MTert induction in p21-positive cells counteracts capillary rarefaction and pulmonary emphysema
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ABSTRACT:
SUBMITTER: Larissa Lipskaia
PROVIDER: S-SCDT-10_1038-S44319-023-00041-1 | biostudies-other |
REPOSITORIES: biostudies-other
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Project description:Lung diseases develop when telomeres are shortened beyond a critical point. We have constructed a mouse model in which the catalytic subunit of telomerase (mTert), or its catalytically inactive form (mTertCI), is expressed from the p21Cdkn1a promoter. We found that this particular expression of mTert reduces senescence of endothelial cells (EC) in lungs of aged mice, as well as emphysema and pulmonary perivascular fibrosis. We also show that mTert counteracts the decline in capillary density in aged mice and promotes the maintenance of high numbers of Cd34+ cells, identified as a subclass of endothelial cells with proliferative capacity. In line with these results, young p21+/Tert mice treated with a VEGF receptor inhibitor combined with hypoxia are also protected against senescence and emphysema induced by this treatment. The catalytic activity of mTert is required for all the effects observed. However, and unexpectedly, we found that both mTert and mTertCI expression significantly reduced p21 levels in the lungs of aged mice. mTert thus protects against age-related and induced loss of capillary vessels and subsequent lung emphysema.
2023-06-29 | GSE165218 | GEO
Project description:mTert induction in p21-positive cells counteracts capillary rarefaction and pulmonary emphysema
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Project description:In diabetes mellitus type 2, capillary rarefaction plays a pivotal role in the pathogenesis of end-organ damage. We investigated retinal capillary density in patients with early disease.This cross-sectional study compares retinal capillary rarefaction determined by intercapillary distance (ICD) and capillary area (CapA), measured non-invasively and in vivo by scanning laser Doppler flowmetry, in 73 patients with type 2 diabetes, 55 healthy controls and 134 individuals with hypertension stage 1 or 2.In diabetic patients, ICD was greater (23.2±5.5 vs 20.2±4.2, p = 0.013) and CapA smaller (1592±595 vs 1821±652, p = 0.019) than in healthy controls after adjustment for differences in cardiovascular risk factors between the groups. Compared to hypertensive patients, diabetic individuals showed no difference in ICD (23.1±5.8, p = 0.781) and CapA (1556±649, p = 0.768).In the early stage of diabetes type 2, patients showed capillary rarefaction compared to healthy individuals.
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