Trimethylamine N-Oxide Promotes Autoimmunity and a Loss of Vascular Function in Toll-like Receptor 7-Driven Lupus Mice

Plasma levels of trimethylamine N-oxide (TMAO) are elevated in lupus patients. We analyzed the implication of TMAO in autoimmunity and vascular dysfunction of the murine model of systemic lupus erythematosus (SLE) induced by the activation of the Toll-like receptor (TLR)7 with imiquimod (IMQ). Female BALB/c mice were randomly divided into four groups: untreated control mice, control mice treated with the trimethylamine lyase inhibitor 3,3-dimethyl-1-butanol (DMB), IMQ mice, and IMQ mice treated with DMB. The DMB-treated groups were administered the substance in their drinking water for 8 weeks. Treatment with DMB reduced plasma levels of TMAO in mice with IMQ-induced lupus. DMB prevents the development of hypertension, reduces disease progression (plasma levels of anti-dsDNA autoantibodies, splenomegaly, and proteinuria), reduces polarization of T lymphocytes towards Th17/Th1 in secondary lymph organs, and improves endothelial function in mice with IMQ-induced lupus. The deleterious vascular effects caused by TMAO appear to be associated with an increase in vascular oxidative stress generated by increased NADPH oxidase activity, derived in part from the vascular infiltration of Th17/Th1 lymphocytes, and reduced nrf2-driven antioxidant defense. In conclusion, our findings identified the bacterial-derived TMAO as a regulator of immune system, allowing for the development of autoimmunity and endothelial dysfunction in SLE mice.

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Abstract P083: Fetuin-a Induces Vascular Dysfunction Through Toll-like Receptor 4 And Nox1/4 Activation

Hypertension ◽

10.1161/hyp.76.suppl_1.p083 ◽

2020 ◽

Vol 76 (Suppl_1) ◽

Author(s):

Karla B Neves ◽

Rheure A Lopes ◽

Anastasiya Strembitska ◽

Ross Hepburn ◽

Wendy Beattie ◽

...

Keyword(s):

Vascular Function ◽

Molecular Mechanisms ◽

Vascular Dysfunction ◽

Convincing Evidence ◽

Ros Production ◽

Toll Like Receptor ◽

Vascular Effects ◽

Toll Like Receptor 4 ◽

Fetuin A ◽

Wky Rats

Although studies demonstrate an important role for fetuin-A (FetA) in the inhibition of vascular calcification, convincing evidence suggests that fetuin-A is also involved in insulin resistance, inflammation and cardiovascular damage. The present study seeks to unravel FetA vascular effects and associated molecular mechanisms, focusing on oxidative stress and toll-like receptor 4 (TLR4). Vascular function studies were performed in mesenteric resistance arteries from WKY rats, wild-type, Nox1 KO, Nox4 KO and Ang II-dependent hypertensive mice (LinA3) and rat aortic endothelial cells (RAEC). ROS production (chemiluminescence, Amplex Red, ELISA) and pro-inflammatory markers expression (RT-PCR) were measured in VSMCs from WKY rats and RAEC. FetA impaired endothelium-dependent (LogEC50 7.320±0.08 M vs control 8.025±0.06) and endothelium-independent vasorelaxation (LogEC50 6.48±0.19 M vs control 7.38±0.12), p<0.05; effects blocked by tempol (superoxide dismutase mimetic), Nox1 inhibitor, ML171, and TLR4 inhibitor, CLI095. We did not observe any changes in contraction. FetA increased ROS production (62%) and peroxynitrite levels (158%) in VSMCs; while in RAEC, FetA increased ROS production (105%) followed by a decrease in H2O2 (62%) levels (p<0.05 vs control). FetA-induced effects on ROS were inhibited by ML171 and GKT137831 (Nox1/Nox4 inhibitor), as well as CLI095. Vascular dysfunction in arteries from Nox1 and Nox4 KO mice was unaffected by FetA. Activation of the FetA/TLR4/Nox axis led to an increase in IL-1β (190%), Il-6 (124%) and RANTES mRNA expression(116%) in RAEC, p<0.05 vs control. FetA enhanced vascular dysfunctionin LinA3 mice. Together, these results suggest that FetA through TLR4/Nox1 and 4-derived ROS leads to vascular dysfunction and inflammation, which may play an important role in the development of vascular injury during hypertension.

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Unacylated Ghrelin Improves Vascular Dysfunction and Attenuates Atherosclerosis during High-Fat Diet Consumption in Rodents

International Journal of Molecular Sciences ◽

10.3390/ijms20030499 ◽

2019 ◽

Vol 20 (3) ◽

pp. 499 ◽

Cited By ~ 6

Author(s):

Michela Zanetti ◽

Gianluca Gortan Cappellari ◽

Andrea Graziani ◽

Rocco Barazzoni

Keyword(s):

Oxidative Stress ◽

Lipid Accumulation ◽

High Fat Diet ◽

Vascular Function ◽

Vascular Dysfunction ◽

High Fat ◽

Enos Expression ◽

Unacylated Ghrelin ◽

Vascular Oxidative Stress ◽

Expression And Activity

Unacylated ghrelin (UnGhr) exerts several beneficial actions on vascular function. The aim of this study was to assess the effects of UnGhr on high-fat induced endothelial dysfunction and its underlying mechanisms. Thoracic aortas from transgenic mice, which were overexpressing UnGhr and being control fed either a standard control diet (CD) or a high-fat diet (HFD) for 16 weeks, were harvested and used for the assessment of vascular reactivity, endothelial nitric oxide synthase (eNOS) expression and activity, thiobarbituric acid reactive substances (TBARS) and glutathione levels, and aortic lipid accumulation by Oil Red O staining. Relaxations due to acetylcholine and to DEA-NONOate were reduced (p < 0.05) in the HFD control aortas compared to vessels from the CD animals. Overexpression of UnGhr prevented HFD-induced vascular dysfunction, while eNOS expression and activity were similar in all vessels. HFD-induced vascular oxidative stress was demonstrated by increased (p < 0.05) aortic TBARS and glutathione in wild type (Wt) mice; however, this was not seen in UnGhr mice. Moreover, increased (p < 0.05) HFD-induced lipid accumulation in vessels from Wt mice was prevented by UnGhr overexpression. In conclusion, chronic UnGhr overexpression results in improved vascular function and reduced plaque formation through decreased vascular oxidative stress, without affecting the eNOS pathway. This research may provide new insight into the mechanisms underlying the beneficial effects of UnGhr on the vascular dysfunction associated with obesity and the metabolic syndrome.

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Curcumin Therapy to Treat Vascular Dysfunction in Children and Young Adults with ADPKD

Clinical Journal of the American Society of Nephrology ◽

10.2215/cjn.08950621 ◽

2021 ◽

pp. CJN.08950621

Author(s):

Kristen Nowak ◽

Heather Farmer-Bailey ◽

Wei Wang ◽

Zhiying You ◽

Cortney Steele ◽

...

Keyword(s):

Oxidative Stress ◽

Young Adults ◽

Vascular Function ◽

Vascular Dysfunction ◽

Clinical Manifestations ◽

Kidney Volume ◽

Total Kidney Volume ◽

Double Blind ◽

Kidney Growth ◽

Vascular Oxidative Stress

Background and Objectives: Clinical manifestations of autosomal dominant polycystic kidney disease (ADPKD), including evidence of vascular dysfunction, can begin in childhood. Curcumin is a polyphenol found in turmeric that reduces vascular dysfunction in rodent models and humans without ADPKD. It also slows kidney cystic progression in a murine model of ADPKD. We hypothesized that oral curcumin therapy would reduce vascular endothelial dysfunction and arterial stiffness in children/young adults with ADPKD. Design, Setting, Participants, and Measurements: In a randomized, placebo-controlled, double-blind trial, 68 children/ young adults 6-25 years of age with ADPKD and an estimated glomerular filtration rate >80 mL/min/1.73 m2 were randomized to either curcumin supplementation (25 mg/kg body weight/day) or placebo, administered in powder form for 12 months. The co-primary outcomes were brachial artery flow-mediated dilation [FMDBA] and aortic pulse-wave velocity [aPWV]. We also assessed change in circulating/urine biomarkers of oxidative stress/inflammation and kidney growth (height-adjusted total kidney volume]) by magnetic resonance imaging. In a sub-group of participants ≥18 years, vascular oxidative stress was measured as the change in FMDBA following an acute infusion of ascorbic acid. Results: Enrolled participants were 18±5 [mean±s.d.] years; 54% female; baseline FMDBA was 9.3±4.1 % change, and baseline aPWV was 512±94 cm/sec. Fifty-seven participants completed the trial. Neither co-primary endpoint changed with curcumin (estimated change [95% confidence interval] for FMDBA (% change): curcumin: 1.14 [-0.84, 3.13]; placebo: 0.33 [-1.34, 2.00]; estimated difference for change: 0.81 [-1.21, 2.84], p=0.48; aPWV (cm/sec: curcumin: 0.6 [-25.7, 26.9]; placebo: 6.5 [-20.4, 33.5]; estimated difference for change: -5.9 [-35.8, 24.0], p=0.67) (intent to treat). There was no curcumin-specific reduction in vascular oxidative stress, nor changes in mechanistic biomarkers. Height-adjusted total kidney volume also did not change as compared to placebo. Conclusions: Curcumin supplementation does not improve vascular function or slow kidney growth in children/young adults with ADPKD.

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Increased superoxide production and altered nitric oxide-mediated relaxation in the aorta of young but not old male relaxin-deficient mice

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00786.2014 ◽

2015 ◽

Vol 309 (2) ◽

pp. H285-H296 ◽

Cited By ~ 26

Author(s):

Hooi H. Ng ◽

Maria Jelinic ◽

Laura J. Parry ◽

Chen-Huei Leo

Keyword(s):

Nitric Oxide ◽

Vascular Function ◽

Vascular Dysfunction ◽

Superoxide Production ◽

Resistance Arteries ◽

Vascular Effects ◽

Small Resistance ◽

Ros Scavenger ◽

Relaxation Responses ◽

Endothelial Nitric Oxide

The vascular effects of exogenous relaxin (Rln) treatment are well established and include decreased myogenic reactivity and enhanced relaxation responses to vasodilators in small resistance arteries. These vascular responses are reduced in older animals, suggesting that Rln is less effective in mediating arterial function with aging. The present study investigated the role of endogenous Rln in the aorta and the possibility that vascular dysfunction occurs more rapidly with aging in Rln-deficient ( Rln−/−) mice. We compared vascular function and underlying vasodilatory pathways in the aorta of male wild-type ( Rln+/+) and Rln−/− mice at 4 and 16 mo of age using wire myography. Superoxide production, but not nitrotyrosine or NADPH oxidase expression, was significantly increased in the aorta of young Rln−/− mice, whereas endothelial nitric oxide (NO) synthase and basal NO availability were both significantly decreased compared with Rln+/+ mice. In the presence of the cyclooxygenase inhibitor indomethacin, sensitivity to ACh was significantly decreased in young Rln−/− mice, demonstrating altered NO-mediated relaxation that was normalized in the presence of a membrane-permeable SOD or ROS scavenger. These vascular phenotypes were not exacerbated in old Rln−/− mice and, in most cases, did not differ significantly from old Rln+/+ mice. Despite the vascular phenotypes in Rln−/− mice, endothelium-dependent and -independent vasodilation were not adversely affected. Our data show a role for endogenous Rln in reducing superoxide production and maintaining NO availability in the aorta but also demonstrate that Rln deficiency does not compromise vascular function in this artery or exacerbate endothelial dysfunction associated with aging.

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Gut Microbiota Has a Crucial Role in the Development of Hypertension and Vascular Dysfunction in Toll-like Receptor 7-Driven Lupus Autoimmunity

Antioxidants ◽

10.3390/antiox10091426 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1426

Author(s):

Néstor de la Visitación ◽

Iñaki Robles-Vera ◽

Javier Moleón ◽

Cristina González-Correa ◽

Nazaret Aguilera-Sánchez ◽

...

Keyword(s):

Blood Pressure ◽

Gut Microbiota ◽

Lupus Erythematosus ◽

Vascular Dysfunction ◽

Vascular Inflammation ◽

Vascular Complications ◽

Kidney Injury ◽

Interleukin 17 ◽

Toll Like Receptor ◽

Th 17

Our group has investigated the involvement of gut microbiota in hypertension in a murine model of systemic lupus erythematosus induced by Toll-like receptor (TLR)-7 activation. Female BALB/c mice were randomly assigned to four experimental groups: an untreated control (CTR), a group treated with the TLR7 agonist imiquimod (IMQ), IMQ-treated with vancomycin, and IMQ-treated with a cocktail of broad-spectrum antibiotics. We carried out faecal microbiota transplant (FMT) from donor CTR or IMQ mice to recipient IMQ or CTR animals, respectively. Vancomycin inhibited the increase in blood pressure; improved kidney injury, endothelial function, and oxidative stress; and reduced T helper (Th)17 infiltration in aortas from IMQ-treated mice. The rise in blood pressure and vascular complications present in IMQ mice were also observed in the CTR mice recipients of IMQ microbiota. Reduced relative populations of Sutterella and Anaerovibrio were associated with high blood pressure in our animals, which were increased after stool transplantation of healthy microbiota to IMQ mice. The reduced endothelium-dependent vasodilator responses to acetylcholine induced by IMQ microbiota were normalized after interleukin-17 neutralization. In conclusion, gut microbiota plays a role in the TLR7-driven increase in Th17 cell, endothelial dysfunction, vascular inflammation, and hypertension. The vascular changes induced by IMQ microbiota were initiated by Th17 infiltrating the vasculature.

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Abstract 099: Fetuin-A and Toll-like Receptor 4 Regulate Vascular Function: Role of Nox1

Hypertension ◽

10.1161/hyp.66.suppl_1.099 ◽

2015 ◽

Vol 66 (suppl_1) ◽

Author(s):

Augusto C Montezano ◽

Karla B Neves ◽

Rheure A Lopes ◽

Susan Leckerman ◽

Anastasiya Strembitska ◽

...

Keyword(s):

Endothelial Dysfunction ◽

Protein Oxidation ◽

Vascular Function ◽

Vascular Dysfunction ◽

Rho Kinase ◽

Mesenteric Arteries ◽

Ros Production ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

Fetuin A

Fetuin-A (FetA) regulates calcium and phosphate homeostasis. It is also an agonist to toll-like receptor 4 (TLR4) and is related to insulin resistance and inflammation. FetA has also been associated with endothelial dysfunction, which is regulated by oxidative stress. Mechanisms whereby FetA influences vascular function are unknown. We hypothesized that FetA through TLR4 and ROS production induces vascular dysfunction. Mesenteric arteries and vascular cells from WKY rats were studied. Vascular function was analysed by wire myography in the presence or absence of FetA (50 ng/mL) and/or CLI095 (CLI - 10-6M - TLR4 inhibitor). Levels of reactive oxygen species (ROS) were measured by chemiluminescence, Amplex Red (H2O2) and ELISA (nitrotyrosine) Protein oxidation and levels were measured by immunoblotting. WKY vessels exposed to FetA were less sensitive to acetylcholine (Ach)-induced and sodium nitroprusside (SNP)-induced relaxation, while sensitivity to phenylephrine was increased by FetA; an effect blocked by N-acetylcysteine (antioxidant) and ML171 (Nox1 inhibitor). Inhibition of TLR4 blocked FetA effects on endothelial-dependent relaxation and contraction, but not on endothelial-independent relaxation. FetA increased ROS production (131±49.2%), but decreased H2O2 intracellular levels (63±14%) in endothelial cells (EC) (vs. veh, p<0.05); an effect blocked by CLI095. ROS production (66±12.2%), as well as, H2O2 (45±8%) and ONOO- (105±31.6%) levels, were increased by FetA in VSMCs (vs. veh, p<0.05). Protein oxidation was increased by FetA in VSMCs (103±26% vs. veh, p<0.05). In EC, eNOS inactivation (136±38%) and JNK activation (84±5%) were increased by FetA (vs. veh, p<0.05). In VSMCs, Rho kinase activity was increased (200±25% vs. veh, p<0.05) at 30 min; while myosin light chain (MLC) activation was only increased (25±3.56% vs. veh, p<0.05) at 15 min. In summary, FetA influences vascular function through Nox1-ROS dependent mechanisms. FetA-induced endothelial dysfunction and contractile responses involve TLR4. Our findings identify a novel system whereby FetA differentially influences vascular function through Nox1-ROS and TLR4. Vascular responses to FetA may depend on the specific pathway activated.

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Abstract P228: Protective Role of TRPM7-kinase Against Vascular Dysfunction and Fibrosis Induced by Aldosterone and Salt

Hypertension ◽

10.1161/hyp.68.suppl_1.p228 ◽

2016 ◽

Vol 68 (suppl_1) ◽

Author(s):

Francisco J Rios ◽

Katie Y Hood ◽

Adam Harvey ◽

Karla B Neves ◽

Ryszard Nosalski ◽

...

Keyword(s):

Protein Expression ◽

Vascular Function ◽

Cardiac Fibrosis ◽

Cardiac Tissue ◽

Vascular Dysfunction ◽

Mesenteric Arteries ◽

Vascular Effects ◽

Cross Sectional ◽

Induced Hypertension

TRPM7 is a cationic ion channel and with a serine/threonine kinase important for cellular Mg 2+ homeostasis. We recently showed that TRPM7-kinase plays a role in aldosterone-mediated vascular effects and inflammation. Here we explored the role of TRPM7-kinase in cardiac fibrosis and vascular function in aldosterone-induced hypertension in mice. Wild-type (WT) or heterozygote TRPM7-kinase domain (TRPM7+/-) were treated with infused aldosterone (600 μg/Kg/day) and NaCl 1% in drinking water (aldo/salt) for 4 weeks. Blood pressure (BP) was evaluated by tail-cuff. Vessel function was investigated in mesenteric arteries by wire and pressure myography. Protein expression was assessed in cardiac tissue by western-blot and histology. Aldo/salt increased BP in TRPM7+/- and WT to similar levels (137mmHg vs control 118mmHg). Mesenteric arteries from untreated TRPM7+/- mice were more sensitive to relaxation induced by acetylcholine (LogEC50: 7.6±0.1 vs 7.1±0.2, TRPM7+/- and WT, respectively), effects that were reduced by Aldo/salt treatment (LogEC50: 7.2±0.1). Phenylephrine-contraction and sodium nitroprusside-relaxation curves were similar among groups. Pressure myography showed that in WT, aldo/salt increase the diameter (26%) and cross-sectional area (40%), resulting in hypertrophic outward remodelling, whereas in TRPM7+/-, the treatment decreased the diameter (16%) and increase the wall/lumen ration (82%), resulting in eutrophic inward remodelling. Hearts from TRPM7+/- presented decreased expression of annexin-1, which is a target protein of TRPM7-kinase, that was further decreased by aldo-salt. Hearts from untreated TRPM7+/- mice had increased fibrotic markers: plasma galectin-3 (2.5ng/mL) vs WT (1.4ng/mL) and protein expression for fibronectin (2.4-fold) and TGFβ (2-fold), and the aging marker p-P66Sch (47%) which were similar to WT-aldo/salt. Aldo/salt induced higher collagen expression in TRPM7+/- than in WT animals (15%), as observed by picrosirius red staining. Our findings provide some insights into aldosterone signalling through TRPM7-kinase and suggest that this chanzyme may have protective actions, which when downregulated, promotes vascular remodelling and cardiac fibrosis in aldosterone-induced hypertension.

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Vascular dysfunction in young, mid-aged and aged mice with latent cytomegalovirus infections

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00461.2012 ◽

2013 ◽

Vol 304 (2) ◽

pp. H183-H194 ◽

Cited By ~ 8

Author(s):

R. B. Gombos ◽

J. C. Brown ◽

J. Teefy ◽

R. L. Gibeault ◽

K. L. Conn ◽

...

Keyword(s):

Vascular Function ◽

Vascular Dysfunction ◽

Vascular Diseases ◽

Mesenteric Arteries ◽

Nitric Oxide Donor ◽

Negative Effects ◽

Vascular Effects ◽

Vascular Responses ◽

Uterine Arteries ◽

Latently Infected

Human cytomegalovirus (HCMV) is associated with vascular diseases in both immunosuppressed and immunocompetent individuals. CMV infections cycle between active and latent phases throughout life. We and others have shown vascular dysfunction during active mouse CMV (mCMV) infections. Few studies have examined changes in physiology during latent CMV infections, particularly vascular responses or whether the negative effects of aging on vascular function and fertility will be exacerbated under these conditions. We measured vascular responses in intact mesenteric and uterine arteries dissected from young, mid-aged, and aged latently mCMV-infected (mCMV genomes are present but infectious virus is undetectable) and age-matched uninfected mice using a pressure myograph. We tested responses to the α1-adrenergic agonist phenylephrine, the nitric oxide donor sodium nitroprusside, and the endothelium-dependent vasodilator methacholine. In young latently mCMV-infected mice, vasoconstriction was increased and vasodilation was decreased in mesenteric arteries, whereas both vasoconstriction and vasodilation were increased in uterine arteries compared with those in age-matched uninfected mice. In reproductively active mid-aged latently infected mice, mesenteric arteries showed little change, whereas uterine arteries showed greatly increased vasoconstriction. These vascular effects may have contributed to the decreased reproductive success observed in mid-aged latently mCMV-infected compared with age-matched uninfected mice (16.7 vs. 46.7%, respectively). In aged latently infected mice, vasodilation is increased in mesenteric and uterine arteries likely to compensate for increased vasoconstriction to mediators other than phenylephrine. The novel results of this study show that even when active mCMV infections become undetectable, vascular dysfunction continues and differs with age and artery origin.

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