Curcumin-zinc framework encapsulated microneedle patch for promoting hair growth.

Hair loss is a growing esthetic condition driven by complex mechanisms that has numerous psycho-social implications. Conventional drug applications usually focus on a single treatment target, and the penetration depth restricts the post-delivery effect. Method: We fabricated a curcumin-zinc framework (ZnMOF) encapsulated gamma-polyglutamic acid (γ-PGA) microneedle patch (ZnMOF-MN) as a multifunctional biosafe transdermal drug delivery system. ZnMOF was characterized with the field emission scanning electron microscope (FE-SEM), dynamic light scattering (DLS), elemental mapping, and X-ray diffraction (XRD). The topographical and hygroscopic features of ZnMOF-MN were characterized with SEM. The in vitro ZnMOF release profile and the in vivo penetration of ZnMOF-MN were also evaluated. The anti-oxidant, anti-apoptosis, and antiandrogen effects of ZnMOF solution and ZnMOF-MN extract were studied on mouse dermal papilla cells (DPCs). Two animal models (in C57BL/6 mice), including androgenic alopecia (AGA) model and wound healing model, were used to identify the therapeutic effect of ZnMOF-MN on hair regrowth and wound healing in vivo. Hair follicles, surrounding vessels (CD31+), and proliferating cells (Ki67+) were evaluated by histological staining. Results: ZnMOF crystals were cone-shaped nanoparticles with a size distribution of 424.9 ± 59.01 nm. ZnMOF-MN patch can create temporary holes in the skin to directly and evenly deliver bioactive ZnMOF particles to the targeted depth and achieve a steady and sustained release of Zn2+ and curcumin. In vitro, ZnMOF significantly improved the viability of DPCs against the excess reactive oxygen species (ROS) and inhibited the apoptosis induced by zinc deficiency. In addition, it also reversed the inhibitory effects of dihydrotestosterone (DHT) infiltration. Moreover, the ZnMOF-MN treatment has been proved to accelerate wound healing and increase hair follicles in wound healing models, and improved the hair regrowth in AGA animal models. Enhanced capillary density and cell proliferation observed in the CD31+ and Ki67+ staining of ZnMOF-MN group in both animal models also suggested that ZnMOF can facilitate angiogenesis and promote cell proliferation in the skin, respectively. Conclusion: The ZnMOF-MN treatment is a comprehensive solution with excellent therapeutic efficacy and patient-friendly features for promoting hair growth under various clinical conditions.

MXenes-integrated microneedle combined with asiaticoside to penetrate the cuticle for treatment of diabetic foot ulcer.

Patients with diabetic foot ulcers usually suffer from inefficient epithelisation and angiogenesis accompanied by chronic wound healing. Diabetic foot ulcers remain a major challenge in clinical medicine; however, traditional treatments are incapable of transdermal drug delivery, resulting in a low drug delivery rate. We report the development of Ti2C3 MXenes-integrated poly-γ-glutamic acid (γ-PGA) hydrogel microneedles to release asiaticoside (MN-MXenes-AS). Asiaticoside was loaded into PGA-MXenes hydrogel to facilitate cell proliferation while regulating angiogenesis. The characterisation and mechanical strength of the microneedles were investigated in vitro, and the wound-healing efficacy of the microneedles was confirmed in diabetic mice. MXenes significantly improved the mechanical strength of microneedles, while γ-PGA hydrogels provided a moist microenvironment for wound healing. Mice treated with MN-MXenes-AS demonstrated obvious improvements in wound healing process. We successfully fabricated an MXenes-integrated microneedle that possesses sufficient rigidity to penetrate the cuticle for subcutaneous drug delivery, thereby accelerating diabetic wound healing. We demonstrated that MN-MXenes-AS is effective in promoting growth both in vivo and in vitro. Collectively, our data show that MN-MXenes-AS accelerated the healing of diabetic foot ulcers, supporting the use of these microneedles in the treatment of chronic wounds.