Associa????o entre os polimorfismos BsmI e FokI do gene VDR, n??veis s??ricos de 25(OH)D e susceptibilidade ?? osteoporose em idosas

Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-06-29T13:16:18Z No. of bitstreams: 1 RafaelaRamosDissertacao2016.pdf: 1381332 bytes, checksum: 48e260b92a921bf25100218751857586 (MD5)Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-06-29T13:16:40Z (GMT) No. of bitstreams: 1 RafaelaRamosDissertacao2016.pdf: 1381332 bytes, checksum: 48e260b92a921bf25100218751857586 (MD5)Made available in DSpace on 2017-06-29T13:16:40Z (GMT). No. of bitstreams: 1 RafaelaRamosDissertacao2016.pdf: 1381332 bytes, checksum: 48e260b92a921bf25100218751857586 (MD5) Previous issue date: 2016-06-14Osteoporosis (OP) is a common osteometabolic disease among the elderly and may be associated with genetic components that influence bone metabolism. Due to regulatory action of vitamin D in osteomineral physiology, the expression of the vitamin D receptor gene (VDR) in bone tissue, it is able to influence the genetic determinants of bone mineral density (BMD) and the OP. Studies report the existence of polymorphisms related to the pathogenesis of OP, which can lead to changes in the mechanisms of the action of vitamin D. The BsmI and FokI polymorphisms were associated with changes in BMD suggesting thus a higher incidence and prevalence of fractures due to bone fragility. The objective of this study was to associate the presence of BsmI and FokI polymorphisms located in VDR gene, serum levels of 25(OH)D and susceptibility to OP for elderly women. It was observed that 58% of the study sample had levels of 25(OH)D below the threshold considered sufficient and 62% showed changes in BMD values consistent with the diagnosis of osteopenia or osteoporosis. For elderly women, vitamin D levels are not related to the reduction of BMD and presence of polymorphisms. In the evaluation of polymorphic sites it was found that, in this sample, 28% were positive for FokI polymorphism and 10% were positive for BsmI. The described results show that in elderly women, the BsmI polymorphisms FokI and are not related to vitamin D and osteoporosis.A osteoporose (OP) ?? uma afec????o osteometab??lica comum em idosos, associada ou n??o a componentes gen??ticos que influenciam no metabolismo ??sseo. Devido ?? a????o reguladora da vitamina D na fisiologia osteomineral, a express??o do gene receptor da vitamina D (VDR) no tecido ??sseo ?? capaz de exercer influ??ncia na determina????o gen??tica da densidade mineral ??ssea (DMO) e OP. Estudos reportam a exist??ncia de polimorfismos relacionados com a etiopatogenia da OP os quais podem determinar altera????es nos mecanismos de a????o da vitamina D. Os polimorfismos BsmI e FokI foram associados com varia????es na DMO sugerindo uma maior incid??ncia e preval??ncia de fraturas por fragilidade ??ssea. Desta forma, o objetivo deste estudo foi associar a presen??a dos polimorfismos BsmI e FokI localizados no gene VDR, as concentra????es s??ricas de 25-hidroxivitamina D (25(OH)D) e a susceptibilidade ?? osteoporose em idosas. Para tanto, foram inclu??das 50 idosas com m??dia de idade de 71,74 ?? 7,80 anos (60 ??? 94 anos). Os polimorfismos BsmI e FokI foram pesquisados e os dados sobre os n??veis de 25(OH)D e DMO foram coletados mediante acompanhamento ambulatorial. Observou-se que 58% da amostra estudada possui n??veis de 25(OH)D abaixo do limiar considerado suficiente e 62% apresentaram altera????es nos valores de DMO compat??veis com o diagn??stico de osteopenia ou osteoporose. Nas idosas avaliadas os n??veis de vitamina D n??o est??o relacionados com a redu????o da DMO e presen??a dos polimorfismos. Na avalia????o dos s??tios polim??rficos verificou-se que, nessa amostra, 28% apresentaram resultado positivo para o polimorfismo FokI e 10% apresentaram positividade para BsmI. Os resultados descritos evidenciam que, nas idosas avaliadas, os polimorfismos BsmI e FokI n??o se encontram relacionados com os n??veis de vitamina D e osteoporose