Protective effect of prostaglandin E1 against brain injury induced by hyperoxia in neonatal rats / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the protective effect of prostaglandin E1 (PGE-1) against brain injury induced by hyperoxia in neonatal rats and observe the changes in the expression of glucose-regulated protein 78 (GRP78) and cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), and to provide a theoretical basis for the clinical application of PGE-1 in the treatment of neonatal brain injury induced by hyperoxia.</p><p><b>METHODS</b>Sixty neonatal Wistar rats were randomly divided into air control group, hyperoxic brain injury model group, and hyperoxic brain injury+PGE-1 group. All rats except those in the air control group were treated to establish a hyperoxic brain injury model. From the first day of modeling, the rats in the hyperoxia brain injury+PGE-1 group were intraperitoneally injected with PGE-1 2 μg/kg daily for 7 consecutive days, while the other two groups were treated with normal saline instead. The water content of brain tissue was measured; the pathological changes of brain tissue were evaluated by hematoxylin-eosin staining; the apoptosis of brain cells was assessed by nuclear staining combined with TUNEL staining; the protein expression of GRP78 and CHOP in brain tissue was measured by Western blot.</p><p><b>RESULTS</b>The water content of brain tissue in the hyperoxic brain injury model group was significantly higher than that in the hyperoxic brain injury+PGE-1 group and air control group (P<0.05); the water content of brain tissue in the hyperoxic brain injury+PGE-1 group was significantly higher than that in the air control group (P<0.05). The pathological section of brain tissue showed inflammatory cell infiltration and mild cerebrovascular edema in the brain parenchyma in the hyperoxic brain injury model group; the periparenchymal inflammation and edema in the hyperoxic brain injury+PGE-1 group were milder than those in the hyperoxic brain injury model group. The apoptosis index of brain tissue in the hyperoxic brain injury model group was significantly higher than that in the hyperoxic brain injury+PGE-1 group and air control group (P<0.05); the apoptosis index of brain tissue in the hyperoxic brain injury+PGE-1 group was significantly higher than that in the air control group (P<0.05). The protein expression of GRP78 and CHOP in brain tissue was significantly higher in the hyperoxic brain injury model group than in the hyperoxic brain injury+PGE-1 group and air control group (P<0.05); the protein expression of GRP78 and CHOP was significantly higher in the hyperoxic brain injury+PGE-1 group than in the air control group (P<0.05).</p><p><b>CONCLUSIONS</b>PGE-1 has a protective effect against hyperoxia-induced brain injury in neonatal rats, which may be related to the inhibition of cell apoptosis by down-regulating the expression of GRP78 and CHOP.</p>

Effect of insulin-like growth factor-1 on hyperoxia-induced apoptosis in A549 cells / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the effect of insulin-like growth factor-1 (IGF-1), which can promote cell differentiation and inhibit cell apoptosis, on hyperoxia-induced apoptosis in A549 cells and its anti-apoptotic mechanism.</p><p><b>METHODS</b>A549 cells were sub-cultured, exposed to hyperoxic conditions and were then treated with different concentrations of IGF-1 (1, 10, and 100 ng/mL) for 48 hours. Cell viability was measured by MTT assay. Cell apoptosis was evaluated by Annexin V-FITC/PI double-staining flow cytometry. Expression levels of Bax and Bcl-2 were measured by flow cytometry.</p><p><b>RESULTS</b>The middle-dose and high-dose IGF-1 intervention groups had higher cell viabilities than the hyperoxic exposure group [(64±3)% and (88±4)% vs (51±3)%; P<0.05]. Compared with the air control group, the hyperoxic exposure group had a significantly higher apoptotic rate [(38.3±5.4)% vs (2.4±0.9)%; P<0.05], a significantly lower expression level of Bcl-2 [(72±5)% vs (91±4)%; P<0.05], and a significantly higher expression level of Bax [(54±6)% vs (3±2)%; P<0.05]. Compared with the hyperoxic exposure group, the low-dose, middle-dose, and high-dose IGF-1 intervention groups had significantly lower apoptotic rates [(16.1±4.7)%, (9.2±2.8)%, and (6.9±2.5)% vs (38.3±5.4)%; P<0.05], significantly higher expression level of Bcl-2 [(79±4)%, (94±4)%, and (100±5)% vs (72±5)%; P<0.05], and significantly lower expression level of Bax [(26±4)%, （5±2)%, and (4±2)% vs (54±6)%; P<0.05].</p><p><b>CONCLUSIONS</b>Hyperoxia significantly inhibits proliferation and promotes apoptosis in A549 cells. IGF-1 may promote cell proliferation and inhibit hyperoxia-induced apoptosis in A549 cells by regulating the expression of Bcl-2 and Bax.</p>

Levels of nerve growth factor and interleukin-4 in the induced sputum of children with cough variant asthma / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To examine the levels of nerve growth factor (NGF) and interleukin-4 (IL-4) in the induced sputum of children with cough variant asthma (CVA), with the aim of studying the roles of NGF and IL-4 in childhood CVA.</p><p><b>METHODS</b>Thirty-four children with CVA were enrolled in this study. Twenty healthy children were used as a normal control group. The induced sputum was separated into supernatant and cells. Hematoxylin and eosin staining was used to count differential cells. The expression of NGF and IL-4 in supernatant was measured using ELISA. The mRNA expression of NGF and IL-4 in cells was determined by Real-time PCR analysis.</p><p><b>RESULTS</b>The percentage of eosinophils in the CVA group was significantly higher than in the control group [(13.4±3.6)% vs (2.6±1.7)%; P<0.01]. The expression of NGF and IL-4 protein and mRNA in induced sputum was significantly higher in the CVA group than in the control group (P<0.05). The expression of NGF and IL-4 protein and mRNA was positively correlated with the percentage of eosinophils (P<0.01). The expression of NGF and IL-4 protein and mRNA in induced sputum was significantly reduced in the CVA group after treatment (P<0.05).</p><p><b>CONCLUSIONS</b>Eosinophils infiltration and increased expression of NGF and IL-4 play key roles in the development of childhood CVA, suggesting that they may be useful in the diagnosis and treatment of childhood CVA.</p>

Effects of diesel exhaust particles inhalation on immediate reaction in asthma rats / 中华儿科杂志

<p><b>OBJECTIVE</b>The role of air pollution on asthma can not be ignored, diesel exhaust particles (DEP) in the air is one of the most important pollutants. This study aimed to investigate the effect and mechanism of DEP inhaled on immediate reaction in the asthma rats.</p><p><b>METHOD</b>Sixty male Wistar rats of "Clean" grade, 6 - 7 week-old, with an average weight of (140 +/- 20) g were used in this study. The rats were randomly divided into 6 groups, 10 in each. Group A was treated with normal saline attack as a negative control, Group B with ovalbumin attack as a positive control. After ovalbumin attack, groups C, D, E, F continued to inhale DEP for 1 week, 2 weeks, 3 weeks and 4 weeks, respectively. The concentration of DEP was 200 microg/ml, the animals were subjected to inhalation of ultrasound nebulized DEP for 30 min per day. One week after all the attacks were concluded, Group A was stimulated with normal saline for 30 min, other groups were stimulated with ovalbumin. Then the airway resistance was determined with multi-channel signal acquisition and processing system and compared. The changes in neutrophils, eosinophils, and other inflammatory cells of BALF and the pathological changes in lung tissue, including epithelial cells loss, the inflammatory cells infiltration around the airway, basement membrane fibrosis, goblet cell hyperplasia etc. were observed. The concentration of IL-5 and gamma-interferon in the lung tissues, and the changes of serum IgE etc. were determined.</p><p><b>RESULT</b>Airway resistance values of group A, B, C, D, E, F after ovalbumin excitation for 30 min were (3.56 +/- 0.21), (7.06 +/- 0.63), (6.46 +/- 0.38), (7.47 +/- 0.33), (8.87 +/- 0.61), (11.00 +/- 0.69) cm H2O/(ml.s). No airway hyperresponsiveness occurred in group A, while Groups B, C, D, E, F had higher airway resistance than group A, group E and F had higher airway resistance than that of group B, the differences were statistically significant. And the airway resistance was different in each group among 0 min, 10 min, 20 min and 30 min (F = 160.646, 148.901, 162.204, 156.186, P < 0.01 for both). The time of DEP inhalation and the airway resistance was positively correlated (r = 0.948, P < 0.01); IgE concentrations of the serum between groups B, C, D, E, F was not significantly different (P > 0.05), but higher than that of group A (F = 2.639, P < 0.01). The infiltrated inflammatory cells included eosinophils and lymphocytes, etc. The percentages of neutrophil(%) were (4.3 +/- 2.0), (9.7 +/- 5.2), (10.3 +/- 5.6), (13.0 +/- 5.2), (42.6 +/- 18.3), (55.3 +/- 6.9). The groups E and F had higher percentage than Group A and Group B (F = 114.226, P < 0.01). The percentages of eosinophils(%) were 0, (11.9 +/- 3.8), (15.8 +/- 6.3), (13.0 +/- 4.9), (21.1 +/- 5.6), (27.1 +/- 4.8). The difference between Groups B, C, D, E, F and Group A was statistically significant. There was significant difference between groups C, D, E, F and group B (F = 46.462, P < 0.05); Lung tissue biopsy in group A showed that the epithelial cells were intact, no inflammatory cells infiltrations were found around the airways, instead, mainly ciliated columnar epithelial cells and only a small number of goblet cells were seen without basement membrane fibrosis. With the inhalation of DEP, the epithelial cells showed gradual necrosis, disruption and loss, goblet cells showed hyperplasia, and infiltrations with inflammatory cells were seen around the airway. In the lung tissue, concentrations of IL-5 in group B, C, and E were (12.8 +/- 2.8), (17.1 +/- 5.2), (18.6 +/- 4.2) pg/mg, the difference between groups C, E and group B was statistically significant (F = 4.236, P < 0.01), the difference in gamma-interferon concentration among all groups was not statistically significance (F = 1.185, P > 0.05).</p><p><b>CONCLUSION</b>DEP inhalation increased the airway responsiveness of asthma rats in immediate reaction, promoted the lung epithelial cell loss, inflammatory cell infiltration, basement membrane fibrosis and goblet cell hyperplasia.</p>

Effects of recombinant human insulin-like growth factor-1 on the expression of Clara cell secretory protein in lung of hyperoxia-exposed newborn rats / 中华儿科杂志

<p><b>OBJECTIVE</b>The development of neonatology and the availability of pulmonary surfactant have been helpful in effective reduction of the mortality of very low birth weight infants at the expense of an increasing number of survivors with bronchopulmonary dysplasia (BPD) caused by lung immaturity. BPD is a common syndrome in newborns, especially in preterm infants, when treated with hyperoxia and mechanical ventilation. Unfortunately, there have been no effective measure for the prevention and treatment of BPD. The purpose of this study was to investigate the influence of recombinant human insulin-like growth factor-1 (rh-IGF-1) on cell apoptosis and Clara cell secretory protein (CCSP) expression during the lung injury induced by hyperoxia, so as to assess its effect on the inflammatory lung injury and its developmental repair.</p><p><b>METHODS</b>Eighty full term neonatal Wistar rats under the same condition were divided randomly into four groups on the second day after birth. Group I was air control, group II was exposed to hyperoxia, group III air + rh-IGF-1, and group IV was treated with hyperoxia + rh-IGF-1. The pups in the control group were kept in room air, while pups in hyperoxia group were kept in a Plexiglas chamber and exposed to over 85% oxygen. Pups in group III were under the same raising condition except for exposure to room air and treated with intraperitoneal injection of rh-IGF-1 (1 microg/Kg) everyday from the third day. Pups in group IV were treated with intraperitoneal injection of rh-IGF-1 (1 microg/Kg) everyday from the third day of exposure to hyperoxia. Lung tissue sections of the neonatal rats were stained with hematoxylin and eosin (HE) after 7 d of hyperoxia exposure, expression of CCSP was examined by immunohistochemical method, and apoptotic cell index of lung tissue was calculated by using TUNEL method.</p><p><b>RESULTS</b>It was observed from immunohistochemical examination that positive staining of CCSP was distributed mainly in distal and respiratory bronchioles. The percentage of Clara cells in distal and respiratory bronchioles epithelium decreased in hyperoxia group (32.17 +/- 3.19)% compared to that in air control group (68.32 +/- 2.04)%, P < 0.01. Statistically significant differences were found in intensity of positiveness of Clara cells between hyperoxia (29.45 +/- 5.56) and air control group (42.37 +/- 3.24), P < 0.01. TUNEL assay showed that most apoptotic cells were alveolar and bronchial epithelial cells. The apoptotic index increased significantly in the hyperoxia group (55.77 +/- 6.09)% compared to the air control group (16.41 +/- 4.01)%, (P < 0.01). The positive rate (52.98 +/- 2.68)% of Clara cells and the expression (41.22 +/- 6.36) of CCSP in hyperoxia + rh-IGF-1 group increased significantly when compared with hyperoxia group, and the differences between these two group were also statistically significant (P < 0.01). The apoptotic index increased significantly in the hyperoxia + rh-IGF-1 group (27.98 +/- 3.09)% compared to the hyperoxia group (P < 0.01).</p><p><b>CONCLUSIONS</b>Hyperoxia exposure can promote the pneumocyte apoptosis and inhibit the expression of CCSP. Rh-IGF-1 can remove the block of the formation of lung alveoli, increase the secretion of CCSP, mitigate inflammatory responses in airway and alleviate lung injury via pneumocyte apoptosis. Therefore, the results of this study provide a theoretic and experimental evidence for clinical application of rh-IGF-1 in prevention and treatment of BPD.</p>

Allergic Pneumonia Animal Model Manufacture / 实用儿科临床杂志

Objective To investigate whether the spores from mushroom antigen can cause the allergic pneumonia and manufacture allergic animal model in the C57BL/_6 mouse.Methods Aged 6 weeks old,weight 25-30 g C57BL/_6 mice were collected.In the mouse tail injection compound of spore antigen and the Freud′s adjuvant.Then pours into through the trachea the antigen once a week.The mice were divided into 4 groups.Group A was the normal mouse,Group B was given Freud′s adjuvant(the same method)to determine whether there was affect to the mouse.Group C and D were injected spore antigen 2 and 4 times.When the antigen sensitization finished 1 week later group C and D were completely divided 2 groups,among them one group was inhalation 1.5% spore antigen and induce the acute response.Six hours later the bronchoalveolar lavage fluid(BALF) was collected to observe cell change,and excise the lung tissue to manufacture the pathology specimen,another group had not been induced the acute response and collect the BALF and to exsise the lung tissue directly.Group B were inhalted saline later to collect the BALF and the lung tissue.In the mouse blood serun,enzyme linked immunosorbent assay(ELISA) was used to mensurate antigen specific IgG.Results In group C and D,antigen specific IgG significantly inhanced than that in group A and B(all P

Protective Effects of Prostaglandin E_1 on Newborn Rats with Hypoxic-ischemic Brain Damage / 实用儿科临床杂志

Objective To study the effect of exogenous prostaglandin E 1 (PGE 1) on the superoxide dismutase(SOD) and nitric oxide(NO) levels in brain tissue of neonatal rats with hypoxic-ischemic brain damage(HIBD).Methods Sixty 7-day old newborn Wistar rats to establish HIBD models,intraperitoneally and subcutaneous injected PGE 1 and TMP,then the rats were killed after hypo- xia and ischemia for 48 hours.Take cerebral cortex of arteria carotis ligation side and made them into homogenate to detect SOD and NO levels in brain tissue.Results SOD level in HIBD group was lower,and NO level was higher than those of normal group(P

Effects of Azithromycin on Hyperoxia Induced Lung Injury in Neonatal Rats / 实用儿科临床杂志

Objective To investigate the effects of azithromycin on hyperoxia induced lung injury in neonatal rats.Methods Ninety 2-day-old neonatal rats were randomly divided into 3 groups (30 cases in each group):air control group,hyperoxia model group,azithromycin treated group.The rats in air control group were exposed to indoor air,and the rats in hyperoxia model group and azithromycin group were exposed to 900 mL?L-1 O2 for 14 days.From 2-days-after birth,rats in treated group received intraperitoneal injection of azithromycin (200 mg?kg-1)per day,rats in air control group and hyperoxia model group received intraperitoneal injection of normal saline.Ten rats in each group were executed and their lung tissues were taken out and were observed under a optical microscope on the 3rd,7th,14th days from the start.The expression of interferon gamma(IFN-?),connective tissue growth factor(CTGF) and matrix metalloproteinase-9 (MMP-9) in the lung tissues were detected by immunohistochemistry.Results There was no expression of IFN-? positive cells in air control group,but the expressional intensity level was gradually enhanced as the time of inhaling hyperoxia prolonged in hyperoxia model group,it reached the peak on the 7th day,and then obviously declined on the 14th day,but still higher than that of air control group.The expressional intensity level of IFN-? in azithromycin treated group was lower than that of hyperoxia model group in each time segment,there were significant differences among them(Pa