Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1993-9-8
pubmed:abstractText
The current investigation examines the changes in the expression of pepsinogen C and cathepsin D and E genes in the gastric mucosa during aging and following physiological stimuli of fasting and refeeding. Northern blot analysis of gastric mucosal RNA, isolated from overnight fasted 6-, 12-, and 24-month-old male Fischer 344 rats, revealed that although steady-state mRNA levels of each of these protease remained essentially unchanged between 6 and 12 months of age, in 24-month-old rats the levels were decreased by about 60%, when compared with their younger counterparts. Interestingly, the relative concentration of beta-actin mRNA--but not 18s rRNA--in 12- and 24-month-old rats was also decreased by 23% and 37%, respectively, when compared with 6-month-old animals. In the next set of experiments, groups of young (3 month) and aged (24 month) rats were either fed throughout (controls) or fasted for 48 h and then fed for 6 h and 24 h. Gastric mucosal RNA from each group was assayed for steady-state mRNA levels of pepsinogen C and cathepsin D. Results showed that whereas in young rats fasting decreased pepsinogen C and cathepsin D mRNAs by 80-85%, in aged rats only pepsinogen mRNA was significantly decreased (45%), when compared with the corresponding initial fed controls. In both age groups, refeeding increased pepsinogen C mRNA concentration essentially to the respective initial fed levels. In contrast, cathepsin D mRNA levels in the gastric mucosa of aged rats was affected neither by fasting nor by refeeding. Our current data show that aging not only diminishes the expression of protease genes in the gastric mucosa, but also the expression of one of its structural genes, beta-actin. In addition, responsiveness of these protease genes to the physiological stimuli of fasting and refeeding is also attenuated by aging. We postulate that these age-related changes may in part be due to diminished differentiation of gastric mucosal cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0531-5565
pubmed:author
pubmed:issnType
Print
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
249-58
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:articleTitle
Expression of protease genes in the gastric mucosa during aging.
pubmed:affiliation
VA Medical Center, Education Service (14A), Allen Park, Michigan 48101.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.