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ABSTRACT: Mechanical stress is an important signal to determine the levels of bone mass. Unloading-induced osteoporosis is a critical issue in bed- ridden patients and astronauts. Many molecules have been suggested to be involved in sensing mechanical stress in bone, though the mechanisms involved in this phenomenon are not fully understood. Nck1is an adaptor protein known to mediate signaling from plasma membrane-activated receptors to cytosolic effectors regulating actin cytoskeleton remodeling. Nck1 has also been implicated in cellular responses to endoplasmic reticulum stress. In vitro, in case of cell stress the actin cytoskeleton is disrupted and in such cases Nck1 has been reported to enter the nucleus of the cells to mediate the nuclear actin polymerization. However, the role of Nck1 in vivo during the bone response to mechanical stimuli is unknown. The purpose of this study is to examine the role of Nck1 in unloading- induced bone loss in vivo. Sciatic and femoral nerve resection was conducted. Neurectomy- based unloading enhanced Nck1 gene expression in bone about two fold. Using the Nck1 deficient mice and control Nck1+/+, effects of neurectomy-based unloading on bone structure were examined. Unloading reduced bone volume in wild type mice by 30% whereas the levels in bone loss were exacerbated to 50% in Nck1 deficient mice due to neurectomy after four weeks. These data demonstrate that Nck1 gene deficiency accelerates the mechanical unloading-induced bone loss suggesting Nck1 to be a crucial molecule in mechanical stress mediated regulation in bone metabolism. J. Cell. Physiol. © 2012 Wiley Periodicals, Inc.
Journal of Cellular Physiology 12/2012; · 3.87 Impact Factor
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ABSTRACT: Substitution therapy of glucocorticoid is a major part of the treatment for 21-OHD (21-hydroxylase deficiency). However, the therapy causes two major adverse effects, impairment of linear growth and obesity, so that collecting precise growth data is essential for optimizing the therapy. We longitudinally evaluated the linear growth and the body composition of Japanese 21-OHD patients during childhood. For the present study, we chose 16 patients (eight of each sex) who were diagnosed during the newborn period, and continuously observed them in our institute until they were at least 15 years old. All patients were treated according to the guidelines from The Japanese Society for Pediatric Endocrinology. The final Ht-SDs of all the patients was -1.18 ± 0.85 SDS, and no significant differences were observed between males and females or between the simple virilising form and the salt wasting form. As previously reported, in spite of nearly normal height at the onset of puberty, the pubertal height gains were severely impaired, resulting in reduced final heights. Body composition of the patients was evaluated with BMI-SDs. Our longitudinal data showed that BMI was increased up to +1.23 SD in males and up to +1.75 SD in females, and that adiposity rebound was precipitated. Our study should alert physicians to the risk of metabolic syndrome and provide a framework for further studies of metabolic syndrome in 21-OHD patients.
Endocrine Journal 09/2012; · 2.03 Impact Factor
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ABSTRACT: An initial high-dose treatment of glucocorticoid has been proposed to prevent chronic androgen excess, improving the final height prognosis of 21-hydroxylase deficiency (21-OHD) patients. In Japan, it is recommended to use an extremely high-dose of hydrocortisone (HDC) (100-200 mg/m(2)/day) for initial treatment by the Japanese Society for Pediatric Endocrinology. However, a precise evaluation of the treatment has not been carried out. In this study, we retrospectively analysed the effects of initial high-dose HDC therapy on the linear growth of classical 21-OHD patients discovered by newborn screening. Thirty patients (14 females) were eligible for this study, all of whom were initiated with high dose HDC therapy. The height standard deviation score (Ht-SDS) was 0.76 ± 0.65 at birth, and decreased to -1SD or less until the age of 12 months, subsequently catching up by 3 years of age (-0.56 ± 0.76). The growth pattern and the height at the age of two years were very similar to those previously observed in patients without initial high dose HDC therapy. We did not find any significant difference in growth retrospectively between the high- or low-dose HDC group (initial treatments of ≥150 mg/m(2)/day and 100 mg/m(2)/day, respectively). Bone ages did not exceed chronological ages at the ages of three and six years. Our data suggest that an initial high-dose HDC treatment does not profoundly affect linear growth during first three years of life and that the treatment could be a valuable option for 21-OHD patients without having an obvious adverse effect on linear growth.
Endocrine Journal 07/2012; · 2.03 Impact Factor
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Pediatrics International 06/2010; 52(3):e154-7. · 0.63 Impact Factor
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ABSTRACT: Fracture healing is a process comprising of a local bleeding followed by inflammation and differentiation of mesenchymal cells that lead to formation of soft extracellular matrix tissue, cartilage and bone. This pathway includes endo-chondral bone formation and in part intra-membranous bone formation. During this process several sets of cytokines are involved in the regulation of the progress in fracture healing. This paper reviews the molecules involved in fracture healing.
Clinical calcium 06/2009; 19(5):634-40.
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Kentaro Miyai,
Mitsuhiro Yoneda,
Urara Hasegawa,
Sayaka Toita,
Yayoi Izu,
Hiroaki Hemmi,
Tadayoshi Hayata,
Yoichi Ezura,
Shuki Mizutani,
Kohei Miyazono,
Kazunari Akiyoshi,
Tadashi Yamamoto,
Masaki Noda
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ABSTRACT: Ectopic bone formation after joint replacement or brain injury in humans is a serious complication that causes immobility of joints and severe pain. However, mechanisms underlying such ectopic bone formation are not fully understood. Bone morphogenetic protein (BMPs) are defined as inducers of ectopic bone formation, and they are regulated by several types of inhibitors. ANA is an antiproliferative molecule that belongs to Tob/BTG family, but its activity in bone metabolism has not been known. Here, we examined the role of ANA on ectopic bone formation activity of BMP. In ANA-deficient and wild-type mice, BMP2 was implanted to induce ectopic bone formation in muscle. ANA deficiency increased mass of newly formed bone in vivo compared with wild-type based on 3D-muCT analyses. ANA mRNA was expressed in bone in vivo as well as in osteoblastic cells in vitro. Such ANA mRNA levels were increased by BMP2 treatment in MC3T3-E1 osteoblastic cells. Overexpression of ANA suppressed BMP-induced expression of luciferase reporter gene linked to BMP response elements in these cells. Conversely, ANA mRNA knockdown by small interference RNA enhanced the BMP-dependent BMP response element reporter expression. It also enhanced BMP-induced osteoblastic differentiation in muscle-derived C2C12 cells. Immunoprecipitation assay indicated that ANA interacts with Smad8. Thus, ANA is a suppressor of ectopic bone formation induced by BMP, and this inhibitory ANA activity is a part of the negative feedback regulation of BMP function.
Journal of Biological Chemistry 03/2009; 284(16):10593-600. · 4.77 Impact Factor
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ABSTRACT: We report a case of small cell carcinoma (SmCC) of the uterine cervix that metastasized to the bone marrow. A 60-year-old woman with stage IIB SmCC of the cervix was treated with three courses of neoadjuvant chemotherapy followed by radical hysterectomy. Because of the presence of a large residual tumor, the patient underwent postoperative adjuvant chemotherapy. Two months after the last course of chemotherapy, severe pancytopenia developed, and erythroblastic cells were found in the peripheral blood. The hematological disorder was shown to be secondary to bone marrow metastasis, and no other metastases were found. The patient died of the disease 8 months after the initial diagnosis. This case suggests that SmCC of the cervix can metastasize to bone marrow, that such metastasis can occur in isolation and lead to severe pancytopenia, influencing the clinical course of the disease.
Journal of Obstetrics and Gynaecology Research 08/2008; 34(4 Pt 2):692-5. · 0.94 Impact Factor
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ABSTRACT: A sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-ESI-MS-MS) method for the quantification of 17alpha-hydroxyprogesterone (17OHP) in human saliva has been developed and validated. The saliva was deproteinized with acetonitrile, purified using a Strata-X cartridge, derivatized with a highly proton-affinitive reagent, 2-hydrazinopyridine, and subjected to LC-MS-MS. Quantification was based on the selected reaction monitoring, and deuterated 17OHP was used as the internal standard. This method allowed the reproducible and accurate quantification of the salivary 17OHP using a 200-mul sample, and the limit of quantitation was 5.0 pg/ml. The developed method was applied to clinical studies. A linear relationship was found to be positive (r(2)=0.975) between the blood 17OHP level and the salivary 17OHP level measured using the proposed method. The result from the salivary 17OHP measurement in patients with congenital adrenal hyperplasia demonstrated that the proposed method is very useful for monitoring of the therapeutic efficacy during hormone replacement therapy.
Journal of Chromatography B 06/2008; 867(1):49-56. · 2.89 Impact Factor
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ABSTRACT: Transient growth hormone deficiency (GHD) is occasionally found in prepubertal individuals, and this phenomenon has been variously interpreted. Sex steroids enhance GH secretion; however, the cut-off values of provocative GH tests are not modified according to the physiological changes. Physiological changes in sex steroid levels are thought to cause the image of transient GHD. In addition, the reproducibility of provocative GH tests makes the interpretation complicated. We experienced a case of a boy with short stature who had undergone provocative GH tests at three different times: childhood (5 and 7 years old), before puberty (12 years old), and in adolescence (15 years old). Although the responses of GH in his childhood and adolescence were within the normal range, his prepubertal GH response was extremely low, as if he had "complete" GHD (peak GH: insulin test, 0.60 ng/ml; clonidine test, 0.78 ng/ml). No morphological changes were observed in the pituitary gland or hypothalamus on MRI. The level of insulin-like growth factor 1 was in the normal range for his age at this time. Here, we report the clinical course and endocrinological data of this case, and suggest that transient GHD is caused not only by the physiological effects of sex steroids but also by certain mechanisms that actively reduce GH secretion.
Endocrine Journal 02/2007; 54(6):1015-9. · 2.03 Impact Factor
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ABSTRACT: Uterine cervical adenocarcinoma (CAC) is a rare form of cervical cancer, constituting only 5-8% of all cervical epithelial malignancies. Loss of heterozygosity (LOH) analysis of CAC was undertaken to identify alterations of chromosomal loci that may play important roles in the development of this tumor type.
We analyzed loss of heterozygosity (LOH) using a total of 50 markers on 20 chromosomal arms in 37 cases of microdissected CAC DNA.
LOH of >40% was observed on 2p (50%), 3p (45%), 9p (45%), 11q (46%), 17p (57%), 17q (44%), 18q (57%), and 19p (44%). LOH of 30-40% was observed on 6p (38%), 6q (40%), and 10q (31%). Overall, mean LOH was 34% and fractional allelic loss (FAL) was 0.34. High-level and low-level microsatellite instability (MSI) was shown in four cases (11%) and six cases (16%), respectively. Frequency of LOH on10q was significantly higher in endometrioid-type than endocervical-type adenocarcinoma (71% versus 20%; P < 0.05). Conversely, 6q LOH was higher in endocervical type than endometrioid type (0% versus 60%; P < 0.05). 19p13.3 has been reported to be frequently deleted in adenoma malignum, a histological subtype of CAC. To define the critical regions of LOH in CAC in general, we further performed deletion mapping of 19p using 13 markers. Unlike adenoma malignum, multiple regions on 19p appeared to be important loci of LOH for CAC.
CACs develop with frequent LOH of multiple chromosomal arms, which may be related to its aggressive clinical behavior and poor prognosis. LOH of 10q may be unique to endometrioid-type CAC.
Gynecologic Oncology 08/2004; 94(1):115-20. · 3.89 Impact Factor
