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We show here that increased oxidative stress is associated with migraine and contributes to migraine-related metabolic risk like nitrosative stress, an atherogenic lipid profile and hyperinsulinemia. Our data suggest that oxidative stress may represent a key event in the pathophysiology of migraine and a suitable therapeutic target.

Background-Statins may exert important pleiotropic effects, ie, improve endothelial function, independently of their impact on LDL cholesterol. In humans, however, pleiotropic effects of statins have never been unequivocally demonstrated because prolonged statin treatment always results in reduced LDL cholesterol levels. We therefore tested the hypothesis that similar reductions in LDL cholesterol with simvastatin and ezetimibe, a novel cholesterol absorption inhibitor, result in different effects on endothelial function. Methods and Results-Twenty patients with chronic heart failure were randomized to 4 weeks of simvastatin (10 mg/d) or ezetimibe (10 mg/d) treatment. Flow-dependent dilation (FDD) of the radial artery was determined by high-resolution ultrasound before and after intra-arterial vitamin C to determine the portion of FDD inhibited by radicals (⌬FDD-VC). Activity of extracellular superoxide dismutase, a major vascular antioxidant enzyme system, was determined after release from the endothelium by a heparin bolus injection. Endothelial progenitor cells were analyzed with an in vitro assay. Simvastatin and ezetimibe treatment reduced LDL cholesterol to a similar extent (15.6% versus 15.4%; PϭNS), whereas changes in mevalonate, the product of HMG-CoA-reductase, differed between groups (⌬mevalonate-simvastatin, Ϫ1.04Ϯ0.62 versus ⌬mevalonate-ezetimibe, 1.79Ϯ0.94 ng/mL; PϽ0.05 between groups). Importantly, FDD was markedly improved after simvastatin (10.5Ϯ0.6% versus 5.1Ϯ0.7%; PϽ0.01) but not after ezetimibe treatment (5.6Ϯ0.5% versus 5.8Ϯ0.6%; PϭNS). ⌬FDD-VC was substantially reduced after simvastatin but not after ezetimibe treatment. Extracellular superoxide dismutase activity was increased by Ͼ100% (PϽ0.05) after simvastatin but not ezetimibe treatment. Simvastatin treatment increased the number of functionally active endothelial progenitor cells, whereas ezetimibe had no effect. Conclusions-Four weeks of simvastatin treatment improves endothelial function independently of LDL cholesterol lowering, at least in part by reducing oxidant stress. Simvastatin may thereby exert important pleiotropic effects in

Objective-Myeloperoxidase, a heme enzyme that is present and active in human atherosclerotic lesions, provides a source for the generation of proinflammatory chlorinated reactants contributing to endothelial dysfunction. Modification of high-density lipoprotein (HDL) by hypochlorous acid/hypochlorite (HOCl/Oce Ϫ )-generated in vivo by the myeloperoxidase-hydrogen peroxide-chloride system of activated phagocytes-forms a proatherogenic lipoprotein particle that binds to and is internalized by endothelial cells. Methods and Results-Here we show that HDL, modified with physiologically relevant HOCl concentrations, attenuates the expression and activity of vasculoprotective endothelial nitric oxide synthase. HOCl-HDL promotes dislocalization of endothelial nitric oxide synthase from the plasma membrane and perinuclear location of human umbilical venous endothelial cells. We could identify 2-chlorohexadecanal as the active component mediating this inhibitory activity. This chlorinated fatty aldehyde is formed during HOCl-mediated oxidative cleavage of HDL-associated plasmalogen. Conclusion-2-Chlorohexadecanal, produced by the myeloperoxidase-hydrogen peroxide-chloride system of activated phagocytes may act as a mediator of vascular injury associated with ischemia-reperfusion injury, glomerulosclerosis, and atherosclerosis. Key Words: myeloperoxidase Ⅲ 2-chlorinated fatty aldehyde Ⅲ atherosclerosis Ⅲ modified lipids Ⅲ glomerulosclerosis Ⅲ neutrophils A nimal experimentation and clinical studies have provided convincing evidence that the known risk factors for cardiovascular disease can elicit a localized inflammatory response in the vasculature. The changes are most pronounced in endothelial cells and include oxidative stress, increased activation of endothelial signaling pathways, and the consequent adhesion, activation, and degranulation of leukocytes. The myeloperoxidase (MPO)-hydrogen peroxidesystem of stimulated leukocytes, primarily neutrophils, generates hypochlorous acid/hypochlorite (HOCl/Oce Ϫ ), a potent bacterial oxidant in vivo. 1 MPO and HOCl are emerging as critical modulators of vascular injury by promoting inflammatory arterial pathology and subsequent formation of mature plaques. MPO is present and active in human lesion material. 2 HOCl reacts with a wide range of biological substrates, including antioxidants, amines, sulfides, nucleotides, DNA, lipids, and (lipo)proteins. [3][4][5] HOCl-modified (lipo)proteins are present in human 6 -8 and rabbit lesions, 9,10 and disease stage-dependent accumulation of HOCl-modified (lipo)proteins has been reported. 7 Elevated levels of plasma high-density lipoprotein (HDL) protect against atherosclerotic vascular disease. A broad spectrum of potent antioxidant and anti-inflammatory activities has been ascribed to native HDL. 11,12 However, oxidation/modification by HOCl alters the physicochemical and metabolic properties of anti-atherogenic HDL. [13][14][15] In vivo, apolipoprotein A-I, the major apolipoprotein of HDL, represents a selective target for MPO-catalyz...

Nitric oxide (NO) has been implicated in migraine attacks, but the role of NO in migraine remains unclear. We here hypothesize that increased NO in the headache-free period is associated with migraine. One hundred and thirty probands participated in this study. Various parameters of the NO pathway, such as nitrate, nitrite, arginine, citrulline, nitrosylated proteins, asymmetric dimethylarginine, symmetrical dimethylarginine, expression of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase and two polymorphisms of eNOS were investigated. We found significant increased nitrate and decreased nitrite levels in migraineurs in the headache-free period. Nitrate and nitrite levels showed a significant inverse correlation. Logistic regression revealed an odds ratio of 3.6 for migraine. Other parameters of the NO pathway were neither altered in migraineurs nor correlated with nitrate. We show here that migraine patients suffer under sustained increased nitrosative stress in the headache-free period, which is associated with a 3.6-fold higher risk for migraine.

Metabolic syndrome is associated with disturbances in gut microbiota composition. We aimed to investigate the effect of Lactobacillus casei Shirota (LcS) on gut microbiota composition, gut barrier integrity, intestinal inflammation and serum bile acid profile in metabolic syndrome. In a single-centre, prospective, randomised controlled pilot study, 28 subjects with metabolic syndrome received either LcS for 12 weeks (n = 13) or no LcS (n = 15). Data were compared to healthy controls (n = 16). Gut microbiota composition was characterised from stool using 454 pyrosequencing of 16S rRNA genes. Serum bile acids were quantified by tandem mass spectrometry. Zonulin and calprotectin were measured in serum and stool by ELISA. Bacteroidetes/Firmicutes ratio was significantly higher in healthy controls compared to metabolic syndrome but was not influenced by LcS. LcS supplementation led to enrichment of Parabacteroides. Zonulin and calprotectin were increased in metabolic syndrome stool samples but not influenced by LcS supplementation. Serum bile acids were similar to controls and not influenced by LcS supplementation. Metabolic syndrome is associated with a higher Bacteroidetes/Firmicutes ratio and gut barrier dysfunction but LcS was not able to change this. LcS administration was associated with subtle microbiota changes at genus level.Trial RegistrationClinicalTrials.gov NCT01182844

Peripheral leukocytes can exacerbate brain damage by release of cytotoxic mediators that disrupt blood-brain barrier (BBB) function. One of the oxidants released by activated leukocytes is hypochlorous acid (HOCl) formed via the myeloperoxidase (MPO)-H2O2-Cl− system. In the present study we examined the role of leukocyte activation, leukocyte-derived MPO and MPO-generated oxidants on BBB function in vitro and in vivo. In a mouse model of lipopolysaccharide (LPS)-induced systemic inflammation, neutrophils that had become adherent released MPO into the cerebrovasculature. In vivo, LPS-induced BBB dysfunction was significantly lower in MPO-deficient mice as compared to wild-type littermates. Both, fMLP-activated leukocytes and the MPO-H2O2-Cl− system inflicted barrier dysfunction of primary brain microvascular endothelial cells (BMVEC) that was partially rescued with the MPO inhibitor 4-aminobenzoic acid hydrazide. BMVEC treatment with the MPO-H2O2-Cl− system or activated neutrophils resulted in the formation of plasmalogen-derived chlorinated fatty aldehydes. 2-chlorohexadecanal (2-ClHDA) severely compromised BMVEC barrier function and induced morphological alterations in tight and adherens junctions. In situ perfusion of rat brain with 2-ClHDA increased BBB permeability in vivo. 2-ClHDA potently activated the MAPK cascade at physiological concentrations. An ERK1/2 and JNK antagonist (PD098059 and SP600125, respectively) protected against 2-ClHDA-induced barrier dysfunction in vitro. The current data provide evidence that interference with the MPO pathway could protect against BBB dysfunction under (neuro)inflammatory conditions.

Nonalcoholic steatohepatitis (NASH), a progressive form of nonalcoholic fatty liver disease, is one of the most common hepatic diseases in children. We conducted a randomized controlled clinical trial on children with biopsy-proven NASH based on a combinatorial nutritional approach compared with placebo. Participants were assigned to lifestyle modification plus placebo or lifestyle modification plus a mix containing docosahexaenoic acid, choline, and vitamin E (DHA-CHO-VE). Forty children and adolescents participated in the entire trial. The primary outcome was the improvement of liver hyperechogenicity. Secondary outcomes included alterations of alanine aminotransferase (ALT) and other metabolic parameters. Furthermore, changes of serum bile acids (BA) and plasma fibroblast growth factor 19 (FGF19) levels were evaluated as inverse biomarkers of disease severity. At the end of the study, we observed a significant decrease in severe steatosis in the treatment group (50% to 5%, p = 0.001). Furthermore, although the anthropometric and biochemical measurements in the placebo and DHA-CHO-VE groups were comparable at baseline, at the end of the study ALT and fasting glucose levels improved only in the treatment group. Finally, we found that BA levels were not influenced whereas FGF19 levels were significantly increased by DHA-CHO-VE. The results suggest that a combination of DHA, VE, and CHO could improve steatosis and reduce ALT and glucose levels in children with NASH. However, further studies are needed to assess the impact of a DHA and VE combination on repair of liver damage in paediatric NASH.