Lipid Hydroperoxide Content Research Articles

Cardiotoxic and Cardioprotective Effects of Methylene Blue in the Animal Model of Cardiac Ischemia and Reperfusion.

Background/Objectives: Treatment of patients with myocardial ischemic diseases crucially involves cardiac reperfusion (CR). However, oxidative stress and tissue lesions caused by CR may also lead to lethal complications, such as arrythmias and vasoplegic syndrome (VS). Although methylene blue (MB) has long been used to treat VS due to cardiac ischemia and reperfusion (CIR) and/or surgery because of its vascular effects, MB's effects on the heart are unclear. Therefore, we investigated the potential cardioprotective or arrhythmogenic effects of MB in an animal model of CIR. To this end, 12-16-week-old male Wistar rats were divided into four experimental groups: (a) rats subjected to SHAM surgery with no ischemia; (b) rats subjected to CIR and treated with a vehicle (SS + CIR); and (c) rats subjected to CIR and treated with 2 mg/kg i.v. MB before ischemia (MB + ISQ) or (d) after ischemia but before reperfusion (ISQ + MB). An ECG analysis was used to evaluate the incidence of ventricular arrhythmias (VAs), atrioventricular blocks (AVBs), and lethality (LET) resulting from CIR. After CIR, rat hearts were removed for histopathological analysis and lipid hydroperoxide (LH) measurements. Results: The incidence of VA, AVB, and LET was significantly increased in the MB + ISQ group (VA = 100%; AVB = 100%; LET = 100%) but significantly reduced in the ISQ + MB group (VA = 42.8%; AVB = 28.5%; LET = 21.4%) compared with the SS + CIR group (VA = 85.7%; AVB = 71.4%; LET = 64.2%). LH concentration was significantly reduced in both MB-treated groups, but myocardial injuries were increased only in the MB + ISQ group when compared with the SS + CIR group. Conclusions: These results indicate that MB produces a biphasic effect on CIR, with cardiotoxic effects when administered before cardiac ischemia and cardioprotective effects when administered after ischemia but before cardiac reperfusion.

Effects of concurrent training and N-acetylcysteine supplementation on cardiac remodeling and oxidative stress in middle-aged spontaneously hypertensive rats

BackgroundThis study evaluated the effects of concurrent isolated training (T) or training combined with the antioxidant N-acetylcysteine (NAC) on cardiac remodeling and oxidative stress in spontaneously hypertensive rats (SHR).MethodsSix-month-old male SHR were divided into sedentary (S, n = 12), concurrent training (T, n = 13), sedentary supplemented with NAC (SNAC, n = 13), and concurrent training with NAC supplementation (TNAC, n = 14) groups. T and TNAC rats were trained three times a week on a treadmill and ladder; NAC supplemented groups received 120 mg/kg/day NAC in rat chow for eight weeks. Myocardial antioxidant enzyme activity and lipid hydroperoxide concentration were assessed by spectrophotometry. Gene expression of NADPH oxidase subunits Nox2, Nox4, p22 phox, and p47 phox was evaluated by real time RT-PCR. Statistical analysis was performed using ANOVA and Bonferroni or Kruskal–Wallis and Dunn.ResultsEchocardiogram showed concentric remodeling in TNAC, characterized by increased relative wall thickness (S 0.40 ± 0.04; T 0.39 ± 0.03; SNAC 0.40 ± 0.04; TNAC 0.43 ± 0.04 *; * p < 0.05 vs T and SNAC) and diastolic posterior wall thickness (S 1.50 ± 0.12; T 1.52 ± 0.10; SNAC 1.56 ± 0.12; TNAC 1.62 ± 0.14 * mm; * p < 0.05 vs T), with improved contractile function (posterior wall shortening velocity: S 39.4 ± 5.01; T 36.4 ± 2.96; SNAC 39.7 ± 3.44; TNAC 41.6 ± 3.57 * mm/s; * p < 0.05 vs T). Myocardial lipid hydroperoxide concentration was lower in NAC treated groups (S 210 ± 48; T 182 ± 43; SNAC 159 ± 33 *; TNAC 110 ± 23 *# nmol/g tissue; * p < 0.05 vs S, #p < 0.05 vs T and SNAC). Nox 2 and p22 phox expression was higher and p47 phox lower in T than S [S 1.37 (0.66–1.66); T 0.78 (0.61–1.04) *; SNAC 1.07 (1.01–1.38); TNAC 1.06 (1.01–1.15) arbitrary units; * p < 0.05 vs S]. NADPH oxidase subunits did not differ between TNAC, SNAC, and S groups.ConclusionN-acetylcysteine supplementation alone reduces oxidative stress in untreated spontaneously hypertensive rats. The combination of N-acetylcysteine and concurrent exercise further decreases oxidative stress. However, the lower oxidative stress does not translate into improved cardiac remodeling and function in untreated spontaneously hypertensive rats.

Blue light as an important factor increasing plant tolerance to acute photooxidative stress

Previous studies have confirmed the stimulating effect of blue light on phenolic compound accumulation and emphasized that sufficient dose of blue light is essential for biosynthesis of B-dihydroxylated flavonoids with enhanced antioxidant properties (under UV-lacking conditions). This study investigates the importance of blue light and complex role of phenolic compounds in plant tolerance against acute photooxidative stress. Hordeum vulgare (L. Cv. Bojos) seedlings were acclimated to different light spectra (blue, green:red 1:1, and white composed of blue:green:red 1:1:1) at total irradiance 400 µmol.m−2.s−1. Subsequently, they were subjected to a 3-hour combined stress induced by high photosynthetically active (850–950 µmol.m−2.s−1) and UV-B (2.0–2.5 W.m−2) radiation. Content of flavonoids, expression of genes involved in their biosynthesis (phenylalanine ammonia-lyase, chalcone synthase, flavonoid 3′-hydroxylase), and antioxidant activity of plant extracts were significantly highest in plants acclimated to blue light. As an indicator of reactive oxygen species interaction with biomolecules, the content of lipid hydroperoxides was estimated. It was demonstrated that plants acclimated to blue light revealed significantly lower extent of lipid peroxidation compared to those acclimated to white or green:red light. Plants exposed to combined light-induced stress for 3 hours exhibited pronounced disruption of PSII function: FV/FM tended to decrease proportionally with decreasing amount of blue photons in the treatments. Additionally, stress exposure upregulated the expression of genes related to phenolic compounds but not genes encoding antioxidant enzymes. We confirmed higher resistance of plants acclimated to blue light and presume that phenolic compounds are significantly involved in protection during the acute phase of stress.

Structural characteristics and emulsifying properties of linear dextrin/eicosapentaenoic acid composites: Effect of the degree of polymerization

This work aimed at building functional emulsions based on the linear dextrins (LDs) emulsion system. The gradient polyethylene glycol (PEG) precipitaion method was used to fractionate LDs into fractions with different degrees of polymerization (DP). A package, and co-precipitation procedure of LDs, and eicosapentaenoic acid (EPA) was used to fabricate LDs-EPA composites. The gas chromatograph, Fourier transform infrared spectroscopy, X-ray diffraction and differential scanning calorimetry analyses affirmed the formation of the LDs-EPA composites. The sizes of these composites were 38.55 nm, 59.14 nm to 80.62 nm, respectively, and they had good amphiphilicity. Compared with LDs, these LDs-EPA composites stabilized Pickering emulsion had higher stability and antioxidant capacity. Their emulsifying ability was positively correlated with the DP values of LDs. Furthermore, the oxidation stability results showed that LDsF10-EPA emulsion had the lowest lipid hydroperoxide (LHs) content, malondioxide (MDA) content and hexal concentration, which were 138.75 mmol kg−1 oil, 15.50 mmol kg−1 oil and 3.83 μmol kg−1 oil, respectively. The study provided a new idea and application values for the application of LDs in emulsion.

Characterization of modified starch-based complexes-stabilized linolenic acid emulsions and their enhanced oxidative stability in vitro gastrointestinal digestion

A new approach of fabricating α-linolenic acid emulsions with enhanced oxidative stability in vitro digestion was established, using covalent octenyl succinic anhydride starch (OSAS)-soy protein (SP)-epigallocatechin-3-gallate (EGCG) complexes as emulsifiers. The physicochemical characteristics and surface morphology of emulsions were mainly characterized by rheological measurements, laser scanning microscope (CLSM) and cryo-scanning electron microscopy (Cryo-SEM). Results indicated that emulsions had dense interfacial layers and strong network structures. As a result, the stability and antioxidant ability of emulsions were improved significantly. In addition, the oxidative stability of emulsions in vitro gastrointestinal digestion was explored. Results showed that emulsions could maintain better oxidative stability owing to antioxidant activity of covalent OSAS-SP-EGCG complexes under gastrointestinal conditions. In particular, lipid hydroperoxide and malondialdehyde contents of emulsions prepared by 1:4 complexes were lower than 0.35 mmol/L and 20.5 nmol/mL, respectively, approximately half those of emulsions stabilized by OSAS (0.65 mmol/L and 39.5 nmol/mL). It was indicated that covalent OSAS-SP-EGCG complexes could effectively inhibit α-linolenic acid oxidation in emulsions during vitro gastrointestinal digestion. This work will provide a theoretical basis for the development of α-linolenic acid emulsions, which will help to broaden application of α-linolenic acid in food industry.

FOXO1 reshapes neutrophils to aggravate acute brain damage and promote late depression after traumatic brain injury

BackgroundNeutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury (TBI). However, the heterogeneity, multifunctionality, and time-dependent modulation of brain damage and outcome mediated by neutrophils after TBI remain poorly understood.MethodsUsing the combined single-cell transcriptomics, metabolomics, and proteomics analysis from TBI patients and the TBI mouse model, we investigate a novel neutrophil phenotype and its associated effects on TBI outcome by neurological deficit scoring and behavioral tests. We also characterized the underlying mechanisms both in vitro and in vivo through molecular simulations, signaling detections, gene expression regulation assessments [including dual-luciferase reporter and chromatin immunoprecipitation (ChIP) assays], primary cultures or co-cultures of neutrophils and oligodendrocytes, intracellular iron, and lipid hydroperoxide concentration measurements, as well as forkhead box protein O1 (FOXO1) conditional knockout mice.ResultsWe identified that high expression of the FOXO1 protein was induced in neutrophils after TBI both in TBI patients and the TBI mouse model. Infiltration of these FOXO1high neutrophils in the brain was detected not only in the acute phase but also in the chronic phase post-TBI, aggravating acute brain inflammatory damage and promoting late TBI-induced depression. In the acute stage, FOXO1 upregulated cytoplasmic Versican (VCAN) to interact with the apoptosis regulator B-cell lymphoma-2 (BCL-2)-associated X protein (BAX), suppressing the mitochondrial translocation of BAX, which mediated the antiapoptotic effect companied with enhancing interleukin-6 (IL-6) production of FOXO1high neutrophils. In the chronic stage, the “FOXO1-transferrin receptor (TFRC)” mechanism contributes to FOXO1high neutrophil ferroptosis, disturbing the iron homeostasis of oligodendrocytes and inducing a reduction in myelin basic protein, which contributes to the progression of late depression after TBI.ConclusionsFOXO1high neutrophils represent a novel neutrophil phenotype that emerges in response to acute and chronic TBI, which provides insight into the heterogeneity, reprogramming activity, and versatility of neutrophils in TBI.

Antioxidant and Hepatoprotective Effects of L-Glu and NAC against CCl4-induced Oxidative Damage in Rats. Biochemical and Histopathological Evaluation

Background: The imbalance between free radical formation and antioxidant defence leads to the development of oxidative stress. The search for substances that would mitigate or prevent the effects of oxidative stress remains relevant. Objective: Our goal was to compare the antioxidant and mitigation effects of L-glutamic acid (LGlu) and N-acetylcysteine (NAC) alone or in combination using a battery of biomarkers of oxidative stress such as reduced glutathione (GSH) superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione transferase (GST) and lipid peroxidation, determined as a content of lipid hydroperoxides (LOOH) and thiobarbituric acid reactive substances (TBARS). Histopathological examination of the liver was also performed. Methods: Experimental rats were divided into five experimental groups. Exp.1: was treated with CCl4 only, Exp. 2: was treated with CCl4/L-Glu, Exp. 3: was treated with CCl4/Glu/NAC. Exp. 4: was treated with CCl4/NAC, Control 5: served as the control rats. Results: These findings suggest that the CCl4 leads to oxidative stress by depleting the antioxidant enzyme activities and increasing peroxidation products. The studied biochemical parameters were altered by the introduction of CCl4, which was normalised (to one degree or another) by L-Glu, LGlu/ NAC and NAC treatment. Conclusion: The most remarkable protective effect was observed in groups of rats that were treated with L-Glu only. This conclusion was confirmed by histopathological findings which showed less severe hepatocellular necrosis, fibrosis and inflammation in CCl4/L- Glu and CCl4/L-Glu/NAC treated group, compared to the CCl4 group.

The effect of nettle extract on antioxidant defense system in piglets after weaning

Background. The effect of common nettle (Urtica dioica L.) extracts on the free radical processes and antioxidant system in piglets during the critical period of weaning from sows has been studied. Materials and Methods. Large white piglets were divided into 2 groups (control and experimental), 9 animals in each. Piglets of the experimental group from 14 days of age and before weaning received the standard diet and the nettle extract in the dose of 6 mg/kg of body weight for 22 days. The blood, as well as erythrocyte hemolysates and plasma of piglets obtained at 14, 36, and 42 days of age, were studied. Results. Our results have shown that weaning causes an oxidative stress in piglets. This state leads to an increase in the concentration of metabolites of free radical damage to protein molecules – carbonyl groups of proteins on the first day and primary products of lipid peroxidation on the seventh day after weaning. This activation of oxidative damage occurs in piglets against the background of a physiologically immature antioxidant system and is characterized by a decrease in the activity of the enzymatic chain – superoxide dismutase, glutathione peroxidase and catalase, as well as the concentration of its non-enzymatic antioxidant – reduced glutathione. Feeding piglets with nettle extract leads to activation of the antioxidant defense system in erythrocytes (higher activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and an increased reduced glutathione level compared to the control values) and a decrease in the concentration of oxidative damage products in the plasma (the content of lipid hydroperoxides, TBA-active products and carbonyl groups of proteins). Conclusion. The positive effect of nettle extract on the inhibition of free radical processes and activation of antioxidant systems indicates that this extract can be added to the standard diet of young animals to increase stress resistance and adaptability of their organism in critical periods of ontogenesis.

Arabinan-rich pectic polysaccharide fraction from Malpighia emarginata fruits alleviates inflammatory pain in mice

Malpighia emarginata (Malpighiaceae), popularly known as “acerola”, is a tropical and subtropical fruit native to the Americas. Despite its high vitamin C content, which gives it a high antioxidant property, soluble dietary fibers, such as polysaccharides, are also abundant constituents of acerola (10% of the dried fruit). The acerola cold-water soluble (ACWS) fraction presented anti-fatigue and antioxidant effects in vivo and in vitro. To infer further systemic effects of ACWS, this study aimed to investigate the antinociceptive, anti-inflammatory, and antioxidant effects of ACWS in murine models of pain. In formalin-induced nociception, ACWS (0.1, 1, and 10 mg/kg) reduced only the inflammatory phase, and also (10 and 30 mg/kg) attenuated the acetic acid-induced writhing and leukocyte migration in the peritoneal cavity. The mechanical allodynia and paw edema induced by intraplantar injection of carrageenan were greatly reduced by ACWS (10 mg/kg). At the inflammatory pick induced by carrageenan (4 h), ACWS significantly reduced myeloperoxidase activity, TNF-α, IL-1β, and PGE2 levels, and restored IL-10 levels. ACWS also exhibited antioxidant properties by decreasing lipid hydroperoxides content, increasing GSH levels, and restoring superoxide dismutase and catalase activities in the carrageenan model and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay. Collectively, these results support the antinociceptive, anti-inflammatory, and antioxidant effects of ACWS and reveal a promising candidate for the treatment of inflammatory pain conditions.

Effects of SGLT2 inhibition on cardiac remodeling and heart failure development in rats with aortic stenosis

Abstract Introduction Aortic stenosis prevalence has been increasing as population ages. Currently, no medical therapies influence the natural history of aortic stenosis. Sodium glucose co-transporter 2 inhibitors (SGLT2i) have reduced heart failure hospitalization and cardiovascular mortality in heart failure patients with both reduced and preserved ejection fraction. The aim of this study was to evaluate the effects of SGLT2 inhibitor empagliflozin (EMPA) on cardiac remodeling and heart failure development in aortic stenosis rats. Methods Eighteen weeks after supra-aortic banding surgery, male Wistar rats were divided in four groups: Sham (n=15); sham + EMPA (Sham-EMPA, n=16); aortic stenosis (AS, n=27); and aortic stenosis + EMPA (AS-EMPA, n=27). Empagliflozin (10 mg/kg/day) was added to rat chow for 8 weeks. Echocardiogram was performed to evaluate cardiac structure and function. Myocardial collagen content was quantified by histology; activity of antioxidant enzymes and enzymes involved in energy metabolism was assessed by spectrophotometry. Protein expression was quantified by Western blot, and matrix metalloproteinase (MMP) activity by zymography. Statistical analysis: ANOVA and Bonferroni or Kruskal-Wallis and Dunn (p&amp;lt;0.05). Results AS-EMPA group had a lower frequency of anatomopathological heart failure features, a lower left ventricular (LV) dilatation (LV diastolic diameter: Sham 8.39±0.57; Sham-EMPA 8.25±0.38; AS 9.80±0.53; AS-EMPA 9.08±0.87 mm; LV systolic diameter: Sham 4.24±0.68; Sham-EMPA 4.19±0.57; AS 5.72±0.74; AS-EMPA 5.09±1.08 mm) and LV mass (Sham 0.85±0.11; Sham-EMPA 0.82±0.07; AS 2.19±0.27; AS-EMPA 1.76±0.34 g), and better diastolic function (isovolumetric relaxation time: Sham 28.6±2.28; Sham-EMPA 29.8±3.04; AS 18.9±2.59; AS-EMPA 22.9±5.02 ms) than AS. Systolic function was impaired in both AS and AS-EMPA compared to their respective controls and did not differ between AS-EMPA and AS. AS and AS-EMPA had larger myocyte diameter, higher interleukin-6 protein expression and lower catalase activity than Sham and Sham-EMPA, respectively. AS and AS-EMPA groups had lower enzyme activity from energy metabolism than their respective controls. AS presented higher lipid hydroperoxide concentration, collagen III and p65 NF-kB protein expression, and lower glutathione peroxidase activity than Sham. AS-EMPA had higher collagen I expression and inactive MMP-2 than Sham-EMPA. AS-EMPA presented higher glutathione peroxidase and intermediary active MMP-2, and lower interstitial collagen fraction (Sham 2.68±0.59; Sham-EMPA 3.16±0.33; AS 5.68±0.97; AS-EMPA 3.55±0.70 %) than AS. Conclusion Empagliflozin improves cardiac remodeling, diastolic function and myocardial oxidative stress, and reduces heart failure feature frequency and interstitial collagen fraction in aortic stenosis rats.

Interaction between Chinese quince fruit proanthocyanidins and soy protein isolate: Effects on physical and oxidative stability of oil-in-water emulsions

Protein-based emulsions are extremely sensitive to droplet aggregation. The interaction between the proanthocyanidins (PAs) and protein can affect the efficacy of protein on the stability of emulsions. In this study, PAs with different molecular weights of ethyl acetate (EA) and retained aqueous (RA) phase were prepared from Chinese quince fruit and mixed with soy protein isolate (SPI) to form complexes, and their effects on the physical and oxidative stability of oil-in-water (O/W) emulsions were assessed. The results confirmed that SPI had fewer α-helices and more random coils when bound to EA and RA. The main forces between PAs and SPI were hydrogen bonds and hydrophobic interactions. Furthermore, RA-SPI, particularly EA-SPI, showed better foaming, emulsifying and antioxidant properties than SPI. The emulsifying activity index values of EA-SPI and RA-SPI were 39.7% and 33.4% higher than that of SPI, respectively. The physical and oxidative stability of O/W emulsions stabilized by SPI were lower than those stabilized by EA-SPI and RA-SPI. At day 15, the lipid hydroperoxide content of EA-SPI and RA-SPI emulsions was 30.5% and 10.3% lower than that of SPI emulsion, respectively. This study provides a basis for PAs as natural antioxidants to improve the stability of O/W emulsions.

Stepwise peroxidation of canola and olive oils: A kinetic study

AbstractKinetics of change in the concentration of lipid hydroperoxides (LOOH) and carbonyls (LCO) were simultaneously investigated during peroxidation of canola and olive oils at 90°C. Depending essentially on the fatty acid compositions, the canola and olive oils exhibited one‐step and two‐step, respectively, multiphase peroxidations before attaining the typical termination phase. Higher and lower rates of the LOOH formation and decomposition, respectively, in the second than in the first step of the canola oil peroxidation were attributed to the dominant peroxidation of linolenic acid in the first step, and the added peroxidation of oleic and linoleic acids in the second step. The kinetics of change in [LCO], which was affected by the potency of constituting antioxidative compounds, indicated that the canola oil would be safe to use till the end of the first peroxidation step whereas the olive oil should be discarded at its induction period.

Kinetics of simultaneous change in the concentration of total lipid hydroperoxides and total conjugated dienes during peroxidation of canola, sunflower, and olive oils

The concentration of total lipid hydroperoxides (LOOH) and total conjugated dienes (CD) were simultaneously monitored during peroxidation of canola, sunflower, and olive oils at 90 °C. Significantly different kinetic parameters differentiating the two analytical variables as a function of the fatty acid compositions as well as the constituting minor components of the oils were obtained. This was attributed to the fact that LOOH represent essentially the fundamental primary oxidation products, including non-conjugated (nCDOOH) and conjugated (CDOOH) diene hydroperoxides, whereas CD stand actually for CDOOH and conjugated diene non-hydroperoxides (CDnOOH) as the primary and secondary, respectively, oxidation products. The simultaneous study on the kinetics of change in [LOOH] and [CD] provided invaluable insights into lipid peroxidation with respect to the different species of conjugated/non-conjugated diene hydroperoxides/non-hydroperoxides.

Metformin Impedes Oxidation of LDL In Vitro.

Metformin is the most commonly prescribed glucose-lowering drug for the treatment of type 2 diabetes. The aim of this study was to investigate whether metformin is capable of impeding the oxidation of LDL, a crucial step in the development of endothelial dysfunction and atherosclerosis. LDL was oxidized by addition of CuCl2 in the presence of increasing concentrations of metformin. The extent of LDL oxidation was assessed by measuring lipid hydroperoxide and malondialdehyde concentrations, relative electrophoretic mobilities, and oxidation-specific immune epitopes. Cytotoxicity of oxLDL in the vascular endothelial cell line EA.hy926 was assessed using the alamarBlue viability test. Quantum chemical calculations were performed to determine free energies of reactions between metformin and radicals typical for lipid oxidation. Metformin concentration-dependently impeded the formation of lipid hydroperoxides, malondialdehyde, and oxidation-specific immune epitopes when oxidation of LDL was initiated by addition of Cu2+. The cytotoxicity of oxLDL was reduced when it was obtained under increasing concentrations of metformin. The quantum chemical calculations revealed that only the reaction of metformin with hydroxyl radicals is exergonic, whereas the reactions with hydroperoxyl radicals or superoxide radical anions are endergonic. Metformin, beside its glucose-lowering effect, might be a suitable agent to impede the development of atherosclerosis and associated CVD. This is due to its capability to impede LDL oxidation, most likely by scavenging hydroxyl radicals.

Acarbose Mitigates Age-Dependent Alterations in Erythrocyte Membrane Transporters During Aging in Rats.

Acarbose (ACA), a well-studied and effective inhibitor of α-amylase and α-glucosidase, is a postprandial-acting antidiabetic medicine. The membrane of the erythrocyte is an excellent tool for analyzing different physiological and biochemical activities since it experiences a range of metabolic alterations throughout aging. It is uncertain if ACA modulates erythrocyte membrane activities in an age-dependent manner. As a result, the current study was conducted to explore the influence of ACA on age-dependent deteriorated functions of transporters/exchangers, disrupted levels of various biomarkers such as lipid hydroperoxides (LHs), protein carbonyl (PCO), sialic acid (SA), total thiol (-SH), and erythrocyte membrane osmotic fragility. In addition to a concurrent increase in Na+/H+ exchanger activity and concentration of LH, PCO, and osmotic fragility, we also detected a considerable decrease in membrane-linked activities of Ca2+-ATPase (PMCA) and Na+/K+-ATPase (NKA), as well as concentrations of SA and -SH in old-aged rats. The aging-induced impairment of the activities of membrane-bound ATPases and the changed levels of redox biomarkers were shown to be effectively restored by ACA treatment.

Unusual multiphase peroxidation of sunflower oil: A kinetic study

Kinetics of change in the concentration of lipid hydroperoxides (LOOH) and carbonyl compounds (LCO) were simultaneously investigated during peroxidation of purified and unpurified sunflower oils at 60 °C. The oils exhibited two distinct peroxidation steps, comprising four alternate initiation and propagation phases, before attaining the typical termination phase. Significantly higher and lower rates of the LOOH formation and decomposition in the second than in the first step, respectively, were attributed to the dominant peroxidation of linoleic acid in the first step, and the remarkably added peroxidation of oleic acid in the second step. On the basis of the kinetics of change in the concentration of LCO, the first peroxidation step was considered to be the crucial one after which commercial sunflower oils should be discarded from sensory and toxicological standpoints.

Destabilization of oil-in-water emulsions: Influences of interfacial assembly of octenyl succinic anhydride starch and chitosan

This study investigated the formation and destabilization of emulsions with different interfacial assemblies of octenyl succinic anhydride starch (OSAS) and chitosan (CS) at critical pH values. All emulsion droplets were connected to each other via bridging of interfacial percolation and observed to form gel network structures during prolonged storage. In addition, partial pH-dependent flocculation occurred during preparation and decreased the degree of coalescence and creaming of emulsions. Compared to bilayer (OSAS-CS and CS-OSAS) emulsions, the complex (OSAS/CS)-stabilized emulsions were more resistant to coalescence, creaming, and lipid oxidation because of their thick interfacial layers (∼2 μm) and tight percolation networks. The layer-by-layer adsorption of OSAS and CS at the interface may lead to reduced homogeneity and stability of the bilayers, making them relatively susceptible to destabilization. Moreover, an appropriate pH (6.0) facilitated the oxidation stability of emulsions by influencing inter-droplet electrostatic interactions. For complex-stabilized emulsions, the lipid hydroperoxide content at pH 6.0 was reduced by approximately 22.85% and 12.26% respectively compared with that at pH 5.5 and pH 6.5. This work may provide promising insights into the rational design of emulsions with desirable stability by combing biopolymers.

Influence of Isolated Resistance Exercise on Cardiac Remodeling, Myocardial Oxidative Stress, and Metabolism in Infarcted Rats.

Exercise is an important therapeutic strategy for preventing and treating myocardial infarction (MI)-induced cardiac remodeling and heart failure. However, the myocardial effects of resistance exercise on infarcted hearts are not completely established. In this study, we investigated the effects of resistance exercise on structural, functional, and molecular cardiac alterations in infarcted rats. Three months after MI induction or simulated surgery, Wistar rats were assigned into three groups: Sham (n = 14); MI (n = 9); and exercised MI (MI-Ex, n = 13). Exercised rats performed, 3 times a week for 12 weeks, four climbs on a ladder with progressive loads. Cardiac structure and left ventricle (LV) function were analyzed by echocardiogram. Myocyte diameters were evaluated in hematoxylin- and eosin-stained histological sections as the smallest distance between borders drawn across the nucleus. Myocardial energy metabolism, lipid hydroperoxide, malondialdehyde, protein carbonylation, and antioxidant enzyme activities were evaluated by spectrophotometry. Gene expressions of NADPH oxidase subunits were evaluated by RT-PCR. Statistical analyses were performed using ANOVA and Tukey or Kruskal-Wallis and Dunn's test. Mortality did not differ between the MI-Ex and MI groups. MI had dilated left atrium and LV, with LV systolic dysfunction. Exercise increased the maximum load-carrying capacity, with no changes in cardiac structure or LV function. Myocyte diameters were lower in MI than in Sham and MI-Ex. Lactate dehydrogenase and creatine kinase activity were lower in MI than in Sham. Citrate synthase and catalase activity were lower in MI and MI-Ex than in Sham. Lipid hydroperoxide concentration was lower in MI-Ex than in MI. Nox2 and p22phox gene expressions were higher in MI-Ex than in Sham. Gene expression of Nox4 was higher in MI and MI-Ex than in Sham, and p47phox was lower in MI than in Sham. Late resistance exercise was safe in infarcted rats. Resistance exercise improved maximum load-carrying capacity, reduced myocardial oxidative stress, and preserved myocardial metabolism, with no changes in cardiac structure or left ventricle function in infarcted rats.

Features of the immune and metabolomic profile in overweight children associated with polymorphic variants of the IL-1B and TP53 genes

Background. The growing number of overweight children is an important problem of modern healthcare. Excess body weight causes the risk of severe metabolic disorders developing. Analysis of changes in the immune, metabolic, and genetic profile of overweight children as markers of the early development of metabolic disorders is an effective tool for the prevention, diagnosis, and treatment of these pathologies.&#x0D; Aim. To identify the features of the immune and metabolomic profile in overweight children aged 711 years associated with polymorphic variants of the IL-1B (rs1143634) and TP53 (rs1042522) genes.&#x0D; Material and methods. 132 children aged 711 years were examined: 54 children with overweight and 78 children with normal body weight. The lymphocytes subpopulation composition was analyzed by flow cytometry; the content of leptin, cortisol, superoxide dismutase, lipid hydroperoxide and interleukin-1 using enzyme immunoassay, immunoglobulin G using the method of radial immunodiffusion method by Mancini. Polymorphic variants of the IL-1B (rs1143634) and TP53 (rs1042522) genes were identified by real-time polymerase chain reaction. Statistical data processing was implemented in the Statistica 10, SNPStat and Gen-Expert programs.&#x0D; Results. The immune profile of the examined children was characterized by an increased content of CD3+CD8+-, CD19+-lymphocytes and immunoglobulin G against the background of CD3+CD4+-lymphocytes, p53 deficiency and a decrease in the number of CD4+/CD8+. The metabolomic profile of children was characterized by an excess content of leptin, cortisol, lipid hydroperoxides, and superoxide dismutase. The identified changes in immune and metabolomic regulation in overweight children were significantly associated with the G allele and GG genotype of the IL-1B gene (rs1143634), as well as with the C allele and CC genotype of the TP53 gene (rs1042522), which cause the initiation of inflammation and inhibition of apoptosis.&#x0D; Conclusion. The established features of immune and metabolomic regulation associated with the G allele and GG genotype of the IL-1B gene (rs1143634) and with the C allele and CC genotype of TP53 gene (rs1042522) represent a complex of markers of overweight formation in children aged 711 years.

Ceruloplasmin Interferes with the Assessment of Blood Lipid Hydroperoxide Content in Small Ruminants.

Simple and inexpensive analytical methods for assessing redox balance in biological matrixes are widely used in animal and human diagnostics. Two of them, reactive oxygen metabolites (ROMs) and total oxidant status (TOS), evaluate the lipid hydroperoxide (LOOH) content of the sample and are based on iron-mediated mechanisms. However, these tests provide uncorrelated results. In this study, we compared these two tests in the blood serum of goat kids and lambs, together with an evaluation of ceruloplasmin (CP) oxidase activity. No significant correlation was found between ROMs and TOS, or between TOS and CP oxidase activity, in either species. Conversely, ROMs and CP oxidase activity were highly correlated in both kid and lamb samples (p < 0.001). A significant progressive reduction in the analytical signal in the ROMs assay was observed when sodium azide, an effective CP inhibitor, was added to the samples before the assay (p < 0.001). This decrease was related to sodium azide concentration (p < 0.01) and was not found when sodium azide was added at the same concentrations in the TOS assay. These findings suggest that ROMs, unlike TOS, may be affected by CP, which interferes with LOOH detection in blood samples.