Altos níveis de leptina em adultos com obesidade e sua relação com a proteína bdnf
Data
2022-02-25
Autores
Rodrigues, Isabele dos Reis 
Orientadores
Caranti, Danielle Arisa
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Introdução: De acordo com a Organização Mundial da Saúde (OMS), obesidade é o excesso de
tecido adiposo a um nível prejudicial à saúde. Com o acúmulo de gordura, ocorre o aumento
proporcional de leptina, hormônio que atua no hipotálamo realizando o controle da saciedade.
Indivíduos com obesidade tendem a ter níveis muito elevados desse hormônio, estado que acarreta na
resistência à leptina por seus receptores. Além de isso resultar na piora da função homeostática,
estudos têm demonstrado que este quadro resulta na possível diminuição dos níveis séricos de BDNF,
uma neurotrofina fundamental na comunicação entre os neurônios e saúde do SNC. Esta hipótese
poderia explicar a relação entre a desregulação de leptina com a alteração das funções cerebrais,
mecanismos que, consequentemente, poderiam ser fator de risco para a gênese de doenças
neurodegenerativas.
Objetivo: O objetivo geral do presente estudo foi avaliar os impactos dos níveis elevados de leptina
na expressão da proteína BDNF em adultos com obesidade. Os objetivos específicos foram identificar
a relação dos níveis elevados de leptina e a gênese de doenças neurodegenerativas e sua correlação
com outras variáveis antropométricas como IMC, perímetro de pescoço, quadril e cintura.
Método: Tratou-se de estudo retrospectivo com visita ao banco de dados do Grupo de estudos da
obesidade (GEO) onde foram feitas avaliações entre adultos de 30 a 50 anos, participantes deste
mesmo grupo da Universidade Federal de São Paulo, com IMC entre 30 e 39.9 kg/m². As avaliações
foram: IMC, por meio da relação entre o peso e a altura ao quadrado (kg/m²), perímetro de pescoço,
perímetro de cintura e perímetro de quadril. As concentrações de leptina foram mensuradas por um
kit de radioimunoensaio e as concentrações de BDNF por meio de sua mensuração no plasma
sanguíneo.
Hipótese: acredita-se que a atividade da proteína BDNF esteja prejudicada nos indivíduos com
obesidade que obtenham altos níveis de leptina.
Resultados: A relação entre leptina e BDNF foi positiva (r = 0, 339, p < 0, 01), a leptina se relacionou
positivamente com CQ (r = 0, 339, p < 0,01) e negativamente com PP (r = -0, 346, p < 0,01) e com
PC (r = -0, 23, p < 0, 05). Houve diferença significativa entre as médias (p < 0,05) do primeiro e
terceiro tercil de BDNF e PQ, sendo positivas, entre primeiro e terceiro tercil de PP, sendo negativa
e diferença positiva entre o primeiro e segundo tercil de PQ.
Conclusões: A leptina em excesso não foi um fator causador da diminuição dos níveis séricos de
BDNF, logo não demonstrando risco para o desenvolvimento de doenças degenerativas por falta
dessa neurotrofina no cérebro. Apenas a variável perímetro de quadril foi diretamente proporcional
aos níveis de leptina, servindo de parâmetro para medição da quantidade desse hormônio neste caso.
Há a necessidade de mais estudos serem realizados sobre esta temática.
Introduction: According to World Health Organization (WHO), obesity is the excess of fat tissue in a prejudicial level to health. Due to the accumulation of fat, it occurs a proportional increase of leptin, a hormone that acts in hypothalamus controlling satiety. Obese individuals tend to have high levels of this hormone, state that causes leptin resistance by its receptors. In addition to this resulting in the worsening of homeostatic function, studies have demonstrated that the high quantity of this hormone entails a possible decrease of serical amount of BDNF, a fundamental neurotrophin to the communication between neurons and CNS health. This hypothesis could explain the relationship among the leptin dysregulation and cerebral function alterations, conditions that, consequently, could could be a risk factor to genesis of neurodegenerative disease. Objective: The general objective of this study was to assess the impacts of high levels of leptin in BDNF protein expression in obese adults. The specific objectives were to identify the relation among high levels of leptin and the genesis of neurodegenerative diseases and its correlation with other anthropometric variables such as BMI, neck, waist and hip circumference. Method: This was a retrospective study with a visit to the database of the Obesity Study Group (OSG) where assessments were made among adults aged 30 to 50 years, participants of that group at the Federal University of São Paulo, with BMI between 30 and 39.9 kg / m². Anthropometric data were used to measure BMI, through the relationship between weight and height squared (kg / m²), neck circumference, waist circumference and hip circumference. Leptin concentrations were measured using a radioimmunoassay kit and BDNF concentrations were measured using blood plasma. Hypotheses: it was believed that the activity of the BDNF protein is impaired in individuals with obesity who obtain high levels of leptin. Results: The relationship between leptin and BDNF was positive (r = 0.339, p < 0.01), leptin was positively related to CQ (r = 0.339, p < 0.01) and negatively to PP (r = - 0.346, p < 0.01) and to PC (r = -0.23, p < 0.05). There was a significant difference between the means (p < 0.05) of the first and third tertiles of BDNF and PQ, which were positive, negative difference between the first and third tertiles of PP and a positive difference between the first and second tertiles of PQ. Conclusions: Excess leptin was not a factor causing the decrease in serum levels of BDNF, thus not demonstrating a risk for the development of degenerative diseases due to the lack of this neurotrophin in the brain. Only the hip circumference variable was directly proportional to leptin levels, serving as a parameter for measuring the amount of this hormone. More studies on this topic are needed.
Introduction: According to World Health Organization (WHO), obesity is the excess of fat tissue in a prejudicial level to health. Due to the accumulation of fat, it occurs a proportional increase of leptin, a hormone that acts in hypothalamus controlling satiety. Obese individuals tend to have high levels of this hormone, state that causes leptin resistance by its receptors. In addition to this resulting in the worsening of homeostatic function, studies have demonstrated that the high quantity of this hormone entails a possible decrease of serical amount of BDNF, a fundamental neurotrophin to the communication between neurons and CNS health. This hypothesis could explain the relationship among the leptin dysregulation and cerebral function alterations, conditions that, consequently, could could be a risk factor to genesis of neurodegenerative disease. Objective: The general objective of this study was to assess the impacts of high levels of leptin in BDNF protein expression in obese adults. The specific objectives were to identify the relation among high levels of leptin and the genesis of neurodegenerative diseases and its correlation with other anthropometric variables such as BMI, neck, waist and hip circumference. Method: This was a retrospective study with a visit to the database of the Obesity Study Group (OSG) where assessments were made among adults aged 30 to 50 years, participants of that group at the Federal University of São Paulo, with BMI between 30 and 39.9 kg / m². Anthropometric data were used to measure BMI, through the relationship between weight and height squared (kg / m²), neck circumference, waist circumference and hip circumference. Leptin concentrations were measured using a radioimmunoassay kit and BDNF concentrations were measured using blood plasma. Hypotheses: it was believed that the activity of the BDNF protein is impaired in individuals with obesity who obtain high levels of leptin. Results: The relationship between leptin and BDNF was positive (r = 0.339, p < 0.01), leptin was positively related to CQ (r = 0.339, p < 0.01) and negatively to PP (r = - 0.346, p < 0.01) and to PC (r = -0.23, p < 0.05). There was a significant difference between the means (p < 0.05) of the first and third tertiles of BDNF and PQ, which were positive, negative difference between the first and third tertiles of PP and a positive difference between the first and second tertiles of PQ. Conclusions: Excess leptin was not a factor causing the decrease in serum levels of BDNF, thus not demonstrating a risk for the development of degenerative diseases due to the lack of this neurotrophin in the brain. Only the hip circumference variable was directly proportional to leptin levels, serving as a parameter for measuring the amount of this hormone. More studies on this topic are needed.
Descrição
Citação
RODRIGUES, Isabele dos Reis. Altos níveis de leptina em adultos com obesidade e sua relação com a proteína BDNF. 2022. 48 f. Trabalho de Conclusão de Curso (Graduação em Educação Física) - Instituto de Saúde e Sociedade, Universidade Federal de São Paulo, Santos, 2022.