Non-steroidal anti-inflammatory drugs activate NADPH oxidase in adipocytes and raise the H2O2 pool to prevent cAMP-stimulated protein kinase a activation and inhibit lipolysis. BMC Biochem. 2013;14:13. [PMID: 23718778 DOI: 10.1186/1471-2091-14-13]

Cellular Compartmentalization, Glutathione Transport and Its Relevance in Some Pathologies

Reduced glutathione (GSH) is the most abundant non-protein endogenous thiol. It is a ubiquitous molecule produced in most organs, but its synthesis is predominantly in the liver, the tissue in charge of storing and distributing it. GSH is involved in the detoxification of free radicals, peroxides and xenobiotics (drugs, pollutants, carcinogens, etc.), protects biological membranes from lipid peroxidation, and is an important regulator of cell homeostasis, since it participates in signaling redox, regulation of the synthesis and degradation of proteins (S-glutathionylation), signal transduction, various apoptotic processes, gene expression, cell proliferation, DNA and RNA synthesis, etc. GSH transport is a vital step in cellular homeostasis supported by the liver through providing extrahepatic organs (such as the kidney, lung, intestine, and brain, among others) with the said antioxidant. The wide range of functions within the cell in which glutathione is involved shows that glutathione’s role in cellular homeostasis goes beyond being a simple antioxidant agent; therefore, the importance of this tripeptide needs to be reassessed from a broader metabolic perspective.

Inhibition of cyclooxygenase and EP3 receptor improved long term potentiation in a rat organotypic hippocampal model of repeated blast traumatic brain injury

Blast-induced traumatic brain injury (bTBI) is a health concern in military service members who are exposed to multiple blasts throughout their training and deployment. Our group has previously reported decreased long term potentiation (LTP) following repeated bTBI in a rat organotypic hippocampal slice culture (OHSC) model. In this study, we investigated changes in inflammatory markers like cyclooxygenase (COX) and tested the efficacy of COX or prostaglandin EP3 receptor (EP3R) inhibitors in attenuating LTP deficits. Expression of COX-2 was increased 48 h following repeated injury, whereas COX-1 expression was unchanged. EP3R expression was upregulated, and cyclic adenosine monophosphate (cAMP) concentration was decreased after repeated blast exposure. Post-traumatic LTP deficits improved after treatment with a COX-1 specific inhibitor, SC-560, a COX-2 specific inhibitor, rofecoxib, a pan-COX inhibitor, ibuprofen, or an EP3R inhibitor, L-798,106. Delayed treatment with ibuprofen and L-798,106 also prevented LTP deficits. These findings suggest that bTBI induced neuroinflammation may be responsible for some functional deficits that we have observed in injured OHSCs. Additionally, COX and EP3R inhibition may be viable therapeutic strategies to reduce neurophysiological deficits after repeated bTBI.

Modulation of Reactive Oxygen Species Homeostasis as a Pleiotropic Effect of Commonly Used Drugs

Age-associated diseases represent a growing burden for global health systems in our aging society. Consequently, we urgently need innovative strategies to counteract these pathological disturbances. Overwhelming generation of reactive oxygen species (ROS) is associated with age-related damage, leading to cellular dysfunction and, ultimately, diseases. However, low-dose ROS act as crucial signaling molecules and inducers of a vaccination-like response to boost antioxidant defense mechanisms, known as mitohormesis. Consequently, modulation of ROS homeostasis by nutrition, exercise, or pharmacological interventions is critical in aging. Numerous nutrients and approved drugs exhibit pleiotropic effects on ROS homeostasis. In the current review, we provide an overview of drugs affecting ROS generation and ROS detoxification and evaluate the potential of these effects to counteract the development and progression of age-related diseases. In case of inflammation-related dysfunctions, cardiovascular- and neurodegenerative diseases, it might be essential to strengthen antioxidant defense mechanisms in advance by low ROS level rises to boost the individual ROS defense mechanisms. In contrast, induction of overwhelming ROS production might be helpful to fight pathogens and kill cancer cells. While we outline the potential of ROS manipulation to counteract age-related dysfunction and diseases, we also raise the question about the proper intervention time and dosage.

Niacin Status Indicators and Their Relationship with Metabolic Parameters in Dairy Cows during Early Lactation

Simple Summary

The active forms of niacin that represent niacin status are nicotinamide adenine dinucleotide (NAD), nicotinamide adenine dinucleotide phosphate (NADP) and the NAD:NADP ratio. Previous studies have shown metabolic changes in the function of niacin form and dose, but it has not been determined whether there are changes in the function of active form of niacin that indicate the vitamin status in the body. In this study, we examined differences in NAD, NADP and NAD:NADP concentration in blood and their relationship with metabolic parameters in cows receiving and not receiving additional niacin in food. We concluded that NAD and NADP are good indicators of the ability of an additional niacin source to create functional cofactors due to their concentration changes, while the NAD:NADP ratio is a good indicator of the biological effects of additional niacin due to correlation with many metabolites.

Abstract

Previous experimental models on cows have examined the difference in the metabolic adaptation in cows after niacin administration, without identifying the most important mediators between niacin administration and its biological effects, namely active forms of niacin. All tissues in the body convert absorbed niacin into its main metabolically active form, the coenzyme nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). The aim of this study was to determine the influence of niacin administration in periparturient period on NAD, NADP and the NAD:NADP ratio and to determine relationship between these indicators of an active form of niacin with metabolic parameters in cow blood. The study included 90 healthy cows: 45 cows receiving niacin and 45 cows were negative control. The niacin group was treated with nicotinic acid for two weeks before, as well as two weeks after parturition. Nicotinic acid was applied per os with feed. In cows receiving niacin, there was a significantly higher concentration of NAD and NADP, but the NAD:NADP ratio did not differ compared with control. All three indicators were able to separate cows who received and who did not receive additional niacin. NAD and NADP are good indicators of the availability of niacin from additional sources. The NAD:NADP ratio is a good indicator of the biological effect of applied niacin on metabolites in cows due to its correlation with a number of metabolites: positive correlation with glucose, insulin, glucose to insulin ratio and the revised quantitative insulin sensitivity check index (RQUICKIBHB) of insulin resistance, triglycerides and cholesterol, and a negative correlation with nonesterified fatty acid (NEFA), beta hydroxybutyrate (BHB), gamma-glutamyltranspherase (GGT) and urea in cows receiving niacin. The same amount of added niacin in feed can produce different concentrations of NAD, NADP and NAD:NADP in the blood, and this was not related to their concentration before the addition of niacin. The change in the concentration of the active form of niacin (NAD, NADP and NAD:NADP) further correlates with the concentration of metabolic parameters, which indicates that the intensity of the biological effect of additional niacin can be accurately determined only if we know the concentrations of its active forms in blood. Under basal conditions (without additional niacin), active forms of niacin that already exist in the blood do not show significant correlations with metabolic parameters.

Brain damage induced by contaminants released in a hospital from Mexico: Evaluation of swimming behavior, oxidative stress, and acetylcholinesterase in zebrafish (Danio rerio)

Several studies have indicated that hospital effluents can produce genotoxic and mutagenic effects, cytotoxicity, hematological and histological alterations, embryotoxicity, and oxidative stress in diverse water organisms, but research on the neurotoxic effects hospital wastewater materials can generate in fish is still scarce. To fill the above-described knowledge gap, this study aimed to determine whether the exposure of adult zebrafish (Danio rerio) to several proportions (0.1%, 2.5%, 3.5%) of a hospital effluent can disrupt behavior or impair redox status and acetylcholinesterase content in the brain. After 96 h of exposure to the effluent, we observed a decrease in total distance traveled and an increase in frozen time compared to the control group. Moreover, we also observed a significant increase in the levels of reactive oxygen species in the brains of the fish, especially in hydroperoxide and protein carbonyl content, relative to the control group. Our results also demonstrated that hospital effluents significantly inhibited the activity of the AChE enzyme in the brains of the fish. Our Pearson correlation demonstrated that the response to acetylcholinesterase at the lowest proportions (0.1% and 2.5%) is positively related to the oxidative stress response and the behavioral changes observed. The cohort of our studies demonstrated that the exposure of adult zebrafish to a hospital effluent induced oxidative stress and decreased acetylcholinesterase activity in the brain of these freshwater organisms, which can lead to alterations in their behavior.

Redox Regulation of Lipid Mobilization in Adipose Tissues

Lipid mobilization in adipose tissues, which includes lipogenesis and lipolysis, is a paramount process in regulating systemic energy metabolism. Reactive oxygen and nitrogen species (ROS and RNS) are byproducts of cellular metabolism that exert signaling functions in several cellular processes, including lipolysis and lipogenesis. During lipolysis, the adipose tissue generates ROS and RNS and thus requires a robust antioxidant response to maintain tight regulation of redox signaling. This review will discuss the production of ROS and RNS within the adipose tissue, their role in regulating lipolysis and lipogenesis, and the implications of antioxidants on lipid mobilization.

Paracetamol (acetaminophen): A familiar drug with an unexplained mechanism of action

Paracetamol (acetaminophen) is undoubtedly one of the most widely used drugs worldwide. As an over-the-counter medication, paracetamol is the standard and first-line treatment for fever and acute pain and is believed to remain so for many years to come. Despite being in clinical use for over a century, the precise mechanism of action of this familiar drug remains a mystery. The oldest and most prevailing theory on the mechanism of analgesic and antipyretic actions of paracetamol relates to the inhibition of CNS cyclooxygenase (COX) enzyme activities, with conflicting views on the COX isoenzyme/variant targeted by paracetamol and on the nature of the molecular interactions with these enzymes. Paracetamol has been proposed to selectively inhibit COX-2 by working as a reducing agent, despite the fact that in vitro screens demonstrate low potency on the inhibition of COX-1 and COX-2. In vivo data from COX-1 transgenic mice suggest that paracetamol works through inhibition of a COX-1 variant enzyme to mediate its analgesic and particularly thermoregulatory actions (antipyresis and hypothermia). A separate line of research provides evidence on potentiation of the descending inhibitory serotonergic pathway to mediate the analgesic action of paracetamol, but with no evidence of binding to serotonergic molecules. AM404 as a metabolite for paracetamol has been proposed to activate the endocannabinoid and the transient receptor potential vanilloid-1 (TRPV1) systems. The current review gives an update and in some cases challenges the different theories on the pharmacology of paracetamol and raises questions on some of the inadequately explored actions of paracetamol. List of Abbreviations: AM404, N-(4-hydroxyphenyl)-arachidonamide; CB1R, Cannabinoid receptor-1; Cmax, Maximum concentration; CNS, Central nervous system; COX, Cyclooxygenase; CSF, Cerebrospinal fluid; ED50, 50% of maximal effective dose; FAAH, Fatty acid amidohydrolase; IC50, 50% of the maximal inhibitor concentration; LPS, Lipopolysaccharide; NSAIDs, Non-steroidal anti-inflammatory drugs; PGE2, Prostaglandin E2; TRPV1, Transient receptor potential vanilloid-1.

A reactive oxygen species-responsive antioxidant nanotherapy for the treatment of drug-induced tissue and organ injury

Drug-induced tissue injury has become a growing public health problem. Gastrointestinal injury and liver dysfunction are the most common side effects related to drug therapies, resulting in high morbidity and mortality in recent years. The overproduction of reactive oxygen species (ROS) is critically involved in the pathogenesis of drug-induced tissue injury. Consequently, antioxidant therapy represents a very promising strategy for the treatment of drug-induced tissue injury. Herein, a multifunctional antioxidant nanotherapy (TON) is engineered from a cyclodextrin-derived ROS-responsive material and a radical scavenger tempol, and is capable of eliminating a broad spectrum of ROS. After oral administration, TON can passively accumulate in the inflamed gastrointestinal tissues in mice with indomethacin-induced gastrointestinal injury. Correspondingly, TON shows superior efficacy in two representative murine models of indomethacin-induced gastrointestinal injury and acetaminophen-induced hepatic injury via attenuating oxidative stress and mitigating inflammatory responses. Additionally, preliminary in vitro and in vivo experiments demonstrate the good safety profile of TON. Consequently, the ROS-responsive antioxidant nanotherapy TON is promising for the treatment of drug-induced tissue and organ injury.

Regulation of Metabolic Processes by Hydrogen Peroxide Generated by NADPH Oxidases

Hydrogen peroxide (H2O2) is an important oxidizing molecule that regulates the metabolisms of aerobic organisms. Redox signaling comprises physiological oxidative stress (eustress), while excessive oxidative stress causes damage to molecules. The main enzymatic generators of H2O2 are nicotinamide adenine dinucleotide phosphate oxidases or NADPH oxidases (NOXs) and mitochondrial respiratory chains, as well as various oxidases. The NOX family is constituted of seven enzyme isoforms that produce a superoxide anion (O2−), which can be converted to H2O2 by superoxide dismutase or spontaneously. H2O2 passes through the membranes by some aquaporins (AQPs), known as peroxyporins. It diffuses through cells and tissues to initiate cellular effects, such as proliferation, the recruitment of immune cells, and cell shape changes. Therefore, it has been proposed that H2O2 has the same importance as Ca2+ or adenosine triphosphate (ATP) to act as modulators in signaling and the metabolism. The present overview focuses on the metabolic processes of liver and adipose tissue, regulated by the H2O2 generated by NOXs.

Oxidative stress resulting from the removal of endogenous catalase induces obesity by promoting hyperplasia and hypertrophy of white adipocytes

Obesity is regarded as an abnormal expansion and excessive accumulation of fat mass in white adipose tissue. The involvement of oxidative stress in the development of obesity is still unclear. Although mainly present in peroxisomes, catalase scavenges intracellular H₂O₂ at toxic levels. Therefore, we used catalase-knockout (CKO) mice to elucidate the involvement of excessive H₂O₂ in the development of obesity. CKO mice with C57BL/6J background gained more weight with higher body fat mass with age than age-matched wild-type (WT) mice fed with either chow or high-fat diets. This phenomenon was attenuated by concomitant treatment with the antioxidants, melatonin or N-acetyl cysteine. Moreover, CKO mouse embryonic fibroblasts (MEFs) appeared to differentiate to adipocytes more easily than WT MEFs, showing increased H₂O₂ concentrations. Using 3T3-L1-derived adipocytes transfected with catalase-small interfering RNA, we confirmed that a more prominent lipogenesis occurred in catalase-deficient cells than in WT cells. Catalase-deficient adipocytes presented increased nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) expression but decreased adenosine monophosphate-activated protein kinase (AMPK) expression. Treatment with a NOX4 inhibitor or AMPK activator rescued the propensity for obesity of CKO mice. These findings suggest that excessive H₂O₂ and related oxidative stress increase body fat mass via both adipogenesis and lipogenesis. Manipulating NOX4 and AMPK in white adipocytes may be a therapeutic tool against obesity augmented by oxidative stress.

Aquaporin 8 is involved in H2 O2 -mediated differential regulation of metabolic signaling by α1 - and β-adrenoceptors in hepatocytes

Reactive oxygen species participate in regulating intracellular signaling pathways. Herein, we investigated the reported opposite effects of hydrogen peroxide (H₂ O₂ ) on metabolic signaling mediated by activated α₁ - and β-adrenoceptors (ARs) in hepatocytes. In isolated rat hepatocytes, stimulation of α₁ -AR increases H₂ O₂ production via NADPH oxidase 2 (NOX2) activation. We find that the H₂ O₂ thus produced is essential for α₁ -AR-mediated activation of the classical hepatic glycogenolytic, gluconeogenic, and ureagenic responses. However, H₂ O₂ inhibits β-AR-mediated activation of these metabolic responses. We show that H₂ O₂ mediates its effects on α₁ -AR and β-AR by permeating cells through aquaporin 8 (AQP8) channels and promoting Ca²⁺ mobilization. Thus, our findings reveal a novel NOX2-H₂ O₂ -AQP8-Ca²⁺ signaling cascade acting downstream of α₁ -AR in hepatocytes, which, by negatively regulating β-AR signaling, establishes negative crosstalk between the two pathways.

Soybean Peroxidase Catalyzed Decoloration of Acid Azo Dyes

BACKGROUND

Some industrial manufacturing processes generate and release dyes as water pollutants, many of which are toxic and hazardous materials. There is a need for milder, greener methods for dye treatment.

OBJECTIVES

The objective of the present study was to investigate and optimize azo dye decoloration by a crude soybean peroxidase (SBP), based on two dyes that have widespread industrial use, but that differ greatly in structural complexity, Acid Black 2 and Acid Orange 7, and to investigate the effects of specific parameters on the removal process.

METHODS

Batch reactors were used to remove 95% of the dyes' color and to produce substantial precipitates.

RESULTS

The optimum pH for enzymatic decoloration of Acid Black 2 was in the acidic region, pH 4.4, and that of Acid Orange 7 occurred under neutral conditions, pH 6.9. The minimum enzyme activity needed for sufficient removal was 1.2 U/mL for both dyes at 0.5 mM. The minimum molar hydrogen peroxide/substrate ratio was 3 for Acid Orange 7 and 2.5 for Acid Black 2 to achieve approximately 95% removal. First-order fitting of progress curve data collected under the respective optimum conditions gave half-lives of 23.9 and 28.9 minutes for Acid Orange 7 and Acid Black 2, respectively.

CONCLUSIONS

The feasibility of SBP-catalyzed treatment of industrial dyes Acid Black 2 and/or Acid Orange 7, or dyes that resemble them, as they might occur in industrial effluents, was successfully demonstrated.

COMPETING INTERESTS

The authors declare no competing financial interests.

Inhibition of lipolysis: A novel explanation for the hypothermic actions of acetaminophen in non-febrile rodents

Acetaminophen is both widely used to treat children with fever and is also responsible for thousands being hospitalised annually. Historically the antipyretic actions of acetaminophen were attributed to the inhibition of cyclooxygenase (COX-1/2) enzymes and more recently a novel COX-1 variant (COX-3) located in the brain. However, the evidence for acetaminophen-mediated COX inhibition remains contentious. This study assesses the impact of acetaminophen and other putative COX-3 inhibitors on the release of fatty acids during lipolysis as an alternative mechanism by which antipyretics can reduce body temperature during fever. 3T3-L1 adipocytes, primary brown adipocytes and isolated mitochondria were exposed to COX-3 inhibitors and lipolysis and mitochondrial electron transport chain function assessed. Acetaminophen, aminopyrine and antipyrine at 1-10 mM caused a significant decrease (up to 70%; P < 0.01, from control) in lipolysis within 1, 3 and 24 h without affecting cell viability. The inhibition was observed regardless of where along its signalling pathway lipolysis was stimulated. All three compounds were found to significantly attenuate mitochondrial function by up to 30% for complex I and 40% for complex II (P < 0.01, from control). These novel observations combined with the known limited inhibition of the COX enzymes by acetaminophen suggest both the antipyretic and hypothermia induced by acetaminophen and related compounds could be attributed to the direct inhibition of lipolysis and mitochondrial function, rather than cyclooxygenase inhibition centrally. Further these observations could provide new drug targets for reducing fever with the added bonus of fewer individuals being hospitalized by accidental acetaminophen overdose.

Immunometabolism and Pulmonary Infections: Implications for Protective Immune Responses and Host-Directed Therapies

The biology and clinical efficacy of immune cells from patients with infectious diseases or cancer are associated with metabolic programming. Host immune- and stromal-cell genetic and epigenetic signatures in response to the invading pathogen shape disease pathophysiology and disease outcomes. Directly linked to the immunometabolic axis is the role of the host microbiome, which is also discussed here in the context of productive immune responses to lung infections. We also present host-directed therapies (HDT) as a clinically viable strategy to refocus dysregulated immunometabolism in patients with infectious diseases, which requires validation in early phase clinical trials as adjuncts to conventional antimicrobial therapy. These efforts are expected to be continuously supported by newly generated basic and translational research data to gain a better understanding of disease pathology while devising new molecularly defined platforms and therapeutic options to improve the treatment of patients with pulmonary infections, particularly in relation to multidrug-resistant pathogens.

Quantitative assessment of betamethasone dual-acting formulation in urine of patients with rheumatoid arthritis and ankylosing spondylitis after single-dose intramuscular administration and its application to long-term pharmacokinetic study

Quantitative evaluation and assessment of pharmacokinetic parameters of Diprospan^® (suspension for injection 7mg/mL (2mg+5mg/mL) of betamethasone) were performed in urine samples taken from patients with rheumatoid arthritis or ankylosing spondylitis for 28days after systemic intramuscular administration in routine clinical practice in an open-comparative prospective cohort study. The maximum betamethasone concentration was reached at day 4 of the follow-up; in some cases, β-phase of elimination of the drug was appeared at day 14 or at day 21 of the follow-up. The deferred β-phase elimination was likely a consequence of the physiological characteristics of the patients or of the influence of non-steroidal agents. The half-life of betamethasone was 8.5days. The elimination rate constant was 2.49h-1; the mean clearance was 4.72L/d. The recommended frequency of the drug administration to its complete elimination was estimated up to 48days. Mann-Whitney test showed no significant differences in pharmacokinetic characteristics between male and female subjects. The prolonged elimination phase was observed in patients with deviations in their body mass index, continual treatment by diclofenac and nimesulide or, possibly, after consuming an alcohol. The study was recorded in Clinical Trials open source with identifier NCT03119454.

Differential contribution of COX-1 and COX-2 derived prostanoids to cortical spreading depression-Evoked cerebral oligemia

Cortical spreading depression (CSD) is considered a significant phenomenon for human neurological conditions and one of its key signatures is the development of persistent cortical oligemia. The factors underlying this reduction in cerebral blood flow (CBF) remain incompletely understood but may involve locally elaborated vasoconstricting eicosanoids. We employed laser Doppler flowmetry in urethane-anesthetized rats, together with a local pharmacological blockade approach, to test the relative contribution of cyclooxygenase (COX)-derived prostanoids to the oligemic response following CSD. Administration of the non-selective COX inhibitor naproxen completely inhibited the oligemic response. Selective inhibition of COX-1 with SC-560 preferentially reduced the early reduction in CBF while selective COX-2 inhibition with NS-398 affected only the later response. Blocking the action of thromboxane A2 (TXA2), using the selective thromboxane synthase inhibitor ozagrel, reduced only the initial CBF decrease, while inhibition of prostaglandin F2alpha action, using the selective FP receptor antagonist AL-8810, blocked the later phase of the oligemia. Our results suggest that the long-lasting oligemia following CSD consists of at least two distinct temporal phases, mediated by preferential actions of COX-1- and COX-2-derived prostanoids: an initial phase mediated by COX-1 that involves TXA2 followed by a later phase, mediated by COX-2 and PGF2alpha.

Diclofenac induces proteasome and mitochondrial dysfunction in murine cardiomyocytes and hearts

BACKGROUND

One of the most common nonsteroidal anti-inflammatory drugs (NSAIDs) used worldwide, diclofenac (DIC), has been linked to increased risk of cardiovascular disease (CVD). The molecular mechanism(s) by which DIC causes CVD is unknown.

METHODS

Proteasome activities were studied in hearts, livers, and kidneys from male Swiss Webster mice treated with either 100mg/kg DIC for 18h (acute treatment) or 10mg/kg DIC for 28days (chronic treatment). Cultured H9c2 cells and neonatal cardiomyocytes were also treated with different concentrations of DIC and proteasome function, cell death and ROS generation studied. Isolated mouse heart mitochondria were utilized to determine the effect of DIC on various electron transport chain complex activities.

RESULTS

DIC significantly inhibited the chymotrypsin-like proteasome activity in rat cardiac H9c2 cells, murine neonatal cardiomyocytes, and mouse hearts, but did not affect proteasome subunit expression levels. Proteasome activity was also affected in liver and kidney tissues from DIC treated animals. The levels of polyubiquitinated proteins increased in hearts from DIC treated mice. Importantly, the levels of oxidized proteins increased while the β5i immunoproteasome activity decreased in hearts from DIC treated mice. DIC increased ROS production and cell death in H9c2 cells and neonatal cardiomyocytes while the cardioprotective NSAID, aspirin, had no effect on ROS levels or cell viability. DIC inhibited mitochondrial Complex III, a major source of ROS, and impaired mitochondrial membrane potential suggesting that mitochondria are the major sites of ROS generation.

CONCLUSION

These results suggest that DIC induces cardiotoxicity by a ROS dependent mechanism involving mitochondrial and proteasome dysfunction.

Impact of 3-Amino-1,2,4-Triazole (3-AT)-Derived Increase in Hydrogen Peroxide Levels on Inflammation and Metabolism in Human Differentiated Adipocytes

Obesity is characterized by an excessive accumulation of fat in adipose tissue, which is associated with oxidative stress and chronic inflammation. Excessive H2O2 levels are degraded by catalase (CAT), the activity of which is decreased in obesity. We investigated the effects of inhibition of catalase activity on metabolism and inflammation by incubating human differentiated adipocytes with 10 mM 3-amino-1,2,4-triazole (3-AT) for 24 h. As expected, the treatment decreased CAT activity and increased intracellular H2O2 levels significantly. Glutathione peroxidase (GPX) activity was also reduced, and the gene expression levels of the antioxidant enzymes GPX4 and peroxiredoxins (1, 3 and 5) were inhibited. Interestingly, this occurred along with lower mRNA levels of the transcription factors nuclear factor (erythroid 2-like 2) and forkhead box O, which are involved in redox homeostasis. However, superoxide dismutase activity and expression were increased. Moreover, 3-AT led to nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation and increased tumor necrosis alpha and interleukin 6 protein and gene expression levels, while lowering peroxisome proliferator-activated receptor gamma (PPARγ) mRNA and protein levels. These alterations were accompanied by an altered glucose and lipid metabolism. Indeed, adipocytes treated with 3-AT showed reduced basal glucose uptake, reduced glucose transporter type 4 gene and protein expression, reduced lipolysis, reduced AMP-activated protein kinase activation and reduced gene expression of lipases. Our results indicate that increased H2O2 levels caused by 3-AT treatment impair the antioxidant defense system, lower PPARγ expression and initiate inflammation, thus affecting glucose and lipid metabolism in human differentiated adipocytes.

Imbalanced insulin action in chronic over nutrition: Clinical harm, molecular mechanisms, and a way forward

The growing worldwide prevalence of overnutrition and underexertion threatens the gains that we have made against atherosclerotic cardiovascular disease and other maladies. Chronic overnutrition causes the atherometabolic syndrome, which is a cluster of seemingly unrelated health problems characterized by increased abdominal girth and body-mass index, high fasting and postprandial concentrations of cholesterol- and triglyceride-rich apoB-lipoproteins (C-TRLs), low plasma HDL levels, impaired regulation of plasma glucose concentrations, hypertension, and a significant risk of developing overt type 2 diabetes mellitus (T2DM). In addition, individuals with this syndrome exhibit fatty liver, hypercoagulability, sympathetic overactivity, a gradually rising set-point for body adiposity, a substantially increased risk of atherosclerotic cardiovascular morbidity and mortality, and--crucially--hyperinsulinemia. Many lines of evidence indicate that each component of the atherometabolic syndrome arises, or is worsened by, pathway-selective insulin resistance and responsiveness (SEIRR). Individuals with SEIRR require compensatory hyperinsulinemia to control plasma glucose levels. The result is overdrive of those pathways that remain insulin-responsive, particularly ERK activation and hepatic de-novo lipogenesis (DNL), while carbohydrate regulation deteriorates. The effects are easily summarized: if hyperinsulinemia does something bad in a tissue or organ, that effect remains responsive in the atherometabolic syndrome and T2DM; and if hyperinsulinemia might do something good, that effect becomes resistant. It is a deadly imbalance in insulin action. From the standpoint of human health, it is the worst possible combination of effects. In this review, we discuss the origins of the atherometabolic syndrome in our historically unprecedented environment that only recently has become full of poorly satiating calories and incessant enticements to sit. Data are examined that indicate the magnitude of daily caloric imbalance that causes obesity. We also cover key aspects of healthy, balanced insulin action in liver, endothelium, brain, and elsewhere. Recent insights into the molecular basis and pathophysiologic harm from SEIRR in these organs are discussed. Importantly, a newly discovered oxide transport chain functions as the master regulator of the balance amongst different limbs of the insulin signaling cascade. This oxide transport chain--abbreviated 'NSAPP' after its five major proteins--fails to function properly during chronic overnutrition, resulting in this harmful pattern of SEIRR. We also review the origins of widespread, chronic overnutrition. Despite its apparent complexity, one factor stands out. A sophisticated junk food industry, aided by subsidies from willing governments, has devoted years of careful effort to promote overeating through the creation of a new class of food and drink that is low- or no-cost to the consumer, convenient, savory, calorically dense, yet weakly satiating. It is past time for the rest of us to overcome these foes of good health and solve this man-made epidemic.

NSAIDs and Cardiovascular Diseases: Role of Reactive Oxygen Species

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most commonly used drugs worldwide. NSAIDs are used for a variety of conditions including pain, rheumatoid arthritis, and musculoskeletal disorders. The beneficial effects of NSAIDs in reducing or relieving pain are well established, and other benefits such as reducing inflammation and anticancer effects are also documented. The undesirable side effects of NSAIDs include ulcers, internal bleeding, kidney failure, and increased risk of heart attack and stroke. Some of these side effects may be due to the oxidative stress induced by NSAIDs in different tissues. NSAIDs have been shown to induce reactive oxygen species (ROS) in different cell types including cardiac and cardiovascular related cells. Increases in ROS result in increased levels of oxidized proteins which alters key intracellular signaling pathways. One of these key pathways is apoptosis which causes cell death when significantly activated. This review discusses the relationship between NSAIDs and cardiovascular diseases (CVD) and the role of NSAID-induced ROS in CVD.

Effects of new-type NSAIDs in preventing post-ERCP pancreatitis

AIM: To compare the effects of new-type versus traditional non-steroid antiinflammtory drugs (NSAIDs) in the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).

METHODS: One hundred and ninety-seven patients who underwent ERCP for choledocholithiasis between May 2012 and May 2013 were randomly divided into three groups: a lornoxicam group, a parecoxib group and a control group. Different drugs were applied for each group. Mean visual analogue score (VAS) and serum levels of amylase and C-reactive protein (CRP) were measured before ERCP and 4, 24 and 48 h after ERCP. Incidences of hyperamylasemia and PEP were observed.

RESULTS: The incidences of PEP in the lornoxicam group, parecoxib group and control group were 4.55%, 9.09% and 10.8%, respectively, and the difference was statistically significant between the parecoxib group and control group (P < 0.05), but not between the lornoxicam group and control group (P > 0.05). The incidences of post-ERCP hyperamylasemia in the parecoxib group and lornoxicam group were significantly lower than that in the control group (9.09%, 15.2% vs 21.5%, both P < 0.01). Serum CRP level at 4 h after ERCP was significantly lower in both treatment groups than in the control group (both P < 0.01). Mean VAS at 4 h after ERCP was significantly lower in both treatment groups than in the control group (both P < 0.01).

CONCLUSION: NSAIDs like lornoxicam and parecoxib can prevent the occurrence of hyperamylasemia induced by ERCP. Parecoxib could prevent the occurrence of PEP. Both drugs can alleviate pain and inflammatory reactions after the endoscopic procedure. As a new type of NSAIDs, selective cyclooxygenase-2 (COX-2) inhibitors might be more useful in preventing PEP.