PMID- 30909920 OWN - NLM STAT- MEDLINE DCOM- 20190726 LR - 20231006 IS - 1476-511X (Electronic) IS - 1476-511X (Linking) VI - 18 IP - 1 DP - 2019 Mar 25 TI - Lipopolysaccharide and palmitic acid synergistically induced MCP-1 production via MAPK-meditated TLR4 signaling pathway in RAW264.7 cells. PG - 71 LID - 10.1186/s12944-019-1017-4 [doi] LID - 71 AB - BACKGROUND: Obesity increases the risk of developing diabetes mellitus. Clinical studies suggest that risk factors like palmitic acid (PA) and lipopolysaccharide (LPS) exist simultaneously in diabetes with obesity. Combination of PA and LPS even at low concentration can induce strong inflammatory reaction. Monocyte chemoattractant protein-1 (MCP-1) is an important inflammatory chemokine related to insulin resistance and type II diabetes. Our previous study using PCR array revealed that LPS and PA synergistically induce MCP-1 mRNA expression in macrophage cells RAW264.7, while the protein expression of MCP-1 in this case was not investigated. Moreover, the underling mechanism in the synergistic effect of MCP-1 expression or production induced by treatment of LPS and PA combination remains unclear. METHODS: Protein secretion of MCP-1 was measured by the enzyme-linked immunosorbent assay (ELISA) and mRNA levels of MCP-1 and Toll-like receptor 4 (TLR4) were measured by real-time PCR. Statistical analysis was conducted using SPSS software. RESULTS: LPS could increase MCP-1 transcription as well as secretion in RAW264.7, and PA amplified this effect obviously. Meanwhile, combination of LPS with PA increased TLR4 mRNA expression while LPS alone or PA alone could not, TLR4 knockdown inhibited MCP-1 transcription/secretion induced by LPS plus PA. Moreover, not NF-kappaB inhibitor but inhibitors of mitogen-activated protein kinase (MAPK) signaling pathways, including c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p38 MAPK were found to block MCP-1 generation stimulated by LPS plus PA. CONCLUSION: LPS and PA synergistically induced MCP-1 secretion in RAW264.7 macrophage cells, in which MCP-1 transcription mediated by MAPK/TLR4 signaling pathways was involved. Combined treatment of PA and LPS in RAW264.7 cells mimics the situation of diabetes with obesity that has higher level of PA and LPS, MAPK/TLR4/ MCP-1 might be potential therapeutic targets for diabetes with obesity. FAU - Wang, Xuehong AU - Wang X AD - Department of Pathology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China. AD - Department of Pathology, the Affiliated Hospital of Guilin Medical University, 15 Lequn Road, Guilin, 541001, Guangxi, China. AD - Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, 15 Lequn Road, Guilin, 541001, Guangxi, China. FAU - Jiang, Xin AU - Jiang X AD - Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, 15 Lequn Road, Guilin, 541001, Guangxi, China. AD - China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China. FAU - Deng, Bin AU - Deng B AD - Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, 15 Lequn Road, Guilin, 541001, Guangxi, China. AD - China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China. FAU - Xiao, Juan AU - Xiao J AD - Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, 15 Lequn Road, Guilin, 541001, Guangxi, China. AD - China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China. AD - Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Guilin, 541001, Guangxi, China. FAU - Jin, Junfei AU - Jin J AD - Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, 15 Lequn Road, Guilin, 541001, Guangxi, China. changliangzijin@163.com. AD - China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China. changliangzijin@163.com. AD - Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Guilin, 541001, Guangxi, China. changliangzijin@163.com. FAU - Huang, Zhaoquan AU - Huang Z AD - Department of Pathology, the Affiliated Hospital of Guilin Medical University, 15 Lequn Road, Guilin, 541001, Guangxi, China. gxlzzq@163.com. LA - eng GR - 8156130230/National Natural Science Foundation of China/ GR - 2015GXNSFEA139003/Natural Science Foundation of Guangxi/ PT - Journal Article DEP - 20190325 PL - England TA - Lipids Health Dis JT - Lipids in health and disease JID - 101147696 RN - 0 (Ccl2 protein, mouse) RN - 0 (Chemokine CCL2) RN - 0 (Lipopolysaccharides) RN - 0 (Tlr4 protein, mouse) RN - 0 (Toll-Like Receptor 4) RN - 2V16EO95H1 (Palmitic Acid) RN - EC 2.7.12.2 (MAP Kinase Kinase 1) MH - Animals MH - Chemokine CCL2/*genetics MH - Diabetes Mellitus/drug therapy/genetics/pathology MH - Disease Models, Animal MH - Drug Synergism MH - Gene Expression Regulation/genetics MH - Humans MH - Lipopolysaccharides/*pharmacology MH - MAP Kinase Kinase 1/*genetics MH - Mice MH - Obesity/drug therapy/genetics/pathology MH - Palmitic Acid/*pharmacology MH - RAW 264.7 Cells MH - Signal Transduction/drug effects MH - Toll-Like Receptor 4/*genetics/metabolism PMC - PMC6434618 OTO - NOTNLM OT - Lipopolysaccharide OT - MAPK OT - MCP-1 OT - Palmitic acid OT - TLR4 COIS- ETHICS APPROVAL AND CONSENT TO PARTICIPATE: Not applicable. CONSENT FOR PUBLICATION: Not applicable. COMPETING INTERESTS: The authors have no conflicts of interest to declare. PUBLISHER'S NOTE: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. EDAT- 2019/03/27 06:00 MHDA- 2019/07/28 06:00 PMCR- 2019/03/25 CRDT- 2019/03/27 06:00 PHST- 2018/10/30 00:00 [received] PHST- 2019/03/14 00:00 [accepted] PHST- 2019/03/27 06:00 [entrez] PHST- 2019/03/27 06:00 [pubmed] PHST- 2019/07/28 06:00 [medline] PHST- 2019/03/25 00:00 [pmc-release] AID - 10.1186/s12944-019-1017-4 [pii] AID - 1017 [pii] AID - 10.1186/s12944-019-1017-4 [doi] PST - epublish SO - Lipids Health Dis. 2019 Mar 25;18(1):71. doi: 10.1186/s12944-019-1017-4.