Evidence that V+ fibronectin, GFAP and S100 beta mRNAs are increased in the hippocampus of aged rats.
In the present study, using RNA gel-blot analysis, we characterized the developmental changes in the prevalence of mRNA coding for fibronectin (FN), glial fibrillary acidic protein (GFAP), neurotrophic protein S100 beta, and beta-actin mRNA in rat hippocampus and forebrain from 1 to 720 days of age. We found that the FN and mRNA containing the V segment (FN-V) was relatively abundant at early postnatal stages, but very few transcripts were detected in adult rats. However, the hybridization signal for the juvenile FN-V mRNA was up to approximately 8-fold increased in some but not all 24-versus 6-month-old rats. Also, GFAP and S100 beta transcripts were faintly expressed at an early developmental stage, then the level of expression steadily increased starting with day 21. The greatest increase averages approximately 1.8-fold for GFAP in 24-month-old rats, and approximately 1.5-fold for S100 beta in 15-month-old versus 6-month-old rats. As all these messages are localized primarily in astrocytes, we conclude that (a) astrocyte might play an active role in aging hippocampus and (b) an increase in S100 beta and GFAP mRNA expression may precede that for FN-V mRNA expression in a hypothetical pathway of molecular events underlying neurodegeneration in the hippocampus of old rats. We also note the considerable variability among the 24-month-old rats, suggesting that aging is an individual process.
Wagner
A P
AP
Institute of Gerontology, University of Erlangen-Nuremberg, Germany.
Reck
G
G
Platt
D
D
D000199:Actins / Q000096:biosynthesis / Q000235:genetics; D000375:Aging / Q000378:metabolism*; D017398:Alternative Splicing; D000818:Animals; D001253:Astrocytes / Q000378:metabolism; D015152:Blotting, Northern; D002135:Calcium-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D005353:Fibronectins / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression; D005904:Glial Fibrillary Acidic Protein / Q000096:biosynthesis* / Q000235:genetics; D006624:Hippocampus / Q000378:metabolism*; D008297:Male; D009414:Nerve Growth Factors; D016548:Prosencephalon / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D011916:Rats, Inbred F344; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000096:biosynthesis* / Q000235:genetics; D013047:Specific Pathogen-Free Organisms; D014158:Transcription, Genetic
D000199:Actins; D002135:Calcium-Binding Proteins; D005353:Fibronectins; D005904:Glial Fibrillary Acidic Protein; D009414:Nerve Growth Factors; D012333:RNA, Messenger; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins