[Chrysin inhibited epithelial-mesenchymal transition of type â ¡ alveolar epithelial cell by regulating NF-κB/Twist 1 signaling pathway].

This study aimed to assess whether chrysin(ChR) can inhibit epithelial-mesenchymal transition(EMT) of type Ⅱ alveolar epithelial cell and produce anti-pulmonary fibrosis effect by regulating the NF-κB/Twist 1 signaling pathway. Sixty rats were randomly divided into the control group, the bleomycin(BLC) group, BLC+ChR(50 mg·kg~(-1)) group and BLC+ChR(100 mg·kg~(-1)) group, with 15 rats in each group. The pulmonary fibrosis model was induced by intratracheal injection of BLC(7 500 U·kg~(-1)). Rats were orally administered with different doses of ChR after BLC injection for 28 days. The cells were divided into control group, TGF-ß1 group(5 ng·mL~(-1)), and TGF-ß1+ChR(1, 10, 100 µmol·L~(-1)) groups. The type Ⅱ alveolar epithelial cells were treated with TGF-ß1 for 24 h, and then treated with TGF-ß1 for 48 h in the presence or absence of different doses of ChR(1, 10 and 100 µmol·L~(-1)). The morphological changes and collagen deposition in lung tissues were analyzed by HE staining, Masson staining and immunohistochemistry. The mRNA and protein expression levels of collagen Ⅰ, E-cadherin, zonula occludens-1(ZO-1), vimentin, alpha smooth muscle actin(α-SMA), inhibitor of nuclear factor kappa B alpha(IκBα), nuclear factor-kappa B p65(NF-κB p65), phospho-NF-κB p65(p-p65) and Twist 1 in lung tissues and cells were detected by qPCR and Western blot, respectively. The animal experiment results showed that as compared with the BLC group, after administration of ChR for 28 days, bleomycin-induced pulmonary fibrosis in rats was significantly relieved, collagen Ⅰ expression in lung tissues was significantly reduced(P<0.05 or P<0.01), and EMT of alveolar epithelial cells was obviously inhibited [the expression levels of E-cadherin and ZO-1 were increased and the expression levels of vimentin and α-SMA were decreased(P<0.05 or P<0.01)], concomitantly with significantly reduced IκBα and p65 phosphorylation level in cytoplasm and decreased NF-κB p65 and Twist 1 expression in nucleus(P<0.05 or P<0.01). The cell experiment results showed that different doses of ChR(1, 10 and 100 µmol·L~(-1)) significantly reduced TGF-ß1-induced collagen Ⅰ expression(P<0.05 or P<0.01), significantly inhibited EMT of type Ⅱ alveolar epithelial cells[the expression levels of E-cadherin and ZO-1 were increased and the expression levels of vimentin and α-SMA were decreased(P<0.05 or P<0.01)], and inhibited IκBα and p65 phosphorylation in cytoplasm and down-regulated NF-κB p65 and Twist 1 expression in nucleus induced by TGF-ß1(P<0.05 or P<0.01). The results suggest that ChR can reverse EMT of type Ⅱ alveolar epithelial cell and alleviate pulmonary fibrosis in rats, and its mechanism may be associated with reducing IκBα phosphorylation and inhibiting NF-κB p65 phosphorylation and nuclear transfer, thus down-regulating Twist 1 expression.

Decarbromodiphenyl ether (BDE-209) promotes monocyte-endothelial adhesion in cultured human aortic endothelial cells through upregulating intercellular adhesion molecule-1.

There is growing evidence that exposure to persistent organic pollutants (POPs) is statistically associated with incidence of cardiovascular disease (CVD) or its risk factors. Decarbromodiphenyl ether (BDE-209) is a new POP which exists extensively in human tissues, but its potential effects on CVD have so far received less focus. The adhesion of circulating monocytes to endothelial cells is one of the critical underlying steps in the initiation and development of CVD. In the present study, we investigated the effect of BDE-209 on the adhesion of THP-1 monocytes to human aortic endothelial cells (HAECs) and identified the molecular mechanisms involved. Our results showed that 6.25, 12.5 and 25 µM of BDE-209 exposures caused significant increases in monocyte-endothelial cell adhesion, in a dose-dependent manner. Mechanistically, BDE-209 exposure increased the expression of intercellular adhesion molecule-1 (ICAM-1). Moreover, the up-regulation of ICAM-1 was accompanied by a decrease in the expression of microRNA-141 (miR-141). Furthermore, the up-regulation of ICAM-1 and the increased adhesion induced by BDE-209 could be reversed by miR-141 supplement. Taken together, our results show that BDE-209 potentiates monocyte-endothelial cell interaction via miR-141/ICAM-1 pathway in HAECs.

[Expressions of fractalkine and CD11c on common carotid artery atherosclerotic plaques from apoE(-/-) mice].

OBJECTIVE: To explore the association of fractalkine (FKN) and CD11c expressions oncommon carotid artery atherosclerotic plaques from apoE(-/-) mice with the severity of atherosclerotic lesions. METHODS: Totally 24 apoE(-/-) mice were divided into two groups and fed on a high-fat diet or a normal diet for 12 weeks. Then the blood lipids as well as the plaque area and vascular stenosis rate of the common carotid artery were measured to evaluate the severity of atherosclerotic lesions of the animals. Moreover, immunohistochemical staining was performed to examine the levels of FKN and CD11c expression. RESULTS: The plaque areas and vascular stenosis rates of the common carotid artery in the experimental group were remarkably larger than those in control group (about 4-fold and 2-fold, respectively). The level of FKN expression in the experimental group was 2 times of that in the control group (P<0.05), and the number of CD11c (+) cells in the plaques in the experimental group was about 4 times of than in the control group (P<0.05). CONCLUSION: The expressions of chemokine and FKN remarkably increase in apoE (-/-) atherosclerotic plaques, suggesting that chemokine and FKN may paly important roles in the development of atherosclerosis.

Early genetic diagnosis of clarithromycin resistance in Helicobacter pylori.

BACKGROUND: The drug resistance rate of clinical Helicobacter pylori (H. pylori) isolates has increased. However, the mechanism of drug resistance remains unclear. In this study, drug-resistant H. pylori strains were isolated from different areas and different populations of Chinese for genomic analysis. AIM: To investigate drug-resistant genes in H. pylori and find the genes for the early diagnosis of clarithromycin resistance. METHODS: Three drug-resistant H. pylori strains were isolated from patients with gastritis in Bama County, China. Minimal inhibitory concentrations of clarithromycin, metronidazole, and levofloxacin were determined and complete genome sequencing was performed with annotation. Hp1181 and hp1184 genes were found in these strains and then detected by reverse transcription polymerase chain reaction. The relationships between hp1181 or hp1184 and clarithromycin resistance were ascertained with gene mutant and drug-resistant strains. The homology of the strains with hp26695 was assessed through complete genome detection and identification. Differences in genome sequences, gene quantity, and gene characteristics were detected amongst the three strains. Prediction and analysis of the function of drug-resistant genes indicated that the RNA expression of hp1181 and hp1184 increased in the three strains, which was the same in the artificially induced clarithromycin-resistant bacteria. After gene knockout, the drug sensitivity of the strains was assessed. RESULTS: The strains showing a high degree of homology with hp26695, hp1181, and hp1184 genes were found in these strains; the expression of the genes hp1184 and hp1181 was associated with clarithromycin resistance. CONCLUSION: Hp1181 and hp1184 mutations may be the earliest and most persistent response to clarithromycin resistance, and they may be the potential target genes for the diagnosis, prevention, and treatment of clarithromycin resistance.

[Effect of small dose capsaicin for treatment of pulmonary fibrosis in mice and its mechanism].

Objective: To observe whether the mechanism of small dose capsaicin (Cap) against pulmonary fibrosis in mouse is mediated by agitating transient receptor potential vanilloid 1 (TRPV1). Methods: A total of 60 BALB/c mice were randomly divided into control (CON) group, bleomycin (BLM)group, Cap (0.5, 1,2 mg/kg) groups and Cap (2 mg/kg) plus SB-452533 (2.5 mg/kg) group. C57BL/6 mice were intratracheally injected with 3.5 mg/kg BLM to induce pulmonary fibrosis model. Animals for drugs treatment received daily drug via subcutaneous injection for 21 days. The morphological changes and collagen deposition in lung tissues were analysed by HE staining, Masson staining and immunohistochemistry. The concentration of calcitonin gene-related peptide (CGRP) in plasma was determined by ELISA. The mRNA and (or) proteins levels of α-CGRP, ß-CGRP, collagen I, collagen III, E-Cadherin, zonula occludens-1 (ZO-1), vimentin, alpha smooth muscle actin (α-SMA), TRPV1, p-ERK1/2 and eukaryotic initiation factor 3a (eIF3a) were detected by qPCR and (or) Western blot. Results: Compared with the BLM group, small dose Cap significantly reduced bleomycin-induced pulmonary fibrosis in mice and obviously reversed alveolar epithelial cells epithelial-mesenchymal transition (EMT) (the expression of E-cadherin and ZO-1 were increased(P＜0.05 or P＜0.01)and the expression of α-SMA and Vimentin were decreased (P＜0.05 or P＜0.01) after drugs treatment for 21 day, concomitantly with the increase the expressions of TRPV1 and CGRP (P＜0.05 or P＜0.01), and inhibiting ERK1/2 phosphorylation and eIF3a expression (P＜0.05 or P＜0.01). These effects of small dose Cap were abolished in the presence of TRPV1 receptor antagonist SB-452533. Conclusion: The results suggest that small dose Cap can reverse alveolar epithelial cells EMT and alleviate bleomycin-induced pulmonary fibrosis in mice by inhibiting ERK1/2/eIF3asignaling pathway, which is related to agitating TRPV1 receptor and releasing of CGRP.

[The pathological observation of acute intoxication by Alangium Chinese in mice].

OBJECTIVE: To investigate the pathological change of mice organ intoxicated by Alangium Chinese and its poisoning mechanism. METHODS: Mice were intoxicated by gavage with extract of Alangium Chinese. Then the histopathologic examination was made for evaluating the pathological changes in the organs of the poisoned mice by HE staining. RESULTS: The main pathological changes included alveolar hemorrhage, pulmonary interstitial hemorrhage, sinus hepaticus expansion and congestion, hepatocyte edema, subarachnoid hemorrhage, congestion and hemorrhage of other organs. CONCLUSION: The main target organs or tissue of Alangium Chinese are the lungs, liver and vascular smooth muscle. There is correlation between the toxic effect and the dosage.

MicroRNA-21 attenuates BDE-209-induced lipid accumulation in THP-1 macrophages by downregulating Toll-like receptor 4 expression.

Growing evidence demonstrates a possible response of specific microRNA (miRNA) to environmental pollutant stimuli in multiple biological processes. We previously reported that a persistent organic pollutant, decabromodiphenyl ether (BDE-209), can enhance Toll-like receptor 4 (TLR4)-dependent lipid uptake in THP-1 macrophages; whether miRNAs are involved in this process remains unclear. In the present study, we investigated the levels of several miRNAs related to TLR4 signaling, including miRs-9, -21, -27b, -125b, -132, -146a, -147, -155, and -let-7e, in THP-1 macrophages after stimulation by BDE-209 and oxidized low-density lipoprotein. The results showed that the levels of miR-21 were significantly suppressed by BDE-209 at concentrations of 6.25, 12.5 and 25 µM, in a dose-dependent manner; whereas there was no significant changes for the other miRNAs investigated. Moreover, the suppression of miR-21 was accompanied by an upregulated TLR4 expression, at both mRNA and protein levels. Further analysis showed that the up-regulated TLR4 induced by BDE-209 was inhibited in macrophages transfected with miR-21 mimic; meanwhile opposite results were exhibited when an anti-miR-21 inhibitor was transfected to the macrophages. Additionally, transfection with miR-21 mimic effectively attenuated BDE-209-induced lipid accumulation in macrophages. Together, these data illustrate that miR-21 inhibits BDE-209-triggered lipid accumulation in macrophages through down-regulating TLR4 expression.

[Correlation between chondrocyte apoptosis of vertebral cartilage endplate and degeneration of intervertebral disc].

OBJECTIVE: To investigate the correlation between chondrocyte apoptosis of cartilage endplate and intervertebral disc degeneration. METHODS: Forty adult New Zealand rabbits were randomized into 2 equal groups: experimental group, undergoing exposure of the upper and lower margins of vertebral bodies C4 and C5, lower ARFIN OF c3, and upper margin of C6, and wadding of bone cement to the depth of posterior margin to interrupt the nutrition supply to the vertebral endplate, thus establishing the models of intervertebral disc degeneration, and control group, only undergoing exposure of the cervical vertebrae. Four and 8 weeks later ten rabbits from each group were sacrificed to obtain specimens of cartilage endplate and tissues of intervertebral disc. TUNEL approach was used to detect the apoptosis of chondrocytes in the vertebral cartilage endplate and immunohistochemistry was used to determine the expression of type II collagen from the intervertebral disc tissues. RESULTS: Four weeks after the operation the number of apoptotic chondrocytes of the cartilage endplate in the experimental group was 9.9 +/- 0.88/HP, significantly higher than that of the control group (9.7 +/- 0.94/HP, P < 0.05). Eight weeks after the operation the number of apoptotic chondrocytes of the cartilage endplate in the experimental group was 12.4 +/- 0.71/HP, significantly higher than that of the control group (11.7 +/- 0.91/HP, P < 0.05). Four and 8 weeks after the operation, the numbers of type II collagen positive cells of the experiment group were 27.7 +/- 1.52/HP and 19.5 +/- 1.57/HP respectively, both significantly lower than those of the control group (29.6 +/- 1.54/HP and 20.6 +/- 1.40/HP respectively, both P < 0.05). Correlation analysis showed that vertebral cartilage endplate chondrocyte apoptosis was highly negatively correlated with the expression of type II collagen operation 4 and 8 weeks after the operation with the coefficient values of 0.86 and 0.82 respectively (both P < 0.05). CONCLUSION: Chondrocyte apoptosis in vertebral cartilage endplate may result in the decreased expression of type II collagen in intervertebral discs and lead to the degeneration of intervertebral discs.

Decabromodiphenyl ether (BDE-209) enhances foam cell formation in human macrophages via augmenting Toll-like receptor 4-dependent lipid uptake.

Growing epidemiological evidence is substantiating an association between exposure to persistent organic pollutants (POPs) and incidence of atherosclerosis. Decabromodiphenyl ether (BDE-209) is a new POP which presents extensively in human populations; whether this contaminant is potentially arteriosclerotic remains unclear. In this study, we investigated the effects of BDE-209 on macrophage-derived foam cell formation, a hallmark of early atherosclerosis, using THP-1-derived macrophages incubated with oxidized low-density lipoprotein (oxLDL) as a foam cell model. The results showed that 6.25, 12.5 and 25.0 µM of BDE-209 significantly enhanced lipid accumulation inside the foam cells, in a dose-dependent manner. Further mechanism assays suggested that BDE-209 significantly increased the expression of Toll-like receptor 4 (TLR4), a signal transducing integral membrane protein mediating lipid uptake in macrophages, at both the mRNA and protein levels. In contrast, there was no significant changes for several key regulators involving in lipid efflux, lipogenesis, and lipid oxidation in macrophages. Furthermore, the augmented lipid accumulation was almost completely abrogated by treatment with an anti-TLR4 antibody. Together, these data illustrate that BDE-209 enhances oxLDL-induced macrophage foam cell formation via augmenting TLR4-dependent lipid uptake in the cells.

Inhibition of NF-κB pathway in fibroblast-like synoviocytes by α-mangostin implicated in protective effects on joints in rats suffering from adjuvant-induced arthritis.

α-Mangostin (MG) is a bioactive compound isolated from mangosteen. This study was aimed to investigate effects of MG on adjuvant-induced arthritis (AA) in rats and decipher the underlying mechanisms. Clinical severity of AA was evaluated by paw oedema, arthritis score, and hematological parameters. Digital radiography (DR) and histological examinations were employed to assess joints destructions. Immune functions were evaluated by T cell subsets distribution. Effects on NF-κB pathway were investigated by immunohistochemical, western-blot and immunofluorescence methods both in vivo and vitro. It was found MG possessed superior anti-inflammatory effects in vivo, suggested by attenuated paw swelling, reduced inflammatory cells infiltration and decreased the secretion of TNF-α and IL-1ß in serum. Meanwhile MG inhibited fibrous hyperplasia, synovial angiogenesis, cartilage and bone degradation in AA rats. Although MG exerted little effects on CD4+ population, it greatly decreased IFN-γ positive cells and promoted expression of FOXP3 in immune organs, indicating restoration of Th1/Treg cells ratio and recovery of immune homeostasis in vivo. Inhibition of NF-κB induced by MG was indicated by reduced the expression of p-p65 and VEGF in synovium. In vitro experiments found MG at 10 µg/ml significantly suppressed the expression and phosphorylation of key proteins implicated in NF-κB pathway and inhibited nucleus translocation of p65. These changes led to increased apoptosis and proliferation inhibition of HFLS-RA cells. The results demonstrated regulation of immune functions was deeply involved in the therapeutic actions of MG on AA, and it's inhibition on NF-κB in fibroblast-like synoviocytes was associated to the protective effects on joints.

Relationship between inactivation of p16 gene and gastric carcinoma.

AIM: To investigate the relationship between inactivation of p16 gene and gastric carcinoma, and the mechanism of inactivation of p16 gene in gastric carcinogenesis. METHODS: 40 fresh tumor tissue specimens were taken from primary gastric cancer patients. Expression of P16 protein was detected by immunohistochemical method. Deletion and point mutation of p16 gene were analyzed by polymerase chain reaction (PCR) and DNA sequencing, respectively. RESULTS: The frequency of loss of P16 protein expression in the gastric cancer tissue, adjacent nontumor tissue, and distal normal tissue was 77.5 % (31/40), 55.0 % (22/40), and 17.5 % (7/40), respectively (P<0.005). Homozygous deletion of exon 1 and exon 3 was observed in two and three cases, respectively, giving an overall frequency of homozygous deletion of 12.5 %. All five cases had diffuse type gastric carcinoma. No p16 gene point mutation was detected. CONCLUSION: These findings suggest a close correlation between inactivation of p16 gene and gastric carcinoma. Further investigations are needed to testify the mechanism of inactivation of p16 gene in gastric carcinogenesis.