Age-Related Changes in Elastic Fibers of Human Heart

Abstract

The effects of age on the human heart elastic fibers were studied by light and electron microscopy. Studies were done on 15 hearts from male subjects 42 days to 87 years of age. Using specific staining procedures, the length of elastic fibers was determined by morphometry in the parenchyma of right and left ventricles. These studies suggest that the length of elastic fibers per unit heart volume is present early in life, possibly at birth, and thereafter remains constant until adulthood. Average fiber length increases significantly beyond the third decade of life which can be interpreted as a continuous formation of new fibers and a continuous apposition of elastic-type material to these fibers. Electron microscopy confirmed the presence of mature elastic fibers at birth, since they contained amorphous substance (elastin) surrounded by numerous microfibrils. In the adult hearts, the amount of amorphous substance has increased and the number of microfibrils has decreased. With advancing age the amorphous substance forms areas of rarefaction and the microfibrils have disappeared. Whether or not such morphometric modifications could influence the elastic properties of the ventricular myocardium requires further study.

A Morphological Study of Age Changes in Adult Human Auricular Cartilage With Special Emphasis on Elastic Fibers

“…Elastic fiber length per unit volume in the human heart increases from adulthood to old age. 9 In a recent study on human dermis, the relative volume density of elastic fibers in males is found to increase after 20 years, but those in females display a decreasing trend. 18 The volume of elastic fibers appears to differ depending on organ, gender, and age.…”

“…Elastic fibers in the human heart change structure with age. 9 In addition, because elastic fibers in the dermis change with age, aged human skin appears loose and sagging with reduced resilience and elasticity compared with young skin. 10 It is of great interest to determine whether elastic fibers in the auricular cartilage undergo structural changes with age similar to those in the dermis.…”

Mesenchymal stem cell-derived inflammatory fibroblasts mediate interstitial fibrosis in the aging heart

“…In the heart, ECM consists predominantly of collagen type I (Col1), and (to a much smaller degree), collagen type III [11], fibronectin [12, 13], laminin [13], and elastic fibers [14]. EMC synthesis is tightly regulated and any disturbance may have serious consequences; in the normal healthy heart collagen content is low [15] but its synthesis is upregulated in response to various stimuli such as mechanical stretch [16], ischemia [17], pressure overload [13] or aging [15].…”

Insuficiência cardíaca diastólica no idoso

“…Quanto às fibras elásticas propriamente ditas situam-se entre os miócitos, no meio da rede de fibras oxitalânicas e elaunínicas. Essa disposição permitiria que o sistema elástico funcionasse de maneira bifásica, através de componentes (fibras elásticas) que favoreceriam o alongamento das fibras musculares na diástole, acumulando tensão e com componentes (fibras oxitalânicas e elaunínicas) que coadjuvariam as fibras colágenas, limitando a distensão da musculatura 35 ( fig. 2).…”

“…2). Durante o envelhecimento, verifica-se aumento da densidade das fibras, acompanhado de alterações morfológicas, observando-se que as fibras elásticas tornam-se mais espessas e com contornos irregulares 35 .…”