Prepubertal onset of diabetes prevents expression of renal cortical connective tissue growth factor.
Puberty unmasks or accelerates the nephropathy of diabetes mellitus (DM). We performed focused microarray analysis to test the hypothesis that one or more genes in the transforming growth factor beta (TGF-beta) signaling system would be differentially regulated in male rats depending on their age at onset of DM. Littermates were started on the 6-week protocol at 4 weeks or 14 weeks of age. Renal cortical RNA was isolated and analyzed using gene chips with more than 30,000 transcripts. Age-specific effects of DM were demonstrated for 1,760 transcripts. Analysis then focused on 89 genes involved in the TGF-beta signaling pathway. Three of these genes showed age-dependent responses to DM, confirmed by quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Connective tissue growth factor (CTGF) mRNA and protein were both increased approximately 30% in the renal cortex 6 weeks after adult-onset DM, with no alteration in either parameter after juvenile onset. Follistatin and avian myelocytomatosis viral oncogene homolog mRNA both showed a similar age-related pattern of response to DM, but protein levels did not parallel mRNA for either of these gene products. Given the known roles of CTGF in progressive nephropathies, it is an attractive candidate to explain pubertal acceleration or unmasking of the kidney disease of diabetes.
Langer
William J
WJ
Department of Pediatrics, University of Nebraska Medical Center, Omaha, NE, USA.
Devish
Kay
K
Carmines
Pamela K
PK
Lane
Pascale H
PH
D000375:Aging / Q000502:physiology*; D000818:Animals; D055513:Connective Tissue Growth Factor; D003921:Diabetes Mellitus, Experimental / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D019085:Fluorescent Antibody Technique, Direct; D038681:Follistatin / Q000235:genetics / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D020570:Genes, myb / Q000235:genetics; D017874:Immediate-Early Proteins / Q000235:genetics / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism*; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012741:Sexual Maturation / Q000502:physiology*; D015398:Signal Transduction; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism*
C526316:CCN2 protein, rat; D038681:Follistatin; D017874:Immediate-Early Proteins; D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D055513:Connective Tissue Growth Factor