Search

The effects of rutin (6, 30, and 150 μmol/gpro) on the physicochemical, structural properties and gel characteristics of myofibrillar protein (MP) under oxidative stress were investigated. The addition of rutin significantly promoted the formation of oxidized MP carbonyl derivatives and dimer tyrosine, but it cannot prevent the loss of sulfhydryl groups (−SH). With increasing rutin concentration, the hydrophobic area was gradually shielded and rutin acted as a quencher to reduce the fluorescence intensity of oxidized MP. Under the oxidative stress, rutin increased the particle size and aggravated the cleavage of protein molecules. SDS‐polyacrylamide gel electrophoresis revealed that rutin further aggravated oxidized MP degradation and cross‐linked form polymer which cross‐linked with protein to the maximum extent at 150 μmol/gpro rutin content. Moderate cross‐linking between protein and rutin could improve the gel strength and water holding capacity (WHC) of oxidized MP gel. For rutin concentrations of 6 and 30 μmol/gpro, the gels had denser network structures, as observed by scanning electron microscopy. Practical applications: Polyphenols of the type and dosage can change the properties of the product itself and optimize the quality of product processing. Certain polyphenols may promote the oxidation process of protein‐rich products, but this does not affect the improvement of product quality. The application of natural polyphenols is the promising business direction in the development of Coregonus peled industry. [ABSTRACT FROM AUTHOR]

Objective: To investigate the therapeutic effect of carbon monoxide (CO) on high-altitude hypoxia-induced cardiac damage. Methods: Forty male C57BL/6 mice were randomly divided into 4 groups. The mice were exposed to normoxia or simulated 5,500-meter high-altitude hypoxia in a hypobaric chamber for 7 days. During the first 3 days, the mice were pretreated with CO-saturated hemoglobin (Hb)-based oxygen carrier (CO-HBOC), oxygen-saturated hemoglobinbased oxygen carrier (O 2 -HBOC) at a dose of 0.3 g Hb/kg/day or an equivalent volume of saline. The in vivo left ventricle function, cardiac enzyme release, histopathological changes, apoptosis and inflammation were also measured. Results: High-altitude hypoxia induced significant cardiac damage, as demonstrated by impaired cardiac function and increased proapoptotic, proinflammatory and pro-oxidant markers. Pretreatment with CO-HBOC significantly improved cardiac performance, reduced cardiac enzyme release and limited myocardial apoptosis. The increased inflammatory response was also suppressed. In addition to the preserved mitochondrial structure, hypobaric hypoxia-induced mitochondrial oxidative damage was remarkably attenuated. Moreover, these antiapoptotic and antioxidative effects were accompanied by an upregulated phosphorylation of Akt, ERK and STAT3. Conclusion: This study demonstrated that CO-HBOC provides a promising protective effect on high-altitude hypoxia-induced myocardial injury, which is mediated by the inhibition of inflammation and mitochondrial oxidative damage. [ABSTRACT FROM AUTHOR]

The neurotoxin 6-hydroxydopamine (6-OHDA), which causes transcriptional changes associated with oxidative and proteotoxic stress, has been widely used to generate an experimental model of Parkinson’s disease. The food-derived compound luteolin has multi-target actions including antioxidant, anti-inflammatory and neurotrophic activities. The aim of this study is to investigate how luteolin affects 6-OHDA-mediated stress response pathways. The results showed that when PC12 cells were pre-treated with luteolin (20 µM) 30 min prior to 6-OHDA (100 µM) exposure, 6-OHDA-induced ROS overproduction, cytotoxicity, caspase-3 activation, and mRNA expression of BIM, TRB3 and GADD34 were significantly attenuated. Moreover, 6-OHDA-mediated cell cycle arrest and transcription of p53 target genes, p21, GADD45α and PUMA, were reduced by luteolin. Luteolin also significantly down-regulated 6-OHDA-mediated unfolded protein response (UPR), leading to decreases in phospho-eIF2α, ATF4, GRP78 and CHOP. In addition, luteolin attenuated 6-OHDA-induced Nrf2-mediated HO-1 and GCLC. Taken together, these results suggest that diminishing intracellular ROS formation and down-regulation of p53, UPR and Nrf2-ARE pathways may be involved in the neuroprotective effect of luteolin. [ABSTRACT FROM AUTHOR]

Myocardial apoptosis and necroptosis are the major etiological factor during doxorubicin (DOX) induced cardiotoxicity, and one of the important reasons that limit the drug's clinical application. Up to date, its mechanism has not been fully elucidated. The protective role of phosphocreatine (PCr) in heart surgery and medical cardiology has been observed in numerous clinical trials. This study aimed to evaluate cardioprotective actions of PCr against DOX-induced cardiotoxicity and investigate the underlying mechanism involving in transforming growth factor β-activated kinase 1 (TAK1) mediated myocardial survive signaling pathway. Male Sprague-Dawleyrats were intraperitoneally (ip) injected with normal saline (NS) or DOX (2 mg/kg) alone or DOX with PCr (200 mg/kg) used as animal model. The data showed that DOX significantly impaired cardiac function and structure, induced oxidative stress, myocardial apoptosis and necroptosis, and dramatically down-regulated the expression level of TAK1, while the intervention of PCr obviously attenuated cardiac dysfunction, oxidative stress, myocardial apoptosis and necroptosis, especially alleviated the decrease of TAK1 expression. I n vitro analysis, after H9c2 cells were pretreated with or without PCr (0.5 mM) or N-Acetyl-L-cysteine (NAC, 0.5 mM) or 5Z-7-oxozeaenol (5z-7-Ox, 1 μM) for 1 h, subsequently treated with DOX (1 μM) for 24 h. The results revealed that inhibition of TAK1 further deteriorated apoptotic and necroptotic cell death induced by DOX in H9c2 cells, but didn't affect oxidative stress. While the pretreatment of PCr or NAC enhanced antioxidant activity to reduce oxidative stress, significantly alleviated apoptotic and necroptotic cell death induced by DOX in H9c2 cells. Consistent with the results in vivo , PCr or NAC significantly inhibited the decrease of TAK1 expression induced by DOX. In conclusion, oxidative stress induced by DOX inhibits the expression of TAK1, and leads to myocardial apoptotic and necroptotic death, while the intervention of PCr increases antioxidant activity to alleviate oxidative stress, which in turn activates TAK1 signaling pathway to promote myocardial survival, and finally attenuate DOX-induced cardiotoxicity. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) is problem that has become one of the major issues affecting public health. Extensive clinical data suggests that the prevalence of hyperlipidemia in CKD patients is significantly higher than in the general population. Lipid metabolism disorders can damage the renal parenchyma and promote the occurrence of cardiovascular disease (CVD). Cyanate is a uremic toxin that has attracted widespread attention in recent years. Usually, 0.8% of the molar concentration of urea is converted into cyanate, while myeloperoxidase (MPO) catalyzes the oxidation of thiocyanate to produce cyanate at the site of inflammation during smoking, inflammation, or exposure to environmental pollution. One of the important physiological functions of cyanate is protein carbonylation, a non-enzymatic post-translational protein modification. Carbamylation reactions on proteins are capable of irreversibly changing protein structure and function, resulting in pathologic molecular and cellular responses. In addition, recent studies have shown that cyanate can directly damage vascular tissue by producing large amounts of reactive oxygen species (ROS). Oxidative stress leads to the disorder of liver lipid metabolism, which is also an important mechanism leading to cirrhosis and liver fibrosis. However, the influence of cyanate on liver has remained unclear. In this research, we explored the effects of cyanate on the oxidative stress injury and abnormal lipid metabolism in mice and HL-7702 cells. In results, cyanate induced hyperlipidemia and oxidative stress by influencing the content of total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), superoxide dismutase (SOD), catalase (CAT) in liver. Cyanate inhibited NF-E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and the phosphorylation of adenosine 5′monophosphate-activated protein kinase (AMPK), activated the mTOR pathway. Oxidative stress on the cells reduced significantly by treating with TBHQ, an antioxidant, which is also an activator of Nrf2. The activity of Nrf2 was rehabilitated and phosphorylation of mTOR decreased. In conclusion, cyanate could induce oxidative stress damage and lipid deposition by inhibiting Nrf2/HO-1 pathway, which was rescued by inhibitor of Nrf2. [ABSTRACT FROM AUTHOR]

Objectives: High reactive oxygen species (ROS) levels lead to cell death, and the testes are among the most vulnerable organs to oxidative damage. Rg1, an active ingredient extracted from the natural medicine ginseng, has potential anti-inflammatory, antioxidant and antiapoptotic properties. Our previous studies showed that Rg1 can effectively improve spermatogenic function in mice, but the specific mechanism remains unclear. The purpose of this study was to investigate the effect of Rg1 on oxidative stress and spermatogonium apoptosis in D-gal-induced testicular toxicity and elucidate the associated mechanism. Methods: Male C57BL/6 mice at 6–8 weeks of age were intraperitoneally injected with D-gal (200 mg/kg) for 42 days to establish a testicular injury model, and on day 16, 40 mg/kg Rg1-rich saline was injected intraperitoneally. Concurrently, we established an in vitro model of D-gal-damaged spermatogonia, which was treated with Rg1. Results: We found that treatment with the ginsenoside Rg1 reduced D-gal-induced oxidative stress and spermatogonium apoptosis in vivo and in vitro. Mechanistically, we found that Rg1 activated Akt/bad signaling and reduced D-gal-induced spermatogonium apoptosis. Discussion: We provide evidence showing that the antioxidant effect of Rg1 is mediated by the Akt/GSK-3β/NRF2 axis. Based on these findings, we consider Rg1 a potential treatment for testicular oxidative damage. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of miRNAs involving oxidative stress response in doxorubicin (DOX)-induced cardiotoxicity based on the data from Gene Expression Omnibus (GEO) database and experimental results via integrated bioinformatics analysis. MiRNA expression profiles of DOX-induced cardiotoxicity in rat myocardial tissues and adult rat cardiomyocytes (ARC) were extracted from GEO datasets (GSE36239). Differential expression miRNA (DEMs) were separately captured in rat myocardial tissues and in ARC, and intersected between rat myocardial tissues and ARC via Venny 2.1. Subsequently, Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) analyzed 46 target genes of miR-143, one of 6 DEMs, and HIF-1 and PI3K-Akt signaling pathway were significantly enriched. Further experimental results showed DOX-induced oxidative stress downregulated the expression of miR-143, and then promoted target gene Bbc3 expression and H9c2 apoptosis, the intervention of phosphocreatine (PCr) or N -acetyl-L-cystine (NAC) alleviated oxidative stress, apoptosis and Bbc3 expression, upregulated miR-143 in DOX-induced cardiotoxicity in vivo and in vitro. Our findings elucidated the regulatory network between miR-143 and oxidative stress in DOX-induced cardiotoxicity, and might unveiled a potential biomarker and molecular mechanisms, which could be helpful to the diagnosis and treatment of DOX-induced cardiotoxicity. • Analysis of miRNA expression profile of GSE36239 obtained from GEO database. • The expression of miR-143, One of DEMs, was verified in vivo and in vitro. • Enrichment analysis of GO and KEGG signal pathway on target genes of miR-143. • Potential role of miR-143 in PCr improvement of DOX-cardiotoxicity. [ABSTRACT FROM AUTHOR]

B-lymphocytopenia among myelosuppression is the most intractable side effect of chemotherapy. Here, we investigated ways to alleviate 5-fluorouracil-caused stress hematopoietic impairment. We found that intraperitoneally injected ASP (Angelica sinensis polysaccharides) (100 mg/kg per day), one main active ingredient of Angelica sinensis, for consecutive 7 days, significantly recovered mouse bone marrow pro-B and pre-B cells, reversed the capacity of CFU-PreB colony forming, thus alleviating B cell reduction in the spleen and peripheral blood, as well as ameliorating immunoglobin from spleen and serum. The mechanism is related to the protective effects of ASP on IL-7 producing cells, including perivascular Leptin+ and CXCL12+ mesenchymal stem and progenitor cells (MSPCs), thus promoting IL-7 production, and activating IL-7R-mediated STAT5, PI3K-AKT signaling, including survival signals and EBF1, PAX5 transcription factor expression. Additionally, ASP's IL-7 promoting effect was demonstrated to be associated with maintaining osteogenesis/adipogenesis balance of MSPCs via the NRF2 antioxidant pathway. Collectively, our findings indicate that ASP reverse stress B-lymphocytopenia via improving Nrf2 signaling, promoting IL-7 production in MSPCs, and subsequently maintaining survival, proliferation, and differentiation of B cell progenitors, which may represent a promising therapeutic strategy. [Display omitted] • Angelica Sinensis Polysaccharides restore 5-Fluorouracil-induced B-lymphocytopenia. • Angelica Sinensis Polysaccharides antagonize 5-Fluorouracil-caused mesenchymal progenitor oxidative stress via Nrf2 signaling, keeping osteogenic differentiation potential, protecting IL-7 producing cells. • Angelica Sinensis Polysaccharides reverse 5-Fluorouracil-induced decreased IL-7-IL-7R signaling, rescuing the proliferation, survival and differentiation of B cell progenitors. [ABSTRACT FROM AUTHOR]

Angelica Sinensis polysaccharide (ASP), the main active component of Angelica sinensis, possesses antioxidative and anti-apoptotic properties. In this study, we have investigated the antagonistic effect of ASP on 5-FU-induced injury of mouse spleen in vivo and splenocytes in vitro, and its possible mechanism. Our results showed that ASP inhibited 5-FU-induced decreases in spleen weight and organ index in mice, restored the number of peripheral blood leukocytes and lymphocytes, repaired spleen structure disorder and functional impairment, rescued serum IL-2, IL-6, and IFN-γ levels, and relieved 5-FU-induced mitochondrial swelling， reduced the oxidant accumulation including MDA and ROS, whereas increasing the activities of GSH, SOD and CAT. The mechanism may be related to ASP downregulation of Keap1 protein expression thus motivating the nuclear translocation of Nrf2. Furthermore, ASP alleviated the apoptosis of spleens in vivo and splenocytes in vitro, and reactivated PI3K / AKT signalling. In conclusion, the protective effect of ASP on spleens and splenocytes may be related to the reduction of oxidative stress and apoptosis via reactivation of Nrf2 and PI3K/AKT pathways. This study has provided a new protective agent for minimizing the spleen injury caused by 5-FU and a new idea for improving the prognosis of chemotherapy patients. [Display omitted] • ASP restores spleen immune function by alleviating 5-FU-induced apoptosis and oxidative stress. • ASP ameliorates 5-FU-induced oxidative stress through activation of Nrf2. • ASP reactivates PI3K/AKT pathways inhibited by 5-FU to reduce apoptosis. [ABSTRACT FROM AUTHOR]

This present study was designed to investigate the effects of alpha-1-antitrypsin (AAT) on oxidative stress in preeclampsia (PE) by regulating p38 mitogen-activated protein kinase (p38MAPK) signaling pathway. HTR8/SVneo cells were randomly assigned into normal, hypoxia/reoxygenation (H/R), HR + AAT and HR + siRNA-AAT groups. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used to detect the mRNA and protein expressions of p-p38MAPK, AAT, signal transducer and activator of transcription 1 (STAT1) and activating transcription factor2 (ATF2). Flow cytometry, scratch test, cell counting kit-8 (CCK-8) assay and the 3-(4,5)-dimethylthiazol (-z-y1)-3,5-di- phenyltetrazolium bromide (MTT) assay were conducted to detect reactive oxygen species (ROS) and cell apoptosis, cell migration, proliferation and cytotoxicity, respectively. Mouse models in PE were established, which were divided into normal pregnancy (NP), PE and PE + AAT groups with blood pressure and urine protein measured. Chromatin immunoprecipitation (ChIP) and enzyme-linked immunosorbent assay (ELISA) were conducted to detect the activity of oxidative stress-related kinases and expressions of inflammatory cytokines and coagulation-related factors in cells and mice placenta. Immunohistochemistry, Western blotting and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were performed to detect AAT and p38MAPK expressions, apoptosis-related protein expressions, and apoptosis rate in mice placenta. Compared with the normal group, the H/R group had decreased expression of AAT, activity of superoxide dismutase (SOD) and GSH-Px, cell proliferation and migration, but increased p38MAPK, STAT1, ATF2, MDA, H2O2, inflammatory cytokines, coagulation-related factors, cell cytotoxicity, ROS, apoptotic factors and apoptosis rate. Compared with the H/R group, the HR + ATT group had increased expressions of AAT, activity of SOD and GSH-Px, cell proliferation and migration but decreased p38MAPK, STAT1, ATF2, malonyldialdehyde (MDA), H2O2, inflammatory cytokines and coagulation-related factors, cell cytotoxicity, ROS, apoptotic factors and apoptosis rate, while opposite results were observed in the HR + siRNA-ATT group. Compared with the NP group, the PE group had decreased activity of SOD and GSH-Px but increased MDA, H2O2, AAT, p38MAPK, inflammatory cytokines, coagulation-related factors and apoptosis rate. The indexes in the PE + AAT group were between the NP and PE groups. Thus, we concluded that AAT suppressed oxidative stress in PE by inhibiting p38MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

Aim: Glycyrrhizin (GL) has been reported to protect against ischemia and reperfusion (I/R)-induced injury by inhibiting the cytokine activity of high mobility group box 1 (HMGB1). In the present study, the protective effects of GL against I/R injury, as well as the related molecular mechanisms, were investigated in rat brains. Methods: Focal cerebral I/R injury was induced by intraluminal filamentous occlusion of the middle cerebral artery (MCA) in Male Sprague-Dawley rats. GL alone or GL and rHMGB1 were administered intravenously at the time of reperfusion. Serum levels of HMGB1 and inflammatory mediators were quantified via enzyme-linked immunosorbent assay (ELISA). Histopathological examination, immunofluorescence, RT-PCR and western blotting analyses were performed to investigate the protective and anti-apoptotic effects and related molecular mechanisms of GL against I/R injury in rat brains. Results: Pre-treatment with GL significantly reduced infarct volume and improved the accompanying neurological deficits in locomotor function. The release of HMGB1 from the cerebral cortex into the serum was inhibited by GL administration. Moreover, pre-treatment with GL alleviated apoptotic injury resulting from cerebral I/R through the inhibition of cytochrome C release and caspase 3 activity. The expression levels of inflammation- and oxidative stress-related molecules including TNF-α, iNOS, IL-1β, and IL-6, which were over-expressed in I/R, were decreased by GL. P38 and P-JNK signalling were involved in this process. All of the protective effects of GL could be reversed by rHMGB1 administration. Conclusions: GL has a protective effect on ischemia-reperfusion injury in rat brains through the inhibition of inflammation, oxidative stress and apoptotic injury by antagonising the cytokine activity of HMGB1. [ABSTRACT FROM AUTHOR]