摘要:目的:探討卡配因抑制劑3(MDL28170)對新生大鼠缺氧缺血性腦損傷(HIBD)神經細胞凋亡的影響。方法:建立新生SD大鼠HIBD模型,治療組于缺養缺血后即刻、2 h、4 h腹腔內注射MDL28170,對照組及手術組同時予生理鹽水。缺氧缺血后24 h用免疫組化方法觀察大腦皮質及海馬CA1區Caspase3 蛋白表達、TUNEL法檢測細胞凋亡,觀察組織病理改變并計算海馬神經元死亡數,透射電鏡觀察細胞超微結構。結果:缺氧缺血后24 h缺血側大腦皮質及海馬CA1區Caspase3和TUNEL陽性細胞數較對照組明顯增加,透射電鏡證實有凋亡細胞;MDL28170可減少陽性細胞數量,抑制神經元死亡,差異有顯著性(Plt;0.05)。結論:MDL28170可通過抑制神經凋亡而對新生大鼠HIBD具有一定保護作用。Abstract: Objective: To investigate the effect of (Calpain inhibitor3) MDL28170 on neural apoptosis in a neonatal model of hypoxicischemic brain damage (HIBD). Methods: A neonatal model of HIBD was established, 7dayold SD rats were divided into three groups. The treatment group received MDL28170(ip) at 0 h,2 h,4 h after HI, whereas the other two groups were administered normal saline simultaneously. The expression of caspase3 (by immunohistochemistry), neural apoptosis (by TUNEL) in cortex and hippocampus ipsilateral to the insult were observed 24 h after HI; hippocampal CA1 neural loss and electromicroscopic changes were assessed at the same time. Results: Apoptotic body was observed by electromicroscopy. Caspase3 positive cells and apoptotic cells increased significantly in the ipsilateral cortex and hippocampal CA1 region compared to the control, and MDL28170 reduced the number of positive cells, attenuated CA1 neural loss with significance (Plt;0.05). Conclusion: It is suggested that MDL28170 may protect the brain of neonatal rats after HIBD by suppressing neural apoptosis.
To investigate the function of nitric oxide (NO) and nitric oxide synthetase (NOS) inhibitor, N-nitro-L-arginine methyl ester (L-NAME), the skin avulsion model was made in the lower extremity of pig. The methods of measurement of size of the survived flap, weighing, immunocytochemistry and hybridization in situ were employed, so that the survival surface area of flaps, tissue wet/dry weight ratio, NO content in the serum, gene expression of NO and NOS content in the flap tissue were determined, respectively. The results showed that the early gene expression of NOS was increased as well as the NO content and tissue wet/dry weight ratio (P lt; 0.01). After L-NAME was applied introvenously, the NO content and tissue wet/dry weight ratio were decreased (P lt; 0.01), and the survival surface area of flaps was enlarged (P lt; 0.01). It could be concluded that the NO might play a role in the development of the pathological changes as early congestion, edema and secondary necrosis in the avulsed skin flaps. The early application of L-NAME could do some good to the avulsed skin flap and protect it from further necrosis owing to the presence of NO.
【Abstract】 Objective To reduce restenosis in vein grafts after coronary artery bypass grafting, to investigate theeffect of human tissue factor pathway inhibitor(TFPI) gene del ivery on neointima formation. Methods The eukaryotic expressed plasmid vector pCMV-(Kozak) TFPI was constructed. Forty-eight Japanese white rabbits were randomly divided into 3 groups with 16 rabbits in each group: TFPI group, empty plasmid control group and empty control group. Animal model of common carotid artery bypass grafting was constructed. Before anastomosis, vein endothel iocytes were transfected with cationic l iposome containing the plasmid pCMV- (Kozak) TFPI (400 μg) by pressurizing infusion (30 min) in TFPI group. In empty plasmid control group, vector pCMV- (Kozak) TFPI was replaced by empty plasmid pCMV (400 μg). In empty control group, those endothel iocytes were not interfered. After operation, vein grafts were harvested at 3 days for immunohistochemical, RTPCR and Western-blot analyses of exogenous gene expression and at 30 days for histopathology measurement of intimal areas, media areas and calculation of intimal/media areas ratio. Luminal diameter and vessel wall thickness were also measured byvessel Doppler ultrasonography and cellular category of neointima was analyzed by transmission electron microscope at 30 days after operation. Results Human TFPI mRNA and protein were detected in TFPI group. The mean luminal diameter of the TFPI group, empty plasmid control group and empty control group was (2.68 ± 0.32) mm, (2.41 ± 0.23) mm and (2.38 ± 0.21) mm respectively. There were statistically significant differences between TFPI group and control groups (P lt; 0.05). The vessel wall thickness of the TFPI group, empty plasmid control group and empty control group was (1.09 ± 0.11) mm, (1.28 ± 0.16) mm and (1.34 ± 0.14) mm respectively. There were statistically significant differences between TFPI group and other control groups (P lt; 0.01). The mean intimal areas, the ratio of the intimal/media areas of the TFPI group were (0.62 ± 0.05) mm2and 0.51 ± 0.08 respectively, which were reduced compared with those of the two control groups(P lt; 0.05). The mean media areas had no significant differences among three groups (P gt; 0.05). Through transmission electron microscope analyses, no smoothmuscle cells were seen in neointima of TFPI group in many visual fields, but smooth muscle cells were found in neointima of two control groups. Conclusion Human TFPI gene transfection reduced intimal thickness in vein grafts.
Objective To explore the effects of overexpression of human tissue inhibitors of metalloproteinase-1 (hTIMP-1) on proliferation of human liver cancer cell line HepG2 in vitro. Methods A recombinant adenoviral vector containing full-length cDNA of hTIMP-1 was generated and transfected into HepG2. The viral titer was checked by measuring GFP, and the expression of hTIMP-1 in vitro was detected by the techniques of Western blot and semi-quantitative RT-PCR. The ultrastructure was observed by transmission electron microscope and the effects of overexpression of hTIMP-1 on proliferation of HepG2 in vitro was analyzed by MTT assay and growth curve. Results The resultant AdhTIMP-1 was successfully constructed and the expression of hTIMP-1 was detected by Western blot and RT-PCR. The growth and proliferation of HepG2, which had been transfected with AdhTIMP-1, was significantly inhibited. Conclusion The proliferation of HepG2 was markedly inhibited by recombinant adenovirus-mediated overexpression of hTIMP-1, which may pave the way for further application in liver gene therapy.
Objective To review researches of the role of inhibitorof differentiation 2(Id2) in skeletal muscle regeneration. Methods The latest original literature concerning Id2 and its role in skeletal muscle regeneration was extensively reviewed. Results Id2 could form heterodimers by combining with E protein to prevent myogenic regulatory factors (MRFs) forming heterodimers by combining with E protein, to inhibit the transcription activity of MRFs anddifferentiation of skeletal muscle cell. Conclusion Id2 plays an important role in skeletal muscle regeneration.
Objective To study the effect of the competitive inhibitor of nitric oxide synthase NG-nitro-L-arginine methyl ester (LNAME) on thedenervated muscle atrophy. Methods A model of the denervated gastrocnemius atthe right lower limb was established in 36 SD adult rats. The rats were randomly divided into two groups: the L-NAMEgroup (Group A) and the control group(Group B). L-NAME 10 mg/ kg daily was injected into the denervated gastrocnemius inGroup A, and normal saline was injected into the denervated gastrocnemius in Group B. At 2, 4 and 8 weeks after operation, the rate of the muscle wet weight preservation, the cross section area of the myocyte, the protein amount, and the percentage of the apoptotic muscle cells were measured respectively and the ultramicrostructure of the myocyte was observed. Results At 2 and 4 weeks after operation, the rate of the muscle wet weight preservation, the cross section area of themyocyte, and the protein amount were significantly greater in Group A than in Group B; however, the percentage of the apoptotic muscle cells was significantly smaller in Group A than in Group B. The observation of the ultramicrostructure of themyocyte showed that an injection of L-NAME could protect the ultramicrostructure of themyocyte. At 8 weeks after operation, there was no significant difference between the two groups in the abovementioned parameters. Conclusion The nitric oxide synthase inhibition can delay the denervated muscle atrophy.
Objective To review the recent studies on the suppressing function of breast cancer metastasis suppressor 1 (BRMS1) in breast cancer metastasis. Methods The recent literatures on the mechanisms of BRMS1 in the breast cancer that were published in and abroad were reviewed and summarized. Results BRMS1, similar to the other anti-metastasis genes, only suppresses the metastasis of breast cancer cells but has nothing to do with the growth of tumor. BRMS1 could suppress metastasis of tumor cells by reestablishing both the homospecific and the heterospecific gap junctional intercellular comminications (GJIC) and by altering the expressions of relevant metastasis genes in the breast cancer. Conclusion Further studies on BRMS1 may be helpful to understand the metastasis of breast cancer, which may provide a new way for the diagnosis and treatment of breast cancer.