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Objective To evaluate the effect of tert-butylhydroquinone ( t-BHQ) on DJ-1∕nuclear factor erythroid 2-related factor 2 (Nrf2) pathway during renal ischemia-reperfusion (I∕R) in diabetic rats. Methods Forty SPF healthy adult male Sprague-Dawley rats, weighing 200-220 g, were divided into 4 groups (n＝10 each) using a random number table method: control group (group C), diabetes mellitus group (group D), diabetes mellitus plus renal I∕R group (I∕R group) and t-BHQ group (group T). Diabe-tes mellitus was induced by intraperitoneal streptozotocin 60 mg∕kg and confirmed by fasting blood glucose level＞16. 7 mmol∕L 72 h later. t-BHQ 50 mg∕kg was intraperitoneally injected in 3 times at an interval of 8 h starting from 24 h before surgery in group T, while the equal volume of normal saline was given instead in D and I∕R groups. Blood samples were collected from the apex of the heart at 24 h of reperfusion for deter-mination of serum creatinine (Cr), cystatin C (Cys C) and β2-microglobulin (β2-MG) concentrations. The rats were then sacrificed, and kidneys were removed for determination of pathological changes of kidneys (with a light microscope) and for detection of the expression of DJ-1, Nrf2 and heme oxygenase-1 (HO-1) in renal tissues (by Western blot). Results Compared with group C, the concentrations of serum Cr, Cys C and β2-MG and pathological scores were significantly increased, and the expression of DJ-1, Nrf2 and HO-1 was up-regulated in D, I∕R and T groups ( P＜0. 05). Compared with group D and group I∕R, the concentrations of serum Cr, Cys C and β2-MG and pathological scores were significantly decreased, and the expression of DJ-1, Nrf2 and HO-1 was up-regulated in group T ( P＜0. 05). Conclusion t-BHQ can at- tenuate renal I∕R injury by activating DJ-1∕Nrf2 pathway in diabetic rats.
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Objective:Preliminary study on rats with delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) model intervention agent tBHQ before and after the nuclear factor E2-related factor 2(Nrf2) and its downstream target genes of heme oxygenase 1(HO-1) change in hippocampus associated,in order to further study the pathogenesis of DEACMP,at the same time for the targeted therapy of provide a certain experimental basis.Methods: One hundred and twenty rats were randomly divided into carbon monoxide poisoning group(CO group),air control group(AC group),carbon monoxide+3% ethanol group(EC group),carbon monoxide+tBHQ group(group TC),then the rats in exposure after 1 d,3 d,7 d,14 d,21 d,28 d,with the machine was divided into 6 sub groups,followed by the Morris water maze test to observe the behavior of rats,immunohistochemistry and protein Western blot method of chemical(Western blot) detecting expression of Nrf2 and HO-1 mploying intervention agent tBHQ before and after,and then TUNEL staining was detected cell apoptosis.Results: CO group,EC group,TC group Nrf2 in hippocampus of rats and the expression of HO-1 were increased in the first day and reach a peak at the third day,then gradually decreased,and at each time point in AC group were statistically significant,TC group and CO group Nrf2 and HO-1 were increased in each sub group and the deffirences were statistically meaning.Comparison apoptotic cells in CO group,EC group,TC group with AC group rats increased significantly over time,and showed higher peak(7-14 d)-decreased.TC group compared with CO group,the apoptotic cells(7-14 d) decreased,the difference was statistically significant.Conclusion: The Nrf2/ARE/HO-1 pathway plays an important role in the development of DEACMP,and the tBHQ specific activation of the Nrf2 pathway achieves early protection and is expected to reduce or mitigate DEACMP.
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Objective To investigate the expression of 6-phosphofructo-2-kinase /fructose-2,6-bisphosphatase-3 (PFKFB3) and sphingosine 1-phosphate receptor 2 (S1 P2) in the retina of rats with type 2 diabetes mellitus (DM) and to explore the correlation of tertiary butylhydroquinone (tBHQ) with PFKFB3 and S1P2.Methods Together 60 male SD rats were divided into normal control group (NC group),diabetes mellitus group (DM group) and tBHQ group.Type 2 DM model was induced in the latter two groups.The rats in tBHQ group were given 10 g · L-1 tBHQ in high-fat and highsugar diet 1 week after successful modeling,while DM rats were fed with high-fat and high-sugar diet continuously.At 4 weeks and 12 weeks after tBHQ intervention,blood samples were taken from the hearts of rats in each group,and serum contents of fasting plasma glucose (FPG) and fasting serum insulin (FINs) were measured.Immunohistochemistry and qRT-PCR were taken to detect the distribution and expression of PFKFB3,S1 P2 and vascular endothehal growth factor (VEGF) mRNA and protein in the retina,and TUNEL methods were used to detect apoptosis index of retinal ganglion cells of rats in each group.Results There were significant difference in the FPG and FINs levels of the three groups at 4 weeks and 12 weeks (all P =0.000).Light microscopy test showed that positive expressions of PFKFB3,S1 P2 and VEGF protein were found in all groups at 4 and 12 weeks,which were mainly located in the retinal ganglion cell layer and the inner nuclear layer.Immunohistochemistry and qRT-PCR showed that the difference in relative expressions of PFKFB3,S1P2,VEGF protein and mRNA in the retina at different times after modeling were statistically significant (all P ＜ 0.05).At 4 and 12 weeks,the expression levels of PFKFB3,S1P2 and VEGF in DM group were higher than those in NC group,but their expressions in tBHQ group were significantly downregulated when compared with DM group,and all differences were statistically significant (all P ＜ 0.05).Compared with 4 weeks,PFKFB3,S1 P2 and VEGF mRNA and protein in DM group were overexpressed at 12 weeks,and the expression level of S1 P2 in tBHQ group at 12 weeks was lower than that at 4 weeks,and the differences were statistically significant (all P ＜ 0.05).TUNEL assays showed that there was significant difference in the apoptotic index (AI) of retinal ganglion cells of rats in each group at different times after modeling (all P ＜ 0.05).DM group had higher AI than NC group (P ＜ 0.05),and tBHQ group was lower than DM group (P ＜ 0.05);Compared with 4 weeks,DM group had increased AI at 12 weeks while tBHQ group had decreased AI (both P ＜ 0.05).Conclusion PFKFB3,S1P2 and VEGF are involved in the pathological process of the retina of type 2 DM rats,which may play a role through the PFKFB3 / VEGF / S1P2 signaling pathway and may be related to the apoptosis of retinal ganglion cells.And it is indicated that tBHQ has a protective effect on the retina of type 2 DM rats.
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Objective To investigate the effect of nuclear factor erythroid 2-related factor 2(Nrf2)-autophagy pathway on the incisional pain-remifentanil-induced hyperalgesia of rat model. Methods Twenty-four male Sprague-Dawley rats were randomly allocated into three groups:saline+incisional pain group(group I),remifentanil+incisional pain group(group RI)and Nrf2 agonist t-BHQ group(group tBHQ),with 8 rats in each group.In group I and RI,normal saline at 0.1 mL/(kg· min) and remifentanilat 1 μg/(kg·min) were respectively infused into caudal vein for 60 min. Rats in group t-BHQ were injected intraperitoneally with Nrf2 agonist t-BHQ(15 mg/kg),the first time at 0.5 h before remifentanil infusion,per 12 h once,4 times in a row,the rest management was the same as group RI.Brennan incision pain model rats were constructed along with the infusions in the three groups. The thermal paw withdraw latency (PWL) and mechanical paw withdraw threshold(PWT)were measured at 24 h before the infusion(T0)and at 2 h(T1),6 h(T2),24 h(T3),48 h(T4)after the infusion. Rats were sacrificed after the tests, then the L4-6segments of signal cord were removed and the expression levels of autophagy-related proteins,microtubule associated protein 1 light chain 3Ⅱ(LC3Ⅱ),Beclin 1,Nrf2 and Nrf2 downstream molecular hemeoxygenase-1 (HO-1) were detected by Western blot assay. Results The PWT and PWL values were decreased significantly with the prolongation of the processing time in the three groups. Compared with group I, PWL and PWT values were decreased at T1-4,the expression levels of LC3Ⅱand Beclin-1 were increased while Nrf2 and HO-1 were decreased at T4in group RI (P<0.05). While compared with group RI, PWL and PWT values were increased, and the expressions of Nrf2 and HO-1 were increased, LC3Ⅱ and Beclin-1 protein were upregulated in group tBHQ (P<0.05).Conclusion The activation of Nrf2-autophagy pathway can improve the incisional pain-remifentanil induced hyperalgesia.
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[Objective] To investigate the effects and mechanisms of Nrf2-ARE (nuclear factor erythroid-2 related factor-anti-oxidant response element) pathway on uremic serum-mediated endothelial dysfunction in human aortic endothelial ceils.[Methods] Human aortic endothelial cells were incubated in endothelial cell medium containing 10％ normal serum,10％ non-diabetic nuremic serum or 10％ diabetic uremic serum respectively,and 20 μmol/L tertiary butyl hydroquinone (tBHQ) were pretreated with cells to active Nrf2-ARE pathway.The cells apoptosis rate were measured by flow cytometry,and the synthesis of NO was detected by flow cytometry and immune fluorescent confocal,while the expression of P-eNOSer1177/eNOS,and quinone oxidoreductase-1 (NQO1) were measured by western blotting.The levels of malondialdehyde,superoxide dismutase,eatalase,and glutathione in these cells were also measured with kits.[Results] Aortic endothelial cells incubated with uremic serum had a higher level of apoptosis rate and MDA (P ＜ 0.05),and a lower level of NO systhesis,P-eNOSSer1177/eNOS expression,CAT,SOD,GSH (P ＜ 0.05).Pretreated with tBHQ can reduce the apoptosis rate and MDA level (P ＜ 0.05),improve the amount of NO systhesis,the expression of P-eNOSSer1177/eNOS,the levels of CAT,SOD,and GSH in these cells (P ＜ 0.05).[Conclusion] Activation of Nrf2-ARE pathway can improve endothelial dysfunction in aortic endothelial cells induced by uremic serum,and its mechanism might be related with enhancement of the antioxidant stress.
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Objective To study the protective effects of tBHQ on type 2 diabetic rats retina and its related mechanism.Methods Sixty SD rats were divided into normal control group (NC group),model group (diabetes mellitus,DM group) and tBHQ group.After feeding with high fat and high sugar diets for 4 weeks,the rats in model group were induced by intraperitoneal injection of STZ for the model of type 2 diabetes mellitus.1％ tBHQ were added into the high fat and high sugar feed 1 week later after successfully modeled in the tBHQ group.Fasting plasma glucose (FPG) and fasting serum insulin (FINs) were detected at 4 and 12 weeks after modeled.Immunohistochemical method and real-time fluorescent quantitative PCR (qRT-PCR) were respectively used to detect the distributions and relative expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2),heme oxygenase 1 (HO-1),B-cell lymPhoma 2 (Bcl-2) and vascular endothelial growth factor (VEGF) in retinas of the rats.Results FPG levels totally comparative differences were statistically significant between each group (F =78.531,P =0.000).The level of FPG in DM and tBHQ group were obviously higher than that in NC group,the 12 weeks was higher than 4 weeks in DM group,and the 12 weeks was lower than 4 weeks in tBHQ group (all P ＜ 0.05).Totally comparative differences in the level of FINs were statistically significant (F=22.480,P =0.000),NC group was lower than DM and tBHQ group,12 weeks was higher than 4 weeks (all P ＜ 0.05).Immunohistochemical detection showed that each factor in each group were expressed in the retina of rat,and the relative expressions of Nrf2,HO-1,Bcl-2 and VEGF protein in retina have totally statistically differences in different time points after modeled (all P ＜0.05).The expressions of each factor in DM group were more than those in the NC group.The Nrf2,HO-1 and Bcl-2 in tBHQ group were more than those in the DM group,but the VEGF was lower.At 12 weeks,the expressions of VEGF and Nrf2 in DM group were more than those at 4 weeks,but the HO-1 was lower;the Nrf2,HO-1 and Bcl-2 in tBHQ group were more than those at 4 weeks (all P ＜ 0.05).PCR tests revealed that the relative expressions of Nrf2,HO-1,Bcl-2 and VEGF mRNA in retina have totally statistically differences in different time points after modeled(all P ＜ 0.05).The expressions of each factor in DM group were more than those in the NC group.The Nrf2,HO-1 and Bcl-2 mRNA in tBHQ group were more than those in the DM group,but the VEGF mRNA was lower.At 12 weeks,VEGF mRNA in DM group and Nrf2,HO-1,Bcl-2 in tBHQ group were more than those at 4 weeks (all P ＜ 0.05).Conclusion tBHQ maybe have protection for islet function on diabetic rat,and can induce the expressions of Nrf2,HO-1,Bcl-2 in retina of diabetic rats and reduce the expression of VEGF,inhibit the oxidative stress of retinal tissue damage,reduce cell apoptosis and inhibit the proliferation of retinal blood vessels.tBHQ may protect the retina of diabetic rats through the Nrf2/HO-1/VEGF and Nrf2/Bcl-2 way.
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Objective@#To study the protective effects and possible mechanisms of tBHQ in rats exposed to acute silicadust.@*Methods@#Male Wistar rats without specific pathogen SPF were randomly divided into control group、model group and intervention group, 32 rats for each group. Rats in the model group and the intervention group were treated with a single non exposed tracheal dust method to establish the rats exposed to silica model. The intervention group was intervened with 1% tBHQ solution, once a day. Each group 8 rats were sacrificed at 3,14,28,60d, respectively.The contents of IL-1,TNF-α, HYP,TGF-β in the lung tissue of rats were determined by enzyme linked immunosorbent assay(ELISA), the contents of MDA and the GSH-PX activity in lung tissue and serum of rats were determined by colorimetry.@*Results@#Compared with the control group, the contents of IL-1 in the lung tissue of the model group and the intervention group at each time point increased with time, the contents of IL-1 of model group reached the maximum at 60d, the contents of IL-1 in intervention group reached the maximum at 28d(P<0.05), except 3 d. Compared with the control group, the contents of TGF-β and HYP in the lung tissue of the model group and the intervention group at 28 and 60 d increased with time and reached the maximum at 60d(P<0.05). Compared with the model group at each time point, the contents of IL-1, TGF-β, HYP in the intervention group were lower than those in the model group(P<0.05). Compared with the control group, the contents of MDA in lung tissue and serum of rats in model group and intervention group at different time points increased with time(P<0.05). Compared with the control group,the activity of GSH-PX in serum and lung tissue of rats in model group and intervention group decreased with time,there was no significant difference in 3d(P<0.05), compared with the control group, the activity of GSH-PX in the lung and serum tissue of in-tervenetion group was higher than model group except the 3d(P<0.05).@*Conclusion@#The intervention of tBHQ can alleviate oxidative stress in rats exposed to silica dust to some extent, improve the antioxidant capacity of the body, and reduce the contents of IL-1, TNF-α, TGF-β,HYP in lung tissue,it has acertain impediment and inhibition effect on the inflammation and fibrosis caused by acute silica dust exposure.
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Objectives To investigate the protective effects and mechanism of antioxidant TBHQ on renal damage caused by doxorubicin chemotherapy in mice with hepatic cancer. Methods Cell H22 of mice with hepatic cancer which was subcultured for three times was subcutaneously transplanted to the groin of right lower limb of 45 SPF Kunming mice to establish the transplanted tumor model. The doxorubicin chemotherapy group and antioxidant intervention group received intraperitoneal injection of ADM (1 mg/kg·0.2 mL/2 d). The model control group received normal saline (NS) of the same volume at the same time. 1% TBHQ was added into the diet of mice of the antioxidant intervention group. Seven weeks later, morning urines and peripheral blood were randomly collected to detect UAlb, UCr, BUN, Scr and UAlb/Cr levels. All mice were beheaded. The renal tissues were made into homogenate, and SOD, T-AOC and MDA content in tissues were detected followed by cell lysis. All data were processed using SPSS19.0. Results The UAlb/Cr, BUN, Scr and MDA of doxorubicin chemotherapy group were significantly higher those of model control group and the activities of SOD, T-AOC in doxorubicin chemotherapy group were lower than those of model control group (P < 0.01). The UAlb/Cr, BUN, Scr and MDA of antioxidant intervention group were lower than those of doxorubicin chemotherapy group and the activities of SOD, T-AOC of antioxidant intervention group were higher than those of doxorubicin chemotherapy group doxorubicin chemotherapy group (P < 0.05). The BUN of model control group was higher than that of blank group, and T-AOC was lower than that of blank group, and difference was statistically significant (P < 0.05). Conclusions Doxorubicin chemotherapy could lead to abnormal antioxidant capacity and renal function of tumor-bearing mice with hepatic cancer. TBHQ antioxidant intervention could effectively improve the antioxidant capacity of renal tissue and reduce the renal damage caused by doxorubicin to some extent.
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OBJECTIVES@#To investigate the protective effects and mechanism of antioxidant TBHQ on renal damage caused by doxorubicin chemotherapy in mice with hepatic cancer.@*METHODS@#Cell H22 of mice with hepatic cancer which was subcultured for three times was subcutaneously transplanted to the groin of right lower limb of 45 SPF Kunming mice to establish the transplanted tumor model. The doxorubicin chemotherapy group and antioxidant intervention group received intraperitoneal injection of ADM (1 mg/kg·0.2 mL/2 d). The model control group received normal saline (NS) of the same volume at the same time. 1% TBHQ was added into the diet of mice of the antioxidant intervention group. Seven weeks later, morning urines and peripheral blood were randomly collected to detect UAlb, UCr, BUN, Scr and UAlb/Cr levels. All mice were beheaded. The renal tissues were made into homogenate, and SOD, T-AOC and MDA content in tissues were detected followed by cell lysis. All data were processed using SPSS19.0.@*RESULTS@#The UAlb/Cr, BUN, Scr and MDA of doxorubicin chemotherapy group were significantly higher those of model control group and the activities of SOD, T-AOC in doxorubicin chemotherapy group were lower than those of model control group (P < 0.01). The UAlb/Cr, BUN, Scr and MDA of antioxidant intervention group were lower than those of doxorubicin chemotherapy group and the activities of SOD, T-AOC of antioxidant intervention group were higher than those of doxorubicin chemotherapy group doxorubicin chemotherapy group (P < 0.05). The BUN of model control group was higher than that of blank group, and T-AOC was lower than that of blank group, and difference was statistically significant (P < 0.05).@*CONCLUSIONS@#Doxorubicin chemotherapy could lead to abnormal antioxidant capacity and renal function of tumor-bearing mice with hepatic cancer. TBHQ antioxidant intervention could effectively improve the antioxidant capacity of renal tissue and reduce the renal damage caused by doxorubicin to some extent.