Pro-oxidant Enzymes Research Articles

Overexpression of Cpg15 Alleviates the Oxidative Stress in Neuronal Cells Via Regulating Redox Enzymes and Nrf2 Antioxidative Pathway.

Oxidative stress is becoming increasingly implicated in the development of a variety of neurological disorders. However, the underlying mechanism remains elusive. In the present study, we investigated the function and related signal pathway which Cpg15, a neuronal-specific expressed neurotrophic factor, plays in the oxidative stress of neurons using a H2O2-treated N2a cell model. The results showed that the Cpg15 expression was decreased under oxidative stress, and overexpression of Cpg15 increased the activity of antioxidative SOD enzymes and decreased the expression level of prooxidative COX2 enzyme, and the level of oxidative products malondialdehyde (MDA), indicating its function and potential mechanism in alleviating the oxidative stress of cells. The results also indicated that the Nrf2/HO-1 antioxidative pathway was involved in the Cpg15-mediated alleviation of oxidative stress. Also, overexpression of Cpg15 activated the Nrf2 antioxidative pathway in the thalamus of the REM sleep-deprived mice. In conclusion, our results implied that supplemental expression of Cpg15 may alleviate oxidative stress in neuronal cells via regulating the redox enzymes or activating the Nrf2 antioxidant pathway.

Insights into antiradical mechanism and pro-oxidant enzyme inhibitor activity of walterolactone A/B 6-O-gallate-β-d-pyranoglucoside originating from Euonymus laxiflorus Champ. using in silico study.

The ability of a new compound, Wal, (walterolactone A/B 6-O-gallate-β-d-pyranoglucoside) originating from Euonymus laxiflorus Champ. as a hydroperoxyl radical scavenger and pro-oxidant enzyme inhibitor was studied in silico. Different mechanisms, reaction locations, and chemical species of Wal in aqueous solution were taken into consideration. Formal hydrogen transfer from the OH group has been discovered as the chemical process that contributes most to the antioxidant properties of Wal in nonpolar and aqueous solutions. The overall rate coefficients for polar and non-polar environments are expected to have values of 7.85 × 106 M-1 s-1 and 4.84 × 105 M-1 s-1, respectively. According to the results of the investigation, Wal has greater scavenging activity against the HOO˙ radical than the reference antioxidant Trolox at physiological pH (7.4). In addition, docking results indicate that Wal's antioxidant properties involve the inhibition of the activity of enzyme families (CP450, MP, NO, and XO) that are responsible for ROS production.

Flavonoid Compounds of Buah Merah (Pandanus conoideus Lamk) as a Potent Oxidative Stress Modulator in ROS-induced Cancer: In Silico Approach

Buah Merah, a typical fruit from Papua, Indonesia which is used empirically in cancer therapy is rich in carotenoids and flavonoids. However, the mechanisms by which Buah Merah ameliorates cancer remained unknown. Natural antioxidant enzymes and pro-oxidant enzymes modulation significantly suppressed ROS production and cancer growth. Therefore, the determination of target enzymes of Buah Merah contents was studied through an in silico approach. Carotenoid and flavonoid compounds from Buah Merah were docked to 7 ROS modulating enzymes using Autodock Vina and the interaction stability was studied using the CABS Flex 2.0 server. The crucial amino acids of each enzyme were determined using DockFlin and prediction of acute oral toxicity of each test ligand was studied using ProTox-II. Based on the molecular docking results, quercetin 3'-glucoside is the most potent compound in binding to CAT, GR, GPx, SOD, LOX, and NOX with binding energy values of -11.2, -9.7, -8.6, -10.2, -10.7, and -12.8 kcal/mol, respectively. Meanwhile, taxifolin 3-O-α-arabinopyranose produced the highest binding affinity of -10.0 kcal/mol at the XO. Each test ligand formed stable interactions with ROS modulating enzymes and formed bonds with crucial amino acids resulting in strong adhesion compared to native and reference ligands. The glucoside group of quercetin 3'-glucoside plays an essential role in determining the proper position in the attachment and supports the formation of hydrogen bonds with receptors. With low acute oral toxicity, it can be concluded that quercetin 3'-glucoside from Buah Merah is a potent oxidative stress modulator in cancer prevention and therapy.

Protective Effects of Carnosic Acid on Lipopolysaccharide-Induced Acute Kidney Injury in Mice.

Septic acute kidney injury (AKI) is an important medical problem worldwide, but current treatments are limited. During sepsis, lipopolysaccharide (LPS) activates various signaling pathways involved in multiorgan failure. Carnosic acid is a natural phenolic diterpene and has multiple bioactivities, such as anti-tumor, anti-inflammatory, and anti-oxidative effects. However, the effect of carnosic acid on septic AKI has not been explored. Therefore, this study aimed to determine whether carnosic acid has a therapeutic effect on LPS-induced kidney injury. Administration of carnosic acid after LPS injection ameliorated histological abnormalities and renal dysfunction. Cytokine production, immune cell infiltration, and nuclear factor-κB activation after LPS injection were also alleviated by carnosic acid. The compound suppressed oxidative stress with the modulation of pro-oxidant and antioxidant enzymes. Tubular cell apoptosis and caspase-3 activation were also inhibited by carnosic acid. These data suggest that carnosic acid ameliorates LPS-induced AKI via inhibition of inflammation, oxidative stress, and apoptosis and could serve as a useful treatment agent for septic AKI.

Nephroprotective Effects of Synthetic Flavonoid Hidrosmin in Experimental Diabetic Nephropathy.

Diabetes mellitus (DM) is a high-impact disease commonly characterized by hyperglycemia, inflammation, and oxidative stress. Diabetic nephropathy (DN) is a common diabetic microvascular complication and the leading cause of chronic kidney disease worldwide. This study investigates the protective effects of the synthetic flavonoid hidrosmin (5-O-(beta-hydroxyethyl) diosmin) in experimental DN induced by streptozotocin injection in apolipoprotein E deficient mice. Oral administration of hidrosmin (300 mg/kg/day, n = 11) to diabetic mice for 7 weeks markedly reduced albuminuria (albumin-to-creatinine ratio: 47 ± 11% vs. control) and ameliorated renal pathological damage and expression of kidney injury markers. Kidneys of hidrosmin-treated mice exhibited lower content of macrophages and T cells, reduced expression of cytokines and chemokines, and attenuated inflammatory signaling pathways. Hidrosmin treatment improved the redox balance by reducing prooxidant enzymes and enhancing antioxidant genes, and also decreased senescence markers in diabetic kidneys. In vitro, hidrosmin dose-dependently reduced the expression of inflammatory and oxidative genes in tubuloepithelial cells exposed to either high-glucose or cytokines, with no evidence of cytotoxicity at effective concentrations. In conclusion, the synthetic flavonoid hidrosmin exerts a beneficial effect against DN by reducing inflammation, oxidative stress, and senescence pathways. Hidrosmin could have a potential role as a coadjutant therapy for the chronic complications of DM.

Myeloperoxidase and Paraoxonase Activity in Acute Coronary Syndrome Patients

Background: Myeloperoxidase (MPO), an oxidative stress related enzyme is elevated in Coronary Artery Disease (CAD) and is involved in development of atherosclerotic plaque. Paraoxonase (PON) an enzyme protein associated with HDL serves as an antioxidant and plays an important role in preventing the formation of Oxidized LDL (OxLDL). This suggests a conflicting role of MPO and PON in development of cardiovascular disease and atherosclerosis.
 Aim: Present study was done to evaluate and compare MPO/PON ratio in Acute Coronary Syndrome (ACS) patients with controls. The study evaluates and compares the pro oxidant and pro inflammatory enzyme, MPO and anti-oxidant and anti-inflammatory enzyme, PON in ACS patients with controls. Oxidative marker, Malondialdehyde (MDA) and anti-oxidant marker, Reduced Glutathione (GSH) was assessed in ACS patients and compared with controls. An attempt was also made to correlate MPO/PON ratio to markers of oxidative stress (MDA and GSH).
 Methods: Cross-sectional study carried out in Dr. Somervell Memorial CSI Medical College, Trivandrum, Kerala, India.50 ACS patients from Cardiac Care Unit and 50 age and sex matched controls without CAD from Medical College Health Checkup was selected.
 Results: MPO and MPO/PON ratio were significantly high and PON was significantly lower in ACS patients compared to controls. Total cholesterol, Triglyceride, LDL, MDA were significantly high in ACS patients. Statistically significant positive correlation was observed between MPO/PON and MDA. Significant negative correlation was observed between MPO/PON and GSH.
 Conclusion: Myeloperoxidase and MPO/PON ratio was significantly high in ACS patients than controls. This is suggestive of the role of MPO in oxidative damage to lipoproteins in CAD patients. Prooxidant, Paraoxonase ,and antioxidant, GSH is lowered in ACS patients as a result of the increased oxidative stress. This study suggests that MPO/PON1 ratio can be used as a predictive marker of ACS.

Curcumin analogues with improved antioxidant properties: A theoretical exploration

Curcumin, a ubiquitous dietary molecule, is a versatile antioxidant that fights against free radicals. The antioxidant activity of curcumin and its structural analogues such as hispolon, halfcurcumin and polyhydroxycurcumin is analyzed using density functional theory (DFT). The thermochemical parameter, bond dissociation enthalpy (BDE) is used to analyse the propensity of radical attack. The hydrogen atom transfer (HAT) energetics for the hydroxyl groups of the antioxidant molecules with •OH and •OOH in both gas and solvent media are explored. Based on ourresults, hispolon and polyhydroxycurcumin characterized by multiple hydroxyl groups arranged in ortho dihydroxy fashion are good radical scavengers. Halfcurcumin exhibited comparatively similar activity as that of curcumin. The absorption properties of these molecules are in good agreement with the reported experimental findings. The molecular docking studies revealed that these antioxidants can indirectly control the oxidative stress by favourably interacting with the pro-oxidant enzyme like xanthine oxidase.

Disturbed Lipid Metabolism in Diabetic Patients with Manifest Coronary Artery Disease Is Associated with Enhanced Inflammation.

Background: Diabetic vasculopathy plays an important role in the pathophysiology of coronary artery disease (CAD) with oxidative stress as a strong mediator. This study aims to elucidate the underlying pathomechanisms of diabetic cardiac vasculopathy leading to coronary disease with an emphasis on the role of oxidative stress. Therefore, novel insights into antioxidant pathways might contribute to new strategies in the treatment and prevention of diabetic CAD. Methods: In 20 patients with insulin-dependent or non-insulin dependent diabetes mellitus (IDDM/NIDDM) and 39 non-diabetic (CTR) patients, myocardial markers of oxidative stress, vasoactive proteins, endothelial nitric oxide synthase (eNOS), activated phosphorylated eNOS (p-eNOS), and antioxidant enzymes, e.g., tetrahydrobiopterin generating dihydrofolate reductase (DHFR), heme oxygenase (HO-1), as well as serum markers of inflammation, e.g., E-selectin, interleukin-6 (IL-6), and lipid metabolism, e.g., high- and low-density lipoptrotein (HDL- and LDL-cholesterol) were determined in specimens of right atrial tissue and in blood samples from type 2 diabetic and non-diabetic patients undergoing coronary artery bypass graft (CABG) surgery. Results: IDDM/NIDDM increased markers of inflammation (e.g., E-selectin, p = 0.005 and IL-6, p = 0.051), decreased the phosphorylated myocardial p-eNOS (p = 0.032), upregulated the myocardial stress response protein HO-1 (p = 0.018), and enhanced the serum LDL-/HDL-cholesterol ratio (p = 0.019). However, the oxidative stress markers in the myocardium and the expression of vasoactive proteins (eNOS, DHFR) showed only marginal adverse changes in patients with IDDM/NIDDM. Conclusion: Dyslipidemia and myocardial inflammation seem to be the major determinants of diabetic CAD complications. Dysregulation in pro-oxidative enzymes might be attributable to the severity of CAD and oxidative stress levels in all included patients undergoing CABG.

Inhibition of 11β-HSD1 Ameliorates Cognition and Molecular Detrimental Changes after Chronic Mild Stress in SAMP8 Mice.

Impaired glucocorticoid (GC) signaling is a significant factor in aging, stress, and neurodegenerative diseases such as Alzheimer’s disease. Therefore, the study of GC-mediated stress responses to chronic moderately stressful situations, which occur in daily life, is of huge interest for the design of pharmacological strategies toward the prevention of neurodegeneration. To address this issue, SAMP8 mice were exposed to the chronic mild stress (CMS) paradigm for 4 weeks and treated with RL-118, an 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitor. The inhibition of this enzyme is linked with a reduction in GC levels and cognitive improvement, while CMS exposure has been associated with reduced cognitive performance. The aim of this project was to assess whether RL-118 treatment could reverse the deleterious effects of CMS on cognition and behavioral abilities and to evaluate the molecular mechanisms that compromise healthy aging in SAMP8 mice. First, we confirmed the target engagement between RL-118 and 11β-HSD1. Additionally, we showed that DNA methylation, hydroxymethylation, and histone phosphorylation were decreased by CMS induction, and increased by RL-118 treatment. In addition, CMS exposure caused the accumulation of reactive oxygen species (ROS)-induced damage and increased pro-oxidant enzymes—as well as pro-inflammatory mediators—through the NF-κB pathway and astrogliosis markers, such as GFAP. Of note, these modifications were reversed by 11β-HSD1 inhibition. Remarkably, although CMS altered mTORC1 signaling, autophagy was increased in the SAMP8 RL-118-treated mice. We also showed an increase in amyloidogenic processes and a decrease in synaptic plasticity and neuronal remodeling markers in mice under CMS, which were consequently modified by RL-118 treatment. In conclusion, 11β-HSD1 inhibition through RL-118 ameliorated the detrimental effects induced by CMS, including epigenetic and cognitive disturbances, indicating that GC-excess attenuation shows potential as a therapeutic strategy for age-related cognitive decline and AD.

Beneficial Effects of High Intensity Interval Training and/or Linseed Oil Supplementation to Limit Obesity-Induced Oxidative Stress in High Fat Diet-Fed Rats.

High-intensity interval training (HIIT) and linseed oil (LO) supplementation are effective strategies to reduce obesity-induced oxidative stress. Our aim was to determine whether the HIIT + LO combination prevents obesity-induced oxidative stress in high fat diet (HFD)-fed rats. HFD-fed 8-week-old, male, Wistar rats were subdivided in four groups: HFD, LO (2% of sunflower oil replaced with 2% of LO in the HFD), HIIT (4 days/week for 12 weeks), and HIIT + LO. Wistar rats fed a low-fat diet (LFD) were used as controls. Epididymal and subcutaneous adipose tissue, gastrocnemius muscle, liver, and plasma samples were collected to measure oxidative stress markers (AOPP, oxLDL), antioxidant (SOD, CAT, and GPx activities) and pro-oxidant (NOx and XO) enzyme activities. Compared with the LFD, the HFD altered the pro/antioxidant status in different tissues (increase of AOPP, oxLDL, SOD and catalase activities in plasma, and SOD activity increase in liver and decrease in adipose tissues) but not in gastrocnemius. LO upregulated CAT activity and decreased NOx in liver. HIIT alleviated HFD negative effects in liver by reducing SOD and NOx activities. Moreover, the HIIT + LO combination potentiated SOD activity upregulation in subcutaneous tissue. HIIT and LO supplementation have independent beneficial effects on the pro/antioxidant balance. Their association promotes SOD activity in subcutaneous adipose tissue.

Protective Effects of 6-Shogaol, an Active Compound of Ginger, in a Murine Model of Cisplatin-Induced Acute Kidney Injury.

Acute kidney injury (AKI) is a dose-limiting side effect of cisplatin therapy in cancer patients. However, effective therapies for cisplatin-induced AKI are not available. Oxidative stress, tubular cell death, and inflammation are known to be the major pathological processes of the disease. 6-Shogaol is a major component of ginger and exhibits anti-oxidative and anti-inflammatory effects. Accumulating evidence suggest that 6-shogaol may serve as a potential therapeutic agent for various inflammatory diseases. However, whether 6-shogaol exerts a protective effect on cisplatin-induced renal side effect has not yet been determined. The aim of this study was to evaluate the effect of 6-shogaol on cisplatin-induced AKI and to investigate its underlying mechanisms. An administration of 6-shogaol after cisplatin treatment ameliorated renal dysfunction and tubular injury, as shown by a reduction in serum levels of creatinine and blood urea nitrogen and an improvement in histological abnormalities. Mechanistically, 6-shogaol attenuated cisplatin-induced oxidative stress and modulated the renal expression of prooxidant and antioxidant enzymes. Apoptosis and necroptosis induced by cisplatin were also suppressed by 6-shogaol. Moreover, 6-shogaol inhibited cisplatin-induced cytokine production and immune cell infiltration. These results suggest that 6-shogaol exhibits therapeutic effects against cisplatin-induced AKI via the suppression of oxidative stress, tubular cell death, and inflammation.

Prenylcysteine oxidase 1, an emerging player in atherosclerosis

The research into the pathophysiology of atherosclerosis has considerably increased our understanding of the disease complexity, but still many questions remain unanswered, both mechanistically and pharmacologically. Here, we provided evidence that the pro-oxidant enzyme Prenylcysteine Oxidase 1 (PCYOX1), in the human atherosclerotic lesions, is both synthesized locally and transported within the subintimal space by proatherogenic lipoproteins accumulating in the arterial wall during atherogenesis. Further, Pcyox1 deficiency in Apoe-/- mice retards atheroprogression, is associated with decreased features of lesion vulnerability and lower levels of lipid peroxidation, reduces plasma lipid levels and inflammation. PCYOX1 silencing in vitro affects the cellular proteome by influencing multiple functions related to inflammation, oxidative stress, and platelet adhesion. Collectively, these findings identify the pro-oxidant enzyme PCYOX1 as an emerging player in atherogenesis and, therefore, understanding the biology and mechanisms of all functions of this unique enzyme is likely to provide additional therapeutic opportunities in addressing atherosclerosis.

Theoretical Study of Radical Inactivation, LOX Inhibition, and Iron Chelation: The Role of Ferulic Acid in Skin Protection against UVA Induced Oxidative Stress.

Ferulic acid (FA) is used in skin formulations for protection against the damaging actions of the reactive oxygen species (ROS) produced by UVA radiation. Possible underlying protective mechanisms are not fully elucidated. By considering the kinetics of proton-coupled electron transfer (PCET) and radical-radical coupling (RRC) mechanisms, it appears that direct scavenging could be operative, providing that a high local concentration of FA is present at the place of •OH generation. The resulting FA phenoxyl radical, after the scavenging of a second •OH and keto-enol tautomerization of the intermediate, produces 5-hydroxyferulic acid (5OHFA). Inhibition of the lipoxygenase (LOX) enzyme, one of the enzymes that catalyse free radical production, by FA and 5OHFA were analysed. Results of molecular docking calculations indicate favourable binding interactions of FA and 5OHFA with the LOX active site. The exergonicity of chelation reactions of the catalytic Fe2+ ion with FA and 5OHFA indicate the potency of these chelators to prevent the formation of •OH radicals via Fenton-like reactions. The inhibition of the prooxidant LOX enzyme could be more relevant mechanism of skin protection against UVA induced oxidative stress than iron chelation and assumed direct scavenging of ROS.

Oxidative Stress Does Not Influence Subjective Pain Sensation in Inflammatory Bowel Disease Patients.

Oxidative stress (OS) has been proposed as a significant causative and propagating factor in inflammatory bowel diseases (IBDs). Modulation of OS is possible through antioxidants and inhibition of oxidizing enzymes. Thirty-one IBD patients and thirty-two controls were included in the study. The aim was to examine the levels of OS in colonic tissue of IBD requiring surgical intervention and control group, and their association with pain intensity. Total antioxidant capacity (TAC), superoxide dismutase (SOD) and catalase (CAT) activity, glutathione (GSH) and oxidized glutathione (GSSG) levels, and glutathione peroxidase (GPX) activity as markers of antioxidant defense were determined. Cyclooxygenases activities (Total COX, COX-1 and COX-2) were measured as prooxidant enzymes. Thiobarbituric acid reactive substances (TBARS) concentrations were measured to evaluate lipid peroxidation. Disease activity was assessed, and each subject filled out VAS and Laitinen’s pain assessment scales. Correlation between the OS, pain intensity, disease activity parameters, C-reactive protein (CRP), number of stools passed daily, disease duration, and dietary habits was investigated. No TAC differences were found between the groups. A significant decrease of SOD activity and GSH and GSSG levels was seen in IBD patients vs. controls, while GPX activity was diminished significantly only in CD patients. CAT and COX-1 activity was increased, and COX-2 significantly decreased in IBD. TBARS were significantly higher in CD patients compared to control group. No correlation was found between pain scores, inflammatory status, disease activity, disease duration, or dietary habits and OS markers. In our study, OS did not influence pain sensation reported by IBD patients.

Effects of Juglone on Neutrophil Degranulation and Myeloperoxidase Activity Related to Equine Laminitis.

Experimental laminitis, characterized by a failure of the dermal–epidermal interface of the foot, can be induced in horses by the oral administration of a black walnut extract (BWE). In the early phase of this severe and painful disease, an activation of neutrophil occurs, with the release of myeloperoxidase (MPO), a pro-oxidant enzyme of neutrophils, in plasma, skin, and laminar tissue. Juglone, a naphthoquinone derivative endowed with redox properties, is found in walnuts and has been incriminated in this neutrophil activation. We report for the first time the inhibitory activity of juglone on the degranulation of neutrophils induced by cytochalasin B and formyl-methionyl-leucyl-phenylalanine as monitored by the MPO release (>90% inhibition for 25 and 50 μM). Moreover, it also acts on the peroxidase activity of MPO by interacting with the intermediate “π cation radical,” as evidenced by the classical and specific immunological extraction followed by enzymatic detection (SIEFED) assays. These results are confirmed by a docking study showing the perfect positioning of juglone in the MPO enzyme active site and its interaction with one of the amino acids (Arg-239) of MPO apoprotein. By chemiluminescence and electron paramagnetic resonance techniques, we demonstrated that juglone inhibited reactive oxygen species (ROS) and superoxide anion free radical produced from phorbol myristate acetate (PMA)-activated polymorphonuclear neutrophils (PMNs). These results indicate that juglone is not the trigger for equine laminitis, at least if we focus on the modulation of neutrophil activation.

Aged Mice Devoid of the M3 Muscarinic Acetylcholine Receptor Develop Mild Dry Eye Disease.

The parasympathetic nervous system is critically involved in the regulation of tear secretion by activating muscarinic acetylcholine receptors. Hence, various animal models targeting parasympathetic signaling have been developed to induce dry eye disease (DED). However, the muscarinic receptor subtype (M1–M5) mediating tear secretion remains to be determined. This study was conducted to test the hypothesis that the M3 receptor subtype regulates tear secretion and to evaluate the ocular surface phenotype of mice with targeted disruption of the M3 receptor (M3R−/−). The experimental techniques included quantification of tear production, fluorescein staining of the ocular surface, environmental scanning electron microscopy, assessment of proliferating cells in the corneal epithelium and of goblet cells in the conjunctiva, quantification of mRNA for inflammatory cytokines and prooxidant redox enzymes and quantification of reactive oxygen species. Tear volume was reduced in M3R−/− mice compared to age-matched controls at the age of 3 months and 15 months, respectively. This was associated with mild corneal epitheliopathy in the 15-month-old but not in the 3-month-old M3R−/− mice. M3R−/− mice at the age of 15 months also displayed changes in corneal epithelial cell texture, reduced conjunctival goblet cell density, oxidative stress and elevated mRNA expression levels for inflammatory cytokines and prooxidant redox enzymes. The findings suggest that the M3 receptor plays a pivotal role in tear production and its absence leads to ocular surface changes typical for DED at advanced age.

Raspberry Consumption Decreases NOX4 Expression and Increases Antioxidant Enzymes in Lungs of Angiotensin II-Infused Rats

Abstract Objectives To determine whether a diet supplemented with red raspberry (RB) is effective at reducing angiotensin (Ang) II-induced oxidative stress in the lungs of Sprague Dawley (SD) rats. Methods Eight-week-old male SD rats were fed an AIN-93M diet alone (control and Ang II) or supplemented with 10% w/w freeze-dried RB powder for a total of seven weeks. At week 4, SD rats were implanted with subcutaneous osmotic minipumps for delivery of 0.9% saline (control) or Ang II (270 ng/kg body weight/day). Following 3 weeks of infusion, rats were sacrificed, and lungs were collected for analysis. Protein expression of the pro-oxidant enzyme, NADPH oxidase (NOX) 4, and antioxidant enzymes superoxide dismutase 1 (SOD1), catalase, heme oxygenase-1 (HO-1), and NADPH quinone dehydrogenase 1 (NQO1) were assessed by western blot. Results were analyzed by one-way ANOVA followed by Tukey post-hoc test. Results were normalized to control and presented as means ± standard deviation. Results RB supplementation significantly increased the expression of antioxidant enzymes, including, SOD1 (1.34 ± 0.16, n = 5, vs 1.11 ± 0.13-fold, n = 5, P = 0.04) and catalase (1.50 ± 0.28, n = 5, vs 0.79 ± 0.20-fold, n = 5, P = 0.008), when compared to Ang II alone. Compared to control, however, RB significantly increased SOD1 (1.00 ± 0.05-fold, n = 4, P = 0.004) while catalase did not (1.00 ± 0.40, n = 4, P = 0.07). Similarly, HO-1 (1.66 ± 0.82, n = 5, vs 0.75 ± 0.13-fold, n = 4, P = 0.046) and NQO1 (2.13 ± 0.19, n = 4, vs 1.26 ± 0.14-fold, n = 5, P < 0.0001) were greater in the RB supplemented rats in comparison to Ang II alone. Additionally, RB significantly increased NQO1 (1.00 ± 0.16, n = 4, P < 0.0001) but not HO-1 (1.00 ± 0.43-fold, n = 4, P = 0.22) when compared to control. RB supplementation also decreased the expression of NOX4 (0.77 ± 0.38, n = 5, vs 1.41 ± 0.30-fold, n = 5, P = 0.02) in comparison to Ang II alone. Conclusions Our results suggest the potential for red raspberries to decrease oxidative stress within the lung tissue. As investigations into whole food dietary treatments in lung conditions are essentially non-existent, future work will aim to determine the potential for raspberries to serve as a complementary therapy in these conditions. Funding Sources This work was funded by the Agriculture and Food Research Initiative (grant no. 2019–67,017-29,257/project accession no. 1,018,642) from the USDA National Institute of Food and Agriculture.

N-acetylcysteine supplementation did not reverse mitochondrial oxidative stress, apoptosis, and inflammation in the salivary glands of hyperglycemic rats

Background/objectivesPrevious studies have shown that N-acetylcysteine (NAC) supplementation with the simultaneous inclusion of HFD prevents salivary glands from oxidative stress and mitochondrial dysfunction. In this experiment, we examined if NAC supplementation could reverse the harmful effect of HFD on mitochondrial function, reduce the severity of apoptosis, and the activity of pro-oxidative enzymes in the salivary glands of rats with confirmed hyperglycemia.Subjects/methodsWistar rats were fed the standard or high-fat (HFD) diet for 10 weeks. After 6 weeks of the experiment, HFD rats were diagnosed with hyperglycemia and for the next 4 weeks, the animals were given NAC intragastrically. In the mitochondrial fraction of the parotid (PG) and submandibular salivary glands (SMG), we assessed redox status, inflammation, and apoptosis.ResultsThe inclusion of NAC increased the activity of mitochondrial complexes I and II + III as well as decreased the concentration of interleukin-1β, tumor necrosis factor α, and caspase-3, but only in the parotid glands of rats with hyperglycemia compared to the HFD group. However, N-acetylcysteine supplementation did not reduce the activity of caspase-9 or the Bax/Bcl-2 ratio in PG and SMG mitochondria. In both salivary glands we observed reduced activity of cytochrome c oxidase, NADPH oxidase, and xanthine oxidase, as well as hindered production of ROS and lower ADP/ATP radio, but the levels of these parameters were not comparable to the control group.ConclusionsWe demonstrated that NAC supplementation restores the glutathione ratio only in the mitochondria of the submandibular salivary glands. The supply of NAC did not significantly affect the other measured parameters. Our results indicate that NAC supplementation provides little protection against free radicals, apoptosis, and inflammation in the salivary gland mitochondria of HFD rats. Stimulated salivary secretion in hyperglycaemic rats supplemented with NAC seems to be closely related to mitochondrial respiratory capacity and appropriate ATP level.

FC 087MIR-155/SOCS1 REGULATORY LOOP INFLUENCES DIABETIC KIDNEY DISEASE BY JAK/STAT PATHWAY MODULATION

Abstract Background and Aims Diabetic nephropathy is the leading cause of chronic kidney disease worldwide. Hyperglycemia in concert with cytokines activate Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway and induce gene expression of many inflammatory and oxidative stress mediators, which are critical events at all stages of diabetic kidney disease. Suppressor of cytokine signaling 1 (SOCS1) is a STAT-inducible protein and a negative feedback regulator of JAK/STAT pathway. The microRNA-155 is an epigenetic modulator of SOCS1 gene by repressing its translation and, at the same time, is a transcriptional target of STAT, thus completing another regulatory loop of JAK/STAT pathway. Therefore, our aim was to explore the interplay between miR-155 and JAK/STAT/SOCS1 axis in experimental diabetic nephropathy. Method In streptozotocin-induced type 1 diabetic aged mice (wild-type and apolipoprotein E (apoE) knockout) we analyzed the kidney levels of miR-155 and markers of renal damage, inflammation and oxidative stress. In vitro, the expression of miR-155, SOCS1 and STAT1 in mesangial, tubuloepithelial and macrophage cell lines were modulated by silencing/inhibition or overexpression/mimicking experiments to further determine the JAK/STAT pathway activation and expression of downstream target genes. Results In vivo, type 1 diabetes significantly upregulated miR-155 expression in kidneys from both wild-type and apoE knockout mice (1.8- and 4.5-fold vs respective non-diabetic controls). The miR-155 levels directly correlated with parameters of renal damage (serum creatinine, albuminuria, kidney-to-body weight ratio and renal score) and the mRNA expression of chemokines (Ccl2 and Ccl5) and pro-oxidant enzymes (Nox2 and Nox4), but inversely with antioxidant genes (Sod1 and Cat). In vitro, the expression of miR-155 was increased in renal cells and macrophages exposed to hyperglycemia and/or inflammatory conditions. Overexpression of miR-155 reduced SOCS1 expression, enhanced STAT1 and STAT3 activation and pro-inflammatory cytokines and chemokines (Il6, Tnfa, Ccl2 and Cxcl10) expression. By contrast, miR-155 antagonist upregulated SOCS1 and had a protective effect on renal cells by decreasing STAT1/3 phosphorylation and pro-inflammatory gene expression. Additionally, loss- or gain-of function experiments indicate a direct implication of SOCS1 in the regulation of miR-155 expression by STAT transcription factors. Conclusion Our study indicates a pro-inflammatory role of miR-155 in diabetic kidney disease by downregulating renal expression of SOCS1. Therefore, antagonism of miR-155 may have a renoprotective effect in diabetic nephropathy through SOCS1-mediated feedback inhibition of JAK/STAT overactivation. Ongoing in vivo studies with miR-155 inhibitor in experimental diabetes will clarify its role in the development and progression of diabetic nephropathy.

Sarcopenia and serum biomarkers of oxidative stress after a 6-month physical activity intervention in women with metastatic breast cancer: results from the ABLE feasibility trial

PurposeSarcopenia has been identified as an important prognostic factor for patients with cancer. This study aimed at exploring the potential associations between a 6-month physical activity intervention and muscle characteristics, sarcopenia, oxidative stress and toxicities in patients with metastatic breast cancer.MethodsWomen newly diagnosed with metastatic breast cancer (N = 49) participated in an unsupervised, personalized, 6-month physical activity intervention with activity tracker. Computerized tomography images at the third lumbar vertebra were analysed at baseline, three months and six months to assess sarcopenia (muscle mass index < 40 cm2/m2) and muscle quality (poor if muscle attenuation < 37.8 Hounsfield Units). Oxidative markers included plasma antioxidant enzymes (catalase, glutathione peroxidase and superoxide dismutase activities), prooxidant enzymes (NADPH oxidase and myeloperoxidase activities) and oxidative stress damage markers (advanced oxidation protein products, malondialdehyde (MDA) and DNA oxidation.ResultsAt baseline 53% (mean age 55 years (SD 10.41)) were sarcopenic and 75% had poor muscle quality. Muscle cross sectional area, skeletal muscle radiodensity, lean body mass remained constant over the six months (p = 0.75, p = 0.07 and p = 0.75 respectively), but differed significantly between sarcopenic and non-sarcopenic patients at baseline and 6-months. Sarcopenic patients at baseline were more likely to have an increase of MDA (p = 0.02) at 6 months. Being sarcopenic during at least one moment during the 6-month study was associated with a higher risk of developing severe toxicities (grade > 2) (p = 0.02).ConclusionsThis study suggests potential benefits of physical activity for maintenance of muscle mass. Sarcopenia can alter many parameters and disturb the pro and antioxidant balance.