Yang Yang

Acne is a chronic inflammatory skin disease driven primarily by Propionibacterium acnes (P. acnes) colonization in hair follicles, which can progress from mild to severe forms and result in permanent scarring if left untreated. To resolve this problem, this study developed a polysaccharide-based light-heat-mediated soluble microneedle system for the transdermal delivery of antiacne agents encapsulated in mesoporous polydopamine nanoparticles (MPDA) for the effective treatment of acne vulgaris. A multifunctional microneedle (Cur-MPDA + Cur@HA/FPS MNs) based on hyaluronic acid and fucoidan (FPS) was prepared and functionalized by curcumin-loaded mesoporous polydopamine nanoparticles (Cur-MPDA) and backing containing curcumin, endowing it with a photothermal response, sustained-release, robust reactive oxygen species scavenging capacity, and antibacterial multiple properties. The microneedle system exhibited good mechanical strength and rapid tip dissolution within 2 min upon insertion. It demonstrated a strong antibacterial activity with 70.9% against P. acnes, good biocompatibility, and acne inflammation reduction. Most notably, when combined with NIR irradiation, the microneedle system achieved an outstanding antibacterial ratio of 99.4% against P. acnes and restored skin thickness to near-normal levels. Collectively, this microneedle system demonstrates a highly effective and patient-friendly approach to acne vulgaris treatment.

Biomimicry of the mucin barrier function is an efficient strategy to counteract influenza. We report the simple aminolyzation of poly(methyl vinyl ether-alt-maleic anhydride) (PM) using amine-terminated poly(ethylene glycol)ylated oleanolic acid (OAPEG) to mimic the mucin structure and its adsorption of the influenza virus. Direct interactions between influenza hemagglutinin (HA) and the prepared macromolecule evaluated by surface plasmon resonance and isothermal titration calorimetry demonstrated that the multivalent presentation of OAPEG on PM enhanced the binding affinity to HA with a decrease in K_D of approximately three orders of magnitude compared with monomeric OAPEG. Moreover, hemagglutination inhibition assay, viral growth inhibition assay, and cytopathic effect reduction assay indicated that the nonglycosylated polymer could mimic natural heavily glycosylated mucin and thus promote the attachment of the virus in a subnanomolar range. Further investigation of the antiviral effects via time-of-addition assay, dynamic light scattering experiments, and transmission electron microscopy photographs indicated that the pseudomucin could adsorb the virion particles and synergistically inhibit the early attachment and final release steps of the influenza infection cycle. These findings demonstrate the effectiveness of the macromolecule in the physical sequestration and prevention of viral infection. Notably, due to its structural similarities with mucin, the biomacropolymer also has the potential for the rational design of antiviral drugs, influenza adsorbents, or filtration materials and the construction of model systems to explore protection against other pathogenic viruses.