Sirt1, short for silent information regulator sirtuin 1, is a highly conserved NAD+-dependent deacetylase belonging to the sirtuin family. It acts as a post-translational regulator, modulating multiple biological processes such as inflammation, aging, mitochondrial biogenesis, autophagy, and more. Sirt1 affects these processes by deacetylating various proteins including histones and non-histones, and is involved in signaling pathways like NF-κB, AMPK, mTOR, P53, PGC1α, and FoxOs [1,2].

Sirt1 knockout (KO) or conditional knockout (CKO) mouse models have been used to study its role in different diseases. For example, in the context of aging, decreased Sirt1 expression in mice is associated with the aging process, while increased expression can extend lifespan [2]. In myocardial ischemia-reperfusion, Sirt1 activation protects the heart, and it regulates autophagy during this process through deacetylation of FOXOs, ATGs, and LC3 [4]. In autoimmune diseases, Sirt1 may be a novel therapeutic target as its altered functions are likely involved in the disease progression [3]. In colorectal cancer, Sirt1 is a potential therapeutic target as it regulates processes like apoptosis, autophagy, and proliferation in CRC cells [5].

In conclusion, Sirt1 is a key regulator in multiple biological processes. Model-based research, especially using KO/CKO mouse models, has revealed its crucial roles in diseases related to aging, inflammation, autoimmunity, and cancer. Understanding Sirt1's functions provides potential therapeutic strategies for these disease areas.