios, e a correlação de Pearson, para verificar associação entre as variáveis. Resultados: O indicador P/I revelou excesso de peso para 19,04% do sexo feminino, enquanto que o consumo de gordura saturada esteve inadequado para ambos os sexos, sendo 75% e 85,71%, para meninos e meninas, respectivamente. Quanto ao risco cardiovascular, os valores médios e desvio padrão encontrados para o índice de conicidade foram de 1,02±0,47 e 1,24±0,34 para meninos e meninas, respectivamente, com diferença significativa entre os sexos (p<0,05). Conclusão: Os participantes apresentam risco cardiovascular e a inadequação no consumo de gordura saturada contribui para essa condição.(AU)

Objectives: To evaluate the relationship between the consumption of saturated fat and cardiovascular risk in people with Down syndrome. Cross-sectional study conducted in 33 children and adolescents with Down syndrome seen at Centro Integrado de Educação Especial, of both sexes, aged between 3 and 14 years. Methods: To determine the nutritional status we used the specific curves. In assessing the food intake was used the 24-hour recall, analyzed by software "Nutwin" 1.5 version. To identify cardiovascular risk, waist and neck circumferences, conicity index, as well as blood pressure were measured. Statistical analysis was performed using SPSS v. 18.0 using the t test Student to compare the mean values and the Pearson correlation to verify the association between variables. Results: The P / I indicator revealed excess weight to 19.04% female, while saturated fat intake was inadequate for both sexes, 75% and 85.71% for boys and girls, respectively. As the cardiovascular risk mean values and standard deviation found for conicity index were 1.02±0.47 and 1.24±0.34 for boys and girls, respectively, with a significant difference between the sexes (p<0.05). Conclusion: Participants have cardiovascular risk and inadequate in saturated fat consumption contributes to this condition.(AU)

Relação entre parâmetros de adiposidade e proteína C reativa em mulheres com câncer de mama / Relationship between adiposity parameters and C-reactive protein in women with breast cancer

Introdução: O câncer de mama é uma doença multifatorial que envolve desequilíbrio entre fatores genéticos, dietéticos e hormonais. Pesquisas mostram que o excesso de peso corporal, associado a diversas desordens metabólicas como a inflamação crônica de baixo grau, parece estar envolvido no desenvolvimento e progressão da doença. Assim, objetivo use avaliar a relação entre os parâmetros de adiposidade e as concentrações séricas de proteína C reativa em mulheres com câncer de mama. Métodos: Estudo transversal com casos e controles, envolvendo 68 mulheres, na faixa etária entre 20 e 59 anos, distribuídas em dois grupos: caso (câncer de mama, n=34) e controle (sem câncer de mama, n=34). Foram realizadas medidas do índice de massa corpórea e da circunferência da cintura. A determinação da proteína C reativa sérica foi pelo método enzimático colorimétrico. Resultados: Os valores médios do índice de massa corpórea das mulheres com câncer de mama foram de 26,17 ± 4,91 kg/m² e 22,78 ± 1,36 Kg/m² para o controle (p <0,05). Houve correlação positiva entre o índice de massa corpórea, a circunferência da cintura e as concentrações séricas de proteína C reativa (p=0,036 e p=0,009, respectivamente). Conclusão: A partir da análise dos dados, verifica-se uma possível influência dos parâmetros de adiposidade sobre as concentrações séricas de proteína C reativa nas mulheres com câncer de mama, evidenciando a participação do acúmulo de gordura corporal no desenvolvimento dessa doença (AU)

Introduction: Breast cancer is a multifactorial disease involving imbalance between genetic, dietary and hormonal factors. Research has shown that overweight associated with various metabolic disorders, such as chronic low-grade inflammation, which seems to be involved in development and progression of breast cancer. The objective was to evaluate the relationship between adiposity parameters and serum concentrations of C-reactive protein in women with breast cancer. Methods: Cross-sectional study with cases and controls, involving 68 women, aged between 20 and 59 years, divided into two groups: case (breast cancer, n = 34) and control (without breast cancer, n = 34). Body mass index and waist circumference measurements were performed. The determination of serum C-reactive protein was by enzymatic colorimetric method. Results: The mean body mass index of women with breast cancer were 26.17 ± 4.91 kg/m² and 22.78 ± 1.36 kg/m² for the control (p< 0.05). The average concentration of C-reactive protein of women with breast cancer were 2.33 ± 3.57 mg/L and 1.90 ± 0.89 mg/L for the control (p< 0.05). There was a positive correlation between body mass index, waist circumference and serum concentrations of C-reactive protein (p=0.036 and p=0.009, respectively). Conclusion: From data analysis, there is a possible influence of adiposity parameters on serum concentrations of C-reactive protein in women with breast cancer, highlighting the participation of body fat accumulation in the development of this disease (AU)

Influência da hipomagnesemia sobre a homeostase do ferro e estresse oxidativo no diabetes mellitus tipo 2 / Influence of hypomagnesemia on iron homeostasis and oxidative stress in type 2 diabetes mellitus

OBJECTIVE: This review aims to bring updated information about the influence of magnesium deficiency on iron homeostasis and oxidative stress in type 2 diabetics. Data source: A bibliographic search was conducted in the databases Bireme, SciELO, Science Direct, PubMed and Portal.periodicos.Capes using the following descriptors: "diabetes mellitus", "magnesium", "iron", "oxidative stress" and "malondialdehyde". Fifty articles related to this literature were selected. Data synthesis: Several studies have shown the influence of hypomagnesemia on oxidative stress in type 2 diabetics. Deficiency of this mineral seems to be related to the induction of hemolysis, which favors the release of iron with overload of this mineral in the body, allowing an increase of the hydroxyl radical through the Fenton reaction and, consequently, oxidative stress. The increase in free iron contributes significantly to the manifestation of lipid peroxidation, which triggers a sequence of lesions in the cell with loss of selectivity in ion exchange and release of the contents of organelles, such as the hydrolytic enzymes of lysosomes, and the formation of cytotoxic products, such as malondialdehyde. CONCLUSIONS: There is scientific evidence that magnesium deficiency alters iron compartmentalization in the body; however, new studies are needed to bring information that would enable the biochemical understanding of the importance of the balance of magnesium and iron concentrations in protecting against the oxidative stress present in type 2 diabetes

OBJETIVO: Esta revisão visa trazer informações atualizadas sobre a influência da deficiência de magnésio na homeostase do ferro e estresse oxidativo em diabéticos tipo 2. Fonte de dados: O levantamento bibliográfico foi realizado nas bases de dados Bireme, Scielo, Science Direct, periódicos Capes e Pubmed com os seguintes descritores: "diabetes mellitus", "magnésio", "ferro", "estresse oxidativo" e "malondialdeído". Foram selecionados 50 artigos entre os relacionados por essa pesquisa bibliográfica. Síntese dos dados: Diversos estudos têm mostrado a influência da hipomagnesemia sobre o estresse oxidativo em diabéticos tipo 2, sendo que a deficiência desse mineral parece estar relacionada à indução da hemólise dos eritrócitos, que favorece a liberação do ferro com sobrecarga desse mineral no organismo, o que possibilita aumento do radical hidroxila por meio da reação de Fenton e, consequentemente, o estresse oxidativo. O aumento de ferro livre contribui de forma relevante para a manifestação da peroxidação lipídica, que desencadeia sequência de lesões na célula, com perda da seletividade na troca iônica e liberação do conteúdo de organelas, como as enzimas hidrolíticas dos lisossomas e a formação de produtos citotóxicos, como o malondialdeído. CONCLUSÕES: Há evidências científicas de que a deficiência de magnésio altera a compartimentalização do ferro no organismo, entretanto a realização de novos estudos é necessária para trazer informações que permitam o entendimento bioquímico da importância do equilíbrio das concentrações de magnésio e ferro na proteção contra o estresse oxidativo presente no diabetes tipo 2

Influence of magnesium on biochemical parameters of iron and oxidative stress in patients with type 2 diabetes / Influencia de magnesio en la bioquímica del hierro y el estrés oxidativo en pacientes con diabetes tipo 2

Introduction: Studies have shown that oxidative stress, found in patients with type 2 diabetes, may be due to changes in the metabolism of minerals, such as magnesium and iron. Data related to compartmentalization of these minerals in diabetes are scarce and controversial. Objective: This study assessed the influence of magnesium on biochemical parameters of iron and oxidative stress in patients with type 2 diabetes. Methods: A case-control study in male and female subjects aged 27-59 years, divided into two groups: type 2 diabetes (n=40) and control (n=48). Intake of magnesium and iron was assessed by three-day food record. Plasma, erythrocyte and urinary levels of magnesium, serum iron, ferritin, total iron binding capacity, fasting glucose, glycated hemoglobin, insulin, creatinine clearance and plasma thiobarbituric acid reactive substances (TBARS) were analyzed. Results and Discussion: Magnesium intake and plasma magnesium were lower in diabetic subjects. There was low urinary magnesium excretion, with no difference between groups. Although normal, the diabetic group had lower serum iron and ferritin concentrations compared to control subjects. Plasma TBARS in diabetic patients was higher than control while creatinine clearance was lower. An inverse correlation between erythrocyte magnesium and serum iron and ferritin was observed in the diabetes group. Conclusions: Diabetes induced hypomagnesemia and this, associated with chronic hyperglycemia, may have enhanced oxidative stress. Erythrocyte magnesium may have contributed to prevent iron overload and worsening of oxidative stress and hyperglycemic status (AU)

Introducción: Los estudios han demostrado que el estrés oxidativo, que se encuentra en pacientes con diabetes tipo 2, puede ser debido a cambios en el metabolismo de los minerales, como el magnesio y el hierro. Los datos relacionados con la compartimentación de estos minerales en la diabetes son pocos y cuestionables. Objetivos: Evaluar la influencia del magnesio sobre parámetros bioquímicos de hierro y el estrés oxidativo en pacientes con diabetes tipo 2. Métodos: Estudio caso-control en los sujetos masculinos y femeninos de edad 27 a 59 años, divididos en dos grupos: la diabetes tipo 2 (n = 40) y control (n = 48). La ingesta de magnesio y hierro se evaluó por tres días registro de alimentos. Plasma, eritrocitos y los niveles urinarios de magnesio, hierro sérico, ferritina, capacidad total de fijación del hierro, glucosa en ayunas, hemoglobina glucosilada, la insulina, el aclaramiento de creatinina y el plasma se analizaron tiobarbitúrico sustancias reactivas al ácido (TBARS). Resultados y Discusión: La ingesta de magnesio y el magnesio en plasma fueron más bajos en los pacientes diabéticos. Hubo baja excreción urinaria de magnesio, sin diferencias entre los grupos. Aunque lo normal, el grupo de diabéticos tenían concentraciones de hierro y ferritina sérica inferiores en comparación con los sujetos control. TBARS plasmáticos en los pacientes diabéticos fue mayor que en el control, mientras que la depuración de creatinina fue menor. Se observó una correlación inversa entre el magnesio y el hierro en suero de los eritrocitos y la ferritina en el grupo de diabetes Conclusiones: Diabetes hipomagnesemia inducida y esto, asociado a la hiperglucemia crónica, pueden haber mejorado el estrés oxidativo. Magnesio eritrocitaria puede haber contribuido a evitar la sobrecarga de hierro y el empeoramiento de estrés oxidativo y el estado de hiperglucemia (AU)

Influência da hipovitaminose D no diabetes mellitus tipo 2 / Influence of hipovitaminose D in type 2 diabetes mellitus

A vitamina D e seus pró-hormônios possuem funções importantes no metabolismo da glicose. A deficiência de vitamina D está associada à resistência à insulina e ao diabetes mellitus tipo 2 em humano..O objetivo desta revisão é trazer informações atualizadas sobre a influência da hipovitaminose D no controle glicêmico. Realizou-se um levantamento bibliográfico, mediante consulta à base de dados PubMed, SciELO e Lilacs. A deficiência de vitamina D é uma epidemia mundial reconhecida entre crianças e adultos e pode ter relevância na patogênese do diabetes mellitus tipo 2. Esta vitamina atua diretamente nas células b-pancreáticas facilitando a secreção de insulina a partir da ligação da 1,25(OH)2D3 ao seu receptor nuclear VDR e indiretamente, por meio da regulação do fluxo de cálcio nessas células, pois alterações nas concentrações desse mineral podem levar à resistência periférica à ação de insulina, a partir da redução da transdução de sinal na atividade do transporte de glicose. Além disso, a hipovitaminose D contribui para o aumento da inflamação crônica de baixo grau associada à resistência à insulina, contribuindo para apoptose das células b-pancreáticas. Assim, novos estudos sobre a participação da vitamina D em mecanismos envolvidos na etiologia do diabetes mellitus tipo 2 poderão esclarecer os benefícios da suplementação com esse nutriente como estratégia terapêutica no controle dessa doença crônica...