Elastin changes

Light N, Meyrick Thomas RH, Stephens A, Kirby JD, Fryer PR, Avery NC. Collagen and elastin changes in D-penicUlamine-induced pseudoxanthoma elasticum-like skin. Br J Dermatol 1986 114(3) 381-8. 

Elastin is a protein also found in connective tissue that imparts an ability for these tissues to undergo large shape and size changes without permanent damage to the... 

Urry, W. D., Krivacia, J. R., Haider, J. Calcium ion effects of notable change in elastin conformation by interacting with neutral sites. Biochem. Biophys. Res. Commun. 43, 6 (1971)... 

Various natural, chemically modified and mixtures of flavonoids are widely used therapeutically as venous protective or venotonic drugs in chronic venous insufficiency and haemorrhoidal attacks. Flavonoids have been found to inhibit increased vessel wall permeability, fluid changes in the capillary bed and diffusion of plasma proteins. In addition, they may exert a protective effect on the perivascular tissues due to their antihyaluronidase effect and the inhibition of lysine oxidase (producing crosslinks in collagen and elastin) and lysosomal hydrolases (degrade glycosamines). All these effects may account for the venotonic effects of these drugs [5]. However, the venous effects of flavonoids are out of the scope of the present review. 

Urry, D. W., Starcher, B., and Partridge, S. M. (1969). Coacervation of solubilized elastin effects a notable conformational change. Nature 222, 795-796. 

Although nonenzymatic glycosylation may affect practically every protein in vivo, it is likely that nonenzymatic browning will occur only in proteins that have a slow turnover or none at all, such as lens crystallins, collagen, elastin and proteoglycans. In some tissues, these proteins are, in effect, "stored" for a lifetime and undergo some characteristic changes, many of which have been observed in stored and processed foodstuffs (Table II). 

The reaction of the arteriolar wall to changes in the blood pressure is considered to consist of a passive, elastic component in parallel with an active, muscular response. The elastic component is determined by the properties of the connective tissue, which consists mostly of collagen and elastin. The relation between strain e and elastic stress ae for homogeneous soft tissue may be described as [18] ... 

The mechanical properties of polymer chains that do not exhibit interactions between the side chains and the backbone, or one part of the backbone and another part of the backbone, are related to the number of available conformations and hence the chain entropy. As we discuss later, the stiffness of a polymer chain that does not exhibit bonding with other parts of the chain is related to the change in the number of available conformations. It turns out this refers to random chain polymers of which elastin, poly(ethylene) at high temperatures, and natural rubber are discussed in this text. As we stretch a polymeric chain we reduce the number... 

Although true randomly coiled chains don t exist in vertebrate tissues, because these structures are susceptible to rapid hydrolysis, sequences that are found in proteins such as elastin are believed to form rubberlike regions that store energy entropically by changing conformational angles during mechanical deformation. 

This review focuses upon the post-translational modification and chemical changes that occur in elastin. Outlined are the steps currently recognized as important in the assembly of pro-fibrillar elastin subunits into mature fibers. Descriptions of some of the proposed mechanisms that appear important to the process are also presented. It will be emphasized that from the standpoint of protein deterioration, elastin is a very novel protein. Under normal circumstances, the final product of elastin metabolism, the elastin fiber does not undergo degradation that is easily measured. Unlike the metabolism of many other proteins, deterioration or degradation is most evident biochemically in the initial stages of synthesis rather than as a consequence of maturation. Since the presence of crosslinks is an essential component of mature elastin, a section of this review also addresses important features of crosslink formation. 

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