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Glioblastoma multiforme (GBM) is the most aggressive grade IV astrocytoma which is the common type of malignant (cancerous) primary brain tumor.The median survival time was 15-17 months.At present, the conventional treatment methods of GBM are surgical resection, radiotherapy and temozolomide chemotherapy of Temozolomide.The invasiveness of tumor is not only the main obstacle of surgery, radiotherapy and chemotherapy, but also the main cause of death of GBM patients.GBM patients will gradually develop resistance to chemotherapy, leading to tumor regrowth or recurrence, but the exact mechanism is not very clear.In recent years, the role of hypoxia in tumor metastasis and invasion has been paid more and more attention.Understanding how hypoxia induces GBM cell invasiveness is particularly important for developing new and more effective therapies to combat this catastrophic disease.It is believed that hypoxia can increase the invasiveness of GBM by inducing degradation and remodeling of extracellular matrix, expression of tissue factors, promoting epithelial mesenchymal transition and angiogenesis, and regulating GBM ion channels.
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Objective:To investigate the influence of α cells and glucagon-like peptide l (GLP-1) in the function of β cells (INS-1 cells) in the rats,and to elucidate the possible mechanism of α cells and INS-1 cells transplantation in influencing hypoglycemia.Methods:The proliferation abilities of INS-1 cells after treated with 10％,20％ and 30％ islet α-cell conditioned medium and 0.03,0.30,3.00,30.0 mg · L-1 of GLP-1 were analyzed by MTT assay.The levels of insulin secretion of INS-1 cells after treated with 10％,20％,30％ α cells,α-cell conditioned medium and different concentrations of GLP-1 were analyzed by enzyme linked immunosorbent assay (ELISA).The concentrations of Ca2+ in INS-1 cells after treated with high glucose and GLP-1 were analyzed by laser confocal microscope.The expression levels of insulin protein after treated with different concentrations of islet α-cell conditioned medium and different concentrations of GLP-1 were detected by Western blotting methed.After the INS-1 cells,the mixture of INS-1 cells and α cells were transplanted into the left renal capsule of the nude mice,the blood glucose levels and the kidney morphology were observed.The levels of insulin/glucagon in the transplanted cells were detected by immunohistochemistry.Results:Compared with control group,both of α-cell conditioned media and GLP-1 promoted the INS-1 cell proliferation and insulin secretion (P ＜ 0.05).The laser confocal microscope results revealed that GLP-1 stimulated the increased intracellular Ca2+ concentration in INS-1 cells (P＜ 0.05).Compared with control group,there was no significant difference in the expression levels of insulin protein in the insulin-1 cells after treated with islet α cell conditioned medium and GLP-1 (P＞0.05).Compared with pre transplantation,the blood glucose level in the transplanted INS-1 cells was significantly decreased at 35 d after renal capsul trasplantation (P＜0.05),and even hypoglycemia presented renal capsular in the diabetic nude mice;the transplantation site was obviously swollen.However,the levels of blood glucose had no change of the diabetic rats after transplated with the mixture of INS-1 and α cells (P＜0.05).The expression of insulin and glucagon in the INS-1 transplanted cells were found by immunohistochemistry staining.Conclusion:Pancreatic islet α cells and their secretions can promote the INS-1 cell proliferation and insulin secretion,and the mixture of INS-1 cells and α cells transplanted under the renal capsule of the diabetic nude mice can reduce the hypoglycemic effect of INS-1 cell transplantation which might be related to the INS-1 cells that can express both of insulin and glucagon genes.
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Objective:To investigate the influence of α cells and glucagon-like peptide l (GLP-1) in the function of β cells (INS-1 cells) in the rats,and to elucidate the possible mechanism of α cells and INS-1 cells transplantation in influencing hypoglycemia.Methods:The proliferation abilities of INS-1 cells after treated with 10％,20％ and 30％ islet α-cell conditioned medium and 0.03,0.30,3.00,30.0 mg · L-1 of GLP-1 were analyzed by MTT assay.The levels of insulin secretion of INS-1 cells after treated with 10％,20％,30％ α cells,α-cell conditioned medium and different concentrations of GLP-1 were analyzed by enzyme linked immunosorbent assay (ELISA).The concentrations of Ca2+ in INS-1 cells after treated with high glucose and GLP-1 were analyzed by laser confocal microscope.The expression levels of insulin protein after treated with different concentrations of islet α-cell conditioned medium and different concentrations of GLP-1 were detected by Western blotting methed.After the INS-1 cells,the mixture of INS-1 cells and α cells were transplanted into the left renal capsule of the nude mice,the blood glucose levels and the kidney morphology were observed.The levels of insulin/glucagon in the transplanted cells were detected by immunohistochemistry.Results:Compared with control group,both of α-cell conditioned media and GLP-1 promoted the INS-1 cell proliferation and insulin secretion (P ＜ 0.05).The laser confocal microscope results revealed that GLP-1 stimulated the increased intracellular Ca2+ concentration in INS-1 cells (P＜ 0.05).Compared with control group,there was no significant difference in the expression levels of insulin protein in the insulin-1 cells after treated with islet α cell conditioned medium and GLP-1 (P＞0.05).Compared with pre transplantation,the blood glucose level in the transplanted INS-1 cells was significantly decreased at 35 d after renal capsul trasplantation (P＜0.05),and even hypoglycemia presented renal capsular in the diabetic nude mice;the transplantation site was obviously swollen.However,the levels of blood glucose had no change of the diabetic rats after transplated with the mixture of INS-1 and α cells (P＜0.05).The expression of insulin and glucagon in the INS-1 transplanted cells were found by immunohistochemistry staining.Conclusion:Pancreatic islet α cells and their secretions can promote the INS-1 cell proliferation and insulin secretion,and the mixture of INS-1 cells and α cells transplanted under the renal capsule of the diabetic nude mice can reduce the hypoglycemic effect of INS-1 cell transplantation which might be related to the INS-1 cells that can express both of insulin and glucagon genes.
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Objective:To observe the inhibitory effect of ischemic postconditioning (I-postC) on the apoptosis of renal cells after limb ischemia reperfusion(LIR) in the rats, and to investigate the possible mechanisms. Methods:Thirty SD rats were randomly divided control group, ischemia-reperfusion group(IR group) and I-postC group(n=10).4 h ischemia and 4 h reperfusion with the rubber band in two hind limbs of the rats were performed to establish the models.In control group, the rubber band around the limb was loose and the blood flow was not blocked.As for I-postC group, before perfusion, 5 min ischemia and 5 min reperfusion were performed in the rats and repeated 3 times named I-post C.The levels of blood creatinine (Cr), blood urea nitrogen(BUN) and C-reactive protein (CRP) in plasma of the rats in various groups were measured by automatic biochemistry analyzer.The expressions of Bcl-2 protein and Bax protein in renal were detected by immunohistochemical method,and its quantitative results were observed with automatic image analysis system and the ratio of Bcl-2/Bax was calculated.The apoptotic cells in kidney tissue were determined by terminal-deoxynucleotidy1 transferase-mediated d-UTP nick end labeling (TUNEL) under laser scanning confocal microscope(LSCM).The ultrastructures of kidney tissue were observed under electron microscope.Results:Compared with control group, the levels of Cr,BUN and CRP in plasma of the rats in IR group and I-postC group were increased(P<0.05 or P<0.01);compared with IR group, the levels of Cr, BUN and CRP in plasma of the rats in I-postC group were decreased(P<0.01).Compared with control group,the expression levels Bax and Bcl-2 in kidney tissue of the rats in IR group and I-postC group were significantly increased (P<0.05 or P<0.01),and the ratios of Bcl-2/Bax were reduced(P<0.05);compared with IR group,the expression level of Bax in kidney tissue of the rats in I-postC group was decreased (P<0.05),the expression level of Bcl-2 was increased(P<0.01),and the ratio of Bcl-2/Bax was increased(P<0.05).Under laser confocal microscope,the number of apoptotic cells in kidney tissue of the rats in IR group was increased compared with control group;the number of apoptotic cells in I-postC group was decreased compared with IR group.Under transmission electron microscope,the changes in IR group were found as follows: renal proximal convoluted tubule epithelial cell nucleus vacuoles,increased lysosome and dense particle deposition, some mitochondria crest fracture or fuzzy;irregular and fusion, glomerular podocyte protuberance,mitochondrial cristae fracture and reducetion with vacuoles, rough endoplasmic reticulum expansion;the damage levels of renal tubular epithelial cells and glomerulus in I-postC group were improved compared with IR group.Conclusion: Limb ischemia reperfusion can induce the apoptosis of renal cells, I-postC can inhibit the apoptosis of renal cells,and it would be helpful to improve the kidney function.
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Objective To observe the effects of ischemic postconditioning (I-postC) on lung injury after limb ischemia reperfusion (LIR) in rats, and to investigate the protective effect and the mechanisms. Methods Twenty-four Wistar rats were divided into three groups:control group (group Control), ischemia-reperfusion group (group IR) and ischemic postcondi?tioning group (group I-postC). Referring to routine method in our department, the model rats underwent 4-hour ischemia and 4-hour reperfusion of hind limbs were made. In group Control, the rubber band around the limb was loose,which did not block the blood flow. Rats in group I-postC were given repeated 3 times of 5 min ischemia-5 min reperfusion, and then did perfusion 4 h before reperfusion. The blood and lung samples were collected for detecting arterial gas of partial pressure of oxygen [p(O2)] and partial pressure of carbon dioxide [p(CO2)]. The plasma and lung tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD) and xanthine oxidase (XOD) were detected. The morphological changes of lung tissue were ob?served under light microscope and electron microscope. Results It was found that after suffering from ischemia-reperfu?sion, levels of p(O2) and p(CO2) decreased significantly. The activity of SOD in plasma and lung tissues decreased, but XOD and MDA increased significantly (P<0.05). With microscope, lung interstitial vascular dilation, infiltration of neutrophils, the width of the alveolar space, alveolar septal thickening and alveolar exudate were found. Compared with IR group, it was found that p(O2) and p(CO2) increased significantly in group I-postC. The activity of SOD in plasma and lung tissues in?creased, but XOD and MDA decreased significantly(P<0.05). The mild damage of pathological changes were found. Conclu?sion Ischemic postconditioning can reduce the lung injury after limb ischemia reperfusion in rats, which may be related to the inhibition of lipid peroxidation.
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Objective:To observe the effects of ischemic postconditioning (I-postC)on the lung injury after limb ischemia reperfusion (LIR)in the rats,and to investigate the protective effect and the possible mechanisms. Methods:24 Wistar rats were randomly divided into control group, ischemia-reperfusion group (IR group)and I-postC group (n=8 ). Referring to routine method in our department, the model rats which underwent 4 h ischemia and 4 h reperfusion of hind limbs were made.In control group,the rubber band around the limb was loose and the blood flow was not blocked. In I-postC group, before reperfusion, ischemia 5 min and reperfusion 5 min were performed in the rats,repeated for 3 times and then perfusion 4 h was taken,The blood and lung tissue from every rat were taken accurately. The percentages of CD1 8 positive cells in peripheral blood,the levels of soluble intercellular adhesion molecule-1 (sICAM-1)and P-selectin in plasma,the myeloperoxidase (MPO)activities in lung tissue,the levels of intercellular adhesion molecule-1 (ICAM-1)and P-selectin in lung tissue of the rats in various groups were detected. The partial pressure of oxygen (PaO2 ) and partial pressure of carbon dioxide (PaCO2 )were measured.The morphological changes of lung tissue under light and electron microscopes were observed.Results:Compared with control group,the percentage of CD18 positive cells and the levels of sICAM-1 and P-selectin of the rats in IR groups were increased (P<0.01);PaO2 and PaCO2 were decreased significantly;the MPO activity in lung tissue was also significantly increased (P<0.01).The HE staining results showed lung interstitial vascular dilation, congestion, PMN infiltration, the increased gap blood vessel, alveolar septal thickening,alveolar exudation, bronchial epithelial cell shedding and necrosis of the rats in IR group. Compared with IR group,the values of biochemical indicators mentioned above were decreased obviously (P<0.01);PaO2 and PaCO2 were increased significantly (P<0.01);the activities of inflammatory factors in plasma and lung tissue were decreased (P < 0.01 ); the pathological changes of lung damage were improved significantly. Conclusion:I-postC can reduce the lung injury after LIR in the rats,and the mechanism may be related to inhibiting the inflammatory reaction.
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Objective To investigate the protective effects of rhein lysinate ( RHL) on cardiac tissue damage in-duced by paraquat in experimental mice , and to clarify its mechanism .Methods In this study mice were assigned to the following three groups: control, paraquat model, and RHL-treated groups.The model of oxidative damage mice was established by intraperitoneal injection of paraquat .RHL-treated group was given RHL ( 50 mg/kg ) by gavage for one week before performing model .The other two groups were given equal volume of distilled water .For making model , paraquat was intraperitoneally injected in the paraquat model and RHL-treated group .The content of MDA was detected by thiobarbituric acid assay .The activities of SOD and GSH-Px were detected by biphenyl three phenolic autoxidation assay and NADPH coupling method respectivly .The pathological profile of cardiac tis-sue was observed by hematoxylin and eosin ( HE) staining and reactive oxygen species was observed by DCFH-DA staining .The change of proteins related to myocardial damage detected by Western blot .Results Compared with control group, the activities of SOD and GSH-Px decreased (P<0.05) and the content of MDA increased (P<0.05) in paraquat model group .However , these changes were attenuated byr RHL treatmen ( P<0.05 ) .The pathologi-cal examination indicated the structure of cardiac tissue was damaged and reactive oxygen species of cardiac tissue was increased after paraquat was given , however , these changes were attenuated after RHL treatmen .It was shown in western blot analysis that compared with control group , the expression of SIRT1 decreased, the acetylation of P53 and the expression of P 53 and P66 increased in paraquat-treated group .These changes were attenuated by RHL treatmen ( P<0.05 ) .Conclusions RHL may attenuate paraquat-induced cardiac injury in mice .