title: Decreased jaw bone density and osteoblastic insulin signaling in a model of obesity.
abstract: Previous studies have demonstrated that decreased bone mass results from either the impairment of osteoblastic insulin signaling or obesity. Our previous study revealed that 12-week high-fat-diet (HFD) consumption caused obesity as well as peripheral and brain insulin resistance. However, the osteoblastic insulin resistance induced by HFD has not been elucidated. Therefore, we hypothesized that 12-week HFD rats exhibited not only peripheral insulin resistance but also osteoblastic insulin resistance, which leads to decreased jawbone quality. We found that the jawbones of rats fed a 12-week HFD exhibited increased osteoporosis. The osteoblastic cells isolated from HFD-fed rats exhibited the impairment of osteoblastic insulin signaling as well as reduction of cell proliferation and survival. In conclusion, this study demonstrated that insulin resistance induced by 12-week HFD impaired osteoblastic insulin signaling, osteoblast proliferation, and osteoblast survival and resulted in osteoporosis in the jawbone.
authors.affiliation: Department of Oral Biology and Diagnostic Science, Faculty of Dentistry.
authors.forename: S N
authors.initials: SN
authors.lastname: Pramojanee
authors.forename: M
authors.initials: M
authors.lastname: Phimphilai
authors.forename: S
authors.initials: S
authors.lastname: Kumphune
authors.forename: N
authors.initials: N
authors.lastname: Chattipakorn
authors.forename: S C
authors.initials: SC
authors.lastname: Chattipakorn
mesh_terms: D000539:Alveolar Process / Q000473:pathology; D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001786:Blood Glucose / Q000032:analysis; D015519:Bone Density / Q000502:physiology*; D049109:Cell Proliferation; D002470:Cell Survival / Q000502:physiology; D002784:Cholesterol / Q000097:blood; D059305:Diet, High-Fat / Q000009:adverse effects; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D008334:Mandible / Q000473:pathology*; D009765:Obesity / Q000209:etiology / Q000503:physiopathology*; D051058:Oncogene Protein v-akt / Q000032:analysis; D010006:Osteoblasts / Q000378:metabolism / Q000502:physiology*; D015675:Osteocalcin / Q000097:blood; D010012:Osteogenesis / Q000502:physiology; D010024:Osteoporosis / Q000209:etiology / Q000473:pathology; D010766:Phosphorylation; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D011972:Receptor, Insulin / Q000032:analysis; D015398:Signal Transduction / Q000502:physiology; D055114:X-Ray Microtomography
chemical_list: D001786:Blood Glucose; D007328:Insulin; D015675:Osteocalcin; D002784:Cholesterol; D011972:Receptor, Insulin; D051058:Oncogene Protein v-akt
keywords: cell apoptosis; cell proliferation; insulin resistance; mandible; obese; osteoblast