
Open Access
Open Access
Open AccessGiven the complex pathogenesis of skin diseases, current treatments are not always adequate or suitable for all patients. This highlights the necessity for a multi-target therapeutic nanoplatform. Owing to their intrinsic biological functions, exosomes have emerged as a promising transdermal drug delivery system. However, native exosomes face bottlenecks in drug loading efficiency, tissue specificity, and scalability. This article aims to review the advances in engineered exosomes, focusing on cargo engineering, surface engineering, and manufacturing engineering. We outline the methods and strategies deployed for encapsulating functional molecules into exosomes or remodeling vesicle interface properties, with particular attention to the advantages and disadvantages of different technologies employed for engineering exosomes. Through rational design, exosomes can be engineered to achieved precise targeting, controlled delivery, combination therapeutic effects, and scalable production. They exhibit therapeutic potential in refractory skin diseases, including psoriasis, atopic dermatitis, scleroderma, chronic wounds, and skin malignancies, but there are still challenges regarding clinical standardization and quality control. Overall, engineered exosomes represent a new type of nanotherapeutic platform in the field of transdermal drug delivery. Exosome-based drug formulations have the potential to serve as delivery vehicles with more predictable and reproducible therapeutic effects.
Open Access
Open AccessObjective: Skin is a complex tissue whose health is modulated by multiple factors. Exposure to the environment causes damage to skin cells and skin tissue. Identification of factors that can improve skin cell function potentially can prevent or reverse skin aging. Fibroblast growth factors (FGFs) induce growth of skin cells and regulate multiple genes important for skin function. However, FGFs cannot penetrate skin and thus cannot be used as therapeutic factors. Methods: Here we tested three proline-containing tripeptides for their ability to induce skin cell growth, change gene expression within these cells, and protect cells from harmful agents. We also tested the ability of one peptide to penetrate skin, a prerequisite to influence skin cells in vivo. Results: We identified three short proline-containing tripeptides that increase both fibroblast and keratinocyte cell growth, increase the abundance of COL1A1 (collagen type 1) and AQP3 (aquaporin 3) mRNA transcripts and decrease IL6 (interleukin-6) transcripts, all features of improved skin health. These tripeptides, when used as a pretreatment, prevent an increase in the abundance of MMP1 (matrix metalloprotease 1), a biomarker of skin damage when these cells are treated with an aging compound. Finally, we show that one of these tripeptides can penetrate skin. Conclusions: Proline-containing tripeptides have properties that indicate they can be used to reduce or reverse skin damage.