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Vascular aging influences hemodynamics, elevating risks for vascular diseases and dementia. We recently demonstrated that knockout (KO) of Dusp5 enhances cerebral and renal hemodynamics and cognitive function. This improvement correlates with elevated pPKC and pERK1/2 levels in the brain and kidneys. Additionally, we observed that Dusp5 KO modulates the passive mechanical properties of cerebral and renal arterioles, associated with increased myogenic tone at low pressure, enhanced distensibility, greater compliance, and reduced stiffness. The present study evaluates the structural and mechanical properties of the middle cerebral artery (MCA) in Dusp5 KO rats. We found that vascular smooth muscle cell layers and the collagen content in the MCA wall are comparable between Dusp5 KO and control rats. The internal elastic lamina in the MCA of Dusp5 KO rats exhibits increased thickness, higher autofluorescence intensity, smaller fenestrae areas, and fewer fenestrations. Despite an enhanced myogenic response and tone of the MCA in Dusp5 KO rats, other passive mechanical properties, such as wall thickness, cross-sectional area, wall-to-lumen ratio, distensibility, incremental elasticity, circumferential wall stress, and elastic modulus, do not significantly differ between strains. These findings suggest that while Dusp5 KO has a limited impact on altering the structural and mechanical properties of MCA, its primary role in ameliorating hemodynamics and cognitive functions is likely attributable to its enzymatic activity on cerebral arterioles. Further research is needed to elucidate the specific enzymatic mechanisms and explore potential clinical applications in the context of vascular aging. [ABSTRACT FROM AUTHOR]

Vascular lesions frequently arise as complication in patients diagnosed with diabetes mellitus (DM). Presently, percutaneous coronary intervention (PCI) and antithrombotic therapy serve as primary treatments. However, in-stent restenosis persists as a challenging clinical issue following PCI, lacking sustained and effective treatment. Linarin (LN) exhibits diverse pharmacological activities and is regarded as a potential drug for treating various diseases, including DM. But its specific role in restenosis after vascular injury in DM patients remains unclear. A rat model of diabetes-related restenosis was established to evaluate the role of LN on neointimal hyperplasia. Vascular smooth muscle cells (VSMCs) stimulated by high glucose (HG, 30 mM) underwent LN treatment. Additionally, an overexpression plasmid of A disintegrin and metalloproteinases (ADAM10) was constructed to transfect VSMCs. We employed CCK-8, Brdu, wound-healing scratch, and transwell migration assays to evaluate the proliferation and migration of VSMCs. Furthermore, western blot and immunofluorescence assays were utilized to investigate the expressions of ADAM10 and the downstream Notch signaling pathway in vivo and in vitro models. LN notably alleviated intimal hyperplasia after vascular injury in DM rats and reduced the protein expression of ADAM10, alongside its downstream Notch1 signaling pathway-related proteins (Notch1, NICD and Hes1) in rat carotid artery tissues. LN effectively suppressed the proliferation and migration of VSMCs induced by HG, downregulating the protein expression of ADAM10, Notch1, NICD and Hes1. Moreover, our findings indicated that ADAM10 overexpression significantly reversed LN's effects on proliferation, migration, and the expression of Notch1 signaling pathway-related proteins in HG-treated VSMCs. LN demonstrates potential therapeutic efficacy in addressing restenosis after diabetic-related vascular injury, with the ADAM10 mediated Notch signaling pathway playing a pivotal role. [ABSTRACT FROM AUTHOR]

Arterial stiffening is a critical risk factor contributing to the exponential rise in age‐associated cardiovascular disease incidence. This process involves age‐induced arterial proinflammation, collagen deposition, and calcification, which collectively contribute to arterial stiffening. The primary driver of proinflammatory processes leading to collagen deposition in the arterial wall is the transforming growth factor‐beta1 (TGF‐β1) signaling. Activation of this signaling is pivotal in driving vascular extracellular remodeling, eventually leading to arterial fibrosis and calcification. Interestingly, the glycosylated protein vasorin (VASN) physically interacts with TGF‐β1, and functionally restraining its proinflammatory fibrotic signaling in arterial walls and vascular smooth muscle cells (VSMCs). Notably, as age advances, matrix metalloproteinase type II (MMP‐2) is activated, which effectively cleaves VASN protein in both arterial walls and VSMCs. This age‐associated/MMP‐2‐mediated decrease in VASN levels exacerbates TGF‐β1 activation, amplifying arterial fibrosis and calcification in the arterial wall. Importantly, TGF‐β1 is a downstream molecule of the angiotensin II (Ang II) signaling pathway in the arterial wall and VSMCs, which is modulated by VASN. Indeed, chronic administration of Ang II to young rats significantly activates MMP‐2 and diminishes the VASN expression to levels comparable to untreated older control rats. This review highlights and discusses the role played by VASN in mitigating fibrosis and calcification by alleviating TGF‐β1 activation and signaling in arterial walls and VSMCs. Understanding these molecular physical and functional interactions may pave the way for establishing VASN‐based therapeutic strategies to counteract adverse age‐associated cardiovascular remodeling, eventually reducing the risk of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Arterial media calcification or pathological deposition of calcium-phosphate crystals in the vessel wall contributes significantly to the high mortality rate observed in patients with CKD. Extracellular nucleotides (ie, ATP or UTP) regulate the arterial calcification process by interacting with (1) purinergic receptors and (2) breakdown via ecto-nucleotidases, such as ectonucleotide pyrophosphatase/phosphodiesterase NPP1 or NPP3, affecting the local levels of calcification inhibitor, pyrophosphate, and stimulator inorganic phosphate (PPi/Pi ratio). Also, it has been shown that ATP analogs (ie, β,γ-methylene-ATP [β,γ-meATP]) inhibit vascular smooth muscle cell calcification in vitro. In the first experiment, daily dosing of β,γ-meATP (2 mg/kg) was investigated in rats fed a warfarin diet to trigger the development of non–CKD-related arterial medial calcifications. This study showed that β,γ-meATP significantly lowered the calcium scores in the aorta and peripheral vessels in warfarin-exposed rats. In a second experiment, daily dosing of 4 mg/kg β,γ-meATP and its metabolite medronic acid (MDP) was analyzed in rats fed an adenine diet to promote the development of CKD-related arterial medial calcification. Administration of β,γ-meATP and MDP did not significantly decrease aortic calcification scores in this model. Moreover, both compounds induced deleterious effects on physiological bone mineralization, causing an imminent risk for worsening the already compromised bone status in CKD. Due to this, it was not possible to raise the dosage of both compounds to tackle CKD-related arterial calcification. Again, this points out the difficult task of targeting solely ectopic calcifications without negatively affecting physiological bone mineralization. On the other hand, aortic mRNA expression of Enpp1 and Enpp3 was significantly and positively associated with aortic calcification scores, suggesting that normalizing the aortic NPP1/3 activity to control values might be a possible target to treat (CKD-induced) arterial media calcifications. [ABSTRACT FROM AUTHOR]

Background and Objectives: Endocan, secreted from the activated endothelium, is a key player in inflammation, endothelial dysfunction, proliferation of vascular smooth muscle cells, and angiogenesis. We aimed to investigate the link between endocan and aortic stiffness in maintenance hemodialysis (HD) patients. Materials and Methods: After recruiting HD patients from a medical center, their baseline characteristics, blood sample, and anthropometry were assessed and recorded. The serum endocan level was determined using an enzyme immunoassay kit, and carotid–femoral pulse wave velocity (cfPWV) measurement was used to evaluate aortic stiffness. Results: A total of 122 HD patients were enrolled. Aortic stiffness was diagnosed in 53 patients (43.4%), who were found to be older (p = 0.007) and have a higher prevalence of diabetes (p < 0.001) and hypertension (p = 0.030), higher systolic blood pressure (p = 0.011), and higher endocan levels (p < 0.001), when compared with their counterparts. On the multivariate logistic regression model, the development of aortic stiffness in patients on chronic HD was found to be associated with endocan [odds ratio (OR): 1.566, 95% confidence interval (CI): 1.224–2.002, p < 0.001], age (OR: 1.040, 95% CI: 1.001–1.080, p = 0.045), and diabetes (OR: 4.067, 95% CI: 1.532–10.798, p = 0.005), after proper adjustment for confounders (adopting diabetes, hypertension, age, systolic blood pressure, and endocan). The area under the receiver operating characteristic curve was 0.713 (95% CI: 0.620–0.806, p < 0.001) for predicting aortic stiffness by the serum endocan level, at an optimal cutoff value of 2.68 ng/mL (64.15% sensitivity, 69.57% specificity). Upon multivariate linear regression analysis, logarithmically transformed endocan was proven as an independent predictor of cfPWV (β = 0.405, adjusted R2 change = 0.152; p < 0.001). Conclusions: The serum endocan level positively correlated with cfPWV and was an independent predictor of aortic stiffness in chronic HD patients. [ABSTRACT FROM AUTHOR]

An increase in the delivery and use of oxygen to the musculature in physically active subjects are determinants of improving health-related aerobic capacity. Additional health benefits, such as an increase in the muscle mass and a decrease in fat mass, principally in the legs, could be achieved with weekly global physical activity levels of more than 300 min. The objective was to compare the muscle vascular and metabolic profiles of physically very active and inactive subjects. Twenty healthy men participated in the study; ten were assigned to the physically very active group (25.5 ± 4.2 years; 72.7 ± 8.1 kg; 173.7 ± 7.6 cm) and ten to the physically inactive group (30.0 ± 7.4 years; 74.9 ± 11.8 kg; 173.0 ± 6.4 cm). The level of physical activity was determined by the Global Physical Activity Questionnaire (GPAQ). A resting vascular occlusion test (5 min of an ischemic phase and 3 min of a reperfusion phase) was used, whereas a near-field infrared spectroscopy (NIRS) device was used to evaluate the muscle oxygenation in the right vastus lateralis of the quadriceps muscle. The area under the curve of the deoxyhemoglobin (HHb) during the ischemic phase and above the curve of the tissue saturation index (TSI) during the reperfusion phase were obtained to determine muscle metabolic and vascular responses, respectively. Physically very active group showed a higher absolute HHb (3331.9 ± 995.7 vs. 6182.7 ± 1632.5 mmol/s) and lower TSI (7615.0 ± 1111.9 vs. 5420.0 ± 781.4 %/s) and relative to body weight (46.3 ± 14.6 vs. 84.4 ± 27.1 mmol/s/kg and 106.0 ± 20.6 vs. 73.6 ± 13.8 %/s/kg, respectively), muscle mass (369.9 ± 122.2 vs. 707.5 ± 225.8 mmol/kg and 829.7 ± 163.4 vs. 611.9 ± 154.2 %/s/kg) and fat mass (1760.8 ± 522.9 vs. 2981.0 ± 1239.9 mmol/s/kg and 4160.0 ± 1257.3 vs. ±2638.4 ± 994.3 %/s/kg, respectively) than physically inactive subjects. A negative correlation was observed between HHb levels and TSI (r = −0.6; p < 0.05). Physically very active men (>300 min/week) present better muscle oxidative metabolism and perfusion and perform significantly more physical activity than physically inactive subjects. Extra benefits for vascular health and muscle oxidative metabolism are achieved when a subject becomes physically very active, as recommended by the World Health Organization. In addition, a higher level of physical activity determined by GPAQ is related to better vascular function and oxidative metabolism of the main locomotor musculature, i.e., the quadriceps. [ABSTRACT FROM AUTHOR]

The document is a corrigendum for an article on the protective effects of inhibiting mitochondrial fission on organ function after sepsis. It acknowledges errors in Figures 2 and 3 of the original publication, where images were misused and confirms that these errors do not impact the scientific conclusions of the study. The corrected figures show the effects of Mdivi-1 on vital organ function and mitochondrial morphology in septic rats. The study was conducted by researchers from the State Key Laboratory of Trauma, Burns, and Combined Injury in Chongqing, China. [Extracted from the article]

This article discusses the historical underrepresentation of females in biomedical research and the resulting gap in our understanding of cardiovascular physiology in women. It specifically focuses on the effect of hormonal cycles on vascular physiology in premenopausal females. The article highlights the need for further research in this area to expand our knowledge of female physiology and identify situations where control practices are necessary in research design. The study mentioned in the article found minimal effects of hormonal phases on vascular function in women, but suggests that the hormonal environment may influence microvascular function. The article concludes by discussing the importance of appropriate statistical considerations and future directions for research in this field. [Extracted from the article]

The article discusses the connection between Piezo1 channels and BK channels in vascular smooth muscle cells. Piezo1 channels are non-selective Ca2+-permeable channels that are highly expressed in the vascular system and play a role in sensing hemodynamic forces and mediating endothelial responses to blood flow. The study found that the activation of Piezo1 channels leads to the relaxation of vascular smooth muscle cells through the activation of BK channels. The researchers also observed that in type II diabetic mice, the expression of Piezo1 in endothelial cells is reduced, resulting in a smaller relaxation response. However, in endothelium-denuded arteries from diabetic mice, the activation of BK channels by Piezo1 is enhanced, leading to a more effective relaxation response. The study suggests that the regulation of the functional coupling between Piezo1 and BK channels may have implications for the pathophysiology of diabetes. Further research is needed to understand the precise mechanisms of this coupling. [Extracted from the article]

Gould syndrome is a rare multisystem disorder resulting from autosomal dominant mutations in the collagen-encoding genes COL4A1 and COL4A2. Human patients and Col4a1 mutant mice display brain pathology that typifies cerebral small vessel diseases (cSVDs), including white matter hyperintensities, dilated perivascular spaces, lacunar infarcts, microbleeds, and spontaneous intracerebral hemorrhage. The underlying pathogenic mechanisms are unknown. Using the Col4a1+/G394V mouse model, we found that vasoconstriction in response to internal pressure-the vascular myogenic response-is blunted in cerebral arteries from middle-aged (12 mo old) but not young adult (3 mo old) animals, revealing age-dependent cerebral vascular dysfunction. The defect in the myogenic response was associated with a significant decrease in depolarizing cation currents conducted by TRPM4 (transient receptor potential melastatin 4) channels in native cerebral artery smooth muscle cells (SMCs) isolated from mutant mice. The minor membrane phospholipid phosphatidylinositol 4,5 bisphosphate (PIP2) is necessary for TRPM4 activity. Dialyzing SMCs with PIP2 and selective blockade of phosphoinositide 3-kinase (PI3K), an enzyme that converts PIP2 to phosphatidylinositol (3, 4, 5)-trisphosphate (PIP3), restored TRPM4 currents. Acute inhibition of PI3K activity and blockade of transforming growth factor-beta (TGF-β) receptors also rescued the myogenic response, suggesting that hyperactivity of TGF-β signaling pathways stimulates PI3K to deplete PIP2 and impair TRPM4 channels. We conclude that age-related cerebral vascular dysfunction in Col4a1+/G394V mice is caused by the loss of depolarizing TRPM4 currents due to PIP2 depletion, revealing an age-dependent mechanism of cSVD.

Aortic aneurysms (AA) and aorta dissection (AD) are life-threatening conditions with a rising incidence and high mortality rate. Recent research has linked non-coding RNAs to the regulation of AA and AD progression. In this study, we performed circRNA sequencing, microRNA (miRNA) sequencing, and messenger RNA (mRNA) sequencing on plasma samples from AA and AD patients to identify the key circRNA-miRNA-mRNA axis involved in the transition from AA to AD. Our results showed elevated levels of circ_0000006 and circ_0000160, along with decreased levels of hsa-let-7e-5p in AD samples compared to AA samples. Predictive analysis suggested that circ_0000006 and circ_0000160 potentially target hsa-let-7e-5p, which in turn may bind to the mRNA of Ubiquilin 4 (UBQLN4). In an AD cell model using vascular smooth muscle cells (VSMCs), silencing circ_0000006 and circ_0000160 attenuated the effects of platelet-derived growth factor (PDGF)-induced phenotypic changes, proliferation, and migration. This effect was partially reversed by inhibiting hsa-let-7e-5p. Furthermore, we found that overexpression of UBQLN4 counteracted the effects of hsa-let-7e-5p, suggesting UBQLN4 as a downstream mediator of hsa-let-7e-5p. In an animal model of AD, knockdown of circ_0000006 and circ_0000160 also showed protective effects against aortic septation. Overall, our findings indicate that the upregulation of circ_0000006 and circ_0000160 contributes to the progression from AA to AD by influencing abnormal phenotypic changes, migration, and proliferation of VSMCs. The Hsa-let-7e-5p/UBQLN4 axis may play a critical role in AD development. Targeting circ_0000006 and circ_0000160 could be a potential therapeutic strategy for preventing the progression of AD. [ABSTRACT FROM AUTHOR]

Background: Vascular calcification (VC) is an independent risk factor for cardiovascular diseases. Recently, ferroptosis has been recognised as a novel therapeutic target for cardiovascular diseases. Although an association between ferroptosis and vascular calcification has been reported, the role and mechanism of iron overload in vascular calcification are still poorly understood. Specifically, further in-depth research is required on whether metalloproteins SLC39a14 and SLC39a8 are involved in ferroptosis induced by iron overload. Methods: R language was employed for the differential analysis of the dataset, revealing the correlation between ferroptosis and calcification. The experimental approaches encompassed both in vitro and in vivo studies, incorporating the use of iron chelators and models of iron overload. Additionally, gain- and loss-of-function experiments were conducted to investigate iron's effects on vascular calcification comprehensively. Electron microscopy, immunofluorescence, western blotting, and real-time polymerase chain reaction were used to elucidate how Slc39a14 and Slc39a8 mediate iron overload and promote calcification. Results: Ferroptosis was observed in conjunction with vascular calcification (VC); the association was consistently confirmed by in vitro and in vivo studies. Our results showed a positive correlation between iron overload in VSMCs and calcification. Iron chelators are effective in reversing VC and iron overload exacerbates this process. The expression levels of the metal transport proteins Slc39a14 and Slc39a8 were significantly upregulated during calcification; the inhibition of their expression alleviated VC. Conversely, Slc39a14 overexpression exacerbates calcification and promotes intracellular iron accumulation in VSMCs. Conclusions: Our research demonstrates that iron overload occurs during VC, and that inhibition of Slc39a14 and Slc39a8 significantly relieves VC by intercepting iron overload-induced ferroptosis in VSMCs, providing new insights into the VC treatment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Vascular calcification, which is characterized by calcium deposition in arterial walls and the osteochondrogenic differentiation of vascular smooth muscle cells, is an actively regulated process that involves complex mechanisms. Vascular calcification is associated with increased cardiovascular adverse events. The role of 4-hydroxynonenal (4-HNE), which is the most abundant stable product of lipid peroxidation, in vascular calcification has been poorly investigated. METHODS: Serum was collected from patients with chronic kidney disease and controls, and the levels of 4-HNE and 8-isoprostaglandin F2α were measured. Sections of coronary atherosclerotic plaques from donors were immunostained to analyze calcium deposition and 4-HNE. A total of 658 patients with coronary artery disease who received coronary computed tomography angiography were recruited to analyze the relationship between coronary calcification and the rs671 mutation in aldehyde dehydrogenase 2 (ALDH2). ALDH2 knockout (ALDH2-/-) mice, smooth muscle cell--specific ALDH2 knockout mice, ALDH2 transgenic mice, and their controls were used to establish vascular calcification models. Primary mouse aortic smooth muscle cells and human aortic smooth muscle cells were exposed to medium containing β-glycerophosphate and CaCl2 to investigate cell calcification and the underlying molecular mechanisms. RESULTS: Elevated 4-HNE levels were observed in the serum of patients with chronic kidney disease and model mice and were detected in calcified artery sections by immunostaining. ALDH2 knockout or smooth muscle cell--specific ALDH2 knockout accelerated the development of vascular calcification in model mice, whereas overexpression or activation prevented mouse vascular calcification and the osteochondrogenic differentiation of vascular smooth muscle cells. In patients with coronary artery disease, patients with ALDH2 rs671 gene mutation developed more severe coronary calcification. 4-HNE promoted calcification of both mouse aortic smooth muscle cells and human aortic smooth muscle cells and their osteochondrogenic differentiation in vitro. 4-HNE increased the level of Runx2 (runt-related transcription factor-2), and the effect of 4-HNE on promoting vascular smooth muscle cell calcification was ablated when Runx2 was knocked down. Mutation of Runx2 at lysine 176 reduced its carbonylation and eliminated the 4-HNE--induced upregulation of Runx2. CONCLUSIONS: Our results suggest that 4-HNE increases Runx2 stabilization by directly carbonylating its K176 site and promotes vascular calcification. ALDH2 might be a potential target for the treatment of vascular calcification. [ABSTRACT FROM AUTHOR]

Introduction: IL-2Rα knock out (KO) mice have been instrumental to discovering the immunoregulatory properties of IL-2Rα. While initially thought of only as a stimulatory cytokine, IL-2 and IL-2Rα KO mice revealed that this cytokine-receptor system controls immune responses through restimulation-induced cell death and by promoting the survival of T regulatory cells. Although described mostly in the context of lymphocytes, recent studies by our laboratory showed that IL-2R is expressed in smooth muscle cells. Given this finding, we sought to use IL-2Rα KO to determine the function of this receptor in vascular smooth muscle cells. Surprisingly, we found that IL-2Rα KO vascular smooth muscle cells had detectable IL-2Rα. Methods: We used multiple gene and protein-based methods to determine why IL-2Rα KO vascular smooth muscle cells exhibited IL-2Rα protein. These methods included: genomic sequencing, assessing cells and tissues for evidence of maternal microchimerism, and determining the half-life of IL-2Rα protein. Results: Our studies demonstrated the following: (1) in addition to the cell surface, IL-2Rα is localized to the nucleus; (2) the genetic deletion of IL-2Rα is intact in IL-2Rα KO mice; (3) both IL-2Rα KO and WT tissues show evidence of maternal microchimerism, the likely source of IL-2Rα (4) IL-2Rα is transmitted between cells; (5) IL-2Rα has a long half-life; and (6) nuclear IL-2Rα contributes to the regulation of cell proliferation and size. Conclusion: Our findings suggest that the phenotype of complete IL-2Rα loss is more severe than demonstrated by IL-2Rα KO mice, and that IL-2Rα plays a hereto-fore unrecognized role in regulating cell proliferation in non-lymphoid cells. [ABSTRACT FROM AUTHOR]

Aims Vascular smooth muscle cells (SMCs) and their derivatives are key contributors to the development of atherosclerosis. However, studying changes in SMC gene expression in heterogeneous vascular tissues is challenging due to the technical limitations and high cost associated with current approaches. In this paper, we apply translating ribosome affinity purification sequencing to profile SMC-specific gene expression directly from tissue. Methods and results To facilitate SMC-specific translatome analysis, we generated SMCTRAP mice, a transgenic mouse line expressing enhanced green fluorescent protein (EGFP)-tagged ribosomal protein L10a (EGFP-L10a) under the control of the SMC-specific αSMA promoter. These mice were further crossed with the atherosclerosis model Ldlr−/−, ApoB100/100 to generate SMCTRAP−AS mice and used to profile atherosclerosis-associated SMCs in thoracic aorta samples of 15-month-old SMCTRAP and SMCTRAP-AS mice. Our analysis of SMCTRAP-AS mice showed that EGFP-L10a expression was localized to SMCs in various tissues, including the aortic wall and plaque. The TRAP fraction demonstrated high enrichment of known SMC-specific genes, confirming the specificity of our approach. We identified several genes, including Cemip , Lum , Mfge8 , Spp1 , and Serpina3 , which are known to be involved in atherosclerosis-induced gene expression. Moreover, we identified several novel genes not previously linked to SMCs in atherosclerosis, such as Anxa4 , Cd276 , inter-alpha-trypsin inhibitor-4 (Itih4), Myof , Pcdh11x , Rab31 , Serpinb6b , Slc35e4 , Slc8a3 , and Spink5. Among them, we confirmed the SMC-specific expression of Itih4 in atherosclerotic lesions using immunofluorescence staining of mouse aortic roots and spatial transcriptomics of human carotid arteries. Furthermore, our more detailed analysis of Itih4 showed its link to coronary artery disease through the colocalization of genome-wide association studies, splice quantitative trait loci (QTL), and protein QTL signals. Conclusion We generated a SMC-specific TRAP mouse line to study atherosclerosis and identified Itih4 as a novel SMC-expressed gene in atherosclerotic plaques, warranting further investigation of its putative function in extracellular matrix stability and genetic evidence of causality. [ABSTRACT FROM AUTHOR]

Identifying alterations caused by aging could be an important tool for improving the diagnosis of cardiovascular diseases. Changes in vascular tone regulation involve various mechanisms, like NO synthase activity, activity of the sympathetic nervous system, production of prostaglandin, endothelium-dependent relaxing, and contracting factors, etc. Surprisingly, Ca2+-dependent Cl− channels (CaCCs) are involved in all alterations of the vascular tone regulation mentioned above. Furthermore, we discuss these mechanisms in the context of ontogenetic development and aging. The molecular and electrophysiological mechanisms of CaCCs activation on the cell membrane of the vascular smooth muscle cells (VSMC) and endothelium are explained, as well as the age-dependent changes that imply the activation or inhibition of CaCCs. In conclusion, due to the diverse intracellular concentration of chloride in VSMC and endothelial cells, the activation of CaCCs depends, in part, on intracellular Ca2+ concentration, and, in part, on voltage, leading to fine adjustments of vascular tone. The activation of CaCCs declines during ontogenetic development and aging. This decline in the activation of CaCCs involves a decrease in protein level, the impairment of Ca2+ influx, and probably other alterations in vascular tone regulation. [ABSTRACT FROM AUTHOR]

Background: The fusiform aneurysm is a nonsaccular dilatation affecting the entire vessel wall over a short distance. Although PDGFRB somatic variants have been identified in fusiform intracranial aneurysms, the molecular and cellular mechanisms driving fusiform intracranial aneurysms due to PDGFRB somatic variants remain poorly understood. Methods: In this study, single-cell sequencing and immunofluorescence were employed to investigate the phenotypic changes in smooth muscle cells within fusiform intracranial aneurysms. Whole-exome sequencing revealed the presence of PDGFRB gene mutations in fusiform intracranial aneurysms. Subsequent immunoprecipitation experiments further explored the functional alterations of these mutated PDGFRB proteins. For the common c.1684 mutation site of PDGFRβ, we established mutant smooth muscle cell lines and zebrafish models. These models allowed us to simulate the effects of PDGFRB mutations. We explored the major downstream cellular pathways affected by PDGFRBY562D mutations and evaluated the potential therapeutic effects of Ruxolitinib. Results: Single-cell sequencing of two fusiform intracranial aneurysms sample revealed downregulated smooth muscle cell markers and overexpression of inflammation-related markers in vascular smooth muscle cells, which was validated by immunofluorescence staining, indicating smooth muscle cell phenotype modulation is involved in fusiform aneurysm. Whole-exome sequencing was performed on seven intracranial aneurysms (six fusiform and one saccular) and PDGFRB somatic mutations were detected in four fusiform aneurysms. Laser microdissection and Sanger sequencing results indicated that the PDGFRB mutations were present in smooth muscle layer. For the c.1684 (chr5: 149505131) site mutation reported many times, further cell experiments showed that PDGFRBY562D mutations promoted inflammatory-related vascular smooth muscle cell phenotype and JAK-STAT pathway played a crucial role in the process. Notably, transfection of PDGFRBY562D in zebrafish embryos resulted in cerebral vascular anomalies. Ruxolitinib, the JAK inhibitor, could reversed the smooth muscle cells phenotype modulation in vitro and inhibit the vascular anomalies in zebrafish induced by PDGFRB mutation. Conclusion: Our findings suggested that PDGFRB somatic variants played a role in regulating smooth muscle cells phenotype modulation in fusiform aneurysms and offered a potential therapeutic option for fusiform aneurysms. [ABSTRACT FROM AUTHOR]

Hypertensive nephropathy (HN) is a prevalent complication of hypertension and stands as the second primary reason for end-stage renal disease. Research in clinical settings has revealed that Yanggan Yishui Granule (YGYSG) has significant therapeutic effects on HN. However, the material basis and action mechanisms of YGYSG against HN remain unclear. Consequently, this study utilized a comprehensive method integrating ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS), network pharmacology, and molecular docking to delineate the active ingredients and potential therapeutic mechanisms of YGYSG for treating HN. Firstly, sixty distinct components were recognized in total as potential active ingredients in YGYSG by UPLC-Q-TOF/MS. Subsequently, the mechanisms of YGYSG against HN were revealed for the first time using network pharmacology. 23 ingredients played key roles in the complete network and were the key active ingredients, which could affect the renin-angiotensin system, fluid shear stress and atherosclerosis, HIF-1 signaling pathway, and AGE-RAGE signaling pathway in diabetic complications by regulating 29 key targets such as TNF, IL6, ALB, EGFR, ACE, and MMP2. YGYSG could treat HN through the suppression of inflammatory response and oxidative stress, attenuating the proliferation of renal vascular smooth muscle cells, lessening glomerular capillary systolic pressure, and ameliorating renal dysfunction and vascular damage through the aforementioned targets and pathways. Molecular docking results revealed that most key active ingredients exhibited a high affinity for binding to the key targets. This study pioneers in clarifying the bioactive compounds and molecular mechanisms of YGYSG against HN and offers scientific reference into the clinical application. [ABSTRACT FROM AUTHOR]

Sigmar1 is a ubiquitously expressed, multifunctional protein known for its cardioprotective roles in cardiovascular diseases. While accumulating evidence indicate a critical role of Sigmar1 in cardiac biology, its physiological function in the vasculature remains unknown. In this study, we characterized the expression of Sigmar1 in the vascular wall and assessed its physiological function in the vascular system using global Sigmar1 knockout (Sigmar1-/-) mice. We determined the expression of Sigmar1 in the vascular tissue using immunostaining and biochemical experiments in both human and mouse blood vessels. Deletion of Sigmar1 globally in mice (Sigmar1-/-) led to blood vessel wall reorganizations characterized by nuclei disarray of vascular smooth muscle cells, altered organizations of elastic lamina, and higher collagen fibers deposition in and around the arteries compared to wildtype littermate controls (Wt). Vascular function was assessed in mice using non-invasive time-transit method of aortic stiffness measurement and flow-mediated dilation (FMD) of the left femoral artery. Sigmar1-/- mice showed a notable increase in arterial stiffness in the abdominal aorta and failed to increase the vessel diameter in response to reactive-hyperemia compared to Wt. This was consistent with reduced plasma and tissue nitric-oxide bioavailability (NOx) and decreased phosphorylation of endothelial nitric oxide synthase (eNOS) in the aorta of Sigmar1-/- mice. Ultrastructural analysis by transmission electron microscopy (TEM) of aorta sections showed accumulation of elongated shaped mitochondria in both vascular smooth muscle and endothelial cells of Sigmar1-/- mice. In accordance, decreased mitochondrial respirometry parameters were found in ex-vivo aortic rings from Sigmar1 deficient mice compared to Wt controls. These data indicate a potential role of Sigmar1 in maintaining vascular homeostasis. [ABSTRACT FROM AUTHOR]

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of cardiovascular mortality and is increasingly prevalent in our population. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) can safely and effectively lower glucose levels while concurrently managing the full spectrum of ASCVD risk factors and improving patients' long-term prognosis. Several cardiovascular outcome trials (CVOTs) have been carried out to further investigate the cardiovascular benefits of GLP-1RAs. Analyzing data from CVOTs can provide insights into the pathophysiologic mechanisms by which GLP-1RAs are linked to ASCVD and define the use of GLP-1RAs in clinical practice. Here, we discussed various mechanisms hypothesized in previous animal and preclinical human studies, including blockade of the production of adhesion molecules and inflammatory factors, induction of endothelial cells' synthesis of nitric oxide, protection of mitochondrial function and restriction of oxidative stress, suppression of NOD-like receptor thermal protein domain associated protein three inflammasome, reduction of foam cell formation and macrophage inflammation, and amelioration of vascular smooth muscle cell dysfunction, to help explain the cardiovascular benefits of GLP-1RAs in CVOTs. This paper provides an overview of the clinical research, molecular processes, and possible therapeutic applications of GLP-1RAs in ASCVD, while also addressing current limitations in the literature and suggesting future research directions. [ABSTRACT FROM AUTHOR]

Thoracic aortic aneurysm (TAA) is a life-threatening vascular disease frequently associated with underlying genetic causes. An inadequate understanding of human TAA pathogenesis highlights the need for better disease models. Here, we established a functional human TAA model in an animal host by combining human induced pluripotent stem cells (hiPSCs), bioengineered vascular grafts (BVGs), and gene editing. We generated BVGs from isogenic control hiPSC-derived vascular smooth muscle cells (SMCs) and mutant SMCs gene-edited to carry a Loeys-Dietz syndrome (LDS)–associated pathogenic variant (TGFBR1A230T). We also generated hiPSC-derived BVGs using cells from a patient with LDS (PatientA230T/+) and using genetically corrected cells (Patient+/+). Control and experimental BVGs were then implanted into the common carotid arteries of nude rats. The TGFBR1A230T variant led to impaired mechanical properties of BVGs, resulting in lower burst pressure and suture retention strength. BVGs carrying the variant dilated over time in vivo, resembling human TAA formation. Spatial transcriptomics profiling revealed defective expression of extracellular matrix (ECM) formation genes in PatientA230T/+ BVGs compared with Patient+/+ BVGs. Histological analysis and protein assays validated quantitative and qualitative ECM defects in PatientA230T/+ BVGs and patient tissue, including decreased collagen hydroxylation. SMC organization was also impaired in PatientA230T/+ BVGs as confirmed by vascular contraction testing. Silencing of collagen-modifying enzymes with small interfering RNAs reduced collagen proline hydroxylation in SMC-derived tissue constructs. These studies demonstrated the utility of BVGs to model human TAA formation in an animal host and highlighted the role of reduced collagen modifying enzyme activity in human TAA formation. Editor's summary: Thoracic aortic aneurysms (TAAs) form in patients with Loeys-Dietz syndrome (LDS), but in vivo models that recapitulate the pathophysiological features of early human disease are limited. Here, Yang and colleagues generated bioengineered vascular grafts using vascular smooth muscle cells (SMCs) derived from human induced pluripotent stem cells and implanted them into the common carotid arteries of nude rats to model TAA. Grafts seeded with cells containing a pathogenic variant in TGFBR1, which causes LDS, were shown to dilate in the face of strain caused by blood flow, and the authors found lower expression of collagen-related genes and impaired prolyl hydroxylase activity in uncorrected LDS grafts, suggesting that specific deficiencies in the extracellular matrix contribute to TAA formation in this disease. —Melissa L. Norton [ABSTRACT FROM AUTHOR]

Piezo1 and Piezo2 are recently reported mechanosensory ion channels that transduce mechanical stimuli from the environment into intracellular biochemical signals in various tissues and organ systems. Here, we show that Piezo1 and Piezo2 display a robust expression during jawbone development. Deletion of Piezo1 in neural crest cells causes jawbone malformations in a small but significant number of mice. We further demonstrate that disruption of Piezo1 and Piezo2 in neural crest cells causes more striking defects in jawbone development than any single knockout, suggesting essential but partially redundant roles of Piezo1 and Piezo2. In addition, we observe defects in other neural crest derivatives such as malformation of the vascular smooth muscle in double knockout mice. Moreover, TUNEL examinations reveal excessive cell death in osteogenic cells of the maxillary and mandibular arches of the double knockout mice, suggesting that Piezo1 and Piezo2 together regulate cell survival during jawbone development. We further demonstrate that Yoda1, a Piezo1 agonist, promotes mineralization in the mandibular arches. Altogether, these data firmly establish that Piezo channels play important roles in regulating jawbone formation and maintenance. [ABSTRACT FROM AUTHOR]

Intimal hyperplasia is a complicated pathophysiological phenomenon attributable to in-stent restenosis, and the underlying mechanism remains unclear. Interleukin enhancer-binding factor 3 (ILF3), a double-stranded RNA-binding protein involved in regulating mRNA stability, has been recently demonstrated to assume a crucial role in cardiovascular disease; nevertheless, its impact on intimal hyperplasia remains unknown. In current study, we used samples of human restenotic arteries and rodent models of intimal hyperplasia, we found that vascular smooth muscle cell (VSMC) ILF3 expression was markedly elevated in human restenotic arteries and murine ligated carotid arteries. SMC-specific ILF3 knockout mice significantly suppressed injury induced neointimal formation. In vitro, platelet-derived growth factor type BB (PDGF-BB) treatment elevated the level of VSMC ILF3 in a dose- and time-dependent manner. ILF3 silencing markedly inhibited PDGF-BB-induced phenotype switching, proliferation, and migration in VSMCs. Transcriptome sequencing and RNA immunoprecipitation sequencing depicted that ILF3 maintained its stability upon binding to the mRNA of the high-mobility group box 1 protein (HMGB1), thereby exerting an inhibitory effect on the transcription of dual specificity phosphatase 16 (DUSP16) through enhanced phosphorylation of signal transducer and activator of transcription 3 (STAT3). Therefore, the results both in vitro and in vivo indicated that the loss of ILF3 in VSMC ameliorated neointimal hyperplasia by regulating the STAT3/DUSP16 axis through the degradation of HMGB1 mRNA. Our findings revealed that vascular injury activates VSMC ILF3, which in turn promotes intima formation. Consequently, targeting specific VSMC ILF3 may present a potential therapeutic strategy for ameliorating cardiovascular restenosis. [Display omitted] • ILF3 promotes injury-induced VSMC phenotype switching by lowering DUSP16 expression • ILF3 suppresses DUSP16 expression by enhancing HMGB1 mRNA stability • ILF3 aids VSMC proliferation and migration via HMGB1/STAT3/DUSP16 axis regulation • Post-vascular injury genetic inhibition of ILF3 alleviated neointimal hyperplasia [ABSTRACT FROM AUTHOR]

Cardiovascular diseases are the number one cause of death globally. The most important determinant of cardiovascular health is a person's age. Aging results in structural changes and functional decline of the cardiovascular system. DNA damage is an important contributor to the aging process, and mice with a DNA repair defect caused by Ercc1 deficiency display hypertension, vascular stiffening, and loss of vasomotor control. To determine the underlying cause, we compared important hallmarks of vascular aging in aortas of both Ercc1Δ/− and age‐matched wildtype mice. Additionally, we investigated vascular aging in 104 week old wildtype mice. Ercc1Δ/− aortas displayed arterial thickening, a loss of cells, and a discontinuous endothelial layer. Aortas of 24 week old Ercc1Δ/− mice showed phenotypical switching of vascular smooth muscle cells (VSMCs), characterized by a decrease in contractile markers and a decrease in synthetic markers at the RNA level. As well as an increase in osteogenic markers, microcalcification, and an increase in markers for damage induced stress response. This suggests that Ercc1Δ/− VSMCs undergo a stress‐induced contractile‐to‐osteogenic phenotype switch. Ercc1Δ/− aortas showed increased MMP activity, elastin fragmentation, and proteoglycan deposition, characteristic of vascular aging and indicative of age‐related extracellular matrix remodeling. The 104 week old WT mice showed loss of cells, VSMC dedifferentiation, and senescence. In conclusion, Ercc1Δ/− aortas rapidly display many characteristics of vascular aging, and thus the Ercc1Δ/− mouse is an excellent model to evaluate drugs that prevent vascular aging in a short time span at the functional, histological, and cellular level. [ABSTRACT FROM AUTHOR]

Cells have an incredible ability to physically interact with neighboring cells and their environment. They can detect and respond to mechanical forces by converting mechanical stimuli into biochemical signals in a process known as mechanotransduction. This is a key process for the adaption of vascular smooth muscle and endothelial cells to altered flow and pressure conditions. Mechanical stimuli, referring to a physical force exerted on cells, are primarily sensed by transmembrane proteins and the actin cytoskeleton, which initiate a cascade of intracellular events, including the activation of signaling pathways, ion channels, and transcriptional regulators. Recent work has highlighted an important role of the transcriptional coactivators YAP/TAZ for mechanotransduction in vascular cells. Interestingly, the activity of YAP/TAZ decreases with age, providing a potential mechanism for the detrimental effects of aging in the vascular wall. In this review, we summarize the current knowledge on the functional role of YAP and TAZ in vascular endothelial and smooth muscle cells for mechanotransduction in homeostasis and disease. In particular, the review is focused on in vivo observations from conditional knockout (KO) models of YAP/TAZ and the potential implications these studies may have for our understanding of vascular disease development. [ABSTRACT FROM AUTHOR]

Krüppel‐like factor 13 (KLF13), a zinc finger transcription factor, is considered as a potential regulator of cardiomyocyte differentiation and proliferation during heart morphogenesis. However, its precise role in the dedifferentiation of vascular smooth muscle cells (VSMCs) during atherosclerosis and neointimal formation after injury remains poorly understood. In this study, we investigated the relationship between KLF13 and SM22α expression in normal and atherosclerotic plaques by bioanalysis, and observed a significant increase in KLF13 levels in the atherosclerotic plaques of both human patients and ApoE−/− mice. Knockdown of KLF13 was found to ameliorate intimal hyperplasia following carotid artery injury. Furthermore, we discovered that KLF13 directly binds to the SM22α promoter, leading to the phenotypic dedifferentiation of VSMCs. Remarkably, we observed a significant inhibition of platelet‐derived growth factor BB‐induced VSMCs dedifferentiation, proliferation, and migration when knocked down KLF13 in VSMCs. This inhibitory effect of KLF13 knockdown on VCMC function was, at least in part, mediated by the inactivation of p‐AKT signaling in VSMCs. Overall, our findings shed light on a potential therapeutic target for treating atherosclerotic lesions and restenosis after vascular injury. [ABSTRACT FROM AUTHOR]

C‐peptide, a byproduct of insulin synthesis believed to be biologically inert, is emerging as a multifunctional molecule. C‐peptide serves an anti‐inflammatory and anti‐atherogenic role in type 1 diabetes mellitus (T1DM) and early T2DM. C‐peptide protects endothelial cells by activating AMP‐activated protein kinase α, thus suppressing the activity of NAD(P)H oxidase activity and reducing reactive oxygen species (ROS) generation. It also prevents apoptosis by regulating hyperglycemia‐induced p53 upregulation and mitochondrial adaptor p66shc overactivation, as well as reducing caspase‐3 activity and promoting expression of B‐cell lymphoma‐2. Additionally, C‐peptide suppresses platelet‐derived growth factor (PDGF)‐beta receptor and p44/p42 mitogen‐activated protein (MAP) kinase phosphorylation to inhibit vascular smooth muscle cells (VSMC) proliferation. It also diminishes leukocyte adhesion by virtue of its capacity to abolish nuclear factor kappa B (NF‐kB) signaling, a major pro‐inflammatory cascade. Consequently, it is envisaged that supplementation of C‐peptide in T1DM might ameliorate or even prevent end‐organ damage. In marked contrast, C‐peptide increases monocyte recruitment and migration through phosphoinositide 3‐kinase (PI‐3 kinase)‐mediated pathways, induces lipid accumulation via peroxisome proliferator‐activated receptor γ upregulation, and stimulates VSMC proliferation and CD4+ lymphocyte migration through Src‐kinase and PI‐3K dependent pathways. Thus, it promotes atherosclerosis and microvascular damage in late T2DM. Indeed, C‐peptide is now contemplated as a potential biomarker for insulin resistance in T2DM and linked to increased coronary artery disease risk. This shift in the understanding of the pathophysiology of diabetes from being a single hormone deficiency to a dual hormone disorder warrants a careful consideration of the role of C‐peptide as a unique molecule with promising diagnostic, prognostic, and therapeutic applications. [ABSTRACT FROM AUTHOR]

We studied the effect of the purinergic signaling system and the contribution of Cl– transporters to isosmotic contraction of vascular smooth muscle cells (SMC), which results from the normalization of osmotic pressure after prolonged incubation in a hyposmotic medium. The study was carried out by myography of endothelium-denuded aortic ring segments of male Wistar rats. Isosmotic contraction was induced by placing vascular segments in normosmotic Krebs solution (120 mM NaCl) after a 40-minute incubation in a hyposmotic Krebs solution (40 mM NaCl). Purinergic receptors were activated by adenosine 5'-triphosphate (ATP, 500 µM), a nonselective P2X and P2Y receptor agonist, and uridine 5'-triphosphate (UTP, 500 µM), a selective P2Y receptor agonist. ATP and UTP abolished the transience of the aortic SMC isosmotic contraction without affecting its amplitude. Pretreatment of vascular segments with ATP and UTP during incubation in a hyposmotic solution completely suppressed the development of isosmotic contraction in the presence of ATP or UTP, but did not affect it without purinergic receptor activators. The Na+–K+–2Cl–-cotransporter (NKCC) inhibitor bumetanide (100 µM) abolished isosmotic contraction in the presence of ATP (not UTP) but restored its transience. The nonselective Cl– channel and Cl–/HCO3– exchanger blocker DIDS (100 µM) suppressed the development of isosmotic contraction in the presence of both ATP and UTP. The potassium channel blocker tetraethylammonium (10 mM) potentiated the contractile activity of UTP toward isosmotic volume contraction. Presumably, purinergic receptors abolish the transience of isosmotic contraction by activating Cl– currents through activation of P2Y receptors. The mechanism of interaction between the purinergic signaling system and Cl– transport during cell volume changes requires further investigation. [ABSTRACT FROM AUTHOR]

Purpose: Cold-induced vasodilation (CIVD) is an oscillatory rise in blood flow to glabrous skin that occurs in cold-exposed extremities. Dietary flavanols increase bioavailable nitric oxide, a proposed mediator of CIVD through active vasodilation and/or withdrawal of sympathetic vascular smooth muscle tone. However, no studies have examined the effects of flavanol intake on extremity skin perfusion during cold exposure. We tested the hypothesis that acute and 8-day flavanol supplementation would augment CIVD during single-digit cold water immersion (CWI). Methods: Eleven healthy adults (24 ± 6 years; 10 M/1F) ingested cocoa flavanols (900 mg/day) or caffeine- and theobromine-matched placebo for 8 days in a double-blind, randomized, crossover design. On Days 1 and 8, CIVD was assessed 2 h post-treatment. Subjects immersed their 3rd finger in warm water (42 °C) for 15 min before CWI (4 °C) for 30 min, during which nail bed and finger pad skin temperature were measured. Results: Flavanol ingestion had no effect on CIVD frequency (Day 1, Flavanol: 3 ± 2 vs. Placebo: 3 ± 2; Day 8, Flavanol: 3 ± 2 vs. Placebo: 3 ± 1) or amplitude (Day 1, Flavanol: 4.3 ± 1.7 vs. Placebo: 4.9 ± 2.6 °C; Day 8, Flavanol: 3.9 ± 1.9 vs. Placebo: 3.9 ± 2.0 °C) in the finger pad following acute or 8-day supplementation (P > 0.05). Furthermore, average, nadir, and apex finger pad temperatures during CWI were not different between treatments on Days 1 or 8 of supplementation (P > 0.05). Similarly, no differences in CIVD parameters were observed in the nail bed following supplementation (P > 0.05). Conclusion: These data suggest that cocoa flavanol ingestion does not alter finger CIVD. Clinical Trial Registration Clinicaltrials.gov Identifier: NCT04359082. April 24, 2020. [ABSTRACT FROM AUTHOR]

Aims Long non-coding RNA (LncRNA) small nucleolar RNA host gene 18 (SNHG18) has been widely implicated in cancers. However, little is known about its functional involvement in vascular diseases. Herein, we attempted to explore a role for SNHG18 in modulating vascular smooth muscle cell (VSMC) contractile phenotype and injury-induced neointima formation. Methods and results Analysis of single-cell RNA sequencing and transcriptomic datasets showed decreased levels of SNHG18 in injured and atherosclerotic murine and human arteries, which is positively associated with VSMC contractile genes. SNHG18 was upregulated in VSMCs by TGFβ1 through transcription factors Sp1 and SMAD3. SNHG18 gene gain/loss-of-function studies revealed that VSMC contractile phenotype was positively regulated by SNHG18. Mechanistic studies showed that SNHG18 promotes a contractile VSMC phenotype by up-regulating miR-22-3p. SNHG18 up-regulates miR-22 biogenesis and miR-22-3p production by competitive binding with the A-to-I RNA editing enzyme, adenosine deaminase acting on RNA-2 (ADAR2). Surprisingly, we observed that ADAR2 inhibited miR-22 biogenesis not through increasing A-to-I editing within primary miR-22, but by interfering with the binding of microprocessor complex subunit DGCR8 to primary miR-22. Importantly, perivascular SNHG18 overexpression in the injured vessels dramatically up-regulated the expression levels of miR-22-3p and VSMC contractile genes, and prevented injury-induced neointimal hyperplasia. Such modulatory effects were reverted by miR-22-3p inhibition in the injured arteries. Finally, we observed a similar regulator role for SNHG18 in human VSMCs and a decreased expression level of both SNHG18 and miR-22-3p in diseased human arteries; and we found that the expression level of SNHG18 was positively associated with that of miR-22-3p in both healthy and diseased human arteries. Conclusion We demonstrate that SNHG18 is a novel regulator in governing VSMC contractile phenotype and preventing injury-induced neointimal hyperplasia. Our findings have important implications for therapeutic targeting snhg18/miR-22-3p signalling in vascular diseases. [ABSTRACT FROM AUTHOR]

Conduit arterial disease in chronic kidney disease (CKD) is an important cause of cardiac complications. Cardiac function in CKD has not been studied in the absence of arterial disease. In an Alport syndrome model bred not to have conduit arterial disease, mice at 225 days of life (dol) had CKD equivalent to humans with CKD stage 4-5. Parathyroid hormone (PTH) and FGF23 levels were one log order elevated, circulating sclerostin was elevated, and renal activin A was strongly induced. Aortic Ca levels were not increased, and vascular smooth muscle cell (VSMC) transdifferentiation was absent. The CKD mice were not hypertensive, and cardiac hypertrophy was absent. Freshly excised cardiac tissue respirometry (Oroboros) showed that ADP-stimulated O2 flux was diminished from 52 to 22 pmol/mg (P = 0.022). RNA-Seq of cardiac tissue from CKD mice revealed significantly decreased levels of cardiac mitochondrial oxidative phosphorylation genes. To examine the effect of activin A signaling, some Alport mice were treated with a monoclonal Ab to activin A or an isotype-matched IgG beginning at 75 days of life until euthanasia. Treatment with the activin A antibody (Ab) did not affect cardiac oxidative phosphorylation. However, the activin A antibody was active in the skeleton, disrupting the effect of CKD to stimulate osteoclast number, eroded surfaces, and the stimulation of osteoclast-driven remodeling. The data reported here show that cardiac mitochondrial respiration is impaired in CKD in the absence of conduit arterial disease. This is the first report of the direct effect of CKD on cardiac respiration. [ABSTRACT FROM AUTHOR]

Neointimal hyperplasia is the main cause of vascular graft failure in the medium term. Vitamin D receptor activation modulates the biology of vascular smooth muscle cells and has been reported to protect from neointimal hyperplasia following endothelial injury. However, the molecular mechanisms are poorly understood. We have now explored the impact of the selective vitamin D receptor activator, paricalcitol, on neointimal hyperplasia, following guidewire-induced endothelial cell injury in rats, and we have assessed the impact of paricalcitol or vehicle on the expression of key cell stress factors. Guidewire-induced endothelial cell injury caused neointimal hyperplasia and luminal stenosis and upregulated the expression of the growth factor growth/differentiation factor-15 (GDF-15), the cytokine receptor CD74, NFκB-inducing kinase (NIK, an upstream regulator of the proinflammatory transcription factor NFκB) and the chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2). Immunohistochemistry confirmed the increased expression of the cellular proteins CD74 and NIK. Paricalcitol (administered in doses of 750 ng/kg of body weight, every other day) had a non-significant impact on neointimal hyperplasia and luminal stenosis. However, it significantly decreased GDF-15, CD74, NIK and MCP-1/CCL2 mRNA expression, which in paricalcitol-injured arteries remained within the levels found in control vehicle sham arteries. In conclusion, paricalcitol had a dramatic effect, suppressing the stress response to guidewire-induced endothelial cell injury, despite a limited impact on neointimal hyperplasia and luminal stenosis. This observation identifies novel molecular targets of paricalcitol in the vascular system, whose differential expression cannot be justified as a consequence of improved tissue injury. [ABSTRACT FROM AUTHOR]

Vascular smooth muscle cells (VSMCs) play a key role in aortic aneurysm formation. Bone morphogenetic proteins (BMPs) have been implicated as important regulators of VSMC phenotype, and dysregulation of the BMP pathway has been shown to be associated with vascular diseases. The aim of this study was to investigate for the first time the effects of BMP-4 on the VSMC phenotype and to understand its role in the development of thoracic aortic aneurysms (TAAs). Using the angiotensin II (AngII) osmotic pump model in mice, aortas from mice with VSMC-specific BMP-4 deficiency showed changes similar to AngII-infused aortas, characterised by a loss of contractile markers, increased fibrosis, and activation of matrix metalloproteinase 9. When BMP-4 deficiency was combined with AngII infusion, there was a significantly higher rate of apoptosis and aortic dilatation. In vitro, VSMCs with mRNA silencing of BMP-4 displayed a dedifferentiated phenotype with activated canonical BMP signalling. In contrast, BMP-2-deficient VSMCs exhibited the opposite phenotype. The compensatory regulation between BMP-2 and BMP-4, with BMP-4 promoting the contractile phenotype, appeared to be independent of the canonical signalling pathway. Taken together, these results demonstrate the impact of VSMC-specific BMP-4 deficiency on TAA development. [ABSTRACT FROM AUTHOR]

Atherosclerotic cardiovascular disease is a chronic condition that often copresents with type 2 diabetes and obesity. Glucagonlike peptide-1 receptor agonists (GLP-1RAs) are incretin mimetics endorsed by major professional societies for improving glycemic status and reducing atherosclerotic risk in people living with type 2 diabetes. Although the cardioprotective efficacy of GLP-1RAs and their relationship with traditional risk factors are well established, there is a paucity of publications that have summarized the potentially direct mechanisms through which GLP-1RAs mitigate atherosclerosis. This review aims to narrow this gap by providing comprehensive and in-depth mechanistic insight into the antiatherosclerotic properties of GLP-1RAs demonstrated across large outcome trials. Herein, we describe the landmark cardiovascular outcome trials that triggered widespread excitement around GLP-1RAs as a modern class of cardioprotective agents, followed by a summary of the origins of GLP-1RAs and their mechanisms of action. The effects of GLP-1RAs at each major pathophysiological milestone of atherosclerosis, as observed across clinical trials, animal models, and cell culture studies, are described in detail. Specifically, this review provides recent preclinical and clinical evidence that suggest GLP-1RAs preserve vessel health in part by preventing endothelial dysfunction, achieved primarily through the promotion of angiogenesis and inhibition of oxidative stress. These protective effects are in addition to the broad range of atherosclerotic processes GLP-1RAs target downstream of endothelial dysfunction, which include systemic inflammation, monocyte recruitment, proinflammatory macrophage and foam cell formation, vascular smooth muscle cell proliferation, and plaque development. [ABSTRACT FROM AUTHOR]

Impaired cholesterol efflux and/or uptake can influence arterial lipid accumulation leading to atherosclerosis. Here, we report that tripartite motif-containing protein 13 (TRIM13), a RING-type E3 ubiquitin ligase, plays a role in arterial lipid accumulation leading to atherosclerosis. Using molecular approaches and KO mouse model, we found that TRIM13 expression was induced both in the aorta and peritoneal macrophages (pMφ) of ApoE−/− mice in response to Western diet (WD) in vivo. Furthermore, proatherogenic cytokine interleukin-1β also induced TRIM13 expression both in pMφ and vascular smooth muscle cells. Furthermore, we found that TRIM13 via ubiquitination and degradation of liver X receptor (LXR)α/β downregulates the expression of their target genes ABCA1/G1 and thereby inhibits cholesterol efflux. In addition, TRIM13 by ubiquitinating and degrading suppressor of cytokine signaling 1/3 (SOCS1/3) mediates signal transducer and activator of transcription 1 (STAT1) activation, CD36 expression, and foam cell formation. In line with these observations, genetic deletion of TRIM13 by rescuing cholesterol efflux and inhibiting foam cell formation protects against diet-induced atherosclerosis. We also found that while TRIM13 and CD36 levels were increased, LXRα/β, ABCA1/G1, and SOCS3 levels were decreased both in Mφ and smooth muscle cells of stenotic human coronary arteries as compared to nonstenotic arteries. More intriguingly, the expression levels of TRIM13 and its downstream signaling molecules were correlated with the severity of stenotic lesions. Together, these observations reveal for the first time that TRIM13 plays a crucial role in diet-induced atherosclerosis, and that it could be a potential drug target against this vascular lesion. [ABSTRACT FROM AUTHOR]

Thoracic aortic dissection (TAD) is a highly dangerous cardiovascular disorder caused by weakening of the aortic wall, resulting in a sudden tear of the internal face. Progressive loss of the contractile apparatus in vascular smooth muscle cells (VSMCs) is a major event in TAD. Exploring the endogenous regulators essential for the contractile phenotype of VSMCs may aid the development of strategies to prevent TAD. Krüppel-like factor 15 (KLF15) overexpression was reported to inhibit TAD formation; however, the mechanisms by which KLF15 prevents TAD formation and whether KLF15 regulates the contractile phenotype of VSMCs in TAD are not well understood. Therefore, we investigated these unknown aspects of KLF15 function. We found that KLF15 expression was reduced in human TAD samples and β-aminopropionitrile monofumarate-induced TAD mouse model. Klf15KO mice are susceptible to both β-aminopropionitrile monofumarate- and angiotensin II-induced TAD. KLF15 deficiency results in reduced VSMC contractility and exacerbated vascular inflammation and extracellular matrix degradation. Mechanistically, KLF15 interacts with myocardin-related transcription factor B (MRTFB), a potent serum response factor coactivator that drives contractile gene expression. KLF15 silencing represses the MRTFB-induced activation of contractile genes in VSMCs. Thus, KLF15 cooperates with MRTFB to promote the expression of contractile genes in VSMCs, and its dysfunction may exacerbate TAD. These findings indicate that KLF15 may be a novel therapeutic target for the treatment of TAD. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to determine whether bone morphogenetic protein-4 (BMP-4), which increases in response to intimal hyperplasia, promotes phenotype transition in vascular smooth muscle cells (VSMCs). Methods: Balloon injury was used to induce intimal hyperplasia in rats. Hematoxylin-eosin staining was used to detect the alteration of vascular structure. Serum levels of BMP-4 and lactate were detected by ELISA. Human aortic smooth muscle cells (HA-SMCs) were cultured. Protein and mRNA expression levels were detected through Western blot and real-time PCR. Cell migration was measured by transwell assay. Results: Our data showed that serum concentration of BMP-4 was upregulated after balloon injury. Treatment with BMP-4 inhibitor DMH1 (4-(6-(4-isopropoxyphenyl)pyrazolo(1,5-a)pyrimidin-3-yl)quinoline) suppressed the abnormal expression of BMP-4 and inhibited the intimal hyperplasia induced by balloon injury. Compared to BMP-4-negative medium, BMP-4-positive medium was associated with higher synthetic VSMC marker expression levels and lower in contractile gene markers in cultured HA-SMCs. Transfection of monocarboxylic acid transporters-4 (MCT-4) siRNA inhibited the excretion of lactate induced by BMP-4. Conclusion: Our analyses provided evidence that BMP-4 and its regulator Smad-4 are key regulators in MCT-4-mediated lactate excretion. This indicates that BMP-4 stimulates the phenotypic transition of VSMCs via SMAD-4/MCT-4 signaling pathway. [ABSTRACT FROM AUTHOR]

The maintenance of normal vascular function and homeostasis is largely dependent on the signaling mechanisms that occur within and between cells of the vasculature. TGF-β-activated kinase 1 (TAK1), a multifaceted signaling molecule, has been shown to play critical roles in various tissue types. Although the precise function of TAK1 in the vasculature remains largely unknown, emerging evidence suggests its potential involvement in both physiological and pathological processes. A comprehensive search strategy was employed to identify relevant studies, PubMed, Web of Science, and other relevant databases were systematically searched using keywords related to TAK1, TABs and MAP3K7.In this review, we discussed the role of TAK1 in vascular signaling, with a focus on its function, activation, and related signaling pathways. Specifically, we highlight the TA1-TABs complex is a key factor, regulating vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) involved in the processes of inflammation, vascular proliferation and angiogenesis. This mini review aims to elucidate the evidence supporting TAK1 signaling in the vasculature, in order to better comprehend its beneficial and potential harmful effects upon TAK1 activation in vascular tissue. [ABSTRACT FROM AUTHOR]

Liver kinase B1 (Lkb1), encoded by serine/threonine kinase (Stk11), is a serine/threonine kinase and tumor suppressor that is strongly implicated in Peutz–Jeghers syndrome (PJS). Numerous studies have shown that mesenchymal‐specific Lkb1 is sufficient for the development of PJS‐like polyps in mice. However, the cellular origin and components of these Lkb1‐associated polyps and underlying mechanisms remain elusive. In this study, we generated tamoxifen‐inducible Lkb1flox/flox;Myh11‐Cre/ERT2 and Lkb1flox/flox;PDGFRα‐Cre/ERT2 mice, performed single‐cell RNA sequencing (scRNA‐seq) and imaging‐based lineage tracing, and aimed to investigate the cellular complexity of gastrointestinal polyps associated with PJS. We found that Lkb1flox/+;Myh11‐Cre/ERT2 mice developed gastrointestinal polyps starting at 9 months after tamoxifen treatment. scRNA‐seq revealed aberrant stem cell‐like characteristics of epithelial cells from polyp tissues of Lkb1flox/+;Myh11‐Cre/ERT2 mice. The Lkb1‐associated polyps were further characterized by a branching smooth muscle core, abundant extracellular matrix deposition, and high immune cell infiltration. In addition, the Spp1–Cd44 or Spp1–Itga8/Itgb1 axes were identified as important interactions among epithelial, mesenchymal, and immune compartments in Lkb1‐associated polyps. These characteristics of gastrointestinal polyps were also demonstrated in another mouse model, tamoxifen‐inducible Lkb1flox/flox;PDGFRα‐Cre/ERT2 mice, which developed obvious gastrointestinal polyps as early as 2–3 months after tamoxifen treatment. Our findings further confirm the critical role of mesenchymal Lkb1/Stk11 in gastrointestinal polyposis and provide novel insight into the cellular complexity of Lkb1‐associated polyp biology. © 2024 The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

Background: Mural cells are an essential perivascular cell population that associate with blood vessels and contribute to vascular stabilization and tone. In the embryonic zebrafish vasculature, pdgfrb and tagln are commonly used as markers for identifying pericytes and vascular smooth muscle cells. However, the overlapping and distinct expression patterns of these markers in tandem have not been fully described. Results: Here, we used the Tg(pdgfrb:Gal4FF; UAS:RFP) and Tg(tagln:NLS‐EGFP) transgenic lines to identify single‐ and double‐positive perivascular cell populations on the cranial, axial, and intersegmental vessels between 1 and 5 days postfertilization. From this comparative analysis, we discovered two novel regions of tagln‐positive cell populations that have the potential to function as mural cell precursors. Specifically, we found that the hypochord—a reportedly transient structure—contributes to tagln‐positive cells along the dorsal aorta. We also identified a unique mural cell progenitor population that resides along the midline between the neural tube and notochord and contributes to intersegmental vessel mural cell coverage. Conclusion: Together, our findings highlight the variability and versatility of tracking both pdgfrb and tagln expression in mural cells of the developing zebrafish embryo and reveal unexpected embryonic cell populations that express pdgfrb and tagln. Key Findings: Detailed analysis of pdgfrb/tagln vascular expression patterns in embryonic zebrafishIdentified novel regions of tagln‐positive populations such as the hypochord and a mural cell progenitor population adjacent to the midlineRevealed that the hypochord persists beyond the timepoints presented in previous reports [ABSTRACT FROM AUTHOR]

Objective of this systematic review and meta-analysis is to assess the alterations in VSMC function following acupuncture stimulation in CIS models. Methods: The databases PubMed, Web of Science, SCOPUS, and EMBASE were queried until November 2022 using a predetermined search strategy. The FORMAT BY SYRCLE guidelines were adhered to, and the risk of bias of the included studies was evaluated using the Risk of Bias tool developed by the Systematic Review Centre for Laboratory Animal Experimentation. The random-effects model was employed to estimate the standardized mean difference (SMD). Results: Eighteen articles are included in this review. Acupuncture showed significant positive effects on the region cerebral blood flow (SMD=8.15 [95% CI, 4.52 to 11.78]) and neurological deficiency (SMD=− 3.75 [95% CI, − 5.54 to − 1.97]). Descriptive analysis showed a probable mechanism of acupuncture stimulation in CIS rats related to VSMC function. Limitations and publication bias were presented in the studies. Conclusion: In this systematic review and meta-analysis, our findings indicate that acupuncture stimulation has the potential to improve regional cerebral blood flow and alleviate neurological deficits, possibly by regulating VSMC function. However, it is important to exercise caution when interpreting these results due to the limitations of animal experimental design and methodological quality. [ABSTRACT FROM AUTHOR]

Lysyl oxidase (LOX)-mediated extracellular matrix crosslinking modulates calcification in atherosclerosis and aortic valve disease; however, this enzyme also induces oxidative stress. We addressed the contribution of LOX-dependent oxidative stress to cardiovascular calcification. LOX is upregulated in human-calcified atherosclerotic lesions and atheromas from atherosclerosis-challenged LOX transgenic mice (TgLOXVSMC) and colocalized with a marker of oxidative stress (8-oxo-deoxyguanosine) in vascular smooth muscle cells (VSMCs). Similarly, in calcific aortic valves, high LOX expression was detected in valvular interstitial cells (VICs) positive for 8-oxo-deoxyguanosine, while LOX and LOXL2 expression correlated with osteogenic markers (SPP1 and RUNX2) and NOX2. In human VICs, mito-TEMPO and TEMPOL attenuated the increase in superoxide anion levels and the mineralization induced by osteogenic media (OM). Likewise, in OM-exposed VICs, β-aminopropionitrile (a LOX inhibitor) ameliorated both oxidative stress and calcification. Gain- and loss-of-function approaches in VICs demonstrated that while LOX silencing negatively modulates oxidative stress and calcification induced by OM, lentiviral LOX overexpression exacerbated oxidative stress and VIC calcification, effects that were prevented by mito-TEMPO, TEMPOL, and β-aminopropionitrile. Our data indicate that LOX-induced oxidative stress participates in the procalcifying effects of LOX activity in ectopic cardiovascular calcification, and highlight the multifaceted role played by LOX isoenzymes in cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Hutchinson--Gilford progeria syndrome (HGPS) is a rare disease caused by the expression of progerin, a mutant protein that accelerates aging and precipitates death. Given that atherosclerosis complications are the main cause of death in progeria, here, we investigated whether progerin- induced atherosclerosis is prevented in HGPSrev- Cdh5- CreERT2 and HGPSrev- SM22α- Cre mice with progerin suppression in endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), respectively. HGPSrev- Cdh5- CreERT2 mice were undistinguishable from HGPSrev mice with ubiquitous progerin expression, in contrast with the ameliorated progeroid phenotype of HGPSrev- SM22α- Cre mice. To study atherosclerosis, we generated atheroprone mouse models by overexpressing a PCSK9 gain- of- function mutant. While HGPSrev- Cdh5- CreERT2 and HGPSrev mice developed a similar level of excessive atherosclerosis, plaque development in HGPSrev- SM22α- Cre mice was reduced to wild- type levels. Our studies demonstrate that progerin suppression in VSMCs, but not in ECs, prevents exacerbated atherosclerosis in progeroid mice. [ABSTRACT FROM AUTHOR]

The effects of Covid-19 vaccines on vascular function are still controversial. We evaluated the effects of BNT162b2 vaccine (BioNTech and Pfizer) on endothelial function assessed by flow-mediated vasodilation (FMD) and vascular smooth muscle function assessed by nitroglycerine-induced vasodilation (NID). This study was a prospective observational study. A total of 23 medical staff at Hiroshima University Hospital were enrolled in this study. FMD and NID were measured before vaccination and two weeks and six months after the 2nd dose of vaccination. FMD was significantly smaller two weeks after the 2nd dose of vaccination than before vaccination (6.5±2.4% and 8.2±2.6%, p = 0.03). FMD was significantly larger at six months than at two weeks after the 2nd dose of vaccination (8.2±3.0% and 6.5±2.4%, p = 0.03). There was no significant difference between FMD before vaccination and that at six months after the 2nd dose of vaccination (8.2±2.6% to 8.2±3.0%, p = 0.96). NID values were similar before vaccination and at two weeks, and six months after vaccination (p = 0.89). The BNT162b2 Covid-19 vaccine temporally impaired endothelial function but not vascular smooth muscle function, and the impaired endothelial function returned to the baseline level within six months after vaccination. [ABSTRACT FROM AUTHOR]

Goats have achieved global prominence as essential livestock since their initial domestication, primarily owing to their remarkable adaptability to diverse environmental and production systems. Differential selection pressures influenced by climate have led to variations in their physical attributes, leaving genetic imprints within the genomes of goat breeds raised in diverse agroecological settings. In light of this, our study pursued a comprehensive analysis, merging environmental data with single nucleotide polymorphism (SNP) variations, to unearth indications of selection shaped by climate-mediated forces in goats. Through the examination of 43,300 SNPs from 51 indigenous goat breeds adapting to different climatic conditions using four analytical methods: latent factor mixed models (LFMM), F-statistics (Fst), Extended haplotype homozygosity across populations (XPEHH), and spatial analysis method (SAM), A total of 74 genes were revealed to display clear signs of selection, which are believed to be influenced by climatic conditions. Among these genes, 32 were consistently identified by at least two of the applied methods, and three genes (DENND1A, PLCB1, and ITPR2) were confirmed by all four approaches. Moreover, our investigation yielded 148 Gene Ontology (GO) terms based on these 74 genes, underlining pivotal biological pathways crucial for environmental adaptation. These pathways encompass functions like vascular smooth muscle contraction, cellular response to heat, GTPase regulator activity, rhythmic processes, and responses to temperature stimuli. Of significance, GO terms about endocrine regulation and energy metabolic responses, key for local adaptation were also uncovered, including biological processes, such as cell differentiation, regulation of peptide hormone secretion, and lipid metabolism. These findings contribute to our knowledge of the genetic structure of climate-triggered adaptation across the goat genome and have practical implications for marker-assisted breeding in goats. [ABSTRACT FROM AUTHOR]

Background: Diabetic vascular remodeling is the most important pathological basis of diabetic cardiovascular complications. The accumulation of advanced glycation end products (AGEs) caused by elevated blood glucose promotes the proliferation and migration of vascular smooth muscle cells (VSMCs), leading to arterial wall thickening and ultimately vascular remodeling. Therefore, the excessive proliferation and migration of VSMCs is considered as an important therapeutic target for vascular remodeling in diabetes mellitus. However, due to the lack of breakthrough in experiments, there is currently no effective treatment for the excessive proliferation and migration of VSMCs in diabetic patients. Bcl-2-associated athanogene 3 (BAG3) protein is a multifunctional protein highly expressed in skeletal muscle and myocardium. Previous research has confirmed that BAG3 can not only regulate cell survival and apoptosis, but also affect cell proliferation and migration. Since the excessive proliferation and migration of VSMCs is an important pathogenesis of vascular remodeling in diabetes, the role of BAG3 in the excessive proliferation and migration of VSMCs and its molecular mechanism deserve further investigation. Methods: In this study, BAG3 gene was manipulated in smooth muscle to acquire SM22αCre; BAG3FL/FL mice and streptozotocin (STZ) was used to simulate diabetes. Expression of proteins and aortic thickness of mice were detected by immunofluorescence, ultrasound and hematoxylin-eosin (HE) staining. Using human aorta smooth muscle cell line (HASMC), cell viability was measured by CCK-8 and proliferation was measured by colony formation experiment. Migration was detected by transwell, scratch experiments and Phalloidin staining. Western Blot was used to detect protein expression and Co-Immunoprecipitation (Co-IP) was used to detect protein interaction. Results: In diabetic vascular remodeling, AGEs could promote the interaction between BAG3 and signal transducer and activator of transcription 3 (STAT3), leading to the enhanced interaction between STAT3 and Janus kinase 2 (JAK2) and reduced interaction between STAT3 and extracellular signal-regulated kinase 1/2 (ERK1/2), resulting in accumulated p-STAT3(705) and reduced p-STAT3(727). Subsequently, the expression of matrix metallopeptidase 2 (MMP2) is upregulated, thus promoting the migration of VSMCs. Conclusions: BAG3 upregulates the expression of MMP2 by increasing p-STAT3(705) and decreasing p-STAT3(727) levels, thereby promoting vascular remodeling in diabetes. This provides a new orientation for the prevention and treatment of diabetic vascular remodeling. [ABSTRACT FROM AUTHOR]

In this study, we sought to investigate the mechanisms of action of miR-195-5p in the osteogenic differentiation of vascular smooth muscle cells (VSMCs), and thereby provide novel insights and a reference for the targeted therapy of arterial media calcification. VSMC differentiation was induced using sodium β-glycerophosphate, and we investigated the effects of transfecting cells with miR-195-5p mimics, vectors overexpressing Smad7, and the Wnt/β-catenin pathway inhibitor (KYA1797K) on VSMC differentiation by determining cell viability and apoptosis, and the mRNA and protein expression of factors associated with osteogenic differentiation and the Wnt/β-catenin pathway. The results revealed that miR-195-5p mimics enhanced the osteogenic differentiation of VSMCs induced by β-glycerophosphate, whereas the overexpression of Smad7 reversed this phenomenon. In addition, KYA1797K was found to promote the effects of Smad7 overexpression. In conclusion, by targeting, Smad7, miR-195-5p promotes the Wnt/β-catenin pathway. and thus the osteogenic differentiation of VSMCs. These findings will provide a reference for elucidating the mechanisms whereby miR-195-5p regulates osteogenic differentiation. [ABSTRACT FROM AUTHOR]

Background: The contractile phenotype of vascular smooth muscle cells (VSMCs) results in good diastolic and contractile capacities, and its altered function is the main pathophysiological basis for diseases such as hypertension. VSMCs exist as a synthetic phenotype in vitro, making it challenging to maintain a contractile phenotype for research. It is widely recognized that the common medium in vitro is significantly less crowded than in the in vivo environment. Additionally, VSMCs have a heightened sense for detecting changes in medium crowding. However, it is unclear whether macromolecular crowding (MMC) helps maintain the VSMCs contractile phenotype. Purpose: This study aimed to explore the phenotypic, behavioral and gene expression changes of VSMCs after increasing the crowding degree by adding carrageenan (CR). Methods: The degree of medium crowding was examined by a dynamic light scattering assay; VSMCs survival and activity were examined by calcein/PI cell activity and toxicity and CCK-8 assays; VSMCs phenotypes and migration were examined by WB and wound healing assays; and gene expression was examined by transcriptomic analysis and RT-qPCR. Results: Notably, 225 μg/mL CR significantly increased the crowding degree of the medium and did not affect cell survival. Simultaneously, CR significantly promoted the contraction phenotypic marker expression in VSMCs, shortened cell length, decreased cell proliferation, and inhibited cell migration. CR significantly altered gene expression in VSMCs. Specifically, 856 genes were upregulated and 1207 genes were downregulated. These alterations primarily affect the cellular ion channel transport, microtubule movement, respiratory metabolism, amino acid transport, and extracellular matrix synthesis. The upregulated genes were primarily involved in the cytoskeleton and contraction processes of VSMCs, whereas the downregulated genes were mainly involved in extracellular matrix synthesis. Conclusions: The in vitro study showed that VSMCs can maintain the contractile phenotype by sensing changes in the crowding of the culture environment, which can be maintained by adding CR. [ABSTRACT FROM AUTHOR]

The high incidence of restenosis after angioplasty has been the leading reason for the recurrence of coronary heart disease, substantially increasing the mortality risk for patients. However, current anti‐stenosis drug‐eluting stents face challenges due to their limited functions and long‐term safety concerns, significantly compromising their therapeutic effect. Herein, a stent‐free anti‐stenosis drug coating (denoted as Cur‐NO‐Gel) based on a peptide hydrogel is proposed. This hydrogel is formed by assembling a nitric oxide (NO) donor‐peptide conjugate as a hydrogelator and encapsulating curcumin (Cur) during the assembly process. Cur‐NO‐Gel has the capability to release NO upon β‐galactosidase stimulation and gradually release Cur through hydrogel hydrolysis. The in vitro experiments confirmed that Cur‐NO‐Gel protects vascular endothelial cells against oxidative stress injury, inhibits cellular activation of vascular smooth muscle cells, and suppresses adventitial fibroblasts. Moreover, periadventitial administration of Cur‐NO‐Gel in the angioplasty model demonstrate its ability to inhibit vascular stenosis by promoting reendothelialization, suppressing neointima hyperplasia, and preventing constrictive remodeling. Therefore, the study provides proof of concept for designing a new generation of clinical drugs in angioplasty. [ABSTRACT FROM AUTHOR]

Abdominal aortic aneurysm (AAA) is a life‐threatening vascular disease but effective drugs for treatment of AAA are still lacking. Recently, erythropoietin (EPO) is reported to induce AAA formation in apolipoprotein‐E knock out (ApoE−/−) mice but an effective antagonist is unknown. In this study, formoterol, a β2 adrenergic receptor (β2AR) agonist, is found to be a promising agent for inhibiting AAA. To test this hypothesis, ApoE−/− mice are treated with vehicle, EPO, and EPO plus low‐, medium‐, and high‐dose formoterol, respectively. The incidence of AAA is 0, 55%, 35%,10%, and 55% in these 5 groups, respectively. Mechanistically, senescence of vascular smooth muscle cell (VSMC) is increased by EPO while decreased by medium‐dose formoterol both in vivo and in vitro, manifested by the altered expression of senescence biomarkers including phosphorylation of H2AXserine139, senescence‐associated β‐galactosidase activity, and P21 protein level. In addition, expression of sirtuin 1 (SIRT1) in aorta is decreased in EPO‐induced AAA but remarkably elevated by medium‐dose formoterol. Knockdown of β2AR and blockage of cyclic adenosine monophosphate (cAMP) attenuate the inhibitory role of formoterol in EPO‐induced VSMC senescence. In summary, medium‐dose formoterol attenuates EPO‐induced AAA via β2AR/cAMP/SIRT1 pathways, which provides a promising medication for the treatment of AAA. [ABSTRACT FROM AUTHOR]