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Firouzi, F.

Publications and source records attributed to Firouzi, F..

3 recordsLinked to original sources

Fundamentals of Vaping-Associated Pulmonary Injury Leading to Severe Respiratory Distress

Vaping of flavored liquids has been touted as safe alternative to traditional cigarette smoking with decreased health risks. The popularity of vaping has dramatically increased over the last decade, particularly among teenagers who incorporate vaping into their daily life as a social activity. Despite widespread and increasing adoption of vaping among young adults there is little information on long term consequences of vaping and potential health risks. This study demonstrates Vaping-Induced Pulmonary Injury (VAPI) using commercial JUUL pens with flavored vape juice using an inhalation exposure murine model. Profound pathological changes to upper airway, lung tissue architecture, and cellular structure are evident within 9 weeks of exposure. Marked histologic changes include increased parenchyma tissue density, cellular infiltrates proximal to airway passages, alveolar rarefaction, increased collagen deposition, and bronchial thickening with elastin fiber disruption. Transcriptional reprogramming includes significant changes to gene families coding for xenobiotic response, glycerolipid metabolic processes, and oxidative stress. Cardiac contractile performance for systemic output is moderately but significantly impaired, and the shows severe pulmonary side structural remodeling with chamber enlargement. This VAPI model with pulmonary circuit failure demonstrates mechanistic underpinnings of vaping-related pathologic injury.

molecular biology↗

Human CardioChimeras: Creation of a Novel \"Next Generation\" Cardiac Cell

BackgroundCardioChimeras (CCs) produced by fusion of murine c-kit+ cardiac interstitial cells (cCIC) with mesenchymal stem cells (MSCs) promote superior structural and functional recovery in a mouse model of myocardial infarction (MI) compared to either precursor cell alone or in combination. Creation of human CardioChimeras (hCC) represents the next step in translational development of this novel cell type, but new challenges arise when working with cCICs isolated and expanded from human heart tissue samples. The objective of the study was to establish a reliable cell fusion protocol for consistent optimized creation of hCCs and characterize fundamental hCC properties.\n\nMethods and ResultsCell fusion was induced by incubating human cCICs and MSCs at a 2:1 ratio with inactivated Sendai virus. Hybrid cells were sorted into 96-well microplates for clonal expansion to derive unique cloned hCCs, which were then characterized for various cellular and molecular properties. hCCs exhibited enhanced survival relative to the parent cells and promoted cardiomyocyte survival in response to serum deprivation in vitro.\n\nConclusionsThe generation of hCC is demonstrated and validated in this study, representing the next step toward implementation of a novel cell product for therapeutic development. Feasibility of creating human hybrid cells prompts consideration of multiple possibilities to create novel chimeric cells derived from cells with desirable traits to promote healing in pathologically damaged myocardium.\n\nClinical PerspectiveO_LI\"Next generation\" cell therapeutics will build upon initial findings that demonstrate enhanced reparative action of combining distinct cell types for treatment of cardiomyopathic injury.\nC_LIO_LIDifferential biological properties of various cell types are challenging for optimization of delivery, engraftment, persistence, and synergistic action when used in combination.\nC_LIO_LICreation of a novel hybrid cell called a CardioChimera overcomes limitations inherent to use of multiple cell types.\nC_LIO_LICardioChimeras exhibit unique properties relative to either parental cell anticipated to be advantageous in cellular therapeutic applications.\nC_LIO_LICardioChimeras have now been created and characterized using cells derived from human heart tissue, advancing initial proof of concept previously demonstrated with mice.\nC_LIO_LICardioChimeras represent an engineered solution that can be implemented as a path forward for improving the outcome of myocardial cell therapy.\nC_LI

cell biology↗

Tetraploidy in rodent cardiac stem cells confers enhanced biological properties

Ploidy for cardiomyocytes is well described but remains obscure in cardiac interstitial cells (CICs). Ploidy of c-kit+CICs were assessed using a combination of confocal, karyotypic, and flow cytometric assessments coupled with molecular and bioinformatic analyses. Fundamental differences were found between cultured rodent (rat, mouse) c-kit+CICs possessing mononuclear tetraploid (4n) content versus large mammal (human, swine) with mononuclear diploid (2n) content. In-situ analysis, confirmed with fresh isolates, revealed diploid content in c-kit+CICs from human and a mixture of diploid and tetraploid nuclei in mouse. Molecular assessment of the p53 signaling pathway provides a plausible explanation for escape from replicative senescence in rodent but not human ckit+CICs. Single cell transcriptional profiling reveals distinctions between diploid versus tetraploid populations in mouse ckit+CICs, alluding to functional divergences. Collectively, these data reveal fundamental species-specific biological differences in c-kit+CICs that could account for challenges in extrapolation of myocardial preclinical studies from rodent to large animal models.

cell biology↗