A combination therapy for androgenic alopecia based on quercetin and zinc/copper dual-doped mesoporous silica nanocomposite microneedle patch

A nanocomposite microneedle(ZCQ/MN)patch containing copper/zinc dual-doped mesoporous silica nanoparticles loaded with quercetin(ZCQ)was developed as a combination therapy for androgenic alopecia(AGA).The degradable microneedle gradually dissolves after penetration into the skin and releases the ZCQ nanoparticles.ZCQ nanoparticles release quercetin(Qu),copper(Cu^(2+))and zinc ions(Zn^(2+))subcutaneously to synergistically promote hair follicle regeneration.The mechanism of promoting hair follicle regeneration mainly includes the regulation of the main pathophysiological phenomena of AGA such as inhibition of dihydrotestosterone,inhibition of inflammation,promotion of angiogenesis and activation of hair follicle stem cells by the combination of Cu^(2+)and Zn^(2+)ions and Qu.This study demonstrates that the systematic intervention targeting different pathophysiological links of AGA by the combination of organic drug and bioactive metal ions is an effective treatment strategy for hair loss,which provides a theoretical basis for development of biomaterial based anti-hair loss therapy.

Design of a biofluid-absorbing bioactive sandwich-structured Zn-Si bioceramic composite wound dressing for hair follicle regeneration and skin burn wound healing

The deep burn skin injures usually severely damage the dermis with the loss of hair follicle loss,which are difficult to regenerate.Furthermore,severe burns often accompanied with large amount of wound exudates making the wound moist,easily infected,and difficult to heal.Therefore,it is of great clinical significance to develop wound dressings to remove wound exudates and promote hair follicle regeneration.In this study,a sandwich-structured wound dressing(SWD)with Janus membrane property was fabricated by hot compression molding using hydrophilic zinc silicate bioceramics(Hardystonite,ZnCS)and hydrophobic polylactic acid(PLA).This unique organic/inorganic Janus membrane structure revealed excellent exudate absorption property and effectively created a dry wound environment.Meanwhile,the incorporation of ZnCS bioceramic particles endowed the dressing with the bioactivity to promote hair follicle regeneration and wound healing through the release of Zn^(2+)and SiO^(2-)_(3)ions,and this bioactivity of the wound dressing is mainly attributed to the synergistic effect of Zn^(2+)and SiO^(2-)_(3)to promote the recruitment,viability,and differentiation of hair follicle cells.Our study demonstrates that the utilization of the Janus membrane and synergistic effect of different type bioactive ions are effective approaches for the design of wound dressings for burn wound healing.

In vitro degradation and surface bioactivity of iron-matrix composites containing silicate-based bioceramic

Iron-matrix composites with calcium silicate(CS)bioceramic as the reinforcing phase were fabricated through powder metallurgy processes.The microstructures,mechanical properties,apatite deposition and biodegradation behavior of the Fe-CS composites,as well as cell attachment and proliferation on their surfaces,were characterized.In the range of CS weight percentages selected in this study,the composites possessed compact structures and showed differently decreased bending strengths as compared with pure iron.Immersion tests in simulated body fluid(SBF)revealed substantially enhanced deposition of CaP on the surfaces of the composites as well as enhanced degradation rates as compared with pure iron.In addition,the composite containing 20%CS showed a superior ability to stimulate hBMSCs proliferation when compared to pure iron.Our results suggest that incorporating calcium silicate particles into iron could be an effective approach to developing iron-based biodegradable bone implants with improved biomedical performance.