Bone Abstracts

Tannerella forsythia is a gram-negative, anaerobic, asaccharolytic, fusiform bacterium. The presence of the bacterium is associated with various forms of periodontal disease, including gingivitis, chronic and aggressive periodontitis. The expression of GroEL, a bacterial heat shock protein, increases in stressful conditions such as infection. GroEL is a moonlighting protein that has multiple functions. The aim of this study was to evaluate the effect of T. forsyth...

Purpose: Osteoradionecrosis (ORN) of the mandible is a serious complication of radiation therapy, and accompanies soft tissue damage before bone loss appears. However, there is still no adequate treatment to heal the soft tissue damage of ORN. This study investigated the effect of platelet-derived growth factor (PDGF) or rat mesenchymal stem cells (rMSCs) on the healing of radiation-induced soft tissue injury by varying administration timing.Methods: Rat...

Objectives: Sex hormones and mechanical overload have been regarded as main causative factors in the pathogenesis of temporomandibular joint (TMJ) osteoarthritis. However, there was no report regarding the relevance of mechanical overload on the mandibular condyle with serum estrogen level. This study aimed to investigate changes of the mandibular condyle of TMJ in ovariectomized rat under increased loading, and to evaluate the inhibitory effect of systemic administration of 1...

Introduction: Low-magnitude, high-frequency (LMHF) mechanical stimuli lead to enhance bone formation and decrease resorption. This study aimed to investigate the effect of vibration on the bone loss induced by inflammatory cytokine, lipopolysaccharide (LPS).Methods and designs: Balb-C mice were administered to LPS (5 mg/kg) with two i.p. injections on days 0 and 4, while sham control group was injected with 400 μl of water for injection without LPS....

Objectives: To find the predicting factors for bone density in premenopausal women.Methods: Two hundred and forty-five premenopausal women without factors that can cause secondary osteoporosis were analyzed. Age, height, weight, change of height from peak height, history (Hx) of fracture, family Hx of hip or other fracture, Hx of estrogen use, calcium or vitamin D supplementation, smoking and previous Hx of amenorrhea more than 3 months were questioned. ...

Objectives: To evaluate the effect of hormone therapy on the change of bone mineral density in women who showed early menopause after pelvic radiation therapy for uterine cervical cancer.Materials and methods: Through retrospective chart review, the changes of bone mineral density in 63 women with early menopause after pelvic radiation therapy for uterine cervical cancer were evaluated. After the diagnosis of early menopause which was defined as level of...

The P2Y14 (purinergic receptor P2Y, G protein coupled, 14) receptor for UDP-glucose and other UDP-sugars has been implicated in the regulation of the stem cell compartment as well as neuroimmune function. However, the role of P2Y14 in osteoclast formation is completely unknown. We found that RANKL selectively induced P2Y14 among seven mammalian P2Y receptors when analysed at both the mRNA and protein level, but inhibitors of the MAP pathway suppressed induction of P2Y14 protei...

We sought to elucidate the effects of dietary caloric alterations on bone marrow adiposity and the effects of β-adrenergic signaling on marrow stromal cells’ adipogenic differentiation. Male 6-week-old C57BL/6 mice were assigned into three groups: an ad-libitum fed control diet (CON; 10 kcal% fat), a high calorie diet (HIGH; 60 kcal% fat) and a low calorie diet (LOW; 30% kcal restriction vs CON diet). In each diet group, mice were treated with vehicle (VEH: ...

Bisphosphonates (BPs) are widely used as antiresorptive drugs. However, one of most potent BPs, zoledronic acid (ZA) can cause BP-related osteonecrosis of the jaws (BRONJ) with a poorly understood pathophysiology. The aim of this study was to find a clue for the development of BRONJ by evaluating the cytotoxic effects of ZA on osteoblasts and examining the action mechanism of ZA on osteoclast differentiation. Jaw bone osteoblasts (JB-OBs), long bone osteoblasts (LB-OBs), and b...

Osteocytes may function as mechanotransducers by regulating local osteoclastogenesis. Reduced availability of oxygen, i.e. hypoxia could occur during disuse, bone development and fracture. Receptor activator of nuclear factor-κB ligand (RANKL) is an osteoblast/stromal cell derived essential factor for osteoclastogenesis. Hypoxia induced osteoclastogenesis via increased RANKL expression in osteoblasts was demonstrated. Hypoxic regulation of gene expression general...