Selenium status and oxidative stress in obese: Influence of adiposity.

BACKGROUND: Selenium deficiency appears to limit antioxidant defense in obese individuals. This study evaluated the association between adiposity indices, selenium status, and oxidative stress in obese women. METHODS: This was a cross-sectional study involving 139 women who were divided into the following two groups: the case group (obese women, n = 63) and the control group (normal-weight women, n = 76). Plasma, erythrocyte, and urinary selenium levels were determined using inductively coupled plasma optical emission spectrometry. Body weight, height, waist circumference, hip circumference and neck circumference were measured. Body mass index, waist/height ratio, conicity index, body fat index, body adiposity index, body circularity index, and visceral adiposity index were calculated. Plasma levels of thiobarbituric acid reactive substances were determined. The erythrocyte glutathione peroxidase activity was determined using an automatic biochemical analyzer and Ransel kit. RESULTS: Obese women had selenium deficiency characterized by reduction in plasma and erythrocyte concentrations (P < .001). The urinary selenium excretion was higher in the case group compared to the control group (P < .001). Adiposity indices values and plasma concentrations of thiobarbituric acid reactive substances were significantly elevated in obese women (P < .001). There was a significant association between adiposity indices and selenium status (P < .001), and between erythrocyte selenium and erythrocyte glutathione peroxidase activity (P < .001). CONCLUSION: Obese women evaluated in the study have reduced plasma and erythrocyte concentrations of selenium and an increased urinary excretion of selenium. The correlation analysis reveals an association between intra-abdominal fat accumulation and selenium metabolism and oxidative stress.

Calcium and phosphorus parameters and their association with serum parathormone in chronic kidney patients on hemodialysis

ABSTRACT The objective of this study was to investigate the association between calcium and phosphorus parameters with serum parathormone concentrations in patients with Chronic Kidney Disease (CKD) undergoing hemodialysis. It is descriptive quantitative cross-sectional study. The sample was composed of 50 individuals distributed in: group with up to 5 years of hemodialysis and group with more than 5 years of hemodialysis. Food consumption was assessed using 24-hour dietary recall. Descriptive analysis of quantitative variables was presented as mean and standard deviation. Data analysis was performed using the SPSS program; Student "T" test, Fisher's exact test and Pearson's chi-square test were used, with significance level p <0.05. The groups presented adequate serum calcium concentrations and high concentrations of phosphorus and parathormone. Patients with more than 5 years of hemodialysis had a statistically higher serum parathormone level (p= 0.034); there was an association between longer hemodialysis time and higher serum phosphorus concentrations (p= 0.039). There was a moderate positive correlation between serum parathormone and phosphorus in the group with up to 5 years of hemodialysis (p= 0.012). It was concluded that the progression of CKD increases serum phosphorus and parathormone concentrations, reflecting the pathophysiological events and altered metabolic demand inherent to the pathology.

RESUMEN El objetivo de este trabajo fue investigar la asociación de los parámetros de calcio y fósforo con las concentraciones séricas de parathormona en pacientes con enfermedad renal crónica (ERC) en hemodiálisis. Se trata de un estudio descriptivo, cuantitativo y transversal. La muestra estuvo constituida por 50 individuos distribuidos en: grupo con hasta 5 años en hemodiálisis y grupo con más de 5 años en hemodiálisis. El consumo de alimentos se evaluó mediante el recordatorio de 24 horas. El análisis descriptivo de las variables cuantitativas se presentó como media y desviación estándar de la media. El análisis de los datos se realizó mediante el programa SPSS; Se utilizó la prueba "T" de Student, la prueba exacta de Fisher y la prueba de chi-cuadrado de Pearson, con un nivel de significancia de p <0.05. Los grupos mostraron concentraciones adecuadas de calcio sérico y altas concentraciones de fósforo y parathormona. Los pacientes con más de 5 años de hemodiálisis tenían un nivel de parathormona sérica estadísticamente más alto (p= 0,034); hubo una asociación entre un mayor tiempo de hemodiálisis y mayores concentraciones de fósforo sérico (p= 0,039). Hubo una correlación positiva moderada entre parathormona sérica y fósforo en el grupo con hasta 5 años de hemodiálisis (p= 0.012). Se concluyó que la progresión de la ERC aumenta las concentraciones séricas de fósforo y parathormona, reflejando los eventos fisiopatológicos y alteración de la demanda metabólica inherente a la patología.