glutathione precursor nac N.A.C. N-Acetylcysteine Meno Clinic NAC (N-Acetyl L-Cysteine):

One new possibility thats been explored is BPC-157

Powder liposomes employ the same technology as liquid liposomes and offer the same superior absorption

2.2 Use of Inhaled Glutathione for Treatment Lung infections, including cystic fibrosis, idiopathic pulmonary fibrosis, and lung disease in individuals with HIV

We demonstrate that IPA activates peroxisome proliferator-activated receptor alpha (PPAR) through specific ligand-binding domain interactions (Tyr314/Ile317), driving 3-hydroxy-3-methylglutaryl-CoA synthetase 2 (HMGCS2)-mediated ketogenesis to elevate -hydroxybutyrate (BHB) production

Int J Mol Sci 22(5):2331