Which enzyme is responsible for breaking down NAD+ in the body?

CD38 is main enzyme degrading NAD+ levels.

CD38 activity increases with age, lowering NAD+.

CD38 rapidly consumes NAD+ during immune activation.

PARPs also consume NAD+ during DNA repair.

Sirtuins use NAD+, but don’t degrade it.

CD38 considered biggest NAD+ sink in tissues.

Inflammation upregulates CD38, draining NAD+ faster.

CD38 knockout animals maintain higher NAD+ levels.

PARP overactivation depletes NAD+ under stress.

CD38 sits on cell surface breaking NAD+.

Aging increases CD38 expression across tissues.

Immune cells express high CD38 activity.

CD38 inhibition raises NAD+ availability significantly.

PARPs are secondary NAD+ consumers in cells.

CD38-driven NAD+ loss linked to metabolic decline.