Glycosylated Proteins of Stratum Corneum, Nail and Hair in Diabetes Mellitus: Correlation with Cutaneous Manifestations

Abstract

Nonenzymatic glycosylation of protein may play some role in the development of diabetic complications. To study the association of nonenzymatically glycosylated protein in keratinized tissues with the prevalence of cutaneous manifestations frequently observed in diabetics, we measured furosine values of stratum corneum, nail and hair from 61 diabetics and assessed their cutaneous manifestations. The manifestation most frequently found in this study was 10 cases of pigmented pretibial patches. We did not detect significant correlations between the prevalence of any cutaneous manifestations and furosine values of any keratinized tissues. However, 11 of the 17 patients with yellow nail showed high nail furosine values. Our data suggest that nonenzymatically glycosylated protein levels in the keratinized tissues do not correlate with the prevalence of cutaneous manifestations in diabetics, but do not exclude a role in the formation of yellow nail.

Niacinamide

“…This leads to increased glycation and visibly more yellow appearance, described as "yellow skin syndrome" and "yellow nail syndrome." [19][20][21][22][23] There is thus potential for glycation to have a significant role in the aging-induced changes in skin appearance (eg, yellowing or sallowness). Niacinamide has been reported to have antiglycation effects, preventing this oxidative process likely via its role as a precursor to the endogenous antioxidant NAD(P)H. 24,25 For antiwrinkling, two mechanisms may apply.…”

Topical niacinamide reduces yellowing, wrinkling, red blotchiness, and hyperpigmented spots in aging facial skin1

“…An 'experiment of nature' that illustrates the impact of glycation on the appearance of skin is diabetes, where sugar levels are elevated. This leads to increased glycation and visibly more yellow appearance described as 'yellow skin syndrome' and 'yellow nail syndrome' [18][19][20][21][22]. There is thus potential for glycation to have a significant role in the normal aging-induced changes in skin appearance (e.g.…”

Effect of Non-Enzymatic Glycosylation and Heating on Browning of Human Stratum corneum and Nail

“…24]. We measured the extent of non-enzymatic glycosylation (furosine) in 17 diabetics with yellow nail, and they tended to have higher furosine values of the nails than 42 diabetics without yellow nail [7]. The growth rate of the nail plate depends on several factors, including site, age, sex, temperature, smoking and circulatory and hormonal abnormalities [25].…”

“…The extent of non-cnzy matic glycosylation was expressed asfurosinecontent [6], The prepara tion of standard furosine and the chromatogram of standard furosine have been previously described [7,8]. Each 5 mg of glycosylated sam ple was hydrolysed in 0.2 ml of 6 N HCI at 1()0°C for 18 h. The HCI was completely evaporated under vacuum, 0.3 ml of distilled water and 0.3 ml of chloroform were added to the residue.…”