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1.
Dalton Trans ; 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38912924

ABSTRACT

DNA being the necessary element in cell regeneration, controlled cellular apoptosis via DNA binding/cleaving is considered an approach to combat cancer cells. The widely prescribed metallodrug cisplatin has shown interactions with the guanine-N7 center, and a plethora of complexes are continually developed to enhance crosslinking properties as well as covalent and non-covalent interactions. Two pentadentate ligands, L1 (1-(6-(1H-benzo[d]imidazol-2-yl)pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine) and L2 (1-(6-(1-methyl-1H-benzo[d]imidazol-2-yl)pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)methanamine), were synthesized together with their respective copper(II) complexes [1](ClO4)2 and [2](ClO4)2, which crystallized in a trigonal bipyramidal fashion. Different analytical and spectroscopic methods confirmed their formation, and their redox behaviour was also examined. The interactions of salmon sperm DNA (ss-DNA) with these two complexes were explored using absorbance spectroscopy, and they both exhibited a binding affinity (Kb) of ∼104 M-1. Fluorescence quenching experiments with ethidium bromide (EB)-bound DNA (EB-DNA) were also performed, and Stern-Volmer constant (KSV) values of 6.93 × 103 and 2.34 × 104 M-1 for [1](ClO4)2 and [2](ClO4)2, respectively, were obtained. Furthermore, DNA conformational changes due to the interactions of both complexes were validated via circular dichroism. We also assessed the DNA cleavage property of these complexes, which resulted in the linearization of circular plasmid DNA. This finding was supported by studying the growth of MDA-MB-231 breast cancer cells upon treatment with both Cu(II) complexes; IC50 values of 5.34 ± 1.02 µM and 0.83 ± 0.18 µM were obtained for [1](ClO4)2 and [2](ClO4)2, respectively. This validates their affinity towards DNA, and these insights can be further utilized for non-platinum based economical metallodrug development based on first row transition metals.

2.
Exp Cell Res ; 438(1): 114026, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38604522

ABSTRACT

The emergence of AR-V7, a truncated isoform of AR upon androgen deprivation therapy treatment, leads to the development of castration resistant prostate cancer (CRPC). Understanding mechanisms that regulate AR-V7 expression is critical for developing newer therapeutic strategies. In this study, we have investigated the regulation of AR-V7 during cell cycle and identified a distinct pattern of periodic fluctuation, peaking during G2/M phase. This fluctuation correlates with the expression of Cdc-2 like kinase 1 (CLK1) and phosphorylated serine/arginine-rich splicing factor 1 (p-SRSF1) during these phases, pointing towards their role in AR-V7 generation. Functional assays reveal that CLK1 knockdown prolongs the S phase, leading to altered cell cycle distribution and increased accumulation of AR-V7 and pSRSF1 in G1/S phase. Conversely, CLK1 overexpression rescues AR-V7 and p-SRSF1 levels in the G2/M phase, consistent with observed cell cycle alterations upon AR-V7 knockdown and overexpression in CRPC cells. Furthermore, overexpression of kinase-deficient CLK1 mutant leads to diminished AR-V7 levels during G2/M, underlining the essential contribution of CLK1's kinase activity in modulating AR-V7 expression. Collectively, our findings, for the first time, show periodic regulation of AR-V7 expression, its effect on cell cycle progression and the critical role of CLK1-pSRSF1 axis in modulating AR-V7 expression throughout the cell cycle.


Subject(s)
G2 Phase Cell Cycle Checkpoints , Prostatic Neoplasms, Castration-Resistant , Receptors, Androgen , Humans , Male , Cell Line, Tumor , Cell Proliferation/genetics , G2 Phase/genetics , G2 Phase Cell Cycle Checkpoints/genetics , Gene Expression Regulation, Neoplastic , Phosphorylation , Prostatic Neoplasms, Castration-Resistant/genetics , Prostatic Neoplasms, Castration-Resistant/pathology , Prostatic Neoplasms, Castration-Resistant/metabolism , Protein Isoforms/genetics , Protein Isoforms/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Protein-Tyrosine Kinases/metabolism , Protein-Tyrosine Kinases/genetics , Receptors, Androgen/metabolism , Receptors, Androgen/genetics , Serine-Arginine Splicing Factors/metabolism , Serine-Arginine Splicing Factors/genetics
3.
JACC Basic Transl Sci ; 9(1): 120-144, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38362345

ABSTRACT

Clonal expansion refers to the proliferation and selection of advantageous "clones" that are better suited for survival in a Darwinian manner. In recent years, we have greatly enhanced our understanding of cell clonality in the cardiovascular context. However, our knowledge of the underlying mechanisms behind this clonal selection is still severely limited. There is a transpiring pattern of clonal expansion of smooth muscle cells and endothelial cells-and, in some cases, macrophages-in numerous cardiovascular diseases irrespective of their differing microenvironments. These findings indirectly suggest the possible existence of stem-like vascular cells which are primed to respond during disease. Subsequent clones may undergo further phenotypic changes to adopt either protective or detrimental roles. By investigating these clone-forming vascular cells, we may be able to harness this inherent clonal nature for future therapeutic intervention. This review comprehensively discusses what is currently known about clonal expansion across the cardiovascular field. Comparisons of the clonal nature of vascular cells in atherosclerosis (including clonal hematopoiesis of indeterminate potential), pulmonary hypertension, aneurysm, blood vessel injury, ischemia- and tumor-induced angiogenesis, and cerebral cavernous malformations are evaluated. Finally, we discuss the potential clinical implications of these findings and propose that proper understanding and specific targeting of these clonal cells may provide unique therapeutic options for the treatment of these cardiovascular conditions.

4.
Semin Cell Dev Biol ; 155(Pt C): 3-15, 2024 03 01.
Article in English | MEDLINE | ID: mdl-37316416

ABSTRACT

Smooth muscle cells, endothelial cells and macrophages display remarkable heterogeneity within the healthy vasculature and under pathological conditions. During development, these cells arise from numerous embryological origins, which confound with different microenvironments to generate postnatal vascular cell diversity. In the atherosclerotic plaque milieu, all these cell types exhibit astonishing plasticity, generating a variety of plaque burdening or plaque stabilizing phenotypes. And yet how developmental origin influences intraplaque cell plasticity remains largely unexplored despite evidence suggesting this may be the case. Uncovering the diversity and plasticity of vascular cells is being revolutionized by unbiased single cell whole transcriptome analysis techniques that will likely continue to pave the way for therapeutic research. Cellular plasticity is only just emerging as a target for future therapeutics, and uncovering how intraplaque plasticity differs across vascular beds may provide key insights into why different plaques behave differently and may confer different risks of subsequent cardiovascular events.


Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , Humans , Cell Plasticity , Endothelial Cells/metabolism , Atherosclerosis/genetics , Atherosclerosis/metabolism , Atherosclerosis/pathology , Plaque, Atherosclerotic/genetics , Plaque, Atherosclerotic/metabolism , Plaque, Atherosclerotic/pathology , Macrophages/metabolism
5.
bioRxiv ; 2023 Oct 03.
Article in English | MEDLINE | ID: mdl-37873248

ABSTRACT

Atherosclerosis is a chronic inflammatory disease which is driven in part by the aberrant trans -differentiation of vascular smooth muscle cells (SMCs). No therapeutic drug has been shown to reverse detrimental SMC-derived cell phenotypes into protective phenotypes, a hypothesized enabler of plaque regression and improved patient outcome. Herein, we describe a novel function of colchicine in the beneficial modulation of SMC-derived cell phenotype, independent of its conventional anti-inflammatory effects. Using SMC fate mapping in an advanced atherosclerotic lesion model, colchicine induced plaque regression by converting pathogenic SMC-derived macrophage-like and osteoblast-like cells into protective myofibroblast-like cells which thickened, and thereby stabilized, the fibrous cap. This was dependent on Notch3 signaling in SMC-derived plaque cells. These findings may help explain the success of colchicine in clinical trials relative to other anti-inflammatory drugs. Thus, we demonstrate the potential of regulating SMC phenotype in advanced plaque regression through Notch3 signaling, in addition to the canonical anti-inflammatory actions of drugs to treat atherosclerosis.

6.
bioRxiv ; 2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37905061

ABSTRACT

Background: Cholesterol-loading of mouse aortic vascular smooth muscle cells (mVSMCs) downregulates miR-143/145, a master regulator of the contractile state downstream of TGFß signaling. In vitro, this results in transitioning from a contractile mVSMC to a macrophage-like state. This process likely occurs in vivo based on studies in mouse and human atherosclerotic plaques. Objectives: To test whether cholesterol-loading reduces VSMC TGFß signaling and if cholesterol efflux will restore signaling and the contractile state in vitro and in vivo. Methods: Human coronary artery (h)VSMCs were cholesterol-loaded, then treated with HDL (to promote cholesterol efflux). For in vivo studies, partial conditional deletion of Tgfßr2 in lineage-traced VSMC mice was induced. Mice wild-type for VSMC Tgfßr2 or partially deficient (Tgfßr2+/-) were made hypercholesterolemic to establish atherosclerosis. Mice were then treated with apoA1 (which forms HDL). Results: Cholesterol-loading of hVSMCs downregulated TGFß signaling and contractile gene expression; macrophage markers were induced. TGFß signaling positively regulated miR-143/145 expression, increasing Acta2 expression and suppressing KLF4. Cholesterol-loading localized TGFß receptors into lipid rafts, with consequent TGFß signaling downregulation. Notably, in cholesterol-loaded hVSMCs HDL particles displaced receptors from lipid rafts and increased TGFß signaling, resulting in enhanced miR-145 expression and decreased KLF4-dependent macrophage features. ApoA1 infusion into Tgfßr2+/- mice restored Acta2 expression and decreased macrophage-marker expression in plaque VSMCs, with evidence of increased TGFß signaling. Conclusions: Cholesterol suppresses TGFß signaling and the contractile state in hVSMC through partitioning of TGFß receptors into lipid rafts. These changes can be reversed by promotion of cholesterol efflux, consistent with evidence in vivo.

7.
Clin Ther ; 45(11): 1047-1054, 2023 11.
Article in English | MEDLINE | ID: mdl-37709601

ABSTRACT

PURPOSE: Despite an increase in treatment options, and substantial reductions in cardiovascular mortality over the past half-century, atherosclerosis remains the most prevalent cause of premature mortality worldwide. The development of innovative new therapies is crucial to further minimize atherosclerosis-related deaths. The diverse array of cell phenotypes derived from vascular smooth muscle cells (SMCs) and macrophages within atherosclerotic plaques are increasingly becoming recognized for their beneficial and detrimental roles in plaque stability and disease burden. This review explores how contemporary transcriptomics and fate-mapping studies have revealed vascular cell plasticity as a relatively unexplored target for therapeutic intervention. METHODS: Recent literature for this narrative review was obtained by searching electronic databases (ie, Google Scholar, PubMed). Additional studies were sourced from reference lists and the authors' personal databases. FINDINGS: The lipid-rich and inflammatory plaque milieu induces SMC phenotypic switching to both beneficial and detrimental phenotypes. Likewise, macrophage heterogeneity increases with disease burden to a variety of pro-inflammatory and anti-inflammatory activation states. These vascular cell phenotypes are determinants of plaque structure stability, and it is therefore highly likely that they influence clinical outcomes. Development of clinical treatments targeting deleterious phenotypes or promoting pro-healing phenotypes remains in its infancy. However, existing treatments (statins) have shown beneficial effects toward macrophage polarization, providing a rationale for more targeted approaches. In contrast, beneficial SMC phenotypic modulation with these pharmacologic agents has yet to be achieved. The range of modulated vascular cell phenotypes provides a multitude of novel targets and the potential to reduce future adverse events. IMPLICATIONS: Vascular cell phenotypic heterogeneity must continue to be explored to lower cardiovascular events in the future. The rapidly increasing weight of evidence surrounding the role of SMC plasticity and macrophage polarity in plaque vulnerability provides a strong foundation upon which development of new therapeutics must follow. This approach may prove to be crucial in reducing cardiovascular events and improving patient benefit in the future.


Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , Humans , Muscle, Smooth, Vascular/metabolism , Cell Plasticity , Atherosclerosis/drug therapy , Macrophages , Phenotype
8.
Alzheimers Dement (Amst) ; 15(1): e12395, 2023.
Article in English | MEDLINE | ID: mdl-36911359

ABSTRACT

Introduction: We conducted a systematic review and meta-analysis to review the relationship between midlife dyslipidemia and lifetime incident dementia. Methods: The databases Medline, Embase, Scopus, Web of Science, and Cochrane were searched from inception to February 20, 2022. Longitudinal studies examining the relationship between midlife lipid levels on dementia, dementia subtypes, and/or cognitive impairment were pooled using inverse-variance weighted random-effects meta-analysis. Results: Seventeen studies (1.2 million participants) were included. Midlife hypercholesterolemia was associated with increased incidence of mild cognitive impairment (effect size [ES] = 2.01; 95% confidence interval [CI] 1.19 to 2.84; I2 = 0.0%) and all-cause dementia (ES = 1.14; 95% CI: 1.07 to 1.21; I2 = 0.0%). Each 1 mmol/L increase in low-density lipoprotein was associated with an 8% increase (ES = 1.08, 95% CI: 1.03 to 1.14; I2 = 0.3%) in incidence of all-cause dementia. Discussion: Midlife dyslipidemia is associated with an increased risk of cognitive impairment in later life.

9.
Adv Drug Deliv Rev ; 194: 114709, 2023 03.
Article in English | MEDLINE | ID: mdl-36690300

ABSTRACT

Atherosclerosis, a chronic cardiovascular disease caused by plaque development in arteries, remains a leading cause of morbidity and mortality. Atherosclerotic plaques are characterized by the expression and regulation of key molecules such as cell surface receptors, cytokines, and signaling pathway proteins, potentially facilitating precise diagnosis and treatment on a molecular level by specifically targeting the characteristic molecules. In this review, we highlight the recent progress in the past five years on developing molecularly targeted nanomedicine for imaging detection and treatment of atherosclerosis with the use of inorganic nanoparticles. Through targeted delivery of imaging contrast nanoparticles to specific molecules in atherogenesis, atherosclerotic plaque development at different stages could be identified and monitored via various molecular imaging modalities. We also review molecularly targeted therapeutic approaches that target and regulate molecules associated with lipid regulation, inflammation, and apoptosis. The review is concluded with discussion on current challenges and future development of nanomedicine for atherosclerotic diagnosis and treatment.


Subject(s)
Atherosclerosis , Nanoparticles , Plaque, Atherosclerotic , Humans , Nanomedicine/methods , Atherosclerosis/drug therapy , Plaque, Atherosclerotic/metabolism , Nanoparticles/therapeutic use , Drug Delivery Systems
10.
ACS Sustain Chem Eng ; 10(33): 10858-10869, 2022 Aug 22.
Article in English | MEDLINE | ID: mdl-36035440

ABSTRACT

Acetate is emerging as a promising feedstock for biorefineries as it can serve as an alternate carbon source for microbial cell factories. In this study, we expressed acetyl-CoA synthase in Yarrowia lipolytica PSA02004PP, and the recombinant strain grew on acetate as the sole carbon source and accumulated succinic acid or succinate (SA). Unlike traditional feedstocks, acetate is a toxic substrate for microorganisms; therefore, the recombinant strain was further subjected to adaptive laboratory evolution to alleviate toxicity and improve tolerance against acetate. At high acetate concentrations, the adapted strain Y. lipolytica ACS 5.0 grew rapidly and accumulated lipids and SA. Bioreactor cultivation of ACS 5.0 with 22.5 g/L acetate in a batch mode resulted in a maximum cell OD600 of 9.2, with lipid and SA accumulation being 0.84 and 5.1 g/L, respectively. However, its fed-batch cultivation yielded a cell OD600 of 23.5, SA titer of 6.5 g/L, and lipid production of 1.5 g/L with an acetate uptake rate of 0.2 g/L h, about 2.86 times higher than the parent strain. Cofermentation of acetate and glucose significantly enhanced the SA titer and lipid accumulation to 12.2 and 1.8 g/L, respectively, with marginal increment in cell growth (OD600: 26.7). Furthermore, metabolic flux analysis has drawn insights into utilizing acetate for the production of metabolites that are downstream to acetyl-CoA. To the best of our knowledge, this is the first report on SA production from acetate by Y. lipolytica and demonstrates a path for direct valorization of sugar-rich biomass hydrolysates with elevated acetate levels to SA.

11.
Bioresour Technol ; 358: 127381, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35644452

ABSTRACT

Bread is Europe's most wasted food, and the second most wasted food after potatoes in UK. Bread waste (BW) is a clean source of high-quality fermentable sugars. In this study, the potential of Enterobacter ludwigii to accumulate 2,3-butanediol (BDO) from BW was evaluated. Initially, the optimal inoculum size and yeast extract concentration were determined, followed by extraction of sugars from BW using acid and enzymatic hydrolysis. A glucose yield of 330-530 g/kg BW was obtained, and the sugars released were utilised for BDO production by E. ludwigii. The fed-batch cultivation using pure glucose and glucose rich hydrolysates from acid and enzymatic hydrolysis resulted in BDO titres of 144.5, 135.4, and 138.8 g/L, after 96 h, with yield of 0.47, 0.42 and 0.48 g/g yield, respectively. The innovation of the work is valorisation of BW to BDO with a circular biorefining approach and thus, reducing BW disposal and associated environmental burden.


Subject(s)
Refuse Disposal , Bread , Butylene Glycols , Fermentation , Glucose
12.
J Inorg Biochem ; 233: 111866, 2022 08.
Article in English | MEDLINE | ID: mdl-35636303

ABSTRACT

Mononuclear cobalt(II) complexes [CoII(L1)Cl2]; 1, [CoII(L1)(bpy)Cl]PF6; 2, [CoII(L1)(phen)Cl]PF6; 3 and [CoII(L2)Cl2]; 4 (where L1 = N,N-bis(pyridin-2-ylmethyl)aniline, L2 = (2,4,6-trimethyl-N,N-bis(pyridin-2-ylmethyl)aniline, bpy = 2,2/-bipyridine, phen = 1,10-phenanthroline) were synthesized and characterized by different analytical and spectroscopic methods. All the complexes were structurally identified by single-crystal X-ray crystallography. Penta-coordinated complex 1 adopted distorted trigonal bipyramidal and hexacoordinated complexes 2 and 3 having distorted octahedral geometry whereas tetra-coordinated complex 4 has distorted tetrahedral geometry. The interactions of salmon sperm DNA (ss-DNA) with complexes (1-4) were investigated by absorbance, fluorescence spectroscopy and molecular docking studies. All the complexes are very susceptible to DNA binding and the binding affinity (Kb) follows the order 3 (2.05 × 104 M -1) > 4 (1.40 × 104 M -1) > 2 (1.36 × 104 M -1) > 1 (1.34 × 104 M -1) indicating they have superior DNA binding ability. The Stern-Volmer constant (Ksv) ranges from 1.10 × 104 M -1 to 1.95 × 104 M -1 suggesting weak or moderate binding with DNA. DNA cleavage study in plasmid DNA reveals very efficient DNA cleavage factors even in the absence of any external agents. Using multiple biochemical assays, we have demonstrated that 1-4 induces apoptosis of human cancer cells with IC50 values of 26.48 ± 1.45 µM, 10.89 ± 0.55 µM, 7.63 ± 0.4 µM and 37.67 ± 2.06 µM, respectively in A549 lung adenocarcinoma cells and 14.45 ± 0.73 µM, 1.97 ± 0.1 µM, 0.98 ± 0.05 µM and 24.43 ± 1.22 µM, respectively in MDA-MB-231 breast adenocarcinoma cells.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Neoplasms , Aniline Compounds , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cobalt/chemistry , Cobalt/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Copper/chemistry , Crystallography, X-Ray , DNA/chemistry , Humans , Ligands , Molecular Docking Simulation
13.
Dalton Trans ; 51(18): 7084-7099, 2022 May 10.
Article in English | MEDLINE | ID: mdl-35357373

ABSTRACT

Mononuclear Co(II) complexes [CoII(L)Cl2]; 1, [CoII(L)(bpy)Cl]PF6; 2, [CoII(L)(phen)Cl]PF6; 3 and [CoII(L)(pic)Cl]; 4, (where L = N,N-bis(pyridin-2-ylmethyl)aniline, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, pic = picolinic acid) were systematically synthesized and characterized by different analytical and spectroscopic methods. All the complexes were structurally identified by single-crystal X-ray diffraction analysis. Penta-coordinated complex 1 adopted a distorted trigonal bipyramidal geometry, whereas hexacoordinated complexes 2-4 have distorted octahedral geometry. The interactions of salmon sperm DNA (ss-DNA) with our synthesized complexes 1-4 were investigated by absorbance and fluorescence spectroscopy. All the complexes are very susceptible to DNA binding and exhibited binding affinities (Kb) in the order of ∼104 M-1, indicating their strong interaction with ss-DNA. The Stern-Volmer constant (Ksv) ranged from 0.46 ± 0.01 × 104 to 1.08 ± 0.04 × 104 M-1, suggesting weak or moderate binding with DNA. Agarose gel electrophoresis revealed the DNA cleavage activity in vitro for 2-4, which could efficiently cleave the supercoiled plasmid DNA without any external agents; however, with the addition of H2O2, the cleavage property was enhanced. Live-cell imaging and other biochemical assays demonstrated the ability of Co(II) complexes 1-4 to induce significant cytotoxicity in A549 lung cancer cells with IC50 values of 32.14 ± 1.3 µM, 3.14 ± 0.16 µM, 15.78 ± 0.72 µM and 18.45 ± 0.92 µM, and in MDA-MB-231 breast cancer cells with IC50 values of 20.42 ± 0.92 µM, 0.41 ± 0.02 µM, 2.31 ± 0.12 µM and 9.67 ± 0.35 µM, respectively.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Antineoplastic Agents/chemistry , Coordination Complexes/chemistry , Copper/chemistry , Crystallography, X-Ray , DNA/chemistry , DNA Cleavage , Hydrogen Peroxide , Molecular Structure
14.
Arterioscler Thromb Vasc Biol ; 42(3): e74-e84, 2022 03.
Article in English | MEDLINE | ID: mdl-35109671

ABSTRACT

Clonal expansion is a process that can drive pathogenesis in human diseases, with atherosclerosis being a prominent example. Despite advances in understanding the etiology of atherosclerosis, clonality studies of vascular cells remain in an early stage. Recently, several paradigm-shifting preclinical studies have identified clonal expansion of progenitor cells in the vasculature in response to atherosclerosis. This review provides an overview of cell clonality in atherosclerotic progression, focusing particularly on smooth muscle cells and macrophages. We discuss key findings from the latest research that give insight into the mechanisms by which clonal expansion of vascular cells contributes to disease pathology. The further probing of these mechanisms will provide innovative directions for future progress in the understanding and therapy of atherosclerosis and its associated cardiovascular diseases.


Subject(s)
Atherosclerosis/pathology , Myocytes, Smooth Muscle/pathology , Animals , Atherosclerosis/etiology , Cell Lineage , Cell Proliferation , Clone Cells/pathology , Disease Models, Animal , Humans , Macrophages/pathology , Mice , Mice, Transgenic , Plaque, Atherosclerotic/etiology , Plaque, Atherosclerotic/pathology , Stem Cells/pathology
15.
J Clin Invest ; 132(5)2022 03 01.
Article in English | MEDLINE | ID: mdl-34990407

ABSTRACT

Obstructive arterial diseases, including supravalvular aortic stenosis (SVAS), atherosclerosis, and restenosis, share 2 important features: an abnormal or disrupted elastic lamellae structure and excessive smooth muscle cells (SMCs). However, the relationship between these pathological features is poorly delineated. SVAS is caused by heterozygous loss-of-function, hypomorphic, or deletion mutations in the elastin gene (ELN), and SVAS patients and elastin-mutant mice display increased arterial wall cellularity and luminal obstructions. Pharmacological treatments for SVAS are lacking, as the underlying pathobiology is inadequately defined. Herein, using human aortic vascular cells, mouse models, and aortic samples and SMCs derived from induced pluripotent stem cells of ELN-deficient patients, we demonstrated that elastin insufficiency induced epigenetic changes, upregulating the NOTCH pathway in SMCs. Specifically, reduced elastin increased levels of γ-secretase, activated NOTCH3 intracellular domain, and downstream genes. Notch3 deletion or pharmacological inhibition of γ-secretase attenuated aortic hypermuscularization and stenosis in Eln-/- mutants. Eln-/- mice expressed higher levels of NOTCH ligand JAGGED1 (JAG1) in aortic SMCs and endothelial cells (ECs). Finally, Jag1 deletion in SMCs, but not ECs, mitigated the hypermuscular and stenotic phenotype in the aorta of Eln-/- mice. Our findings reveal that NOTCH3 pathway upregulation induced pathological aortic SMC accumulation during elastin insufficiency and provide potential therapeutic targets for SVAS.


Subject(s)
Aortic Stenosis, Supravalvular , Elastin , Jagged-1 Protein/metabolism , Amyloid Precursor Protein Secretases , Animals , Aorta/metabolism , Aortic Stenosis, Supravalvular/genetics , Aortic Stenosis, Supravalvular/metabolism , Aortic Stenosis, Supravalvular/pathology , Constriction, Pathologic , Elastin/genetics , Elastin/metabolism , Endothelial Cells/metabolism , Humans , Mice , Receptor, Notch3/genetics
16.
Free Radic Biol Med ; 177: 189-200, 2021 12.
Article in English | MEDLINE | ID: mdl-34666149

ABSTRACT

As hypoxia is a major driver for the pathophysiology of COVID-19, it is crucial to characterize the hypoxic response at the cellular and molecular levels. In order to augment drug repurposing with the identification of appropriate molecular targets, investigations on therapeutics preventing hypoxic cell damage is required. In this work, we propose a hypoxia model based on alveolar lung epithelial cells line using chemical inducer, CoCl2 that can be used for testing calcium channel blockers (CCBs). Since recent studies suggested that CCBs may reduce the infectivity of SARS-Cov-2, we specifically select FDA approved calcium channel blocker, nifedipine for the study. First, we examined hypoxia-induced cell morphology and found a significant increase in cytosolic calcium levels, mitochondrial calcium overload as well as ROS production in hypoxic A549 cells. Secondly, we demonstrate the protective behaviour of nifedipine for cells that are already subjected to hypoxia through measurement of cell viability as well as 4D imaging of cellular morphology and nuclear condensation. Thirdly, we show that the protective effect of nifedipine is achieved through the reduction of cytosolic calcium, mitochondrial calcium, and ROS generation. Overall, we outline a framework for quantitative analysis of mitochondrial calcium and ROS using 3D imaging in laser scanning confocal microscopy and the open-source image analysis platform ImageJ. The proposed pipeline was used to visualize mitochondrial calcium and ROS level in individual cells that provide an understanding of molecular targets. Our findings suggest that the therapeutic value of nifedipine may potentially be evaluated in the context of COVID-19 therapeutic trials.


Subject(s)
COVID-19 , Nifedipine , A549 Cells , Calcium , Calcium Channel Blockers/pharmacology , Calcium Channel Blockers/therapeutic use , Cell Death , Humans , Hypoxia/drug therapy , Nifedipine/pharmacology , SARS-CoV-2 , Superoxides
17.
Cells ; 10(3)2021 03 08.
Article in English | MEDLINE | ID: mdl-33800271

ABSTRACT

Mural cells collectively refer to the smooth muscle cells and pericytes of the vasculature. This heterogenous population of cells play a crucial role in the regulation of blood pressure, distribution, and the structural integrity of the vascular wall. As such, dysfunction of mural cells can lead to the pathogenesis and progression of a number of diseases pertaining to the vascular system. Cardiovascular diseases, particularly atherosclerosis, are perhaps the most well-described mural cell-centric case. For instance, atherosclerotic plaques are most often described as being composed of a proliferative smooth muscle cap accompanied by a necrotic core. More recently, the role of dysfunctional mural cells in neurodegenerative diseases, such as Alzheimer's and Parkinson's disease, is being recognized. In this review, we begin with an exploration of the mechanisms underlying atherosclerosis and neurodegenerative diseases, such as mural cell plasticity. Next, we highlight a selection of signaling pathways (PDGF, Notch and inflammatory signaling) that are conserved across both diseases. We propose that conserved mural cell signaling mechanisms can be exploited for the identification or development of dual-pronged therapeutics that impart both cardio- and neuroprotective qualities.


Subject(s)
Alzheimer Disease/drug therapy , Atherosclerosis/drug therapy , Myocytes, Smooth Muscle/drug effects , Parkinson Disease/drug therapy , Pericytes/drug effects , Plaque, Atherosclerotic/drug therapy , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Animals , Atherosclerosis/genetics , Atherosclerosis/metabolism , Atherosclerosis/pathology , Cardiotonic Agents/pharmacology , Disease Models, Animal , Gene Expression Regulation , Humans , Mice , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Neuroprotective Agents/pharmacology , Parkinson Disease/genetics , Parkinson Disease/metabolism , Parkinson Disease/pathology , Pericytes/metabolism , Pericytes/pathology , Plaque, Atherosclerotic/genetics , Plaque, Atherosclerotic/metabolism , Plaque, Atherosclerotic/pathology , Platelet-Derived Growth Factor/genetics , Platelet-Derived Growth Factor/metabolism , Receptors, Notch/genetics , Receptors, Notch/metabolism , Signal Transduction
18.
Nat Metab ; 3(2): 128-130, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33619383
19.
Heart Lung Circ ; 30(6): 795-806, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33461916

ABSTRACT

Colchicine, an inexpensive immunomodulatory drug used traditionally to treat gout and familial Mediterranean fever, is rapidly accumulating basic and clinical evidence for a therapeutic role in atherosclerotic cardiovascular disease. Its athero-protective properties are thought to be mainly related to its effect on tubulin polymerisation, enabling a broad range of effect on multiple atherosclerotic plaque cell types and cellular processes, including cell division, cell migration as well as pro-inflammatory cytokine and chemokine secretion. These properties indicate the potential to favourably affect all stages of atherosclerotic plaque development including formation, progression, destabilisation, and plaque rupture. This review focusses on the pharmacology of colchicine, the mechanisms by which it modulates atherosclerosis pathobiology, and summarises the current clinical evidence for its use along with the upcoming clinical trial landscape. Given the current lack of primary immunomodulatory drugs in the treatment of atherosclerosis, colchicine is a promising candidate to fill this therapeutic gap.


Subject(s)
Atherosclerosis , Cardiovascular Diseases , Coronary Artery Disease , Plaque, Atherosclerotic , Anti-Inflammatory Agents/therapeutic use , Atherosclerosis/drug therapy , Colchicine/therapeutic use , Coronary Artery Disease/drug therapy , Humans , Plaque, Atherosclerotic/drug therapy
20.
Blood ; 137(14): 1970-1979, 2021 04 08.
Article in English | MEDLINE | ID: mdl-33512442

ABSTRACT

We determined the efficacy of tocilizumab (TCZ) in preventing grade 2-4 acute graft-versus-host disease (aGVHD) in patients with acute leukemia or myelodysplasia undergoing matched sibling donor (MSD) or volunteer unrelated donor (VUD) allogeneic stem cell transplantation after myeloablative or reduced-intensity conditioning across 5 Australian centers. A total of 145 patients (50 MSD, 95 VUD) were randomly assigned to placebo or TCZ on day -1. All patients received T-cell-replete peripheral blood stem cell grafts and graft-versus-host disease (GVHD) prophylaxis with cyclosporin/methotrexate. A planned substudy analyzed the VUD cohort. With a median follow-up of 746 days, the incidence of grade 2-4 aGVHD at day 100 for the entire cohort was 36% for placebo vs 27% for TCZ (hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.38-1.26; P = .23) and 45% vs 32% (HR, 0.61; 95% CI, 0.31-1.22; P = .16) for the VUD subgroup. The incidence of grade 2-4 aGVHD at day 180 for the entire cohort was 40% for placebo vs 29% for TCZ (HR, 0.68; 95% CI, 0.38-1.22; P = .19) and 48% vs 32% (HR, 0.59; 95% CI, 0.30-1.16; P = .13) for the VUD subgroup. Reductions in aGVHD were predominantly in grade 2 disease. For the entire cohort, transplant-related mortality occurred in 8% vs 11% of placebo-treated vs TCZ-treated patients, respectively (P = .56), and overall survival was 79% vs 71% (P = .27). Median day to neutrophil and platelet engraftment was delayed by 2 to 3 days in TCZ-treated patients, whereas liver toxicity and infectious complications were similar between groups. In this phase 3 randomized double-blind trial, TCZ showed nonsignificant trends toward reduced incidence of grade 2-4 aGVHD in recipients from HLA-matched VUDs but no improvements in long term-survival.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Cyclosporine/therapeutic use , Graft vs Host Disease/prevention & control , Hematopoietic Stem Cell Transplantation , Immunosuppressive Agents/therapeutic use , Methotrexate/therapeutic use , Adult , Double-Blind Method , Female , Humans , Leukemia/therapy , Male , Middle Aged , Myelodysplastic Syndromes/therapy , Placebo Effect , Transplantation, Homologous , Treatment Outcome
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