Michihiko Usui

Learn More
Bone morphogenetic protein (BMP) controls osteoblast proliferation and differentiation through Smad proteins. Here we show that Tob, a member of the emerging family of antiproliferative proteins, is a negative regulator of BMP/Smad signaling in osteoblasts. Mice carrying a targeted deletion of the tob gene have a greater bone mass resulting from increased(More)
UNLABELLED Chondrocytes express RANKL, but their role in osteoclastogenesis is not clear. We report that hypertrophic chondrocytes induce osteoclast formation through RANKL production stimulated by BMP2 and Runx2/Smad1 and thus they may regulate resorption of calcified matrix by osteoclasts at growth plates. INTRODUCTION Bone morphogenetic protein (BMP)(More)
Recent studies have indicated that acetylcholine (ACh) plays a vital role in various tissues, while the role of ACh in bone metabolism remains unclear. Here we demonstrated that ACh induced cell proliferation and reduced alkaline phosphatase (ALP) activity via nicotinic (nAChRs) and muscarinic acetylcholine receptors (mAChRs) in osteoblasts. We detected(More)
Tob (transducer of erbB2) is a member of antiproliferative family proteins and acts as a bone morphogenic protein inhibitor as well as a suppressor of proliferation in T cells, which have been implicated in postmenopausal bone loss. To determine the effect of Tob deficiency on estrogen deficiency-induced bone loss, we analyzed bone metabolism after(More)
Tob is a recently reported novel bone morphogenetic protein (BMP) inhibitor, which originally was identified by West-Western procedure using ErbB2 as a probe and contains a nuclear localization signal. To further characterize the effects of Tob deficiency on BMP-induced new bone (NB) formation, we examined microcomputed tomography (microCT) on the(More)
Regulation of bone remodeling determines the levels of bone mass and its imbalance causes major skeletal diseases such as osteoporosis. A zinc finger protein, Schnurri-2 (SHN-2), was recently demonstrated to regulate bone morphogenetic protein-dependent adipogenesis and lymphogenesis. However, the role of SHN-2 in bone is not known. Here, we investigated(More)
UNLABELLED Cnot7 is a recently identified regulator of spermatogenesis in adult mice. Because Cnot7 binds to Tob, a BMP inhibitor shown to be involved in bone metabolism, we examined whether Cnot7 is involved in bone mass regulation by using adult Cnot7 deficient mice. Cnot7-/- mice exhibited a high bone mass phenotype. This was associated with an increase(More)
Periodontitis is characterized by chronic gingival tissue inflammation, and inflammatory mediators such as IL-8 and prostaglandin E(2) (PGE(2)) are associated with disease progression. Previously we showed that oxidatively modified low-density lipoprotein (oxLDL) was present in gingival crevicular fluid. In this study, the role of oxLDL in the gingival(More)
Mice lacking tob2, a member of the antiproliferative family genes, had decreased bone mass, and the number of osteoclasts differentiated from bone marrow cells was increased. Overexpression of Tob2 in stromal cells repressed vitamin D(3)-induced osteoclasts formation. Furthermore, expression of RANKL mRNA in stromal cells was increased in the absence of(More)
OBJECTIVE This study was designed to investigate the mechanism of salivary dysfunction in an experimental periodontitis rat model and to examine the improvements in salivary secretion following treatment of the experimental periodontitis. METHODS In the experimental periodontitis rat model, which included a unilateral ligature for 4 weeks around the(More)