Involvement of RAGE, MAPK and NF-κB pathways in AGEs-induced MMP-9 activation in HaCaT keratinocytes.
Advanced glycation end products (AGEs) exert divergent effects on the pathogenesis of diabetes complications. Excessive expression of matrix metalloproteinases-9 (MMP-9) is deleterious to the cutaneous wound-healing process in the context of diabetes. However, the effect of AGEs on MMP-9 induction in skin cells and the exact molecular mechanisms involved are still poorly understood. In this study, we investigated the effect of AGEs on the production of MMP-9 in HaCaT keratinocytes and characterized the signal transduction pathways activated by AGEs that are involved in MMP-9 regulation. We showed that AGE-BSA increased MMP-9 expression in HaCaT cells at both the protein and mRNA levels. The stimulatory effect of AGE-BSA on MMP-9 was attenuated by inhibitors of extracellular-signal-regulated kinase (ERK1/2, U0126), p38 mitogen-activated protein kinase (MAPK, SB203580) and NF-κB, but not c-Jun N-terminal kinase. Furthermore, receptor for advanced glycation end products (RAGE) was expressed in keratinocytes, and incubation with AGE-BSA resulted in a significant upregulation of RAGE expression in a dose-dependent manner. Silencing of the RAGE gene prevented AGE-BSA-induced MMP-9 activation and the phosphorylation of ERK1/2 and p38 MAPK. We also observed the involvement of NF-κB in AGE-BSA-induced MMP-9 activation, which was not blocked by U0126 and SB203580. These results suggest that AGEs may play an important role in the impairment of diabetic wound healing by upregulating MMP-9 expression in keratinocytes via the RAGE, ERK1/2 and p38 MAPK pathways; activation of NF-κB is also involved in this process. These pathways may represent potential targets for drug interventions to improve diabetic wound healing, a process in which MMP-9 plays a critical role.
Department of Endocrinology, Guangzhou Red Cross Hospital, The Fourth Affiliated Hospital, Ji'nan University, Guangzhou, China.
Ping
P
Zhu
Meng
M
Ren
Chuan
C
Yang
Yong-Xuan
YX
Hu
Jian-Min
JM
Ran
Li
L
Yan
D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D002460:Cell Line; D015536:Down-Regulation / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects / Q000235:genetics; D017127:Glycation End Products, Advanced / Q000494:pharmacology*; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology*; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism*; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation / Q000187:drug effects; D034741:RNA, Small Interfering / Q000235:genetics; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000235:genetics / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
D017127:Glycation End Products, Advanced; D020780:Matrix Metalloproteinase 9; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D016328:NF-kappa B; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D034741:RNA, Small Interfering; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D012710:Serum Albumin, Bovine; D019715:Tissue Inhibitor of Metalloproteinase-1; D048051:p38 Mitogen-Activated Protein Kinases; C560822:TIMP1 protein, human; C081628:advanced glycation end products-bovine serum albumin; C535150:MAPK1 protein, human