Effect and mechanism of amphiregulin on acute respiratory distress syndrome in mice / 中华危重病急救医学

OBJECTIVE@#To explore the protective effect of amphiregulin (Areg) on acute respiratory distress syndrome (ARDS) in mice and its underlying mechanism.@*METHODS@#(1) Male C57BL/6 mice aged 6-8 weeks were selected for animal experiments and divided into 3 groups (n = 10) according to the random number table method, which includes sham-operated group (Sham group), ARDS model group [ARDS model in mice was established by intratracheal instillation of lipopolysaccharide (LPS) 3 mg/kg] and ARDS+Areg intervention group [recombinant mice Areg (rmAreg) 5 μg was injected intraperitoneally 1 hour after LPS modeling]. The mice were sacrificed at 24 h after LPS injection lung histopathological changes were observed under hematoxylin-eosin (HE) staining and scored for lung injury; oxygenation index and wet/dry ratio of lung tissue were measured; the content of protein in bronchoalveolar lavage fluid (BALF) was detected by bicinchoninic acid (BCA) method, the level of inflammatory factors interleukins (IL-1β, IL-6) and tumor necrosis factor-α (TNF-α) in BALF were measured by enzyme-linked immunosorbent assay (ELISA). (2) Mice alveolar epithelial cell line MLE12 cells were obtained and cultured for experiment in vitro. Blank control group (Control group), LPS group (LPS 1 mg/L) and LPS+Areg group (rmAreg 50 μg/L was added 1 hour after LPS stimulation) were set. The cells and culture fluid were collected at 24 hours after LPS stimulation, and the apoptosis level of MLE12 cells was detected by flow cytometry; the activation level of phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) and the expressions of apoptosis-related proteins Bcl-2 and Bax in MLE12 cells were detected by Western blotting.@*RESULTS@#(1) Animal experiments: compared with the Sham group, the lung tissue structure of ARDS model group was destroyed, the lung injury score was significantly increased, the oxygenation index was significantly decreased, the wet/dry weight ratio of lung was significantly increased, and the levels of protein and inflammatory factors in BALF were significantly increased. Compared with ARDS model group, lung tissue structure damage was reduced, pulmonary interstitial congestion, edema and inflammatory cell infiltration were significantly reduced, and lung injury score was significantly decreased (scores: 0.467±0.031 vs. 0.690±0.034) in ARDS+Areg intervention group. In addition, oxygenation index in ARDS+Areg intervention group was significantly increased [mmHg (1 mmHg ≈ 0.133 kPa): 380.00±22.36 vs. 154.00±20.74]. Lung wet/dry weight ratio (5.40±0.26 vs. 6.63±0.25), protein and inflammatory factors levels in BALF [protein (g/L): 0.42±0.04 vs. 0.86±0.05, IL-1β (ng/L): 30.00±2.00 vs. 40.00±3.65, IL-6 (ng/L): 190.00±20.30 vs. 581.30±45.76, TNF-α (ng/L): 30.00±3.65 vs. 77.00±4.16], and the differences were statistically significant (all P < 0.01). (2) Cell experiments: compared with the Control group, the number of apoptotic MLE12 cells was significantly increased in the LPS group, and the levels of PI3K phosphorylation, anti-apoptotic gene Bcl-2 level and pro-apoptotic gene Bax level were increased in MLE12 cells. Compared with the LPS group, the number of apoptosis in MLE12 cells was significantly reduced in the LPS+Areg group after administration of rmAreg treatment [(17.51±2.12)% vs. (36.35±2.84)%], and the levels of PI3K/AKT phosphorylation and Bcl-2 expression in MLE12 cells were significantly increased (p-PI3K/PI3K: 2.400±0.200 vs. 0.550±0.066, p-AKT/AKT: 1.647±0.103 vs. 0.573±0.101, Bcl-2/GAPDH: 0.773±0.061 vs. 0.343±0.071), and Bax expression was significantly suppressed (Bax/GAPDH: 0.810±0.095 vs. 2.400±0.200). The differences were statistically significant (all P < 0.01).@*CONCLUSIONS@#Areg could alleviate ARDS in mice by inhibiting the apoptosis of alveolar epithelial cells through activating PI3K/AKT pathway.

Expression of amphiregulin in enchondromas and central chondrosarcomas

OBJECTIVES: The aim of this study was to evaluate the role of amphiregulin protein, an epidermal growth factor receptor ligand, in cartilaginous tumors. METHODS: Amphiregulin expression was examined in 31 enchondromas and 67 chondrosarcomas using immunohistochemistry analysis. RESULTS: Overall, 15 enchondromas (48.40%) and 24 chondrosarcomas (35.82%) were positive for amphiregulin. According to the receiver operating characteristic curve test, no difference in amphiregulin expression was observed between enchondromas and low-grade chondrosarcomas (p=0.0880). Additionally, 39 lesions (16 in short bones, 13 in long bones, and 10 in flat bones) were positive for amphiregulin, exhibiting a higher percentage of positive cells (p=0.0030) and intensity of immunohistochemical expression (p=0.0055) in short bone lesions than in others. Among 25 enchondromas localized in short bones, 15 expressed amphiregulin; however, all 6 cases localized in long bones were negative for this marker (p=0.0177). CONCLUSIONS: Amphiregulin did not help in distinguishing enchondromas from low-grade chondrosarcomas. The present study is the first to document the expression of this immunohistochemical marker in enchondromas. Furthermore, amphiregulin expression in enchondromas was localized in short bones, indicating a phenotypic distinction from that in long bones. This distinction may contribute to an improved understanding of the pathogenesis of these lesions.

Mechanism of psoriasis generation in animal models / 药学学报

Psoriasis is a chronic inflammatory disease related to genome-wide and surroundings, it is important to develop a suitable animal model to research psoriasis pathogenesis and evolve pharmacotherapeutics. With the development of transgenetic technology in the past few years, psoriasis virulence gene animal model become a hotspot. Research of animal model of human psoriasis genes is reviewed in the paper.

Upregulation of epidermal growth factor receptor 4 in oral leukoplakia / 国际口腔科学杂志·英文版

In the present study, we investigate the expression profile of the epidermal growth factor receptor family, which comprises EGFR/ErbB1, HER2/ErbB2, HER3/ErbB3 and HER4/ErbB4 in oral leukoplakia (LP). The expression of four epidermal growth factor receptor (EGFR) family genes and their ligands were measured in LP tissues from 14 patients and compared with levels in 10 patients with oral lichen planus (OLP) and normal oral mucosa (NOM) from 14 healthy donors by real-time polymerase chain reaction (PCR) and immunohistochemistry. Synchronous mRNA coexpression of ErbB1, ErbB2, ErbB3 and ErbB4 was detected in LP lesions. Out of the receptors, only ErbB4 mRNA and protein was more highly expressed in LP compared with NOM tissues. These were strongly expressed by epithelial keratinocytes in LP lesions, as shown by immunohistochemistry. Regarding the ligands, the mRNA of Neuregulin2 and 4 were more highly expressed in OLP compared with NOM tissues. Therefore, enhanced ErbB4 on the keratinocytes and synchronous modulation of EGFR family genes may contribute to the pathogenesis and carcinogenesis of LP.

Amphiregulin antisense RNA expression inhibits angiogenesis of human breast cancer in nude mice / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the anti-angiogenic effect of amphiregulin (AR) antisense RNA expression in breast cancer.</p><p><b>METHODS</b>Human AR cDNA antisense plasmid was transfected into NS2T2A1 cells (a human breast cancer cell line). Two selected clones expressed AR antisense RNA (AR AS1 and AR AS3 cell lines) in which AR protein expression was reduced. Control cell line NS2T2A1 V was obtained by empty vector transfection. These cells were injected subcutaneously into nude mice. The effects of conditioned media on proliferation of human microvascular endothelial cells (HMEC) were evaluated and VEGF secreted by the cells was measured by ELISA method. In tumor tissues, VEGF expression levels were measured by quantitative RT-PCR, and CD31-immunostaining was used for intra-tumoral vascular quantification.</p><p><b>RESULTS</b>The proliferation index of HMEC cells grown in conditioned media with AR AS1 and AR AS3 was significantly reduced in comparison with that of control cells, accompanied by a decreased VEGF secretion. In tumors derived from AR AS1 and AR AS3 cells, intra-tumoral vascularization was reduced to about 50% of that derived from control cell line, accompanied with a decrease of VEGF expression.</p><p><b>CONCLUSION</b>Amphiregulin antisense RNA expression inhibits efficiently the angiogenesis in breast cancer, suggesting this growth factor could represent a novel therapeutic target in breast cancer.</p>