The hair follicle (HF) is a multicellular complex structure of the skin that contains a reservoir of multipotent stem cells. Traditional hair repair methods such as drug therapies, hair transplantation, and stem cell therapy have limitations. Advances in nanotechnology offer new approaches for HF regeneration, including controlled drug release and HF-specific targeting. Until recently, embryogenesis was thought to be the only mechanism for forming hair follicles. However, in recent years, the phenomenon of wound-induced hair neogenesis (WIHN) or de novo HF regeneration has gained attention as it can occur under certain conditions in wound beds. This review covers HF-specific targeting strategies, with particular emphasis on currently used nanotechnology-based strategies for both hair loss-related diseases and HF regeneration. HF regeneration is discussed in several modalities: modulation of the hair cycle, stimulation of progenitor cells and signaling pathways, tissue engineering, WIHN, and gene therapy. The HF has been identified as an ideal target for nanotechnology-based strategies for hair regeneration. However, some regulatory challenges may delay the development of HF regeneration nanotechnology based-strategies, which will be lastly discussed.

Cell membrane‐coated biomimetic nanosystems have been recognized as promising drug delivery vehicles in recent years for the management of diverse skin conditions. Nanoparticles (NPs) coated with biomembranes, derived from either cell membranes or subcellular structures (e.g., extracellular vesicles), offer an opportunity to combine the biological interfacial characteristics of the coating alongside with the internal core component at the nanoscale. The biomimetic coating enhances the biocompatibility of NPs and their interaction with the skin, improving skin affinity, contact, and retention. This coating also enables the controlled release of drugs and provides skin‐targeting capabilities, which collectively improve the effectiveness, safety, and stability of topical and transdermal formulations. In this context, the current review delves into the recent progress in using biomimetic NPs for skin therapeutics. Specifically, it examines the various types of coatings, including their origins, heterogeneous functions, and surface molecular repertoires, in great detail. Additionally, this review presents the methods of preparing and characterizing biomimetic‐coated NPs. Furthermore, the potential of bioinspired NPs in treating a range of skin‐related conditions has been meticulously explored. Last, the toxicological aspects of these NPs have been thoroughly examined to provide a thorough summary of the evolution of biomimetic‐coated nanosystems for skin applications.

The wine industry is responsible for a considerable amount of waste produced by agricultural activities worldwide, which impacts both the economic sector and the environment through pollution and ecosystem imbalance. There are several examples of by-products generated during the winemaking process, such as grape pomace, vine leaves, grape stalks, or wine lees. These can be recovered and reused by the cosmetic industry, which is actively seeking natural and greener products. There are active ingredients that come from by-products that have relevant bioactive properties such as antioxidant, antiaging, anti-hyperpigmentation, or cellular protection. Therefore, the use of by-products from the wine industry as a source of active ingredients for topical application has attracted attention from the scientific community, overcoming some of the drawbacks of the winemaking process. Further research into extraction processes and methods is essential, as they directly influence the quality and quantity of recovered active ingredients. While current cosmetic products on the market undergo safety and cytotoxicity testing, it is important to evaluate the effects of pesticide treatments applied before pruning and the toxicity of the by-products to ensure the safety of future formulations. This review addresses a critical discussion on this subject, assessing the potential benefits of their use in topical formulations. Graphical Abstract

Antiandrogens are a family of drugs that block the biological effects of androgens, which are commonly used to treat a plethora of androgen-dependent conditions. However, their effectiveness highly depends on treatment compliance and their use is not exempt from side effects. Bicalutamide (BIC) is a testosterone blocker that, due to its peripheral tissue selectivity, offers the advantage of fewer side effects compared to other antiandrogens such as finasteride or dutasteride. In this study, BIC-loaded lipid vesicles (LVs) were developed and incorporated into a PVP/PVA-based Dissolving Microarray Patches (BIC-LVs@DMAPs) for BIC skin local delivery. First, the mechanical and insertion properties of the BIC-LVs@DMAPs were assessed. Then, the in vitro biocompatibility of the formulation was determined in keratinocytes. Finally, the effectiveness of the formulation to deliver BIC through skin was explored ex vivo using murine skin. BIC-LVs@DMAPs exhibited optimal mechanical and insertion properties to effectively perforate the stratum corneum and facilitate the passage of BIC-LVs. Ex vivo studies demonstrated the efficacy of BIC-LVs@DMAPs to improve the skin retention of BIC, while in vitro cytotoxicity results ensured their safety profile. Overall, these results pave the way for further in vivo studies and clinical application to improve the current early stages androgenetic alopecia topical treatments.

The anti-inflammatory drug ketoprofen has shown promising results in the field of drug repurposing for the treatment of brain cancer, but currently developed formulations are for invasive administration (intravenous) and have very limited drug strength. Hence, the purpose of this work was to develop an intranasal oil-in-water nanoemulgel, with drug strength maximization, for non-invasive, more effective and safer treatment of glioma. The developed formulations were made of Capryol^® 90 (hydrophobic surfactant), Tween^® 80 (hydrophilic surfactant), Transcutol^® (co-solvent and permeation enhancer), Pluronic^® F-127 (surfactant and gelling agent) and ketoprofen. Droplet size, polydispersity index, in vitro drug release and accelerated stability were measured. The results showed that the addition of Pluronic to a preliminary optimized nanoemulsion led to a significant droplet size and PDI reduction (176 to 22 nm and 0.3 to 0.1, respectively). The achieved drug strength was 4 mg/mL, which is more than 50 times higher than ketoprofen’s aqueous solubility. The developed formulations also appeared to have high stability, with instability indexes between 0.130 and 0.265, and a high cumulative drug release percentage, varying between 78 to 93% after 24 h. The formulations also showed a controlled release profile, fitting a Korsmeyer–Peppas kinetic model, with low AIC (43.84 to 54.67) and high R2 (0.9725 to 0.9971) values, depicting non-Fickian diffusion (n between 0.7 and 0.8). Hence, high-drug-strength, high-stability and high-drug-release ketoprofen-loaded nanoemulgels were successfully prepared. Future in vitro cytotoxicity evaluations in glioma cells will assess the true potential of the developed formulations for the treatment of brain cancer.