Exendin-4 ameliorates oxidized-LDL-induced inhibition of macrophage migration in vitro via the NF-κB pathway

Abstract

Aim: To investigate the effects of the glucagon-like peptide-1 (GLP-1) receptor agonist exendin-4 on oxidized low-density lipoprotein (ox-LDL)-induced inhibition of macrophage migration and the mechanisms underlying the effects of exendin-4. Methods: Primary peritoneal macrophages were extracted from the peritoneal cavity of mice treated with 3% thioglycollate (2 mL, ip). Migration of the macrophages was examined using a cell migration assay. Macrophage migration-related factors including leptin-like ox-LDL receptor (LOX-1), cyclooxygenase 2 (COX-2), tumor necrosis factor (TNF)-α, interleukin-1 (IL-1)β, matrix metalloproteinase-2 (MMP-2), intercellular adhesion molecule (ICAM)-1 and macrophage migration inhibitory factor (MIF) were measured using semiquantitative RT-PCR. Expression of MIF and ICAM-1 proteins was examined with ELISA. Gelatin zymography was used to evaluate the activity of MMP-9. Activation of the NF-κB pathway was determined by confocal laser scanning microscopy. Results: Treatment of the macrophages with ox-LDL (50 μg/mL) markedly suppressed the macrophage migration. Furthermore, ox-LDL treatment substantially increased the expression of the macrophage migration-related factors, the activity of MMP-9 and the translocation of the NF-κB p65 subunit. These effects of ox-LDL were significantly ameliorated by pretreatment with the specific NF-κB inhibitor ammonium pyrrolidine dithiocarbamate (100 μmol/L). These effects of ox-LDL were also significantly ameliorated by pretreatment with exendin-4 (25 and 50 nmol/L). Conclusion: Exendin-4 ameliorates the inhibition of ox-LDL on macrophage migration in vitro, via suppressing ox-LDL-induced expression of ICAM-1 and MIF, which is probably mediated by the NF-κB pathway.

Protective Effects of Glucagon-like Peptide 1 on Endothelial Function in Hypertension

“…110 COX-2 inhibitors and ROS scavengers diminish EDCs in arteries from Ang II-infused mice and SHR. 40 GLP-1 and its analogues have been shown to reduce ROS production [111][112][113][114] and COX-2 expression 40,90,115 in several studies. A highly selective DPP-4 inhibitor sitagliptin attenuates EDCs in arteries of hypertensive rats through elevating the expression of UCP2 and subsequently scavenging mitochondrial ROS, which in turn downregulates COX-2 expression via stimulation of the GLP-1/GLP-1R/AMPKa cascade.…”

Epigenetic upregulation of alpha-synuclein in the rats exposed to methamphetamine

“…ELISA study was performed with commercial ELISA kits to detect the content of α-synuclein (Millipore), IL-1β and TNF-α (R & D Systems) in the substantia nigra as previously reported (Ma et al, 2013). The substantia nigra tissues from the rats in all groups were collected, and processed with commercial ELISA kits following the instructions provided by the manufacturer.…”

Microvesicles shed from bortezomib-treated or lenalidomide-treated human myeloma cells inhibit angiogenesis in�vitro

“…Immunofluorescent (IF) measurement of NF-κB. HUVECs were seeded on climbing slices in 24-well plates and co-cultured with the 5 groups of MM MVs or PBS for 24 h. To measure the effect of NF-κB activation, an NF-κB Activation Nuclear Translocation assay kit (Beyotime Biotech, Haimen, China) was used according to the manufacturer's protocol and a previous study (25). Nuclei (blue) and NF-κB (red) were viewed with a fluorescence-equipped microscope (BX51, Olympus, Tokyo, Japan).…”