Acute and chronic effect of dietary phosphorus restriction on protein expression in young rat renal proximal tubules

Pik Yuen Cheung, Wan Ping Lai, Hoi Yan Lau, Chun Lap Samuel Lo, Man Sau Wong

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

Renal proximal tubules play a vital role in phosphorus (P) homeostasis. It is well known that dietary P restriction up-regulates the activities of 25-hydroxyvitamin D3-1 α-hydroxylase (1-OHase), an enzyme that is involved in activation of vitamin D and thereby maintaining P balance. However, the mechanism involved in such regulation is not known. In the present study, we aim to identify proteins that might be involved in the renal adaptation to dietary P restriction using a proteomic approach. Renal proximal tubules were harvested from young rats fed either normal P diet or low P diet (LPD) for 1 to 7 days. Western blotting analysis of 1 -OHase and signaling proteins in insulin-like growth factor I axis indicated an increase in expression of these proteins upon dietary P restriction. Using two-dimensional electrophoresis, we found that LPD reduced the total number of protein species expressed in renal proximal tubules. Differentially expressed proteins were analyzed and located using the software Melanie III, and their identities were found using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Our results showed that β-actin, γ-actin, major urinary protein, phosphatidylinositol transfer protein β isoform, and G1/S-specific cyclin D3 are up-regulated and nonspecific lipid transfer protein is down-regulated by LPD.
Original languageEnglish
Pages (from-to)1211-1219
Number of pages9
JournalProteomics
Volume2
Issue number9
DOIs
Publication statusPublished - 1 Sep 2002

Keywords

  • Insulin-like growth facor I axis
  • Phosphorus restriction
  • Rat renal proximal tubules
  • Two-dimensional gel electrophoresis

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology

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