Marfan syndrome (MFS) is a systemic connective tissue disorder stemming from mutations in the gene encoding Fibrillin-1 (Fbn1), a key extracellular matrix glycoprotein. This condition manifests with various clinical features, the most critical of which is the formation of aortic root aneurysms. Reduced nitric oxide (NO) production due to diminished endothelial nitric oxide synthase (eNOS) activity has been linked to MFS aortic aneurysm pathology.
View Article and Find Full Text PDFSeveral reports, including our previous studies, indicate that hyperglycemia and diabetes mellitus exert differential effects on vascular function in males and females. This study examines sex differences in the vascular effects of type 2 diabetes (T2D) in an established monogenic model of obesity-induced T2D, Zucker Diabetic Fatty (ZDF) rats. Acetylcholine (ACh) responses were assessed in phenylephrine pre-contracted rings before and after apocynin, a NADPH oxidase (NOX) inhibitor.
View Article and Find Full Text PDFThe beneficial cardiovascular effects of exercise are well documented, however the mechanisms by which exercise improves vascular function in diabetes are not fully understood. This study investigates whether there are (1) improvements in blood pressure and endothelium-dependent vasorelaxation (EDV) and (2) alterations in the relative contribution of endothelium-derived relaxing factors (EDRF) in modulating mesenteric arterial reactivity in male UC Davis type-2 diabetes mellitus (UCD-T2DM) rats, following an 8-week moderate-intensity exercise (MIE) intervention. EDV to acetylcholine (ACh) was measured before and after exposure to pharmacological inhibitors.
View Article and Find Full Text PDFWe recently reported sex differences in mesenteric arterial function of the UC Davis type-2 diabetes mellitus (UCD-T2DM) rats as early as the prediabetic state. We reported that mesenteric arteries (MA) from prediabetic male rats exhibited a greater impairment compared to that in prediabetic females. However, when females became diabetic, they exhibited a greater vascular dysfunction than males.
View Article and Find Full Text PDFCardiovascular diseases (CVD) remain the leading cause of death in men and women. Biological sex plays a major role in cardiovascular physiology and pathological cardiovascular remodeling. Traditionally, pathological remodeling of cardiovascular system refers to the molecular, cellular, and morphological changes that result from insults, such as myocardial infarction or hypertension.
View Article and Find Full Text PDFPrevious reports suggest that diabetes may differentially affect the vascular beds of females and males. The objectives of this study were to examine whether there were (1) sex differences in aortic function and (2) alterations in the relative contribution of endothelium-derived relaxing factors in modulating aortic reactivity in UC Davis Type 2 Diabetes Mellitus (UCD-T2DM) rats. Endothelium-dependent vasorelaxation (EDV) in response to acetylcholine (ACh) was measured in aortic rings before and after exposure to pharmacological inhibitors.
View Article and Find Full Text PDFIntroduction: Lung cancer leads in mortality among all types of cancer in US and Non-small cell lung cancer (NSCLC) is the major type of lung cancer. Mice models of lung cancer based on subcutaneous or orthotopic inoculation of cancer cell suspension do not adequately mimic the progression of lung cancer in clinic.
Methods: A549-iRFP cells (human NSCLC adenocarcinoma) were cultured to form multicellular spheroids (MCS), which were then inoculated intrapulmonarily into male athymic nude mice.
Previous reports suggest that diabetes may differentially affect the vascular beds of females and males. However, there is insufficient evidence to establish the timeline of the vascular dysfunction in diabetes, specifically in relation to sex. Here, we determined whether mesenteric arterial function is altered in UC Davis Type-2 Diabetes Mellitus (UCD-T2DM) rats and if this occurs as early as the pre-diabetic stage of the disease.
View Article and Find Full Text PDFWe have recently shown that type of supplemented simple sugar, not merely calorie intake, determines adverse effects on metabolism and aortic endothelial function in female rats. The aim of the current study was to investigate and compare the effects of high consumption of glucose or fructose on mesenteric arterial reactivity and systolic blood pressure (SBP). Sprague-Dawley female rats were supplemented with 20% w/v glucose or fructose in drinking water for 8 weeks.
View Article and Find Full Text PDFUnlabelled: High consumption of simple sugars causes adverse cardiometabolic effects. We investigated the mechanisms underlying the metabolic and vascular effects of glucose or fructose intake and determined whether these effects are exclusively related to increased calorie consumption. Female Sprague-Dawley rats were supplemented with 20% wt/vol glucose or fructose for 2 mo, and plasma analytes and aortic response to vasodilator and vasoconstrictor agents were determined.
View Article and Find Full Text PDFHyperglycemia affects male and female vascular beds differently. We have previously shown that 1 week after the induction of diabetes with streptozotocin (STZ), male and female rats exhibit differences in aortic endothelial function. To examine this phenomenon further, aortic responses were studied in male and female rats 8 weeks after the induction of diabetes (intermediate stage).
View Article and Find Full Text PDFLittle is known of the interactions between diabetes and sex hormones on vascular function. The objectives of this study were to investigate whether there were sex differences in rat aortic endothelial function one week after the induction of streptozotocin (STZ)-diabetes, and to examine the potential roles of superoxide and nitric oxide (NO) in this sex-specific effect. Endothelium-dependent vasodilatation to acetylcholine (ACh) was measured in rat aortic rings before and after treatment with MnTMPyP (25µM), a superoxide dismutase.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
November 2012
Several studies suggest that diabetes affects male and female vascular beds differently. However, the mechanisms underlying the interaction of sex and diabetes remain to be investigated. This study investigates whether there are 1) sex differences in the development of abnormal vascular responses and 2) changes in the relative contributions of endothelium-derived relaxing factors in modulating vascular reactivity of mesenteric arteries taken from streptozotocin (STZ)-induced diabetic rats at early and intermediate stages of the disease (1 and 8 wk, respectively).
View Article and Find Full Text PDFIn an effort to develop pH-sensitive lipoplexes for efficient gene delivery, we report three novel cationic lipids containing a linear ortho ester linker that conjugates either the headgroup (Type I) or one hydrocarbon chain (Type II) with the rest of the lipid molecule. The cationic lipids carry either an iodide or a chloride counterion. Compared to our previously reported cyclic ortho ester linker, the linear ortho ester linker facilitated the construction of cationic liposomes and lipoplexes with different helper lipids.
View Article and Find Full Text PDFRecent evidence showed that 17 β-estradiol (E₂) decreased cytokine-induced expression of cell adhesion molecules (CAM). Changes in intracellular Ca²+ concentration ([Ca²+](i)) has been shown to be associated with CAM expression in endothelial cells. Here, the effects of E₂ (1 μM, 24 h) on the expression of intracellular adhesion molecule-1 (ICAM-1) and [Ca²+](i) were investigated in a lipopolysaccharide (LPS) (100 ng/mL, 18 h)-stimulated human endothelial cell line, EA.
View Article and Find Full Text PDFObjectives: Submandibular vasodilatory responses are impaired in male streptozotocin-diabetic rats. However, the effects of diabetes on submandibular vascular reactivity in female rats have not been examined. The purpose of this study was to determine whether there are gender differences in the effects of diabetes on parasympathetic vasodilatation in the rat submandibular gland.
View Article and Find Full Text PDFThe cardiovascular effects of estrogen are mediated in part by augmenting the function of endothelial nitric oxide synthase. Endothelial nitric oxide synthase activity is dependent on many cofactors including Ca(2+). Hence, we investigated the effect of chronic 17 beta-estradiol treatment on the intracellular Ca(2+) concentration and endothelial nitric oxide synthase protein expression in the human endothelial cell line, EA.
View Article and Find Full Text PDFPrevious studies suggest that NO- and PGI(2)-independent pathways play a greater role in parasympathetic vasodilatation in the submandibular glands (SMG) of female than of male rats. Thus, the purpose of this study was to determine whether estrogen and progesterone influence the relative contributions of NO and PGI(2) to parasympathetic vasodilatation in the SMG. Vascular responses to chorda-lingual nerve stimulation were examined in sham-operated (SHAM) and ovariectomized (OVX) female rats and in OVX rats treated with either 17beta-estradiol alone or a combination of 17beta-estradiol and progesterone.
View Article and Find Full Text PDFEpidemiological data suggest that hyperglycemia abrogates the gender-based cardiovascular protection possibly associated with estrogens. This study was designed to investigate 1) whether rabbit aortic rings show gender differences in the development of abnormal endothelium-dependent vasodilation (EDV) under acute hyperglycemic conditions, 2) the potential role of PKC isoforms and superoxide (O2-) in acute hyperglycemia-induced vascular dysfunction, and 3) the effect of acute estrogen administration on hyperglycemia-induced endothelial dysfunction in male and female rabbits. EDV to ACh was determined before and after 3 h of treatment with high glucose (HG) in phenylephrine-precontracted aortic rings from male and female New Zealand White rabbits.
View Article and Find Full Text PDFObjectives: Several reports suggest that acute hyperglycemia affects male and female vascular beds differently. However, little is known about the interactions between hyperglycemia and gender in the vasculature. The objectives of our study were to investigate if there is a gender-based difference in the relaxation response of rat aorta after acute exposure to high glucose concentration, and the potential role of protein kinase C-beta (PKCbeta), superoxide, and Rho kinase in the gender-specific effect of acute high glucose on the relaxation response.
View Article and Find Full Text PDFParasympathetic vasodilatation in the rat submandibular gland is mediated by nitric oxide-dependent and -independent mechanisms (prostacyclin and endothelium-derived hyperpolarizing factor (EDHF)). The purpose of this study was to determine the influence of gender on the relative contributions of each pathway to nerve-stimulated vasodilatation. Absolute increases in perfusion (laser Doppler flowmetry) were similar in male and female rats (in arbitrary perfusion units: 6159+/-4530 and 5601+/-3877 at 2 Hz; 15645+/-6830 and 14848+/-6118 at 5 Hz; and 22418+/-7660 and 18878+/-5864 at 10 Hz).
View Article and Find Full Text PDFBasal calcium leak into smooth muscle was identified 30 years ago yet remains poorly understood. We characterized this leak measuring 45Ca2+ uptake into cultured rat aortic smooth muscle cells. Wash solution (0 degrees C) containing lanthanum (3 mM) removed extracellular tracer and increased cellular 45Ca2+ retention more effectively than EGTA (0.
View Article and Find Full Text PDFWe have further characterized the Ca2+ signalling properties of the NG115-401L (or 401L) neuroblastoma cell line, which has served as an important cell line for investigating SOC (store-operated channel) influx pathways. These cells possess an unusual Ca2+ signalling phenotype characterized by the absence of Ca2+ influx when Ca2+ stores are depleted by inhibitors of SERCA (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase). Previous studies found that Ca2+-store depletion does not produce a CIF (Ca2+ influx factor) activity in 401L cells.
View Article and Find Full Text PDFBiochem Biophys Res Commun
September 2004
We report the modulatory effects of estrogen on release of endothelium-derived relaxing factors (EDRFs) in a human endothelial cell line, EA.hy926. Using bioassay, we showed that EA.
View Article and Find Full Text PDF