Author details

mainly of branched-chain and glucogenic amino acids. In this way, the study of the amino acid plasma profile in diabetic patients would be worthwhile, since it would reflect disturbances in protein and/or amino acid metabolism and consequently, in metabolic control of

Diabetic nephropathy is preceded by a window period, which might show different renal functional and/or structural disturbances, even in the early stages of the disease [7, 8]. In fact, the results obtained, in line with other researchers [17, 18], reveal significantly higher glomerular filtration in the diabetic group in comparison to the control group, and especially in those patients with a shorter period of disease and regardless of metabolic control of the disease. In addition, even when the whole diabetic group had normal blood pressure measurements, the existing correlation between diastolic blood pressure and the time of evolution of the disease suggests a situation of window period in diabetic nephropathy in this group of young diabetics, and highlights the importance of periodic blood pressure measurements in diabetics from the early stages of the disease. This allows for the beginning of a dietary and/or medical treatment earlier than was recommended until now [19]. However, it can be concluded that the structural integrity of the glomerulus in these diabetic patients would be relatively well preserved, since the urinary excretion of albumin was similar in

On another note, several researchers have noted a higher beta 2 microglobulin and lysosomal enzyme urinary excretion in diabetic patients in the absence of microalbuminuria, as a sign of functional disorder in the proximal tubule with no glomerular lesion, from the early stages of the disease [10, 11]. In this context, the study of amino acid urinary excretion in the diabetic could be of great interest, since different mechanisms of specific tubular reabsorption for different amino acids have been described on an experimental basis [20]. Hence, any tubular malfunction might condition significant qualitative and/or quantitative aminoaciduria, and therefore, it could have a potential clinical application in the early detection of tubular lesion

All the same, and according to the results obtained, urinary excretion of each single amino acid (except for isoleucine, aspartic acid, and taurine), as well as each amino acid groups analyzed were significantly lower in the diabetic group with respect to the control group. This may seem paradoxical; however, the difference observed in the relation glucogenic and total amino acid (G/T ratio) between both groups reveals that the lower amino acid urinary excretion in the diabetic would greatly be at the expense of glucogenic amino acids, probably because the glomerular filtration is also lower, as a consequence of a greater organic use of these amino acids in the endogenous synthesis of glucose. No correlation has been found between aminoaciduria and time of evolution, glomerular filtration, blood pressure, and

In sum, the study of amino acid urinary excretion in the young diabetic might have interest not only in the context of diabetic nephropathy, but also in the revealing of partial aspects of amino

acid metabolism, and probably, in the metabolic control of the disease.

the disease.

both groups.

and/or silent diabetic nephropathy.

metabolic control.

4.2. Urinary excretion

116 Diabetes and Its Complications

Teodoro Durá-Travé1,2\*, Fidel Gallinas-Victoriano2 , Ernesto Cortes-Castell<sup>3</sup> and Manuel Moya-Benavent<sup>3</sup>

\*Address all correspondence to: tduratra@cfnavarra.es


3 Department of Pediatrics, School of Medicine, University of "Miguel Hernández", Elche, Spain
