Diabetic nephropathy (DN) is a multifactorial patholgy, characterized by the increased presence of albumin in urine. Currently, urinary albumin (uAlb) is a marker for glomerular damage mostly used for the diagnosis of DN; however, some reports in the literature showed that patients might exhibit histological signs of DN and normal uAlb. Markers of tubular damage have shown great ability to diagnose DN prior to onset of uAlb stages. Urinary markers can be adjusted by urinary creatinine (uCr), to compensate for the daily excretion rates; nevertheless, these standards are not fully established. Thus, the aim of this study was to evaluate the diagnostic ability of the markers of tubular damage NAG, GGT, NAP, KIM-1 and NGAL and the influence of the correction for uCr in DN. Glycemic control, lipid and hepatic enzyme profile as well urinary markers of glomerular and tubular damage were assessed in type 2 DM patients stratified into two groups regarding the existence of DN. The tubular markers evaluated in this study were higher in type 2 DM patients with DN compared to type 2 diabetes without DN for both markers expressed in absolute values or as a ratio to the uCr. When analyzing the areas under the curve (AUROC) obtained, we find that all markers, except for GGT expressed in absolute values, have the ability to identify the ND. NGAL and KIM-1, when expressed in absolute values had better diagnostic ability (AUROC> 0.9, sensitivity and specificity> 90%). NAG, GGT and NAP were when expressed in ratio had the best diagnostic capability, with AUROC equal to 0.683, 0.783 and 0.850, respectively. Stratifying patients into groups according to urinary albumin excretion (UEA), we found that NGAL and KIM-1 already showed increased levels in UEA range 10 - 30 mg/g cr. In addition to being, GGT showed an association with glomerular hyperfiltration Individuals in type 2 DM without nephropathy. Urinary tubular markers used in the study have potential value in diagnosis, especially NGAL and KIM-1 that showed the best diagnostic features, and are early markers of DN type 2 DM patients. / A nefropatia diabética (ND) é uma desordem multifatorial, caracterizada pelo aumento da presença da albumina na urina. A albumina urinária (uALb) é um marcador de dano glomerular mais utilizado para o diagnóstico da ND, no entanto, existem relatos na literatura que demonstraram que pacientes já apresentam sinais histológicos de ND mas com a uALb dentro da faixa de normalidade. Tem sido demonstrado uma grande capacidade dos marcadores de dano tubular em diagnosticar a ND em estágios anteriores ao aparecimento da uAlb. Os marcadores urinários na maioria são corrigidos pela creatinina urinária (uCr), para compensar as taxas de excreção diária, apesar de não haver padronização a respeito. Assim o objetivo deste estudo foi avavliar a capacidade diagnóstica dos marcadores de dano tubular NAG (N-β-acetil-glucosaminidase), GGT (Gama-glutamiltransferase), NAP (Protein nonalbumin), KIM-1(Kidney molecule injury 1) e NGAL (Neutrophil gelatinase associated lipocalin) em relação à ND e verificar a influência da correção pela uCr nas características diagnósticas dos mesmos em pacientes com DM tipo 2. Foram mensurados indicadores do controle glicêmico, perfil lipídico e hepático, marcadores urinários de dano glomerular e tubular nos pacientes com DM do tipo 2 estratificados em dois grupos, com e sem ND. Observou-se que os marcadores tubulares avaliados foram significativamente mais elevados nos pacientes com DM tipo 2 com ND em relação ao grupo sem ND, tanto para os marcadores expressos em valores absolutos ou na forma de razão com a uCr. Quando foram analisadas as áreas sob a curva (AUROC) obtidas, verificamos que todos os marcadores, com exceção de GGT expressa em valores absolutos, tiveram a capacidade de identificar a ND. NGAL e KIM-1, quando expressos em valores absolutos tiveram a melhor capacidade diagnóstica (AUROC > 0,9, sensibilidade e especificidade > 90%). NAG, GGT e NAP quando expressos na razão tiveram a melhor capacidade de diagnóstico, com AUROC igual a 0,683, 0,783 e 0,850, respectivamente. Estratificando os pacientes em grupos de acordo com a excreção urinária de albumina (EUA), verificamos que a NGAL e o KIM-1 já apresentaram níveis aumentados no intervalo EUA 10 - 30 mg/g cr. Além disso, a GGT demonstrou estar associada com a hiperfiltração glomerular em indivíduos DM tipo 2 sem nefropatia. NGAL e KIM-1 foram os marcadores tubulares urinários que demonstraram as melhores características diagnósticas, além de ser marcadores precoces da ND em pacientes DM tipo 2.

The main focus of our research was to compare changes in ion excretion in urine, osmolality, indicators of exercise-induced proteinuria and tubular markers before and after dynamic exercise on a bicycle ergometer. The test sample consisted of 7 healthy, physically active women aged 27.4 years ( σ = 3.82 ). For dynamic exercise we uniformly set parameters 65 % VO2max and duration of load in 50 minutes. We compared the laboratory results of urine samples taken just before the exercise with urinary samples that we have collected immediately after exercise. The results of our measurements showed a significant changes in exercise-induced urinary sodium ions, creatinine and phosphorus. Statistically insignificant changes excretion was found between markers: chlorine, urine, osmolality, and N-acetyl-beta- d-glucosaminidase. These markers, however, show a trend the significance. Statistically insignificant changes after exercise have shown excretion of urinary markers: potassium, gelatinase-associated lipocalin, neutrophil microalbuminuria and alpha-1-microglobulin. Tubular markers of kidney damage after exercise is not at the reference values, that would indicate the tubular kidney damage.