ABSTRACT
Objective:To explore the effects and mechanism of apigenin on lung ischemia-reperfusion (I/R) injury in mice.Methods:A total of 40 male C57/B6 mice were randomized into 4 groups of sham, I/R, low-dose apigenin and high-dose apigenin (n=10 each). Lung I/R injury model was established by clipping left hilum for 1h and reperfusion for 2 h. Low/high-dose apigenin group received a gavage of apigenin (10/50 mg·kg -1·d -1) for 7 days before lung I/R.After 2-hour reperfusion, lung tissue was collected and lung injury status evaluated and scored by hematoxylin-eosin (H&E) stain; mRNA expression levels of interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α), high mobility group box 1 (HMGB1), prostaglandin-endoperoxide synthase 2 (PTGS2) and glutathione peroxidase 4 (GPX4) were detected by reverse transcription-polymerase chain reaction (RT-PCR); Western blot was utilized for detecting the protein expressions of Bax, Bcl-2 and HIF-1α.Finally, after morinostat activated Hif-1α, the effect of apigenin (50 μmol/L) on hypoxia-reoxygenation (H/R)-induced ferroptosis was further observed in A549 lung epithelial cells. Results:As compared with sham group, lung injury score spiked markedly in I/R group (7.05±0.6 vs.1.25±0.42), pulmonary edema worsened obviously (8.65±1.12 vs.4.17±0.54), the percentage of Tunel positive cells rose significantly (58.22±4.92 vs.8.23±1.22) and mRNA expression levels of IL-1β, TNF-α and HMGB1 increased (7.82±0.16 vs.1.00±0.14, 4.24±0.12 vs.1.00±0.19, 6.24±0.19 vs.1.00±0.11) ( P<0.05); Compared with I/R group, lung injury score declined markedly in low/high-dose apigenin group (4.88±0.31/2.11±0.29 vs.7.05±0.66)( P<0.05), pulmonary edema lessened markedly (6.42±1.03/4.88±1.62 vs.8.65±1.12)( P<0.05) and the percentage of Tunel positive cells (41.46±6.73/16.02±5.31 vs.58.22±4.92) and the mRNA expression levels of IL-1β, TNF-α and HMGB1 became obviously suppressed (5.88±0.13/3.21±0.19 vs.7.82±0.16, 3.56±0.11/2.12±0.09 vs.4.24±0.12, 4.12±0.14/3.12±0.09 vs.6.24±0.19)( P<0.05); protein expressions of HIF-1α and PTGS2 dropped sharply in low/high-dose apigenin group (2.00±0.10/0.93±0.11 vs.2.99±0.06, 4.12±0.14/2.51±0.18 vs.6.11±0.12) while GPX4 protein rose obviously (0.55±0.02/0.83±0.02 vs.0.38±0.04)( P<0.05). In vitro experiments further showed that apigenin could significantly suppress the H/R-induced protein expression of PTGS2 in A549 lung epithelial cells (1.11±0.0 vs.4.55±0.12)( P<0.05) while up-regulating the protein expression of GPX4 (0.93±0.11 vs.0.32±0.04)( P<0.05). The inhibition of PTGS2 protein (4.01±0.12 vs.1.11±0.05) and the up-regulation of GPX4 were significantly blocked (0.52±0.05 vs.0.93±0.11)( P<0.05). Conclusions:Through an inhibition of HIF-1α/ferroptosis axis, apigenin can alleviate lung injury, apoptosis and inflammatory response associated with lung I/R in mice.
ABSTRACT
Objective:To explore the construction and mechanism of Mindin gene specific macrophage knockout mice in acute lung injury induced by lung ischemia-reperfusion injury(IRI).Methods:Mindin gene knockout mice were constructed by CRE-LOP system, Mice were divided into four groups of C57/B6 wild-type mice sham operation(n=10), C57/B6 mice operation(n=10), Mindin-/-macrophage-specific knockout mice operation(n=10)and C57/B6 mice operation + Mindin recombinant protein intervention(n=10). And lung ischemia-reperfusion injury model was established by clamping pulmonary portal.The effects of Mindin gene knockout and recombinant protein intervention on acute lung injury were observed in vivo and in vitro.t-test and ANOVA test were employed for data processing.Results:Mindin gene macrophage specific knockout mice was successfully constructed.Surgery(Mindin-/-)group significantly reduced pulmonary edema, release of inflammatory factors(IL1β: 2.73±0.19 vs. 5.81±0.61; IL-18: 6.52±0.63 vs. 11.03±0.34; TNF-α 2.18±0.14 vs. 4.76±0.20; HMGB1: 4.57±0.33 vs. 8.76±0.87), expression of NLRP3(2.07±0.27 vs. 4.91±0.22)and secretion of GSDMD(2.78±0.37 vs. 5.78±0.29)as compared with surgery group in vivo.In surgery(WT)+ Mindin group, the expression of lung IRI, inflammatory factors and cell pyroptosis were opposite, And the results were consistent in vitro and in vivo.As compared with surgery group, the above parameters were up-regulated in surgery(WT)+ Mindin protein group.And inter-group differences were statistically significant(all P<0.05). In vitro, the expressions of NLRP3(1.00±0.36, 0.41±0.06, 4.13±0.23), GSDMD(1.00±0.17, 0.34±0.16, 6.32±0.46)and integrin β4(1.00±0.11, 0.28±0.07, 3.53±0.17)were detected in different groups including hypoxia-recovery oxygen(HR), HR+ Mindin siRNA and HR+ Mindin protein groups in macrophage cell line(J774A); As compared with HR group, the above parameters were up-regulated in HR+ Mindin protein group and down-regulated in HR+ Mindin siRNA group.And the differences were statistically significant( P<0.05). The expressions of NLRP3(1.00±0.07, 1.13±0.11, 0.51±0.14)and GSDMD(1.00±0.09, 0.87±0.16, 0.37±0.12)were detected in Mindin, Mindin protein+ vehicle and Mindin protein+ integrin β4 knockout groups.The above parameters were down-regulated in Mindin protein+ integrin β4 knockout group as compared with Mindin protein and Mindin protein + vehicle groups.And the inter-group differences were statistically significant(all P<0.05). Conclusions:During pulmonary IRI, Mindin knockdown can alleviate pulmonary IRI.Mindin gene may promote the expression of inflammatory factors, NLRP3 and GSDMD protein by activating integrin β4 and aggravate cell pyroptosis to promote the development of pulmonary IRI.
ABSTRACT
Objective To investigate the training methods and evaluation parameters for donor lung procurement technique in swine models. Methods The surgical skills of donor lung procurement in 15 swine models were summarized. The operation time, objective evaluation parameters before lung perfusion, gross observation after lung perfusion, the type and frequency of intraoperative errors were assessed. Results All donor lung procurement surgeries were successfully completed in 15 swine models. The mean time interval from skin incision to lung perfusion was 22.6 min. Prior to lung perfusion, the oxygenation index of the donor lung was (501±68) mmHg, (404±100) mL (under the pressure of 15 mmHg) for the tidal volume and (29±4) mL/cmH2O for the static compliance. Along with the increasing surgical frequency, the oxygenation index and tidal volume were improved. Favorable lung inflation was obtained after lung perfusion in a majority of swine models. Intraoperatively, multiple operating errors occurred including dissection error, pulmonary arterial intubation error and procedure error, etc. As the frequency of operation increased, the frequency of surgical errors was significantly decreased. Conclusions After certain training for donor lung procurement in swine models, the incidence of intraoperative procedure error is significantly reduced and the quality of the donor lung tends to be enhanced. Objective parameters, such as oxygenation index and the gross shape of the donor lung can be utilized to evaluate the levels of surgical techniques.
ABSTRACT
The article expounds the four signs of the realization of the fast and striking development in the higher learning of medical sciences during the ninth five-year plan. It analyzes the internationalization of higher learning, the developing strategy in the tenth five-year plan of our country, the development of science and technology, the reformation of health system and the challenge and pressure in the fast development of the higher learning of medical sciences, with which the higher medical education is confronted in the 21th century. It also points out the stable scale, the adjustment of structure, the reinforcement of the teaching, the fundamental policy and the teaching construction strategy in the development of the higher learning of medical sciences in the new age. Besides, it dwells on the reformation thinking about the teaching ideology and concept, the personnel training model the content, method and means of teaching as well as the system of teaching management.