The adult mammalian heart has limited regenerative capacity, while the neonatal heart fully regenerates during the first week of life. Postnatal regeneration is mainly driven by proliferation of preexisting cardiomyocytes and supported by proregenerative macrophages and angiogenesis. Although the process of regeneration has been well studied in the neonatal mouse, the molecular mechanisms that define the switch between regenerative and nonregenerative cardiomyocytes are not well understood.
View Article and Find Full Text PDFMechanisms by which specific histone modifications regulate distinct gene networks remain little understood. We investigated how H3K79me2, a modification catalyzed by DOT1L and previously considered a general transcriptional activation mark, regulates gene expression during cardiogenesis. Embryonic cardiomyocyte ablation of Dot1l revealed that H3K79me2 does not act as a general transcriptional activator, but rather regulates highly specific transcriptional networks at two critical cardiogenic junctures: embryonic cardiogenesis, where it was particularly important for left ventricle-specific genes, and postnatal cardiomyocyte cell cycle withdrawal, with Dot1L mutants having more mononuclear cardiomyocytes and prolonged cardiomyocyte cell cycle activity.
View Article and Find Full Text PDFBesides transcription, RNA decay accounts for a large proportion of regulated gene expression and is paramount for cellular functions. Classical RNA surveillance pathways, like nonsense-mediated decay (NMD), are also implicated in the turnover of non-mutant transcripts. Whereas numerous protein factors have been assigned to distinct RNA decay pathways, the contribution of long non-coding RNAs (lncRNAs) to RNA turnover remains unknown.
View Article and Find Full Text PDFPLoS One
November 2021
Aims: Patients with cardiovascular comorbidities have a significantly increased risk for a critical course of COVID-19. As the SARS-CoV2 virus enters cells via the angiotensin-converting enzyme receptor II (ACE2), drugs which interact with the renin angiotensin aldosterone system (RAAS) were suspected to influence disease severity.
Methods And Results: We analyzed 1946 consecutive patients with cardiovascular comorbidities or hypertension enrolled in one of the largest European COVID-19 registries, the Lean European Open Survey on SARS-CoV-2 (LEOSS) registry.
Coronavirus disease 2019 (COVID-19) spawned a global health crisis in late 2019 and is caused by the novel coronavirus SARS-CoV-2. SARS-CoV-2 infection can lead to elevated markers of endothelial dysfunction associated with higher risk of mortality. It is unclear whether endothelial dysfunction is caused by direct infection of endothelial cells or is mainly secondary to inflammation.
View Article and Find Full Text PDFNeonatal mammalian heart has been shown to possess the capacity to regenerate substantially after an injury. This remarkable regenerative capacity is lost in a week. This transition has been marked with cardiomyocyte cell cycle arrest and induction of fibrotic response similar to what occurs after myocardial infarction in adult hearts.
View Article and Find Full Text PDFAims: Coronavirus disease 2019 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has emerged as a global pandemic. SARS-CoV-2 infection can lead to elevated markers of cardiac injury associated with higher risk of mortality. It is unclear whether cardiac injury is caused by direct infection of cardiomyocytes or is mainly secondary to lung injury and inflammation.
View Article and Find Full Text PDFMeis1, which belongs to TALE-type class of homeobox gene family, appeared as one of the key regulators of hematopoietic stem cell (HSC) self-renewal and a potential therapeutical target. However, small molecule inhibitors of MEIS1 remained unknown. This led us to develop inhibitors of MEIS1 that could modulate HSC activity.
View Article and Find Full Text PDFBackground: c-Myc plays a major role in the maintenance of glycolytic metabolism and hematopoietic stem cell (HSC) quiescence.
Objective: Targeting modulators of HSC quiescence and metabolism could lead to HSC cell cycle entry with concomitant expansion.
Methods And Results: Here we show that c-Myc inhibitor 10074-G5 treatment leads to 2-fold increase in murine LSKCD34low HSC compartment post 7 days.
The common prevalence of heart failure and limitations in its treatment are leading cause of attention and interest towards the induction of cardiac regeneration with novel approaches. Recent studies provide growing evidence regarding bona fide cardiac regeneration post genetic manipulations, administration of stimulatory factors and myocardial injuries in animal models and human studies. To this end, stem cells of different sources have been tested to treat heart failure for the development of cellular therapies.
View Article and Find Full Text PDFHeart has long been considered a terminally differentiated organ. Recent studies, however, have suggested that there is a modest degree of cardiomyocyte (CM) turnover in adult mammalian heart, albeit not sufficient for replacement of lost CMs following cardiac injuries. Cardiac regeneration studies in various model organisms including zebrafish, newt, and more recently in neonatal mouse, have demonstrated that CM dedifferentiation and concomitant proliferation play important roles in replacement of lost CMs and restoration of cardiac contractility.
View Article and Find Full Text PDFCrimean-Congo hemorrhagic fever virus (CCHFV) is a deadly virus that has been listed in the Category C as a potential bioterror agent. There are no specific therapies against CCHFV, which urges identification of potential therapeutic targets and development of CCHFV therapies. CCHFV OTU protease takes an important role in viral invasion through antagonizing NF-κB signaling.
View Article and Find Full Text PDFThere is an outmost need for the identification of specific antiviral compounds. Current antivirals lack specificity, making them susceptible to off-target effects, and highlighting importance of development of assays to discover antivirals targeting viral specific proteins. Previous studies for identification of inhibitors of RNA-dependent RNA polymerase (RdRp) mostly relied on radioactive methods.
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