The Role of Vascular Smooth Muscle Cells in Arterial Remodeling: Focus on Calcification-Related Processes

Hydrogen Sulfide and Oxygen Homeostasis in Atherosclerosis: A Systematic Review from Molecular Biology to Therapeutic Perspectives

Atherosclerosis is a complex pathological condition marked by the accumulation of lipids in the arterial wall, leading to the development of plaques that can eventually rupture and cause thrombotic events. In recent years, hydrogen sulfide (H₂S) has emerged as a key mediator of cardiovascular homeostasis, with potential therapeutic applications in atherosclerosis. This systematic review highlights the importance of understanding the complex interplay between H₂S, oxygen homeostasis, and atherosclerosis and suggests that targeting H₂S signaling pathways may offer new avenues for treating and preventing this condition. Oxygen homeostasis is a critical aspect of cardiovascular health, and disruption of this balance can contribute to the development and progression of atherosclerosis. Recent studies have demonstrated that H₂S plays an important role in maintaining oxygen homeostasis by regulating the function of oxygen-sensing enzymes and transcription factors in vascular cells. H₂S has been shown to modulate endothelial nitric oxide synthase (eNOS) activity, which plays a key role in regulating vascular tone and oxygen delivery to tissues. The comprehensive analysis of the current understanding of H₂S in atherosclerosis can pave the way for future research and the development of new therapeutic strategies for this debilitating condition. PROSPERO ID: 417150.

Inhibition of p90RSK Ameliorates PDGF-BB-Mediated Phenotypic Change of Vascular Smooth Muscle Cell and Subsequent Hyperplasia of Neointima

Platelet-derived growth factor type BB (PDGF-BB) regulates vascular smooth muscle cell (VSMC) migration and proliferation, which play critical roles in the development of vascular conditions. p90 ribosomal S6 kinase (p90RSK) can regulate various cellular processes through many different target substrates in several cell types, but the regulatory function of p90RSK on PDGF-BB-mediated cell migration and proliferation and subsequent vascular neointima formation has not yet been extensively examined. In this study, we investigated whether p90RSK inhibition protects VSMCs against PDGF-BB-induced cellular phenotypic changes and the molecular mechanisms underlying the effect of p90RSK inhibition on neointimal hyperplasia in vivo. Pretreatment of cultured primary rat VSMCs with FMK or BI-D1870, which are specific inhibitors of p90RSK, suppressed PDGF-BB-induced phenotypic changes, including migration, proliferation, and extracellular matrix accumulation, in VSMCs. Additionally, FMK and BI-D1870 repressed the PDGF-BB-induced upregulation of cyclin D1 and cyclin-dependent kinase-4 expression. Furthermore, p90RSK inhibition hindered the inhibitory effect of PDGF-BB on Cdk inhibitor p27 expression, indicating that p90RSK may induce VSMC proliferation by regulating the G0/G1 phase. Notably, treatment with FMK resulted in attenuation of neointima development in ligated carotid arteries in mice. The findings imply that p90RSK inhibition mitigates the phenotypic switch and neointimal hyperplasia induced by PDGF-BB.

Melatonin and TGF-β-Mediated Release of Extracellular Vesicles

The immune system, unlike other systems, must be flexible and able to "adapt" to fully cope with lurking dangers. The transition from intracorporeal balance to homeostasis disruption is associated with activation of inflammatory signaling pathways, which causes modulation of the immunology response. Chemotactic cytokines, signaling molecules, and extracellular vesicles act as critical mediators of inflammation and participate in intercellular communication, conditioning the immune system's proper response. Among the well-known cytokines allowing for the development and proper functioning of the immune system by mediating cell survival and cell-death-inducing signaling, the tumor necrosis factor α (TNF-α) and transforming growth factor β (TGF-β) are noteworthy. The high bloodstream concentration of those pleiotropic cytokines can be characterized by anti- and pro-inflammatory activity, considering the powerful anti-inflammatory and anti-oxidative stress capabilities of TGF-β known from the literature. Together with the chemokines, the immune system response is also influenced by biologically active chemicals, such as melatonin. The enhanced cellular communication shows the relationship between the TGF-β signaling pathway and the extracellular vesicles (EVs) secreted under the influence of melatonin. This review outlines the findings on melatonin activity on TGF-β-dependent inflammatory response regulation in cell-to-cell communication leading to secretion of the different EV populations.

Vascular Biology of arterial aneurysms

OBJECTIVE

This review aims to analyze biomolecular and cellular events responsible for arterial aneurysm formation with particular attention to vascular remodeling that determines the initiation and the progression of arterial aneurysm, till rupture.

METHODS

This review was conducted searching libraries such as Web of Science, Scopus, ScienceDirect and Medline. Used keywords with various combinations were: "arterial aneurysms", "biology", "genetics", "proteomics", "molecular", "pathophysiology" and extracellular matrix" RESULTS: There are several genetic alterations responsible of syndromic and non-syndromic disease that predispose to aneurysm formation. ECM imbalance, mainly due to the alteration of vascular smooth muscle cells (VSMCs) homeostasis, overexpression of metalloproteinases (MPs) and cytokines activation, determines weakness of the arterial wall that dilates thus causing aneurysmal disease. Altered mechanotransduction in the ECM may also trigger and sustain anomalous cellular and biochemical signaling. Different cell population such as VSMCs, macrophages, perivascular adipose tissue (PVAT) cells, vascular wall resident stem cells (VWRSCs) are all involved at different levels CONCLUSIONS: Improving knowledge in vascular biology may help researchers and physicians in better targeting aneurysmal disease in order to better prevent and better treat such important disease.

Accelerated Vascular Aging in Chronic Kidney Disease: The Potential for Novel Therapies

The pathophysiology of vascular disease is linked to accelerated biological aging and a combination of genetic, lifestyle, biological, and environmental risk factors. Within the scenario of uncontrolled artery wall aging processes, CKD (chronic kidney disease) stands out as a valid model for detailed structural, functional, and molecular studies of this process. The cardiorenal syndrome relates to the detrimental bidirectional interplay between the kidney and the cardiovascular system. In addition to established risk factors, this group of patients is subjected to a plethora of other emerging vascular risk factors, such as inflammation, oxidative stress, mitochondrial dysfunction, vitamin K deficiency, cellular senescence, somatic mutations, epigenetic modifications, and increased apoptosis. A better understanding of the molecular mechanisms through which the uremic milieu triggers and maintains early vascular aging processes, has provided important new clues on inflammatory pathways and emerging risk factors alike, and to the altered behavior of cells in the arterial wall. Advances in the understanding of the biology of uremic early vascular aging opens avenues to novel pharmacological and nutritional therapeutic interventions. Such strategies hold promise to improve future prevention and treatment of early vascular aging not only in CKD but also in the elderly general population.

Chitinase-3 like-protein-1, matrix metalloproteinase -9 and positive intracranial arterial remodelling

Introduction

Positive intracranial arterial remodelling is a dilated lesion of the large intracranial vessels; however, its pathogenesis is currently unknown. Some studies have identified chitinase-3 like-protein-1 (YKL-40) and matrix metalloproteinase (MMP)-9 as circulating inflammatory factors involved in positive vascular remodelling. Herein, we aimed to investigate the relationship between changes in serum YKL-40 and MMP-9 levels and positive intracranial arterial remodelling in patients with cerebral small vessel disease (CSVD).

Methods

A total of 110 patients with CSVD were selected. Patients with brain arterial remodelling (BAR) scores >1 times the standard deviation were defined as the positive intracranial artery remodelling group (n = 21 cases), and those with BAR scores ≤1 times the standard deviation were defined as the non-positive intracranial artery remodelling group (n = 89 cases). Serum YKL-40 and MMP-9 levels were measured using an enzyme-linked immunosorbent assay kit. Factors influencing positive intracranial artery remodelling using binary logistic regression analysis and predictive value of YKL-40 and MMP-9 for positive intracranial arterial remodelling in patients with CSVD were assessed by a subject receiver operating characteristic curve.

Results

Statistically significant differences in serum YKL-40 and MMP-9 levels were observed between the positive and non-positive remodelling groups (p < 0.05). The integrated indicator (OR = 9.410, 95% CI: 3.156 ~ 28.054, P<0.01) of YKL-40 and MMP-9 levels were independent risk factors for positive intracranial arterial remodelling. The integrated indicator (OR = 3.763, 95% CI: 1.884 ~ 7.517, p < 0.01) of YKL-40 and MMP-9 were independent risk factors for positive arterial remodelling in posterior circulation, but were not significantly associated with positive arterial remodelling in anterior circulation (p > 0.05). The area under the curve for YKL-40 and MMP-9 diagnostic positive remodelling was 0.778 (95% CI: 0.692–0.865, p < 0.01) and 0.736 (95% CI: 0.636–0.837, p < 0.01), respectively.

Discussion

Elevated serum YKL-40 and MMP-9 levels are independent risk factors for positive intracranial arterial remodelling in patients with CSVD and may predict the presence of positive intracranial arterial remodelling, providing new ideas for the mechanism of its occurrence and development and the direction of treatment.

Cell Therapy: A New Technology for Cerebral Circulation Restoration after Ischemia/Reperfusion

Cell therapy with mesenchymal stem cells (MSCs) may be a promising technique for cerebral blood flow restoration after transient ischemia. Before a practical application of the cell material, 7-9 days are required for its cultivation. We studied the efficacy of human MSC (hMSC) transplantation performed 7 days after cerebral ischemia/reperfusion (I/R) to help recover cerebral circulation. The intravital micrograph technique was used to comparatively evaluate the vasculature density in the pia mater and the reactivity of the pial arteries in response to acetylcholine (ACh) in rats after I/R (clamping of both carotid arteries and a simultaneous decrease in and strict maintenance of the mean BP at 45 ± 2 mm Hg for 12 min) and with/without hMSC transplantation. Perfusion (P) in the sensorimotor cortex was assessed using laser dopplerography. After 14 and 21 days, the vasculature density in I/R-affected rats was 1.2- to 1.4-fold and 1.2- to 1.3-fold lower, respectively, than that in the controls. The number of ACh-dilated arteries decreased 1.6- to 1.9-fold and 1.2- to 1.7-fold 14 and 21 days after I/R, respectively. After 21 days, the P level decreased 1.6-fold, on average. Administration of hMSCs on day 7 after I/R resulted in complete recovery of the vasculature density by day 14. ACh-mediated dilatation fully recovered only in arteries of less than 40 μm in diameter within 21 days. After 21 days, the P level was 1.2-fold lower than that in the controls but significantly higher than that in rats after I/R without hMSCs. Delayed administration of MSCs after a transient cerebral ischemic attack affords the time for the procedures required to prepare cell material for transplantation and provides a good therapeutic response in the pial microvasculature.

Atherosclerosis Calcification: Focus on Lipoproteins

Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipids in the vessel wall, leading to the formation of an atheroma and eventually to the development of vascular calcification (VC). Lipoproteins play a central role in the development of atherosclerosis and VC. Both low- and very low-density lipoproteins (LDL and VLDL) and lipoprotein (a) (Lp(a)) stimulate, while high-density lipoproteins (HDL) reduce VC. Apolipoproteins, the protein component of lipoproteins, influence the development of VC in multiple ways. Apolipoprotein AI (apoAI), the main protein component of HDL, has anti-calcific properties, while apoB and apoCIII, the main protein components of LDL and VLDL, respectively, promote VC. The role of lipoproteins in VC is also related to their metabolism and modifications. Oxidized LDL (OxLDL) are more pro-calcific than native LDL. Oxidation also converts HDL from anti- to pro-calcific. Additionally, enzymes such as autotaxin (ATX) and proprotein convertase subtilisin/kexin type 9 (PCSK9), involved in lipoprotein metabolism, have a stimulatory role in VC. In summary, a better understanding of the mechanisms by which lipoproteins and apolipoproteins contribute to VC will be crucial in the development of effective preventive and therapeutic strategies for VC and its associated cardiovascular disease.

Aortic Stiffness: A Major Risk Factor for Multimorbidity in the Elderly

Multimorbidity, the coexistence of multiple health conditions in an individual, has emerged as one of the greatest challenges facing health services, and this crisis is partly driven by the aging population. Aging is associated with increased aortic stiffness (AoStiff), which in turn is linked with several morbidities frequently affecting and having disastrous consequences for the elderly. These include hypertension, ischemic heart disease, heart failure, atrial fibrillation, chronic kidney disease, anemia, ischemic stroke, and dementia. Two or more of these disorders (multimorbidity) often coexist in the same elderly patient and the specific multimorbidity pattern depends on several factors including sex, ethnicity, common morbidity routes, morbidity interactions, and genomics. Regular exercise, salt restriction, statins in patients at high atherosclerotic risk, and stringent blood pressure control are interventions that delay progression of AoStiff and most likely decrease multimorbidity in the elderly.

Basal ganglia calcifications: No association with cognitive function

BACKGROUND AND PURPOSE

Basal ganglia calcifications (BGC), a form of vascular calcification, are a common brain computed tomography (CT) finding. We investigated whether BGC are associated with cognitive function and examined the association between vascular risk factors and BGC.

MATERIAL AND METHODS

Patients who visited a memory clinic of a Dutch general hospital between April 2009 and April 2015 were included. The patients underwent a standard diagnostic work up including cognitive tests (Cambridge Cognitive Examination, including the Mini Mental State Examination) and brain CT. Vascular risk factors such as hypertension, diabetes mellitus, hyperlipidemia and smoking were assessed. CTs were analyzed for presence and severity (absent, mild, moderate or severe) of BGC. Multivariable logistic regression was used to identify risk factors for BGC and linear regression for the association between BGC and cognitive function.

RESULTS

Of the 1992 patients, 40.3% was male. The median age was 80 years and 866 patients (43.5%) had BGC. BGC was associated with female gender (odds ratio (OR) 1.27, 95% confidence interval (CI) 1.06-1.53, p 0.011), and inversely associated with hypertension (OR 0.74, 95% CI 0.60-0.89, p 0.002) and use of antihypertensive drugs (OR 0.79, 95% CI 0.64-0.98, p 0.031). No association was found between presence and severity of BGC and cognitive function or other vascular risk factors.

CONCLUSIONS

No association with cognitive function was found. Risk factors for BGC were female gender, while hypertension and antihypertensive drug use were associated with a lower risk of BGC.

Mitochondrial dynamics in vascular remodeling and target-organ damage

Vascular remodeling is the pathological basis for the development of many cardiovascular diseases. The mechanisms underlying endothelial cell dysfunction, smooth muscle cell phenotypic switching, fibroblast activation, and inflammatory macrophage differentiation during vascular remodeling remain elusive. Mitochondria are highly dynamic organelles. Recent studies showed that mitochondrial fusion and fission play crucial roles in vascular remodeling and that the delicate balance of fusion-fission may be more important than individual processes. In addition, vascular remodeling may also lead to target-organ damage by interfering with the blood supply to major body organs such as the heart, brain, and kidney. The protective effect of mitochondrial dynamics modulators on target-organs has been demonstrated in numerous studies, but whether they can be used for the treatment of related cardiovascular diseases needs to be verified in future clinical studies. Herein, we summarize recent advances regarding mitochondrial dynamics in multiple cells involved in vascular remodeling and associated target-organ damage.

The Autotaxin-LPA Axis Emerges as a Novel Regulator of Smooth Muscle Cell Phenotypic Modulation during Intimal Hyperplasia

Neointimal hyperplasia is characterized by a loss of the contractile phenotype of vascular smooth muscle cells (VSMCs). Our group has recently shown that VSMC proliferation and migration are mediated by lysophosphatidic acid (LPA) during restenosis, but the role of autotaxin (ATX; lysophospholipase D), which produces LPA, remains unclear. Endothelial denudation of the mouse carotid artery was performed to induce neointimal hyperplasia, and the extent of damage caused by the ATX-LPA axis was assessed in VSMCs. We observed the upregulation of ATX activity (p < 0.0002) in the injured carotid artery using an AR2 probe fluorescence assay. Further, the tissue carotid LPA levels were elevated 2.7-fold in carotid vessels, augmenting neointimal hyperplasia. We used an electrical cell-substrate impedance sensor (ECIS) to measure VSMC proliferation and migration. Treatment with an ATX inhibitor (PF8380) or LPA receptor inhibitor (Ki16425) attenuated VSMC proliferation (extracellular signal-regulated kinases) activity and migration in response to recombinant ATX. Indeed, PF8380 treatment rescued the aggravated post-wire injury neointima formation of carotid arteries. The upregulation of ATX following vessel injury leads to LPA production in VSMCs, favoring restenosis. Our observations suggest that inhibition of the ATX-LPA axis could be therapeutically targeted in restenosis to minimize VSMC phenotypic modulation and inflammation after vascular injury.

GALNT3 protects against vascular calcification by reducing oxidative stress and apoptosis of smooth muscle cells

Vascular calcification (VC) is the pathological deposition of calcium and phosphate minerals in blood vessels, which is a common complication of atherosclerosis. Polypeptide N-acetylgalactosamine transferase 3 (GALNT3) initiates O-glycosylation of proteins through addition of GalNAc to specific serine or threonine residues. Our previous studies revealed the potent role of GALNT3 in atherosclerosis, whereas the precise mechanisms remain obscure. This study investigated the regulatory effect and mechanism of GALNT3 on VC. Firstly, GALNT3 was overexpressed and knocked down by adenovirus in high-phosphate induced calcified HASMCs and overexpressed by adeno-associated virus in vitamin D3-induced arterial calcification mice. We showed that the calcium deposition and mRNA expression of osteogenic markers MSX2, ALPL, and Runx2 were all significantly reduced with GALNT3 overexpression. Moreover, overexpression of GALNT3 significantly down-regulated the expression of the oxidative stress markers Nox2 and Nox4, up-regulated total antioxidant capacity, decreased the expression of pro-inflammatory factors IL-1β, TNF-α and IL-8, matrix metalloproteinases MMP2 and MMP9, as well as reduced the apoptosis of cells in phosphate induced HASMCs. Furthermore, Vicia Villosa Lectin (VVL) pull down and TNFR1 immunoprecipitation assays showed that GALNT3 overexpression increased O-GalNAcylation of TNFR1 and blocked the activation of NF-κB signaling pathway. In addition, GALNT3 attenuates vitamin D3-induced aortic calcification in mice by alleviating oxidative stress and apoptosis of smooth muscle cells. In conclusion, this study indicates that GALNT3 protects against VC by reducing oxidative stress, vascular inflammation, and apoptosis of smooth muscle cells through the TNFR1/NF-κB signaling pathway. Thus, GALNT3 may be a potential therapeutic target for VC.

Yes-Associated Protein and Transcriptional Coactivator with PDZ-Binding Motif in Cardiovascular Diseases

Yes-associated protein (YAP, also known as YAP1) and its paralogue TAZ (with a PDZ-binding motif) are transcriptional coactivators that switch between the cytoplasm and nucleus and regulate the organ size and tissue homeostasis. This review focuses on the research progress on YAP/TAZ signaling proteins in myocardial infarction, cardiac remodeling, hypertension and coronary heart disease, cardiomyopathy, and aortic disease. Based on preclinical studies on YAP/TAZ signaling proteins in cellular/animal models and clinical patients, the potential roles of YAP/TAZ proteins in some cardiovascular diseases (CVDs) are summarized.

The BioHybrid Assay: A Novel Method for Determining Calcification Propensity

Vascular calcification is an active pathological process, characterised by cellular dysregulation and subsequent changes to the extracellular environment. In vivo detection of vascular calcification is only possible late stage via computed tomography, and there is no single biomarker for detecting progression of vascular calcification. There is an unmet clinical need to determine progression of vascular calcification in vulnerable patients. This is especially needed in chronic kidney disease (CKD) patients where there is a correlation of cardiovascular disease with declining renal status. We hypothesised that the entirety of circulating components should be taken into consideration with vessel wall cells to determine real-time vascular calcification development. In this protocol we describe the isolation and characterisation of human primary vascular smooth muscle cells (hpVSMCs), and the addition of human serum or plasma to hpVSMCs in a calcification assay and analysis. The BioHybrid analysis of biological changes to in vitro hpVSMC calcification is reflective of in vivo vascular calcification status. We suggest this analysis can discriminate between CKD patient cohorts and has the potential for wider application for risk factor determination in CKD and the general population.

Cathepsin D Attenuates the Proliferation of Vascular Smooth Muscle Cells Induced by the AGE/RAGE Pathway by Suppressing the ERK Signal

BACKGROUND

In this study, we aimed to clarify the role and mechanism by which Cathepsin D (CTSD) mediates the advanced glycation end products (AGEs)-induced proliferation of vascular smooth muscle cells (VSMCs).

METHODS

We conducted a Western blotting assay and co-immunoprecipitation assay to detect the expression of target proteins and the interaction between different proteins. Cell Counting Kit-8 (CCK-8) assay and 5- ethynyl-2'-deoxyuridine (EdU) were used to evaluate the proliferation.

RESULTS

AGEs significantly promoted phenotypic switching and proliferation of VSMCs in a concentration-dependent manner. This effect of AGEs was accompanied by inhibition of CTSD. Both the proliferation of VSMCs and inhibition of CTSD induced by AGEs could be attenuated by the specific inhibitor of the receptor for advanced glycation end products (RAGE), FPS-ZM1. Overexpression of CTSD significantly alleviated these effects of AGEs on VSMCs. The mechanism of CTSD action in VSMCs was also explored. Overexpression of CTSD reduced the activation of p-ERK caused by AGEs. By contrast, the knockdown of CTSD, elicited using a plasmid containing short hairpin RNA (shRNA) against CTSD, further increased the activation of p-ERK compared to AGEs alone. Additionally, co-immunoprecipitation studies revealed an endogenous interaction between CTSD, a protease, and p-ERK, its potential substrate.

CONCLUSION

It has been demonstrated that CTSD downregulates the level of phosphorylated ERK by degrading its target, and this interaction plays a critical role in the proliferation of VSMCs induced by the AGE/RAGE axis. These results provide a novel insight into the prevention and treatment of vascular complications in diabetes.

Piezo1 in endothelial cells is involved in vitamin D-induced vascular calcification

The relationship between the Piezo1 channel of vascular endothelial cells and vascular calcification is unknown. In this study, after subcutaneous injection of vitamin D for 10 consecutive days, the mice showed an increase in serum calcium, aortic calcium content, vascular tension and pulse wave velocity. Piezo1channel antagonist, GsMTx4 alleviated arteriosclerosis and decreased the aortic calcium content, while Piezo1 agonist Yoda1 produced opposite effect. In addition, activation of Piezo1 by Yoda1 impaired the function of human umbilical vein endothelial cells (HUVECs), as evidenced by further decreased production of NO, reduction in expression levels of eNOS, MMP-2, PCNA and VEGFA. When co-culture of HUVECs and vascular smooth muscle cells (VSMCs), activation of Piezo1 in HUVECs enhanced expression levels of calcification-related SOX9 and Runx2 genes, increased ALP activity and calcium deposition in VSMCs. We concluded that Piezo1 in endothelial cells is involved in the pathogenesis of vascular calcification. This study provides a new experimental basis for the prevention and treatment of vascular calcification.

Deletion of large-conductance calcium-activated potassium channels promotes vascular remodelling through the CTRP7-mediated PI3K/Akt signaling pathway

The large-conductance calcium-activated potassium (BK) channel is a critical regulator and potential therapeutic target of vascular tone and architecture, and abnormal expression or dysfunction of this channel is linked to many vascular diseases. Vascular remodelling is the early pathological basis of severe vascular diseases. Delaying the progression of vascular remodelling can reduce cardiovascular events, but the pathogenesis remains unclear. To clarify the role of BK channels in vascular remodelling, we use rats with BK channel α subunit knockout (BK α ^‒/‒). The results show that BK α ^‒/‒ rats have smaller inner and outer diameters, thickened aortic walls, increased fibrosis, and disordered elastic fibers of the aortas compared with WT rats. When the expression and function of BK α are inhibited in human umbilical arterial smooth muscle cells (HUASMCs), the expressions of matrix metalloproteinase 2 (MMP2), MMP9, and interleukin-6 are enhanced, while the expressions of smooth muscle cell contractile phenotype proteins are reduced. RNA sequencing, bioinformatics analysis and qPCR verification show that C1q/tumor necrosis factor-related protein 7 ( CTRP7) is the downstream target gene. Furthermore, except for that of MMPs, a similar pattern of IL-6, smooth muscle cell contractile phenotype proteins expression trend is observed after CTRP7 knockdown. Moreover, knockdown of both BK α and CTRP7 in HUASMCs activates PI3K/Akt signaling. Additionally, CTRP7 is expressed in vascular smooth muscle cells (VSMCs), and BK α deficiency activates the PI3K/Akt pathway by reducing CTRP7 level. Therefore, we first show that BK channel deficiency leads to vascular remodelling. The BK channel and CTRP7 may serve as potential targets for the treatment of cardiovascular diseases.

Mechanism of Hypoxia-Mediated Smooth Muscle Cell Proliferation Leading to Vascular Remodeling

Vascular remodeling refers to changes in the size, contraction, distribution, and flow rate of blood vessels and even changes in vascular function. Vascular remodeling can cause cardiovascular and cerebrovascular diseases. It can also lead to other systemic diseases, such as pulmonary hypertension, pulmonary atherosclerosis, chronic obstructive pulmonary disease, stroke, and ascites of broilers. Hypoxia is one of the main causes of vascular remodeling. Prolonged hypoxia or intermittent hypoxia can lead to loss of lung ventilation, causing respiratory depression, irregular respiratory rhythms, and central respiratory failure. Animals that are unable to adapt to the highland environment are also prone to sustained constriction of the small pulmonary arteries, increased resistance to pulmonary circulation, and impaired blood circulation, leading to pulmonary hypertension and right heart failure if they live in a highland environment for long periods of time. However, limited studies have been found on the relationship between hypoxia and vascular remodeling. Therefore, this review will explore the relationship between hypoxia and vascular remodeling from the aspects of endoplasmic reticulum stress, mitochondrial dysfunction, abnormal calcium channel, disordered cellular metabolism, abnormal expression of miRNA, and other factors. This will help to understand the detailed mechanism of hypoxia-mediated smooth muscle cell proliferation and vascular remodeling for the better treatment and management of diseases due to vascular remodeling.

Calcium Signalling in Heart and Vessels: Role of Calmodulin and Downstream Calmodulin-Dependent Protein Kinases

Cardiovascular disease is the major cause of death worldwide. The success of medication and other preventive measures introduced in the last century have not yet halted the epidemic of cardiovascular disease. Although the molecular mechanisms of the pathophysiology of the heart and vessels have been extensively studied, the burden of ischemic cardiovascular conditions has risen to become a top cause of morbidity and mortality. Calcium has important functions in the cardiovascular system. Calcium is involved in the mechanism of excitation-contraction coupling that regulates numerous events, ranging from the production of action potentials to the contraction of cardiomyocytes and vascular smooth muscle cells. Both in the heart and vessels, the rise of intracellular calcium is sensed by calmodulin, a protein that regulates and activates downstream kinases involved in regulating calcium signalling. Among them is the calcium calmodulin kinase family, which is involved in the regulation of cardiac functions. In this review, we present the current literature regarding the role of calcium/calmodulin pathways in the heart and vessels with the aim to summarize our mechanistic understanding of this process and to open novel avenues for research.

Vascular Smooth Muscle Cells Phenotypic Switching in Cardiovascular Diseases

Vascular smooth muscle cells (VSMCs), the major cell type in the arterial vessel wall, have a contractile phenotype that maintains the normal vessel structure and function under physiological conditions. In response to stress or vascular injury, contractile VSMCs can switch to a less differentiated state (synthetic phenotype) to acquire the proliferative, migratory, and synthetic capabilities for tissue reparation. Imbalances in VSMCs phenotypic switching can result in a variety of cardiovascular diseases, including atherosclerosis, in-stent restenosis, aortic aneurysms, and vascular calcification. It is very important to identify the molecular mechanisms regulating VSMCs phenotypic switching to prevent and treat cardiovascular diseases with high morbidity and mortality. However, the key molecular mechanisms and signaling pathways participating in VSMCs phenotypic switching have still not been fully elucidated despite long-term efforts by cardiovascular researchers. In this review, we provide an updated summary of the recent studies and systematic knowledge of VSMCs phenotypic switching in atherosclerosis, in-stent restenosis, aortic aneurysms, and vascular calcification, which may help guide future research and provide novel insights into the prevention and treatment of related diseases.

Development of a cyclic-inverso AHSG/Fetuin A-based peptide for inhibition of calcification in osteoarthritis

OBJECTIVE

Ectopic calcification is an important contributor to chronic diseases, such as osteoarthritis. Currently, no effective therapies exist to counteract calcification. We developed peptides derived from the calcium binding domain of human Alpha-2-HS-Glycoprotein (AHSG/Fetuin A) to counteract calcification.

METHODS

A library of seven 30 amino acid (AA) long peptides, spanning the 118 AA Cystatin 1 domain of AHSG, were synthesized and evaluated in an in vitro calcium phosphate precipitation assay. The best performing peptide was modified (cyclic, retro-inverso and combinations thereof) and evaluated in cellular calcification models and the rat Medial Collateral Ligament Transection + Medial Meniscal Tear (MCLT + MMT) osteoarthritis model.

RESULTS

A cyclic peptide spanning AA 1-30 of mature AHSG showed clear inhibition of calcium phosphate precipitation in the nM-pM range that far exceeded the biological activity of the linear peptide variant or bovine Fetuin. Biochemical and electron microscopy analyses of calcium phosphate particles revealed a similar, but distinct, mode of action in comparison with bFetuin. A cyclic-inverso variant of the AHSG 1-30 peptide inhibited calcification of human articular chondrocytes, vascular smooth muscle cells and during osteogenic differentiation of bone marrow derived stromal cells. Lastly, we evaluated the effect of intra-articular injection of the cyclic-inverso AHSG 1-30 peptide in a rat osteoarthritis model. A significant improvement was found in histopathological osteoarthritis score and animal mobility. Serum levels of IFNγ were found to be lower in AHSG 1-30 peptide treated animals.

CONCLUSIONS

The cyclic-inverso AHSG 1-30 peptide directly inhibits the calcification process and holds the potential for future application in osteoarthritis.

Inhibitory effects of 6'-sialyllactose on angiotensin II-induced proliferation, migration, and osteogenic switching in vascular smooth muscle cells

Excessive production and migration of vascular smooth muscle cells (VSMCs) are associated with vascular remodeling that causes vascular diseases, such as restenosis and hypertension. Angiotensin II (Ang II) stimulation is a key factor in inducing abnormal VSMC function. This study aimed to investigate the effects of 6'-sialyllactose (6'SL), a human milk oligosaccharide, on Ang II-stimulated cell proliferation, migration and osteogenic switching in rat aortic smooth muscle cells (RASMCs) and human aortic smooth muscle cells (HASMCs). Compared with the control group, Ang II increased cell proliferation by activating MAPKs, including ERK1/2/p90RSK/Akt/mTOR and JNK pathways. However, 6'SL reversed Ang II-stimulated cell proliferation and the ERK1/2/p90RSK/Akt/mTOR pathways in RASMCs and HASMCs. Moreover, 6'SL suppressed Ang II-stimulated cell cycle progression from G0/G1 to S and G2/M phases in RASMCs. Furthermore, 6'SL effectively inhibited cell migration by downregulating NF-κB-mediated MMP2/9 and VCAM-1 expression levels. Interestingly, in RASMCs, 6'SL attenuated Ang II-induced osteogenic switching by reducing the production of p90RSK-mediated c-fos and JNK-mediated c-jun, leading to the downregulation of AP-1-mediated osteopontin production. Taken together, our data suggest that 6'SL inhibits Ang II-induced VSMC proliferation and migration by abolishing the ERK1/2/p90RSK-mediated Akt and NF-κB signaling pathways, respectively, and osteogenic switching by suppressing p90RSK- and JNK-mediated AP-1 activity.

Development of Biodegradable Polymeric Stents for the Treatment of Cardiovascular Diseases

Cardiovascular disease has become the leading cause of death. A vascular stent is an effective means for the treatment of cardiovascular diseases. In recent years, biodegradable polymeric vascular stents have been widely investigated by researchers because of its degradability and clinical application potential for cardiovascular disease treatment. Compared to non-biodegradable stents, these stents are designed to degrade after vascular healing, leaving regenerated healthy arteries. This article reviews and summarizes the recent advanced methods for fabricating biodegradable polymeric stents, including injection molding, weaving, 3D printing, and laser cutting. Besides, the functional modification of biodegradable polymeric stents is also introduced, including visualization, anti-thrombus, endothelialization, and anti-inflammation. In the end, the challenges and future perspectives of biodegradable polymeric stents were discussed.

Vascular Smooth Muscle Cell Neutral Sphingomyelinase 2 in the Release of Exosomes and Vascular Calcification

Vascular calcification (VC) is the pathological precipitation of calcium salts in the walls of blood vessels. It is a risk factor for cardiovascular events and their associated mortality. VC can be observed in a variety of cardiovascular diseases and is most prominent in diseases that are associated with dysregulated mineral homeostasis such as in chronic kidney disease. Local factors and mechanisms underlying VC are still incompletely understood, but it is appreciated that VC is a multifactorial process in which vascular smooth muscle cells (VSMCs) play an important role. VSMCs participate in VC by releasing extracellular vesicles (EVs), the extent, composition, and propensity to calcify of which depend on VSMC phenotype and microenvironment. Currently, no targeted therapy is available to treat VC. In-depth knowledge of molecular players of EV release and the understanding of their mechanisms constitute a vital foundation for the design of pharmacological treatments to combat VC effectively. This review highlights our current knowledge of VSMCs in VC and focuses on the biogenesis of exosomes and the role of the neutral Sphingomyelinase 2 (nSMase2).

Development of hydrogen sulfide donors for anti-atherosclerosis therapeutics research: Challenges and future priorities

Hydrogen sulfide (H₂S), a gas transmitter found in eukaryotic organisms, plays an essential role in several physiological processes. H₂S is one of the three primary biological gas transmission signaling mediators, along with nitric oxide and carbon monoxide. Several animal and in vitro experiments have indicated that H₂S can prevent coronary endothelial mesenchymal transition, reduce the expression of endothelial cell adhesion molecules, and stabilize intravascular plaques, suggesting its potential role in the treatment of atherosclerosis (AS). H₂S donors are compounds that can release H₂S under certain circumstances. Development of highly targeted H₂S donors is a key imperative as these can allow for in-depth evaluation of the anti-atherosclerotic effects of exogenous H₂S. More importantly, identification of an optimal H₂S donor is critical for the creation of H₂S anti-atherosclerotic prodrugs. In this review, we discuss a wide range of H₂S donors with anti-AS potential along with their respective transport pathways and design-related limitations. We also discuss the utilization of nano-synthetic technologies to manufacture H₂S donors. This innovative and effective design example sheds new light on the production of highly targeted H₂S donors.

Adropin Inhibits Vascular Smooth Muscle Cell Osteogenic Differentiation to Alleviate Vascular Calcification via the JAK2/STAT3 Signaling Pathway

Vascular calcification is characterized as the deposition of hydroxyapatite mineral in the form of calcium-phosphate complexes in the vasculature. Transdifferentiation between vascular smooth muscle cells (VSMCs) and osteoblast-like cells is considered essential in the progression of vascular calcification. The pathophysiological mechanisms underlying vascular calcification and VSMC osteogenic differentiation remain to be fully elucidated, and the development of novel therapies is required. In the present study, PCR and western blot analysis were conducted to quantify the mRNA and protein expression levels of calcification-associated markers (bone morphogenetic protein 2, alkaline phosphatase, osteoprotegerin, osteocalcin, and runt-related transcription factor 2) and adropin in VSMCs and rat vascular tissues. The calcification of VSMCs was assessed using alizarin red staining. Moreover, adropin expression levels in VSMCs were analyzed using immunofluorescence. Lentiviral transfection and small interfering RNA were used for overexpression and knockdown of adropin in VSMCs, respectively. The results demonstrated that adropin alleviated vascular calcification in vivo. Moreover, adropin also inhibited osteogenic differentiation and the calcification of VSMCs in vitro. Notably, results of the present study revealed that the tyrosine protein kinase JAK2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway played a key role in the aforementioned inhibition. In conclusion, the results of the present study demonstrated that adropin inhibited VSMC osteogenic differentiation to alleviate vascular calcification via the JAK2/STAT3 signaling pathway.

Role of glycolysis in the development of atherosclerosis

Atherosclerosis is a chronic inflammatory vascular disease associated with atherosclerotic plaques and endothelial dysfunction, inflammation, and plaque formation. Glycolysis is a conservative and rigorous biological process that decomposes glucose into pyruvate. Its function is to provide the body with energy and intermediate products required for life activities. However, abnormalities in glycolytic flux during the progression of atherosclerosis accelerate disease progression. Here, we review the role of glycolysis in the development of atherosclerosis to provide new ideas for developing novel anti-atherosclerosis strategies.

Icariside II Restores Vascular Smooth Muscle Cell Contractile Phenotype by Enhancing the Focal Adhesion Signaling Pathway in the Rat Vascular Remodeling Model

Vascular smooth muscle cell (VSMC) phenotypic transition represents the fundamental pathophysiological alteration in the vascular remodeling process during the initiation and progression of cardiovascular diseases. Recent studies have revealed that Icariside II (ICS-II), a flavonol glycoside derived from the traditional Chinese medicine Herba Epimedii, exhibited therapeutic effects in various cardiovascular diseases. However, the therapeutic efficacy and underlying mechanisms of ICS-II regarding VSMC phenotypic transition were unknown. In this study, we investigated the therapeutic effects of ICS-Ⅱ on vascular remodeling with a rat’s balloon injury model in vivo. The label-free proteomic analysis was further implemented to identify the differentially expressed proteins (DEPs) after ICS-II intervention. Gene ontology and the pathway enrichment analysis were performed based on DEPs. Moreover, platelet-derived growth factor (PDGF-BB)-induced primary rat VSMC was implemented to verify the restoration effects of ICS-II on the VSMC contractile phenotype. Results showed that ICS-II could effectively attenuate the vascular remodeling process, promote SMA-α protein expression, and inhibit OPN expression in vivo. The proteomic analysis identified 145 differentially expressed proteins after ICS-II intervention. Further, the bioinformatics analysis indicated that the focal adhesion signaling pathway was enriched in the ICS-II group. In vitro studies showed that ICS-II suppressed VSMC proliferation and migration, and promoted VSMC contractile phenotype by modulating the focal adhesion signaling pathway. Taken together, our results suggest that ICS-II attenuates the vascular remodeling process and restores the VSMC contractile phenotype by promoting the focal adhesion pathway.

Proteomics of restenosis model in LDLR-deficient hamsters coupled with the proliferative rat vascular smooth muscle cells reveals a new mechanism of vascular remodeling diseases

A major pathological mechanism involved in vascular remodeling diseases is the proliferation and migration of vascular smooth muscle cells. The lipid distribution of golden hamsters is similar to that of humans, which makes them an excellent study model for studying the pathogenesis and molecular characteristics of vascular remodeling diseases. We performed proteomic analysis on Sprague Dawley rat VSMCs (rVSMCs) and restenosis hamsters with low-density lipoprotein receptor (LDLR) deficiency as part of this study. We have also performed the enrichment analysis of differentially modified proteins in regards to Gene Ontology, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and protein domain. 1070 differentially abundant proteins were assessed in rVSMCs before and after platelet-derived growth factor-BB (PDGF-BB) stimulation. Specifically, 1246 proteins displayed significant differences in the restenosis model in LDLR-deficient hamsters. An analysis of crosstalk between LDLR^+/- hamsters artery restenosis and proliferating rVSMCs revealed 130 differentially expressed proteins, including 67 up-regulated proteins and 63 downregulated proteins. Enrichment analysis with KEGG showed differential proteins to be mainly concentrated in metabolic pathways. There are numerous differentially abundant proteins but particularly two proteins (phosphofructokinase 1 of liver type and lactate dehydrogenase A) were found to be up-regulated by PDGF-BB stimulation of rVSMCs and in a restenosis model of hamsters with LDLR^+/- expression. SIGNIFICANCE: Based on bioinformatics, we have found glycolysis pathway plays an important role in both the LDLR^+/- hamsters restenosis model and the proliferation of rVSMCs. Some key glycolysis enzymes may likely be developed either as new biomarkers or drug targets for vascular remodeling diseases.

The Role of Sirtuins in Osteogenic Differentiation of Vascular Smooth Muscle Cells and Vascular Calcification

Vascular calcification (VC) is a common pathological change in many chronic diseases, such as diabetes and chronic kidney disease. It is mainly deposited in the intima and media of vessels in the form of hydroxyapatite. Recently, a lot of research has been performed to show that VC is associated with various cellular stresses, such as hyperphosphate, hyperglycemia and oxidative stress. Unfortunately, our understanding of the pathogenesis of calcification is far from comprehensive. Sirtuins belong to a family of class III highly conserved deacetylases that are involved in the regulation of biological and cellular processes including mitochondrial biogenesis, metabolism, oxidative stress, inflammatory response, DNA repair, etc. Numerous studies have shown that sirtuins might play protective roles in VC, and restoring the activity of sirtuins may be a potentially effective treatment for VC. However, the exact mechanism of their vascular protection remains unclear. Here, we reviewed the roles of sirtuins in the osteogenic transformation of vascular smooth muscle cells and the development of VC. We also elucidated the applications of sirtuins agonists for the treatment of VC.

Stem Cell-derived Exosomal MicroRNA as Therapy for Vascular Age-related Diseases

Vascular age-related diseases describe a group of age-related chronic diseases that result in a considerable healthcare burden to society. Vascular aging includes structural changes and dysfunctions of endothelial cells (ECs) and smooth muscle cells (SMCs) in blood vessels. Compared with conventional treatment for vascular age-related diseases, stem cell (SC) therapy elicits better anti-aging effects viathe inhibition/delay ECs and SMCs from entering senescence. Exosomal noncoding RNA (ncRNAs) in vascular aging and stem cell-derived exosomal microRNAs (SCEV-miRNAs), especially in mesenchymal stem cells, have an important role in the development of age-related diseases. This review summarizes SCEV-miRNAs of diverse origins that may play a vital role in treating subclinical and clinical stages of vascular age-related disorders. We further explored possible age-related pathways and molecular targets of SCEV-miRNA, which are associated with dysfunctions of ECs and SMCs in the senescent stage. Moreover, the perspectives and difficulties of SCEV-miRNA clinical translation are discussed. This review aims to provide greater understanding of the biology of vascular aging and to identify critical therapeutic targets for SCEV-miRNAs. Though still in its infancy, the potential value of SCEV-miRNAs for vascular age-related diseases is clear.

The Effect of Chronic Immunosuppressive Regimens Treatment on Aortal Media Morphology and the Balance between Matrix Metalloproteinases (mmp-2 and mmp-9) and Their Inhibitors in the Abdominal Aorta of Rats

Immunosuppressive drugs are widely and chronically used to avoid graft rejection in transplant recipients. However, they are also known to have organotoxic effects and can exert numerous side effects. The aim of this study was to assess whether the chronic treatment of rats with the most commonly used clinical immunosuppressive regimens in organ recipients had an effect on the morphology and function of the aorta. The rats were divided into five groups and each group was chronically treated with different sets of three immunosuppressive drugs (TRG, CRG, MRG, CMG, TMG) for 6 months. The changes were most profound in calcineurin inhibitor-based protocols. TMG protocol treatment was characterized by the most numerous alterations such as morphological changes, changes in the thickness of the tunic media, wider distances between elastic lamellae, an increase in the number of vSMCs and changes in collagen deposition. We concluded that the morphological changes were connected with MMP-2 and MMP-9/TIMP-2 and TIMP-1 imbalances, which was also determined and noticed.

Mammalian Sirtuins and Their Relevance in Vascular Calcification

Cardiovascular diseases are a group of diseases with high morbidity and mortality that affect millions of people each year. Vascular calcification (VC) is an active process that involves the mineral deposition of calcium-phosphate complexes. VC is closely related to cardiovascular diseases, such as hypertension, heart failure, and calcific aortic stenosis, and is a type of ectopic calcification that occurs in the vessel walls. The sirtuins (silent mating-type information regulation 2; SIRTs), are a family of histone deacetylases whose function relies on nicotinamide adenine dinucleotide (NAD+). They have non-negligible functions in the regulation of energy metabolism, senescence, apoptosis, and other biological processes. Sirtuins have important effects on bone homeostasis and VC processes that share many similarities with bone formation. Sirtuins have been confirmed to deacetylate a variety of target proteins related to the occurrence and development of VC, thereby affecting the process of VC and providing new possibilities for the prevention and treatment of cardiovascular diseases. To facilitate the understanding of vascular calcification and accelerate the development of cardiovascular drugs, we reviewed and summarized recent research progress on the relationship between different types of sirtuins and VC.

CircRNA-miRNA interactions in atherogenesis

Atherosclerosis is the major cause of coronary artery disease (CAD) which includes unstable angina, myocardial infarction, and heart failure. The onset of atherogenesis, a process of atherosclerotic lesion formation in the intima of arteries, is driven by lipid accumulation, a vicious cycle of reactive oxygen species (ROS)-induced oxidative stress and inflammatory reactions leading to endothelial cell (EC) dysfunction, vascular smooth muscle cell (VSMC) activation, and foam cell formation which further fuel plaque formation and destabilization. In recent years, there is a surge in the number of publications reporting the involvement of circular RNAs (circRNAs) in the pathogenesis of cardiovascular diseases, cancers, and metabolic syndromes. These studies have advanced our understanding on the biological functions of circRNAs. One of the most common mechanism of action of circRNAs reported is the sponging of microRNAs (miRNAs) by binding to the miRNAs response element (MRE), thereby indirectly increases the transcription of their target messenger RNAs (mRNAs). Individual networks of circRNA-miRNA-mRNA associated with atherogenesis have been extensively reported, however, there is a need to connect these findings for a complete overview. This review aims to provide an update on atherogenesis-related circRNAs and analyze the circRNA-miRNA-mRNA interactions in atherogenesis. The atherogenic mechanisms and clinical relevance of each atherogenesis-related circRNA were systematically discussed for better understanding of the knowledge gap in this area.

Potential Actions of Baicalein for Preventing Vascular Calcification of Smooth Muscle Cells In Vitro and In Vivo

Vascular calcification (VC) is associated with cardiovascular disease. Baicalein, a natural flavonoid extract of Scutellaria baicalensis rhizome has several biological properties which may inhibit VC. We investigated whether baicalein suppresses Runt-related transcription factor 2 (Runx2) and bone morphogenetic protein 2 (BMP-2) and upregulates smooth muscle 22-alpha (SM22-α) and alpha-smooth muscle actin (α-SMA). In an in vitro experiment, primary rat aortic vascular smooth muscle cells (VSMCs) were pretreated with 0.1, 1, and 5 μM baicalein, followed by β-glycerophosphate (β-GP) to induce calcification. In an in vivo experiment, VC was generated by vitamin D3 plus nicotine (VDN) administration to male Sprague Dawley (SD) rats randomly assigned into a control group, a VC group, a VC group pretreated with baicalein, and a baicalein alone group. Each group comprised 10 rats. Left ventricular (LV) morphology, function and performance were assessed by echocardiography. Calcium content was measured by Alizarin red S staining and alkaline phosphatase (ALP) activity assays. Apoptotic VSMCs were detected by flow cytometry. Protein levels and superoxide changes were evaluated using Western blotting and immunofluorescence assays respectively. Plasma malondialdehyde (MDA) was assayed. Baicalein pretreatment significantly reduced calcium content in calcified VSMCs (p < 0.001) as well as in VC rat aortic smooth muscle (p < 0.001). Additionally, ALP activity was decreased in calcified VSMCs and VC rat aortic smooth muscle (p < 0.001). Apoptosis was significantly attenuated by 1 μM baicalein pretreatment in calcified VSMCs. Runx2 and BMP-2 expressions were downregulated by the baicalein in calcified VSMCs. Baicalein pretreatment increased typical VSMCs markers SM22-α and α-SMA in calcified VSMCs. Baicalein pretreatment was associated with adverse changes in LV morphometry. Markers of oxidative stress declined, and endogenous antioxidants increased in VC rats pretreated with baicalein. Baicalein mitigates VC through the inhibition of Runx2/BMP-2 signaling pathways, enhancement of vascular contractile phenotype and oxidative stress reduction. However, our study is of basic experimental design; more advanced investigations to identify other molecular regulators of VC and their mechanisms of action is required.

New Insight in HDACs: Potential Therapeutic Targets for the Treatment of Atherosclerosis

Atherosclerosis (AS) features include progressive hardening and reduced elasticity of arteries. AS is the leading cause of morbidity and mortality. An increasing amount of evidence showed that epigenetic modifications on genes serve are a main cause of several diseases, including AS. Histone deacetylases (HDACs) promote the deacetylation at lysine residues, thereby condensing the chromatin structures and further inhibiting the transcription of downstream genes. HDACs widely affect various physiological and pathological processes through transcriptional regulation or deacetylation of other non-histone proteins. In recent years, the role of HDACs in vascular systems has been revealed, and their effects on atherosclerosis have been widely reported. In this review, we discuss the members of HDACs in vascular systems, determine the diverse roles of HDACs in AS, and reveal the effects of HDAC inhibitors on AS progression. We provide new insights into the potential of HDAC inhibitors as drugs for AS treatment.

Role of miR-181b/Notch1 Axis in circ_TNPO1 Promotion of Proliferation and Migration of Atherosclerotic Vascular Smooth Muscle Cells

Background

The role and expression level change in circ_TNPO1 (hsa_circ_0072951) in atherosclerosis (AS) and VSMC dysfunction remain unknown. In this study, we try to explore the effects of circ_TNPO1 on oxidized low-density lipoprotein (ox-LDL)-induced human vascular smooth muscle cell (VSMC) excessive proliferation and migration, and the potential molecular mechanism.

Methods

Quantitative real-time polymerase chain reaction (RT-qPCR) and western blot experiment were used to detect the serum samples from AS patients and healthy controls. CCK-8, Transwell, and the dual-luciferase reporter gene assay were used to detect the cell biology.

Results

In human AS serum and ox-LDL-induced VSMCs, circ_TNPO1 was increased, whereas miR-181b was decreased. Silencing circ_TNPO1 inhibited proliferation and migration activity and reduced protein expression of PCNA, Ki-67, MMP2, and E-cadherin and promoted N-cadherin protein expression in ox-LDL induced VSMCs. Remarkably, miR-181b knockdown or Notch1 overexpression could efficiently offset the proliferation and migration inhibiting effect of circ_TNPO1 knockdown in ox-LDL-induced VSMCs. Furthermore, a molecular mechanism study pointed out that circ_TNPO1 and Notch1 are direct-acting targets of miR-181b.

Conclusions

In conclusion, our study indicated that circ_TNPO1 promotes the proliferation and migration progression of VSMCs in atherosclerosis through the miR-181b/Notch1 axis.

Natural Flavonoids Derived From Fruits Are Potential Agents Against Atherosclerosis

Atherosclerosis, as a chronic inflammatory response, is one of the main causes of cardiovascular diseases. Atherosclerosis is induced by endothelial cell dysfunction, migration and proliferation of smooth muscle cells, accumulation of foam cells and inflammatory response, resulting in plaque accumulation, narrowing and hardening of the artery wall, and ultimately leading to myocardial infarction or sudden death and other serious consequences. Flavonoid is a kind of natural polyphenol compound widely existing in fruits with various structures, mainly including flavonols, flavones, flavanones, flavanols, anthocyanins, isoflavones, and chalcone, etc. Because of its potential health benefits, it is now used in supplements, cosmetics and medicines, and researchers are increasingly paying attention to its role in atherosclerosis. In this paper, we will focus on several important nodes in the development of atherosclerotic disease, including endothelial cell dysfunction, smooth muscle cell migration and proliferation, foam cell accumulation and inflammatory response. At the same time, through the classification of flavonoids from fruits, the role and potential mechanism of flavonoids in atherosclerosis were reviewed, providing a certain direction for the development of fruit flavonoids in the treatment of atherosclerosis drugs.

Extracellular Vesicles From LPS-Treated Macrophages Aggravate Smooth Muscle Cell Calcification by Propagating Inflammation and Oxidative Stress

Background: Vascular calcification (VC) is a cardiovascular complication associated with a high mortality rate among patients with diseases such as atherosclerosis and chronic kidney disease. During VC, vascular smooth muscle cells (VSMCs) undergo an osteogenic switch and secrete a heterogeneous population of extracellular vesicles (EVs). Recent studies have shown involvement of EVs in the inflammation and oxidative stress observed in VC. We aimed to decipher the role and mechanism of action of macrophage-derived EVs in the propagation of inflammation and oxidative stress on VSMCs during VC.

Methods: The macrophage murine cell line RAW 264.7 treated with lipopolysaccharide (LPS-EK) was used as a cellular model for inflammatory and oxidative stress. EVs secreted by these macrophages were collected by ultracentrifugation and characterized by transmission electron microscopy, cryo-electron microscopy, nanoparticle tracking analysis, and the analysis of acetylcholinesterase activity, as well as that of CD9 and CD81 protein expression by western blotting. These EVs were added to a murine VSMC cell line (MOVAS-1) under calcifying conditions (4 mM Pi—7 or 14 days) and calcification assessed by the o-cresolphthalein calcium assay. EV protein content was analyzed in a proteomic study and EV cytokine content assessed using an MSD multiplex immunoassay.

Results: LPS-EK significantly decreased macrophage EV biogenesis. A 24-h treatment of VSMCs with these EVs induced both inflammatory and oxidative responses. LPS-EK-treated macrophage-derived EVs were enriched for pro-inflammatory cytokines and CAD, PAI-1, and Saa3 proteins, three molecules involved in inflammation, oxidative stress, and VC. Under calcifying conditions, these EVs significantly increase the calcification of VSMCs by increasing osteogenic markers and decreasing contractile marker expression.

Conclusion: Our results show that EVs derived from LPS-EK–treated-macrophages are able to induce pro-inflammatory and pro-oxidative responses in surrounding cells, such as VSMCs, thus aggravating the VC process.

Lower urinary tract symptoms in patients with small prostates: Smooth muscle proliferation and calcification might be causative factors

OBJECTIVES

The current study is designed to evaluate and compare the histological changes in the surgical samples of prostate taken from patients undergoing transurethral resection of prostate (TURP) for benign prostate hyperplasia (BPH) with different sizes.

METHODS

Prostate surgical tissue samples were obtained from BPH patients undergoing TURP after taking informed consent. Ultrasound measure of prostatic weight and prostate-specific antigen (PSA) levels were obtained from the patients along with other clinical and demographic details. Tissue samples were fixed, processed, sectioned and stained with hematoxylin and eosin and Masson's trichrome to look for histological features, specifically smooth muscle proliferation. Immunohistochemical expression of bone morphogenetic protein (BMP)-2 was recorded to assess the calcification potential.

RESULTS

Fifty-nine surgical samples were obtained from the patients of age range 50-90 years and body mass index (BMI) 15.6-33.3 kg/m² . The range of ultrasound measures of prostate weight was 20-137 g with PSA ranged 1.03-93.3 ng/mL. Patients with small-sized prostate had significant severe smooth muscle proliferation (P < .001). Prostate size/weight had significant positive association with BMI (P < 0.001, r = 0.543) and negative association with BMP-2 (P < 0.001, r = -0.654). Samples with severe smooth muscle proliferation were with increased BMP-2 expression (P < .001) and higher levels of PSA levels (P = 0.004). BMP-2 expression revealed positive significant association with PSA (P < .001, r = 0.432).

CONCLUSION

From this study we conclude that BPH patients with small-sized glands and high PSA levels have increased smooth muscle proliferation and calcification potential causing the symptoms of lower urinary tract symptoms in these patients.

LSD1 downregulates p21 expression in vascular smooth muscle cells and promotes neointima formation

Neointima formation is characterized by the proliferation of vascular smooth muscle cells (VSMC). Although lysine-specific demethylase 1 (LSD1) has critical functions in several diseases, its role in neointima formation remains to be clarified. In this study, we aimed to explore the crucial role of LSD1 on neointima formation using a carotid artery injury model in mice. We observed that aberrant LSD1 expression was increased in human and mouse stenotic arteries and platelet-derived growth factor-BB (PDGF-BB)-treated VSMC. Furthermore, LSD1 knockdown significantly mitigated neointima formation in vivo and inhibited PDGF-BB-induced VSMC proliferation in vitro. We further uncovered that LSD1 overexpression exhibited opposite phenotypes in vivo and in vitro. Finally, LSD1 knockdown inhibited VSMC proliferation by increasing p21 expression, which is associated with LSD1 mediated di-methylated histone H3 on lysine 4 (H3K4me2) modification. Taken together, our data suggest that LSD1 may be a potential therapeutic target for the treatment of neointima formation.

The Effects of Acute and Chronic Selective Phosphodiesterase 1 Inhibition on Smooth Muscle Cell-Associated Aging Features

Age-related cardiovascular diseases (CVDs) remain among the leading global causes of death, and vascular smooth muscle cell (VSMC) remodeling plays an essential role in its pathology. Reduced NO-cGMP pathway signaling is a major feature and pathogenic mechanism underlying vasodilator dysfunction. Recently, we identified phosphodiesterase (PDE) 1, an enzyme that hydrolyzes and inactivates the cyclic nucleotides cAMP and cGMP, and thereby provides a potential treatment target for restoring age-related vascular dysfunction due to aging of VSMC. Based on this hypothesis, we here tested the effects of PDE1 inhibition in a model of SMC-specific accelerated aging mice. SMC-KO and their WT littermates received either vehicle or the PDE1 inhibitor lenrispodun for 8 weeks. Vascular function was measured both in vivo (Laser Doppler technique) and ex vivo (organ bath). Moreover, we deployed UV irradiation in cell culture experiments to model accelerated aging in an in vitro situation. SMC-KO mice display a pronounced loss of vasodilator function in the isolated aorta, the cutaneous microvasculature, and mesenteric arteries. Ex vivo, in isolated vascular tissue, we found that PDE1 inhibition with lenrispodun improves vasodilation, while no improvement was observed in isolated aorta taken from mice after chronic treatment in vivo. However, during lenrispodun treatment in vivo, an enhanced microvascular response in association with upregulated cGMP levels was seen. Further, chronic lenrispodun treatment decreased TNF-α and IL-10 plasma levels while the elevated level of IL-6 in SMC-KO mice remained unchanged after treatment. PDE1 and senescence markers, p16 and p21, were increased in both SMC-KO aorta and cultured human VSMC in which DNA was damaged by ultraviolet irradiation. This increase was lowered by chronic lenrispodun. In contrast, lenrispodun increased the level of PDE1A in both situations. In conclusion, we demonstrated that PDE1 inhibition may be therapeutically useful in reversing aspects of age-related VSMC dysfunction by potentiating NO-cGMP signaling, preserving microvascular function, and decreasing senescence. Yet, after chronic treatment, the effects of PDE1 inhibition might be counteracted by the interplay between differential PDE1A and C expression. These results warrant further pharmacodynamic profiling of PDE enzyme regulation during chronic PDE1 inhibitor treatment.

AFM Stiffness Mapping in Human Aortic Smooth Muscle Cells

Aortic Smooth Muscle Cells (SMCs) play a vital role in maintaining mechanical homeostasis in the aorta. We recently found that SMCs of aneurysmal aortas apply larger traction forces than SMCs of healthy aortas. This result was explained by the significant increase of hypertrophic SMCs abundance in aneurysms. In the present study, we investigate whether the cytoskeleton stiffness of SMCs may also be altered in aneurysmal aortas. For that, we use Atomic Force Microscopy (AFM) nanoindentation with a specific mode that allows subcellular-resolution mapping of the local stiffness across a specified region of interest of the cell. Aortic SMCs from a commercial human lineage (AoSMCs, Lonza) and primary aneurysmal SMCs (AnevSMCs) are cultured in conditions promoting the development of their contractile apparatus, and seeded on hydrogels with stiffness properties of 12kPa and 25kPa. Results show that all SMC exhibit globally a lognormal stiffness distribution, with medians in the range 10-30 kPa. The mean of stiffness distributions is slightly higher in aneurysmal SMCs than in healthy cells (16 kPa versus 12 kPa) but the differences are not statistically significant due to the large dispersion of AFM nanoindentation stiffness. We conclude that the possible alterations previously found in aneurysmal SMCs do not affect significantly the AFM nanoindentation stiffness of their cytoskeleton.

Improved Quantification of Cell Density in the Arterial Wall-A Novel Nucleus Splitting Approach Applied to 3D Two-Photon Laser-Scanning Microscopy

Accurate information on vascular smooth muscle cell (VSMC) content, orientation, and distribution in blood vessels is indispensable to increase understanding of arterial remodeling and to improve modeling of vascular biomechanics. We have previously proposed an analysis method to automatically characterize VSMC orientation and transmural distribution in murine carotid arteries under well-controlled biomechanical conditions. However, coincident nuclei, erroneously detected as one large nucleus, were excluded from the analysis, hampering accurate VSMC content characterization and distorting transmural distributions. In the present study, therefore, we aim to (1) improve the previous method by adding a "nucleus splitting" procedure to split coinciding nuclei, (2) evaluate the accuracy of this novel method, and (3) test this method in a mouse model of VSMC apoptosis. After euthanasia, carotid arteries from SM22α-hDTR Apoe -/- and control Apoe -/- mice were bluntly dissected, excised, mounted in a biaxial biomechanical tester and brought to in vivo axial stretch and a pressure of 100 mmHg. Nuclei and elastin fibers were then stained using Syto-41 and Eosin-Y, respectively, and imaged using 3D two-photon laser scanning microscopy. Nuclei were segmented from images and coincident nuclei were split. The nucleus splitting procedure determines the likelihood that voxel pairs within coincident nuclei belong to the same nucleus and utilizes these likelihoods to identify individual nuclei using spectral clustering. Manual nucleus counts were used as a reference to assess the performance of our splitting procedure. Before and after splitting, automatic nucleus counts differed -26.6 ± 9.90% (p < 0.001) and -1.44 ± 7.05% (p = 0.467) from the manual reference, respectively. Whereas the slope of the relative difference between the manual and automated counts as a function of the manual count was significantly negative before splitting (p = 0.008), this slope became insignificant after splitting (p = 0.653). Smooth muscle apoptosis led to a 33.7% decrease in VSMC density (p = 0.008). Nucleus splitting improves the accuracy of automated cell content quantification in murine carotid arteries and overcomes the progressively worsening problem of coincident nuclei with increasing cell content in vessels. The presented image analysis framework provides a robust tool to quantify cell content, orientation, shape, and distribution in vessels to inform experimental and advanced computational studies on vascular structure and function.

Differential Effects of Platelet Factor 4 (CXCL4) and Its Non-Allelic Variant (CXCL4L1) on Cultured Human Vascular Smooth Muscle Cells

Platelet factor 4 (CXCL4) is a chemokine abundantly stored in platelets. Upon injury and during atherosclerosis, CXCL4 is transported through the vessel wall where it modulates the function of vascular smooth muscle cells (VSMCs) by affecting proliferation, migration, gene expression and cytokine release. Variant CXCL4L1 is distinct from CXCL4 in function and expression pattern, despite a minor three-amino acid difference. Here, the effects of CXCL4 and CXCL4L1 on the phenotype and function of human VSMCs were compared in vitro. VSMCs were found to constitutively express CXCL4L1 and only exogenously added CXCL4 was internalized by VSMCs. Pre-treatment with heparin completely blocked CXCL4 uptake. A role of the putative CXCL4 receptors CXCR3 and DARC in endocytosis was excluded, but LDL receptor family members appeared to be involved in the uptake of CXCL4. Incubation of VSMCs with both CXCL4 and CXCL4L1 resulted in decreased expression of contractile marker genes and increased mRNA levels of KLF4 and NLRP3 transcription factors, yet only CXCL4 stimulated proliferation and calcification of VSMCs. In conclusion, CXCL4 and CXCL4L1 both modulate gene expression, yet only CXCL4 increases the division rate and formation of calcium-phosphate crystals in VSMCs. CXCL4 and CXCL4L1 may play distinct roles during vascular remodeling in which CXCL4 induces proliferation and calcification while endogenously expressed CXCL4L1 governs cellular homeostasis. The latter notion remains a subject for future investigation.

[Gly14]-Humanin inhibits an angiotensin II-induced vascular smooth muscle cell phenotypic switch via ameliorating intracellular oxidative stress

Angiotensin II (AngII) is involved in the pathogenesis of hypertensive artery remodeling by inducing a phenotypic switch in vascular smooth muscle cells [Gly14]-Humanin (HNG), a humanin analogue, exerts potent cytoprotective effects both in vitro and in vivo. This study aimed to investigate the effects of HNG on an AngII-induced phenotypic switch in VSMCs and the potential mechanisms underlying these effects. The roles of [Gly14]-Humanin in AngII-stimulated VSMCs proliferation and migration was detected by CCK-8 assay, Cell cycle analysis, wound healing assay, trsnswell assay and western blot. The mechanism by which [Gly14]-Humanin regulates VSMC phenotypic switch was determined by intracellular oxidative stress detection, transcriptomic analysis and qRT-PCR. The results showed that HNG inhibited AngII-induced VSMC proliferation and migration and maintained a stable VSMC contractile phenotype. In addition, HNG reduced the level of AngII-induced oxidative stress in vascular smooth muscle cells. This process could be accomplished by inhibiting nicotinamide adenine dinucleotide phosphate oxidase activity. In conclusion, the results suggested that HNG ameliorated intracellular oxidative stress by inhibiting NAD(P)H oxidase activity, thereby suppressing the AngII-induced VSMC phenotype switch. Thus, HNG is a potential drug to ameliorate artery remodeling in hypertension.