Poly-lactic Acid Dermal Filler Enriched With InCube-encapsulated Vitamin C and Glutathione: Preclinical Evidence of Superior Collagen Induction and Tissue Response Compared With Conventional PLA.

[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. , 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. , 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.