[The characteristics of plasma lipids in silicosis rat models were studied based on lipid metabolomics].

Objective: To screen the differential metabolites and metabolic pathways in silicosis model by analyzing plasma metabolomics of silicosis rats. Methods: In May 2021, twenty male SD rats were randomly divided into control group (C), 1-week silicosis group (S1W), 2-week silicosis group (S2W) and 4-week silicosis group (S4W), with 5 rats in each group. Rats were intratracheally instillated with 1ml crystalline SiO(2) suspension (50 mg/ml) or normal saline and were sacrificed after 1 week, 2 weeks and 4 weeks, HE staining was used to observe the lung pathology of rats. The plasma samples were analyzed by UPLC-IMS-QTOF mass spectrometer to screen out potential differential metabolites in silicosis models and analyze their lipid enrichment. Results: HE results showed that nodules formed in the silicosis model group, and with the extension of time, nodules gradually increased and alveolar structure was gradually destroyed. Metabolomics screened out 14 differential metabolites in S1W, 24 in S2W, and 28 in S4W, and found that the differential metabolites were mainly enriched in the metabolism of glycerophospholipid metabolism, fatty acid degradation, Glycosylphosphatidylinositol (GPI) -anchor biosynthesis, fatty acid elongation and other metabolic pathways. Conclusion: There are significant changes in plasma lipid metabolites in silicosis rat models.

Upregulation of miR-335 reduces myocardial injury following myocardial infarction via targeting MAP3K2.

OBJECTIVE: Acute myocardial infarction (AMI) is a serious cardiovascular disease with a high incidence worldwide and the main cause of sudden cardiac death. The aim of this article was to study the protective role of miR-335 in myocardial infarction (MI) and the underlying molecular mechanism. MATERIALS AND METHODS: Thirty Sprague Dawley (SD) rats were randomly divided into sham group, MI + NC group and MI + agomiR-335 group. The expression of miR-335 in rat myocardium was detected by quantitative Real Time-Polymerase Chain Reaction (RT-PCR). Western blot was performed to detect the expression of TNF-α, IL-6, IL-1ß, Caspase-3, Cleaved Caspase-3 (C-Caspase-3) and MAP3K2 in rat myocardium. On the 7th day of the establishment of the rat MI model, a high-resolution small animal ultrasound system was utilized to detect the cardiac function of the rats, and the heart tissues and blood samples of the rats were collected. The corresponding kits were purchased to detect the contents of LDH, CK-MB, MDA and SOD in rat serum, and HE staining was employed to observe the morphology of rat myocardial tissue. RESULTS: The expression of miR-335 in myocardial infarcted zones and border zones of MI rats decreased significantly. The upregulation of miR-335 remarkably inhibited myocardial inflammation and apoptosis after MI, thus improving the cardiac function of MI rats. Compared with the sham group, the MAP3K2 expression in the MI + NC group was observably increased, while the overexpression of miR-335 could inhibit the expression of this protein. Through the Luciferase reporter gene experiment, we found that miR-335 could directly target MAP3K2. CONCLUSIONS: The expression of miR-335 decreased in myocardial tissue after MI, and the overexpression of miR-335 reduced myocardial damage by inhibiting oxidative stress, inflammation, and apoptosis via targeting MAP3K2, thereby improving the cardiac function of MI rats.

[Clinical characteristics and drug susceptibility test of nontuberculous mycobacterial lung disease].

Objective: To investigate the clinical characteristics and drug susceptibility test (DST) of patients infected with different nontuberculous mycobacteria (NTM). Methods: The patients with nontuberculous mycobacterial lung disease (NMLD) in Shanghai Pulmonary Hospital from March 2014 to March 2015 were studied retrospectively by analyzing the clinical characteristics, radiological features and DST results. A total of 201 NMLD patients [male 108, age(58±15) yrs] were enrolled into this study including 48 cases of M. Kansasii [male 13, age (52±16) yrs],46 cases of M. Abscess[male 46, age (57±16) yrs], 92 cases of M. Intracellulare [male 43, age (61±13) yrs], and 15 cases of M. Avium [male 6, age (67±10) yrs]. Clinical data were collected when the diagnosis was made and Chi-square test was used to compare the differences among 4 groups of patients. Bonferroni method was used for further pairwise comparisons. Results: There were significant differences among the 4 groups in the age(χ(2)=6.42, P<0.001) and the gender(χ(2)=49.18, P<0.001) of the patients. The history of bronchiectasis in the groups of M. Kansasii, M. Abscess, M. Intracellulare and M. Avium were 2/48, 31/46, 39/92 and 4/15 cases respectively(χ(2)=41.84, P<0.001). For the Gamma-interferon release assays (ELISA) (IGRA), the positive rate of IGRA in the groups of M. Kansasii, M. Abscess, M. Intracellulare and M. Avium were 83%(40/48), 30%(14/46), 23%(21/92) and 33% (5/15) respectively(χ(2)=50.96, P<0.001). The radiological features were significantly different in tree-in-bud(8/48, 35/46, 36/92 and 4/15 cases respectively, χ(2)=36.48, P<0.001), pleural thickness or mild effusion (21/48, 36/46, 69/92 and 7/15 cases, χ(2)=19.54, P<0.001), bronchiectasis (20/48, 39/46, 78/92 and 10/15 cases, P<0.001) and cavities (38/48, 21/46, 63/92 and 10/15 cases, χ(2)=12.38, P<0.001) among the 4 groups(M. Kansasii, M. Abscess, M. Intracellulare and M. Avium). The drug resistance rates of M. Kansasii to rifampin, ethambutanol and ofloxacin were 10%(5/48), 8%(4/48) and 15%(7/48) respectively; the resistance rates of M.Intracellulare to ethambutanol was 45%(41/92), and the resistance rates of M.Abscess were all over 80% to all anti-TB drugs. The results of pairwise comparisons showed that the male proportion(46/48) and IGRAs positive rate(40/48) of patients with M. Kansasii were higher than those of other groups, and the incidence of bronchiectasis(20/48) and pleural changes(21/48) was lower than those of other groups. The female ratio(33/46), history of bronchiectasis (31/46) and tree-in-bud sign of patients(35/46) with M. Abscess were higher than those of other groups. Conclusions: There were differences in the clinical manifestations and imaging features of 4 common NMLD diseases, which were helpful for clinical differentiation. The patients with M. Kansasii infection were mainly male, with a high IGRA positive rate and fewer lesions of bronchiectasis or pleural changes. Most of the patients with M. Abscess were female, with a previous history of bronchiectasis, and with most of the lesions showing tree-in-bud signs. The NTM species had a high rate of resistance to anti-TB drugs except M. Kansasii.

[The protective effect of the activation of NMDAR1/ERK1/2 signal pathway induced by levodopa on visual cortical neurons in monocular deprivation rats].

Objective: To investigate the protection effects of the activation of NMDAR1(NMDA receptor 1)/ERK1/2 signal pathway on visual cortex nerve cells induced by levodopa in amblyopia rats. Methods: SD rats of SPF grade, were randomly divided into for groups of 9, group A. Control, B. MD group, C. L-levodopa(20 mg·kg(-1))+MD group, D. H-levodopa (80 mg·kg(-1))+MD group, E. H-levodopa+MD+MK801 group, F. H-levodopa+MD+PD98059 group, G. MD+MK801 group, H. MD+PD98059 group, I. MD+DMSO group. Amblyopia rats were made by suture of the right eye. Levodopa was used to treatment amblyopia by gavage, and intervened by intracerebroventricular injection of MK801 and PD98059 respectively. The expression of NR1, p-ERK1/2, ERK1/2, NGF and c-FOS were detected by Western blotting. Nissl staining was used to detect morphological changes of neurons. Neuronal apoptosis was detected by TUNEL method, and detected the expression of Caspase-3, NGF and c-FOS by immunohistochemical staining. One/Two way Chi-square analysis was used for data analysis. LSD-t test was used as comparison between every two groups. Results: The morphology of Nissl bodies in neurons was complete and clear in A group, and the size of Nissl bodies got smaller, and caused karyopyknosis and loss of neurons in visual cortex of B group. Compared with A group, the apoptosis of visual cortical neurons(23.09±2.00 vs. 2.20±0.35, t=12.120, P=0.000) and the number of Caspase-3 postive cells (22.70±1.50 vs. 3.30±0.54, t=12.120, P=0.000)were significantly increased, the expression of NGF(0.31±0.04 vs. 0.74±0.09, t=7.674, P=0.000) and c-FOS(0.25±0.03 vs. 0.57±0.07, t=5.919, P=0.000) and the rats of NGF(8.30±0.82 vs. 35.18±2.01, t=12.37, P=0.0000) and c-FOS (10.84±1.02 vs. 35.68±2.55, t=9.056, P=0.0001) postive cell were decreased significantly in B group. After treatment with levodopa, the morphology of neurons recovered, the apoptosis of visual cortical neurons relieved, the expression of NR1(0.75±0.09 vs. 0.40±0.05, t=8.528, P=0.001) and p-ERK1/2(2.13±0.26 vs. 0.68±0.17, t=3.488, P=0.008) were increased significantly, and the rats of NGF (18.07±0.87 vs. 8.30±0.82, t=8.18, P=0.0000) and c-FOS (19.78±0.91 vs. 10.84±1.02, t=6.543, P=0.0001) postive cells were significantly increased. MK-801 or PD98059 intervention could effectively attenuate the effect of levodopa. It could effectively down-regulated the expression of NR1 (0.53±0.06 vs. 0.95±0.12, t=5.647, P=0.005) and p-ERK1/2(1.52±0.18 vs. 2.58±0.30, t=3.091, P=0.013) interference with MK801 or PD98059 in MD rats. MK-801 or PD98059 intervention further promote the Nissl body volume reduced, neurons karyopyknosis, the apoptosis of visual cortical neurons and Caspase-3 expression, and restrain the expression of NGF and c-FOS. Conclusion: Levodopa played a protective role in visual cortex nerve cells of amblyopia rats at least partially through activation of NMDA-ERK1/2 signal pathway. (Chin J Ophthalmol, 2017, 53: 931-940).

[Expression of AQP-1 and AQP-4 in the Lungs of Drown Rats].

OBJECTIVES: To observe the changes of expression of aquaporin-1（AQP-1） and AQP-4 in drowned and postmortem immersed rats' lungs. METHODS: Thirty healthy male Wistar rats were randomly divided into drowning group, postmortem immersion group and cervical dislocation group. The morphological changes of rats' lungs were observed using HE staining. The mRNA and protein expressions of AQP-1 and AQP-4 in rats' lungs were detected by real-time PCR, immunohistochemistry and Western blotting, respectively. RESULTS: The results of immunohistochemistry and the Western blotting showed that the protein expression of AQP-1 of the drowning group was higher than the postmortem immersion group and the cervical dislocation group （P<0.05）. The result of immunohistochemistry showed that the protein expression of AQP-4 of the drowning group was higher than the postmortem immersion group and the cervical dislocation group （P<0.05） while no difference were detected among the three of them by Western blotting （P>0.05）. The mRNA expressions of AQP-1 and AQP-4 in rats' lungs of the drowning group was significantly higher than the postmortem immersion group （P<0.05）. CONCLUSIONS: The increase of mRNA and protein expressions of AQP-1 and AQP-4 in lungs of rats with cute lung injury of the drowning group would be useful for differentiating vital drowning from postmortem immersion.

The mediating role of cPLA2 in IL-1 beta and IL-6 release in LPS-induced HeLa cells.

Studies were conducted to characterize a HeLa cell model by which the roles of the 85-kDa phospholipase A2 (cPLA2) in interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) release could be evaluated. At first, untreated HeLa cells were compared with lipopolysaccharide (LPS)-treated HeLa cells. The latter resulted in cPLA2 overexpression and an increased trend of IL-1 beta and IL-6 release. The indicated doses of 85-kDa cPLA2 antisense oligonucleotide directed against the initiation site were then used to block cPLA2 in LPS-induced HeLa cells. The process led to a dose-dependent decrease in cPLA2 protein with no noticeable change of cPLA2 mRNA. Compared with that of LPS added only, a reduction of IL-1 beta and IL-6 levels in the supernatants of transfected cells following the repression of cPLA2 was observed. These results suggested that 85-kDa cPLA2 may mediate the signalling cascades by which IL-1 beta and IL-6 were released in LPS-induced HeLa cells.

[Tumor necrosis factor induced enhancement of neutrophil chemotaxis and adhesion through mediating of phospholipase A2 activation].

Recent studies indicate that phospholipase A2 (PLA2) derived lipid mediators regulate a number of neutrophil responses such as chemotaxis, adhesion and degranulation. Since tumor necrosis factor (TNF) is also a key mediator in neutrophil activation, it remains to be shown that PLA2 is involved in the process of TNF activation. Our results shown that TNF (100 ng/ml) given in vitro for 60 min, causes an obvious enhancement of neutrophil chemotaxis towards FMLP, and increased activity of adhesion to glass beads by stimulated release of TXB2 from PMN other than 6-keto-PGF1a. Similar neutrophil activation responses could also be promoted by in vitro addition of arachidonic acid (1 mumol/ml) for 60 min. It was further found that PLA2 inhibitor, 4-bromophencyl bromide (5 mumol/ml), greatly inhibite the TNF induced responces, while cycloxgenase inhibitor indomethathin (85 nmol/ml) was without effect on the activation of TNF. Those results indicated that PLA2 activation was involved in the TNF stimulated enhancement of neutrophil chemotaxis and adhesion.