Lactase synthesis is pretranslationally regulated in protein-deficient pigs fed a protein-sufficient diet

Mary A. Dudley, Patricia A. Schoknecht, Alden W. Dudley, Lan Jiang, Ronaldo P. Ferraris, Judy N. Rosenberger, Joseph F. Henry, Peter J. Reeds

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

The in vivo effects of protein malnutrition and protein rehabilitation on lactase phlorizin hydrolase (LPH) synthesis were examined. Five-day-old pigs were fed isocaloric diets containing 10% (deficient, n = 12) or 24% (sufficient, n = 12) protein. After 4 wk, one-half of the animals in each dietary group were infused intravenously with [13C1]leucine for 6 h, and the jejunum was analyzed for enzyme activity, mRNA abundance, and LPH polypeptide isotopic enrichment. The remaining animals were fed the protein-sufficient diet for 1 wk, and the jejunum was analyzed. Jejunal mass and lactase enzyme activity per jejunum were significantly lower in protein-deficient vs. control animals but returned to normal with rehabilitation. Protein malnutrition did not affect LPH mRNA abundance relative to elongation factor-1α, but rehabilitation resulted in a significant increase in LPH mRNA relative abundance. Protein malnutrition significantly lowered the LPH fractional synthesis rate (FSR; %/day), whereas the FSR of LPH in rehabilitated and control animals was similar. These results suggest that protein malnutrition decreases LPH synthesis by altering posttranslational events, whereas the jejunum responds to rehabilitation by increasing LPH mRNA relative abundance, suggesting pretranslational regulation.

Original languageEnglish (US)
Pages (from-to)G621-G628
JournalAmerican Journal of Physiology - Gastrointestinal and Liver Physiology
Volume280
Issue number4 43-4
DOIs
StatePublished - Apr 2001

All Science Journal Classification (ASJC) codes

  • Physiology
  • Hepatology
  • Gastroenterology
  • Physiology (medical)

Keywords

  • Fractional and total synthesis rates
  • Gas chromatography-mass spectroscopy
  • Messenger ribonucleic acid
  • Small intestine

Fingerprint

Dive into the research topics of 'Lactase synthesis is pretranslationally regulated in protein-deficient pigs fed a protein-sufficient diet'. Together they form a unique fingerprint.

Cite this