Small peptide KR-12-a5 promotes the osteogenic differentiation of human bone marrow mesenchymalstem cells / 上海交通大学学报（医学版）

Objective: To investigate the effect of KR-12 analog, KR-12-a5, on osteogenic differentiation of human bone marrow mesenchymal stem cells (HBMSCs). Methods: Osteogenic differentiation-related experiments were performed using HBMSCs. KR-12-a5 was used as additional stimulation under osteogenesis inducing environment. By alkaline phosphatase (ALP) staining assay, ALP quantitative assay, alizarin red staining and elution quantitative analysis, and real-time quantitative polymerase chain reaction (RT-qPCR), the effect of KR-12-a5 on osteogenic differentiation of HBMSCs was verified. Results: As the concentration of KR-12-a5 increased, the staining intensity of ALP and alizarin red also increased. The strongest staining effect was exhibited at the highest concentration (50 μg/mL) of KR-12-a5. Quantitative tests showed similar results. After 3 days of stimulation with KR-12-a5, the mRNA level of RUNX2 increased in a dose-dependent manner. On the 7th day, the expression levels of ALP, COL1A1, BSP and BMP2 in the KR-12-a5-treated group showed significant changes. On the 14th day, OSX, OCN and OPN levels increased significantly. Conclusion: KR-12-a5 promoted the osteogenic differentiation of HBMSCs in a dose-dependent manner.

Profound Study for Functions of Antimicrobial Peptides in Prevention of Oral Disease.

Antimicrobial peptides (AMPs) have a widespread distribution in human body and have antimicrobial activity against microorganisms with wide-range class of host-defense molecules. These are small cationic peptides that play an important role in the development of innate immunity with activity against gram-positive and negative bacteria, parasites, fungi and some viruses. In the oral cavity, the AMPs are produced by the salivary glands and the oral epithelium and serve as defensive purposes. At least forty-five identifiable antimicrobial gene products found in saliva are secreted from oral epithelial cells, salivary glands and neutrophils. AMPs also serve as effective biological molecules in immune response activation, inflammation and wound healing The aim of this review was to discuss the types and functions of oral AMPs and their role in combating microorganisms and infections in the oral cavity. AMPs have a promising potential to be used against oral microbes in order to control their growth and biofilm formation. There are many challenges that need to be overcome in order to design and synthesize AMPs that have the ability to with stand the unique and harsh oral environment. AMPs are expected in the future to be used as models for developing effective oral microbial antibiotics.