Furosine derived from fructose-lysine, which was formed by binding the lysine residues of hair protein, was measured and used as an indicator of glycation.In the present study, taking advantage of the characteristic that hair is continuous, we found that the extent of glycation of hair which corresponded in length to one year's growth correlated significantly with the mean level of fasting plasma glucose and HbAi c from four previous determinations.
Furthermore, we classified the pattern of onset of diabetes into the following three types according to the ascending gradient of hair furosine levels at the time of onset of diabetes ; rapidly rising type, gradually rising type, long term gradually rising type.Seventy-eight % of rapidly type-diabetics were treated with insulin and 55% of long term gradually rising type-diabetics were treated by diet only in a survey of therapeutic modalities given at least 6 months after onset.
These results suggest that measurement of the glycation in long hair may be useful as an indicator of long-term control of blood glucose level, and moreover, that the measurement of hair glycation in patients who appear to have suddenly developed diabetes may allow us to predict future diabetic treatment by determining the type of onset of diabetes in the early stage of treatment.

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Probucol is a hypocholesterolemic agent which inhibits the oxidation of low-density lipoprotein in vitro.The present study was designed to examine the protective action of probucol against pancreatic beta-cell damage by multiple low-dose streptozotocin (STZ) injection. STZ (40 mg/kg, ip) was intraperitoneally injected for 5 consecutive days.The degree of hyperglycemia at 7, 14 and 17 days after STZ administration was attenuated by probucol administration.The basal insulin level was increased in the mice fed the 1% probucol containing diet at Day 14.The percentage of incubated splenic cells, positive for Thy 1.2, was significantly decreased in the mice fed the 1% probucol containing diet.However, there were no effects of probucol on the populations of splenic cells positive for Lyt 2 or L3/T4.Serum probucol concentrations were maintained at the same levels as those obtained by clinical study.
The data obtained herein suggest that probucol has a protective effect against pancreatic insulitis due to multiple low-dose STZ administrations.Probucol may be a candidate for clinical application, as an agent which blocks the development of insulin-dependent diabetes.

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The usefulness of skin biopsy as a morphological method of assessing diabetic neuropathy was evaluated.The density of unmyelinated nerve fibers in the upper dermis was significantly lower (p<0.01, 142± 75 vs 310+186/mm2) and axonal vacuolation (p<0.05, 21± 21 vs 7± 16%) and Schwann cell clusters devoid of axons (SCCDA)(p<0.01, 22± 27vs1±3%) were more frequently found in diabetic patients (n=29) than in age-matched control subjects (n=11). In diabetic patients, the frequency of basement membrane multiplication of Schwann cells was higher in patients with abnormal sensation in their limbs than in patients without it (p<0.05, 61±18 vs 40±24%).Patients with pain in their limbs showed a higher frequency of the basement membrane multiplication (p<0.05, 67±19 vs 45±24%) and SCCDA (p<0.05, 57±34 vs 17±19%) than patients without pain.
In view of the safety and convenience of skin biopsy these results might suggest the usefulness of this procedure for pathological evaluation of diabetic neuropathy.

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The peroxidase-dependent degradation of H202 in human umbilical vein endothelial cells (ECs) cultured in the presence of 16.5 mM and 33 mM glucose was significantly impaired, by 12%(p< 0.01) and 36%(p<0.001), respectively, as compared to the 5.5 mM glucose control. Furthermore, non-metabolizable L-glucose and D-raffinose had no effect on the degradation of H202 in cultured ECs.The high glucose effect was completely reversed in the presence of 1, uM SNK 860, an aldose reductase inhibitor.In contrast, there was no effect of high glucose on the catalase-dependent degradation of H₂0₂ in ECs. The EC number per dish decreased by 11%(p<0.05) and H₂0₂-induced ⁵¹Cr release from ECs increased by 50%, as compared with the control values, after the cells were cultured for 4-5 days in 33 mM glucose media.These results indicate that impairment of peroxidase-dependent degradation of H₂0₂ in ECs cultured in high glucose media, is associated with activation of the sorbitol pathway and that ECs consequently become more susceptible to H202-induced cell injury

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