Search bioRxiv⌕ Search

bioRxiv · 10.1101/2023.12.19.572474

The transient formation of collaterals contributes to the restoration of the arterial tree during cardiac regeneration in neonatal mice

Abstract

Revascularization of ischemic myocardium following cardiac damage is an important step in cardiac regeneration. However, the mechanism of arteriogenesis has not been well described during cardiac regeneration. Here we investigated coronary artery remodeling and collateral growth during cardiac regeneration. Neonatal MI was induced by ligature of the left descending artery (LAD) in postnatal day (P) 1 or P7 pups from the Cx40-GFP mouse line and the arterial tree was reconstructed in 3D from images of cleared hearts collected at 1, 2, 4, 7 and 14 days after infarction. We show a rapid remodeling of the left coronary arterial tree induced by neonatal MI and the formation of numerous collateral arteries, which are transient in regenerating hearts after MI at P1 and persistent in non-regenerating hearts after MI at P7. This difference is accompanied by restoration of a perfused or a non-perfused LAD following MI at P1 or P7 respectively. Interestingly, collaterals ameliorate cardiac perfusion and drive LAD repair, and lineage tracing analysis demonstrates that the restoration of the LAD occurs by remodeling of pre-existing arterial cells independently of whether they originate in large arteries or arterioles. These results demonstrate that the restoration of the LAD artery during cardiac regeneration occurs by pruning as the rapidly forming collaterals that support perfusion of the disconnected lower LAD subsequently disappear on restoration of a unique LAD. These results highlight a rapid phase of arterial remodeling that plays an important role in vascular repair during cardiac regeneration. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/572474v3_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@5cb672org.highwire.dtl.DTLVardef@cdffc9org.highwire.dtl.DTLVardef@53e795org.highwire.dtl.DTLVardef@8920d0_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIRapid remodeling of the arterial tree is induced by myocardial infarction. C_LIO_LIThe endocardial response to ischemia differs between regenerated and non-regenerated hearts following myocardial infarction at postnatal days 1 or 7. C_LIO_LICollateral growth is rapid and transient in regenerated hearts while delayed and persistent in non-regenerated hearts. C_LIO_LICollateral arteries ameliorate cardiac perfusion and drive LAD repair. C_LIO_LIThe restoration of the LAD occurs by remodeling of pre-existing arterial cells. C_LI

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Miquerol, L., Sturny, R., Boulgakoff, L., Kelly, R. G.. 2023-12-20. The transient formation of collaterals contributes to the restoration of the arterial tree during cardiac regeneration in neonatal mice. https://doi.org/10.1101/2023.12.19.572474

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Proteome-wide quantification of protein turnover in frog and fly embryos reveals divergent strategies of maternal inheritance

Every embryo inherits a maternal proteome that it must remodel with zygotic proteins to build its many cell types. The fate of the maternal proteome remains contested because indirect measurements cannot resolve it. Here, we combine 18O-water labeling with multiplexed proteomics to quantify protein turnover proteome-wide in frog and fly embryos. Through hatching, the frog preserves the bulk of its maternal proteome, confining rapid degradation to a small regulatory module. The fly cannot meet its synthesis demand from yolk alone and instead degrades nearly all maternal proteins, including housekeeping proteins long assumed stable, recycling them into new protein. Yet the turnover hierarchy is conserved, with disordered and regulatory proteins degrading fastest, while the fly rescales the whole proteome ~eightfold faster. These results recast the developmental proteome as both informational inheritance and metabolic reserve, establish 18O-water labeling as a turnover method for non-feeding organisms, and provide a resource of embryonic half-lives.

developmental biology↗

The MAPK phosphatase VHP-1 buffers pharynx-to-body proportions against tissue-specific growth imbalance in C. elegans

Maintaining appropriate organ size ratios in the face of growth fluctuations is critical for the development of a reproducible body plan. Yet the mechanisms involved remain poorly understood. Here, we investigated how pharynx-to-body proportions are maintained in Caenorhabditis elegans, combining tissue-specific perturbations, genetic screening, and longitudinal live imaging. A genome-wide RNAi screen revealed that knock-down of the dual-specificity MAPK phosphatase VHP-1 turns animals hypersensitive to inter-tissue growth imbalance caused by pharyngeal or epidermal depletion of the mTORC1 activator RAGA-1 or the ribosomal protein RPL-22. In contrast, vhp-1 mutants tolerated global raga-1 loss, indicating a specific requirement for vhp-1 under tissue growth imbalance. Knock-down of the p38 pathway suppressed the imbalance-specific defects of vhp-1 mutants. In contrast, JNK knock-down effectively rescued the pleiotropic phenotypes of vhp-1 mutants but only weakly reduced their sensitivity to RAGA-1 imbalance, indicating that these two stress-MAPK pathways make distinct contributions to the response to growth imbalance. Finally, whole-animal VHP-1 levels increased upon epidermal RAGA-1 depletion, and epidermal VHP-1 depletion did not reproduce the sensitivity caused by global vhp-1 loss, consistent with a contribution from VHP-1 outside the growth-perturbed epidermis in buffering against local growth imbalance.

developmental biology↗

Network topology reveals distinct forms of developmental leverage in the Drosophila wing

Developmental gene regulatory networks reliably transform positional information into complex multicellular form, yet the organizational principles linking network architecture to developmental mechanism remain poorly understood. Here, we analyzed the Drosophila melanogaster wing developmental network to determine whether network topology reflects the distribution of developmental leverage during organogenesis. Integration of curated wing-development genes with high-confidence STRING interactions revealed five Hierarchical Layers of Developmental Control (HLDCs) associated with distinct topological and developmental roles. Organizer Centers, Signaling Scaffolds, and Pattern Implementers formed a forward-specification axis in which connectivity progressively contracted as positional information was transformed into increasingly localized developmental programs. Interface Coordinators departed from this hierarchy through disproportionate brokerage, whereas Local Modulators retained connectivity despite localized developmental scope. We propose that these complementary signatures reflect two regulatory architectures: 1) hierarchical information propagation that generates developmental identity and 2) distributed homeostatic regulation that coordinates and refines developmental outputs. Within Character Identity Modules (ChiMOs), this architecture links conserved patterning systems, Hox-defined contexts, and organ-specific kernels to reproducible morphology, providing a mechanistic hypothesis for developmental canalization and experimentally testable predictions.

developmental biology↗