The Blood Vessels

By Author: asdas
Total Articles: 105
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As people age, their cells become less efficient and less able to replace damaged components. At the same time their tissues stiffen. For example the lungs and the heart muscle ex-and less successfully, the blood vessels become increasingly rigid, and the ligaments and tendons tighten.
Few investigators would attribute such diverse effects to a single cause. Nevertheless, researchers have discovered that a process long known to discolor and toughen foods may also contribute to age-related impairment of both cells and tissues. That process is no enzymatic lycosylation, whereby glucose becomes attached to proteins without the aid of enzymes. When enzymes attach glucose to proteins (enzymatic glycosylation), they do so at a specific site on a specific protein molecule for a specific purpose. In contrast, the no enzymatic process adds glucose haphazardly to any of several sites along any available peptide chain within a protein molecule.

This no enzymatic glycosylation of certain proteins has been understood by food chemists or decades, although few biologists recognized until recently that the same steps could take) ...
... lace in the body. No enzymatic glycosylation begins when an aldehyde group (CHO) of glucose and an amino group (NH2 )of a protein are attracted to each other. The molecules combine, forming what is called a Schiff base within the protein. This combination is unstable and prickly rearranges itself into a stable, but still reversible, substance known as an Amador conduct.

If a given protein persists in the body for months or years, some of its Amador products slowly dehydrate and rearrange themselves yet again, into new glucose-derived structures; rhesus can combine with various kinds of molecules to form irreversible structures named Advanced Glycosylation End products (AGE's). Most AGE's are yellowish brown and fluorescent and have specific spectrographic properties. More important for the body, many are also able 0 cross-link adjacent proteins, particularly ones that give structure to tissues and organs. Although no one has yet satisfactorily described the origin of all such bridges between proteins, many investigators agree that extensive cross-linking of proteins probably contributes to the stiffening and loss of elasticity characteristic of aging tissues.

In an attempt to link this process with the development of cataracts (the browning and clouding of the lens of the eye as people age), researchers studied the effect of glucose on solutions of purified crystalline, the major protein in the lens of the eye. Glucose-free solutions remained clear but solutions with glucose caused the proteins to form clusters, suggesting that the molecules had become cross-linked. The clusters diffracted light, making the solution opaque. The researchers also discovered that the pigmented cross-links in human cataracts have the brownish color and fluorescence characteristic of AGE's. These data suggest that no enzymatic glycosylation of lens crystalline may contribute to cataract formation.