SIRT1 and cyclic hematopoiesis: We established in vitro and in vivo CH models and applied a string of functional assays and molecular mechanism experiments to probe into the potential upstream regulation of SIRT1 including circ-SIRT1 (hsa_circ_0093884) and its conserved mouse homolog circ-Sirt1 (mmu_circ_0002354) in CH, attempting to identify circ-SIRT1 as a novel target for the improvement of CH treatment.