Atherosclerosis and Endometriosis: The Role of Diet and Oxidative Stress in a Gender-Specific Disorder

Background: Accelerated atherosclerosis in patients with endometriosis has been hypothesised, and lifestyle improvement might control cardiovascular risk. We explored cardiometabolic markers and oxidative stress and evaluated the effects of the Mediterranean Diet (MD) in modulating these markers. Methods: In this prospective study, we included 35 women with endometriosis. At baseline (T0) and after 3 (T1) and 6 (T2) months from the start of the diet, we investigated cardiometabolic parameters, lifestyle and oxidative stress. Results: After a 3-month intervention with MD, we observed a significant reduction in total cholesterol (p = 0.01) and LDL-c (p = 0.003). We observed at T1 an increase in B12 and E vitamins, folate and zinc. After 6 months, zinc (p = 0.04) and folate (p = 0.08) increased in comparison to T0. A reduction in homocysteine from T0 to T1 (p = 0.01) was found. After 3 months, an increase in Rapid Assessment of Physical Activity tool 1 (RAPA) (p < 0.001) and RAPA 2 was observed (p = 0.009). We observed high levels of oxidative stress markers at baseline. After 6 months of MD, a significant improvement in lymphocyte Reactive Oxygen Species (ROS) (p < 0.001) and total antioxidant capacity was observed (p = 0.02). Conclusions: The improvement of lifestyle, and in particular the Mediterranean dietary intervention, allowed the improvement of the metabolic and oxidative profile and overall health-related quality of life.

Association of serum metabolites and gut microbiota at hospital admission with nosocomial infection development in patients with cirrhosis

Cirrhosis is complicated by a high rate of nosocomial infections (NIs), which result in poor outcomes and are challenging to predict using clinical variables alone. Our aim was to determine predictors of NI using admission serum metabolomics and gut microbiota in inpatients with cirrhosis. In this multicenter inpatient cirrhosis study, serum was collected on admission for liquid chromatography-mass spectrometry metabolomics, and a subset provided stool for 16SrRNA analysis. Hospital course, including NI development and death, were analyzed. Metabolomic analysis using analysis of covariance (ANCOVA) (demographics, Model for End-Stage Liver Disease [MELD] admission score, white blood count [WBC], rifaximin, and infection status adjusted) and random forest analyses for NI development were performed. Additional values of serum metabolites over clinical variables toward NI were evaluated using logistic regression. Stool microbiota and metabolomic correlations were compared in patients with and without NI development. A total of 602 patients (231 infection admissions) were included; 101 (17%) developed NIs, which resulted in worse inpatient outcomes, including intensive care unit transfer, organ failure, and death. A total of 127 patients also gave stool samples, and 20 of these patients developed NIs. The most common NIs were spontaneous bacterial peritonitis followed by urinary tract infection, Clostridioides difficile, and pneumonia. A total of 247 metabolites were significantly altered on ANCOVA. Higher MELD scores (odds ratio, 1.05; p < 0.0001), admission infection (odds ratio, 3.54; p < 0.0001), and admission WBC (odds ratio, 1.05; p = 0.04) predicted NI (area under the curve, 0.74), which increased to 0.77 (p = 0.05) with lower 1-linolenoyl-glycerolphosphocholine (GPC) and 1-stearoyl-GPC and higher N-acetyltryptophan and N-acetyl isoputreanine. Commensal microbiota were lower and pathobionts were higher in those who developed NIs. Microbial-metabolite correlation networks were complex and dense in patients with NIs, especially sub-networks centered on Ruminococcaceae and Pseudomonadaceae. NIs are common and associated with poor outcomes in cirrhosis. Admission gut microbiota in patients with NIs showed higher pathobionts and lower commensal microbiota. Microbial-metabolomic correlations were more complex, dense, and homogeneous among those who developed NIs, indicating greater linkage strength. Serum metabolites and gut microbiota on admission are associated with NI development in cirrhosis.

Inflammatory Markers Related to Innate and Adaptive Immunity in Atherosclerosis: Implications for Disease Prediction and Prospective Therapeutics

Several lines of evidence have linked a dysregulated inflammatory setting to the pathogenesis of atherosclerosis, which is a form of chronic vascular inflammation. Various inflammatory biomarkers have been associated with inflammation and are recognized as potential tools to monitor the progression of atherosclerosis. A well-studied inflammatory marker in the context of cardiovascular diseases is C-reactive protein (CRP) or, more accurately, highly sensitive-CRP (hs-CRP), which has been established as an inflammatory biomarker for atherosclerotic events. In addition, a growing body of investigations has attempted to disclose the potential of inflammatory cytokines, enzymes, and genetic polymorphisms related to innate and adaptive immunity as biomarkers for predicting the development of atherosclerosis. In this review article, we clarify both traditional and novel inflammatory biomarkers related to components of the innate and adaptive immune system that may mirror the progression or phases of atherosclerotic inflammation/lesions. Furthermore, the contribution of the inflammatory biomarkers in developing potential therapeutics against atherosclerotic treatment will be discussed.

Nobiletin Regulates ROS/ADMA/DDAHII/eNOS/NO Pathway and Alleviates Vascular Endothelium Injury by Iron Overload

Iron overload is harmful to health and associates with intracellular excessive reactive oxygen species (ROS) generation. Nobiletin (Nob) is known to be antioxidant and anti-inflammatory. However, whether Nob can protect endothelial cells against iron overload has not been studied, and the specific mechanism has not yet been elucidated. In this study, we have identified the protective effects of Nob, and its underlying molecular mechanism in human umbilical vein endothelial cells (HUVECs) suffered from iron overload via ROS/ADMA/DDAHII/eNOS/NO pathway. We found that compared with 50 μM iron dextran treatment, co-treatment with 20 μM Nob increased cell viability and decreased lactate dehydrogenase activity. Besides, Nob could upregulate DDAHII expression and activity, promote eNOS phosphorylation to produce more NO, reduce ADMA content, and therefore increase superoxide dismutase, catalase, and glutathione peroxidase activities, and decrease malondialdehyde level and ROS generation. Nob also inhibited mitochondrial permeability transition pore (mPTP) openness and cleaved caspase-3 expression, and decreased apoptosis induced by iron overload. These results were consistent when Nob was replaced by the positive control reagents L-arginine (a competitive substrate of ADMA), cyclosporin A (an mPTP closing agent), or edaravone (a free radical scavenger). The addition of pAD/DDAHII-shRNA adenovirus reversed the above effects of Nob. These data suggested that the protective mechanism of Nob was to inhibit ROS burst, upregulate DDAHII expression and activity, promote eNOS phosphorylation, produce NO, reduce ADMA content, and ultimately alleviate iron overload damage in vascular endothelium.

Increased Serum Levels of Asymmetric Dimethylarginine and Symmetric Dimethylarginine and Decreased Levels of Arginine in Sudanese Patients with Essential Hypertension

INTRODUCTION

Essential hypertension (EH) is a disease caused by various environmental and genetic factors. Nitric oxide (NO) is important for the functional integrity of the endothelium. It is produced in endothelial cells by endothelial NO synthase (eNOS) that mediates the conversion of the amino acid arginine into NO and citrulline. Asymmetric dimethylarginine (ADMA) acts as an inhibitor of eNOS. In contrast, symmetric dimethylarginine (SDMA) has no direct effect on eNOS but plays an important role competing with arginine for transport across the amino acid transporter. ADMA and SDMA have been found to play a central role in the development of cardiovascular diseases. Serum ADMA levels may serve as a future diagnostic marker and a target of therapy in hypertensive patients in the Sudanese population. This study aimed to investigate the relation between serum arginine, ADMA, and SDMA levels with EH in the Sudanese population.

METHODS

Patients (n = 260) with established hypertension and controls (n = 144) with normal blood pressure were included in this case-control study. Serum blood samples were analyzed for arginine, ADMA, and SDMA, using high-performance liquid chromatography-tandem mass spectrometry. Other laboratory data were measured using routine methods. Mann-Whitney's U test and χ2 tests were used for continuous and categorical data, respectively. A multivariate logistic regression analysis was conducted to investigate the independent effect of multiple variables on the development of hypertension.

RESULTS

Serum arginine levels were significantly lower in the patient group than in the control group (p < 0.001). ADMA and SDMA levels were significantly higher in the patient group than the control group (p < 0.001, p = 0.001, respectively). Multivariate logistic regression analysis showed that only older age, being a male, and arginine levels are independent factors controlling the development of hypertension (p < 0.001, p < 0.001, and p = 0.046, respectively). ADMA and SDMA levels were not independent factors for the development of hypertension.

CONCLUSIONS

This study demonstrated increased serum levels of ADMA and SDMA and decreased arginine levels in Sudanese patients with EH. Lowering serum ADMA levels or increasing the arginine levels might be a novel therapeutic target in these individuals.

Kaempferol protects mitochondria and alleviates damages against endotheliotoxicity induced by doxorubicin

Kaempferol (Kae), a flavonoid, has been found in fruits and other vegetables, possesses many biological activities. 14-3-3 protein exerts protection on various types of injured tissues and cells. Doxorubicin (Dox) causes excessive reactive oxygen species (ROS) generation, which induces endotheliotoxicity and cardiotoxicity. We hypothesized that Kae could protect vascular endothelium by regulating 14-3-3γ or related pathways against Dox toxicity. HUVECs were established Dox-toxic injury models. Kae's effects were assessed with many physiological, enzymatic, cellular, and molecular biological indexes. Our results showed that Dox-induced damage in HUVECs were reduced through Kae to promote the expression of total protein 14-3-3γ and mitochondrial Bcl-2, phosphorylate Bad, increase cell viability, NO content, DDAHⅡactivity, p-eNOS/eNOS ratio, and MMP levels, maintained NAD⁺/NADH and GSH/GSSG balance, and decrease LDH and caspase-3 activities, ADMA content, ROS generation, mPTP openness, and apoptosis. Kae's effects were abolished with pAD/14-3-3γ-shRNA downregulating 14-3-3γ expression, or ABT-737 inhibiting Bcl-2 activity. This study demonstrated that Kae protected the vascular endothelium against Dox-induced damage by regulating 14-3-3γ and ADMA/DDAHⅡ/eNOS/NO pathway, inhibiting oxidative stress, and improving mitochondrial function.

Tetramethylpyrazine alleviates iron overload damage in vascular endothelium via upregulating DDAHII expression

Iron overload causes vascular endothelium damage. It has been thought to relate excessive reactive oxygen species (ROS) generation. Tetramethylpyrazine (TMP), an active ingredient of Ligusticum chuanxiong Hort, protects various cells by inhibiting oxidative stress and cascade reaction of apoptosis. However, whether TMP can increase DDAHII activity and expression against endothelial cell damage induced by iron overload, and the protective mechanism has not been elucidated. In this study, 50 μM iron dextran and 25 μM TMP were used to co-treat HUVECs for 48 h. TMP could increase cell viability and decrease LDH activity, enhance DDAHII expression and activity, p-eNOS/eNOS ratio, NO content, and reduce ADMA level. TMP also showed a strong antioxidant activity with inhibited ROS generation and oxidative stress. Moreover, TMP attenuated mitochondrial membrane potential loss, inhibited mitochondrial permeability transition pore openness, and decreased apoptosis induced by iron overload. While mentioned above, the protective effects of TMP were abolished with the addition of pAD/DDAHII-shRNA. The effects of TMP against iron overload were similar to the positive control groups, L-arginine, a competitive substrate of ADMA, or edaravone, free radical scavenger. These results signify that TMP alleviated iron overload damage in vascular endothelium via ROS/ADMA/ DDAHII/eNOS/NO pathway.

Quercetin protects the vascular endothelium against iron overload damages via ROS/ADMA/DDAHⅡ/eNOS/NO pathway

The aberrant accumulation of iron causes vascular endothelium damage, which is thought to be associated with excess reactive oxygen species (ROS) generation. Quercetin (Que), as a flavonoid, has a certain ability to scavenge free radicals. Therefore, we aimed to explore the protective mechanism of Que on iron overload induced HUVECs injury focused on ROS/ADMA/DDAHⅡ/eNOS/NO pathway. In this study, HUVECs was treated with 50 μM iron dextran and 20 μM Que for 48 h. We found that Que attenuated the damages induced by iron, as evidenced by decreased ROS generation, increased DDAHⅡexpression and activity, reduced ADMA level, increased NO content and p-eNOS/eNOS ratio, and eventually caused a decrease in apoptosis. After addition of pAD/DDAHⅡ-shRNA, the effects of Que mentioned above were reversed. Meanwhile, iron overload induced mitochondrial oxidative stress, reduced mitochondrial membrane potential and increased mitochondrial permeability transition pores (mPTP) opening, which were also partially alleviated by Que. In addition, L-arginine (L-Arg), a ADMA competition substrate, ciclosporin A (CsA), a mPTP blocking agent, and edaravone (Eda), a free radical scavenger, were used as positive control reagents. The effects of Que were similar to that of L-Arg, CsA and Eda treatment. These results illustrated that Que could attenuate iron overload induced HUVECs mitochondrial dysfunction via ROS/ADMA/DDAHⅡ/eNOS/NO pathway.

Iron Overload Damages the Endothelial Mitochondria via the ROS/ADMA/DDAHII/eNOS/NO Pathway

It has been recognized that iron overload may harm the body's health. Vascular endothelial cells (VECs) are one of the main targets of iron overload injury, and the mechanism involved was thought to be related to the excessive generation of reactive oxygen species (ROS). However, the subcellular and temporal characteristics of ROS generation, potential downstream mechanisms, and target organelles in VECs injured by iron overload have not been expounded yet. In this study, we elucidated the abovementioned issues through both in vivo and in vitro experiments. Mice were fed pellet diets that were supplemented with iron for 4 consecutive months. Results showed that the thoracic aortic strips' endothelium-dependent dilation was significantly impaired and associated with inflammatory changes, noticeable under brown TUNEL-positive staining in microscopy analysis. In addition, the serum content of asymmetric dimethylarginine (ADMA) increased, whereas nitric oxide (NO) levels decreased. Furthermore, the dimethylarginine dimethylaminohydrolase II (DDAHII) expression and activity, as well as the phosphorylation of endothelial nitric oxide synthase (eNOS) in aortic tissue, were inhibited. Human umbilical vein endothelial cells were treated with 50 μM iron dextran for 48 hours, after which the cell viability, NO content, DDAHII expression and activity, and phosphorylation of eNOS decreased and lactate dehydrogenase and caspase-3 activity, ADMA content, and apoptotic cells significantly increased. After the addition of L-arginine (L-Arg) or pAD/DDAHII, the abovementioned changes were reversed. By dynamically detecting the changes of ROS generation in the cytoplasm and mitochondria and interfering with different aspects of signaling pathways, we have confirmed for the first time that excessive ROS originates from the cytoplasm and activates the ROS-induced ROS release (RIRR) mechanism, leading to mitochondrial dysfunction. Together, our data suggested that excessive free iron ions produced excess ROS in the cytoplasm. Thus, excess ROS create one vicious circle by activating the ADMA/eNOS/DDAHII/NO pathway and another vicious circle by activation of the RIRR mechanism, which, when combined, induce a ROS burst, resulting in mitochondrial dysfunction and damaged VECs.

The effect of melatonin on endothelial dysfunction in patients after acute coronary syndrome: The MEFACS randomized clinical trial

Endothelial dysfunction (ED) precedes acute coronary syndrome. Oxidative stress results in ED but is reversible. Melatonin is aside from being a circadian hormone, also an antioxidant. The aim of this study was to investigate whether 25 mg melatonin administered for twelve weeks following acute coronary syndrome (ACS) could improve ED. In this placebo-controlled randomized trial, ED was measured as reactive hyperemia index (RHI) at baseline, day 14, and day 84. The effect was assessed using a generalized estimating equation adjusted for the baseline RHI. As secondary outcome, the concentrations of three biomarkers were measured: l-arginine, asymmetric dimethylarginine, and uric acid. Thirty-one patients were included in the study. The intention-to-treat analysis of the primary outcome had 26 patients due to missing data. The estimated marginal mean difference in RHI at day 14 and day 84 between the groups was 0.15 (95% CI: 0.29-0.01, P = .039) in favor of the placebo group. No significant differences in the biomarker concentrations were found. Melatonin treatment after ACS did not improve but may have aggravated ED. The significant difference between groups was in favor of placebo, but this might be due to the effect of missing data or uneven distribution of comorbidities.

The impact of the combination of kidney and physical function on cognitive decline over 2 years in older adults with pre-dialysis chronic kidney disease

BACKGROUND

No longitudinal study has investigated the impact of combination of kidney function (KF) and physical function (PF) on cognitive decline in these patients.

METHODS

We conducted a 2-year prospective cohort study enrolling 131 patients ≥ 65 years with pre-dialysis chronic kidney disease (CKD). We assessed cognitive function with the Japanese version of the Montreal Cognitive Assessment (MoCA-J). We calculated %MoCA-J based on the rate of change between baseline and follow-up MoCA-J scores, and defined cognitive decline over 2 years as a %MoCA-J of less than the first quartile value. We defined eGFR ≥ 30 as mild-to-moderate and eGFR < 30 mL/min per 1.73 m² as severe. In addition, low PF was defined as low handgrip strength (< 26 for men and < 18 kgf for women) and/or low gait speed (< 0.8 m/s). Patients were classified into four groups: group 1, patients with mild-to-moderate impairment in KF and high PF; group 2, with mild-to-moderate impairment in KF and low PF; group 3, with severe impairment in KF and high PF; and group 4, with severe impairment in KF and low PF.

RESULTS

Eighty-four patients completed follow-up assessment. Multivariate logistic regression analysis showed that the combination of severe impairment in KF and low PF was significantly associated with cognitive decline (odds ratio 5.73). However, no significant cognitive decline was observed in patients with either severe impairment in KF or low PF alone.

CONCLUSIONS

We may need to focus on maintaining PF in older patients with advanced CKD may help to prevent cognitive decline.

Ticagrelor mitigates ischaemia-reperfusion induced vascular endothelial dysfunction in healthy young males - a randomized, single-blinded study

AIMS

Animal data suggest that ticagrelor but not clopidogrel protects against tissue injury. It is unclear if this effect of ticagrelor is also detectable in humans. We studied the effect of ticagrelor and clopidogrel at standard clinical doses on endothelial dysfunction in an experimental model of forearm vascular ischaemia-reperfusion (IR) injury.

METHODS

In a randomized, single-blinded trial, 24 subjects underwent forearm blood flow (FBF) measurements in response to the endothelium-dependent vasodilator acetylcholine (ACh) and to glyceryltrinitrate (GTN; endothelium-independent) before and after a 20 min forearm ischaemia. FBF reactivity was assessed after an oral loading dose of ticagrelor or clopidogrel and after 14 days of regular intake of maintenance doses of the study medicines. In addition, the effect on platelet inhibition was evaluated using multiple electrode aggregometry.

RESULTS

ACh-induced vasodilation was impaired during reperfusion and not completely normalized by acute or chronic treatment with ticagrelor or clopidogrel (post- vs. pre-ischaemia). However, ticagrelor mitigated endothelial dysfunction compared to clopidogrel after loading (FBF ACh_AUC ratio post- vs. pre-ischaemia: 0.83 [0.70; 0.96] vs. 0.64 [0.56; 0.72]; P = 0.024) and after chronic administration (FBF ACh_AUC ratio: 0.86 [0.71; 1.00] vs. 0.66 [0.55; 0.77]; P = 0.027). As expected, GTN-induced vasodilation was not affected by ischaemia. Ticagrelor or clopidogrel treatment inhibited platelet activation to a similar degree.

CONCLUSION

Our data indicate that ticagrelor treatment exerts a greater vascular salutary effect than clopidogrel during reperfusion after an acute vascular occlusion. IR-induced vascular injury cannot be prevented completely by administration of these antiplatelet agents at standard clinical doses.

Red blood cell nitric oxide synthase modulates red blood cell deformability in sickle cell anemia

Sickle cell anemia (SCA) is an inherited red blood cells (RBC) disorder characterized by significantly decreased RBC deformability. The present study aimed to assess whether modulation of RBC Nitric Oxide Synthase (RBC-NOS) activation could affect RBC deformability in SCA.Blood of twenty-five SCA patients was treated for 1 hour at 37°C with Phosphate Buffered Saline (PBS) or PBS containing 1% of Dimethylsulfoxyde as control, L-arginine or N(5)-(1-Iminoethyl)-L-ornithine (L-NIO) to directly stimulate or inhibit RBC-NOS, insulin or wortmannin to indirectly stimulate or inhibit RBC-NOS through their effects on the PI3 Kinase/Akt pathway, and sodium nitroprusside (SNP) and 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) as NO donor and NO scavenger, respectively. RBC deformability was measured by ektacytometry at 3 Pa.RBC deformability significantly increased after insulin treatment and significantly decreased after L-NIO and wortmannin incubation. The other conditions did not affect deformability. Significantly increased nitrotyrosine levels, a marker of enhanced free radical generation, were detected by immunohistochemistry in SNP and insulin treated samples.These data suggest that RBC deformability of SCA can be modulated by RBC-NOS activity but also that oxidative stress may impair effectiveness of RBC-NOS produced NO.

Soluble Endoglin Level Increase Occurs Prior to Development of Subclinical Structural Vascular Alterations in Diabetic Adolescents

OBJECTIVE

Soluble endoglin (S-endoglin) has been implicated as a potential marker of endothelial dysfunction (ED) and was reported to be elevated in diabetic adults, correlating with the severity of diabetic vasculopathy. However, circulating S-endoglin and its association with other markers of ED have not been formerly analyzed in the first decade of diabetes onset in adolescents with type 1 diabetes mellitus (T1DM).

METHODS

Fifty-eight adolescents with moderately/poorly controlled T1DM were included in this study and twenty-nine healthy adolescents served as controls. The diabetic group was divided into two groups based on the presence of microalbuminuria, as the microalbuminuria group (n=15) and the normoalbuminuria group (n=43). Functional vascular alterations were evaluated by measuring serum S-endoglin and plasma nitric oxide (NO) concentrations, the flow-mediated dilatation (FMD) of the brachial artery. Carotid intima media thickness (CIMT) was measured for evaluation of structural vascular alterations.

RESULTS

The S-endoglin and NO levels of both microalbuminuria and normoalbuminuria groups were higher than those of the control group (for S-endoglin, p=0.047 and p<0.001; for NO, p=0.004 and p=0.006, respectively). The FMD percent was lower in the microalbuminuria group compared to the normoalbuminuria and control groups (p=0.036 and p=0.020, respectively). There were negative correlations between S-endoglin concentration and FMD percent (r=-0.213, p=0.051) and between serum S-endoglin concentration and albumin excretion rate (r=-0.361, p=0.005). No significant differences were found in CIMT among any of the groups (p=0.443).

CONCLUSION

In adolescents with T1DM, S-endoglin concentrations might increase in parallel to the deterioration in endothelial function before subclinical structural vascular alterations become evident.

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.

Association between hypertriglyceridemia and protein oxidation and proinflammatory markers in normocholesterolemic and hypercholesterolemic individuals

BACKGROUND

Although hypercholesterolemia is a well-established risk factor for coronary heart disease, evidence suggests that increased triglyceride (TG) concentrations are also an independent risk factor. TG concentrations >150mg/dl are observed nearly twice as often in subjects with atherosclerosis. We assessed the association between hypertriglyceridemia and protein oxidation and proinflammatory markers in normocholesterolemic and hypercholesterolemic individuals.

METHODS

We included 127 volunteers enrolled in Cruz Alta, RS, Brazil. The patients were stratified based on total cholesterol and TG concentrations for analysis of associations with inflammation (high-sensitivity C-reactive protein - hs-CRP), endothelial dysfunction (nitric oxide - NOx) and oxidative stress (advanced oxidation protein products - AOPPs; ischemia-modified albumin - IMA). Correlations between variables were determined and multiple regression analysis was employed to investigate whether some variables correlate with TG concentrations.

RESULTS

Hypertriglyceridemia was related to oxidative stress and proinflammatory markers in individuals independent of total cholesterol concentrations. Moreover, the results indicate a stronger association of tested biomarkers with TG concentrations than with total cholesterol. The results indicate a positive correlation between oxidative stress and TG concentrations in the sera of hypercholesterolemia subjects. AOPPs and IMA concentrations were associated with the presence of hypertriglyceridemia in a manner that was independent of age, gender, hypertension and diabetes mellitus disease, smoking habits, sedentary lifestyle, BMI, waist circumference, LDL, HDL and total cholesterol concentrations.

CONCLUSIONS

We speculate that TG concentrations can reflect the enhancement of protein oxidation and proinflammation.

Left ventricular diastolic dysfunction and plasma asymmetric dimethylarginine concentration in persons with essential hypertension

INTRODUCTION

The study aimed to evaluate the relationship between plasma asymmetric dimethylarginine (ADMA) concentration and development of left ventricular diastolic dysfunction (LVDD) in patients with essential hypertension (EH). Moreover, an attempt was made to define independent risk factors of LVDD in patients with EH.

MATERIAL AND METHODS

A group of 106 individuals with EH was obtained (mean age: 47.18 ±11.76 years). Two groups of patients were distinguished: group I - individuals with EH with LVDD (n = 57); group II - persons with EH without LVDD (n = 49). Echocardiographic examination was conducted by the transthoracic technique. High-performance liquid chromatography was used to measure dimethylarginine concentrations.

RESULTS

In the group suffering from EH with LVDD, mean ADMA concentration was significantly higher and the ratio of arginine to ADMA was significantly lower than in patients with EH without LVDD. No significant differences were detected between mean concentrations of plasma symmetric dimethylarginine concentration (SDMA) and arginine or in arginine/SDMA ratios in the studied groups. Independent factors of LVDD risk in the study group included higher plasma ADMA concentration, higher serum low-density lipoprotein (LDL) concentration, higher values of body mass index (BMI), higher values of left ventricular mass index (LVMI) and higher values of mean blood pressure (mBP) (ORADMA = 1.731; ORLDL = 1.188; ORBMI = 1.056; ORLVMI = 1.062; ORmBP = 1.014; p < 0.05).

CONCLUSIONS

The results of this study showed that ADMA concentration may be of prognostic value in relation to manifestation of LVDD in patients with EH.

Plasma levels of dimethylarginines in preterm very low birth weight neonates: its relation with perinatal factors and short-term outcome

Endogenously produced inhibitors of nitric oxide (NO) synthase, in particular asymmetric dimethylarginine (ADMA), are currently considered of importance in various disease states characterized by reduced NO availability. We investigated the association between plasma levels of ADMA, symmetric dimethylarginine (SDMA), l-arginine, and citrulline and perinatal factors and outcome in 130 preterm (gestational age ≤30 weeks) very low birth weight (VLBW, <1500 g) infants. Plasma samples were collected 6–12 h after birth. We did not find significant correlations between ADMA, SDMA, l-arginine, and citrulline levels and gestational age or birth weight. However, the arginine:ADMA ratio (AAR, a better indicator of NO availability than either arginine or ADMA separately) was positively correlated with gestational age. ADMA and arginine levels were not significantly different between males and females but males showed a negative correlation between ADMA levels and gestational age. Perinatal factors such as preeclampsia, chrorioamnionitis, prolonged rupture of membranes, or form of delivery did not significantly alter dimethylarginine levels or AAR. In contrast, the AAR was significantly reduced in the infants with respiratory distress, mechanical ventilation, and systemic hypotension Therefore, our data suggest that altered NO availability may play a role in the respiratory and cardiovascular adaptation in preterm VLBW infants.

Effect of a high dose of vitamin D on a rabbit model of atherosclerosis

Multifactorial factors have been involved in atherosclerosis. An association has been shown between osteoporosis and carotid atherosclerosis. This work evaluates the effect of vitamin D on regression of atherosclerosis. Forty-eight male rabbits were divided into: Group Ia: [Standard diet + saline for 4 weeks]; Group I b: [Standard diet + a high dose of vitamin D3 daily for 4 weeks]; Group IIa: [Cholesterol–enriched diet for 4 weeks]; Group IIb: [Cholesterol–enriched diet + a single high dose of vit D3, daily for 4 weeks. At the end of 4 weeks, the rabbits were sacrificed for assay in serum lipid profile, C reactive protein (CRP), vitamin D3 metabolite, calcium, soluble adhesion molecules (sVCAM and sICAM) and nitrite (NO) and malondialdehyde (MDA) released from isolated aortic rings. Results showed that vitamin D produced a significant reduction in the sera of lipid profile, CRP, and adhesion molecules, associated with a non-significant change in serum calcium and a significant increase in the body level of vitamin D3. Addition of vitamin D to the incubated aortic rings of the atherosclerotic rabbits resulted in a significant increase in NO and decrease in MDA release. It could be concluded that vitamin D has anti-atherosclerotic effects, and may exert these effects by inhibiting lipid peroxidation and stimulation of nitric oxide, resulting in attenuation of the inflammatory atherosclerotic process.

Arterial Stiffness: A Nexus between Cardiac and Renal Disease

Vascular disease is the leading cause of morbidity and mortality in the Western world, and vascular function is determined by structural and functional properties of the arterial vascular wall. Cardiorenal metabolic syndrome such as obesity, diabetes, hypertension, kidney disease, and aging are conditions that predispose to arterial stiffening, which is a pathological alteration of the vascular wall and ultimately results in target organ damage in heart and kidney. In this review, we provide new insights on the interactions between arterial stiffness, vascular resistance and pulse wave velocity as well as final end-organ damage in heart and kidney. Better understanding of the mechanisms of arterial functional and hemodynamic alteration may help in developing more refined therapeutic strategies aimed to reduce cardiovascular and chronic kidney diseases.

Effects of Campomanesia xanthocarpa on inflammatory processes, oxidative stress, endothelial dysfunction and lipid biomarkers in hypercholesterolemic individuals

In Brazil, the edible plant Campomanesia xanthocarpa Berg. (Myrtaceae), popularly known as "guavirova," has been studied in hypercholesterolemic individuals. The present work investigated the effects of C. xanthocarpa on inflammatory processes, oxidative stress, endothelial dysfunction and lipid biomarkers in hypercholesterolemic individuals. A total of 156 individuals were selected in a double-blind fashion and randomly divided into two groups in accordance with the intervals used in the criteria for hypercholesterolemia: individuals with total cholesterol (TC) levels between 200 and 240 mg/dL (undesirable level individuals - UL) and individuals with TC levels >240 mg/dL (hypercholesterolemic individuals - HL). Both groups had a control group (CG), which received placebo treatment, an encapsulated excipient group (lactose) and an experimental group that received 500 mg (EG 500), 750 mg (EG 750) or 1000 mg (EG 1000) of encapsulated C. xanthocarpa. The inflammatory processes (high-sensitivity C-reactive protein - hs-CRP), oxidative stress (advanced oxidation protein products-AOPPs; ischemia-modified albumin-IMA), endothelial dysfunction (nitric oxide - NOx) and biochemical (TC, triglycerides, high-density lipoprotein - HDL, low-density lipoproteins - LDL, and very low-density lipoprotein - VLDL) parameters were measured before and 90 days after the initiation of treatment. A significant decrease in TC and LDL levels was observed in HL individuals from the EG 500 group (reduction of 29 ± 3% and 41 ± 5% to levels before treatment) compared to the CG group individuals. A significant reduction in oxidative stress and inflammatory process components (reduction of 52 ± 11% in AOPPs, 32 ± 10% in IMA and 57 ± 7% in hs-CRP) and a significant increase in NOx (increase of 84 ± 27%) was observed in HL individuals in the EG 1000 group when compared to the CG group individuals. Treatment with encapsulated C. xanthocarpa reduced blood TC and LDL levels in hypercholesterolemic individuals. In addition to its effect on cholesterol levels, this plant reduced oxidative stress in hypercholesterolemic individuals and improved the levels of NOx.

Effects of prostacyclin on the early inflammatory response in patients with traumatic brain injury-a randomised clinical study

OBJECTIVE AND DESIGN

A prospective, randomised, double-blinded, clinical trial was performed at a level 1 trauma centre to determine if a prostacyclin analogue, epoprostenol (Flolan®), could attenuate systemic inflammatory response in patients with severe traumatic brain injury (TBI).

SUBJECTS

46 patients with severe TBI, randomised to epoprostenol (n = 23) or placebo (n = 23).

TREATMENT

Epoprostenol, 0.5 ng · kg(-1) · min(-1), or placebo (saline) was given intravenously for 72 hours and then tapered off over the next 24 hours.

METHODS

Interleukin-6 (IL-6), interleukin-8 (IL-8), soluble intracellular adhesion molecule-1 (sICAM-1), C-reactive protein (CRP), and asymmetric dimethylarginine (ADMA) levels were measured over five days. Measurements were made at 24 h intervals ≤24 h after TBI to 97-120 h after TBI.

RESULTS

A significantly lower CRP level was detected in the epoprostenol group compared to the placebo group within 73-96 h (p = 0.04) and within 97-120 h (p = 0.008) after trauma. IL-6 within 73-96 h after TBI was significantly lower in the epoprostenol group compared to the placebo group (p = 0.04). ADMA was significantly increased within 49-72 h and remained elevated, but there was no effect of epoprostenol on ADMA levels. No significant differences between the epoprostenol and placebo groups were detected for IL-8 or sICAM-1.

CONCLUSIONS

Administration of the prostacyclin analogue epoprostenol significantly decreased CRP and, to some extent, IL-6 levels in patients with severe TBI compared to placebo. These findings indicate an interesting option for treatment of TBI and warrants future larger studies.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier, NCT01363583.

Effect of systemic high dose vitamin C therapy on forearm blood flow reactivity during endotoxemia in healthy human subjects

OBJECTIVE

Acute inflammation induced by administration of Escherichia coli lipopolysaccharide endotoxin (LPS) reduces plasma concentrations of vitamin C and impairs vascular endothelium-derived nitric oxide (NO) bioactivity. We tested the hypothesis that systemically administered high dose vitamin C restores the endogenous anti-oxidant potential and improves NO-dependent vasodilatation in the forearm vasculature.

DESIGN & SETTING

36 male subjects were enrolled in this balanced, placebo controlled cross-over study. Forearm blood flow (FBF) reactivity to acetylcholine (ACh) and glyceryl-trinitrate (GTN), a sensitive test for endothelial function, was assessed at baseline and 4h after LPS-administration (20 IU/kg i.v). The effect of two different doses of intravenous vitamin C (Vitamin C-Injektopas®), 320 mg/kg and 480 mg/kg over 2h, or placebo on forearm vascular function was studied after LPS.

MAIN RESULTS

LPS caused transient flu-like symptoms, decreased plasma vitamin C concentrations and reduced the ACh-dependent increase in FBF by up to 76%. Vitamin C at a mean plasma concentration of 3.2 or 4.9 mmol/L restored the response to ACh compared to baseline.

CONCLUSION

High dose systemic vitamin C recovers LPS-induced endothelium-dependent vasodilation in the forearm resistance vasculature. This provides a rationale for a further clinical study of the systemic vitamin C effect under inflammatory conditions.

Apelin-13 deteriorates hypertension in rats after damage of the vascular endothelium by ADMA

Asymmetric dimethylarginine (ADMA) is a risk factor for endothelial dysfunction. The polypeptide apelin has biphasic effects on blood vessels in vivo and in vitro. We investigated the effect of apelin-13 on ADMA-damaged vessels. Rats were divided among ADMA-treated and control groups, which were treated with ADMA (10 mg·(kg body mass)−1·day−1) or saline, respectively, for 4 weeks. Systolic blood pressure (SBP) was measured before and after the injection of apelin-13. The ultrastructure of endothelial cells in caudal arteries was examined using transmission electron microscopy. The reactivities of isolated caudal artery rings were observed after exposure to apelin-13, and myosin light chain (MLC) phosphorylation was assessed by immunohistochemistry in rings treated with or without apelin-13. ADMA induced hypertension and endothelial dysfunction. After injection of apelin-13, SBP declined in the control group but was elevated in the ADMA-treated group. In vitro, apelin-13 caused relaxation in rings in the control group, but it contracted rings in the ADMA-treated group. Apelin-13 promoted MLC phosphorylation in vascular smooth muscle cells (VSMCs) in the ADMA group. These results indicate that apelin-13 might pass through ADMA-damaged endothelium and act on VSMCs to increase MLC phosphorylation, thus contributing to vasoconstriction and exacerbating hypertension.

FXR agonist INT-747 upregulates DDAH expression and enhances insulin sensitivity in high-salt fed Dahl rats

Aims

Genetic and pharmacological studies have shown that impairment of the nitric oxide (NO) synthase (NOS) pathway is associated with hypertension and insulin-resistance (IR). In addition, inhibition of NOS by the endogenous inhibitor, asymmetric dimethylarginine (ADMA), may also result in hypertension and IR. On the other hand, overexpression of dimethylarginine dimethylaminohydrolase (DDAH), an enzyme that metabolizes ADMA, in mice is associated with lower ADMA, increased NO and enhanced insulin sensitivity. Since DDAH carries a farnesoid X receptor (FXR)-responsive element, we aimed to upregulate its expression by an FXR-agonist, INT-747, and evaluate its effect on blood pressure and insulin sensitivity.

Methods and Results

In this study, we evaluated the in vivo effect of INT-747 on tissue DDAH expression and insulin sensitivity in the Dahl rat model of salt-sensitive hypertension and IR (Dahl-SS). Our data indicates that high salt (HS) diet significantly increased systemic blood pressure. In addition, HS diet downregulated tissue DDAH expression while INT-747 protected the loss in DDAH expression and enhanced insulin sensitivity compared to vehicle controls.

Conclusion

Our study may provide the basis for a new therapeutic approach for IR by modulating DDAH expression and/or activity using small molecules.

Assessment of atherosclerosis risk due to the homocysteine-asymmetric dimethylarginine-nitric oxide cascade in children taking antiepileptic drugs

PURPOSE

The aim of this study was to assess the atherogenicity risk of antiepileptics in children by investigating the cascade, "hyperhomocysteinemia (HHcy)→asymmetric dimethylarginine (ADMA) increase→nitric oxide (NO) decrease", which is thought to contribute to the developmental process of atherosclerosis.

METHODS

The participants included 53 epilepsy patients who received either valproic acid (VPA, n=26) or oxcarbazepine (OXC, n=27). Twenty-four healthy sex- and age-matched children served as controls. Fasting plasma total homocysteine (tHcy), ADMA and NO levels were measured.

RESULTS

The differences in Hcy, ADMA, NO, vitamin B(12) and folate levels between VPA, OXC and control groups were all insignificant (p>0.05 for all). In the patient group (VPA and OXC groups), 22.6% of the children (12/53) had tHcy levels above the normal cutoff (13.1μmol/l) for children and 17% of the children (9/53) had tHcy levels of greater than 15μmol/l which is accepted as the critical value for an increased atherosclerosis risk (p<0.05 for both). The difference in rate of HHcy between VPA and OXC groups was statistically insignificant (p>0.05, for both cut off levels of HHCy). There was a positive correlation of tHcy levels and antiepileptic drug treatment duration in the patient group (r=+0.276, p<0.05).

CONCLUSION

HHcy may develop in patients using OXC. Contrary to some previous publications, our data do not suggest that OXC is safer than VPA in terms of HHcy risk. Further prospective, large scale and longer term studies investigating all suggested pathways responsible for development of atherosclerosis due to HHcy should be conducted to define the exact mechanism responsible for AEDs related atherosclerosis.

Elevated homocysteine and asymmetric dimethyl arginine levels in pulmonary hypertension associated with congenital heart disease

Pulmonary arterial hypertension (PAH) is a major cause of morbidity and mortality among patients with congenital heart disease (CHD). This study was designed to determine biomarker levels in patients with PAH associated with CHD (PAH-CHD) and CHD patients without PAH and to investigate the relationship of these potential biomarkers with hemodynamic findings. In this prospective single-center study, patients with CHD were analyzed according to the presence or absence of PAH and compared with healthy control subjects. Cardiac catheterization and echocardiographs were performed. Plasma homocysteine, asymmetric dimethyl arginine (ADMA), and nitric oxide (NO) levels were determined by enzyme-linked immunosorbent assay. Homocysteine and ADMA levels were higher in the PAH-CHD group (n = 30) than among CHD patients with left-to-right shunting but no PAH (n = 20; P < 0.001) and healthy control subjects (n = 20; P < 0.001). There was no difference in NO levels. Cyanotic PAH-CHD patients had significantly higher homocysteine than acyanotic patients in the same group. No correlation was shown between echocardiographic/hemodynamic parameters and homocysteine, ADMA, and NO levels. Homocysteine and ADMA levels are increased in patients with PAH-CHD. These parameters have the potential to be used as biomarkers in the diagnosis and follow-up evaluation of patients with PAH-CHD. However, large, multicentered prospective studies are required to facilitate routine use of these biologic markers in the clinical setting.

Human obesity and endothelium-dependent responsiveness

Obesity is an ongoing worldwide epidemic. Besides being a medical condition in itself, obesity dramatically increases the risk of development of metabolic and cardiovascular disease. This risk appears to stem from multiple abnormalities in adipose tissue function leading to a chronic inflammatory state and to dysregulation of the endocrine and paracrine actions of adipocyte-derived factors. These, in turn, disrupt vascular homeostasis by causing an imbalance between the NO pathway and the endothelin 1 system, with impaired insulin-stimulated endothelium-dependent vasodilation. Importantly, emerging evidence suggests that the vascular dysfunction of obesity is not just limited to the endothelium, but also involves the other layers of the vessel wall. In particular, obesity-related changes in medial smooth muscle cells seem to disrupt the physiological facilitatory action of insulin on the responsiveness to vasodilator stimuli, whereas the adventitia and perivascular fat appear to be a source of pro-inflammatory and vasoactive factors that may contribute to endothelial and smooth muscle cell dysfunction, and to the pathogenesis of vascular disease. While obesity-induced vascular dysfunction appears to be reversible, at least in part, with weight control strategies, these have not proved sufficient to prevent the metabolic and cardiovascular complication of obesity on a large scale. While a number of currently available drugs have shown potentially beneficial vascular effects in patients with obesity and the metabolic syndrome, elucidation of the pathophysiological mechanisms underlying vascular damage in obese patients is necessary to identify additional pharmacologic targets to prevent the cardiovascular complications of obesity, and their human and economic costs.

LINKED ARTICLES

This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3.

[Methylarginies-induced endothelial dysfunction in chronic kidney disease]

Chronic kidney disease (CKD), defined as low glomerular filtration rates and/or the presence of albuminuria, is considered a risk factor for cardiovascular disease (CVD). In recent years, increasing emphasis has been placed on endothelial dysfunction as a key element underlying the relationship between CKD and CVD. Endothelial cells play a pivotal role in many aspects of vascular function by generating nitric oxide (NO). However, NO production is reduced in CKD patients, partially due to decreased endothelial NO production. One possible cause of NO deficiency is increased levels of endogenous NO synthase inhibitors, in particular asymmetric dimethylarginine (ADMA). Elevated plasma levels of ADMA are consequence of increased synthesis and reduced degradation. Accumulation of ADMA and inhibition of NO production might contribute to endothelial dysfunction, hypertension, initiation of atherosclerosis, and incidence of CVD. Clinical studies revealed that ADMA plasma concentration is increased in populations with renal disease, vascular diseases, and high cardiovascular risks. In this regard, ADMA is increasingly recognized as a biomarker of CKD and CVD. This review discusses ADMA-mediated endothelial dysfunction in CKD, especially focusing on the link between CKD and CVD.

Increased asymmetric dimethylarginine and nitric oxide levels in patients with migraine

Asymmetric dimethylarginine (ADMA) has been found as correlated with endothelial dysfunction and oxidative stress. There are few studies regarding ADMA and nitric oxide (NO) levels in patients with migraine and alterations of ADMA and NO levels during migraine attack are not well-known. Therefore, in present study, we aimed to measure NO and ADMA levels in patients with migraine and compare them with the control group to investigate the correlation between migraine, oxidative stress and endothelial dysfunction. The migraine group consisted of 59 patients, including 22 suffering from migraine with aura and 37 suffering from migraine without aura. The control group consisted of 31 healthy volunteers without headache. The patients in migraine group were divided into subgroups based on whether attack period was present or not and whether it was migraine with or without aura. Plasma ADMA levels were measured using an enzyme-linked immunosorbent assay method. Migraine patients had higher concentrations of NO (35.6±7.7, 31.0±6.2 μmol/L, respectively, p=0.005) and ADMA (0.409±0.028, 0.381±0.044 μmol/L, respectively, p = 0.001) levels when compared with the healthy controls. During migraine attack, NO and ADMA levels were found to be significantly higher in migraine group as compared to control group (respectively, p=0.015, p=0.014). Similarly, NO and ADMA levels in the patients with migraine in the interictal period were found to be significantly higher as compared to control group (p=0.011, p=0.003). In conclusion, higher ADMA and NO levels of patients with migraine supported that oxidative stress and endothelial dysfunction may have a role in migraine pathogenesis.

Biomarkers of inflammation and oxidative stress in atherosclerosis

Increasing evidence has highlighted the roles of oxidative stress and inflammation in the promotion of atherosclerotic cardiovascular disease. Recent pathological studies have elucidated specific mediators that appear to link these pathways to the progression and rupture of atherosclerotic plaque in the artery wall. The ability to measure levels of these mediators in the systemic circulation has provoked interest in their development as biomarkers for potential use in risk assessment and in evaluation of the response to the use of preventive therapies. The discovery of these pathological mediators and their potential translation to the clinical arena will be reviewed.

Asymmetric dimethylarginine concentrations are elevated in women with gestational diabetes

As shown in the previous studies, asymmetric dimethylarginine (ADMA) is related to endothelial dysfunction, whereas high-sensitive C-reactive protein (hCRP) is the marker of inflammation. In our study, we investigated ADMA, hCRP, and homocysteine concentrations in women with gestational diabetes mellitus (GDM) and normal glucose tolerance (NGT) during late pregnancy. Fifty-four women with GDM and 69 women with NGT between 32 and 39 weeks of gestation were included in this study. ADMA, hCRP, homocysteine, lipid parameters, glycated hemoglobin (HbA1c) levels, insulin, and homeostasis model assessment for insulin resistance (HOMA-IR) were measured. The plasma ADMA concentrations were significantly higher in GDM patients than in NGT subjects (P = 0.03) and the hCRP levels were also significantly increased in GDM group when compared with those in the NGT group (P = 0.008). However, plasma homocysteine levels did not differ between the groups (P = 0.4), while HOMA-IR, insulin, and triglyceride levels were higher in the GDM group than in the NGT group (P = 0.001, 0.002, and 0.02, respectively). The ADMA concentrations in the third trimester were positively correlated with the glucose levels the 50-g glucose challenge test (GCT) during 24-28 weeks in the whole group (r = 0.21, P = 0.02). Our results demonstrate that ADMA and hCRP are elevated in women with GDM during late pregnancy. Further studies are needed to clarify the significance and the underlying mechanisms of the elevated ADMA and hCRP levels in women with GDM.

Coronary endothelial function and vascular smooth muscle proliferation are programmed by early-gestation dexamethasone exposure in sheep

Exposure of the early-gestation ovine fetus to exogenous glucocorticoids induces changes in postnatal cardiovascular physiology. We sought to characterize coronary artery vascular function in this model by elucidating the contribution of nitric oxide and reactive oxygen species to altered coronary vascular reactivity and examining the proliferative potential of coronary artery vascular smooth muscle cells. Dexamethasone (dex, 0.28 mg x kg(-1) x day(-1) for 48 h) was administered to pregnant ewes at 27-28-day gestation (term 145 days). Coronary arteries were isolated from 1- to 2-wk-old dex-exposed offspring and aged-matched controls. Compared with controls, coronary arteries from dex-exposed lambs demonstrated enhanced vasoconstriction to endothelin-1 and ACh that was abolished by endothelial removal or preincubation with the nitric oxide synthase inhibitor L-NNA, membrane-permeable superoxide dismutase + catalase, or apamin + charybdotoxin, but not indomethacin. The rate of coronary vascular smooth muscle cell (VSMC) proliferation was also significantly greater in dex-exposed lambs. Protein levels of the proliferating cell nuclear antigen were increased and alpha-smooth muscle actin decreased in dex-exposed coronary VSMC, consistent with a proliferative state. Finally, expression of the NADPH oxidase Nox 4, but not Nox 1, mRNA was also decreased in coronary VSMC from dex-exposed lambs. These findings suggest an important interaction exists between early-gestation glucocorticoid exposure and reactive oxygen species that is associated with alterations in endothelial function and coronary VSMC proliferation. These changes in coronary physiology are consistent with those associated with the development of atherosclerosis and may provide an important link between an adverse intrauterine environment and increased risk for coronary artery disease.

The DDAH/ADMA pathway in the control of endothelial cell migration and angiogenesis

ADMA (asymmetric dimethylarginine) is a cardiovascular risk factor and an endogenous inhibitor of NOS (nitric oxide synthase). ADMA is metabolized by DDAHs (dimethylarginine dimethylaminohydrolases). ADMA levels are increased in cardiovascular disorders associated with abnormal angiogenesis but the mechanisms are poorly understood. Recent studies show that altering ADMA metabolism in vivo and in vitro modulates the activity of Rho GTPases, key regulators of actin dynamics, endothelial cell motility and angiogenesis. In the present review, we consider this and other NO-dependent and -independent molecular mechanisms by which the DDAH/ADMA pathway regulates angiogenesis.

High glucose enhances angiotensin-II-mediated peroxisome proliferation-activated receptor-gamma inactivation in human coronary artery endothelial cells

Activation of the renin-angiotensin system plays an important role in the pathogenesis of vascular complications of hyperglycemia. Clinical studies have demonstrated that hypoglycemic effects of peroxisome proliferation-activated receptor-gamma (PPAR-gamma) activation is potentially associated with a significant decrease of cardiovascular disease events in diabetes patients. We assessed the effect of high glucose on the angiotensin II (Ang II), which induced the inactivation of PPAR-gamma and its signal pathways in human coronary artery endothelial cells (HCAECs). The expression of angiotensin II receptor I (AT1R) protein was analyzed by Western blot and knocked down using siRNA. PPAR-gamma activation was examined using a luminometer and a Dual Luciferase Reporter Assay System. Adhesion molecule expressions of HCAECs were measured using ELISA. Both high glucose and Ang II induced a progressive increase in AT1R protein expression on the HCAECs. Troglitazone, a PPAR-gamma activator, significantly increased the transcription activity of PPAR-gamma in HCAECs in vitro. However, activation of PPAR-gamma was significantly inhibited by high glucose and Ang II stimulation. Furthermore, silencing of AT1R expression was able to inhibit the inactivation of PPAR-gamma induced by Ang II and high glucose. Meanwhile, expression of proinflammatory adhesion molecules was increased by high glucose and Ang II in HCAECs, which is blocked by troglitazone and silencing of AT1R expression. These data strongly suggest high glucose enhanced Ang-II-mediated peroxisome proliferation-activated receptor-gamma inactivation and expression of proinflammatory adhesion molecules in human coronary artery endothelial cells.