Objective To compare the different effects of continuous and intermittent administration of etidronate disodium in bone formation for osteoporosis.Methods Fifty 3 month old virgin female rats weighing (200?10) g were divided equally into 5 groups:pseudo ovariectomized group (group A), ovariectomized group (group B),estrogen replacement group (group C),intermittent etidronate disodium administered group (group D) and continuous etidronate disodium administered group (group E).Postoperative 30 days,group C was given nylostricl 0 1 mg?kg -1 ?d -1 for 100 d;group D was intermittently given etrdonate disodium 10 mg?kg -1 ?d -1 for 14 d and after 35 d interval the drugs were given once more;group E was continuously given etrdonate disodium 10 mg?kg -1 ?d -1 for 100 d.All rats were given drugs orally and were killed at day 100.The bone density,bone mineral content and bone histomorphometrical study were made.Results The average of BMD values of group A,B,C,D,E were [(47 6?2 7),(31 6?7 0),(38 2?4 9),(41 8?8 4),and (29 4?9 4) ( [AKx-]?s ),mg/cm 2] respectively.The value of group E was significant lower than that of group A and group D ( P

Objective To explore possible poisonous and harmful effect of excessive iodine intake on skeleton in male rats. Methods Male rat models receiving various amounts of excessive iodine were established for 3,6, 12 months, and quantitative bone histomorphometric parameters and bone mineral density (BMD) of femur and lumbar spine( L1-1 ) were measured by means of dual-energy X-ray absorptimetry in vitro, and rats receiving normal diet were considered as control group. Results There was no significant difference in bone mineral quantity and structural parameters after feeding excessive iodine for 3 months in comparison with control group. The BMD of L1-4 was significantly increased in all animal groups when various amounts of excessive iodide was taken for 6 months (all P

Objective To study the effect on bone formation by intermittent administration of simvastatin. Methods Seventy three month old virgin female rats, weighted (200?10) g each had been divided into two groups ovariectomized (50 rats) and pseudo ovarectomized (20 rats). Ten rats each of Group A and Group B were sacrified at the 30 th day for the confirmation of successful establishment models of the osteoporosis. Then the remaining animals were re divided into 5 groups: Group A, pseudo ovarectomized control, 10 rats; Group B, ovarectomized control, 10 rats; Group C, given Nylestriol 0.1 mg/(kg?d), 10 rats; Group D, 10 rats, given calcium 10 mg and vitamin D3 2 IU/(kg?d); Group E, 10 rats given simvastatin 5 mg/(kg?d) for 14 days; and the drug was suspended for 28 days, then simvastatin was given for another 14 days. All of the animals were given the agents through gastric tube 30 days after surgery. At 120 th day all the rats were sacrified for the measurements of bone mineral content and bone mineral density by the dual energy X ray absorptiometry for bone mophometrical study. Results The average of bone mineral content was (46?11.34) mg (P

BACKGROUND:Our previous studies have shown that a soft substrate has a significant effect on morphology and cytoskeleton of rat bone marrow mesenchymal stem cel.
OBJECTIVE:To explore the effect of polyacrylamide gels as soft substrates with different elastic moduli on the chondrogenic differentiation of human synovial-derived mesenchymal stem cels.
METHODS:The synovium was harvested from patients with osteoarthritis under sterile conditions, and primary human synovial-derived mesenchymal stem cels were separated using limiting dilution assay. The flow cytometry and multi-directional differentiation experiments were used to identify the cel surface markers and function of the human synovial-derived mesenchymal stem cels, respectively. The polyacrylamide gels with the elastic modulus of 0.4, 6, 30 kPa, which were made using various amounts of acrylamide and bis-acrylamide, were used to culture human synovial-derived mesenchymal stem cels under induction with transforming growth factor-β1 for 7 and 14 days. RT-PCR was used to test the expression of chondrogenic genes, type II colagen gene and cartilage acidic protein 1. The 6-wel cel culture plates served as controls.
RESULTS AND CONCLUSION: The human synovial-derived mesenchymal stem cels showed different cel morphology in the different elastic modulus of polyacrylamide gels. The expression of type II colagen gene and cartilage acidic protein 1 were affected by the different elastic modulus of polyacrylamide gels and culture time, and there was an interaction between these two factors. At 7 days of induction, the expression of cartilage acidic protein 1 gene on 6 kPa polyacrylamide gels was the highest (F=44.350,P=0.000); meanwhile, the expression of type II colagen gene on 0.4 kPa polyacrylamide gels was the highest (F=6.384,P=0.005). These findings indicate that polyacrylamide gels with lower elastic modulus are superior to routine culture plates to promote the chondrogenic differentiation of human synovial-derived mesenchymal stem cels.

Objective To investigate the role of bone metabolic indices in the diagnosis and monitoring of therapeutic effects in osteoporosis, the serum tartrate-resistant acid phosphatase form 5b(TRACP5b) level and other parameters such as Dpd in urine of osteoporosis animal model (ovariotomy rats) in different timing point were measured and analyzed. Methods Eighty female SD rats were divided into five groups and had ovariotomy operation (one group was pseudo-operated). Drug treatment began at the third day after the operation. Six rats in each group were sacrificed after 4 weeks and 14 weeks respectively, the bone metabolic indices were measured and bone histomorphometric data were collected. Results Four weeks after operation, the Dpd/Cr and TRACP5b in ovariotomy group were significantly higher than those in the pseudo-operated group, and TRACP5b was still higher after 14 weeks. In the drug treatment groups, serum E2 level was not changed 4 weeks later, however, Dpd/Cr and TRACP5b had changed greatly. After 14 weeks of drug treatment, there was only a significant decrease of TRACP5b among the bone resorption parameters, but other indices had no change.Bone histomorphometric data showed that the bone volume was improved in each drug treatment group. Conclusions Serum TRACP5b level can reflect the activitiy of osteoclasts and the situation of osteoporosis either in the early stage (high turnover period) or in later stage (low turnover period) of osteoporosis. The drugs used in this experiment can inhibit the ostoclast activity and reduce the level of bone resorption parameters, especially the TRACP5b level. Bone histomorphometric results suggestes that the function and manners of different drugs vary in improving of bone volume.

Objective To study ADFR with statin programmed therapy of osteoporosis in ovariectomized rats.Methods Fifty female rats were randomly allocated into 2 groups:sham operation (S, n =10) and OVX ( n =40) group.After operation for one month,OVX were randomly allocated into 4 groups (each n =10):OVX,statins (T),bisphosphonates (B) and statins+bisphosphonates+calcium+vitamin D (ADFR).After feeding statins or bisphosphonates or ADFR for 100 days,all rats were sacrificed.The effects of T or B or ADFR on bone histomorphology or osteocalcin in sera or deoxypyridoxine in urea were studied.Results The data showed that osteocalcin and deoxypyridine in OVX group were significantly improved compared with S group ( P 0 05) ,in B group was decreased,and in ADFR group was increased compared with OVX group.The histomorphometric date showed that TOS,MOSW,STS/DTS,TBOS,TBSC and iMAR in OVX were significantly increased,and TBV,MLT and ? in OVX were decreased,compared with S group.TBV in B,T and ADFR groups was larger than that in OVX group.TOS,MOSW,TBOS and TBCS in B group were smaller than those in OVX group,? in B group was longer than that in OVX group,TBCS and ? in T group were increased compared with OVX group.Conclusion Statins promote bone turnover,increase osteoblast activity and osteoid production,and reduce the bone construction.Bisphosphonates inhibit bone absorption,while ADFR acelerate bone formation and reduce bone loss,suggesting that polytherapy is preferable to monotherapy.