Study objectives: To investigate whether noninvasive application of recurrent airway obstructions induces early release of mesenchymal stem cells into the circulating blood in a rat model of obstructive sleep apnea.
Design: Prospective controlled animal study.
Setting: University laboratory.
Patients or participants: Twenty male Sprague-Dawley rats (250-300 g).
Interventions: A specially designed nasal mask was applied to the anesthetized rats. Ten rats were subjected to a pattern of recurrent obstructive apneas (60 per hour, lasting 15 seconds each) for 5 hours. Ten anesthetized rats were used as controls.
Measurements and results: Mesenchymal stem cells from the blood and bone marrow samples were isolated and cultured to count the total number of colony-forming unit fibroblasts (CFU-F) of adherent cells after 9 days in culture. The number of CFU-F from circulating blood was significantly (P = 0.02) higher in the rats subjected to recurrent obstructive apneas (5.00 +/- 1.16; mean +/- SEM) than in controls (1.70 +/- 0.72). No significant (P = 0.54) differences were observed in CFU-F from bone marrow.
Conclusions: Application of a pattern of airway obstructions similar to those experienced by patients with sleep apnea induced an early mobilization of mesenchymal stem cells into circulating blood.