Abstract
Lipoperoxides have received considerable attention as a causal factor in aging, atherosclerosis and other degenerative changes. Elevated levels of plasma lipoperoxides have been reported in diabetes mellitus by several researchers. In particular, diabetics with vascular complications tend to show higher plasma lipoperoxide levels. In the present study, the plasma lipoperoxide levels in 136 diabetics and 171 normal subjects were determined and the relationship between the plasma lipoperoxide levels and diabetic angiopathy was tested.
1) The plasma lipoperoxide levels were found to increase with age up to 50 years old in diabetics and normal subjects, and no difference between the groups was observed under 50 years of age.
2) The lipoperoxide levels in the plasma of diabetic patients over 50 years old with either hyperlipidemia or ischemic heart disease, were significantly higher than those in cases without the complications.
3) In female diabetic patients over 50 years old with calcification of the aorta, the lipoperoxide levels were significantly higher than those in cases without this complication.
These results indicate that diabetic patients with macroangiopathy tend to show higher plasma lipoperoxide levels. Vascular complications play an important role in the prognosis of diabetes. Prostacyclin has the most potent antiaggregating activity on platelets. Decreased prostacyclin levels have recently been reported in the arterial walls of diabetic patients and were regarded as a possible cause of the diabetic angiopathy. On the other hand, the inhibitory effect of lipoperoxides on prostacyclin synthesis in the vessel wall has been demonstrated. In this context, the increased levels of plasma lipoperoxides in diabetics are of particular interest.
