Sulforaphane Attenuates Angiotensin II-Induced Vascular Smooth Muscle Cell Migration via Suppression of NOX4/ROS/Nrf2 Signaling

F-53B stimulated vascular smooth muscle cell phenotypic switch and vascular remodeling via ferroptosis-related pathway

The compound 6:2 chlorinated polyfluorinated ether sulfonate (F53B), an alternative to perfluorooctane sulfonate (PFOS), has been widely utilized in China. Although the connection between the exposure and toxicity of F53B is established, the role and mechanisms of the compound in promoting vascular remodeling are yet to be elucidated. Thus, the present study investigated the impact of F53B on the function of vascular smooth muscle cells (VSMCs) and vascular remodeling. The data exhibited that F53B stimulates vascular morphological alterations in vivo, and exposure to the compound caused excessive VSMCs ferroptosis and phenotype switching, as determined using phenotype and molecular assays. Moreover, Fer-1 reversed F-53B-induced VSMC dysfunction and vascular remodeling. Furthermore, F53B activated the ferroptosis-related pathway, encompassing ATR expression and LOC101929922/miR-542-3p/ACSL4 pathway. Thus, the current results elaborated on the multifaceted toxicities of F53B that induce vascular remodeling, thereby necessitating the assessment of vasotoxicity risks associated with the compound.

Role of osteokines in atherosclerosis

Despite their diverse physiologies and roles, the heart, skeletal muscles, and smooth muscles all derive from a common embryonic source as bones. Moreover, bone tissue, skeletal and smooth muscles, and the heart share conserved signaling pathways. The maintenance of skeletal health is precisely regulated by osteocytes, osteoblasts, and osteoclasts through coordinated secretion of bone-derived factors known as osteokines. Increasing evidence suggests the involvement of osteokines in regulating atherosclerotic vascular disease. Therefore, this review aims to examine the evidence for the role of osteokines in atherosclerosis development and progression comprehensively. Specifically discussed are extensively studied osteokines in atherosclerosis such as osteocalcin, osteopontin, osteoprotegerin, and fibroblast growth factor 23. Additionally, we highlighted the effects of exercise on modulating these key regulators derived from bone tissue metabolism. We believe that gaining an enhanced understanding of how osteocalcin contributes to the process of atherosclerosis will enable us to develop targeted and comprehensive therapeutic strategies against diseases associated with its progression.

Gut microbiota: a superior operator for dietary phytochemicals to improve atherosclerosis

Mounting evidence implicates the gut microbiota as a possible key susceptibility factor for atherosclerosis (AS). The employment of dietary phytochemicals that strive to target the gut microbiota has gained scientific support for treating AS. This study conducted a general overview of the links between the gut microbiota and AS, and summarized available evidence that dietary phytochemicals improve AS via manipulating gut microbiota. Then, the microbial metabolism of several dietary phytochemicals was summarized, along with a discussion on the metabolites formed and the biotransformation pathways involving key gut bacteria and enzymes. This study additionally focused on the anti-atherosclerotic potential of representative metabolites from dietary phytochemicals, and investigated their underlying molecular mechanisms. In summary, microbiota-dependent dietary phytochemical therapy is a promising strategy for AS management, and knowledge of "phytochemical-microbiota-biotransformation" may be a breakthrough in the search for novel anti-atherogenic agents.

The Role of NRF2 in Cerebrovascular Protection: Implications for Vascular Cognitive Impairment and Dementia (VCID)

Vascular cognitive impairment and dementia (VCID) represents a broad spectrum of cognitive decline secondary to cerebral vascular aging and injury. It is the second most common type of dementia, and the prevalence continues to increase. Nuclear factor erythroid 2-related factor 2 (NRF2) is enriched in the cerebral vasculature and has diverse roles in metabolic balance, mitochondrial stabilization, redox balance, and anti-inflammation. In this review, we first briefly introduce cerebrovascular aging in VCID and the NRF2 pathway. We then extensively discuss the effects of NRF2 activation in cerebrovascular components such as endothelial cells, vascular smooth muscle cells, pericytes, and perivascular macrophages. Finally, we summarize the clinical potential of NRF2 activators in VCID.

Eugenol Inhibits Ox-LDL-Induced Proliferation and Migration of Human Vascular Smooth Muscle Cells by Inhibiting the Ang II/MFG-E8/MCP-1 Signaling Cascade

Objective

In this study, we investigated the effect and mechanism of action of eugenol on oxidized low-density lipoprotein (ox-LDL)-induced abnormal proliferation and migration of human vascular smooth muscle cells (HVSMCs).

Methods

HVSMCs were treated with 100 ug/mL ox-LDL for 24 hours to establish a cell model. After 1-hour pretreatment, eugenol at concentrations of 5, 25, and 50 uM was added. Cell viability was assessed using an MTT assay, PCNA expression was detected using Western blot, cell cycle distribution was analyzed using flow cytometry, and cell migration ability was evaluated using wound healing and Transwell migration assays. To investigate the mechanisms, Ang II receptors were inhibited by 1000 nM valsartan, MFG-E8 was knocked down by shRNA, MCP-1 was inhibited by siRNA, and MFG-E8 was overexpressed using plasmids.

Results

The findings from this study elucidated the stimulatory impact of ox-LDL on the proliferation and functionality of HVSMCs. Different concentrations of eugenol effectively mitigated the enhanced activity of HVSMCs induced by ox-LDL, with 50 uM eugenol exhibiting the most pronounced inhibitory effect. Flow cytometry and Western blot results showed ox-LDL reduced G1 phase cells and increased PCNA expression, while 50 uM eugenol inhibited ox-LDL-induced HVSMC proliferation. In wound healing and Transwell migration experiments, the ox-LDL group showed larger cell scratch filling and migration than the control group, both of which were inhibited by 50 uM eugenol. Inhibiting the Ang II/MFG-E8/MCP-1 signaling cascade mimicked eugenol's effects, while MFG-E8 overexpression reversed eugenol's inhibitory effect.

Conclusion

Eugenol can inhibit the proliferation and migration of ox-LDL-induced HVSMCs by inhibiting Ang II/MFG-E8/MCP-1 signaling cascade, making it a potential therapeutic drug for atherosclerosis.

Hexahydrocurcumin mitigates angiotensin II-induced proliferation, migration, and inflammation in vascular smooth muscle cells

The proliferation and migration of vascular smooth muscle cells (VSMCs) play vital roles in the pathogenesis of atherosclerosis and hypertension. It has been proposed and verified that hexahydrocurcumin (HHC), a metabolite form of curcumin, has cardiovascular protective effects. This study examined the effect of HHC on angiotensin II (Ang II)-induced proliferation, migration, and inflammation in rat aortic VSMCs and explored the molecular mechanisms related to the processes. The results showed that HHC significantly suppressed Ang II-induced proliferation, migration, and inflammation in VSMCs. HHC inhibited Ang II-induction of the increase in cyclin D1 and decrease in p21 expression in VSMCs. Moreover, HHC attenuated the generation of reactive oxygen species (ROS), and the expression of nuclear factor kappa B (NF-κB), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and matrix metalloproteinases-9 (MMP9) in Ang II-induced VSMCs. The proliferation, migration, inflammation, and ROS production were also inhibited by GKT137831 (NADPH oxidase, NOX1/4 inhibitor) and the combination of HHC and GKT137831. In addition, HHC restored the Ang-II inhibited expression of peroxisome proliferator-activated receptor-γ (PPAR-γ) and peroxisome proliferator activated receptor-γ coactivator-1α (PGC-1α). These findings indicate that HHC may play a protective role in Ang II-promoted proliferation, migration, and inflammation by suppressing NADPH oxidase mediated ROS generation and elevating PPAR-γ and PGC-1α expression. See also Figure 1(Fig. 1).

Inflachromene inhibits intimal hyperplasia through the HMGB1/2- regulated TLR4-NF-κB pathway

The contractile-syntheticphenotypicconversion of vascular smooth muscle cells (VSMCs) plays a key role in atherosclerosis, vascular restenosis, and hypertension. Our previous study explored the correlation between high mobility group box protein (HMGB) 1 and HMGB2 and neointimal hyperplasia after vascular injury. In the present study, we explore whether inflachromene (ICM), a novel inhibitor of the expression of both HMGB1 and HMGB2, modulates phenotypic changes in VSMCs and the mechanisms involved. Mice treated with ICM after carotid artery wire injury showed a decrease in excessive neointimal hyperplasia compared with that in the vehicle groups. In cultured VSMCs, pretreatment with ICM suppressed the angiotensin II (Ang II)-induced phenotypic conversion, proliferation, and migration. We discovered that ICM reduced the Ang II-induced upregulation of the expression of HMGB1 and HMGB2 and inhibited their shuttling between the nucleus and the cytosol. Mechanistically, Ang II-treated VSMCs exhibited higher levels of Toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) phosphorylation, which were attenuated by ICM. In addition, the NF-κB inhibitor Bay-117082 abolished the recombinant HMGB1-mediated VSMC phenotypic conversion, proliferation, and migration. Furthermore, ICM ameliorated the Ang II-induced increases in NAD[P]H oxidase expression, thereby attenuating the Ang II-induced proliferation and migration. These results reveal that ICM pretreatment attenuates Ang II-induced VSMC dedifferentiation, proliferation, and migration may by regulating the TLR4-NF-kB pathway. Thus, ICM is a potential therapy and preventive treatment for vascular proliferative diseases.

Dietary Evodiamine Inhibits Atherosclerosis-Associated Changes in Vascular Smooth Muscle Cells

Evodia rutaecarpa (Juss.) Benth is a traditional Chinese medicine. The active ingredient, evodiamine, is a quinolone alkaloid and is found in Evodiae fructus. We investigated the effect of evodiamine on atherosclerosis using LDLR−/− mice fed on a high-fat diet and ox-LDL-induced MOVAS cell lines to construct mouse models and cell-line models. We report a significant reduction in atherosclerotic plaque formation in mice exposed to evodiamine. Our mechanistic studies have revealled that evodiamine can regulate the proliferation, migration, and inflammatory response of and oxidative stress in vascular smooth muscle cells by inhibiting the activation of the PI3K/Akt axis, thus inhibiting the occurrence and development of atherosclerosis. In conclusion, our findings reveal a role for evodiamine in the regulation of vascular smooth muscle cells in atherosclerosis, highlighting a potential future role for the compound as an anti-atherosclerotic agent.

Cyclophilin D-mediated angiotensin II-induced NADPH oxidase 4 activation in endothelial mitochondrial dysfunction that can be rescued by gallic acid

Vascular endothelial dysfunction plays a central role in the most dreadful human diseases, including stroke, tumor metastasis, and the coronavirus disease 2019 (COVID-19). Strong evidence suggests that angiotensin II (Ang II)-induced mitochondrial dysfunction is essential for endothelial dysfunction pathogenesis. However, the precise molecular mechanisms remain obscure. Here, polymerase-interacting protein 2 (Poldip 2) was found in the endothelial mitochondrial matrix and no effects on Poldip 2 and NADPH oxidase 4 (NOX 4) expression treated by Ang II. Interestingly, we first found that Ang II-induced NOX 4 binds with Poldip 2 was dependent on cyclophilin D (CypD). CypD knockdown (KD) significantly inhibited the binding of NOX 4 to Poldip 2, and mitochondrial ROS generation in human umbilical vein endothelial cells (HUVECs). Similar results were also found in cyclosporin A (CsA) treated HUVECs. Our previous study suggested a crosstalk between extracellular regulated protein kinase (ERK) phosphorylation and CypD expression, and gallic acid (GA) inhibited mitochondrial dysfunction in neurons depending on regulating the ERK-CypD axis. Here, we confirmed that GA inhibited Ang II-induced NOX 4 activation and mitochondrial dysfunction via ERK/CypD/NOX 4/Poldip 2 pathway, which provide novel mechanistic insight into CypD act as a key regulator of the NOX 4/Poldip 2 axis in Ang II-induced endothelial mitochondrial dysfunction and GA might be beneficial in the treatment of wide variety of diseases, such as COVID-19, which is worthy further research.

Essential role of Nrf2 in sulforaphane-induced protection against angiotensin II-induced aortic injury

AIMS

Cardiovascular disease (CVD) is the leading cause of death worldwide. Inflammation and oxidative stress are the primary factors underlying angiotensin II (Ang II)-induced aortic damage. Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important antioxidative stress factor. Sulforaphane (SFN), which is naturally found in cruciferous vegetables, is an Nrf2 agonist that is safe for oral administration. Here, we aimed to explore the potential of SFN in protecting against Ang II-induced aortic damage by upregulating Nrf2 expression via the extracellular signal-regulated kinase (ERK)/glycogen synthase kinase-3 beta (GSK-3β)/Fyn pathway.

MAIN METHODS AND KEY FINDINGS

Wild-type (WT) C57BL/6J and Nrf2-knockout (Nrf2-KO) mice were injected with Ang II to induce aortic inflammation, oxidative stress, and cardiac remodeling (increased fibrosis and wall thickness). SFN treatment prevented aortic damage via Nrf2 activation in the WT mice. However, the protective effect of SFN on Ang II-induced aortic damage and upregulation of genes downstream of Nrf2 were not observed in Nrf2-KO mice. SFN induced the upregulation of aortic Nrf2 and inhibited the accumulation of ERK, GSK-3β, and Fyn in the nuclei.

SIGNIFICANCE

These results revealed that Nrf2 plays a central role in protecting against Ang II-induced aortic injury. Furthermore, SFN prevented Ang II-induced aortic damage by activating Nrf2 through the ERK/GSK-3β/Fyn pathway.

Nrf2-Mediated Dichotomy in the Vascular System: Mechanistic and Therapeutic Perspective

Nuclear factor-erythroid 2-related factor 2 (Nrf2), a transcription factor, controls the expression of more than 1000 genes that can be clustered into different categories with distinct functions ranging from redox balance and metabolism to protein quality control in the cell. The biological consequence of Nrf2 activation can be either protective or detrimental in a context-dependent manner. In the cardiovascular system, most studies have focused on the protective properties of Nrf2, mainly as a key transcription factor of antioxidant defense. However, emerging evidence revealed an unexpected role of Nrf2 in mediating cardiovascular maladaptive remodeling and dysfunction in certain disease settings. Herein we review the role of Nrf2 in cardiovascular diseases with a focus on vascular disease. We discuss the negative effect of Nrf2 on the vasculature as well as the potential underlying mechanisms. We also discuss the clinical relevance of targeting Nrf2 pathways for the treatment of cardiovascular and other diseases.

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.

Beneficial Health Effects of Glucosinolates-Derived Isothiocyanates on Cardiovascular and Neurodegenerative Diseases

Neurodegenerative diseases (NDDs) and cardiovascular diseases (CVDs) are illnesses that affect the nervous system and heart, all of which are vital to the human body. To maintain health of the human body, vegetable diets serve as a preventive approach and particularly Brassica vegetables have been associated with lower risks of chronic diseases, especially NDDs and CVDs. Interestingly, glucosinolates (GLs) and isothiocyanates (ITCs) are phytochemicals that are mostly found in the Cruciferae family and they have been largely documented as antioxidants contributing to both cardio- and neuroprotective effects. The hydrolytic breakdown of GLs into ITCs such as sulforaphane (SFN), phenylethyl ITC (PEITC), moringin (MG), erucin (ER), and allyl ITC (AITC) has been recognized to exert significant effects with regards to cardio- and neuroprotection. From past in vivo and/or in vitro studies, those phytochemicals have displayed the ability to mitigate the adverse effects of reactive oxidation species (ROS), inflammation, and apoptosis, which are the primary causes of CVDs and NDDs. This review focuses on the protective effects of those GL-derived ITCs, featuring their beneficial effects and the mechanisms behind those effects in CVDs and NDDs.

NRF2 Activation and Downstream Effects: Focus on Parkinson's Disease and Brain Angiotensin

Reactive oxygen species (ROS) are signalling molecules used to regulate cellular metabolism and homeostasis. However, excessive ROS production causes oxidative stress, one of the main mechanisms associated with the origin and progression of neurodegenerative disorders such as Parkinson's disease. NRF2 (Nuclear Factor-Erythroid 2 Like 2) is a transcription factor that orchestrates the cellular response to oxidative stress. The regulation of NRF2 signalling has been shown to be a promising strategy to modulate the progression of the neurodegeneration associated to Parkinson's disease. The NRF2 pathway has been shown to be affected in patients with this disease, and activation of NRF2 has neuroprotective effects in preclinical models, demonstrating the therapeutic potential of this pathway. In this review, we highlight recent advances regarding the regulation of NRF2, including the effect of Angiotensin II as an endogenous signalling molecule able to regulate ROS production and oxidative stress in dopaminergic neurons. The genes regulated and the downstream effects of activation, with special focus on Kruppel Like Factor 9 (KLF9) transcription factor, provide clues about the mechanisms involved in the neurodegenerative process as well as future therapeutic approaches.

Aldosterone Negatively Regulates Nrf2 Activity: An Additional Mechanism Contributing to Oxidative Stress and Vascular Dysfunction by Aldosterone

High levels of aldosterone (Aldo) trigger oxidative stress and vascular dysfunction independent of effects on blood pressure. We sought to determine whether Aldo disrupts Nrf2 signaling, the main transcriptional factor involved in antioxidant responses that aggravate cell injury. Thoracic aorta from male C57Bl/6J mice and cultured human endothelial cells (EA.hy926) were stimulated with Aldo (100 nM) in the presence of tiron [reactive oxygen species (ROS) scavenger, eplerenone [mineralocorticoid receptor (MR) antagonist], and L-sulforaphane (SFN; Nrf2 activator). Thoracic aortas were also isolated from mice infused with Aldo (600 μg/kg per day) for 14 days. Aldo decreased endothelium-dependent vasorelaxation and increased ROS generation, effects prevented by tiron and MR blockade. Pharmacological activation of Nrf2 with SFN abrogated Aldo-induced vascular dysfunction and ROS generation. In EA.hy926 cells, Aldo increased ROS generation, which was prevented by eplerenone, tiron, and SFN. At short times, Aldo-induced ROS generation was linked to increased Nrf2 activation. However, after three hours, Aldo decreased the nuclear accumulation of Nrf2. Increased Keap1 protein expression, but not activation of p38 MAPK, was linked to Aldo-induced reduced Nrf2 activity. Arteries from Aldo-infused mice also exhibited decreased nuclear Nrf2 and increased Keap1 expression. Our findings suggest that Aldo reduces vascular Nrf2 transcriptional activity by Keap1-dependent mechanisms, contributing to mineralocorticoid-induced vascular dysfunction.

Redox Homeostasis in Muscular Dystrophies

In recent years, growing evidence has suggested a prominent role of oxidative stress in the pathophysiology of several early- and adult-onset muscle disorders, although effective antioxidant treatments are still lacking. Oxidative stress causes cell damage by affecting protein function, membrane structure, lipid metabolism, and DNA integrity, thus interfering with skeletal muscle homeostasis and functionality. Some features related to oxidative stress, such as chronic inflammation, defective regeneration, and mitochondrial damage are shared among most muscular dystrophies, and Nrf2 has been shown to be a central player in antagonizing redox imbalance in several of these disorders. However, the exact mechanisms leading to overproduction of reactive oxygen species and deregulation in the cellular antioxidants system seem to be, to a large extent, disease-specific, and the clarification of these mechanisms in vivo in humans is the cornerstone for the development of targeted antioxidant therapies, which will require testing in appropriately designed clinical trials.

[Angiotensin Ⅱ inhibits AMPK/SIRT1 pathway by inducing oxidative stress in RAW264.7 macrophages]

OBJECTIVE

To investigate the mechanism by which angiotensin Ⅱ-induced oxidative stress response inhibits AMPK/ SIRT1 signaling in RAW264.7 macrophages.

OBJECTIVE

RAW264.7 cells were treated with 0.5, 1, 3, 10, or 20 μmol/L angiotensin Ⅱ for 24 h, and the changes in the expressions of AMPK, p-AMPK, and SIRT1 proteins were detected using Western blotting. The intracellular ROS release level was measured and the levels of SOD and MDA were detected. The effects of angiotensin Ⅱ type 1 receptor (AT1R) gene silencing on the cell response to angiotensin Ⅱ treatment were examined by detecting the changes in AMPK, p-AMPK and SIRT1 protein levels. The effects of a ROS inhibitor on cellular AMPK and SIRT1 were also examined.

OBJECTIVE

Angiotensin Ⅱ stimulation at 20 μmol/L significantly inhibited the phosphorylation of AMPK protein and increased cellular ROS release (P < 0.05). Treatment with 0.5-10 μmol/L angiotensin Ⅱ did not cause significant changes in SOD activity or MDA expression, but angiotensin Ⅱ at the dose of 20 μmol/L significantly inhibited SOD activity in the cells (P < 0.05). In the macrophages with AT1R gene silencing, treatment with angiotensin Ⅱ did not obviously inhibit AMPK phosphorylation or down- regulate SIRT1 expression. In cells treated with the ROS inhibitor, angiotensin Ⅱ failed to lower the level of AMPK phosphorylation or the expression of SIRT1.

OBJECTIVE

Angiotensin Ⅱ induces oxidative stress to cause disturbance of AMPK/ SIRT1 signaling pathway in macrophages.

Nrf2-interacting nutrients and COVID-19: time for research to develop adaptation strategies

There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPARγ:Peroxisome proliferator-activated receptor, NFκB: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2α:Elongation initiation factor 2α). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT₁R axis (AT₁R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity.

Activation of M3AChR (Type 3 Muscarinic Acetylcholine Receptor) and Nrf2 (Nuclear Factor Erythroid 2-Related Factor 2) Signaling by Choline Alleviates Vascular Smooth Muscle Cell Phenotypic Switching and Vascular Remodeling

OBJECTIVE

Phenotypic switching of vascular smooth muscle cells (VSMCs) plays a critical role in atherosclerosis, vascular restenosis, and hypertension. Choline exerts cardioprotective effects; however, little is known about its effects on VSMC phenotypic switching and vascular remodeling. Here, we investigated whether choline modulates VSMC phenotypic changes and explored the underlying mechanisms. Approach and Results: In cultured VSMCs, choline promoted Nrf2 (nuclear factor erythroid 2-related factor 2) nuclear translocation, inducing the expression of HO-1 (heme oxygenase-1) and NQO-1 (NAD[P]H quinone oxidoreductase-1). Consequently, choline ameliorated Ang II (angiotensin II)-induced increases in NOX (NAD[P]H oxidase) expression and the mitochondrial reactive oxygen species level, thereby attenuating Ang II-induced VSMC phenotypic switching, proliferation, and migration, presumably via M3AChRs (type 3 muscarinic acetylcholine receptors). Downregulation of M3AChR or Nrf2 diminished choline-mediated upregulation of Nrf2, HO-1, and NQO-1 expression, as well as inhibition of VSMC phenotypic transformation, suggesting that M3AChR and Nrf2 activation are responsible for the protective effects of choline. Moreover, activation of the Nrf2 pathway by sulforaphane suppressed Ang II-induced VSMC phenotypic switching and proliferation, indicating that Nrf2 is a key regulator of VSMC phenotypic switching and vascular homeostasis. In a rat model of abdominal aortic constriction in vivo, choline attenuated VSMC phenotypic transformation and vascular remodeling in a manner related to activation of the Nrf2 pathway.

CONCLUSIONS

These results reveal that choline impedes VSMC phenotypic switching, proliferation, migration, and vascular remodeling by activating M3AChR and Nrf2-antioxidant signaling and suggest a novel role for Nrf2 in VSMC phenotypic modulation.

Sulforaphane improves vascular reactivity in mouse and human arteries after "preeclamptic-like" injury

INTRODUCTION

The widespread maternal endothelial dysfunction that underlies the manifestations of preeclampsia is thought to arise from excessive placental production of antiangiogenic factors and enhanced oxidative stress. Therefore, we assessed whether the natural antioxidant sulforaphane could improve vascular function.

METHODS

Cell viability of human umbilical vein endothelial cells (HUVECs) was assessed after 24 or 48 h in normoxia (20% O₂) or hypoxia (1% O₂) with or without sulforaphane. To model vascular dysfunction associated with preeclampsia, mouse mesenteric arteries were incubated in trophoblast conditioned media (TCM), and human omental arteries incubated in preeclamptic explant media (PEM) with or without sulforaphane. Both media are rich in antiangiogenic compounds associated with preeclampsia. TCM was generated from primary cytotrophoblast cells from term placentae of normotensive, while PEM was generated from explants from preeclamptic women. Reactivity was assessed by wire myography. sulforaphane's actions as a vasodilator were also investigated.

RESULTS

Under conditions of hypoxia, sulforaphane improved HUVEC viability. In mouse mesenteric arteries, sulforaphane reduced contraction evoked by potassium (p < 0.001), phenylephrine and endothelin 1 (all p < 0.001). Sulforaphane also inhibited Ca²⁺-induced contraction (p = 0.014). Sulforaphane prevented TCM-induced augmentation of phenylephrine and angiotensin II-mediated contraction of mouse mesenteric arteries. In human omental arteries, sulforaphane induced vasodilation (p < 0.001), and prevented PEM-induced endothelial dysfunction by restoring arterial sensitivity to the endothelium-dependent vasodilator bradykinin (p = 0.008).

DISCUSSION

Sulforaphane causes relaxation in arteries and protects against arterial dysfunction induced by placental-derived antiangiogenic factors, which are known to contribute to the preeclampsia.

The role of NOX4 in pulmonary diseases

Nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) is a subtype of the NOX family, which is mainly expressed in the pulmonary vasculature and pulmonary endothelial cells in the respiratory system. NOX4 has unique characteristics, and is a constitutively active enzyme that primarily produces hydrogen peroxide. The signaling pathways associated with NOX4 are complicated. Negative and positive feedback play significant roles in regulating NOX4 expression. The role of NOX4 is controversial because NOX4 plays a protective or damaging role in different respiratory diseases. This review summarizes the structure, enzymatic properties, regulation, and signaling pathways of NOX4. This review then introduces the roles of NOX4 in different diseases in the respiratory system, such as acute respiratory distress syndrome, chronic obstructive pulmonary disease, and pulmonary fibrosis.

Smooth muscle NADPH oxidase 4 promotes angiotensin II-induced aortic aneurysm and atherosclerosis by regulating osteopontin

BACKGROUND AND AIMS

Angiotensin II (Ang II) is commonly used to induce aortic aneurysm and atherosclerosis in animal models. Ang II upregulates NADPH oxidase isoform Nox4 in aortic smooth muscle cells (SMCs) in mice. However, whether smooth muscle Nox4 is directly involved in Ang II-induced aortic aneurysm and atherosclerosis is unclear.

METHODS & RESULTS

To address this, we used smooth muscle-specific Nox4 dominant-negative (SDN) transgenic mice, in which Nox4 activity is constitutively inhibited. In non-transgenic (NTg) mice, Ang II increased the expression of proteins known to contribute to both aortic aneurysm and atherosclerosis, namely osteopontin (OPN), collagen type I&III (Col I&III), matrix metalloproteinase 2 (MMP2), and vascular cell adhesion molecule 1 (VCAM1), which were all significantly downregulated in SDN mice. The number and size of Ang II-induced aorta collateral aneurysms and atherosclerotic lesions in the renal artery and aortic root of SDN mice were significantly decreased compared to NTg mice, and directly correlated with a decrease in OPN expression. Replenishing OPN in SDN SMCs, increased the expression of Col I&III, MMP2, and VCAM1, and promoted SMC proliferation, migration, and inflammation.

CONCLUSIONS

Our data demonstrate that smooth muscle Nox4 directly promotes the development of Ang II-induced aortic aneurysm and atherosclerosis, at least in part, through regulating OPN expression.

Chemokine-like factor 1 (CKLF1) aggravates neointimal hyperplasia through activating the NF-κB /VCAM-1 pathway

Neointimal hyperplasia (NIH) is a complicated inflammatory process contributing to vascular restenosis. The present study aimed to explore whether chemokine-like factor 1 (CKLF1) aggravates NIH via the nuclear factor-kappa B (NF-κB)/vascular cell adhesion molecule-1 (VCAM-1) pathway. We found the expression of CKLF1 and VCAM-1 significantly increased in human carotid plaques compared to the control. In vivo, CKLF1 overexpression induced a thicker neointimal formation and VCAM-1 expression was correspondingly upregulated. In vitro, CKLF1 activated NF-κB and induced VCAM-1 upregulation in human aortic smooth muscle cells (HASMCs). Functional experiments demonstrated that CKLF1 promoted monocyte adhesion and HASMC migration via VCAM-1. These results suggest CKLF1 accelerates NIH by promoting monocyte adhesion and HASMC migration via the NF-κB/VCAM-1 pathway. Our findings contribute to a better understanding of the mechanisms underlying the causality of CKLF1 on NIH and could prove beneficial in designing therapeutic modalities with a focus on CKLF1.

miR-96-5p Regulates Proliferation, Migration, and Apoptosis of Vascular Smooth Muscle Cell Induced by Angiotensin II via Targeting NFAT5

BACKGROUND

Aberrant proliferation, migration, and apoptosis of vascular smooth muscle cells (VSMCs) are major pathological phenomenon in hypertension. MicroRNAs (miRNAs/miRs) serve crucial roles in the progression of hypertension. We aimed to determine the role of miR-96-5p in the proliferation, migration, and apoptosis of VSMCs and its underlying mechanisms.

METHODS

Angiotensin II (Ang II) was employed to treat VSMCs, and the expression of miR-96-5p was detected by RT-qPCR. Then, miR-96-5p mimic was transfected into VSMCs. Cell Counting Kit-8 assay, flow cytometry, transwell assay, and wound healing assay were applied to measure proliferation, cell cycle, and migration of VSMCs. The expression of proteins associated with proliferation, migration, and apoptosis was assessed. A luciferase reporter assay was applied to confirm the target binding between miR-96-5p and nuclear factors of activated T-cells 5 (NFAT5). Subsequently, siRNA was used to silence NFAT5, and cell proliferation, migration, and apoptosis were assessed.

RESULTS

The results revealed that the expression of miR-96-5p was downregulated in Ang II-induced VSMCs. MiR-96-5p overexpression inhibited cell proliferation and migration but promoted cell apoptosis, enhanced the percentages of cells in the G1 and G2 phases, and reduced those in the S phase, accompanied by changes in the expression associated proteins. NFAT5 was confirmed as a direct target of miR-96-5p. NFAT5 silencing had the same results with miR-96-5p overexpression on VSMC proliferation, migration, and apoptosis, whereas miR-96-5p inhibitor reversed these effects.

CONCLUSIONS

Our findings concluded that miR-96-5p could regulate proliferation, migration, and apoptosis of VSMCs induced by Ang II via targeting NFAT5.

Angiotensin II inhibits apoptosis of mouse aortic smooth muscle cells through regulating the circNRG-1/miR-193b-5p/NRG-1 axis

Angiotensin II (Ang II) is known to promote proliferation of vascular smooth muscle cells (VSMCs) in vascular remodeling, but whether it has an anti-apoptotic effect needs to be explored. Neuregulin-1 (NRG-1) as a member of the epidermal growth factor family was reported to suppress the proliferation of VSMCs by activating ErbB receptors, and therefore we hypothesized that there might be a cross talk between the anti-apoptotic effect of Ang II and the anti-proliferative effect of NRG-1 in VSMCs. The aim of the present study was to observe the expression and role of NRG-1 underlying the inhibitory effect of Ang II on apoptosis of mouse aortic smooth muscle cells (MASMCs). It was found that NRG-1 expression was down-regulated via the circNRG-1/miR-193b-5p-mediated post-transcriptional mechanism in response to Ang II. In addition, NRG-1 overexpression reversed the inhibitory effect of Ang II on apoptosis in MASMCs. Our data may provide a molecular basis for further understanding the mechanism of Ang II in suppressing the apoptosis of MASMCs by decreasing NRG-1 expression at circular RNA and micro RNA levels. The circNRG-1/miR-193b-5p/NRG-1 axis may prove to be a potential target for Ang II to inhibit the apoptosis of VSMCs and lead to vascular remodeling.