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Plastin 3 (PLS3), a protein involved in formation of filamentous actin (F-actin) bundles, is important in human bone health. Recent studies identify PLS3 as a novel bone regulator and PLS3 mutations can lead to a rare monogenic early-onset osteoporosis. However, the mechanism of PLS3 mutation leading to osteoporosis is unknown, and its effective treatment strategies have not been established. Here, we have constructed a novel rat model with clinically relevant hemizygous E10-16del mutation in PLS3 ( PLS3 E10-16del/0 ) that recapitulates the osteoporotic phenotypes with obviously thinner cortical thickness, significant decreases in yield load, maximum load, and breaking load of femora at 3, 6, 9 months old compared to wild-type rats. Histomorphometric analysis indicates a significantly lower mineral apposition rate in PLS3 E10-16del/0 rats. Treatment with alendronate (1.0 µg/kg/day) or teriparatide (40 µg/kg five times weekly) for 8 weeks significantly improves bone mass and bone microarchitecture, and bone strength is significantly increased after teriparatide treatment (p＜0.05). Thus, our results indicate that PLS3 plays an important role in the regulation of bone microstructure and bone strength, and we provide a novel animal model for the study of X-linked early-onset osteoporosis. Alendronate and teriparatide treatment could be a potential treatment for early-onset osteoporosis induced by PLS3 mutation., Competing Interests: JH, BZ, XL, QZ, FG, LS, JL, OW, YJ, WX, XX, ML No competing interests declared, (© 2023, Hu et al.)

Introduction: Osteoporosis leads to more serious consequences in men than in women, but less is known about its impacts on health-related quality of life (HRQoL) of men, and whether the anti-osteoporosis treatment can improve HRQoL of men with osteopenia/osteoprosis., Methods: We enrolled men with primary osteoporosis and age-matched healthy controls. We collected medical history, serum levels of carboxyl-terminal type I collagen telopeptide, procollagen type I propeptides, and bone mineral density of patients. All patients and controls completed the short-form 36 (SF-36) questionnaires. Changes in HRQoL of osteopenia/osteoporosis men were prospectively evaluated after alendronate or zoledronic acid treatment., Results: A total of 100 men with primary osteoporosis or osteopenia and 100 healthy men were included. The patients were divided into three subgroups: osteopenia (n = 35), osteoporosis (n = 39) and severe osteoporosis (n = 26). Men with osteoporosis or severe osteoporosis had impaired HRQoL in domains of physical health compared to healthy controls. HRQoL scores in physical health related domains of patients with severe osteoporosis were significantly lower compared to healthy controls, and were the poorest among the three subgroups of patients. Fragility fracture history was correlated with lower SF-36 scores about physical health. In 34 men with newly diagnosed osteoporosis receiving bisphosphonates treatment, HRQoL scores were significantly improved in domains of physical health after treatments., Conclusions: The HRQoL is significantly impaired in men with osteoporosis, and the more severe the osteoporosis, the poorer the HRQoL. Fragility fracture is an important influencing factor of deteriorated HRQoL. Bisphosphonates treatment is beneficial to improve HRQoL of osteopenia/osteoporosis men., (© 2023. The Author(s).)

Zoledronic acid (ZOL) is a therapy inhibiting bone resorption. In this study, generic ZOL (Yigu®) showed its clinical efficacy consistency with original ZOL (Aclasta®) in Chinese postmenopausal women with osteoporosis. This study provides a practical basis for the application of Yigu® in Chinese population., Introduction: Yigu® has been approved its bioequivalence to Aclasta®. However, the clinical efficacy and safety of Yigu® have not been evaluated yet. Here, we compared the effectiveness and safety between Yigu® and Aclasta® in Chinese postmenopausal women with osteoporosis and assessed the efficacy of intravenous infusion of ZOL., Methods: This was a randomized open-label, active-controlled study in postmenopausal women with osteoporosis of 14 clinical centers in China. Postmenopausal women with osteoporosis were recruited and randomized to receive a single infusion of 5 mg Yigu® or Aclasta®. The primary endpoint was the percentage change in bone mineral density (BMD) at lumbar spine after 12 months of treatment and was assessed for equivalence. The secondary endpoint was the percentage change in BMD at proximal femur after 12 months. Additional secondary endpoints were percentage changes in BMD at the above sites after 6 months of treatment and changes in bone turnover biomarkers during ZOL treatment. Safety was also evaluated and compared between two groups., Results: A total of 458 postmenopausal women with osteoporosis were enrolled (n = 227, Yigu®; n = 231, Aclasta®). The mean percentage change in the BMD had no statistical difference at the lumbar spine (5.32% vs 5.18%), total hip (2.72% vs 2.83%), and femoral neck (2.37% vs 2.81%) between Yigu® and Aclasta® groups after 12 months of treatment. The mean difference of BMD change at the lumbar spine after 12 months between two groups was 0.15% (95% CI: - 0.71 to 1.00, equivalence margin: - 1.5%, 1.5%), demonstrating the treatments were equivalent. Meanwhile, the decreases in the P1NP and β-CTX showed no difference between two groups after 14 days and 6 and 12 months of treatment. As regards the whole sample, BMD significantly increased after 12 months of treatment. Also, serum C-terminal telopeptide of type 1 collagen (β-CTX) and procollagen 1 N-terminal peptide (P1NP) significantly decreased at each visit period. The overall adverse events were comparable and quite well between two groups., Conclusion: Intravenous infusion of zoledronic acid achieved the potent anti-resorptive effects which led to significant increase in BMD of Chinese postmenopausal women with osteoporosis. Yigu® was equivalent to Aclasta® with respect to efficacy and safety., (© 2021. The Author(s).)

Objective: Duchenne muscular dystrophy (DMD) is a severe X-linked progressive neuromuscular disease that brings a significantly increased risk of osteoporosis and bone fractures. We prospectively evaluated the effects of oral and intravenous bisphosphonates on the bones of children with DMD., Methods: This study included a total of 52 children with DMD. They were divided into zoledronic acid (ZOL), alendronate (ALN), and control groups according to bone mineral density (BMD) and history of fragility fractures. For 2 years, all patients took calcium, vitamin D, and calcitriol. Meanwhile, 17 patients received infusions of ZOL, and 18 patients received ALN. BMD, serum levels of alkaline phosphatase (ALP) and the cross-linked C-telopeptide of type I collagen (β-CTX) were evaluated., Results: After 24 months of treatment, the percentage changes in lumbar spine BMD were 23.2 ± 9.7% and 23.6 ± 8.8% in the ZOL and ALN groups (all P<.01 vs. baseline). The increases did not differ between the ZOL and ALN groups, but were significantly larger than those of the control group (P<.01). Serum β-CTX and ALP levels, respectively, were decreased by 44.4 ± 18.0% and 31.9 ± 26.7% in the ZOL group and by 36.0 ± 20.3% and 25.8 ± 14.4% in the ALN group (all P<.01 vs. baseline)., Conclusion: Zoledronic acid and alendronate had similar protective effects to increase bone mineral density and reduce bone resorption in children with DMD, which were superior to treatment of calcium, vitamin D, and calcitriol., Abbreviations: 25OHD = 25 hydroxyvitamin D; ALN = alendro-nate; ALP = alkaline phosphatase; ALT = alanine aminotransferase; BMD = bone mineral density; BP = bisphosphonate; Ca = calcium; β-CTX = cross-linked C-telopeptide of type I collagen; DMD = Duchenne muscular dystrophy; FN = femoral neck; GC = glucocorticoid; LS = lumbar spine; ZOL = zoledronic acid., (© 2020 American Association of Clinical Endocrinologists. Published by Elsevier, Inc. All rights reserved.)

Pregnancy- and lactation-associated osteoporosis (PLO) is a rare disorder with poorly known etiology, pathophysiology, and therapy. We aimed to investigate the clinical characteristics of PLO and evaluate the effectiveness and safety of bisphosphonates on it. A total of 12 patients were diagnosed with PLO on the basis of medical history, bone mineral density (BMD), and/or fragility fractures during pregnancy and lactation. We investigated the clinical, biochemical, and radiological characteristics of patients. We assessed the effects of alendronate or zoledronic acid through observing the changes of bone turnover biomarkers and BMD during the treatment. Secondary osteoporosis was excluded by comprehensive differential diagnosis. The mean age of these patients was 31 ± 5 years old. All of these patients presented severe back pain. Multiple vertebral compression fractures (VCFs) were found in 10 patients, and the median (P25th, P75th) number of compressed vertebra was 3 (3, 5). Ten patients had vitamin D insufficiency or deficiency. Serum level of bone resorption marker (β-CTX with mean of 0.68 ± 0.41 ng/ml) was moderately higher than the normal range. BMD at lumbar spine, femoral neck, and total hip were low as 0.894 ± 0.153 g/cm 2 , 0.728 ± 0.090 g/cm 2 , and 0.728 ± 0.080 g/cm 2 , respectively. Either alendronate or zoledronic acid could effectively relieve bone pain, reduce β-CTX level, and increase BMD. PLO is a rare type of osteoporosis, which was characterized by increased bone resorption and decreased BMD, even VCFs. Bisphosphonate therapy was well tolerated and effective in management of PLO, but needed to be further verified in randomized controlled trial.

Background: Zoledronic acid (ZOL) is widely used for treatment of glucocorticoid-induced osteoporosis. The most common adverse effects of ZOL treatment are post-dose symptoms. ZOL-induced hepatotoxicity has very rarely been reported., Case Report: Here, we described a 50-year-old Chinese woman who had vertebral fractures and severe back pain after glucocorticoid therapy for Behcet disease for 13 years. Three days after ZOL 5 mg infusion in April 2012, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (GGT) levels increased by 7.7, 4.9 and 3.0 times, respectively, compared with pre-treatment values. Liver protective agents were administered per os. Her hepatic enzyme levels returned to nearly normal range 9 days post-infusion. In the subsequent ZOL infusion with 1 year interval, serum ALT, AST and GGT levels increased slightly after the second infusion and were sustained to be normal after the third infusion. Her post-dose symptoms alleviated in the meantime., Conclusions: Hepatotoxicity due to ZOL therapy is a rare, but possible adverse effect which may be relieved after subsequent infusions.

Aim: To investigate the association between SOST gene polymorphisms and response to alendronate treatment., Materials & Methods: 639 Chinese postmenopausal women with osteoporosis or osteopenia received alendronate treatment. Polymorphisms of SOST were analyzed. Bone mineral density (BMD), serum ALP and β-CTX levels were measured. The correlation of SOST polymorphisms with changes of BMD and bone biomarkers after treatment was analyzed., Results: rs1234612 and rs851054 polymorphisms were correlated to baseline lumbar spine BMD (p < 0.05). After 12 months of treatment rs1234612 and rs865429 polymorphisms were correlated to BMD changes at the lumbar spine (p < 0.05) or femoral neck (p < 0.05), respectively., Conclusion: The polymorphisms of SOST are genetic factors affecting bone health and response to alendronate in Chinese postmenopausal women.

Aim: To investigate the association between LRP5 gene polymorphisms and response to alendronate in Chinese osteoporotic women., Materials & Methods: Six hundred and thirty nine Chinese postmenopausal women with osteopenia or osteoporosis were included and received alendronate treatment. The A1330V polymorphism of LRP5 was investigated. Bone mineral density (BMD) and bone turnover markers (ALP and β-isomerized carboxy-telopeptide of type I collagen [β-CTX]) were measured before and after treatment. The correlation of LRP5 polymorphisms with changes in BMD and bone turnover biomarkers were analyzed after treatment., Results: After 12 months of treatment, participants with CC and CT genotypes had a larger increase in lumbar spine BMD and a larger decrease in serum β-CTX and ALP levels than those with TT genotype (all p < 0.001). No significant genotype-treatment interaction was found in hip BMD., Conclusion: The A1330V polymorphism of LRP5 is possibly correlated with response to alendronate treatment in Chinese women with osteoporosis, and the TT genotype could possibly predict a weak response to alendronate.

Objective: To analyze the clinical features of pregnancy and lactation-associated osteoporosis (PLO)., Methods: The clinical data of 4 patients with PLO were retrospectively analyzed., Results: Bone pain and limitation of motion appeared within 2 months after childbirth in these 4 patients. X-ray films showed multiple vertebral fractures of thoracic and/or lumbar spine. Three of the 4 patients had positive family history of osteoporosis or low trauma fractures. After the diagnosis of PLO was confirmed, lactation was discontinued, and treatment of calcium, active vitamin D analogues, and bisphosphonates were initiated. After these managements, no new fracture occurred and the BMD at L(2-4) was markedly increased by 12.7% - 22.7% during their follow-up period of 1 - 4 years., Conclusion: Women with positive family history of osteoporosis or low trauma fractures may be susceptible to PLO. PLO should be considered when lumbar or back pain occur during pregnancy and lactation. Besides calcium and active vitamin D analogues, anti-resorptive agents (bisphosphonate or calcitonin) may be effective on PLO.

Aim: To observe the efficacy and safety of Rocaltrol (calcitriol) and/or Caltrate D (calicum carbonate plus vitamin D) in elderly Chinese women with osteopenia or osteoporosis., Methods: One hundred fifty Chinese women aged over 65 years with osteopenia or osteoporosis from three centers were randomly divided into two groups. Seventy-six participants received Caltrate D as one pill daily; the other 74 participants received 0.25 mug Caltrate D plus Rocaltrol daily. The changes in bone mineral density (BMD) served as primary end-points. Height changes, the presence of new vertebral fractures, muscle strength and balance were evaluated., Results: The following are the mean percentage changes (and SD) in BMD over 12 months: at L2-L4, 0.83+/-3.88 in the Caltrate D group and 2.84+/-4.04 in the Rocaltrol+Caltrate D group (P=0.003, by ANCOVA); at the femoral neck, 0.04+/-3.94 in the Caltrate D group and 2.01+/-5.45 in the Rocaltrol+Caltrate D group (P=0.085, by ANCOVA); and in the trochanter, 1.59+/-4.57 in the Caltrate D group and 3.76+/-6.25 in the Rocaltrol+Caltrate D group (P=0.053, by ANCOVA). The stand and maximal forward reach test (SMFRT) was significantly enhanced in both groups during the 12 months of treatment, but no significant differences were found between these two groups. No severe adverse event related to these medications occurred throughout the study., Conclusion: Treatment with Rocaltrol plus Caltrate D or Caltrate D for 12 months in elderly Chinese postmenopausal women effectively increased BMD at the lumbar spine. Rocaltrol plus Caltrate D was more effective at the lumbar spine than Caltrate D alone.

Objective: To investigate the influence of age on bone mass in Cushing's syndrome patients., Methods: Measurement of bone mineral density (BMD) was conducted among 57 women with Cushing's syndrome (CS) and 49 healthy women. There were 14 CS women and 14 healthy women in the group aged 20 - 29; 27 CS women and 15 healthy women in the group aged 30 - 39; and 16 CS women and 20 healthy women in the group aged 40 - 49., Results: Among the healthy women the peak bone mass of lumbar spine was in the group aged 30 - 39, while the peak bone mass of hip was in the group aged 20 - 29. The BMD values of the CS women were lower than those of the healthy women, especially those in lumbar spine and in Ward's triangle. The younger the CS women, the lower the BMD Z-score (for the BMD Z-score of lumbar spine P = 0.021, for the BMD Z-score of femoral neck P = 0.020, and for the BMD Z-score of Ward's triangle P = 0.026). Seventeen of the 57 (29.8%) CS women had osteoporosis, 29 (50.9%) of the 57 had osteopenia, and 15 (26.3%) had fractures. The CS women with bone fractures had lower BMD Z-score than those without fractures (for lumbar fracture P = 0.003)., Conclusion: The BMD of CS women is lower than that of the healthy women. Bone loss is more severe in younger CS women than in older ones. CS women with low BMD are prone to have bone fracture.

Objective: To implore the effects of teriparatide (PTH) and alendronate (Alen) on skeletal biomechanical properties of ovariectomized (OVX) osteoporotic rats., Methods: 70 female Wistar rats of 6 months were randomly divided into 7 groups: (1) Baseline: sacrificed at baseline; (2) OVXb: sacrificed in 6 weeks after OVX; (3) Sham operation; (4) OVXe: sacrificed 14 weeks after OVX; (5) PTH: 40 microg.kg(-1).d(-1); (6) Alen: 100 microg.kg(-1).d(-1); (7) A + P: PTH 40 microg.kg(-1).d(-1) and Alen 100 microg.kg(-1).d(-1). In group (5)-(7), different medicines were injected 5 times per week from 6th to 14th week after OVX. The cancellous biomechanical properties were measured with indentation test and the cortical properties were investigated with three-point bending test., Results: (1) The can load and can stiff of distal femur of OVXb were significantly lower than those of baseline (P < 0.01). It is indicated that osteoporotic rat models with impaired bone strength were established. (2) The can load and can stiff of distal femur of PTH [(36.3 +/- 9.2) N, (160.7 +/- 48.0) N/mm(2)], Alen [(42.7 +/- 13.0) N, (122.9 +/- 35.6) N/mm(2)] and A + P [(44.3 +/- 18.2) N, (105.2 +/- 58.4) N/mm(2)] groups were all higher than those of OVXe [(19.5 +/- 8.5) N, (83.2 +/- 37.7) N/mm(2), P < 0.001 or P < 0.01]. In femoral shaft, maximal load and elastic load in PTH, Alen and A + P groups were higher than those of OVXe (P < 0.001, P < 0.01 or P < 0.05). (3) Can stiff in distal femur was higher in PTH than that in Alen and A + P groups (P < 0.05). Elastic load, maximal load and energy absorption in femoral shaft were higher in PTH and A + P groups than those in Alen group (P < 0.05), and maximal stress was higher in PTH than that in A + P and Alen group (P < 0.05)., Conclusion: PTH and Alen were effective in improving the skeletal mechanical properties of OVX rats, but improvement in Alen and A + P was not so good as that in PTH group. It is indicated that anabolic effects of PTH was retarded by Alen's significant inhibition of bone turnover, therefore, PTH and Alen should not be utilized simultaneously.

Objective: To investigate the effects of teriparatide (hPTH1-34, PTH) and alendronate (Alen) on bone turnover rate and bone mineral density (BMD) of ovariectomized (OVX) osteoporotic rats., Methods: 70 female 6-month-old Wistar rats were randomly divided into 7 groups: (1) baseline group: killed immediately as baseline controls; (2) sham operation group: injected subcutaneously with normal saline (NS) as normal controls; (3) OVXb group: underwent ovarietomy (OVX) and killed 6 weeks after OVX as pre-therapeutic controls; (4) OVXe group: injected with NS subcutaneously and then sacrificed 14 weeks after OVX as controls by the end of treatment; (5) PTH group: PTH 40 microg.kg(-1).d(-1) was administered; (6) Alen group: Alen 100 microg.kg(-1).d(-1) was administered; (7) A + P group: PTH 40 microg.kg(-1).d(-1) and Alen 100microg.kg(-1).d(-1) were administered. In groups 4 approximately 7, different medicines were injected subcutaneously QD 5 times per week from the 6th week to the 14th week after OVX and then the rats were killed and their right femurs, lumbar vertebrae, and samples of blood and urine were collected. Absorptometry was used to measure the BMD of the right femur and lumbar vertebrae. The serum calcium, phosphate, creatinine, alanine transaminase, and alkaline phosphatase (ALP) activity were measured by automatic biochemical analysis. The bone resorption marker urine deoxypyridinoline/creatinine (UDpd/Cr) level was measured by enzyme-linked immuosorbent assay., Results: Six weeks after OVX the ALP and UDpd/Cr levels in the OVXb group were 101 U/L +/- 59 U/L and (118 +/- 32) x 10(-6) respectively, both significantly higher than those of the baseline group (58 U/L +/- 10 U/L and (48 +/- 34) x 10(-6) respectively, both P < 0.01) and the BMD results of the OVXb group were all significantly lower than those in the baseline group (all P < 0.01), which indicated that an OVX osteoporotic rat model was established successfully. The ALP and UDpd/Cr levels of the Alen group were 61 U/L +/- 28 U/L and (17 +/- 39) x 10(-6), significantly lower than those of the PTH group 120 U/L +/- 36 U/L and (111 +/- 26) x 10(-6) respectively, both P < 0.01) and the UDpd/Cr levels of the A + P group were between those of the Alen group and those of the PTH group. The BMD levels of the femur and lumbar vertebrae of the PTH, Alen, and A + P groups were all significantly higher than those of the control groups (all P < 0.01), and were similar to or higher than those of the sham operation group without significant differences between the PTH and Alen groups. The BMD level of the lumber vertebrae of the A + P group were significantly higher than those in the PTH group (all P < 0.05), and the femoral BMD results of the A + P group were significantly higher than those in the PTH and Alen groups (all P < 0.01)., Conclusion: PTH and Alen are all effective on osteoporosis. In particular, the combination of PTH and Alen is more effective on increasing the BMD level.

Objective: To observe the changes of urinary deoxypyridinoline crosslink/creatinine (UDpd/Cr) in rats after OVX and intervention by estrogen and bisphosphonate and investigate the possible application of deoxypyridinoline in osteoporosis diagnosis and treatment., Methods: 40 female 6-month-old virginal Wistar rats were divided into 5 groups, ovariectomized or sham ovariectomized. (1) Ovxb (n = 8): sacrificed at 6 weeks after OVX; (2) Sham (n = 8): sham ovariectomized; (3) Ovxe (n = 8): sacrificed at 14 weeks after OVX; (4) O + E (n = 9):OVX + 17 beta estradiol [20 micrograms/(kg.d) ih]; (5) O + C (n = 7):OVX + cimadronate [0.2 mg/(kg.d)]; Treatment started 6 weeks after OVX and lasted 8 weeks. Rats in group 2-5 were sacrificed at 14 weeks after OVX. Urinary and serum biochemical parameters were measured, pQCT scanning of femur, bone biomechanical test in femur were determined., Results: OVX resulted in increasing of UDpd/Cr 133.3% (P < 0.01). The ratio of UCa/Cr also increased in OVX groups but without any significant compared with Sham (P > 0.05). UDpd/Cr were reduced by 54.6% and 51.8% (P < 0.01) in O + E, O + C group respectively compared with Ovxe. The significant negative correlationships were found between UDpd/Cr and bone mass, BMD and biomechanic characteristics., Conclusions: UDpd/Cr ratio is a sensitive bone resorption marker, a marked changes were observed when the rats ovariectomized or treated with estradiol and cimadronate. There were best correlation between UDpd/Cr and bone mineral density and bone biomechanic characteristics. It is fair to apply UDpd/Cr ratio for osteoporosis diagnosis and treatment.

Objectives: To evaluate the value of peripheral quantitative computed tomography (pQCT) in measuring bone architecture and biomechanic properties., Methods: 50 virgin female Wistar rats six months old were randomly divided into 4 groups: (1) 8 rats were killed as baseline group; (2) 8 rats underwent sham operation and then were killed 14 weeks after (sham operation group); (3) 16 rats underwent bilateral ovariectomy (OVX) without further intervention. Six and 14 weeks after the operation each 8 rats were killed (OVX group); and (4) 18 rats underwent OVX too. After the OVX 9 of the 18 rats were treated with 17beta-estradiol 20 micro g/kg/d IH and 9 rats were treated with estradiol valerate 800 micro g/kg/d po for 8 weeks respectively. Then the 18 rats were killed (OVX plus estrogen group, O + E group). The right tibiae of the rats were taken for histomorphometric analysis, and the right femora were prepared for pQCT scanning and bone biomechanical measurement with indentation test and three-point bending test., Results: Histomorphometric analysis showed that the trabecular volume of proximal tibia (Cn-BV/TV) in the OVX group was 8.1 +/- 1.4%, significantly lower than that in the sham operation group (19.5 +/- 1.5%, P < 0.01). pQCT scanning showed that the femoral trabecular bone mineral content (Trab BMC) in the OVX group was 1.7 +/- 0.3 mg/mm, significantly lower than that in the sham operation group (3.2 +/- 0.5 mg/mm, P < 0.01) and the femoral trabecular bone mineral density (Trab BMD) in the OVX group was 158 +/- 32 mg/mm(3), significantly lower than that in the sham operation group (320 +/- 39 mg/mm(3), P < 0.01). The cancellous maximal load (Can load) of the distal shaft of femur in the OVX group was 12.5 +/- 2.5 N, significantly lower than that in the sham operation group (45.9 +/- 3.2 N, P < 0.01). The cancellous stiffness (Can Stiff) of the distal shaft of femur in the OVX group was 226 +/- 48 N/mm, significantly lower than that in the sham operation group (396 +/- 72 N/mm, P < 0.01). The Can load of O + E group was 21.8 +/- 3.7 N, significantly higher than that in the OVX group (P < 0.05). The Can Stiff of the O + E group was 382 +/- 54 N/mm, significantly higher than that in the OVX group (P < 0.05). There were no significant differences in cortical bone determined by pQCT as well as biomechanic properties in measured by three point test after OVX and estrogen treatment. A significant positive correlation was shown between Trab BMD and Cn-TV/BV and between Trab BMD and Tb N (r = 0.88 and 0.73, both P < 0.01). Similarly, both Trab BMC and Trab BMD of the femur were significantly correlated with the Can load and Can Stiff determined by indentation test (r = 0.47 - 0.68, all P < 0.01). There was also a significant correlation of parameters measured by pQCT in cortical bone with the maximal load and stiffness for the femur midshaft, and the best correlation was found between the maximal load of femur midshaft and Crt BMC and Crt A (both r = 0.76 and P < 0.01)., Conclusion: The geometric, densitometric and mechanical properties in cortical and trabecular bones of rat can be well described by pQCT.

Aim:Oral risedronate is effective in the treatment of postmenopausal osteoporosis when administered daily, weekly, or monthly. In this 1-year, randomized, double-blind, multicenter study we compared the weekly 35-mg and daily 5-mg risedronate dosing regimens in the treatment of Chinese postmenopausal women with osteoporosis or osteopenia.Methods:Postmenopausal women with primary osteoporosis or osteopenia were randomly assigned to the weekly group or daily group (n=145 for each) that received oral risedronate 35 mg once a week or 5 mg daily, respectively, for 1 year. The subjects' bone mineral densities (BMDs), bone turnover markers (P1NP and β-CTX), new vertebral fractures, and adverse events were assessed at baseline and during the treatments.Results:All subjects in the weekly group and 144 subjects in the daily group completed the study. The primary efficacy endpoint after 1 year, ie the mean percent changes in the lumbar spine BMD (95% CI) were 4.87% (3.92% to 5.81%) for the weekly group and 4.35% (3.31% to 5.39%) for the daily group. The incidences of clinical adverse events were 48.3% in the weekly group and 54.2% in the daily group.Conclusion:The weekly 35-mg and daily 5-mg risedronate dosing regimens during 1 year of follow-up show similar efficacy in improving BMDs and biochemical markers of bone turnover in Chinese postmenopausal women with osteoporosis or osteopenia. Moreover, the two dosing regimens exhibit similar safety and tolerability. [ABSTRACT FROM AUTHOR]

The efficacy and safety of intravenous ibandronate were evaluated in postmenopausal osteoporosis women in China. In this multicenter, positive drug-controlled study, 158 postmenopausal osteoporotic women were randomized to receive 2 mg ibandronate given intravenously once every 3 months or 70 mg alendronate given orally once per week. All women also received supplemental calcium (500 mg) and vitamin D (200 IU) daily. One hundred fifty-one patients completed the 1-year study. Ibandronate produced mean increases in bone mineral density (BMD) by 4.27% at the lumbar spine, 3.48% at the femoral neck, and 2.03% at the trochanter. Mean increases in BMD by 4.24% at the lumbar spine, 2.72% at the femoral neck, and 2.99% at the trochanter were observed in the alendronate group. No significant difference was found between the two groups in BMD in all sites measured. Significant decreases in serum c-telopeptide of type I collagen (CTX) and alkaline phosphatase (ALP) were found in the two groups after 1 and 3 months of treatment, respectively; these serum CTX and ALP levels were then maintained at the decreased levels throughout the study period (12 months). No changes of stature were found in the patients of the two groups. Adverse events were similar in the two groups, except more mild muscle pain was observed in the first month after infusion of ibandronate than with oral alendronate (P < 0.001). The results observed in Chinese patients may support the observation that intravenous ibandronate significantly reduced bone resorption and increased BMD with good tolerance in Chinese postmenopausal osteoporotic women. Use of intravenous ibandronate possibly could potentially improve compliance as compared with other oral bisphosphonates because it may avoid the peptic side effects of oral bisphosphonate. [ABSTRACT FROM AUTHOR]

Osteoporosis is a disease of disequilibrium between bone formation and bone loss, and vitamin D is one of the key hormones in the regulation of bone metabolism, the major role of which is to provide the proper micro-environment for bone mineralization. Vitamin D deficiency which has been defined by most experts as circulating 25-hydroxyvitamin D levels of less than 20 ng/mL (50 nmol/L) is widespread all over the world. As shown by the results of recent studies, vitamin D deficiency could increase the risk of low bone mineral density or osteoporosis, muscle disorders, falls, and as a matter of course, fractures due to both osteoporosis and falls. Long-term supplementation of vitamin D and calcium are good prevention measures for osteoporosis, falls and fractures. At the same time, they are essential components of osteoporosis management. Many studies show that sufficient vitamin D intake could increase bone mass, and decrease the risk of falls and fractures. [ABSTRACT FROM AUTHOR]

Objective To investigate the relationship between geranylgeranyl pyrophosphate synthase ( GGPPS ) gene polymorphisms and bone response to alendronate in Chinese osteoporotic women. Methods A total of 639 postmenopausal women with osteoporosis or osteopenia were included and randomly received treatment of low dose (70 mg per two weeks) or standard dose (70 mg weekly) of alendronate for one year. The six tag single nucleotide polymorphisms of GGPPS gene were identified. Bone mineral density (BMD), serum cross-linked C-telopeptide of type I collagen (β-CTX), and total alkaline phosphatase (ALP) were measured before and after treatment. GGPPS gene polymorphisms and the changes of BMD and bone turnover markers after treatment were analyzed. Results rs10925503 polymorphism of GGPPS gene was correlated to serum β-CTX levels at baseline, and patients with TT genotype had significantly higher serum β-CTX level than those with TC or CC genotype (all P<0.05). No correlation was found between polymorphisms of GGPPS gene and serum total ALP levels, as well as BMD at baseline. After 12 months of treatment, lumbar spine and hip BMD increased and serum bone turnover markers decreased significantly (P<0.01), and without obvious differences between the low dose and standard dose groups (all P >0.05). However, GGPPS gene polymorphisms were uncorrelated to percentage changes of BMD, serum total ALP, and β-CTX levels (all P>0.05). Conclusion GGPPS gene polymorphisms are correlated to osteoclasts activity, but all tag single nucleotide polymorphisms of GGPPS gene have no influence on the skeletal response to alendronate treatment. [ABSTRACT FROM AUTHOR]