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61.
AIM: To study the protective effect of brain-derived neurotrophic factor (BDNF) on vascular endothelial cells with H2O2-induced oxidative injury. METHODS: Human umbilical vein endothelial cells (HUVECs) were cultured in vitro, and the oxidation injury model of HUVECs was established by treatment with H2O2. The oxidatively injured HUVECs were cultured with different concentrations (1, 10 and 100 μg/L) of BDNF. At the same time, the control group (no injury), PBS treatment after H2O2 injury group and TrkB inhibitor group (with 100 μg/L BDNF and 1: 1 000 TrkB inhibitor) were also set up. The viability of the HUVECs was detected by MTT assay. The levels of LDH, MDA, SOD and GSH were measured. The releases of NO, ET-1 and ICAM-1 were analyzed by ELISA. The changes of ROS production and cell apoptosis were evaluated by flow cytometry. The protein levels of TrkB, p-TrkB, cleaved caspase-3, Bcl-2 and Bax were determined by Western blot. RESULTS: Compared with uninjured control group, in H2O2 oxidative injury plus PBS treatment group, the viability of the cells was decreased significantly, the LDH and MDA levels were increased significantly and the activities of SOD and GSH were decreased significantly. The NO secretion was decreased, and the ET-1 and ICAM-1 concentrations were increased significantly. The ROS content and apoptotic rate were increased significantly. The protein levels of cleaved caspase-3 and Bax were increased but Bcl-2 protein expression was decreased significantly. Compared with PBS treatment group, in H2O2-injured HUVECs treated with different concentrations of BDNF, the cell viability was gradually increased, the LDH and MDA levels were decreased and the activities of SOD and GSH were increased gradually. The secretion of NO was increased but ET-1 and ICAM-1 were decreased gradually. The ROS content and apoptotic rate were decreased significantly. The TrkB and p-TrkB levels were significantly increased significantly, the protein expression of cleaved-caspase 3 and Bax was decreased gradually and the Bcl-2 protein expression increased gradually. The role of BDNF was inhibited by TrkB inhibitor. CONCLUSION: BDNF protects HUVECs from oxidative injury by binding with TrkB to activate the BDNF-TrkB signaling pathways. 相似文献
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AIM: To investigate the changes of peroxisome proliferator-activated receptors (PPAR)α/peroxisome proliferator activated receptor coactivator 1 alpha (PGC-1α) in doxorubicin (DOX) induced dilated cardiomyopathy (DCM) and its effect on the energy metabolism and myocardial function in mice. METHODS: Forty mice were randomly divided into 4 groups: control group, DOX group, PPARα inhibitor group and PPARα agonist group. The DCM model was established by injection of DOX. The protein levels of PPARα/PGC-1α were detected. The PPARα inhibitor and PPARα agonist were used 2 weeks beforeinjection of DOX. The contents of adenine acid and phosphocreatine (Pcr) in the mitochondria were measured by high-performance liquid chromatography (HPLC). The ANT activity was analyzed by the atractyloside-inhibitor stop technique. The changes of the echocardiography and hemodynamics were also observed. RESULTS: DOX induced DCM model was successfully established. The protein levels of PPARα and PGC-1α in control group were significantly higher than those in DOX group (P<0.05). Both of the high-energy phosphate contents and the transport activity of ANT were decreased in DOX group (P<0.05), and the hemodynamic parameters were disordered (P<0.01). Compared with DOX group, PPARα inhibitor pre-treatment significantly reduced the PPARα/PGC-1α expression. Meanwhile, high-energy phosphate contents in the mitochondria and the ANT transport activity of the mitochondria decreased, as well as the left ventricular function (P<0.05). On the other hand, PPARα agonist significantly increased the expression of PPARα and PGC-1α, and improved the transport activity of ANT. In addition, the hemodynamic parameters were ameliorated, but the high-energy phosphate contents of the mitochondria did not significantly change. CONCLUSION: PPARα/PGC-1α plays an important role in the regulation of ANT transport activity in dilated cardiomyopathy induced by DOX, and the activation of PPARα/PGC-1α has protective effects on the DCM induced by DOX. 相似文献
63.
AIM: To investigate the effect of rosiglitazone, a peroxisome proliferators-activated receptor γ(PPARγ) agonist, on the expression of PPARγ, the activation of NF-κB and intestine injury in the rats undergoing orthotopic autologous liver transplantation(OALT).METHODS: Sprague-Dawley male rats were randomly divided into 4 groups:control group, sham group, OALT group and rosiglitazone(0.3 mg/kg, iv) pretreatment(ROS+OALT) group. The OALT model was established, and the intestinal tissues were collected 8 h after the liver reperfusion. The intestinal tissue sections were stained to visualize the damage. The expression of PPARγ and NF-κB in the tissues, the concentrations of diamine oxidase(DAO) and fatty acid-binding protein 2(FABP2) in the serum and the concentration of TNF-α and IL-6 in the tissues were measured.RESULTS: Compared with sham group, the intestinal mucosa of the rats showed obvious pathological injury after liver reperfusion in OALT group and ROS group, the Chiu,s scores of intestinal mucosa was significantly higher, and the serum concentrations of DAO and FABP2 increased(P<0.05). After rosiglitazone pretreatment, the injury of intestinal mucosa of the rats was alleviated, the Chiu,s scores was lower and the serum concentrations of DAO and FABP2 decreased(P<0.05), the PPARγ expression was obviously up-regulated in the intestinal tissues, the nuclear translocation of NF-κB was reduced and the concentrations of IL-6 and TNF-α were decreased.CONCLUSION: During perioperative period of OALT in rats, the inflammatory responses are obvious. Furthermore, obvious intestinal injury occurs. PPARγ agonist rosiglitazone obviously up-regulates PPARγ expression and inhibits the inflammation in the intestines, thus protecting against intestinal injury in rats undergoing OALT. 相似文献
64.
AIM: To explore the effects of eplerenone on the expression and activity of aortic endothelial nitric oxide synthase(eNOS) in high salt-induced hypertensive rats.METHODS: Male Wistar rats(4 week old, weighting 50~60 g) were randomly divided into control group, high-salt diet group and eplerenone group. The rats in control group were fed with ordinary rodent animal diet, the rats in high-salt group and eplerenone group were exposed to 5% salt diet for 16 weeks and administrated with the same dosage of saline or eplerenone(40 mg·kg-1·d-1) by gavage for 4 weeks, respectively. Systolic blood pressure(SBP) was measured by tail-cuff every 2 weeks. The rats were sacrificed after 16 weeks and the thoracic aorta was collected. The aldosterone content in the aorta was measured by ELISA. The protein levels of mineralocorticoid receptor(MR) and eNOS were determined by Western blot. The activitie of constitutive NOS(cNOS) was measured by chemocolorimetry. The protein localization of eNOS, neuronal nitric oxide synthase(nNOS) and MR was observed by immunohistochemistry.RESULTS: A process of 8-week high-salt diet increased SBP gradually. SBP in the rats exposure to high salt for 16 weeks was significantly higher than that in control group(P<0.05). After 4 weeks of eplerenone treatment, SBP in the rats was significantly lower than that before treatment(P<0.05). Compared with control group, the aldosterone content in the aorta were significantly increased in high-salt diet group and eplerenone group(P<0.05), the expression level of MR also increased significantly(P<0.05). Compared with control group, both eNOS protein expression(P<0.05) and cNOS activity in high-salt diet group were significantly decreased(P<0.05). The protein expression of eNOS as well as cNOS activity in aorta increased significantly in eplerenone group compared with high-salt diet group(P<0.05).CONCLUSION: Aldosterone content in aorta of high-salt-induced hypertensive rats increases significantly. Aldosterone attenuates the protein expression of eNOS and reduces the enzyme activity through the activation of mineralocorticoid receptor. The selective mineralocorticoid receptor antagonist eplerenone enhances the protein expression of eNOS and its activity, thereby improves eNOS function. 相似文献
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为研究病毒与机体的相互作用,本研究参考GenBank中鸡Toll样受体21 (ChTLR21)的基因序列设计实时定量PCR特异性引物,以鸡核糖体蛋白L4 (RPL4)为内参基因,建立检测ChTLR21 mRNA相对转录水平的实时定量PCR方法,分析ChTLR21在禽传染性喉气管炎病毒(ILTV)感染的鸡胚成纤维细胞(CEF)中和感染SPF雏鸡免疫器官脾脏、法氏囊和胸腺组织中的转录水平.结果显示:ILTV感染CEF后2h、4h、8h和18h时间点ChTLR21 mRNA转录水平分别为未感染对照细胞的1 540.53、0.98、1.19和3.70倍.但仅在ILTV感染2h时引起ChTLR21转录水平升高,与对照组相比差异显著(P<0.05).ILTV感染SPF雏鸡后6h、24 h和30 h脾脏中ChTLR21 mRNA转录水平分别为未感染对照的56.34、59.85和3.61倍;法氏囊中分别为0.03、25.98和3.08倍;胸腺中分别为2.52、50和7.32倍.在感染初期,脾脏中ChTLR21转录量显著升高,随后有所降低,但均高于未感染对照(p<0.05);法氏囊中仅在感染6h时呈显著抑制(p<0.01);胸腺中呈波动性转录水平升高,但与对照组无统计学差异(p>0.05).本研究证明ChTLR21参与了鸡体对ILTV感染的应答,并在体内外感染模型中呈现不同的表达规律. 相似文献
69.
Two plant species, tomato (Lycopersicon esculentum Mill.) and bitter gourd (Momordica charantia), were used for in‐depth studies on the dynamics of silicon (Si) uptake and translocation to the shoots and compartmentation of Si in the roots. The experiments were conducted under controlled environmental conditions in nutrient solutions, which were partly amended with 1 mM Si in the form of silicic acid. At harvest, xylem exudates were collected, and Si concentrations and biomass of roots and shoots were determined. Mass flow of Si was calculated based on the Si concentration of the nutrient solution and transpiration determined in a parallel experiment. Plant roots were subjected to a fractionated Si analysis, allowing attributing Si to different root compartments. Silicon concentrations in the roots compared to the shoots were higher in tomato but lower in bitter gourd. A more ready translocation from the roots to the shoots in bitter gourd was in agreement with Si concentrations in the xylem exudates which were higher than in the external solution. In tomato, the xylem‐sap Si concentration was lower than in the nutrient solution. Calculated Si mass flow to the root exceeded Si uptake in tomato, which was consistent with the measured accumulation of Si in the root water‐free space (WFS). In contrast, Si concentration in the root WFS was lower than in the nutrient solution in bitter gourd, reflecting the calculated Si depletion at the root surface based on the comparison of Si mass flow and Si uptake. Within the roots, more than 80% of the total Si was located in the cell wall and less than 10% in the cytoplasmic fractions in tomato. In bitter gourd, between 60% and 70% of the total root Si was attributed to the cell‐wall fraction whereas the proportion of the cytoplasmic fraction reached more than 30%. Our results clearly confirm that tomato belongs to the Si excluders and bitter gourd to the Si‐accumulator plant species for which high Si concentrations in the cytoplasmic root fraction appear to be characteristic. 相似文献
70.
《African Zoology》2013,48(2):407-411
Two generations of gustatory organs occur during amphibian ontogeny in frogs and salamanders (Anura and Caudata), and are classified as taste buds or taste discs. Taste buds are present in larval forms, whereas taste discs are typical for adults. The little research done on Gymnophiona suggests that only taste buds are present in aquatic forms (larvae and adults), and adults of the only terrestrial species studied had taste buds. Here we investigate the nature of gustatory organs in a terrestrial caecilian, Boulengerula boulengeri (Herpelidae), from Tanzania using standard light and scanning electron microscopy. We found only taste bud type organs to be present in B. boulengeri. These occur mainly in the mucosa of the front part of the oral cavity, usually near the teeth. Our results suggest that B. boulengeri possesses only one type of gustatory organ during its ontogeny. 相似文献