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Introduction: adequate iodine intake during pregnancy is essential for the synthesis of thyroid hormones, which are important for the physiological functions of the mother and appropriate maturation of the central nervous system of the fetus. Objective: the objective of the present study was to determine the levels of urinary iodine excretion and thyroid function, antioxidants and oxidative stress markers in pregnant women. Methods: the study was conducted on 191 pregnant women and 62 non-pregnant women who were evaluated regarding nutritional status. Analyses of urinary iodine, of oxidative stress markers and thyroid function were performed, revealing iodine insufficiency in 81 pregnant women. Results: there was no change in the thyroid stimulating hormone concentration in 89% of the pregnant women. Antithyroperoxidase antibody values were higher in the control group compared to the pregnant women's group (64.5% and 12.6%, respectively) and antithyroglobulin antibody values were also higher in the control group (11.6%). Assessment of oxidative stress revealed higher levels of advanced oxidation protein products, of total antioxidant capacity and of superoxide dismutase antioxidants in pregnant women. Classification of ioduria with respect to oxidative stress markers revealed lower α-tocopherol levels for the pregnant women with iodine insufficiency. Conclusion: on this basis, the results suggest that iodine insufficiency did not induce changes in thyroid stimulating hormone levels or antibodies and those pregnant women with adequate urinary iodine excretion had a better profile of the α-tocopherol antioxidant, indicating that iodine may play a significant role in antioxidant capacity during gestation. Resumen Introducción: la ingesta adecuada de yodo durante el embarazo es esencial para la síntesis de las hormonas tiroideas, que son importantes para las funciones fisiológicas de la madre y la maduración apropiada del sistema nervioso central del feto. Objetivo: el objetivo del presente estudio fue determinar los niveles de excreción de yodo urinario y función tiroidea, antioxidantes y marcadores de estrés oxidativo en mujeres embarazadas. Métodos: el estudio se realizó en 191 mujeres embarazadas y 62 mujeres no embarazadas que fueron evaluadas con respecto al estado nutricional. Se realizaron análisis de yodo urinario, marcadores de estrés oxidativo y función tiroidea, que revelaron insuficiencia de yodo en 81 embarazadas. Resultados: no hubo cambios en la concentración de hormona estimulante tiroidea en el 89% de las mujeres embarazadas. Los valores de anticuerpos antitiroperoxidasa fueron mayores en el grupo control en comparación con el grupo de mujeres embarazadas (64,5% y 12,6%, respectivamente) y los de anticuerpos antitiroglobulina fueron también mayores en el grupo control (11,6%). La evaluación del estrés oxidativo reveló niveles más altos de productos avanzados de proteína de oxidación, de capacidad antioxidante total y de antioxidantes de superóxido dismutasa en mujeres embarazadas. La clasificación de la yoduria con respecto a marcadores de estrés oxidativo reveló menores niveles de α-tocopherol para las mujeres embarazadas con insuficiencia de yodo. Conclusión: sobre esta base, los resultados sugieren que la insuficiencia de yodo no indujo cambios en los niveles de hormona estimulante de la tiroides o anticuerpos y las mujeres embarazadas con excreción urinaria adecuada de yodo tuvieron un mejor perfil del antioxidante α-tocopherol, lo que indica que el yodo puede desempeñar un papel significativo en la capacidad antioxidante durante la gestación.

Introduction: adequate iodine intake during pregnancy is essential for the synthesis of thyroid hormones, which are important for the physiological functions of the mother and appropriate maturation of the central nervous system of the fetus. Objective: the objective of the present study was to determine the levels of urinary iodine excretion and thyroid function, antioxidants and oxidative stress markers in pregnant women. Methods: the study was conducted on 191 pregnant women and 62 non-pregnant women who were evaluated regarding nutritional status. Analyses of urinary iodine, of oxidative stress markers and thyroid function were performed, revealing iodine insufficiency in 81 pregnant women. Results: there was no change in the thyroid stimulating hormone concentration in 89% of the pregnant women. Antithyroperoxidase antibody values were higher in the control group compared to the pregnant women's group (64.5% and 12.6%, respectively) and antithyroglobulin antibody values were also higher in the control group (11.6%). Assessment of oxidative stress revealed higher levels of advanced oxidation protein products, of total antioxidant capacity and of superoxide dismutase antioxidants in pregnant women. Classification of ioduria with respect to oxidative stress markers revealed lower α-tocopherol levels for the pregnant women with iodine insufficiency. Conclusion: on this basis, the results suggest that iodine insufficiency did not induce changes in thyroid stimulating hormone levels or antibodies and those pregnant women with adequate urinary iodine excretion had a better profile of the α-tocopherol antioxidant, indicating that iodine may play a significant role in antioxidant capacity during gestation.

Submitted by Luciana Abrão de Oliveira Restini Oliveira (luciana.abraonutri@gmail.com) on 2016-04-29T15:05:13Z No. of bitstreams: 1 Tese Luciana Abrão.pdf: 758211 bytes, checksum: 66d580b56d5bc28949f49defc70b57eb (MD5) Bitstreams deleted on 2016-10-27T11:27:33Z: restini_lao_dr_arafcf.pdf,. Added 1 bitstream(s) on 2016-10-27T11:28:05Z : No. of bitstreams: 1 000866332.pdf: 560429 bytes, checksum: 981780d89948d032bb6ebac21b1396ec (MD5) Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-02T18:12:48Z (GMT) No. of bitstreams: 1 restini_lao_dr_arafcf.pdf: 758211 bytes, checksum: 66d580b56d5bc28949f49defc70b57eb (MD5) Made available in DSpace on 2016-05-02T18:12:48Z (GMT). No. of bitstreams: 1 restini_lao_dr_arafcf.pdf: 758211 bytes, checksum: 66d580b56d5bc28949f49defc70b57eb (MD5) Previous issue date: 2015-12-04 A ingestão adequada de iodo durante a gestação é essencial para a síntese dos hormônios tireoidianos, que são importantes para as funções fisiológicas da mãe e para uma adequada maturação do sistema nervoso central do feto. Os efeitos da deficiência e/ou excesso de iodo são evidentes em todas as idades e se manifestam desde a fase fetal. O presente estudo teve como objetivo avaliar a excreção urinária de iodo, a função tireoidiana, e concentração séricas de antioxidantes e marcadores do estresse oxidativo em gestantes. Participaram do estudo 191 gestantes e 62 mulheres não gestantes que foram avaliadas segundo o estado nutricional e foram realizadas análises de iodo na urina, marcadores de estresse oxidativo e função tireoidiana. A partir das análises realizadas, foi observada insuficiência de iodo em 81 gestantes. Não houve alteração nas concentrações de TSH para 89% das gestantes. Os valores de anti-TPO foram superiores para o grupo controle em comparação com o grupo gestante (64,5% e 12,6%, respectivamente). Para o anti-TG, o grupo controle também apresentou valores maiores (11,6%). Não houve alteração significativa nos anticorpos quanto à sua classificação em relação aos valores de TSH e iodúria. A avaliação do estresse oxidativo revelou níveis de AOPP superiores para as gestantes e maiores níveis dos antioxidantes CAT e SOD. A classificação de iodúria com relação aos marcadores de estresse oxidativo revelou menores níveis de α-tocoferol para as gestantes com insuficiência de iodo. Sendo assim, os resultados sugerem que a insuficiência de iodo não foi capaz de induzir alterações nos níveis de TSH e anticorpos e que mulheres grávidas com excreção urinária de iodo adequada apresentaram melhor perfil do antioxidante α-tocoferol, indicando que o iodo pode desempenhar um papel significativo na capacidade antioxidante durante a gestação. Adequate intake of iodine during pregnancy is essential for synthesis of thyroid hormones, which are important for the physiological functions of the mother and proper maturation of the central nervous system of the fetus. The effects of disability and/or over are evident in all ages and manifest in the fetal stage. This study aimed to evaluate the urinary excretion levels of iodine, thyroid function and markers of oxidative stress in pregnant women. The study enrolled 191 pregnant women and 62 non-pregnant women who were evaluated according to the nutritional status and were held iodine analysis in urine, thyroid function and oxidative stress markers. From the analyzes, iodine deficiency was observed in 81 pregnant women. There was no change in TSH concentrations to 89% of pregnant women. The anti-TPO levels were higher in the control group compared to the pregnant group (64,5% and 12,6%, respectively). For anti-TG, the control group also showed higher values (11,6%). There was no significant change in antibodies and their classification about TSH levels and urinary iodine. Evaluation of oxidative stress revealed AOPP levels greater for pregnant women and higher levels of antioxidants SOD and CAT. Urinary iodine classification with respect to oxidative stress markers showed lower levels of α-tocopherol for pregnant women with iodine insufficiency. Thus, the results suggest that iodine deficiency was not able to induce altered levels of TSH and antibodies and pregnant women with urinary excretion of appropriate iodine showed a better profile of the α-tocopherol antioxidant, indicating that the iodine may play a role significant antioxidant capacity during pregnancy.