Smooth Muscle Research Articles

Ultrasound findings of ovarian intravenous leiomyomatosis: a case report

Intravenous leiomyomatosis (IVL), an abnormal growth pattern of uterine leiomyomas, is a rare tumor characterized by masses of smooth muscle cells appearing histologically benign and proliferating within the blood vessels but not invading the tissue. Currently, there have been limited reports of early cases of IVL, and the imaging characteristics of IVL remain uncertain, resulting in frequent misdiagnosis prior to surgery. The present study utilized a case of early IVL detected through conventional ultrasound and subsequently confirmed via contrast-enhanced ultrasound (CEUS) to further investigate ultrasound’s diagnostic efficacy for early IVL detection. Here, a case of a 49-year-old woman was reported who presented with uterine leiomyoma and an echogenic mass in the left adnexal region on physical examination. Subsequent transvaginal CEUS examination revealed a left ovarian venous leiomyoma. The patient underwent resection of tumors in the uterus, bilateral ovaries, and left ovarian vein under general anesthesia. A venous plexus was identified above the left broad ligament close to the left ovary, and a myoma-like growth was detected in the posterior uterine wall during the operational procedure. Reports on pathology and immunohistochemistry verified leiomyomatosis with fatty metaplasia in the left broad ligament and uterine wall vein. The prognosis of patients with IVL is determined based on the appropriate surgical methods and the timely diagnosis of the condition. In this case, conventional ultrasound aided in the early identification of IVL, which was later verified by a CEUS examination, resulting in a successful surgical treatment. This example highlights the importance of ultrasound technology in diagnosing this uncommon condition and presents a new method for preoperative detection of IVL.

Long noncoding RNA Sngh20 promotes vascular smooth muscle cell senescence and abdominal aortic aneurysm growth by interacting with dead-box helicase 5

Abstract Background Development of non-surgical treatment of human abdominal aortic aneurysm (AAA) has clinical significance. Long noncoding RNAs (lncRNAs) are emerging as powerful mediators participated in cellular senescence process that a critical pathological alteration prompting AAA development. Purpose To investigate the role and underlying mechanism of lncRNA Small nucleolar RNA host gene-20 (Snhg20) in AAA formation. Methods Experimental AAA mice models were produced by peri-aortic CaPO4 injury in C57bl/6J mice or Subcutaneousangiotensin-II (Ang-II) infusion in Apoe–/– mice and gapmeR was used to knockdown Snhg20 expression. Adeno-associated virus and anti-IL-6 monoclonal antibody was used to knockdown dead-box helicase 5 (DDX5) and neutralize IL-6, respectively.Immunohistochemical and immunofluorescent staining, ELISA and real-time PCR were performed to determine the vascular structure and inflammation, cellular senescence and senescence-associated secretory phenotype (SASP) content in human and mouse AAA lesions. Human aortic SMC cell line was used to investigate the effect of Snhg20 knockdown on senescence and SASP in vitro. LncRNA pulldown and mass spectrometry were used to identify potential targets that interact with Snhg20. p53 DNA binding affinity was examined by EMSA. Results The expression of Snhg20 was downregulated in both human and mice AAA lesion. Snhg20 knockdown promoted SMC senescence and loss, vascular inflammation and AAA growth in both experimental AAA mice models. Mechanistically, Snhg20 interacted with DDX5, an important transcriptional coactivator of p53. The absence of snhg20 increased DDX5 and p53 interaction and thereby promoted p53 DNA binding affinity to transcriptionally initiate p21expression, resulting in increased cellular senescence and senescence-associated secretory phenotype (SASP) secretion, including IL-6. Moreover, DDX5 silencing or anti-IL-6 therapy rescued the SMC senescence and loss, vascular inflammation and AAA growth mediated by Snhg20 knockdown. Furthermore, human AAA lesions showed increased DDX5 co-localization with p53 and abundant senescent vascular SMC. Conclusion These findings identify an important role of Snhg20 in controlling vascular SMC senescence and SPAP expression and suggest that Snhg20 is a potential target for AAA treatment aimed at reducing VSMCs senescence.Schematic summary

RGS5 balances macrophage vs vascular smooth muscle cell origin of foam cells in apoE-deficient plaques

Abstract Background G Protein Coupled Receptors and regulators of G-protein signalling (RGS), play a pivotal role in the signalling processes associated with atherosclerosis [1]. RGS5 is highly expressed in aortic tissue [2]. Development of atherosclerotic plaque is a complex process that involves foam cells originating from macrophages (Mϕ) and/or vascular smooth muscle cells (VSMCs). Differentiation of Mϕ and VSMC into various intermediary cells of varying inflammatory potency affects atherosclerotic plaque composition and vulnerability [3]. We hypothesize that RGS5 is involved in signalling of foam cell transition and thus, plaque biology. Purpose To evaluate the role of RGS5 on atherosclerotic plaque complexity and shifts of foam cell origin. Methods ApoE-/-RGS5+/+ and ApoE-/-RGS5-/- mice were fed a high fat Western Diet for 14 weeks. Cryosections bearing aortic valve cusps were used for staining. Lesion size was quantified on hematoxylin and eosin staining. Plaque composition was assessed by CD68, CD45, Oil red O and collagen staining. Triple staining was performed for CD45, CD68 and aSMA. Double immunofluorescent staining for CD45 and pro- and anti-inflammatory markers was carried out. Co-Localisation was analysed by Zeiss Zen. Data were analysed using Mann-Whitney-U test. Results Lesion size was significantly reduced in RGS5-deficient mice in comparison to control (in mm2: 0.398±0.02 vs 0.191±0.09, p=0.0001, n=15). Relative areas positive for Oil Red O and collagen did not differ between genotypes. Area positive for leukocyte marker CD45 increased significantly by 30.8% (p<0.0001, n=15), whereas area positive for CD68 was reduced by 10.3% (p=0.0292, n=15) in RGS5-deficient mice. Absence of RGS5 decreased co-localization of Mϕ-derived foam cells by 23% (p=0.03734, n=4-5) while leading to an 5.8% increase in aSMA-derived foam cells compared to control. Area positive for pro-inflammatory M1 Mϕ marker CD86 and iNOS increased by 36.3% and 36.8% after RGS5 knock-out (p<0.0001, n=15). No difference in M2 Mϕ positive area was observed when RGS5 was lacking. Conclusion RGS5 promotes plaque formation. The number of Mϕ-derived foam cells is increased by RGS5, while it reduces inflammatory M1 Mϕ. Interestingly, there were no differences in numbers of M2 Mϕ, indicating RGS5 inhibits VSMCs transition to M1 Mϕ resulting in an overall decrease of CD68-positive foam cells. Further study is required to determine molecular signalling of RGS5 that modulates the phenotype of Mϕ- and VSMC-derived cells. RGS5 could be useful as therapeutic target to suppress undesirable plaque phenotypes and to reduce acute cardiovascular events.

The safety and efficacy of treprostinil for the treatment of pulmonary arterial hypertension: a systematic review and meta-analysis of randomized controlled trials

Abstract Introduction Pulmonary arterial hypertension (PAH) is a severe and life-threatening condition characterized by increased pulmonary vascular resistance and elevated mean pulmonary artery pressure. Treprostinil, a prostacyclin analog, has vasodilatory and anti-remodeling effects on pulmonary arterial smooth muscle cells, indicating promising benefits in enhancing exercise capacity, improving hemodynamics, and reducing morbidity in patients with PAH. Aim The primary objective of this systematic review and Meta-analysis is to assess the efficacy and safety of Treprostinil in patients with PAH. Methods We systematically searched PubMed, Scopus, Cochrane CENTRAL, and ClinicalTrials.gov from inception until July 2023. Randomized controlled trials comparing Treprostinil with Placebo were selected. We used the mean values to compare continuous data and odds ratio (OR) for dichotomous outcomes with their 95% confidence interval (CI). Results We included 7 studies with a total of 2,447 patients. The Treprostinil group was favored over the control group in terms of 6-minute walk distance (6MWD) (Mean difference (MD), meters (m)) (MD = 15.16 m, 95% confidence interval (CI) (10.42 – 19.90 )). Subgroup analysis based on the route of administration revealed a 6MWD of (MD = 13.55 m (95% CI (7.82 – 19.28)) for oral administration and (MD = 17.49 m, 95% CI (6.01 – 28.89)) for intravenous (IV)/subcutaneous (SC) administration, indicating enhanced exercise capacity. When evaluating the efficacy of Treprostinil for oral administration, there was a slight but non-significant trend toward functional improvement (Odds Ratio (OR): 1.36; 95% CI: 0.95 to 1.93) and no significant change in maintaining functional status (OR: 0.94; 95% CI: 0.59 to 1.51). In terms of functional deterioration, the risk was also not significantly reduced (OR: 0.84; 95% CI: 0.36 to 1.98). Safety assessment of the drug was based on clinical, mortality, and adverse events outcomes. Clinically, Treprostinil demonstrated a protective effect against disease progression, evidenced by a reduced risk of clinical worsening (OR: 0.69; 95% CI: 0.52 to 0.91). Mortality rates were not significantly impacted by Treprostinil addition (OR: 0.95; 95% CI: 0.57 to 1.58 for oral, 0.80; 95% CI: 0.32 to 1.98 for IV/SC). However, the incidence of adverse events was notably higher among Treprostinil-treated patients, particularly with oral administration. Conclusion The addition of Treprostinil therapy for patients with PAH significantly improved exercise capacity, as evidenced by an increase in the 6MWD compared to control groups and demonstrated a reduced risk of clinical worsening. The incidence of adverse events was higher among Treprostinil-treated patients, especially with oral administration, potentially impacting quality of life.Forest plot of the 6MWD

Suppression of Fibulin 5 Attenuated Pulmonary Arterial Hypertension Associated with Congenital Heart Disease via Mitigating Pulmonary Arterial Smooth Muscle Cell Dysfunction

Abstract Backgrounds: The specific molecular pathogenesis of pulmonary arterial hypertension associated with congenital heart disease (CHD-PAH) and the reversal still remain elusive. Fibulin 5 was involved in the regulation of cardiovascular system while little is known about the expression and functions of fibulin 5 in the development of CHD-PAH. This study aimed to investigate the role of fibulin 5 in the pathogenesis of the disease. Methods Lung samples were obtained both from patients with CHD-PAH and aortocaval shunt-associated PAH rat models. TGF-β1was used to induce human pulmonary artery smooth muscle cells (hPASMCs) dysfunction and lentiviruses were responsible for alteration of fibulin 5 expression. In an effort to explore the specific role of fibulin 5, an inhibitor of phosphatidylinositol-3-kinases (PI3K) /protein-serine-threonine kinase (AKT) which was defined as the TGF-β1-related downstream signaling was applied for further exploration. Results Fibulin 5 was pronouncedly elevated in the PASMCs of the remodeled pulmonary arterioles from patients with CHD-PAH and shunt-associated PAH rats. We found that over-expression of fibulin 5 could promote hPASMCs dysfunction induced by TGF-β1 and it could be reversed by the PI3K/AKT inhibitor LY294002 suggesting the essential role of TGF-β1/PI3K/AKT signaling activation in phenotypic switch, proliferation and migration of PASMCs. Moreover, an adeno-associated virus vector encoding fibulin 5 by intratracheally instillation with rats improve the hemodynamic parameters in shunt-associated PAH rats and its related pulmonary artery remodeling. Conclusion Over-expression of fibulin 5 could significantly promote hPASMCs dysfunction and pulmonary artery remodeling via reinforcing TGF-β1/PI3K/AKT signaling activation, which highlighted the potential valuable pharmacological target for the treatment of CHD-PAH.Fibulin 5 was over-expressed in PAHInhibition of fibulin 5 attenuated PAH

Itga9 protects against thoracic aortic aneurysm or dissection

Abstract Background The thoracic aortic aneurysm or dissection (TAAD) is a fatal cardiovascular disease with unclear pathogenic mechanisms. Integrins are important in coordinating the transmembrane connections between the extracellular matrix (ECM) and cytoskeleton, contributing to pathological processes of various diseases. Integrin α9 (Itga9), one of the integrin family subunits, has emerged as critical for vascular homeostasis. However, the contribution of Itga9 to TAAD remains elusive. Purpose The present study aimed to determine the role of Itga9 in the development of TAAD and its underlying mechanisms. Methods Western blotting and immunofluorescence staining were used to evaluate ITGA9 expression in the human Standford-A AAD tissues and rodent model of TAAD. Beta-aminopropionitrile monofumarate (BAPN) was used to induce TAAD mouse model. Vascular smooth muscle cell (VSMC)-specific Itga9 knockout mice or adeno-associated virus (AAV)-treated Itga9 overexpressed mice were generated to detect the role of Itga9 in the progression of TAAD. RNA-sequencing analysis was performed to discern possible transcriptome changes in the aorta tissues of VSMC-specific Itga9 knockout mice after BAPN treatment. Primary mouse aortic VSMC culture, flow cytometry analysis, EdU incorporation assay, transmission electron microscopy, and autophagy flux experiments were performed to evaluate the function of Itga9 on VSMCs and uncover its downstream target. Results ITGA9 expression levels were reduced in the aorta tissues of Standford-A AAD patients and BAPN-induced TAAD mice. VSMC-specific deletion of Itga9 exacerbated the incidence of BAPN-induced TAAD in mice. Itga9 deficiency downregulated Valosin-containing protein (Vcp) expression in mice aorta and caused reduced autophagy biomarkers of LC3 after BAPN treatment. In the primary aortic VSMCs, Itga9 deficiency resulted in repressed autophagy, accelerated apoptosis, and reduced proliferation ability. Mechanistically, Itga9 recruited the transcription factor Pre-B-cell leukemia transcription factor 1 (Pbx1) to activate the Vcp and promote VSMC autophagy. Consistently, overexpression of Itga9 in vitro and in vivo rescued the autophagic change and protected against the TAAD progression by upregulating the expression of Pbx1 and Vcp. Conclusions Our findings indicate a critical role of Itga9 in the regulation of VSMC autophagy by controlling Pbx1-Vcp. The Itga9-Pbx1-Vcp axis may represent a novel therapeutic target against TAAD.

PEDF upregulated in Ngfr-positive cells suppresses proliferation of pulmonary artery smooth muscle cells

Abstract Background Pulmonary arterial hypertension (PAH) is a disease with poor prognosis that causes right heart failure due to progressive pulmonary artery remodeling. Although existing pulmonary vasodilators contribute to pulmonary artery reverse remodeling by reducing share stress, the development of therapeutic agents that directly target pulmonary vascular remodeling is desired. Nerve growth factor receptor (Ngfr) is involved in the inflammatory reaction and repair process of damaged tissues. We have previously reported that Ngfr-positive cells are increased in the peripheral blood (PB) of PAH patients and are associated with disease progression. We also found that Ngfr inhibited the pathogenetic progression of pulmonary hypertension in a model of hypoxia-induced pulmonary hypertension. However, it remains unclear how Ngfr positive cells are involved in the pathology of PAH. Purpose In this study, we investigate how Ngfr-positive cells affect the pathogenesis of PAH. Methods & Results To evaluate the localization of Ngfr-positive cells in lung tissue, WT mice (C57BL/6) transplanted with bone marrow (BM) of GFP-Tg mice were kept under hypoxia for 3 weeks to create hypoxia-induced pulmonary hypertension (PH) model. Immunostaining of lung tissue sections indicated that double positive cells (Ngfr+GFP+) were present in the interstitial tissue around the small pulmonary artery. To examine the cellular characteristics of Ngfr-positive cells, RNA sequencing of Ngfr-positive and Ngfr-negative cells in PB was performed. Significantly 78 genes were upregulated in Ngfr-positive cells, including 11 secreted proteins. Among these, we focused on pigment epithelium-derived factor (PEDF), a secreted protein involved in angiogenesis. PEDF mRNA expression was decreased in the lung of Ngfr-KO mice compared to WT mice. We next examined the effect of PEDF on pulmonary artery smooth muscle cells (PASMCs). Platelet-derived growth factor (PDGF)-induced cell proliferation of PASMC was inhibited by PEDF stimulation. Furthermore, PEDF stimulation significantly inhibited PDGF-induced mRNA expressions of TNF and MMP9 in PASMCs. Conclusion In this study, we show that PEDF expression is upregulated in Ngfr-positive cells and that PEDF inhibits PDGF-induced hPASMC proliferation, suggesting that NGFR-positive cells may suppress pulmonary vascular remodeling through PEDF-mediated paracrine effects. PEDF might be a new therapeutic target for PH.

Human coronary blood single-cell sequencing combined with exosome proteomic profiling reveals the molecular mechanism of recurrent in-stent restenosis (R-ISR)

Abstract Background Percutaneous coronary intervention (PCI) is recognized as the core treatment for symptomatic myocardial ischemia and acute coronary syndrome (ACS). However, the complex pathogenesis of recurrent in-stent restenosis (R-ISR) after stent implantation is still insufficiently understood. Purpose This study reports the first single-cell RNA sequencing and proteomic profiling to characterize pathogenesis of R-ISR in humans. Methods To reveal the pathophysiology and molecular mechanism of R-ISR, we performed single-cell RNA sequencing to identify RISR-induced changes in transcriptional landscape in coronary blood mononuclear cell composition. Besides, proteomic profiling of human coronary plasma-derived exosomes was used to further screen different proteins. Transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western blot analysis were performed to identify exosomes. In vitro cell biology experiments were used to validate the discoveries of bioinformatics analysis. Results Compared with normal subjects, the percentage of FCGR3B high monocytes, memory T cells and plasmacytoid dendritic cells (DCs) was increased in R-ISR. Furthermore, we observed a marked increase in the expression of JUN, FOS, CXCL8, S100A8 enriched in the IL-17 signaling pathway that is known to play a crucial role in activating inflammation, mediating immune response, and even maintaining inflammation to chronicity. According to in vitro experiments, the co-cultured system demonstrated that FCGR3B high monocytes isolated from RISR patients activated the expression of inflammatory factors in endothelial cells (ECs), such as IL-1β, IL-6 and TNF-α. Inflammatory activated endothelial cells could release a large amount of exosomes, proteomic profiling of exosomes isolated from ECs observed a significant upregulation of MYLK expression, which could promote proliferation and migration of vascular smooth muscle cells (VSMCs) by activating VEGFR-2 signaling pathway. Conclusions Our study reveals a novel subset of FCGR3B high monocytes in R-ISR patients that could activate ECs inflammation via IL-17 signaling pathway. Activated ECs release exosomes rich in MYLK, which promote proliferation and migration of VSMCs, ultimately leading to repeated restenosis.

Metabolic alterations in human pulmonary artery smooth muscle cells treated with PDGF-BB.

Metabolic abnormalities are considered to play a key regulatory role in vascular remodeling of pulmonary arterial hypertension. However, to date, there is a paucity of research documenting the changes in metabolome profiles within the supernatants of pulmonary artery smooth muscle cells (PASMC) during their transition from a contractile to a synthetic phenotype. CCK-8 and Edu staining assays were used to evaluate the cell viability and proliferation of human PASMCs. IncuCyte ZOOM imaging system was used to continuously and automatically detect the migration of the PASMCs. A targeted metabolomics profiling was performed to quantitatively analyze 121 metabolites in the supernatant. Orthogonal partial least squares discriminant analysis was used to discriminate between PDGF-BB-induced PASMCs and controls. Metabolite set enrichment analysis was adapted to exploit the most disturbed metabolic pathways. Human PASMCs exhibited a transformation from contractile phenotype to synthetic phenotype after PDGF-BB induction, along with a significant increase in cell viability, proliferation, and migration. Metabolites in the supernatants of PASMCs treated with or without PDGF-BB were well profiled. Eleven metabolites were found to be significantly upregulated, whereas seven metabolites were downregulated in the supernatants of PASMCs induced by PDGF-BB compared to the vehicle-treated cells. Fourteen pathways were involved, and pyruvate metabolism pathway was ranked first with the highest enrichment impact followed by glycolysis/gluconeogenesis and pyrimidine metabolism. Significant and extensive metabolic abnormalities occurred during the phenotypic transformation of PASMCs. Disturbance of pyruvate metabolism pathway might contribute to pulmonary vascular remodeling.

Parathyroid hormone exacerbates pulmonary hypertension via parathyroid hormone receptors on pulmonary artery smooth muscle cells

Abstract Background Pulmonary hypertension (PH) is a right heart failure disease and can be fatal. Parathyroid hormone (PTH) is a bone metabolism hormone and regulates calcium and phosphorus homeostasis. Previous studies have suggested that PTH affects the cardiovascular system and influences cardiovascular diseases. We hypothesized that PTH may play a role in the pathogenesis of PH. Purpose This study aimed to investigate whether PTH has a critical role in pulmonary hemodynamics. Method Serum PTH levels were measured in patients with PH or suspected PH undergoing right heart catheterization. We tested whether the regulation of PTH and the PTH receptor (PTH1R) affected PH in hypoxia (Hx)-induced PH model mice and Sugen/hypoxia (SuHx)-induced PH model ras. Hx mice were treated with PTH daily for 3 weeks or with an inhaled AAV-shRNA system to knockdown PTH1R expression in the lung. SuHx rats underwent parathyroidectomy (PTx). We measured physical data and right ventricular systolic pressure (RVSP) in these models. Human pulmonary artery smooth muscle cells (PASMCs) were cultured and treated with PTH to examine the direct effects of PTH. Result In the clinical study, we enrolled 30 participants and found serum PTH levels correlated with mean pulmonary artery pressure (r = 0.67) and pulmonary vascular resistance (r = 0.62). The ROC curve showed a cut-off PTH level of 46.0 pg/mL (68.2% sensitivity, 100% specificity) to predict PH. In animal models, PTH treatment exacerbated right ventricular hypertrophy and increased right ventricular systolic pressure (RVSP) in Hx mice compared with non-treated Hx mice (Figure 1). In contrast, knockdown of PTH1R in the lungs improved PH in Hx mice, and PTx significantly suppressed PH in SuHx rats (Figure 2). PTH promoted migration and proliferation through PTH receptor-ERK signaling in PASMCs. Conclusion Our clinical and experimental data showed that PTH exacerbates PH and suggest that PTH/PTH1R signaling would be a new target for PH treatment.

Inhibiting chondroitin sulfate synthase 1 ameliorates hyperplastic arterial remodelling

Abstract Introduction Hyperplastic arterial remodelling is characterized by intima-media thickening, lumen narrowing, inflammation and increased extracellular matrix (ECM) deposition. Chondroitin sulfate (CS) glycosaminoglycans, the unbranched polysaccharide chains of proteoglycans, are important components of ECM. We previously found CS accumulated in adversely remodelled heart and artery, aggravating cardiac deterioration. Objective We aim to explore a therapeutic strategy to interfere with CS synthesis and investigate its potential in ameliorating hyperplastic arterial remodelling. Methods Through single-cell RNA sequencing of non-cardiomyocytes cardiac cells from mouse myocardial infarction model, chondroitin sulfate synthase 1 (CHSY1) was identified as the primary CS synthase and was increased during disease progression. A Chsy1 knockout (KO) mouse strain was generated. Fibrosis and arterial remodelling were induced using: (i) 4 weeks of angiotensin II/phenylephrine (AngII/PE) infusion through subcutaneous osmotic minipumps; and (ii) transverse aortic constriction surgery. To assess the therapeutic potential of CHSY1 inhibition in ameliorating hyperplastic arterial remodelling, Chsy1 was knockdown by dsiRNA post disease onset. Mechanism of action was investigated using primary vascular smooth muscle cells (VSMCs). Results Chsy1 KO reduced CS and its stereoisomer dermatan sulfate in the heart to 42 ± 22% and 36 ± 7% respectively, whereas other types of glycosaminoglycans remain intact. KO mice were protected against phenotypes of hyperplastic arterial remodelling induced by the two disease models in both the coronary and carotid arteries. For example, 90.1% of coronary arterial fibrosis and 79.7% of macrophage infiltration induced by AngII/PE was declined in KO mice compared to WT mice, while cardiac function as stroke volume was augmented by 41.3%. Concomitantly, carotid arterial wall thickening was lower by 36.5% and distensibility was higher by 36.7%, validating Chsy1 as a potent target. As a therapeutic approach, weekly intravenous injection of dsiRNA achieved Chsy1 reduced to 30.2 ± 5.5% in the carotid artery and 72.5 ± 4.7% in the heart. Post disease onset, Chsy1 KD therapy reduced fibrosis by 59.9% in the coronary artery (P = 0.006) and improved stroke volume by 25.6% (P = 0.036). The structural integrity and function of carotid arteries were well-reserved, manifesting as improved distensibility (29%, P = 0.016), increased elastin/perimeter ratio (15%, P = 0.002), and reduced macrophage infiltration (38%, P = 0.029). In vitro, CHSY1 inhibition suppressed migration and cytokine production of macrophages, fibroblast-to-myofibroblast transition, and VSMC hyperproliferation. NOTCH3 signalling was found to be positively correlated with CHSY1 modulation. Conclusions We demonstrated that inhibiting CHSY1 is necessary and sufficient to block CS synthesis. Chsy1 KD by dsiRNA is an effective therapy to ameliorate hyperplastic arterial remodelling.

Recruitment of CCR5-positive T cells in pulmonary vascular lesions in idiopathic- and connective tissue disease associated- pulmonary arterial hypertension

Abstract Background C-C chemokine receptor type 5 (CCR5) is a chemokine receptor predominantly expressed on leukocytes including T cells, macrophages, and dendritic cells, and is involved in the process by which T cells are attracted to specific tissues and organs. Although CCR5 has been shown to be expressed on macrophages and pulmonary artery smooth muscle cells in lung samples from human idiopathic pulmonary arterial hypertension (PAH) and some animal models, its expression on T cells in human PAH lungs has not been investigated. Purpose To investigate the immunohistochemical expression of CCR5 on T cells infiltrating in pulmonary vascular lesions of human PAH tissues, particularly from patients with idiopathic PAH and PAH associated with connective tissue disease (CTD-PAH), where inflammation has been implicated in the pathogenesis. Methods Subjects included 25 postmortem cases of idiopathic PAH (14 cases, a mean age of 34 ± 10 years, 8 female cases) and CTD-PAH (11 cases, 48 ± 13 years, all female). We performed immunohistochemistry using antibodies against CCR5 and CD3 (for T cells) on formalin-fixed paraffin-embedded sections. To semi-quantify, we selected the three small muscular pulmonary arteries (80-150 µm in external diameter) with the strongest CCR5-positive cell infiltration in each case, counted the number of positive cells, and the average were shown as the number of cells per vessel. Results In all cases, regardless of whether IPAH or CTD-PAH, a subset of infiltrating inflammatory cells into or accumulating around vessels was CCR5-positive. Specifically, CCR5-positive inflammatory cells were found in remodelled pulmonary arteries, such as plexiform lesions and constrictive lesions with intimal thickening and/or medial hypertrophy, as well as perivascular space. The average number of CCR5-positive cells per small muscular pulmonary artery was 8.1/vessel. Where pulmonary venous occlusive lesions were seen, CCR5-positive cells were also present in and around them. The majority of CCR5-positive inflammatory cells appeared to be T cells, based on morphology and CD3 immunopositivity in the serial sections. Conclusion(s) Activated T cells showing CCR5 immunopositivity were recruited to remodelled pulmonary vascular lesions in both idiopathic PAH and CTD-PAH. This implicates CCR5-positive T cells as a common key player and that CCR5 signalling is involved in the pathogenesis of PAH in concert with other inflammatory cells, vascular endothelial cells, and pulmonary artery smooth muscle cells.

Carvedilol suppresses coronary artery spasm in A-kinase anchoring protein 150 knockout mouse

Abstract Backgrounds A-kinase anchoring proteins (AKAPs) act as scaffold to regulate activation of protein kinases and subsequent downstream signaling. AKAP 150 interacts with protein kinase A and protein kinase C, and has a critical role in regulating L-type calcium channel activity. We previously reported enhanced phospholipase C activity as an important mechanism of coronary spastic angina (CSA), known as Prinzmetal’s angina. Coronary artery spasm was induced by intravenous ergometrine injection in mouse model of vascular smooth muscle cell (VSMC)-specific enhanced phospholipase C activity concomitantly with enhanced intracellular Ca2+ concentration ([Ca2+]i). Then, we hypothesized that coronary artery spasm would be inhibited by AKAP 150 knockout, however, coronary artery spasm was unexpectedly induced in AKAP 150 knockout (AKAP-KO) mice without affecting [Ca2+]i, suggesting that AKAP-KO mouse is an unique model of CSA independent of [Ca2+]i. Previous report showed that AKAP-KO mice have a high Ca2+/calmodulin-dependent protein kinase (CaMK) II activity, and carvedilol, a non-selective beta-adrenergic receptor antagonist, inhibits CaMK II activity. Aim We tested the hypothesis that carvedilol could prevent coronary artery spasm via inhibiting CaMK II activity, which is a key molecule to regulate VSMC contraction, in AKAP-KO mice. Methods and Results We pretreated 14-18-weeks-old AKAP-KO mice with intraperitoneal injection of carvedilol (2.5mg/kg), propranolol (20mg/kg), or vehicle (control). Coronary artery spasm, evaluated by ST-segment elevation on lead II of body surface electrocardiogram, was induced by intravenous ergometrine injection (30mg/kg) in all controls (5/5, 100%) and all propranolol-treated mice (5/5, 100%), whereas it tended to be inhibited in carvedilol-treated mice (3/6, 50%) (p=0.08 vs control). In isolated VSMCs obtained from the aorta of AKAO-KO mice, the changes in [Ca2+]i from baseline in response to acetylcholine (ACh, 100μM) did not differ among the groups of pretreatment with carvedilol (10μM), propranolol (10μM), or vehicle, indicating that coronary artery spasm in AKAP-KO mice was induced by Ca2+-independent mechanism. In response to ACh, the phosphorylation of CaMK II was tended to be decreased (p=0.07), and the phosphorylation of myosin light chain was decreased (p<0.05) in VSMCs treated with carvedilol compared with control. Conclusions Carvedilol may inhibit coronary artery spasm probably via inhibiting CaMK II activity in AKAP-KO mice. Our results may provide a new paradigm into the pathogenesis of CSA as a model of enhanced Ca2+ sensitivity and important clinical implications for the mechanism of calcium channel antagonist-refractory coronary artery spasm.

Perspectives on Sotatercept in Pulmonary Arterial Hypertension

Sotatercept acts as a type IIA-Fc activin receptor, thereby scavenging free activin from its physiological membrane receptor. Through this type of action, sotaterpect leads to a rebalancing of the proliferation and antiproliferation pathways of pulmonary smooth muscle cells in response to bone morphogenic protein (BMP). Although sotatercept has been approved as the fourth pillar of therapy for group 1 pulmonary arterial hypertension (PAH) in the United States and Europe, several studies are ongoing to broaden the application of the drug to non-Group 1 PAH. We provide an overview of the clinical and preclinical evidence of targeting the activation pathway by sotatercept in the treatment of PAH. We also discuss other potential applications of sotatercept in the context of pulmonary hypertension other than PAH group 1.

Mechanisms of Bone Morphogenetic Protein 2 in Respiratory Diseases.

Bone morphogenetic protein 2 (BMP2) belongs to the transforming growth factor-β (TGF-β) superfamily and plays an important role in regulating embryonic development, angiogenesis, osteogenic differentiation, tissue homeostasis, and cancer invasion. Increasing studies suggest BMP2 is involved in several respiratory diseases. This study aimed to review the role and mechanisms of BMP2 in respiratory diseases. BMP2 signaling pathway includes the canonical and non-canonical signaling pathway. The canonical signaling pathway is the BMP2-SMAD pathway, and the non-canonical signaling pathway includes mitogen-activated protein kinase (MAPK) pathway and phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway. The BMP2 is related to pulmonary hypertension (PH), lung cancer, pulmonary fibrosis (PF), asthma, and chronic obstructive pulmonary disease (COPD). BMP2 inhibits the proliferation of pulmonary artery smooth muscle cells (PASMCs), promotes the apoptosis of PASMCs to reduce pulmonary vascular remodeling in PH, which is closely related to the canonical and non-canonical pathway. In addition, BMP2 stimulates the proliferation and migration of cells to promote the occurrence, colonization, and metastasis of lung cancer through the canonical and the non-canonical pathway. Meanwhile, BMP2 exert anti-fibrotic function in PF through canonical signaling pathway. Moreover, BMP2 inhibits airway inflammation to maintain airway homeostasis in asthma. However, the signaling pathways involved in asthma are poorly understood. BMP2 inhibits the expression of ciliary protein and promotes squamous metaplasia of airway epithelial cells to accelerate the development of COPD. In conclusion, BMP2 may be a therapeutic target for several respiratory diseases.

Epigenetic modulation of vascular calcification: Looking for comprehending the role of sirt1 and histone acetylation in VSMC phenotypic transition

In light of the complex origins of ectopic vascular calcification and its significant health implications, this study offers a comprehensive exploration of the molecular dynamics governing vascular smooth muscle cells (VSMCs). Focusing on epigenetic modulation, we investigate the transition from a contractile to a calcifying phenotype in VSMCs, with an emphasis on understanding the role of SIRT1. For this purpose, a single batch of human aortic SMCs, used at a specified passage number to maintain consistency, was subjected to calcium and phosphate overload for up to 72 h. Our findings, validated through RT q-PCR, Western blot, immunofluorescence, and DNA methylation analyses, reveal a complex interplay between acetyltransferases and deacetylases during this phenotypic transition. We highlight HAT1A's critical role in histone acetylation regulation and the involvement of HDACs, as evidenced by subcellular localization studies. Moreover, we demonstrate the modulation of SIRT1 expression, a class III deacetylase, during VSMC calcification, underscoring the influence of DNA methylation in this process. Importantly, the study addresses previously unexplored aspects of the dynamic protein expression patterns observed, providing insight into the counterintuitive expressions of key proteins such as Runx2 and osterix. This research underscores the significant impact of epigenetic mechanisms, particularly the modulation of SIRT1, in the transition from a contractile to a calcifying phenotype in VSMCs, offering potential avenues for further exploration in the context of vascular calcification.

A baculoviral gene and drug-eluting (GDES) stent to promote re-endothelialization and prevent restenosis caused by atherosclerosis

Abstract Background Coronary artery disease (CAD) is a prevalent condition affecting approximately one in every 20 individuals over the age of 20, resulting in significant health and economic burdens worldwide. Atherosclerosis, characterized by plaque buildup in the arteries, is a leading cause of CAD, involving endothelial dysfunction, inflammation, and smooth muscle cell hyperproliferation. The standard interventions for CAD, namely bare-metal stents (BMS) or drug-eluting stents (DES), often lead to complications such as blood clotting, inflammation, and arterial re-narrowing, necessitating further interventions and potentially leading to severe outcomes like heart failure, stroke, or death. Additionally, the TGFβ1 gene regulates SMC proliferation and ECM secretion, promoting endothelial cell proliferation, inhibiting smooth muscle cell hyperproliferation, reducing reactive oxygen species production. Purpose This innovative stent aims to mitigate complications associated with conventional stents by promoting endothelial health and preventing inflammation and hyperproliferation downstream. The purpose of this study is to design a new gene and drug eluting stent and evaluate their preclinical efficacy and safety in addressing some of the key limitations of currently available coronary stents. Methods The TGFβ1 expressing baculoviruses loaded PLGA nanoparticles are prepared by double emulsion solvent evaporation method. The formulated nanoparticles were characterized by their surface morphology, particle size, zeta potential, and in vitro release. Moreover, the designed nanoparticles undergo a further investigation for their therapeutic efficiency using cell lines. The GDES is synthesized by dip-coating a BMS into a solution containing Everolimus and genipin carrying baculoviruses expressing TGFβ1 in nanoparticles. The stent elutes the gene and drug over specific durations pertaining to a sustained release profile. The study assesses the functionality and safety of the GDES through in vitro and in vivo experiments, including cell culture studies and animal models. Results The PLGA nanoparticles at 115.3±1.4 nm with a polydipersity (pdi) index of 0.152 have a sustained release profile for the TGFβ1 expressing baculovirus. The findings demonstrate that the GDES effectively promotes endothelial health and prevents inflammation and hyperproliferation downstream. The expression of TGFβ1 facilitates the formation of a fully reconstituted endothelial lining, reducing the risk of complications. Additionally, the prolonged release of Everolimus prevents inflammation and the progression of neointimal hyperplasia. The stent coating and system exhibit non-cytotoxicity and hemocompatibility, ensuring safety during expansion and degradation over time. Overall, the combined action of gene and drug elution in the GDES shows promising results in addressing current complications associated with cardiovascular stents.

Novel balloon catheter containing therapeutic mRNA with smart RNA switch alleviate restenosis after vascular injury

Abstract Background Cardiovascular diseases are the leading cause of death worldwide, and vascular intervention is an effective method for ischemic heart diseases. However, vascular restenosis significantly affects the long-term therapeutic outcomes, which mainly caused by excessive proliferation of vascular smooth muscle cells (VSMCs). While drug-eluting stents and drug-coated balloons have successfully decreased the incidence of restenosis by inhibiting the VSMCs proliferation, they concurrently suppress the repair of endothelial cells (ECs) and re-endothelialization, thereby increasing the risk of late thrombotic events and mortality. Consequently, it is urged to develop novel high-selectively therapeutic devices to overcome vascular restenosis. In current mRNA therapies of cardiovascular diseases, there are few effective systems for cell-specific expression. Therefore, we propose to utilize RNA editing (based on ADAR1 RNA editing) to investigate a smart RNA molecular switch capable of cell-specific recognition and selectively releasing payload in targeted cells or tissues for cell precision therapy. However, the application of gene editing in the cardiovascular system faces challenge of low delivery efficiency. We innovatively take the balloon as a specific and efficient tool to delivery therapeutic mRNA, which may be a potential therapy for vascular restenosis. Objective We investigated therapeutic mRNA containing a smart RNA switch to selectively suppress the VSMCs proliferation while promoting re-endothelialization and delivered by balloon as a novel therapy in vascular restenosis animal models. Results For RNA switch high-throughput screening, we utilized PiggyBac transposon system to establish monoclonal overexpressing cell lines and chose the cell strain with expression levels closely mimicking VSMCs and ECs. We found the most effective RNA switch from dozens of potential candidates which could specifically recognize VSMCs but not ECs. Therapeutic mRNA sequences containing the RNA switch efficiently initiated payload translation in VSMCs while maintaining payload silence in primary vascular endothelial cells, which effectively and selectively inhibited VSMCs excessive proliferation and promoted endothelial repair. Additionally, we developed an interventional balloon delivery system for mRNA drugs, achieving in situ delivery to cardiovascular lesions in vivo, demonstrating therapeutic effects consistent with cellular phenotypes in animal models. Conclusion We suggest that the smart RNA switch can serve as a novel, cell-specific therapeutic tool for restenosis and other cardiovascular diseases. Additionally, utilizing a balloon for mRNA delivery represents a new paradigm for mRNA therapy and gene editing in the cardiovascular field.

Retraction Note: Long noncoding RNA CASC2 inhibits ox-LDL-mediated vascular smooth muscle cells proliferation and migration via the regulation of miR-532-3p/PAPD5

Retraction Note: Long noncoding RNA CASC2 inhibits ox-LDL-mediated vascular smooth muscle cells proliferation and migration via the regulation of miR-532-3p/PAPD5

Targeting an altered sphingolipid profile with consecutive lipotoxicity as therapeutic approach to calcific aortic valve disease

Abstract Background Aortic stenosis due to calcific aortic valve disease (CAVD) is the most common valvular heart disease. In symptomatic patients, without repair the prognosis is poor. Treatment to date is based on surgery or catheter-based interventions. Pharmacological therapy options to prevent the progression of valve calcification are not available. In vascular smooth muscle cells, cellular accumulation of sphingolipids is associated with a proinflammatory response in the sense of lipotoxicity. Chronic inflammatory processes are indeed also essential for aortic valve calcification. Purpose With the subsequent goal of developing innovative treatment approaches for CAVD, we therefore aim to elucidate the unclear role of sphingolipids in the development of CAVD. Methods Human aortic valve and plasma samples of CAVD patients and controls (n=26) were analysed by liquid chromatography–mass spectrometry for lipidomics and proteomics. Human aortic valve interstitial cells (hVICs) were stimulated with ceramides. Calcification was detected by alizarin red staining. mRNA expression of bone-related proteins was determined by qPCR. NF-kB pathway was assessed by proteome profiler. Myriocin and GW4869 were applied to inhibit ceramide biosynthesis. PDTC and MCC950 were used to inhibit NF-kB Pathway and NLRP3 activation. ApoE-/- mice received a gain-of-function PCSK9 adeno-associated virus vector and fed high cholesterol diet for 14 weeks. Myriocin was applied orally over the treatment period to inhibit ceramide de novo synthesis in vivo. Murine echocardiography was used to measure transvalvular velocity and left ventricular function. Calcification degree of murine aortic valve was determined by histological staining. Results A significantly altered sphingolipid profile was observed in aortic valve tissue of CAVD patients (Fig. 1). Ceramide species e.g. Cer (17:1;2O/16:0) were increased. Verifying the biological relevance of these findings in vitro, C2-Cer (d18:1/2:0) enhanced hVIC calcification (Fig. 2). Accordingly, ALP activity and mRNA expression of osteogenic genes RUNX2, ALPL and MSX2 were increased. Furthermore, C2-Cer (d18:1/2:0) enhanced NF-kB p65 phosphorylation and NLRP3 activation, while treatment with both PDTC and MCC950 protected against C2-Cer (d18:1/2:0) induced calcification. Supporting the role of sphingolipid biosynthesis in hVIC calcification, Myriocin and GW4869 both reduced ox-LDL-induced VIC calcification which was reversed by C2-Cer(d18:1/2:0). Finally, Myriocin reduced the degree of calcification and transvalvular jet velocity of aortic valve in the PCSK9-AAV ApoE-/- mice model. Conclusion CAVD is accompanied by an accumulation of ceramides causing lipotoxicity in human aortic valve tissue. Pharmacological modulation of sphingolipid metabolism is an effective approach to prevent the development and progression of aortic valve calcification in vivo and should be considered as a future therapeutic strategy in CAVD patients.Volcano Plot of CAVD tissue lipidomicsC2 Ceramide enhances hVIC calcification