Restriction of sulfur-containing amino acids alters claudin composition and improves tight junction barrier function
| Autor: | James M Mullin, Mary Carmen Valenzano, Sonja M. Skrovanek |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Aging
Swine Physiology Blotting Western Fluorescent Antibody Technique Biology Cell junction Tight Junctions Kidney Tubules Proximal chemistry.chemical_compound Occludin Physiology (medical) Animals Amino Acids Claudin Barrier function chemistry.chemical_classification Methionine Tight junction Membrane Proteins Epithelial Cells DNA Culture Media Diet Amino acid Electrophysiology Amino Acids Sulfur chemistry Biochemistry Biophysics LLC-PK1 Cells RNA Composition (visual arts) Homeostasis |
| Zdroj: | American Journal of Physiology-Regulatory, Integrative and Comparative Physiology. 293:R1046-R1055 |
| ISSN: | 1522-1490 0363-6119 |
| Popis: | Restriction of sulfur-containing amino acids (SCAA) has been shown to elicit a similar increase in life span and decrease in age-related morbidity as caloric restriction. The singular importance of epithelial barrier function in both physiological homeostasis and prevention of inflammation raised the issue of examining the effect of SCAA restriction on epithelial tight junction structure and permeability. Using a well-described in vitro, epithelial model, the LLC-PK1renal epithelial cell line, we studied the effects of SCAA restriction in culture medium. Reduction of methionine by 90%, cysteine by 50%, and total elimination of cystine resulted in dramatically lower intracellular pools of these amino acids and their metabolite, taurine, but the intracellular pools of the non-SCAA were all elevated. Cell growth and differentiation were maintained, and both confluent cell density and transepithelial short circuit current were unaffected. Certain tight junctional proteins, such as occludin and claudins-1 and -2 were not altered. However, claudins-3 and -7 were significantly decreased in abundance, whereas claudins-4 and -5 were markedly increased in abundance. The functional result of these structural changes was improved barrier function, as evidenced by increased transepithelial electrical resistance and decreased transepithelial (paracellular) diffusion of d-mannitol. |
| Databáze: | OpenAIRE |
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