Protective/Restorative Role of the ADMSC on the RAI-induced Salivary Gland Damage in Rats
Objective: We evaluated protective/regenerative effects of adipose tissue-derived mesenchymal stem cells (ADMSC) on RAI-induced salivary gland damage in rats.
Methods: Study population consists of controls (n:6) and treatments (n:54); RAI (Group 1), ADMSC (Group 2), amifostine (Group 3), RAI/amifostine (Group 4), RAI/ADMSC concomitantly (Group 5) or after 48 h (Group 6). We used light microscopy (LM), transmission electron microscopy (TEM) and salivary gland scintigraphy (SGS), and analyzed data statistically.
Results: We observed the homing of ADMSC in salivary glands at 1st month by LM. Necrosis, periductal fibrosis, periductal sclerosis, vascular sclerosis and a total sum score were statistically affected by RAI exposure (P<0.05). In intragroup comparisons LM during 1st and 6th month revealed statistically significant improvements for Group 6 (P<0.05) but not for Groups 4/5. Intergroup comparisons of the total score showed Groups 4/5 in 1st month and Group 6 in 6th month had the lowest value. TEM showed vacuolization, edema, and fibrosis in 1st month and an improvement in damage in 6th month for Groups 5/6. SGSs revealed significant differences for Smax (P=0.007) and G/BGmax (P=0.005) in 1st month, for G/BGmax (P=0.005), Smax (P=0.005) and Tmax/Tmin (P=0.027) in 6th month. Between 1st and 6th month scans there were differences for Smax and G/BGmax (P=0.04), but not for Tmax/Tmin (p>0,05). We observed a prominent deterioration in gland function in-group 1, whereas, mildly to moderate deteriorations in protective treatment groups.
Conclusion: Our results indicate that ADMSC may play a promising role as the protective/regenerative agent against RAI-induced salivary gland dysfunction.