Pentosidine

Background

AGEs are biochemicals formed continuously under normal circumstances, but more rapidly under a variety of stresses, especially oxidative stress and hyperglycemia. They serve as markers of stress and act as toxins themselves. Pentosidine is typical of the class, except that it fluoresces, which allows it to be seen and measured easily. Because it is well characterized, it is often studied to provide new insight into the biochemistry of AGE compounds in general.

Biochemistry

Derived from ribose, a pentose, pentosidine forms fluorescent cross-links between the arginine and lysine residues in collagen. It is formed in a reaction of the amino acids with the Maillard reaction products of ribose.{{cite journal

Although it is present only in trace concentrations among tissue proteins, it is useful for assessing cumulative damage to proteins—advanced glycation endproducts—by non-enzymatic browning reactions with carbohydrates.{{cite journal |author1=DG Dyer |author2=JA Blackledge |author3=SR Thorpe |author4=JW Baynes | title= Formation of pentosidine during nonenzymatic browning of proteins by glucose. Identification of glucose and other carbohydrates as possible precursors of pentosidine in vivo | access-date=2007-12-14 }}

Physiology

In vivo, AGEs form pentosidine through sugar fragmentation. In patients with diabetes mellitus type 2, pentosidine correlates with the presence and severity of diabetic complications.

References

References

1. (2004). "Simple non-invasive assessment of advanced glycation endproduct accumulation". Diabetologia.
2. (Oct 1992). "Pentosidine formation in skin correlates with severity of complications in individuals with long-standing IDDM.". Diabetes.