Smooth Muscle Cell Injury Research Articles

Indoxyl Sulfate Exposure inhibits Vascular Smooth Muscle Cell migration and Potentiates Vascular Injury

IntroductionChronic Kidney Disease (CKD) has been implicated in cardiovascular complications. CKD results in decreased filtration and a concomitant increase in uremic toxins. Uremic toxins are a by‐product of organic molecules, including two prominent amino acid derivatives, namely Indoxyl sulfate (IS) obtained from tryptophan and p‐Cresyl sulfate from tyrosine. Of these uremic toxins, IS has been shown to be highly potent, and implicated in exacerbation of multiple cardiovascular diseases. However, the effect of IS during vascular injury and specific contributions of Vascular Smooth Muscle Cells (VSMCs) remain unclear.MethodsTranswell migration and cell attachment assays were employed to examine the phenotypic effects of IS on VSMCs. Western blot analysis, gene silencing, and Immunofluorescence microscopy were utilized to examine the effects of IS on focal adhesion and actin related proteins.ResultsExposure of VSMCs to IS resulted in the formation of stress fibers and cytoskeletal disorganization. In the presence or absence of chemoattractants, we observed decreased migration of IS‐treated cells. Additionally, a noticeable reduction in cell area and cell attachment was evident. This led to investigation of focal adhesion, and actin‐related proteins due to their established roles in cell migration. It was determined that Focal Adhesion Kinase (FAK) and Paxillin were significantly decreased after prolonged exposure to IS. Immunofluorescence microscopy confirmed decreased FAK and Paxillin intensity at the cell periphery of IS‐treated cells. To determine whether FAK or Paxillin were the main effectors of decreased cell migration instigated by IS, gene silencing was performed. Relative to Paxillin, loss of FAK expression correlated with a reduction VSMC migration.ConclusionThese data suggest that IS contributes to alterations to focal adhesion related proteins, which in turn attenuates cell migration. IS induced loss of FAK potentiates reduced migration. Thus, IS‐induced inhibition of vascular repair may contribute to secondary complications in a subset of CVD patients.Support or Funding InformationNational Institutes of Health

Long noncoding RNA Chaer mediated Polycomb Repressor Complex 2 (PRC2) activity to promote atherosclerosis through mTOR signaling.

Recent studies highlighted long noncoding RNAs (lncRNAs) have been implicated in many biological processes and diseases. However, atherosclerosis is a major risk factor for cardiovascular disease, but the detailed mechanism of atherosclerosis progression remained unclear. In this study, we mainly focused on the role of lncRNA Chaer in atherosclerosis. RT-PCR was used to detect the expression of lncRNA Chaer in atherosclerosis patients and animal model. Moreover, the expression of Chaer in vascular smooth muscle cell dysfunction model was also measured. Proliferation ability was tested by CCK-8 and cyclin D1 assay, through loss- and gain-of-function approaches. Western-blot was used to measure the expression of H3 lysine 27 methylation, when Chaer was in different levels. RIP and ChIP assay discovered an interaction between Chaer and PRC2 through mTOR signaling. Here we identified a heart-enriched long non-coding RNA, named Cardiac Hypertrophy Associated Epigenetic Regulator (Chaer). We found that the Chaer was highly expressed in serum samples from 28 patients with atherosclerosis, compared with 28 healthy volunteers. Chaer was dramatically upregulated in atherosclerotic plaques of ApoE-/- mice. We also found that the expression of Chaer was upregulated in vascular smooth muscle cell injury model. Through loss- and gain-of-function approaches, we showed that Chaer promotes cell proliferation and induces apoptosis in vitro. Mechanistically, Chaer interacts with Polycomb Repressor Complex 2 (PRC2) through inhibiting histone H3 lysine 27 methylation. Further, this interaction is induced upon mTOR signaling pathway. According to the results, we found that lncRNA Chaer was closely related to the progression of atherosclerosis, which could be a previously uncharacterized lncRNA-dependent epigenetic checkpoint.

Paeonol protects mitochondrial injury and prevents pulmonary vascular remodeling in hypoxia

Mitochondrial injury of pulmonary artery smooth muscle cells (PASMCs) is an important stage in the development of pulmonary arterial hypertension (PAH). Recent studies revealed that Paeonol exerts anti-proliferative effects on vascular smooth muscle cells. However, whether Paeonol is directly involved in mitochondrial injury related to PAH remains unknown. Here, we found that hypoxia-induced mitochondrial injury in vivo was alleviated in the presence of Paeonol. Hypoxia mediated the mitochondrial injuries in PASMCs in vitro, including decreased ATP generation, morphological alterations, mitochondrial polarization and increased reactive oxygen species production, which were suppressed by Paeonol. Our results also indicated that the expression of peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α) was regulated by Paeonol. Paeonol caused significant alterations in mitochondrion-dependent apoptosis through PGC-1α in PASMCs. Taken together, these results provide the first evidence confirming the protective effect of Paeonol in mediating mitochondrial injury under hypoxia and elucidating the necessary role of PGC-1α in the effects of Paeonol in inducing PASMC apoptosis.

Genetic Insights Into Smooth Muscle Cell Contributions to Coronary Artery Disease.

Coronary artery disease is a complex cardiovascular disease involving an interplay of genetic and environmental influences over a lifetime. Although considerable progress has been made in understanding lifestyle risk factors, genetic factors identified from genome-wide association studies may capture additional hidden risk undetected by traditional clinical tests. These genetic discoveries have highlighted many candidate genes and pathways dysregulated in the vessel wall, including those involving smooth muscle cell phenotypic modulation and injury responses. Here, we summarize experimental evidence for a few genome-wide significant loci supporting their roles in smooth muscle cell biology and disease. We also discuss molecular quantitative trait locus mapping as a powerful discovery and fine-mapping approach applied to smooth muscle cell and coronary artery disease-relevant tissues. We emphasize the critical need for alternative genetic strategies, including cis/trans-regulatory network analysis, genome editing, and perturbations, as well as single-cell sequencing in smooth muscle cell tissues and model organisms, under both normal and disease states. By integrating multiple experimental and analytical modalities, these multidimensional datasets should improve the interpretation of coronary artery disease genome-wide association studies and molecular quantitative trait locus signals and inform candidate targets for therapeutic intervention or risk prediction.

Long-Pulse Gastric Electrical Stimulation Repairs Interstitial Cells of Cajal and Smooth Muscle Cells in the Gastric Antrum of Diabetic Rats.

Background/Aims The damage of interstitial cells of Cajal and smooth muscle cells has far-reaching implications in the pathogenesis of gastroparesis in diabetic patients. Gastric electrical stimulation (GES) is an efficient therapy for gastric motility disorders, but the mechanisms of GES require clarification. Methods Male rats were randomly divided into the control group, diabetic rat group (DM), diabetic rats with sham GES group (DM + SGES), and diabetic rats with different frequency GES group (DM + GES) (GES1: 5.5 cpm, 100 ms, 4 mA; GES2: 5.5 cpm, 300 ms, 4 mA; and GES3: 5.5 cpm, 550 ms, 2 mA). Gastric contractions were explored using the organ bath technique. The alterations of interstitial cells of Cajal, the SCF/c-kit pathway, and smooth muscle cells were also investigated. Results (1) Gastric contractions were significantly improved in the DM + GES group compared with those in the DM group. (2) The damage of interstitial cells of Cajal was prevented in the DM + GES group in contrast to the DM group. Moreover, long-pulse GES increased the expression of the SCF/c-kit pathway. More proliferated interstitial cells of Cajal in muscle layers were observed obviously in the DM + GES group. (3) The number of smooth muscle cells in the DM group was not significantly decreased compared with that in the control group. However, ultrastructural changes were distinctly damaged in the DM group. The application of GES protected against the alteration of the ultrastructures of smooth muscle cells. Conclusions Long-pulse GES improves gastric contraction possibly by enhancing the proliferation of interstitial cells of Cajal and restoring the injury of smooth muscle cells.

LncRNA TUG1 promotes proliferation of vascular smooth muscle cell and atherosclerosis through regulating miRNA-21/PTEN axis.

Atherosclerosis is a major risk factor for cardiovascular disease, but its mechanism of progression remained unclear. However, many long non-coding RNAs (lncRNAs) have recently been implicated in different processes for cardiovascular disease. In this study, we mainly focused on the role of lncRNA TUG1 in atherosclerosis. qRT-PCR was used to detect the expression of lncRNA TUG1 in atherosclerosis patients and animal model. Moreover, the expression of TUG1 in vascular smooth muscle cell dysfunction model was also measured. Proliferation ability was tested by CCK-8 and cyclin D1 assay, through loss- and gain-of function approaches. Western-blot was used to measure the expression of PTEN, when TUG1 was in different levels. We found that the lncRNA TUG1 was highly expressed in serum samples from 38 patients with atherosclerosis, compared with 24 healthy volunteers. LncRNA TUG1 was dramatically upregulated in atherosclerotic plaques of ApoE-/- mice. We also found that the expression of TUG1 was upregulated in vascular smooth muscle cell injury model. Through loss- and gain-of function approaches, we showed that TUG1 promotes cell proliferation and induces apoptosis in vitro. What's more, TUG1 expression level was reversely correlated with PTEN expression in patients with atherosclerosis. LncRNA TUG1 could compete with PTEN for miR-21 binding. We found that lncRNA TUG1 was closely related to the progression of atherosclerosis, which could be a potential target for treating atherosclerosis.

Tetramethylpyrazine protects against high glucose-induced vascular smooth muscle cell injury through inhibiting the phosphorylation of JNK, p38MAPK, and ERK.

ObjectivesHigh glucose-induced alterations in vascular smooth muscle cell behavior have not been fully characterized. We explored the protective mechanism of tetramethylpyrazine (TMP) on rat smooth muscle cell injury induced by high glucose via the mitogen-activated protein kinase (MAPK) signaling pathway.MethodsVascular smooth muscle cells (VSMCs) isolated from rat thoracic aortas were divided into control, high glucose (HG), and pre-hatching TMP groups. The effect of different glucose concentrations on cell viability and on the migration activity of VSMC cells was examined using MTT analysis and the wound scratch assay, respectively. Superoxide dismutase (SOD) and malondialdehyde (MDA) levels were measured using enzyme-linked immunoassays. The levels of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38MAPK, and MAPK phosphorylation were assessed by western blotting.ResultsCell proliferation was remarkably increased by increased glucose concentrations. Compared with the HG group, the migratory ability of VSMC cells was reduced in the presence of TMP. TMP also decreased the MDA content in the supernatant, but significantly increased the SOD activity. Western blotting showed that TMP inhibited the phosphorylation of JNK, p38MAPK, and ERK.ConclusionsTMP appears to protect against HG-induced VSMC injury through inhibiting reactive oxygen species overproduction, and p38MAPK/JNK/ERK phosphorylation.

Abstract 113: Thoracic Aortic Aneurysms Associated With Bicuspid Aortic Valve Have Altered MicroRNA Expression

Bicuspid aortic valve (BAV) is the most common congenital heart malformation, affecting 1-2% of the population. BAV is caused by fusion of two of the three aortic valve leaflets in the heart during foetal development. Progressive dilatation of the thoracic aorta, resulting in aneurysm (TAA), develops in approximately 50% of individuals with BAV, and can be fatal. The cause of BAV-TAA is undetermined, however, current understanding suggests that it is a complex interplay between genetic susceptibility and the abnormal haemodynamic stress generated by the malformed valve. Changes in the expression of post-transcriptional genetic modifiers, such as microRNA (miRNA), can alter protein expression and disrupt normal tissue function, contributing to disease. miRNA are also viable therapeutic targets with demonstrated success in disease treatment. We hypothesised that there is altered expression of miRNA in BAV-TAA tissue that contributes to TAA development. Total RNA was isolated from aortic tissue of 11 patients with BAV-TAA (Age 54 ± 12 years; M:F 10:1), and 6 normal controls with no aortic disease (Age 35 ± 18 years; M:F 4:2). RNA was reverse transcribed with primers for 818 different miRNA and qPCR was performed using Taqman® OpenArray® Human miRNA Panels. A significant difference in miRNA expression was defined as a >±2 fold change (p<0.05) compared to control. In BAV-TAA tissue, miR-214, miR-497, miR-22, miR-151-3p and miR-24 were significantly decreased. These miRNA have been previously implicated in the regulation of biological pathways relevant to BAV-TAA, including vascular smooth muscle cell (VSMC) injury and apoptosis, oxidative and shear stress, vascular relaxation, VSMC phenotype and TGF-beta signalling. Therefore, these miRNA may contribute to BAV-TAA pathogenesis, either as part of a compromised genetic background, or in relation to haemodynamic stress arising from BAV. This study has identified a novel expression profile of miRNA in BAV-TAA, and provides promising candidates for further exploration and treatment.

KDM3A inhibition attenuates high concentration insulin‑induced vascular smooth muscle cell injury by suppressing MAPK/NF‑κB pathways.

Previous studies have indicated that lysine (K)-specific demethylase 3A (KDM3A) is associated with diverse diabetes-associated cardiovascular complications in response to high glucose levels. However, the effects of KDM3A on the pathological progression of cardiovascular injuries in response to high insulin levels remain unknown. The present study aimed to explore whether KDM3A knockdown may attenuate high insulin-induced vascular smooth muscle cell (VSMC) dysfunction, and to further investigate the underlying mechanisms. Primary VSMCs were isolated from the thoracic aorta of Sprague-Dawley rats. Lentiviral vectors encoding control-small interfering (si)RNA or KDM3A-siRNA were transduced into VSMCs for 72 h, and cells were subsequently incubated in medium containing 100 nM insulin for a further 5 days. Cellular proli feration, migration and apoptosis were measured by Cell Counting kit-8, Transwell chamber assay and flow cytometry, respectively. Reactive oxygen species (ROS) were detected using the dihydroethidium fluorescent probe. The mRNA expression levels of interleukin-6 and monocyte chemotactic protein-1 were measured by reverse transcription-quantitative polymerase chain reaction. Furthermore, the protein expression levels of KDM3A, mitogen-activated protein kinases (MAPKs), nuclear factor (NF)-κB/p65, B-cell lymphoma 2 (Bcl-2)-associated X protein and Bcl-2 were evaluated by western blotting. Lentivirus transduction with KDM3A-siRNA markedly reduced the elevated expression of KDM3A induced by high insulin stimulation in VSMCs. In addition, inhibition of KDM3A significantly ameliorated insulin-induced VSMC proliferation and migration, which was accompanied by decreased ROS levels, cell apoptosis and inflammatory cytokine levels. Furthermore, KDM3A gene silencing mitigated phosphorylation of MAPKs and NF-κB/p65 activation. In conclusion, KDM3A inhibition may exert numerous protective effects on high insulin-stimulated VSMCs, and the underlying mechanisms may be partly associated with inactivation of MAPK/NF-κB signaling pathways.

Salidroside attenuates hypoxia/reoxygenation-induced human brain vascular smooth muscle cell injury by activating the SIRT1/FOXO3α pathway.

It has been reported that salidroside (SAL), a natural dietary isothiocyanate, exhibits neuroprotective roles in cerebral ischemia-reperfusion injury. However, to the best of our knowledge, its underlying protective mechanism remains unknown. Sirtuin 1 (SIRT1) is a class III histone deacetylase involved in a variety of cellular functions. SIRT1 has been identified as a mediator of cerebral ischemia and may induce neuroprotection by activating various intracellular downstream targets, such as forkhead box protein O3α (FOXO3α). Therefore, the present study aimed to investigate whether SAL protects human brain vascular smooth muscle cells (HBVSMC) against hypoxia/reoxygenation (H/R) injury, which is a cell model of cerebral ischemia-reperfusion injury, through regulating the SIRT1-activited signaling pathway. The present study revealed that H/R treatment significantly reduced the expression of SIRT1 protein in HBVSMCs. Additionally, pretreatment with SAL reversed the H/R-induced decrease in cellular viability, increased caspase-3 activity, the appearance of apoptotic cells and the apoptosis rate in HBVSMCs. SAL attenuated the H/R-induced decrease in the expression of SIRT1 and phosphorylated FOXO3α protein in HBVSMCs, suggesting that the protective role of SAL in H/R injury occurs via the SIRT1/FOXO3α pathway. Furthermore, sirtinol, a SIRT1-specific inhibitor, suppressed the inhibitory effects of SAL on H/R-induced cytotoxicity and apoptosis as indicated by the downregulation of cell viability and upregulation of caspase-3 activity and apoptosis rate induced by sirtinol treatment in HBVSMCs. The reversal effects of SAL on H/R-induced alternation of B-cell lymphoma (Bcl-2) and Bcl-2 associated X protein expression were also attenuated by sirtinol. These results suggest that SAL exhibits neuroprotective effects against H/R injury by activating the SIRT1/FOXO3α pathway, which may become a novel potential therapeutic target for the treatment of cerebral ischemic disease.

The Protective Effect of DL0805 Derivatives on Pulmonary Artery Cells and the Underlying Mechanisms Study.

Pulmonary hypertension (PH) is a severe disease characterized by a progressive increase in pulmonary vascular resistance, initially due to abnormal pulmonary vasoconstriction in response to endothelial and smooth muscle cells injury. The discovery of new chemical entities having a protective effect on pulmonary artery cells could be meaningful for the treatment of PH. We evaluated the protective effect of DL0805 derivatives (DL0805-1 and DL0805-2) on pulmonary artery vascular cells, including human pulmonary artery endothelial cells (HPAECs) and human pulmonary artery smooth muscle cells (HPASMCs). DL0805 derivatives are novel ROCKs (Rho-associated coiled-coil forming protein serine/threonine kinases) inhibitors. Treatment of HPAECs with DL0805-2 (10 μM) cultured under a hypoxic environment could significantly reduce the proliferation of cells. Meanwhile, the compounds inhibited the production of reactive oxygen species (ROS) in HPAECs at every dose tested. A Western Blot experiment showed that the protective effect of DL0805 derivatives might result from the down-regulation of RhoA (Ras homolog gene family, member A) expression and the inhibition of ROCKs activity. In addition, the compounds inhibited the proliferation of HPASMCs induced by fetal bovine serum (FBS) or platelet derived growth factor BB (PDGF-BB), and suppressed the F-actin remodeling induced by endothelin. The preliminary results from an immunofluorescence assay showed that DL0805 derivatives inhibited the activity of ROCKs in HPASMCs. The above mentioned results indicated that DL0805 derivatives have a protective effect on pulmonary artery cells, and the underlying mechanisms might be the result of inhibition of RhoA/ROCK signaling pathway.

TRPM8 downregulation by angiotensin II in vascular smooth muscle cells is involved in hypertension.

Angiotensin II (AngII)-induced injury of vascular smooth muscle cells (VSMCs) serves an important role in hypertension and other cardiovascular disorders. Transient receptor potential melastatin8 (TRPM8) is a thermally‑regulated Ca2+‑permeable channel that is activated by reduced body temperature. Although several recent studies have revealed the regulatory effect of TRPM8 in vascular tone and hypertension, the precise role of TRPM8 in dysfunction of vascular smooth muscle cells (VSMCs) induced by AngII remains elusive. In the present study, the possible function of TRPM8 in AngII‑induced VSMCs malfunction invivo and invitro was investigated. In the aortae from rats that had undergone a two‑kidney one‑clip operation, which is a widely‑used renovascular hypertension model, the mRNA and protein levels of TRPM8 were reduced. In addition, exogenous AngII treatment decreased TRPM8 mRNA and protein expression levels in primary cultures of rat VSMCs. TRPM8 activation by menthol, a pharmacological agonist, in VSMCs, significantly attenuated the AngII‑induced increase in reactive oxygen species and H2O2 production. In addition, TRPM8 activation reduced the AngII‑induced upregulation of NADPH oxidase (NOX)1 and NOX4 in VSMCs. Furthermore, TRPM8 activation relieved the AngII‑induced activation of ras homolog gene family, member A‑rho associated protein kinase2 and janus kinase2 signaling pathways in VSMCs. In conclusion, the results presented in the current study indicated that TRPM8 downregulation by AngII in VSMCs may be involved in hypertension.

Human leukocyte antigen G single-nucleotide polymorphism -201 (CC–CC) donor–recipient genotype matching as a predictor of severe cardiac allograft vasculopathy

In heart transplant recipients, human leukocyte antigen G (HLA-G) has been shown to inhibit endothelial and smooth muscle cells injury in vitro, suggesting protection against cardiac allograft vasculopathy (CAV). Although the expression of HLA-G is regulated by single-nucleotide polymorphisms (SNPs), their association with CAV remains unknown. Therefore, the objective of this study was to determine the association between recipient and donor HLA-G SNPs with CAV. We retrospectively analyzed DNA for HLA-G SNPs of 251 adult heart recipients, 196 of whom had their corresponding donors included. Severe CAV was defined as ISHLT Category 2 or 3. The association between donor-recipient genotypes and diagnosis of severe CAV over time was evaluated with parametric hazard regression models. Recipient age was 48 ± 12 years, whereas donor age was 35 ± 14 years. Median follow-up was 5.0 years (range 1 day to 13.2 years). At 10 years after transplantation, freedom from severe CAV, retransplantation or death was 64%. In multivariable analysis adjusted for donor age, recipient weight and pre-transplant Class II antibodies, the presence of donor-recipient SNP -201 (CC-CC) matching was associated with an increased risk of severe CAV (hazard ratio 11.9; 95% confidence interval 4.3 to 32.9; p < 0.001). Matching of donor-recipient SNP -201 (CC-CC) was an independent risk factor for the diagnosis of severe CAV. HLA-G SNP genotypes may reveal a pathogenic pathway to be explored for diagnostic and therapeutic strategies for CAV.

Biodegradable Elastomers with Antioxidant and Retinoid-like Properties.

Intimal hyperplasia (IH) is a type of scarring that involves complex pathophysiological responses of the vasculature to injury, including overproliferation and migration of vascular smooth muscle cells (VSMCs), adventitial fibroblasts, and the activation of macrophages. The objective of this research was to develop a biodegradable polymer with intrinsic properties that would combat the cellular processes that contribute to IH. Citric acid, 1,8-octanediol, and all-trans retinoic acid (atRA) were incorporated into a polyester network via a condensation reaction to form the thermoset poly(1,8-octamethylene-citrate-co-retinate) (POCR). POCR was chemically characterized and assessed for the presence of antioxidant and retinoidlike properties. HNMR and ATR-FTIR confirmed the incorporation of atRA into the backbone of the polymer network. POCR was able to scavenge radicals and inhibit lipid peroxidation. The proliferation and migration of vascular smooth muscle cells cultured on POCR were inhibited, whereas endothelial cell proliferation and migration were not. These results are consistent with the biological effects of atRA. These results are the first to demonstrate the synthesis of a polymer with intrinsic antirestenotic properties for potential use in the fabrication of vascular devices such as stents and vascular grafts.

Pathogenesis of focal cytoplasmic necrosis of the smooth muscle cells in hypertensive rat arterial media.

Hypertensive rat arteries exhibited severe medial smooth muscle cell injury and necrosis. Electron microscopic observations showed the smooth muscle cells of these arteries exhibited characteristics of focal cytoplasmic necrosis forming new cytodemarcating membrane between the healthy cytoplasm and necrotic cytoplasm. When the focal necrotic cytoplasm disappeared from the injured smooth muscle cells, it left it with a moth-eaten leaf-like appearance (moth-eaten necrosis). At an advanced stage of injury, smooth muscle cells changed to islet-like cell bodies with newly formed basement membranes around them, and further islet-like cell bodies and cell debris disappeared leaving lamellar and reticular basement membranes.In hypertensive rats injected with nitroblue tetrazolium (NBT), formazan deposits were observed in the medial cells and nitrotyrosine, a biomarker of peroxynitrite, were immunohistochemically observed in the arterial media. Nick-end positive extranuclear small granular bodies, which might have derived from focal necrotic cytoplasm and nucleus, were detected in the arterial media using DNA nick-end labeling method. Based on electron microscopical and histochemical findings, we conjectured that the focal cytoplasmic necrosis of the smooth muscle cells in the arterial media depended on injury arising from mitochondria-derived oxidants.

Protective effect of the ultra-filtration extract from Xin Mai Jia on human aortic smooth muscle cell injury induced by hydrogen peroxide

The aim of the present study was to explore whether an ultra-filtration extract from Xin Mai Jia (XMJ), a Chinese medicinal formulation, has a protective effect on human aortic smooth muscle cell (HASMC) injury models induced by hydrogen peroxide (H2O2), and to consider the mechanism and efficacy of the therapeutic action of XMJ on atherosclerosis. HASMCs were injured by H2O2 and then exposed to various concentrations of XMJ. The morphological changes, growth, proliferation, migration and cytokine release of HASMCs were detected using 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), an enzyme-linked immunosorbent assay and a scratch adhesion test. H2O2 significantly promoted the proliferation of HASMCs. The ultra-filtration extract from XMJ was observed to significantly attenuate the morphological changes of injured HASMCs, reduce the expression levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), interleukin (IL)-1, IL-6 and nuclear factor (NF)-κB, and increase the expression levels of matrix metalloproteinase (MMP)-2 and tissue inhibitor of metalloproteinase (TIMP). XMJ has clear anti-inflammatory and antioxidant effects, and significantly inhibits the proliferation and migration of HASMCs.

GW24-e3847 Nrf2 activation attenuates oxidative stress-induced injury of vascular smooth muscle cells

ObjectivesTo investigate the role of Nuclear factor-erythroid 2-related factor 2 (Nrf2) activation on rat vascular smooth muscle cells ress.MethodsRat aortic VSMCs were cultured and divided into control group, oxidative damage...

Platelet factor 4 mediates vascular smooth muscle cell injury responses

AbstractActivated platelets release many inflammatory molecules with important roles in accelerating vascular inflammation. Much is known about platelet and platelet-derived mediator interactions with endothelial cells and leukocytes, but few studies have examined the effects of platelets on components of the vascular wall. Vascular smooth muscle cells (VSMCs) undergo phenotypic changes in response to injury including the production of inflammatory molecules, cell proliferation, cell migration, and a decline in the expression of differentiation markers. In this study, we demonstrate that the platelet-derived chemokine platelet factor 4 (PF4/CXCL4) stimulates VSMC injury responses both in vitro and in vivo in a mouse carotid ligation model. PF4 drives a VSMC inflammatory phenotype including a decline in differentiation markers, increased cytokine production, and cell proliferation. We also demonstrate that PF4 effects are mediated, in part, through increased expression of the transcription factor Krüppel-like factor 4. Our data indicate an important mechanistic role for platelets and PF4 in VSMC injury responses both in vitro and in vivo.

Low-Flow Motion in the Vascular Ocean

Much like the ebb and tide of the seas, most physiologic functions are observed to operate in balance; a constant yin and yang of biology operates to maintain the body in careful equilibrium, yet the realm of vascular biology has focused mostly on the ability of vessels to dilate in an effort to improve the supply of flow to demanding tissues. It is only fitting and appropriately balanced that new data now support the concept of the endothelium and vascular wall directing constriction to low-flow territories. Moreover, we just might be able to harness the ability of vessels to appropriately constrict as a measure of endothelial health. Despite the fact that the notion of low-flow mediated constriction (L-FMC) has been intermittently studied over the past decades,1,2 and recently been reprised in the cardiac literature,3 relatively little is known regarding the mechanisms behind this phenomenon, let alone their potential clinical implications. In this issue of Circulation: Cardiovascular Interventions , Dawson et al4 present new data showing that vascular injury—potentially secondary to denudation of the endothelium or smooth-muscle cell injury—following a radial access approach impairs both endothelial-dependent dilation and L-FMC, and moreover, that this can be ameliorated with subsequent isometric handgrip exercise training. This complex study design and provocative set of results not only implicates a potential mechanism for L-FMC, but also provides a relatively safe and easy treatment for an increasingly common complication seen in interventional practice. Article see p 713 The present study by Dawson et al essentially combines 2 separate experiments to effectively underscore the importance of the endothelium in L-FMC. The first experiment follows 32 patients immediately before a radial approach to percutaneous coronary intervention and then 1 day after, to measure vascular reactivity to reactive hyperemia in both the catheterized arm and …

Remodeling of the Muscle Layer (Detrusor Muscle) of Hyperactive Bladder Disease in Patients with Benign Prostatic Hyperplasia

We studied remodeling of the detrusor of hyperactive bladder in patients with benign prostatic hyperplasia. Detrusor remodeling was caused by degenerative and atrophic changes and elimination of smooth muscle cells, compensatory hypertrophy of remaining cells, and diffuse or focal-diffuse replacement fibrosis. Focal or diffuse infiltration of all layers of the detrusor with lymphocytes and plasma cells is an important pathologic feature of hyperactive bladder. These changes correlated with pronounced remodeling of the glandular and fibrotic-muscular layers in the prostate gland. We have identified stereotyped patterns of the intracellular reorganization of smooth muscle cells in the detrusor of hyperactive bladder and in the prostate with benign prostatic hyperplasia, which represent both the compensatory and adaptive reactions (hypertrophied cells with minor ultrastructural changes) and the types of smooth muscle cell injury ("dark" electron-dense cells and "light" cells with pronounced lysis of myofilaments and discomplexation of organelles).