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Paneni, F.

Publications and source records attributed to Paneni, F..

3 recordsLinked to original sources

Stimulatrix: An open-source automated platform for high-throughput functional characterization of engineered contractile tissues

Engineered cardiac and skeletal muscle tissues suspended between flexible posts support disease modeling and pharmacology, yet their stimulation, longitudinal imaging and quantitative analysis often remain fragmented and labor-intensive. Here we present Stimulatrix, an open-source platform integrating automated video acquisition within a cell culture incubator, synchronized electrical stimulation and deep learning for longitudinal assessment of contractile tissues in multiwell plates. The platform quantifies tissue compaction, force generation and contraction kinetics with optional cloud processing reducing dependence on local GPU hardware. We demonstrate the workflow in cardiac tissues comprising human induced pluripotent stem cell-derived cardiomyocytes and cardiac fibroblasts, and in primary human skeletal muscle constructs. Force and kinetic measurements were benchmarked against manual annotations. Longitudinal profiling resolved responses to matrix composition and pacing regimens and tracked doxorubicin-associated loss of cardiac contractile force. Stimulatrix provides an accessible workflow for automated functional phenotyping of engineered muscle tissues.

bioengineering↗

Gut Microbiota Production of Phenylacetate Programs Vascular Niche Senescence and Drives Atherosclerosis

Vascular senescence is a key contributor to ageing-related diseases, including atherosclerosis. Initial intervention is based on aggressive management of traditional risk factors, yet microbial metabolites remain underestimated as modifiable factors. We recently identified phenylacetate (PAA), a gut microbiota-linked metabolite, as a potent accelerator of endothelial senescence, raising the question of its causal role in atherosclerosis. Here, we show that PAA promotes vascular niche senescence and perivascular adipose tissue (PVAT) dysfunction, associated with atherosclerosis in humans and mice. Furthermore, PAA administration to atherosclerosis-prone mice was sufficient to drive atherosclerosis without altering lipid profile. Mechanistically, we found that PAA induces senescence-messaging secretome, containing IL-6, from endothelial cells, which stimulates Notch1 and disrupts insulin signaling in adipocytes. Blocking the PAA-IL-6-Notch1 axis as well as senolytics rescued adipocyte senescence and dysfunction. Identification of the strong link between PAA and atherosclerosis opens new avenues for microbiome-targeted preventive and therapeutic strategies in ageing. HighlightsO_LIAge-dependent increase in gut microbial metabolite PAA causally promotes vascular niche senescence C_LIO_LIPAA indirectly accelerates PVAT senescence through endothelial senescence-messaging secretome C_LIO_LISASP upregulates Notch1 signaling, leading to PVAT dysfunction C_LIO_LISenolytic therapy restores PVAT function C_LIO_LIPAA-induced vascular niche senescence contributes to atherosclerosis progression C_LI

cell biology↗

Chromatin Remodeling by the Histone Methyltransferase SETD2 Drives Lipotoxic Injury in Cardiometabolic Heart Failure with Preserved Ejection Fraction

BackgroundCardiometabolic heart failure with preserved ejection fraction (cHFpEF) is highly prevalent and associates with a poor outcome. Pathological gene expression in heart failure is accompanied by changes in active histone marks without major alterations in DNA methylation. Histone 3 trimethylation at lysine 36 (H3k36me3) - a chromatin signature induced by the histone methyltransferase SETD2 - strongly correlates with changes in gene expression in human failing hearts; however, its role is poorly understood. Here we investigate the role of SETD2 in cHFpEF. MethodsMice with cardiomyocyte-specific deletion of SETD2 (c-SETD2-/-) were generated and subjected to high fat diet feeding and L-NAME treatment for 15 weeks to induce cHFpEF. Cardiac function and exercise tolerance were assessed by echocardiography and Treadmill exhaustion test. Chromatin immunoprecipitation assays (ChIP) were performed to investigate SETD2/H3k36me3 enrichment on gene promoters. SETD2 gain- and loss-of-function experiments were performed in cultured cardiomyocytes (CMs) exposed to palmitic acid (PA). SETD2 expression was also investigated in left ventricular (LV) myocardial specimens from patients with cHFpEF and control donors. ResultsSETD2 was upregulated in cHFpEF mouse hearts and its chromatin mark H3k36me3 was enriched on the promoter of sterol regulatory element-binding transcription factor 1 (SREBP1) gene. SETD2 activation in cHFpEF led to SREBP1 upregulation, triglyceride accumulation and lipotoxic damage. Of note, cardiomyocyte-specific deletion of SETD2 in mice prevented HFpEF-related hypertrophy, diastolic dysfunction and lung congestion while improving exercise tolerance. SETD2 deletion blunted H3K36me3 enrichment on SREBP1 promoter thus leading to a marked rewiring of the cardiac lipidome and restoration of autophagic flux. SETD2 depletion in PA-treated CMs prevented SREBP1 upregulation, whereas SETD2 overexpression recapitulated lipotoxic damage. Finally, SETD2 was upregulated in LV specimens from cHFpEF patients and its pharmacological inhibition by EZM0414 attenuated CM stiffness. ConclusionsTherapeutic modulation of SETD2/H3k36me3 axis might prevent lipotoxic injury and cardiac dysfunction in cHFpEF.

physiology↗