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Reactive oxygen species (ROS) are produced constantly inside the cells as a consequence of nutrient catabolism. The balance between ROS production and elimination allows to maintain cell redox homeostasis and biological functions, avoiding the occurrence of oxidative distress causing irreversible oxidative damages. A fundamental player in this fine balance is reduced glutathione (GSH), required for the scavenging of ROS as well as of the reactive 2-oxoaldehydes methylglyoxal (MGO). MGO is a cytotoxic compound formed constitutively as byproduct of nutrient catabolism, and in particular of glycolysis, detoxified in a GSH-dependent manner by the glyoxalase pathway consisting in glyoxalase I and glyoxalase II reactions. A physiological increase in ROS production (oxidative eustress, OxeS) is promptly signaled by the decrease of cellular GSH/GSSG ratio which can induce the reversible S-glutathionylation of key proteins aimed at restoring the redox balance. An increase in MGO level also occurs under oxidative stress (OxS) conditions probably due to several events among which the decrease in GSH level and/or the bottleneck of glycolysis caused by the reversible S-glutathionylation and inhibition of glyceraldehyde-3-phosphate dehydrogenase. In the present review, it is shown how MGO can play a role as a stress signaling molecule in response to OxeS, contributing to the coordination of cell metabolism with gene expression by the glycation of specific proteins. Moreover, it is highlighted how the products of MGO metabolism, S-D-lactoylglutathione (SLG) and D-lactate, which can be taken up and metabolized by mitochondria, could play important roles in cell response to OxS, contributing to cytosol-mitochondria crosstalk, cytosolic and mitochondrial GSH pools, energy production, and the restoration of the GSH/GSSG ratio. The role for SLG and glyoxalase II in the regulation of protein function through S-glutathionylation under OxS conditions is also discussed. Overall, the data reported here stress the need for further studies aimed at understanding what role the evolutionary-conserved MGO formation and metabolism can play in cell signaling and response to OxS conditions, the aberration of which may importantly contribute to the pathogenesis of diseases associated to elevated OxS.

The use of glyceryl monooleate (GMO)-based nanoparticles has not yet been explored in overcoming the low bioavailability of Epigallocatechin-3-gallate (EGCG), a green tea polyphenol with a known anticancer activity. Since the inclusion of a guest molecule can affect the curvature and the supramolecular structure of fully hydrated GMO-based phase, the phase behavior of bulk and dispersed liquid crystalline systems containing EGCG were explored by Small Angle Neutron Scattering and X-Ray Diffraction experiments. Molecular Dynamic Simulations showed how the interaction of EGCG with polar heads of GMO strongly affects the curvature and packing of GMO phase. The EGCG encapsulation efficiency was determined in the nanodispersions and their size studied by Dynamic Light Scattering and Atomic Force Microscopy. A nanodispersed formulation has been optimized with a cytotoxic effect more than additive of GMO and EGCG.

S-glutathionylation, the reversible formation of a mixed disulfide bridge between a specific cysteine and a glutathione molecule, can occur spontaneously or be catalyzed by enzymes. Glyoxalase II (GloII), using its natural substrate SLG can form specific protein-SSG mixed disulfide leading enzymatic regulation of S-glutathionylation.

Chronic high glucose (HG) exposure increases methylglyoxal (MG)-derived AGEs and is involved in the onset of pathological conditions, such as diabetes, atherosclerosis and chronic‐degenerative diseases. Under physiologic condition the harmful effects of MG are contrasted by glyoxalase system that is involved in the detoxification of Reactive Carbonyl Species (RCS) and maintain the homeostasis of the redox environment of the cell. Polyphenols are the most abundant antioxidants in the diet and present various health benefits. The study aimed at investigating the role of polyphenols extracted from an apple high in polyphenols (Calville White Winter), on glyco-oxidative stress induced by chronic HG-exposure. Intestinal Caco-2 cells were treated in physiological glucose condition (25mM) as a control and in HG condition (50mM) with or without apple extract for one week. Our data demonstrated that HG-treatment triggers glyco-oxidation stress with a significantly increase in ROS, lipid peroxidation, AGEs and Glyoxalase I (GlxI) activity with a significant decrease in total antioxidant intracellular defense. Treatment with polyphenols under HG condition restores to the control levels GlxI activity, decreases Glyoxalase II (GlxII) in relation to the control and induces a drop of glyco-oxidative damage. This paper seeks to highlight the roles of polyphenols in glyco-oxidative stress.

Cystic fibrosis (CF) is a hereditary disease, with 70% of patients developing a proteinopathy related to the deletion of phenylalanine 508. CF is associated with multiple organ dysfunction, chronic inflammation, and recurrent lung infections. CF is characterized by defective autophagy, lipid metabolism, and immune response. Intracellular lipid accumulation favors microbial infection, and autophagy deficiency impairs internalized pathogen clearance. Myriocin, an inhibitor of sphingolipid synthesis, significantly reduces inflammation, promotes microbial clearance in the lungs, and induces autophagy and lipid oxidation. RNA-seq was performed in Aspergillusfumigatus-infected and myriocin-treated CF patients&rsquo, derived monocytes and in a CF bronchial epithelial cell line. Fungal clearance was also evaluated in CF monocytes. Myriocin enhanced CF patients&rsquo, monocytes killing of A. fumigatus. CF patients&rsquo, monocytes and cell line responded to infection with a profound transcriptional change, myriocin regulates genes that are involved in inflammation, autophagy, lipid storage, and metabolism, including histones and heat shock proteins whose activity is related to the response to infection. We conclude that the regulation of sphingolipid synthesis induces a metabolism drift by promoting autophagy and lipid consumption. This process is driven by a transcriptional program that corrects part of the differences between CF and control samples, therefore ameliorating the infection response and pathogen clearance in the CF cell line and in CF peripheral blood monocytes.

The influence of a lipophilic derivative of Edaravone (C18Edv) on a POPC liposomal bilayer has been investigated by a combined computational-experimental approach. The order and hydration degree of three different systems composed by 10%, 20% and 40% in w/w percentage of C18Edv respect to POPC were investigated through Molecular Dynamics (MD) simulations and fluorescence spectroscopy experiments. Dynamic Light Scattering measurements showed how the presence of different amounts of C18EdV determines differences on liposome size and stability. The survey revealed that the content of lipophilic antioxidant tunes liposome rigidity and influences cellular uptake and antioxidant activity which are maximized for formulation containing 20% of C18Edv.

The epidermal growth factor receptor (EGFR) is one of the most well-studied molecular targets in non-small cell lung cancer (NSCLC) and tyrosine kinase inhibitors have been shown to be effective in the treatment of advanced NSCLC. Nevertheless, the efficacy of tyrosine kinase inhibitors could be compromised by additional mutations in EGFR and compensatory activations of other pathways. Epigallocatechin-3-gallate (EGCG), the main bioactive molecule in green tea, acts as a tyrosine kinase inhibitor toward cancer cells overexpressing EGFR (wild-type). However, little information has been reported on the effect of EGCG on EGFR with activating mutations. In this study, we evaluated the ability of EGCG to inhibit EGFR signaling activation in three different NSCLC cell lines containing wild-type EGFR or EGFR with additional mutations. The effect on proliferation, apoptosis, migration, and vinculin expression was then studied. Overall, our results demonstrate that EGCG polyphenol inhibits cell proliferation and migration in NSCLC cell lines, although with different efficacy and mechanisms. These data may be of interest for an evaluation of the use of EGCG as an adjunct to NSCLC therapies.

Liposomes are versatile platforms to carry anticancer drugs in targeted drug delivery; they can be surface modified by different strategies and, when coupled with targeting ligands, are able to increase cellular internalisation and organelle-specific drug delivery. An interesting strategy of antitumoral therapy could involve the use of lysosomotropic ligand-targeted liposomes loaded with molecules, which can induce lysosomal membrane permeabilization (LMP), leakage of cathepsins into the cytoplasm and subsequent apoptosis. We have previously demonstrated the ability of liposomes functionalised with a mannose-6-phosphate to reach lysosomes; in this research we compare the behaviour of M6P-modified and non-functionalised liposomes in MCF7 tumour cell and in HDF normal cells. With this aim, we first demonstrated by Western blotting the overexpression of mannose-6-phosphate/insulin-like growth factor (M6P/IGF-II) receptor in MCF7. Then, we prepared calcein-loaded liposomes and we revealed the increased uptake of M6P-functionalised liposomes in MCF7 cells respect to HDF cells by flow cytometry analysis. Finally, we loaded functionalised and not functionalised liposomes with N-hexanoyl-d-erythro-sphingosine (C6Cer), able to initiate LMP-induced apoptosis; after having studied the stability of both vesicles in the presence of serum by Dynamic Light Scattering and Spectrophotometric turbidity measurements, we showed that ceramide-loaded M6P-liposomes significantly increased apoptosis in MCF7 with respect to HDF cells.

Glutathione is a very ancient molecule widely distributed in aerobic cells and organisms, either prokaryotes or eukaryotes. Since glutathione in not found in anaerobic cells it could have evolved in the course of the adaptation to the presence of oxygen in the atmosphere. Glutathione is the major non-protein low molecular weight antioxidant and the most important cellular thiol reducing agent. Glutathione biosynthesis occurs in the cytosol from its constituent amino acids; GSH is present also in the most important cellular districts like mitochondria and nucleus to indicate its central role in several metabolic pathways and protective mechanisms. There are several glutathione dependent enzymes involved in various steps of cell metabolism. GSH is a key antioxidant that modulates various cellular processes and therefore is determinant for redox signaling, xenobiotics’s detoxication, regulation of cell proliferation, apoptosis and immune functions. Glutathione concentration and redox state is due to a complex interaction between biosynthesis, utilization, degradation, and transport. All these factors are of great importance for understanding the significance of cellular redox balance and its correlation with pathological conditions.

Dicarbonyl stress is a dysfunctional state consisting in the abnormal accumulation of reactive α-oxaldehydes leading to increased protein modification. In cells, post-translational changes can also occur through S-glutathionylation, a highly conserved oxidative post-translational modification consisting of the formation of a mixed disulfide between glutathione and a protein cysteine residue. This review recapitulates the main findings supporting a role for dicarbonyl stress and S-glutathionylation in the pathogenesis of cerebrovascular diseases, with specific emphasis on cerebral cavernous malformations (CCM), a vascular disease of proven genetic origin that may give rise to various clinical signs and symptoms at any age, including recurrent headaches, seizures, focal neurological deficits, and intracerebral hemorrhage. A possible interplay between dicarbonyl stress and S-glutathionylation in CCM is also discussed.

Cushing syndrome (CS), caused by glucocorticoid (GCs) excess, is strictly connected to onset of different metabolic diseases and impaired wound healing. The source of excessively high levels of GCs allows the identification of endogenous and exogenous (iatrogenic) CS. Iatrogenic patients usually receive also anti-metabolites serving as the foundation to modern steroid-sparing immunosuppressive therapy. Tissues mainly targeted by CS are bone and fat, both derived from progenitor cells named mesenchymal stem cells (MSCs). In addition, the pathogenic role of MSCs in other diseases sharing common properties with CS, such as an altered inflammatory profile and increased oxidative stress, has been identified. In this light, MSCs isolated from skin of control healthy subjects (C-MSCs), patients affected by endogenous CS (ENDO-MSCs), patients affected by iatrogenic CS (IATRO-MSCs) and patients affected by exogenous CS receiving steroid-sparing drugs (SS-MSCs), respectively, have been isolated and analyzed. ENDO- and IATRO-MSCs showed a reduced differentiative potential toward osteogenic and adipogenic lineages compared to C-MSCs, whereas SS-MSCs re-acquired the ability to differentiate, with a trend similar to control cells. In addition, MSCs from CS groups, compared to control MSCs, displayed a reduction in the secretion of cytokines (immune-suppression), a decreased expression of genes related to wound healing and a dysregulation of the enzymes/genes related to antioxidant capacity. In conclusion, our results suggest that the hallmarks of CS, such as wound healing impairment and immunosuppression, are already detectable in undifferentiated cells, which could be considered a potential therapeutic early target for control of CS.

Glyoxalase II, the second of 2 enzymes in the glyoxalase system, is a hydroxyacylglutathione hydrolase that catalyses the hydrolysis of S-d-lactoylglutathione to form d-lactic acid and glutathione, which is released from the active site. The tripeptide glutathione is the major sulfhydryl antioxidant and has been shown to control several functions, including S-glutathionylation of proteins. S-Glutathionylation is a way for the cells to store reduced glutathione during oxidative stress, or to protect protein thiol groups from irreversible oxidation, and few enzymes involved in protein S-glutathionylation have been found to date. In this work, the enzyme glyoxalase II and its substrate S-d-lactoylglutathione were incubated with malate dehydrogenase or with actin, resulting in a glutathionylation reaction. Glyoxalase II was also submitted to docking studies. Computational data presented a high propensity of the enzyme to interact with malate dehydrogenase or actin through its catalytic site and further in silico investigation showed a high folding stability of glyoxalase II toward its own reaction product glutathione both protonated and unprotonated. This study suggests that glyoxalase II, through a specific interaction of its catalytic site with target proteins, could be able to perform a rapid and specific protein S-glutathionylation using its natural substrate S-d-lactoylglutathione. SIGNIFICANCE This article reports for the first time a possible additional role of Glo2 that, after interacting with a target protein, is able to promote S-glutathionylation using its natural substrate SLG, a glutathione derived compound. In this perspective, Glo2 can play a new important regulatory role inS-glutathionylation, acquiring further significance in cellular post-translational modifications of proteins.

WOS:000477607500001; Objectives: Coenzyme Q(10), incorporated in DOPC lyposomes or naturally present in liver bovine mitochondria or in human blood plasma, was reacted with nitrogen dioxide (NO2)-N-center dot or with a (NO)-N-center dot/(NO2)-N-center dot mixture. Methods and Results: The reaction course was monitored by Electron Paramagnetic Resonance (EPR) spectroscopy and in all cases the formation of a di-tert-alkyl nitroxide was observed, deriving from the addition of (NO2)-N-center dot to one of the double bonds, most likely the terminal one, of the isoprenic chain. The rate constant for nitroxide formation was also determined by EPR spectroscopy and an initial rate of ca. 7 x 10(-8 )M s(-1) was obtained.

Both cancer and Alzheimer's disease (AD) are emerging as metabolic diseases in which aberrant/dysregulated glucose metabolism and bioenergetics occur, and play a key role in disease progression. Interestingly, an enhancement of glucose uptake, glycolysis and pentose phosphate pathway occurs in both cancer cells and amyloid-beta-resistant neurons in the early phase of AD. However, this metabolic shift has its adverse effects. One of them is the increase in methylglyoxal production, a physiological cytotoxic by-product of glucose catabolism. Methylglyoxal is mainly detoxified via cytosolic glyoxalase route comprising glyoxalase 1 and glyoxalase 2 with the production of S-D-lactoylglutathione and D-lactate as intermediate and end-product, respectively. Due to the existence of mitochondrial carriers and intramitochondrial glyoxalase 2 and D-lactate dehydrogenase, the transport and metabolism of both S-D-lactoylglutathione and D-lactate in mitochondria can contribute to methylglyoxal elimination, cellular antioxidant power and energy production. In this review, it is supposed that the different ability of cancer cells and AD neurons to metabolize methylglyoxal, S-D-lactoylglutathione and D-lactate scores cell fate, therefore being at the very crossroad of the "eternal youth" of cancer and the "premature death" of AD neurons. Understanding of these processes would help to elaborate novel metabolism-based therapies for cancer and AD treatment.

Loss-of-function mutations in the KRIT1 gene are associated with the pathogenesis of cerebral cavernous malformations (CCMs), a major cerebrovascular disease still awaiting therapies. Accumulating evidence demonstrates that KRIT1 plays an important role in major redox-sensitive mechanisms, including transcriptional pathways and autophagy, which play major roles in cellular homeostasis and defense against oxidative stress, raising the possibility that KRIT1 loss has pleiotropic effects on multiple redox-sensitive systems. Using previously established cellular models, we found that KRIT1 loss-of-function affects the glutathione (GSH) redox system, causing a significant decrease in total GSH levels and increase in oxidized glutathione disulfide (GSSG), with a consequent deficit in the GSH/GSSG redox ratio and GSH-mediated antioxidant capacity. Redox proteomic analyses showed that these effects are associated with increased S-glutathionylation of distinct proteins involved in adaptive responses to oxidative stress, including redox-sensitive chaperonins, metabolic enzymes, and cytoskeletal proteins, suggesting a novel molecular signature of KRIT1 loss-of-function. Besides providing further insights into the emerging pleiotropic functions of KRIT1, these findings point definitively to KRIT1 as a major player in redox biology, shedding new light on the mechanistic relationship between KRIT1 loss-of-function and enhanced cell sensitivity to oxidative stress, which may eventually lead to cellular dysfunctions and CCM disease pathogenesis.

Glyoxalase II (GlxII) is an antioxidant glutathione-dependent enzyme, which catalyzes the hydrolysis of S-d-lactoylglutathione to form d-lactic acid and glutathione (GSH). The last product is the most important thiol reducing agent present in all eukaryotic cells that have mitochondria and chloroplasts. It is generally known that GSH plays a crucial role not only in the cellular redox state but also in various cellular processes. One of them is protein S-glutathionylation, a process that can occur through an oxidation reaction of proteins' thiol groups by GSH. Changes in protein S-glutathionylation have been associated with a range of human diseases such as diabetes, cardiovascular and pulmonary diseases, neurodegenerative diseases and cancer. Within a major project aimed at elucidating the role of GlxII in the mechanism of S-glutathionylation, a reliable computational protocol consisting of a protein-protein docking approach followed by atomistic Molecular Dynamics (MD) simulations was developed and it was applied to the prediction of molecular associations between human GlxII (in the presence and absence of GSH) and some proteins that are known to be S-glutathionylated in vitro, such as actin, malate dehydrogenase (MDH) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The computational results show a high propensity of GlxII to interact with actin and MDH through its active site and a high stability of the GlxII-protein systems when GSH is present. Moreover, close proximities of GSH with actin and MDH cysteine residues have been found, suggesting that GlxII could be able to perform protein S-glutathionylation by using the GSH molecule present in its catalytic site.

Epigallocatechin-3-gallate (EGCG) is a polyphenolic catechin from green tea, well known for being bioactive in age-associated pathologies where oxidative stress plays a preeminent role. The activity of this molecule is however contrasted by its high chemical and metabolic instability that determines a poor concentration of the antioxidant within the biological system after administration. In order to protect the molecule and increase its delivery efficiency, we have encapsulated EGCG inside anionic liposomes made of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine and cholesteryl hemisuccinate. To maximize EGCG internalization, magnesium salt was added in the preparation. However stable nanodispersions suitable for drug delivery were obtained only after treatment with Poloxamer-407, a polyethylene-propylene glycol copolymer. The structural and morphological properties of the produced dispersion were studied by X-ray diffraction, which showed a multilamellar structure even after EGCG addition and an ordering effect of Poloxamer-407; Dynamic Light Scattering demonstrated serum stability of the liposomes. The characterization was completed by evaluating both encapsulation efficiency (100%, in the final formulation) and in vitro EGCG release. Since oxidative stress is involved in numerous retinal degenerative diseases, such as age-related macular degeneration, the ability of these liposomes to contrast H2O2-induced cell death was assessed in human retinal cells. Morphological changes at the subcellular level were analyzed by Transmission Electron Microscopy, which showed that mitochondria were better preserved in cells treated with liposomes then those treated with free EGCG. In conclusion, the results demonstrated that the produced formulation enhances the efficacy of EGCG under stress conditions, thus representing a potential formulation for the intracellular delivery of EGCG in diseases caused by oxidative damage.

Glutathione is considered the major non-protein low molecular weight modulator of redox processes and the most important thiol reducing agent of the cell. The biosynthesis of glutathione occurs in the cytosol from its constituent amino acids, but this tripeptide is also present in the most important cellular districts, such as mitochondria, nucleus, and endoplasmic reticulum, thus playing a central role in several metabolic pathways and cytoprotection mechanisms. Indeed, glutathione is involved in the modulation of various cellular processes and, not by chance, it is a ubiquitous determinant for redox signaling, xenobiotic detoxification, and regulation of cell cycle and death programs. The balance between its concentration and redox state is due to a complex series of interactions between biosynthesis, utilization, degradation, and transport. All these factors are of great importance to understand the significance of cellular redox balance and its relationship with physiological responses and pathological conditions. The purpose of this review is to give an overview on glutathione cellular compartmentalization. Information on its subcellular distribution provides a deeper understanding of glutathione-dependent processes and reflects the importance of compartmentalization in the regulation of specific cellular pathways. © 2018 BioFactors, 45(2):152-168, 2019.

Reactive oxygen species (ROS) production in the skin is among the highest compared to other organs, and a clear correlation exists between ROS production and skin aging. Many attempts are underway to reduce oxidative stress in the skin by topical treatment or supplementation with antioxidants/cosmeceuticals, and cultures of human dermal fibroblasts (HDF) are widely used for these studies. Here, we examined the influence of oxygen tension on cell aging in HDF and how this impacted ROS production, the enzymatic and nonenzymatic antioxidant response system, and the efficacy of this defense system in limiting DNA damage and in modulating gene expression of proteins involved in the extracellular matrix, linked to skin aging. We investigated a selection of parameters that represent and reflect the behavior of cellular responses to aging and oxygen tension. Serial passaging of HDF under normoxia (21%) and hypoxia (5%) leads to cell aging as confirmed by β-galactosidase activity, p16 expression, and proliferation rate. However, in HDF under 21% O2, markers of aging were significantly increased compared to those under 5% O2 at matched cell passages despite having lower levels of intracellular ROS and higher levels of CoQ10, total GSH, SOD1, SOD3, and mitochondrial superoxide anion. miRNA-181a, which is known to be upregulated in HDF senescence, was also analyzed, and indeed, its expression was significantly increased in old cells at 21% O2 compared to those at 5% O2. Upregulation of MMP1 and downregulation of COL1A1 along with increased DNA damage were also observed under 21% O2 vs 5% O2. The data highlight that chronic exposure to atmospheric 21% O2 is able to trigger hormetic adaptive responses in HDF that however fail, in the long term, to prevent cellular aging. This information could be useful in further investigating molecular mechanisms involved in adaptation of skin fibroblasts to oxidative stress and may provide useful hints in addressing antiaging strategies.

Reactive oxygen species not only cause damage but also have a physiological role in the protection against pathogens and in cell signalling. Mitochondrial nutrients, such as coenzyme Q10 and α-lipoic acid, beside their acknowledged antioxidant activities, show interesting features in relation to their redox state and consequent biological activity. In this study, we tested whether oral supplementation with 200 mg/day of coenzyme Q10 alone or in association with 200 mg/die of α-lipoic acid for 15 days on 16 healthy subjects was able to modulate the oxidative status into different compartments (plasma and cells), in basal condition and following an oxidative insult in peripheral blood lymphocytes exposed in vitro to H2O2. Data have shown that tested compounds produced antioxidant and bioenergetic effects improving oxidative status of the lipid compartment and mitochondrial functionality in peripheral blood lymphocytes. Simultaneously, an increased intracellular reactive oxygen species level was observed, although they did not lead to enhanced DNA oxidative damage. Coenzyme Q10 and α-lipoic acid produced beneficial effects also steering intracellular redox poise toward a pro-oxidant environment. In contrast with other antioxidant molecules, pro-oxidant activities of tested mitochondrial nutrients and consequent oxidant mediated signalling, could have important implications in promoting adaptive response to oxidative stress.

Objective: To evaluate the effectiveness of L-carnitine (LC) or L-acetyl-carnitine (LAC) or combined LC and LAC treatment in improving semen kinetic parameters and the total oxyradical scavenging capacity in semen. Design: Placebo-controlled, double-blind, randomized trial.Setting: Andrology unit, Department of Internal Medicine, Polytechnic University of Marche, Italy.Patient(s): Sixty infertile men, ages 20 to 40 years, with the following baseline sperm selection criteria: concentration > 20 × 10 6 / mL, sperm forward motility < 50 %, and normal sperm morphology > 30 %; 59 patients completed the study.Intervention(s): Patients underwent a double-blind therapy of LC 3 g / d, LAC 3 g / d, a combination of LC 2 g / d + LAC 1 g / d, or placebo. The study design was 1 month of run in, 6 months of therapy or placebo, and 3 months of follow-up evaluation.Main Outcome Measure(s): Variations in semen parameters used for patient selection, and variations in total oxyradical scavenging capacity of the seminal fluid.Result(s): Sperm cell motility (total and forward, including kinetic features determined by computer-assisted sperm analysis) increased in patients to whom LAC was administered both alone or in combination with LC; combined LC + LAC therapy led to a significant improvement of straight progressive velocity after 3 months. The total oxyradical scavenging capacity of the semen toward hydroxyl and peroxyl radicals also increased and was positively correlated with the improvement of kinetic features. Patients with lower baseline values of motility and total oxyradical scavenging capacity of the seminal fluid had a significantly higher probability of responding to the treatment.Conclusion(s): The administration of LC and LAC is effective in increasing sperm kinetic features in patients affected by idiopathic asthenozoospemia and improves the total oxyradical scavenging capacity of the seminal fluid in the same population (Fertil Steril ® 2005;84:662–71.©2005 by American Society for Reproductive Medicine.).

The health promoting effects of a regular consumption of strawberries deserve attention, and a direct or indirect antioxidant role of strawberry bioactive compounds is among the most probable mechanisms underlying their beneficial properties. In the present study, we evaluated the overall effects of a 2-week daily consumption of strawberries on plasma antioxidant status, membrane lipid susceptibility to ex vivo-induced oxidation, and erythrocyte and mononuclear cell resistance to oxidative damage in apparently healthy volunteers. After strawberry intake, a moderate increase in fasting plasma antioxidant capacity and vitamin C was observed, together with a significant increase in the lag phase preceding plasma lipid oxidation. A significantly enhanced resistance to oxidative hemolysis was confirmed in red blood cells, while no significant changes were found in the extent of their membrane lipid peroxidation. For the first time, increased intake of strawberries for only 2weeks was shown to be sufficient to attenuate mononuclear cell mortality after ex vivo exposure to a single acuteoxidative challenge, but the analysis of DNA oxidative damage gave conflicting results. These findings suggest that a regular consumption of strawberries may enhance body defences against oxidative challenges.

Objective Methylglyoxal (MG), a reactive carbonyl compound formed primarily from triose phosphates, appears to be involved in the molecular mechanisms of diabetes, end-stage renal disease and neurodegenerative diseases. Methylglyoxal exerts several biological activities. Among these it promotes advanced glycation end products (AGEs), which are crucial in pathogenesis of human disease. Previous studies have demonstrated that MG reacts with proteins and compositional modifications reflect loss of biological activity. The aim of the study was to investigate the effect of in vitro MG-induced glycation on human high density lipoprotein (HDL) and on the activity of the enzyme paraoxonase-1 (PON1). Methods HDL was incubated in the absence or in the presence of MG (0.2 mmol/L and 1.0 mmol/L) (MG-HDL) for different times (3, 6, 24 h) at 37 ° C. We evaluated apoprotein compositional changes, in both control and MG treated HDL, using intrinsic fluorescence of tryptophan and monitoring the decrease of free amino groups. Furthermore we evaluated fluorescent advanced glycation end products (Ex = 370 nm, Em = 440 nm) and the activity of HDL-paraoxonase. Results We demonstrated that human HDL is susceptible to glycation by MG (0.2 mmol/L and 1 mmol/L). The decrease of free amino groups and of intrinsic fluorescence of tryptophan demonstrates HDL apoprotein modifications in HDL incubated with MG. The compositional changes are associated with a significant increase in fluorescent advanced glycation end products and with a significant decrease of paraoxonase-1 enzyme activity associated with the HDL surface. Conclusions HDL-associated paraoxonase is responsible for the anti-inflammatory and anti-oxidative properties of HDL and detoxification against homocysteine-thiolactone. Therefore, modifications of apoprotein composition and the decrease of paraoxonase-1 activity in MG-treated HDL could affect the protective effect exerted by HDL against oxidative damage and could contribute to complications in patients affected by diseases associated with aging and oxidative stress.

Resveratrol (RES) is a stilbenoid polyphenol with interesting antitumor activity compromised by its poor solubility and bioavailability, thus, new approaches are necessary to improve its therapeutic effectiveness. In the present study, bovine serum albumin coated layered double hydroxide (LDH&ndash, BSA) was employed to encapsulate RES in order to overcome the above-mentioned usage limits. To evaluate the feasibility of neutral RES complexation with cationic LDH, we carried out molecular dynamics simulation in order to predict its structure and stability. In the supramolecular complex formed with LDH, RES disposes itself in the interlamellar region of LDH where it is stabilized by intermolecular interactions. The physico-chemical characteristics of the resulting nanocomplexes were studied by X-ray powder diffraction, transmission electron microscopy, and attenuated total reflection Fourier transform infrared spectroscopy. The encapsulation efficiency and drug release studies were also performed. The combined experimental and computational approach were highly effective in giving insight into the interaction mode of the neutral RES with the charged LDH. Finally, the nanohybrid&rsquo, s anticancer ability was evaluated in human lung cancer cell line (A549) resulting in higher activity with respect to bare RES. Overall, the results showed that the nanocomposites are suitable for biomedical applications as delivery agents of RES.

(1) Background: Hyperglycemia leads to several biochemical and physiological consequences, such as the generation of advanced glycation end products (AGEs) and reactive oxygen species (ROS), which are involved in the development of several human diseases. Intestinal cells are continuously exposed to pro-oxidants and lipid peroxidation products from ingested foods, and also to glyco-oxidative damage. It has been reported that free radical generation may be linked to the development of inflammation-related gastrointestinal diseases. (2) Methods: The effects of high glucose (HG) treatment (50 mM) were assessed in terms of free radical production, lipid peroxidation, and AGEs formation. Furthermore, the expression and the antiapoptotic and antioxidant activity of the paraoxonase-2 (PON2) enzyme in intestinal cells has been investigated. (3) Results: Caco-2 cells treated with media supplied with high glucose (HG) (50 mM) showed, with respect to physiological glucose concentration (25 mM), an increase in ROS production, lipid peroxidation, and AGEs formation. Moreover, a lower PON2 expression and activity in HG-treated cells was related to activation of the apoptotic pathways. (4) Conclusions: Our results demonstrated that high glucose concentrations triggered glyco-oxidative stress in intestinal cells, the downregulation of PON2 could result in a higher oxidative stress and might contribute to intestinal dysfunction.