Figure 1.

Senescent cell conditioned medium decreases α-Klotho; blocking particular SASP factors with neutralizing antibodies partially restores α-Klotho. (a-c) Conditioned media (CM) collected from senescent or non-senescent (a) human primary kidney endothelial cells (HKEs; one-way ANOVA: F = 19.10, p < 0.0001, R² = 0.89; n = 3; ****p < 0.0001); (b) human umbilical vein endothelial cells (HUVECs; one-way ANOVA: F = 3.02, p = 0.02, R² = 0.58, n = 3; *p = 0.02, **p = 0.01); or (b) human brain astrocytes (HBAs; one-way ANOVA: F = 7.93, p = 0.02, R² = 0.66; n = 5; ***p < 0.001, *p = 0.03) were applied to non-senescent HKEs, HUVECs, or HBAs, respectively, with or without antibodies against PAI-1, CXCL1, IL-6, activin A, TNF-α, IL-1α, IL-1β, or IL-18 for 48 h. α-Klotho mRNA was assayed by qPCR. Means ± SEM. (d) Primary HKEs (n = 4), (e) HUVECs (n = 4), or (f) HBAs (n = 4) were treated with recombinant activin A or IL-1α. α-Klotho was assayed by qPCR 24 h after treatments. Means ± SEM; unpaired T-tests; ***p < 0.001, ****p < 0.0001.