Nicorandil protects H9 c2 cardiac cells against high glucose-induced injury and inflammation / 中国药理学通报

Aim To investigate whether nicorandil (Nic)protects H9c2 cardiac cells against high glucose (HG)-induced injury and inflammation by inhibiting nuclear factor-κB (NF-κB )/cyclooxygenase-2 (COX-2 )pathway.Methods Cell viability was measured by cell counter kit-8 (CCK-8)assay.The expression lev-els of NF-κB,COX-2 and cleaved caspase-3 were de-termined by Western blot.The activity of lactate dehy-drogenase (LDH)in the culture medium was measured with commercial kits.The intracellular level of reactive oxygen species (ROS)was detected by 2′,7′-dichlor-fluorescein-diacetate (DCFH-DA)staining followed by photofluorography.The number of apoptotic cells was observed by Hoechst 33258 nuclear staining followed by photofluorography.Mitochondrial membrane poten-tial (MMP)was examined by rhodamine 123 staining followed by photofluorography.The secretion levels of interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) were detected by ELISA.Results After H9 c2 cardiac cells were treated with 35 mmol · L-1 glucose (high glucose,HG)for 24 h,the cell viability was significantly decreased .Pre-treatment of the cells with 20~100 μmol·L-1 Nic for 60 min or 50 μmol· L-1 Nic for 30~120 min before exposure to HG signif-icantly attenuated the decrease in viability induced by HG.On the other hand,HG increased the expression levels of phosphorated (p)-NF-κB p65 and cyclooxy-genase-2 (COX-2 )in H9c2 cardiac cells.Pre-treat-ment of the cells with 50 μmol·L-1 Nic for 60 min at-tenuated the up-regulation of p-NF-κB p65 and COX-2 expression levels induced by HG.Furthermore,HG induced considerable injuries and inflammatory re-sponse,leading to increases in LDH activity,ROS generation,MMP loss,the number of apoptotic cells, the expression of cleaved caspase-3 as well as the se-cretion levels of IL-1βand TNF-α.Pre-treatment of the cells with 50 μmol·L-1 Nic for 60 min before HG exposure,or co-treatment of the cells with 100 μmol· L-1 PDTC (an inhibitor of NF-κB)or 10 μmol·L-1 NS-398 (an inhibitor of COX-2)and HG for 24 h ob-viously reduced the above injuries and inflammatory re-sponse induced by HG. Conclusion Nic protects H9 c2 cardiac cells against HG-induced injury and in-flammation by inhibiting NF-κB/COX-2 pathway.

Inhibitory effect of blocking both epidermal growth factor receptor and cycloox-ygenase-2 pathway on proliferation of lung cancer A549 cells / 中国肿瘤生物治疗杂志

Objective:To explore the inhibitory effects of gefitinib (epidermal growth factor receptor inhibitor) com-bined with celecoxib (cyclooxygenase-2 inhibitor) against human lung cancer A549 cells and the possible mechanism. Methods: A549 cells were cultured in RPMI 1640 medium and were divided into 4 groups: normal control group, 5 μmoL/L gefitinib group, 25 μmol/L celecoxib group, and 5 μ mol/L gefitinib + 25 μmol/L celecoxib group. The morpho-logical changes of A549 cells were observed under inverted microscope 48 h after treatment ; the effects of drugs on growth of A549 Cells were detected by MTT assay; the apoptosis and cell cycles of A549 cells were measured by Annexin V/PI and Hoechst 33258 staining, respectively; and the expression of EGFR protein, COX-2 protein, and EGFR mRNA were determined by immunofluorescenee and real-time PCR. Results: Compared with gefitinib and celecoxib groups, many granules and vacuoles were observed in the gefitinib and celecoxib combination group, and cells became round and there was defluxion. Both gefitinib and celecoxib inhibited the growth of A549 cells in a time- and dose-dependent manner. Af-ter treatment for 48 h, the inhibitory rate was (58.2±4.6) % in the combination group, which was significantly higher than those of the other two groups. Apoptosis rate in the combination group was also significantly higher than those in the other two groups (33.9% vs 6.0%, 8.8%), and the cell proportion in S phase significantly decreased and in G_0/G_1 phases significantly increased(P <0.01). EGFR protein, COX-2 protein, and EGFR mRNA expression in A549 cells was significantly decreased in the combination treatment group compared with those in the other two groups (P < 0.05). Conclusion : Gefitinib and celecoxib can synergistically inhibit the growth of A549 cells, possibly through promoting apop-tosis, G_0/G_1 arrest, and down-regulating activated EGFR and COX-2 expression.

Expression and correlation of COX-2 and VEGF-C in nasopharyngeal carcinoma / 中国耳鼻咽喉头颈外科

OBJECTIVE To investigate vascular endothelial growth factor-C (VEGF-C) and cyclooxyegense-2(COX-2) expression in nasopharyngeal carcinoma. METHODS The expression of COX-2 and VEGF-C were stained respectively in nasopharyngeal carcinoma tissues of 45 patients using immunohistochemical method,and were analyzed with clinical data. RESULTS The positive expression rates of COX-2 and VEGF-C were 68.9 % and 53.3 % respectively in nasopharyngeal carcinoma tissue. The expression of COX-2 was positively correlated with VEGF-C (r=0.334,P