Decrease in Myelin Content of Rabbit Sciatic Nerve with Aging and Diabetes

Abstract

Previous studies of the amount of peripheral nerve myelin have been based on histologic examination. In this study, myelin content was measured directly after quantitative isolation from sciatic nerve. There was a decrease in the amount of myelin beginning at nine months, the time of maximal myelin content in normal rabbits, and beginning at six months, the amount was decreased in diabetic as compared with control animals. Composition of myelin isolated from young (age three to four months) and old (age nine to thirteen months) rabbit sciatic nerves was also determined and is similar to that of other species. Although the composition was not affected by diabetes, with aging there was a significant decrease in the amount of cholesterol and an increase in glycolipid.

Differential hypertrophy and atrophy among all types of cutaneous innervation in the glabrous skin of the monkey hand during aging and naturally occurring type 2 diabetes

“…Consistent with this possibility, the presumptive Aδ fibers that express NF may normally be relatively stable and appear to preferentially remain through aging and diabetes (Fernyhough et al,1999). In the monkeys with prolonged diabetes, even the Aδ fibers expressed GAP43 and became reduced compared to those in nondiabetics, indicating that they may have become unstable, perhaps due to deterioration of their myelin sheaths (Bischoff,1973; Spritz et al,1975; Bestetti et al,1981; Sima et al,1988). One reason for the reduced capacity to regenerate may be a thickening of the basement membrane possibly due to a nonenzymatic glycation of basement membrane proteins (Tarsio et al,1985; King,2001).…”

The effects of dietary treatment with essential fatty acids on sciatic nerve conduction and activity of the Na+/K+ pump in streptozotocin‐diabetic rats

“…Polyunsaturated fatty acids are also key structural components of cell membranes and several important membranebound enzymes (Horrobin, 1988). Disturbances in essential fatty acid content and abnormality of their incorporation into myelin and axons have been shown in streptozotocin-diabetic rats (Spritz et al, 1975;Lin et al, 1985). It is possible that essential fatty acid dietary supplementation could restore normal neuronal membrane structure and function.…”

The leptin receptor mutation of the obese Zucker rat causes sciatic nerve demyelination with a centripetal pattern defect

“…Interestingly, the Zucker obese rats bore myelin anomalies resembling the ones found in toxicantinduced diabetes in animals [43][44][45][46][47][48][49][50][51][52] and probably also thosenot studied by fine structurefound in unusual human cases of diabetes where leptin receptor was similarly incompetent. [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69] Therefore, the discussion of our demyelination data includes diabetes type 2 considerations along with leptin-linked endocrine interactions.…”