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Galardi-Castilla, M.

Publications and source records attributed to Galardi-Castilla, M..

3 recordsLinked to original sources

A paternal cardiac lesion induces cardiac adaptation in offspring

BackgroundFollowing cardiac injury, whether the heart is permanently damaged or regenerating, distal organs are subjected to changes in physiological function. It remains largely unknown whether a cardiac lesion can affect gametes and transmit heritable changes to subsequent generations. Here, we report the influence of paternal cardiac injury on the following generation. MethodsWe studied the intergenerational influence of neonatal cardiac injury in the mouse, an animal model capable of regenerating the heart after early life injury. Neonatal male mice were subjected to ventricular cryoinjury, crossed at adulthood, and their sires were compared with litters derived from uninjured male mice. We used echocardiography, histology, and single nuclei RNA-sequencing to thoroughly characterize cardiac morphology, composition, function, and response to cardiac insult. ResultsWe show that paternal cardiac injury affects the heart morphology of offspring under physiological conditions. Furthermore, in response to the same injury, the F1 generation derived from injured fathers shows better systemic and cardiac recovery, with non-pathological left ventricular enlargement and improved cardiac function during the regenerative process. This is accompanied by the activation of the immune system healing program at 3 weeks post-injury, together with enhanced transcription of genes associated with physiological hypertrophy. ConclusionsThe memory of a paternal neonatal lesion can be transmitted to offspring and improve their recovery from a cardiac insult.

developmental biology↗

Pre-existent adult sox10+ cardiomyocytes contribute to myocardial regeneration in the zebrafish

During heart regeneration in the zebrafish, fibrotic tissue is replaced by newly formed cardiomyocytes derived from pre-existing ones. It is unclear whether the heart is comprised of several cardiomyocyte populations bearing different capacity to replace lost myocardium. Here, using sox10 genetic fate mapping, we identified a subset of pre-existent cardiomyocytes in the adult zebrafish heart with a distinct gene expression profile that expanded massively after cryoinjury. Genetic ablation of sox10+ cardiomyocytes severely impaired cardiac regeneration revealing that they play a crucial role for heart regeneration.

developmental biology↗

Transient fibrosis resolves via fibroblast inactivation in the regenerating zebrafish heart

In the zebrafish (Danio rerio), regeneration and fibrosis after cardiac injury are not mutually exclusive responses. Upon cardiac cryoinjury, collagen and other extracellular matrix (ECM) proteins accumulate at the injury site. However, in contrast to the situation in mammals, fibrosis is transient in zebrafish and its regression is concomitant with regrowth of the myocardial wall. Little is known about the cells producing this fibrotic tissue or how it resolves. Using novel genetic tools to mark periostin b- and collagen 1alpha2 (col1a2)-expressing cells in combination with transcriptome analysis, we explored the sources of activated fibroblasts and traced their fate. We describe that during fibrosis regression, fibroblasts are not fully eliminated, but become inactivated. Unexpectedly, limiting the fibrotic response by genetic ablation of col1a2-expressing cells impaired cardiomyocyte proliferation. We conclude that ECM-producing cells are key players in the regenerative process and suggest that anti-fibrotic therapies might be less efficient than strategies targeting fibroblast inactivation.\n\nSCIENTIFIC STATEMENTAfter myocardial infarction in the mammalian heart, millions of cardiomyocytes are lost and replaced by fibrotic scar tissue. While fibrosis is persistent in adult mammals, there are some vertebrates, including zebrafish, with the capacity for regeneration. This process does not occur in the absence of fibrosis. Here we studied subpopulations of collagen producing cells and analyzed their fate after complete regeneration of the zebrafish myocardium. Our data show that fibroblasts persisted in the regenerated heart, but shut down the profibrotic program. While fibrosis could be considered as detrimental to the regeneration process, our study reveals a positive effect on cardiomyocyte proliferation. Accordingly, a fibrotic response can be beneficial for heart regeneration.

developmental biology↗