Kaposi's sarcoma after T-cell costimulation blockade with abatacept in rheumatoid arthritis: a case report.

WHAT IS KNOWN AND OBJECTIVE: Kaposi's sarcoma (KS) is a malignant neoplasm caused by HHV-8, a pathogen that leads to endothelial cell transformation when host defences are weakened. CASE DESCRIPTION: Here we report the first case of KS during treatment with abatacept, a biologic agent targeting T-cell costimulation. The patient was a 64-year-old female with rheumatoid arthritis who developed multiple firm, purple-reddish nodules on the dorsal aspect of the right hand. Histological examination confirmed KS. WHAT IS NEW AND CONCLUSION: Although a direct causal relationship between KS development and abatacept treatment cannot be proved, we hypothesize a role for costimulation blockade.

Effects of moderate beer consumption on health and disease: A consensus document.

A large evidence-based review on the effects of a moderate consumption of beer on human health has been conducted by an international panel of experts who reached a full consensus on the present document. Low-moderate (up to 1 drink per day in women, up to 2 in men), non-bingeing beer consumption, reduces the risk of cardiovascular disease. This effect is similar to that of wine, at comparable alcohol amounts. Epidemiological studies suggest that moderate consumption of either beer or wine may confer greater cardiovascular protection than spirits. Although specific data on beer are not conclusive, observational studies seem to indicate that low-moderate alcohol consumption is associated with a reduced risk of developing neurodegenerative disease. There is no evidence that beer drinking is different from other types of alcoholic beverages in respect to risk for some cancers. Evidence consistently suggests a J-shaped relationship between alcohol consumption (including beer) and all-cause mortality, with lower risk for moderate alcohol consumers than for abstainers or heavy drinkers. Unless they are at high risk for alcohol-related cancers or alcohol dependency, there is no reason to discourage healthy adults who are already regular light-moderate beer consumers from continuing. Consumption of beer, at any dosage, is not recommended for children, adolescents, pregnant women, individuals at risk to develop alcoholism, those with cardiomyopathy, cardiac arrhythmias, depression, liver and pancreatic diseases, or anyone engaged in actions that require concentration, skill or coordination. In conclusion, although heavy and excessive beer consumption exerts deleterious effects on the human body, with increased disease risks on many organs and is associated to significant social problems such as addiction, accidents, violence and crime, data reported in this document show evidence for no harm of moderate beer consumption for major chronic conditions and some benefit against cardiovascular disease.

Unraveling the parahormetic mechanism underlying the health-protecting effects of grapeseed procyanidins.

Proanthocyanidins (PACs), the predominant constituents within Grape Seed Extract (GSE), are intricate compounds composed of interconnected flavan-3-ol units. Renowned for their health-affirming properties, PACs offer a shield against a spectrum of inflammation associated diseases, such as diabetes, obesity, degenerations and possibly cancer. While monomeric and dimeric PACs undergo some absorption within the gastrointestinal tract, their larger oligomeric and polymeric counterparts are not bioavailable. However, higher molecular weight PACs engage with the colonic microbiota, fostering the production of bioavailable metabolites that undergo metabolic processes, culminating in the emergence of bioactive agents capable of modulating physiological processes. Within this investigation, a GSE enriched with polymeric PACs was employed to explore in detail their impact. Through comprehensive analysis, the present study unequivocally verified the gastrointestinal-mediated transformation of medium to high molecular weight polymeric PACs, thereby establishing the bioaccessibility of a principal catabolite termed 5-(3',4'-dihydroxyphenyl)-γ-valerolactone (VL). Notably, our findings, encompassing cell biology, chemistry and proteomics, converge to the proposal of the notion of the capacity of VL to activate, upon oxidation to the corresponding quinone, the nuclear factor E2-related factor 2 (Nrf2) pathway-an intricate process that incites cellular defenses and mitigates stress-induced responses, such as a challenge brought by TNFα. This mechanistic paradigm seamlessly aligns with the concept of para-hormesis, ultimately orchestrating the resilience to stress and the preservation of cellular redox equilibrium and homeostasis as benchmarks of health.

Sudden progression from impaired glucose tolerance to type 2 diabetes after discontinuation of administration of anti-tumor necrosis factor-alpha antibody infliximab.

We present the case of a 45-year-old man with psoriasis and psoriatic arthritis and concomitant impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). In this patient, refractory to DMARD's, infliximab was started to control the arthritis. After achieving clinical remission of the disease, infliximab was discontinued and a 75 g- oral glucose tolerance test (OGTT) was performed. After the test, we observed a conversion from IFG/IGT glucose tolerance status to type 2 diabetes. No diet, lifestyle or therapy modifications were made during the observation period. Autoimmune diabetes was ruled out by serum antibodies determination and body weight remained constant, sustaining a protective role in infliximab in the worsening of glucose tolerance.

A dual attack on the peroxide bond. The common principle of peroxidatic cysteine or selenocysteine residues.

The (seleno)cysteine residues in some protein families react with hydroperoxides with rate constants far beyond those of fully dissociated low molecular weight thiol or selenol compounds. In case of the glutathione peroxidases, we could demonstrate that high rate constants are achieved by a proton transfer from the chalcogenol to a residue of the active site [Orian et al. Free Radic. Biol. Med. 87 (2015)]. We extended this study to three more protein families (OxyR, GAPDH and Prx). According to DFT calculations, a proton transfer from the active site chalcogenol to a residue within the active site is a prerequisite for both, creating a chalcogenolate that attacks one oxygen of the hydroperoxide substrate and combining the delocalized proton with the remaining OH or OR, respectively, to create an ideal leaving group. The "parking postions" of the delocalized proton differ between the protein families. It is the ring nitrogen of tryptophan in GPx, a histidine in GAPDH and OxyR and a threonine in Prx. The basic principle, however, is common to all four families of proteins. We, thus, conclude that the principle outlined in this investigation offers a convincing explanation for how a cysteine residue can become peroxidatic.

Chronobiology of acute pancreatitis in a single Italian centre.

OBJECTIVE: Seasonal variation may occur in many different diseases hence influencing awareness in clinical practice. This study aimed to establish seasonal variations of acute pancreatitis by using a validated chronobiological analysis. PATIENTS AND METHODS: All cases of acute pancreatitis consecutively observed in fifteen years, i.e., from January 2003 to December 2017, at St. Anna University Hospital of Ferrara, Italy, were included in this study. Accurate statistical and logistic regression analyses were applied to our database. RESULTS: A total number of 1883 consecutive cases of acute pancreatitis were observed. A significant peak was identified in the summer period (p=0.014). Patient stratification, according to age, showed that elderly people had an increased incidence of acute pancreatitis in autumn and summer (being the biliary stone disease the main cause, p=0.011) vs. other seasons (p=0.003). Mortality occurred more prominently in males vs. females, although the latter gender was more prone to acute pancreatitis (p=0.017). CONCLUSIONS: In a single centre of Northern East of Italy, we demonstrated that acute pancreatitis had a clear seasonal variation with a prominent incidence during summer. Various associated factors could contribute to this chronobiological pattern, including gender, age, and biliary stone disease.

Dual function of the selenoprotein PHGPx during sperm maturation.

The selenoprotein phospholipid hydroperoxide glutathione peroxidase (PHGPx) changes its physical characteristics and biological functions during sperm maturation. PHGPx exists as a soluble peroxidase in spermatids but persists in mature spermatozoa as an enzymatically inactive, oxidatively cross-linked, insoluble protein. In the midpiece of mature spermatozoa, PHGPx protein represents at least 50 percent of the capsule material that embeds the helix of mitochondria. The role of PHGPx as a structural protein may explain the mechanical instability of the mitochondrial midpiece that is observed in selenium deficiency.

[TNF-alpha and insulin-resistance: metabolic effects of in vivo therapeutic blockade]. / TNF-alfa e insulino-resistenza: effetti metabolici del blocco terapeutico in vivo.

Insulin resistance is a key pathophysiologic feature of obesity, type 2 diabetes mellitus and prediabetic states (impaired fasting glucose, impaired glucose tolerance). TNF-alpha, a proinflammatory cytokine, plays an important role in the pathogenesis of insulin resistance associated with inflammation during the course of rheumatic diseases. Therapies aimed at neutralizing TNF-alpha, such as the monoclonal antibody infliximab, represent a relatively new approach in the treatment of rheumatic diseases and allow to obtain significant results in terms of control of the inflammatory process. In this article we reviewed the scientific evidence published in the literature about a potential role of TNF-alpha blockade in improving insulin resistance in rheumatic patients without diabetes.

Costs of irritable bowel syndrome in European countries with universal healthcare coverage: a meta-analysis.

OBJECTIVE: To provide an overall estimate of the direct, indirect and total costs of irritable bowel syndrome (IBS) for the adult population of the European countries with universal healthcare coverage. MATERIALS AND METHODS: We searched MedLine and Scopus databases (up to September 2018) to identify the European studies that evaluated the economic impact of IBS. Mean annual direct, indirect and total per-capita IBS costs were estimated using random-effect single-group meta-analyses of continuous data. All analyses were stratified by payer category (governments, insurance, societal), and the results were expressed as summary mean and 95% CI. RESULTS: A total of 24 studies were included in the meta-analyses. Only two studies evaluated IBS costs in Italy. The pooled summary of direct IBS per-capita cost, obtained from 23 European datasets (n=15,157), was €1837/year (95% CI: 1480-2195), with large differences across payers (from €1183 to €3358, in countries with publicly-funded and insurance-based health systems, respectively). The mean indirect cost, extracted from 13 datasets (n=3978), was €2314/year (95% CI: 1811-2817), again with wide differences across payers. Finally, the meta-analysis estimating the total annual cost, based upon 11 European datasets (n=2757), yielded a summary estimate of €2889/year (95% CI: 2318-3460) per patient, ranging from €1602 (insurance-based health systems) to €3909 (studies adopting a societal perspective). CONCLUSIONS: Considering a conservative estimate of 2,736,700 Italian adults affected by the syndrome, the minimum costs due to IBS in Italy - likely underestimated - range from 6 to 8 billion euro per year. Given the substantial economic burden for patients, healthcare systems and society, IBS should be included among the priorities of the public health agenda.

The nuclear form of phospholipid hydroperoxide glutathione peroxidase is a protein thiol peroxidase contributing to sperm chromatin stability.

The selenoenzyme phospholipid hydroperoxide glutathione peroxidase (PHGPx) is regarded as the major molecular target of selenodeficiency in rodents, accounting for most of the histopathological and structural abnormalities of testicular tissue and male germ cells. PHGPx exists as a cytosolic form, mitochondrial form, and nuclear form (nPHGPx) predominantly expressed in late spermatids and spermatozoa. Here, we demonstrate that mice with a targeted deletion of the nPHGPx gene were, unlike mice with the full knockout (KO) of PHGPx, not only viable but also, surprisingly, fully fertile. While both morphological analysis of testis and epididymis and sperm parameter measurements did not show any apparent abnormality, toluidine blue and acridine orange stainings of spermatozoa indicated defective chromatin condensation in the KO sperm isolated from the caput epididymis. Furthermore, upon drying and hydrating, KO sperm exhibited a significant proportion of morphologically abnormal heads. Monobromobimane labeling and protein-free thiol titration revealed significantly less extensive oxidation in the cauda epididymis when compared to that in the wild type. We conclude that nPHGPx, by acting as a protein thiol peroxidase in vivo, contributes to the structural stability of sperm chromatin.

The selenoenzyme phospholipid hydroperoxide glutathione peroxidase.

The reduction of membrane-bound hydroperoxides is a major factor acting against lipid peroxidation in living systems. This paper presents the characterization of the previously described 'peroxidation-inhibiting protein' as a 'phospholipid hydroperoxide glutathione peroxidase'. The enzyme is a monomer of 23 kDa (SDS-polyacrylamide gel electrophoresis). It contains one gatom Se/22 000 g protein. Se is in the selenol form, as indicated by the inactivation experiments in the presence of iodoacetate under reducing conditions. The glutathione peroxidase activity is essentially the same on different phospholipids enzymatically hydroperoxidized by the use of soybean lipoxidase (EC 1.13.11.12) in the presence of deoxycholate. The kinetic data are compatible with a tert-uni ping-pong mechanism, as in the case of the 'classical' glutathione peroxidase (EC 1.11.1.9). The second-order rate constants (K1) for the reaction of the enzyme with the hydroperoxide substrates indicate that, while H2O2 is reduced faster by the glutathione peroxidase, linoleic acid hydroperoxide is reduced faster by the present enzyme. Moreover, the phospholipid hydroperoxides are reduced only by the latter. The dramatic stimulation exerted by Triton X-100 on the reduction of the phospholipid hydroperoxides suggests that this enzyme has an 'interfacial' character. The similarity of amino acid composition, Se content and kinetic mechanism, relative to the difference in substrate specificity, indicates that the two enzymes 'classical' glutathione peroxidase and phospholipid hydroperoxide glutathione peroxidase are in some way related. The latter is apparently specialized for lipophylic, interfacial substrates.

Phospholipid hydroperoxide glutathione peroxidase in various mouse organs during selenium deficiency and repletion.

An assay for the determination of the newly discovered selenoenzyme, phospholipid hydroperoxide glutathione peroxidase (PH-GPx) in biological material is described. Dietary selenium deficiency and repletion was used as a tool in order to modify this enzyme activity in various mouse organs and to compare it to the activity of the 'classical' selenium-dependent glutathione peroxidase (GPx) (EC 1.11.1.9). A semipurified diet containing less than 12 ppb Se was used for depletion. Controls received this diet supplemented with 500 ppb Se in the form of Na2SeO3. The results showed that a rapid loss of GPx activity occurred in liver, kidney and lungs of selenium-deficient mice which reached undetectable levels within 130 days. In the heart, about 24% of control GPx activity was still present. In contrast, PH-GPx activity was more slowly depleted by Se deficiency and resulted in residual activities ranging from 30 to 70% in the different organs even after 250 days of depletion. In repletion experiments with a single application of 10 or 500 micrograms/kg Se, only the high dose restored either enzyme activity. The data demonstrate that the need for selenium of the two glutathione peroxidases is different. A markedly distinct organ distribution of both enzymes suggests that the heart may be the organ more sensitive to oxidative stress.

Purification and characterization of phospholipid hydroperoxide glutathione peroxidase from rat testis mitochondrial membranes.

The selenoenzyme phospholipid hydroperoxide glutathione peroxidase (PHGPx) is highly expressed in rat testis, where it is under gonadotropin control. In this organ a relevant PHGPx activity is strongly linked to mitochondria of cells undergoing differentiation to spermatozoa. This prompted a study on the possible difference between the soluble and the mitochondrial enzyme and the nature of the binding. The mitochondrial PHGPx activity could be solubilized by detergents or by the combined action of mild detergent treatment and ionic strength, thus suggesting an electrostatic binding of the protein to the inner surfaces of the organelle. The same chromatographic purification procedures were applied to cytosolic and membrane bound PHGPx, without revealing any significant difference between the two forms. Moreover, the electrophoretic mobility, the reactivity to antibodies and the fragmentation patterns also suggested the identity of the two forms of testis PHGPx. Eventually, testis cytosolic and membrane bound PHGPx showed the same substrate specificity for both peroxidic and thiol substrates. On the other hand, a complex behaviour on hydrophobic interaction chromatography, compatible with multiple forms of the enzyme, and with a different tertiary structure of the major peaks was observed for soluble and mitochondrial PHGPx. Accordingly, two-dimensional electrophoresis followed by immunostaining with monoclonal antibodies, showed the presence of multiple isoforms with a different pattern between the soluble and the mitochondrial enzyme. These differences are not accounted for by glycosylation or a different degree of phosphorylation of tyrosines. In both enzymes, indeed, no glycosylation was detected and no more than 10% of PHGPx molecules were shown to contain a phosphotyrosine residue.

Formation of alpha-tocopherol radical and recycling of alpha-tocopherol by ascorbate during peroxidation of phosphatidylcholine liposomes. An electron paramagnetic resonance study.

The events accompanying the inhibitory effect of alpha-tocopherol and/or ascorbate on the peroxidation of soybean L-alpha-phosphatidylcholine liposomes, which are an accepted model of biological membranes, were investigated by electron paramagnetic resonance, optical and polarographic methods. The presence of alpha-tocopherol radical in the concentration range 10(-8)-10(-7) M was detected from its EPR spectrum during the peroxidation of liposomes, catalysed by the Fe3+-triethylenetatramine complex. The alpha-tocopherol radical, generated in the phosphatidylcholine bilayer, is accessible to ascorbic acid, present in the aqueous phase at physiological concentrations. Ascorbic acid regenerates from it the alpha-tocopherol itself. A kinetic rate constant of about 2 X 10(5) M-1 X s-1 was estimated from the reaction as it occurs under the adopted experimental conditions. The scavenging effect of alpha-tocopherol on lipid peroxidation is maintained as long a ascorbic acid is present.

Glutathione depletion increases chemiluminescence emission and lipid peroxidation in the heart.

Diamide, CDNB and phorone were used to deplete glutathione in retrogradely perfused rat hearts. Following glutathione depletion the spontaneous chemiluminescence increased by 70%, irrespective of the agent used. The glutathione depletion and the chemiluminescence emission were associated to an increase of malondialdehyde content in the heart, as determined by HPLC. Under these conditions the heart function was impaired and histological examination showed a coagulative myocytolysis, a pattern already described in human and experimental pathology, where a key role is attributed to a Ca2+ homeostasis impairment.

Phospholipid hydroperoxide glutathione peroxidase: specific activity in tissues of rats of different age and comparison with other glutathione peroxidases.

The tissue distribution of phospholipid hydroperoxide glutathione peroxidase (PHGPX) was studied in rats of different ages. In the same samples the activities of Se-dependent glutathione peroxidase (GPX), and non-Se-dependent glutathione peroxidase (non Se-GPX) were also determined using specific substrates for each enzyme. Enzymatically generated phospholipid hydroperoxides were used as substrate for PHGPX, hydrogen peroxide for GPX, and cumene hydroperoxide for non-Se-GPX (after correction for the activity of GPX on this substrate). PHGPX specific activity in different organs is as follows: liver = kidney greater than heart = lung = brain greater than muscle. Furthermore, this activity is reasonably constant in different age groups, with a lower specific activity observed only in kidney and liver of young animals. GPX activity is expressed as follows: liver greater than kidney greater than heart greater than lung greater than brain = muscle, and substantial age-dependent differences have been observed (adult greater than old greater than young). Non-Se-GPX activity was present in significant amount only in liver greater than lung greater than heart and only in adult animals. These results suggest a tissue- and age-specific expression of different peroxidases.

Purification from pig liver of a protein which protects liposomes and biomembranes from peroxidative degradation and exhibits glutathione peroxidase activity on phosphatidylcholine hydroperoxides.

The cell sap from pig liver contains a protein which protects phosphatidylcholine liposomes and biomembranes from peroxidative degradation in the presence of glutathione. The activity of this protein has been assayed by measuring the inhibition of aged phosphatidylcholine liposome peroxidation induced by the Fe3+-triethylenetetramine complex. The peroxidation-inhibiting protein from pig liver has been purified 585-fold to homogeneity with overall recovery of activity of 12%. (NH4)2SO4 precipitation, ion-exchange chromatography on DEAE-Sepharose CL-6B and CM23-cellulose, affinity chromatography on glutathione-bromosulfophthalein-Sepharose and gel filtration on Sephadex G-50 were used. Gel filtration and SDS- polyacrylamide gel electrophoresis indicated a molecular weight of approximately 20 000. The protein inhibited peroxidation by Fe3+-triethylenetetramine following a 15 min preincubation of phosphatidylcholine liposomes in the presence of 5mM glutathione or 2-mercapthoethanol. The pure protein exhibited glutathione peroxidase activity on hydroperoxide groups of phosphatidylcholine and on cumene and t-butyl hydroperoxides, with specific activities of 2.2, 3.8 and 0.9 mumol/min per mg protein, respectively. The protein appears to be distinct from the selenoenzyme glutathione peroxidase and from any known glutathione S-transferase. The peroxidation was studied also with fresh phosphatidylcholine liposomes and was induced in this case by Fe-ascorbate. To obtain protection by the peroxidation-inhibiting protein and glutathione, preincubation was not necessary, but alpha-tocopherol, incorporated in the liposomes in the molar ratio 1:250 to phosphatidylcholine, was required. Lipid peroxidation of rat liver mitoplasts and microsomes was blocked when these preparations were incubated in the peroxidizing mixture in the presence of peroxidation-inhibiting protein and glutathione. The protection from Fe3+-triethylenetetramine-induced peroxidation is related apparently to reduction of hydroperoxide groups in polyunsaturated fatty acid residues of phospholipids and to inhibition of free radicals formation by chain branching. Protection from the Fe-ascorbate-induced peroxidation is apparently attributable to the same mechanism. However, the requirement of alpha-tocopherol for protection in the Fe-ascorbate-induced peroxidation suggests that the cooperation of a free-radical scavenger is necessary. It is probable that the glutathione peroxidase activity is involved also in the glutathione-dependent protection exhibited by the protein on lipid peroxidation of biomembranes.

Correlation between hydroperoxide-induced chemiluminescence of the heart and its function.

The isolated perfused rat heart emits a spontaneous ultraweak chemiluminescence. When the perfusion is stopped, light emission decreases, indicating the dependency of this phenomenon on aerobic metabolism. Emitted chemiluminescence was markedly enhanced following perfusion with 0.05 mM H2O2 or cumene hydroperoxide or tert-butyl hydroperoxide; substitution of O2 for N2 in the gassing mixture of the perfusion media significantly lowered photon emission. Lipid peroxidation, which is known to be associated with chemiluminescence, was evaluated by HPLC analysis of peroxidized and unperoxidized heart phosphatidylcholines. During hydroperoxide perfusion, coronary flow and heart rate progressively decreased, while lactic dehydrogenase was released after complete cardiac arrest. The resultant morphology of this damage corresponds to the so-called 'stone heart', a pattern already described in both human and experimental pathology.

Enzymatic reduction of phospholipid and cholesterol hydroperoxides in artificial bilayers and lipoproteins.

Lipid hydroperoxides (LOOHs) in various lipid assemblies are shown to be efficiently reduced and deactivated by phospholipid hydroperoxide glutathione peroxidase (PHGPX), the second selenoperoxidase to be identified and characterized. Coupled spectrophotometric analyses in the presence of NADPH, glutathione (GSH), glutathione reductase and Triton X-100 indicated that photochemically generated LOOHs in small unilamellar liposomes are substrates for PHGPX, but not for the classical glutathione peroxidase (GPX). PHGPX was found to be reactive with cholesterol hydroperoxides as well as phospholipid hydroperoxides. Kinetic iodometric analyses during GSH/PHGPX treatment of photoperoxidized liposomes indicated a rapid decay of total LOOH to a residual level of 35-40%; addition of Triton X-100 allowed the reaction to go to completion. The non-reactive LOOHs in intact liposomes were shown to be inaccessible groups on the inner membrane face. In the presence of iron and ascorbate, photoperoxidized liposomes underwent a burst of thiobarbituric acid-detectable lipid peroxidation which could be inhibited by prior GSH/PHGPX treatment, but not by GSH/GPX treatment. Additional experiments indicated that hydroperoxides of phosphatidylcholine, cholesterol and cholesteryl esters in low-density lipoprotein are also good substrates for PHGPX. An important role of PHGPX in cellular detoxification of a wide variety of LOOHs in membranes and internalized lipoproteins is suggested from these findings.