1.Formalin-induced Nociceptive Behavior and c-fos Expression of Interbrain Following Stellate Ganglionic Block
Yong XIANG ; Juying LIU ; Chengming QING
Journal of Chinese Physician 2001;0(03):-
Objective To investigate formalin-induced nociceptive behavior and c-fos expression of interbrain following stellate ganglionic block (SGB) in rabbits. Methods Catheters were inserted closely to right stellate ganglia in rabbits by operation.One week later,twenty-four rabbits were randomly divided into three groups, each group containing 8 animals. groups A,B and C received 0.5ml of normal saline,3% formalin and 3% formalin stimulation by intraplantar injection , respectively. 10 minutes before stimulation,0.5 ml of 0.25% bupivacaine was administered via the catheter in group B, while in groups A and C 0.5 ml of normal saline was applied. Nociceptive behavior was observed for 1 hour using weighted pain score. 2 hours after stimulation, whole interbrain was removed to immunohistochemically detect the expression of c-fos. Results Formalin-induced nociceptive behavior in phase 2 was relieved following SGB, c-fos expression level of hypothalamus in group B was significantly lower than that in group C(P0.05). Conclusion SGB could relieve formalin-induced nociceptive behavior, and downregulate formalin-induced c-fos expression of hypothalamus, which may be related to the mechanisms of SGB for the treatment of inflammatory pain.
2.Influence of ketamine on astrocyte damage in spinal dorsal horn of rats induced by N-methyl-D-aspartic acid
Qing LI ; Juying LIU ; Qingshan ZHOU ; Tao ZHU ; Chengming QIN
Chinese Journal of Tissue Engineering Research 2006;10(32):187-189,封三
BACKGROUND: Ketamine is a kind of frequently used general venous anesthesia drug in clinic, and the medication in vein or epidural cavum has analgesic effect. It is N-methyl-D-aspartic acid (NMDA) receptor noncompetitive antagonist, which can inhibit toxic effect of excitatory amino acids.OBJECTIVE: To observe effect of ketamine on apoptosis of dorsal horn astrocytes of spinal cord of rats induced by NMDA receptor over activation and explore its possible mechanism of action.DESIGN: Randomized controlled observation.SETTING: Department of Anesthesiology, Taihe Hospital Affiliated to Yunyang Medical College.MATERIALS: The experiment was conducted at Cell Biology Laboratory,Institute of Basic Medical Sciences, Yunyang Medical College between September 2003 and January 2005. Neonatal Wistar rats of two or three days were provided by Animal Experimental Center of Wuhan University. METHODS: Primary astrocytes in dorsal horn of T11-L6 spinal cord of Wistar rats were purified and cultured. Astrocytes were used in the experiment when its purity coefficient reached 98% assessed by gial fibrillary acidic protein. The cultured cells in 24-well plates were divided randomly into 6 groups (9 portions in each group): ①50 μL Hanks liquor was added into the control group. ②Amount of 100μmol/L was added into the NMDA group. ③Amount of 1 mmol/L was added into the ketamine group. ④100μmol/L NMDA + 0.1 mmol/L ketamine group. ⑤100 μmol/L NMDA + 0.5 mmol/L ketamine group. ⑥100μmol/L NMDA + 1 mmol/L ke tamine group. 1 mmol/L ketamine was clinical antalgic dosage. Activity of superoxide dismutase (SOD) and content of malondialdehyde (MDA) were examined after 24-hour culture. Content of Bcl-2 protein and change of morphology were observed with immunocytochemistry. Apoptosis of astrocytes was measured with flow cytometry. MAIN OUTCOME MEASURES: ① Counterstain cell staining and changes of morphology of Bcl-2 protein with immunohistochemical method and hematoxylin-esoin staining (HE). ②Apoptosis of astrocytes was detected with flow cytometry. ③Content of MDA and activity of SOD.RESULTS: ①Mean absorbance (A) of Bcl-2 as expression of Bcl-2 protein measured semiquantitatively: It was lower in the 100μmoL/L NMDA group than the control group, which had significant difference [0.054±0.021,0.108±0.039, respectively, P<0.01]. It was higher in the 100 μmol/L NMDA + 1 mmol/L ketamine group than the 100 μmol/L NMDA group,which had significant difference [0.148±0.045, 0.054±0.021, respectively,P < 0.01]. ②Apoptosis of astrocytes detected with flow cytometry: It was higher in the 100μmol/L NMDA group than the control group, which had significant difference [(25.26±6.13)%, (5.66±2.24)%, respectively, P<0.01].It was lower in the 100μmol/L NMDA + 1 mmol/L ketamine group than in the 100μmol/L NMDA group, which had significant difference[(24.41±4.82)%, (25.26±6.13)%, respectively, P<0.01]. ③Content of MDA and activity of SOD: 100 μmol/L NMDA made the content of MDA in astrocytes obviously increase , while the activity of SOD markedly decrease. 1 mmol/L ketamine remarkably decreased the content of MDA, distinctly increased the activity of SOD. This effectiveness had evidently dosage-effect relationship in clinical antalgic dosage, which had obviously difference as compared with that of the NMDA group (P < 0.01 ). The differences between the 1 mmol/L ketamine group and the control group as well as between the 100 μmol/L NMDA + 0.1 mmol/L ketamine group and the NMDA group had insignificant difference.CONCLUSION: NMDA receptor over activation can induce apoptosis of a great number of astrocytes in spinal dorsal horn of rats. Suitable ketamine dramatically inhibits apoptosis, and its mechanism can enhance the expressionof Bcl-2 protein of astrocytes, at the same time inhibit the production of free radical and reinforce the activity of SOD.
3.Magnesium lithospermate B enhances the potential of human-induced pluripotent stem cell-derived cardiomyocytes for myocardial repair
Chengming FAN ; Kele QIN ; Daniel Chukwuemeka IROEGBU ; Kun XIANG ; Yibo GONG ; Qing GUAN ; Wenxiang WANG ; Jun PENG ; Jianjun GUO ; Xun WU ; Jinfu YANG
Chinese Medical Journal 2024;137(15):1857-1869
Background::We previously reported that activation of the cell cycle in human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) enhances their remuscularization capacity after human cardiac muscle patch transplantation in infarcted mouse hearts. Herein, we sought to identify the effect of magnesium lithospermate B (MLB) on hiPSC-CMs during myocardial repair using a myocardial infarction (MI) mouse model.Methods::In C57BL/6 mice, MI was surgically induced by ligating the left anterior descending coronary artery. The mice were randomly divided into five groups ( n = 10 per group); a MI group (treated with phosphate-buffered saline only), a hiPSC-CMs group, a MLB group, a hiPSC-CMs + MLB group, and a Sham operation group. Cardiac function and MLB therapeutic efficacy were evaluated by echocardiography and histochemical staining 4 weeks after surgery. To identify the associated mechanism, nuclear factor (NF)-κB p65 and intercellular cell adhesion molecule-1 (ICAM1) signals, cell adhesion ability, generation of reactive oxygen species, and rates of apoptosis were detected in human umbilical vein endothelial cells (HUVECs) and hiPSC-CMs. Results::After 4 weeks of transplantation, the number of cells that engrafted in the hiPSC-CMs + MLB group was about five times higher than those in the hiPSC-CMs group. Additionally, MLB treatment significantly reduced tohoku hospital pediatrics-1 (THP-1) cell adhesion, ICAM1 expression, NF-κB nuclear translocation, reactive oxygen species production, NF-κB p65 phosphorylation, and cell apoptosis in HUVECs cultured under hypoxia. Similarly, treatment with MLB significantly inhibited the apoptosis of hiPSC-CMs via enhancing signal transducer and activator of transcription 3 (STAT3) phosphorylation and B-cell lymphoma-2 (BCL2) expression, promoting STAT3 nuclear translocation, and downregulating BCL2-Associated X, dual specificity phosphatase 2 (DUSP2), and cleaved-caspase-3 expression under hypoxia. Furthermore, MLB significantly suppressed the production of malondialdehyde and lactate dehydrogenase and the reduction in glutathione content induced by hypoxia in both HUVECs and hiPSC-CMs in vitro. Conclusions::MLB significantly enhanced the potential of hiPSC-CMs in repairing injured myocardium by improving endothelial cell function via the NF-κB/ICAM1 pathway and inhibiting hiPSC-CMs apoptosis via the DUSP2/STAT3 pathway.