title: Thymoquinone prevents RANKL-induced osteoclastogenesis activation and osteolysis in an in vivo model of inflammation by suppressing NF-KB and MAPK Signalling.
abstract: Osteoclasts are multinuclear giant cells responsible for bone resorption in inflammatory bone diseases such as osteoporosis, rheumatoid arthritis and periodontitis. Because of deleterious side effects with currently available drugs the search continues for novel effective and safe therapies. Thymoquinone (TQ), the major bioactive component of Nigella sativa has been investigated for its anti-inflammatory, antioxidant and anticancer activities. However, its effects in osteoclastogenesis have not been reported. In the present study we show for the first time that TQ inhibits nuclear factor-KB ligand (RANKL) induced osteoclastogenesis in RAW 264.7 and primary bone marrow derived macrophages (BMMs) cells. RANKL induced osteoclastogenesis is associated with increased expression of multiple transcription factors via activation of NF-KB, MAPKs signalling and reactive oxygen species (ROS). Mechanistically TQ blocked the RANKL induced NF-KB activation by attenuating the phosphorylation of IkB kinase (IKKα/β). Interestingly, in RAW 264.7 cells TQ inhibited the RANKL induced phosphorylation of MAPKs and mRNA expression of osteoclastic specific genes such as TRAP, DC-STAMP, NFATc1 and c-Fos. In addition, TQ also decreased the RANKL stimulated ROS generation in macropahges (RAW 264.7) and H2O2 induced ROS generation in osteoblasts (MC-3T3-E1). Consistent with in vitro results, TQ inhibited lipopolysaccharide (LPS) induced bone resorption by suppressing the osteoclastogenesis. Indeed, micro-CT analysis showed that bone mineral density (BMD) and bone architecture parameters were positively modulated by TQ. Taken together our data demonstrate that TQ has antiosteoclastogenic effect by inhibiting inflammation induced activation of MAPKs, NF-KB and ROS generation followed by suppressing the gene expression of c-Fos and NFATc1 in osteoclast precursors.
authors.affiliation: Department of Pharmacology & Toxicology, National Institute of Pharmaceutical Education & Research, Balanagar, Hyderabad, Telengana 500 037, India.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Thummuri
authors.affiliation: Department of Pharmacology & Toxicology, National Institute of Pharmaceutical Education & Research, Balanagar, Hyderabad, Telengana 500 037, India.
authors.forename: Manish Kumar
authors.initials: MK
authors.lastname: Jeengar
authors.affiliation: Department of Pharmacology & Toxicology, National Institute of Pharmaceutical Education & Research, Balanagar, Hyderabad, Telengana 500 037, India.
authors.forename: Shweta
authors.initials: S
authors.lastname: Shrivastava
authors.affiliation: National Centre for Laboratory Animal Sciences, National Institute of Nutrition, Habsiguda, Hyderabad, Telengana 500 037, India.
authors.forename: Harishankar
authors.initials: H
authors.lastname: Nemani
authors.affiliation: National Centre for Laboratory Animal Sciences, National Institute of Nutrition, Habsiguda, Hyderabad, Telengana 500 037, India.
authors.forename: Ravindar Naik
authors.initials: RN
authors.lastname: Ramavat
authors.affiliation: Comparative Oncology Program & Small Animal Imaging Facility, Advanced Center for Treatment, Research & Education in Cancer (ACTREC), Tata Memorial Centre, Kharghar, Navi Mumbai 410 210, India.
authors.forename: Pradip
authors.initials: P
authors.lastname: Chaudhari
authors.affiliation: Department of Pharmacology & Toxicology, National Institute of Pharmaceutical Education & Research, Balanagar, Hyderabad, Telengana 500 037, India. Electronic address: vgmnaidu@niperhyd.ac.in.
authors.forename: V G M
authors.initials: VG
authors.lastname: Naidu
mesh_terms: D016475:3T3 Cells; D000818:Animals; D016227:Benzoquinones / Q000494:pharmacology*; D007249:Inflammation / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008070:Lipopolysaccharides / Q000633:toxicity; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D010010:Osteoclasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D010014:Osteolysis / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D018384:Oxidative Stress / Q000187:drug effects; D010766:Phosphorylation; D053245:RANK Ligand / Q000378:metabolism*; D000067996:RAW 264.7 Cells
chemical_list: D016227:Benzoquinones; D008070:Lipopolysaccharides; D016328:NF-kappa B; D053245:RANK Ligand; C505689:Tnfsf11 protein, mouse; C003466:thymoquinone
keywords: DC-FDA (PubChem CID: 104913); Dimethyl sulfoxide (PubChem CID: 2733526); Hydrogen peroxide (PubChem CID: 784); Ketamine (PubChem CID: 3821); Lipopolysaccharide (PubChem CID: 11970143); NF-KB; Osteoclastogenesis; Osteolysis; RANKL; Tamoxifen (PubChem CID: 2733526); Thiazolyl blue tetrazolium bromide (PubChem CID: 64965); Thymoquinone; Thymoquinone (PubChem CID: 10281); Xylazine (PubChem CID: 5707)