PMID- 29859535 OWN - NLM STAT- MEDLINE DCOM- 20181017 LR - 20181114 IS - 1476-511X (Electronic) IS - 1476-511X (Linking) VI - 17 IP - 1 DP - 2018 Jun 2 TI - Toll-like receptor 2 activation primes and upregulates osteoclastogenesis via lox-1. PG - 132 LID - 10.1186/s12944-018-0787-4 [doi] LID - 132 AB - BACKGROUND: Lectin-like oxidized low-density-lipoprotein receptor 1 (Lox-1) is the receptor for oxidized low-density lipoprotein (oxLDL), a mediator in dyslipidemia. Toll-like receptor (TLR)-2 and - 4 are receptors of lipopolysaccharide (LPS) from Porphyromonas gingivalis, a major pathogen of chronic periodontitis. Although some reports have demonstrated that periodontitis has an adverse effect on dyslipidemia, little is clear that the mechanism is explained the effects of dyslipidemia on osteoclastogenesis. We have hypothesized that osteoclast oxLDL has directly effect on osteoclasts (OCs), and therefore alveolar bone loss on periodontitis may be increased by dyslipidemia. The present study aimed to elucidate the effect of Lox-1 on osteoclastogenesis associated with TLRs in vitro. METHODS: Mouse bone marrow cells (BMCs) were stimulated with macrophage colony-stimulating factor into bone marrow macrophages (BMMs). The cells were also stimulated with synthetic ligands for TLR2 (Pam3CSK4) or TLR4 (Lipid A), with or without receptor activator of nuclear factor kappa-B ligand (RANKL), and assessed for osteoclastogenesis by tartrate-resistant acid phosphatase (TRAP) staining, immunostaining, western blotting, flow activated cell sorting (FACS) analysis, real-time polymerase chain reaction (PCR), and reverse transcription PCR. RESULTS: Lox-1 expression was significantly upregulated by Pam3CSK4 and Lipid A in BMCs (p < 0.05), but not in BMMs. FACS analysis identified that Pam3CSK4 upregulated RANK and Lox-1 expression in BMCs. TRAP-positive cells were not increased by stimulation with Pam3CSK4 alone, but were increased by stimulation with combination combined Pam3CSK and oxLDL. Expression of both Lox-1 and myeloid differentiation factor 88 (MyD88), an essential adaptor protein in the TLR signaling pathway, were suppressed by inhibitors of TLR2, TLR4 and mitogen-activated protein kinase (MAPK). CONCLUSIONS: This study supports that osteoclastogenesis is promoted under the coexistence of oxLDL by TLR2-induced upregulation of Lox-1 in BMCs. This indicates that periodontitis could worsen with progression of dyslipidemia. FAU - Ohgi, Kimiko AU - Ohgi K AD - Department of Odontology, Fukuoka Dental College, Fukuoka, 8140193, Japan. FAU - Kajiya, Hiroshi AU - Kajiya H AUID- ORCID: 0000-0003-3275-3632 AD - Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka, 8140193, Japan. kajiya@college.fdcnet.ac.jp. FAU - Goto-T, Kazuko AU - Goto-T K AD - Department of Dental Hygiene, Fukuoka College of Health Sciences, Fukuoka, 8140193, Japan. FAU - Okamoto, Fujio AU - Okamoto F AD - Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka, 8140193, Japan. FAU - Yoshinaga, Yasunori AU - Yoshinaga Y AD - Department of Odontology, Fukuoka Dental College, Fukuoka, 8140193, Japan. FAU - Okabe, Koji AU - Okabe K AD - Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka, 8140193, Japan. FAU - Sakagami, Ryuji AU - Sakagami R AD - Department of Odontology, Fukuoka Dental College, Fukuoka, 8140193, Japan. LA - eng GR - 15K11405/Ministry of Education, Culture, Sports, Science and Technology/ PT - Journal Article DEP - 20180602 PL - England TA - Lipids Health Dis JT - Lipids in health and disease JID - 101147696 RN - 0 (Lipoproteins, LDL) RN - 0 (Scavenger Receptors, Class E) RN - 0 (Tlr2 protein, mouse) RN - 0 (Toll-Like Receptor 2) RN - 0 (oxidized low density lipoprotein) SB - IM MH - Animals MH - Bone Marrow Cells/*metabolism/physiology MH - Cell Differentiation MH - Lipoproteins, LDL MH - Macrophages MH - Male MH - Mice MH - *Osteogenesis MH - Periodontitis MH - Scavenger Receptors, Class E/metabolism/*physiology MH - *Signal Transduction MH - Toll-Like Receptor 2/*metabolism PMC - PMC5985062 OTO - NOTNLM OT - Dyslipidemia OT - Lectin-like oxidized low-density-lipoprotein receptor 1 OT - Osteoclastogenesis OT - Toll-like receptor COIS- ETHICS APPROVAL AND CONSENT TO PARTICIPATE: Not applicable. COMPETING INTERESTS: The authors declare that they have no competing interests. PUBLISHER'S NOTE: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. EDAT- 2018/06/04 06:00 MHDA- 2018/10/18 06:00 PMCR- 2018/06/02 CRDT- 2018/06/04 06:00 PHST- 2018/01/28 00:00 [received] PHST- 2018/05/23 00:00 [accepted] PHST- 2018/06/04 06:00 [entrez] PHST- 2018/06/04 06:00 [pubmed] PHST- 2018/10/18 06:00 [medline] PHST- 2018/06/02 00:00 [pmc-release] AID - 10.1186/s12944-018-0787-4 [pii] AID - 787 [pii] AID - 10.1186/s12944-018-0787-4 [doi] PST - epublish SO - Lipids Health Dis. 2018 Jun 2;17(1):132. doi: 10.1186/s12944-018-0787-4.