Coronary Artery Smooth Muscle Research Articles

Abstract 4116603: Interleukin-33 from Necrotic Tunica Media Plays a Key Role in the Exacerbations of Coronary Arteritis in Kawasaki Disease

Objective: Alarmins resulting from cell death or oxidative stress have been shown to be involved in the development of Kawasaki disease (KD) vasculitis. In our previous study, we demonstrated the potential role of (IL)-33 as an alarmin in the development of KD vasculitis. Although edematous dissociation (necrotic change) of the tunica media is thought to be a major source of IL-33 in KD vasculitis, it has not yet been elucidated. Methods: We investigated the impact of IL-33 released from necrotic human coronary artery smooth muscle cells (HCASMCs) on human coronary artery endothelial cells (HCAECs) by a co-culture assay using the Transwell ® cell culture insert system. Subsequently, we evaluated the anti-inflammatory effects of anti-IL-33 and anti-ST2 antibodies compared to the conventional therapies of KD, such as high-dose IgG or anti-tumor necrosis factor (TNF)-α antibody. Results: Primary necrosis of HCASMCs induced significant release of IL-33. In co-cultures of necrotic HCASMCs with HCAECs, necrotic HCASMCs significantly induced the production of various proinflammatory cytokines in HCAECs. Anti-IL-33 and anti-ST2 antibodies exhibited unique inhibitory effects on the production of platelet-derived growth factor-BB or IL-12(p70) in HCAECs. Conclusion: The results of the present study suggest the potential involvement of edematous dissociation of the tunica media in the development of KD vasculitis. Furthermore, the distinctive anti-inflammatory effects of the anti-IL-33/ST2 axis drugs suggest novel therapeutic options for patients with refractory KD.

In vitro regenerative effects of a pooled pathogen-reduced lyophilized human cord blood platelet lysate for wound healing applications.

Cord blood platelets, easily obtained from blood units not suitable for haematopoietic stem cell transplantation, represent an abundant source of growth factors for use in wound healing. Although several protocols have been described for platelet lysate production, no standard manufacturing protocol is available. The use of pooled cord blood platelets could thus facilitate standardization. In this study, the effect of varying concentrations (up to 20%) of a pooled pathogen-reduced lyophilized cord blood platelet lysate (PRL-CBPL) was investigated in different cell types involved in the wound healing process. The effect of heparin addition was also evaluated. In parallel, a comparison was performed with a single donor cord blood platelet lysate (SD-CBPL). The effect of PRL-CBPL on the viability and proliferation of different cell lines (L929 mouse fibroblasts and HaCaT keratinocytes) and human primary cells (fibroblasts-NHDF, coronary artery smooth muscle cells-HCASMC and coronary artery endothelial cells-HCAEC), on HaCaT migration and the chemotactic effect on human monocytes (THP-1) was evaluated. PRL-CBPL showed a lower PDGF-AB amount compared to SD-CBPL. Differing concentrations of both CBPL were necessary to influence cell viability and proliferation. 3% was the optimal concentration for L929 and HaCaT as well as for NHDF and HCASMC, while HCAEC required 10%. The effect of added heparin was more evident on SD-CBPL and in particular on NHDF and HCASMC proliferation. Keratinocyte scratch closure was obtained with 3 and 5% PRL-CBPL and SD-CBPL respectively. Both CBPLs caused an increase in the number of migrated THP-1 monocytes in a concentration-dependent manner up to 20% with a higher monocyte migration for SD-CBPL with respect to PRL-CBPL and in cells treated with heparin. The data obtained suggest that PRL-CBPL is an effective standardized alternative to SD-CBPL.

Second-generation antipsychotic quetiapine blocks voltage-dependent potassium channels in coronary arterial smooth muscle cells.

Voltage-dependent K+ (Kv) channels play an important role in restoring the membrane potential to its resting state, thereby maintaining vascular tone. In this study, native smooth muscle cells from rabbit coronary arteries were used to investigate the inhibitory effect of quetiapine, an atypical antipsychotic agent, on Kv channels. Quetiapine showed a concentration-dependent inhibition of Kv channels, with an IC50 of 47.98 ± 9.46 μM. Although quetiapine (50 μM) did not alter the steady-state activation curve, it caused a negative shift in the steady-state inactivation curve. The application of 1 and 2Hz train steps in the presence of quetiapine significantly increased the inhibition of Kv current. Moreover, the recovery time constants from inactivation were prolonged in the presence of quetiapine, suggesting that its inhibitory action on Kv channels is use (state)-dependent. The inhibitory effects of quetiapine were not significantly affected by pretreatment with Kv1.5, Kv2.1, and Kv7 subtype inhibitors. Based on these findings, we conclude that quetiapine inhibits Kv channels in both a concentration- and use (state)-dependent manner. Given the physiological significance of Kv channels, caution is advised in the use of quetiapine as an antipsychotic due to its potential side effects on cardiovascular Kv channels.

Fast and reliable quantification of aldosterone, cortisol and cortisone via LC-MS/MS to study 11β-hydroxysteroid dehydrogenase activities in primary cell cultures

Cell culture experiments can support characterization of enzymatic activities in healthy and tumorous human tissues. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) enables simultaneous measurement of several steroids from a single sample, facilitating analysis of molecular pathways involved in steroid biosynthesis. We developed a reliable but fast method for quantification of cortisol, cortisone and aldosterone in cell culture supernatant. Validation, including investigation of matrix-matched calibration, was performed for two different cell types. Utility of the method was demonstrated in the study of 11β-hydroxysteroid dehydrogenase type 2 (HSD11B2) activity under conditions of glucocorticoid and mineralocorticoid excess in different cell types. Aldosterone, cortisol and cortisone were extracted by liquid-liquid extraction (LLE) with methyl tert-butyl ether from 1 mL of cell culture supernatant. Steroids were separated on a Kinetex biphenyl column (50 ×2.1 mm, 2.6 µm) with gradient elution of water and methanol containing 2 mM ammonium format and analysed in multiple reaction monitoring mode after positive electrospray ionization. Application of the method included cell culture experiments with two different primary cell types, human coronary artery smooth muscle cells (HCSMC) and human coronary artery endothelial cells (EC). Cells were treated with different concentrations of cortisol, aldosterone and mifepristone, a glucocorticoid receptor antagonist and quantitative PCR was performed. The method exhibits high precision (CV ≤ 6 %) and accuracy (deviation from nominal concentration ≤ 6 %) for concentrations above the limit of quantification (LoQ) which is 0.11, 0.56 and 0.69 nmol/L for aldosterone, cortisone and cortisol, respectively. Calibration curves did not differ when prepared in media or solvent. The method enabled us to confirm activity of HSD11B2 and concentration dependent conversion of cortisol to cortisone in HCSMC (median conversion ratio at 140 nM cortisol = 1.46 %). In contrast we did not observe any HSD11B2 activity in EC. Neither addition of high aldosterone, nor addition of 1 µM mifepristone had impact on glucocorticoid concentrations. Quantitative PCR revealed expression of HSD11B1 and HSD11B2 in HCSMC but not in EC. We present a fast and reliable method for quantification of cortisol, cortisone and aldosterone in cell culture supernatants. The method enabled us to study HSD11B2 activity in two different cell types and will support future experiments investigating mechanisms of target organ damage in conditions of glucocorticoid and mineralocorticoid excess.

Necrotic Change of Tunica Media Plays a Key Role in the Development of Coronary Artery Lesions in Kawasaki Disease.

Alarmins resulting from cell death or oxidative stress are involved in the development of Kawasaki disease (KD) vasculitis. In a previous study, we demonstrated the potential role of interleukin (IL)-33 as an alarmin in the development of KD vasculitis. Although edematous dissociation (necrotic change) of the tunica media is thought to be a major source of IL-33 in KD vasculitis, it has not yet been elucidated. We investigated the impact of IL-33 released from necrotic human coronary artery smooth muscle cells (HCASMCs) on human coronary artery endothelial cells (HCAECs) using a coculture assay. Subsequently, we evaluated the anti-inflammatory effects of anti-IL-33 and anti-suppression of tumorigenicity 2 (ST2) antibodies compared with conventional therapies of KD, such as high-dose IgG or anti-tumor necrosis factor (TNF)-α antibody. Primary necrosis of HCASMCs induced significant release of IL-33. In cocultures of necrotic HCASMCs with HCAECs, the necrotic HCASMCs significantly induced the production of various proinflammatory cytokines in the HCAECs. Anti-IL-33 and anti-ST2 antibodies exhibited unique inhibitory effects on the production of platelet-derived growth factor-BB or IL-12(p70) in HCAECs. There is potential involvement of edematous dissociation of the tunica media in the development of KD vasculitis. Furthermore, the distinctive anti-inflammatory effects of the anti-IL-33/ST2 axis drugs suggest novel therapeutic options for patients with refractory KD.

Abstract Tu010: Matrix metallopeptidase 9 contributes to the beginning of plaque and is a potential biomarker for the early identification of atherosclerosis in asymptomatic patients with diabetes

Aims: To determine the roles of matrix metallopeptidase-9 (MMP9) on human coronary artery smooth muscle cells (HCASMCs) in vitro , early beginning of atherosclerosis in vivo in diabetic mice, and patients with diabetes. Methods: Active hMMP9 ( act-hMMP9) was added to HCASMCs and markers of inflammation were measured. Act-hMMP9 (n=16) or placebo (n=15) was administered to d i abetic KK.Cg- A y /J (KK) mice. Carotid artery inflammation and atherosclerosis measurements were made at 2 and 10 weeks after treatment. An observational study of newly diagnosed drug naïve patients with type 2 diabetes mellitus (T2DM n=234) and healthy matched controls (n=41) was performed and patients had ultrasound of carotid arteries and some had coronary computed tomography angiogram for the assessment of atherosclerosis. Serum MMP9 was measured and its correlation with carotid artery or coronary artery plaques were determined. Results: Act-hMMP9 induced inflammatory response in HCASMCs in vitro , including increased gene and protein expressions of MCP-1, ICAM-1, VCAM-1, and enhanced macrophage adhesion. Exogenous act-hMMP9 increased inflammation and initiated atherosclerosis in KK mice at 2 and 10 weeks: increased vessel wall thickness, lipid accumulation, and Galectin-3+ macrophage infiltration into the carotid arteries. In newly diagnosed T2DM patients, serum MMP9 correlated with carotid artery plaque size with a possible threshold cutoff point. In addition, serum MMP9 correlated with number of mixed plaques and grade of lumen stenosis in coronary arteries of patients with drug naïve T2DM. Conclusions: MMP9 contributes to the initiation of atherosclerosis and may be a potential biomarker for the early identification of atherosclerosis in patients with diabetes

Integrated analysis of differentially m6A modified and expressed lncRNAs for biomarker identification in coronary artery disease.

N6-methyladenosine (m6A) is the most prevalent internal RNA modification in mammals. However, limited research has been conducted on the role of m6A in coronary artery disease (CAD). We conducted methylated RNA immunoprecipitation sequencing and RNA sequencing to obtain a genome-wide profile of m6A-modified long noncoding RNAs (lncRNAs) in human coronary artery smooth muscle cells either exposed to oxidized low-density lipoprotein treatment or not, and the characteristics of the expression profiles were explored using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. The predictive effects of seven selected lncRNAs on CAD were evaluated in peripheral blood mononuclear cells (PBMCs). The differentially m6A-modified and expressed lncRNAs related genes were predominantly enriched in small GTPase-mediated signal transduction, ErbB signaling, and Rap1 signaling. Additionally, the expression levels of uc003pes.1, ENST00000422847, and NR_110155 were significantly associated with CAD, with uc003pes.1 identified as an independent risk factor and NR_110155 as an independent protective factor for CAD. NR_110155 and uc003pes.1 in PBMCs have the potential to serve as biomarkers for predicting CAD.

Selective mural cell recruitment of pericytes to networks of assembling endothelial cell-lined tubes.

Mural cells are critically important for the development, maturation, and maintenance of the blood vasculature. Pericytes are predominantly observed in capillaries and venules, while vascular smooth muscle cells (VSMCs) are found in arterioles, arteries, and veins. In this study, we have investigated functional differences between human pericytes and human coronary artery smooth muscle cells (CASMCs) as a model VSMC type. We compared the ability of these two mural cells to invade three-dimensional (3D) collagen matrices, recruit to developing human endothelial cell (EC)-lined tubes in 3D matrices and induce vascular basement membrane matrix assembly around these tubes. Here, we show that pericytes selectively invade, recruit, and induce basement membrane deposition on EC tubes under defined conditions, while CASMCs fail to respond equivalently. Pericytes dramatically invade 3D collagen matrices in response to the EC-derived factors, platelet-derived growth factor (PDGF)-BB, PDGF-DD, and endothelin-1, while minimal invasion occurs with CASMCs. Furthermore, pericytes recruit to EC tube networks, and induce basement membrane deposition around assembling EC tubes (narrow and elongated tubes) when these cells are co-cultured. In contrast, CASMCs are markedly less able to perform these functions showing minimal recruitment, little to no basement membrane deposition, with wider and shorter tubes. Our new findings suggest that pericytes demonstrate much greater functional ability to invade 3D matrix environments, recruit to EC-lined tubes and induce vascular basement membrane matrix deposition in response to and in conjunction with ECs.

Identification of an osteopontin-derived peptide that binds neuropilin-1 and activates vascular repair responses and angiogenesis

The osteopontin-derived peptide FOL-005 stimulates hair growth. Using ligand-receptor glyco-capture technology we identified neuropilin-1 (NRP-1), a known co-receptor for vascular endothelial growth factor (VEGF) receptors, as the most probable receptor for FOL-005 and the more stable analogue FOL-026. X-ray diffraction and microscale thermophoresis analysis revealed that FOL-026 shares binding site with VEGF in the NRP-1 b1-subdomain. Stimulation of human umbilical vein endothelial cells with FOL-026 resulted in phosphorylation of VEGFR-2, ERK1/2 and AKT, increased cell growth and migration, stimulation of endothelial tube formation and inhibition of apoptosis in vitro. FOL-026 also promoted angiogenesis in vivo as assessed by subcutaneous Matrigel plug and hind limb ischemia models. NRP-1 knock-down or treatment of NRP-1 antagonist EG00229 blocked the stimulatory effects of FOL-026 on endothelial cells. Exposure of human coronary artery smooth muscle cells to FOL-026 stimulated cell growth, migration, inhibited apoptosis, and induced VEGF gene expression and VEGFR-2/AKT phosphorylation by an NRP-1-dependent mechanism. RNA sequencing showed that FOL-026 activated pathways involved in tissue repair. These findings identify NRP-1 as the receptor for FOL-026 and show that its biological effects mimic that of growth factors binding to the VEGF receptor family. They also suggest that FOL-026 may have therapeutical potential in conditions that require vascular repair and/or enhanced angiogenesis.

MicroRNA-31-5p is upregulated during neointima formation and influences human coronary artery smooth muscle cell functions by regulating PIAS3 and DKK1

Abstract Funding Acknowledgements None. Background and purpose MicroRNAs (miRs) have emerged as potential therapeutic targets in cardiovascular disease, given their ability to modulate multiple signaling pathways and cellular processes. Neointima formation as an angioplasty-related complication remains a major issue calling for innovative therapeutic options and is predominantly mediated by phenotypic and functional changes of vascular smooth muscle cells. Here, we propose that targeting miR-31-5p might be an effective approach to selectively modulate smooth muscle cell functions to enhance vascular healing and regeneration. Methods C57J/BlL6 mice (n=6, 3 months, male) were subjected to wire-induced femoral artery injury. At days 10 and 21 after injury, femoral arteries were harvested for miRNA analysis. Expression levels of miR-31-5p were confirmed by qRT-PCR in human coronary artery endothelial cells (HCAEC) and -smooth muscle cells (HCASMC). Further, the effect of miR-31-5p on cellular functions was investigated on HCAECs and HCASMCs in vitro, including migration (scratch assay), proliferation (BrdU assay), and apoptosis. Possible targets of miR-31-5p were identified in silico by structured literature research and target binding prediction and confirmed on mRNA and protein levels. High-resolution microscopy analysis was used to investigate morphological changes. Results Expression analysis revealed a significant upregulation of miR-31-5p (p<0.0001) in murine femoral artery neointimal tissue at 7 and 21 days. In vitro, miR-31-5p was significantly upregulated in HCASMC (p<0,05) but not HCAEC following serum stimulation. On a functional level, miR-31-5p revealed dissenting effects on HCAEC and HCASMC. Whereas migration and proliferation are not altered in HCAECs, knockdown of miR-31-5p significantly reduced migration (p<0,01), proliferation (p<0,05), and increased apoptosis (p<0,05) in HCASMCs. Additionally, the knockdown of miR-31-5p influenced the phenotypical switch of HCASMC towards a contractile phenotype. Under these conditions, the release of cytokines like TNF-alpha and IL1-beta was also significantly reduced (p<0,05) in HCASMCs. Systematic in silico target screens suggested DKK1 and PIAS3 as potential direct targets. Indeed, knockdown of miR-31-5p resulted in a significant upregulation of DKK1 in HCASMC (p<0,05) on mRNA level and DKK1 (p<0,05) and PIAS3 (p<0,05) on mRNA and protein level. An overexpression resulted in a significant downregulation of DKK1 in HCASMC (p<0,05) on mRNA level. Conclusion In conclusion, we report that miR-31-5p is robustly upregulated during neointima formation and seems to exert a functional neointima formation-promoting role in HCASMC rather than HCAEC. Mechanistically, DKK1 and PIAS3 as direct targets of miR-31-5p can mediate the observed effects. Thus, miR-31-5p might represent an attractive target to selectively modulate HCASMC dysfunction following vascular intervention, limiting neointima formation in treated vessels.

MiRNA-221 and -222 increase in exosomes upon insulin stimulation of human vascular smooth muscle cells lacking the insulin-like growth factor 1 receptor

As a result of increased vascular inflammation, patients with Type 2 diabetes experience a near 4-fold increase in their risk for heart attack and stroke. miR-221 and -222 are two microRNAs that are upregulated in the vasculature of Type 2 diabetic patients. miR-221/222 act by downregulating the cyclin-dependent kinase inhibitor, p27Kip1, in vascular smooth muscle cells (VSMCs) and exosome-mediated proinflammatory effects on endothelial cells and macrophages. Loss of the insulin-like growth factor receptor (IGFR) in VSMCs can unmask the insulin receptor (IR) and increase insulin signaling. We have demonstrated that the loss of IGFR, coupled with physiological insulin stimulation, promotes an increased expression of miR-221/-222 in murine VSMCs. Respectively, miR-221/222 content in VSMC-derived exosomes increases and p27Kip1 mRNA expression decreases in VSMCs. We asked whether the effect of loss of IGFR in human coronary artery smooth muscle cells (HCASMCs) would also lead to an increase in miR-221/-222 content of VSMC-derived exosomes. Transfection with a CRISPR-cas9 plasmid targeting IGFR resulted in a 50% decrease in IGFR mRNA in HCASMCs, when compared to transfection with negative control CRISPR plasmids. Droplet digital PCR was used to measure expression of miR-221 and miR-222 in the exosomes derived from both sets of HCASMCs. There was no change in the miR-221/222 content of exosomes derived from HCASMCs transfected with the negative control CRISPR following stimulation with 1nM insulin (7.27± 4.75 vs. 11.33 ± 1.09 copies of miR-221 and 6.43 ± 0.43 vs. 4.68 ± 0.02 copies of miR-222). In contrast, there was a 2 to 3-fold increase in miR-221/222 content in exosomes that were derived from HCASMCs with IGFR knockdown following stimulation with 1nM insulin (14.96 ± 0.3 vs. 35.66 ± 3.08 copies of miR-221 and 9.12 ± 1.19 vs.15.44 ± 5.36 copies of miR-222). We conclude that loss of IGFR coupled with physiological insulin stimulation increases the miR-221/222 content of exosomes of HCASMCs, recapitulating the effects of IGFR loss seen in murine VSMCs as well as the effects of diabetes on VSMCs. This model system will allow additional studies connecting the loss of IGFR to the cardiovascular complications of diabetes. Tulane University School of Medicine, Biomedical Sciences Program. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Inhibition of voltage-gated potassium channel by aripiprazole in rabbit coronary arterial smooth muscle cells

Aripiprazole, a third-generation antipsychotic, has been widely used to treat schizophrenia. In this study, we evaluated the effect of aripiprazole on voltage-gated potassium (Kv) channels in rabbit coronary arterial smooth muscle cells using the patch clamp technique. Aripiprazole reduced the Kv current in a concentration-dependent manner with a half-maximal inhibitory concentration of 0.89 ± 0.20 μM and a Hill coefficient of 1.30 ± 0.25. The inhibitory effect of aripiprazole on Kv channels was voltage-dependent, and an additional aripiprazole-induced decrease in the Kv current was observed in the voltage range of full channel activation. The decay rate of Kv channel inactivation was accelerated by aripiprazole. Aripiprazole shifted the steady-state activation curve to the right and the inactivation curve to the left. Application of a repetitive train of pulses (1 and 2 Hz) promoted inhibition of the Kv current by aripiprazole. Furthermore, the recovery time constant from inactivation increased in the presence of aripiprazole. Pretreatment of Kv1.5 subtype inhibitor reduced the inhibitory effect of aripiprazole. However, pretreatment with Kv 7 and Kv2.1 subtype inhibitors did not change the degree of aripiprazole-induced inhibition of the Kv current. We conclude that aripiprazole inhibits Kv channels in a concentration-, voltage-, time-, and use (state)-dependent manner by affecting the gating properties of the channels.

Matrix metallopeptidase 9 contributes to the beginning of plaque and is a potential biomarker for the early identification of atherosclerosis in asymptomatic patients with diabetes.

To determine the roles of matrix metallopeptidase-9 (MMP9) on human coronary artery smooth muscle cells (HCASMCs) in vitro, early beginning of atherosclerosis in vivo in diabetic mice, and drug naïve patients with diabetes. Active human MMP9 (act-hMMP9) was added to HCASMCs and the expressions of MCP-1, ICAM-1, and VCAM-1 were measured. Act-hMMP9 (n=16) or placebo (n=15) was administered to diabetic KK.Cg-Ay/J (KK) mice. Carotid artery inflammation and atherosclerosis measurements were made at 2 and 10 weeks after treatment. An observational study of newly diagnosed drug naïve patients with type 2 diabetes mellitus (T2DM n=234) and healthy matched controls (n=41) was performed and patients had ultrasound of carotid arteries and some had coronary computed tomography angiogram for the assessment of atherosclerosis. Serum MMP9 was measured and its correlation with carotid artery or coronary artery plaques was determined. In vitro, act-hMMP9 increased gene and protein expressions of MCP-1, ICAM-1, VCAM-1, and enhanced macrophage adhesion. Exogenous act-hMMP9 increased inflammation and initiated atherosclerosis in KK mice at 2 and 10 weeks: increased vessel wall thickness, lipid accumulation, and Galectin-3+ macrophage infiltration into the carotid arteries. In newly diagnosed T2DM patients, serum MMP9 correlated with carotid artery plaque size with a possible threshold cutoff point. In addition, serum MMP9 correlated with number of mixed plaques and grade of lumen stenosis in coronary arteries of patients with drug naïve T2DM. MMP9 may contribute to the initiation of atherosclerosis and may be a potential biomarker for the early identification of atherosclerosis in patients with diabetes. https://clinicaltrials.gov, identifier NCT04424706.

EGR1 transcriptionally regulates SVEP1 to promote proliferation and migration in human coronary artery smooth muscle cells.

A low-frequency variant of sushi, von Willebrand factor type A, EGF, and pentraxin domain-containing protein 1 (SVEP1) is associated with the risk of coronary artery disease, as determined by a genome-wide association study. SVEP1 induces vascular smooth muscle cell proliferation and an inflammatory phenotype to promote atherosclerosis. In the present study, qRT‒PCR demonstrated that the mRNA expression of SVEP1 was significantly increased in atherosclerotic plaques compared to normal tissues. Bioinformatics revealed that EGR1 was a transcription factor for SVEP1. The results of the luciferase reporter assay, siRNA interference or overexpression assay, mutational analysis and ChIP confirmed that EGR1 positively regulated the transcriptional activity of SVEP1 by directly binding to its promoter. EGR1 promoted human coronary artery smooth muscle cell (HCASMC) proliferation and migration via SVEP1 in response to oxidized low-density lipoprotein (ox-LDL) treatment. Moreover, the expression level of EGR1 was increased in atherosclerotic plaques and showed a strong linear correlation with the expression of SVEP1. Our findings indicated that EGR1 binding to the promoter region drive SVEP1 transcription to promote HCASMC proliferation and migration.

Paxillin participates in the sphingosylphosphorylcholine-induced abnormal contraction of vascular smooth muscle by regulating Rho-kinase activation

BackgroundThe Ca2+-independent contraction of vascular smooth muscle is a leading cause of cardiovascular and cerebrovascular spasms. In the previous study, we demonstrated the involvement of Src family protein tyrosine kinase Fyn and Rho-kinase in the sphingosylphosphorylcholine (SPC)-induced abnormal and Ca2+-independent contraction of vascular smooth muscle, but the specific mechanism has not been completely clarified.MethodsPaxillin knockdown human coronary artery smooth muscle cells (CASMCs) and smooth muscle-specific paxillin knockout mice were generated by using paxillin shRNA and the tamoxifen-inducible Cre-LoxP system, respectively. CASMCs contraction was observed by time-lapse recording. The vessel contractility was measured by using a myography assay. Fyn, Rho-kinase, and myosin light chain activation were assessed by immunoprecipitation and western blotting. The paxillin expression and actin stress fibers were visualized by histological analysis and immunofluorescent staining.ResultsThe SPC-induced abnormal contraction was inhibited in paxillin knockdown CASMCs and arteries of paxillin knockout mice, indicating that paxillin is involved in this abnormal contraction. Further study showed that paxillin knockdown inhibited the SPC-induced Rho-kinase activation without affecting Fyn activation. In addition, paxillin knockdown significantly inhibited the SPC-induced actin stress fiber formation and myosin light chain phosphorylation. These results suggest that paxillin, as an upstream molecule of Rho-kinase, is involved in the SPC-induced abnormal contraction of vascular smooth muscle.ConclusionsThe present study demonstrated that paxillin participates in the SPC-induced abnormal vascular smooth muscle contraction by regulating Rho-kinase activation.Ak4aWCsjd4r4atTQ7PUYn2Video

Phosphoglycerate Dehydrogenase Overexpression Inhibits Ferroptosis to Repress Calcification of Human Coronary Artery Vascular Smooth Muscle Cells via the P53/SLC7A11 Pathway.

Coronary artery calcification (CAC) is in almost all patients with coronary artery disease and requires more effective therapies. We aim to explore the effects of phosphoglycerate dehydrogenase (PHGDH) on CAC. We identified the differentially expressed genes through bioinformatic analysis and selected PHGDH for further verification. Human coronary artery smooth muscle cells (HCASMCs) cultured with calcifying medium were used as models of CAC in vitro. Erastin was administered to induce ferroptosis. We determined the cell viability by the cell count kit-8 assay. The alkaline phosphatase activity, calcium content, and the expression of glutathione were evaluated by the corresponding detection kits. The calcification level was detected by alizarin red staining. Then we performed Western blot to examine the expression of runt-related transcription factor 2, bone morphogenetic protein 2, cyclooxygenase 2, glutathione peroxidase 4, P53, and solute carrier family 7a member 11 (SLC7A11). We acquired 201 differentially expressed genes and selected PHGDH to verify. In calcifying medium-induced HCASMCs, PHGDH overexpression increased the cell viability and decreased the alkaline phosphatase activity, calcium content, calcification level, and the expression of bone morphogenetic protein 2 and runt-related transcription factor 2. Additionally, we found higher levels of glutathione, glutathione peroxidase 4, and SLC7A11 and lower levels of cyclooxygenase 2 and P53 after up-regulating PHGDH. Erastin reversed the effects of PHGDH on calcification of HCASMCs. PHGDH overexpression suppresses the calcification level of HCASMCs by inhibiting ferroptosis through the P53/SLC7A11 signaling pathway, suggesting PHGDH as a promising therapeutic target of CAC.

Changes in Potassium Current and BK Channel Protein Expression in Coronary Artery Smooth Muscle Cells of Spontaneously Hypertensive Rats

Changes in Potassium Current and BK Channel Protein Expression in Coronary Artery Smooth Muscle Cells of Spontaneously Hypertensive Rats

Selenocyanate (SeCN−) acts as an efficient competitive substrate for myeloperoxidase and decreases biological damage induced by hypochlorous acid

The leukocyte-derived enzyme myeloperoxidase (MPO) is a key component of the innate immune response and mediates the killing of pathogens via the generation of the powerful oxidant hypochlorous acid (HOCl). Unintended or excessive formation of this species can however result in damage to host tissues, and this is linked with multiple pathologies associated with acute or chronic inflammation. The active (Compound I) form of MPO is promiscuous and can oxidize multiple alternative anions, in addition to the Cl− used to generate HOCl. These alternative substrates may therefore modulate MPO-mediated HOCl damage. In the current study we examined the hypothesis that selenocyanate (SeCN−), the selenium analogue of thiocyanate (SCN−, a well-established competitive MPO substrate) would inhibit HOCl-mediated damage to human plasma fibronectin (hpFN) or the extracellular matrix laid down by human coronary artery smooth muscle cells. SeCN− modulated HOCl and MPO-mediated damage, in a dose-dependent manner. These data are consistent with SeCN− acting as both a competitive substrate for Compound I of MPO (with IC50 ∼23 μM), and as a direct scavenger of HOCl. Inhibition of protein damage by SeCN− was also detected in the presence of the physiological anions Br−, I− and SCN− at the concentrations typically present in human plasma, consistent with a high affinity of SeCN− for MPO Compound I. In addition, the protective effects of SeCN− and SCN−, as competitive MPO substrates, were additive. Together these data indicate that modest concentrations of SeCN− can, like its sulfur analogue SCN−, act as an effective modulator of inflammation-induced damage.

Induced pluripotent stem cell-derived vascular smooth muscle cells as an in vitro model of coronary spastic angina

Abstract Background Coronary spastic angina (CSA), also known as Prinzmetal’s variant angina, is a form of angina caused by coronary artery spasm. CSA is characterized by enhanced basal tone of coronary artery smooth muscle and hyperreactivity to vasoconstrictor stimuli. The vascular smooth muscle hyperreactivity is likely due to a post-receptorial cellular abnormality in the regulation of myofibril contraction, suggesting the possibility of multiple stimuli acting on various cellular receptors. However, its detailed mechanism is still unclear. To investigate it, various experiments using coronary artery smooth muscle cells obtained from the CSA patients is preferable, but it is impossible to do it clinically and ethically. Purpose The purpose of this study was to establish induced pluripotent stem cell (iPSC)-derived vascular smooth muscle cells (VSMCs) and to characterize this VSMC model for CSA research. Methods Three CSA patients with ST-segment elevation, which is a characteristic of variant angina, were recruited for this study. The isolated skin fibroblasts or peripheral blood mononuclear cells were reprogrammed into iPSCs through electroporation of episomal plasmids encoding the reprogramming genes OCT3/4, SOX2, KLF4, L-MYC, LIN28, and mouse p53DD. We differentiated mesodermal using Glycogen synthase kinase 3 inhibition and Bone morphogenetic protein 4 treatment from iPSCs and resulted in the differentiation of VSMCs by platelet-derived growth factor-BB and Activin A. The differentiation of VSMCs was confirmed by VSMC-specific gene expression in qRT–PCR and fluorescence-activated cell sorting (FACS). We examined biological features and intracellular calcium response to acetylcholine (ACh) in VSMCs obtained from 3 CSA patients and 3 healthy controls. Intracellular free Ca2+ concentration ([Ca2+]i; nM) was measured by fura-2. Results CSA iPSCs were confirmed to have normal karyotypes and pluripotency to differentiate. FACS showed that VSMCs differentiated from iPSCs exhibited smooth muscle cell marker expressions including alpha-smooth muscle actin and SM22-alpha. qRT–PCR showed that VSMCs from iPSCs had expressions of ACTA2 and TAGLN gene similar to the human coronary artery smooth muscle cells. Differentiation induction rate of VSMCs differentiated from iPSCs between CSA and control did not show significant difference. [Ca2+]i at baseline did not differ significantly between them (143 nM in CSA versus 120 nM in control, p=0.63, n=3), but peak increase in [Ca2+]i from baseline after ACh stimulation was significantly increased in CSA group compared with control (372 nM versus 177 nM, p<0.05, n=3). Conclusions iPSC-derived VSMCs obtained from CSA patients showed an enhanced intracellular calcium response to ACh, which is likely responsible for CSA phenotype. Our iPSC-derived VSMC model can be useful for elucidating the mechanism of coronary spasm and developing therapeutic strategy such as drug efficacy.

Abstract 17720: The Role of Soluble Guanylyl Cyclase/NLRP3/RHOA/ROCK Axis in Coronary Artery Spasm: A Potential Biomarker and Therapeutic Target

Background: Coronary artery spasm (CAS) can lead to potentially life-threatening acute coronary syndrome. The second messenger cyclic guanosine 3',5'-monophosphate (cGMP), which is regulated by BNP-pGC-cGMP and nitric oxide (NO)-soluble guanylate cyclase (sGC)-cGMP pathways, regulate not only vasodilation but also the functions of immune cells. However, the significance of sGC, as a primary receptor for NO, is unclear in CAS. Methods: We investigated sGC and downstream signaling in patient monocyte-derived macrophages (PMDMs) and human coronary artery smooth muscle cells (HCASMCs) using computational biology and bioinformatics to correlate macrophage polarization subsets, Lp(a), and inflammasome signaling axes with CAS. Results: Plasma sGC levels were significantly higher in 30 CAS patients compared to 20 non-CAS controls (P<0.001). RNA-sequencing analysis revealed a significant association of sGC expression with NLR Family Pyrin Domain Containing (NLRP)-3 in HCASMCs and induced expression of inflammatory cytokines-specific surface markers. Lp(a) induction promoted the sGC-NLRP3 mediated lipid metabolism axis in PMDMs at both mRNA and protein levels, with elevated M1 polarization. sGC inhibition in HCASMCs reduced RhoA-GTP activity and its downstream effector ROCK, mitigating the Lp(a) effect, while sGC-specific modulator 1-H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-l-one (ODQ) treatment decreased Lp(a)-induced expression of sGC-NLRP3-inflammasome mediators and induced caspase-1, as well as subsequent cleavage of proIL-1β and proIL-18 in VSMCs. Conclusion: sGC/GC molecule in conjunction with the RHOA/ROCK pathway is an early biomarker for CAS. The sGC-NLRP3-inflammasome mediators signaling axis plays an important role in Lp(a)-regulated macrophage polarization and CAS development.