Background: Only a few randomized dietary intervention studies that investigated the effects of lacto-ovo vegetarian diet (V d ) in clinically healthy omnivorous subjects are available. Methods: We randomly assigned to overweight omnivores with a low-to-moderate cardiovascular risk profile a low-calorie V d compared with a low-calorie Mediterranean diet (MD), each lasting 3 months, with a crossover design. The primary outcome was the difference in body weight, body mass index, and fat mass changes between the 2 groups. Secondary outcomes were differences in circulating cardiovascular disease risk parameters changes between the 2 groups. Results: One hundred eighteen subjects (mean age: 51.1 years, females: 78%) were enrolled. The total participation rate at the end of the study was 84.7%. No differences between the 2 diets in body weight were observed, as reported by similar and significant reductions obtained by both V d (−1.88 kg) and MD (−1.77 kg). Similar results were observed for body mass index and fat mass. In contrast, significant differences between the 2 interventions were obtained for low-density lipoprotein cholesterol, triglycerides, and vitamin B 12 levels. The difference between the V d and MD groups, in terms of end-of-diet values, was recorded at 9.10 mg/dL for low-density lipoprotein cholesterol ( P =0.01), 12.70 mg/dL for triglycerides ( P <0.01), and 32.32 pg/mL for vitamin B 12 ( P <0.01). Finally, no significant difference was found between V d and MD interventions in oxidative stress markers and inflammatory cytokines, except for interleukin-17, which improved only in the MD group. Forty-six participants during the V d period and 35 during the MD period reached the target values for ≥1 cardiovascular risk factor. Conclusions: Both V d and MD were effective in reducing body weight, body mass index, and fat mass, with no significant differences between them. However, V d was more effective in reducing low-density lipoprotein cholesterol levels, whereas MD led to a greater reduction in triglyceride levels. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02641834.

The conversion of peptides or proteins from their soluble native states into intractable amyloid deposits is associated with a wide range of human disorders. Misfolded protein oligomers formed during the process of aggregation have been identified as the primary pathogenic agents in many such conditions. Here, we show the existence of a quantitative relationship between the degree of binding to neuronal cells of different types of oligomers formed from a model protein, HypF-N, and the GM1 content of the plasma membranes. In addition, remarkably similar behavior is observed for oligomers of the Aβ42 peptide associated with Alzheimer’s disease. Further analysis has revealed the existence of a linear correlation between the level of the influx of Ca2+ across neuronal membranes that triggers cellular damage, and the fraction of oligomeric species bound to the membrane. Our findings indicate that the susceptibility of neuronal cells to different types of misfolded oligomeric assemblies is directly related to the extent of binding of such oligomers to the cellular membrane.

SummaryIncreasing evidence suggests that the interaction of misfolded protein oligomers with cell membranes is a primary event resulting in the cytotoxicity associated with many protein-misfolding diseases, including neurodegenerative disorders. We describe here the results of a study on the relative contributions to toxicity of the physicochemical properties of protein oligomers and the cell membrane with which they interact. We altered the amount of cholesterol and the ganglioside GM1 in membranes of SH-SY5Y cells. We then exposed the cells to two types of oligomers of the prokaryotic protein HypF-N with different ultrastructural and cytotoxicity properties, and to oligomers formed by the amyloid-b peptide associated with Alzheimer's disease. We identified that the degree of toxicity of the oligomeric species is the result of a complex interplay between the structural and physicochemical features of both the oligomers and the cell membrane.

In recent years, the relationship between inflammation and thrombosis has been deeply investigated and it is now clear that immune and coagulation systems are functionally interconnected.Inflammation-induced thrombosis is by now considered a feature not only of autoimmune rheumatic diseases, but also of systemic vasculitides such as Behçet’s syndrome, ANCA-associated vasculitis or giant cells arteritis, especially during active disease.These findings have important consequences in terms of management and treatment. Indeed, Behçet’syndrome requires immunosuppressive agents for vascular involvement rather than anticoagulation or antiplatelet therapy, and it is conceivable that also in ANCA-associated vasculitis or large vessel-vasculitis an aggressive anti-inflammatory treatment during active disease could reduce the risk of thrombotic events in early stages.In this review we discuss thrombosis in vasculitides, especially in Behçet’s syndrome, ANCA-associated vasculitis and large-vessel vasculitis, and provide pathogenetic and clinical clues for the different specialists involved in the care of these patients.

Peptides and proteins can convert from their soluble forms into highly ordered fibrillar aggregates, giving rise to pathological conditions ranging from neurodegenerative disorders to systemic amyloidoses. It is increasingly recognized that protein oligomers forming early in the process of fibril aggregation represent the pathogenic species in protein deposition diseases. The N-terminal domain of the HypF protein from Escherichia coli (HypF-N) has previously been shown to form, under distinct conditions, two types of HypF-N oligomers with indistinguishable morphologies but distinct structural features at the molecular level. Only the oligomer type exposing hydrophobic surfaces and possessing sufficient structural plasticity is toxic (type A), whereas the other type is benign to cultured cells (type B). Here we show that only type A oligomers are able to induce a Ca2+ influx from the cell medium to the cytosol, to penetrate the plasma membrane, to increase intracellular reactive oxygen species production, lipid peroxidation and release of intracellular calcein, resulting in the activation of the apoptotic pathway. Remarkably, these oligomers can also induce a loss of cholinergic neurons when injected into rat brains. By contrast, markers of cellular stress and viability were unaffected in cultured and rat neuronal cells exposed to type B oligomers. The analysis of the time scales of such effects indicates that the difference of toxicity between the two oligomer types involve the early events of the toxicity cascade, shedding new light on the mechanism of action of protein oligomers and on the molecular targets for the therapeutic intervention against protein deposition diseases.

SIRT1, an ubiquitous NAD(?)-dependent deacetylase that plays a role in biological processes such as longevity and stress response, is significantly activated in response to reactive oxygen species (ROS) production. Resveratrol (Resv), an important activator of SIRT1, has been shown to exert major health benefits in diseases associated with oxidative stress. In ischemia-reperfusion (IR) injury, a major role has been attributed to the mitogenactivated protein kinase (MAPK) pathway, which is upregulated in response to a variety of stress stimuli, including oxidative stress. In neonatal rat ventricular cardiomyocytes subjected to simulated IR, the effect of Resv-induced SIRT1 activation and the relationships with the MAPK pathway were investigated. Resv-induced SIRT1 overexpression protected cardiomyocytes from oxidative injury, mitochondrial dysfunction, and cell death induced by IR. For the first time, we demonstrate that SIRT1 overexpression positively affects the MAPK pathway-via Akt/ASK1 signaling-by reducing p38 and JNK phosphorylation and increasing ERK phosphorylation. These results reveal a new protective mechanism elicited by Resv-induced SIRT1 activation in IR tissues and suggest novel potential therapeutic targets to manage IR-induced cardiac dysfunction.

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Objective-Among plasma proteins, fibrinogen represents a major target of oxidative modifications. In patients with postacute myocardial infarction (6 months after the acute event), fibrinogen oxidation-induced carbonyls and fibrinogen function were estimated using in vitro and ex vivo approaches. Fibrinogen structural features and clot architecture were also explored. Approach and Results-In 39 patients with post-acute myocardial infarction and 28 age-, sex-, and risk factor-matched controls, oxidative stress markers (in plasma and in purified fibrinogen fractions), thrombin-catalyzed fibrin polymerization, and plasmin-induced fibrin lysis were estimated. Circular dichroism spectra of purified fibrinogen extracts, electron microscopy, and differential interference contrast microscopy analyses of fibrin clots were also performed. Marked signs of oxidative stress in plasma (P<0.01 versus controls) and, correspondingly, an increased extent of fibrinogen carbonylation (3.5-fold over control values; P<0.01 versus controls) were observed in patients. Furthermore, fibrinogen fractions purified from patients exhibited significantly reduced clotting ability and decreased susceptibility to plasmininduced lysis (P<0.01 versus controls). Alterations in fibrinogen secondary structure, as suggested by circular dichroism spectroscopy, and in fibrin clot architecture, as analyzed by electron and differential interference contrast microscopy, were also identified. Conclusions-Here, we report for the first time that patients with post-acute myocardial infarction present with an overall imbalance in redox status and marked fibrinogen carbonylation associated with altered fibrinogen function, thus suggesting a role for carbonylation as a direct mechanism of fibrinogen function. The observed features occur along with modifications in protein structure and in clot architecture. Results SubjectsDemographic and clinical characteristics of the population studied are summarized in Table 1. Oxidative Stress Markers in Plasma and in FibrinogenAs reported in Table 2, patient plasma displayed significantly higher total PC and thiobarbituric acid reactive substances levels, and lower total antioxidant capacity, than healthy controls (P<0.05 versus controls). Plasma total PC was positively and significantly correlated with fibrinogen PC (P<0.05; R=0.555; Figure 1A) and with thiobarbituric acid reactive substances levels (P<0.05; R=0.444; Figure 1B). Purified fibrinogen from patients displayed significantly increased carbonylation (3.5-fold) in comparison with healthy controls (P<0.01; Figure 1C). PC amounts obtained in human, 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH)-challenged purified fibrinogen (SIGMA, Milan, Italy) were comparable with those observed in fibrinogen from patients with post-AMI and resulted significantly increased compared with untreated fibrinogen (Table 3). Circular Dichroism Spectra: Analysis of Secondary StructureSecondary protein structure was analyzed by far-UV circular dichroism spectroscopy (Figure 2). In ...