The Effect And Mechanism Study Of Exosomes From Adipose-derived Stem Cell On Hair Regeneration

Background.Alopecia is a widespread dermatologic disorder characterized by shortened anagen and prolonged telogen phases in the hair cycle.Currently,finasteride and minoxidil are the only two available drugs approved by the U.S.Food and Drug Administration(FDA)for alopecia treatment.However,the treatment satisfaction of hair loss is far from expected due to the limitations of long treatment cycle,and drug side effects,etc.So,alopecia treatment is still a difficult and hot issue in the academic world.The growth of hair is widely recognized as a result of the periodic remodeling of the hair follicles(HFs).Within the duration of remodeling,the dermal papilla cells(DPCs),a specialized mesenchymal cell that localized beneath the bottom of HFs,play key roles in modulation of the development of HFs.Accumulating evidence has shown that mesenchymal stem cells and their derivatives hold great promise for the treatment of hair loss.However,the exosomes from adipose-derived stem cell(ADSC-Exos)were rarely reported in alopecia treatment.Objective.The aim of this study was to evaluate the effects of ADSC-Exos on hair regeneration both in vitro and in vivo,as well as the underlying mechanism.Methods.We examined changes in cell proliferation,migration,and apoptosis of dermal papilla cells(DPCs)treated with ADSC-Exos and growth of hair shaft through in vitro hair follicle organ culture.In vivo,the C57BL/6 hair-depilated mice in hair telogen model was established to detect therapeutic efficacies when subcutaneously injecting ADSC-Exos alone or combined with minoxidil.At the same time,the expression of ki67 and β-catenin protein in skin from each group mouse was detected after treatment.Finally,RNA-seq,q RT-PCR and western blot were used to explore the related mechanisms of ADSC-Exos in promoting hair regrowth.Results.In results,ADSC-Exos significantly promoted DPCs proliferation and migration while also reducing apoptosis.Through in vitro hair follicle organ culture,we found that ADSC-Exos potentially promoted the growth of hair shafts of cultured hair follicles.Additionally,in comparison with the control group,ADSC-Exos treatment mice showed better hair growth,as well as increased hair follicle number,dermis thickness,ki67 cell proliferation markers and β-catenin expression.RNA sequencing(RNA-seq)revealed that miR-22 was markedly down-regulated in the DPCs after ADSC-Exos treatment.At the same time,the Wnt/β-catenin pathway was activated in the skin of ADSC-Exos therapy mice,according to q RT-PCR and western blot results.Conclusion.ADSC-Exos therapy displayed a positive impact on promoting hair regrowth by downregulating miR-22 and upregulating Wnt/β-catenin pathway,implying that ADSC-Exos could be a promising cell-free therapeutic strategy for alopecia in the future.