Fig. 6

Metformin promotes the production of TNF-α in senescence T cells. Analysis of TNF-α-secreting cells from CD8 + senescent T cells (CD3 + CD8 + CD45RA + CCR7-CD27-CD28-CD57 + KLRG1 +) (a) and CD3 + CD8 + CD45RA + CCR7-CD27-CD28-CD57-KLRG1-T cells (c) in the control group and the 20 mM Met treatment group in middle-age group. b The frequency of TNF-α + CD8 + senescent T cells in lymphocytes between the control and Met treatment group. d Representative flow histogram of TNF-α in CD8 + CD45RA + CCR7-CD27-CD28-CD57 + /CD57-T cell and the percentage and MFI of TNF-α in CD8 + CD45RA + CCR7-CD27-CD28-CD57 + /CD57-T cell. Expressed as the mean ± SEM. **P < 0.01; Paired t test. Met, metformin