caffeine metabolite

1,3,7-Trimethyluric acid, a purine alkaloid, occurs as a minor metabolite of caffeine in humans. It functions as an antioxidant with the ability to scavenge hydroxyl radicals and offers protective benefits against lipid peroxidation in erythrocyte membranes.

1-Methylxanthine is a caffeine derivative. 1-Methylxanthine is an essential human urinary metabolite of caffeine and theophylline (1,3-dimethylxanthine, TP). 1-Methylxanthine enhances the radiosensitivity of tumor cells.

Paraxanthine (1,7-dimethylxanthine) is a metabolite of caffeine (sc-202514) which functions as an adenosine receptor ligand and a PARP-1 inhibitor in pulmonary epithelial cells. Studies suggest that Paraxanthine is structurally similar to caffeine and possibly mediates the physiological effects of caffeine. Also Paraxanthine acts as a competitive phosphodiesterase inhibitor, which increases intracellular cAMP, activates PKA, inhibits TNF-α and leukotriene synthesis. In addition, Paraxanthine acts as a Na+ K+ ATPase enzymatic effector.

Methylliberine, an orally active purine alkaloid metabolite of caffeine, exhibits similar properties to its precursor.