ABSTRACT
Objective To evaluate the role of glycogen synthase kinase 3 beta (GSK-3β) in lipid emulsion-induced inhibition of bupivacaine-induced apoptosis in cardiomyocytes of rats using RNA interference (RNAi) adenovirus infection method.Methods H9C2 cells were transferred into 96-well cell plates at a density of 1× 105 cells/ml after culture and then divided into 8 groups (n =10 each) using a random number table:control group (group C),bupivacaine group (group B),lipid emulsion group (group LE),bupivacaine plus lipid emulsion group (group B+LE),control plus GSK-3βRNAi adenovirus (GSK-3βi) group (group C+GSK-3βi),bupivacaine plus GSK-3βi group (group B+GSK-3βi),lipid emulsion plus GSK-3βi group (group LE+GSK-3βi) and bupivacaine plus lipid emulsion plus GSK-3βi group (group B+LE+GSK-3βi).ln B,LE and B+LE groups,the cells were incubated with culture medium containing 1 mmol/L bupivacaine,1％ lipid emulsion and 1 mmol/L bupivacaine plus 1％ lipid emulsion,respectively.In C+GSK-3βi,B+GSK-3βi,LE+GSK-3βi and B+LE+GSK-3βi groups,the cells were incubated with the drugs mentioned above on 2nd day after being infected by adenovirus.At 24 h after incubation with drugs,the expression of Bax and Bcl-2 was determined by Western blot,and the apoptosis rate was calculated using DAPI staining.Results Compared with group C,the expression of Bax was significantly upregulated,the expression of Bcl-2 was down-regulated,and the apoptosis rate was increased in group B (P＜0.05).Compared with group B,the expression of Bax was significantly down-regulated,the expression of Bcl-2 was up-regulated,and the apoptosis rate was decreased in group B+LE (P＜0.05).Compared with group B+LE,the expression of Bax was significantly up-regulated,the expression of Bcl-2 was downregulated and the apoptosis rate was increased in group B+LE+GSK-3βi (P＜0.05).Conclusion The mechanism by which lipid emulsion inhibits bupivacaine-induced apoptosis in cardiomyocytes of rats is associated with GSK-33.
ABSTRACT
Objective To evaluate the effect of mitochondrial permeability transition pore (mPTP) in lipid emulsion-induced inversion of bupivacaine myocardiotoxicity in rats.Methods H9c2 cells were inoculated in 6-well plates at a density of 105 cells/ml, and were randomly divided into 4 groups (6 wells in each group, 2 ml/well) using a random number table: control group (group C) , bupivacaine group (group B) , lipid emusion + bupivacaine group (group LB) , and lipid emusion + bupivacaine + atractyloside group (group LBA).Phosphate buffer solution 100 μl was added to the culture medium in group C.In group B, bupivacaine was added to the culture medium with the final concentration of 1 mmol/L.In group LB, lipid emusion and bupivacaine were added to the culture medium with the final concentrations of 1％ and 1 mmol/L, respectively.In group LBA, lipid emusion, bupivacaine and atractyloside (an mPTP opener) were added to the culture medium with the final concentrations of 1％, 1 mmol/L and 30 μmol/L, respectively.All the cells were incubated for 24 h.After the end of incubation, the expression of Bcl-2, Bax, phosphorylated Bad (p-Bad) , caspase-3, activated caspase-3, caspase-9,activated caspase-9 and cytochrome c (Cyt c) was detected using Western blot.The expression of Bcl-2 mRNA, Bax mRNA, Bad mRNA, caspase-9 mRNA and Cyt c mRNA was detected using real-time reverse transcriptase polymerase chain reaction.The ratios of Bax/Bcl-2, activated caspase-3/caspase-3, activated caspase-9/caspase-9, and Bax mRNA/Bcl-2 mRNA were calculated.Results Compared with group C,the ratios of Bax/Bcl-2, activated caspase-3/caspase-3, activated caspase-9/caspase-9, and Bax mRNA/ Bcl-2 mRNA were significantly increased, the expression of p-Bad was down-regulated, and the expression of Cyt c, Bad mRNA, caspase-9 mRNA and Cyt c mRNA was up-regulated in group B (P＜0.05) , and no significant change was found in the parameters mentioned above in group LB (P＞0.05).Compared with group B, the ratios of Bax/Bcl-2, activated caspase-3/caspase-3, activated caspase-9/caspase-9, and Bax mRNA/Bcl-2 mRNA were significantly decreased, the expression of p-Bad was up-regulated, and the expression of Cyt c, Bad mRNA, caspase-9 mRNA and Cyt c mRNA was down-regulated in LB and LBA groups (P＜ 0.05).Compared with group LB, the ratios of Bax/Bcl-2, activated caspase-3/caspase-3, activated caspase-9/caspase-9, and Bax mRNA/Bcl-2 mRNA were significantly increased, the expression of p-Bad was down-regulated, and the expression of Cyt c, Bad mRNA, caspase-9 mRNA and Cyt c mRNA was up-regulated in group LBA (P ＜ 0.05).Conclusion The mechanism underlying lipid emulsioninduced inversion of bupivacaine myocardiotoxicity is related to inhibited mPTP opening in rats.
ABSTRACT
Objective To investigate the effect of lipid emulsion on mitochondrial energy metabolism during bupivacaine-induced myocardiotoxicity in rats.Methods H9c2 cells were inoculated in 96-well plates at a density of 1 × 105cells/ml, and were randomly divided into 4 groups (n =18 each) using a random number table: control group (group C) , bupivacaine group (group B) , lipid emulsion group (group LE) , and bupivacaine + lipid emulsion group (group B + LE).The cells were incubated in the normal culture medium in group C.In group LE, the cells were incubated in the culture medium containing 1％ lipid emulsion.In group B, the cells were incubated in the culture medium containing 1 mmol/L bupivacaine.In group B + LE, the cells were incubated in the culture medium containing 1 mmol/L bupivacaine and 1％ lipid emulsion.After 24 h of incubation, the contents of ATP, ADP, and AMP were measured by high-performance liquid chromatography, and apoptotic rate was calculated by Hoechst33342/ PI staining.Results Compared with group C, the contents of ATP, ADP and AMP were significantly decreased, and apoptotic rate was increased in group B (P＜0.05), and the contents of ATP and ADP in group LE and ATP content in group B + LE were increased, and no significant changes were found in apoptotic rate in LE and B+LE groups (P＞0.05).Compared with group C, the contents of ATP, ADP and AMP were significantly increased, and apoptotic rate was decreased in LE and B+LE groups (P＜ 0.05).Compared with group LE, the contents of ATP, ADP and AMP were significantly decreased (P＜ 0.05), and no significant change was found in apoptotic rate in group B+LE (P＞0.05).Conclusion The mechanism by which lipid emulsion reduces bupivacaine-induced myocardiotoxicity may be associated with improved mitochondrial energy metabolism in rats.