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Chansoria H, Chandrakar R, Chetana HK, Kamadal N, Pamecha S, Kaur H, Tiwari R. Age and Gender Estimation Using the Osseous Microanatomy: Original Research. JOURNAL OF PHARMACY AND BIOALLIED SCIENCES 2024; 16:S233-S235. [PMID: 38595368 PMCID: PMC11000899 DOI: 10.4103/jpbs.jpbs_474_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/03/2023] [Accepted: 10/01/2023] [Indexed: 04/11/2024] Open
Abstract
Aim This study was performed with the idea of assessing age and gender utilizing differences in osseous microanatomy in human jawbones. Materials and Methods The study was conducted retrospectively among human jawbone samples. Various morphometric assessments such as trabecular width, marrow space, and their corelation were studied. In the samples, variations among osteon numbers, differences in the shapes of the osteocytes of jawbones, and amount of inflammation in the bony areas were recorded. Results It was noted in this study that mean values of the diameter of the Haversian canal and vessel density had a noteworthy increase in female jawbone samples. The amount of osteocytes in both female and male bone samples was also statistically significant in terms of the correlation coefficient. Conclusion We concluded that more sensitive identification of human remains, that is, age and gender analysis, can be performed by histomorphometric evaluation of bone remains.
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Affiliation(s)
- Harsh Chansoria
- Department of Prosthodontics Crown and Bridge, Government College of Dentistry Indore, MP, India
| | - Rolly Chandrakar
- Department of Anatomy, Chandulal Chandrakar Memorial Government Medical College, Chhattisgarh, India
| | - HK Chetana
- Department of Oral Medicine and Radiology, GDC and RI, Ballari, Karnataka, India
| | - Neelamma Kamadal
- Department of Oral and Maxillofacial Surgery, Al ameen Dental College Vijayapura, Karnataka, India
| | - Sonal Pamecha
- Department of Prosthodontics, Pacific Dental College and Hospital Udaipur, Rajasthan, India
| | - Harveen Kaur
- Department of Oral Medicine and Radiology, Dr Harvansh Singh Judge Institute of Dental Sciences and Hospital, Panjab University, Chandigarh, India
| | - Rahul Tiwari
- Consultant Oral and Maxillofacial Surgeon, CLOVE Dental, Visakhapatnam, Andhra Pradesh, India
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Abstract
Cell migration is highly sensitive to fluid shear stress (FSS) in blood flow or interstitial fluid flow. However, whether the FSS gradient can regulate the migration of cells remains unclear. In this work, we constructed a parallel-plate flow chamber with different FSS gradients and verified the gradient flow field by particle image velocimetry measurements and finite element analyses. We then investigated the effect of FSS magnitudes and gradients on the migration of osteoclast precursor RAW264.7 cells. Results showed that the cells sensed the FSS gradient and migrated toward the low-FSS region. This FSS gradient-induced migration tended to occur in low-FSS magnitudes and high gradients, e.g., the migration angle relative to flow direction was approximately 90° for 0.1 Pa FSS and 0.2 Pa mm−1 FSS gradient. When chemically inhibiting the calcium signaling pathways of the mechanosensitive cation channel, endoplasmic reticulum, phospholipase C, and extracellular calcium, the cell migration toward the low-FSS region was significantly reduced. This study may provide insights into the mechanism of the recruitment of osteoclast precursors at the site of bone resorption and of mechanical stimulation-induced bone remodeling.
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Affiliation(s)
- Yan Gao
- a Biomechanics Lab, Department of Mechanics, School of Aerospace Engineering , Beijing Institute of Technology , Beijing , P. R. China
| | - Taiyang Li
- a Biomechanics Lab, Department of Mechanics, School of Aerospace Engineering , Beijing Institute of Technology , Beijing , P. R. China
| | - Qing Sun
- a Biomechanics Lab, Department of Mechanics, School of Aerospace Engineering , Beijing Institute of Technology , Beijing , P. R. China
| | - Bo Huo
- a Biomechanics Lab, Department of Mechanics, School of Aerospace Engineering , Beijing Institute of Technology , Beijing , P. R. China
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Tan LH, Sykes PH, Alkaisi MM, Evans JJ. The characteristics of Ishikawa endometrial cancer cells are modified by substrate topography with cell-like features and the polymer surface. Int J Nanomedicine 2015; 10:4883-95. [PMID: 26346435 PMCID: PMC4531047 DOI: 10.2147/ijn.s86336] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Conventional in vitro culture studies on flat surfaces do not reproduce tissue environments, which have inherent topographical mechanical signals. To understand the impact of these mechanical signals better, we use a cell imprinting technique to replicate cell features onto hard polymer culture surfaces as an alternative platform for investigating biomechanical effects on cells; the high-resolution replication of cells offers the micro- and nanotopography experienced in typical cell–cell interactions. We call this platform a Bioimprint. Cells of an endometrial adenocarcinoma cell line, Ishikawa, were cultured on a bioimprinted substrate, in which Ishikawa cells were replicated on polymethacrylate (pMA) and polystyrene (pST), and compared to cells cultured on flat surfaces. Characteristics of cells, incorporating morphology and cell responses, including expression of adhesion-associated molecules and cell proliferation, were studied. In this project, we fabricated two different topographies for the cells to grow on: a negative imprint that creates cell-shaped hollows and a positive imprint that recreates the raised surface topography of a cell layer. We used two different substrate materials, pMA and pST. We observed that cells on imprinted substrates of both polymers, compared to cells on flat surfaces, exhibited higher expression of β1-integrin, focal adhesion kinase, and cytokeratin-18. Compared to cells on flat surfaces, cells were larger on imprinted pMA and more in number, whereas on pST-imprinted surfaces, cells were smaller and fewer than those on a flat pST surface. This method, which provided substrates in vitro with cell-like features, enabled the study of effects of topographies that are similar to those experienced by cells in vivo. The observations establish that such a physical environment has an effect on cancer cell behavior independent of the characteristics of the substrate. The results support the concept that the physical topography of a cell’s environment may modulate crucial oncological signaling pathways; this suggests the possibility of cancer therapies that target pathways associated with the response to mechanical stimuli.
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Affiliation(s)
- Li Hui Tan
- Department of Obstetrics and Gynaecology, University of Otago, Christchurch, New Zealand ; MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand
| | - Peter H Sykes
- Department of Obstetrics and Gynaecology, University of Otago, Christchurch, New Zealand
| | - Maan M Alkaisi
- MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand ; Department of Electrical and Computer Engineering, University of Canterbury, Christchurch, New Zealand
| | - John J Evans
- Department of Obstetrics and Gynaecology, University of Otago, Christchurch, New Zealand ; MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand ; Centre for Neuroendocrinology, University of Otago, Christchurch, New Zealand
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Joiner DM, Tayim RJ, McElderry JD, Morris MD, Goldstein SA. Aged male rats regenerate cortical bone with reduced osteocyte density and reduced secretion of nitric oxide after mechanical stimulation. Calcif Tissue Int 2014; 94:484-94. [PMID: 24370615 PMCID: PMC4791168 DOI: 10.1007/s00223-013-9832-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Accepted: 12/01/2013] [Indexed: 01/05/2023]
Abstract
Mechanical loading is integral to the repair of bone damage. Osteocytes are mechanosensors in bone and participate in signaling through gap junction channels, which are primarily comprised of connexin 43 (Cx43). Nitric oxide (NO) and prostaglandin E2 (PGE2) have anabolic and catabolic effects on bone, and the secretion of these molecules occurs after mechanical stimulation. The effect of age on the repair of bone tissue after damage and on the ability of regenerated bone to transduce mechanical stimulation into a cellular response is unexplored. The goal of this study was to examine (1) osteocytes and their mineralized matrix within regenerated bone from aged and mature animals and (2) the ability of regenerated bone explants from aged and mature animals to transduce cyclic mechanical loading into a cellular response through NO and PGE2 secretion. Bilateral cortical defects were created in the diaphysis of aged (21-month-old) or mature (6-month-old) male rats, and new bone tissue was allowed to grow into a custom implant of controlled geometry. Mineralization and mineral-to-matrix ratio were significantly higher in regenerated bone from aged animals, while lacunar and osteocyte density and phosphorylated (pCx43) and total Cx43 protein were significantly lower, relative to mature animals. Regenerated bone from mature rats had increased pCx43 protein and PGE2 secretion with loading and greater NO secretion relative to aged animals. Reduced osteocyte density and Cx43 in regenerated bone in aged animals could limit the establishment of gap junctions as well as NO and PGE2 secretion after loading, thereby altering bone formation and resorption in vivo.
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Affiliation(s)
- Danese M Joiner
- Orthopaedic Research Laboratories, University of Michigan, Biomedical Science Research Building, 109 Zina Pitcher Place Bay 4888, Ann Arbor, MI, 48108, USA,
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Bonnet N, Gineyts E, Ammann P, Conway SJ, Garnero P, Ferrari S. Periostin deficiency increases bone damage and impairs injury response to fatigue loading in adult mice. PLoS One 2013; 8:e78347. [PMID: 24167618 PMCID: PMC3805534 DOI: 10.1371/journal.pone.0078347] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 09/16/2013] [Indexed: 01/09/2023] Open
Abstract
Bone damage removal and callus formation in response to fatigue loading are essential to prevent fractures. Periostin (Postn) is a matricellular protein that mediates adaptive response of cortical bone to loading. Whether and how periostin influences damage and the injury response to fatigue remains unknown. We investigated the skeletal response of Postn(-/-) and Postn(+/+) mice after fatigue stimulus by axial compression of their tibia. In Postn(+/+) mice, cracks number and surface (CsNb, CsS) increased 1h after fatigue, with a decrease in strength compared to non-fatigued tibia. At 15 days, CsNb had started to decline, while CtTV and CtBV increased in fatigued vs non-fatigued tibia, reflecting a woven bone response that was present in 75% of the fatigued bones. Cortical porosity and remodelling also prominently increased in the fatigued tibia of Postn(+/+) mice. At 30 days, paralleling a continuous removal of cortical damage, strength of the fatigued tibia was similar to the non-fatigue tibia. In Postn(-/-) mice, cracks were detectable even in the absence of fatigue, while the amount of collagen crosslinks and tissue hardness was decreased compared to Postn(+/+). Fatigue significantly increased CsNb and CsS in Postn(-/-), but was not associated with changes in CtTV and CtBV, as only 16% of the fatigued bones formed some woven bone. Cortical porosity and remodelling did not increase either after fatigue in Postn(-/-), and the level of damage remained high even after 30 days. As a result, strength remained compromised in Postn(-/-) mice. Contrary to Postn(+/+), which osteocytic lacunae showed a change in the degree of anisotropy (DA) after fatigue, Postn(-/-) showed no DA change. Hence periostin appears to influence bone materials properties, damage accumulation and repair, including local modeling/remodeling processes in response to fatigue. These observations suggest that the level of periostin expression could influence the propensity to fatigue fractures.
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Affiliation(s)
- Nicolas Bonnet
- Division of Bone Diseases, Department of Internal Medicine Specialties, Geneva University Hospital, Geneva, Switzerland
- * E-mail :
| | - Evelyne Gineyts
- INSERM UMR 1033, University of Lyon, Hôpital Edouard Herriot, Lyon, France
| | - Patrick Ammann
- Division of Bone Diseases, Department of Internal Medicine Specialties, Geneva University Hospital, Geneva, Switzerland
| | - Simon J. Conway
- Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Patrick Garnero
- INSERM UMR 1033, University of Lyon, Hôpital Edouard Herriot, Lyon, France
| | - Serge Ferrari
- Division of Bone Diseases, Department of Internal Medicine Specialties, Geneva University Hospital, Geneva, Switzerland
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Wu B, Zhang C, Chen B, Zhang L, Dai R, Wu X, Jiang Y, Liao E. Self-repair of rat cortical bone microdamage after fatigue loading in vivo. Int J Endocrinol 2013; 2013:321074. [PMID: 23662102 PMCID: PMC3639633 DOI: 10.1155/2013/321074] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 03/24/2013] [Indexed: 11/20/2022] Open
Abstract
Bone microdamage can be repaired through bone remodeling induced by loading. In this study, a loading device was developed for improved efficiency and the self-repair process of bone microdamage was studied in ovariectomized rats. First, four-point bending fixtures capable of holding two live rats simultaneously were designed. Rats were loaded and subjected to a sinusoidal wave for 10,000 cycles. They were then divided into four groups to evaluate time points from 1 to 4 weeks in the microdamage repair process. The loaded right ulna was used for microdamage parameter analysis, and the loaded right radius was tested for mechanical properties. In all groups, microdamage consisted primarily of microcracks, which were observed in bone surrounding the force-bearing point. The values of the microdamage parameters were significantly lower at 3 weeks than at 2 weeks. However, none of the differences in mechanical properties between any four groups were statistically significant. This study shows that the improved application of loading in the form of bending for double-rat simultaneous administration was practical and efficient. These results suggest that microdamage was repaired between 2 weeks to 3 weeks after fatigue damage and microdamage is a more sensitive index of bone quality than mechanical properties.
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Affiliation(s)
- Bo Wu
- Institute of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Chan Zhang
- Institute of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Bo Chen
- Institute of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Ling Zhang
- Institute of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Ruchun Dai
- Institute of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
- *Ruchun Dai:
| | - Xianping Wu
- Institute of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Yebin Jiang
- Department of Radiology, University of Michigan Hospitals, 1500 E Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Eryuan Liao
- Institute of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
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Moen MH, Holtslag L, Bakker E, Barten C, Weir A, Tol JL, Backx F. The treatment of medial tibial stress syndrome in athletes; a randomized clinical trial. Sports Med Arthrosc Rehabil Ther Technol 2012; 4:12. [PMID: 22464032 PMCID: PMC3352296 DOI: 10.1186/1758-2555-4-12] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 03/30/2012] [Indexed: 11/10/2022]
Abstract
BACKGROUND The only three randomized trials on the treatment of MTSS were all performed in military populations. The treatment options investigated in this study were not previously examined in athletes. This study investigated if functional outcome of three common treatment options for medial tibial stress syndrome (MTSS) in athletes in a non-military setting was the same. METHODS The study design was randomized and multi-centered. Physical therapists and sports physicians referred athletes with MTSS to the hospital for inclusion. 81 athletes were assessed for eligibility of which 74 athletes were included and randomized to three treatment groups. Group one performed a graded running program, group two performed a graded running program with additional stretching and strengthening exercises for the calves, while group three performed a graded running program with an additional sports compression stocking. The primary outcome measure was: time to complete a running program (able to run 18 minutes with high intensity) and secondary outcome was: general satisfaction with treatment. RESULTS 74 Athletes were randomized and included of which 14 did not complete the study due a lack of progress (18.9%). The data was analyzed on an intention-to-treat basis. Time to complete a running program and general satisfaction with the treatment were not significantly different between the three treatment groups. CONCLUSION This was the first randomized trial on the treatment of MTSS in athletes in a non-military setting. No differences were found between the groups for the time to complete a running program. TRIAL REGISTRATION CCMO; NL23471.098.08.
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Affiliation(s)
- Maarten Hendrik Moen
- Rehabilitation and Sports Medicine Department, University Medical Center Utrecht, Utrecht, Holland.
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Ozgürbüz C, Yüksel O, Ergün M, Işlegen C, Taskiran E, Denerel N, Karamizrak O. Tibial bone density in athletes with medial tibial stress syndrome: a controlled study. J Sports Sci Med 2011; 10:743-747. [PMID: 24149568 PMCID: PMC3761496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Accepted: 10/25/2011] [Indexed: 06/02/2023]
Abstract
Medial tibial stress syndrome (MTSS) is a common overuse injury of the lower extremity predominantly observed in weight bearing activities. Knowledge about the pathological lesions and their pathophysiology is still limited. Only a single study was found to have investigated tibial bone density in the pain region, revealing lower density in athletes with long standing (range, 5-120 month) MTSS. In a follow-up study, bone density was determined to return to normal levels after recovery. The purpose of the present study was to investigate tibial bone density in athletes with shorter MTSS history (range, 3-10 weeks). A total of 11 athletes (7 males, 4 females) diagnosed with medial tibial stress syndrome were included in the study. The control group consisted of 11 regularly exercising individuals (7 males, 4 females). Tibial, femoral and vertebral bone densities were measured by dual energy x-ray absorptiometry. Total calcium intake was calculated by evaluating detailed nutrition history. No statistically significant differences were found in the tibial, femoral and vertebral bone densities between the groups. No statistically significant difference was found among groups, considering for calcium intake. Tibial bone densities were not lower in athletes with MTSS of 5.0 weeks mean duration (range, 3-10 weeks) compared to the healthy control group. Longitudinal studies with regular tibial bone density measurements in heavily trained athletes are necessary to investigate tibial density alterations in MTSS developing athletes during the course of the symptoms. Key pointsTibial, femoral and vertebral bone densities were measured by dual energy x-ray absorptiometry.No differences were found between the MTSS group (MTSS history 3-10 weeks) and the healthy athletes group.
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Miller RA, Kreider J, Galecki A, Goldstein SA. Preservation of femoral bone thickness in middle age predicts survival in genetically heterogeneous mice. Aging Cell 2011; 10:383-91. [PMID: 21276183 DOI: 10.1111/j.1474-9726.2011.00671.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
To see whether age-related changes in bone could predict subsequent lifespan, we measured multiple aspects of femur size and shape at 4, 15, and 24 months of age in genetically heterogeneous mice. Mice whose cortical bone became thicker from 4 to 15 months, associated with preservation of the endosteal perimeter, survived longer than mice whose endosteal cavity expanded, at the expense of cortical bone, over this age range. Femur size at age 4 months was also associated with a difference in life expectancy: mice with larger bones (measured by length, cortical thickness, or periosteal perimeter) had shorter lifespans. Femur length, midlife change in cortical bone thickness, and midlife values of CD8 T memory cells each added significant power for longevity prediction. Mice in the upper half of the population for each of these three endpoints lived, on average, 103 days (12%) longer than mice with the opposite characteristics. Thus, measures of young adult bone dimensions, changes as a result of bone remodeling in middle age, and immunological maturation provide partially independent indices of aging processes that together help to determine lifespan in genetically heterogeneous mice.
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Affiliation(s)
- Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, USA.
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Zikan V. Bone health in patients with multiple sclerosis. J Osteoporos 2011; 2011:596294. [PMID: 21603140 PMCID: PMC3096310 DOI: 10.4061/2011/596294] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Accepted: 02/02/2011] [Indexed: 01/23/2023] Open
Abstract
Multiple sclerosis (MS) is a gait disorder characterized by acute episodes of neurological defects leading to progressive disability. Patients with MS have multiple risk factors for osteoporotic fractures, such as progressive immobilization, long-term glucocorticoids (GCs) treatment or vitamin D deficiency. The duration of motor disability appears to be a major contributor to the reduction of bone strength. The long term immobilization causes a marked imbalance between bone formation and resorption with depressed bone formation and a marked disruption of mechanosensory network of tightly connected osteocytes due to increase of osteocyte apoptosis. Patients with higher level of disability have also higher risk of falls that combined with a bone loss increases the frequency of bone fractures. There are currently no recommendations how to best prevent and treat osteoporosis in patients with MS. However, devastating effect of immobilization on the skeleton in patients with MS underscores the importance of adequate mechanical stimuli for maintaining the bone structure and its mechanical competence. The physical as well as pharmacological interventions which can counteract the bone remodeling imbalance, particularly osteocyte apoptosis, will be promising for prevention and treatment of osteoporosis in patients with MS.
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Affiliation(s)
- Vit Zikan
- Department of Internal Medicine 3, Faculty of Medicine 1, Charles University, 128 00 Prague, Czech Republic
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Rochefort GY, Pallu S, Benhamou CL. Osteocyte: the unrecognized side of bone tissue. Osteoporos Int 2010; 21:1457-69. [PMID: 20204595 DOI: 10.1007/s00198-010-1194-5] [Citation(s) in RCA: 169] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Accepted: 12/28/2009] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Osteocytes represent 95% of all bone cells. These cells are old osteoblasts that occupy the lacunar space and are surrounded by the bone matrix. They possess cytoplasmic dendrites that form a canalicular network for communication between osteocytes and the bone surface. They express some biomarkers (osteopontin, beta3 integrin, CD44, dentin matrix protein 1, sclerostin, phosphate-regulating gene with homologies to endopeptidases on the X chromosome, matrix extracellular phosphoglycoprotein, or E11/gp38) and have a mechano-sensing role that is dependent upon the frequency, intensity, and duration of strain. DISCUSSION The mechanical information transmitted into the cytoplasm also triggers a biological cascade, starting with NO and PGE(2) and followed by Wnt/beta catenin signaling. This information is transmitted to the bone surface through the canalicular network, particularly to the lining cells, and is able to trigger bone remodeling by directing the osteoblast activity and the osteoclastic resorption. Furthermore, the osteocyte death seems to play also an important role. The outcome of micro-cracks in the vicinity of osteocytes may interrupt the canalicular network and trigger cell apoptosis in the immediate surrounding environment. This apoptosis appears to transmit a message to the bone surface and activate remodeling. The osteocyte network also plays a recognized endocrine role, particularly concerning phosphate regulation and vitamin D metabolism. Both the suppression of estrogen following menopause and chronic use of systemic glucocorticoids induce osteocyte apoptosis. On the other hand, physical activity has a positive impact in the reduction of apoptosis. In addition, some osteocyte molecular elements like sclerostin, connexin 43, E11/gp38, and DKK1 are emerging as promising targets for the treatment of various osteo-articular pathologies.
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Affiliation(s)
- G Y Rochefort
- INSERM Research Unit 658, Centre Hospitalier Régional, 1 rue Porte Madeleine, 45 032 Orleans, France.
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