Glutathione improves immune responses against M. avium infection

This study evaluates whether topically applied glutathione‑cyclodextrin nanoparticles (GSH‑CD) can be systemically absorbed and improve immune responses against Mycobacterium avium infection in healthy human subjects. Glutathione (GSH) is a critical intracellular antioxidant that protects cells from oxidative stress and supports immune function, but oral supplementation has limitations related to bioavailability. The authors investigated topical delivery as a noninvasive alternative to enhance systemic GSH levels.

In a randomized, placebo‑controlled design, 30 healthy participants received either topical GSH‑CD or placebo spray applied to the abdomen twice daily for three days. Blood samples were collected before treatment and at multiple time points following application. The researchers measured GSH levels, malondialdehyde (MDA—a marker of lipid peroxidation), and cytokine profiles in peripheral blood mononuclear cells (PBMCs) and red blood cells.

Results showed that topical GSH‑CD significantly increased intracellular GSH levels in PBMCs and red blood cells while reducing oxidative stress, as indicated by decreased MDA levels 72 hours after treatment. Functional immune assessment demonstrated that whole‑blood cultures from GSH‑CD–treated participants exhibited reduced survival of Mycobacterium avium when challenged in vitro, indicating enhanced antimicrobial immune activity.

The study concludes that topical delivery of glutathione via cyclodextrin nanoparticles is an effective method for elevating systemic antioxidant capacity and strengthening immune defenses. These findings suggest potential therapeutic applications for populations at increased risk of mycobacterial infections or oxidative stress–related immune dysfunction, supporting further investigation of topical GSH‑based interventions.