Background/Aim: Poly-Lactic acid (PLA) fillers are widely used for facial and body volume restoration because of their collagen-stimulating properties. However, early inflammation, oxidative stress, and variable long-term remodeling remain as concerns. Vitamin C and glutathione support collagen synthesis and redox homeostasis but degrade rapidly in conventional systems. This study evaluated a PLA filler incorporating Ethyl ascorbic acid (Vitamin C) and glutathione stabilized within an InCube® microlattice (PLA-IC) focusing on antioxidant stability, collagen induction, and tissue response. Materials and Methods: PLA-IC were prepared by combining PLA microspheres with microlattice-encapsulated vitamin C and glutathione. Scanning and transmission electron microscopy and selected-area electron diffraction were used to characterize particle morphology and structure. Antioxidant stability was examined using high-performance liquid chromatography and DPPH radical-scavenging assays during long-term storage. In vivo, SKH mice received subcutaneous injections of PBS, commercial PLA filler, or PLA-IC. Surface volume changes were measured by Primos imaging, and histology was used to assess inflammation, neovascularisation, and collagen deposition over 12 weeks. Results: Microlattice encapsulation preserved vitamin C and glutathione for 277 days and maintained strong DPPH-scavenging activity for up to 200 days. In vivo, PLA-IC showed significantly greater volumizing effect than standard PLA filler between weeks 4 and 12. Masson’s trichrome staining demonstrated higher collagen density in the PLA-IC group, reaching nearly twice that of conventional PLA at 12 weeks. H&E sections revealed reduced inflammatory infiltration and minimal neovascularisation in PLA-IC-treated tissues. Conclusion: Microlattice-based incorporation of vitamin C and glutathione enhances the antioxidants stability and overall biostimulatory performance of PLA filler. Compared with conventional PLA, PLA-IC demonstrated improved volume retention, increased collagen formation, and a more controlled tissue response, indicating potential advantages for aesthetic applications and warranting clinical evaluation of safety and efficacy.
JANG et al. (Fri,) studied this question.