Differential Deleterious Impact of Highly Saturated Versus Monounsaturated Fat Intake on Vascular Function, Structure, and Mechanics in Mice.

Vegetable oils such as palm oil (enriched in saturated fatty acids, SFA) and high-oleic-acid sunflower oil (HOSO, containing mainly monounsaturated fatty acids, MUFA) have emerged as the most common replacements for trans-fats in the food industry. The aim of this study is to analyze the impact of SFA and MUFA-enriched high-fat (HF) diets on endothelial function, vascular remodeling, and arterial stiffness compared to commercial HF diets. Five-week-old male C57BL6J mice were fed a standard (SD), a HF diet enriched with SFA (saturated oil-enriched Food, SOLF), a HF diet enriched with MUFA (unsaturated oil-enriched Food, UOLF), or a commercial HF diet for 8 weeks. Vascular function was analyzed in the thoracic aorta. Structural and mechanical parameters were assessed in mesenteric arteries by pressure myography. SOLF, UOLF, and HF diet reduced contractile responses to phenylephrine and induced endothelial dysfunction in the thoracic aorta. A significant increase in the ß-index, and thus in arterial stiffness, was also detected in mesenteric arteries from the three HF groups, due to enhanced deposition of collagen in the vascular wall. SOLF also induced hypotrophic inward remodeling. In conclusion, these data demonstrate a deleterious effect of HF feeding on obesity-related vascular alterations that is exacerbated by SFA.

Influence of enhanced bioavailable curcumin on obesity-associated cardiovascular disease risk factors and arterial function: A double-blinded, randomized, controlled trial.

OBJECTIVES: This study aimed to determine whether an enhanced bioavailable curcumin formulation, CurQfen®, would improve circulating cardiovascular disease-related blood biomarkers and arterial function in young (age 18-35 y), obese (body mass index ≥ 30.0 kg/m2) men. METHODS: This double-blinded, placebo-controlled trial evaluated 22 men. The participants were matched based on body mass index and randomized to the intervention (curcumin formulated with fenugreek soluble fiber, for enhanced absorption) or control (fenugreek soluble fiber) group for 12 wk at 500mg/d without dietary modification or exercise. Blood samples and endothelial function measures were acquired at 0 and 12 wk, and blood samples were analyzed for cardiovascular disease-related blood biomarkers. Furthermore, central (aortic) blood pressure and augmentation index were monitored at 0, 4, 8, and 12 wk. RESULTS: After 12 wk of intervention, homocysteine levels were lower (curcumin before: 12.22 ± 2.29 µg/mL, after: 8.62 ± 1.02 µg/mL versus placebo before: 9.45 ± 0.84 µg/mL, after: 11.84 ± 1.63 µg/mL; P = 0.04) and high-density lipoprotein levels were higher (curcumin before: 40.77 ± 5.37 mg/dL, after: 54.56 ± 11.72 mg/dL versus placebo before: 61.20 ± 5.76 mg/dL, after: 48.82 ± 5.49 mg/dL; P = 0.04) in the curcumin group relative to the placebo group. However, there was no significant difference in changes between the circulating concentrations of glucose, insulin, leptin, adiponectin, or oxidative stress biomarkers in the curcumin group compared with the placebo group (P > 0.05). No changes were found with endothelial function, augmentation index, or central blood pressure in the curcumin group compared with the placebo group (P > 0.05). CONCLUSIONS: Our data provide evidence for an enhanced bioavailable curcumin to improve homocysteine and high-density lipoprotein concentrations, which may promote favorable cardiovascular health in young, obese men. Improvements in endothelial function or blood pressure were not observed with curcumin supplementation, thus further investigation is warranted.

Fenugreek (Trigonella Foenum-Graecum) Seed Flour and Diosgenin Preserve Endothelium-Dependent Arterial Relaxation in a Rat Model of Early-Stage Metabolic Syndrome.

Fenugreek is a common herb possessing several bioactive components including diosgenin. Here, dietary fenugreek seed flour and diosgenin were evaluated on a model of endothelium-dependent vasorelaxation by abdominal aortas isolated from rats receiving high-fat, high-sugar diet (HFHSD). 60 male Wistar rats were randomized into six groups: (i) negative control getting conventional rat feed regimen; (ii) positive control receiving HFHSD; (iii) a test group fed 2 g/kg bw/day fenugreek seed flour (containing 10 mg/kg bw/day diosgenin) + HFHSD; (iv) three test groups fed 1, 10 and 50 mg/kg bw/day diosgenin + HFHSD. Alimentary treatments were carried out for six weeks. The abdominal aortas were isolated, and 2 mm wide rings were sectioned off and mounted at a resting tension of 10 mN in organ baths containing Krebs solution (36 °C) exposed to 95% O2 and 5% CO2. After 60-min incubation, a norepinephrine concentration-response (E/c) curve was generated to determine their half-maximal effective concentration (EC50) value. After 60-min wash-out, a pre-contraction with norepinephrine EC50 was made, followed by an acetylcholine E/c curve. Plasma glutathione levels, glutathione-handling enzyme activities and blood antioxidant capacities were also determined. HFHSD significantly decreased the dilatory response to acetylcholine and increased plasma glutathione levels and these effects were significantly reversed by fenugreek seed flour, 10 and 50 mg/kg bw/day diosgenin. Both fenugreek and diosgenin treatments prevent HFHSD-induced endothelial dysfunction and redox changes. As fenugreek treatment was more effective at lower acetylcholine concentrations than diosgenin treatments, components of fenugreek other than diosgenin may contribute to the beneficial effects of dietary fenugreek seed flour.

The influence of low level laser irradiation on vascular reactivity.

PURPOSE: The mechanism of action of low level laser irradiation on tissues is unclear. Authors of publications present the positive clinical impact of low and medium power laser irradiation on vascular reactivity. The purpose of this study was to analyze the role of vascular endothelium in laser-induced constricted by endothelin-1 and phenylephrine. MATERIALS AND METHODS: Experiments were performed on isolated and perfused rat tail arteries of weighing 250-350g male Wistar rats. Contractility of arteries as a response to endothelin-1 and phenylephrine was measured after exposure to laser stimulation (10, 30 and 110mW). RESULTS: Laser irradiation inhibits vascular smooth muscle contraction induced by endothelin-1 and an alpha-adrenergic receptor agonist, phenylephrine proportionally to the laser power. Concentration-response curves were shifted to the right with significant reduction in maximal response. Laser irradiation at the power of 10mW, 30mW, and 110mW reduced the maximum response of arteries stimulated with phenylephrine sequentially to 88%, 72%, and 52%. Similar findings were observed during stimulation of endothelin-1. Laser irradiation at the power of 10mW, 30mW and 110mW resulted in maximal response respectively reduced to 94%, 62% and 38%. CONCLUSION: Our results strongly suggest that during low level laser irradiation vascular smooth muscle cells reactivity is reduced, this effect is present in arteries with normal endothelium. The mechanism of action of laser biosimulation on tissues is unclear. Authors of publications present the positive clinical impact of low level laser irradiation on vascular reactivity.

Seeds of Buchholzia coriacea in Diet Mitigate Ischemic Reperfusion-Induced Gastric Ulceration in Experimental Rats.

Buchholzia coriacea (B. coriacea) seeds, in folk medicine, have been documented to prevent gastric ulceration though the mechanism is not fully elucidated. To clarify this, the gastro-healing activities were investigated using graded incorporation of B. coriacea seeds in the diet. Male Wistar rats (150-200 g) were divided into 7 groups (n = 15): unulcerated untreated control, ulcerated untreated control, unulcerated B. coriacea low (10%), ulcerated B. coriacea low (10%), nulcerated B. coriacea high (25%), ulcerated B. coriacea high (25%), and ulcerated omeprazole-treated groups. Rats were fed with B. coriacea diets for 7 weeks; thereafter, ulcer was induced by ischemic reperfusion method. Daily body weight, gastric acid secretion, hematological parameters, stomach ulcer score, and biochemical and histological analyses were evaluated on days 0, 3, and 7 post-ulcer induction. Results were subjected to one-way analysis of variance (ANOVA) and presented as mean ± standard error of the mean (SEM); p ≤.05 was considered significant. Significant decreases were observed in mean body weight of B. coriacea-fed compared with control and omeprazole-treated groups from week 7. Ulcerated B. coriacea-fed showed significant decrease in gastric acid secretion by days 3 and 7 compared with ulcerated control groups. Malondialdehyde content was significantly decreased in ulcerated B. coriacea-fed compared with control and omeprazole-treated groups. Significant increases in hematological variables (notably platelet count), superoxide dismutase, catalase, and nitric oxide levels of B. coriacea-fed compared with control and omeprazole-treated groups by days 0 and 3 were observed. Histological evaluations further confirmed these observations. B. coriacea diet enhanced gastric healing activities on ischemic reperfused gastric ulcer. Increased platelet count and nitric oxide levels may play significant roles in this process.

Role of thromboxane A2 signaling in endothelium-dependent contractions of arteries.

Thromboxane A2 (TxA2) plays a very important role in various cardiovascular diseases through its action on platelet aggregation, vasoconstriction, and proliferation. The present article focuses on the role of TxA2 signaling in endothelium-dependent contractions of arteries. Arachidonic acid (AA) is metabolized by cyclooxygenase (COX) to form the unstable prostaglandin H2 which is further converted into TxA2. After being produced by thromboxane synthase (TxAS), TxA2 ultimately stimulates TxA2/prostanoid (TP) receptor to induce vasoconstriction. The calcium ionophore A23187, the prostanoid precursor AA, or the muscarinic receptor agonist acetylcholine (ACh) can evoke endothelium-dependent contractions associated with TxA2. The endothelium-dependent contractions shown in hypertension, diabetes, atherogenesis, and other cardiovascular diseases have been significantly reduced by antagonism of COX, TxAS, or TP receptor. So inhibition of the bioavailability and/or effect of TxA2 may be promising therapeutic targets to prevent these diseases. Especially some bioactive compounds isolated from medicinal plants will provide new pharmacological approaches to promote vascular health.

Antioxidant and vasorelaxant activities induced by northeastern Brazilian fermented grape skins.

BACKGROUND: In northeastern Brazil, grape pomace has become a potential alternative byproduct because of the recover phenolic compounds from the vinification process. Comparative analyses were performed between lyophilized extract of grape skins from pomace, described as fermented (FGS), and fresh, unfermented (UGS) grape skins to show the relevant brand's composition upon the first maceration in winemaking. METHODS: The use of in vitro testing such as Folin-Ciocalteu's, DPPH free radical scavenger and HPLC methods were performed to evidence antioxidant effect and phenolic compounds. Additionally, vascular reactivity studies were performed in third-order branches of rat superior mesenteric arteries, which were obtained and placed in organ baths containing Krebs-Henseleit solution, maintained at 37 °C, gassed with a mixture of 95% O2 and 5% CO2, and maintained at pH 7.4. The in situ formation of reactive oxygen species (ROS) was evaluated in small mesenteric rings using oxidative fluorescent dihydroethidium dye. RESULTS: We found higher phenolic content and antioxidant activity in FGS when compared to UGS. HPLC analyses identified a significant number of phenolic compounds with antioxidant potential in both samples. The vasorelaxant effect induced by FGS was more potent than that induced by UGS, and the activity was attenuated after removal of vascular endothelium or by blockade of endothelium-derived relaxing factors, such as NO and EDHF. CONCLUSIONS: The FGS extract may be a great source of natural polyphenol products with potent antioxidant effects and endothelium-dependent vasodilatory actions involving NO and EDHF pathways.

Characterization of pressure-mediated vascular tone in resistance arteries from bile duct-ligated rats.

In cirrhosis, changes in pressure-mediated vascular tone, a key determinant of systemic vascular resistance (SVR), are unknown. To address this gap in knowledge, we assessed ex vivo dynamics of pressurized mesenteric resistance arteries (diameter ~ 260 µm) from bile duct-ligated (BDL) and sham-operated (SHAM) rats and determined the underlying mechanisms. At isobaric intraluminal pressure (70 mmHg) as well as with step-wise increase in pressure (10-110 mmHg), arteries from SHAM-rats constricted more than BDL-rats, and had reduced luminal area. In both groups, incubation with LNAME (a NOS inhibitor) had no effect on pressure-mediated tone, and expression of NOS isoforms were similar. TEA, which enhances Ca2+ influx, augmented arterial tone only in SHAM-rats, with minimal effect in those from BDL-rats that was associated with reduced expression of Ca2+ channel TRPC6. In permeabilized arteries, high-dose Ca2+ and γGTP enhanced the vascular tone, which remained lower in BDL-rats that was associated with reduced ROCK2 and pMLC expression. Further, compared to SHAM-rats, in BDL-rats, arteries had reduced collagen expression which was associated with increased expression and activity of MMP-9. BDL-rats also had increased plasma reactive oxygen species (ROS). In vascular smooth muscle cells in vitro, peroxynitrite enhanced MMP-9 activity and reduced ROCK2 expression. These data provide evidence that in cirrhosis, pressure-mediated tone is reduced in resistance arteries, and suggest that circulating ROS play a role in reducing Ca2+ sensitivity and enhancing elasticity to induce arterial adaptations. These findings provide insights into mechanisms underlying attenuated SVR in cirrhosis.

Bone Mineral Density Is Positively Related to Carotid Intima-Media Thickness: Findings From a Population-Based Study in Adolescents and Premenopausal Women.

Osteoporosis and cardiovascular disease (CVD) are both common causes of morbidity and mortality. Previous studies, mainly of people older than 60 years, suggest a relationship between these conditions. Our aim was to determine the association between bone characteristics and CVD markers in younger and middle-aged individuals. Women (n = 3366) and their adolescent offspring (n = 4368) from the UK population-based cohort study, Avon Longitudinal Study of Parents and Children (ALSPAC), were investigated. We measured total body (TB) and hip bone mineral density (BMD), TB bone area (BA) and bone mineral content (BMC) by dual-energy X-ray absorptiometry (DXA), and carotid intima-media thickness (cIMT) by high-resolution ultrasound. Arterial distensibility was calculated as the difference between systolic and diastolic arterial diameters. Linear regression determined associations between bone exposures and cIMT (in adolescents) and both cIMT and arterial distensibility (in women), generating partial correlation coefficients. Mean (SD) age of women was 48 (4.2) years, body mass index (BMI) was 26.2 (5.0) kg/m2 , and 71% were premenopausal. In confounder-adjusted analyses (age, height, lean mass, fat mass, menopause, smoking, estrogen replacement, calcium/vitamin D supplementation, and education) TB and hip BMD were both positively associated with cIMT (0.071 [0.030, 0.112], p = 0.001; 0.063 [0.025, 0.101], p = 0.001, respectively). Femoral neck BMD and TB BMD, BMC, and BA were positively associated with arterial distensibility. Mean (SD) age of adolescents was 17 (0.4) years, BMI was 23 (4.1) kg/m2 , and 44.5% were male. Total hip and TB measurements were positively associated with cIMT, with similar magnitudes of association to those found in their mothers. In contrast to most published findings, we identified weak positive associations between BMD and cIMT in predominantly premenopausal women and their adolescent offspring. We found greater femoral neck BMD and TB DXA measurements to be associated with reduced arterial stiffness. Rather than a relationship with preclinical atherosclerosis, in these relatively young populations, we speculate our associations between BMD, cIMT, and arterial distensibility may reflect a shared relationship between bone and vascular growth and development. © 2016 American Society for Bone and Mineral Research.

Vitamin D controls resistance artery function through regulation of perivascular adipose tissue hypoxia and inflammation.

Vitamin D deficiency in human subjects is associated with hypertension, metabolic syndrome and related risk factors of cardiovascular diseases. Serum 25-hydroxyvitamin D levels correlate inversely with adiposity in obese and lean individuals. Bioactive vitamin D, or calcitriol, exerts anti-inflammatory effects on adipocytes, preadipocytes and macrophages in vitro. We tested the hypothesis that vitamin D deficiency alters the phenotype of perivascular adipose tissue (PVAT) leading to impaired function in resistance artery. To examine the effects of vitamin D and PVAT on vascular reactivity, myograph experiments were performed on arteries, with or without intact PVAT, from mice maintained on vitamin D-deficient, vitamin D-sufficient or vitamin D-supplemented diet. Systolic blood pressure was significantly increased in mice on vitamin D-deficient diet. Importantly, vitamin D deficiency enhanced angiotensin II-induced vasoconstriction and impaired the normal ability of PVAT to suppress contractile responses of the underlying mesenteric resistance artery to angiotensin II and serotonin. Furthermore, vitamin D deficiency caused upregulation of the mRNA expression of tumor necrosis factor-α, hypoxia-inducible factor-1α and its downstream target lysyl oxidase in mesenteric PVAT. Incubation of mesenteric arteries under hypoxic conditions impaired the anti-contractile effects of intact PVAT on those arteries from mice on vitamin D-sufficient diet. Vitamin D supplementation protected arteries against hypoxia-induced impairment of PVAT function. The protective effects of vitamin D against vascular dysfunction, hypertension and cardiovascular diseases may be mediated, at least in part, through regulation of inflammatory and hypoxia signaling pathways in PVAT.

l-Arginine Supplementation Alleviates Postprandial Endothelial Dysfunction When Baseline Fasting Plasma Arginine Concentration Is Low: A Randomized Controlled Trial in Healthy Overweight Adults with Cardiometabolic Risk Factors.

BACKGROUND: Vascular endothelial dysfunction, the hallmark of early atherosclerosis, is induced transiently by a high-fat meal. High doses of free l-arginine supplements reduce fasting endothelial dysfunction. OBJECTIVE: We sought to determine the effects of a low dose of a sustained-release (SR) l-arginine supplement on postprandial endothelial function in healthy overweight adults with cardiometabolic risk factors and to investigate whether this effect may vary by baseline arginine status. METHODS: In a randomized, double-blind, 2-period crossover, placebo-controlled trial (4-wk treatment, 4-wk washout), we compared the effects of 1.5 g SR-l-arginine 3 times/d (4.5 g/d) with placebo in 33 healthy overweight adults [body mass index (BMI, in kg/m(2)): 25 to >30] with the hypertriglyceridemic waist (HTW) phenotype [plasma triglycerides > 150 mg/dL; waist circumference > 94 cm (men) or > 80 cm (women)]. The main outcome variable tested was postprandial endothelial function after a high-fat meal (900 kcal), as evaluated by use of flow-mediated dilation (FMD) and Framingham reactive hyperemia index (fRHI), after each treatment. By use of subgroup analysis, we determined whether the effect was related to the baseline plasma arginine concentration. RESULTS: In the total population, the effects of SR-arginine supplementation on postprandial endothelial function were mixed and largely varied with baseline fasting arginine concentration (P-interaction < 0.05). In the lower half of the population (below the median of 78.2 µmol arginine/L plasma), but not the upper half, SR-arginine supplementation attenuated the postprandial decrease in both FMD (29% decrease with SR-arginine compared with 50% decrease with placebo) and fRHI (5% increase with SR-arginine compared with 49% decrease with placebo), resulting in significantly higher mean ± SEM values with SR-arginine (FMD: 4.0% ± 0.40%; fRHI: 0.41 ± 0.069) than placebo (FMD: 2.9% ± 0.31%; fRHI: 0.21 ± 0.060) at the end of the postprandial period (P < 0.05). CONCLUSIONS: Supplementation with low-dose SR-arginine alleviates postprandial endothelial dysfunction in healthy HTW adults when the baseline plasma arginine concentration is relatively low. The benefits of arginine supplementation may be linked to a lower ability to mobilize endogenous arginine for nitric oxide synthesis during a postprandial challenge. This trial was registered at clinicaltrials.gov as NCT02354794.

Neural network study for standardizing pulse-taking depth by the width of artery.

To carry out a pulse diagnosis, a traditional Chinese medicine (TCM) physician presses the patient's wrist artery at three incremental depths, namely Fu (superficial), Zhong (medium), and Chen (deep). However, the definitions of the three depths are insufficiently clear for use with modern pulse diagnosis instruments (PDIs). In this paper, a quantitative method is proposed to express the pulse-taking depths based on the width of the artery (WA). Furthermore, an index, α, is developed for estimating WA for PDI application. The α value is obtained using an artificial neural network (ANN) model with contact pressure (CP) and sensor displacement (SD) as the inputs. The WA and SD data from an ultrasound instrument and CP and SD data from a PDI were analyzed. The results show that the mean prediction error and the standard deviation (STD) of the ANN model was 1.19% and 0.0467, respectively. Comparing the ANN model with the SD model by statistical method, it showed significant difference and the improvement in the mean prediction error and the STD was 71.62% and 29.78%, respectively. The α value can thus map WA with less individual variation than that of the values estimated directly using the SD model. Pulse signals at different depths thus can be acquired according to α value while using a PDI, providing TCM physicians with more reliable pulse information.

Effect studies of Uyghur sand therapy on the hemodynamics of the knee-joint arteries.

This paper studies the effect of Uyghur sand therapy on dynamics of arterial flow of knee joints via experiments and numerical simulations. Experiments have been carried out on 30 volunteers, with their diameter and flow rate of arteries of knee joints measured before and after Uyghur sand therapy. It has been found that Uyghur sand therapy will increase the inner diameter of knee arteries and speed up the blood flow. Experimental results show that Uyghur sand therapy can help relieve obstacles in local blood flow. By choosing one volunteer for CT scanning, three-dimensional reconstruction of knee-joint arteries via MIMICS software is achieved. Calculation model is the established with numerical calculations performed by ANSYS software. According to the calculations, the blood flow of the knee arteries speeds up and the uniform distribution of velocity enlarges after Uyghur sand therapy, which further confirms the experimental results. Besides, the research also suggests that Uyghur sand therapy has stronger effect on blood flow of knee-joint arteries than the inner diameter.

Traditional thermal therapy with indirect moxibustion decreases renal arterial resistive index.

OBJECTIVE: To evaluate the immediate effects of indirect moxibustion, a traditional local thermal therapy, on renal hemodynamics by using Doppler ultrasonography (US). DESIGN: Prospective observational study of postintervention changes in several variables. SETTING: Gifu University Hospital, Gifu, Japan. PARTICIPANTS: Eleven healthy persons (7 men and 4 women; mean age±standard deviation, 32.6±5.7 years) were enrolled. INTERVENTION: Indirect moxibustion was applied for 4 minutes to bilateral lower back acupuncture points (BL23). Each participant received 3 successive treatments. OUTCOME MEASURES: The main outcome measurement was resistive index (RI) in the renal segmental arteries. Blood flow variables, including RI, were measured for 6 renal segmental arteries by Doppler US at rest (baseline), immediately after completion of moxibustion (post 1), and 10 minutes later (post 2). Participants were monitored for adverse events during the intervention. RESULTS: The mean RI was 0.578±0.037 at baseline, 0.546±0.027 at post 1, and 0.547±0.032 at post 2. RI decreased significantly between post 1 and baseline (95% confidence interval [CI], -0.053 to -0.011; p=0.003) and between post 2 and baseline (95% CI, -0.052 to -0.009; p=0.005). No adverse events, such as burns, were observed. CONCLUSION: This study of the short-term effects of indirect moxibustion on renal hemodynamics in healthy persons showed that renal vascular resistance was reduced after the therapy.

Influence of L-arginine supplementation on reproductive blood flow and embryo recovery rates in mares.

Supplementation with L-arginine can increase uterine arterial blood flow and vascular perfusion of the preovulatory follicle in mares. Increased vascular perfusion of the preovulatory follicle has been correlated with successful pregnancy in mares. The objective of this study was to determine if supplemental L-arginine would increase ovarian arterial blood flow, vascular perfusion of the preovulatory follicle, and embryo recovery rates in mares. Mares were blocked by age and breed and assigned at random within block to L-arginine supplementation or control groups. Mares were fed L-arginine beginning 17 days before and through the duration of the study. Transrectal Doppler ultrasonography was used to measure ovarian arterial blood flow and vascular perfusion of the preovulatory follicle daily when it reached 35 mm and subsequent CL on Days 2, 4, and 6. Mares, on achieving a follicle of 35 mm or more were bred via artificial insemination and an embryo collection was attempted 7 days after ovulation. Treatment did not affect interovulatory interval (arginine-treated, 18.1 ± 2.6 days; control, 20.7 ± 2.3 days) or embryo recovery rate (arginine-treated, 54%; control, 48%). Mares treated with l-arginine had a larger follicle for the 10 days preceding ovulation than control mares (30.4 ± 1.2 and 26.3 ± 1.3 mm, respectively; P < 0.05) and vascular perfusion of the dominant follicle tended (P = 0.10) to be greater for the 4 days before ovulation. No differences were observed between groups in diameter or vascular perfusion of the CL. Resistance indices, normalized to ovulation, were not significantly different between groups during the follicular or luteal phase. Oral l-arginine supplementation increased the size and tended to increase perfusion of the follicle 1, but had no effect on luteal perfusion or embryo recovery rates in mares.

Effects of Ω-3 fatty acids on endothelial function, arterial wall properties, inflammatory and fibrinolytic status in smokers: a cross over study.

BACKGROUND: Smoking is associated with endothelial dysfunction and arterial stiffness. Supplementation of Ω-3 PUFAs is associated with better prognosis. Aim of this study was to evaluate the effects of Ω-3 polyunsaturated fatty acids (PUFAs) supplementation on smoking-induced impairment of arterial function. METHODS: We studied the effect of a 12 weeks oral treatment with 2gr/day of Ω-3 PUFAs in 20 healthy smokers on three occasions (day 0:baseline, day 28 and day 84). The study was carried out on two separate arms (Ω-3 fatty acids and placebo), according to a randomized, placebo-controlled, double-blind, cross-over design. Measurements were carried out before (pSm), immediately and 20min after cigarette smoking. Endothelial function was evaluated by flow-mediated dilation (FMD) of the brachial artery. Carotid-femoral pulse wave velocity (PWV) was measured as an index of aortic stiffness and augmentation index (AIx) as a measure of arterial wave reflections. Circulating levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and plasminogen activator inhibitor-1 (PAI-1) were measured. RESULTS: Compared with placebo, Ω-3 PUFAs treatment resulted in a significant improvement in pSm values of FMD (p<0.05), AIx (p<0.001) and PWV (p<0.01). Although, acute cigarette smoking decreased FMD and caused an increase in AIx and PWV, Ω-3 PUFAs treatment blunted the acute smoking-induced impairment of FMD (p<0.001), AIx (p<0.05) and PWV (p<0.05) and significantly decreased levels of TNFα (p<0.05) and IL-6 (p=0.01) and increased levels of PAI-1 (p=0.05). CONCLUSIONS: Ω-3 PUFAs improved endothelial function and the elastic properties of the arterial tree in healthy smokers, with a parallel anti-inflammatory effect.

Tai Chi, arterial compliance, and muscle strength in older adults.

BACKGROUND: Aerobic exercise can alleviate the declines in arterial compliance common in older adults. However, when combined with strength training, aerobic exercise may not reduce arterial compliance. Tai Chi practice has been found to improve muscle strength and cardiopulmonary function in older subjects, but whether or not it improves arterial compliance is not known. The primary aim of this study was to investigate whether Tai Chi practitioners have better arterial compliance and muscle strength. DESIGN: Twenty-nine older Tai Chi practitioners (73.7 ± 4.5 years) and 36 healthy control subjects (71.4 ± 6.6 years) participated in this cross-sectional study. METHODS: The participants were independent in their daily living activities. They were screened for apparent cardiovascular disease and underwent arterial compliance testing and isokinetic knee muscle strength testing at 30°/s. RESULTS: Tai Chi practitioners showed significantly better haemodynamic parameters than the controls as indexed by larger and small artery compliance. They also demonstrated greater eccentric muscle strength in both knee extensors and flexors. CONCLUSION: The findings of better muscle strength without jeopardizing arterial compliance suggests that Tai Chi could be a suitable exercise for older persons to improve both cardiovascular function and muscle strength.

Peak systolic velocity of superior thyroid artery for the differential diagnosis of thyrotoxicosis.

AIM: The differentiation of destruction-induced thyrotoxicosis and Graves' disease (GD) is of great importance for selection of proper therapy. Radioactive iodine uptake (RAIU) is the gold standard for differentiating these two conditions but its application has remained somewhat limited. Thyroid color Doppler flow sonography (CDFS) is a potential alternative of RAIU but more supporting evidence is warranted. In the present study, a standard operative procedure was developed to measure the mean peak systolic velocity of superior thyroid artery (STA-PSV) and evaluate its role in the differential diagnosis of thyrotoxicosis. METHODS: A total of 135 patients with untreated thyrotoxicosis were enrolled into one retrospective study (GD, n = 103; thyroiditis, n = 32) and another prospective study recruited 169 patients (GD, n = 118; thyroiditis, n = 51). Thirty normal controls were also enrolled. Thyroid function, anti-TSH-receptor antibody (TRAb), RAIU, CFDS of thyroid and STA-PSV were performed for each patient. Receiver operator curve (ROC) was used to evaluate the diagnostic value of STA-PSV in a retrospective study so as to seek the optimal cutoff point. Then the cutoff point value was used to validate its diagnostic value in a prospective study and in another thyrotoxicosis population. RESULTS: STA-PSV of GD was significantly higher than that of thyroiditis in both retrospective and prospective studies. The area under the ROC curve of mean STA-PSV was 0.8799 and 0.9447 in the retrospective and prospective studies respectively. If a mean STA-PSV cutoff point of 50.5 cm/s was set from the retrospective analysis for the prospective study, the sensitivity and specificity in distinguishing GD from thyroiditis were 81.04% and 96.08% respectively. Mean STA-PSV and TRAb had similar area under ROC. The coefficients of variation in STA-PSV measurement were lower than 10% for the euthyroid, thyroiditis and GD groups. CONCLUSIONS: STA-PSV is a feasible supplement alternative of RAIU for differentiating the causes of thyrotoxicosis.

Vasorelaxing effects of estetrol in rat arteries.

This study compared ex vivo relaxing responses to the naturally occurring human hormone estetrol (E(4)) vs 17ß-estradiol (E(2)) in eight different vascular beds. Arteries were mounted in a myograph, contracted with either phenylephrine or serotonin, and cumulative concentration-response curves (CRCs) to E(4) and E(2) (0·1-100  µmol/l) were constructed. In all arteries tested, E(4) had lower potency than E(2), although the differential effect was less in larger than smaller arteries. In uterine arteries, the nonselective estrogen receptor (ER) blocker ICI 182 780 (1  µmol/l) caused a significant rightward shift in the CRC to both E(4) and E(2), indicating that the relaxation responses were ER dependent. Pharmacological blockade of nitric oxide (NO) synthases by N(ω)-nitro-L-arginine methyl ester (L-NAME) blunted E(2)-mediated but not E(4)-mediated relaxing responses, while inhibition of prostaglandins and endothelium-dependent hyperpolarization did not alter relaxation to either E(4) or E(2) in uterine arteries. Combined blockade of NO release and action with L-NAME and the soluble guanylate cyclase (sGC) inhibitor ODQ resulted in greater inhibition of the relaxation response to E(4) compared with E(2) in uterine arteries. Endothelium denudation inhibited responses to both E(4) and E(2), while E(4) and E(2) concentration-dependently blocked smooth muscle cell Ca(2)(+) entry in K(+)-depolarized and Ca(2)(+)-depleted uterine arteries. In conclusion, E(4) relaxes precontracted rat arteries in an artery-specific fashion. In uterine arteries, E(4)-induced relaxations are partially mediated via an endothelium-dependent mechanism involving ERs, sGC, and inhibition of smooth muscle cell Ca(2)(+) entry, but not NO synthases or endothelium-dependent hyperpolarization.

Inspiratory muscle training abolishes the blood lactate increase associated with volitional hyperpnoea superimposed on exercise and accelerates lactate and oxygen uptake kinetics at the onset of exercise.

We examined the effects of inspiratory muscle training (IMT) upon volitional hyperpnoea-mediated increases in blood lactate ([lac(-)](B)) during cycling at maximal lactate steady state (MLSS) power, and blood lactate and oxygen uptake kinetics at the onset of exercise. Twenty males formed either an IMT (n = 10) or control group (n = 10). Prior to and following a 6-week intervention, two 30 min trials were performed at MLSS (207 ± 28 W), determined using repeated 30 min constant power trials. The first was a reference trial, whereas during the second trial, from 20 to 28 min, participants mimicked the breathing pattern commensurate with 90% of the maximal incremental exercise test minute ventilation ([Formula: see text]). Prior to the intervention, the MLSS [lac(-)](B) was 3.7 ± 1.8 and 3.9 ± 1.6 mmol L(-1) in the IMT and control groups, respectively. During volitional hyperpnoea, [Formula: see text] increased from 79.9 ± 9.5 and 76.3 ± 15.4 L min(-1) at 20 min to 137.8 ± 15.2 and 135.0 ± 19.7 L min(-1) in IMT and control groups, respectively; [lac(-)](B) concurrently increased by 1.0 ± 0.6 (+27%) and 0.9 ± 0.7 mmol L(-1) (+25%), respectively (P < 0.05). Following the intervention, maximal inspiratory mouth pressure increased 19% in the IMT group only (P < 0.01). Following IMT only, the increase in [lac(-)](B) during volitional hyperpnoea was abolished (P < 0.05). In addition, the blood lactate (-28%) and phase II oxygen uptake (-31%) kinetics time constants at the onset of exercise and the MLSS [lac(-)](B) (-15%) were reduced (P < 0.05). We attribute these changes to an IMT-mediated increase in the oxidative and/or lactate transport capacity of the inspiratory muscles.