Arianna Vignini

Coenzyme Q10 treatment in infertile men with idiopathic asthenozoospermia: a placebo-controlled, double-blind randomized trial.

OBJECTIVE To evaluate the effectiveness of coenzyme Q(10) treatment in improving semen quality in men with idiopathic infertility. DESIGN Placebo-controlled, double-blind randomized trial. SETTING Andrology Unit, Department of Internal Medicine, Polytechnic University of Marche, Italy. PATIENT(S) Sixty infertile patients (27-39 years of age) with the following baseline sperm selection criteria: concentration >20 x 10(6)/mL, sperm forward motility <50%, and normal sperm morphology >30%; 55 patients completed the study. INTERVENTION(S) Patients underwent double-blind therapy with coenzyme Q(10), 200 mg/day, or placebo; the study design was 1 month of run-in, 6 months of therapy or placebo, and 3 months of follow-up. MAIN OUTCOME MEASURE(S) Variations in semen parameters used for patient selection and variations of coenzyme Q(10) and ubiquinol concentrations in seminal plasma and spermatozoa. RESULT(S) Coenzyme Q(10) and ubiquinol increased significantly in both seminal plasma and sperm cells after treatment, as well as spermatozoa motility. A weak linear dependence among the relative variations, baseline and after treatment, of seminal plasma or intracellular coenzyme Q(10) and ubiquinol levels and kinetic parameters was found in the treated group. Patients with a lower baseline value of motility and levels of coenzyme Q(10) had a statistically significant higher probability to be responders to the treatment. CONCLUSION(S) The exogenous administration of coenzyme Q(10) increases the level of the same and ubiquinol in semen and is effective in improving sperm kinetic features in patients affected by idiopathic asthenozoospermia.

Effect of homocysteinylation of low density lipoproteins on lipid peroxidation of human endothelial cells

Homocysteine‐thiolactone (HcyT) is a toxic product whose synthesis is directly proportional to plasma homocysteine (Hcy) levels. Previous studies demonstrated that the interaction between HcyT and low density lipoproteins (LDL) induces the formation of homocystamide‐LDL adducts (Hcy‐LDL). Structural and functional alterations of Hcy‐LDL have been described and it has been suggested that homocysteinylation could increase atherogenicity of LDL. Oxidative damage of endothelial cells (EC) is considered to be a critical aspect of the atherosclerotic process. To further investigate the molecular mechanisms involved in the atherogenicity of homocysteinylated LDL, we studied the effect of interaction between Hcy‐LDL and EC on cell oxidative damage, using human aortic endothelial cells (HAEC) as experimental model. Homocysteinylation of LDL was carried out by incubation of LDL, isolated from plasma of healthy normolipemic subjects, with HcyT (10–100 μM). In our experimental conditions, homocysteinylation treatment was not accompanied by oxidative damage of LDL. No modifications of apoprotein structure and physico‐chemical properties were observed in Hcy‐LDL with respect to control LDL (c‐LDL), as evaluated using the intrinsic fluorescence of tryptophan and the probe Laurdan incorporated in lipoproteins. Our results demonstrated that Hcy‐LDL incubated at 37°C for 3 h with HAEC, induced an oxidative damage on human EC with a significant increase of lipid hydroperoxides in cells incubated with Hcy‐LDL with respect to cell incubated with c‐LDL. The compositional changes were associated with a significant decrease viability in cells treated with Hcy‐LDL. The relationship between the levels of –SH groups of LDL and the oxidative damage of HAEC has been demonstrated. These results suggest that Hcy‐LDL exert a cytotoxic effect that is likely related to an increase in lipid peroxidation and oxidative damage of EC.

Reactive oxygen species plasmatic levels in ischemic stroke

Oxidative stress is probably one of the mechanisms involved in neuronal damage induced by ischemia-reperfusion, and the antioxidant activity of plasma may be an important factor providing protection from neurological damage caused by stroke-associated oxidative stress. The aim of this study was to investigate the status of oxidative stress, NO and ONOO− levels in patients with atherothrombotic and lacunar acute ischemic stroke and iNOS, eNOS and nitrotyrosine expression in the same patients. Plasma ONOO− levels were significantly higher in patients than in controls while NO decreases in patients in respect to controls. Densitometric analysis of bands indicated that iNOS and N-Tyr protein levels were significantly higher in patients in respect to controls. This study has highlighted a significant NO decrease in our patients compared with controls and this is most probably due to the increased expression of inducible NO synthase by the effect of thrombotic attack. In fact, the constitutive NO isoforms, which produce small amounts of NO, are beneficial, while activation of the inducible isoform of NO, which produces much more NO, causes injury, being its toxicity greatly enhanced by generation of peroxynitrite. The significant ONOO− increase observed in our patients, compared to controls, is most probably due to reaction of NO with O2·−. These findings suggest that free radical production and oxidative stress in ischemic stroke might have a major role in the pathogenesis of ischemic brain injury. Peroxynitrite might be the main marker of brain damage and neurological impairment in acute ischemic stroke.

Oxidative Stress and Erythrocyte Membrane Alterations in Children with Autism: Correlation with Clinical Features

It has been suggested that oxidative stress may play a role in the pathogenesis of Autism Spectrum Disorders (ASD), but the literature reports somewhat contradictory results. To further investigate the issue, we evaluated a high number of peripheral oxidative stress parameters, and some related issues such as erythrocyte membrane functional features and lipid composition. Twenty-one autistic children (Au) aged 5 to 12 years, were gender and age-matched with 20 typically developing children (TD). Erythrocyte thiobarbituric acid reactive substances, urinary isoprostane and hexanoyl-lysine adduct levels were elevated in Au, thus confirming the occurrence of an imbalance of the redox status of Au, whilst other oxidative stress markers or associated parameters (urinary 8-oxo-dG, plasma radical absorbance capacity and carbonyl groups, erythrocyte superoxide dismutase and catalase activities) were unchanged. A very significant reduction of Na+/K+-ATPase activity (−66%, p<0.0001), a reduction of erythrocyte membrane fluidity and alteration in erythrocyte fatty acid membrane profile (increase in monounsaturated fatty acids, decrease in EPA and DHA-ω3 with a consequent increase in ω6/ω3 ratio) were found in Au compared to TD, without change in membrane sialic acid content. Some Au clinical features appear to be correlated with these findings; in particular, hyperactivity score appears to be related with some parameters of the lipidomic profile and membrane fluidity. Oxidative stress and erythrocyte membrane alterations may play a role in the pathogenesis of ASD and prompt the development of palliative therapeutic protocols. Moreover, the marked decrease in NKA could be potentially utilized as a peripheral biomarker of ASD.

Modifications of platelet from Alzheimer disease patients: a possible relation between membrane properties and NO metabolites.

Alzheimer disease (AD) is a chronic neurodegenerative disorder characterised by a progressive loss of memory and cognitive functions. The formation of nitric oxide (NO), by astrocytes, has been suggested to contribute to the neurodegnerative process. Some studies have described the participation of different isoforms of NOS in the progression of AD. The present work was conducted in order to investigate the role played by NO and peroxynitrite in platelets from AD patients, the possible correlation with Na(+)/K(+)-ATPase activity and the intracellular Ca(2+) in the same group of patients as well as the expression of NOS isoenzymes and nitrotyrosine as markers of NO synthesis and reactive protein nitration. NO production was significantly elevated in the platelets from AD patients compared to controls as well as l-arginine/NO-dependent ONOO(-). Membrane Na(+)/K(+)-ATPase activity was significantly decreased in patients than in controls while intracellular Ca(2+) concentration shows an opposite trend. Platelet from AD patients showed a significantly increased 1-[4-(trimethylammonio)phenyl]-6-phenyl-1,3,5-hexatriene (TMA-DPH) and 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence anisotropy compared with controls. Western blot analysis using anti-iNOS and eNOS monoclonal antibodies demonstrated that both isoforms were detectable in cell lysates as well as nitrotyrosine more pronounced in the cell lysates from AD patients than controls. In conclusion, the increased expression and activity of nitrergic system may produce platelet membrane alteration or vice versa. These modifications may contribute further to the neurodegenerative process in AD because the abnormal function of Alzheimer platelets play a very important role in the pathogenesis of the disease.

Alzheimer's Disease and Diabetes: New Insights and Unifying Therapies

Several research groups have begun to associate the Alzheimer Disease (AD) to Diabetes Mellitus (DM), obesity and cardiovascular disease. This relationship is so close that some authors have defined Alzheimer Disease as Type 3 Diabetes. Numerous studies have shown that people with type 2 diabetes have twice the incidence of sporadic AD. Insulin deficiency or insulin resistance facilitates cerebral β-amyloidogenesis in murine model of AD, accompanied by a significant elevation in APP (Amyloid Precursor Protein) and BACE1 (β-site APP Cleaving Enzime 1). Similarly, deposits of Aβ produce a loss of neuronal surface insulin receptors and directly interfere with the insulin signaling pathway. Furthermore, as it is well known, these disorders are both associated to an increased cardiovascular risk and an altered cholesterol metabolism, so we have analyzed several therapies which recently have been suggested as a remedy to treat together AD and DM. The aim of the present review is to better understand the strengths and drawbacks of these therapies.

Oxidative stress in ischaemic stroke.

Eur J Clin Invest 2011; 41 (12): 1318–1322

Nitric oxide production during the osteogenic differentiation of human periodontal ligament mesenchymal stem cells

The critical tissues that require regeneration in the periodontium are of mesenchymal origin; therefore, the ability to identify, characterize and manipulate mesenchymal stem cells within the periodontium is of considerable clinical significance. In particular, recent findings suggest that periodontal ligament cells may possess many osteoblast-like properties. In the present study, periodontal ligament mesenchymal stem cells obtained from healthy volunteers were maintained in culture until confluence and then induced to osteogenic differentiation. Intracellular calcium ([Ca2+](i)) concentration and nitric oxide, important signalling molecules in the bone, were measured along with cell differentiation. Alkaline phosphatase activity was assayed and bone nodule-like structures were evaluated by means of morphological and histochemical analysis. Our results showed that the periodontal ligament mesenchymal stem cells underwent an in vitro osteogenic differentiation, resulting in the appearance of active osteoblast-like cells together with the formation of calcified deposits. Differentiating cells were also characterized by an increase of [Ca2+](i) and nitric oxide production. In conclusion, our data show a link between nitric oxide and the osteogenic differentiation of human periodontal ligament mesenchymal stem cells, thus suggesting that local reimplantation of expanded cells in conjugation with a nitric oxide donor could represent a promising method for treatment of periodontal defects.

Prognostic significance of personality profiles in patients with chronic migraine.

Background and Objective.—The aim of this study was to assess whether the psychological profile may have prognostic significance in chronic migraine patients.

Single Nucleotide Polymorphism (SNP) of the Endothelial Nitric Oxide Synthase (eNOS) Gene (Glu298Asp Variant) in Infertile Men With Asthenozoospermia

The objective of this study was to elucidate the missense Glu298Asp polymorphism within exon 7 of the endothelial nitric oxide synthase (eNOS) gene in infertile men with asthenozoospermia and its potential role in sperm motility. In this prospective controlled study conducted in our andrology unit, we investigated the frequency of the 894G>T polymorphism (Glu298Asp variant) within exon 7 of the eNOS gene in 70 infertile men and 60 healthy men. Sperm motion kinetics were assessed with computer-assisted semen analysis. The presence of G>T, a single nucleotide polymorphism (SNP) in exon 7 of the eNOS gene (NCBI SNP cluster rs1799983; GenBank accession number NG_011992; protein accession number NP_000594) was determined by allelespecific polymerase chain reaction followed by restriction fragment length polymorphism analysis. Sequencing analysis was used to confirm the specific genotype. The 894G>T eNOS allele (T) was found at a higher frequency in the patients with asthenozoospermia (60% vs 22.5% in the control group; P = .02). The percentage of progressive motile sperm (grade a + b) was lower in the asthenozoospermic infertile men with the homozygous eNOS (TT) genotype than in the wild-type eNOS (GG) (P = .02) and heterozygous eNOS (GT) genotypes (P = .01). However, the percentage of progressive motile sperm (grade a + b) was higher in the wild-type vs mutant eNOS (TT) (P = .03) and heterozygous eNOS (GT) genotypes (P = .04). Our findings suggest that the T allele encoding for aspartic acid of the eNOS (Glu298Asp) gene may contribute to poor sperm motility.