Aging is a risk factor for several chronic conditions, including intervertebral disc degeneration and associated back pain. Disc pathologies include loss of reticular-shaped nucleus pulposus cells, disorganization of annulus fibrosus lamellae, reduced disc height, and increased disc bulging. Sonic hedgehog, cytokeratin 19, and extracellular matrix proteins are markers of healthy disc.
View Article and Find Full Text PDFNat Cardiovasc Res
August 2024
Valve remodeling is a process involving extracellular matrix organization and elongation of valve leaflets. Here, through single-cell RNA sequencing of human fetal valves, we identified an elastin-producing valve interstitial cell (VIC) subtype (apolipoprotein E (APOE), elastin-VICs) spatially located underneath valve endothelial cells (VECs) sensing unidirectional flow. APOE knockdown in fetal VICs resulted in profound elastogenesis defects.
View Article and Find Full Text PDFValvular heart disease is a common cause of morbidity and mortality worldwide and has no effective medical therapy. Severe disease is managed with valve replacement procedures, which entail high health care-related costs and postprocedural morbidity and mortality. Robust ongoing research programs have elucidated many important molecular pathways contributing to primary valvular heart disease.
View Article and Find Full Text PDFBackground: Myxomatous valve disease (MVD) is the most common cause of mitral regurgitation, leading to impaired cardiac function and heart failure. MVD in a mouse model of Marfan syndrome includes valve leaflet thickening and progressive valve degeneration. However, the underlying mechanisms by which the disease progresses remain undefined.
View Article and Find Full Text PDFDuring development, macrophage subpopulations derived from hematopoietic progenitors take up residence in the developing heart. Embryonic macrophages are detectable at the early stages of heart formation in the nascent myocardium, valves and coronary vasculature. The specific subtypes of macrophages present in the developing heart reflect the generation of hematopoietic progenitors in the yolk sac, aorta-gonad-mesonephros, fetal liver, and postnatal bone marrow.
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