Smooth Muscle Proliferation Research Articles

Transcriptomic and Metabolomic Insights into Age-Related Changes in Lung Tissue of Yaks Under Highland Stress

As an indigenous species on the Tibetan Plateau, the yak is well adapted to the plateau hypoxic environment. The high-altitude hypoxia adaptation of the yak requires the adaptive reshaping of multiple tissues and organs, especially the lungs. To reveal the adaptive development of yak lungs under hypoxic stress at the tissue and molecular levels, we conducted histomorphological observations as well as transcriptomic and metabolomic studies of yak lungs at three ages (0.5, 2.5, and 4.5 years). The results showed that the lung tissue developed significantly with age. The mean alveolar area was higher (p < 0.01) in 4.5 and 2.5-year-old yaks than in 0.5-year-old yaks. The percentage of elastic fibers, micro-arterial wall thickness, and micro-arterial area showed an increasing trend (p < 0.01) from 0.5-year-old yaks to 2.5-year-old yaks and then to 4.5-year-old yaks. In addition, some critical differentially expressed genes related to angiogenesis (MYC, EPHA2, TNF), fiber formation (EREG), smooth muscle proliferation (HBEGF), erythropoiesis (SOCS3), and hypoxia response (ZFP36) were identified. Some metabolites associated with these genes were also found simultaneously. These findings provide a deeper understanding of the molecular strategies underlying this species’ extraordinary ability to survive normally in low-oxygen environments. In conclusion, the lungs of yaks undergo continuous adaptive development under hypoxic stress, and these findings are crucial for understanding the molecular mechanisms by which native species of the Tibetan Plateau survive in harsh environments.

Total alkaloids in Fritillaria cirrhosa D. Don alleviate OVA-induced allergic asthma by inhibiting M2 macrophage polarization

Fritillaria cirrhosa D. Don (FCD) is a traditional Chinese medicine used to treat respiratory disorders, known for its effects in clearing heat, moistening the lungs, resolving phlegm, and relieving cough. Additionally, the total alkaloids extracted from FCD can alleviate asthma symptoms and reduce airway inflammation. However, no studies have investigated the effects of total alkaloids on lung macrophages. This study explored whether the total alkaloids of FCD (TAs-FCD) reduce M2 macrophage polarization and, consequently, attenuate airway remodeling in asthmatic mice. This study further elucidated its mechanism of action in treating allergic asthma. The extracted TAs-FCD was analyzed for its composition using UPLC-Q-TOF/MS. Network pharmacology was employed to identify the active ingredients and potential mechanisms of TAs-FCD in the treatment of allergic asthma. A mouse model of ovalbumin-induced allergic asthma was established, adopted, and validated through in vivo experiments. Hematoxylin-eosin staining (H&E), immunohistochemistry (IHC), immunofluorescence staining (IF), enzyme-linked immunosorbent assay (ELISA), Western blotting (WB), and real-time fluorescence quantitative polymerase chain reaction (q-PCR) were used to investigate the role of TAs-FCD in inhibiting M2 macrophage polarization in the context of allergic asthma. A total of 66 active ingredients were screened from 116 compounds using SWISSADME. The targets of these 66 compounds were predicted by SwissTargetPrediction, resulting in 808 unique drug targets after excluding duplicates. Additionally, 1,756 targets related to allergic asthma were identified from the DisGeNET, Genecard, and OMIM databases. This led to 267 cross-targets between the active ingredient targets and allergic asthma targets, including interleukin (IL)-1β, tumor necrosis factor (TNF), and STAT3. Animal experiments demonstrated that TAs-FCD improved histopathological injury in mouse lungs, reduced peri-airway collagen fiber accumulation, airway mucus secretion, and airway smooth muscle proliferation. TAs-FCD also lowered IL-1β, TNF-α and IL-4 levels in lung tissues and alleviated airway inflammation. Furthermore, TAs-FCD significantly reduced levels of Arg1 and CD206, which are closely associated with M2 macrophages, and downregulated the expression of p-STAT3 and p-JAK2. TAs-FCD may inhibit M2 macrophage polarization by regulating the JAK2/STAT3 pathway, thereby alleviating airway remodeling and inflammation in allergic asthmatic mice.

Quantitative MRI in children with Crohn's disease - where do we stand?

Crohn's disease (CD) is a chronic inflammatory condition that affects the gastrointestinal tract, particularly the ileum and colon. This disease is characterized by recurrent bouts of intestinal inflammation with subsequent bowel wall damage, including scarring (i.e., fibrosis) and abnormal smooth muscle proliferation. MR enterography, an MRI examination tailored to assess the small bowel, is a first-line diagnostic tool for diagnosing CD in children, characterization and monitoring of disease severity and extent, and assessment of disease-related complications. To date, such MRI evaluations have been mostly qualitative, which can adversely impact diagnostic performance and inter-radiologist agreement. Quantitative MRI methods have been shown to aid in the evaluation of a variety of medical conditions and have been increasingly investigated in children and adults with CD. In CD, such objective techniques have been used to assist with diagnosis, assess treatment response, and characterize bowel wall histologic abnormalities. In the current work, we will review quantitative MRI methods for detecting and measuring intestinal active inflammation (MRI-based scoring systems, T1 relaxation mapping, diffusion-weighted imaging, intra-voxel incoherent motion, mesenteric phase contrast), bowel wall damage (magnetization transfer), and motility (quantitative cine imaging) in small bowel CD, with an emphasis on the pediatric population.

PH-sensing GPR68 inhibits vascular smooth muscle cell proliferation through Rap1A.

Phenotypic transformation of vascular smooth muscle (VSM) from a contractile state to a synthetic, proliferative state is a hallmark of cardiovascular disease (CVD). In CVD, diseased tissue often becomes acidic from altered cellular metabolism secondary to compromised blood flow, yet the contribution of local acid/base imbalance to the disease process has been historically overlooked. In this study, we examined the regulatory impact of the pH-sensing G protein-coupled receptor GPR68 on vascular smooth muscle (VSM) proliferation in vivo and in vitro in wild-type (WT) and GPR68 knockout (KO) male and female mice. Arterial injury reduced GPR68 expression in WT vessels and exaggerated medial wall remodeling in GPR68 KO vessels. In vitro, KO VSM cells showed increased cell cycle progression and proliferation compared to WT VSM cells, and GPR68-inducing acidic exposure reduced proliferation in WT cells. mRNA and protein expression analyses revealed increased Rap1A in KO cells compared to WT cells, and RNA silencing of Rap1A reduced KO VSM cell proliferation. In sum, these findings support a growth-inhibitory capacity of pH-sensing GPR68 and suggest a mechanistic role for the small GTPase Rap1A in GPR68-mediated VSM growth control. These results shed light on GPR68 and its effector Rap1A as potential targets to combat pathologic phenotypic switching and proliferation in VSM.

Association of hsCRP and Serum Kalirin Levels with the Development and Severity of Premature Coronary Artery Disease in Iraqi Patients

Background: Coronary artery disease (CAD) is a major contributor to morbidity and mortality worldwide. Early-onset CAD, also known as PCAD, is a severe form of CAD associated with high mortality and a poor prognosis. Early diagnosis is crucial to reducing complications. While hsCRP is an established biomarker for CAD, kalirin is a potential novel biomarker due to its role in promoting smooth muscle proliferation and endothelial dysfunction. Objective: To evaluate the relationship between serum kalirin and hsCRP levels with the presence and severity of PCAD and to compare the diagnostic value of both biomarkers. Method: The study recruited 92 participants into two groups: the PCAD group (46) included patients with confirmed CAD by angiographic findings and the second group was the non-CAD group (46) with negative findings by coronary angiography. The levels of serum kalirin and hsCRP were measured for both groups using enzyme-linked immunosorbent assay (ELISA) kits. Results: Serum levels of kalirin and hsCRP were strongly associated with the presence of PCAD (p<0.001), and both biomarkers were associated with disease severity (p=0.002, <0.001, respectively). ROC analysis showed that hsCRP possesses a slight advantage (AUC=0.796) over kalirin (ROC=0.717) as a diagnostic marker for PCAD. Conclusions: Serum kalirin and hsCRP levels are associated with PCAD and with the severity of the disease, both markers possess moderate diagnostic capabilities for PCAD with a slight advantage for hsCRP.

Ligation-assisted endoscopic submucosal resection following unroofing technique for small esophageal subepithelial lesions originating from the muscularis propria.

The majority of esophageal subepithelial lesions originating from the muscularis propria (SEL-MPs) are benign in nature, although a subset may exhibit malignant characteristics. Conventional endoscopic resection techniques are time-consuming and lack efficacy for small SEL-MPs. To evaluate the efficacy and safety of ligation-assisted endoscopic submucosal resection (ESMR-L) following unroofing technique for small esophageal SEL-MPs. From January 2021 to September 2023, 17 patients diagnosed with esophageal SEL-MPs underwent ESMR-L following unroofing technique at the endoscopy center of Shenzhen People's Hospital. Details of clinicopathological characteristics and clinical outcomes were collected and analyzed. The mean age of the patients was 50.12 ± 12.65 years. The mean size of the tumors was 7.47 ± 2.83 mm and all cases achieved en bloc resection successfully. The average operation time was 12.2 minutes without any complications. Histopathology identified 2 Lesions (11.8%) as gastrointestinal stromal tumors at very low risk, 12 Lesions (70.6%) as leiomyoma and 3 Lesions (17.6%) as smooth muscle proliferation. No recurrence was found during the mean follow-up duration of 14.18 ± 9.62 months. ESMR-L following roofing technique is an effective and safe technique for management of esophageal SEL-MPs smaller than 20 mm, but it cannot ensure en bloc resection and may require further treatment.

Comparison of efficacy and safety of sarpogrelate-based anti-platelet therapy with clopidogrel-based anti-platelet therapy following arterial endovascular therapy: A systematic review

Objective: Sarpogrelate is a selective serotonin/5-hydroxytryptamine 2A receptor antagonist used in the management of peripheral artery disease (PAD). The drug has emerged as a promising choice for medical management post-endovascular therapy (EVT) due to its anti-platelet aggregation, vasoconstriction, and anti-vascular smooth muscle proliferation properties. The aim of the meta-analysis is to evaluate the efficacy and safety of sarpogrelate-based APT following arterial EVTs in PAD. Material and Methods: PubMed, Google Scholar, Scopus, and the Cochrane were systematically searched from inception to December 2023. Any randomized controlled trial studies in English that evaluated the efficacy and safety of sarpogrelate-based APT after EVT in patients with PAD was included. Data on the restenosis rate, target lesion revascularization (TLR), and safety parameters were extracted and studied. The pooled differences in efficacy and safety parameters between sarpogrelate-based APT and non-sarpogrelate-based APT was calculated using the relative risk (RR) with a 95% CI. Results: A total of three randomized controlled trials were included out of 354 articles obtained through a literature search. No significant differences were observed in the risk of restenosis (RR=0.74, 95% C.I.= 0.55- 1.00, P=0.954) and TLR (RR=0.76, 95% C.I.= 0.47- 1.23 , P=0.476) among patients being treated with sarpogrelate and non-sarpogrelate based APT. Likewise, sarpogrelate-based APT had similar safety profile as non-sarpogrelate-based APT. Conclusion: Sarpogrelate-based APT can be considered an effective alternative to clopidogrel-based conventional APT after EVTs. However, there is a huge need for a larger multicenter, multinational, and multiethnic global trial with sufficient participants in order to produce generalizable findings.

Epstein-Barr Virus-Associated Smooth Muscle Tumor After Kidney Transplantation: A French Multicenter Retrospective Study.

Epstein-Barr virus (EBV) is a herpesvirus linked to nine different human tumors and lymphoproliferative disorders. Immunosuppression promotes EBV-driven malignancies. The most frequent EBV-induced malignancies are lymphomas and nasopharyngeal carcinoma. By promoting smooth muscle proliferation, EBV can induce EBV-associated smooth muscle tumors (EBV-SMT). EBV-SMT is a rare oncological entity for which no current guideline for diagnosis or management exists. Data on posttransplant EBV-SMT (PT-SMT) are scarce in kidney transplant recipients. We conducted a national multicentric retrospective study and collected cases among transplantation centers in France. Kidney transplant recipients experiencing histologically proven PT-SMT were included. We collected data on demographic characteristics of patient, history of kidney transplantation, history of PT-SMT, evolution of graft function, and patient survival. Eight patients were included. The median age at PT-SMT diagnosis was 31 years (range 6.5-40). PT-SMT occurred after a median delay of 37.8 months after transplantation (range 6-175). PT-SMT management consisted in immunosuppressive regimen minimization in all patients. Introduction of mTOR inhibitors was performed in two patients. Four patients (50%) needed chemotherapy. Surgical resection was performed in four patients. At last follow-up after PT-SMT diagnosis (median 33 months (range 17-132)), five patients were considered in complete remission, and two patients had died. Two patients experienced graft rejection; two resumed dialysis (25%). All patients with available data presented with impaired graft function at last follow-up. PT-SMT is a subacute and progressive disease during kidney transplantation. Even if the risk of developing PT-SMT is low in kidney transplant recipients (0.07% in our cohort), PT-SMT is associated with significant graft loss, possibly due to reduced immunosuppression. Developing guidelines could help transplantation teams better manage these patients.

Evaluation of Nicorandil in Treatment of induced pulmonary arterial hypertension in male Rats

Pulmonary arterial hypertension (PAH) is a chronic, rare, and non-treatable disease, resulting in elevated mean arterial pressure (≥25mmHg) during rest and (≥30mmHg) during exercise. Pulmonary arteries remodeling including endothelial apoptosis, smooth muscle hyperplasia, and endothelial dysfunction are distinct features of PAH. This study aims to evaluate effect of nicorandil as an alternative treatment for PAH in comparison to tadalafil by evaluating its anti-inflammatory effect and histopathological changes. A total of 60 male wistar rats were divided to 6 groups, a control healthy group, and another 5 groups injected with monocrotaline to induce PAH. The induction group was left untreated while the other 4 groups were treated with either nicorandil or tadalafil, with or without treatment blockers (N-Nitroarginine methyl ester and glimepiride), after 21 days they were sacrificed for histopathology and measurement of inflammatory markers. Nicorandil reduced the levels of osteopontin, and cardiac marker brain natriuretic peptide (BNP) significantly (P≤0.05) , also it showed an improved histopathological picture of PAH by reducing smooth muscle proliferation, necrosis, and inflammation in pulmonary arteries. In conclusion, nicorandil in this study showed promising results in reducing inflammation and improving endothelial function.

A rare case of a vascular benign tumor in oral cavity – Case report

Leiomyomas are benign tumors arising from smooth muscle and can be classified as solid, epithelioid, and vascular leiomyoma (angioleiomyoma). Angioleiomyoma frequently occurs on the skin. Due to the lack of smooth muscle in the oral cavity, this tumor is rarely located in the mouth. This study aims to present a rare case of a 36-year-old woman with a painless submucosal nodule in the left cheek mucosa, measuring approximately 2 cm x 1 cm, with 5-years of evolution. Morphological and histochemical examination evidenced the proliferation of smooth muscle around the blood vessels of various calibers. The diagnosis of angioleiomyoma was confirmed, the tumor was surgically removed, and the patient had no further complications after 9-months of follow-up. The diagnosis of oral angioleiomyoma is challenging since this tumor is rare and can mimic or transform into malignancy. For this reason, histological examination in association with immunohistochemical is invaluable to establishing an accurate diagnosis and delivering suitable treatment.

Atherosclerosis associated with Chlamydia pneumoniae: Dissecting the etiology

Chlamydia pneumoniae related infections and atherosclerosis are both common entities. Today, the literature presents an enormous amount of data regarding the role of C. pneumoniae in the development and sustainment of atherosclerosis and allowing us to comprehend the molecular mechanisms behind better. The implications of C. pneumoniae in atherogenesis include altered platelet function, hypercoagulability, macrophage dysfunction, vascular smooth muscle proliferation, and increased neutrophilic migration. Therefore, it would not be wrong to implicate that, C. pneumoniae plays important roles in almost every stage of atherogenesis. Furthermore, various serological markers suggestive of active or past C. pneumoniae infection are known to be associated with multiple clinical presentations, such as abdominal aortic aneurysms, subclinical atherosclerosis in the young individuals, aggravated atherosclerosis in heterozygous familial hypercholesterolemia. This review, as a result, aims to provide detailed insights into the pathophysiological mechanisms of atherogenesis associated with C. pneumoniae and its clinical implications.

Diacylglycerol kinase is a keystone regulator of signaling relevant to the pathophysiology of asthma.

Signal transduction by G protein-coupled receptors (GPCRs), receptor tyrosine kinases (RTKs) and immunoreceptors converge at the activation of phospholipase C (PLC) for the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) into inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). This is a point for second-messenger bifurcation where DAG via protein kinase C (PKC) and IP3 via calcium activate distinct protein targets and regulate cellular functions. IP3 signaling is regulated by multiple calcium influx and efflux proteins involved in calcium homeostasis. A family of lipid kinases belonging to DAG kinases (DGKs) converts DAG to phosphatidic acid (PA), negatively regulating DAG signaling and pathophysiological functions. PA, through a series of biochemical reactions, is recycled to produce new molecules of PIP2. Therefore, DGKs act as a central switch in terminating DAG signaling and resynthesis of membrane phospholipids precursor. Interestingly, calcium and PKC regulate the activation of α and ζ isoforms of DGK that are predominantly expressed in airway and immune cells. Thus, DGK forms a feedback and feedforward control point and plays a crucial role in fine-tuning phospholipid stoichiometry, signaling, and functions. In this review, we discuss the previously underappreciated complex and intriguing DAG/DGK-driven mechanisms in regulating cellular functions associated with asthma, such as contraction and proliferation of airway smooth muscle (ASM) cells and inflammatory activation of immune cells. We highlight the benefits of manipulating DGK activity in mitigating salient features of asthma pathophysiology and shed light on DGK as a molecule of interest for heterogeneous diseases such as asthma.

Management of Benign Prostatic Hyperplasia in 2024

Benign prostatic hyperplasia (BPH) is a condition involving the proliferation of smooth muscle and epithelial cells within the transition zone of the prostate. The process by which this takes place is not precisely known. It does require that testosterone and 5-alpha reductase convert it to dihydrotestosterone (DHT) which is the active androgen within the prostate. The growth of the prostate results from an imbalance between cell growth and cell death. Obstruction occurs via compression of the urethra by the resulting hyperplastic nodules, as well as increased smooth muscle tone and resistance within the enlarged gland. It is an almost universal process in men beginning in their 40’s; it increases to a prevalence of 60% by age 60 and 80% by age 80.1 This results in progressive bladder outlet obstruction (BOO) and lower urinary tract symptoms (LUTs). Patients can range from being asymptomatic to severely symptomatic. In the most extreme cases, it can result in complete urinary retention and renal dysfunction. The annual economic impact of BPH has been estimated at nearly $4 billion in the Unites States.

Identification of oxidative phosphorylation-related genes in moyamoya disease by combining bulk RNA-sequencing analysis and machine learning.

Introduction: Moyamoya disease (MMD) is a chronic cerebrovascular disease that can lead to ischemia and hemorrhagic stroke. The relationship between oxidative phosphorylation (OXPHOS) and MMD pathogenesis remains unknown. Methods: The gene expression data of 60 participants were acquired from three Gene Expression Omnibus (GEO) datasets, including 36 and 24 in the MMD and control groups. Differentially expressed genes (DEGs) between MMD patients MMD and control groups were identified. Machine learning was used to select the key OXPHOS-related genes associated with MMD from the intersection of DEGs and OXPHOS-related gene sets. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), gene set enrichment analysis (GSEA), Immune infiltration and microenvironments analysis were used to analyze the function of key genes. Machine learning selected four key OXPHOS-related genes associated with MMD: CSK, NARS2, PTPN6 and SMAD2 (PTPN6 was upregulated and the other three were downregulated). Results: Functional enrichment analysis showed that these genes were mainly enriched in the Notch signaling pathway, GAP junction, and RNA degradation, which are related to several biological processes, including angiogenesis, proliferation of vascular smooth muscle and endothelial cells, and cytoskeleton regulation. Immune analysis revealed immune infiltration and microenvironment in these MMD samples and their relationships with four key OXPHOS-related genes. APC co-inhibition (p = 0.032), HLA (p = 0.001), MHC I (p = 0.013), T cellco- inhibition (p = 0.032) and Type I IFN responses (p < 0.001) were significantly higher in the MMD groups than those in the control groups. The CSK positively correlated with APC co-inhibition and T cell-co-inhibition. The NARS2 negatively correlated with Type I IFN response. The SMAD2 negatively correlated with APC co-inhibition and Type I IFN response. The PTPN6 positively correlated with HLA, MHC I and Type I IFN responses. Discussion: This study provides a comprehensive understanding of the role of OXPHOS in MMD and will contribute to the development of new treatment methods and exploration of MMD pathogenesis.

THE SUCCESS OF ND-YAG LASER IN THE TREATMENT OF VENOUS MALFORMATIONS OF THE ORAL MUCOSA ABOUT TWO CASES

Venous malformations are the result of errors in endothelial cell morphogenesis, causing disorganized angiogenesis and intimal smooth muscle proliferation. (1) This results in the formation of dilated networks of venous lakes that are hemodynamically non-functional. (1,2) Depending on location, they may go unnoticed for years prior to presentation, and range from asymptomatic superficial varicosities to large deforming craniofacial lesions. The management of venous malformation will depend on the localization and expansion of the malformation, and there are multiple therapeutic approaches: sclerotherapy, surgery, and medical management. Lasers, another modality for treating VMs. we report two casesof success with the Nd Yag laser in the treatment ofsuperficialvenous malformations the oral mucosa.

Multiple anaplastic lymphoma kinase-positive primary inflammatory myofibroblastic tumors with spontaneously expanding and shrinking nodules in both lungs: a case report

BackgroundInflammatory myofibroblastic tumors (IMTs) are uncommon neoplasms most prevalent in individuals under 40 years old and predominantly in the lungs. Despite their rarity, multiple anaplastic lymphoma kinase (ALK)-positive IMTs, especially those of various sizes, have not been widely reported. This report describes a case of multiple ALK-positive IMTs in the lungs, aiming to further our understanding of their behavior and management.Case presentationHerein, we present the case of a 64-year-old woman who presented with an abnormal shadow on chest examination. Chest computed tomography revealed a main tumor in the right middle lobe and multiple irregularly shaped small nodules in both lungs. Thus, thoracoscopic wedge resection of the left lower lobe was performed for diagnosis. Pathological findings indicated smooth muscle proliferation without malignancy. IMT was diagnosed following thoracoscopic right middle lobectomy. Twenty months postoperatively, one residual nodule shrank, but another grew.ConclusionsThis is the first report of multiple ALK-positive IMTs in both lungs, highlighting the need for definitive diagnosis and treatment of IMTs based on surgical resection. Although caution is required in patients with lymph node metastases or distant metastases, careful follow-up is acceptable unless there is a tendency for nodules to increase in size on imaging.

Analysis of MicroRNA Cargo in Circulating Extracellular Vesicles from HIV-Infected Individuals with Pulmonary Hypertension.

The risk of developing pulmonary hypertension (PH) in people living with HIV is at least 300-fold higher than in the general population, and illicit drug use further potentiates the development of HIV-associated PH. The relevance of extracellular vesicles (EVs) containing both coding as well as non-coding RNAs in PH secondary to HIV infection and drug abuse is yet to be explored. We here compared the miRNA cargo of plasma-derived EVs from HIV-infected stimulant users with (HIV + Stimulants + PH) and without PH (HIV + Stimulants) using small RNA sequencing. The data were compared with 12 PH datasets available in the GEO database to identify potential candidate gene targets for differentially altered miRNAs using the following functional analysis tools: ingenuity pathway analysis (IPA), over-representation analysis (ORA), and gene set enrichment analysis (GSEA). MiRNAs involved in promoting cell proliferation and inhibition of intrinsic apoptotic signaling pathways were among the top upregulated miRNAs identified in EVs from the HIV + Stimulants + PH group compared to the HIV + Stimulants group. Alternatively, the downregulated miRNAs in the HIV + Stimulants + PH group suggested an association with the negative regulation of smooth muscle cell proliferation, IL-2 mediated signaling, and transmembrane receptor protein tyrosine kinase signaling pathways. The validation of significantly differentially expressed miRNAs in an independent set of HIV-infected (cocaine users and nondrug users) with and without PH confirmed the upregulation of miR-32-5p, 92-b-3p, and 301a-3p positively regulating cellular proliferation and downregulation of miR-5571, -4670 negatively regulating smooth muscle proliferation in EVs from HIV-PH patients. This increase in miR-301a-3p and decrease in miR-4670 were negatively correlated with the CD4 count and FEV1/FVC ratio, and positively correlated with viral load. Collectively, this data suggest the association of alterations in the miRNA cargo of circulating EVs with HIV-PH.

NKX2-5 regulates vessel remodeling in scleroderma-associated pulmonary arterial hypertension.

NKX2-5 is a member of the homeobox-containing transcription factors critical in regulating tissue differentiation in development. Here, we report a role for NKX2-5 in vascular smooth muscle cell phenotypic modulation in vitro and in vascular remodeling in vivo. NKX2-5 is upregulated in scleroderma patients with pulmonary arterial hypertension. Suppression of NKX2-5 expression in smooth muscle cells halted vascular smooth muscle proliferation and migration, enhanced contractility, and blocked the expression of extracellular matrix genes. Conversely, overexpression of NKX2-5 suppressed the expression of contractile genes (ACTA2, TAGLN, CNN1) and enhanced the expression of matrix genes (COL1) in vascular smooth muscle cells. In vivo, conditional deletion of NKX2-5 attenuated blood vessel remodeling and halted the progression to hypertension in a mouse chronic hypoxia model. This study revealed that signals related to injury such as serum and low confluence, which induce NKX2-5 expression in cultured cells, is potentiated by TGF-β and further enhanced by hypoxia. The effect of TGF-β was sensitive to ERK5 and PI3K inhibition. Our data suggest a pivotal role for NKX2-5 in the phenotypic modulation of smooth muscle cells during pathological vascular remodeling and provide proof of concept for therapeutic targeting of NKX2-5 in vasculopathies.

Characterization of PDGF-Induced Subcellular Calcium Regulation through Calcium Channels in Airway Smooth Muscle Cells by FRET Biosensors

The homeostasis of cellular calcium is fundamental for many physiological processes, while the calcium levels remain inhomogeneous within cells. During the onset of asthma, epithelial and inflammatory cells secrete platelet-derived growth factor (PDGF), inducing the proliferation and migration of airway smooth muscle (ASM) to the epidermal layer, narrowing the airway. The regulation of ASM cells by PDGF is closely related to the conduction of calcium signals. In this work, we generated subcellular-targeted FRET biosensors to investigate calcium regulation in the different compartments of ASM cells. A PDGF-induced cytoplasmic calcium [Ca2+]C increase was attributed to both extracellular calcium influx and endoplasmic reticulum (ER) calcium [Ca2+]ER release, which was partially regulated by the PLC-IP3R pathway. Interestingly, the removal of the extracellular calcium influx led to inhibited ER calcium release, likely through inhibitory effects on the calcium-dependent activation of the ER ryanodine receptor. The inhibition of the L-type calcium channel on the plasma membrane or the SERCA pump on the ER resulted in both reduced [Ca2+]C and [Ca2+]ER from PDGF stimulation, while IP3R channel inhibition led to reduced [Ca2+]C only. The inhibited SERCA pump caused an immediate [Ca2+]C increase and [Ca2+]ER decrease, indicating active calcium exchange between the cytosol and ER storage in resting cells. PDGF-induced calcium at the outer mitochondrial membrane sub-region showed a similar regulatory response to cytosolic calcium, not influenced by the inhibition of the mitochondrial calcium uniporter channel. Therefore, our work identifies calcium flow pathways among the extracellular medium, cell cytosol, and ER via regulatory calcium channels. Specifically, extracellular calcium flow has an essential function in fully activating ER calcium release.

Machine Learning of Plasma Proteomics Classifies Diagnosis of Interstitial Lung Disease.

Rationale: Distinguishing connective tissue disease-associated interstitial lung disease (CTD-ILD) from idiopathic pulmonary fibrosis (IPF) can be clinically challenging. Objectives: To identify proteins that separate and classify patients with CTD-ILD and those with IPF. Methods: Four registries with 1,247 patients with IPF and 352 patients with CTD-ILD were included in analyses. Plasma samples were subjected to high-throughput proteomics assays. Protein features were prioritized using recursive feature elimination to construct a proteomic classifier. Multiple machine learning models, including support vector machine, LASSO (least absolute shrinkage and selection operator) regression, random forest, and imbalanced Random Forest, were trained and tested in independent cohorts. The validated models were used to classify each case iteratively in external datasets. Measurements and Main Results: A classifier with 37 proteins (proteomic classifier 37 [PC37]) was enriched in the biological process of bronchiole development and smooth muscle proliferation and immune responses. Four machine learning models used PC37 with sex and age score to generate continuous classification values. Receiver operating characteristic curve analyses of these scores demonstrated consistent areas under the curve of 0.85-0.90 in the test cohort and 0.94-0.96 in the single-sample dataset. Binary classification demonstrated 78.6-80.4% sensitivity and 76-84.4% specificity in the test cohort and 93.5-96.1% sensitivity and 69.5-77.6% specificity in the single-sample classification dataset. Composite analysis of all machine learning models confirmed 78.2% (194 of 248) accuracy in the test cohort and 82.9% (208 of 251) in the single-sample classification dataset. Conclusions: Multiple machine learning models trained with large cohort proteomic datasets consistently distinguished CTD-ILD from IPF. Many of the identified proteins are involved in immune pathways. We further developed a novel approach for single-sample classification, which could facilitate honing the differential diagnosis of ILD in challenging cases and improve clinical decision making.