After the articular cartilage injury, the metabolic level is increased during the progressive degeneration, the chondrocytes secrete a variety of inflammatory factors, and the original cell phenotype is gradually changed. For a long time, a large number of researchers have done a lot of researches to promote anabolism of chondrocytes and to maintain the stability of chondrocyte phenotype. There are many molecular signaling pathways involved in the process of promoting cartilage repair. This review focuses on the key signaling molecules in articular cartilage repair, such as transforming growth factor-beta and bone morphogenetic protein, and reveals their roles in the process of cartilage injury and repair, so that researchers in related fields can understand the molecular mechanism of cartilage injury and repair widely and deeply. Based on this, they may find promising targets and biological methods for the treatment of cartilage injury.
Bone Morphogenetic Proteins ; physiology ; Cartilage, Articular ; growth & development ; injuries ; Chondrocytes ; physiology ; Humans ; Regeneration ; Signal Transduction ; Transforming Growth Factor beta ; physiology

The bone morphogenetic protein (BMP) family is an important factor in the regulation of cell ular life activities and in the development of almost all tissues. BMP-mediated signaling plays an important role in tooth root development, which is a part of tooth development. Epithelial and mesenchymal interactions are involved in tooth root development, but the BMP signaling pathway has a different effect on tooth root development in epithelial and mesenchymal. This review summarizes the advances of BMP signaling in tooth root development.
Bone Morphogenetic Protein 2 ; Bone Morphogenetic Protein 7 ; Bone Morphogenetic Proteins ; physiology ; Odontogenesis ; Signal Transduction ; Tooth ; Tooth Root ; growth & development

Animals ; Biomechanical Phenomena ; Bone Development ; Bone Remodeling ; Bone and Bones ; injuries ; Fracture Healing ; physiology ; Fractures, Bone ; pathology

OBJECTIVETo investigate the effect of electronspun PLGA/HAp/Zein scaffolds on the repair of cartilage defects.

METHODSThe PLGA/HAp/Zein composite scaffolds were fabricated by electrospinning method. The physiochemical properties and biocompatibility of the scaffolds were separately characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), and fourier transform infrared spectroscopy (FTIR), human umbilical cord mesenchymal stem cells (hUC-MSCs) culture and animal experiments.

RESULTSThe prepared PLGA/HAp/Zein scaffolds showed fibrous structure with homogenous distribution. hUC-MSCs could attach to and grow well on PLGA/HAp/Zein scaffolds, and there was no significant difference between cell proliferation on scaffolds and that without scaffolds (P>0.05). The PLGA/HAp/Zein scaffolds possessed excellent ability to promote in vivo cartilage formation. Moreover, there was a large amount of immature chondrocytes and matrix with cartilage lacuna on PLGA/HAp/Zein scaffolds.

CONCLUSIONThe data suggest that the PLGA/HAp/Zein scaffolds possess good biocompatibility, which are anticipated to be potentially applied in cartilage tissue engineering and reconstruction.

Animals ; Biocompatible Materials ; Bone Development ; physiology ; Cartilage ; growth & development ; Cells, Cultured ; Durapatite ; chemistry ; Female ; Humans ; Lactic Acid ; chemistry ; Male ; Mesenchymal Stromal Cells ; physiology ; Polyglycolic Acid ; chemistry ; Regeneration ; physiology ; Tissue Scaffolds ; chemistry ; Young Adult ; Zein ; chemistry

OBJECTIVETo explore the mechanism and effect of maternal high-fat diet before and during pregnancy on bone growth of neonatal offspring rats.

METHODSForty female Sprague-Dawley rats were divided into high-fat diet and control groups (n=20) that were fed with 35% high-fat diet and standard chow, respectively. After 8 weeks, 8 female rats from each group were sacrificed for liver pathological examinations and the other female rats were mated with male rats and fed continuously with 35% high-fat diet and standard chow throughout gestation, respectively. The body lengths (from apex nasi to end of tail) of the offspring rats from both groups were measured within 24 hours after birth. Enzyme-linked immunosorbent assay was used to detect serum insulin-like growth factor (IFG-I) levels. Liver pathological changes were observed under a light microscope. The expression of insulin receptor substrate 1 (IRS-1) and phosphorylation IRS-1 (Phospho-IRS-1) in tibia and femur samples were detected by immunohistochemistry. The expression of mitogen-activated protein kinase (MAPK) and phosphorylation MAPK (Phospho-MAPK), phosphatidylinositol 3-kinase (PI3K) and phosphorylation PI3K (Phospho-PI3K), protein kinase B (AKT1) and phosphorylation AKT1 (Phospho-AKT1) in tibia and femur samples were detected by Western blot.

RESULTSThe offspring rats from the high-fat diet group showed a significant shorter body length compared with those from the control group (P<0.05). The level of serum IGF-I in offspring rats from the high-fat diet group decreased by 20.1% in comparison to those from the control group, but there was no significant difference between the two groups (P>0.05). Fatty degeneration was found in livers of both high-fat diet-fed maternal rats and their offspring rats under a light microscope. There were no significant differences in IRS-1 and Phospho-IRS-1 expression in chondrocytes of tibia and femur samples between the offspring rats of the two groups (P>0.05). The protein expression of MAPK in chondrocytes of tibia and femur samples of offspring rats from the high-fat diet group was higher than that from the control group (P<0.05). There were no significant differences of PI3K and AKT1/Phospho-AKT1 between the offspring rats of the two groups (P>0.05).

CONCLUSIONSA maternal high-fat diet before and during pregnancy may affect the bone growth of offspring rats in utero, which is possibly associated with the decreased IGF-I level. However, further study on the exact mechanism of IGF-I on the bone growth is needed.

Animals ; Bone Development ; Diet, High-Fat ; Female ; Insulin-Like Growth Factor I ; analysis ; Liver ; pathology ; MAP Kinase Signaling System ; Maternal Nutritional Physiological Phenomena ; Phosphatidylinositol 3-Kinases ; physiology ; Pregnancy ; Proto-Oncogene Proteins c-akt ; physiology ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To realize the automated assessment of the levels of epiphysis of distal radius and ulna by support vector machine (SVM). METHODS: The X-ray films of the left wrist joints were taken from 140 teenagers aged from 11 to 19 years old as training samples. The levels of epiphysis of distal radius and ulna were divided into five developmental levels. Each level contained 28 samples. Another 35 cases were selected as independent verifying samples. SVM classification models of the five developmental levels of epiphysis of distal radius and ulna were established. The internal cross validation was made by leave one out cross validation (LOOCV), while the external validation was made by histogram of oriented gradient (HOG), and then the accuracy (PA) of testing results was calculated, respectively. RESULTS: The PA of SVM, LOOCV and HOG of distal radius epiphyseal level were 100%, 78.6%, and 82.8%, respectively; whereas the PA of SVM, LOOCV and HOG of distal ulna epiphyseal level were 100.0%, 80.0% and 88.6%, respectively. CONCLUSION The SVM-based automatic models of the growth stage of distal ra- dius and ulna appear to have certain feasibility, and may provide a foundation for software development of bone age assessment by forensic medicine.
Adolescent ; Bone Development/physiology* ; Child ; Epiphyses/growth & development* ; Female ; Humans ; Image Processing, Computer-Assisted/methods* ; Male ; Radius/growth & development* ; Support Vector Machine ; Ulna/growth & development* ; Wrist/growth & development* ; Wrist Joint/growth & development* ; Young Adult

Formation of the periodontium begins following onset of tooth-root formation in a coordinated manner after birth. Dental follicle progenitor cells are thought to form the cementum, alveolar bone and Sharpey's fibers of the periodontal ligament (PDL). However, little is known about the regulatory morphogens that control differentiation and function of these progenitor cells, as well as the progenitor cells involved in crown and root formation. We investigated the role of bone morphogenetic protein-2 (Bmp2) in these processes by the conditional removal of the Bmp2 gene using the Sp7-Cre-EGFP mouse model. Sp7-Cre-EGFP first becomes active at E18 in the first molar, with robust Cre activity at postnatal day 0 (P0), followed by Cre activity in the second molar, which occurs after P0. There is robust Cre activity in the periodontium and third molars by 2 weeks of age. When the Bmp2 gene is removed from Sp7(+) (Osterix(+)) cells, major defects are noted in root, cellular cementum and periodontium formation. First, there are major cell autonomous defects in root-odontoblast terminal differentiation. Second, there are major alterations in formation of the PDLs and cellular cementum, correlated with decreased nuclear factor IC (Nfic), periostin and α-SMA(+) cells. Third, there is a failure to produce vascular endothelial growth factor A (VEGF-A) in the periodontium and the pulp leading to decreased formation of the microvascular and associated candidate stem cells in the Bmp2-cKO(Sp7-Cre-EGFP). Fourth, ameloblast function and enamel formation are indirectly altered in the Bmp2-cKO(Sp7-Cre-EGFP). These data demonstrate that the Bmp2 gene has complex roles in postnatal tooth development and periodontium formation.
Actins ; analysis ; Activating Transcription Factor 2 ; genetics ; Age Factors ; Ameloblasts ; pathology ; Amelogenesis ; genetics ; Animals ; Bone Morphogenetic Protein 2 ; genetics ; Cell Adhesion Molecules ; analysis ; Cell Differentiation ; genetics ; Cementogenesis ; genetics ; Dental Cementum ; pathology ; Dental Pulp ; blood supply ; Fluorescent Dyes ; Green Fluorescent Proteins ; Male ; Mice ; Mice, Knockout ; Microvessels ; pathology ; Molar ; growth & development ; Molar, Third ; growth & development ; NFI Transcription Factors ; analysis ; Odontoblasts ; pathology ; Odontogenesis ; genetics ; Periodontal Ligament ; growth & development ; Sp7 Transcription Factor ; Stem Cells ; physiology ; Tooth Root ; growth & development ; Transcription Factors ; genetics ; Vascular Endothelial Growth Factor A ; analysis ; Zinc Fingers ; genetics

The purpose of the present study was to observe the structure and functional change of the bone-coating-prosthesis interface in vivo and to evaluate the histocompatibility of self-made prosthetic femoral components in the body and the degree of their bonding with the surrounding bone tissues as well as their stability. Six mature beagle dogs underwent bilateral hip replacement with prosthetic femur components. Three groups were established in terms of different coating of prothesis (four joints in each group): atmosphere (A) plasma-sprayed pure titanium (Ti) prosthetic joint with hydroxyapatite (HA) coating (HA+Ti+A group); vacuum (V) plasma-sprayed pure Ti prosthetic joint with HA coating (HA+Ti+V group); vacuum plasma-sprayed pure Ti prosthetic joint with Ti-HA stepped coating (Ti+HAG+Ti+V group). The hip joints were functionally evaluated, and subjected to X-ray examination, biomechanics inspection, and histological examination. As a result, X-ray imaging revealed all prosthetic joints were in a good location and no dislocation of joint was found. Shear strength of interface was significantly higher in Ti+HAG+Ti+V group than in HA+Ti+V group (P<0.05) and HA+Ti+A group (P<0.05) at 28th week. Histological examination showed the amount of newborn bone in Ti+HAG+Ti+V group was more than in HA+Ti+V group and HA+Ti+A group after 28 weeks. It was suggested that vacuum plasma-sprayed pure Ti prosthetic joint with TI-HA stepped coating could improve the bonding capacity of bone-prosthesis, enhance the stability of prosthesis, and increase the fixion of prosthetic femoral components because of better bone growth. This new type of biological material in prosthetic femoral components holds promises for application in clinical practice.
Animals ; Biomechanical Phenomena ; drug effects ; physiology ; Bone Development ; drug effects ; physiology ; Coated Materials, Biocompatible ; pharmacology ; Dogs ; Durapatite ; pharmacology ; Femur ; drug effects ; physiology ; Prostheses and Implants ; Titanium ; pharmacology ; Vacuum

In mammals, ovarian follicle is made of an oocyte with its surrounding granulosa cells and theca cells. Follicular growth and development is a highly coordinated programmable process, which guarantees the normal oocyte maturation and makes it having the fertilizing capacity. The paracrine and autocrine between oocytes and granulosa cells are essential for the follicular development to provide a suitable microenvironment. Phosphatidylinositol-3 kinase /protein kinase B is one of these important regulatory signaling pathways during this developmental process, and bone morphogenetic protein-15 an oocyte-specific secreted signal molecule, which regulates the follicular development by paracrine in the mammalian ovary. The present article overviewed the role of phosphatidylinositol-3 kinase / protein kinase B signaling during the follicular development based on our previous investigation about protein kinase B /forkhead transcription factor forkhead family of transcription factors -3a, and then focused on the regulatory effects of bone morphogenetic protein-15, as a downstream signal molecule of phosphatidylinositol-3 kinase / forkhead family of transcription factors -3a pathway, on ovarian follicular development, which helped to further understand the molecular mechanism regulating the follicular development and to treat ovarian diseases like infertility.
Animals ; Bone Morphogenetic Protein 15 ; physiology ; Female ; Granulosa Cells ; physiology ; Humans ; Mammals ; Ovarian Follicle ; growth & development ; Ovary ; growth & development ; Phosphatidylinositol 3-Kinase ; physiology ; Proto-Oncogene Proteins c-akt ; physiology ; Signal Transduction

OBJECTIVE: To estimate the chronological age of Han teenagers in Sichuan by the epiphyses development characteristics of iliac crest and ischial tuberosity in X-ray digital images. METHODS: According to TW2 classification principle, combining with the age range of our subjects and epiphyses development regularity, the degree of epiphyses development of iliac crest and ischial tuberosity had been divided into 8 grades (0-7) and 7 grades (0-6), respectively. Based on the degrees, the pelvic X-rays digital images of 691 samples of 16-20 aged teenagers were read and statistically analyzed by SPSS 19.0 software. The multiple linear regression equation was established by skeletal age (Y), development degree of iliac crest epiphyses (X1) and ischial tuberosity epiphyses (X2). RESULTS: There were no statistical differences between two sides of epiphyses development of iliac crest and ischial tuberosity (P>0.05). There were no statistical difference between genders (P>0.05). The re-substitution method of the samples showed that the accuracy of equation as Y=15.269+0.444X1+0.236 X2 was high. The result of the re-substitution method showed a high accuracy of the equation. CONCLUSION The multiple linear regression equation could be used to identify the skeletal age for providing the scientific basis to identify the 18-year-old Han population in Sichuan.
Adolescent ; Age Determination by Skeleton/methods* ; Age Factors ; Asian People/ethnology* ; Bone Development/physiology* ; China/ethnology* ; Epiphyses/diagnostic imaging* ; Female ; Forensic Anthropology/methods* ; Humans ; Ilium/diagnostic imaging* ; Ischium/diagnostic imaging* ; Linear Models ; Male ; Pelvis/diagnostic imaging* ; Tomography, X-Ray Computed ; Young Adult