Bone Gla Protein Research Articles

Beneficial effect of pristimerin against the development of osteoporosis in ovariectomy-induced osteoporosis rats by the RANKL/TRAF6/NF-κB pathway.

Osteoporosis is a major cause of bone fracture in post-menopausal women. We evaluated the effects of pristimerin treatment on ovariectomy-induced osteoporosis, and its possible molecular mechanism. Rats were ovariectomised and biochemical markers of bone formation were determined from serum samples. The microarchitectures of bone tissues were analyzed via micro-CT scans and Western blotting assays. The cytotoxic effects of pristimerin, the differentiation of osteoclasts, and bone reabsorption were evaluated in vitro using RAW 264.7 cells. Treatment with pristimerin attenuated changes in markers of bone formation and reabsorption such as creatine kinase (CK), alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP), collagen type I fragments (CTX), bone Gla-protein (BGP), and osteocalcin (OC) in the serum of ovariectomised rats. It also appeared to restore the microarchitecture of bone tissue. The expression levels of TNF receptor-associated factor 6 (TRAF-6), nuclear factor κ light chain enhancer of activated B cells (NF-κB p65), and receptor activator of nuclear factor-κB ligand (RANKL) protein were significantly lower, while those of Akt and PI3K were significantly higher, in the bone tissues of the pristimerin-treated group than in negative controls. Pristimerin had no cytotoxic effect on RAW 264.7 cells and reduced the differentiation of osteoclasts, bone reabsorption, and translocation of p65 in RANKL-stimulated RAW 264.7 cells in vitro. Pristimerin reduces the effects of osteoporosis by restoring the altered RANKL/TRAF-6/NF-κB pathway in ovariectomised rats.

Lactoferrin ameliorates aging-suppressed osteogenesis via IGF1 signaling.

Lactoferrin (LF) is an iron-binding glycoprotein that plays an important role in promoting bone formation and inhibiting bone resorption; however, its effects on senile osteoporosis remain unknown. This study aimed to investigate the effects and mechanism of LF intervention using a senile osteoporosis model (SAMP6 mice) and senescent osteoblasts. Micro-CT and hematoxylin and eosin staining demonstrated that the intragastric administration (2 g/kg/day) of LF could improve the bone mass and microstructure of SAMP6 mice. Furthermore, LF treatment improved bone metabolism and increased insulin-like growth factor 1 (Igf1) mRNA expression and activated phosphorylation status of AKT. Using osteoblasts passaged for ten generations as an in vitro senescence model, various markers associated with osteoblast formation and differentiation, as well as related indices of oxidative stress were analyzed. Our results revealed that after multiple generations, osteoblasts entered senescence, in conjunction with increased oxidative stress damage, reduced bone metabolism and enhanced expression of aging-related markers. While inhibiting oxidative stress, LF improved osteoblast proliferation by promoting the expression of osteogenesis markers, including alkaline phosphatase (ALP) activity, Igf1, bone gla protein (Bglap) and osteoprotegerin/receptor activator of nuclear factor-kB ligand (Opg/Rankl) mRNA and delayed senescence by decreasing the level of p16 and p21 expression. RNAI-mediated downregulation of IGF1 attenuated the effect of LF on osteogenesis. Therefore, the findings of the present study indicate that LF may promote osteogenesis via IGF1 signaling, thereby preventing senile osteoporosis.

Protective Effect of Acteoside on Ovariectomy-Induced Bone Loss in Mice.

Acteoside, an active phenylethanoid glycoside compound isolated from herbs of Cistanche, was chosen for the investigation of anti-osteoporotic effect on postmenopausal osteoporosis by using an ovariectomized (OVX) mice model. The results from in vivo experiments showed that after daily oral administration of acteoside (20, 40, and 80 mg/kg body weight/day) for 12 weeks, bone mineral density and bone biomechanical properties of OVX mice were greatly enhanced, with significant improvement in bone microarchitecture. Furthermore, biochemical parameters of bone resorption markers as well as bone formation index, including tartrate-resistant acid phosphatase, cathepsin K, deoxypyridinoline, alkaline phosphatase, and bone gla-protein, were ameliorated by acteoside treatment, whereas the body, uterus, and vagina wet weights were seemingly not impacted by acteoside administration. Acteoside significantly affected osteoclastogenesis by attenuating nuclear factor kappa B (NF-κB) and stimulating phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signal pathways through down-regulated levels of tumor-necrosis factor receptor-associated factor 6 (TRAF6), receptor activator of nuclear factor kappa B ligand (RANKL), RANK, NFKBIA, IκB kinase β, nuclear factor of activated T-cells c2 (NFAT2), and up-regulated expressions of PI3K, AKT, and c-Fos. Accordingly, the current research validated our hypothesis that acteoside possesses potent anti-osteoporotic properties and may be a promising agent for the prevention of osteoporosis in the future.

The effect of dissolved carbon dioxide (CO2) on the bone mineral content and on the expression of bone-Gla protein (BGP, Osteocalcin) in the vertebral column of white grouper (Epinephelus aeneus)

The aim of this study was to test the effect of long-term dissolved CO2 exposure on white grouper (Epinephelus aeneus). 45 day post hatching (dph) groupers (0.4 ± 0.05 g; 2.1 ± 0.1 cm) were equally distributed to 15 aquaria (17 L) at a density of 40 larvae per aquarium. The fish were grown for 60 days at a salinity of 25 ppt (26.5 οC) while being exposed to three dissolved CO2 concentrations: Control (0.8 ± 0.1 mg L−1; pH 7.9 ± 0.1), Medium (5.5 ± 0.2 mg L−1; pH 7.1 ± 0.1) and High (28.5 ± 1.5 mg L−1; pH 6.2 ± 0.1). Analysis of bone mineral contents showed that at the end of the CO2 exposure period (105 dph), the Ca levels were significantly higher (P < .001) in the skeleton of fish from the high CO2 treatment as compared to the medium and control treatments. However, the P levels were not significantly different between the three treatments (P > .05). The gene expression of bone Gla protein (BGP, Osteocalcin), a marker for skeletal mineralization, was significantly higher in the vertebral column of the fish from the control treatment as compared to the medium (P < .05) and high (P < .01) treatments. The expression of BGP mRNA was positively correlated with the fish growth rate, as the fish from the control treatment presented the highest body weight at the end of the experiment.

Effects of Zhuang Gu Zhi Tong Formula on Wnt/β-catenin Osteoporosis Pathway Antagonist SOST in Osteoporosis

ObjectiveTo observe the effects of Zhuang Gu Zhi Tong Formula (ZGZTF) on antagonist SOST in canonical Wnt/β-catenin signaling pathway in osteoporosis. MethodsWe analyzed the differential genes of patients with osteoporosis and normal subjects from the GEO database and then found SOST with specific expression. We analyzed SOST as an antagonist of the Wnt signaling pathway by the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Then we studied the effect of ZGZTF on SOST in Wnt signaling pathway. Osteoporosis model was induced by ovariectomy (OVX) in 8-week-old female Sprague–Dawley (SD) rats. After 12 weeks of treatment with ZGZTF by intragastric administration, the rats were put to death in batch. The changes of alkaline phosphatase (ALP), bone gla protein (BGP) and estradiol (E2) in serum were determined, and bone mineral density (BMD) and histomorphology of right femur were observed. Biomechanics of lumbar vertebra were measured, and the expression of SOST, Wnt3a, β-catenin, LRP5, Runx2, Osx and their mRNA involving the canonical Wnt/β-catenin signaling pathway were detected by Western blot, RT-PCR and Immunohistochemical analysis. All data were analyzed by SPSS 22.0. ResultsTwelve weeks of treatment with ZGZTF could significantly decrease the level of ALP and BGP in serum, increase the BMD of femurs, and improve the biomechanical capability of vertebral body in maximum loading and elastic modulus. Concerning histomorphology, we found ordered arrangement of trabeculae, slightly thinning of trabeculae and none obvious slight fractures in femurs after 12 weeks of treatment with ZGZTF. The expression of LRP5, β-catenin, Runx2 and Osx involved in the canonical Wnt/β-catenin signaling pathway was significantly up-regulated in the presence of ZGZTF, and the expression of SOST in this pathway was down-regulated. ConclusionsThese results suggest that ZGZTF may be anti- osteoporosis by down-regulating SOST protein to promote Wnt/β-catenin signaling pathway.

Letrozole induced changes in bone mineral properties and mechanical functions of laying hens

Bone volumes and quality are related to their hormone levels in laying hens. In this study, we investigated letrozole (LZ) induced effects on the physicochemical properties of cortical bone in laying hens. After 9-wk LZ treatment, we observed that LZ could decrease estrogen level in laying hens. As a result, both the plasma tartrate-resistant acid phosphatase and bone Gla protein activities were suppressed significantly. In addition, carbonate substitution was inhibited significantly in humerus and femur confirmed by Raman spectroscopy. Meanwhile, the mineral density and yield load capacities of humerus and femur were improved. This study demonstrated that the high crystallinity and low carbonate substitution were tightly correlated with the relatively enhanced mechanical properties. Moreover, it elucidated biochemical mechanisms of estrogen in regulating mineralogical and mechanical properties of bones in laying hens.

Morphology and genome of a snailfish from the Mariana Trench provide insights into deep-sea adaptation

It is largely unknown how living organisms—especially vertebrates—survive and thrive in the coldness, darkness and high pressures of the hadal zone. Here, we describe the unique morphology and genome of Pseudoliparis swirei—a recently described snailfish species living below a depth of 6,000 m in the Mariana Trench. Unlike closely related shallow sea species, P. swirei has transparent, unpigmented skin and scales, thin and incompletely ossified bones, an inflated stomach and a non-closed skull. Phylogenetic analyses show that P. swirei diverged from a close relative living near the sea surface about 20 million years ago and has abundant genetic diversity. Genomic analyses reveal that: (1) the bone Gla protein (bglap) gene has a frameshift mutation that may cause early termination of cartilage calcification; (2) cell membrane fluidity and transport protein activity in P. swirei may have been enhanced by changes in protein sequences and gene expansion; and (3) the stability of its proteins may have been increased by critical mutations in the trimethylamine N-oxide-synthesizing enzyme and hsp90 chaperone protein. Our results provide insights into the morphological, physiological and molecular evolution of hadal vertebrates.

Humulus lupulus L. Extract Prevents Ovariectomy-Induced Osteoporosis in Mice and Regulates Activities of Osteoblasts and Osteoclasts.

To systematically evaluate the protective effects of Humulus lupulus L. extract (HLE) on osteoporosis mice. In vivo experiment, a total of 35 12-week-old female ICR mice were equally divided into 5 groups: the sham control group (sham); the ovariectomy with vehicle group (OVX); the OVX with estradiol valerate [EV, 0.2 mg/(kg•d)] the OVX with low- or high-dose HLE groups [HLE, 1 g/(kg•d) and 3 g/(kg•d)], 7 in each group. Treatment began 1 week after the ovariectomized surgery and lasted for 12 weeks. Bone mass and trabecular bone mircoarchitecture were evaluated by micro computed tomography, and bone turnover markers in serum were evaluated using enzyme-linked immunosorbent assay (ELISA) kits. In vitro experiment, osteoblasts and osteoclasts were treated with HLE at doses of 0, 4, 20 and 100 µg/mL. Biomarkers for bone formation in osteoblasts and bone resorption in osteoclasts were analyzed. Compared with the OVX group, HLE exerted bone protective effects by the increase of estradiol (P<0.05), the improvement of cancellous bone structure, bone mineral density (P<0.01) and the reduction of serum alkaline phosphatase (ALP), tartrate resistant acid phosphatase (TRAP), bone gla-protein, c-terminal telopeptides of type I collagen (CTX-I) and deoxypyridinoline levels (P<0.01 for all). In vitro experiment, compared with the control group, HLE at 20 µg/mL promoted the cell proliferation (P<0.01), and increased the expression of bone morphogenetic protein-2 and osteopontin levels in osteoblasts (both P<0.05). HLE at 100 µg/mL increased the osteoblastic ALP activities, and HLE at all dose enhanced the extracellular matrix mineralization (both P<0.01). Furthermore, compared with the control group, HLE at 20 µg/mL and 100 µg/mL inhibited osteoclastic TRAP activity (P<0.01), and reduced the expression of matrix metalloproteinase-9 and cathepsin K (both P<0.05). HLE may protect against bone loss, and have potentials in the treatment of osteoporosis.

Osteocalcin (bone GLA protein) levels, vascular calcifications, vertebral fractures and mortality in hemodialysis patients with diabetes mellitus.

Diabetes mellitus is recognized as one of the major causes of end stage kidney disease. Bone Gla protein (BGP) is a vitamin K-dependent protein involved in bone mineralization and vascular calcifications (VC). Our goal was to characterize BGP and undercarboxylated BGP (ucBGP) in DM patients on HD, compared to HD patients without DM, and their association with vascular and bone disease. 387 HD patients from 18 dialysis centers in Italy. Associations of DM, levels of BGP, vitamin D and VC were evaluated. Time-to-event analysis for all-cause mortality was performed by the Kaplan-Meier. Patients with DM had lower levels of total BGP (139.00 vs. 202.50 mcg/L, p < 0.001), 25(OH)D (23.4 vs. 30.2ng/ml, p < 0.001), and ucBGP (9.24 vs. 11.32 mcg/L, p = 0.022). In regression models, the geometric means of total BGP and ucBGP were 19% (p = 0.009) and 26% (p = 0.034) lower in diabetic patients. In univariate Cox regression analysis, DM patients had a higher risk of all-cause mortality (HR:1.83, 95% CI 1.13-2.96, p = 0.014). Adjustment for confounders confirmed the significant DM-mortality link. We included VC and warfarin into the Cox model, the DM-mortality link was no longer significant, suggesting a role of these risk factors as causal mediators leading to increased mortality in dialysis patients. HD patients have an increased mortality risk associated with DM. Furthermore, we found an association between DM and decreased BGP levels. Although our study does not support the notion that BGP levels act as mediator in the DM-mortality link, to our knowledge this is the first study in HD patients suggesting a potential protective role of BGP in the bone, endocrine and vascular pathway.

The organophosphate pesticide -OP- malathion inducing thyroidal disruptions and failures in the metamorphosis of the Senegalese sole, Solea senegalensis

BackgroundOrganophosphate pesticides-OP-, like malathion, can alter the normal functioning of neuro-endocrine systems (e.g., hypothalamus-pituitary-thyroid-HPT- axis), and to interfere on the thyroidal homeostasis. Through direct interactions with thyroid receptors, an/or indirectly via up-stream signalling pathways, from the HPT axis (i.e., negative feedback regulation), malathion possess the ability to affect integrity of thyroidal follicular tissue, and it can also block or delay its hormonal functioning. This insecticide can alter the majority of the ontogenetic processes, inducing several deformities, and also provoking decreases in the growth and survival patterns. The present study has been performed to determine the sublethal effects of malathion during the first month of life of the Senegalese sole, Solea senegalensis, and it is mainly focused on the metamorphosis phase. Different transcript expression levels (i.e. thyroid receptors, matrix and bone -Gla-proteins) and immunohistochemical patterns (i.e. thyroid hormones, osteocalcin, cell proliferation) have been analysed during the most critical phases of the flatfish metamorphosis, that is, through differentiation of thyroid system and skeletal development, migration of the eye, and further adaptation to benthic behaviours.ResultsIn early life stages of the Senegalese sole, the exposure to the highest concentration of malathion (6.25 μg/L) affected to the growth patterns, showing the exposed individuals, a reduction around 60 and 92% of the total length and the dry weigth, respectively. In paralell, a significant reduction of the thyroid follicles (i.e., size and number) it was also been recorded, in a dose-dependent way. Abnormal phenotypes induced in the exposed larvae, did not complete the process of metamorphosis, and displayed several morphological abnormalities and developmental disorders, which were mainly associated with the eye migration process, and with thyroidal and skeletal disorders (i.e., transcriptional and protein changes of thyroid hormones and receptors, and of matrix and bone Gla proteins distribution), that conduced to an inadequate adaptation to the benthic life.ConclusionsIn the Senegalese sole, the majority of the ontogenetic alterations induced by the exposure to malathion were mainly associated to the metamorphosis period, which is a thyroid-driven proccess. In fact, most crucial and transitional ontogenic events, appeared notably disturbed, for e.g., thyroid gland differentiation and functioning, migration of eye, skeletal development and benthonic behaviors.

Relationship between fluoride exposure, orthopedic injuries and bone formation markers in patients with coal-burning fluorosis

Chronic exposure to fluoride is a public health problem worldwide. We explored the relationship between fluoride exposure, orthopedic injuries and bone formation markers alkaline phosphatase (ALP), bone Gla protein (BGP) in participants with coal-burning fluorosis in Hehua Village (coal-burning fluorosis endemic area) in Zhijin County of Guizhou Province and Zhangguan Village (non-fluoride contaminated area) in Anshun City of Guizhou Province. Environmental samples were collected and fluoride contents were examined using a fluoride ion-selective electrode. Dental fluorosis and skeletal fluorosis of 295 participants from Hehua Village and 85 participants from Zhangguan Village were diagnosed with informed consent. Urinary samples and peripheral blood samples were collected from the participants to determine urinary fluoride (UF), ALP acti-vity, and BGP content. The results showed that fluoride contents in rice, pepper, corn, drinking water, clay, vegetable-grown soil, coal and indoor and outdoor air were significantly higher than those in the control area, but lower than the previously reported values. With the increases of UF concentration, the ALP activity and BGP content significantly increased, the severity of skeletal fluorosis was greater, but with no significant changes in dental fluorosis. There was positive correlation between the severity of skeletal fluorosis and ALP activity, BGP content. These results indicated that low fluoride exposure could cause orthopedic injuries. ALP and BGP could be used to eva-luate the bone turnover in patients with skeletal fluorosis, which would be useful in the auxiliary diagnosis and therapeutic evaluation of skeletal fluorosis.

Tai chi for treating osteopenia and primary osteoporosis: a meta-analysis and trial sequential analysis

PurposeThe aim of this meta-analysis was to evaluate the efficacy of Tai chi (TC) as an adjuvant treatment for osteopenia and primary osteoporosis.MethodsWe went through eight databases to identify relevant randomized controlled trials that compared TC with a control group. The primary outcome was osteoporosis-related fractures (fracture incidence). Meta-analyses and trial sequential analyses (TSA) were conducted using RevMan 5.3 and TSA 0.9.ResultsFifteen randomized controlled trials involving a total of 857 patients were included in the analyses. No trials reported primary outcome; however, bone mineral density (BMD) values differed significantly in subgroup 1 (TC vs no treatment; weighted mean difference [WMD] =0.05 g/cm2, 95% CI 0.03 to 0.07; P<0.00001; P for heterogeneity =0.22, I2=22%) and subgroup 2 (TC vs conventional treatments; WMD =0.16 g/cm2, 95% CI 0.11 to 0.21; P<0.00001; P for heterogeneity =0.008, I2=75%). In addition, two trials compared TC with conventional treatments, which found a significant difference in bone gla protein (standardized mean difference =−1.18, 95% CI −1.66 to −0.70; P<0.00001; P for heterogeneity =0.58, I2=75%). The results of the BMD were confirmed by TSA. Also, TC may have a certain effect on the relief of osteoporotic pain (WMD = −2.61, 95% CI −3.51 to −1.71; WMD = −1.39, 95% CI −2.01 to −0.77). However, it did not promote the quality of life, level of serum calcium, serum phosphorus, and also had no effect on bone turnover markers.ConclusionAlthough there is no study monitoring fracture incidence, TC may be beneficial for patients in improving BMD values, level of bone gla protein, and relieving osteoporotic pain. However, due to the low methodological quality, current evidence for treating osteopenia and primary osteoporosis through TC is insufficient.

Effects of Percutaneous Kyphoplasty on Bone Metabolism and Oxidative Stress in Elderly Patients with Osteoporotic Spinal Fractures.

To investigate the effects of percutaneous kyphoplasty on bone metabolism and oxidative stress in elderly patients with osteoporotic spinal fractures. An experimental study. Department of Orthopedics, ZhangYe People's Hospital Affiliated to HeXi University, from February 2016 to October 2017. A total of 100 elderly patients with osteoporotic spinal fractures were randomly divided into the observation group treated with percutaneous kyphoplasty (PKP) and the control group treated with percutaneous vertebroplasty (PVP), with 50 cases in each group. One month after surgery, the content of serum bone metabolic markers bone gla protein (BGP), carboxyl-terminal collagen I crosslinks (- &beta;), bone alkaline phosphatase (BALP) and tartrate-resistant acid phosphatase (TRACP), oxidative stress markers malondialdehyde (MDA), total antioxidant capacity (TAC) and superoxide dismutase (SOD) were compared between the two groups. Visual analogue scale (VAS) and the Oswestry Disability Index (ODI) were used to evaluate the degree of pain and functional status of the two groups, and the Cobb angles were measured in both groups. One month after surgery, the level of the serum bone metabolic marker BGP in the observation group was higher than the control group (p<0.001), and the levels of -CTX, BALP and TRACP in the observation group were lower than the control group (all p<0.001). The level of the serum oxidative stress marker MDA in the observation group was lower than the control group (p<0.001), and the levels of TAC and SOD in the observation group were higher than the control group (all p<0.001). There were no significant differences in VAS scores and ODI values between the two groups (p=0.806 and 0.913, respectively). Cobb's angle of the injured vertebrae in the observation group was smaller than the control group (p<0.001). Compared with PVP, PKP is more effective in treating elderly patients with osteoporotic spinal fractures. It can effectively optimise bone metabolism, promote fracture healing, and reduce the oxidative stress reactions after surgery, with a relatively larger application value.

Lycium barbarum polysaccharides promoted proliferation and differentiation in osteoblasts.

Osteoblasts have the capacity to differentiate into several different cell types, including adipocyte, chondrocyte, and muscle lineages. Therefore, osteoblast can be potentially applied in the treatment of bone diseases. The factors controlling osteoblast differentiation is complex. Recently, it has been reported that some natural products regulate the differentiation in osteoblasts and promote bone formation. Based on these findings, this study demonstrated that Lycium barbarum polysaccharides (LBP) could promote proliferation of osteoblast MC3T3-E1 cells through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Besides, expression of key proteins correlated with cellular proliferation such as proliferating cell nuclear antigen (PCNA) and Ki67 was enhanced in the presence of LBP. We also detected the increased expression of bone-specific matrix proteins such as morphogenetic protein 2 (BMP2), bone Gla protein (BGP), osteopontin (OPN), and α-1 type-I collagen (COL1A1) when treated with LBP. This process was mediated by some signals, such as smad1, smad8, Runt-related transcription factor 2 (RUNX2), and Osterix. Furthermore, RUNX2 silencing inhibited osteoblast differentiation by decreasing expression of bone-specific matrix proteins. Collectively, we proposed a previously unidentified function of LBP in osteoblast differentiation, suggesting its potential clinical role in bone disease treatment.

Green tea (Camellia sinensis) aqueous extract alleviates postmenopausal osteoporosis in ovariectomized rats and prevents RANKL-induced osteoclastogenesis in vitro.

BackgroundGreen tea (Camelliasinensis [L.] Kuntze) belongs to the plant family Theaceae and is mainly distributed in East Asia, the Indian subcontinent and Southeast Asia. This plant has been proven to be beneficial to human health, and green tea is the second most consumed beverage in the world after water. However, until now, the effect of green tea aqueous extract (GTE) upon postmenopausal osteoporosis has remained unclear. In this study, we investigated the therapeutic effects of GTE on estrogen deficiency-induced osteoporosis and explored the possible mechanisms in vivo and in vitro.Materials and methodsOvariectomized (OVX) female rats were orally administered with GTE at doses of 60, 120, and 370 mg kg−1 for 13 consecutive weeks. The biochemical parameters, bone gla protein, alkaline phosphatase, acid phosphatase, estrogen, interleukin-1β, and interleukin-6 in blood samples were detected, and histological change in bones was analyzed by hematoxylin and eosin staining. Meanwhile, the mechanisms of GTE on osteoclast formation were explored in RAW 264.7 cells induced by receptor activation of the nuclear factor kappa B ligand (RANKL).ResultsThe results showed that GTE could increase bone mass and inhibit trabecular bone loss in OVX rats. Furthermore, real-time quantitative reverse transcription polymerase chain reaction analysis from in vitro experiments also showed that GTE reduced the mRNA expression of osteoclast-associated genes such as cathepsin K (cath-K), c-Fos, matrix metalloproteinase 9, nuclear factor of activated T cells cytoplasmic 1 (NFATc1) and tartrate-resistant acid phosphatase. In addition, GTE caused a reduction in the protein levels of NFATc1, c-Fos, c-src and cath-K.ConclusionEvidence from both animal models and in vitro experiments suggested that GTE might effectively ameliorate the symptoms of osteoporosis in OVX rats and inhibit RANKL-induced osteoclast-specific gene and protein expression.

Irp2 Knockout Causes Osteoporosis by Inhibition of Bone Remodeling.

It has been found that iron disorder may lead to osteoporosis. However, the mechanism has been little explored. In the present study, we try to investigate the effects of iron disorder on bone metabolism using Irp2 knockout (Irp2-/-) mice. Female Irp2-/- mice were used in this study. Bone mineral density (BMD) was measured by Micro-CT. Serum markers for bone turnover were measured by enzyme-linked immunosorbent assay. Content of iron was measured in bone and liver tissue, and Vitamin D 25-hydroxylase (CYP2R1) content was measured in liver tissue. Relative gene expression involved in iron export and uptake, and some genes involved in activities of osteoblast and osteoclast were all measured by real-time PCR and western blot. Compared to wild-type mice, Irp2-/- mice exhibited reduced BMD, bone iron deficiency, and hepatic iron overload. Serum levels of 25(OH)D3 and markers for bone formation such as bone alkaline phosphatase (Balp), bone-gla-protein (BGP), and type I collagen alpha1 chain (Col I α1) were decreased, while markers for bone resorption including cathepsin K (Ctsk) and tartrate-resistant acid phosphatase (Trap) were all significantly increased. Hepatic CYP2R1 level was decreased in Irp2-/- mice compared with wild-type control mice. Compared to wild-type C57BL6 control mice, the expression of genes involved in osteoblast activity such as Balp, BGP, and Col I α1 were all significantly decreased in bone tissue, while genes for osteoclast activity such as Ctsk and Trap were all markedly increased in Irp2-/- mice at mRNA level. Genes involved in iron storage, uptake, and exporting were also measured in bone tissue. Posttranscriptionally decreased ferritin (FTL), ferroportin 1 (FPN1), and increased transferrin receptor 1 (TfR1) gene expressions have been unexpectedly found in bone tissue of Irp2-/- mice. Irp2-/- mice exhibit reduced bone iron content and osteoporosis. Decreased circulating 25(OH)D3 levels promoted activity of osteoclast, while impaired activity of osteoblast may contribute to pathogenesis of osteoporosis. And, reduced bone iron content may not be totally caused by TfR1-dependent pathways.

Clinical observastion of Bushen-Qiangjin capsule and calcium D on aromatase inhibitors- induced osteopenia in breast cancer patients

Objective To observe the clinical effect of the Bushen-Qiangjin capsule and calcium D in the treatment of aromatase inhibitors-associated bone loss (AIBL) in breast cancer patients. Methods A total of 65 patients were randomized into a treatment group and a control group, 32 in the control group taking calcium D, and 33 in the treatment group taking calcium D and Bushen-Qiangjin capsule. After a 3-month treatment, the bone mineral density T (BMD), bone-specific alkaline phosphatase (BALP), bone gla protein (BGP) and tartrate resistant acid phosphatase (TrACP) of two groups were evaluated. Results The BMD increased significantly after treatment in both groups (P<0.05), and the therapeutic efficacy of the treatment group was better than of the control group (P<0.05). After treatment, the level of BALP (308.76 ± 10.99 U/L vs. 280.00 ± 7.44 U/L, t=8.170) and the BGP (42.21 ± 3.04 ng/ml vs. 34.38 ± 2.06 ng/ml, t=6.818) of the treatment group were significantly higher than those of the control group (P<0.01). The level of TrACP decreased significantly after treatment in both groups (P<0.05), and the TrACP (60.12 ± 4.58 U/L vs. 67.25±4.06 U/L, t=1.653) of treatment group was significantly lower than that of the control group (P<0.05). Conclusions The Bushen-Qiangjin capsule can produce a content efficacy in treating AIBL in breast cancer patients, improving the BMD and bone metabolism. Key words: Breast neoplasms; Bushen-Qiangjin capsule; Aromatase inhibitors; Bone density; Osteocalcin; Tartrate-resistant acid phosphatase

Correlation analysis between interleukin 6 polymorphism and adolescent idiopathic scoliosis susceptibility and bracing effectiveness

To analyze the correlation between the polymorphism on interleukin 6 (IL-6) gene promoter region-174 locus and adolescent idiopathic scoliosis (AIS), including the susceptibility, the bracing effectiveness, and the possible mechanism. The 182 AIS patients and 210 healthy controls who met the inclusion criteria between January 2013 and January 2016 were collected as research objects. The genotype of IL-6 gene promoter region-174 locus, the serum IL-6, the bone mineral density (BMD) of femoral neck and vertebrae (L 1-4), and the bone metabolism parameters, including bone alkaline phosphatase (BALP), bone gla protein (BGP), tartrate resistant acid phosphatase 5b (TRACP-5b), urine Ca, and urine Ca/Cr, were detected. All research objects were divided into the AIS group and the control group according to whether they had AIS, the GG, CG, CC groups according to their genotype, and progression-free group and progression group according to the therapeutic effectiveness of 1-year bracing treatment. Statistical analysis for the indexes were conducted respectively. There were significant differences in AIS history, BMD of femoral neck and lumbar vertebrae between the AIS group and control group ( P<0.05). According to the therapeutic effecitveness of 1-year bracing treatment, 182 AIS patients were divided into progression-free group in 110 cases and progression group in 72 cases. The results of single factor analysis showed that there were significant differences in the genotype and allele distribution of IL-6 gene promoter region-174 locus, BMD of femoral neck and lumbar vertebrae, IL-6, TRACP-5b, urine Ca, and urine Ca/Cr between the progression-free group and progression group ( P<0.05). The results of multivariable analysis showed that the BMD of lumbar vertebrae, TRACP-5b, and urine Ca were the influencing factors of bracing efficacy ( P<0.05). According to the results of genotype detection, all research objects were divided into GG group in 264 cases, CG group in 104 cases, and CC group in 24 cases. The IL-6, TRACP-5b, urine Ca, and urine Ca/Cr of GG type carriers were higher and BMD of femoral neck and lumbar vertebrae were lower when compared with the CG and CC type carriers ( P<0.05). The BMD of lumbar vertebrae of CG type carriers was lower than that of CC type carriers ( P<0.05). The polymorphism of IL-6 genepromoter region-174 locus wasn't correlated with the AIS susceptibility, but it was correlated (not independently correlated) with the scoliosis progression under bracing treatment, and the risk for G-carried patients was higher. The mechanism may be that the polymorphism affected the IL-6 expression level and eventually affected the BMD of AIS patients through the bone metabolism.

Icariin prevents bone loss by inhibiting bone resorption and stabilizing bone biological apatite in a hindlimb suspension rodent model.

Bone loss induced by microgravity is a substantial barrier to humans in long-term spaceflight. Recent studies have revealed that icariin (ICA) can attenuate osteoporosis in postmenopausal women and ovariectomized rats. However, whether ICA can protect against microgravity-induced bone loss remains unknown. In this study, the effects of ICA on a hindlimb suspension rodent model were investigated. Two-month-old female Wistar rats were hindlimb suspended and treated with ICA (25 mg·kg-1·d-1, i.g.) or a vehicle for 4 weeks (n = 6). The bone mass density of the hindlimbs was analyzed using dual-energy X-ray absorptiometry and micro-CT. mRNA expression of osteogenic genes in the tibia and the content of bone metabolism markers in serum were measured using qRT-PCR and ELISA, respectively. The bone mineral phase was analyzed using X-ray diffraction and atomic spectrometry. The results showed that ICA treatment significantly rescued the hindlimb suspension-induced reduction in bone mineral density, trabecular number and thickness, as well as the increases in trabecular separation and the structure model index. In addition, ICA treatment recovered the decreased bone-related gene expression, including alkaline phosphatase (ALP), bone glaprotein (BGP), and osteoprotegerin/receptor activator of the NF-κB ligand ratio (OPG/RANKL), in the tibia and the decreased bone resorption marker TRACP-5b levels in serum caused by simulated microgravity. Notably, ICA treatment restored the instability of bone biological apatite and the metabolic disorder of bone mineral elicited by simulated microgravity. These results demonstrate that ICA treatment plays osteoprotective roles in bone loss induced by simulated microgravity by inhibiting bone resorption and stabilizing bone biological apatite.

Effects of platelet-rich plasma on angiogenesis and osteogenesis-associated factors in rabbits with avascular necrosis of the femoral head.

Platelet-rich plasma (PRP) contains various growth factors and cytokines that can enhance the recovery of the damaged tissues. The present study aimed to examine the effects of PRP on the recovery of avascular necrosis of the femoral head (ANFH), and to provide novel insights into the clinical treatment of this disease. A total of 24 New Zealand white rabbits were randomly divided into the normal control group, ANFH model and PRP-treated groups (n =1 2 each). Blood samples were extracted from the auricular vein at 4, 8 and 12 weeks after establishing the model to determine the hemorheological indexes, as well as the content of serum osteocalcin bone Gla-protein (BGP) and vascular endothelial growth factor (VEGF). In addition, femoral head tissue was collected, with part of it used for hematoxylin and eosin (HE) staining to observe the histological changes. The remaining was used to detect the mRNA expression levels of alkaline phosphatase (AKP), basic fibroblast growth factor (bFGF), transforming growth factor-β1 (TGF-β1), bone morphogenetic protein 2 (BMP-2) and platelet-derived growth factor B (PDGF-B) by reverse transcription-polymerase chain reaction. Compared with the model group, PRP treatment significantly improved the hemorheological indexes, as well as significantly increased the contents of BGP and VEGF. In the PRP group, the expression levels of TGF-β1, bFGF, BMP-2 and PDGF-B were significantly upregulated, while AKP expression was downregulated compared with the model group. Furthermore, PRP evidently improved the histological structure of the ANFH tissue. PRP was able to improve the hemorheological indexes following femoral neck fracture, repair the local blood vessels, and promote the expression of osteoblast-associated and angiogenesis-associated factors, which suggested a high efficiency in repairing ANFH.