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Transgenic zebrafish are a common vertebrate model system for the study of addictive behavior. In the present study, plasmid constructs containing green fluorescent protein (GFP) and the promoter of tyrosine hydroxylase (TH), a key synthetic enzyme for catecholamines, were produced. The TH-GFP constructs were microinjected into zebrafish embryonic cells. Three days post-fertilization, GFP began expressing in distinct catecholaminergic areas. The TH-GFP transgenic zebrafish were employed as live biosensors to test the effects of the commonly abused drugs nicotine and ketamine. First, locomotion assays were used to study the general excitatory effects of the drugs. Maximal locomotor activity was obtained after treatment with a high concentration of nicotine (10 μM), but with a much lower concentration of ketamine (0.1 μM). Second, TH protein levels in zebrafish brains were assessed by Western blot. TH protein levels were significantly increased, with maximal protein levels found after treatment with the same drug concentrations that gave maximal locomotor activity. Importantly, analysis of GFP in the zebrafish catecholaminergic areas revealed the same expression patterns as was obtained by Western blot. The present results indicate that increased locomotor activity can be correlated to TH protein expression, as indicated by Western blot and expression of TH-GFP. We have shown that TH-GFP expression is a reliable method to show the effects of drugs on TH expression that may be employed as a novel high-throughput live biosensor for screening drugs of abuse.

This study investigated a phytoestrogen-rich herb formula, Xianlinggubao (XLGB) (including genistein 510 microg/g and daidzein 2500 microg/g), concerning prevention of OVX-induced deterioration of musculoskeletal tissues in 11-month-old female Wistar rats, which were randomized into Sham, OVX, and XLGB groups. Daily oral administration of XLGB (250 mg/kg/day) started after OVX for 3 months. mRNA of MHC-I IIa IIb of abductor muscle was determined by RT-PCR. The proximal femoral BMD and geometry, microarchitecture, and mechanical strength were evaluated by pQCT, micro-CT, and compressive testing, respectively. The bone turnover biochemical markers serum osteocalcin (OC) and urinary deoxypyridinoline (DPD) were evaluated. The results showed that (1) XLGB-treated OVX rats showed no difference compared to the Sham group, whereas OVX induced significant deterioration in variables related to bone density, microarchitecture, and mechanical strength (P0.05); (2) biochemical markers showed no difference between sham and XLGB groups as compared with higher bone turnover in OVX rats (P0.05); (3) mRNA expression of MHC-I IIa IIb was downregulated in OVX rats but upregulated after XLGB treatment (P0.05); and (4) as compared with the OVX group, no uterine hypertrophy was found in XLGB-treated rats. In conclusion, findings of this study suggested that the herbal preparation XLGB was able to prevent OVX-induced deterioration of musculoskeletal tissues at the hip without causing uterine stimulation.

Cytochrome P450 (CYPs) is significant in degradation of endogenous substrates and detoxification of carcinogens, therefore it is a biomarker for assessment of polycyclic aromatic hydrocarbons (PAHs) level in aquatic environment. In the present study, a transgenic line of zebrafish had been generated using a CYP-green fluorescence protein (CYP-GFP) construct, driven by CYP1A1 promoter. Polychlorinated biphenyls (PCBs) were used as toxicant, in concentrations of 0.02 μg/ml, 0.04 μg/ml, 0.08 μg/ml, 0.4 μg/ml, and 0.8 μg/ml. The transgenic control fish showed low intensity of fluorescence in the liver. After exposed to PCBs, zebrafish had morphological changes such as expansion of yolk, contortion of tails and inflation of pericardial area. Green fluorescence signals were found to express according to concentrations and time. The green fluorescence signal was most intense after treatment with 0.08 μg/ml PCBs. However, the maximum area of green fluorescent signal was found at 0.04 μg/ml PCBs. GFP started to express at 3h exposure to PCBs, increasing its intensity until 6 h exposure, and then level off. Since the GFP expression is fast responding and is sensitive to low PAHs concentrations, transgenic fish is a good tool for live imaging and monitoring of aquatic contamination.

Melatonin deficiency has been postulated as an etiologic factors in adolescent idiopathic scoliosis (AIS). In previous studies, melatonin was shown to regulate skeletal growth and bone formation in both humans and rats. Although it remains controversial whether there are differences in serum melatonin level between AIS and control subjects, melatonin signaling pathway dysfunction in osteoblasts has been reported in patients with AIS. Recently, our group found that melatonin receptor 1B (MT2) gene polymorphism was associated with the occurrence of AIS. Hence, the present study investigated the effect of melatonin on AIS osteoblasts. In vitro assays were performed with osteoblasts isolated from 17 severe AIS girls and nine control subjects. The osteoblasts were exposed to different concentrations of melatonin for 3 days. The effects of melatonin on cell proliferation (as evidenced by MTT assay) and differentiation (demonstrated by alkaline phosphatase activity) were determined. In the control group, melatonin significantly stimulated osteoblasts to proliferate and differentiate. However, in the AIS group, the stimulatory effects of melatonin were not discernible. Importantly, this finding demonstrated that there is a significant difference between AIS and control osteoblasts in functional response toward melatonin. Melatonin-stimulated proliferation of control osteoblasts was inhibited by the MT2 antagonist, 4-phenyl-2-propionamidotetraline, as well as by luzindole, a nonselective melatonin receptor antagonist, suggesting that MT2 is associated with the proliferative action of melatonin. The lack of response in AIS osteoblasts might be because of dysfunction of the melatonin signaling pathway, which may contribute to the low bone mineral density and abnormal skeletal growth observed in patients with AIS.

This study was designed to investigate bone properties using heel quantitative ultrasound (QUS) in young adults participating in various sports.A cross sectional study was performed on Chinese male students (n = 55), aged 18-22 years. Subjects with previous fractures or suffering from any diseases known to affect bone metabolism or taking any medication with such an effect, were not included. The subjects were categorised according to their main sporting activities, including soccer (n = 15) (a high impact, weight bearing exercise), dancing (n = 10) (a low impact, weight bearing exercise), and swimming (n = 15) (non-weight bearing exercise). A sedentary group acted as controls (n = 15). A reproducibility study of the velocity of sound (VOS) and the broadband ultrasound attenuation (BUA) measurement was performed and analysed using the intraclass correlation coefficient (ICC).There was good intra-investigator and inter-investigator agreement (ICCor = 0.8; p0.05) in the measurement of BUA and VOS. No significant differences in BUA and VOS (p0.05) were found between the dominant and non-dominant heel. Soccer players (137 +/- 4.3 dB/MHz; 1575 +/- 56 m/s; 544.1 +/- 48.4) and dancers (134.6 +/- 3.7 dB/MHz; 1538 +/- 46 m/s; 503.0 +/- 37.0) had significantly higher BUA, VOS, and stiffness index (SI) scores (p0.05), respectively, than swimmers (124.1 +/- 5.1 dB/MHz; 1495 +/- 42 m/s; 423.3 +/- 46.9) and the sedentary control group (119.9 +/- 6.1 dB/MHz; 1452 +/- 41 m/s; 369.9 +/- 46.4). A trend of a significant linear increase with the weight bearing and high impact exercise was revealed in all QUS parameters (p0.05).This cross sectional study indicated that regular participation in weight bearing exercise in young people might be beneficial for accruing peak bone mass and optimising bone structure.

Aim: Factorial design was used to test our hypothesis whether a group of flavonoids (FE) derived from herbal Epimedium Brevicornum Maxim exerted its preventive effects on estrogen-deficiency-induced osteoporosis mainly through an enhancement in intestinal calcium absorption. Materials and methods: Forty-five 12-month-old female Wistar rats were used and randomly assigned into sham-operated group and four ovariectomy (OVX) subgroups, i.e. OVX with vehicle (OVX group), OVX with FE (FE group), OVX with calcium supplement (CS group), and OVX with FE and CS (FE + CS group). Daily oral administration of FE (10 mg/kg/day) and/or CS (56 mg/kg/day) started on day 4 after OVX for 12 weeks. Before sacrificing the animals, urine and serum samples were collected for assaying indicators related to intestinal calcium absorption, regulator for calcium homeostasis, and markers of bone turnover. The left proximal femur was dissected for evaluation of the primary end-point (failure force), the second end-points (pQCT-quantified densitometry, geometry, and micro-CT-quantified 3-D trabecula micro-architecture), and pQCT-defined cross-sectional envelope. Results: FE was found to be able to prevent OVX-induced reduction in failure force as well as the above second end-points, without resulting in an increased uterus weight. CS had no preventive effect on OVX-induced reduction in failure force. Two-way factorial interaction analysis between FE and CS showed that the un-enhanced suppression of parathyroid hormone for calcium homeostasis did not provide link between the enhanced intestinal calcium absorption and the enhanced inhibition of bone resorption in the present study. Furthermore, the discrepancies between the enhanced intestinal calcium absorption and the un-enhanced end-point measures as well as anabolic effect were also revealed by the interaction analysis. Conclusion: The present study suggested that FE inhibited bone resorption, stimulated bone formation, and accordingly prevented osteoporosis without hyperplastic effect on uterus in the OVX rat model, which was however independent of an enhancement in intestinal calcium absorption.

This study was performed to evaluate the potential benefits of regular Tai Chi Chun (TCC) exercise on bone mineral density (BMD) and neuromuscular function in postmenopausal women. In this cross-sectional study, 99 healthy postmenopausal women, with a mean age of 55.9+/-3.1 years and within 10 years after the menopause, were recruited; including 48 subjects who had been regularly practicing TCC exercise for more than 3 h/week and 51 age- and sex-matched sedentary controls (CON). BMD was measured in the lumbar spine and proximal femur of the non-dominant leg (femoral neck, greater trochanter, and Ward's triangle), using dual-energy X-ray absorptiometry (DXA). Neuromuscular function was evaluated, including magnitude of trunk bend-and-reach, quadriceps muscle strength, and single-stance time on the nondominant leg. The TCC group showed overall higher BMD at all measurement sites, with a significant difference found at the spine (7.1%), greater trochanter (7.2%), and Ward's triangle (7.1%) of the proximal femur (all; P