The Effect of Diabetes on Leucine and Fucose Incorporation into PNS Myelin Proteins

Summary

Peripheral neuropathy is a common complication associated with diabetes mellitus. Segmental demyelination and other pathological changes frequently accompany loss of sensory and motor nerve function. Morphological changes seen in diabetic nerve myelin may be a result of altered Schwann cell metabolism under hyperglycemic conditions.

Using both alloxan and streptozotocin - induced diabetic rats of 2, 4 and 8 months duration of diabetes, metabolic changes in isolated sciatic nerve myelin were assessed using a double-label in vitro incubation system. Incorporation of ³H-fucose and 1-¹⁴C-leucine into myelin was determined per microgram protein. Specific activities of incorporated protein precursors were compared as a ratio of fucose to leucine. Using the Newman-Kuels test for multiple comparisons, statistically significant increases were found in the incorporation ratios of diabetic rats at 2 and 4 months of diabetes when tested against agematched controls.

Key-Words:

Streptozotocin Diabetes - Alloxan Diabetes - Protein Incorporation - Glycoprotein Incorporation - Myelin