Abstract: Objective: To study the effects of N-Ac-L-Leu-PEI/micro RNA(miR)-34a complex on osteogenisis of rat cranial defects. Methods: Thirty-two Wistar male rats were randomly divided into four groups and standard cranial defects were prepared on each rat. Biofilms loaded with PBS, N-Ac-L-Leu-PEI, N-Ac-L-Leu-PEI/miR-34a complex, and N-Ac-L-Leu-PEI/miR-34a NC complex covered the defect. After ten weeks culture, the rats were sacrificed and the development of osteogenisis was detected by CBCT, micro-CT and RT-PCR. Results: Bone formation was evident in the defects of N-Ac-L-Leu-PEI / miR-34a complex group. The BV/TV values and Tb.Th values of N-Ac-L-Leu-PEI/miR-34a complex group increased significantly, suggesting new bone formation. The expression of Runx2, SP7, and Col I mRNA was up-regulated by N-Ac-L-Leu-PEI/miR-34a complex, which were specific factors of osteogenisis. Conclusion: N-Ac-L-Leu-PEI/miR-34a complex can promote osteogenesis in rat cranial defects.

Key words: miR-34a, N-Ac-L-Leu-PEI, N-Ac-L-Leu-PEI/miR-34a complex, Rat cranial defects