Objective To investigate the effects of extracts of Pinellia ( EP) on a rat model of airway mucus hypersecretion induced by LPS. Methods Thirty Wisatr rats were randomly divided into 5 groups, ie. a blank group, a model group, and three EP groups treated with different doses of EP. There were 6 rats in each group. Airway mucus hypersecretion model was established by intratracheally instillation of LPS in the model group and three EP groups. The rats in three EP groups were orally administered with EP at dosages of 10 g/kg, 30 g/kg and 60 g/kg respectively for 4 days. The expression of Mucin 5AC ( MUC5AC) protein in airway was assayed by immunohistochemistry. The mRNA expressions of MUC5AC and Aquaporin-5( AQP-5) in lung tissue were detected by RT-PCR. ELISA technique was performed to detect TNF-αin bronchoalveolar lavage fluid( BALF) . Results LPS significantly stimulated the mRNA and protein expression of MUC5AC in lung and TNF-αlevel in BALF, and inhibited the expression of AQP-5 mRNA in lung. The EP at dosages of 10 g / kg and 30 g/ kg had little effect on mucus hypersecretion. While 60 g/kg of EP could significantly inhibited the expression of MUC5AC, and decreased the release of TNF-α in BALF. The AQP-5 mRNA was also up-regulated by 60 g /kg of EP. The expression of MUC5AC mRNA was positively correlated with level of TNF-α( r = 0. 948, P lt;0. 05) ; AQP-5 mRNA was negatively correlated with MUC5AC mRNA and TNF-α( r = - 0. 955, P lt; 0. 05; r = - 0. 909, P lt; 0. 05) . Conclusion EP ( 60 g/ kg) can significantly attenuated airway mucus hypersecretion in rats.
ObjectiveTo establish 16HBE cell lines stably expressing glutathione S-transferase mu 5 (GSTM5) gene, and explore the mechanism of GSTM5 nuclear translocation. MethodsRecombinant lentiviral expression vector containing GSTM5 gene was constructed and lentivirus was produced. After lentivirus infection of 16HBE cells, 16HBE-GSTM5 cell lines were obtained by screening with puromycin. Expression of GSTM5 in different cells was examined by RT-qPCR and Western blot. The nuclear translocation of GSTM5 was observed by confocal laser scanning microscope, after the 16HBE-GSTM5 cell lines were treated with tumor necrosis factor-α (TNF-α; 10 ng/ml) for 0.5 hour. ResultsLentiviral expression plasmids, PLVX-puro-3*flag-SBP-GSTM5-C and PLVX-puro-GSTM5-SBP-3*flag-N, were constructed and lentiviral particles were successfully packed. After infected with lentivirus and screened by puromycin, two cell lines, 16HBE-GSTM5-SBP-3*flag-N and 16HBE-3*flag-SBP-GSTM5-C, were obtained. GSTM5 expression in these two cell lines was significantly higher compared with the control group and parental cells. After treated with TNF-α for 0.5 hour, the nuclear translocation of GSTM5 in 16HBE-GSTM5-SBP-3*flag-N was much more obviously than that in 16HBE-3*flag-SBP-GSTM5-C. ConclusionThe N-terminal region of GSTM5 is critical for nuclear translocation induced by TNF-α, which is mediated by a novel and non-classical nuclear localization signal.
Objective To investigate the effects of mechanical ventilation( MV) via different tidal volume ( VT) in combination with positive end expiratory pressure( PEEP) on dogs with acute lung injury( ALI) . Methods Dog model of oleic acid-induced ALI was established. And after that animals were randomized into different MV groups ( included low VT group, VT =6 mL/kg; and high VT group, VT =20 mL/kg) and ventilated for 6 h with a PEEP of 10 cmH2O. Arterial blood gas wasmeasured before, during and after ALI model was established ( at 1 h,2 h, 4 h and 6 h during MV) . The albumin concentration in BALF and pathological change of the lung tissue were evaluated in order to determine the lung injury while animals were sacrificed after 6 h MV. Results ALI model was successfully established ( 2. 50 ±0. 80) hours after oleic acid injection. Arterial pH decreased much severer in the low VT group than the high VT group( P lt;0. 01) . PaO2 and SaO2 in ventilation groups decreased after modeling but increased after MV, and PaO2 and SaO2 were significantly higher in the low VT group than the high VT group after 6 h MV( P lt;0. 05) . PaCO2 fluctuated less in the high VT group, while it increased significantly in the low VT group after MV( P lt; 0. 01) . Oxygenation index( PaO2 /FiO2 ) was lowered after modeling( P lt; 0. 01) , decreased to about 190 mm Hg after 1 h MV. And PaO2 /FiO2 in low VT group was significantly higher than the high VT group after 6 h MV( P lt; 0. 05) . BALF albumin concentration and the lung injury score in the low VT group were both significantly lower than the high VT group( both P lt; 0. 05) . Conclusions Ventilation with PEEP could improve the oxygenation of ALI dogs, and low VT ventilation improves the oxygenation better than high VT. Otherwise, low VT could induce hypercapnia and ameliorate lung injury caused by high VT MV.