David Sinclair, Ph.D.
Harvard Medical School
Sirtuin biology and NAD+ precursor longevity research.
NAD+ is a coenzyme present in every living cell, essential for mitochondrial energy metabolism, redox reactions, and DNA repair via PARP enzymes. It also serves as a substrate for sirtuins, which regulate chromatin structure and stress responses. Endogenous NAD+ levels decline with age, making it a central focus of longevity research.
Mechanism of action
- Cycles between NAD+ and NADH to shuttle electrons in mitochondrial ATP production.
- Substrate for sirtuins (SIRT1–7), enzymes regulating metabolism and chromatin state.
- Cofactor for PARP enzymes involved in DNA damage repair.
Research highlights
- NAD+ depletion is a hallmark of aging across multiple model systems.
- Active clinical research on NAD+ precursors (NR, NMN) in metabolic and cognitive endpoints.