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Long-term stress is a significant risk factor for cardiovascular diseases, including atherosclerosis and endothelial dysfunction. Moreover, prolonged stress has shown to negatively regulate central BDNF expression. The role of central BDNF in CNS disorders is well studied until recently the peripheral BDNF was also found to be involved in endothelial function regulation and atherosclerosis. The peripheral BDNF and its role in chronic stress-induced atherosclerosis and endothelial dysfunction remain unclear. Therefore, we aimed to elucidate the role of BDNF and its modulation by the HDAC inhibitor valproic acid (VA) in chronic unpredictable stress (CUS)-induced atherosclerosis and endothelial dysfunction. We demonstrated that a 10-week CUS mouse model substantially decreases central and peripheral BDNF expression, resulting in enhanced serum lipid indices, plaque deposition, fibrosis, and CD68 expression in thoracic aortas. Further, parameters associated with endothelial dysfunction such as increased levels of endothelin-1 (ET-1), adhesion molecules like VCAM-1, M1 macrophage markers, and decreased M2 macrophage markers, eNOS expression, and nitrite levels in aortas, were also observed. VA (50 mg/kg, 14 days, i. p.) was administered to mice following 8 weeks of CUS exposure until the end of the experimental procedure. VA significantly prevented the decrease in BDNF, eNOS and nitrite levels, reduced lesion formation and fibrosis in thoracic aortas and increased ET-1, and VCAM-1 followed by M2 polarization in VA-treated mice. The study highlights the potential of epigenetic modulation of BDNF as a therapeutic target, in stress-induced cardiovascular pathologies and suggests that VA could be a promising agent for mitigating CUS-induced endothelial dysfunction and atherosclerosis by BDNF modulation., Competing Interests: Declaration of competing interest The authors declared no potential conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Preeclampsia is a hypertensive disorder of pregnancy marked by vascular dysfunction, large artery stiffness, and excess oxidized low-density lipoprotein (oxLDL). oxLDL activates oxidative stress pathways which contribute to arterial stiffness through interaction with the lectin-like oxLDL receptor 1 (LOX-1). Increased vascular stiffness is associated with higher pulse wave velocity and downstream microvasculature damage. Here we evaluated the ability of LOX-1 inhibition (LOX-1i) to prevent large artery structural and microvascular structural and functional changes via assessment of the descending thoracic aorta (DTAo) and posterior cerebral arteries (PCA) in a high cholesterol model of preeclampsia. Adult female Sprague Dawley normal late-pregnant (LP) and experimentally preeclamptic (ePE, high cholesterol diet d7-19) animals underwent intraperitoneal (i.p.) implantation of a mini-osmotic pump at d12 containing LOX-1 neutralizing antibodies (ePE + LOX-1i, n = 7) or goat IgG as vehicle control (LP + IgG, n = 8 and ePE + IgG, n = 8). Animals were studied at d19. DTAos and PCAs were removed for histologic assessment and isolated vessel experiments, respectively. Fetuses and placentas were weighed individually. Plasma was analyzed for markers of oxidative stress. ePE + IgG DTAo elastin content (an indirect metric of stiffness) was not significantly different from the LP + IgG group. Nonetheless, trending elastin break and sinuosity data (higher number of breaks and lower sinuosity in the ePE + IgG group compared to LP + IgG) suggested increased stiffness in this high cholesterol PE model. LOX-1i appeared to prevent a decrease in elastin. PCAs showed no structural changes with ePE or LOX-1i. ePE PCAs had increased reactivity to the nitric oxide donor sodium nitroprusside and decreased tone that was unaffected by LOX-1i. ePE animals had increased plasma oxLDL and 3-nitrotyrosine that was unaffected by LOX-1i. Taken together, LOX-1i may improve large artery stiffness without mitigation of the oxidative stress or cerebral microvascular dysfunction seen in ePE. Understanding these mechanisms is important in abating the long-term risks of preeclampsia., (© 2024. The Author(s), under exclusive licence to Society for Reproductive Investigation.)

Background: Thoracic aortic dissection (TAD) is an irreversible cardiovascular disorder with high mortality and morbidity. However, the molecular mechanisms remain elusive. Thus, identifying an effective therapeutic target to prevent TAD is especially critical. The purpose of this study is to elucidate the potential mechanism of inflammation and vascular smooth muscle cell (VSMCs) phenotypic switch in β-aminopropionitrile fumarate (BAPN)-induced TAD., Methods: A mouse model of TAD induced by BAPN and IL-1β -stimulated HVSMCs in vivo and in vitro models, respectively. ACE2 Knockdown mice treated with BAPN or without, and the TAD mouse model was treated with or without AAV-ACE2. Transthoracic ultrasound was conducted for assessment the maximum internal diameter of the thoracic aorta arch. RNA sequencing analysis was performed to recapitulate transcriptome profile changes. Western blot were used to detect the expression of MMP2, MMP9, ACE2, SIRT3, OPN, SM22α and other inflammatory markers. The circulating levels of ACE2 was measured by ELISA assay. Histological changes of thoracic aorta tissues were assessed by H&E, EVG and IHC analysis., Results: We found that circulating levels of and the protein levels of ACE2 were increased in the TAD mouse model and in patients with TAD. For further evidence, ACE2 deficiency decelerated the formation of TAD. However, overexpression of ACE2 aggravated BAPN-induced aortic injury and VSMCs phenotypic switch via lowered SIRT3 expression and elevated inflammatory cytokine expression., Conclusion: ACE2 deficiency prevented the development of TAD by inhibiting inflammation and VSMCs phenotypic switch in a SIRT3-dependent manner, suggesting that the ACE2/SIRT3 signaling pathway played a pivotal role in the pathological process of TAD and might be a potential therapeutical target., (© 2024. The Author(s).)

Perivascular adipose tissue (PVAT) negatively regulates vascular muscle contraction. However, in the context of obesity, the PVAT releases vasoconstrictor substances that detrimentally affect vascular function. A pivotal player in this scenario is the peptide endothelin-1 (ET-1), which induces oxidative stress and disrupts vascular function. The present study postulates that obesity augments ET-1 production in the PVAT, decreases the function of the nuclear factor erythroid 2-related factor-2 (Nrf2) transcription factor, further increasing reactive oxygen species (ROS) generation, culminating in PVAT dysfunction. Male C57BL/6 mice were fed either a standard or a high-fat diet for 16 weeks. Mice were also treated with saline or a daily dose of 100 mg·kg-1 of the ETA and ETB receptor antagonist Bosentan, for 7 days. Vascular function was evaluated in thoracic aortic rings, with and without PVAT. Mechanistic studies utilized PVAT from all groups and cultured WT-1 mouse brown adipocytes. PVAT from obese mice exhibited increased ET-1 production, increased ECE1 and ETA gene expression, loss of the anticontractile effect, as well as increased ROS production, decreased Nrf2 activity, and downregulated expression of Nrf2-targeted antioxidant genes. PVAT of obese mice also exhibited increased expression of Tyr216-phosphorylated-GSK3β and KEAP1, but not BACH1 - negative Nrf2 regulators. Bosentan treatment reversed all these effects. Similarly, ET-1 increased ROS generation and decreased Nrf2 activity in brown adipocytes, events mitigated by BQ123 (ETA receptor antagonist). These findings place ET-1 as a major contributor to PVAT dysfunction in obesity and highlight that pharmacological control of ET-1 effects restores PVAT's cardiovascular protective role., (© 2024 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

Aim: This study aimed to investigate the phenolic composition, antioxidant capacity, and toxicity of aqueous extracts of Calamintha nepeta L. leaves and their potential vasorelaxant effects., Methods: Aqueous extracts of Calamintha nepeta L. were prepared by three extraction methods: decoction, infusion, and maceration. The total phenolic contents of the extracts and their antioxidant properties were investigated. The toxicity was evaluated by Artemia salina lethality bioassay. The decoction extract was analyzed by HPLC for its chemical profile and was also used to evaluate the vasorelaxant effect on thoracic aortic rings isolated from healthy Sprague Dawley rats. Pre-contraction was induced by phenylephrine, followed by cumulative doses of the extract (0.001 up to 250 µg/ml)., Results: Aqueous extracts of Calamintha nepeta L. showed noticeable radical scavenging and chelating activities. However, the decoction extract exhibited the most powerful antioxidant capacity. No toxicity was recorded for the extracts obtained by decoction and infusion. Caffeic acid, quercetin, and rosmarinic acid were the main identified compounds. Notably, the aqueous extract obtained by decoction induced significant relaxation in endothelium-intact aortic rings at lower concentrations, and at higher concentrations in denuded aortic rings., Conclusion: This study reveals that Calamintha nepeta L. extracted with a decoction method possesses potent antioxidant capacity and has an endothelium-dependent vasorelaxant effect., Competing Interests: The authors declare that they have no financial interests or personal relationships with other people or organizations that could have influenced the work reported in this paper.

Background: In early atherosclerosis, circulating LDLs (low-density lipoproteins) traverse individual endothelial cells by an active process termed transcytosis. The CANTOS trial (Canakinumab Antiinflammatory Thrombosis Outcome Study) treated advanced atherosclerosis using a blocking antibody for IL-1β (interleukin-1β); this significantly reduced cardiovascular events. However, whether IL-1β regulates early disease, particularly LDL transcytosis, remains unknown., Methods: We used total internal reflection fluorescence microscopy to quantify transcytosis by human coronary artery endothelial cells exposed to IL-1β. To investigate transcytosis in vivo, we injected wild-type and knockout mice with IL-1β and LDL to visualize acute LDL deposition in the aortic arch., Results: Exposure to picomolar concentrations of IL-1β induced transcytosis of LDL but not of albumin by human coronary artery endothelial cells. Surprisingly, expression of the 2 known receptors for LDL transcytosis, ALK-1 (activin receptor-like kinase-1) and SR-BI (scavenger receptor BI), was unchanged or decreased. Instead, IL-1β increased the expression of the LDLR (LDL receptor); this was unexpected because LDLR is not required for LDL transcytosis. Overexpression of LDLR had no effect on basal LDL transcytosis. However, knockdown of LDLR abrogated the effect of IL-1β on transcytosis rates while the depletion of Cav-1 (caveolin-1) did not. Since LDLR was necessary but overexpression had no effect, we reasoned that another player must be involved. Using public RNA sequencing data to curate a list of Rab (Ras-associated binding) GTPases affected by IL-1β, we identified Rab27a. Overexpression of Rab27a alone had no effect on basal transcytosis, but its knockdown prevented induction by IL-1β. This was phenocopied by depletion of the Rab27a effector JFC1 (synaptotagmin-like protein 1). In vivo, IL-1β increased LDL transcytosis in the aortic arch of wild-type but not Ldlr -/- or Rab27a-deficient mice. The JFC1 inhibitor nexinhib20 also blocked IL-1β-induced LDL accumulation in the aorta., Conclusions: IL-1β induces LDL transcytosis by a distinct pathway requiring LDLR and Rab27a; this route differs from basal transcytosis. We speculate that induction of transcytosis by IL-1β may contribute to the acceleration of early disease., Competing Interests: None.

Substituted catechols include both natural and synthetic compounds found in the environment and foods. Some of them are flavonoid metabolites formed by the gut microbiota which are absorbed afterwards. Our previous findings showed that one of these metabolites, 4-methylcatechol, exerts potent vasorelaxant effects in rats. In the current study, we aimed at testing of its 22 structural congeners in order to find the most potent structure and to investigate the mechanism of action. 3-methoxycatechol (3-MOC), 4-ethylcatechol, 3,5-dichlorocatechol, 4-tert-butylcatechol, 4,5-dichlorocatechol, 3-fluorocatechol, 3-isopropylcatechol, 3-methylcatechol and the parent 4-methylcatechol exhibited high vasodilatory activities on isolated rat aortic rings with EC 50 s ranging from ∼10 to 24 μM. Some significant sex-differences were found. The most potent compound, 3-MOC, relaxed also resistant mesenteric artery but not porcine coronary artery, and decreased arterial blood pressure in both male and female spontaneously hypertensive rats in vivo without affecting heart rate. It potentiated the vasodilation mediated by cAMP and cGMP, but did not impact L-type Ca 2+ -channels. By using two inhibitors, activation of voltage-gated potassium channels (K V ) was found to be involved in the mechanism of action. This was corroborated by docking analysis of 3-MOC with the K V 7.4 channel. None of the most active catechols decreased the viability of the A-10 rat embryonic thoracic aorta smooth muscle cell line. Our findings showed that various catechols can relax vascular smooth muscles and hence could provide templates for developing new antihypertensive vasodilator agents without affecting coronary circulation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Background: One of the most recent hormones to be identified and isolated is irisin, extracted from mouse skeletal muscle in 2012. Irisin has been proven to alter blood pressure, which has an impact on blood vessels, enhance endothelial functions, and prevent injury to endothelial cells. The current study aimed to study the effect of irisin on the ultrastructure of the rat thoracic aorta using the transmission electron microscope (TEM)., Materials and Methods: Twenty female rats were recruited for this study and divided into a control group (non-injected), and four experimental groups (injected groups) each consisting of 4 rats. The experimental groups were injected intraperitoneally with different doses of irisin (250ng/mL, 500ng/mL, 1000ng/mL, and 2000ng/mL) twice a week for 4weeks. Then, the descending thoracic aorta of all experimental rats were resected and proceeded with imaging., Results: The results of this study showed a change in the thickness of the tunica intima, internal elastic lamina, elastic lamellae, and external elastic lamina concerning increasing injected irisin concentration. While there was a significant increase in the thickness of tunica media (P<0.0001) and smooth muscle cells (P<0.05). Also, the results showed a significant increase in the number of elastic lamellae in the tunica media (P<0.0001)., Conclusion: Irisin had a major impact on the elasticity of the rat thoracic aorta wall, suggesting that it influences the growth factors of the wall and activates smooth muscle cells in addition to endothelial cells., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Apigenin and baicalein are structurally related flavonoids that have been reported to have multiple pharmacological activities. The aim of this study was to investigate the protective effects and potential mechanisms of apigenin and baicalein in D-galactose-induced aging rats. First, apigenin and baicalein showed remarkable antioxidant activity and anti-glycation activity in vitro. Secondly, the protective effects of apigenin and baicalein on aging rats were investigated. We found that apigenin and baicalein supplementation significantly ameliorated aging-related changes such as declines in the spatial learning and memory and histopathological damage of the hippocampus and thoracic aorta. In addition, our data showed that apigenin and baicalein alleviated oxidative stress as illustrated by decreasing MDA level, increasing SOD activity and GSH level. Further data showed that they significantly reduced the accumulation of advanced glycation end products (AGEs), inhibited the expression of RAGE, down-regulated phosphorylated nuclear factor (p-NF-κB (p65)). Our results suggested that the protective effects of apigenin and baicalein on aging rats were at least partially related to the inhibition of AGEs/RAGE/NF-κB pathway and the improvement of oxidative damage. Overall, apigenin and baicalein showed almost equal anti-aging efficacy. Our results provided an experimental basis for the application of apigenin and baicalein to delay the aging process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The increased incidence of hypertension associated with obstructive sleep apnea (OSA) presents significant physical, psychological, and economic challenges. Peroxisome proliferator-activated receptor gamma (PPARγ) plays a role in both OSA and hypertension, yet the therapeutic potential of PPARγ agonists and antagonists for OSA-related hypertension remains unexplored. Therefore, we constructed a chronic intermittent hypoxia (CIH)-induced hypertension rat model that mimics the pathogenesis of OSA-related hypertension in humans. The model involved administering PPARγ agonist rosiglitazone (RSG), PPARγ antagonist GW9662, or normal saline, followed by regular monitoring of blood pressure and thoracic aorta analysis using staining and electron microscopy. Intriguingly, our results indicated that both RSG and GW9662 appeared to potently counteract CIH-induced hypertension. In silico study suggested that GW9662's antihypertensive effect might mediated through angiotensin II receptor type 1 (AGTR1). Our findings provide insights into the mechanisms of OSA-related hypertension and propose novel therapeutic targets., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The prevention of obesity represents a major health and socio-economic challenge. Nutraceuticals are regularly highlighted for their beneficial effects in preventing the metabolic disturbances associated with obesity. However, few studies have described the combined action of nutraceutical mixtures combining polyphenols with alkaloids., Objective: The aim of this study was to evaluate the effects of long-term dietary supplementation with a mixture of Berberine, Citrus and Apple extracts (BCA) in the primary prevention of obesity and its metabolic and vascular complications in the obese Zucker rat, a spontaneous model of genetic obesity and insulin resistance., Methods: Sixteen 8-week-old obese Zucker male rats were randomly divided into two groups: all rats received oral gavage daily either with water, untreated obese (U-ObZ) or BCA (BCA-ObZ) mixture for thirteen weeks. Morphological and metabolic parameters were measured along the study. Cumulative concentration-response curves to insulin, acetylcholine and phenylephrine were determined on isolated thoracic aorta. Colon permeability measurements were performed using the Ussing chamber technique. Fecal samples collected at the beginning and the end of the protocol were used as a template for amplification of the V3-V4 region of the 16S rDNA genes., Results: BCA supplementation reduced weight gain (p<0.05) and food intake (p<0.05) in the BCA-ObZ group rats compared to the U-ObZ group rats. It also improved glucose tolerance (p<0.001) and decreased fasting insulin and Homeostasis model assessment index (p<0.05). Through ex vivo experiments, the BCA mixture enhanced significantly aortic insulin relaxation (p<0.01), reduced α1-adrenoceptor-mediated vasoconstriction (p<0.01), and decreased distal colon permeability. Moreover, short-chain fatty acid producers such as Bacteroides, Blautia, and Akkermansia were found to be increased by the BCA mixture supplementation., Conclusion: The results showed that a 13-week-supplementation with BCA mixture prevented weight gain and improved glucose metabolism in obese Zucker rats. We also demonstrated that BCA supplementation improved vascular function, colonic barrier permeability and gut microbiota profile., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Siliman Misha et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Torilis japonica (TJ) fruit, is a herb that is traditionally used for erectile dysfunction (ED). Given the shared mechanisms of ED and hypertension through vascular smooth muscle, we hypothesized that TJ would be effective in vasodilation and blood pressure reduction. This study confirmed the authenticity of TJ samples via DNA barcoding and quantified the main active compound, torilin, using HPLC. TJ was extracted with distilled water (TJW) and 50% ethanol (TJE), yielding torilin contents of 0.35 ± 0.01% and 2.84 ± 0.02%, respectively. Ex vivo tests on thoracic aortic rings from Sprague-Dawley rats showed that TJE (3-300 µg/mL) induced endothelium-independent, concentration-dependent vasodilation, unlike TJW. Torilin caused concentration-dependent relaxation with an EC 50 of 210 ± 1.07 µM. TJE's effects were blocked by a voltage-dependent K + channel blocker and alleviated contractions induced by CaCl 2 and angiotensin II. TJE inhibited vascular contraction induced by phenylephrine or KCl via extracellular CaCl 2 and enhanced inhibition with nifedipine, indicating involvement of voltage-dependent and receptor-operated Ca 2+ channels. Oral administration of TJE (1000 mg/kg) significantly reduced blood pressure in spontaneously hypertensive rats. These findings suggest TJ extract's potential for hypertension treatment through vasorelaxant mechanisms, though further research is needed to confirm its efficacy and safety.

Background: β-aminopropionitrile (BAPN) is a pharmacological inhibitor of LOX (lysyl oxidase) and LOXLs (LOX-like proteins). Administration of BAPN promotes aortopathies, although there is a paucity of data on experimental conditions to generate pathology. The objective of this study was to define experimental parameters and determine whether equivalent or variable aortopathies were generated throughout the aortic tree during BAPN administration in mice., Methods: BAPN was administered in drinking water for a period ranging from 1 to 12 weeks. The impacts of BAPN were first assessed with regard to BAPN dose, and mouse strain, age, and sex. BAPN-induced aortic pathological characterization was conducted using histology and immunostaining. To investigate the mechanistic basis of regional heterogeneity, the ascending and descending thoracic aortas were harvested after 1 week of BAPN administration before the appearance of overt pathology., Results: BAPN-induced aortic rupture predominantly occurred or originated in the descending thoracic aorta in young C57BL/6J or N mice. No apparent differences were found between male and female mice. For mice surviving 12 weeks of BAPN administration, profound dilatation was consistently observed in the ascending region, while there were more heterogeneous changes in the descending thoracic region. Pathological features were distinct between the ascending and descending thoracic regions. Aortic pathology in the ascending region was characterized by luminal dilatation and elastic fiber disruption throughout the media. The descending thoracic region frequently had dissections with false lumen formation, collagen deposition, and remodeling of the wall surrounding the false lumen. Cells surrounding the false lumen were predominantly positive for α-SMA (α-smooth muscle actin). One week of BAPN administration compromised contractile properties in both regions equivalently, and RNA sequencing did not show obvious differences between the 2 aortic regions in smooth muscle cell markers, cell proliferation markers, and extracellular components., Conclusions: BAPN-induced pathologies show distinct, heterogeneous features within and between ascending and descending aortic regions in mice., Competing Interests: Disclosures None.

Background: The specific mechanism by which rotenone impacts thoracic aortic autophagy and apoptosis is unknown. We aimed to investigate the regulatory effects of rotenone on autophagy and apoptosis in rat thoracic aortic endothelial cells (RTAEC) via activation of the LKB1-AMPK-ULK1 signaling pathway and to elucidate the molecular mechanisms of rotenone on autophagy and apoptosis in vascular endothelial cells., Methods: In vivo, 60 male SD rats were randomly selected and divided into 5 groups: control (Con), DMSO, 1, 2, and 4 mg/kg groups, respectively. After 28 days of treatment, histopathological and ultrastructural changes in each group were observed using HE and transmission electron microscopy; Autophagy, apoptosis, and LKB1-AMPK-ULK1 pathway-related proteins were detected by Western blot; Apoptosis levels in the thoracic aorta were detected by TUNEL. In vitro, RTAEC were cultured and divided into control (Con), DMSO, 20, 100, 500, and 1000 nM groups. After 24 h of intervention, autophagy, apoptosis, and LKB1-AMPK-ULK1 pathway-related factors were detected by Western blot and qRT-PCR; Flow cytometry to detect apoptosis levels; Autophagy was inhibited with 3-MA and CQ to detect apoptosis levels, and changes in autophagy, apoptosis, and downstream factors were detected by the AMPK inhibitor CC intervention., Results: Gavage in SD rats for 28 days, some degree of damage was observed in the thoracic aorta and heart of the rotenone group, as well as the appearance of autophagic vesicles was observed in the thoracic aorta. TUNEL analysis revealed higher apoptosis in the rotenone group's thoracic aorta; RTAEC cultured in vitro, after 24 h of rotenone intervention, showed increased ROS production and significantly decreased ATP production. The flow cytometry data suggested an increase in the number of apoptotic RTAEC. The thoracic aorta and RTAEC in the rotenone group displayed elevated levels of autophagy and apoptosis, and the LKB1-AMPK-ULK1 pathway proteins were activated and expressed at higher levels. Apoptosis and autophagy were both suppressed by the autophagy inhibitors 3-MA and CQ. The AMPK inhibitor CC reduced autophagy and apoptosis in RTAEC and suppressed the production of the AMPK downstream factors ULK1 and P-ULK1., Conclusions: Rotenone may promote autophagy in the thoracic aorta and RTAEC by activating the LKB1-AMPK-ULK1 signaling pathway, thereby inducing apoptosis., (© 2024. The Author(s).)

Cardiovascular outcome in Marfan syndrome (MFS) patients most prominently depends on aortic aneurysm progression with subsequent aortic dissection. Angiotensin II receptor blockers (ARBs) prevent aneurysm formation in MFS mouse models. In patients, ARBs only slow down aortic dilation. Downstream signalling from the angiotensin II type 1 receptor (AT1R) is mediated by G proteins and β-arrestin recruitment. AT1R also interacts with the monocyte chemoattractant protein-1 (MCP-1) receptor, resulting in inflammation. In this study, we explore the targeting of β-arrestin signalling in MFS mice by administering TRV027. Furthermore, because high doses of the ARB losartan, which has been proven beneficial in MFS, cannot be achieved in humans, we investigate a potential additive effect by combining lower concentrations of losartan (25 mg/kg/day and 5 mg/kg/day) with barbadin, a β-arrestin blocker, and DMX20, a C-C chemokine receptor type 2 (CCR2) blocker. A high dose of losartan (50 mg/kg/day) slowed down aneurysm progression compared to untreated MFS mice (1.73 ± 0.12 vs. 1.96 ± 0.08 mm, p = 0.0033). TRV027, the combination of barbadin with losartan (25 mg/kg/day), and DMX-200 (90 mg/kg/day) with a low dose of losartan (5 mg/kg/day) did not show a significant beneficial effect. Our results confirm that while losartan effectively halts aneurysm formation in Fbn1 C1041G/+ MFS mice, neither TRV027 alone nor any of the other compounds combined with lower doses of losartan demonstrate a notable impact on aneurysm advancement. It appears that complete blockade of AT1R function, achieved by administrating a high dosage of losartan, may be necessary for inhibiting aneurysm progression in MFS.

Abstract: Studies have examined the therapeutic effect of levosimendan on cardiovascular diseases such as heart failure, perioperative cardiac surgery, and septic shock, but the specific mechanism in mice remains largely unknown. This study aimed to investigate the relaxation mechanism of levosimendan in the thoracic aorta smooth muscle of mice. Levosimendan-induced relaxation of isolated thoracic aortic rings that were precontracted with norepinephrine or KCl was recorded in an endothelium-independent manner. Vasodilatation by levosimendan was not associated with the production of the endothelial relaxation factors nitric oxide and prostaglandins. The voltage-dependent K + channel (K V ) blocker (4-aminopyridine) and selective K Ca blocker (tetraethylammonium) had no effect on thoracic aortas treated with levosimendan, indicating that K V and K Ca channels may not be involved in the levosimendan-induced relaxation mechanism. Although the inwardly rectifying K + channel (K ir ) blocker (barium chloride) and the K ATP channel blocker (glibenclamide) significantly inhibited levosimendan-induced vasodilation in the isolated thoracic aorta, barium chloride had a much stronger inhibitory effect on levosimendan-induced vasodilation than glibenclamide, suggesting that levosimendan-induced vasodilation may be mediated by K ir channels. The vasodilation effect and expression of K ir 2.1 induced by levosimendan were further enhanced by the PKC inhibitor staurosporine. Extracellular calcium influx was inhibited by levosimendan without affecting intracellular Ca 2+ levels in the isolated thoracic aorta. These results suggest that K ir channels play a more important role than K ATP channels in regulating vascular tone in larger arteries and that the activity of the K ir channel is enhanced by the PKC pathway., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Long-term β-adrenoceptor (β-AR) stimulation is a pathological mechanism associated with cardiovascular diseases resulting in endothelial and perivascular adipose tissue (PVAT) dysfunction. In this study, we aimed to identify whether β-adrenergic signaling has a direct effect on PVAT. Thoracic aorta PVAT was obtained from male Wistar rats and cultured ex vivo with the β-AR agonist isoproterenol (Iso; 1 µM) or vehicle for 24 hours. Conditioned culture medium (CCM) from Iso-treated PVAT induced a marked increase in aorta contractile response, induced oxidative stress, and reduced nitric oxide production in PVAT compared to vehicle. In addition, Iso-treated PVAT and PVAT-derived differentiated adipocytes exhibited higher corticosterone release and protein expression of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), an enzyme responsible for de novo synthesis of corticosterone. Macrophages exposed to Iso also exhibited increased corticosterone release in response to β-AR stimulation. Incubation of Iso-treated PVAT and PVAT-derived differentiated adipocytes with β3-AR antagonist restored aorta contractile function modulated by Iso-CCM and normalized 11β-HSD1 protein expression. These results show that β3-AR signaling leads to upregulation of 11β-HSD1 in PVAT, thus increasing corticosterone release and contributing to impair the anticontractile function of this tissue., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: Vascular dysfunction constitutes the etiology of many diseases, such as myocardial infarction and hypertension, with the disruption of redox homeostasis playing a role in the imbalance of the vasomotor control mechanism. Our group previously has shown that thyroid hormones exert protective effects on the aortic tissue of infarcted rats by improving angiogenesis signaling., Objective: Investigate the role of triiodothyronine (T3) on vascular response, exploring its effects on isolated aortas and whether there is an involvement of vascular redox mechanisms., Methods: Isolated aortic rings (intact- and denuded-endothelium) precontracted with phenylephrine were incubated with T3 (10-8, 10-7, 10-6, 10-5, and 10-4 M), and tension was recorded using a force-displacement transducer coupled with an acquisition system. To assess the involvement of oxidative stress, aortic rings were preincubated with T3 and subsequently submitted to an in vitro reactive oxygen species (ROS) generation system. The level of significance adopted in the statistical analysis was 5%., Results: T3 (10-4 M) promoted vasorelaxation of phenylephrine precontracted aortic rings in both intact- and denuded-endothelium conditions. Aortic rings preincubated in the presence of T3 (10-4 M) also showed decreased vasoconstriction elicited by phenylephrine (1 µM) in intact-endothelium preparations. Moreover, T3 (10-4 M) vasorelaxation effect persisted in aortic rings preincubated with NG-nitro-L-arginine methylester (L-NAME, 10 µM), a nonspecific NO synthase (NOS) inhibitor. Finally, T3 (10-4 M) exhibited, in vitro, an antioxidant role by reducing NADPH oxidase activity and increasing SOD activity in the aorta's homogenates., Conclusion: T3 exerts dependent- and independent-endothelium vasodilation effects, which may be related to its role in maintaining redox homeostasis.

Background: The pineal product melatonin (MEL) modulates blood vessels through G protein-coupled receptors (GPCRs) called melatonin type 1 receptor (MT 1 R) and melatonin type 2 receptor (MT 2 R), in that order. The renin-angiotensin system (RAS), which breaks down angiotensin II (Ang II) to create Ang 1-7, is thought to be mostly controlled by angiotensin-converting enzyme-2 (ACE 2 )., Aim: The current work examines the involvement of ACE 2 inhibitor, MEL, and ramelteon (RAM) in the vascular response to Ang II activities in the endothelial denuded (E-) and intact (E+) rat isolated thoracic aortic rings., Method: The isometric tension was measured to evaluate the vascular Ang II contractility using dose response curve (DRC)., Results: MEL and RAM caused a rightward shift of Ang II in endothelium E + and endothelium E- aorta., Conclusion: According to the current study, the distribution of MEL receptors and the endothelium's condition are related to the vasomodulatory effect of MEL and ACE 2 on Ang II attenuation. These physiological interactions can control vascular tone and increase Ang II reactivity denude endothelial layaer.

Objective: To investigate the pharmacological effects and molecular mechanisms of lanthanum hydroxide(LH) on ectopic mineralization of soft tissue and abnormal bone in rats with acute kidney injury(AKI)., Methods: Wistar rats were modeled by 5/6 nephrectomy. After the operation, the rats were divided into different groups, the biochemical indexes of serum collected at different times. LH was administered by intragastric tube at doses of 0.4, 0.2, and 0.1g/kg, respectively. Rats were sacrificed in the 16th week after LH treatment. Observation of pathological changes in tissues were made by specific staining. Western Blot, Real-Time Quantitative PCR, and immunohistochemistry techniques were used to detect the impact on pathway-related proteins., Results: Compared with the control group (no LH administered), the serum phosphate level of the LH group was significantly reduced (p<0.01), calcification of the thoracic aorta was reduced (p<0.05, p<0.01) (Serum biochemical tests before dosing and during drug treatment cycles), renal fibrosis was improved (p<0.01), nuclear entry of nuclear factor kappa-B (NF-κB) was reduced (p<0.01), and the expression of the smooth muscle protein 22α (SM22α) was significantly increased (p<0.01). The expression of osteogenic marker genes was decreased. In addition, compared with the controls, the receptor activator for nuclear factor-κB ligand/osteoprotegerin (RANKL/OPG) ratio of the femur in the model group was increased (p<0.05)., Conclusion: LH can inhibit the occurrence and development of vascular calcification and bone abnormalities in AKI rats by inhibiting the NF-κB and RANKL/OPG signaling pathways., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Cigarette smoking remains the leading modifiable risk factor for cardiopulmonary diseases; however, the effects of nicotine alone on cardiopulmonary function remain largely unknown. Previously, we have shown that chronic nicotine vapor inhalation in mice leads to the development of pulmonary hypertension (PH) with right ventricular (RV) remodeling. The present study aims to further examine the cardiopulmonary effects of nicotine and the role of the α7 nicotinic acetylcholine receptor (α7-nAChR), which is widely expressed in the cardiovascular system. Wild-type (WT) and α7-nAChR knockout (α7-nAChR-/-) mice were exposed to room air (control) or nicotine vapor daily for 12 weeks. Consistent with our previous study, echocardiography and RV catheterization reveal that male WT mice developed increased RV systolic pressure with RV hypertrophy and dilatation following 12-week nicotine vapor exposure; in contrast, these changes were not observed in male α7-nAChR-/- mice. In addition, chronic nicotine inhalation failed to induce PH and RV remodeling in female mice regardless of genotype. The effects of nicotine on the vasculature were further examined in male mice. Our results show that chronic nicotine inhalation led to impaired acetylcholine-mediated vasodilatory response in both thoracic aortas and pulmonary arteries, and these effects were accompanied by altered endothelial nitric oxide synthase phosphorylation (enhanced inhibitory phosphorylation at threonine 495) and reduced plasma nitrite levels in WT but not α7-nAChR-/- mice. Finally, RNA sequencing revealed up-regulation of multiple inflammatory pathways in thoracic aortas from WT but not α7-nAChR-/- mice. We conclude that the α7-nAChR mediates chronic nicotine inhalation-induced PH, RV remodeling and vascular dysfunction., (© 2022 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

Vascular calcification (VC) is characterized by pathological depositions of calcium and phosphate in the arteries and veins via an active cell-regulated process, in which vascular smooth muscle cells (VSMCs) transform into osteoblast/chondrocyte-like cells as in bone formation. VC is associated with significant morbidity and mortality in chronic kidney disease (CKD) and cardiovascular disease, but the underlying mechanisms remain unclear. In this study we investigated the role of large-conductance calcium-activated potassium (BK) channels in 3 experimental VC models. VC was induced in vascular smooth muscle cells (VSMCs) by β-glycerophosphate (β-GP), or in rats by subtotal nephrectomy, or in mice by high-dosage vitamin D3. We showed that the expression of BK channels in the artery of CKD rats with VC and in β-GP-treated VSMCs was significantly decreased, which was functionally confirmed by patch-clamp recording. In β-GP-treated VSMCs, BK channel opener NS1619 (20 μM) significantly alleviated VC by decreasing calcium content and alkaline phosphatase activity. Furthermore, NS1619 decreased mRNA expression of ostoegenic genes OCN and OPN, as well as Runx2 (a key transcription factor involved in preosteoblast to osteoblast differentiation), and increased the expression of α-SMA protein, whereas BK channel inhibitor paxilline (10 μM) caused the opposite effects. In primary cultured VSMCs from BK -/- mice, BK deficiency aggravated calcification as did BK channel inhibitor in normal VSMCs. Moreover, calcification was more severe in thoracic aorta rings of BK -/- mice than in those of wild-type littermates. Administration of BK channel activator BMS191011 (10 mg· kg -1  ·d -1 ) in high-dosage vitamin D3-treated mice significantly ameliorated calcification. Finally, co-treatment with Akt inhibitor MK2206 (1 μM) or FoxO1 inhibitor AS1842856 (3 μM) in calcified VSMCs abrogated the effects of BK channel opener NS1619. Taken together, activation of BK channels ameliorates VC via Akt/FoxO1 signaling pathways. Strategies to activate BK channels and/or enhance BK channel expression may offer therapeutic avenues to control VC., (© 2021. The Author(s), under exclusive licence to CPS and SIMM.)

Aortic dissection (AD) is a disease with high mortality and lacks effective drug treatment. Recent studies have shown that the development of AD is closely related to glucose metabolism. Lactate dehydrogenase A (LDHA) is a key glycolytic enzyme and plays an important role in cardiovascular disease. However, the role of LDHA in the progression of AD remains to be elucidated. Here, we found that the level of LDHA was significantly elevated in AD patients and the mouse model established by BAPN combined with Ang II. In vitro, the knockdown of LDHA reduced the growth of human aortic vascular smooth muscle cells (HAVSMCs), glucose consumption, and lactate production induced by PDGF-BB. The overexpression of LDHA in HAVSMCs promoted the transformation of HAVSMCs from contractile phenotype to synthetic phenotype, and increased the expression of MMP2/9. Mechanistically, LDHA promoted MMP2/9 expression through the LDHA-NDRG3-ERK1/2-MMP2/9 pathway. In vivo, Oxamate, LDH and lactate inhibitor, reduced the degradation of elastic fibers and collagen deposition, inhibited the phenotypic transformation of HAVSMCs from contractile phenotype to synthetic phenotype, reduced the expression of NDRG3, p-ERK1/2, and MMP2/9, and delayed the progression of AD. To sum up, the increase of LDHA promotes the production of MMP2/9, stimulates the degradation of extracellular matrix (ECM), and promoted the transformation of HAVSMCs from contractile phenotype to synthetic phenotype. Oxamate reduced the progression of AD in mice. LDHA may be a therapeutic target for AD., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The uremic toxin indoxyl sulfate (IS), elevated in chronic kidney disease (CKD), is known to contribute towards progressive cardiovascular disease. IS activates the aryl hydrocarbon receptor (AhR) mediating oxidative stress and endothelial dysfunction via activation of the CYP1A1 pathway. The present study examines AhR inhibition with the antagonist, CH223191, on IS-mediated impairment of vascular endothelial function and disruption of redox balance. The acute effects of IS on endothelium-dependent relaxation were assessed in aortic rings from Sprague Dawley rats exposed to the following conditions: (1) control; (2) IS (300 μM); (3) IS + CH223191 (1 μM); (4) IS + CH223191 (10 μM). Thereafter, tissues were assessed for changes in expression of redox markers. IS reduced the maximum level of endothelium-dependent relaxation (Rmax) by 42% ( p < 0.001) compared to control, this was restored in the presence of increasing concentrations of CH223191 ( p < 0.05). Rings exposed to IS increased expression of CYP1A1, nitro-tyrosine, NADPH oxidase 4 (NOX4), superoxide, and reduced eNOS expression ( p < 0.05). CH223191 (10 μM) restored expression of these markers back to control levels ( p < 0.05). These findings demonstrate the adverse impact of IS-mediated AhR activation on the vascular endothelium, where oxidative stress may play a critical role in inducing endothelial dysfunction in the vasculature of the heart and kidneys. AhR inhibition could provide an exciting novel therapy for CVD in the CKD setting.

Tributyltin chloride (TBT) is an organotin compound widely used in several high biocides for agroindustrial applications, such as fungicides, and marine antifouling paints leading to endocrine disrupting actions, such as imposex development in mollusks. In female rats, TBT has been shown to promote ovarian dysfunction, reduction of estrogen protective effect in the vascular morphophysiology, at least in part by oxidative stress consequences. Estrogen causes coronary endothelium-dependent and independent vasodilation. However, the TBT effects on cardiovascular system of male rats are not fully understood. The aim of this study was to evaluate the effects of subacute TBT exposure in aorta vascular reactivity from male wistar rats. Rats were randomly divided into three groups: control (C), TBT 500 ng/kg/day and TBT 1000 ng/kg/day. TBT was administered daily for 30 days by oral gavage. We found that TBT exposure enhanced testosterone serum levels and it was also observed obesogenic properties. TBT exposure evoked an increase in endothelium-dependent and independent phenylephrine-induced contraction, associated to an inhibition in eNOS activity. On the other hand, it was observed an enhancement of iNOS and NF-kB protein expression. We also observed an increase in oxidative stress parameters, such as superoxide dismutase (SOD) and catalase expression, and also an increase in malondialdehyde production. Finally, TBT exposure produced aortic intima-media thickness. Taken together, these data suggest a potential cardiovascular toxicological effect after subacute TBT exposure in male rats., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Aims: Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting joints and blood vessels. Despite low levels of low-density lipoprotein cholesterol (LDL-C), RA patients exhibit endothelial dysfunction and are at increased risk of death from cardiovascular complications, but the molecular mechanism of action is unknown. We aimed in the present study to identify the molecular mechanism of endothelial dysfunction in a mouse model of RA and in patients with RA., Methods and Results: Endothelium-dependent relaxations to acetylcholine were reduced in aortae of two tumour necrosis factor alpha (TNFα) transgenic mouse lines with either mild (Tg3647) or severe (Tg197) forms of RA in a time- and severity-dependent fashion as assessed by organ chamber myograph. In Tg197, TNFα plasma levels were associated with severe endothelial dysfunction. LOX-1 receptor was markedly up-regulated leading to increased vascular oxLDL uptake and NFκB-mediated enhanced Arg2 expression via direct binding to its promoter resulting in reduced NO bioavailability and vascular cGMP levels as shown by ELISA and chromatin immunoprecipitation. Anti-TNFα treatment with infliximab normalized endothelial function together with LOX-1 and Arg2 serum levels in mice. In RA patients, soluble LOX-1 serum levels were also markedly increased and closely related to serum levels of C-reactive protein. Similarly, ARG2 serum levels were increased. Similarly, anti-TNFα treatment restored LOX-1 and ARG2 serum levels in RA patients., Conclusions: Increased TNFα levels not only contribute to RA, but also to endothelial dysfunction by increasing vascular oxLDL content and activation of the LOX-1/NFκB/Arg2 pathway leading to reduced NO bioavailability and decreased cGMP levels. Anti-TNFα treatment improved both articular symptoms and endothelial function by reducing LOX-1, vascular oxLDL, and Arg2 levels., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2021. For permissions, please email: journals.permissions@oup.com.)

In this study, we have looked for an optimum media glucose concentration and compared glucose consumption in three vascular cell types, endothelial cells (ECs), vascular smooth muscle cells (VSMCs), and adventitial fibroblasts (AFs) with or without angiotensin II (AngII) stimulation. In a subconfluent 6-well experiment in 1 mL DMEM with a standard low (100 mg/dL), a standard high (450 mg/dL), or a mixed middle (275 mg/dL) glucose concentration, steady and significant glucose consumption was observed in all cell types. After 48-h incubation, media that contained low glucose was reduced to almost 0 mg/dL, media that contained high glucose remained significantly higher at ∼275 mg/dL, and media that contained middle glucose remained closer to physiological range. AngII treatment enhanced glucose consumption in AFs and VSMCs but not in ECs. Enhanced extracellular acidification rate by AngII was also observed in AFs. In AFs, AngII induction of target proteins at 48 h varied depending on the glucose concentration used. In low glucose media, induction of glucose regulatory protein 78 or hexokinase II was highest, whereas induction of VCAM-1 was lowest. Utilization of specific inhibitors further suggests essential roles of angiotensin II type-1 receptor and glycolysis in AngII-induced fibroblast activation. Overall, this study demonstrates a high risk of hypo- or hyperglycemic conditions when standard low or high glucose media is used with vascular cells. Moreover, these conditions may significantly alter experimental outcomes. Media glucose concentration should be monitored during any culture experiments and utilization of middle glucose media is recommended for all vascular cell types.

Endothelial injury plays a vital role in vascular lesions from diabetes mellitus (DM). Therapeutic targets against endothelial damage may provide critical venues for the treatment of diabetic vascular diseases. Peroxisome proliferator-activated receptor β (PPARβ) is a crucial regulator in DM and its complications. However, the molecular signal mediating the roles of PPARβ in DM-induced endothelial dysfunction is not fully understood. The impaired endothelium-dependent relaxation and destruction of the endothelium structures appeared in high glucose incubated rat aortic rings. A high glucose level significantly decreased the expression of PPARβ and endothelial nitric oxide synthase (eNOS) at the mRNA and protein levels, and reduced the concentration of nitric oxide (NO), which occurred in parallel with an increase in the expression of inducible nitric oxide synthase (iNOS) and 3-nitrotyrosine. The effect of high glucose was inhibited by GW0742, a PPARβ agonist. Both GSK0660 (PPARβ antagonist) and N G -nitro-l-arginine-methyl ester (NOS inhibitor) could reverse the protective effects of GW0742. These results suggest that the activation of nitrative stress may, at least in part, mediate the down-regulation of PPARβ in high glucose-impaired endothelial function in rat aorta. PPARβ-nitrative stress may hold potential in treating vascular complications from DM., (Copyright © 2021. Published by Elsevier Inc.)

Irisin, an exercise-induced myokine, has been shown to have a peripheral vasodilator effect. However, little is known about the mechanisms underlying its effects. In this study, it was aimed to investigate the vasoactive effects of irisin on rat thoracic aorta, and the hypothesis that voltage-gated potassium (K V ) channels, ATP-sensitive potassium (K ATP ) channels, small-conductance calcium-activated potassium (SK Ca ) channels, large-conductance calcium-activated potassium (BK Ca ) channels, intermediate-conductance calcium-activated potassium (IK Ca ) channels, inward rectifier potassium (K ir ) channels, and two-pore domain potassium (K 2P ) channels may have roles in these effects. Isometric contraction-relaxation responses of isolated thoracic aorta rings were measured with an organ bath model. The steady contraction was induced with both 10 -5 M phenylephrine and 45 mM KCl, and then the concentration-dependent responses of irisin (10 -9 -10 -6 M) were examined. Irisin exerted the vasorelaxant effects in both endothelium-intact and -denuded aortic rings at concentrations of 10 -8 , 10 -7 , and 10 -6 M (p < 0.001). Besides, K V channel blocker 4-aminopyridine, K ATP channel blocker glibenclamide, SK Ca channel blocker apamin, BK Ca channel blockers tetraethylammonium and iberiotoxin, IK Ca channel blocker TRAM-34, and K ir channel blocker barium chloride incubations significantly inhibited the irisin-induced relaxation responses. However, incubation of K 2P TASK-1 channel blocker anandamide did not cause a significant decrease in the relaxation responses of irisin. In conclusion, the first physiological findings were obtained regarding the functional relaxing effects of irisin in rat thoracic aorta. Furthermore, this study is the first to report that irisin-induced relaxation responses are associated with the activity of K V , K ATP , SK Ca , BK Ca , IK Ca , and K ir channels., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Acitretin is a member of vitamin A-derived retinoids, and its effect on vascular smooth muscle had not yet been studied. The aim of this study is to investigate the effect of acitretin, a retinoid, on vascular smooth muscle contractility. Thoracic aorta preparations obtained from 34 male Sprague-Dawley rats (355 ± 15 g) were studied in isolated organ baths containing Krebs-Henseleit solution. The relaxation responses were obtained with acitretin (10 -12 -10 -4  M) in endothelium-preserved and endothelium-denuded aorta preparations precontracted with submaximal concentration of phenylephrine (10 -6  M). The role of retinoic acid receptors (RARs), nitric oxide, adenylyl, and guanylyl cyclase enzymes, and potassium channels in these relaxation responses were investigated. Acitretin produced concentration-dependent relaxations, which were independent of its solvent dimethylsulfoxide (DMSO), in endothelium-denuded phenylephrine-precontracted thoracic aorta preparations. While incubation with the RAR antagonist (AGN193109, 10 -5  M) had no effect on these relaxations; nitric oxide synthase inhibitor (L-N G -Nitro arginine methyl ester (L-NAME), 10 -4  M), adenylyl cyclase inhibitor (SQ2253, 10 -5  M), guanylyl cyclase inhibitor (oxadiazolo [4,3-a] quinoxalin-1-one (ODQ), 10 -6 M), and potassium channel blocker (tetraethylammonium (TEA), 10 -2  M) significantly eliminated the relaxation responses induced by acitretin. Acitretin induces relaxation in rat isolated thoracic aorta preparations without endothelium, which may be mediated by nitric oxide, cyclic adenosine monophosphate, and cyclic guanosine monophosphate-dependent kinases and potassium channels.

Background: Inflammatory dysregulation of KLF4 is related to atheromatosis. In the present study, we explored the impact of colchicine-based regimens on the development of thoracic aortic atheromatosis and KLF4 expression., Methods: Twenty-eight New Zealand White rabbits were divided to 4 groups. The control group (n = 6) was fed standard chow, group A (n = 6) was fed chow enriched with 1% w/w cholesterol, group B (n = 8) was fed the same cholesterol-enriched diet plus 2 mg/kg body weight/day colchicine and 250 mg/kg body weight/day fenofibrate, while group C (n = 8) was also fed the same diet plus 2 mg/kg body weight/day colchicine and 15 mg/kg body weight/day N-acetylcysteine. After 7 weeks, all animals were euthanized, and their thoracic aortas were isolated. Atherosclerotic plaque area was estimated with morphometric analysis. KLF4 expression was quantified with quantitative RT-PCR., Results: Group A developed significantly more atherosclerosis compared to group B (MD: 13.67, 95% CI: 7.49-19.84) and C (MD: 20.29, 95% CI: 14.12-26.47). Colchicine with N-acetylcysteine resulted in more pronounced reduction in the extent of atherosclerotic plaques compared to colchicine/fibrate (MD: 6.62, 95% CI: 0.90-12.34). Group A exhibited significantly greater KLF4 expression compared to group B (MD: 4.94, 95% CI: 1.11-8.77) and C (MD: 9.94, 95% CI: 6.11-13.77). Combining colchicine with N-acetylcysteine instead of fenofibrate (MD: 5.00, 95% CI: 1.45-8.54) led to a more robust reduction in KLF4 expression., Conclusions: In the present hyperlipidemic animal model, colchicine-based regimens curtailed de novo atherogenesis and KLF4 overexpression in thoracic aortas., (Copyright © 2021. Published by Elsevier Inc.)

Aim: To examine the effect of diacerein on vascular dysfunction in type 2 diabetic rats and elucidate the mechanism of diacerein., Methods: In a rat model, type 2 diabetes was induced by high-fat diet and streptozotocin. Vascular function was assessed in vascular reactivity experiment. The effect of diacerein (10 or 20 mg/kg/day) on blood glucose, inflammation and insulin signaling, and modulators in vascular tissue in diabetic rats were investigated by molecular and biochemical approaches., Results: In this study, diacerein inhibited diabetes-induced vascular dysfunction. Diacerein treatment normalized blood glucose, insulin tolerance test, inflammatory cytokine levels and nitric oxide synthases expression in diabetic rats. Moreover, diacerein inhibited NF-κB and NLRP3 pathways and activated insulin signaling pathway related proteins IRS-1 and AKT in diabetic rats., Conclusion: Diacerein improved vascular function effectively in diabetic rats by suppressing inflammation and reducing insulin resistance. These results suggest that diacerein may represent a novel therapy for patients with diabetes., Competing Interests: Declaration of competing interest All authors read and approved the final version of the manuscript, and agreed to the author's order of statements. The authors declare no conflict of interest., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Angiogenesis, the formation of new blood vessels, underlies tissue development and repair. Some medicinal plant-derived compounds can modulate the angiogenic response. Heliopsis longipes , a Mexican medicinal plant, is widely used because of its effects on pain and inflammation. The main bioactive phytochemicals from H. longipes roots are alkamides, where affinin is the most abundant. Scientific studies show various medical effects of organic extracts of H. longipes roots and affinin that share some molecular pathways with the angiogenesis process, with the vasodilation mechanism of action being the most recent. This study investigates whether pure affinin and the ethanolic extract from Heliopsis longipes roots (HLEE) promote angiogenesis. Using the aortic ring rat assay (ex vivo method) and the direct in vivo angiogenesis assay, where angioreactors were implanted in CD1 female mice, showed that affinin and the HLEE increased vascular growth in a dose-dependent manner in both bioassays. This is the first study showing the proangiogenic effect of H. longipes . Further studies should focus on the mechanism of action and its possible therapeutic use in diseases characterized by insufficient angiogenesis.

Aims: Canagliflozin is an anti-diabetic agent and sodium glucose co-transporter-2 inhibitor. Despite numerous clinical trials demonstrating its beneficial effects on blood pressure, the cellular mechanisms underlying the effects of canagliflozin on vascular reactivity have yet to be clarified. We investigated the vasodilatory effect of canagliflozin on aortic rings isolated from rabbits., Main Methods: We used rabbit thoracic aortic rings and its arterial tone was tested by using wire myography system., Key Findings: Canagliflozin caused concentration-dependent vasodilation in aortic rings pre-constricted with phenylephrine or high K + . However, the degree of canagliflozin-induced vasodilation of the aortic rings pre-constricted with high K + was less than that of rings pre-constricted with phenylephrine. Application of 4-aminopyridine, a voltage-dependent K + (Kv) channel inhibitor, reduced canagliflozin-induced vasodilation. However, pre-incubation of an inwardly rectifying K + channel inhibitor, a large-conductance Ca 2+ -activated K + channel inhibitor, and an ATP-sensitive K + inhibitor did not modulate the vasodilatory effects of canagliflozin. Indeed, canagliflozin increased Kv currents in aortic smooth muscle cells. Pre-treatment with thapsigargin or cyclopiazonic acid, a sarco/endoplasmic reticulum Ca 2+ -ATPase (SERCA) pump inhibitors, reduced the vasodilatory effects of canagliflozin. Conversely, pre-treatment with a Ca 2+ channel inhibitor, adenylyl cyclase/PKA inhibitors, and guanylyl cyclase/PKG inhibitors did not modulate the vasodilatory effects of canagliflozin. Endothelium removal, and pre-treatment with the nitric oxide synthase inhibitor L-NAME, and small- and intermediate-conductance Ca 2+ -activated K + channel inhibitor apamin and TRAM-34, did not diminish the vasodilatory effects of canagliflozin., Significance: Our results indicate that canagliflozin induces vasodilation, which is dependent on the robust SERCA activity and Kv channel activation., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Context: Ginsenoside Rb1 (Rb1) exerts many beneficial effects and protects against cardiovascular disease., Objective: To investigate whether Rb1 could attenuate age-related vascular impairment and identify the mechanism., Materials and Methods: Female C57BL/6J mice aged 2 and 18 months, randomly assigned to Young, Young + 20 mg/kg Rb1, Old + vehicle, Old + 10 mg/kg Rb1 and Old + 20 mg/kg Rb1 groups, were daily intraperitoneal injected with vehicle or Rb1 for 3 months. The thoracic aorta segments were used to inspect the endothelium-dependent vasorelaxation. Left thoracic aorta tissues were collected for histological or molecular expression analyses, including ageing-related proteins, markers relevant to calcification and fibrosis, and expression of Gas6/Axl., Results: We found that in Old + vehicle group, the expression of senescence proteins and cellular adhesion molecules were significantly increased, with worse endothelium-dependent thoracic aorta relaxation (58.35% ± 2.50%) than in Young group (88.84% ± 1.20%). However, Rb1 treatment significantly decreased the expression levels of these proteins and preserved endothelium-dependent relaxation in aged mice. Moreover, Rb1 treatment also reduced calcium deposition, collagen deposition, and the protein expression levels of collagen I and collagen III in aged mice. Furthermore, we found that the downregulation of Gas6 protein expression by 41.72% and mRNA expression by 52.73% in aged mice compared with young mice was abrogated by Rb1 treatment. But there was no significant difference on Axl expression among the groups., Conclusions: Our study confirms that Rb1 could ameliorate vascular injury, suggesting that Rb1 might be a potential anti-ageing related vascular impairment agent.

Abstract: Paracetamol (PAR) is the most common over-the-counter drug recommended by physicians for treatment of pain and fever during gestation. This drug is not teratogenic, being considered safe for fetus; however, PAR crosses the blood-placental barrier. Considering that, the present study aimed to evaluate the vascular and metabolic safety of PAR exposure during intrauterine and neonatal development in adult male and female-exposed offspring. Wistar female rats were gavaged, with PAR (350 mg/kg/d), from gestational day 6-21 or from gestational day 6 until postnatal day 21. Control dams received water by gavage at the same periods. The male and female offspring were evaluated at adulthood (80 days of life). The thoracic aorta reactivity to acetylcholine, sodium nitroprusside, and phenylephrine was evaluated in male and female adult offspring. It was observed that aortic relaxation was similar between the PAR and control offspring. In addition, the contraction to phenylephrine was similar between the groups. Further, the insulin sensitivity, adipose tissue deposition and blood pressure were not different between PAR and control adult offspring. These results suggest that the protocol of PAR exposure used in the present study did not program vascular and metabolic alterations that would contribute to the development of cardiometabolic diseases in adult life, being safe for the exposed offspring., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Context: Gynura bicolour (Roxb. and Willd.) DC (Asteraceae) leaf is a common vegetable. Ethanol extracts of fresh G. bicolour leaves (GBEE) have several physiological effects, but studies on atherosclerosis are limited., Objective: We investigated the oxidant scavenging ability and vascular adhesion molecule expression of these extracts., Materials and Methods: The antioxidant effects of 0.05-0.4 mg/mL GBEE were analyzed in vitro . Intracellular antioxidant capacity and adhesion molecule levels were detected in EA.hy926 cells pre-treated with 10-100 μg/mL GBEE for 8 h, then TNF-α for 3 h. The antioxidant capacity of red blood cells and the adhesion molecule levels in the thoracic aorta were detected in high-fat diet (HFD)-fed Sprague-Dawley rats treated with GBEE for 12 weeks., Results: The in vitro EC 50 values of GBEE based on its DPPH radical-scavenging ability, reducing power, and ferrous ion-chelating ability were 0.20, 3.21 and 0.49 mg/mL, respectively. In TNF-α-treated EA.hy926 cells, the thiobarbituric acid-reactive substance levels were decreased after 10, 50, or 100 μg/mL GBEE treatments (IC 50 : 19.1 mg/mL). When HFD-fed rats were co-treated with GBEE, the GBEE-H group exhibited 25% higher glutathione levels than the HFD group ( p  < 0.05). E-selectin, intercellular adhesion molecule-1, and vascular cell adhesion protein-1 levels were decreased in TNF-α-treated EA.hy926 cells after GBEE treatment (by approximately 11-73%; p  < 0.05), and the above three adhesion molecules levels were decreased in HFD-fed rats with combined GBEE treatment (by approximately 30-77%; p  < 0.05)., Conclusions: GBEE can protect the vascular endothelium by reducing adhesion molecule expression and regulating antioxidants. It may have the potential to prevent atherosclerosis.

Gynura procumbens (GP) is a herbal medicinal plant of South-East Asian origin, popularly recognised as 'Sambung nyawa'. The plant has been used traditionally to treat various diseases including hypertension. The anti-hypertensive activity of this plant has also been scientifically proven both in vivo and in vitro yet the investigation on its mechanisms of actions remains limited. Our previous study has demonstrated the vasodilatory action of both aqueous and methanol GP extracts possibly via activation of the cholinergic pathway and that kaempferol 3-O-rutinoside is the active ingredient responsible in mediating this effect. Hence, in this study we further confirm the involvement of the cholinergic pathway by using several pharmacological interventions, focusing on the downstream mechanism of this pathway. Our results showed that in the presence of endothelium, GP extracts induced vasodilation via activation of the muscarinic M 3 receptors. However, in the absence of endothelium, GP mediated vasodilation possibly via stimulation of other muscarinic receptors and/or involvement of nicotinic receptors, a speculation that needs further investigations. GP-induced relaxation was markedly inhibited by nitric oxide (NO) blocker, L-NAME, suggesting that GP elicited ACh endothelium-dependent relaxation by producing NO in rat aortic rings. In conclusion, these data demonstrate that the vasodilatory effect of GP extracts appears to be mediated via cholinergic pathway., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Alzheimer's disease (AD) has long been considered a brain-specific dementia syndrome. However, in recent decades, the occurrence of cardiovascular (CV) disease in the progression of AD has been confirmed by increasing epidemiological evidence. In this study, we conducted an in-depth cardiovascular characterization of a humanized amyloid precursor protein (APP) overexpressing mouse model (hAPP23 +/- ), which overexpresses the Swedish mutation (KM670/671NL). At the age of 6 mo, hAPP23 +/- mice had a lower survival, lower body weight, and increased corticosterone and VMA levels compared with C57BL/6 littermates. Systolic blood pressure was increased in hAPP23 +/- animals compared with C57BL/6 littermates, but diastolic blood pressure was not statistically different. Pulse pressure remained unchanged but abdominal and carotid pulse-wave velocity (aPWV and cPWV) were increased in hAPP23 +/- compared with C57BL/6 mice. Echocardiography showed no differences in systolic or diastolic cardiac function. Ex vivo evaluation of vascular function showed decreased adreno receptor dependent vasoconstriction of hAPP23 +/- aortic segments, although the isobaric biomechanics of the aortic wall were similar to C57BL/6 aortic segments. In conclusion, hAPP23 +/- mice exhibited high serum corticosterone levels, elevated systolic blood pressure, and increased arterial stiffness in vivo. However, ex vivo aortic stiffness of hAPP23 +/- aortic segments was not changed and vascular reactivity to α 1 -adrenoceptor stimulation was attenuated. These findings highlight the need for more frequent assessment of circulating stress hormone levels and PWV measurements in daily clinical practice for people at risk of AD. NEW & NOTEWORTHY We showed that male amyloid precursor protein (APP) transgenic mice have higher circulating stress hormone levels. As a result, higher systolic blood pressure and pulse-wave velocity were measured in vivo in addition to a smaller α-adrenergic receptor-dependent contraction upon ex vivo stimulation with phenylephrine. Our findings highlight the need for more frequent assessment of circulating stress hormone levels and PWV measurements in daily clinical practice for people at risk of Alzheimer's disease.

Streptolysin O (SLO) is produced by common hemolytic streptococci that cause a wide range of diseases from pharyngitis to life-threatening necrotizing fasciitis and toxic shock syndrome. Although the importance of SLO in invasive hemolytic streptococcus infection has been well demonstrated, the role of circulating SLO in noninvasive infection remains unclear. The aim of this study was to characterize the pharmacological effect of SLO on vascular functions, focusing on cellular signaling pathways. In control Wistar rats, SLO treatment (1-1000 ng/ml) impaired acetylcholine-induced endothelial-dependent relaxation in the aorta and second-order mesenteric artery in a dose-dependent manner without any effects on sodium nitroprusside-induced endothelium-independent relaxation or agonist-induced contractions. SLO also increased phosphorylation of the endothelial NO synthase (eNOS) inhibitory site at Thr495 in the aorta. Pharmacological analysis indicated that either endothelial dysfunction or eNOS phosphorylation was mediated by protein kinase C β (PKC β ), but not by the p38 mitogen-activated protein kinase pathway. Consistent with this, SLO increased phosphorylation levels of protein kinase C substrates in the aorta. In vivo study of control Wistar rats indicated that intravenous administration of SLO did not change basal blood pressure but significantly counteracted the acetylcholine-induced decrease in blood pressure. Interestingly, plasma anti-SLO IgG levels were significantly higher in 10- to 15-week-old spontaneously hypertensive rats compared with age-matched control rats ( P < 0.05). These findings demonstrated that SLO causes vascular endothelial dysfunction, which is mediated by PKC β -induced phosphorylation of the eNOS inhibitory site. SIGNIFICANCE STATEMENT: This study showed for the first time that in vitro exposure of vascular tissues to SLO impairs endothelial function, an effect that is mediated by protein kinase C β- induced phosphorylation of the endothelial NO synthase inhibitory site. Intravenous administration of SLO in control and hypertensive rats blunted the acetylcholine-induced decrease in blood pressure, providing evidence for a possible role of SLO in dysregulation of blood pressure., (Copyright © 2021 by The American Society for Pharmacology and Experimental Therapeutics.)

Recently, the addition of copper nanoparticles (NPs) in a daily diet (6.5 mg/kg) was studied in different animal models as a possible alternative to ionic forms. Male Wistar-Kyoto rats (24-week-old, n = 11) were fed with copper, either in the form of carbonate salt (Cu 6.5 ) or metal-based copper NPs (NP 6.5 ), for 8 weeks. The third group was fed with a half dose of each (NP 3.25 + Cu 3.25 ). The thoracic aorta and blood plasma was studied. Supplementation with NP 6.5 decreased the Cu (×0.7), Cu/Zn-ratio (×0.6) and catalase (CAT, ×0.7), and increased Zn (×1.2) and superoxide dismutase (SOD, ×1.4). Meanwhile, NP 3.25 + Cu 3.25 decreased the Cu/Zn-ratio (×0.7), and CAT (×0.7), and increased the daily feed intake (×1.06). Preincubation with either the selective cyclooxygenase (COX)-2 inhibitor, or the non-selective COX-1/2 inhibitor attenuated vasodilation of rat thoracic aorta in the NP 6.5 group exclusively. However, an increased vasodilator response was observed in the NP 6.5 and NP 3.25 + Cu 3.25 group of rats after preincubation with an inhibitor of 20-hydroxyeicosatetraenoic acid (20-HETE) formation, and the thromboxane receptor (TP) antagonist. Significant differences were observed between the NP 6.5 and NP 3.25 + Cu 3.25 groups of rats in: dietary intake, acetylcholine-induced vasodilation, and response to COX-inhibitors. Copper NPs in a standard daily dose had more significant effects on the mechanism(s) responsible for the utilization of reactive oxygen species in the blood plasma with the participation of prostanoids derived from COX-2 in the vascular relaxation. Dietary copper NPs in both doses modified vasodilation through the vasoconstrictor 20-HETE and the TP receptors.

Hypertension is one of the most common complications of chronic kidney disease (CKD). Some research has indicated that changes in large artery function especially caused by thromboxane A2 (TXA2) may be a novel factor acting to induce hypertension in CKD. We studied the 5/6 nephrectomy rat model and measured serum levels of creatinine (Cr), calcium (Ca), phosphorus (P), TXA2-stable metabolites (thromboxane B2, TXB2), and caudal artery pressure after nephrectomy. The tension variations in thoracic aortas were measured after stimulating by vasoconstrictor/vasodilator using the cumulative concentration administration method and then tested the expression of TXA2 receptors in the thoracic aortas through western blots. The CKD rats developed uremia, electrolyte imbalances，and hypertension. They also exhibited a significant increase in TXB2 concentration. The aortic rings of CKD rats showed an increased contraction response to U46619 (a TXA2 analogue) and the expression of TXA2 receptors also enhanced. In the meanwhile, the diastolic function decreased in the CKD group. Our results demonstrate that the impairment of artery contractile function caused by the increase of TXA2 receptors on the wall of aortic rings may be involved in hypertension in CKD rats., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Stephania abyssinica is a medicinal plant used in Cameroon alternative medicine to treat arterial hypertension (AHT). Previous in vitro studies demonstrated the endothelium nitric oxide-independent vasorelaxant property of the aqueous extract from Stephania abyssinica (AESA). But its effect on AHT is unknown. The present study was undertaken to explore other vasorelaxant mechanisms and to determine the antihypertensive effects of AESA in male Wistar rats. Phytochemical analysis of AESA was carried out using the liquid chromatography-mass spectrometry (LC-MS) method. The vasorelaxant effects of AESA (1-1000  μ g/mL) were studied on rat isolated thoracic aorta rings, in the absence or presence of indomethacin (10  μ M) or methylene blue (10  μ M). The inhibitory effect of AESA on phenylephrine (PE, 10  μ M) or KCl- (60 mM) induced contraction as well as the intracellular calcium release was also evaluated. The in vivo antihypertensive activity of AESA (43, 86, or 172 mg/kg/day) or captopril (20 mg/kg/day) administered orally was assessed in L-NAME- (40 mg/kg/day) treated rats. Blood pressure and heart rate (HR) were measured at the end of each week while serum or urinary nitric oxide (NO), creatinine, and glomerular filtration rate (GFR) were determined at the end of the 6 weeks of treatment, as well as histological analysis of the heart and the kidney. The LC-MS profiling of AESA identified 9 compounds including 7 alkaloids. AESA produced a concentration-dependent relaxation on contraction induced either by PE and KCl, which was significantly reduced in endothelium-denuded vessels, as well as in vessels pretreated with indomethacin and methylene blue. Moreover, AESA inhibited the intracellular Ca 2+ release-induced contraction. In vivo, AESA reduced the AHT, heart rate (HR), and ventricular hypertrophy and increased serum NO, urine creatinine, and GFR. AESA also ameliorated heart and kidney lesions as compared to the L-NAME group. These findings supported the use of AESA as a potential antihypertensive drug., Competing Interests: The authors declare that there is no conflict of interest., (Copyright © 2021 Chamberlin Fodem et al.)

Insulin resistance is a feature of pregnancy and is associated with increased levels of angiotensin II (Ang II) and insulin. Therefore, pregnancy may change insulin-induced vasodilation through changes in Ang II receptors. Insulin-induced vasorelaxation was evaluated in phenylephrine-precontracted aortic rings of pregnant and non-pregnant rats, using a conventional isolated organ preparation. Experiments were performed in thoracic or abdominal aorta rings with or without endothelium in the presence and absence of N G -nitro-L-arginine methyl ester (L-NAME) (10 -5 M), losartan (10 -7 M), or PD123319 (10 -7 M). AT1 and AT2 receptor expressions were detected by immunohistochemistry. Insulin-induced vasodilation was endothelium- and nitric oxide-dependent and decreased in the thoracic aorta but increased in the abdominal segment of pregnant rats. The insulin's vasorelaxant effect was increased by losartan mainly on the thoracic aorta. PD123319 decreased insulin-induced vasorelaxation mainly in the pregnant rat abdominal aorta. AT1 receptor expression was decreased while AT2 receptor expression was increased by pregnancy. In conclusion, pregnancy changes insulin-induced vasorelaxation. Moreover, insulin vasodilation is tonically inhibited by AT1 receptors, while AT2 receptors appear to have an insulin-sensitizing effect. The role of pregnancy and Ang II receptors differ depending on the aorta segment. These results shed light on the role of pregnancy and Ang II receptors on the regulation of insulin-mediated vasodilation.

Tobacco smoke is an established risk factor for thoracic aortic aneurysms and dissections (TAAD). However, little is known about its underlying mechanisms due to the lack of validated animal models. The present study developed a mouse model that may be utilized to investigate exacerbation of TAAD formation by mimetics of tobacco smoke. TAADs were created via inducible deletion of smooth muscle cell-specific Tgfbr2 receptors. Using this model, the first set of experiments evaluated the efficacy of nicotine salt (34.0 mg/kg/day), nicotine free base (NFB, 5.0 mg 90-day pellets), and cigarette smoke extract (0.1 ml/mouse/day). Compared with their respective control groups, only NFB pellets promoted TAAD dilation (23 ± 3% vs. 12 ± 2%, P = 0.014), and this efficacy was achieved at a cost of >50% acute mortality. Infusion of NFB with osmotic minipumps at extremely high, but nonlethal, doses (15.0 or 45.0 mg/kg/day) failed to accelerate TAAD dilation. Interestingly, costimulation with β -aminopropionitrile (BAPN) promoted TAAD dilation and aortic rupture at dosages of 3.0 and 45.0 mg/kg/day, respectively, indicating that BAPN sensitizes the response of TAADs to NFB. In subsequent analyses, the detrimental effects of NFB were associated with clustering of macrophages, neutrophils, and T-cells in areas with structural destruction, enhanced matrix metalloproteinase- (MMP-) 2 production, and pathological angiogenesis with attenuated fibrosis in the adventitia. In conclusion, modeling nicotine exacerbation of TAAD formation requires optimization of chemical form, route of delivery, and dosage of the drug as well as the pathologic complexity of TAADs. Under the optimized conditions of the present study, chronic inflammation and adventitial mal-remodeling serve as critical pathways through which NFB exacerbates TAAD formation., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Changzoon Chun et al.)

Background: Vascular dysfunction is a checkpoint to the development of hypertension. Heparan sulfate proteoglycans (HSPG) participate in nitric oxide (NO) and calcium signaling, key regulators of vascular function. The relationship between HSPG-mediated NO and calcium signaling and vascular dysfunction has not been explored. Likewise, the role of HSPG on the control of systemic blood arterial pressure is unknown. Herein, we sought to determine if the HSPG syndecan 1 and glypican 1 control systemic blood pressure and the progression of hypertension., Purpose: To determine the mechanisms whereby glypican 1 and syndecan 1 regulate vascular tone and contribute to the development of noradrenergic hypertension., Experimental Approach and Key Results: By assessing systemic arterial blood pressure we observed that syndecan 1 (Sdc1 -/- ) and glypican 1 (Gpc1 -/- ) knockout mice show a similar phenotype of decreased systolic blood pressure that is presented in a striking manner in the Gpc1 -/- strain. Gpc1 -/- mice are also uniquely protected from a norepinephrine hypertensive challenge failing to become hypertensive. This phenotype was associated with impaired calcium-dependent vasoconstriction and altered expression of calcium-sensitive proteins including SERCA and calmodulin. In addition, Gpc1 -/- distinctively showed decreased IP 3 R activity and increased calcium storage in the endoplasmic reticulum., Conclusions and Implications: Glypican 1 is a trigger for the development of noradrenergic hypertension that acts via IP 3 R- and calcium-dependent signaling pathways. Glypican 1 may be a potential target for the development of new therapies for resistant hypertension or conditions where norepinephrine levels are increased., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Acrolein, an electrophilic α,β-unsaturated aldehyde, is present in foods and beverages, and is a product of incomplete combustion, and thus, reaches high ppm levels in tobacco smoke and structural fires. Exposure to acrolein is linked with cardiopulmonary toxicity and cardiovascular disease risk. The hypothesis of this study is the direct effects of acrolein in isolated murine blood vessels (aorta and superior mesenteric artery, SMA) are transient receptor potential ankyrin-1 (TRPA1) dependent. Using isometric myography, isolated aorta and SMA were exposed to increasing levels of acrolein. Acrolein inhibited phenylephrine (PE)-induced contractions (approximately 90%) in aorta and SMA of male and female mice in a concentration-dependent (0.01-100 μM) manner. The major metabolite of acrolein, 3-hydroxypropylmercapturic acid (3HPMA), also relaxed PE-precontracted SMA. As the SMA was 20× more sensitive to acrolein than aorta (SMA EC 50 0.8 ± 0.2 μM; aorta EC 50  > 29.4 ± 4.4 μM), the mechanisms of acrolein-induced relaxation were studied in SMA. The potency of acrolein-induced relaxation was inhibited significantly by: 1) mechanically-impaired endothelium; 2) Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME); 3) guanylyl cyclase (GC) inhibitor (ODQ); and, 4) a TRPA1 antagonist (A967079). TRPA1 positive immunofluorescence was present in the endothelium. Compared with other known TRPA1 agonists, including allyl isothiocyanate (AITC), cinnamaldehyde, crotonaldehyde, and formaldehyde, acrolein stimulated a more potent TRPA1-dependent relaxation. Acrolein, at high concentration [100 μM], induced tension oscillations (spasms) independent of TRPA1 in precontracted SMA but not in aorta. In conclusion, acrolein is vasorelaxant at low levels (physiological) yet vasotoxic at high levels (toxicological)., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: Despite considerable research, the goal of finding nonsurgical remedies against thoracic aortic aneurysm and acute aortic dissection remains elusive. We sought to identify a novel aortic PK (protein kinase) that can be pharmacologically targeted to mitigate aneurysmal disease in a well-established mouse model of early-onset progressively severe Marfan syndrome (MFS)., Approach and Results: Computational analyses of transcriptomic data derived from the ascending aorta of MFS mice predicted a probable association between thoracic aortic aneurysm and acute aortic dissection development and the multifunctional, stress-activated HIPK2 (homeodomain-interacting protein kinase 2). Consistent with this prediction, Hipk2 gene inactivation significantly extended the survival of MFS mice by slowing aneurysm growth and delaying transmural rupture. HIPK2 also ranked among the top predicted PKs in computational analyses of DEGs (differentially expressed genes) in the dilated aorta of 3 MFS patients, which strengthened the clinical relevance of the experimental finding. Additional in silico analyses of the human and mouse data sets identified the TGF (transforming growth factor)-β/Smad3 signaling pathway as a potential target of HIPK2 in the MFS aorta. Chronic treatment of MFS mice with an allosteric inhibitor of HIPK2-mediated stimulation of Smad3 signaling validated this prediction by mitigating thoracic aortic aneurysm and acute aortic dissection pathology and partially improving aortic material stiffness., Conclusions: HIPK2 is a previously unrecognized determinant of aneurysmal disease and an attractive new target for antithoracic aortic aneurysm and acute aortic dissection multidrug therapy.

The physiological function of amyloid precursor protein (APP) in the control of endothelial function during aging is unclear. Aortas of young (4-6 months old) and aged (23-26 months old) wild-type (WT) and endothelium-specific APP-deficient (eAPP -/- ) mice were used to study aging-induced changes in vascular phenotype. Unexpectedly, aging significantly increased protein expression of APP in aortas of WT mice but not in aortas of eAPP -/- mice thereby demonstrating selective upregulation APP expression in vascular endothelium of aged aortas. Most notably, endothelial dysfunction (impairment of endothelium-dependent relaxations) induced by aging was significantly exacerbated in aged eAPP -/- mice aortas as compared to age-matched WT mice. Consistent with this observations, endothelial nitric oxide synthase (eNOS) protein expression was significantly decreased in aged eAPP -/- mice as compared to age matched WT mice. In addition, protein expression of cyclooxygenase 2 and release of prostaglandins were significantly increased in both aged WT and eAPP -/- mice. Notably, treatment with cyclooxygenase inhibitor, indomethacin, normalized endothelium-dependent relaxations in aged WT mice, but not in aged eAPP -/- mice. In aggregate, our findings support the concept that aging-induced upregulation of APP in vascular endothelium is an adaptive response designed to protect and preserve expression and function of eNOS .