Abstract
This study reports some observations concerning the impaired glucose tolerance (IGT) and the diabetes mellitus (DM) which are frequently associated with Werner's syndrome.
These three patients all exhibited characteristic clinical symptoms and signs of Werner's syndrome since at 20-30 years of age, and they also had siblings with the same disease in their families. Oral glucose tolerance tests(75g O-GTT) showed the IGT pattern in two cases and DM pattern in one case. Plasma IRI levels after the 75g glucose load showed high responses in all three cases. Further more, two cases gave high IRI values already at the fasting state(pre-loading). Then the urinary excretion of C-peptide (CPR) showed also high values.
Although abnormal glucose tolerance were mild in these three cases, but hyperexcretion of urinary CPR, hyperinsulinemia and hyperresponsiveness of IRI after glucose loads were recognized.
Regarding the etiology of glucose intolerance accompanied by hyperinsulinemia, in one case we evaluated that insulin binding capacity in the erythrocytes of the patient was normal: otherwise, the pyruvate dehydrogenase activity in the lymphocytes showed a remarkably low rate.
Concerning the abnormal glucose tolerance associated with Werner's syndrome, it was speculated that this phenomenon reflects partially a defect of post-receptor mechanism.
