Abstract
The loss of Schwann cells in the peripheral nerves is thought to be responsible for the pathologies associated with diabetic neuropathy. As diabetes causes increased
extracellular glucose levels, glycosylation or non-enzymatic glycation of cell surface receptors may interfere with normal signaling between axons and Schwann cells and trigger the apoptotic pathway in Schwann cells. In this study, I tested the hypothesis that high glucose levels emulating hyperglycemia stimulate apoptosis in cultured Schwann
cells. Schwann cells were isolated from two-day-old rat pup sciatic nerves, placed in primary culture, and then incubated in the presence of elevated glucose levels for one to
seven days. The glial marker S100 monoclonal antibody identified Schwann cells, and apoptosis was detected using the terminal deoxynucleotidyl transferase mediated dUTP
nick end labeling (TUNEL) method. Approximately 50% of the Schwann cells exposed to elevated glucose levels were apoptotic after 24 hours of incubation, and apoptosis of
Schwann cells increased with increasing time in culture to 71% on day six in culture. This finding indicates that increased extracellular levels of glucose results in Schwann
cell apoptosis in vitro.
