Sirtuin 2 (SIRT2), as a member of the sirtuin family, has representative features of evolutionarily highly conserved nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase activity. In addition, SIRT2, as the only sirtuin protein colocalized with tubulin in the cytoplasm, has its own functions and characteristics. In recent years, studies have increasingly shown that SIRT2 can participate in the regulation of gene expression and regulate signal transduction in the metabolic pathway mainly through its post-translational modification of target genes; thus, SIRT2 has become a key centre in the metabolic pathway and participates in the pathological process of metabolic disorder-related diseases. In this paper, it is discussed that SIRT2 can regulate all aspects of gene expression, including epigenetic modification, replication, transcription and translation, and post-translational modification, which enables SIRT2 to participate in energy metabolism in life activities, and it is clarified that SIRT2 is involved in metabolic process-specific signal transduction mechanisms. Therefore, SIRT2 can be involved in metabolic disorder-related inflammation and oxidative stress, thereby triggering the occurrence of metabolic disorder-related diseases, such as neurodegenerative diseases, tumours, diabetes, and cardiovascular diseases. Currently, although the role of SIRT2 in some diseases is still controversial, given the multiple roles of SIRT2 in regulating physiological and pathological signal transduction, SIRT2 has become a key target for disease treatment. It is believed that with increasing research, the clinical application of SIRT2 will be promoted.

Levosimendan and milrinone are 2 effective inotropic drugs used to maintain cardiac output in acute heart failure (AHF). Using data from patients with AHF with and without abnormal renal function, we performed this single-center, retrospective cohort study to compare the effectiveness and safety of milrinone and levosimendan for the initial management of AHF. Patients admitted for heart failure between December 2016 and September 2019 who received levosimendan or milrinone as initial inotrope therapy in the cardiology department were identified. A total of 436 levosimendan and 417 milrinone patients with creatinine clearance (CrCl) $30 mL/min and 50 levosimendan and 71 milrinone patients with CrCl ,30 mL/min or on dialysis were included. The primary outcome was a composite of changes in clinical status at 15 and 30 days after initial inotrope therapy discontinuation. Between subgroups of patients with CrCl $30 mL/min, there were no significant differences in primary outcomes; milrinone was associated with more frequent hypotension and cardiac arrhythmias during the infusion period (P , 0.01), while levosimendan was associated with more frequent cardiac arrhythmias within 48 hours after discontinuation (P , 0.05). Of the patients with CrCl ,30 mL/min or on dialysis, more initial levosimendan than milrinone patients and those who switched to alternative inotropes experienced clinical worsening at 15 days and 30 days (P , 0.05). According to our results, patients with AHF with severe renal dysfunction should avoid initial inotrope therapy with levosimendan.