Study of intracellular signaling pathways triggered by natural antioxidants in human endothelial cells

Cardiovascular (CV) benefits of Natural Antioxidant (NA) supplementation are contradictory. Endothelial Cells (EC) are pivotal player on CV diseases onset/progression and thus represent a good model to study the NA impact on vascular pathophysiology. We show that two NA, coumaric acid and resveratrol, affect intracellular ROS levels and cell physiology in human EC. While at lower doses both compounds were antioxidant, at mildly high doses they became pro-oxidant, eliciting cell death by apoptosis and phospho-Akt inhibition. Pro-oxidant effects were counteracted by diphenyleneiodonium, hinting a role for flavin oxidases in NA-induced toxicity. ECs treatment with the mitochondrial permeability transition pore inhibitor prevented oxidative cell damage indicating mitochondrial involvement in NA-induced ECs impairment. Pro-oxidant effects were also hindered by sulfaphenazole (SPZ), suggesting a role for CYP2C9 in NA-induced toxicity. SPZ also prevented NA-induced p-Akt down-regulation and mitochondrial membrane potential (MMP) impairment indicating that Akt works downstream of CYP2C9 in mediating cellular responses to NA. Stimulation of p-Akt by insulin, counteracted NA-induced MMP impairment and cell death, an effect abolished by Akt inhibitors further suggesting that Akt regulates cell survival in response to NA-induced stress. Our study show that mildly high-doses of NA induce mitochondria-dependent cell damage mediated by CYP2C9 and the Akt pathway in a human vascular model

Esperienza di interoperabilità tra servizi interbibliotecari tramite protocollo ISO-ILL. Colloquio standard ILL- SBN/aleph e ILL-SBN /sebina open library

L’intervento illustra le caratteristiche di interoperabilità di ILL-SBN e in particolare l’integrazione in modalità standard ISO-ILL con i software Aleph500 e Sebina OpenLibrary. Il colloquio con le biblioteche Aleph è stato reso possibile dalla cooperazione con l’Associazione Italiana Utenti ExLibris (ITALE) che ha portato all’approfondimento dello standard (con revisione delle rispettive configurazioni) e all’interoperabilità tra i due sistemi attraverso la realizzazione di un gateway HTTP/TCP-IP. Il colloquio con le biblioteche Sebina OpenLibrary è stato realizzato direttamente via http in modalità nativa ILL- SBN. L’intervento descrive inoltre l’esperienza comune nell’ambito del Gruppo di lavoro per il colloquio tra ILL- SBN e altri applicativi, le riflessioni e le esigenze emerse e i vantaggi per le biblioteche; propone infine la cooperazione allargata per la realizzazione di un servizio nazionale integrato.The aim of this paper is to explain how ILL-SBN can interoperate with other ILS, with particular reference to Sebina OpenLibrary and Aleph500. Interoperability with Aleph500 has been obtained through cooperation with ITALE (Italian association of Ex Libris users); extensive testing has brought to review the configurations of both ILL-SBN and Aleph installations and to realize a HTTP/TCP-IP gateway. Interoperability with Sebina OpenLibrary has been made directly via HTTP. The paper describes also the experience of the working group and what we think are the advantages of cooperation and interoperability in the present Italian situation. Our proposal is to broaden the cooperation with a view to realize a national integrated service

Neuropsychological Phenotype in Wolf-Hirschhorn Syndrome

The Wolf-Hirschhorn syndrome (WHS) is a rare genetic disorder that causes a range of intellectual disability from mild to severe. In this study, we used standard tools to psychometrically characterize the specific neuropsychological phenotype of WHS. We studied 57 individuals with WHS, ranging in age from 2.6 to 28.6 years representing 70% of the certified Italian WHS population. Results obtained by administering Griffiths' Mental Developmental Scales and the Vineland Adaptive Behavior Scale revealed a typical WHS neuropsychological phenotype characterized by specific strengths and weaknesses. Despite their severe cognitive impairment, in both scales, patients showed better communication and social interaction skills compared to visuo-motor abilities. Results of our study could bring to the development of new and more effective treatments for individuals affected by WHS: based on neuropsychological phenotype description, it should be possible to design specific rehabilitation programs. These programs would then be aimed at improving rehabilitation protocols to optimize the developmental potential and personal independence of individuals with WHS and thus to improve their quality of life

Apricot melanoidins prevent oxidative endothelial cell death by counteracting mitochondrial oxidation and membrane depolarization

The cardiovascular benefits associated with diets rich in fruit and vegetables are thought to be due to phytochemicals contained in fresh plant material. However, whether processed plant foods provide the same benefits as unprocessed ones is an open question. Melanoidins from heat-processed apricots were isolated and their presence confirmed by colorimetric analysis and browning index. Oxidative injury of endothelial cells (ECs) is the key step for the onset and progression of cardiovascular diseases (CVD), therefore the potential protective effect of apricot melanoidins on hydrogen peroxide-induced oxidative mitochondrial damage and cell death was explored in human ECs. The redox state of cytoplasmic and mitochondrial compartments was detected by using the redox-sensitive, fluorescent protein (roGFP), while the mitochondrial membrane potential (MMP) was assessed with the fluorescent dye, JC-1. ECs exposure to hydrogen peroxide, dose-dependently induced mitochondrial and cytoplasmic oxidation. Additionally detected hydrogen peroxide-induced phenomena were MMP dissipation and ECs death. Pretreatment of ECs with apricot melanoidins, significantly counteracted and ultimately abolished hydrogen peroxide-induced intracellular oxidation, mitochondrial depolarization and cell death. In this regard, our current results clearly indicate that melanoidins derived from heat-processed apricots, protect human ECs against oxidative stress

Human serum albumin increases the stability of green tea catechins in aqueous physiological conditions

Epicatechin (EC), epigallocatechin (EGC), epicatechingallate (ECG) and epigallocatechingallate (EGCG) are antioxidants present in the green tea, a widely used beverage whose health benefits are largely recognized. Nevertheless, major physicochemical limitations, such as the high instability of catechins, pose important questions concerning their potential pharmacological use. Recent studies indicate that binding of catechins with plasmatic proteins may modulate their plasma concentration, tissue delivery and biological activity. After 5 minutes of incubation with HSA both ECG and EGCG were fully bound to HSA, while after 48h incubation only 41% of EC and 70% of EGC resulted linked. HSA had a strong stabilizing effect on all catechins, which could be found in solution between 29 and 85% even after 48h of incubation. In the absence of HSA, EGC and EGCG disappeared in less than 24h, while ECG and EC were found after 48h at 5 and 50%, respectively. The stabilizing effect of HSA toward EGCG, obtained in aqueous physiological conditions, resulted stronger in comparison to cysteine and HCl, previously reported to stabilize this polyphenol. Because of the multitude of contradictory data concerning in vivo and in vitro antioxidant-based experimentations, we believe our work may shed some light on this debated field of research

Oxidative stress-dependent activation of collagen synthesis is induced in human pulmonary smooth muscle cells by sera from patients with scleroderma-associated pulmonary hypertension

Pulmonary arterial hypertension is a major complication of systemic sclerosis. Although oxidative stress, intima hyperplasia and a progressive vessel occlusion appear to be clearly involved, the fine molecular mechanisms underpinning the onset and progression of systemic sclerosis-associated pulmonary arterial hypertension remain largely unknown. Here we shows for the first time that an increase of NADPH-derived reactive oxygen species production induced by sera from systemic sclerosis patients with pulmonary arterial hypertension drives collagen type I promoter activity in primary human pulmonary artery smooth muscle cells, suggesting that antioxidant-based therapies should be considered in the treatment of systemic sclerosis-associated vascular diseases

Flavin Oxidase-Induced ROS Generation Modulates PKC Biphasic Effect of Resveratrol on Endothelial Cell Survival.

Dietary intake of natural antioxidants is thought to impart protection against oxidative-associated cardiovascular diseases. Despite many in vivo studies and clinical trials, this issue has not been conclusively resolved. Resveratrol (RES) is one of the most extensively studied dietary polyphenolic antioxidants. Paradoxically, we have previously demonstrated that high RES concentrations exert a pro-oxidant effect eventually elevating ROS levels leading to cell death. Here, we further elucidate the molecular determinants underpinning RES-induced oxidative cell death. Using human umbilical vein endothelial cells (HUVECs), the effect of increasing concentrations of RES on DNA synthesis and apoptosis was studied. In addition, mRNA and protein levels of cell survival or apoptosis genes, as well as protein kinase C (PKC) activity were determined. While high concentrations of RES reduce PKC activity, inhibit DNA synthesis and induce apoptosis, low RES concentrations elicit an opposite effect. This biphasic concentration-dependent effect (BCDE) of RES on PKC activity is mirrored at the molecular level. Indeed, high RES concentrations upregulate the proapoptotic , while downregulating the antiapoptotic , at both mRNA and protein levels. Similarly, high RES concentrations downregulate the cell cycle progression genes, , ornithine decarboxylase and cyclin D1 protein levels, while low RES concentrations display an increasing trend. The BCDE of RES on PKC activity is abrogated by the ROS scavenger Tempol, indicating that this enzyme acts downstream of the RES-elicited ROS signaling. The RES-induced BCDE on HUVEC cell cycle machinery was also blunted by the flavin inhibitor diphenyleneiodonium (DPI), implicating flavin oxidase-generated ROS as the mechanistic link in the cellular response to different RES concentrations. Finally, PKC inhibition abrogates the BCDE elicited by RES on both cell cycle progression and pro-apoptotic gene expression in HUVECs, mechanistically implicating PKC in the cellular response to different RES concentrations. Our results provide new molecular insight into the impact of RES on endothelial function/dysfunction, further confirming that obtaining an optimal benefit of RES is concentration-dependent. Importantly, the BCDE of RES could explain why other studies failed to establish the cardio-protective effects mediated by natural antioxidants, thus providing a guide for future investigation looking at cardio-protection by natural antioxidants

Novel docetaxel-loaded nanoparticles based on poly(lactide-co-caprolactone) and poly(lactide-co-glycolide-co-caprolactone) for prostate cancer treatment: formulation, characterization, and cytotoxicity studies

Docetaxel (Dtx) chemotherapy is the optional treatment in patients with hormone-refractory metastatic prostate cancer, and Dtx-loaded polymeric nanoparticles (NPs) have the potential to induce durable clinical responses. However, alternative formulations are needed to overcome the serious side effects, also due to the adjuvant used, and to improve the clinical efficacy of the drug

Antioxidant Activity Mediates Pirfenidone Antifibrotic Effects in Human Pulmonary Vascular Smooth Muscle Cells Exposed to Sera of Idiopathic Pulmonary Fibrosis Patients.

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by an exacerbated fibrotic response. Although molecular and cellular determinants involved in the onset and progression of this devastating disease are largely unknown, an aberrant remodeling of the pulmonary vasculature appears to have implications in IPF pathogenesis. Here, we demonstrated for the first time that an increase of reactive oxygen species (ROS) generation induced by sera from IPF patients drives both collagen type I deposition and proliferation of primary human pulmonary artery smooth muscle cells (HPASMCs). IPF sera-induced cellular effects were significantly blunted in cells exposed to the NADPH oxidase inhibitor diphenyleneiodonium (DPI) proving the causative role of ROS and suggesting their potential cellular source. Contrary to IPF naive patients, sera from Pirfenidone-treated IPF patients failed to significantly induce both ROS generation and collagen synthesis in HPASMCs, mechanistically implicating antioxidant properties as the basis for the in vivo effect of this drug

NADPH-derived ROS generation drives fibrosis and endothelial-to-mesenchymal transition in systemic sclerosis: Potential cross talk with circulating miRNAs

Systemic sclerosis (SSc) is an immune disorder characterized by diffuse fibrosis and vascular abnormalities of the affected organs. Although the etiopathology of this disease is largely unknown, endothelial damage and oxidative stress appear implicated in its initiation and maintenance. Here, we show for the first time that circulating factors present in SSc sera increased reactive oxygen species (ROS) production, collagen synthesis, and proliferation of human pulmonary microvascular endothelial cells (HPMECs). The observed phenomena were also associated with endothelial to mesenchymal transition (EndMT) as indicated by decreased von Willebrand factor (vWF) expression and increased alpha-smooth muscle actin, respectively, an endothelial and mesenchymal marker. SSc-induced fibroproliferative effects were prevented by HPMECs exposition to the NADPH oxidase inhibitor diphenyleneiodonium, demonstrating ROS's causative role and suggesting their cellular origin. Sera from SSc patients showed significant changes in the expression of a set of fibrosis/EndMT-associated microRNAs (miRNA), including miR-21, miR-92a, miR-24, miR-27b, miR-125b, miR-29c, and miR-181b, which resulted significantly upregulated as compared to healthy donors sera. However, miR29b resulted downregulated in SSc sera, whereas no significant differences were found in the expression of miR-29a in the two experimental groups of samples. Taking together our data indicate NADPH oxidase-induced EndMT as a potential mechanism of SSc-associated fibrosis, suggesting fibrosis-associated miRNAs as potentially responsible for initiating and sustaining the vascular alterations observed in this pathological condition.Grants from the University of Sharjah (Seed 2001050151, collaborative 2101050160), fondo UNISS di Ateneo per la Ricerca 2020, and Fondo di Sviluppo e Coesione 2014–2020, Patto per lo Sviluppo della Regione Sardegna, L.R.7-2017-RASSR82005