Fig. 6: Corisin induces increased expression of senescence markers in kidney cells.

A–F Induction of senescence-associated β-galactosidase (SAβGal) activity by corisin. Human Caki-2 cells (left panels), human primary renal tubular epithelial cells (middle panels), and normal human primary podocytes (right panels) were cultured in the absence or presence of 20 or 40 µg/mL of corisin, diluted in 0.5% recombinant human albumin (rhAlb), or 40 µg/mL of corisin with anti-corisin antibody. SAβGal activity was measured, and %SAβGal-positive cells was counted across multiple high-power fields using immunofluorescence microscopy. Scale bars represent 50 µm. Control, n = 6; corisin (20 µg/mL), n = 6; corisin (40 µg/mL), n = 6; corisin (40 µg/mL) + anticorisin (200 µg/mL), n = 6. Data are expressed as the mean ± SD. Statistical analysis by ANOVA followed by the Newman-Keuls test; all tests were two-sided. G–H Increased mRNA expression of senescence-associated factors in kidney cells by corisin. Normal human podocytes (n = 6) and normal human primary tubular epithelial cells (n = 5) were cultured in the absence or presence of 20 and 40 µg/mL corisin, diluted in 0.5% recombinant human albumin, or 40 µg/mL of corisin with anti-corisin antibody for 48 h. mRNA expression levels of cyclin-dependent kinase inhibitors p15 (CDKN2), p16 (CDKN2A), p21 (CDKN1A), p27 (CDKN1B), p53 (TP53), Ki-67 (MKI67), matrix metalloproteinase-12 (MMP12), and secreted phosphoprotein 1 (SPP1, also known as osteopontin) were evaluated by RT-PCR. Normally distributed data are presented as mean ± SD, while skewed data are expressed as the median with interquartile range. Statistical significance was assessed using ANOVA with the Newman-Keuls or Dunn’s test; all tests were two-sided. I, J Anticorisin antibody inhibits the expression of senescence markers. Diabetes mellitus (DM) was induced in transforming growth factor β1 (TGFβ1) transgenic (TG) mice by streptozotocin. The mice were divided into a DM TG/control IgG group (n = 5) and a DM TG/anticorisin group (n = 5). Wild-type (WT) mice injected intraperitoneally with saline (SAL, n = 4) served as controls. Paraffin-embedded kidney tissue sections were prepared for p21 immunofluorescent staining. Green immunofluorescent signals (red arrows) indicate p21 expression. The p21-positive area was quantified using WinROOF. Scale bars represent 100 µm. Data are presented as mean ± SD. Statistical significance was evaluated by ANOVA followed by the Newman-Keuls test; all tests were two-sided. The source data are available in the Source Data file.