Subscribe to RSS
DOI: 10.1055/s-0030-1268957
Elastic ageing in the cardiovascular system
Aims: Age-related arterial alterations affecting cells, matrix and biomolecules are the main culprit for initiation and progression of cardiovascular disease (CVD). Despite decreasing trends since around 1970 in industrialized countries, CVD is the leading cause of death in developing countries. The objective of this study is to gain further insights into the complex mechanism of elastic tissue ageing in human aortic blood vessels.
Methods and results: 180 human aortic tissue samples were collected from 118 patients (88 male, 30 female, age: 40–86 years) undergoing coronary artery bypass grafting. Overall extracellular matrix architecture was examined by multiphoton laser scanning microscopy (LSM) and histology. Matrix metalloproteinases –2 and –9, corresponding tissue inhibitors –1 and –2, as well as desmosine were determined. Messenger RNA (mRNA) levels of tropoelastin were assessed by quantitative RT- PCR. Age-related destruction of the vascular elastic laminas as well as a loss of inter-lamina cross-links were observed by LSM. These results were confirmed by histology indicating increasing inter-lamina gaps. We further found age-related reduced cell densities within the aortic media. There were no significant differences in matrix turnover or desmosine content. A steady decrease of tropoelastin mRNA (by about 50% per 10 years of age increase) was observed. Diabetes had no impact on elastogenesis.
Conclusions: Our findings indicate that ageing is accompanied by a destruction of the elastic vascular structure. However, tropoelastin expression analysis suggests that elastogenesis occurs throughout life with constantly decreasing levels.