Fig. 1

Spontaneous Ca²⁺ oscillations and CaMKII activation are enhanced in human-derived ACM C-MSC. A–B Representative Ca²⁺ traces in C-MSC from HC donors and ACM patients loaded with Fura-2/AM. The measurements were performed on unstimulated cells cultured in GM. C–E The graphs represent: C percentage C-MSC displaying spontaneous Ca²⁺ oscillations (n = 567 cells; Two-tailed Student’s t-tests); D oscillation amplitude (n = 294 cells HC vs. n = 634 cells ACM; Two-tailed Student’s t-tests) and E oscillation frequency (n = 294 cells HC vs. n = 639 cells ACM; Two-tailed Student’s t-tests). F–G Expression of CAMK2G and CAMK2D isoforms in total RNA extracts of C-MSC from HC donors and ACM patients. GAPDH was used as a house-keeping gene and qRT-PCR data are presented as the genes threshold cycles (Ct) with respect to the housekeeping gene GAPDH (ΔCt) (n = 6 biological replicates; Two-tailed Student’s t-tests). H Representative images of WB analysis of proteins extracted from ACM and HC C-MSC cultured in GM, hybridized with anti-pCaMKII and anti-CaMKII antibodies. Immunostaining of the housekeeping H3 is shown for normalization. I–L Densitometric analysis of pCaMKII (n = 8 biological replicates) and CaMKII (n = 8 biological replicates) levels, normalized on H3 (Two-tailed Student’s t-tests). Data information: mean ± SEM. *P < 0.05, **P < 0.01 and ***P < 0.0001