Background: There is an increasing attention towards stem cells exosomes and their regenerative potential, bone-marrow derived stem cells exosomes was shown to enhance tissue regeneration. Objective: To explore the effect of bone-marrow derived stem cells exosomes on circumvallate papillae subjected to cyclophosphamide chemotherapy.
Methods: Forty-four adult male albino-rats, weighing between 180 and 200grams were used. Two rats were used as a source of bone-marrow stem cells exosomes and the rest were divided equally into 3 groups; 14 rats each as follows: Group I: Control; Group II: Cyclophosphamide group, this group received a single dose (150mg/kg) of cyclophosphamide intraperitoneal; Group III: exosomes group, this group received a single dose (150mg/kg) of cyclophosphamide intraperitoneal then after two days, they received single dose of bone-marrow mesenchymal-stem cells (BM-MSCs)-derived exosomes (100μg) suspended in 1ml phosphate buffered saline intraperitoneal. All groups were sacrificed on day 9 of the experiment. Circumvallate papillae were examined histologically and ultra-structurally. The inflammatory cell counts and percentage of cytoplasmic vacuolation were statistically analyzed.
Results: A significant improvement in the shape and size of cells of circumvallate papillae was noticed in both epithelium and connective tissue compared to the samples subjected to cyclophosphamide only, the ultrastructural examination of the tissues showed significant improvement in all cellular organelles especially nuclei shapes, endoplasmic reticulum and mitochondria. A statistically significant decrease in inflammatory cells and vacuolation percentage was also revealed. Conclusion: Bone-marrow derived stem cells exosomes could be considered an effective regenerative treatment for cyclophosphamide induced circumvallate papillae damage.