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Procida-Kowalski, T.

Publications and source records attributed to Procida-Kowalski, T..

5 recordsLinked to original sources

Endothelial expression of ZBTB16 protects against cardiac aging

Background and aimAging significantly increases the risk of cardiovascular diseases, characterized by progressive cardiac dysfunction. The vascular niche is crucial for maintaining cardiac homeostasis, yet endothelial cell (EC) impairment during aging remains poorly understood. This study investigates epigenetically regulated mechanisms mediating EC-dependent cardiac aging and identifies a critical role of Zinc finger and BTB domain-containing protein 16 (ZBTB16). MethodsChromatin accessibility (snATAC-seq) and transcriptomic (snRNA-seq) analyses were performed on aged hearts to identify age-related regulatory changes. Functional studies using genetic models, assessed cardiac aging phenotypes. In vitro assays examined EC senescence and secretory profiles, while co-culture experiments analyzed the impact of ZBTB16-deficient EC supernatants on fibroblasts, cardiomyocytes, and neurons. Overexpression experiments in vitro and in vivo tested the potential for ZBTB16 to mitigate aging-associated dysfunction. ResultsAged hearts exhibited decreased chromatin accessibility and expression of the transcription factor ZBTB16 in both human and mice. Loss of ZBTB16 in young mice, including Zbtb16 haploinsufficient and endothelial-specific knockout mice, led to premature aging, diastolic dysfunction, and increased secretion of pro-fibrotic and inflammatory factors. Supernatants from ZBTB16-deficient ECs activated fibroblasts, induced cardiomyocyte hypertrophy, and impaired neuronal sprouting. Overexpression of ZBTB16 reversed these effects in senescent ECs and aged mice and reduced diastolic dysfunction. Mechanistic studies identified key downstream targets of ZBTB16, including nuclear receptor-interacting protein 1 (NRIP1). ZBTB16 suppressed NRIP1 expression, limiting fibroblast activation and pro-fibrotic signaling. ConclusionsZBTB16 is a key regulator of endothelial function, maintaining vascular niche homeostasis and mitigating aging-associated cardiac dysfunction. Its loss promotes EC senescence and pro-fibrotic signaling, contributing to diastolic dysfunction. Overexpression of ZBTB16 presents a potential therapeutic strategy for preserving cardiac function during aging. These findings establish a novel role for ZBTB16 in endothelial aging and cardiovascular disease prevention. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=78 SRC="FIGDIR/small/681100v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@1a56e2org.highwire.dtl.DTLVardef@13e23fforg.highwire.dtl.DTLVardef@ad681eorg.highwire.dtl.DTLVardef@8eca8b_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

Depletion of CX3CR1+ macrophages results in disrupted functionality and immune surveillance within epididymis and testis

A finely tuned immune regulation within the epididymis and testis is essential for male reproductive health. This balance is especially critical in the epididymis, where sperm mature and ascending infections frequently disrupt homeostasis, resulting in regionally different immune responses and potential long-term fertility impairments. We previously demonstrated that the epididymis harbors a region-specific immunological scaffold, with CX3CR1+ macrophages as the most prominent epithelium-associated immune cell population. Here, we established a transgenic mouse model to selectively deplete these intraepithelial CX3CR1+ macrophages within the epididymis, resulting in focal epithelial damage and impaired sperm maturation processes essential for proper sperm functionality. Additionally, a mild reduction of the testicular macrophage pool resulted in transient disruptions in spermatogenesis and steroidogenesis. Although the macrophage niche was repopulated after depletion, the newly recruited cells displayed altered phenotypes consistent with persistent sperm alterations. Following infection with uropathogenic Escherichia coli (UPEC), macrophage-depleted mice exhibited exacerbated immune responses - particularly in normally protected proximal epididymal regions - with earlier onset and more severe tissue damage. Transcriptomic analysis revealed a failure to restrain inflammatory responses, especially in genes involved in immune regulation and antibacterial defense, accompanied by elevated immune cell infiltration in infected macrophage-depleted mice. Overall, our findings confirm a crucial role for CX3CR1 macrophages in preserving epithelial integrity and modulating immune responses, supporting a stable tissue environment necessary for efficient organ function of both epididymis and testis. Significance statementMaintaining immune balance in the epididymis is essential for tissue health and protection against ascending infections. Using a transgenic mouse model that allows for selective depletion of CX3CR1 macrophages, this study examines their role in both the epididymis and testis under normal and infectious conditions. The results show that the removal of these macrophages causes localized epithelial damage, changes in immune cell make-up, and increased inflammation in the epididymis after bacterial infection, while also causing mild, reversible problems with spermatogenesis and steroid production in the testis. These findings support the idea that CX3CR1 macrophages contribute to region-specific immune regulation and epithelial stability--key features for keeping the tissue environment suitable for proper sperm development.

immunology↗

Deciphering human heart failure with preserved ejection fraction (HFpEF) at single cell resolution

BACKGROUNDHeart failure with preserved ejection fraction (HFpEF) is a complex and growing condition, representing over half of all heart failure cases. Despite its high morbidity and mortality, its heterogeneity and limited therapeutic options pose significant challenges. Understanding the molecular mechanisms driving HFpEF is essential for the development of new therapies to improve patient outcomes. METHODSWe performed single-nucleus RNA sequencing of nuclei obtained from endomyocardial biopsies of six patients with HFpEF. The obtained dataset was integrated with a dataset of 12 healthy human hearts and their transcriptomic differences were analyzed. RESULTSAfter quality control and integration of the datasets, nine major cardiac cell types were annotated. HFpEF cardiomyocytes were characterized by a reduction in genes associated with aerobic respiration and fatty acid metabolism and showed an upregulation of RHOA/ROCK1 signaling, which was validated using immunofluorescence staining in human HFpEF myocardial sections. Endothelial cells exhibited signs of increased apoptosis, SEMA3 signaling and signs of reduced VEGFA signaling as well as a reactivation of a fetal gene signature. In line with a prominent role of cardiac fibrosis in HFpEF, we observed increased signs of fibroblast activation and proliferation, and reduced signs of IFN{gamma} signaling in HFpEF which was most pronounced in activated fibroblasts. Treatment of human cardiac fibroblast with rhIFN{gamma} resulted in decreased collagen contents. Macrophages from HFpEF myocardium showed a pro-inflammatory transcriptomic signature and showed increased expression of MHC-II molecules. This was associated with signs of an increased IFN{gamma} response. CONCLUSIONOur results provide insights into the transcriptional diversity of HFpEF recapitulating structural, functional, and molecular hallmarks of the disease and provide mechanistic insights which might represent therapeutic targets and biomarkers to improve outcome of patients with HFpEF. CLINICAL PERSPECTIVEO_ST_ABSWhat is new?C_ST_ABSO_LIWe provide a single-nucleus RNA sequencing (snRNA-Seq) dataset from human HFpEF myocardium and demonstrate feasibility of snRNA-Seq from endomyocardial biopsies C_LIO_LIThe snRNA-Seq data confirms signs of known molecular hallmarks of HFpEF, such as metabolic changes, inflammation and fibrosis C_LIO_LIWe identify signs of regulating cellular mechanisms underlying these hallmarks, such as cytoskeleton remodeling via RhoA/ROCK1 in cardiomyocytes, and differential interferon gamma signaling in stromal and immune cells C_LI What are the clinical implications?O_LIWe provide several cell type-specific cellular mechanisms which might serve as biomarkers or therapeutic targets in the treatment of HFpEF C_LI

cell biology↗

STAT3 expression is reduced in cardiac pericytes in HFpEF and its loss reduces cellular adhesion and induces pericyte senescence

Heart failure with preserved ejection fraction (HFpEF) accounts for half of heart failure cases and is characterised by reduced pericyte coverage. While the contributions of other cardiac cell types to HFpEF are well-studied, the role of pericytes remains less understood. Using murine single-nucleus RNA sequencing to study cardiac pericytes in HFpEF, we identified reduced STAT3 expression as a hallmark of HFpEF pericytes. Mechanistic studies in vitro revealed that STAT3 deletion induces cellular senescence and impairs pericyte adhesion, recapitulating HFpEF-like characteristics. These findings suggest that STAT3 is crucial for maintaining pericyte homeostasis and highlight its reduction as a potential driver of pericyte loss, a defining feature of HFpEF.

cell biology↗

Exploring the Antifibrotic Potential of the heparan sulfate mimetic OTR4120: Insights from Preclinical Models

RationaleIdiopathic pulmonary fibrosis (IPF) is a debilitating lung disease characterized by excessive deposition of extracellular matrix (ECM), resulting in lung function impairment. Heparan sulfate mimetics (HSm) have been suggested to have potential antifibrotic effects by regulating ECM. This study aims to investigate the impact of a specific HSm named OTR4120 on fibrotic processes in ex vivo, in vitro and in vivo models. MethodsHuman Precision Cut Lung Slices (hPCLS) treated with a fibrotic cocktail alone or with OTR4120 were evaluated using second-harmonic imaging microscopy (SHIM) to assess collagen deposition. Human embryonic fibroblast WI-38 cell line and primary fibroblasts obtained from human donors were differentiated into myofibroblasts (MYF) using TGF-{beta}1 and treated with OTR4120 or a control vehicle. Gene expression analysis for MYF markers was performed using quantitative PCR (qPCR). Protein expression of MYF markers was evaluated using immunofluorescence techniques. Bulk-RNA sequencing analysis on WI-38 cells cultured under different experimental conditions was conducted. Finally, the therapeutic effects of OTR4120 on a bleomycin-induced fibrosis mouse model were investigated. ResultsSHIM analysis on OTR4120-treated hPCLS showed a decrease in collagen deposition. OTR4120 treatment of primary fibroblasts and WI-38 cells exposed to TGF-{beta}1 significantly reduced the expression of MYF markers. Bulk-RNA sequencing analysis on OTR4120-treated WI-38 cells showed significant impacts on fibrosis-related processes. Therapeutic application of OTR4120 in vivo to bleomycin-induced fibrosis mice resulted in enhanced fibrosis resolution. ConclusionOTR4120 has potential therapeutic benefits as an antifibrotic agent in the context of lung fibrosis. Further investigations are necessary to understand the precise mechanism through which OTR4120 exerts its antifibrotic effects.

cell biology↗