Acid Oxidation Research Articles

Maximum Aerobic Function: Clinical Relevance, Physiological Underpinnings, and Practical Application.

The earliest humans relied on large quantities of metabolic energy from the oxidation of fatty acids to develop larger brains and bodies, prevent and reduce disease risk, extend longevity, in addition to other benefits. This was enabled through the consumption of a high fat and low-carbohydrate diet (LCD). Increased fat oxidation also supported daily bouts of prolonged, low-intensity, aerobic-based physical activity. Over the past 40-plus years, a clinical program has been developed to help people manage their lifestyles to promote increased fat oxidation as a means to improve various aspects of health and fitness that include reducing excess body fat, preventing disease, and optimizing human performance. This program is referred to as maximum aerobic function, and includes the practical application of a personalized exercise heart rate (HR) formula of low-to-moderate intensity associated with maximal fat oxidation (MFO), and without the need for laboratory evaluations. The relationship between exercise training at this HR and associated laboratory measures of MFO, health outcomes and athletic performance must be verified scientifically.

PRELIMINARY RESULTS ON THE USING TANDEM MASS SPECTROMETRY IN DIAGNOSIS OF INHERITED METABOLIC DISEASES

BACKGROUND According to the results of the researches common indexes of the prevalence of inherited metabolic diseases (IMD) varies from 1 to 800 on 1 to 2500 alive newborns. IMD are taking one of the first places among children pathology, early children death (40%) and disability[1]. According to systematic review of the 43 forms of the inborn errors of metabolism are related to unexpected death of newborns. For IMD it is common to have a wide spectrum of the unusual clinical manifestation, often they are not diagnosed, while well timed diagnoses and proper treatment are able to prevent severe systematic lesions, which lead to death and disability[2]. For that reason one of the most significant problems of the modern pediatrics is to early diagnosis of IMD. The only way to diagnosis of orphan metabolic diseases is the tandem mass spectrometry (TMS) [3]. AIM Scientifically substantiate the need for implementation of selective screening IMD of children using TMS method in Republic of Kazakhstan (RK) for early diagnosis, therapy of the inherited metabolic diseases, to reduce disability and death rate. MATERIALS AND METHODS Material of the research – dry blood spots, taken using standard methodology on filtered DBS papers, which are used in RK in the program of neonatal screening (for retrospective research – archived samples of the dry blood spots of the children dead during first year of life). Method of the research is tandem mass spectometry (QSight Perkin Elmer). RESULTS Analysis of the archived dry blood spot samples showed metabolic deviations in 20.4% of the cases. The detected changes are related to amino acids metabolic disorders, defects of -oxidation of the fat acids, decrease activity of the glucocerebrosidase (Gaucher’s disease) and sphingomyelinase (Nimman – Pick disease). Results of the selective screening have shown metabolic disorders in 5% of the cases (defects of -oxidation of the fat acids, aminoacidopathy, organic aciduria). CONCLUSIONS The preliminary results of the using TMS for the diagnosis of IMD have shown the need for implementation of selective screening IMD using TMS, which is able to conduct diagnosis of 75 metabolites of 49 IMD in single blood spot, which were not detected in RK previously. Taking into the consideration economic expenses of the government, related to the costs of the systematic treatment, medical service, life expectancy and lifelong support of the disabled children with IMD, early detection of orphan metabolic diseases is the vital condition of the decrease of newborn and children death rate, sickness rate and disability. This research study was carried out as a part of a scientific project funded by West Kazakhstan Marat Ospanov Medical University.

Overcoming the Deactivation of Pt/CNT by Introducing CeO2 for Selective Base-Free Glycerol-to-Glyceric Acid Oxidation

Catalytic base-free oxidation of biomass-derived glycerol represents a promising approach for the value-added utilization of glycerol. However, the commonly used Pt/carbon nanotubes (Pt/CNT) cataly...

Photoinduced damage of AsLOV2 domain is accompanied by increased singlet oxygen production due to flavin dissociation

Flavin mononucleotide (FMN) belongs to the group of very efficient endogenous photosensitizers producing singlet oxygen, 1O2, but with limited ability to be targeted. On the other hand, in genetically-encoded photosensitizers, which can be targeted by means of various tags, the efficiency of FMN to produce 1O2 is significantly diminished due to its interactions with surrounding amino acid residues. Recently, an increase of 1O2 production yield by FMN buried in a protein matrix was achieved by a decrease of quenching of the cofactor excited states by weakening of the protein-FMN interactions while still forming a complex. Here, we suggest an alternative approach which relies on the blue light irradiation-induced dissociation of FMN to solvent. This dissociation unlocks the full capacity of FMN as 1O2 producer. Our suggestion is based on the study of an irradiation effect on two variants of the LOV2 domain from Avena sativa; wild type, AsLOV2 wt, and the variant with a replaced cysteine residue, AsLOV2 C450A. We detected irradiation-induced conformational changes as well as oxidation of several amino acids in both AsLOV2 variants. Detailed analysis of these observations indicates that irradiation-induced increase in 1O2 production is caused by a release of FMN from the protein. Moreover, an increased FMN dissociation from AsLOV2 wt in comparison with AsLOV2 C450A points to a role of C450 oxidation in repelling the cofactor from the protein.

Effect of different surface functional groups on carbon supports toward methanol electro-oxidation of Pt nanoparticles

With an increased demand for efficient energy conversion system, nanoscale electrocatalysts have been intensively studied for high activity and stability. However, carbon support for nanoparticulate electrocatalyst has been generally thought to be inert for reaction pathway on metal nanocrystals. Therefore, material design for carbon support has mainly focused on development of high surface area with engineered pore structure, while surface state of the support has been largely neglected. Here, we demonstrate that surface functionalization of carbon support can modulate catalytic performance of Pt nanoparticle toward methanol electro-oxidation. Vulcan carbon (VC) surface was successfully modified by either acid oxidation or urea annealing, resulting in oxygen-rich (O-VC) and nitrogen-rich (N-VC) surface states, respectively. Modified surface state of carbon supports were investigated with XPS spectra. With controlled experiments, uniform Pt nanoparticles (d ~ 5 nm) were deposited on each carbon support for the same electrochemical surface area. Through high-resolution XPS analysis, electronic transfer from nitrogen to Pt was monitored in Pt/N-VC. With electron-enriched surface, Pt/N-VC reveals less oxophilic surface property compared to Pt/VC and Pt/O-VC. Notably, methanol electro-oxidation reaction largely depended on types of functional groups. Compared to Pt/VC, methanol oxidation decreased 30% in oxygen-rich Pt/O-VC after surface oxidation, while reaction rate increased double in nitrogen-rich Pt/N-VC. From CO bulk oxidation result, improved MOR activity of Pt/N-VC is attributed to larger number of available Pt active sites from attenuated adsorption of oxygen species. Therefore, this study highlights the importance of surface engineering in carbon supports for electrocatalysis.

Kinetics of the Oxidation of Protocatechuic and Gallic Acids by Atmospheric Oxygen in the Presence of Laccase from T. versicolor

The oxidation of 3,4-dihydroxybenzoic and 3,4,5-trihydroxybenzoic acids by atmospheric oxygen in the presence of laccase from T. versicolor is studied via electronic absorption spectroscopy. The molar extinction coefficients of intermediate and final products, the rate constants, and the initial rates of oxidation are determined by means of the maximum likelihood approach. The parameters of the Michaelis–Menten equation are calculated. Polymeric oxidation products are isolated, and their composition is investigated via mass spectrometry and 13C NMR spectroscopy.

Effect of Natural Cytokine Complex on Metabolism of Smooth Muscle Cells in Myocardial Arteries under Normal Conditions and during Hemodynamic Overload.

Histoenzymological methods were employed to examine the effects of systemically administered natural cytokine complex including IL-1, IL-2, IL-6, TNFα, MIF, and TGFβ on metabolism of smooth muscle cells in intramural myocardial arteries under physiological conditions and during acute hemodynamic overload of the heart. Natural cytokine complex markedly inhibited metabolism of vascular smooth muscle cells under control conditions and during acute experimental aortal stenosis. In vascular smooth muscle cells, deceleration of tricarboxylic acid cycle, redistribution of the fluxes in glycolytic cascade and its inhibition, down-regulation of oxidation of free fatty acids and their metabolites, and inhibition of the shuttle systems and biosynthetic processes were observed. Inhibition of metabolism in the vascular wall of myocardial arteries correlated with a decrease in their tone and could be partially determined by a decrease in contractile activity of smooth muscle cells. These findings do not exclude the involvement of other factors and mechanisms in down-regulation of metabolism in vascular myocytes in response to increased cytokines levels of in the blood, including their direct effect on biochemical processes in cells.

Combined Effects of Diatom-Derived Oxylipins on the Sea Urchin Paracentrotus lividus.

Oxylipins are diatom-derived secondary metabolites, deriving from the oxidation of polyunsatured fatty acids that are released from cell membranes after cell damage or senescence of these single-celled algae. Previous results revealed harmful toxic effects of polyunsaturated aldehydes (PUAs) and hydroxyacids (HEPEs) on sea urchin Paracentrotus lividus embryonic development by testing individual compounds and mixtures of the same chemical group. Here, we investigated the combined effects of these compounds on sea urchin development at the morphological and molecular level for the first time. Our results demonstrated that oxylipin mixtures had stronger effects on sea urchin embryos compared with individual compounds, confirming that PUAs induce malformations and HEPEs cause developmental delay. This harmful effect was also confirmed by molecular analysis. Twelve new genes, involved in stress response and embryonic developmental processes, were isolated from the sea urchin P. lividus; these genes were found to be functionally interconnected with 11 genes already identified as a stress response of P. lividus embryos to single oxylipins. The expression levels of most of the analyzed genes targeted by oxylipin mixtures were involved in stress, skeletogenesis, development/differentiation, and detoxification processes. This work has important ecological implications, considering that PUAs and HEPEs represent the most abundant oxylipins in bloom-forming diatoms, opening new perspectives in understanding the molecular pathways activated by sea urchins exposed to diatom oxylipins.

Mechanistic insights into the in vitro metal-promoted oxidation of (di)azine hydroxamic acids: evidence of HNO release and N,O-di(di)azinoyl hydroxylamine intermediate

HNO is released through a one-electron oxidation of the hydroxamic acid along with the N,O-di(di)azinoylhydroxylamine intermediate.

Abstract C078: Substituted oxindoles as AMP-activated protein kinase (AMPK) inhibitors and their evaluation in models of leukemia

Abstract AMP-Activated protein kinase (AMPK) acts as a central metabolic sensor at the interface of metabolic and signaling networks. Activated AMPK promotes multiple catabolic processes to generate ATP, such as glucose uptake, glycolysis, fatty acid uptake and oxidation, and mitochondrial biogenesis. In addition, AMPK activation suppresses the cell cycle, and anabolic processes such as the mammalian Target of Rapamycin Complex 1 (mTORC1)-dependent protein synthesis and fatty acid biosynthesis via inactivating phosphorylation of cytosolic acetyl-CoA carboxylase 1 (ACC1) and mitochondrial ACC2. The activation of AMPK under conditions of energetic stress is modulated by an allosteric mechanism where the depletion of ATP promotes AMP binding at the γ subunit of AMPK with a subsequent conformational change in the catalytic α subunit. In the context of cancer AMPK has been reported to promote tumor survival and progression under hypoxia and the maintenance of cancer stem cells (CSCs). A major challenge to interrogating the therapeutic potential of targeting AMPK in cancer is the lack of potent and selective small molecule inhibitors. Compound C has been widely used as an AMPK inhibitor, but it lacks potency and has a poor selectivity profile. The multi-kinase inhibitor, sunitinib, has demonstrated potent nanomolar inhibition of AMPK activity, but has broad-spectrum activity across the kinome. Although sunitinib targets multiple kinases, its nanomolar potency for AMPK inhibition and large scope for chemical substitution on the core oxindole ring make it an attractive lead for AMPK inhibitor development. We have used a computational model of sunitinib docked into the ATP-binding site of the α subunit of AMPK to design and synthesize several series of oxindoles to examine structural modifications to improve AMPK inhibition and selectivity. These candidate inhibitors were evaluated against the activity of the α1 and α2 isoforms of AMPK using the TR-FRET assay and cell engagement was determined by ELISA, measuring p-ACC(Ser79), in the chronic myeloid leukemia K562 cell line. Our assays identified two novel, potent oxindole-based AMPK inhibitors that hadsignificantly reduced binding affinity when compared with sunitinib against members of the receptor tyrosine kinase (RTK) family, including VEGFR1, VEGFR2 and CSF1R, as well as BTK, a member of the B cell receptor (BCR) signaling pathway. Interestingly, cellular AMPK inhibition did not impact cell viability or result in cytotoxicity in K562 cells and may only sensitize these cells to chemotherapy. AMPK inhibition may be a more effective strategy to eliminate cancer cells in hypoxic microenvironments or against certain cell types, such as CSCs, that may be more reliant on AMPK for survival. Our current studies are designed to examine our AMPK inhibitors as single agents and in combination therapy in cancer cells grown under hypoxia and in CSC populations in order to eliminate these drug-resistant cancer cell populations with an aim to prevent cancer recurrence. In summary, we have developed two novel, potent AMPK inhibitors that were designed to interact with the DFG motif in the ATP-binding site of the α subunit of AMPK that are undergoing evaluation in advanced models of leukemia. Citation Format: Christopher J Matheson, Kimberly A Casalvieri, Donald S Backos, Craig T Jordan, Philip Reigan. Substituted oxindoles as AMP-activated protein kinase (AMPK) inhibitors and their evaluation in models of leukemia [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C078. doi:10.1158/1535-7163.TARG-19-C078

Changes in fatty acids composition, antioxidant potential and induction period of UHT-treated tea whitener, milk and dairy drink

BackgroundIn developing and developed countries, several versions of safe and shelf-stable Ultra High Temperature, UHT-treated products are manufactured. Terminologies and formulations of UHT-treated tea whitener, milk and dairy drink considerably vary. Comprehensive studies have been performed on UHT-treated milk; however, fatty acids compositional changes and oxidation status of UHT-treated tea whitener and dairy drink at different storage intervals have not been reported in literature.MethodsUHT-treated tea whitener, milk and dairy drink samples (450 each) of the same manufacturing date were purchased from the market and stored at ambient temperature (25-30 °C) for 90 days. At the time of collection, all the samples were only one week old. Samples of UHT-treated tea whitener, milk and dairy drink were regarded as treatments and every treatment was replicated five times. Chemical composition, fatty acid profile, 2, 2-Diphenyl-1-picrylhydrazyle (DPPH) radical scavenging activity, total antioxidant activity, reducing power, antioxidant activity in linoleic acid system and induction period were determined at 0, 45 and 90 days of storage.ResultsFat content in freshly collected samples of UHT treated-tea whitener, milk and dairy drink were 6 and 3.5%. UHT treated milk had highest total antioxidant capacity, antioxidant activity in linoleic acid and 2, 2-Diphenyl-1-picrylhydrazyle (DPPH) free radical scavenging activity followed by UHT tea whitener and dairy drink. In freshly collected samples of UHT-treated milk, concentrations vitamin A and E were 0.46 μg/100 g and 0.63 mg/100 g, respectively. UHT-treated tea whitener had the lowest concentrations of vitamin A and E. With the progression of storage period, amount of vitamin A and E decreased. In freshly collected samples, amount of short, medium and unsaturated fatty acids in UHT-treated milk were 10.54, 59.71 and 27.44%, respectively. After 45 days of storage of UHT-treated milk, the loss of short, medium and unsaturated fatty acid was 7%, 7.1 and 5.8%, respectively. After 90 days of storage of UHT-treated milk, the loss of short, medium and unsaturated fatty acid was 8.53, 13.51 and 11.88%, accordingly. After 45 days of storage of UHT-treated tea whitener, the loss of medium and unsaturated fatty acid was 1.6 and 0.99%, respectively. After 90 days of storage, the loss of medium and unsaturated fatty acids were 8.2 and 6.6%, respectively. The induction period of fresh UHT-treated tea whitener, milk and dairy drink was 15.67, .74 and 7.27 h. Strong correlations were recorded between induction period and peroxide value of UHT-treated products.ConclusionThis investigation disclosed that UHT-treated tea whitener had 6% fat content with no short-chain fatty acids. Antioxidant capacity of UHT-treated milk was higher than dairy drink and tea whitener. Due to the presence of partially hydrogenated fat, oxidative stability of UHT-treated tea whitener was better than UHT-treated milk and dairy drink. Vitamin A and E was not found in UHT-treated tea whitener. For the anticipation of oxidative stability of UHT-treated milk, dairy drink and tea whitener, induction period/ Rancimat method can be used.

3070Caloric restriction increases lifespan in dilated cardiomyopathy mice by enhancing mitochondrial quality control

Abstract Background/Introduction Dilated cardiomyopathy (DCM) is a leading cause of heart failure (HF) in young and middle aged individuals worldwide. Alterations in mitochondrial dynamics (fusion/fission) and quality control (mitophagy) are critical for normal cardiac function. Imbalanced mitochondrial dynamics towards fission has been shown to contribute to DCM development in mice with ablation of the mitochondrial protease YME1L, which results in altered OPA1 processing precluding mitochondrial fusion. In these mice, the DCM phenotype includes a metabolic reprogramming of cardiomyocytes, shifting from fatty acid (FA) oxidation towards glucose. High fat diet (HFD) in these mice results in reversal of this metabolic reprogramming and rescue from DCM despite the genetic defect (lack of YME1) still present. These results opened a new venue for dietary approaches as a therapeutic strategy in HF. To understand whether the fat itself contained in the HFD was responsible of HF rescue, we studied the trajectories of cardiac function in mice with altered mitochondrial dynamics under HFD, caloric restriction and control chow. Methods Cardiomyocyte-specific Yme1l knock-out (cYKO) male mice (N=10–15) known to develop DCM phenotype at 20–25 weeks of age were randomized to 3 different diets (1: HFD containing >30% crude fat; 2: non-fat diet containing <0.5% crude fat, and 3: control diet containing 10% crude fat) at 10 weeks of age. Every 10 weeks, cardiac function was tested by echocardiography. At 30 weeks, animals underwent a multitracer microPET/CT (glucose and FA uptake) to evaluate myocardial substrate utilization. At the end of the study, animals were sacrificed and hearts were harvested for histological and further tissue analyses. Results As expected, HFD was associated with a better left ventricular ejection fraction (LVEF; %) at 30 weeks: 37.97±8.59 vs. 29.16±8.9 in control diet, p=0.04. This functional improvement was associated with an increase in FA uptake on microPET/CT. Non-fat diet was associated with even higher LVEF at 30 weeks: 44.94±11 vs. 29.16±8.9 in control diet, p=0.0001, as well as smaller LV diameter (mm): 3.58±0.29 vs. 4.3±0.39 in control diet, p<0.0001 (A). Lifespan of mice on non-fat diet was significantly prolonged (70% extension compared to control) (B). Enhanced mitochondrial clearance (mitophagy) mediated by Parkin, together with an increase in autophagy related protein as LC3B was identified in the non-fat diet group (C). Conclusion Different dietary approaches have been shown to be beneficial in the prevention of DCM in mice with altered mitochondrial dynamics. Caloric restriction (non-fat diet) is able to prevent DCM, reverse metabolic reprogramming, increase mitochondrial quality control and ultimately prolong lifespan in mice with genetic defect associated with altered mitochondrial dynamics. Interventions aiming at enhancing cardiac mitophagy might represent a new therapeutic option in DCM.

Inhibitors of Eicosanoid Biosynthesis Reveal that Multiple Lipid Signaling Pathways Influence Malaria Parasite Survival in Anopheles gambiae.

Eicosanoids are bioactive signaling lipids derived from the oxidation of fatty acids that act as important regulators of immune homeostasis and inflammation. As a result, effective anti-inflammatory drugs have been widely used to reduce pain and inflammation which target key eicosanoid biosynthesis enzymes. Conserved from vertebrates to insects, the use of these eicosanoid pathway inhibitors offer opportunities to evaluate the roles of eicosanoids in less-characterized insect systems. In this study, we examine the potential roles of eicosanoids on malaria parasite survival in the mosquito Anopheles gambiae. Using Plasmodium oocyst numbers to evaluate parasite infection, general or specific inhibitors of eicosanoid biosynthesis pathways were evaluated. Following the administration of dexamethasone and indomethacin, respective inhibitors of phospholipid A2 (PLA2) and cyclooxygenase (COX), oocyst numbers were unaffected. However, inhibition of lipoxygenase (LOX) activity through the use of esculetin significantly increased oocyst survival. In contrast, 12-[[(tricyclo[3.3.1.13,7]dec-1-ylamino)carbonyl]amino]-dodecanoic acid (AUDA), an inhibitor of epoxide hydroxylase (EH), decreased oocyst numbers. These experiments were further validated through RNAi experiments to silence candidate genes homologous to EH in An. gambiae to confirm their contributions to Plasmodium development. Similar to the results of AUDA treatment, the silencing of EH significantly reduced oocyst numbers. These results imply that specific eicosanoids in An. gambiae can have either agonist or antagonistic roles on malaria parasite survival in the mosquito host.

Novel functionalization treatment of MWCNTs for unmanned aerial vehicle structure

Present typescript encompasses the influences of functionalization on the carbon nanotubes (CNTs) using acid oxidation which has been widely reported not only as a purification process but also as functionalization process because it is an effect on the outer surface on CNTs. Therefore, using strong acid effect and high power sonication in addition to the nature of the acid mixture (H2SO4/HNO3) with CNTs confirm that adequate volume of carboxyl groups decorate the outer surface, this functionalization process improve the dispersibility of the CNT in the response of the final dimension of the CNTs. Because of using a high temperature for a long time more than 6 hours.This work interested in the aspect ratio (L/D) and the final shape of the tubes by using a mild temperature process 50°C with concentration acid for not long time 5 hours, in an attempt to make experimental condition which guarantees good functionalization of the surface of MWNTs with minimizing the CNTs damage, The results were confirmed by Thermogravimetry Analysis (TGA), Raman Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) analysis.In addition to the functionalization process we try to save the loss in the weight during the filtration step, in addition to decrease the time during filtration of the materials after sonication. Where the results show that actually functionalization has been done with an adequate amount at this condition, and the dilution for 2 days before filtration have been approved to be easier and faster than direct filtration after treatment.

Insights into enhanced adsorptive removal of Rhodamine B by different chemically modified garlic peels: Comparison, kinetics, isotherms, thermodynamics and mechanism

Garlic peel, a typical agricultural by-product, was modified by three chemical modification methods, including oxidation with H2O2, acid oxidation with HNO3/C6H8O7, and alkaline saponification with NaOH, respectively. Unmodified garlic peel (unmodified-GP) and as-synthesized chemically modified garlic peels (H2O2-GP, HNO3-GP, CA-GP and NaOH-GP) were fully characterized and evaluated as biosorbents for the removal of Rhodamine B (RhB). Results showed that acid oxidation could lead to the increase of surface area and acidic oxygen groups, which were beneficial for the adsorption for toxic dyes. Notably, HNO3-GP turned out to be most efficient among the five studied garlic peels, the adsorption capacity of which was 3.5 times of unmodified-GP when initial RhB concentration was 15 mg L−1. Adsorption kinetics, isotherms and thermodynamics of HNO3-GP were investigated to gain insights into the adsorption behaviors. In addition, the adsorption of RhB was pH dependent, and 95.8 ± 1.1% of the adsorbed RhB could be eluted by 0.1 mol L−1 NaOH. Adsorption-desorption studies showed HNO3-GP was reusable. Moreover, on the basis of experimental data and analysis of FT-IR and XPS of HNO3-GP before and after adsorption, electrostatic interaction and hydrogen bonding played an important role during the adsorption process. This work systematically studied the effect of oxidation, acid oxidation and alkaline saponification as modification methods, and demonstrated acid oxidation with strong acid was an effective method to improve adsorption capacities of agricultural by-products for toxic dyes.

Fatty Acid Content, Oxidation Markers and Mercury in Fish Oil Supplements Commercialized in Brasília, Brazil

Fish oil supplements are good sources of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, which are important in the prevention and treatment of hypertriglyceridemia. The purpose of this study was to examine the content of EPA and DHA, oxidation markers and mercury of fish oil supplements marketed in Brasilia, Brazil. Fatty acid contents were determined by gas chromatography using internal (C23:0) and external methyl ester standards. For this analysis, samples were prepared by alkali-catalyzed methylation with boron trifluoride (14% in methanol). Mercury was determined by direct vapor detection method. Oxidation markers were evaluated by measuring peroxide value (PV), anisidine value (AV) and by calculating TOTOX. The adequacy of EPA and DHA ranged from 75.9 to 105.1% and from 88.9 to 137.4%, respectively, compared to the information in the label. Mercury concentration was above limit of quantification levels, between 11 and 15 mg/kg in 14.4% of the products. Twenty percent of the products exceeded recommended levels of PV and TOTOX. Despite the high percentage of adequacy of the parameters analyzed, about 2/3 of the products showed some inadequacies according to the law. These data deserve concern due to the potential side effects of oxidized and contaminated fish oils to their proclaimed health benefits. This survey shows the relevance of constant monitoring of fish oil quality, considering current legislation and scientific advance. DOI: http://dx.doi.org/10.17807/orbital.v11i3.1390

Noncovalent Hydrogen Isotope Effects in the Catalytic Complexes of Lipoxygenase

Zero-point energies (ZPEs) of intermolecular, noncovalent vibrations and isotope effects, induced by noncovalent interactions, are computed for complexes of lipoxygenase, which induces enzymatic oxidation of arachidonic acids in living organisms. For complexes with hydrogen, water, methane, and ethylene molecules noncovalent isotope effects are in the range 1.2–1.8, i.e. these isotope effects are much less than the experimentally detected effects induced by tunneling.

Electrocatalysis: Mesoporous Decoration of Freestanding Palladium Nanotube Arrays Boosts the Electrocatalysis Capabilities toward Formic Acid and Formate Oxidation (Adv. Energy Mater. 25/2019)

Electrocatalysis: Mesoporous Decoration of Freestanding Palladium Nanotube Arrays Boosts the Electrocatalysis Capabilities toward Formic Acid and Formate Oxidation (Adv. Energy Mater. 25/2019)

1866-P: Peripancreatic Adipose Tissue Protects against Ectopic Fat Accumulation in the Liver

Peripancreatic adipose tissue (PAT) is an understudied visceral fat depot that surrounds pancreas and is in touch with spleen and liver. Recent previous studies suggest that obesity-associated PAT inflammation accelerates pancreatic neoplasia in KrasG12D mice and that PAT conditioned-medium from pre-diabetic rats (9 weeks on high-fat diet; HFD) stimulates insulin secretion, proliferation and apoptosis in INS-1 cells. In this study, we aimed to better characterize PAT functionality in the context of HFD-induced obesity. PAT is a very small depot (0,5 ±0,04 mg) with a relatively high number of small adipocytes in unchallenged mice on chow, and we found that PAT expansion is less pronounced at early stages of HFD-feeding compared to the expansion of inguinal (IWAT), gonadal (GWAT) and mesenteric adipose tissues (MWAT). After 8-weeks HFD feeding the expansion of PAT was however comparable to the other three fat depots, but still PAT was more protected against the deleterious effects of HFD on adipose tissue inflammation and insulin resistance as judged by gene expression analysis (adiponectin, insulin receptor and inflammation markers). Feeding after 16-weeks HFD reduced the glucose and lipid uptake in all fat depots however, it was less pronounced in PAT; both fatty acid and glucose oxidation rates were higher in PAT compared to IWAT, GWAT and MWAT. Moreover, we noted that PAT is the only fat depot where the tissue weight correlates positively with liver weight in HFD-induced obese mice, and surgical removal of PAT followed by 16-week-HFD-feeding was associated with increased hepatic triglyceride content and accumulation of more and larger lipid droplets. PAT did not regenerate during this 16-week HFD time course suggesting that its precursor cells reside within the depot. Taken all data together, we propose that PAT, although it is located in the visceral compartment, can be considered as a metabolically/immunologically healthy fat depot that protects against hepatic steatosis in advanced obesity. Disclosure B. Chanclón: None. P. Micallef: None. E. Banke Nordbeck: None. Y. Wu: None. B. Wilder: None. J. Kanerva: None. P. Rorsman: None. I. Wernstedt Asterholm: None.

Osmium tetroxide catalyzed oxidation of mefenamic and tolfenamic acids with alkaline chloramine-B: Delineation of kinetic, mechanistic and catalytic chemistry

Abstract The kinetic oxidation of mefenamic acid (MEF) and tolfenamic acid (TOL), which therapeutically belongs to the class of non-steroidal anti-inflammatory drugs (NSAIDs) finds extensive applications in pharmaceuticals. The kinetics of oxidation of MEF and TOL by chloramine-B (CAB) in the presence of osmium tetroxide (OsO4) catalyst has been investigated at 313 K in alkaline medium. The oxidation behavior of these two drugs is similar with a first-order dependence of rate on both [CAB]0 and [OsO4] and a negative-fractional-order dependence on [NaOH]. The order with respect to [Drug]0 is zero. The dielectric effect is negative. Activation parameters have been evaluated for the composite reaction as well as with respect to catalyst. The oxidation products were characterized by GC–MS analysis. The observed experimental results have been justified by a plausible reaction mechanism. The relevant kinetic rate laws have been deduced.