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Cell biology

Glutathione

DEGlutathion

Glutathione (GSH) is your cells' main built-in antioxidant. It is a small molecule (a thiol) that your body makes in two energy-using steps from three amino acids: glutamate, cysteine, and glycine, with help from the enzymes glutamate-cysteine ligase (GCL) and glutathione synthetase. It does a few key jobs. It feeds enzymes called glutathione peroxidases (GPx) that mop up hydrogen peroxide and damaged fats. It tags toxins for disposal (through glutathione S-transferases). And it keeps your proteins in the right chemical state. Here is the catch: your total glutathione tends to fall with age in most tissues, partly because you make less of it and partly because oxidative load rises. A low ratio of active to spent glutathione (GSH:GSSG) is linked to faster cellular aging and disease risk. That is why supplements like N-acetylcysteine and glycine are being tested to rebuild glutathione levels in older adults.

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