Maximizing peak bone mass is advocated as a way to prevent osteoporosis. To evaluate the peak bone mass and the affecting factors in Korean women, we analyzed bone stiffness in 116 middle school students, 118 high school students and 115 female college students by using the Achilles densitometer (Lunar Corporation). Peak bone stiffness of Korean women was relatively lower than that of white women (94% of white women) and a rapid rise of bone stiffness was observed in those subjects 3-4 years after menarche. In adolescent females without menstruation, the bone stiffness was lower than that of adolescent girls with menstruation. The factors affecting the peak bone mass was similar to the risk factors of post menopausal osteoporosis: menstruation status, calcium intake and physical activity. The amount of calcium intake in Korean girls at the critical age (3-4 years after menarche) was lower than the RDA (requirement of daily allowance) at this age. To improve any program aimed at maximizing peak bone mass, further intensive study will be required to evaluate some other common factors affecting peak bone mass in Korean.
Adolescent ; Adult ; Aging/physiology ; *Bone Density ; Bone and Bones/drug effects/physiology ; Calcium, Dietary/pharmacology ; Child ; Elasticity ; Female ; Human ; Korea ; Menarche

Objective: To evaluate the application of mechanically reinforced 45S5 Bioglass^®-derived glass ceramic porous scaffolds for repair of bone defect in rabbits. Methods: The BG-ZnB powders were added into the 45S5 Bioglass^® powder/paraffin microsphere mixtures and were sintered at 900℃ to obtain porous scaffolds with highly bioactive BG-ZnB of 0%, 2% or 4% of mass fraction (denoted as 45S5/ZnB0, 45S5/ZnB2, 45S5/ZnB4). Phase composition, porosity and compression properties of three kinds of as-sintered scaffolds were characterized by X-ray analysis, mercury porosimetry, and mechanical test. Thirty-six male New Zealand rabbits with critical-sized femoral bone defects were randomly divided into three groups (45S5/ZnB0 group, 45S5/ZnB2 group and 45S5/ZnB4 group, 12 for each), and were implanted with three kinds of porous scaffolds respectively. X-ray, micro-CT three-dimensional reconstruction and tissue slice staining were used to detected the efficiency of bone regeneration at 6 and 16 weeks after operation. The growth of newly formed bone was observed using HE, Masson staining and EnVision method. Results: Phase compositions of 45S5/ZnB2 and 45S5/ZnB4 were the same with 45S5/ZnB0, but the average pore size and porosity of the scaffolds were decreased with the increase of BG-ZnB content. 45S5/ZnB2 and 45S5/ZnB4 scaffolds exhibited higher compressive strength, osteogenesis and trabecular density than those of the 45S5/ZnB0 scaffold (all P<0.05). With the mechanical reinforcement of BG-ZnB increased, the content of new bone, collagen type I and osteocalcin increased. Conclusion: Low-melt BG-ZnB-assisted sintering is a promising approach to improve the mechanical strength of 45S5 Bioglass^®.
Animals ; Bone and Bones ; drug effects ; physiology ; Ceramics ; chemistry ; Glass ; Male ; Porosity ; Rabbits ; Tissue Scaffolds ; chemistry

Bones are stained into red color with feeding madder, but we do not know whether the fed madder can change the bone biomechanical properties and bone mineral contents in animals. In this research, we established a rat model with feeding madder. The bone biomechanical properties were detected by universal material mechanics, bone mineral contents were detected by inductively coupled plasma mass spectrometry and spectrometer, and red color material in bone was analyzed by high performance liquid chromatography. The results showed that bone biomechanical parameters in femur diaphysis in the 10% and 15% group rats were significantly higher than those in the control group after feeding madder for 6 months. The level of calcium, magnesium and zinc in femur diaphysis in 10% and 15% group rats were higher than those in the control group after feeding madder for 6 months. However, it was shown that the kidney congestion and hyperemia and the level of blood urea nitrogen and creatinine in the 15% group rats were significantly different compared to those in the control group rats after feeding madder for 6 months. The red colored material in bone is related to alizarin analyzed with high-performance liquid chromatography. The conclusion could be drawn that feeding 10% madder in diet was not toxic to the rats fed for 6 months, and it could improve bone biomechanical properties and increase bone mineral elements.
Animals ; Anthraquinones ; toxicity ; Biomechanical Phenomena ; Bone Density ; Bone and Bones ; drug effects ; physiology ; Calcium ; Femur ; Magnesium ; Rats ; Zinc

Growth Hormone (GH) is an important and powerful metabolic hormone that is secreted in a pulsatile pattern from cells in the anterior pituitary, influenced by several normal and pathophysiological conditions. Human GH was first isolated in the 1950s and human derived cadaveric GH was initially used to treat patients with GH deficiency. However, synthetic recombinant GH has been widely available since the mid-1980s and the advent of this recombinant GH boosted the abuse of GH as a doping agent. Doping with GH is a well-known problem among elite athletes and among people training at gyms, but is forbidden for both medical and ethical reasons. It is mainly the anabolic and, to some extent, the lipolytic effects of GH that is valued by its users. Even though GH's rumour as an effective ergogenic drug among athletes, the effectiveness of GH as a single doping agent has been questioned during the last few years. There is a lack of scientific evidence that GH in supraphysiological doses has additional effects on muscle exercise performance other than those obtained from optimised training and diet itself. However, there might be synergistic effects if GH is combined with, for example, anabolic steroids, and GH seems to have positive effect on collagen synthesis. Regardless of whether or not GH doping is effective, there is a need for a reliable test method to detect GH doping. Several issues have made the development of a method for detecting GH doping complicated but a method has been presented and used in the Olympics in Athens and Turin. A problem with the method used, is the short time span (24-36 hours) from the last GH administration during which the test effectively can reveal doping. Therefore, out-of-competition testing will be crucial.However, work with different approaches to develop an alternative, reliable test is ongoing.
Body Composition ; Bone and Bones ; drug effects ; Doping in Sports ; Growth Hormone ; adverse effects ; pharmacology ; physiology ; Humans ; Lipolysis ; Muscle, Skeletal ; drug effects ; physiology

Melanocortin is the downstream mediator of leptin signaling and absence of leptin signaling in ob/ob and db/db mice revealed the enhancement of bone formation through the central regulation. While alpha-melanocyte-stimulating hormone (alpha MSH) inhibits the secretion of interleukin-1 alpha and tumor necrosis factor-alpha from the inflammatory cells, alpha MSH can also enhance clonal expansion of pro B cells linked to stimulation of osteoclastogenesis. Therefore, we tested the effect of melanocortin on bones. alpha MSH analogues [6His] alpha MSH-ND and [6Asn] alpha MSH-ND were synthesized and the radio-ligand receptor binding- and cyclic AMP generating activity were analyzed in China Hamster Ovary cell line over- expressing melanocortin receptors. The EC50 of [6His] alpha MSH-ND measured from melanocortin-1, 3, 4 and 5 receptors were 0.008 0.0045, 1.523 0.707, 0.780 0.405, and 250.320 42.234 nM, respectively, and the EC50 of [6Asn] alpha MSH-ND were 16.8 6.94, 271.8 21.95, 8.0 1.21, and 1132.5 635.46 nM, respectively. Four weeks after the subcutaneous injection of the analogues, the body weights in the [6His] alpha MSH-ND and the [6Asn] alpha MSH-ND treated groups (346.0 20.63 g vs. 350.0 13.57 g) were lower than that of the vehicle treated group (375.8 17.31 g, p 0.05). There was no difference in the total femoral BMD measured by dual x-ray absorptiometry among the three groups. Among the three groups, there were no differences in the total numbers of crystal violet positive- or alkaline phosphatase positive colonies, in the expression of Receptor Activator of Nuclear Factor Kappa-B ligand on the tibia and the total number of multinucleated osteoclast-like cells differentiated from primary cultured bone marrow cells. From the above results, no evidence of bone gain or loss was found after treatment of the alpha MSH analogues peripherally.
Animal ; Body Weight/drug effects ; Bone and Bones/*drug effects ; CHO Cells ; Cyclic AMP/biosynthesis ; Eating/drug effects ; Hamsters ; Male ; Osteoblasts/drug effects/physiology ; Osteoclasts/drug effects/physiology ; Rats ; Rats, Sprague-Dawley ; Receptors, Corticotropin/physiology ; alpha-MSH/analogs & derivatives/*pharmacology

OBJECTIVETo compare the effects of icariin (ICA) and genistein (GEN) on rats bone peak mass and thus screen for a drug that can more effectively prevent osteoporosis.

METHODSTotally 36 one-month SD rats were randomly divided into three groups: ICA group [25 mg/(kg·d), intragastric administration], GEN group [10 mg/(kg·d), intragastric administration], and control group (fed with equal volume of distilled water). The body weight was monitored weekly and the bone mineral density of total body was measured monthly. All rats were sacrificed three months later. The femoral bone mineral density and the serum levels of osteocalcin and anti-tartaric acid phosphatase 5b, N-terminal propeptide of type 1 procollagen, and C-terminal propeptide of type 1collagen were measured. The bone microarchitectures were analyzed with micro-CT and the bone biomechanics properties were tested with universal material machine.

RESULTSThe body weight and organ index showed no significant difference among these three groups(P>0.05). No obvious pathological change was found. The bone mineral density was also not significantly different in the first and second months; however, in the third months, the ICA group had significant higher bone mineral density for both total body and femur than those in the control and GEN group (P<0.05). The same trends were found for both femur bone mineral density and whole-body bone mineral density (P<0.05). The ICA group also had significantly higher serum levels of osteocalcin (P<0.05) and lower level of anti-tartaric acid phosphatase 5b(P<0.05). Besides, rats in the ICA group had significantly larger bone volume/tissue volume, trabecular thickness, and trabecular number than the control group, whereas the trabecular spacing and model coefficients were signicantly lower(all P<0.05), which, however, were not significantly different between ICA group and GEN group (P>0.05). Femoral maximum load, Youg's modulus, and yield load were significantly higher in these two groups than in the control group (P<0.05), which, again, were not significantly different between ICA group and GEN group (P>0.05).

CONCLUSIONOrally administered ICA is more efficient than GEN in inhibiting resorption and promoting bone formation, and thus can dramatically improve the peak bone mineral density and bone quality.

Animals ; Bone Density ; drug effects ; Bone and Bones ; drug effects ; physiology ; Female ; Flavonoids ; pharmacology ; Genistein ; pharmacology ; Osteoporosis ; prevention & control ; Rats ; Rats, Sprague-Dawley

Animals ; Bone and Bones ; cytology ; Cell Differentiation ; Mesenchymal Stromal Cells ; drug effects ; physiology ; Neurons ; physiology ; Plant Extracts ; pharmacology ; Rats ; Salvia miltiorrhiza ; chemistry

OBJECTIVETo explore the preparative method and study the degradation characteristics of bone repair composite of DL-polylactic acid (PDLLA)/hydroxyapatite(HA)/decalcifying bone matrix (DBM) in vitro.

METHODSAn emulsion blend method was developed to prepare the composite of PDLLA/HA/DBM in weight ratio of PDLLA:HA:DBM = 1.5-2:1-1.5:1. The dynamic changes of weight, biomechanical property and pH value of PDLLA/HA/DBM and PDLLA in phosphate buffered saline (PBS, pH 7.4) were studied respectively through degradation tests in vitro.

RESULTSWithout being heated, PDLLA, HA and DBM could be synthesized with the emulsion blend method as bone composite of PDLLA/HA/DBM, which had both osteoconductive and osteoinductive effects. The diameter of the aperture was 100-400 microm and the gap rate was 71.3%. During degradation, the pH value of PDLLA solution decreased lightly within 2 weeks, but decreased obviously at the end of 4 weeks and the value was 4.0. While the pH value of PDLLA/HA/DBM kept quite steady and was 6.4 at the end of 12 weeks. The weight of PDLLA changed little within 4 weeks, then changed obviously and was 50% of its initial weight at the end of 12 weeks. While the weight of PDLLA/HA/DBM changed little within 5 weeks, then changed obviously and was 60% of the initial weight at the end of 12 weeks. The initial biomechanical strength of PDLLA was 1.33 MPa, decreased little within 3 weeks, then changed obviously and kept at 0.11 MPa at the end of 12 weeks. The initial biomechanical strength of PDLLA/HA/DBM was 1.7 MPa, decreased little within 4 weeks, then changed obviously and kept at 0.21 MPa at the end of 12 weeks.

CONCLUSIONSThe emulsion blend method is a new method to prepare bone repair materials. As a new bone repair material, PDLLA/HA/DBM is more suitable for regeneration and cell implantation, and the environment during its degradation is advantageous to the growth of bone cells.

Biocompatible Materials ; Biopolymers ; Bone Density ; physiology ; Bone Matrix ; metabolism ; ultrastructure ; Bone Substitutes ; chemistry ; pharmacology ; Bone and Bones ; drug effects ; physiology ; Durapatite ; chemistry ; pharmacology ; Fracture Healing ; physiology ; Fractures, Bone ; surgery ; In Vitro Techniques ; Lactic Acid ; chemistry ; pharmacology ; Materials Testing ; Osseointegration ; physiology ; Polyesters ; Polymers ; chemistry ; pharmacology ; Sensitivity and Specificity ; Tensile Strength

AIMTo evaluate the testosterone mimetic properties of icariin.

METHODSForty-eight healthy male Sprague-Dawley rats at the age of 15 months were randomly divided into four groups with 12 rats each: the control group (C), the model group (M), the icariin group (ICA) and the testosterone group (T). The reproductive system was damaged by cyclophosphamide (intraperitoneal injection, 20 mg/kg x day) for 5 consecutive days for groups M, ICA and T, at the sixth day, ICA (gastric gavage, 200 mg/kg x day) for the ICA group and sterandryl (subcutaneous injection, 5 mg/rat . day) for the T group for 7 consecutive days, respectively. The levels of serum testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), serum bone Gla-protein (BGP) and tartrate-resistant acid phosphatase activity in serum (StrACP) were determined. The histological changes of the testis and the penis were observed by microscope with hematoxylin-eosin (HE) staining and terminal deoxynucleotidyl transferase biotin-dUTP-X nick end labeling (TUNEL), respectively.

RESULTS(1) Icariin improved the condition of reproductive organs and increased the circulating levels of testosterone. (2) Icariin treatment also improved the steady-state serum BGP and might have promoted bone formation. At the same time, it decreased the serum levels of StrACP and might have reduced the bone resorption. (3) Icarrin suppressed the extent of apoptosis of penile cavernosal smooth muscle cells.

CONCLUSIONIcariin has testosterone mimetic properties and has therapeutic potential in the management of hypoandrogenism.

Animals ; Apoptosis ; drug effects ; Bone and Bones ; drug effects ; metabolism ; Cyclophosphamide ; toxicity ; Drugs, Chinese Herbal ; pharmacology ; Epididymis ; anatomy & histology ; drug effects ; Flavonoids ; pharmacology ; Follicle Stimulating Hormone ; blood ; Luteinizing Hormone ; blood ; Male ; Organ Size ; drug effects ; Rats ; Rats, Sprague-Dawley ; Reproduction ; drug effects ; physiology ; Seminal Vesicles ; anatomy & histology ; drug effects ; Testis ; anatomy & histology ; drug effects ; Testosterone ; blood ; pharmacology

OBJECTIVETo observe the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) in promoting the tendon-bone healing in rabbits after anterior cruciate ligament reconstruction.

METHODSThirty normal adult New Zealand rabbits were divided into 3 groups for anterior cruciate ligament reconstruction using autologous semitendinosus tendons as the graft material. In the rhBMP-2 group, fibrin glue (FG) containing rhBMP-2 was applied to the interface between the tendon graft and the bone tunnel, while in the FG control group, only FG was applied. The blank control group received no treatment after the surgery. The grafts were collected at 2, 4, 8 weeks after the surgery for gross observation and histological examination of the graft incorporation.

RESULTSIn the FG control group, the tendon-bone interface was filled with granulation tissue 2 weeks after the surgery, and the newly generated tissue growing into the bone tunnel and fibroblasts were observed at 4 weeks. Till week 8, Sharpey's fibers were found in the interface with the formation of indirect insertion. In the rhBMP-2 group, the tendon-bone interface was filled with cartilage tissue at 2 weeks, and the four-layer direct insertion was formed at 4 weeks; till week 8, the interface was mainly composed of the direct insertion.

CONCLUSIONrhBMP-2 can induce direct insertion formation in the tendon-bone interface after early anterior cruciate ligament reconstruction. The direct insertion possesses better biomechanical properties than indirect insertion.

Animals ; Anterior Cruciate Ligament ; surgery ; Anterior Cruciate Ligament Injuries ; Bone Morphogenetic Protein 2 ; Bone Morphogenetic Proteins ; therapeutic use ; Bone Regeneration ; drug effects ; Bone and Bones ; physiology ; Humans ; Rabbits ; Recombinant Proteins ; therapeutic use ; Reconstructive Surgical Procedures ; methods ; Tendons ; physiology ; Transforming Growth Factor beta ; therapeutic use ; Wound Healing ; drug effects