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The relevance of this study stems from the growing interest in the impact of acute desynchronosis (AD) on oxidative disorders and the insufficiently studied effect of flavonoids on these processes in kidney tissue. This study investigates the effect of quercetin on oxidative and nitrosative stress in rat kidney homogenate under AD and 3 lipopolysaccharide (LPS)-induced systemic inflammatory response (SIR). The animals were randomly divided into five groups: group 1 served as the control, group 2 underwent LPS-induced SIR modeling for 8 weeks, group 3 experienced AD reproduction by shifting the light-dark cycle 6 hours earlier for 7 days, group 4 underwent AD modeling during the last week of LPS-induced SIR, and rats in group 5 were administered a water-soluble form of quercetin (corvitin) intragastrically was administered at a dose of 200 mg/kg (20 mg/kg in terms of quercetin) daily during the AD modeling against LPS-induced SIR. It was found that the modeling of LPS-induced oxidative stress and AD significantly increased the rate of superoxide anion radical production in kidney homogenate by microsomal monooxygenases and NO synthase (NOS), mitochondrial respiratory chain, leukocyte NADPH oxidase, inducible NOS activity, and decreased the activity of the constitutive NOS isoform and its coupling index. Under AD modeling, the rate of superoxide anion radical production by leukocyte NADPH oxidase, total and inducible NOS activity was significantly lower compared with LPS-induced SIR. When modeling AD against the background of LPS-induced SIR, the production of superoxide anion radical by microsomes, mitochondria and leukocyte NADPH oxidase exceeded the respective results of group 2 by 15.9%, 16.0% and 38.5%, and group 3 by 24.4%, 17.5% and 74.6%. The inducible NOS activity was 22.9% higher compared to the value of group 2 and 93.4% higher in group 3, the concentration of peroxynitrites of alkali and alkaline earth metals was 35.5% higher than the respective parameters of group 2 and 57.9% higher than in group 3. Administration of quercetin during AD modeling and LPS-induced oxidative stress significantly reduced the rate of superoxide anion radical production by microsomal monooxygenases by 17.1%, mitochondrial respiratory chain by 31.2%, leukocyte NADPH oxidase by 19.4%, total and inducible NOS activity by 50.4% and 55.5%, respectively; the concentration of peroxynitrites of alkali and alkaline earth metals diminished by 41.4% compared to the value of group 4. It has been concluded that the administration of quercetin significantly reduces the signs of oxidative-nitrosative stress in the kidney homogenate of rats. [ABSTRACT FROM AUTHOR]

This article investigates the impact of water-soluble form of quercetin (corvitin) on the depolymerization of the organic matrix biopolymers and biomechanical properties of the rat mandible following its incomplete fracture during chronic alcohol intoxication. The study was conducted on the 14th day after inducing chronic alcohol intoxication by daily intragastric administration of a 40% ethanol solution in a daily dose of 12 ml/kg body weight; on that day the incomplete fracture of the mandible was modelled by drilling the bone to a depth of 1 mm using a carbide drill with a diameter of 1.5 mm at a speed of up to 1000 rpm. The administration of a water-soluble form of quercetin for 14 days during the posttraumatic period in a daily dose of 10 mg/kg (in recalculation for quercetin), following an incomplete mandibular fracture during chronic alcohol intoxication, significantly reduced the activity of acid phosphatase and its tartrate-resistant isoform by 35.3% and 23.1%, respectively, as well as led to a decrease in the concentration of free hydroxyproline, hexuronic and N-acetylneuraminic acids by 17.0%, 30.6%, and 43.3%, respectively, compared to the findings revealed in animals, which did not receive the drug. The Young's modulus exceeded the values of this group by 72.3%, the elastic limit by 53.2% the tensile strength by 59.6%, and the relative elongation to failure by 30.0%. We concluded that the administration of a water-soluble form of quercetin for 14 days following an incomplete mandibular fracture during chronic alcohol intoxication improves reparative processes in the injured area; it also restricts bone resorption and the depolymerization of connective (bone) tissue biopolymers such as collagen, proteoglycans, and sialoglycoproteins. Under these conditions, the biomechanical properties of the mandibular bone in the fracture area, particularly its elasticity and strength, are significantly enhanced. [ABSTRACT FROM AUTHOR]

The study is aimed at investigating the impact of exogenous melatonin and quercetin on indices of systemic inflammatory response and indicators of carbohydrate and lipid metabolism in the blood serum of male rats exposed to round-the-clock lighting (RCL) with 1500 lx intensity during the last 30 days of being kept on a 60 day high-calorie carbohydrate-lipid diet (HCCLD, 20% fructose solution and the proper chow). The study has demonstrated that the restoration of serum melatonin concentration in rats by its exogenous administration during the RCL exposure and keeping them on HCCLD did not fully correct the indicators of the systemic inflammatory response such as the content of tumor necrosis factor α (TNF-α) and C-reactive protein (CRP), as well as indices of carbohydrate and lipid metabolism such as concentration of insulin, highdensity lipoprotein (HDL), very low-density lipoprotein (VLDL) and triglycerides, HOMA-IR insulin resistance index. The administration of quercetin under the experimental conditions was accompanied by a significant increase in the serum melatonin concentration (by 85.9%), a decrease in the content of TNF-α (by 53.9%), CRP (by 54.4%), glucose (by 49.2%), insulin (by 49.6%), VLDL (by 49, 2%) and triglycerides (by 49.3%), and an increase in HDL concentration (by twofold), but these indicators (with the exception of the HOMA-IR index, which decreased by 62.4%) did not reach the values of the intact group. The combined effect of melatonin and quercetin under RCL exposure and HLLD significantly improved the indicators of systemic inflammatory response, carbohydrate and lipid metabolism that is confirmed by a more significant decrease in serum levels of TNF-α, CRP, insulin, VLDL and triglycerides, an increase in HDL concentration, and a decrease in the HOMA-IR index compared with the separate use of melatonin and quercetin. [ABSTRACT FROM AUTHOR]

This article describes the effect of NF-κB inhibitor ammonium pyrrolidine dithiocarbamate and Nrf2 inducer dimethylfumarate on indicators of oxidative-nitrosative stress in skeletal muscles of rats with chronic hypomelatoninemia, induced by round-the-clock illumination with an intensity of 1500 lux for 30 days, against the background of a carbohydrate-lipid diet (20% fructose solution and appropriate food) for 60 days. The study demonstrated that the administration of ammonium pyrrolidine dithiocarbamate and dimethylfumarate under the experimental conditions impedes the development of hypomelatoninemia, this was accompanied by a two-fold increase in the blood serum melatonin concentration compared to the control group. Moreover, the administration of ammonium pyrrolidine dithiocarbamate and dimethylfumarate significantly reduces the production of superoxide anion radical by electron transport chains of mitochondria (by 47.9 and 51.3%) and sarcoplasmic reticulum (by 48.6 and 52.0%) in the homogenate of femoral muscles, the total activity of NO synthase (by 37.2 and 36.2%) and its inducible isoform (by 41.1 and 40.0%), the concentration of peroxynitrites of alkaline and alkaline earth metals (by 37.2 and 41.0 %), while the activity of constitutive NO-synthases (by 2.9 and 2.8 times) and their conjugation index (by 5.2 and 5.4 times) increases compared to the respective control values. We suggest that modulators of redox-sensitive transcription factors NF-κB and Nrf2 under conditions of chronic hypomelatoninemia and the exposure to the carbohydrate-lipid diet are effective means to restrain the development of oxidative-nitrosative stress in skeletal muscles. [ABSTRACT FROM AUTHOR]

This investigation is aimed at studying the effect of abdominal surgical trauma (laparotomy) on markers of surgical stress and acute phase response as well as markers of carbohydrate and lipid metabolism under lipopolysaccharide (LPS) -induced systemic inflammatory response (SIR). Male Wistar rats were divided into 4 groups: 1st (control) group included "pseudooperated" animals (the procedure included the administration of anesthesia, epilation, fixation of animals, compression of the skin of the abdomen with Mikulicz's clamp by one click); the 2nd group included the rats, which were injected Salmonella typhi (in a dose of 0.4 μg/kg body weight 3 times during the 1st week and once a week for the next 7 weeks) before performing the "false operation"; the 3rd group was made up of the rats after laparotomy; and the 4th group involved the rats after laparotomy performed under LPSinduced SIR. The markers were assessed in 7 days following the "pseudo-operation" or laparotomy. The results obtained have demonstrated the combined effect of laparotomy and LPS-induced SIR was accompanied by a significant increase in the marker of surgical stress, the concentration of cortisol in blood plasma, which significantly exceeded the values of the groups 2 and 3 - by 61.8 and 25.1%, respectively. However, the content of acute-phase protein ceruloplasmin, an acute phase reactant, in the serum remained at the level of the 2nd group. Under these conditions, the concentration of very low-density lipoprotein cholesterol and triglycerides significantly exceeded the relevant values in the 2nd and 3rd groups. The combined effect of surgical trauma and LPS-induced SIR considerably reduced the activity of constitutive isoforms of NO-synthase, which was significantly lower, by 41.7%, than the value in the group 2, and by 41.7% lower than in the group 3. At the same time, the total activity of this enzyme and the activity of its inducible isoform were consistent with the values of the 2nd group. This was accompanied by the development of decompensated lipid peroxidation (with a considerable decrease in the blood antioxidant potential). [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the effects of bioflavonoids, epigallocatechin-3-gallate (EGCG) and quercetin, on the production of reactive oxygen and nitrogen species in the liver of rats under round-the-clock light exposure with an intensity of 1500 lux for 30 days while being kept on carbohydrate-lipid diet (20% fructose solution and appropriate food) for 60 days. In the liver tissues, the rate of the superoxide anion production by NADPH-dependent electron transport chains (microsomal monooxygenases and constitutive uncoupled NO synthases) increased by 1.93 times, by the mitochondrial respiratory chain by 1.89 times, and it was doubled by leukocyte NADPH-oxidase. The total activity of NO synthase was increased by 2.35 times, the activity of its inducible isoform increased by 2.57 times, and the concentration of alkali and alkaline earth metals peroxynitrites elevated by 1.68 times. Administration of bioflavonoids-epigallocatechin-3-gallate and quercetinsignificantly restrained the rate of superoxide anion production in the liver tissues by microsomal monooxygenases and NO synthase by 39.1 and 40.1%, by the mitochondrial respiratory chain by 37.2 and 34.4%, by leukocyte NADPH-oxidase by 35.0 and 32.1%, respectively. Epigallocatechin-3-gallate and quercetin inhibited the total activity of NO-synthase by 46.7 and 36.2%, the activity of its inducible isoform by 49.6 and 39,0%, increased the activity of the constitutive isoenzyme NO-synthase by 2.9 times and its coupling index by 4.5 and 4.7 times. Additionally, administration of these bioflavonoids lowered the concentration of peroxynitrites of alkali and alkaline earth metals by 30.5 and 34.3% compared to the respective values obtained in the group of rats, which did not receive the bioflavonoids, but were exposed to light and carbohydrate-lipid-rich diet. We suggest that epigallocatechin-3-gallate and quercetin in the above experimental conditions are effective means to restrain the formation of reactive oxygen and nitrogen species in the liver tissue. [ABSTRACT FROM AUTHOR]

Copyright of Physiological Journal / Fiziologichnyi Zhurnal is the property of O.O. Bogomoletz Institute of Physiology of the National Academy of Sciences of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Physiological Journal / Fiziologichnyi Zhurnal is the property of O.O. Bogomoletz Institute of Physiology of the National Academy of Sciences of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Physiological Journal / Fiziologichnyi Zhurnal is the property of O.O. Bogomoletz Institute of Physiology of the National Academy of Sciences of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This experiment was aimed at studying the effect of combined action produced by L-arginine and water-soluble form of quercetin (corvitin) on the markers of oxidative-nitrosative stress in the skin under 30-day intoxication with sodium nitrate (200 mg/kg per day). The combined intraperitoneal administration of L-arginine (500 mg/kg) and corvitin (10 mg / kg in terms of quercetin), once every three days starting from the 15th day of intoxication, reduced the formation of peroxynitrite, production of superoxide anion radical (.О-2) by NADPH-dependent (endoplasmic reticulum and NO-synthase) and NADH-dependent (mitochondrial) electron transport chains in the skin tissues, decreased the concentration of compounds reacting with thiobarbituric acid products during incubation in the prooxidant iron-ascorbate buffer solution. The values of these indicators were significantly inferior to the corresponding data obtained by the separate administration of these substances. The combined effect of L-arginine and quercetin in the experimental conditions increased the activity of arginase and superoxide dismutase in the skin tissues, that significantly exceeded the results of the series, in which above mentioned compounds were used separately. We can conclude the combined administration of L-arginine and corvitin is more effective in preventing oxidative-nitrosative stress in the skin of rats exposed to excessive intake of sodium nitrate compared with their separate application, and reduces the production of reactive oxygen and nitrogen species (.О-2 and peroxynitrite), increases the antioxidant potential, and enhances the activity of arginase and superoxide dismutase. [ABSTRACT FROM AUTHOR]