Xu Li1, Yanquan Ma, Tianlu Chen, Jie Tang, Xiaochun Ma. 1. Department of Critical Care Medicine, the First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning, China (Li X, Chen TL, Tang J, Ma XC); Department of Critical Care Medicine, General Hospital of Panjin Oilfield, Panjin 124010, Liaoning, China (Ma YQ). Corresponding author: Ma Xiaochun, Email: xcma2972@sina.com.
Abstract
OBJECTIVE: To determine the effect of unfractionated heparin (UFH) on lipopolysaccharide (LPS)-induced expression of chemokines and nuclear factor-ΚB (NF-ΚB) signaling pathway. METHODS: Human pulmonary microvascular endothelial cells (HPMECs) were cultured in vitro, and the cells between passages 3 and 5 were used in the experiments. The cells were divided into control group, LPS challenge group, 1 kU/L or 10 kU/L UFH+LPS group, and NF-ΚB inhibitor N-tosyl-L-lysyl chloromethyl-ketone (TLCK) group (TLCK+LPS group). HPMECs in LPS challenge group were treated with 10 mg/L LPS. UFH pretreatment with different dosages groups were treated with 1 kU/L or 10 kU/L UFH 15 minutes before LPS challenge. Cells in the TLCK+LPS group were treated with 10 μmol/L of TLCK 30 minutes before the addition of LPS, and HPMECs in control group were treated with an equal volume of phosphate-buffered saline (PBS) instead. The cells were harvested 1 hour after LPS challenge, and the nuclear translocation of NF-ΚB was determined by immunofluorescence assay to detect the effect of UFH on NF-ΚB activation. The levels of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) in cell culture supernatants were determined by enzyme linked immunosorbent assay (ELISA) 3 hours and 6 hours after LPS challenge to detect the effect of UFH on LPS induced expression of chemokines and its mechanism of effect on NF-ΚB signaling pathway in HPMECs. RESULTS: (1) In the control group, NF-ΚB was mostly located in the cytosol as shown by immunofluorescence. Treatment of HPMECs with LPS significantly increased the translocation of NF-ΚB from the cytosol to nucleus. UFH suppressed LPS-induced NF-ΚB activation both in 1 kU/L and 10 kU/L dosages, and 10 kU/L UFH gave even better results. (2) Compared with control group, the levels of IL-8 and MCP-1 in the supernatants in LPS challenge group were significantly increased at 3 hours and 6 hours after LPS challenge [IL-8 (ng/L): 387.1±26.4 vs. 23.8±8.1 at 3 hours, 645.5±69.6 vs. 125.7±18.7 at 6 hours; MCP-1 (ng/L): 3 654.9±467.9 vs. 721.6±61.3 at 3 hours, 8 178.5±792.6 vs. 1 324.7±148.7 at 6 hours, all P < 0.05]. Compared with that of LPS challenge group, in 1 kU/L and 10 kU/L UFH pretreatment groups, the levels of IL-8 and MCP-1 were significantly decreased [IL-8 (ng/L): 315.3±24.8, 275.8±31.1 vs. 387.1±26.4 at 3 hours, 557.8±43.3, 496.9±38.7 vs. 645.5±69.6 at 6 hours; MCP-1 (ng/L): 2 924.1±267.9, 2 668.3±522.6 vs. 3 654.9±467.9 at 3 hours, 7 121.7±557.2, 6 563.9±576.4 vs. 8 178.5±792.6 at 6 hours, all P < 0.05]. The results indicated that 10 kU/L UFH yielded better results. However, inhibition study using the known NF-ΚB inhibitor TLCK could decrease LPS-induced increase in IL-8 and MCP-1 levels [IL-8 (ng/L): 162.4±21.3 vs. 387.1±26.4 at 3 hours, 274.1±22.6 vs. 645.5±69.6 at 6 hours; MCP-1 (ng/L): 1 478.2±138.5 vs. 3 654.9±467.9 at 3 hours; 3 667.6±259.4 vs. 8 178.5±792.6 at 6 hours, all P < 0.05]. CONCLUSIONS: The levels of IL-8 and MCP-1 were increased obviously in LPS treated HPMECs. UFH might suppress LPS-activated NF-ΚB signaling pathway, contributing to the inhibitory effects of chemokines in HPMECs.
OBJECTIVE: To determine the effect of unfractionated heparin (UFH) on lipopolysaccharide (LPS)-induced expression of chemokines and nuclear factor-ΚB (NF-ΚB) signaling pathway. METHODS:Human pulmonary microvascular endothelial cells (HPMECs) were cultured in vitro, and the cells between passages 3 and 5 were used in the experiments. The cells were divided into control group, LPS challenge group, 1 kU/L or 10 kU/L UFH+LPS group, and NF-ΚB inhibitor N-tosyl-L-lysyl chloromethyl-ketone (TLCK) group (TLCK+LPS group). HPMECs in LPS challenge group were treated with 10 mg/L LPS. UFH pretreatment with different dosages groups were treated with 1 kU/L or 10 kU/L UFH 15 minutes before LPS challenge. Cells in the TLCK+LPS group were treated with 10 μmol/L of TLCK 30 minutes before the addition of LPS, and HPMECs in control group were treated with an equal volume of phosphate-buffered saline (PBS) instead. The cells were harvested 1 hour after LPS challenge, and the nuclear translocation of NF-ΚB was determined by immunofluorescence assay to detect the effect of UFH on NF-ΚB activation. The levels of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) in cell culture supernatants were determined by enzyme linked immunosorbent assay (ELISA) 3 hours and 6 hours after LPS challenge to detect the effect of UFH on LPS induced expression of chemokines and its mechanism of effect on NF-ΚB signaling pathway in HPMECs. RESULTS: (1) In the control group, NF-ΚB was mostly located in the cytosol as shown by immunofluorescence. Treatment of HPMECs with LPS significantly increased the translocation of NF-ΚB from the cytosol to nucleus. UFH suppressed LPS-induced NF-ΚB activation both in 1 kU/L and 10 kU/L dosages, and 10 kU/L UFH gave even better results. (2) Compared with control group, the levels of IL-8 and MCP-1 in the supernatants in LPS challenge group were significantly increased at 3 hours and 6 hours after LPS challenge [IL-8 (ng/L): 387.1±26.4 vs. 23.8±8.1 at 3 hours, 645.5±69.6 vs. 125.7±18.7 at 6 hours; MCP-1 (ng/L): 3 654.9±467.9 vs. 721.6±61.3 at 3 hours, 8 178.5±792.6 vs. 1 324.7±148.7 at 6 hours, all P < 0.05]. Compared with that of LPS challenge group, in 1 kU/L and 10 kU/L UFH pretreatment groups, the levels of IL-8 and MCP-1 were significantly decreased [IL-8 (ng/L): 315.3±24.8, 275.8±31.1 vs. 387.1±26.4 at 3 hours, 557.8±43.3, 496.9±38.7 vs. 645.5±69.6 at 6 hours; MCP-1 (ng/L): 2 924.1±267.9, 2 668.3±522.6 vs. 3 654.9±467.9 at 3 hours, 7 121.7±557.2, 6 563.9±576.4 vs. 8 178.5±792.6 at 6 hours, all P < 0.05]. The results indicated that 10 kU/L UFH yielded better results. However, inhibition study using the known NF-ΚB inhibitor TLCK could decrease LPS-induced increase in IL-8 and MCP-1 levels [IL-8 (ng/L): 162.4±21.3 vs. 387.1±26.4 at 3 hours, 274.1±22.6 vs. 645.5±69.6 at 6 hours; MCP-1 (ng/L): 1 478.2±138.5 vs. 3 654.9±467.9 at 3 hours; 3 667.6±259.4 vs. 8 178.5±792.6 at 6 hours, all P < 0.05]. CONCLUSIONS: The levels of IL-8 and MCP-1 were increased obviously in LPS treated HPMECs. UFH might suppress LPS-activated NF-ΚB signaling pathway, contributing to the inhibitory effects of chemokines in HPMECs.
Authors: Juan A Siordia; Michael Bernaba; Kenji Yoshino; Abid Ulhaque; Sooraj Kumar; Mario Bernaba; Edward Bergin Journal: SN Compr Clin Med Date: 2020-07-15