Fig. 7: LmnaF/F:mcm mice transduced with AAV9-DNhSUN1 show improved cardiac function and extended longevity.
A Transduction of AAV9-DNhSUN1 extends the lifespan of the LmnaF/F:mcm mice after tamoxifen induction. LmnaF/F:mcm + AAV9-DNhSUN1 transduced mice with the standard dose (2 × 1010 vg g−1) live for a median of 66 days post-Tmx induction, whereas the LmnaF/F:mcm + AAV9-GFP transduced mice have a shorter lifespan (36.5 days) (P < 0.0001; Log-rank (Mantel–Cox) test). All animals were induced with Tmx. B Transduction of a double dose (4 × 1010 VG/g) of AAV9 DNhSUN1 increases the lifespan of LmnaF/F:mcm animals. Male LmnaF/F:mcm injected with a double dose of DNhSUN1 live for an average of 205 days and females to 309 days post-Tmx induction, whereas the LmnaF/F:mcm injected with the standard dose DNhSUN1 have a shorter median lifespan (males 66 days, females 104 days). C Experimental procedure for AAV transduction. Tmx induction by IP injection at postnatal day 14, followed on day 15 in initial experiments by intrathoracic injection of AAV9-DNmSUN1 or AAV9-GFP as control (AAV). In subsequent experiments with the DNhSUN1 delivery was by retro-orbital injection. The expected lifespan of LmnaF/F:mcm injected with AAV9-GFP was 33 days after Tmx induction. The endpoint of this study is the date of death of LmnaF/F:mcm animals injected with AAV9-DNhSun1 (DOD). D The DNhSUN1 protein is detected by western blot analysis at 3 weeks after injection and after 1 year following injection at similar levels in whole heart lysates with an antibody specific to the C-terminus of human SUN1. A representative blot is shown for the number of animals (N = 2) per condition. Western blots were performed in triplicate. Markers in kDA (E + F) At 21 days after Tmx induction, extensive fibrosis (blue staining) was detected in LmnaF/F:mcm mice injected with AAV9-GFP (N = 5) in comparison to LmnaF/F:mcm animals treated with AAV9-DNhSUN1 (N = 5). The following genotypes served as controls: LmnaF/F + AAV9-DNhSUN1 (N = 5), LmnaF/F + AAV9-GFP (N = 4). Data are presented as mean ± SD. (scale bars 500 μm, 40 μm). G ECG analysis of mice injected with a standard AAV-DNhSUN1 dose shows improved cardiac function at day 28 after Tmx induction. H Cardiac function after transduction with AAV9-DNhSUN1 is improved in LmnaF/F:mcm animals. ECG analysis revealed an significant improvement of Fractional Shortening (FS), Global Longitudinal Strain (GLS) and Ejection Fraction in LmnaF/F:mcm + AAV9-DNhSun1 animals compared to LmnaF/F:mcm + AAV9-GFP control animals at day 28 (FS ***p = 0.0009; GLS ***p = 0.0003; EF ****p < 0.0001; One-way ANOVA with Tukey correction). Data were analyzed from the total number of animals (N) per genotype as indicated in the graph. Data are presented as mean ± SD. Source data are provided as a Source Data file.
