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Biology subjects

Ghetti, A.

Publications and source records attributed to Ghetti, A..

3 recordsLinked to original sources

Single nucleus transcriptomics supports a role for CCNA2-induced human adult cardiomyocyte cytokinesis

Cyclin A2 (CCNA2), a master cell cycle regulator silenced in postnatal cardiomyocytes, promotes cardiac repair in animal models. However, its effect on cytokinesis in adult human cardiomyocytes remains unknown. We engineered a replication-deficient adenoviral vector encoding human CCNA2 under the cardiac Troponin T promoter and delivered it to freshly isolated cardiomyocytes from adult human hearts. Time-lapse live imaging revealed induction of complete cytokinesis with preservation of sarcomeres and calcium mobilization in redifferentiated daughter cardiomyocytes. To uncover underlying transcriptional mechanisms, single-nucleus transcriptomics of CCNA2-transgenic versus non-transgenic mouse hearts identified a cardiomyocyte subpopulation enriched for cytokinesis, proliferative, and reprogramming genes. Ultra-deep bulk RNA sequencing of adult and fetal human hearts further highlighted reprogramming pathways relevant to CCNA2-induced effects. Together, these findings demonstrate that CCNA2 can reinitiate cytokinesis in adult human cardiomyocytes and illuminate conserved molecular programs, supporting its promise as a regenerative gene therapy for the heart. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=99 SRC="FIGDIR/small/583057v7_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@b9cfa9org.highwire.dtl.DTLVardef@f0720eorg.highwire.dtl.DTLVardef@1d020b2org.highwire.dtl.DTLVardef@112c28b_HPS_FORMAT_FIGEXP M_FIG C_FIG CCNA2 Induces Cytokinesis and Drives Proliferation and Reprogramming of Adult Cardiomyocytes: An Integrative Transcriptomic Analysis across Human and Mouse Models.

cell biology↗

Functional Sexual Dimorphism in Human Nociceptors

The recent demonstration of differences in transcript expression in human post-mortem sensory neurons suggests the possibility of sexually dimorphic pain mechanisms. To date, however, the concept of "male" and "female" nociceptors has not been demonstrated at a functional level. We now report sensitization of female, but not male, human nociceptors by prolactin revealing a female-selective mechanism that can be exploited to improve the treatment of pain in women.

neuroscience↗

Computational design of peptides to target Nav1.7 channel with high potency and selectivity for the treatment of pain

The voltage-gated sodium NaV1.7 channel plays a key role as a mediator of action potential propagation in C-fiber nociceptors and is an established molecular target for pain therapy. ProTx-II is a potent and moderately selective peptide toxin from tarantula venom that inhibits human NaV1.7 activation. Here we used available structural and experimental data to guide Rosetta design of potent and selective ProTx-II-based peptide inhibitors of human NaV1.7 channels. Functional testing of designed peptides using electrophysiology identified the PTx2-3127 and PTx2-3258 peptides with IC50s of 7 nM and 4 nM for hNaV1.7 and more than 1,000-fold selectivity over human NaV1.1, NaV1.3, NaV1.4, NaV1.5, NaV1.8, and NaV1.9 channels. PTx2-3127 inhibits NaV1.7 currents in mouse and human sensory neurons and shows efficacy in rat models of chronic and thermal pain when administered intrathecally. Rationally-designed peptide inhibitors of human NaV1.7 channels have transformative potential to define a new class of biologics to treat pain.

biophysics↗