Individual supplementation of many TCA cycle metabolites extends mean lifespan in
. (A) Succinate extends lifespan, (B) citrate does not extend lifespan, (C) alpha-ketoglutarate extends lifespan, and (D) isocitrate extends lifespan at one or more of the concentrations tested. 10 mM citrate is a standard component of the S-medium. It was removed to determine the effect of citrate on lifespan.