ObjectiveTo observe the effect of integrin β8 on the neuronal apoptosis after hypoxia ischemia (HI) in astrocyte/neuron co-culture system. MethodsAstrocytes and neurons were cultured in vitro from cerebral cortex of the P1-3 days Sprague Dawley rats and E16 days fetal rats, respectively. Immunocytochemistry staining was used to identify the purity of cells. Integrin β8 mRNA expression was qualified in the astrocytes at 12 hours, 1 day, and 2 days after HI and reoxygenation (experimental group) and in normal astrocytes (control group) by RT-PCR. Integrin β8 small interering RNA (siRNA) system was established to specifically block astrocyte β8 expression, the efficiency of integrin β8 inhibition was detected by real-time fluorescent PCR. The astrocytes and neurons were co-cultured to established the astrocyte/neuron co-culture system. The neuronal apoptosis was detected with TUNEL in the normal neurons/astrocytes group (co-cultured HI group), the astrocytes infected by integrin β8 siRNA for 2 days/normal neurons group (β8 RNA interference group), and normal neurons in vitro with HI treatment group (HI group) at 1 day after HI and reoxygenation. The normal neurons without treatment as control (control group). ResultsGlial fibrillary acidic protein and neuronal nuclei staining suggested a purity of more than 90% in cultured cells. HI resulted in an increase of integrin β8 mRNA expression at 12 hours after reoxygenation in astrocytes, which peaked at 1 day after reoxygenation, then slowly decreased and remained higher at 2 days, showing significant differences between control group and experimental group and among different time points in experimental group (P<0.05). RNA interference efficiency was most significant at 2 days after astrocytes infected with integrin β8 siRNA (P<0.05). The neuronal apoptosis was significantly increased in HI group, co-cultured HI group, and β8 RNA interference group when compared with control group (P<0.05). But neuronal apoptosis index (AI) was significantly decreased in co-cultured HI group and β8 RNA interference group when compared with HI group (P<0.05). The significant difference of AI was found between co-cultured HI group and β8 RNA interference group (P<0.05). ConclusionIntegrin β8 expression can be induced with hypoxic-ischemic brain damage, leading to decreased AI of neurons and obvious protective effect.
ObjectiveTo investigate the influence of hypoxia on pro-metastasis induced by epithelial-mesenchymal transition (EMT) of human lung adenocarcinoma. MethodsThe human lung cancer cell line H460 was cultured in hypoxic condition and the morphologic changes of the cells were observed under the microscope. The EMT-related markers including E-cadherin and vimentin were detected by Western blot. Transwell migration assay and transwell invasion assay were employed to detect the migratory and invasive activity of cancer cells. ResultsHypoxic induced morphological changes were consistent with the mesenchymal phenotype, such as an elongated fibroblastic morphology, and conversion from a tightly packed epithelial cobblestone pattern to a loosely packed scattered phenotype. Compared with the control group, hypoxic attenuated the quantity of E-cadhenrin, but increased vimentin, which resulted in promotion of migration and invasion of H460. ConclusionHypoxia induces EMT in H460 and enhances the invasive and migratory abilities of lung cancer cells.
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 investigate the effect of chronic altitude hypoxia exposure on serum lipoprotein levels in healthy subjects and patients with pulmonary hypertension, and whether there is a difference in serum lipoprotein levels between patients with pulmonary hypertension at middle and high altitude. Methods The case data of 245 Han patients with COPD complicated with pulmonary hypertension admitted to the Affiliated Hospital of Qinghai University from January 2018 to September 2022 were retrospectively analyzed. According to the altitude of their long-term residence before onset, the patients were divided into two groups, 119 cases in the middle altitude group (1500 m~2500 m). 126 cases were in the high altitude group of 2500 m~4500 m. In addition, the physical examination data of 50 healthy people in the intermediate and high altitude groups were collected as the control group (the age and gender of the healthy people in the same altitude group were similar to those in the COPD-PH group), a total of 4 groups were collected. The general data, pulmonary artery systolic blood pressure (PASP), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) of the four groups were compared, and the correlation between pulmonary artery systolic blood pressure (PASP) and related variables was analyzed. ResultsThere were no significant differences in age, gender, smoking and drinking between the healthy control group and COPD-PH group (all P>0.05). There were significant differences in body mass index, PASP, TC, TG, HDL-C, LDL-C, TG/HDL-C, HDL-C/LDL-C between the healthy control group and the COPD-PH group (all P<0.05). In the healthy control group, only BMI was significantly different between the high altitude group and the middle altitude group (P<0.05). In the COPD-PH group, PASP, BMI, TC, HDL-C and TG/HDL-C in the high altitude group were significantly different from those in the moderate altitude group (all P<0.05). There were no significant differences in age, gender, smoking, drinking, TG, LDL-C and HDL-C/LDL-C between the two groups (all P>0.05), when gender, age, altitude, body mass index, PASP, smoking and drinking were included in the multi-factor linear regression equation of lipoprotein (TC, TG, HDL-C and LDL-C), it was found that different elevations (middle and higher elevations) only had statistically different effects on HDL-C (b=-0.046, t=-2.209, P=0.028). Correlation analysis showed that PASP was not correlated with age, altitude, body mass index and blood lipids (TC, TG, HDL-C, LDL-C) in the healthy control group (all P>0.05). However, in the COPD-PH group, PASP was negatively correlated with blood lipid indicators (TC, HDL-C and LDL-C). PASP was positively correlated with altitude (a risk factor for hypoxia). ConclusionsHypoxia environment factors characterized by altitude are closely related to the severity of pulmonary artery pressure in patients with COPD-PH, and higher pulmonary artery systolic pressure is closely related to lower levels of TC, HDL-C and LDL-C.
To review the role of hypoxia inducible factor 1α (HIF-1α) in hypoxic-ischemic injury and its repair, and to analyze the possible mechanisms. Methods Recent l iterature on HIF-1α and its role in hypoxic-ischemic injury was reviewed and analyzed. Results HIF-1α was involved in the hypoxic-ischemic injury of various organs or tissues and their repair processes. Conclusion HIF-1α has a potential to treat common cl inical hypoxic-ischemic injuries and has a promisingfuture for appl ication.
Objective Application of auditory brainstem response (ABR) in the study on the relationship of neonates with hypoxic-ischemic encephalopathy (HIE) and the children with hearing loss and auxiliary determine the prognosis of encephalopathy. Methods We prospectively selected neonates diagnosed as HIE in the department of neonatology of the Chengdu Women and Children Central Hospital from January, 2006 to June, 2008. Neonatal ABR was tested and the prognosis of neonates were observed through 3-year followed up in order to analyze the relationship between HIE severity and the severity of hearing handicap and the relationship between the severity of hearing handicap and prognosis. Statistical analysis was performed using SPSS 18.0. χ2 test was used to compare the rate between groups. Results 40 cases involving 80 ears were included, of which 33 cases accomplished the 3-year follow-up for prognosis. The results showed that, 86.3% HIE neonates had hearing handicap (mainly mild hearing loss, 40.0%). Medium-severe HIE groups had more serious hearing handicap than Mild HIE group with a statistical significance (continuity correction χ2=7.383, P=0.007). ABR results showed that, mild HIE is mainly manifested as I wave PL prolonged or poorly differentiated, accounting for 78.1%; medium - severe HIE are mainly manifested as III and V wave PL prolonged central segment abnormalities, accounting for 95.8%; the hearing threshold no more than 60 dB group had better prognosis than the hearing threshold more than 60 dB group prognosis (Fisher exact probability P=0.001). Conclusion ABR reflects that HIE severity and was positively related to the severity of hearing handicap. The more serious hearing loss in neonates is, the worse prognosis the neonates have. ABR can be used to assist the assessment of the prognosis of neonatal HIE.
ObjectiveTo discuss the evaluation of clinical grading for neonates with hypoxic-ischemic encephalopathy (HIE) by diffusion weighted imaging (DWI). MethodsWe retrospectively analyzed the DWI findings of 39 neonates with HIE diagnosed by clinical criteria from December 2009 to July 2013. Abnormal signals were observed for 23 neonates (59%). These neonates were divided into three groups (group A, B and C) according to the shape and range of abnormal signals. Then Kappa test was performed between groups of different clinical grading (light, medium, severe). ResultsFor groups arranged based on abnormal signals and clinical grading, the Kappa value of the consistency test was 0.797 (P < 0.001). ConclusionsDWI negativity cannot exclude the existence of HIE. However, when abnormal signals occur, we can infer the severity in neonates with HIE according to the shape and range of abnormal signals by DWI.
ObjectiveTo investigate the effect of sex on learning and memory ability of newborn mice with hypoxic-ischemic brain injury.MethodsFifty C57BL/6 mice aged 10 days were divided into hypoxia-ischemia group and sham group according to the random number table method, and there were 28 in the hypoxic-ischemic group and 22 in the sham group with half female and half male respectively. In the ischemia-hypoxia group, the left common carotid artery was ligated and then the mice were placed in 34℃ hypoxia chambers with 8% oxygen and 92% nitrogen mixture for 45 minutes. In the sham group, only the skin of the left neck was cut and sutured. After 2 months, Y maze test and Morris water maze test were used to evaluate the learning and memory ability of mice.ResultsThe success rate of the hypoxic-ischemic group was 71.4% (20/28), and that of the sham group was 100.0% (22/22), a total of 42 mice were enrolled in the experiment. In Y maze test, there were differences in entries and total distance of new arms between the two groups (entries: F=16.068, P<0.001; total distance: F=8.532, P=0.007); compared between different groups in the same gender, the entries and total distance of new arms in the hypoxic-ischemic group were lower than those in the sham group with statistically significant differences (entries in males: P=0.001, entries in females: P=0.012; total distance in males: P=0.010, total distance in females: P=0.046). Compared between males and females in the same group, the entries and total distance of new arms of females were higher than those of males in the hypoxic-ischemic group, with statistically significant differences (P=0.039, 0.043). In Morris water maze test, the escape latency of positioning navigation in the hypoxic-ischemic group was higher than that in the sham group, and males showed more obviously poor performance (P<0.001); in the experiment of space exploration, differences were found in the duration of stay and the target quadrant entries between the two groups (duration of stay: F=8.297, P<0.001; entries: F=4.042, P=0.014), and there were statistically significant differences in the same gender males and females in the hypoxic-ischemic group and the sham group (duration of stay in males: P=0.003, duration of stay in females: P=0.038; entries in males: P=0.006, entries in females: P=0.041). Compared between males and females in the same group, the duration of stay and the target quadrant entries of females were higher than those of males in the hypoxic-ischemic group, with statistically significant differences (duration of stay: P=0.018; entries: P=0.032).ConclusionsThe learning and memory ability of newborn mice may be slightly impaired after hypoxic ischemic brain injury. There is significant difference in the effect on learning and memory ability between different genders, and the effect on males is higher than that on females.
Objective To investigate the influence of hypoxic preconditioning on pulmonary structure of rats exposed to simulated high altitude hypoxia and to explore the role of hypoxia inducible factor-1α（HIF-1α）.Methods Fifty-six Wistar rats were randomly divided into 7 groups(n=8 in each group),ie,a normal control group(N group)，an acute hypoxic control group(H0 group)，an acute hypoxic group(H1 group)，a 3 000 m hypoxic preconditioning group(C3.0 group)，a 3 000 m hypoxic preconditioning + acute hypoxic group (C3.1 group)，a 5 000 m hypoxic preconditioning group(C5.0 group)，and a 5 000 m hypoxic preconditioning + acute hypoxic group(C5.1 group).After treated with hypoxic preconditioning，the animals were exposed to simulated altitude of 6 000 m for 24 hours.Then the protein and mRNA expression of HIF-1α in lung of N，H0，C3.0 and C5.0 groups were assessed by Western blot and RT-PCR，respectively.The lung structure in N，H1，C3.1 and C5.1 groups was observed by light microscope and electron microscope.Results Pulmonary interstitial edema was apparently observed in H1 group，while significantly relieved in two hypoxic preconditioning groups.HIF-1α protein was not detected in rat lungs by Western blot analysis.Compared to N group，the levels of HIF-1α mRNA significantly increased in C3.0 group and C5.0 group(both Plt;0.01).Conclusions Hypoxic preconditioning can relieve hypoxic pulmonary interstitial edema and increase HIF-1α mRNA expression in rat lungs.HIF-1 may be involved in the process of hypoxic preconditioning in rat lungs.
Objective To evaluate the efficacy and safety of Shengmai injection for hypoxic-ischemic encephalopathy (HIE). Methods We searched MEDLINE (1966 to February 2007), EMBASE (1980 to February 2007), CBM (1978 to 2006), CNKI (1979 to February 2007), VIP (1989 to February 2007), and handsearched five Journals on Pediatrics. We evaluated features of quality of included studies, including randomization, blinding, allocation concealment and loss of follow-up. Meta-analyses were performed using The Cochrane Collaboration’s RevMan 4.2.8. Results Seven randomized controlled trials were included. The cure rate on day 5 in the Shengmai injection group was higher than in the control group (RR 1.55, 95%CI 1.25 to 1.93), but this rate was similar on day 10 (RR 0.74, 95%CI 0.43 to 1.29). No significant difference in cure rate was noted between the Shengmai injection group and naloxone group (RR 0.88, 95%CI 0.53 to 1.46). No significant differences were observed in mortality (RR0.44, 95%CI 0.16 to 1.19) and mutilation rate (RR 0.58, 95%CI 0.21 to 1.56) between the Shengmai injection group and the control group. For those babies suffering from HIE combined with myocardial damage, Shengmai injection could speed up the recovery of ECG (WMD=–2.02, 95%CI –2.76 to –1.28) and myocardial enzymogram (CK-MB: WMD= –4.78, 95%CI –6.77 to –2.79; CK-BB: WMD=–2.68, 95%CI –4.58 to –0.78). Significant differences in NBNA score were noted between the Shengmai injection group and the control group on day 5 (WMD=4.05, 95%CI 2.47 to 5.63) and day 10 (WMD=3.50, 95%CI 2.26 to 4.74). No fatal side effects were reported. Conclusions Shengmai injection has certain therapeutic values in treating HIE. Shengmai injection can speed up the recovery ECG, CK-BM and CK-BB of HIE patients, especially in those who have myocardial damage. Shengmai injection can also improve the NBNA score. However, because of the low statistical power and high risks for selection bias, performance bias and measurement bias in the included trials, these conclusions need to be interpreted cautiously.