Objective To summarize the advance of bioenergetic metabolic mechanisms of cancer cell. Methods Literatures about the recent studies on the bioenergetic metabolic mechanisms of cancer cell were reviewed.Results Cancer cells required a steady source of metabolic energy in order to continue their uncontrolled growth and proliferation. Accelerated uptake of glucose and glycolysis was one of the biochemical characteristics of hypoxia cancer cells. Glucose transport and metabolism were essential for the survival of tumor cells, leading to poor prognosis. Conclusions The studies on relationships between hypoxia-inducible genes and cancer have come a new understanding of the bioenergetic metabolic mechanisms of cancer cell, become new and important supplementary means of diagnosis and treatment of cancer, and enhanced existing strategies so that the treatment could be more rationally applied and personalized for cancer patients.
Objective To elucidate whether glucose transporters-4 （GLUT-4） takes part in glucose uptake of mesenchymal stem cells （MSCs） and whether Akt gene improves translocation and expression of GLUT-4 in MSCs under hypoxic environment ex vivo. Methods MSCs, transfected by Akt gene and no, were cultured with normoxia (5% CO2) or hypoxia (94%N2, 1%O2 and 5% CO2) at 37 ℃ for 8 h. Glucose uptake was assayed by using radiation isotope 2-［3H］-deoxy-Dglucose (3H-G) and the expression of GLUT-4 protein and mRNA was assayed by immunocytochemistry, Western blot and RT-PCR, respectively. Results ①3 H-G intake of MSCs was significantly increased in hypoxiatransfection group than that in hypoxia-non-transfection 〔（1.39±0.13） fold, P＜0.05〕, but which was lower than that in normoxia-non-transfection group, P＜0.05. ②GLUT-4 was expressed by MSCs under any conditions. Compared with normoxia-non-transfection group, hypoxia decreased the expressions of GLUT-4 mRNA and protein significantly (P＜0.05). ③Compared with hypoxianontransfection group, the expression of GLUT-4 〔mRNA（1.756±0.152） fold, total protein in cell （1.653±0.312） fold, protein in plasma membrane （2.041±0.258） fold〕 was increased in hypoxia-transfection group significantly (P＜0.05), but which was lower than that in normoxianontransfection group (P＜0.05). ④There was significantly positive relation between 3H-G intake and GLUT-4 protein expression in plasma membrane (r=0.415, P=0.001).Conclusion GLUT-4 may take part in glucose uptake of MSCs, and the capability of Akt gene to improve MSCs anti-hypoxia may be finished by its role in increasing the expression and translocation of GLUT-4.
Objective To study the effects of glucose and lipid metabolism on gallstone formation. Methods Twenty five patients with gallstones and 25 normal volunteer controls were studied from January to April in 1998. The patients were well matched the control with sex and age (1∶1). In the study, Body Mass Index (BMI) and Waist-to-Hip circumference ratio (W/H) were measured. Blood glucose, glucosylated hemoglobin (HbA1C), insulin, C peptide and all parameters of lipids were detected at fasting state. The glucose,insulin, C peptide were detected again at 2-hour after taking 75g glucose orally.Results The result showed there was no difference on BMI and W/H between the patients and controls. HbA1C、mean fasting and 2hour glucose concentration were not in significantly different between the two groups (Pgt;0.05, Pgt;0.2, Pgt;0.1 respectively). There were 10 patients with abnormal glucose metabolism (7 with NIDDM, 3 with IGT), but only 4 controls were abnoumal (one with NIDDM, three with IGT). The difference was significant (Plt;0.05). Furthermore, the mean fasting and 2hour insulin concentration of gallstone group was higher than that of the control (Plt;0.02, Plt;0.05). And the gallstone group had a higher fasting C peptide concentration than control (Plt;0.05). There was no statistical difference on the parameters of plasma lipid between the tow groups. Conclusion The study suggests that diabetes mellious and hyperinsulinemia acted as an important role on gallstone formation.
Objective To investigate the effect of glucagon-like peptide-1(GLP-1) on impaired glucose tolerance due to stress postoperatively. Methods The rats were allocated randomly to one of three groups, group Ⅰ was subdivided into group Ⅰg which received an intravenous glucose load (0.5 g/kg glucose), and group Ⅰglp which received the same glucose load with GLP-1 (0.3 nmol/kg) during intravenous glucose tolerance test (IVGTT). Rats in group Ⅱg and group Ⅱglp in group Ⅱ were infused respectively the same intravenous glucose tolerance test as group Ⅰ on the first, third and fifth day after 65% liver resection. And rats in group Ⅲ were injected the same glucose load with GLP-1 (0.45 nmol/kg) during IVGTT on the first day after hepatectomy. The peak glucose levels, glucose levels at 30 minutes and the area under the curve (AUC0-30) were investigated among groups. Results The peak glucose levels, glucose levels at 30 minutes and AUC0-30 were significantly lower in group Ⅰglp than those in group Ⅰg. And the values were significantly higher in group Ⅱg than those in group Ⅰg on the first, third and fifth day after operation. There was no significant difference between group Ⅱglp and group Ⅱg in the peak glucose levels on the first day after liver resection, but the peak glucose levels and AUC0-30 were significantly lower in group Ⅲ than those in group Ⅱg and group Ⅱglp, and the glucose levels at 30 minutes were significantly lower in group Ⅲ than those in group Ⅱg too on the first day. The peak glucose levels were significantly lower in group Ⅱglpthan those in group Ⅱg on the third and fifth postoperative day and in group Ⅱglp on the first day too, and the glucose levels at 30 minutes and AUC0-30 were also significantly lower in group Ⅱglp than those in group Ⅱg, but they were similar between group Ⅱglp and group Ⅰg. Conclusion Glucose intolerance is a feature of stress after hepatectomy, and GLP-1, injected in conjunction with the IVGTT, increased the clearance of glucose. The contribution of GLP-1 to reducing blood glucose was decreased significantly at early phase postoperatively, but its action was enhanced by the way of dosage dependence. The action of GLP-1 was enhanced with the degree of stress reduction and then returned to normal.
Objective To investigate the expression of aquaporin-1( AQP-1) in pleural mesothelial cells ( PMCs) and the influence of glucose thereupon. Methods Rat PMCs were isolated, cultured, and divided into two groups, ie. a glucose group, cultured with glucose of different concentrations for 24 hours,and a control group, cultured in D-MEM/ F-12 medium. The 100 mmol / L glucose group was administered at the time points of 6, 12, 18, and 24 hours respectively. RT-PCR and Western blotting were used to analyze the mRNA and protein expression of AQP-1. Results The absorbance values of AQP-1 protein expression were 54. 02 ±4. 61, 127. 84 ±9. 41, and 231. 62 ±22. 63, respectively in the PMCs treated with glucose of the concentrations of 50, 100, and 200 mmol / L, all significantly higher than those in the control group( 22. 45 ±2. 16, all P lt; 0. 01) . The absorbance values of AQP-1 protein expression were 24. 68 ±2. 56, 58. 68 ±3. 67, 89. 61 ±6. 62, and 113. 41 ±7. 65 in the PMCs treated with glucose of the concentration of 100 mmol / L after 6, 12, 18, and 24 hours, all significantly higher than those in the control group ( 11. 81 ±1. 45, P lt;0. 01) .Conclusions Glucose induces the expression of AQP-1 mRNA and protein. AQP-1 participates in the pleural fluid formation.
Abstract： Objective To identify the risk factors for shortterm adverse events in infants with congenital heart diseases receiving open heart surgical correction with cardiopulmonary bypass (CPB), in order to improve the outcome by adopting appropriate treatment measures. Methods We retrospectively analyzed the clinical data of 98 consecutive children with congenital heart diseases who underwent surgical correction with CPB in Beijing Fu Wai Hospital from November 2009 to December 2009. The patients were divided into two groups according to the postoperative complications. Among the patients without complications（n=40）: there were 24 males and 16 females with an age of 7.60±0.40 months and a weight of 7.80±0.30 kg. In the patients with complications (n=58): there were 42 males and 16 females with an age of 6.20±0.40 months and a weight of 6.70±0.20 kg. In both groups, perioperative data were recorded, including preoperative fast blood glucose, creatinine, time of aortic crossclamp, modified or zerobalanced ultrafiltration, postoperative glucose level, concentration of lactate, notrope score and complications. Risk stratification was performed by Risk Adjusted Classification for Congenital Heart Surgery (RACHS-1). Univariate analysis and logistic regression analysis were used to identify the risk factors for shortterm adverse events. Results One patient(1.02%) died of circulatory failure during the perioperative period. Thirtyseven patients [CM(159mm]were supported by at least 2 vasoactive drugs for more than 48hours,29 by mechanical ventilation for more than 24 hours, 5 needed reintubation, 1 experienced tracheotomy, 31 suffered from noscomial infection, 4 had wound infection, 3 developed renal failure, and 1 developed hepatic dysfunction. By logistic regression analysis, age (OR=0.750, P=0.012), percutaneous oxygen saturation (OR=0.840,P=0.005), aortic crossclamp time (OR=1.040, P=0.008), postoperative glucose level (patients with a mean glucose level lower or equal to 8.33 mmol/L had a probability of developing adverse outcomes five times higher; OR=5.051, P=0.011) were found to be the risk factors for shortterm adverse outcomes. Conclusion Age, percutaneous oxygen saturation and aortic crossclamp time are associated with the shortterm adverse outcome of infants undergoing congenital heart disease correction with CPB. The present results do not support perioperative hyperglycemia as a risk factor for adverse outcome.
Objective To study the effects of hypoxic preconditioning on the glucose metabol ism of rat BMSCs and its underlying mechanism so as to provide the theoretical basis for the optimization of the stem-cell based therapy. Methods Density gradient centrifugation method was adopted to isolate rat BMSCs from neonatal SD rats (aged 1-3 days). BMSCs were cultured to 4th passage and divided into 4 groups based on different culture conditions: group A in normoxia condition for 24 hours, group B in 1% O2 for 24 hours, group C in 2-methoxyestradiol (20 μmol/L) for 24 hours before hypoxic preconditioning, and group D in hypoxia-inducible factor 1 (HIF-1) specific siRNA (50 μmol/L) for 12 hours before hypoxicpreconditioning. MTT method was appl ied to evaluate the prol iferation of BMSCs. Biochemical analyzer and Real-timefluorescent quantitative PCR were appl ied to detect the glucose uptake, lactate production, and HIF-1α mRNA and Glut-1mRNA levels of BMSCs. Results MTT showed that the absorbance (A) values were 387.67 ± 58.92, 322.50 ± 50.60, 297.00 ± 53.00, and 286.00 ± 41.00 in groups A, B, C, and D, respectively, showing no significant difference among 4 groups (P gt; 0.05). The levels of glucose uptake and lactate production were higher in group B than in groups A, C, and D, showing significant differences (P lt; 0.05); the levels of groups C and D were higher than those of group A, but showing no significant difference (P gt; 0.05). The mRNA expressions of HIF-1α and Glut-1 elevated significantly in group B when compared with those in group A (P lt; 0.05); groups C and D were significantly lower than group B (P lt; 0.05) and were significantly higher than group A (P lt; 0.05). Conclusion Hypoxic preconditioning can stimulate the glucose uptake and metabol ism of rat BMSCs, whose mechanism is probably related to up-regulating the mRNA expressions of HIF-1α and Glut-1.
Objective To observe the different effect such as high concentration of glucose and high concentration of insulin on GLUT1 of Rabbit Retinal Muuml;ller Cell in vitro. Methods Rabbit retinal Muuml;ller cells were cultured in vitro with suspended constitution，which were divided as the following groups: common control group，high glucose group，insulin group，high glucose combined insulin group. Laser confocal microscope combined with immunocytochemical and fluorescence staining method to quantitatively analyze the expression condition of GLUT1. Results The expression of GLUT1 has been enhanced obviously by high glucose and high insulin，which locates mainly in the cytoplasm that near to the nucleus. Conclusion Rabbit retinal Muuml;ller cells can express GLUT1，and the expression of GLUT1 can be reinforced by high glucose and high insulin. （Chin J Ocul Fundus Dis，2008，24：265-267）
Objective To observe the effects of high concentr at ion glucose on the calcium-activated potassium channel of rabbits′ retinal Müller cells. Methods The rabbits′retinal Müller cells were cultured in vitro under the condition of high concentration glucose, and identified by immunohistochemical staining and transmission electron microscopy. Patch-clamp technique was used to observe the changes of the calcium-activated potassium channel of retinal Müller cells caused by high concentration glucose at different time.Results High concentration glucose could inhibit the calcium-activated potassium channel of cultured retinal Müller cells in a time-dependent manner. Conclusion High concentration glucose may reduce the biological functions of Müller cells by inhibiting calcium-activated potassium channel. (Chin J Ocul Fundus Dis，2003，19：164-167)
The retina of SD rats was incubated in four types of the Eagle solution respectively. The results showed the cAMP level of retinas was the lowest in the hGnMg(high glucose with normal magnesium) solution but the cAMP level was significantly increased in the hGhMg(high glucose with high magnesium) and higher than that of normal control group. The cAMP level was the highest in the nGhMg(normal glucose with high magnesium). The results suggested that magnesium might play an important role in maintaining the normal metabolism of glucose of the retinal tissue. （Chin J Ocul Fundus Dis,1992,8:138-140）