Cryoablation is a prostate cancer treatment which uses extreme cold to kill prostate cancer cells. Unfortunately,
cryoablation is not specific to cancer cells and normal cells within and surrounding the ice ball may also die which often
includes those in the neurovascular bundles (NVBs). The NVBs contain neuronal and vascular components essential for
erectile function and continence, and damage can cause impotence and incontinence. Therefore, agents that protect the
NVBs during cryoablative procedures are extremely important for the next generation of this technology. The purpose
of these studies was to analyze various agents for their ability to reduce cellular toxicity upon freezing of fibroblasts and
neuronal cells. The agents were compared against DMSO, a well accepted but toxic cryoprotective agent (CPA).
Various concentrations of trehalose, PVP, PEG, and DMSO were incubated with fibroblast or neuronal cells for 45
minutes at 37°C, frozen in liquid nitrogen for one hour, thawed in a 37°C water bath for 5 minutes, and then plated in 6
well plates. After 18 hours, live cells were counted using the trypan blue exclusion assay. No cells survived in DMEM
alone, however, cell viability was observed in the trehalose and DMSO treated samples in both cell types and in the
fibroblast cells only for PEG treated samples. To mimic the general cryoablation procedure consisting of 2 freeze/thaw
cycles, neuronal cells were frozen and thawed twice. Cell viability was observed in the some trehalose and DMSO
treated cells. Our experiments demonstrate that trehalose is capable of acting as a CPA of both fibroblasts and nerve
cells. Its overall ability to act as a CPA is comparable to DMSO, a widely used and well accepted CPA, thus warranting
further experimentation with this agent.
|