Endothelium-derived hyperpolarizing factor (EDHF) is an important vasodilator that regulates the vasomotor function. However, it remains unclear whether diabetes/hyperglycemia-induced vascular impairments extend to the EDHF. The present study aims to determine the effect of high glucose (HG) on EDHF-mediated arteriolar dilation and the underlying mechanism. Porcine coronary arterioles were isolated and pressurized for vasomotor study. Cultured porcine coronary artery endothelial cells (ECs) were used for molecular and biochemical analysis. Our results demonstrate that bradykinin (BK)-simulated arteriolar dilation is mediated by nitric oxide (NO) and EDHF pathways. Direct incubation of HG impaired vasodilation to BK but not to sodium nitroprusside (endothelium-independent vasodilator). In the presence of inhibitors of endothelial NO synthase (eNOS) and cyclooxygenase, the EDHF-mediated dilation was reduced by HG incubation. The inhibitory effect of HG was prevented by treating the vessels with superoxide scavenger Tempol. In cultured coronary endothelial cells, HG reduced endothelial epoxyeicosatrienoic acid (EET) production as well as cytochrome P450 epoxygenase (CYP) activity. Furthermore, the superoxide production was elevated in ECs after HG incubation. Pretreatment with Tempol before HG incubation prevented the increase of cellular superoxide and abolished the decrease of CYP activity. Collectively, our results suggest that, in addition to NO-mediated pathway, HG impairs the EET/EDHF-mediated vasodilation in coronary arterioles via the elevated level of superoxide leading to inhibition of CYP activity in coronary ECs.
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http://dx.doi.org/10.1016/j.mvr.2011.09.008 | DOI Listing |
Nutrients
January 2025
Department of Obstetrics and Gynaecology, Semmelweis University, Üllői Street 78/a, 1082 Budapest, Hungary.
Background/objectives: Both hyperandrogenism (HA) and vitamin D deficiency (VDD) can separately lead to impaired vascular reactivity and ovulatory dysfunction in fertile females. The aim was to examine the early interactions of these states in a rat model of PCOS.
Methods: Four-week-old adolescent female rats were divided into four groups: vitamin D (VD)-supplemented ( = 12); VD-supplemented and testosterone-treated ( = 12); VDD- ( = 11) and VDD-and-testosterone-treated ( = 11).
Antioxidants (Basel)
January 2025
Laboratory of Molecular Cardiology, Department of Cardiology 1, University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany.
Noise pollution is a known health risk factor and evidence for cardiovascular diseases associated with traffic noise is growing. At least 20% of the European Union's population lives in noise-polluted areas with exposure levels exceeding the recommended limits of the World Health Organization, which is considered unhealthy by the European Environment Agency. This results in the annual loss of 1.
View Article and Find Full Text PDFEMBO J
January 2025
Division of Pulmonary Medicine, Boston Children's Hospital, Boston, MA, 02115, USA.
Pericytes are essential for capillary stability and homeostasis, with impaired pericyte function linked to diseases like pulmonary arterial hypertension. Investigating pericyte biology has been challenging due to the lack of specific markers, making it difficult to distinguish pericytes from other stromal cells. Using bioinformatic analysis and RNAscope, we identified Higd1b as a unique gene marker for pericytes and subsequently generated a knock-in mouse line, Higd1b-CreERT2, that accurately labels pericytes in the lung and heart.
View Article and Find Full Text PDFMicrocirculation
January 2025
Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, UK.
Objective: Cerebral blood flow (CBF) decline is increasingly recognized as an area of importance for targeting neurodegenerative disorders, yet full understanding of the mechanisms that underlie CBF changes are lacking. Animal models are crucial for expanding our knowledge as methods for studying global CBF and neurovascular coupling in humans are limited and require expensive specialized scanners.
Methods: Use of appropriate animal models can increase our understanding of cerebrovascular function, so we have combined chronic cranial windows with in vivo two-photon and laser speckle microscopy and ex vivo capillary-parenchymal arteriole (CaPA) preparations.
Int J Mol Sci
December 2024
Dipartimento di Biotecnologie e Scienze della Vita, ASST Sette Laghi, Università degli Studi dell'Insubria, 21100 Varese, Italy.
Hypertension exerts a profound impact on the microcirculation, causing both structural and functional alterations that contribute to systemic and organ-specific vascular damage. The microcirculation, comprising arterioles, capillaries, and venules with diameters smaller than 20 μm, plays a fundamental role in oxygen delivery, nutrient exchange, and maintaining tissue homeostasis. In the context of hypertension, microvascular remodeling and rarefaction result in reduced vessel density and elasticity, increasing vascular resistance and driving end-organ damage.
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