l-Theanine extends lifespan of adult Caenorhabditis elegans

PURPOSE Compounds that delay aging in model organisms may be of significant interest to anti-aging medicine, since these substances potentially provide pharmaceutical approaches to promote healthy lifespan in humans. We here aimed to test whether pharmaceutical concentrations of L-theanine, a putative anti-cancer, anti-obesity, blood pressure-lowering, and neuroprotective compound contained in green tea (Camellia sinensis), are capable of extending lifespan in a nematodal model organism for aging processes, the roundworm Caenorhabditis elegans. METHODS Adult C. elegans roundworms were maintained on agar plates, were fed E. coli strain OP50 bacteria, and L-theanine was applied to agar to test (1) whether it may increase survival upon paraquat exposure and (2) whether it may promote longevity by quantifying survival in the presence and absence of the compound. RESULTS L-Theanine increases survival of C. elegans in the presence of paraquat at a concentration of 1 micromolar. L-theanine extends C. elegans lifespan when applied at concentrations of 100 nM, as well as 1 and 10 micromolar. CONCLUSIONS In the model organism C. elegans, L-theanine is capable of promoting paraquat resistance and longevity suggesting that this compound may as well promote healthy lifespan in mammals and possibly humans.