Summary: Endothelial dysfunction induced by intermittent hypoxia (IH) participates in obstructive sleep apnea syndrome (OSAS)-associated cardiovascular disorders. Myeloid differentiation primary response 88 (My...Summary: Endothelial dysfunction induced by intermittent hypoxia (IH) participates in obstructive sleep apnea syndrome (OSAS)-associated cardiovascular disorders. Myeloid differentiation primary response 88 (MyD88) and tumor necrosis factor receptor-associated factor 6 (TRAF6) regulate nu- merous downstream adaptors like mitogen-activated protein kinases (MAPKs) and the subsequent oxidative stress and inflammatory responses. This study aimed to characterize the role of MyD88/TRAF6 in IH-treated cell function and its associated signaling. Human umbilical vein endo- thelial cells (HUVECs) were randomly exposed to IH or normoxia for 0, 2, 4 and 6 h. Western blot- ting was used to detect the expression pattern of target gene proteins [angiotensin 1 receptor (AT1R), p-ERK1/2, p-p38MAPK, MyD88 and TRAF6], and the relationships among these target genes down-regulated by the corresponding inhibitors were studied. Finally, the influence of these target genes on proliferation of HUVECs was also assessed by EdU analysis. Protein levels of AT1R, TRAF6 and p-ERK1/2 were increased after IH exposure, with a slight rise in MyD88 and a dynamic change in p-p38MAPK. The down-regulation of TRAF6 by siRNA reduced ERK1/2 phosphorylation during IH without any effects on ATIR. Blockade of AT1R with valsartan decreased TRAF6 and p-ERK1/2 protein expression after IH exposure. ERK1/2 inhibition with PD98059 suppressed only AT1R expression. IH promoted HUVECs proliferation, which was significantly suppressed by the in- hibition of TRAF6, AT1R and ERK1/2. The findings demonstrate that TRAF6 regulates the prolifera- tion of HUVECs exposed to short-term IH by modulating cell signaling involving ERK1/2 down- stream of AT1R. Targeting the AT1R-TRAF6-p-ERK1/2 signaling pathway might be helpful in re- storing endothelial function.展开更多
Summary: Poly (ADP-ribose) polymerase-1 (PARP-1) inhibitors and histone deacetylase (HDAC) in- hibitors have recently emerged as promising anticancer drugs. The aim of this study was to investigate the effect o...Summary: Poly (ADP-ribose) polymerase-1 (PARP-1) inhibitors and histone deacetylase (HDAC) in- hibitors have recently emerged as promising anticancer drugs. The aim of this study was to investigate the effect of combination treatment with the PARP inhibitor P J34 and HDAC inhibitor SAHA on the proliferation of liver cancer cells. Cell proliferation and apoptosis were assessed in three human liver cancer cell lines (HepG2, Hep3B and HCC-LM3) treated with PJ34 (8 μmol/L) and SAHA (1 panol/L), alone or combined, by Cell Counting Kit-8 assay and flow cytometry, respectively. The nude mice bear- ing subcutaneous HepG2 tumors were administered different groups of drugs (10 mg/kg PJ34, 25 mg/kg SAHA, 10 mg/kg PJ34+25 mg/kg SAHA), and the inhibition rates of tumor growth were compared between groups. The results showed that combined use of P J34 and SAHA could synergistically inhibit the proliferation of liver cancer cell lines HepG2, Hep3B and HCC-LM3. The apoptosis rate of HepG2 cells treated with PJ34+SAHA was significantly higher than that of HepG2 cells treated with PJ34 or SAHA alone (P〈0.05). In vivo, the tumor inhibition rates were 53.5%, 61.4% and 82.6% in PJ34, SAHA and PJ34+SAHA groups, respectively. The combined use of PJ34 and SAHA could significantly inhibit the xenograft tumor growth when compared with use of P J34 or SAHA alone (P〈0.05). It was led to conclude that P J34 and SAHA can synergistically suppress the proliferation of liver cancer cells.展开更多
基金supported by grants from the National Natural Science Foundation of China(No.81070067 and No.81370185)
文摘Summary: Endothelial dysfunction induced by intermittent hypoxia (IH) participates in obstructive sleep apnea syndrome (OSAS)-associated cardiovascular disorders. Myeloid differentiation primary response 88 (MyD88) and tumor necrosis factor receptor-associated factor 6 (TRAF6) regulate nu- merous downstream adaptors like mitogen-activated protein kinases (MAPKs) and the subsequent oxidative stress and inflammatory responses. This study aimed to characterize the role of MyD88/TRAF6 in IH-treated cell function and its associated signaling. Human umbilical vein endo- thelial cells (HUVECs) were randomly exposed to IH or normoxia for 0, 2, 4 and 6 h. Western blot- ting was used to detect the expression pattern of target gene proteins [angiotensin 1 receptor (AT1R), p-ERK1/2, p-p38MAPK, MyD88 and TRAF6], and the relationships among these target genes down-regulated by the corresponding inhibitors were studied. Finally, the influence of these target genes on proliferation of HUVECs was also assessed by EdU analysis. Protein levels of AT1R, TRAF6 and p-ERK1/2 were increased after IH exposure, with a slight rise in MyD88 and a dynamic change in p-p38MAPK. The down-regulation of TRAF6 by siRNA reduced ERK1/2 phosphorylation during IH without any effects on ATIR. Blockade of AT1R with valsartan decreased TRAF6 and p-ERK1/2 protein expression after IH exposure. ERK1/2 inhibition with PD98059 suppressed only AT1R expression. IH promoted HUVECs proliferation, which was significantly suppressed by the in- hibition of TRAF6, AT1R and ERK1/2. The findings demonstrate that TRAF6 regulates the prolifera- tion of HUVECs exposed to short-term IH by modulating cell signaling involving ERK1/2 down- stream of AT1R. Targeting the AT1R-TRAF6-p-ERK1/2 signaling pathway might be helpful in re- storing endothelial function.
基金supported by grants from the National Natural Science Foundation of China(No.81172293)the New Century Excellent Talent Foundation of Ministry of Education of China(No.NCET-04-0701)
文摘Summary: Poly (ADP-ribose) polymerase-1 (PARP-1) inhibitors and histone deacetylase (HDAC) in- hibitors have recently emerged as promising anticancer drugs. The aim of this study was to investigate the effect of combination treatment with the PARP inhibitor P J34 and HDAC inhibitor SAHA on the proliferation of liver cancer cells. Cell proliferation and apoptosis were assessed in three human liver cancer cell lines (HepG2, Hep3B and HCC-LM3) treated with PJ34 (8 μmol/L) and SAHA (1 panol/L), alone or combined, by Cell Counting Kit-8 assay and flow cytometry, respectively. The nude mice bear- ing subcutaneous HepG2 tumors were administered different groups of drugs (10 mg/kg PJ34, 25 mg/kg SAHA, 10 mg/kg PJ34+25 mg/kg SAHA), and the inhibition rates of tumor growth were compared between groups. The results showed that combined use of P J34 and SAHA could synergistically inhibit the proliferation of liver cancer cell lines HepG2, Hep3B and HCC-LM3. The apoptosis rate of HepG2 cells treated with PJ34+SAHA was significantly higher than that of HepG2 cells treated with PJ34 or SAHA alone (P〈0.05). In vivo, the tumor inhibition rates were 53.5%, 61.4% and 82.6% in PJ34, SAHA and PJ34+SAHA groups, respectively. The combined use of PJ34 and SAHA could significantly inhibit the xenograft tumor growth when compared with use of P J34 or SAHA alone (P〈0.05). It was led to conclude that P J34 and SAHA can synergistically suppress the proliferation of liver cancer cells.