title: Interleukin-1β increases Angptl4 (FIAF) expression via the JNK signaling pathway in osteoblastic MC3T3-E1 cells.
abstract: Angiopoietin-like protein 4 (Angptl4), also known as fasting-induced adiopogenic factor (FIAF), has recently been reported to influence bone metabolism. However, there have been few studies on regulatory factors other than hypoxia for Angptl4 in bone, and particularly in osteoblasts. Expression of interleukin-1β (IL-1β), a proinflammatory cytokine, is increased in serum or bone microenvironments in inflammatory bone diseases or estrogen deficient-conditions. The present study was conducted to determine whether Angptl4 expression in osteoblasts is affected by IL-1β and investigate its involvement in MAP kinase signaling pathways. Angptl4 RNA levels were increased by IL-1β treatment in murine MC3T3-E1 osteoblastic cells. Western blotting and immunofluorescent staining showed a corresponding increase in Angptl4 protein. IL-1β treatment of osteoblasts induced phosphorylation of mitogen-activated protein kinases (MAPKs) including extracellular regulated kinases (ERKs), p38, and c-Jun N-terminal kinase (JNK). Furthermore, SP600125, an inhibitor of JNK, significantly blocked the upregulation of Angptl4 by IL-1β. In contrast, treatment with an inhibitor of p38 MAP kinase (SB203580) or an ERK inhibitor (PD98059) produced responses similar to those seen with the DMSO control. Taken together, these results suggest that IL-1β increases Angptl4 expression through a mechanism dependent on the JNK-MAPK signaling pathway in MC3T3-E1 cells.
authors.affiliation: Department of Internal Medicine, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University - Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.
authors.forename: J M
authors.initials: JM
authors.lastname: Noh
authors.affiliation: Department of Internal Medicine, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University - Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.
authors.forename: C
authors.initials: C
authors.lastname: Shen
authors.affiliation: Department of Internal Medicine, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University - Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.
authors.forename: S J
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University - Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.
authors.forename: M R
authors.initials: MR
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University - Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.
authors.forename: S H
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Presbyterian Medical Center, Jeonju, Republic of Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Biochemistry, Chonbuk National University Medical School, Jeonju, Republic of Korea.
authors.forename: B H
authors.initials: BH
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University - Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Republic of Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Park
mesh_terms: D000075803:Angiopoietin-Like Protein 4; D042682:Angiopoietins / Q000096:biosynthesis*; D000818:Animals; D002460:Cell Line; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D053583:Interleukin-1beta / Q000378:metabolism*; D048670:MAP Kinase Kinase 4 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology
chemical_list: D000075803:Angiopoietin-Like Protein 4; D042682:Angiopoietins; C407088:Angptl4 protein, mouse; C587672:IL1B protein, mouse; D053583:Interleukin-1beta; D047428:Protein Kinase Inhibitors; D048670:MAP Kinase Kinase 4