1. Detecting low density lipoprotein receptor mutant gene of rabbit by PCR
Academic Journal of Xi'an Jiaotong University 2006;18(2):199-201
Objective: Watanabe Heritable Hyperlipidaemic (WHHL) rabbits with low density lipoprotein receptor (LDLr) gene mutation have provided unprecedented opportunities for the study of human atherosclerosis, in order to confirm LDL receptor gene status in rabbits, we developed a simple PCR technique to detect LDL mutations in rabbits. Methods: Rabbits genomic DNA were extracted from ear biopsy, and amplified by PCR to detect 12 bp deletion mutation in WHHL rabbits. PCR products were directly digested with Bgl I, and then applied to polyacrylamide gel electrophoresis. Results: PCR products from homozygous LDLr +/+ rabbits generated 2 bands of 212 and 94 bp after Bgl I digestion, LDLr +/- rabbits generated 3 bands (294, 212, and 94 bp), LDLr -/-animals, however, generated only 1 product (294 bp). Conclusion: This modified PCR method is simple and reliable.
2.Activation of PPARαimproves PPARγ-induced fatty liver in the mouse
Liang BAI ; Rong WANG ; Xiao LUO ; Sihai ZHAO ; Enqi LIU
Acta Laboratorium Animalis Scientia Sinica 2015;(4):342-346
Object To investigate the effect of PPARαactivation on PPARγ-induced fatty liver in the mouse. Methods Wild type mice ( C57BL/6) aged 4 to 5 weeks were used as animal models.All mice were divided into four groups.The mice in the first group were fed with chow diet.The mice in the second group were fed with a diet containing 0.125%Wy-14,643, an agonist of PPARa, for 8 days.The mice in the third group were injected with Ad/PPARγvia tail vein for 5 day.The mice in the fourth group were firstly fed with Wy-14,643 diet for 3 days and then injected with Ad/PPARγvia tail vein for another 5 day.Mouse livers were collected and photographed.The effect of PPARαactivation on PPARγ-induced fatty liver was observed by H&E and Oil red O staining.Results Compared with the controls, wild-type mice treated with Wy-14,643 for 8 days exhibited marked hypertrophy of hepatocytes with increased cytoplasmic eosinophil-ia and proliferation of peroxisomes.The liver size was significantly increased in the wild-type mice treated with Ad/PPARγfor 5 days, and over-expression of PPARγstrongly induced hepatic steatosis.Importantly, the wild-type mice pretreated with Wy-14,643 for 3 days and then given Ad/PPARγinjection exhibited dramatically the increase of liver size, which might be due to the dual function of PPARa and PPARγ.Compared with the Ad/PPARγgroup, the Wy-14,643 pretreat-ment group showed a reduced hepatic steatosis.Conclusions Activation of PPARαby Wy-14,643 effectively improves PPARγ-stimulated hepatic steatosis, which provides a novel target for prevention and therapy of fatty liver.
3.DETECTING LOW DENSITY LIPOPROTEIN RECEPTOR MUTANT GENE OF RABBIT BY PCR
Enqi LIU ; Sihai ZHAO ; Zhenglan CHEN ; Penghui YANG
Journal of Pharmaceutical Analysis 2006;18(2):199-封3
Objective Watanabe Heritable Hyperlipidaemic (WHHL) rabbits with low density lipoprotein receptor (LDLr) gene mutation have provided unprecedented opportunities for the study of human atherosclerosis, in order to confirm LDL receptor gene status in rabbits, we developed a simple PCR technique to detect LDL mutations in rabbits. Methods Rabbits genomic DNA were extracted from ear biopsy, and amplified by PCR to detect 12 bp deletion mutation in WHHL rabbits. PCR products were directly digested with BglⅠ, and then applied to polyacrylamide gel electrophoresis. Results PCR products from homozygous LDLr +/+ rabbits generated 2 bands of 212 and 94 bp after BglⅠ digestion, LDLr +/- rabbits generated 3 bands (294, 212, and 94 bp), LDLr -/- animals, however, generated only 1 product (294 bp). Conclusion This modified PCR method is simple and reliable.
4.Establishment of cholesteryl ester transfer protein transgenic rabbits by DNA microinjection and analysis of their biological properties
Shoucui GAO ; Daxin CHENG ; Sihai ZHAO ; Yulong CHEN ; Xiaojing WANG ; Liang BAI ; Jianglin FAN ; Enqi LIU
Acta Laboratorium Animalis Scientia Sinica 2015;(4):331-335
Objective The aim of this study was to generate human cholesteryl ester transfer protein ( CETP) transgenic rabbits and analyze their biological properties.Methods We generated human CETP transgenic rabbits by DNA microinjection, and detected the expression of human CETP by real-time PCR and Western blot assay.The activity of CETP was measured using an activity assay kit.Results Human CETP transgenic rabbits were successfully generated by DNA microinjection.Compared with wide type rabbits, the expression of human CETP was dramatically increased in the liver of the human CETP transgenic rabbits.The plasma CETP activity was also much higher in the liver of human CETP transgenic rabbits than that of control rabbits.Conclusions The model of human CETP transgenic rabbits is successfully established by DNA microinjection.It will provide a useful tool for the studies of CETP biological function and its involvement in the mechanisms of cardiovascular diseases.
5.Correlation between plasma nitric oxide and atherosclerotic lesion in rabbits
Yanping BAI ; Yulong CHEN ; Yan LIN ; Ninghong ZHU ; Xiaoping XU ; Enqi LIU
Journal of Xi'an Jiaotong University(Medical Sciences) 2015;(2):180-185
ABSTRACT:Objective To analyze the correlation between plasma nitric oxide (NO)level and atherosclerotic lesion in high cholesterol-fed (HCD ) rabbits.Methods Twenty male Japanese white rabbits were divided randomly into two groups,which were fed with normal diet (control group,n =10)or HCD (experimental group, n =10 )for 1 6 weeks.At the end of the experiment,plasma lipid and NO levels were measured.The gross atherosclerotic lesions in each group were detected by Sudan IV staining while intimal lesion area was measured by hematoxylin/eosin (HE)and elastica van gieson (EVG).Moreover,the macrophages (MΦ)and smooth muscle cells (SMC)were detected by immunohistochemical staining.The correlation analysis was made to reveal the relationship between atherosclerotic lesions and plasma NO level.Results Compared with those in control group, the total cholesterol (TC),triglyceride (TG),low-density lipoprotein cholesterol (LDL-C)and NO levels all increased significantly in experimental group.Atherosclerotic lesions appeared on the vascular wall in the latter group.The area of atherosclerotic lesions and MΦ in the plaque had a positive association with plasma NO level. Conclusion There is a relationship between plasma NO level and the size of HCD-induced atherosclerotic lesions in rabbits.Meanwhile,the MΦ positive area in the atherosclerotic plaque is also associated with plasma NO level in cholesterol-fed rabbits,suggesting that plasma NO level may be associated with the occurrence and progress of early atherosclerosis.
6.Allicin suppresses atherosclerosis by up-regulating protein S-nitrosylation
Yan LIN ; Yulong CHEN ; Bingqiao HUANG ; Ninghong ZHU ; Peigang YANG ; Liang BAI ; Mengjun ZHAI ; Enqi LIU
Journal of Xi'an Jiaotong University(Medical Sciences) 2015;(3):310-316
Objective To investigate the effect of allicin on the development of atherosclerosis in apoE-/-mice and explore its underlying mechanism from the perspective of protein S-nitrosylation.Methods Thirty male apoE-/- mice were randomly divided into 3 groups:control group (saline,ig),low-dose group (allicin,9 mg/kg·d, ig)and high-dose group (allicin,18 mg/kg·d,ig).They were fed with high cholesterol diet for 12 weeks.The levels of plasma lipids,oxidized-LDL (ox-LDL),malondialdehyde,tumor necrosis factor-alpha and nitric oxide (NO)were measured.The atherosclerotic lesions in aortic root were evaluated after hematoxylin and eosin staining and elastica van Gieson and immunohistochemical staining,respectively.Furthermore,in vitro experiments were performed using human umbilical vein endothelial cells (HUVECs).The HUVECs were treated with allicin (10μmol/L or 20 μmol/L)for 24 hours in the presence of ox-LDL (50 μg/mL).The level of NO in supernatant was measured by a nitrate/nitrite assay. The protein S-nitrosylation of the HUVECs was detected through immunofluorescence.Results The histological analysis revealed that allicin treatment not only significantly decreased the areas of the atherosclerotic lesion (all P <0.05)but also suppressed the macrophage accumulation and smooth muscle cell proliferation in the lesion.There was no significant difference in the levels of plasma lipids between control and treated groups.However,allicin exerted obvious anti-oxidative and anti-inflammatory effects. Interestingly,the allicin treatment led to marked increase of the plasma NO level (P <0.05)and aortic protein S-nitrosylation.The experiments in vitro further proved that the allicin up-regulated the levels of NO and protein S-nitrosylation in HUVECs treated with ox-LDL (P < 0.01 ).Conclusion Allicin can inhibit the development of atherosclerosis.The mechanism is associated with the up-regulation of protein S-nitrosylation in endothelial cells, which plays an important role in anti-oxidization and anti-inflammation.
7.Study of α1 adrenoceptor-mediated vasoconstriction and protein expressions induced by mmLDL in mouse mesenteric artery
Lijun GUO ; Gaofeng JIANG ; Haipeng LI ; Qiong LI ; Enqi LIU ; Jie LI
Chinese Pharmacological Bulletin 2015;(6):827-832,833
Aim To investigate the effects of mmLDL on the up-regulation ofα1 receptors in moues mesenter-
ic arteries. Methods Mice tail intravenous injection of mmLDL was used . Vitro sensitive myograph was empl-
oyed to examine Noradrenaline ( NA) induced vascular contraction on mice mesenteric artery, and the mRNA and protein expressions ofα1 andα2 receptors were an-alyzed by real-time PCR and Western blot, respective-ly. Results mmLDL significantly increased NA in-duced concentration-contractile curve, and the data of Emax and pEC50 were from ( 122. 61 ± 9. 40 )% and (5. 65 ± 0. 05 ) in normal saline ( NS ) group to (161. 01 ± 6. 90 )% and ( 6. 20 ± 0. 08 ) in mmLDL group (P <0. 01, P <0. 01), respectively. The α1 adrenoceptor antagonist prazosin shifted the concentra-
tion-contractile curve induced by NA towards right. Af-ter using mmLDL, the mRNA and protein levels of α1 adrenoceptor were significantly increased, but the mR-NA and protein levels of α2 adrenoceptor were not changed. Conclusion Tail intravenous injection of mmLDL enhances the vascular expressions of α1 adre-noceptors and the contractile effects mediated byα1 ad-renoceptors.
8.Morphological characteristics and surgical strategy of complex hyperextension tibial plateau fracture
Zhongyu LIU ; Jinli ZHANG ; Peijia LIU ; Qijie SHEN ; Qing CAO ; Tao ZHANG ; Baocheng ZHAO ; Enqi LI ; Junchao ZHAO ; Yang CHEN
Chinese Journal of Orthopaedics 2021;41(5):289-296
Objective:To explore the morphological characteristics, treatment strategies and clinical results of complex hyperextension tibial plateau fractures.Methods:From October 2017 to January 2019, data of 27 patients with complex hyperextension tibial plateau fractures were retrospectively analyzed. There were 19 males and 8 females with an average age of 43.4 years (range, 23-68 years). According to Schatzker classification of tibial plateau fractures: there are 8 cases of type IV, 5 of type V, and 14 of type VI; according to the three-column theory classification: there are 8 cases of two-column fracture and 19 cases of three-column fracture. Bicondylar fractures were treated with medial Tomofix locking plate and anterolateral L-shaped locking plate through medial and anterolateral approach; tibialmedial condylar fractures was treated with T-shaped plate and posteromedial locking plate through extended medial approach. Patients with anterior tibial fractures were treated with horizontal strip plate through modified anterior median approach. Combined soft tissue or bone injury was repaired. The fracture healing and reduction were evaluated by X-ray and CT scan. The reduction of tibial plateau fracture was evaluated by Rasmussen radiology standard, and the knee joint function was evaluated 12 months after the operation by the score of American hospital for special surgery (HSS).Results:All the 27 surgeries were performedsuccessfully. The operation time was 130-350 minutes, with an average time of 165 minutes. Twenty-seven cases were followed up for 12-24 months, with an average period of 15.8 months. All fractures were healed. The average clinical healing time was 13.5 weeks (range, 10-18 weeks). Twelve months after operation, Rasmussen's radiology score was 13-18, with an average of 16.7 points, among them there were 19 excellent and 8 good. Twelve months after the operation, the score of HSS knee joint was 82-98, with an average score of 93.2 points, and there were 22 cases excellent, 4 cases good and 1 case fair. The excellent and good rate was 96.2% (26/27).Conclusion:Complex hyperextension tibial plateau fractures often combined with tibial bicondylar, medial tibial condyle or anterior tibial fractures. According to the morphological characteristics of complex hyperextension tibial plateau fractures, using appropriate surgical approach and internal fixation, repairing ligament soft tissue structure and reconstructing knee joint stability can achieve satisfactory results.
9.Effects of extremely low frequency electromagnetic field and its combination with lead on the antioxidant system in mouse.
Yun LIU ; Enqi WENG ; Ying ZHANG ; Rong HONG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2002;20(4):263-265
OBJECTIVETo study the effects of extremely low frequency electromagnetic field(ELF EMF) and its combination with lead on the antioxidant system in mouse brain and liver tissues.
METHODMice were exposed to a 50 Hz sinusoidal 0.2 mT or 6.0 mT EMF for 2 weeks. At the same time, some groups were exposed to lead(50 mg/kg). After the exposure, the antioxidant system and cell membrane fluidity in brain and liver were measured.
RESULTSMalondiadehyde(MDA) content in brain and liver increased from the control levels of (1.33 +/- 0.12) and (3.95 +/- 0.21) nmol/mg pro to (1.35 +/- 0.09) and (6.15 +/- 0.28) nmol/mg pro respectively following 0.2 mT exposure, and to (3.98 +/- 0.10) and (6.50 +/- 0.79) nmol/mg pro respectively following 6.0 mT exposure. Total antioxidant capability(T-AOC) in brain and liver decreased from the control levels of (4.39 +/- 0.48) and (2.45 +/- 0.21) U/mg pro to (3.99 +/- 0.39) and (1.92 +/- 0.32) U/mg pro respectively following 0.2 mT, and to (3.12 +/- 0.37) and (1.57 +/- 0.14) U/mg pro respectively following 6.0 mT. GSH content decreased only in liver tissue from the control level of (194.60 +/- 20.93) mg/g pro to (189.24 +/- 5.61) mg/g pro(0.2 mT) and (153.04 +/- 1.18) mg/g pro(6.0 mT). Cellular membrane fluidity decreased from the control levels of (1.396 +/- 0.040) and (2.899 +/- 0.552) to (1.224 +/- 0.190) and (1.894 +/- 0.0761) (0.2 mT), (1.159 +/- 0.179) and (1.516 +/- 0.204)(6.0 mT) respectively. Compared with single EMF exposure(6.0 mT), EMF combined with lead exposure induced remarkable increase in MDA, GSH content and T-AOC and decrease in cell membrane fluidity both in the brain and liver, and increase in SOD activity only in liver.
CONCLUSIONELF EMF might alter the metabolism of free radicals, decrease anti-oxidant capability and enhance lipid peroxidation. The combination of EMF with lead showed synergic effects on lipid peroxidation.
Animals ; Antioxidants ; metabolism ; Brain ; drug effects ; metabolism ; radiation effects ; Electromagnetic Fields ; adverse effects ; Glutathione ; analysis ; Lead ; toxicity ; Lipid Peroxidation ; drug effects ; radiation effects ; Liver ; drug effects ; metabolism ; radiation effects ; Membrane Fluidity ; drug effects ; radiation effects ; Mice ; Superoxide Dismutase ; metabolism
10.Establishment of posterior tibial plateau partition and its clinical significance for surgical approach selection
Zhaojie LIU ; Jinli ZHANG ; Zhongyu LIU ; Enqi LI ; Qijie SHEN ; Qing CAO ; Baocheng ZHAO
Chinese Journal of Orthopaedics 2018;38(13):805-812
Objective To explore the guiding significance of posterior tibial plateau partition for the selection of surgical approach in treatment for posterior column fracture.Methods From June 2008 to May 2015,46 patients with posterior column fractures of tibial plateaus treated were retrospectively analyzed.There were 31 males and 15 females with an average age of 35.1±12.8 years old (range,19-62 years).Nineteen patients were left side and twenty-seven patients were right side.Injury was caused by traffic accident in 27 cases,falling from bicycle in 12 cases and falling from height in 7 cases.On the basis of the posterior condyle with anatomical structure in tibia1 plateau,the posterior column was divided into four parts.All fractures were treated via the optimal approach based on the location of them.The posteromedial approach was used with fractures in zone 1 and 2,posterolateral approach used in zone 3,lateral approach via the fibular head osteotomy was used in zone 4 and combined approaches were used in multiple zones.All the fractures involved the posterior column were treated by anatomical reduction and fixation with plates and screws under direct vision.Results All the patients were followed up with an average of 15.5±3.7 months (range from 12 to 24 months).The healing time of all patients was 11-18 weeks,with an average time of 14.6±2.3 weeks.According to Rasmussen radiographic evaluation,the average score was 15.1 (range from 11 to 18) and clinical outcomes were rated with "excellent" in 17 cases,"good" in 24 cases,"fair" in 5 cases.The excellent and good rate was 89.1% (41/46).The mean HSS (the Hospital for Special Surgery) score of all patients at 12 months operatively were 86.7±8.6 (range from 67 to 98) and the functional scores were excellent in 25 cases,good in 17 cases and fair in 4 cases with the excellent and good rate was 91.3% (42/46).The average range of motion in affected knee was 118°±13.7° (range from 0° to 135°) in 17 cases via posterolateral approach,123°±15.6° (range from 0° to 135°) in 18 cases via posteromedial approach,115°±16.7° (range from 0° to 130°) in 18 cases via combined posteromedial and posterolateral approaches and 124°±7.4° (range from 0° to 130°) in 4 cases via the fibular head osteotomy lateral approach.Complications included fat liquefaction in 1 case,anterior tibial artery spasm in 1 case and traumatic arthritis in 1 case.Conclusion The partition of posterior tibial plateau can be used to guide the surgical approach to the posterior column simply and accurately.For the fractures of isolated posterior column and posterior column mainly involved,the partition has a certain guiding significance.