Oxidative Stress

Dual-mechanism vitamin C delivery by polyethylene glycol-23 glyceryl distearate-based niosomes via SVCT2 induction and enhanced transdermal penetration.

Drug delivery

Abstract

Polyethylene glycol-23 glyceryl distearate (GDS-23)-a noisome-forming diacylglycerol-polyethylene glycol-based nonionic surfactant-functions as a nanocarrier for drug delivery systems (DDS) and an enhancer of endogenous antioxidant capacity through nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Here, we evaluated the potential of GDS-23 as a multifunctional DDS carrier by investigating the combined contribution of (i) improved transdermal delivery mediated by niosomal DDS and (ii) increased cellular uptake associated with induction of antioxidant-related transporters, using protection against oxidative-stress-induced tissue damage as a functional readout. We determined whether GDS-23 modulates the expression of the antioxidant-related transporters xCT and SVCTs through Nrf2 activation. In normal human epidermal keratinocytes, GDS-23 treatment significantly upregulated the mRNA expression of xCT (SLC7A11; cystine/glutamate antiporter) and sodium-dependent vitamin C transporter 2 (SVCT2). The induction was diminished by an Nrf2 activation inhibitor (K67), indicating involvement of the Nrf2 pathway. Furthermore, evaluation using a three-dimensional reconstructed epidermis model with calcein sodium as a fluorescent tracer revealed that GDS-23-based niosomes facilitated skin permeation. When L-ascorbic acid or cysteine was encapsulated within these niosomes, hydroquinone-induced oxidative tissue damage was attenuated, with the L-ascorbic acid-loaded niosomes exhibiting the most prominent protective effect. Overall, this study shows that Nrf2 activation contributes to SVCT2 induction and that GDS-23 is a multifunctional DDS nanocarrier that enhances skin permeation and may promote intracellular uptake by upregulating antioxidant-related transporters. These findings highlight the therapeutic potential of combining functional nanocarriers with entrapped bioactive molecules, offering a promising strategy for efficient treatment of skin disorders and antioxidant-based interventions.

Key Findings

  • GDS-23 treatment significantly upregulated mRNA expression of antioxidant-related transporters xCT and SVCT2 via Nrf2 activation in human epidermal keratinocytes.
  • Nrf2 activation inhibitor K67 diminished the induction of xCT and SVCT2, confirming the involvement of the Nrf2 pathway.
  • GDS-23-based niosomes enhanced skin permeation and, when loaded with L-ascorbic acid or cysteine, attenuated hydroquinone-induced oxidative tissue damage, with L-ascorbic acid showing the most prominent protective effect.

Clinical Significance

This study demonstrates that GDS-23 nanocarriers activate Nrf2 to induce antioxidant transporters and enhance transdermal delivery of vitamin C, offering a promising therapeutic strategy for protecting skin against oxidative stress-related damage.

Citation

Miyoshi Tatsuro, Keller Brian C, Nakagawa Suiet al.. Dual-mechanism vitamin C delivery by polyethylene glycol-23 glyceryl distearate-based niosomes via SVCT2 induction and enhanced transdermal penetration. Drug delivery. 2026-Dec-31.

DOI: 10.1080/10717544.2026.2681287