Evaluation of the effect of photobiomodulation on osteogenic differentiation of adipose derived mesenchymal stem cells loaded in metacrylated gelatin hydrogel scaffolds for reconstruction of critical sized bone defect model

The aim of this study was to evaluate the regenerative effect of photobiomodulation (PBM) administered using polychromatic light sources on bone formation and on differentiation of adipose derived mesenchymal stem cells. 36 Sprague-Dawley male rats were divided into 3 equal groups randomly biparietal full thickness cranial bone defects (6mm. in diameter) were created. First group eas the control group, and the second group recieved metacrylated gelatin hydrogel scaffold (JEL-MA). Third experimental group was treated with adiposed derived mesenchymal stem cells loaded metacrylated gelatin hydrogel scaffold (AkMKH+JEL-MA). Each group was subdivided and half of them received FBM while other half did not. Macroscopic, histologic and microtomographic assessments were performed at 20th week after transplantation to evaluate bone formation. Histologically, in means of new bone formation significantly better results were observed in JEL-MA and AkMKH+JEL-MA groups compared to control group (p<0.001). Microtomographic evaluation revealed highest bone formation in AkMKH+JEL-MA group. FBM – samples show 60.62±6.34 percent bone formation in average whereas FBM+ samples displayed mean 79.93±3.41 percent of bone formation. FBM administration significantly affected mikrotomographic results bone formation (p=0.002). In conclusion, administration of photobiomodulation in polychromatic fashion appears to stimulates new bone formation and may stimulate adipose derived mesenchymal stem cells on osteogenic differentiation. Key Words: photobiomodulation, metacrylated gelatin hydrogels, mesenchymal stem cells, bone tissue engineering, critical sized bone defect