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ObjectiveTo observe the effect of earthworm protein on the expression of phosphatidylinositol 3-kinase/protein kinase B/nuclear factor E2-related factor 2 （PI3K/Akt/Nrf2） pathway in the aorta of spontaneously hypertensive rats （SHR） and explore mechanism of earthworm protein in treating hypertensive vascular endothelial dysfunction （VED）. MethodTen 10-week-old Wistar Kyoto （WKY） rats and fifty SHR rats were selected for a week of adaptive feeding. WKY rats were selected as the normal group， and fifty SHR rats were randomized according to body weight into model， valsartan （8×10-3 g·kg-1·d-1）， and high-， medium-， and low-dose （0.2， 0.1， 0.05 g·kg-1·d-1， respectively） earthworm protein groups. The normal and model groups were administrated with equal volume of double distilled water by gavage. During the drug intervention period， the general situations of rats in each group were observed and their blood pressure was monitored at specific time points every other week before and after administration. After 8 weeks of drug intervention， enzyme-linked immunosorbent assay was employed to measure the levels of angiotensin-Ⅱ （Ang-Ⅱ） and endothelin-1 （ET-1） in the serum of rats in each group. The corresponding kits were used to determine the levels of nitric oxide （NO）， malondialdehyde （MDA）， glutathione peroxidase （GPX）， superoxide dismutase （SOD）， and ferrous ion （Fe2+）. Hematoxylin-eosin （HE） staining was employed to observe the changes in the intima of the aorta. Fluorescence quantitative polymerase chain reaction （Real-time PCR） was employed to measure the mRNA levels of PI3K， Akt， Nrf2， heme oxygenase-1 （HO-1）， and glutathione peroxidase 4 （GPX4） in the aortic tissue. Western blotting was used to determine the protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 in the thoracic aorta. ResultCompared with the normal group， the model group had decreased body mass， increased irritability， severe endothelial damage， elevated blood pressure and serum levels of Ang-Ⅱ， ET1， MDA， and Fe2+ （P<0.01）， lowered NO level （P<0.01）， and down-regulated mRNA and protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 in the aortic tissue （P<0.01）. Compared with the model group， drug intervention caused no significant change in the body mass， calmed the rats， alleviated the endothelial damage， lowered blood pressure and serum levels of Ang-Ⅱ， ET1， MDA， and Fe2+ （P<0.01）， elevated the NO level （P<0.05）， and up-regulated the mRNA and protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 （P<0.05）. ConclusionThe earthworm protein can exert antihypertensive effects by ameliorating VED in SHR. Specifically， it may regulate the PI3K/Akt/Nrf2 signaling pathway to inhibit oxidative stress and ferroptosis.
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ObjectiveTo investigate the effects of Xinjia Congrong Tusizi decoction （XJCTD） on ovarian functions in the rat model of premature ovarian insufficiency （POI） and decipher the mechanism of regulating the tumor suppressor protein （p53）/nuclear factor E2-related factor 2 （Nrf2） pathway to attenuate granulosa cell ferroptosis. MethodForty-eight SPF-grade female SD rats were randomized into control， model， low-， medium-， and high-dose （1.1， 2.2， 4.4 g·kg-1） XJCTD， and Western medicine （coenzyme Q10， 0.002 7 g·kg-1） groups， with eight rats in each group. The rat model of POI was established by gavage of triptolide （TP）， and after successful modeling， each group was administrated with the corresponding drugs by gavage for 14 d. The body weight and ovarian weight of each rat were weighed and the ovarian index was calculated. The morphology of the ovarian tissue was observed by hematoxylin-eosin staining， and the proportions of growing follicles and atretic follicles were calculated. The serum levels of anti-Müllerian hormone （AMM）， estradiol （E2）， and follicle-stimulating hormone （FSH） were measured by enzyme-linked immunosorbent assay （ELISA）. The DCFH-DA fluorescent probe was used to measure the reactive oxygen species （ROS） content in granulosa cells. The content of cellular Ferrous ion （Fe2+）， lipid peroxide （LPO）， malondialdehyde （MDA）， glutathione （GSH）， and superoxide dismutase （SOD） was detected by colorimetry. The expression of the tumor suppressor protein p53，Nrf2， solute carrier family 7 member 11 （SLC7A11）， and glutathione peroxidase 4 （GPX4） was determined by immunohistochemistry and Western blot. ResultCompared with the control group， the model group showed decreased ovarian weight， body weight， and ovarian index （P<0.01）， reduced ovarian tissue volume and proportion of growing follicles （P<0.01）， increased proportion of atretic follicles （P<0.01）， lowered AMH and E2 levels and elevated FSH level in the serum （P<0.01）， and elevated levels of Fe2+， ROS， LPO， and MDA （P<0.01） and lowered levels of GSH and SOD in granulosa cells （P<0.01）. Moreover， the modeling up-regulated the expression of p53 （P<0.01） and down-regulated the expression of Nrf2， SLC7A11， and GPX4 （P<0.05， P<0.01） in the ovarian tissue. Compared with the model group， XJCTD increased the body weight， ovarian weight， and ovarian index （P<0.01）， alleviated the pathological changes in the ovarian tissue， increased the proportion of growing follicles （P<0.01）， decreased the proportion of atretic follicles （P<0.01）， and reduced the content of ROS in granulosa cells （P<0.05， P<0.01）. In addition， medium- and high-dose XJCTD lowered the FSH level （P<0.01） and raised E2 and AMH levels （P<0.01） in the serum， reduced the Fe2+ content （P<0.05， P<0.01）， and increased the SOD content （P<0.01） in granulosa cells. High-dose XJCTD reduced the LPO and MDA content （P<0.01） and increased the SOD content （P<0.01） in the granulosa cells， down-regulated the expression of p53 （P<0.05）， and up-regulated the expression of Nrf2， SLC7A11， and GPX4 in the ovarian tissue （P<0.05， P<0.01）. ConclusionXJCTD may protect the ovarian function in the rat model of POI by regulating the p53/Nrf2 signaling pathway to attenuate the ferroptosis of ovarian granulosa cells.
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Objective:To investigate the regulatory effect of astaxanthin on oxidative stress injury induced by hydrogen peroxide (H 2O 2) in lens epithelial cells and its possible mechanism. Methods:The HLEB-3 cells were cultured with different concentrations (0, 50, 100, 200, 500, 750 μmol/L) of H 2O 2.The cell inhibition rate was detected by the methyl thiazolyl tetrazolium (MTT) method, and the 50%inhibiting concentration (IC50) was calculated.HLEB-3 cells were cultured with different concentrations (0, 5, 10, 20, 50 μmol/L) of astaxanthin.The cell survival rate was detected by the MTT method.HLEB-3 cells were divided into four groups for 24-hour culture, namely normal control group cultured with complete medium, oxidative stress group cultured with 250 μmol/L H 2O 2, 10 μmol/L astaxanthin group cultured with 10 μmol/L astaxanthin and 250 μmol/L H 2O 2, and 20 μmol/L astaxanthin group cultured with 20 μmol/L astaxanthin and 250 μmol/L H 2O 2.The cell apoptosis rate was determined by flow cytometry.The nitric oxide (NO) concentration, superoxide dismutase (SOD) activity, glutathione (GSH) activity and malondialdehyde (MDA) content were detected by ELISA.The protein expressions of nuclear factor erythroid-2 related factor 2 (Nrf2) in nuclei, cytoplasmic Nrf2, heme oxygenase-1 (HO-1) and NAD (P) H, quinine oxidoreductase 1 (NQO1) were detected by Western bolt.The cells were divided into four groups, namely normal control-small interfering RNA (NC-siRNA) group, Nrf2-siRNA group, NC-siRNA+ astaxanthin group and Nrf2-siRNA+ astaxanthin group.The cells were transfected with NC-siRNA or Nrf2-siRNA accordingly.The cells were co-cultured for 24 hours with 0/10 μmol/L astaxanthin and 250 μmol/L H 2O 2 24 hours after transfection, respectively.The cell apoptosis rate was determined by flow cytometry.The NO concentration, SOD activity, GSH activity and MDA content were detected by ELISA. Results:With the increase of H 2O 2 concentration, the inhibition rate of HLEB-3 cells increased.There were significant differences in the inhibition rate of HLEB-3 cells treated with different concentrations of H 2O 2 ( F=12.358, P<0.05). The IC50 value of H 2O 2 on HLEB-3 cells was 264.20 μmol/L.The survival rates of HLEB-3 cells treated with 0, 5, 10, 20 and 50 μmol/L astaxanthin were (100.00±0.00)%, (102.20±1.34)%, (109.50±3.60)%, (115.40±4.13)%, (93.60±2.59)%, respectively.Then 10 μmol/L and 20 μmol/L were chosen as the experimental dose.The cell apoptosis rate of oxidative stress group was (38.50±2.38)%, which was higher than (9.20±0.24)% of normal control group, with a statistically significant difference ( P<0.05). The cell apoptosis rate of 10 μmol/L astaxanthin group was (27.60±4.33)%, which was lower than (38.50±2.38)% of oxidative stress group, but higher than (14.90±1.23)% of 20 μmol/L astaxanthin group and (9.20±0.24)% of normal control group, showing statistically significant differences (all at P<0.05). The NO and MDA contents were higher and the SOD and GSH concentrations were lower in oxidative stress group than in normal control group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group, and the differences were statistically significant (all at P<0.05). The NO and MDA contents were higher and the SOD and GSH concentrations were lower in 10 μmol/L astaxanthin group than in normal control group and 20 μmol/L astaxanthin groups, and the differences were statistically significant (all at P<0.05). There were significant differences in the relative expression levels of nuclear Nrf2, cytoplasmic Nrf2, HO-1 and NQO1 proteins among normal control group, oxidative stress group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group ( F=43.512, 20.381, 31.014, 23.435; all at P<0.001). The relative expression of nuclear Nrf2 protein gradually decreased, and the relative expression of nuclear Nrf2, HO-1 and NQO1 proteins increased gradually in normal control group, oxidative stress group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group, and there were significant differences when compared in pairs (all at P<0.05). The apoptosis rates of Nrf2-siRNA group and Nrf2-siRNA+ astaxanthin group were higher than those of NC-siRNA group and NC-siRNA+ astaxanthin group, and the differences were statistically significant (all at P<0.05). The cell apoptosis rate was higher in NC-siRNA group than in NC-siRNA+ astaxanthin group, showing a statistically significant difference ( P<0.05). There was no significant difference in the apoptosis rate between Nrf2-siRNA+ astaxanthin group and Nrf2-siRNA group ( P>0.05). The NO and MDA concentrations were higher and the SOD and GSH activities were lower in Nrf2-siRNA group than in the NC-siRNA group, with statistically significant differences (all at P<0.05). The NO and MDA concentrations were lower and the SOD and GSH activities were higher in NC-siRNA+ astaxanthin group than in NC-siRNA group and Nrf2-siRNA+ astaxanthin group, and the differences were statistically significant (all at P<0.05). There was no significant difference in NO and MDA concentrations or the SOD and GSH activities between Nrf2-siRNA+ astaxanthin group and Nrf2-siRNA group (all at P>0.05). Conclusions:Astaxanthin enhances the resistance of lens epithelial cells to H 2O 2-induced oxidative stress damage, which may be achieved by activating the Nrf2-related signaling pathway.
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Oxidative stress(OS)is a major reason for body damage. Studies have shown that a variety of factors, such as ischemia and hypoxia, excessive light and hyperglycemia can cause the increase of reactive oxygen species and free radicals in the retina, thus inducing OS, damaging retina and affecting the normal visual function. Kelch-like ECH-associated protein 1(KEAP1)and nuclear factor erythroid 2 related factor 2(NRF2), which together constitute the main antioxidant stress signaling pathway in the body, play an antioxidant role by regulating retinal energy metabolism and cell proliferation, apoptosis and autophagy through various ways, so as to reduce retinal damage caused by OS. In this paper, the role and mechanism of the KEAP1-NRF2 signaling pathway regulation of OS in the retinal are briefly reviewed, aiming to provide ideas for subsequent research.
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OBJECTIVE@#To explore the mechanism underlying the inhibitory effect of quercetin against testicular oxidative damage induced by a mixture of 3 commonly used phthalates (MPEs) in rats.@*METHODS@#Forty male Sprague-Dawley rats were randomly divided into control group, MPEs exposure group, and MPEs with low-, median- and high-dose quercetin treatment groups. For MPEs exposure, the rats were subjected to intragastric administration of MPEs at the daily dose of 900 mg/kg for 30 consecutive days; Quercetin treatments were administered in the same manner at the daily dose of 10, 30, and 90 mg/kg. After the treatments, serum levels of testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and testicular malondialdeyhde (MDA), catalase (CAT) and superoxide dismutase (SOD) were detected, and testicular pathologies of the rats were observed with HE staining. The expressions of nuclear factor-E2-related factor 2 (Nrf2), Kelch-like ECH2 associated protein 1 (Keap1) and heme oxygenase 1 (HO-1) in the testis were detected using immunofluorescence assay and Western blotting.@*RESULTS@#Compared with the control group, the rats with MPEs exposure showed significant reductions of the anogenital distance, weight of the testis and epididymis, and the coefficients of the testis and epididymis with lowered serum testosterone, LH and FSH levels (P < 0.05). Testicular histological examination revealed atrophy of the seminiferous tubules, spermatogenic arrest, and hyperplasia of the Leydig cells in MPEs-exposed rats. MPEs exposure also caused significant increments of testicular Nrf2, MDA, SOD, CAT and HO-1 expressions and lowered testicular Keap1 expression (P < 0.05). Treatment with quercetin at the median and high doses significantly ameliorated the pathological changes induced by MPEs exposure (P < 0.05).@*CONCLUSION@#Quercetin treatment inhibits MPEs-induced oxidative testicular damage in rats possibly by direct scavenging of free radicals to lower testicular oxidative stress and restore the regulation of the Nrf2 signaling pathway.
Subject(s)
Rats , Male , Animals , Testis , Quercetin/pharmacology , Rats, Sprague-Dawley , NF-E2-Related Factor 2/metabolism , Kelch-Like ECH-Associated Protein 1/metabolism , Oxidative Stress , Testosterone/pharmacology , Superoxide Dismutase/metabolism , Follicle Stimulating Hormone , Luteinizing HormoneABSTRACT
Aim To investigate the protective effect of essential oil from Fructus Alpiniae Zerumbet (EOFAZ ) on type 2 diabetes-induced pancreatic injury in mice and its mechanism.Methods After C57 BL/6 mice fed with high-sugar and high-fat ( HFS) feed developed insulin resistance, streptozotocin ( STZ, 120 mg • kg 1 ) was injected intraperitoneal
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ObjectiveTo explore the underlying mechanism of Gegen Qinliantang （GGQL） in the treatment of ulcerative colitis （UC） in rats and discuss the effects of modification of GGQL on its efficacy. MethodThe UC model was induced in rats by free access to 5% dextran sulfate sodium in saline solution. Male SD rats were randomly divided into a normal group， a model group， a positive control group （sulfasalazine enteric-coated tablets， 350 mg·kg-1）， a GGQL group （17 g·kg-1）， a Glycyrrhizae Radix et Rhizoma （GR）-absent GGQL group （17 g·kg-1）， a Puerariae Lobatae Radix （PLR）-absent GGQL group （17 g·kg-1）， a GR-PLR group （17 g·kg-1）， and a Scutellariae Radix （SR）-Coptidis Rhizoma （CR） group （17 g·kg-1）. The in vitro antioxidant activities of GGQL and its combinations were evaluated by 2，2-diphenyl-1-picrylhydrazyl （DPPH）， 2，2′-azino-bis（3-ethylbenzothiazoline-6-sulfonic acid） （ABTS）， and fluorescence recovery after photobleaching （FRAP） methods. The degree of colonic tissue injury in each group was evaluated based on the weight changes of rats， the length of the colon， the colon sections， and hematoxylin-eosin （HE）-stained histopathologic sections. The serum levels of myeloperoxidase （MPO）， lipid peroxide （LPO）， malondialdehyde （MDA）， total superoxide dismutase （T-SOD）， catalase （CAT）， and reduced glutathione （GSH） were measured by colorimetry. The mRNA and protein expression of nuclear factor-erythroid 2 related factor （Nrf2）， quinone oxidoreductase 1 （NQO1）， and heme oxygenase-1 （HO-1） in colon tissues was detected by real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） and Western blot， respectively. ResultCompared with the normal group， the model group showed colonic mucosal necrosis， inflammatory infiltration， increased serum levels of MPO， LPO， and MDA （P<0.01）， blunted activities of T-SOD， CAT， and GSH （P<0.01）， decreasing trend of mRNA expression of Nrf2， NQO1， and HO-1， reduced expression of Nrf2 protein （P<0.01）， and decreasing trend of expression of NQO1 and HO-1 proteins. Compared with the model group， the GGQL and its combination groups showed improved pathological injury and morphological structure of colon tissues in UC rats， reduced serum levels of MPO， LPO， and MDA （P<0.05）， potentiated T-SOD activity （the PLR-absent GGQL group）， CAT activity （the GR-absent GGQL group and the SR-CR group）， and GSH activity （P<0.01）， and increased mRNA and protein expression of Nrf2， NQO1， and HO-1 in colon tissues. The difference in the GGQL group was significant （P<0.05）. ConclusionGGQL has a restorative effect on the pathological injury of UC rats， and its mechanism may be related to the activation of the Nrf2 signaling pathway and inhibition of oxidative stress response. The absence of PLR or only presence of SR and CR has a great impact on the treatment of UC. The results can provide references for the clinical rational medication of Chinese medicine and the research on the mechanism of compound combinations.
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Objective: To explore the impact of fucoxanthin on oxidized low-density lipoprotein (OxLDL)-induced stress and inflammation in human endothelial cells and its underlying mechanisms. Methods: HUVECs were treated with OxLDL and/or fucoxanthin for a range of time points and concentrations. We evaluated the effects of fucoxanthin on OxLDL-induced HUVECs using the MTT assay, reactive oxygen species accumulation assay, ELISA, RT-PCR, immunofluorescence, and Western blotting. Results: Fucoxanthin enhanced the cell viability in a dose dependent manner after OxLDL exposure. Furthermore, fucoxanthin pretreatment significantly decreased OxLDL-induced reactive oxygen species production and prevented the activation of the nuclear factor kappa-B pathway, which led to substantial suppression of pro-inflammatory gene expressions. OxLDL-induced upregulation of interleukin-6, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, interleukin-1β, monocyte chemotactic protein-1, cyclooxygenase-1, and tumor necrosis factor-α was significantly reduced by fucoxanthin. Conclusions: Fucoxanthin can inhibit OxLDL-induced vascular inflammation and oxidative stress in HUVECs by targeting Nrf2 signaling pathways.
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Aim To study the protective effect of proanthocyanidins extracted from Rubus amabilis Focke (RPC) on the pancreatic tissues of diabetic mice and the underlying mechanism. Methods C57BL/6 male mice were given a high-sugar and high-fat diet combined with an intraperitoneal injection of STZ to establish the diabetic model. The mice whose FBG were higher than 16. 7 mmol · L
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Objective To study the effect of atmospheric particulate exposure on the expression of key molecules of Nrf2 signaling pathway involved in oxidative stress and inflammatory response factors in myocardium of rats fed with high-fat and high-glucose diet. Methods A total of 48 SD male rats were randomly divided into control group (CC group), high-fat and high-glucose diet group (HC group), atmospheric particulates group (CP group) and atmospheric particulates plus high-fat and high-glucose diet group (HP group), with 12 rats in each group.Rats were fed in individual ventilated cages (IVC).The CC and HC groups were placed in IVCs equipped with the atmospheric particulate filter, however, the CP and HP groups without the atmospheric particulate filter to make the air composition similar to the outdoor.A total of 24 rats were sacrificed for acquiring myocardial tissue after 3 and 6 months of exposure.The mRNA expression of Nrf2, HO-1, NQO1, VCAM-1 and MCP-1 were measured using RT-qPCR and the protein expression of VCAM-1, MCP-1 detected using western blot. Results The mRNA expression levels of Nrf2, HO-1, NQO1, VCAM-1 and MCP-1 and the protein expression levels of VCAM-1 and MCP-1 in HC, CP and HP groups were higher than CC group (P < 0.05).The mRNA expression levels of Nrf2, HO-1, NQO1, VCAM-1, MCP-1 and the protein expression levels of VCAM-1, MCP-1 in the HP group were higher than HC and CP groups (P < 0.05).The mRNA expression levels of Nrf2 in CP and HP groups after 6 months of exposure were lower than that at 3 months (P < 0.05). Conclusion The exposure of atmospheric particles, high-fat and high-glucose and their combination diets could cause myocardial tissue inflammatory responses, and activate Nrf2 signaling pathways to protect against myocardial damage.
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AIM:To investigate the effects of ginsenoside RH 2(GS-RH2 )on neovascularization of rats with middle cerebral artery occlusion(MCAO)and its potential mechanisms.METHODS:SPF Sprague-Dawley rats were ran-domly divided into sham operation(sham)group,MCAO model(MCAO)group and GS-RH2 group,with 18 rats in each group.After surgery,the general condition and neurological function score of the rats were assessed.At the 1st day,3rd day and 7th day after intervention,the microvessel density(MVD),the content of malondialdehyde(MDA)and the activ-ity of superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)were examined.The protein expression of kelch-like ECH-associated protein 1(Keap1),nuclear factor E2-related factor 2(Nrf2)and heme oxygenase-1(HO-1)was de-termined by Western blot.RESULTS:Compared with sham group ,the rats in MCAO group showed significant neurobe-havioral obstacles and ischemic brain infarction with higher neurological function score ,while treatment with GS-RH2 sig-nificantly improved behavioral impairment and reduced the infarction volume with lower neurological function score.The MVD score in GS-RH2 group was increased as the animal survival time prolonged ,while the MVD score in MCAO group was decreased.After intervention for 7 d,the MVD score in GS-RH2 group was significantly higher than that in MCAO group(P<0.05).Compared with sham group,the content of MDA was increased and the activities of SOD and GSH-Px were decreased in MCAO group at each time point.After intervention for 7 d,the MDA content was decreased and the SOD and GSH-Px activities were increased in GS-RH2 group compared with MCAO group.After intervention for 7 d,the protein expression of Nrf2 and HO-1 was increased,while the protein expression of Keap1 was decreased in GS-RH2 group com-pared with MCAO group(P<0.05).CONCLUSION:Ginsenoside RH2 promotes neovascularization of MCAO model rats.The mechanism may be related to the activation of Keap 1/Nrf2 signaling pathway ,promotion of the antioxidant enzyme activity and inhibition of oxidative stress.
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AIM:To investigate the role of hydrogen molecule on apoptosis-related proteins in glomerular me-sangial cells cultured with high glucose and to explore its possible mechanism.METHODS:Mouse glomerular mesangial cells cultured in vitro were divided into 4 groups:normal control group(C group,5.5 mmol/L glucose),mannitol group(G group,5.5 mmol/L glucose+19.5 mmol/L mannitol),high glucose group(H group,25 mmol/L glucose),high glu-cose+hydrogen-rich water group(HH group,25 mmol/L glucose+hydrogen-rich water),and cultured for 48 h.The pro-tein levels of Bax,Bcl-2,cleaved caspase-3,nuclear factor E2-related factor-2(Nrf2),heme oxygenase-1(HO-1)and NAD(P)H:quinone oxidoreductase-1(NQO-1)were determined by Western blot ,and the mRNA expression of HO-1 and NQO-1 was determined by RT-PCR.The level of intracellular reactive oxygen species(ROS)was detected by dihydro-ethidium method,and the activity of superoxide dismutase(SOD)was measured by WST-8 assay.RESULTS:Compared with C group,the protein levels of Bax and cleaved caspase-3 were up-regulated,and Bcl-2 was down-regulated in H group(P <0.05).No significantly difference of the protein levels mentioned above between C and HH group was observed. Compared with H group,the protein levels of Bax and cleaved caspase-3 were down-regulated,and Bcl-2 was up-regulated in HH group(P <0.05).The level of intracellular ROS was higher and the activity of SOD was lower in H group than those in C group(P<0.05).However,there was no difference of the SOD activity between C group and HH group.The level of intracellular ROS decreased and the activity of SOD increased in HH group as compared with H group(P<0.05). Compared with C group,clearly reduced protein expression of Nrf2,HO-1 and NQO-1,and decreased mRNA expression of HO-1 and NQO-1 in H group were observed(P<0.05).Compared with H group,the protein levels of Nrf2,HO-1 and NQO-1 as well as the mRNA levels of HO-1 and NQO-1 were obviously increased in HH group(P<0.05 ).CONCLU-SION:Hydrogen molecule inhibits the expression of pro-apoptotic proteins and induces the expression of anti-apoptotic pro-teins in glomerular mesangial cells cultured with high glucose.The mechanism may be related to activation of Nrf 2 signaling pathway.
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Objective To discuss the effect of the electric stimulation on the free radicals and Nrf2 signaling pathway in skeletal muscle myoblasts(C2C12) of mice.Methods After 6 days of differentiation,skeletal muscle myoblasts(C2C12) cells of mice were randomly divided into a control group and an electrical stimulation group.The control group was not stimulated,while the electrical group was stimulated 30,45,60,75,90,120 and 150 minutes respectively with the electrical parameter as 20 ms,45 V and 5 Hz.The reactive oxygen species(ROS),glutathione peroxidase(GSH-Px) and nuclear factor E2 related factor 2(Nrf2) protein expression in C2C12 muscle tubes were determined.Results Compared with the control group,the amount of ROS produced in the C2C12 muscle tube increased significantly in the stimulation group(P＜0.05),except those stimulated for 30 and 150 minutes,with greatest increase for those stimulated for 60 and 120 minutes(P＜0.01).Compared with the control group,the activity of GSH-Px and the expression of Nrf2 nuclear protein increased significantly in all the stimula tion group(P＜0.05),except those stimulated for 30 minutes and with the greatest increase for those stimulated for 75 and 150 minutes(P＜0.01).Conclusion The electrical stimulation of 45 V,20 ms and 5 Hz can cause oxidative stress in the C2C12 muscle tube.Based on the variation of ROS production with the time of electric stimulation,it is found that only when ROS increases to a certain amount,can it activate the Nrf2 signaling system and related genes to make the GSH-Px play an antioxidant role.However,with the increase of stimulation time,the anti-oxidative ability decreases slightly,and then it continues to maintain its high level.
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The present study was designed to evaluate the cardioprotective effect of latifolin on pituitrin(Pit) or isoproterenol(ISO)-induced myocardial injury in rats, and further investigate its underlying mechanisms. Rats were administrated sublingually with pituitrin or subcutaneously with isoproterenol to induce acute myocardial ischemia in rats, and lead II electrocardiograph was recorded. In rats with isoproterenol, ELISA assay or colorimetric method was used to detect the content or activity of myocardial injury markers in serum, and the SOD activity and MDA content in myocardium were detected by colorimetric assay; histopathological examination was conducted by HE staining; the frozen section of myocardial tissues was used for DCFH-DA fluorescent staining to detect the content of ROS in myocardium; Western blot was used to detect the protein expression levels of Nrf2, Keap1, HO-1 and NQO1 in myocardium. Results showed that latifolin significantly inhibited ST-segment changes induced by pituitrin or isoproterenol, and increased heart rate. Further mechanism study showed that latifolin reduced cardiac troponin I(cTnI) level, aspartate transaminase(AST) and lactate dehydrogenase(LDH) activities in serum, increased myocardial superoxide dismutase(SOD) activity and reduced myocardial malondialdehyde(MDA) level, and protected myocardium with less necrosis, infiltration of inflammatory cells and fracture of myocardial fibers. Furthermore, latifolin obviously reduced ROS level in myocardium, inhibited the expression of Kelch-like ECH-associated protein-1(Keap1), increased the nuclear translocation of nuclear factor erythroid 2 related factor 2(Nrf2), and promoted the expression of Heme oxygenase-1(HO-1) and NAD(P)H quinone oxidoreductase-1 (NQO1) in myocardial tissues. Our data suggest that latifolin has a potent protective effect against pituitrin or isoproterenol-induced myocardial injury, which may be related to inhibition of oxidative stress by activating Nrf2 signaling pathway.
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Ligusticum chuanxiong is one of the common traditional Chinese medicinal herbs for treating various cardiovascular and cerebrovascular diseases, and a number of previous studies have demonstrated that the extract of L. chuanxiong has strong antioxidative activity. This paper was mainly aimed to investigate the effects and possible mechanisms of L. chuanxiong extraction on oxidative stress induced by myocardial ischemia injury in rats. The rats were subcutaneously injected with isoprenaline hydrochloride to induce myocardial ischemia injury and treated for 2 weeks. Then the cardiac indexes of the rats were recorded. The concentration of malondialdehyde (MDA) and activities of serum creatine kinase (CK), lactate dehydrogenase (LDH), aspartate transaminase (AST), superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) were measured by colorimetry. Light microscope was used to observe the morphological changes of myocardium, and the protein expressions of nuclear factor E2 related factor 2 (Nrf2), quinone oxidoreductase (NQO1) and hemeoxygenase-1 (HO-1) in cardiac tissue were evaluated by Western blot. The results showed that L. chuanxiong extraction could decrease cardiac indexes and the values of CK, LDH and AST in blood serum, increase activities of serum SOD and T-AOC, reduce serum MDA concentration, improve myocardium structure after ischemia injury, and up-regulate the protein expressions of Nrf2, NQO1 and HO-1 in cardiac tissue. These findings revealed that the cardioprotective effects of L. chuanxiong extraction may be related to inhibiting oxidative stress through the activation of Nrf2 signaling pathway.
ABSTRACT
Oxidative stress activates several intracellular signaling cascades that may have deleterious effects on neuronal cell survival. Thus, controlling oxidative stress has been suggested as an important strategy for prevention and/or treatment of neurodegenerative diseases. In this study, we found that ginsenoside Rh1 inhibited hydrogen peroxide-induced reactive oxygen species generation and subsequent cell death in rat primary astrocytes. Rh1 increased the expression of phase II antioxidant enzymes, such as heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1, superoxide dismutase-2, and catalase, that are under the control of Nrf2/ARE signaling pathways. Further mechanistic studies showed that Rh1 increased the nuclear translocation and DNA binding of Nrf2 and c-Jun to the antioxidant response element (ARE), and increased the ARE-mediated transcription activities in rat primary astrocytes. Analysis of signaling pathways revealed that MAP kinases are important in HO-1 expression, and act by modulating ARE-mediated transcriptional activity. Therefore, the upregulation of antioxidant enzymes by Rh1 may provide preventive therapeutic potential for various neurodegenerative diseases that are associated with oxidative stress.
Subject(s)
Animals , Rats , Antioxidant Response Elements , Astrocytes , Catalase , Cell Death , Cell Survival , DNA , Gene Expression , Heme Oxygenase-1 , Hydrogen , Neurodegenerative Diseases , Neurons , Oxidative Stress , Phosphotransferases , Reactive Oxygen Species , Superoxides , Up-RegulationABSTRACT
<p><b>OBJECTIVE</b>To determine the ability of grape seed proanthocyanidin extract (GSPE) in alleviating arsenic-induced reproductive toxicity.</p><p><b>METHODS</b>Sixty male Kunming mice received the following treatments by gavage: normal saline solution (control); arsenic trioxide (ATO; 4 mg/kg); GSPE (400 mg/kg); ATO+GSPE (100 mg/kg); ATO+GSPE (200 mg/kg) and ATO+GSPE (400 mg/kg). Thereafter, the mice were sacrificed and weighed, and the testis was examined for pathological changes. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), heme oxygenase 1 (HO1), glutathione S-transferase (GST), NAD(P)H dehydrogenase, and quinone 1 (NQO1) expression in the testis was detected by real-time PCR. Superoxide dismutase (SOD), glutathione (GSH), total antioxidative capability (T-AOC), malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and reproductive indexes were analyzed.</p><p><b>RESULTS</b>ATO-treated mice showed a significantly decreased sperm count and testis somatic index and activity levels of SOD, GSH, and T-AOC than control group. Compared to the ATO-treated group, ATO +GSPE group showed recovery of the measured parameters. Mice treated with ATO+high-dose GSPE showed the highest level of mRNA expression of Nrf2, HO, NQO1, and GST.</p><p><b>CONCLUSION</b>GSPE alleviates oxidative stress damage in mouse testis by activating Nrf2 signaling, thus counteracting arsenic-induced reproductive toxicity.</p>