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Kudryashova, T. V.

Publications and source records attributed to Kudryashova, T. V..

5 recordsLinked to original sources

Lactate dehydrogenase-induced DNA Topoisomerase 1 is a novel regulator of smooth muscle cell proliferation and remodeling in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) manifests by increased proliferation and survival of pulmonary vascular cells in small pulmonary arteries (PAs), PA remodeling and unresolved increase of PA pressure. PA smooth muscle cells (PASMCs) in PAH undergo metabolic shift to glycolysis resulting in over-production of lactate, hyper-proliferation, and apoptosis resistance, but the mechanisms are not completely understood. By using lung tissues and pulmonary vascular cells from PAH and non-diseased human lungs, unbiased proteomics, network analysis, and gain-and-loss of function approaches, we here report that up-regulation of lactate dehydrogenase A (LDHA)-lactate axis promotes PASMC-specific over-lactylation and consequent over-accumulation of DNA topoisomerase 1 (TOP1) in small remodeled PAs from PAH lungs, leading to the up-regulation of Akt-mechanistic target of rapamycin 1 (mTORC1) signaling, hyper-proliferation, and reduced apoptosis. Smooth muscle-specific LDHA knockdown prevented, and Ldha inhibitor oxamate reversed SU5416/hypoxia-induced TOP1 accumulation, pulmonary vascular remodeling, and pulmonary hypertension (PH) in mice. Pharmacological inhibition of TOP1 with indotecan suppressed Akt-mTORC1, decreased proliferation, induced apoptosis in human PAH, but not control PASMCs, and reversed PA remodeling, PH, and RV dysfunction in rats. Collectively, these data provide a novel mechanistic link from LDHA-driven lactate over-production through lactylation and overaccumulation of TOP1, to the up-regulation of Akt-mTORC1, hyper-proliferation and apoptosis resistance of PASMCs, pulmonary vascular remodeling, and PH, and identify TOP1 as a new potentially attractive molecular target for the remodeling-focused therapeutic intervention. Take-home messageLDHA-lactate-induced over-lactylation and overaccumulation of Topoisomerase 1 (TOP1) promotes pulmonary artery smooth muscle cell hyper-proliferation, remodeling, and pulmonary arterial hypertension, which are reversed by TOP1 inhibitor indotecan.

cell biology↗

Non-canonical HIPPO-MST1/2 promotes hyper-proliferation of pulmonary vascular cells through CDC20

HIPPO components mammalian Ste20-like protein kinases 1 and 2 (MST1/2) are well described growth suppressors. However, in pulmonary arterial hypertension (PAH), MST1/2 switch their roles and become pro-proliferative and pro-survival molecules, supporting hyper-proliferation of pulmonary artery (PA) smooth muscle cells (PASMCs) and adventitial fibroblasts (PAAFs), remodeling of small PAs, and pulmonary hypertension. Here, we report that MST1/2 promotes hyper-proliferation and apoptosis resistance of human PAH PASMCs and PAAFs by up-regulating cell division cycle protein 20 (CDC20), establishing novel link between HIPPO-MST1/2 and cell cycle regulation in PAH. Authors Contributionsconception and design of the work (EAG, SSP, TVK); acquisition, analysis, and interpretation of data (TD, IZ, LJ, SOO, AP, TA, DL, DG, JRG, PJW, HD, TK); drafting and editing the manuscript (EAG, SSP, TVK, JRG, PJW).

cell biology↗

PAI-1 Deficiency Drives Pulmonary Vascular Smooth Muscle Remodeling and Pulmonary Hy-pertension

Pulmonary arterial hypertension (PAH) is a progressive and potentially a rapidly fatal disease characterized by vasoconstriction and remodeling of small pulmonary arteries (PA) leading to increased pulmonary vascular resistance and right heart failure. Central to the remodeling process is a switch of the smooth muscle cells in small PAs (PASMC) to a proliferative, apoptosis-resistant phenotype. There is reason to suspect that the plasminogen activator system may play an important role in the remodeling program in PAH based on its roles in vascular post-injury restenosis, fibrosis, angiogenesis and tumorigenesis. Plasminogen activator inhibitor-1 (PAI-1) is the primary physiological inhibitor of the plasminogen activators - urokinase-type and tissue-type (uPA and tPA, respectively). Immunohisto- chemical and immunoblot analyses revealed that PAI-1 was deficient in smooth muscle areas of small remodeled PAs and early-passage PASMC from subjects with PAH compared to non-PAH controls. PAI1-/- male and female mice developed spontaneous pulmonary vascular remodeling and pulmonary hypertension (PH) as evidenced by significant increase in PA medial thickness, systolic right ventricular pressure, and right ventricular hypertrophy. Lastly, the uPA inhibitors upamostat (WX-671) and amiloride analog BB2-30F down-regulated mTORC1 and SMAD3, restored PAI-1 levels, reduced proliferation, and induced apoptosis in human PAH PASMC. We examined the effect of inhibition of uPA catalytic activity by BB2-30F on the development of SU5416/Hypoxia (SuHx)-induced PH in mice. Vehicletreated SuHx-exposed mice had up-regulated mTORC1 in small PAs, developed pulmonary vascular remodeling and PH, as evidenced by significant increase of PA MT, sRVP, RV hypertrophy, and a significant decrease in the pulmonary artery acceleration time/pulmonary ejection time (PAAT/PET) ratio compared to age- and sex-matched normoxia controls, whereas BB2-30F-treated group was protected from all these pathological changes. Taken together, our data strongly suggest that PAI-1 down- regulation in PASMC from human PAH lungs promotes PASMC hyper-proliferation, remodeling, and spontaneous PH due to unopposed uPA activation. Further studies are needed to determine the potential benefits of targeting the PAI-1/uPA imbalance to attenuate the progression and/or reverse pulmonary vascular remodeling and PH.

cell biology↗

RAB7 deficiency impairs pulmonary artery endothelial function and promotes pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with limited treatment options. Endothelial dysfunction plays a central role in development and progression of PAH, yet the underlying mechanisms are incompletely understood. The endosome-lysosome system is important to maintain cellular health and the small GTPase RAB7 regulates many functions of this system. Here, we explored the role of RAB7 in endothelial cell (EC) function and lung vascular homeostasis. We found reduced expression of RAB7 in ECs from PAH patients. Endothelial haploinsufficiency of RAB7 caused spontaneous PH in mice. Silencing of RAB7 in ECs induced broad changes in gene expression revealed via RNA sequencing and RAB7 silenced ECs showed impaired angiogenesis, expansion of a senescent cell fraction, combined with impaired endolysosomal trafficking and degradation, which suggests inhibition of autophagy at the pre-degradation level. Further, mitochondrial membrane potential and oxidative phosphorylation were decreased, and glycolysis was enhanced. Treatment with the RAB7 activator ML-098 reduced established PH in chronic hypoxia/SU5416 rats. In conclusion, we demonstrate here for the first time the fundamental impairment of EC function by loss of RAB7 that leads to PH and show RAB7 activation as a potential therapeutic strategy in a preclinical model of PH.

physiology↗

TSC2-extracellular matrix crosstalk controls pulmonary vascular proliferation and pulmonary hypertension

Increased proliferation and survival of resident cells in small pulmonary arteries (PA) are important drivers of pulmonary hypertension (PH). Tuberous sclerosis complex 2 (TSC2) is a negative regulator of mTOR complex 1 and cell growth. Here we show that TSC2 is deficient in small remodeled PA/PA vascular smooth muscle cells (PAVSMC) from human PAH and experimental PH lungs. TSC2 deficiency was reproduced in vitro by maintaining PAVSMC on pathologically stiff substrates and was required for stiffness-induced proliferation, accumulation of transcriptional co-activators YAP/TAZ and up-regulation of mTOR. Depletion of TSC2 reproduced PH features in vitro in human PAVSMC and in vivo in SM22-Tsc2+/- mice. TSC2 loss in PAVSMC was supported by YAP and led to the up-regulation of YAP/TAZ and mTOR via modulating the extracellular matrix (ECM) composition. ECM, produced by TSC2-deficient PAVSMC, promoted growth of non-diseased PA adventitial fibroblasts and PAVSMC, which, in turn, was prevented by 5{beta}1 integrin receptor antagonist ATN161. In vitro, molecular and pharmacological (SRT2104) restoration of TSC2 down-regulated YAP/TAZ, mTOR, and ECM production, inhibited proliferation and induced apoptosis in human PAH PAVSMC. In vivo, orally administrated SRT2104 restored TSC2, resolved pulmonary vascular remodeling, PH, and improved right heart in two rodent models of PH. Thus, PAVSMC TSC2 is a critical integrator of ECM composition and stiffness with pro-proliferative signaling and PH, and the restoration of functional TSC2 could be an attractive therapeutic option to treat PH. One Sentence SummaryTSC2 acts as mechanosensor and mechanotransducer, integrating ECM composition and stiffness with pro-proliferative signaling in pulmonary vasculature; its deficiency in PA vascular smooth muscle cells results in ECM remodeling, hyper-proliferation and pulmonary hypertension, which could be reversed by pharmacological restoration of functional TSC2.

molecular biology↗