Vessel Remodeling Research Articles

PULMONARY ARTERIAL HYPERTENSION ASSOCIATED WITH CONGENITAL HEART DISEASE: RATIONALE FOR MANAGEMENT ALGORITHM BASED ON A LITERATURE REVIEW

The substantial progress achieved in cardiology and paediatric cardiac surgery has led to a considerable increase of life expectancy of patients with congenital heart disease (CHD), and at the same time to growing number of adult patients developing pulmonary arterial hypertension (PAH) associated with congenital heart defects. Nowadays guidelines were developed and updated for PAH, but no expert recommendations exist for effective management of PAH associated with CHD. Thus, it is important to develop an algorithm for managing these patients, based on international standards and a comprehensive understanding of prognostic markers of worsening the course of pulmonary arterial hypertension (PAH), considering local cardiac tertiary hospitals' capabilities.
 The aim. To highlight the pathophysiology and clinical characteristics of PAH-CHD patients, identify prognostic markers for its onset and progression, and develop a management algorithm for patients.
 Results. The article presents the pathophysiology of PAH-CHD, the mechanisms of right ventricle adaptation to pressure overload, which determine the functional abilities of patients and prognosis, PAH formation, and progression after defects correction. The accurate identification of stages in PAH-CHD (volume overload, mixed, stage of pulmonary vascular disease) is essential for the timely determination of surgical intervention, selecting conservative treatment strategies, and predicting the outcomes of surgical defect correction. The type of defect, its size, and the volume of blood flow through the defect influence the onset and progression of PH-CHD. We review the pathophysiology and clinical features of PAH-CHD, as well as the reasons for the late diagnosis of heart failure at the stage of severe decompensation and irreversible remodelling of the lung vessels when diuretic therapy is not effective enough and inotropic support, circulatory mechanical support and heart / lung complex transplantation are required. The necessity of developing new scales for stratifying the risk of PAH-CHD is justified considering the particularities of the disease course and cardiac hemodynamic in different anatomical types of the defects. Based on this literature review, at the Municipal Enterprise «Dnipropetrovsk Regional Clinical Center for Diagnostics and Treatment» of the Dnipropetrovsk Regional Council» the algorithm for managing patients with PAH-CHD was devised and implemented into clinical practice.
 Conclusions. PAH is a common complication of CHD. The prevalence of PAH-CHD is substantial and it can manifest and progress even in patients with previously corrected heart defects. To effectively manage patients with PAH-CHD, an algorithm has been devised and implemented in clinical practice. It includes factors that have demonstrated associations with poor prognosis which are more than two hospitalizations for HF in the last year, pulmonary vascular resistance (PVR) (or index of PVR), mean pressure in the pulmonary artery, pulmonary capillary wedge pressure, left ventricular ejection fraction, heart failure with a reduced ejection fraction, right ventricle heart failure, NYHA FC, high risk of atrial fibrillation or flutter, 6-minute walking test distance, NTproBNP, highly sensitive C-reactive protein, B-lines on lung ultrasound, glomerular filtration rate, haemoglobin, platelet count, sodium, Model for End-Stage Liver Disease scale.

Fabric-Enhanced Vascular Graft with Hierarchical Structure for Promoting the Regeneration of Vascular Tissue.

Natural blood vessels have completed functions, including elasticity, compliance, and excellent antithrombotic properties because of their mature structure. To replace damaged blood vessels, vascular grafts should perform these functions by simulating the natural vascular structures. Although the structures of natural blood vessels are thoroughly explored, constructing a small-diameter vascular graft that matches the mechanical and biological properties of natural blood vessels remains a challenge. A hierarchical vascular graft is fabricated by Electrospinning, Braiding, and Thermally induced phase separation (EBT) processes, which could simulate the structure of natural blood vessels. The internal electrospun structure facilitates the adhesion of endothelial cells, thereby accelerating endothelialization. The intermediate PLGA fabric exhibits excellent mechanical properties, which allow it to maintain its shape during long-term transplantation and prevent graft expansion. The external macroporous structure is beneficial for cell growth and infiltration. Blood vessel remodeling aims to combine a structure that promotes tissue regeneration with anti-inflammatory materials. The results in vitro demonstrated that it EBT vascular graft (EBTVG) has matched the mechanical properties, reliable cytocompatibility, and the strongest endothelialization in situ. The results in vitro and replacement of the resected artery in vivo suggest that the EBTVG combines different structural advantages with biomechanical properties and reliable biocompatibility, significantly promoting the stabilization and regeneration of vascular endothelial cells and vascular smooth muscle cells, as well as stabilizing the blood microenvironment.

Mechanobiological tortuosity of blood vessels with stress-modulated growth and remodeling

The stability of blood vessels is essential for maintaining their functions, while severe blood vessel tortuosity leads to various clinical complications. The growth and remodeling of blood vessels, which are regulated by mechanical and biochemical cues, cause residual stresses that affect vessel stability. In this paper, we combine theory and simulations to study the mechanobiological behavior of blood vessels with stress-modulated growth and remodeling. Effects of the volumetric growth of the matrix and the turnover and reorientation of collagen fibers are accounted for. Linear stability analysis is first carried out to investigate the mechanobiological stability of blood vessels. By developing a finite element method that incorporates stress-modulated growth and remodeling, we validate the theoretical solution of the critical state and further capture the postbuckling evolution of blood vessels. Our results show that an increased internal pressure can lead to the thickening of the vessel wall, which stabilizes the blood vessels mechanically, whereas the effect of internal pressure on the mechanobiological buckling is nonmonotonic. Compared to the mechanical instability, the mechanobiological buckling results in a larger mode number and a shorter wavelength, as usually observed in varicose veins. Vessels during postbuckling may exhibit non-uniform wall thicknesses, in consistency with the experimental observation on tortuous aortas. These findings highlight the crucial role of mechanical remodeling in tissue morphogenesis and could deepen the understanding of mechanobiological mechanisms underlying the formation and development of blood vessel tortuosity.

Post-angioplasty remodeling of coronary arteries investigated via a chemo-mechano-biological in silico model

This work presents the application of a chemo-mechano-biological constitutive model of soft tissues for describing tissue inflammatory response to damage in collagen constituents. The material model is implemented into a nonlinear finite element formulation to follow up a coronary standard balloon angioplasty for one year. Numerical results, compared with available in vivo clinical data, show that the model reproduces the temporal dynamics of vessel remodeling associated with subintimal damage. Such dynamics are bimodular, being characterized by an early tissue resorption and lumen enlargement, followed by late tissue growth and vessel constriction. Applicability of the modeling framework in retrospective studies is demonstrated, and future extension towards prospective applications is discussed.

Tumor-immune metaphenotypes orchestrate an evolutionary bottleneck that promotes metabolic transformation.

Metabolism plays a complex role in the evolution of cancerous tumors, including inducing a multifaceted effect on the immune system to aid immune escape. Immune escape is, by definition, a collective phenomenon by requiring the presence of two cell types interacting in close proximity: tumor and immune. The microenvironmental context of these interactions is influenced by the dynamic process of blood vessel growth and remodelling, creating heterogeneous patches of well-vascularized tumor or acidic niches. Here, we present a multiscale mathematical model that captures the phenotypic, vascular, microenvironmental, and spatial heterogeneity which shapes acid-mediated invasion and immune escape over a biologically-realistic time scale. The model explores several immune escape mechanisms such as i) acid inactivation of immune cells, ii) competition for glucose, and iii) inhibitory immune checkpoint receptor expression (PD-L1). We also explore the efficacy of anti-PD-L1 and sodium bicarbonate buffer agents for treatment. To aid in understanding immune escape as a collective cellular phenomenon, we define immune escape in the context of six collective phenotypes (termed "meta-phenotypes"): Self-Acidify, Mooch Acid, PD-L1 Attack, Mooch PD-L1, Proliferate Fast, and Starve Glucose. Fomenting a stronger immune response leads to initial benefits (additional cytotoxicity), but this advantage is offset by increased cell turnover that leads to accelerated evolution and the emergence of aggressive phenotypes. This creates a bimodal therapy landscape: either the immune system should be maximized for complete cure, or kept in check to avoid rapid evolution of invasive cells. These constraints are dependent on heterogeneity in vascular context, microenvironmental acidification, and the strength of immune response. This model helps to untangle the key constraints on evolutionary costs and benefits of three key phenotypic axes on tumor invasion and treatment: acid-resistance, glycolysis, and PD-L1 expression. The benefits of concomitant anti-PD-L1 and buffer treatments is a promising treatment strategy to limit the adverse effects of immune escape.

Apela promotes blood vessel regeneration and remodeling in zebrafish

In contrast to adult mammals, zebrafish display a high capacity to heal injuries and repair damage to various organs. One of the earliest responses to injury in adult zebrafish is revascularization, followed by tissue morphogenesis. Tissue vascularization entails the formation of a blood vessel plexus that remodels into arteries and veins. The mechanisms that coordinate these processes during vessel regeneration are poorly understood. Hence, investigating and identifying the factors that promote revascularization and vessel remodeling have great therapeutic potential. Here, we revealed that fin vessel remodeling critically depends on Apela peptide. We found that Apela selectively accumulated in newly formed zebrafish fin tissue and vessels. The temporal expression of Apela, Apln, and their receptor Aplnr is different during the regenerative process. While morpholino-mediated knockdown of Apela (Mo-Apela) prevented vessel remodeling, exogenous Apela peptide mediated plexus repression and the development of arteries in regenerated fins. In contrast, Apela enhanced subintestinal venous plexus formation (SIVP). The use of sunitinib completely inhibited vascular plexus formation in zebrafish, which was not prevented by exogenous application. Furthermore, Apela regulates the expression of vessel remolding-related genes including VWF, IGFPB3, ESM1, VEGFR2, Apln, and Aplnr, thereby linking Apela to the vascular plexus factor network as generated by the STRING online database. Together, our findings reveal a new role for Apela in vessel regeneration and remodeling in fin zebrafish and provide a framework for further understanding the cellular and molecular mechanisms involved in vessel regeneration.

Factor Analysis for Predicting the Structural Reorganization of the Microvasculature of the Kidneys in Patients with Glomerulonephritis and Arterial Hypertension

Objectives. Evaluation of the relationship of clinical, laboratory and morphological factors with remodeling of small-diameter renal arteries in patients with glomerulonephritis (GN) and arterial hypertension (AH). Materials and methods. The study included 105 patients (average age 37.1±1.2 years) with primary GN and hypertension who had indications for morphological investigation of kidney tissue. All patients underwent a standard examination for kidney disease, a morphological study of kidney tissue with a description of the changes that occur in the presence of glomerulonephritis, corresponding to the individual severity of the pathological process. The presence of signs of a tubulointerstitial component of damage (or tubulointerstitial component — TIC) in the form of tubulointerstitial infl ammation (TIV), fi brosis (TIF) was assessed. Vasometry of the interlobular artery (IA) was performed. The value of the intima-media complex (IMC) was considered to be a sign of IA remodeling. A sign of MA remodeling was considered to be an intima-media complex (IMC) value of more than 30.43 μm. Results. Among clinical and laboratory risk factors, an increase in systolic blood pressure has a statistically signifi cant effect on the likelihood of increasing IMC (χ2-criterion = 5.76, p = 0.016), arterial hypertension stage (χ2-criterion = 9.45, p = 0.002), blood urea level (χ2-criterion = 8.11, p = 0.004), decrease in glomerular fi ltration rate (χ2-criterion = 5.0, p = 0.025), increase in the stage of chronic kidney disease (χ2-criterion = 10.32, p = 0.001). The presence of signs of GN progression, such as an increase in erythrocyte sedimentation rate (ESR) or proteinuria, did not have a statistically significant effect on the risk of IA remodeling (p>0.05). The increase in IA IMC is affected by the presence of hyalinosis of glomerular capillary loops (χ2-criterion = 7.56, p = 0.006), periglomerular hyalinosis (χ2-criterion = 6.96, p = 0.008), sclerosis of the glomerulus (χ2-criterion = 3.9, p = 0.048), increased fibrosis of tubulointerstitium (χ2-criterion = 12.16, p = 0.0005). Conclusion. In GN and AH, remodeling of small-diameter renal vessels occurs due to the influence of AH and its severity, tubulointerstitial changes in the renal tissue. New risk factors for vascular remodeling have been obtained — changes in the glomerulus. At the same time, the inflammatory and autoimmune mechanisms of GN were not associated with changes in the vascular wall. The role of hypertension is decisive in changing the structure of small-diameter kidneys.

Trafficking dynamics of VEGFR1, VEGFR2, and NRP1 in human endothelial cells.

The vascular endothelial growth factor (VEGF) family of cytokines are key drivers of blood vessel growth and remodeling. These ligands act via multiple VEGF receptors (VEGFR) and co-receptors such as Neuropilin (NRP) expressed on endothelial cells. These membrane-associated receptors are not solely expressed on the cell surface, they move between the surface and intracellular locations, where they can function differently. The location of the receptor alters its ability to 'see' (access and bind to) its ligands, which regulates receptor activation; location also alters receptor exposure to subcellularly localized phosphatases, which regulates its deactivation. Thus, receptors in different subcellular locations initiate different signaling, both in terms of quantity and quality. Similarly, the local levels of co-expression of other receptors alters competition for ligands. Subcellular localization is controlled by intracellular trafficking processes, which thus control VEGFR activity; therefore, to understand VEGFR activity, we must understand receptor trafficking. Here, for the first time, we simultaneously quantify the trafficking of VEGFR1, VEGFR2, and NRP1 on the same cells-specifically human umbilical vein endothelial cells (HUVECs). We build a computational model describing the expression, interaction, and trafficking of these receptors, and use it to simulate cell culture experiments. We use new quantitative experimental data to parameterize the model, which then provides mechanistic insight into the trafficking and localization of this receptor network. We show that VEGFR2 and NRP1 trafficking is not the same on HUVECs as on non-human ECs; and we show that VEGFR1 trafficking is not the same as VEGFR2 trafficking, but rather is faster in both internalization and recycling. As a consequence, the VEGF receptors are not evenly distributed between the cell surface and intracellular locations, with a very low percentage of VEGFR1 being on the cell surface, and high levels of NRP1 on the cell surface. Our findings have implications both for the sensing of extracellular ligands and for the composition of signaling complexes at the cell surface versus inside the cell.

Monitoring of the right ventricular responses to pressure overload: prognostic value and usefulness of echocardiography for clinical decision-making.

Regardless of whether pulmonary hypertension (PH) results from increased pulmonary venous pressure in left-sided heart diseases or from vascular remodeling and/or obstructions in pre-capillary pulmonary vessels, overload-induced right ventricular (RV) dysfunction and its final transition into right-sided heart failure is a major cause of death in PH patients. Being particularly suited for non-invasive monitoring of the right-sided heart, echocardiography has become a useful tool for optimizing the therapeutic decision-making and evaluation of therapy results in PH. The review provides an updated overview on the pathophysiological insights of heart-lung interactions in PH of different etiology, as well as on the diagnostic and prognostic value of echocardiography for monitoring RV responses to pressure overload. The article focuses particularly on the usefulness of echocardiography for predicting life-threatening aggravation of RV dysfunction in transplant candidates with precapillary PH, as well as for preoperative prediction of post-operative RV failure in patients with primary end-stage left ventricular (LV) failure necessitating heart transplantation or a LV assist device implantation. In transplant candidates with refractory pulmonary arterial hypertension, a timely prediction of impending RV decompensation can contribute to reduce both the mortality risk on the transplant list and the early post-transplant complications caused by severe RV dysfunction, and also to avoid combined heart-lung transplantation. The review also focuses on the usefulness of echocardiography for monitoring the right-sided heart in patients with acute respiratory distress syndrome, particularly in those with refractory respiratory failure requiring extracorporeal membrane oxygenation support. Given the pathophysiologic particularity of severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection to be associated with a high incidence of thrombotic microangiopathy-induced increase in the pulmonary resistance, echocardiography can improve the selection of temporary mechanical cardio-respiratory support strategies and can therefore contribute to the reduction of mortality rates. On the whole, the review aims to provide a theoretical and practical basis for those who are or intend in the future to be engaged in this highly demanding field.

A Systematic Comparison of Normal Structure and Function of the Greater Thoracic Vessels.

The greater thoracic vessels are central to a well-functioning circulatory system and are often targeted in congenital heart surgeries, yet the structure and function of these vessels have not been well studied. Here we use consistent methods to quantify and compare microstructural features and biaxial biomechanical properties of the following six greater thoracic vessels in wild-type mice: ascending thoracic aorta, descending thoracic aorta, right subclavian artery, right pulmonary artery, thoracic inferior vena cava, and superior vena cava. Specifically, we determine volume fractions and orientations of the structurally significant wall constituents (i.e., collagen, elastin, and cell nuclei) using multiphoton imaging, and we quantify vasoactive responses and mechanobiologically relevant mechanical quantities (e.g., stress, stiffness) using computer-controlled biaxial mechanical testing. Similarities and differences across systemic, pulmonary, and venous circulations highlight underlying design principles of the vascular system. Results from this study represent another step towards understanding growth and remodeling of greater thoracic vessels in health, disease, and surgical interventions by providing baseline information essential for developing and validating predictive computational models.

Changes in the indicators of stiffness and remodeling of magistral arteries in young patients at the early stage of essential hypertension under conditions of syntropy with obesity.

Aim: The study and analysis of indicators of remodeling and rigidity of magistral vessels in young essential hypertension patients with abdominal obesity and determination of the detected changes as a possible criterion for their remodeling.. Materials and Methods: 98 young people with essential hypertension and obesity were included in the study. The structure of the carotid artery and its stiffness were assessed using the ultrasound method, and the level of abdominal fat was determined using dual-energy X-ray absorptiometry. Results: Carotid Intima-Media Thickness in patients with essential hypertension reliably exceeded the corresponding indicator of the control group. We observed a significant increase in arterial stiffness indicators, which is explained by the increased stiffness of blood vessels in patients with obesity. During the correlation analysis, it was established that the relationship between the level of abdominal fat and the elasticity of the vascular wall was positive and strong, which indicated the dominant role of the abdominal type of obesity in the remodeling of the vascular wall in young patients with essential hypertension in combination with obesity. Conclusions: In young patients at the early stage of the formation of essential hypertension, there are signs of a decrease in resilient-elastic properties and remodeling of magistral vessels, whose severity is significantly stronger in combination with abdominal obesity.

«Selfish brain» theory: modern concept and practical use. (Literature review)

In the early 20th century, the term «selfish brain» appeared in scientific literature, around which theory was formed, finding its proof in the work of doctors and scientists. The basic principle of the theory is that the superior hierarchy of the brain, whose needs are prioritized, results in the primary satisfaction of one's own needs, often to the detriment of the functioning of other organs and systems. The origins of the theory of «selfish brain», according to researchers, lie in the work of neurosurgery pioneer Harvey Cushing, who discovered a reflex named after him and consisting in increasing arterial pressure at high intracranial pressure. Later, the field of action of this phenomenon was expanded by specialists who showed that an increase in arterial pressure can occur not only in critical situations and arise not only at high intracranial pressure, but also as a result of hypoxia of the brain. It was also found that the remodeling of intracranial vessels in hypertensive disease may be not only a consequence, but also a cause. Currently, similar patterns have been established in relation to other processes - exchange, immune and others. It was found that the priority of brain energy needs in different situations can affect insulin resistance and glucose tolerance. These effects can be realized through various mechanisms, but the advantage is through vegetative (autonomous) nervous system, mainly through sympathetic link, and also through simulation of the functioning of parasympathetic link. It is known that there is currently a rapidly increasing number of pathologies associated with degenerative-dystrophic processes of the spine, and other factors that disrupt the blood flow in the vertex-basilar zone of the Willis circle, Correction of these processes with the help of a set of manual techniques and physical methods (A. Yu. Shishonin's method with correction of aerobic-anaerobic energy balance in the reflex zones of the brain stem) Can have a good effect on the treatment of hypertensive disease and other chronic non-communicable diseases.

Função do Ventrículo Direito e Estresse Oxidativo Melhoram com a Administração de Hormônios da Tireoide e Suco de Uva em um Modelo de Hipertensão Pulmonar

Abstract Background Adverse remodeling of lung vessels elevates pulmonary pressure and provokes pulmonary arterial hypertension (PAH). PAH results in increased right ventricle (RV) afterload, causing ventricular hypertrophy and the onset of heart failure. There is no specific treatment for maladaptive RV remodeling secondary to PAH. Objectives This study aims to explore two therapeutic approaches, grape juice (GJ) and thyroid hormones (TH), on PAH-induced oxidative stress and cardiac functional changes. Methods Parameters of echocardiography related to lung vessel resistance (AT/ET ratio), RV contractility (TAPSE), and RV diastolic function (E/A peaks ratio) were evaluated. Also, total ROS, lipid peroxidation, antioxidant enzymes, calcium handling proteins, pro-oxidant and antioxidant protein expression were measured. Values of p<0.05 were considered statistically significant. Results Both GJ and TH treatments demonstrated reductions in pulmonary resistance (~22%) and improvements in TAPSE (inotropism ~11%) and AT/ET ratio (~26%) (p<0.05). There were no changes amongst groups regarding the E/A peak ratio. Although ROS and TBARS were not statistically significant, GJ and TH treatments decreased xanthine oxidase (~49%) levels and normalized HSP70 and calcium handling protein expression (p<0.05). However, only TH treatment ameliorated diastolic function (~50%) and augmented NRF2 immunocontent (~48%) (p<0.05). Conclusions To the best of our knowledge, this study stands as a pioneer in showing that TH administered together with GJ promoted functional and biochemical improvements in a PAH model. Moreover, our data suggest that GJ and TH treatments were cardioprotective, combined or not, and exhibited their beneficial effects by modulating oxidative stress and calcium-handling proteins.

In Vitro Experimental Approach for Studying Human Pulmonary Artery Smooth Muscle Cells and Endothelial Cells Proliferation and Migration.

Pulmonary arterial hypertension (PAH) is a severe vascular disease characterized by persistent precapillary pulmonary hypertension, leading to right heart failure and death. Despite intense research in the last decades, PAH remains an incurable disease with high morbidity and mortality. New directions and therapies to improve understanding and treatment of PAH are desperately needed. The pathological mechanisms leading to this fatal disorder remain mostly undetermined, although structural remodeling of the pulmonary vessels is known to be an early feature of PAH. Pulmonary vascular remodeling includes proliferation and migration of pulmonary artery smooth muscle cells (PASMCs) and pulmonary artery endothelial cells (PAECs). The use of in vitro approaches is useful to delineate the mechanisms involved in the pathogenesis of PAH and to identify new therapeutic strategies for PAH. In this chapter, we describe protocols for culturing and assessing proliferation and migration of human PASMCs and PAECs.

Tyrosine kinases: multifaceted receptors at the intersection of several neurodegenerative disease-associated processes.

Tyrosine kinases (TKs) are catalytic enzymes activated by auto-phosphorylation that function by phosphorylating tyrosine residues on downstream substrates. Tyrosine kinase inhibitors (TKIs) have been heavily exploited as cancer therapeutics, primarily due to their role in autophagy, blood vessel remodeling and inflammation. This suggests tyrosine kinase inhibition as an appealing therapeutic target for exploiting convergent mechanisms across several neurodegenerative disease (NDD) pathologies. The overlapping mechanisms of action between neurodegeneration and cancer suggest that TKIs may play a pivotal role in attenuating neurodegenerative processes, including degradation of misfolded or toxic proteins, reduction of inflammation and prevention of fibrotic events of blood vessels in the brain. In this review, we will discuss the distinct roles that select TKs have been shown to play in various disease-associated processes, as well as identify TKs that have been explored as targets for therapeutic intervention and associated pharmacological agents being investigated as treatments for NDDs.

Quantitative Assessment Characteristics of Small Pulmonary Vessel Remodelling in Populations at High Risk for COPD and Smokers Using Low-Dose CT.

To explore the morphological alterations in small pulmonary vessels in populations at high risk for chronic obstructive pulmonary disease (COPD) and smokers based on multiple computed tomography (CT) quantitative parameters. A total of 1969 Three Major Chest Diseases Screening Study participants with available demographic data and smoking history who underwent low-dose chest CT from 2018 to 2020 were included. All subjects were divided into normal, high risk for COPD, and COPD groups according to their pulmonary function test (PFT) results. Furthermore, the three groups were further subdivided into never-smokers, current smokers, and former smokers subgroups according to their smoking history. Quantitative parameters, such as the number, area at 6 mm~24 mm subpleura and volume of small pulmonary vessels, were extracted by computer software. Differences in small pulmonary vessel parameters among the groups were compared using two-way ANOVA. The number, area at 6 mm~24 mm subpleura and volume of small pulmonary vessels in the group at high risk for COPD were lower than those in the normal group (P<0.05). The number, area at 6 mm~24 mm subpleura and volume of small pulmonary vessels in the COPD group were higher than those in the normal group (P<0.05). The number, area of small pulmonary vessels at 6 mm~12 mm subpleura in current smokers with high risk for COPD were higher than those in former smokers with high risk for COPD (P<0.05). The number, area, and volume of small pulmonary vessels in populations at high risk for COPD were decreased. Smoking cessation may impede structural changes in small pulmonary vessels in populations at high risk for COPD.

Unraveling the link: locomotor activity exerts a dual role in predicting Achilles tendon healing and boosting regeneration in mice.

Tendon disorders present significant challenges in the realm of musculoskeletal diseases, affecting locomotor activity and causing pain. Current treatments often fall short of achieving complete functional recovery of the tendon. It is crucial to explore, in preclinical research, the pathways governing the loss of tissue homeostasis and its regeneration. In this context, this study aimed to establish a correlation between the unbiased locomotor activity pattern of CRL:CD1 (ICR) mice exposed to uni- or bilateral Achilles tendon (AT) experimental injuries and the key histomorphometric parameters that influence tissue microarchitecture recovery. The study involved the phenotyping of spontaneous and voluntary locomotor activity patterns in male mice using digital ventilated cages (DVC®) with access to running wheels either granted or blocked. The mice underwent non-intrusive 24/7 long-term activity monitoring for the entire study period. This period included 7 days of pre-injury habituation followed by 28 days post-injury. The results revealed significant variations in activity levels based on the type of tendon injury and access to running wheels. Notably, mice with bilateral lesions and unrestricted wheel access exhibited significantly higher activity after surgery. Extracellular matrix (ECM) remodeling, including COL1 deposition and organization, blood vessel remodeling, and metaplasia, as well as cytological tendon parameters, such as cell alignment and angle deviation were enhanced in surgical (bilateral lesion) and husbandry (free access to wheels) groups. Interestingly, correlation matrix analysis uncovered a strong relationship between locomotion and microarchitecture recovery (cell alignment and angle deviation) during tendon healing. Overall, this study highlights the potential of using mice activity metrics obtained from a home-cage monitoring system to predict tendon microarchitecture recovery at both cellular and ECM levels. This provides a scalable experimental setup to address the challenging topic of tendon regeneration using innovative and animal welfare-compliant strategies.

Hyperactive mTORC1 in lung mesenchyme induces endothelial cell dysfunction and pulmonary vascular remodeling.

Lymphangioleiomyomatosis (LAM) is a progressive cystic lung disease caused by tuberous sclerosis complex 1/2 (TSC1/2) gene mutations in pulmonary mesenchymal cells, resulting in activation of the mechanistic target of rapamycin complex 1 (mTORC1). A subset of patients with LAM develop pulmonary vascular remodeling and pulmonary hypertension. Little, however, is known regarding how LAM cells communicate with endothelial cells (ECs) to trigger vascular remodeling. In end-stage LAM lung explants, we identified EC dysfunction characterized by increased EC proliferation and migration, defective angiogenesis, and dysmorphic endothelial tube network formation. To model LAM disease, we used an mTORC1 gain-of-function mouse model with a Tsc2 KO (Tsc2KO) specific to lung mesenchyme (Tbx4LME-Cre Tsc2fl/fl), similar to the mesenchyme-specific genetic alterations seen in human disease. As early as 8 weeks of age, ECs from mice exhibited marked transcriptomic changes despite an absence of morphological changes to the distal lung microvasculature. In contrast, 1-year-old Tbx4LME-Cre Tsc2fl/fl mice spontaneously developed pulmonary vascular remodeling with increased medial thickness. Single-cell RNA-Seq of 1-year-old mouse lung cells identified paracrine ligands originating from Tsc2KO mesenchyme, which can signal through receptors in arterial ECs. These ECs had transcriptionally altered genes including those in pathways associated with blood vessel remodeling. The proposed pathophysiologic mesenchymal ligand-EC receptor crosstalk highlights the importance of an altered mesenchymal cell/EC axis in LAM and other hyperactive mTORC1-driven diseases. Since ECs in patients with LAM and in Tbx4LME-Cre Tsc2fl/fl mice did not harbor TSC2 mutations, our study demonstrates that constitutively active mTORC1 lung mesenchymal cells orchestrated dysfunctional EC responses that contributed to pulmonary vascular remodeling.

Proteome Profiling of Brain Vessels in a Mouse Model of Cerebrovascular Pathology.

Cerebrovascular pathology that involves altered protein levels (or signaling) of the transforming growth factor beta (TGFβ) family has been associated with various forms of age-related dementias, including Alzheimer disease (AD) and vascular cognitive impairment and dementia (VCID). Transgenic mice overexpressing TGFβ1 in the brain (TGF mice) recapitulate VCID-associated cerebrovascular pathology and develop cognitive deficits in old age or when submitted to comorbid cardiovascular risk factors for dementia. We characterized the cerebrovascular proteome of TGF mice using mass spectrometry (MS)-based quantitative proteomics. Cerebral arteries were surgically removed from 6-month-old-TGF and wild-type mice, and proteins were extracted and analyzed by gel-free nanoLC-MS/MS. We identified 3602 proteins in brain vessels, with 20 demonstrating significantly altered levels in TGF mice. For total and/or differentially expressed proteins (p ≤ 0.01, ≥ 2-fold change), using multiple databases, we (a) performed protein characterization, (b) demonstrated the presence of their RNA transcripts in both mouse and human cerebrovascular cells, and (c) demonstrated that several of these proteins were present in human extracellular vesicles (EVs) circulating in blood. Finally, using human plasma, we demonstrated the presence of several of these proteins in plasma and plasma EVs. Dysregulated proteins point to perturbed brain vessel vasomotricity, remodeling, and inflammation. Given that blood-isolated EVs are novel, attractive, and a minimally invasive biomarker discovery platform for age-related dementias, several proteins identified in this study can potentially serve as VCID markers in humans.

Proteomics signatures of cerebrovascular pathology in TGFß1 overexpressing mice

AbstractBackgroundVascular cognitive impairment and dementia (VCID), the second most prevalent of the age‐related dementias, develops as a consequence of various types of cerebrovascular insults that damage brain function (Corriveau et al. 2016). Accumulating lines of evidence point to a link between VCID, both sporadic (Kim et al. 2006) and genetic (Hara et al. 2009, Zellner et al. 2018) forms, and the transforming growth factor beta (TGFB) family signaling. Transgenic mice overexpressing a constitutively active form of TGFβ1 in the brain (TGF mice) recap the cerebrovascular pathology seen in VCID (Wyss‐Coray et al. 2000, Tong et al. 2015), and develop VCID when submitted to a comorbid cardiovascular risk factor for dementia (Trigiani et al. 2020). Our aim was to characterize the cerebrovascular proteome of TGF mice using mass spectrometry‐based quantitative proteomics.MethodEighteen, 6‐month‐old‐TGF and ‐wildtype (WT) mice (N = 9/group) were transcardially perfused and pial arteries harvested under a dissecting microscope. Arterial proteins were extracted, trypsin‐digested, fractionated by strong cation exchange (SCX, gel‐free method) and analyzed by nanoLC‐MS/MS using nanoAcquity UPLC and ESI‐LTQ Orbitrap. For total and/or differentially‐expressed proteins (≥2‐fold change, p≤0.01) we i) performed characterization of proteins, and demonstrated presence of ii) protein RNA‐transcript in mouse and human brain vascular cells using transcriptomics datasets, and iii) identified proteins present in human‐extracellular‐vesicles (EVs) using Vesiclepedia.ResultWe identified 3602 proteins in brain vessels of WT and TGF mice, including canonical vascular proteins (e.g. Claudin‐5), and 103 direct (N = 103) and indirect (N = 1,942) interactors of TGFβ1 (Fig1). We also identified 83 proteins demonstrating significantly altered levels in TGF mice. Level dysregulation in these proteins point to perturbations in brain vessel vasomotricity, remodeling, and inflammation. We further demonstrated that several of the differentially‐expressed mouse proteins are i) expressed in the human brain vasculature, and ii) found as cargo proteins in EVs.ConclusionWe characterized the deleterious impact of TGFβ1 overproduction on the cerebrovascular proteome. Given the growing popularity of extracellular vesicles in blood as a novel and minimally invasive biomarker discovery platform for the age‐related dementias, including VCID, several of the proteins identified by us can serve as protein biomarkers in human.