Age-dependent expression of XXXX -related genes and collagen deposition in the @entity35 myocardium.

@entity35 @entity82 @entity1810 @entity19255
OBJECTIVES: We sought to characterize the evolution, during maturational growth and early ageing, of the messenger abundance of four genes involved in cardiac @entity82 regulation (procollagens alpha2(I) and alpha1(III), transforming growth factors beta1, and beta3) and corroborate it with the alterations in collagen deposition in cardiac interstitium and around coronary arteries. METHODS: Messenger RNA was quantified in LV and RV of 2-, 6-, 12- and 19-month-old male @entity35 (n = 5 per group) with Northern blot analysis. Collagen deposition was quantified with a semi-automated image analyser on Sirius red-stained sections of LV tissue. RESULTS: There was an age-related monotonous decrease of procollagen type I (COL-I) transcript abundance in LV (p < 0.001) but not in RV. Procollagen type III (COL-III) expression decreased rapidly during maturational growth, both in LV and RV. On the other hand, collagen deposition in myocardial interstitium and around coronary arteries was slightly augmented during the maturational period of life (2-12 months), but with a higher rate during early ageing (up to 19 months). This was not accompanied by a significant thickening of the wall of coronary arteries. @entity1810 , ( @entity1810 ) and @entity19255 ( @entity19255 ) transcript abundance showed no major variations during ageing. CONCLUSIONS: These results reflect a striking ventricular difference regarding the age-dependent expression of COL-I. The expression of @entity1810 (s), pleiotropic factors known to influence collagen pathway at different levels, does not seem to be profoundly altered during ageing. The discrepancy between protein and COL-I and COL-III mRNA levels indicates differences in age-related mRNA stability and/or regulation of collagen translation.
