Effect of nattokinase on the pathological conditions in streptozotocin induced diabetic rats.

Nattokinase (NK), also known as subtilisin NAT (EC 3.4.21.

Runx2 Regulates and Expressions and Galnt3 Decelerates Osteoid Mineralization by Stabilizing Fgf23.

Runx2 (runt related transcription factor 2) is an essential transcription factor for osteoblast proliferation and differentiation. Uridine diphosphate (UDP)-N-acetylgalactosamine (GalNAc): polypeptide GalNAc-transferase 3 (Galnt3) prevents proteolytic processing of fibroblast growth factor 23 (Fgf23), which is a hormone that regulates the serum level of phosphorus. and were expressed in osteoblasts and osteocytes, and expression was restricted to osteocytes in bone.

Deficiency in Osteoblasts Reduces the Trabecular Bone Due to Enhanced Osteoclastogenesis Likely through Osteoblast Apoptosis.

Bcl2l1 (Bcl-XL) belongs to the Bcl-2 family, Bcl2 and Bcl2-XL are major anti-apoptotic proteins, and the apoptosis of osteoblasts is a key event for bone homeostasis. As the functions of Bcl2l1 in osteoblasts and bone homeostasis remain unclear, we generated osteoblast-specific -deficient () mice using 2.3-kb Cre.

Sp7 Transgenic Mice with a Markedly Impaired Lacunocanalicular Network Induced Sost and Reduced Bone Mass by Unloading.

The relationship of lacunocanalicular network structure and mechanoresponse has not been well studied. The lacunocanalicular structures differed in the compression and tension sides, in the regions, and in genders in wild-type femoral cortical bone. The overexpression of Sp7 in osteoblasts resulted in thin and porous cortical bone with increased osteoclasts and apoptotic osteocytes, and the number of canaliculi was half of that in the wild-type mice, leading to a markedly impaired lacunocanalicular network.

Runt-related transcription factor-2 (Runx2) is required for bone matrix protein gene expression in committed osteoblasts in mice.

Runt-related transcription factor-2 (Runx2) is an essential transcription factor for osteoblast differentiation. However, its functions after the commitment into osteoblasts are controversial and remain to be clarified. We generated enhanced green fluorescent protein (EGFP)-Cre transgenic mice driven by the 2.

Overexpression of BCLXL in Osteoblasts Inhibits Osteoblast Apoptosis and Increases Bone Volume and Strength.

The Bcl2 family proteins, Bcl2 and BclXL, suppress apoptosis by preventing the release of caspase activators from mitochondria through the inhibition of Bax subfamily proteins. We reported that BCL2 overexpression in osteoblasts using the 2.3 kb Col1a1 promoter increased osteoblast proliferation, failed to reduce osteoblast apoptosis, inhibited osteoblast maturation, and reduced the number of osteocyte processes, leading to massive osteocyte death.

Osteocyte network; a negative regulatory system for bone mass augmented by the induction of Rankl in osteoblasts and Sost in osteocytes at unloading.

Reduced mechanical stress is a major cause of osteoporosis in the elderly, and the osteocyte network, which comprises a communication system through processes and canaliculi throughout bone, is thought to be a mechanosensor and mechanotransduction system; however, the functions of osteocytes are still controversial and remain to be clarified. Unexpectedly, we found that overexpression of BCL2 in osteoblasts eventually caused osteocyte apoptosis. Osteoblast and osteoclast differentiation were unaffected by BCL2 transgene in vitro.

SP7 inhibits osteoblast differentiation at a late stage in mice.

RUNX2 and SP7 are essential transcription factors for osteoblast differentiation at an early stage. Although RUNX2 inhibits osteoblast differentiation at a late stage, the function of SP7 at the late stage of osteoblast differentiation is not fully elucidated. Thus, we pursued the function of SP7 in osteoblast differentiation.

Overexpression of Bcl2 in osteoblasts inhibits osteoblast differentiation and induces osteocyte apoptosis.

Bcl2 subfamily proteins, including Bcl2 and Bcl-X(L), inhibit apoptosis. As osteoblast apoptosis is in part responsible for osteoporosis in sex steroid deficiency, glucocorticoid excess, and aging, bone loss might be inhibited by the upregulation of Bcl2; however, the effects of Bcl2 overexpression on osteoblast differentiation and bone development and maintenance have not been fully investigated. To investigate these issues, we established two lines of osteoblast-specific BCL2 transgenic mice.

Antihypertensive effects of continuous oral administration of nattokinase and its fragments in spontaneously hypertensive rats.

To determine whether the antihypertensive effect of nattokinase is associated with the protease activity of this enzyme, we compared nattokinase with the fragments derived from nattokinase, which possessed no protease activity, in terms of the effect on hypertension in spontaneously hypertensive rats (SHR). In the continuous oral administration test, the groups were given a basic diet alone (control), the basic diet containing nattokinase (0.2, 2.

Pyruvate dehydrogenase kinase 4 induces bone loss at unloading by promoting osteoclastogenesis.

Disuse osteoporosis, which occurs commonly in prolonged bed rest and immobilization, is becoming a major problem in modern societies; however, the molecular mechanisms underlying unloading-driven bone loss have not been fully elucidated. The osteocyte network is considered to be an ideal mechanosensor and mechanotransduction system. We searched for the molecules responsible for disuse osteoporosis using BCL2 transgenic mice, in which the osteocyte network was disrupted.

Anti-osteoporosis effect of 5-bromo-2-(4-chlorobenzoyl)-(Z)-3-(2-cyano-3-hydroxybut-2-enonyl)aminobenzo[b]furan: a novel selective estrogen receptor modulator.

The benzo[b]furan derivative MU314 inhibits in vitro bone resorption as potently as β-estradiol (E(2)). Here, we examined the point of action on the anti-osteoporotic effects of MU314. MU314 (10 nM) suppressed lacunae formation by osteoclastic cells and ICI-182,780, a pure E(2) antagonist, inhibited this effect.

Preparation of novel (Z)-4-ylidenebenzo[b]furo[3,2-d][1,3]oxazines and their biological activity.

A reaction of 2-acetyl-3-acylaminobenzo[b]furans (9d-o) with Vilsmeier (VM) reagent afforded a mixture of (E)- and (Z)-{(E)-2-aralkenylbenzo[b]furo[3,2-d][1,3]oxazin-4-ylidene}acetaldehydes (5) with a characteristic exo-formylmethylene group on the oxazine ring. The Z-isomer was more stable than the E-isomer. The Z-isomers ((Z)-5) were reacted with phosphonate reagents under two different conditions to obtain various butadiene derivatives (12) containing benzo[b]furo[3,2-d][1,3]oxazine skeleton.

Runx2 determines bone maturity and turnover rate in postnatal bone development and is involved in bone loss in estrogen deficiency.

Runx2 is an essential transcription factor for osteoblast differentiation. However, the functions of Runx2 in postnatal bone development remain to be clarified. Introduction of dominant-negative (dn)-Runx2 did not inhibit Col1a1 and osteocalcin expression in mature osteoblastic cells.

A novel oxazine ring closure reaction affording (Z)-((E)-2-styrylbenzo[b]furo[3,2-d][1,3]oxazin-4-ylideno)acetaldehydes and their anti-osteoclastic bone resorption activity.

A novel oxazine ring formation method was established using the reaction of 2-acetyl-(E)-3-styrylcarbonylaminobenzo[b]furans (4) with Vilsmeier-Haack-Arnold reagent to afford (E and Z)-((E)-2-styrylbenzo[b]furo[3,2-d][1,3]oxazin-4-ylideno)acetaldehydes (5). (Z)-4-(8-Bromo-(E)-2-styrylbenzo[b]furo[3,2-d][1,3]oxazin-4-ylideno)but-(E)-2-enoic acid ethyl ester (6b), derived from (Z)-5a, showed significantly potent anti-osteoclastic bone resorption activity comparable to 17beta-estradiol (E2).

Cbf beta regulates Runx2 function isoform-dependently in postnatal bone development.

Runx2 and Cbfbeta are essential for skeletal development during the embryonic stage. Runx2 has two isoforms with different N-termini. We examined the functions of the Runx2 isoforms and Cbfbeta in postnatal bone development.

Dexamethasone inhibits insulin-induced chondrogenesis of ATDC5 cells by preventing PI3K-Akt signaling and DNA binding of Runx2.

Glucocorticoids play important roles in cell growth and differentiation. In this study, we investigated the effect of application of dexamethasone (DEX) at the early stage of chondrogenesis using the prechondrogenic cell line, ATDC5, which differentiates into chondrocytes in the presence of insulin. When ATDC5 cells were cultured in the presence of DEX and insulin, DEX inhibited insulin-induced cellular condensation and subsequent cartilaginous nodule formation, and reduced proteoglycan synthesis and type II collagen expression dose-dependently.

Osteoporosis requires bone-specific statins.

Remedies for primary osteoporosis are increasing in brands but not always with concomitant improvements in efficacy and safety. Clinical studies suggest that nitrogen-containing bisphosphonates alone display sufficient practical effectiveness to survive as effective therapy. However, their less effectiveness in highly osteopenic patients due to their lack of genuine bone anabolic effect waits improvements.

Runx2 induces osteoblast and chondrocyte differentiation and enhances their migration by coupling with PI3K-Akt signaling.

Runx2 and phosphatidylinositol 3-kinase (PI3K)-Akt signaling play important roles in osteoblast and chondrocyte differentiation. We investigated the relationship between Runx2 and PI3K-Akt signaling. Forced expression of Runx2 enhanced osteoblastic differentiation of C3H10T1/2 and MC3T3-E1 cells and enhanced chondrogenic differentiation of ATDC5 cells, whereas these effects were blocked by treatment with IGF-I antibody or LY294002 or adenoviral introduction of dominant-negative (dn)-Akt.

Statins inhibit osteoblast migration by inhibiting Rac-Akt signaling.

Cell migration is a key event in repair and remodeling of skeletal tissues, but the mechanism of osteoblast migration has not been resolved. Statins, which are inhibitors of 3-hydroxy-3-methylglutaryl CoA reductase, increase bone. However, the effect of statins on osteoblast migration remains to be clarified.

Induction of osteoclast differentiation by Runx2 through receptor activator of nuclear factor-kappa B ligand (RANKL) and osteoprotegerin regulation and partial rescue of osteoclastogenesis in Runx2-/- mice by RANKL transgene.

Receptor activator of nuclear factor-kappaB ligand (RANKL), osteoprotegerin (OPG), and macrophage-colony stimulating factor play essential roles in the regulation of osteoclastogenesis. Runx2-deficient (Runx2-/-) mice showed a complete lack of bone formation because of maturational arrest of osteoblasts and disturbed chondrocyte maturation. Further, osteoclasts were absent in these mice, in which OPG and macrophage-colony stimulating factor were normally expressed, but RANKL expression was severely diminished.

Core-binding factor beta interacts with Runx2 and is required for skeletal development.

Core-binding factor beta (CBFbeta, also called polyomavirus enhancer binding protein 2beta (PEBP2B)) is associated with an inversion of chromosome 16 and is associated with acute myeloid leukemia in humans. CBFbeta forms a heterodimer with RUNX1 (runt-related transcription factor 1), which has a DNA binding domain homologous to the pair-rule protein runt in Drosophila melanogaster. Both RUNX1 and CBFbeta are essential for hematopoiesis.

New signaling pathway for parathyroid hormone and cyclic AMP action on extracellular-regulated kinase and cell proliferation in bone cells. Checkpoint of modulation by cyclic AMP.

cAMP signaling, activated by extracellular stimuli such as parathyroid hormone, has cell type-specific effects important for cellular proliferation and differentiation in bone cells. Recent evidence of a second enzyme target for cAMP suggests divergent effects on extracellular-regulated kinase (ERK) activity depending on Epac/Rap1/B-Raf signaling. We investigated the molecular mechanism of the dual functionality of cAMP on cell proliferation in clonal bone cell types.