ABSTRACT
Objective To evaluate the role of protein kinase Ca (PKCα) in electroacupuncture (EA)-induced reduction of acute kidney injury (AKI) induced by endotoxic shock,and the relationship with nuclear factor E2-related factor 2/heme oxygenase-1 Nrf2/HO-1 pathway in rabbits.Methods Eighty heahhy male New Zealand white rabbits,aged 2 months,weighing 1.5-2.0 kg,were randomly divided into 8 groups (n=10 each) using a random number table:sham operation group (group S),group AKI,specific PKCα inhibitor chelerythrine + AKI group (group CHA),chelerythrine group (group Che),dimethyl sulfoxide (DMSO) group (group D),EA at acupoints + AKI group (group EA),EA at non-acupoints + AKI group (group SEA),and EA at acupoints + chelerythrine + AKI group (group CEA).Bilateral 30 min EA (disperse-dense wave,wave length 0.2-0.6 ms,frequency 2/15 Hz,intensity 1-2 mA) stimulation of Zusanli and Shenshu acupoints was performed once a day for 4 days before establishment of the model and during the process of establishment of the model in EA and CEA groups.In group SEA,EA was performed at the points 0.5 cm lateral to the acupoints of Zusanli and Shenshu with the same parameters.The animals were anesthetized with iv 20% urethane 5 ml/kg,tracheostomized and kept spontaneous breathing.Lipopolysaccharide 5 mg/kg (in 2 ml of normal saline) was injected via the auricular vein to establish the model of endotoxic shock-induced AKI in AKI,CHA,EA,SEA and CEA groups,while the equal volume of normal saline was given in S,Che and D groups.At 30 min before establishment of the model,chelerythrine 5 mg/kg (in 0.5 ml of 1% DMSO) was injected intravenously in CHA and CEA groups,the equal volume of chelerythrine was given in Che group,while the equal volume of DMSO was given in group D.At 6 h after lipopolysaccharide or normal saline injection,blood samples were taken from the internal carotid artery for determination of serum urea nitrogen (BUN) and creatinine (Cr) concentrations.The rabbits were then sacrificed by exsanguinations.The kidney specimens were removed for microscopic examination of pathologic changes which were scored and for determination of superoxide dismutase (SOD) activities,malondialdehyde (MDA) contents,and expression of PKCα protein and HO-1 protein,and expression of Nrf2 in nucleoprotein and total protein.Results Compared with group S,the serum BUN and Cr concentrations were significantly increased,MDA contents were increased,the activities of SOD were decreased,the kidney injury scores were increased,and the expression of PKCα protein,HO-1 protein,and Nrf2 in nucleoprotein and total protein was up-regulated in AKI,CHA,EA,SEA and CEA groups.Compared with group AKI,the serum BUN and Cr concentrations were significantly decreased,MDA contents were decreased,the activities of SOD were increased,the kidney injury scores were decreased,and the expression of PKCα protein,HO-1 protein,and Nrf2 in nucleoprotein and total protein was up-regulated in group EA,and the serum BUN and Cr concentrations were significantly increased,MDA contents were increased,the activities of SOD were decreased,the kidney injury scores were increased,and the expression of PKCα protein,HO-1 protein,and Nrf2 in nucleoprotein and total protein was down-regulated in CHA and CEA groups.The serum BUN and Cr concentrations were significantly higher,MDA contents were higher,the activities of SOD were lower,the kidney injury scores were higher,and the expression of PKCα protein,HO-1 protein,and Nrf2 in nucleoprotein and total protein was lower in group CEA than in group EA,and in CHA group than in CEA group.Conclusion PKCα mediates reduction of endotoxic shock-induced AKI by EA of Zusanli and Shenshu acupoints in rabbits,and the mechanism may be related to activation of Nrf2/HO-1.
ABSTRACT
Objective To investigate the effect of electro-acupuncture (EA) on nuclear factor E2-related factor 2 (Nrf2) expression in the renal tissues of rabbits with endotoxic shock-induced acute kidney injury (AKI) and the relationship with p38 mitogen-activated protein kinase (p38MAPK) signaling pathway.Methods Seventy male New Zealand white rabbits,weighing 1.5-2.0 kg,aged 2 months,were randomized into 7 groups (n =10 each) using a random number table:normal control group (C group),endotoxic shock-induced AKI group (AKI group),EA + endotoxic shock-induced AKI group (EA group),non-acupoints + endotoxic shock-induced AKI group (SA group),EA + endotoxic shock-induced AKI + specific p38MAPK blocker SB203580 group (EAS group),SB203580 group (S group),and ethanol group (A group).EA (intensity 1-2 mA,frequency 2/100 Hz,wave length 0.2-0.6 ms) of Zusanli and Shenyu lasting for 15 min was performed once a day for 5 consecutive days in EA and EAS groups.In SA group,EA was performed at the points 0.5 cm lateral to the acupoints of bilateral Zusanli and Shenyu using the parameters of EA mentioned above.At 24 h after the last EA,endotoxic shock-induced AKI was induced by injection of lipopolysaccharide (LPS) 5 mg/kg (in 2 ml normal saline) in AKI,EA,SA and EAS groups,while the equal volume of normal saline was given in the other groups.At 30 min before the model was established,5/μmol/kg SB203580 (in 0.5 ml ethanol) was injected intravenously in EAS and S groups,while ethanol 0.5 ml was given in A group and the equal volume of normal saline was given in the other groups.Blood samples were obtained at 6 h after administration of LPS or normal saline for determination of serum urea nitrogen (BUN) and creatinine (Cr) concentrations.The animals were sacrificed and kidney specimens were obtained for microscopic examination of pathological changes which were scored and for measurement of Nrf2 protein expression and phosphorylation of p38MAPK (by Western blot) and Nrf2 mRNA expression (using fluorescent quantitative PCR).Results Compared with C group,the pathological score and serum BUN and Cr concentrations were significantly increased,and Nrf2 mRNA and protein expression was up-regulated in AKI,EA,SA and EAS groups,the phosphorylation of p38MAPK was increased in AKI,EA and SA groups,and no significant changes were found in the parameters mentioned above in S and A groups.Compared with AKI group,the pathological score and serum BUN and Cr concentrations were significantly decreased,and Nrf2 mRNA and protein expression was up-regulated in EA and EAS groups,the phosphorylation of p38MAPK was increased in EA group,the phosphorylation of p38MAPK was decreased in EAS group,and no significant changes were found in the parameters mentioned above in SA group.Compared with EA group,the pathological score and serum BUN and Cr concentrations were significantly increased,Nrf2 mRNA and protein expression was down-regulated,and the phosphorylation of p38MAPK was decreased in EAS group.Conclusion The mechanism by which EA mitigates endotoxic shock-induced AKI may be related to activation of p38MAPK signaling pathway and up-regulation of Nrf2 expression in renal tissues of rabbits.
ABSTRACT
Objective To evaluate the role of activator protein-1 (AP-1 ) in electro-acupuncture (EA )-induced up-regulation of heme oxygenase-1 (HO-1 ) expression in lung tissues in a rabbit model of endotoxic shock .Methods Seventy healthy male New Zealand white rabbits ,aged 2 months ,weighing 1.5-2.0 kg ,were randomly divided into 7 groups ( n=10 each ) using a random number table :normal control group (group C ) , endotoxic shock-induced acute lung injury (ALI ) group (group ALI ) , EA + ALI group (group EL ) , non-acupoint+EA+ ALI group (group NEL ) , curcumin (HO-1 inhibitor ) group (group Cur ) , dimethyl sulfoxide group (group D ) ,and EA+ALI+curcumin group (group ELC ) .Bilateral 15 min EA stimulation of Zusanli and Feishu (according to atlas of animals acupoints ) was performed (frequency 15Hz ) once a day for 5 consecutive days before lipopolysaccharide (LPS ) administration in EL and ELC groups ,while in group NEL ,EA stimulation was performed at non-acupoints located 0.5 cm lateral to Zusanli and Feishu acupoints with the same parameters . The animals were anesthetized with urethane and tracheostomized .The animals kept spontaneous breathing .Right internal carotid artery was cannulated for blood pressure monitoring . Ear vein was cannulated for drug administration .At 5 days after EA stimulation ,curcumin 25 mg/kg (in 0.5 ml of 0.1% dimethyl sulfoxide ) was injected in Cur and ELC groups ,0.1% dimethyl sulfoxide 0.5 ml was injected in D group ,and the equal volume of normal saline was given in the other groups .LPS 5 mg/kg (in 2 ml of 0.9% normal saline ) was injected intravenously at 30 min after administration in ALI ,EL ,NEL and ELC groups ,while the equal volume of normal saline was given in the other three groups .Endotoxic shock was confirmed by decrease in mean arterial pressure to 75% of the baseline value within 2 h after LPS injection .Blood samples were collected from the common carotid artery at 6 h after LPS or normal saline administration and the rabbits were then sacrificed .The lungs were removed for microscopic examination and the pathological changes were scored .The wet/dry lung weight ratio (W/D ratio ) was calculated .The malondialdehyde (MDA ) content and superoxide dismutase (SOD ) activity in lung tissues were detected ,and the expression of HO-1 mRNA ,HO-1 ,c-Jun mRNA and c-Jun in lung tissues was determined by Western blot .Results Compared with group C ,the pathological score ,W/D ratio and MDA content were significantly increased ,and the SOD activity was decreased in ALI ,EL ,NEL and ELC groups ,the expression of HO-1 mRNA ,HO-1 ,c-Jun mRNA and c-Jun was up-regulated in groups ALI ,EL and NEL ( P0.05) .There was no significant difference in the parameters mentioned above between Cur and D groups ( P>0.05 ) .Compared with group ALI ,the pathological score ,W/D ratio and MDA content were significantly decreased ,and SOD activity was increased ,and the expression of HO-1 mRNA and HO-1 was up-regulated in EL and ELC groups ( P0.05) .The pathological score ,W/D ratio and MDA content were significantly higher ,and the SOD activity and expression of HO-1 mRNA ,HO-1 ,c-Jun mRNA and c-Jun were lower in group ELC than in group EL ( P<0.05) .Conclusion EA up-regulates HO-1 expression through activating AP-1 during endotoxic shock-induced ALI in rabbits ,thus protecting the lung .
ABSTRACT
Heme oxygenase (HO)-1 has been reported to play a great role in attenuating lung injury during endotoxic shock in our previous research. Although electro-acupuncture has been explored to reduce oxidative stress and decrease inflammatory reaction in animals with endotoxic shock, the mechanism of this effect is still unclear. The aim of this study was to determine whether HO-1 is involved in the effect of electro-acupuncture on the injured lung during endotoxic shock in rabbits. Sixty New England white rabbits were randomly divided into groups C, Z, ES, EA, AP, and EAZ. Before inducing endotoxic shock, group ES received no electro-acupuncture, while group EA received electro-acupuncture at ST36 (zusanli) and BL13 (feishu) acupoints on both sides for five days and group AP received electro-acupuncture (EA) stimulation at a non-acupoint. Groups ES, AP, EA, and EAZ received LPS to replicate the experimental model of injured lung induced by endotoxic shock, and electro-acupuncture was performed throughout the procedure with the same parameter. Groups EAZ and Z received the HO-1 inhibitor, ZnPP-IX, intraperitoneally. The animals were sacrificed by blood-letting at 6 h after LPS administration. The blood samples were collected for serum examination, and the lungs were removed for pathology examination, detection of alveolaer epithelial cell apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL assay), determination of wet to dry ratio, measurement of Evans blue (EB) contents, and determination of HO-1protein and mRNA expression. According to the results, EA at ST36 and BL13 could increase the expression of HO-1. At the same time, index of quantitative assessment (IQA) score and the number of TUNEL-positive cells decreased, while electro-acupuncture at the other points did not exert this effect, and pretreatment with ZnPP-IX in group EAZ suppressed the efficacy of electro-acupuncture preconditioning. In summary, electro-acupuncture stimulation at ST36 and BL13, while not the non-acupoint, could attenuate the lung injury during the endotoxic shock, and this effect was due to increased expression of HO-1.
Subject(s)
Acupuncture Therapy , Acute Lung Injury/therapy , Endotoxins/pharmacology , Heme Oxygenase-1/metabolism , Shock, Septic/chemically induced , Acupuncture Therapy/methods , Acute Lung Injury/etiology , Animals , Disease Models, Animal , Electric Stimulation/methods , Heme Oxygenase-1/antagonists & inhibitors , Male , Malondialdehyde/blood , Oxidative Stress/drug effects , RabbitsABSTRACT
Objective To evaluate the effect of electro-acupuncture (EA) at Zusanli and Feishu on endotoxin shock-induced acute lung injury in rabbits.Methods Sixty healthy male New Zealand white rabbits aged 2 months weighing 1.5-2.0 kg were randomly divided into 6 groups (n =10 each):group sham operation (group S); group zinc protoporphyrin-Ⅸ (ZnPP-Ⅸ) (group Z); group lipopolysaccharide (LPS) (group L); group LPS + EA (group EL) ; group LPS + sham EA (group SEL) and group LPS + EA + ZnPP-Ⅸ (group ELZ).The animals were anesthetized with intraperitoneal 10% chloral hydrate 400 mg/kg and tracheostomized.The animals kept spontaneous breathing.Right internal carotid artery was cannulated for BP monitoring.Ear vein was cannulated for drug administration.LPS 5 mg/kg was injected iv in groups L,EL,SEL,ELZ.Endotoxin shock was confirmed by decrease in BP by 20 % of the baseline value and PaO2/FiO2 ≤ 300.ZnPP-Ⅸ (heme oxygenase (HO-1 ) inhibitor)10μmol/kg was injected intraperitoneal at 2 h after LPS injection in groups Z and ELZ.Bilateral 15 min EA stimulation of Zusanli and Feishu ( according to atlas of animal acu-points) was performed once a day for 5 days before LPS administration in groups EL and ELZ.The animals were sacrificed by blood-letting at 6 h after LPS administration.The lungs were removed for microscopic examination (0 =no injury,4 =most severe injury),detection of alveolar epithelial cell apoptosis (by TUNEL) and determination of HO-1 protein and mRNA expression.Results LPS significantly increased lung injury scores,alveolar epithelial cell apoptosis index (the number of apoptotic cells/total cells) and HO-1 protein and mRNA expression.EA significantly attenuated lung injury and alveolar epithelial cell apoptosis induced by LPS and further increased the expression of HO-1 protein and mRNA in group EL as compared with group L.The protective effects of EA was counteracted by ZnPP- Ⅸ in group ELZ.Conclusion EA at Zusanli and Feishu can attenuate endotoxin shock-induced lung injury by up-regulation of HO-1 expression and inhibiting alveolar epithelial cell apoptosis in the lung.