"...treatment with DNA-PK inhibitor protects against aging-associated decline in metabolism and physical fitness without increasing DSBs [double-strand breaks].

"...treatment with DNA-PK inhibitor protects against aging-associated decline in metabolism and physical fitness without increasing DSBs [double-strand breaks]... The most likely explanation for this paradox is that the ... DNA-PK inhibitor, like most inhibitor drugs, is a partial inhibitor at physiological doses. The residual DNA-PK activity may be sufficient to protect against the level of DNA DSBs generated naturally."