Urinary Proteomics Analysis of a High Salt Diet

Abstract

The American Heart Association recommends that healthy adults should eat < 2.4g of sodium a day. Currently, the average American eats 9–12 g of salt a day. The kidney is the major organ in the body that is responsible for maintaining sodium and water homeostasis in response to the high salt diet. In order to excrete the excess sodium, there is an increase in the renal transport and regulatory proteins. The purpose of this study was to determine if qualitative alterations occurs in urinary proteins in response to a high salt diet. To achieve this goal a portion of 24‐hr urine samples from C57BL10 mice fed either a normal salt (0.3%NaCl) or a high salt diet (8.0%NaCl) for seven days were used in this study. The urine was treated with protease inhibitors and the total protein concentration was determined by a Bradford assay with BSA as the standard. 5.3 ìg of total protein from each sample were analyzed on a 12% SDS‐PAGE. Preliminary analysis revealed that there are more visible bands in the urine of animals fed a chronic HS diet than in urine of animals fed a NS intake. In addition, some bands were present or absent in the HS urine when compared with the protein bands in the NS urine. Although further evaluation is needed, this data suggest that alterations in urinary protein excretion do occur in response to a chronic HS intake. The analysis of urinary proteins could provide a noninvasive method of evaluating physiological.