scholarly journals Limb- and tendon-specific Adamtsl2 deletion identifies a soft tissue mechanism modulating bone length

2018 ◽  
Author(s):  
Dirk Hubmacher ◽  
Stetson Thacker ◽  
Sheila M. Adams ◽  
David E. Birk ◽  
Ronen Schweitzer ◽  
...  

AbstractDisproportionate distal limb shortening is the hallmark of acromelic dysplasias. Among them, geleophysic dysplasia is a rare, frequently lethal condition characterized by severe short stature, musculoskeletal, cardiac, pulmonary, and skin anomalies. Geleophysic dysplasia results from dominant fibrillin-1 (FBN1) or recessive ADAMTSL2 mutations, suggesting a functional link between ADAMTSL2 and FBN1. Mice lacking ADAMTSL2 die at birth, precluding analysis of postnatal skeletal growth and mechanisms underlying the skeletal anomalies of geleophysic dysplasia. We show that Adamtsl2 is expressed in limb soft tissues, predominantly in tendon. Expression in developing bones is limited to their terminal cell layers that are destined to become articular cartilage and is absent in growth plate cartilage. Adamtsl2 conditional deletion in limb mesenchyme using Prxl-Cre led to an acromelic dysplasia, providing a suitable model for investigation of geleophysic dysplasia. Unexpectedly, conditional Adamtsl2 deletion using Scx-Cre, a tendon-specific deleter, also impaired skeletal growth. Specific morphogenetic anomalies were seen in Achilles tendon, along with FBN1 accumulation. Thus, ADAMTSL2, shown here to bind fibrillin microfibrils in vitro, limits fibrillin microfibril formation in tendons and promotes tendon growth. The findings suggest that reduced bone growth in geleophysic dysplasia results from external tethering by short tendons rather than intrinsic growth plate anomalies.

2021 ◽  
Vol 11 (17) ◽  
pp. 7786
Author(s):  
Jin Ah Ryuk ◽  
Hye Jin Kim ◽  
Joo Tae Hwang ◽  
Byoung Seob Ko

Allium fistulosum is a perennial plant species grown worldwide belonging to the family Liliaceae. In Korean medicine, it is referred to as Chongbaek (CB), and it is prescribed for symptoms associated with the common cold due to its antipyretic properties. This study examined the effects of aqueous (CBW) and 30% ethanol (CBE) extracts on bone growth using a calcium- and vitamin D-deficient animal model. In an in vitro experiment, the alkaline phosphate activities of the extracts were examined using MC3T3-E1 and MG63 cells, and both the aqueous and ethanolic extracts had significant alkaline phosphate activities. In vivo, a serum analysis indicated that the CB extracts promoted bone growth based on the osteogenic markers ALP, calcium, osteocalcin, and collagen type 1 and increased the bone mineral content (BMC), bone mineral density (BMD), and growth plate length. Overall, our results indicate that both CBW and CBE of A. fistulosum can be utilized to facilitate bone growth and increase BMD in children and adolescents by lengthening the growth plate without adverse side effects, such as metabolic disorders or the release of obesity-inducing hormones.


1994 ◽  
Vol 72 (10) ◽  
pp. 2629-2634 ◽  
Author(s):  
José M. Peralta ◽  
Andrew M. Arnold ◽  
W. Bruce Currie ◽  
Michael L. Thonney

2019 ◽  
Vol 2 (2) ◽  
pp. e201800254 ◽  
Author(s):  
Sehee Choi ◽  
Hyun-Yi Kim ◽  
Pu-Hyeon Cha ◽  
Seol Hwa Seo ◽  
Chulho Lee ◽  
...  

Longitudinal bone growth ceases with growth plate senescence during puberty. However, the molecular mechanisms of this phenomenon are largely unexplored. Here, we examined Wnt-responsive genes before and after growth plate senescence and found that CXXC finger protein 5 (CXXC5), a negative regulator of the Wnt/β-catenin pathway, was gradually elevated with reduction of Wnt/β-catenin signaling during senescent changes of rodent growth plate. Cxxc5−/− mice demonstrated delayed growth plate senescence and tibial elongation. As CXXC5 functions by interacting with dishevelled (DVL), we sought to identify small molecules capable of disrupting this interaction. In vitro screening assay monitoring CXXC5–DVL interaction revealed that several indirubin analogs were effective antagonists of this interaction. A functionally improved indirubin derivative, KY19382, elongated tibial length through delayed senescence and further activation of the growth plate in adolescent mice. Collectively, our findings reveal an important role for CXXC5 as a suppressor of longitudinal bone growth involving growth plate activity.


2021 ◽  
pp. 088532822199989
Author(s):  
Christopher Erickson ◽  
Michael Stager ◽  
Michael Riederer ◽  
Karin A Payne ◽  
Melissa Krebs

The growth plate is a cartilage tissue near the ends of children’s long bones and is responsible for bone growth. Injury to the growth plate can result in the formation of a ‘bony bar’ which can span the growth plate and result in bone growth abnormalities in children. Biomaterials such as chitosan microgels could be a potential treatment for growth plate injuries due to their chondrogenic properties, which can be enhanced through loading with biologics. They are commonly fabricated via an emulsion method, which involves solvent rinses that are cytotoxic. Here, we present a high throughput, non-cytotoxic, non-emulsion-based method to fabricate chitosan–genipin microgels. Chitosan was crosslinked with genipin to form a hydrogel network, and then pressed through a syringe filter using mesh with various pore sizes to produce a range of microgel particle sizes. The microgels were then loaded with chemokines and growth factors and their release was studied in vitro. To assess the applicability of the microgels for growth plate cartilage regeneration, they were injected into a rat growth plate injury. They led to increased cartilage repair tissue and were fully degraded by 28 days in vivo. This work demonstrates that chitosan microgels can be fabricated without solvent rinses and demonstrates their potential for the treatment of growth plate injuries.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Hye Kyung Kim ◽  
Myung-Gyou Kim ◽  
Kang-Hyun Leem

The aim of this study was to compare the effectiveness of velvet antler (VA) from different sections for promoting longitudinal bone growth in growing rats. VA was divided into upper (VAU), middle (VAM), and basal sections (VAB). An in vivo study was performed to examine the effect on longitudinal bone growth in adolescent rats. In addition, in vitro osteogenic activities were examined using osteoblastic MG-63 cells. VA promoted longitudinal bone growth and height of the growth plate in adolescent rats. Bone morphogenetic protein-2 (BMP-2) in growth plate of VA group was highly expressed compared with control. The anabolic effect of VA on bone was further supported by in vitro study. VA enhanced the proliferation, differentiation, and mineralization of MG-63 cells. The mRNA expressions of osteogenic genes such as collagen, alkaline phosphatase, and osteocalcin were increased by VA treatment. These effects of in vivo and in vitro study were decreased from upper to basal sections of VA. In conclusion, VA treatment promotes longitudinal bone growth in growing rats through enhanced BMP-2 expression, osteogenic activities, and bone matrix gene expressions. In addition, present study provides evidence for the regional differences in the effectiveness of velvet antler for longitudinal bone growth.


2019 ◽  
Vol 84 (9) ◽  
pp. 951-960
Author(s):  
Jelena Gvozdenovic-Jeremic ◽  
Ekaterina Vert-Wong ◽  
Ljiljana Mojovic

Pathological formation of bone in non-skeletal soft tissues or heterotopic ossification (HO), for which there is currently no effective treatment, is considered to be mediated by activation of Hedgehog (Hh) signaling pathway. Moreover, the biochemical mechanism of this pathological process is not fully understood. Here, we tested the efficacy of three chemical inhibitors of the Hh signaling pathway, arsenic trioxide (ATO), lovastatin (Lov) and cholecalciferol (Vitamin D) to hamper differentiation of mesenchymal stem cells (MSC) into osteoblasts or osteogenesis. Each of the three Hh inhibitors potently decreased alkaline phosphatase activity, suggesting effective suppression of osteogenic activity in Hh-impaired MSC. Gene expression analysis revealed a significant reduction in mRNA levels of chief Hh signaling marker, Gli1, following administration of Hh small molecule inhibitors. A functional link between Hedgehog and osteogenesis in native MSC cells is further established in studies involving the mix of three Hh inhibitors acting at different checkpoints of the Hh signaling pathway. Thus, a combination of small molecule inhibitors of the Hh pathway at their lower concentrations could be a novel approach for HO prophylaxis with increased efficacy and potentially reduced side effects.


2020 ◽  
Author(s):  
Leia C. Shuhaibar ◽  
Nabil Kaci ◽  
Jeremy R. Egbert ◽  
Léa Loisay ◽  
Giulia Vigone ◽  
...  

ABSTRACTActivating mutations in fibroblast growth factor receptor 3 (FGFR3) and inactivating mutations in the natriuretic peptide receptor 2 (NPR2) guanylyl cyclase both result in decreased production of cyclic GMP (cGMP) in chondrocytes and severe short stature, causing achondroplasia (ACH) and acrosomelic dysplasia type Maroteaux, respectively. Previously we showed that an NPR2 agonist BMN-111 (vosoritide) increases bone growth in mice mimicking ACH (Fgfr3Y367C/+), and that in control growth plate chondrocytes, FGFR3 signaling decreases NPR2 activity by dephosphorylating the NPR2 protein. Here we tested whether a phosphatase inhibitor (LB-100) could enhance bone growth in ACH. In ex vivo imaging experiments using a FRET sensor to measure cGMP production in chondrocytes of living tibias from newborn mice, LB-100 counteracts the FGF-induced dephosphorylation and inactivation of NPR2. In ex vivo experiments with Fgfr3Y367C/+ mice, LB-100 in combination with BMN-111 increases the rate of femur growth by ∼25% vs BMN-111 alone, restores chondrocyte terminal differentiation, increases the proliferative growth plate area of the femur, and reduces the activity of the MAP kinase pathway. Our results provide a proof of concept that a phosphatase inhibitor could be used together with an NPR2 agonist to enhance cGMP production as a therapy for ACH.GRAPHICAL ABSTRACT


Author(s):  
David B. Allen ◽  
Nadia Merchant ◽  
Bradley S. Miller ◽  
Philippe F. Backeljauw

Abstract Background: Longitudinal bone growth is regulated by multiple endocrine signals (e.g. growth hormone, insulin-like growth factor I, estrogen, androgen) and local factors (e.g. fibroblast growth factors and their receptors and the C-natriuretic peptide/NPR-2 pathway). Summary: Abnormalities in both endocrine and local regulation of growth plate physiology cause many disorders of human skeletal growth. Knowledge of these pathways creates therapeutic potential for sustaining or even augmenting linear growth. Key message: During the past four decades, advances in understanding growth plate physiology have been accompanied by development and implementation of growth-promoting treatments that have progressed in both efficacy and specificity of action. This paper reviews the history and continuing evolution of growth plate therapeutics.


2005 ◽  
Vol 186 (1) ◽  
pp. 241-249 ◽  
Author(s):  
Ola Nilsson ◽  
Robert D Mitchum ◽  
Lenneke Schrier ◽  
Sandra P Ferns ◽  
Kevin M Barnes ◽  
...  

The overall body size of vertebrates is primarily determined by longitudinal bone growth at the growth plate. With age, the growth plate undergoes programmed senescence, causing longitudinal bone growth to slow and eventually cease. Indirect evidence suggests that growth plate senescence occurs because stem-like cells in the growth plate resting zone have a finite proliferative capacity that is gradually exhausted. Similar limits on replication have been observed when many types of animal cells are placed in cell culture, an effect known as the Hayflick phenomenon. However, we found that the number of population doublings of rabbit resting zone chondrocytes in culture did not depend on the age of the animal from which the cells were harvested, suggesting that the mechanisms limiting replicative capacity of growth plate chondrocytes in vivo are distinct from those in vitro. We also observed that the level of DNA methylation in resting zone chondrocytes decreased with age in vivo. This loss of methylation appeared to occur specifically with the slow proliferation of resting zone chondrocytes in vivo and was not observed with the rapid proliferation of proliferative zone chondrocytes in vivo (i.e. the level of DNA methylation did not change from the resting zone to the hypertrophic zone), with proliferation of chondrocytes in vitro, or with growth of the liver in vivo. Thus, the overall level of DNA methylation decreases during growth plate senescence. This finding is consistent with the hypothesis that the mechanism limiting replication of growth plate chondrocytes in vivo involves loss of DNA methylation and, thus, loss of DNA methylation might be a fundamental biological mechanism that limits longitudinal bone growth in mammals, thereby determining the overall adult size of the organism.


2019 ◽  
Vol 51 (9) ◽  
pp. 1-10
Author(s):  
Sehee Choi ◽  
Pu-Hyeon Cha ◽  
Hyun-Yi Kim ◽  
Kang-Yell Choi

Abstract Researchers have shown increased interest in determining what stimulates height. Currently, many children undergo precocious puberty, resulting in short stature due to premature closure of the growth plate. However, the current approach for height enhancement is limited to growth hormone treatment, which often results in side effects and clinical failure and is costly. Although recent studies have indicated the importance of paracrine signals in the growth plate for longitudinal bone growth, height-stimulating agents targeting the signaling pathways involved in growth plate maturation remain unavailable in the clinic. The Wnt/β-catenin pathway plays a major role in the maturation of growth plate chondrocytes. In this study, by using an ex vivo tibial culture system, we identified indirubin-3′-oxime (I3O) as a compound capable of enhancing longitudinal bone growth. I3O promoted chondrocyte proliferation and differentiation via activation of the Wnt/β-catenin pathway in vitro. Intraperitoneal injection of I3O in adolescent mice increased growth plate height along with incremental chondrocyte maturation. I3O promoted tibial growth without significant adverse effects on bone thickness and articular cartilage. Therefore, I3O could be a potential therapeutic agent for increasing height in children with growth retardation.


Sign in / Sign up

Export Citation Format

Share Document