glutathione injections to lighten skin London Brightening: How They Work Glutathione Injection for Skin Whitening:

Cell viability was measured using the CellTiterBlue reagent (Promega, United States) according to the manufacturers protocol with Fluoroskan Ascent FL Microplate Reader (Thermo Labsystems, Waltham, MA, United States)

Jan-Mar 2017;6(1):115-119

Knockout of Cyp26a1 and Cyp26b1 during postnatal life causes reduced lifespan, dermatitis, splenomegaly, and systemic inflammation in mice

The enzyme cystathionine--synthase (CBS) that catalyzes the first step in the transsulfuration pathway is highly expressed in liver cells but not highly expressed in peripheral cells, so it is not surprising that the liver is the major producer of GSH, much of which is exported to the plasma and enzymatically broken down to cysteinylglycine and cyst(e)ine that is subsequently taken up by other cells for GSH synthesis