Relationships between HSCs and their supporting niche cells are functionally impaired in old age. But, the senile hematopoietic system can be restored by young mobilized peripheral blood, HSC. MicroRNAs in secreted microvesicles are responsible for improving hematopoietic functions by increasing the expression of genes targeting MYC and E2F and decreasing p53 expression. During recovery, an increase in the number of NK killers was observed, which could eliminate senescent cells as they appeared in various organs. The regenerated cells may also assist in the regeneration of aged hematopoietic and non-hematopoietic supporting cells in the bone marrow microenvironment.