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1.
Int J Mol Sci ; 25(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38612675

RESUMO

There is a growing body of evidence that ER stress and the unfolded protein response (UPR) play a key role in numerous diseases. Impaired liver perfusion and ER stress often accompany each other in liver diseases. However, the exact impact of ER stress and UPR on the hepatic perfusion is not fully understood. The aim of this study was to disclose the effect of ER stress and UPR on the size of liver vessels and on the levels of Ca2+ and nitric oxide (NO), critical regulators of vascular tonus. This study was carried out in precisely cut liver tissue slices. Confocal microscopy was used to create 3D images of vessels. NO levels were determined either using either laser scan microscopy (LSM) in cells or by NO-analyser in medium. Ca2+ levels were analysed by LSM. We show that tunicamycin, an inducer of ER stress, acts similarly with vasodilator acetylcholine. Both exert a similar effect on the NO and Ca2+ levels; both induce significant vasodilation. Notably, this vasodilative effect persisted despite individual inhibition of UPR pathways-ATF-6, PERK, and IRE1-despite confirming the activation of UPR. Experiments with HUVEC cells showed that elevated NO levels did not result from endothelial NO synthase (eNOS) activation. Our study suggests that tunicamycin-mediated ER stress induces liver vessel vasodilation in an NO-dependent manner, which is mediated by intracellular nitrodilator-activatable NO store (NANOS) in smooth muscle cells rather than by eNOS.


Assuntos
Estresse do Retículo Endoplasmático , Vasodilatação , Tunicamicina/farmacologia , Resposta a Proteínas não Dobradas , Fígado
2.
Opt Lett ; 49(8): 2121-2124, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621091

RESUMO

The purpose of this study is to verify the effect of anisotropic property of retinal biomechanics on vasodilation measurement. A custom-built optical coherence tomography (OCT) was used for time-lapse imaging of flicker stimulation-evoked vessel lumen changes in mouse retinas. A comparative analysis revealed significantly larger (18.21%) lumen dilation in the axial direction compared to the lateral (10.77%) direction. The axial lumen dilation predominantly resulted from the top vessel wall movement toward the vitreous direction, whereas the bottom vessel wall remained stable. This observation indicates that the traditional vasodilation measurement in the lateral direction may result in an underestimated value.


Assuntos
Tomografia de Coerência Óptica , Vasodilatação , Animais , Camundongos , Vasodilatação/fisiologia , Tomografia de Coerência Óptica/métodos , Estimulação Luminosa/métodos , Retina/diagnóstico por imagem , Retina/fisiologia , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/fisiologia
3.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(3): 523-532, 2024 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-38597444

RESUMO

OBJECTIVE: To investigate the effect of asiaticoside on blood pressure and relaxation of thoracic aorta in rats and explore the underlying mechanism. METHODS: SD rats treated with 50 and 100 mg/kg asiaticoside by daily gavage for 2 weeks were monitored for systolic blood pressure changes, and histological changes of the thoracic aorta were evaluated using HE staining. In isolated rat endothelium-intact and endothelium-denuded thoracic aorta rings, the effects of asiaticoside on relaxation of the aortic rings were tested at baseline and following norepinephrine (NE)- and KCl-induced constriction. The vascular relaxation effect of asiaticoside was further observed in NE-stimulated endothelium-intact rat aortic rings pretreated with L-nitroarginine methyl ester, indomethacin, zinc protoporphyrin Ⅸ, tetraethyl ammonium chloride, glibenclamide, barium chloride, Iberiotoxin, 4-aminopyridine, or TASK-1-IN-1. The aortic rings were treated with KCl and NE followed by increasing concentrations of CaCl2 to investigate the effect of asiaticoside on vasoconstriction induced by external calcium influx and internal calcium release. RESULTS: Asiaticoside at 50 and 100 mg/kg significantly lowered systolic blood pressure in rats without affecting the thoracic aorta histomorphology. While not obviously affecting resting aortic rings with intact endothelium, asiaticoside at 100 mg/kg induced significant relaxation of the rings constricted by KCl and NE, but its effects differed between endothelium-intact and endothelium-denuded rings. In endothelium-intact aortic rings pretreated with indomethacin, ZnPP Ⅸ, barium chloride, glyburide, TASK-1-IN-1 and 4-aminopyridine, asiaticoside did not produce significant effect on NE-induced vasoconstriction, and tetraethylammonium, Iberiotoxin and L-nitroarginine methyl ester all inhibited the relaxation effect of asiaticoside. In KCland NE-treated rings, asiaticoside obviously inhibited CaCl2-induced vascular contraction. CONCLUSION: Asiaticoside induces thoracic aorta relaxation by mediating high-conductance calcium-activated potassium channel opening, promoting nitric oxide release from endothelial cells and regulating Ca2+ influx and outflow, thereby reducing systolic blood pressure in rats.


Assuntos
Aorta Torácica , Compostos de Bário , Cloretos , Triterpenos , Vasodilatação , Ratos , Animais , Pressão Sanguínea , Células Endoteliais , Cálcio , Cloreto de Cálcio/farmacologia , Nitroarginina/farmacologia , Ratos Sprague-Dawley , 4-Aminopiridina/farmacologia , Indometacina/farmacologia , Ésteres/farmacologia , Endotélio Vascular , Relação Dose-Resposta a Droga
4.
Physiol Rep ; 12(8): e16021, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38639714

RESUMO

We assessed the combined effect of superoxide and iNOS inhibition on microvascular function in non-Hispanic Black and non-Hispanic White participants (n = 15 per group). Participants were instrumented with four microdialysis fibers: (1) lactated Ringer's (control), (2) 10 µM tempol (superoxide inhibition), (3) 0.1 mM 1400 W (iNOS inhibition), (4) tempol + 1400 W. Cutaneous vasodilation was induced via local heating and NO-dependent vasodilation was quantified. At control sites, NO-dependent vasodilation was lower in non-Hispanic Black (45 ± 9% NO) relative to non-Hispanic White (79 ± 9% NO; p < 0.01; effect size, d = 3.78) participants. Tempol (62 ± 16% NO), 1400 W (78 ± 12% NO) and tempol +1400 W (80 ± 13% NO) increased NO-dependent vasodilation in non-Hispanic Black participants relative to control sites (all p < 0.01; d = 1.22, 3.05, 3.03, respectively). The effect of 1400 W (p = 0.04, d = 1.11) and tempol +1400 W (p = 0.03, d = 1.22) was greater than tempol in non-Hispanic Black participants. There was no difference between non-Hispanic Black and non-Hispanic White participants at 1400 W or tempol + 1400 W sites. These data suggest iNOS has a greater effect on NO-dependent vasodilation than superoxide in non-Hispanic Black participants.


Assuntos
Óxidos N-Cíclicos , Iminas , Óxido Nítrico , Marcadores de Spin , Vasodilatação , Humanos , Adulto Jovem , Óxido Nítrico/farmacologia , Vasodilatação/fisiologia , Superóxidos , Pele/irrigação sanguínea , Fluxo Sanguíneo Regional
5.
Artigo em Inglês | MEDLINE | ID: mdl-38524399

RESUMO

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in Overlap Syndrome (OS), the co-occurrence of Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease. Clustering of patients in subgroups with similar pre-clinical manifestations (ie, endothelial dysfunction) may identify relevant therapeutic phenotype categories for patients with OS who are at high risk of CVD. We therefore conducted a cross-sectional pilot study of endothelial function in 7 patients with OS (Forced Expiratory Volume in 1 second/Forced Vital Capacity < 0.7) on continuous positive airway pressure therapy (n = 7) to assess the relationship between FMD and physical activity. We found a strong association between FMD and step counts (rho = 0.77, p = 0.04); and FMD and moderate physical activity (rho = 0.9, p = 0.005). Further, larger studies are needed to confirm that FMD may identify patients with OS at high risk of CVD who benefit from increased physical activity.


Assuntos
Doenças Cardiovasculares , Doença Pulmonar Obstrutiva Crônica , Apneia Obstrutiva do Sono , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia , Doença Pulmonar Obstrutiva Crônica/complicações , Estudos Transversais , Vasodilatação , Artéria Braquial , Projetos Piloto , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/terapia , Apneia Obstrutiva do Sono/complicações , Síndrome , Acelerometria , Exercício Físico
6.
Free Radic Biol Med ; 217: 15-28, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38522485

RESUMO

OBJECTIVE: Mitochondrial ATP-sensitive K+ (mitoKATP) channels are involved in neuronal and cardiac protection from ischemia and oxidative stress. Penile erection is a neurovascular event mediated by relaxation of the erectile tissue via nitric oxide (NO) released from nerves and endothelium. In the present study, we investigated whether mitoKATP channels play a role in the control of penile vascular tone and mitochondrial dynamics, and the involvement of NO. METHODS: The effect of the selective mitoKATP activator BMS191095 was examined on vascular tone, on mitochondrial bioenergetics by real-time measurements with Agilent Seahorse and on ROS production by MitoSOX fluorescence in freshly isolated microarteries. RESULTS: BMS191095 and diazoxide relaxed penile arteries, BMS191095 being one order of magnitude more potent. BMS191095-induced relaxations were reduced by mechanical endothelium removal and by inhibitors of the nitric oxide synthase (NOS) and PI3K enzymes. The NO-dependent component of the relaxation to BMS191095 was impaired in penile arteries from insulin resistant obese rats. The blockers of mitoKATP channel 5-HD, sarcolemma KATP (sarcKATP) channel glibenclamide, and large conductance Ca2+-activated K+ (BKCa) channel iberiotoxin, inhibited relaxations to BMS191095 and to the NO donor SNAP. BMS191095 reduced the mitochondrial bioenergetic profile of penile arteries and attenuated mitochondrial ROS production. Blockade of endogenous NO impaired and exogenous NO mimicked, respectively, the inhibitory effects of BMS191095 on basal respiration and oxygen consumed for ATP synthesis. Exogenous NO exhibited dual inhibitory/stimulatory effects on mitochondrial respiration. CONCLUSIONS: These results demonstrate that selective activation of mitoKATP channels causes penile vasodilation, attenuates ROS production and inhibits mitochondrial respiration in part by releasing endothelial NO. These mechanisms couple blood flow and metabolism in penile arterial wall and suggest that activation of vascular mitoKATP channels may protect erectile tissue against ischemic injury.


Assuntos
Óxido Nítrico , Canais de Potássio , Vasodilatação , Masculino , Ratos , Animais , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Trifosfato de Adenosina , Respiração
7.
Science ; 383(6690): 1471-1478, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38547288

RESUMO

Consciousness is lost within seconds upon cessation of cerebral blood flow. The brain cannot store oxygen, and interruption of oxidative phosphorylation is fatal within minutes. Yet only rudimentary knowledge exists regarding cortical partial oxygen tension (Po2) dynamics under physiological conditions. Here we introduce Green enhanced Nano-lantern (GeNL), a genetically encoded bioluminescent oxygen indicator for Po2 imaging. In awake behaving mice, we uncover the existence of spontaneous, spatially defined "hypoxic pockets" and demonstrate their linkage to the abrogation of local capillary flow. Exercise reduced the burden of hypoxic pockets by 52% compared with rest. The study provides insight into cortical oxygen dynamics in awake behaving animals and concurrently establishes a tool to delineate the importance of oxygen tension in physiological processes and neurological diseases.


Assuntos
Córtex Cerebral , Circulação Cerebrovascular , Hipóxia Encefálica , Medições Luminescentes , Saturação de Oxigênio , Oxigênio , Animais , Camundongos , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Oxigênio/sangue , Oxigênio/metabolismo , Pressão Parcial , Hipóxia Encefálica/sangue , Hipóxia Encefálica/diagnóstico por imagem , Hipóxia Encefálica/metabolismo , Vasodilatação , Medições Luminescentes/métodos , Luciferases/genética , Luciferases/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Hipercapnia/sangue , Hipercapnia/diagnóstico por imagem , Hipercapnia/metabolismo
8.
Am J Physiol Endocrinol Metab ; 326(5): E555-E566, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38446637

RESUMO

Prenatal exposure to maternal diabetes has been recognized as a significant cardiovascular risk factor, increasing the susceptibility to the emergence of conditions such as high blood pressure, atherosclerosis, and heart disease in later stages of life. However, it is unclear if offspring exposed to diabetes in utero have worse vascular outcomes on a high-salt (HS) diet. To test the hypothesis that in utero exposure to maternal diabetes predisposes to HS-induced vascular dysfunction, we treated adult male wild-type offspring (DM_Exp, 6 mo old) of diabetic Ins2+/C96Y mice (Akita mice) with HS (8% sodium chloride, 10 days) and analyzed endothelial function via wire myograph and cyclooxygenase (COX)-derived prostanoids pathway by ELISA, quantitative PCR, and immunochemistry. On a regular diet, DM_Exp mice did not manifest any vascular dysfunction, remodeling, or inflammation. However, HS increased aortic contractility to phenylephrine and induced endothelial dysfunction (analyzed by acetylcholine-induced endothelium-dependent relaxation), vascular hydrogen peroxide production, COX2 expression, and prostaglandin E2 (PGE2) overproduction. Interestingly, ex vivo antioxidant treatment (tempol) or COX1/2 (indomethacin) or COX2 (NS398) inhibitors improved or reverted the endothelial dysfunction in DM_Exp mice fed a HS diet. Finally, DM_Exp mice fed with HS exhibited greater circulating cytokines and chemokines accompanied by vascular inflammation. In summary, our findings indicate that prenatal exposure to maternal diabetes predisposes to HS-induced vascular dysfunction, primarily through the induction of oxidative stress and the generation of COX2-derived PGE2. This supports the concept that in utero exposure to maternal diabetes is a cardiovascular risk factor in adulthood.NEW & NOTEWORTHY Using a unique mouse model of prenatal exposure to maternal type 1 diabetes, our study demonstrates the novel observation that prenatal exposure to maternal diabetes results in a predisposition to high-salt (HS) dietary-induced vascular dysfunction and inflammation in adulthood. Mechanistically, we demonstrated that in utero exposure to maternal diabetes and HS intake induces vascular oxidative stress, cyclooxygenase-derived prostaglandin E2, and inflammation.


Assuntos
Diabetes Gestacional , Efeitos Tardios da Exposição Pré-Natal , Humanos , Gravidez , Feminino , Masculino , Camundongos , Animais , Ciclo-Oxigenase 2/metabolismo , Prostaglandinas/metabolismo , Vasodilatação , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Cloreto de Sódio na Dieta/metabolismo , Diabetes Gestacional/metabolismo , Endotélio Vascular/metabolismo , Inflamação/metabolismo
9.
Physiol Rep ; 12(6): e15992, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38538032

RESUMO

Aorta, the largest vessel in the body, is generally considered anatomically homogeneous, yet spatial functional differences exist. In our study, we conducted a comprehensive analysis by reexamining public RNA-SEQ data, comparing expression patterns between thoracic and abdominal aorta. Additionally, we measured acetylcholine-induced relaxations of the different regions of thoracic aorta in Wistar Rats. Our results revealed a distinct percentage difference in acetylcholine-induced relaxation in the proximal and distal segments of the thoracic aorta (p = 1.14e-4). To explain this variation, we performed differential expression analysis of previously published RNA-sequencing data between thoracic and abdominal aorta, which showed 497 differentially expressed genes between these locations. From results of RNA-Seq analysis, we draw a hypothesis that differential expressions of the potassium inward rectifying channels (KIR) and voltage gated calcium channels (VGCC) presumably located on SMC, with higher expression in the distal thoracic segments in comparison with the proximal thoracic segments of aorta, can explain differences in acetylcholine-induced relaxation. Notably, specific blockade of KIR eliminated differences between the proximal and distal regions of thoracic aorta, underscoring their significance in understanding the spatial nuances in aortic behavior, also blockade of VGCC, shows a higher effect on basal tone, in distal region of thoracic aorta in comparison with proximal.


Assuntos
Acetilcolina , Aorta Torácica , Ratos , Masculino , Animais , Acetilcolina/farmacologia , Ratos Wistar , Endotélio Vascular , Vasodilatação , Aorta Abdominal , Canais de Potássio , Canais de Cálcio
10.
Science ; 383(6683): eade8064, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38330107

RESUMO

Penile erection is mediated by the corpora cavernosa, a trabecular-like vascular bed that enlarges upon vasodilation, but its regulation is not completely understood. Here, we show that perivascular fibroblasts in the corpora cavernosa support vasodilation by reducing norepinephrine availability. The effect on penile blood flow depends on the number of fibroblasts, which is regulated by erectile activity. Erection dynamically alters the positional arrangement of fibroblasts, temporarily down-regulating Notch signaling. Inhibition of Notch increases fibroblast numbers and consequently raises penile blood flow. Continuous Notch activation lowers fibroblast numbers and reduces penile blood perfusion. Recurrent erections stimulate fibroblast proliferation and limit vasoconstriction, whereas aging reduces the number of fibroblasts and lowers penile blood flow. Our findings reveal adaptive, erectile activity-dependent modulation of penile blood flow by fibroblasts.


Assuntos
Transportador 1 de Aminoácido Excitatório , Fibroblastos , Ereção Peniana , Pênis , Receptores Notch , Animais , Masculino , Camundongos , Circulação Sanguínea , Transportador 1 de Aminoácido Excitatório/metabolismo , Fibroblastos/metabolismo , Fibroblastos/fisiologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ereção Peniana/fisiologia , Pênis/irrigação sanguínea , Pênis/fisiologia , Receptores Notch/metabolismo , Transdução de Sinais , Vasoconstrição , Vasodilatação
11.
Clin Transl Sci ; 17(2): e13735, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38344891

RESUMO

Buloxibutid (also known as C21) is a potent and selective angiotensin II type 2 receptor (AT2R) agonist, in development for oral treatment of fibrotic lung disease. This phase I, open-label, pharmacodynamic study investigated vascular effects of buloxibutid in five healthy male volunteers. Subjects were administered intra-arterial infusions of buloxibutid for 5 min in ascending doses of 3, 10, 30, 100, and 200 µg/min, infused sequentially in the forearm. Infusions of sodium nitroprusside (SNP) solution in doses of 0.8-3.2 µg/min were administered as a positive control. Forearm blood flow (FBF) was measured by venous occlusion plethysmography. Safety and tolerability of intra-arterial administrations of buloxibutid were evaluated. Following infusion of buloxibutid in doses of 3-200 µg/min, the range of increase in FBF was 27.8%, 17.2%, 37.0%, 28.5%, and 60.5%, compared to the respective baseline. The largest increase was observed in the highest dose group. Infusions of SNP as a positive control, increased FBF 230-320% compared to baseline. Three adverse events (AEs) of mild intensity, not related to buloxibutid or SNP, were reported for two subjects. Two of these AEs were related to study procedures. There were no clinically relevant changes in arterial blood pressure during the study period. Intra-arterial infusion of buloxibutid in low, ascending doses increased FBF, indicating that buloxibutid may be effective in conditions associated with endothelial dysfunction. Venous occlusion plethysmography was found to be a useful method to explore pharmacodynamic vascular effects of novel AT2R agonists, while avoiding systemic adverse effects.


Assuntos
Pletismografia , Receptor Tipo 2 de Angiotensina , Humanos , Masculino , Nitroprussiato/efeitos adversos , Pletismografia/métodos , Antebraço/irrigação sanguínea , Fluxo Sanguíneo Regional , Vasodilatação
12.
Clin Perinatol ; 51(1): 113-126, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38325937

RESUMO

Pulmonary hypertension in the neonatal population can be acute or chronic and carries significant risk for morbidity and mortality. It can be idiopathic but more often is associated with comorbid pulmonary and heart disease. There are several pharmacotherapeutics aimed at pulmonary vasodilation. This review highlights the most common agents as well as those on the horizon for the treatment of pulmonary hypertension in the neonate.


Assuntos
Hipertensão Pulmonar , Óxido Nítrico , Recém-Nascido , Humanos , Óxido Nítrico/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Vasodilatação , Pulmão , Administração por Inalação
13.
Clin Sci (Lond) ; 138(4): 137-151, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38299431

RESUMO

Hypercholesterolemia in pregnancy is a physiological process required for normal fetal development. In contrast, excessive pregnancy-specific hypercholesterolemia increases the risk of complications, such as preeclampsia. However, the underlying mechanisms are unclear. Toll-like receptor 4 (TLR4) is a membrane receptor modulated by high cholesterol levels, leading to endothelial dysfunction; but whether excessive hypercholesterolemia in pregnancy activates TLR4 is not known. We hypothesized that a high cholesterol diet (HCD) during pregnancy increases TLR4 activity in uterine arteries, leading to uterine artery dysfunction. Sprague Dawley rats were fed a control diet (n=12) or HCD (n=12) during pregnancy (gestational day 6-20). Vascular function was assessed in main uterine arteries using wire myography (vasodilation to methacholine and vasoconstriction to phenylephrine; with and without inhibitors for mechanistic pathways) and pressure myography (biomechanical properties). Exposure to a HCD during pregnancy increased maternal blood pressure, induced proteinuria, and reduced the fetal-to-placental weight ratio for both sexes. Excessive hypercholesterolemia in pregnancy also impaired vasodilation to methacholine in uterine arteries, whereby at higher doses, methacholine caused vasoconstriction instead of vasodilation in only the HCD group, which was prevented by inhibition of TLR4 or prostaglandin H synthase 1. Endothelial nitric oxide synthase expression and nitric oxide levels were reduced in HCD compared with control dams. Vasoconstriction to phenylephrine and biomechanical properties were similar between groups. In summary, excessive hypercholesterolemia in pregnancy impairs uterine artery function, with TLR4 activation as a key mechanism. Thus, TLR4 may be a target for therapy development to prevent adverse perinatal outcomes in complicated pregnancies.


Assuntos
Hipercolesterolemia , Hiperlipidemias , Animais , Feminino , Masculino , Gravidez , Ratos , Hipercolesterolemia/metabolismo , Hiperlipidemias/metabolismo , Cloreto de Metacolina/metabolismo , Fenilefrina/farmacologia , Fenilefrina/metabolismo , Placenta , Ratos Sprague-Dawley , Receptor 4 Toll-Like/metabolismo , Artéria Uterina/metabolismo , Vasodilatação/fisiologia
14.
Spinal Cord ; 62(4): 170-177, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38388759

RESUMO

STUDY DESIGN: Acute experimental study. OBJECTIVES: Cold-induced vasodilation is a local mechanism of protection against frostbite in non-injured persons. We assessed whether an increase in skin blood flow (SkBF) during local cooling (LC) was observed in individuals with spinal cord injuries (SCIs) and if the response patterns differed between region levels or sites. SETTING: Laboratory of Wakayama Medical University and the affiliated clinics, Japan. METHODS: A local cooler device (diameter 4 cm) was placed on the chest (sensate) and right thigh (non-sensate) in persons with cervical (SCIC; n = 9) and thoracolumbar SCIs (SCITL; n = 9). After the surface temperature under the device was controlled at 33 °C for 10 min (baseline), LC (-0.045 °C/s) was applied and the skin temperature was maintained at 15 and 8 °C for 15 min of each stage. SkBF (laser Doppler flowmetry) was monitored using a 1-mm needle-type probe inserted into its center. RESULTS: The percent change in SkBF (%ΔSkBF) on the chest remained unchanged until the end of 15 °C stage; thereafter, it increased to a level at least 70% greater than the baseline during the 8 °C stage in both groups. The %ΔSkBF on the thigh in both SCIC and SCITL notably increased from 8 and 6 min respectively, during the 8°C stage, compared to 1 min before the stage; however, it did not exceed the baseline level. CONCLUSIONS: An increase in SkBF during LC was observed both in the sensate and non-sensate areas in SCIs, although the magnitude was larger in the sensate area.


Assuntos
Traumatismos da Medula Espinal , Vasodilatação , Humanos , Vasodilatação/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Pele , Temperatura Cutânea , Fluxometria por Laser-Doppler
15.
J Ethnopharmacol ; 328: 117855, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38346524

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Tea (Camellia sinensis) is a favorite drink worldwide. Tea extracts and green tea main component (-)-epigallocatechin gallate (EGCG) are recommended for various vascular diseases. Anji white tea is a very popular green tea. Its vascular effect profile, the mechanisms, and the contribution of EGCG to its integrated effect need elucidation. AIM: To characterize the vasomotion effects of Anji white tea and EGCG, and to explore possible involvement of voltage-gated Ca2+ channels (VGCCs) and voltage-gated K+ (Kv) channels in their vasomotion effects. MATERIALS AND METHODS: Anji white tea water soaking solution (AJWT) was prepared as daily tea-making process and concentrated to a concentration amounting to 200 mg/ml of dry tea leaves. The tension of rat arteries including aorta, coronary artery (RCA), cerebral basilar artery (CBA), intrarenal artery (IRA), intrapulmonary artery (IPA) and mesenteric artery (MA) was recorded with myographs. In arterial smooth muscle cells (ASMCs) freshly isolated from RCA, the levels of intracellular Ca2+ were measured with Ca2+-sensitive fluorescent probe fluo 4-AM, and Kv currents were recorded with patch clamp. The expressions of VGCCs and Kv channels were assayed with RT-qPCR and immunofluorescence staining. RESULTS: At 0.4-12.8 mg/ml of dry tea leaves, AJWT profoundly relaxed all tested arteries precontracted with various vasoconstrictors about half with a small transient potentiation on the precontractions before the relaxation. KCl-induced precontraction was less sensitive than precontractions induced by phenylephrine (PE), U46619 and serotonin (5-HT). IPA was less sensitive to the relaxation compared with other arteries. AJWT pretreatment for 1 h, 24 h and 72 h time-dependently inhibited the contractile responses of RCAs. In sharp contrast, at equivalent concentrations according to its content in AJWT, EGCG intensified the precontractions in most small arteries, except that it induced relaxation in PE-precontracted aorta and MA, U46619-precontracted aorta and CBA. EGCG pretreatment for 1 h and 24 h did not significantly affect RCA contractile responses. In RCA ASMCs, AJWT reduced, while EGCG enhanced, intracellular Ca2+ elevation induced by depolarization which activates VGCCs. Patch clamp study showed that both AJWT and EGCG reduced Kv currents. RT-qPCR and immunofluorescence staining demonstrated that both AJWT and EGCG reduced the expressions of VGCCs and Kv channels. CONCLUSION: AJWT, but not EGCG, consistently induces vasorelaxation. The vasomotion effects of either AJWT or EGCG vary with arterial beds and vasoconstrictors. Modulation of VGCCs, but not Kv channels, contributes to AJWT-induced vasorelaxation. It is suggested that Anji white tea water extract instead of EGCG may be a promising food supplement for vasospastic diseases.


Assuntos
Catequina/análogos & derivados , Miócitos de Músculo Liso , Chá , Ratos , Animais , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/metabolismo , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Vasodilatação , Vasos Coronários , Artérias Mesentéricas , Vasoconstritores/farmacologia , Água/farmacologia
17.
Vascul Pharmacol ; 154: 107281, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38320678

RESUMO

OBJECTIVE: Perivascular adipose tissue (PVAT) function during aging has not been investigated in detail so far and its effect on vasodilation remains to be fully elucidated. The aim of this study was to investigate endothelium-dependent vasodilation of thoracic aorta in a mouse model of accelerated, selective vascular smooth muscle and PVAT aging, induced by SM22α-Cre-driven genetic deletion of the endonuclease ERCC1 (SMC-KO mice) versus healthy littermates (LM). We hypothesized that PVAT enhances vasodilation in LM, possibly through adiponectin secretion, which might be compromised in SMC-KO animals. METHODS: Thoracic aorta was isolated from SMC-KO animals and LM and segments with and without PVAT were mounted in wire myography setups. The endothelium-dependent vasodilation was assessed via acetylcholine dose-response curves and pathway contribution was studied. Moreover, adiponectin secretion was measured after stimulating the aortic segments with PVAT with acetylcholine. RESULTS: Adiponectin, secreted by PVAT, led to increased NO-contribution to endothelium-dependent vasodilation in healthy LM, although this did not increase maximum relaxation due to loss of EDH. Endothelium-dependent vasodilation was decreased in SMC-KO animals due to reduced NO-contribution and complete EDH loss. Despite strong lipodystrophy the PVAT partially compensated for lost vasodilation in SMC-KO. LM PVAT contained acetylcholinesterase that attenuated acetylcholine responses. This was lost in SMC-KO. CONCLUSIONS: PVAT-derived adiponectin is able to partially compensate for age-related decline in NO-mediated vasodilation, even during strong lipodystrophy, in conditions of absence of compensating EDH. In aorta with healthy PVAT acetylcholinesterase modulates vascular tone, but this is lost during aging, further compensating for decreased acetylcholine responsiveness. Thus, preservation of adiponectin levels, through relatively increased production in lipodystrophic PVAT, and reduction of cholinesterase might be regulatory mechanisms of the PVAT to preserve cholinergic vasodilation during aging.


Assuntos
Lipodistrofia , Vasodilatação , Camundongos , Animais , Adiponectina/genética , Acetilcolinesterase/metabolismo , Acetilcolinesterase/farmacologia , Acetilcolina/farmacologia , Acetilcolina/metabolismo , Músculo Liso Vascular/metabolismo , Tecido Adiposo/metabolismo , Envelhecimento , Lipodistrofia/metabolismo
18.
Zhongguo Zhong Yao Za Zhi ; 49(2): 487-497, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38403324

RESUMO

This study aims to explore the anti-inflammatory, vasodilation, and cardioprotective effects of the intestinal absorption liquids containing Xinshubao Tablets or single herbs, and to elucidate the potential mechanism based on network pharmacology. Western blot was then conducted to validate the expression changes of core proteins. Lipopolysaccharide(LPS)-stimulated RAW264.7 cells were used to observe the anti-inflammatory effect. The vasodilation activity was examined by the microvessel relaxation assay in vitro. Oxygen-glucose deprivation(OGD)-induced H9c2 cells were used to investigate the cardioprotective effect. The chemical components were retrieved from Herb databases and composition of Xinshubao Tablets drug-containing intestinal absorption solution. Drug targets were retrieved from SwissTargetPrediction databases. GeneCards was searched for the targets associated with the anti-inflammatory, vasodilation, and cardioprotective effects. The common targets shared by the drug and the effects were used to establish the protein-protein interaction(PPI) network, from which the core targets were obtained. Finally, the core targets were imported into Cytoscape 3.9.1 for Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) analyses. The anti-inflammatory experiment showed that both Xinshubao Tablets and the single herbs constituting this formula had anti-inflammatory effects. Curcumae Radix had the strongest inhibitory effect on the production of tumor necrosis factor-α(TNF-α), and Salviae Miltiorrhizae Radix et Rhizoma had the strongest inhibitory effect on the generation of interleukin-6(IL-6). Xinshubao Tablets, Curcumae Radix, and Crataegi Fructus had vasodilation effect, and Crataegi Fructus had the strongest effect. Xinshubao Tablets, Salviae Miltiorrhizae Radix et Rhizoma, Acanthopanacis Senticosi Radix et Rhizoma seu Caulis, and Paeoniae Radix Alba had cardioprotective effects, and Salviae Miltiorrhizae Radix et Rhizoma had the strongest cardioprotective effect. Network pharmacology results demonstrated that except the whole formula, Salviae Miltiorrhizae Radix et Rhizoma had the most components with anti-inflammatory effect, and Curcumae Radix had the most components with vasodilation and cardioprotective effects, followed by Salviae Miltiorrhizae Radix et Rhizoma. The nitric oxide synthase 3(NOS3) was predicted as the core target for the anti-inflammatory, vasodilation, and cardioprotective effects. Western blot results showed that Xinshubao Tablets significantly up-regulated the expression of NOS3 in OGD-induced H9c2 cells. GO enrichment analysis showed that the effects were mainly related to lipid exported from cell, regulation of blood pressure, and inflammatory response. KEGG pathway enrichment predicted AGE-RAGE and HIF-1 signaling pathways as the key pathways.


Assuntos
Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/química , Farmacologia em Rede , Vasodilatação , Rizoma/química , Raízes de Plantas/química , Fator de Necrose Tumoral alfa , Medicina Tradicional Chinesa
19.
Biochem J ; 481(5): 387-403, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38373073

RESUMO

The dynamic nature of the microtubule network is dependent in part by post-translational modifications (PTMs) - particularly through acetylation, which stabilizes the microtubule network. Whether PTMs of the microtubule network in vascular smooth muscle cells (VSMCs) contribute to the pathophysiology of hypertension is unknown. The aim of this study was to determine the acetylated state of the microtubule network in the mesenteric arteries of spontaneously hypertensive rats (SHR). Experiments were performed on male normotensive rats and SHR mesenteric arteries. Western blotting and mass spectrometry determined changes in tubulin acetylation. Wire myography was used to investigate the effect of tubacin on isoprenaline-mediated vasorelaxations. Isolated cells from normotensive rats were used for scanning ion conductance microscopy (SICM). Mass spectrometry and Western blotting showed that tubulin acetylation is increased in the mesenteric arteries of the SHR compared with normotensive rats. Tubacin enhanced the ß-adrenoceptor-mediated vasodilatation by isoprenaline when the endothelium was intact, but attenuated relaxations when the endothelium was denuded or nitric oxide production was inhibited. By pre-treating vessels with colchicine to disrupt the microtubule network, we were able to confirm that the effects of tubacin were microtubule-dependent. Using SICM, we examined the cell surface Young's modulus of VSMCs, but found no difference in control, tubacin-treated, or taxol-treated cells. Acetylation of tubulin at Lys40 is elevated in mesenteric arteries from the SHR. Furthermore, this study shows that tubacin has an endothelial-dependent bimodal effect on isoprenaline-mediated vasorelaxation.


Assuntos
Anilidas , Ácidos Hidroxâmicos , Hipertensão , Tubulina (Proteína) , Ratos , Animais , Masculino , Ratos Endogâmicos WKY , Acetilação , Isoproterenol/farmacologia , Ratos Endogâmicos SHR , Artérias Mesentéricas , Vasodilatação , Microtúbulos , Endotélio Vascular/fisiologia
20.
Physiol Rep ; 12(3): e15943, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38311364

RESUMO

Inspiratory resistance training (IRT) yields significant reductions in resting blood pressure and improves vascular endothelial function. Our objective was to quantify the acute effects of IRT on brachial artery flow-mediated dilation (FMD) and shear rates (SRs) in healthy men and women. Twenty young adults (22.9 ± 3.4 years; 10 male, 10 female) completed a single bout of IRT or Rest condition in a randomized crossover design. Brachial artery FMD was performed before, 10 min after, and 40 min after the assigned condition. Brachial artery blood flow velocities were collected during IRT, separated by breathing cycle phase, and converted into SRs. FMD improved 10 min post-IRT (+1.86 ± 0.61%; p = 0.025) but returned to baseline by 40 min post-IRT (p = 0.002). Anterograde SR decreased by 10% and retrograde SR increased 102% during resisted inspiration, relative to baseline SR (p < 0.001). Anterograde SR increased by 7% in men and women (p < 0.001) and retrograde SR decreased by 12% in women but not men (p = 0.022) during unresisted expiration, relative to baseline SR. A single bout of IRT elicits a transient enhancement in FMD in both men and women. Acute IRT-related enhancements in SRs may contribute to sustained improvements in FMD that have been reported previously.


Assuntos
Treinamento de Força , Vasodilatação , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Velocidade do Fluxo Sanguíneo/fisiologia , Artéria Braquial/fisiologia , Estudos Cross-Over , Dilatação , Endotélio Vascular/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Estresse Mecânico , Vasodilatação/fisiologia
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