Rutaecarpine exerted anti-osteroporosis / 药学学报

Osteoprotegerin (OPG), secreted by osteoblasts, is a marker of bone turnover. OPG can inhibit osteoclastic differentiation by binding receptor activator of nuclear factor-κB ligand (RANKL). In this study, we found that rutaecarpine (RUT) had the up-regulating OPG activity, and it could significantly increase OPG protein levels in both mouse embryonic osteogenic precursor MC3T3-E1 and human osteosarcoma U-2OS cells. Osteoblastogenic differentiation calcified nodules staining results showed that RUT significantly promoted the osteogenic differentiation of MC3T3-E1 cells. Osteoclastic differentiation tartrate resistant acid phosphatase (TRAP) staining results showed that RUT obviously inhibited the osteoclast differentiation of mouse macrophages RAW264.7 induced by RANKL. In vivo studies showed that low-dose RUT group (5 mg·kg-1·day-1) and high-dose RUT group (45 mg·kg-1·day-1) treatments for 3 months significantly increased bone density in ovariectomized (OVX) rats; calcein double labeling experiment and toluidine blue staining results indicated that low-dose RUT group promoted bone formation and decreased bone loss in vivo; immunohistochemistry results showed that low-dose RUT group increased the expression of OPG in rat femur. All animal procedures were performed in accordance with the regulations of the Institutional Animal Care and Use Committee of Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences. In summary, this study demonstrated that RUT could up-regulate OPG expression and had promoting osteoblastic differentiation and inhibiting osteoclastic differentiation effects in vitro and in vivo.

Low-dose zoledronic acid regulates osteoclasts and osteoblasts in the extraction socket of ovariectomized rats / 中国组织工程研究

BACKGROUND: Although zoledronic acid can effectively prevent bone loss in postmenopausal women, its effect and mechanism on the mandible are not clarified. OBJECTIVE: To study the morphological and pathological changes of mandibular tissue in ovariectomized rats treated with low-dose zoledronic acid and to investigate the regulatory effect and mechanism of RANKL/RANK/OPG signaling system in the inhibition of bone resorption by zoledronic acid. METHODS: Thirty-six adult female Sprague-Dawley rats were randomized into control, model and treatment groups. Animal models of osteoporosis were made by bilateral ovariectomy in the latter two groups, while the same amount of lipid tissues surrounding the ovary was removed in the control group. Three weeks after ovariectomy, the rats in the treatment group were given subcutaneous injection of 20 µg/kg zoledronic acid. The corresponding doses of saline were injected subcutaneously in the control and model groups. One week after treatment, the left mandibular molars were extracted from all the rats, and the rats’ jaws were separated and removed at 4 weeks after tooth extraction for detection. The residual alveolar bone of the extracted socket was observed by X-ray. The pathological changes of the mandibular cortex and cancellous bone were detected by hematoxylin-eosin staining. The number of apoptotic osteoblasts was detected by TUNEL apoptosis test. The expressions of receptor activator of nuclear factor-κ B ligand (RANKL), osteoprotegerin and nuclear transcription factor-κB (NF-κB) in the mandibular alveolar bone were detected by immunohistochemical technique. Western blot was finally used to detect the expression of RANKL and NF-κB at protein levels. RESULTS AND CONCLUSION: (1) At 4 week after tooth extract, subcutaneous injection of 20 µg/kg zoledronic acid effectively inhibited alveolar bone resorption and promoted new bone formation at the extraction socket. (2) Hematoxylin-eosin staining results showed that: in the model group, the cortical bone was thinned, and the trabecular bone was thinned and even ruptured. There were a large number of bone resorption lacunae but few osteoblasts in the model group. In the treatment group, the cortical bone was thickened and the trabecular bone had normal structure, with only a small amount of bone resorption lacunae and increased number of osteoblasts. (3) The number of apoptotic osteoblasts was significantly lower in the treatment group than the model group (P < 0.001). (4) Immunohistochemical staining results showed significantly decreased RANKL and NF-κB protein expressions (P < 0.001, P < 0.002) and significantly increased osteoprotegerin level (P < 0.001) in the treatment group than the model group. (5) Western blot results revealed that the protein expressions of RANKL and NF-κB in the model group were significantly higher than those in the control group, and treatment with zoledronic acid significantly reduced these protein levels (both P < 0.001). To conclude, zoledronic acid could inhibit the differentiation of osteoclasts by down-regulating the NF-κB signal pathway and meanwhile regulate the apoptosis of osteoblasts.

Effects of Different Interventions on Biomechanic Indexes of Femur Bones of Ovariectomized Rats with Osteoporosis / 中国运动医学杂志

Objective To investigate the effects of different interventions on the biomechanic indexes in femur bones of ovariectomized rats with osteoporosis.Methods Eighty healthy female Sprague-Dawley rats,aged 3 months,were randomly divided into an ovariectornized(OVX,n=68)group and a sham-operation(Sham,n=12)group.At the 11th week after the operation,the OVX group was further randomly divided into a control group(n=11),an estradiol group(E2,n=10),a genisteine group(G,n=10),a treadmill exercise group(TE,n=10),a lithium chloride group(LiCl,n=10)and a whole-body vertical vibration group (WBVV,n=10).Then the rats began to receive different interventions as their group names implied.At the end of 8 weeks,their right femurs were isolated and the biomechanic parameters were detected using the three point bending test.Results (1)Both the maximum load and elastic load in E2,G,TE,WBVV and LiC1 groups were significantly higher than that of the control group,while no significant differences were seen in maximum deflection and elastic deflection.(2)The elastic stress,maximum strain,and elasticity modulus in E2,G,and WBVV groups were significantly higher than that of the control group,while no significant differences were seen in maximum stress and elastic strain among them.The maximum stress,elastic stress,maximum strain,and elasticity modulus in TE group were significantly higher than the control group while no significant differences were seen in the elastic strain.The maximum stress,elastic stress,and elasticity modulus in LiC1 group were significantly higher than the control group,but no significant differences were seen in maximum strain and elastic strain between them.Conclusion E2,genistein,treadmill exercise,whole-body vertical vibration,and LiC1 have quite similar effects on structural mechanics indexes of femurs in OVX rats with osteoporosis,but they have different impacts on the material mechanics indexes.

Expression of Glu、mGluR 5 and EAAT 1 in bone tissues of ovariectomized osteoporotic rats and the effects of Total Flavonoids of Rhizoma Drynariae on it / 中国生化药物杂志

Objective To observe the expression of Glu、mGluR 5 and EAAT 1 in bone tissues of ovariectomized osteoporotic rats and the effects of Total Flavonoids of Rhizoma Drynariae (TFRD) on it. Methods 45 SPF 3-month-old Sprague-Dawley (SD) female rats were randomly divided into sham operation (Sham, n=15) group and ovariectomized (OVX, n=30) group. The osteoporotic(OP) model was established by bilateral ovariectomy, 14 weeks later, we measured bone mineral density(BMD) by dual-energy X-ray and determined that OP model was successfully replicated, OVX group rats were then divided into OVX group (n=15) and OVX+TFRD group (n=15). The OVX+TFRD group was given TFRD for 12 weeks. Glutamate (Glu), metabotropic glutamate receptor 5 (mGluR 5), and Glutamate/Aspartate Transporter (GLAST/EAAT 1)’s expression of femur was examined in order to clarify the characteristics of bone glutamate signaling pathway and the effects of TFRD on it. Results Glu and ionotropic receptors mGluR 5 mainly distributed in bone marrow cells and osteoblasts closed to the bone marrow cavity walls. There were no significant differences in Glu expression among Sham group, OVX group and OVX+TFRD group. The mGluR 5 expression of OVX+TFRD group was significantly higher than that of Sham group and OVX group(P=0.009), while no significant difference was found between the latter two groups. In addition to large distribution in bone marrow cells, small amount of transporter EAAT 1 was noted to express in bone cells of the bone lacunae. There were no significant differences in EAAT 1 expression among the three groups. Conclusion In bone glutamate signaling pathway, this study demonstrated that TFRD could significantly improve the ionotropic receptor mGluR 5’s expression, but had no inlfuence for Glu and EAAT 1.

Correlation between bone mineral density and serum vascular endothelial growth factor levels in ovariectomized rats / 中国组织工程研究

BACKGROUND: Vascular endothelial growth factor play an important role in promoting healing of osteoporotic fractures, but whether it can affect the bone mineral density is not clear. OBJECTIVE: To observe the correlation between serum vascular endothelial growth factor, bone mineral density and the number of osteoblasts in the ovariectomized rats. METHODS: Forty female Sprague-Dawley rats were randomly divided into ovariectomized group and control group. After 3 months, the bone mineral density of the whole body, femur and lumbar spine was measured. Rat enzyme-linked immunosorbent assay kit was used to measure the level of serum vascular endothelial growth factor. Then, the rats in two groups received femoral metaphyseal fixation, decalcified, dehydrated, embeding in paraffin, slicing and hematoxylin-eosin staining. Each slice was free to take five fields of view (10×40) in order to count the osteoblasts of femur distal metaphysis under optical microscope. RESULTS AND CONCLUSION: After ovariectomized for 3 months, the rats body mass was increased significantly (P 0.05), and the difference of the osteoblast number between ovariectomized group and control group was not significant (P > 0.05). This indicated that there was no correlation between bone mineral density and the number of osteoblasts and vascular endothelial growth factor level in the ovariectomized group and the control group. These findings suggest that the bone mineral density is reduced and the body mass is increased in the ovariectomized rats, and the reduced bone mineral density of ovariectomized rats may be irrelevant with the change of serum vascular endothelial growth factor.

Effect of Trifolium pratense isoflavones on osteoporosis rats induced by estrogen deficiency / 中国药学杂志

OBJECTIVE: To examine the effects of Trifolium pratense isoflavones (TPIF), the main active component of Trifolium pratense L., on ovariectomy-induced osteoporosis in rats. METHODS: A total of 60 six-month-old female rats were randomly assigned to a sham-operated group and five ovariectomized(OVX) groups, ie, OVX with vehicle(10 mL · kg-1 · d-1, ig), OVX with graded doses of TPIF(30, 60, and 90 mg · kg-1 · d-1, ig), and OVX with nilestriol(2.5 mg · kg-1 · week-1, ig). The animals were sacrificed after 12-week treatment. RESULTS: Compared to the OVX group, TPIF significantly inhibited the increase of body weight. In addition, TPIF administration significantly decreased serum levels of alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP), and increased serum level of estrogen. CONCLUSION: TPIF may be a potential alternative medicine for the prevention and treatment of postmenopausal osteoporosis. Its mechanism may be related to increasing estrogen level, inhibiting bone resorption, and promoting bone formation.

Effect of Dietary Calcium on Spinal Bone Fusion in an Ovariectomized Rat Model

OBJECTIVE: To evaluate the effect of calcium supplementation on spinal bone fusion in ovariectomized (OVX) rats. METHODS: Sixteen female Sprague Dawley rats underwent bilateral ovariectomy at 12 weeks of age to induce osteoporosis and were randomly assigned to two groups : control group (n=8) and calcium-supplemented group (OVX-Ca, n=8). Autologous spinal bone fusion surgery was performed on both groups 8 weeks later. After fusion surgery, the OVX-Ca group was supplemented with calcium in drinking water for 8 weeks. Blood was obtained 4 and 8 weeks after fusion surgery. Eight weeks after fusion surgery, the rats were euthanized and the L4-5 spine removed. Bone fusion status and fusion volume were evaluated by manual palpation and three-dimensional computed tomography. RESULTS: The mean fusion volume in the L4-5 spine was significantly greater in the OVX-Ca group (71.80+/-8.06 mm3) than in controls (35.34+/-8.24 mm3) (p<0.01). The level of osteocalcin, a bone formation marker, was higher in OVX-Ca rats than in controls 4 weeks (610.08+/-10.41 vs. 551.61+/-12.34 ng/mL) and 8 weeks (552.05+/-19.67 vs. 502.98+/-22.76 ng/mL) after fusion surgery (p<0.05). The level of C-terminal telopeptide fragment of type I collagen, a bone resorption marker, was significantly lower in OVX-Ca rats than in controls 4 weeks (77.07+/-12.57 vs. 101.75+/-7.20 ng/mL) and 8 weeks (69.58+/-2.45 vs. 77.15+/-4.10 ng/mL) after fusion surgery (p<0.05). A mechanical strength test showed that the L4-5 vertebrae in the OVX-Ca group withstood a 50% higher maximal load compared with the controls (p<0.01). CONCLUSION: Dietary calcium given to OVX rats after lumbar fusion surgery improved fusion volume and mechanical strength in an ovariectomized rat model.

Effect of a Long-term, Oral Fixed Dose with a Combination of Aledronate and Cacitriol on the Cancellous Bone Microarchitecture in Ovariectomized Rats / 대한정형외과연구학회지

PURPOSE: To study the effect of a long-term, oral, fixed dose with a combination of alendronate and calcitriol on the cancellous bone microarchitecture in an ovariectomized rat model. MATERIALS AND METHODS: Twenty eight female Sprague-Dawley rats were divided into 2 equal groups: a non-medication group (OVX), and a medication group (ALD). The ALD group was treated with an oral daily fixed dose with a combination of alendronate and calcitriol for six months, starting from 4 weeks after ovariectomy, while the OVX group was given only a placebo. After six months, all animals were sacrificed, and an in vitro micro-CT analysis of the the distal femur was performed. The bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), trabecular number (Tb.N), structure model index (SMI), connectivity density (Conn.D), and bone mineral density (BMD) were assessed. RESULTS: The ALD group had significantly higher BV/TV, Tb N, BMD and Conn.D and it also had significantly lower Tb Sp and SMI than the OVX group. CONCLUSION: A long term, daily, oral fixed dose with a combination of alendronate and calcitriol could significantly reduce the osteoporotic changes in this ovariectomized rat model.

Effects of Arginine Supplementation on Bone Mineral Density and Bone Markers in OVX Rats

As far as we know, there were no studies of the effect of L-arginine on bone metabolism in post-menopausal women or ovariectomized rats. The primary objective of the current study was to determine whether arginine supplementation was associated with alterations in femoral and spinal bone mineral density (BMD) and bone markers in ovariectomized (Ovx) rats. Forty female Sprague-Dawley rats were divided into two groups, Ovx and sham groups, which were each randomly divided into two subgroups that were fed control and arginine supplemented diet. All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone formation was measured by serum osteocalcin and alkaline phosphatase (ALP) concentrations. Bone resorption was measured by deoxypyridinoline (DPD) crosslinks immunoassay and corrected for creatinine. Serum osteocalcin, growth hormone, insulin-like growth factor-1 (IGF-1), parathyroid hormone (PTH) and calcitonin were analyzed using radioimmunoassay kits. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin, USA) in spine and femur. The serum and urine concentrations of Ca and P were determined. The plasma was analyzed for arginine. Diet did not affect weight gain, mean food intake, and plasma arginine concentration. Urinary Ca excretion was decreased by arginine supplementation in Ovx rats, but statistically not significant. The Ovx rats fed arginine-supplemented diet were not significantly different in ALP, osteocalcin, crosslinks value, PTH, calcitonin and IGF-1 compared to those fed control diet. The arginine-supplemented group had significantly higher serum Ca and growth hormone than control group. Spine and femur BMD were significantly increased by arginine supplementation on 5th and 9th weeks after feeding. Our findings indicate that dietary L-arginine supplementation decreased bone mineral density loss in Ovx rats. Therefore, dietary arginine supplementation may represent a potentially useful strategy for the management of osteoporosis.

Effects of Ovariectomy and Calcium Intake on Lipid Profile and Antioxidant Capacities in Rats

The purpose of this research was to investigate the effect of the calcium intake on lipid profile and antioxidant capacities in ovariectomized (OVX) rats. Rats were divided into 3 groups and fed diet with different levels of calcium (low 0.1%, adequate 0.5%, high 1.5%) for 4 weeks. The half of rats in each group was ovariectomized and the others were sham-operated. And rats were fed same diets for 8 weeks after operation. Feed intake and weight gain were significantly higher in OVX group than those in sham-operated. Serum HDL-cholesterol was the highest in high-calcium group of OVX. Hepatic triglyceride of low-calcium group in sham-operated was the highest, while that of highcalcium group in OVX was the highest. Hepatic activities of glutathione-S-transferase (GST), glutathione peroxidase (GSH-Px), and catalase were significantly decreased by increasement of calcium intake. Hepatic TBARS level was the lowest in high-calcium group of OVX. And hepatic level of TBARS induced by AAPH was significantly decreased by increasement of calcium intake. These results may indicate that the high calcium intake have the potential role to improve lipid profiles and antioxidant capacities in OVX rats.

In Vitro and In Vivo Effect of Parathyroid Hormone Analogue (1-14) Containing alpha-amino-iso-butyric Acid Residue (Aib)1,3

Firstly, parathyroid hormone (1-14) [PTH (1-14)] analogue containing various alpha-amino-iso-butyric acid residue (Aib) was synthesized by exchanging the 1st and 3rd Ala residues of alpha carbon of PTH (1-14). This analogue revealed to have the quite tight and stable alpha-helical structure using the nuclear magnetic resonance (NMR) analysis. The biological activities of these analogues were examined using a cAMP-generating assay in LLC-PK1 cell lines stably transfected with the wild-type human PTH1 receptor. Only the PTH analogue substituted with methyl moiety without acetylation showed significant cAMP generating action with 15.0 +/- 3.414 of EC50. Then, we used an ovariectomized rat model system to compare the in vivo effects of parathyroid hormone analogue with that of PTH (1-84). Daily subcutaneous administration of the unacetylated Aib1,3PTH (1-14) for 5 weeks in 30 nM/kg subcutaneously with positive control group receiving PTH (1-84) with 8 nM/ kg were performed. However, there was no significant change in spinal or femoral bone mineral density assessed by dual x-ray absorptiometry (DXA) in the Aib1,3PTH (1-14) group where definite increase of these parameters shown in the PTH (1-84) group (p < 0.001). Assessment of bone strength was evaluated with no significant differences among all groups. It was quite disappointing to see the actual discrepancies between the result of significant pharmacokinetic potency and the in vivo clinical effect of the Aib1,3PTH (1-14). However, there are several limitations to mention, such as the short duration of treatment, matter of dosage, and insufficient effect of tight alpha-helical structures with absence of C-terminus. In conclusion, our findings suggest that unacetylated Aib1,3PTH (1-14) did not exhibit any anabolic effects at the bones of ovariectomized rats.

Effects of Boron Supplementation on Lipid Profiles and Antioxidant Capacities in the Ovariectomized Rats

The purpose of this research was to investigate the effect of the boron supplementation on lipid profiles and antioxidant capacities in ovariectomized (OVX) rats. Rats were divided into 3 groups and fed diet with intake levels of boron (0.5 ppm, 50 ppm, 100 ppm) for 4 weeks. The half of rats in each group was ovariectomized and the others were sham-operated. And rats were fed same diets for 8 weeks after operation. Feed intake and weight gain were significantly increased by increasing boron intake and higher in OVX group than those in sham-operated. FER was significantly higher in OVX group than that of sham-operated. There were no significant differences in serum lipid profiles among the groups. The contents of hepatic total lipid were significantly higher in OVX group than those of sham-operated and the lowest in high-boron group. Hepatic GST activity was significantly decreased by ovariectomy and the lowest in very high-boron group. Hepatic catalase activity was the lowest in high-boron group of OVX. Hepatic TBARS level of high-boron group was the lowest in sham-operated groups. Hepatic TBARS level induced by AAPH was significantly decreased by increasement of boron supplementation. Taken together, this results suggest that the boron supplementation have the potential role for improving lipid profiles and antioxidant capacities in OVX rats.

Effect of Eucommiae ulmoides on the Microstructural and Ultrastructural Structure of Femur and Lumbar Vertebrae in Ovariectomized Rats / 中国药房

OBJECTIVE: To evaluate the effect of Eucommiae ulmoides on the microstructural and ultrastructural change of femur and lumber vertebrae in ovariectomized rats.METHODS: 80 4-month-old female SD rats were randomized to 4 groups: sham operation group,model group,alfacalcidol group,E.ulmoides group.In the sham operation group,the abdominal cavities of the rats were cut open to expose ovaries before being sutured.However,the rats in the other 3 groups were ovariectomized bilaterally.At 10 days after operation the rats were administered intragastrically with corresponding drug.After 3 months,femur and lumber vertebrae were dissected and fixed in 4% glutaral for 3 days,then decalcified in 4% EDTA for 4 weeks,and then the structure of femur and lumber vertebrae was observed under light microscope and transmission electron microscope(TEM).RESULTS: Observed under light microscope,the femur and lumber vertebrae were full of fat in the ovariectomized rats and in which the density of bone trabecula decreased significantly;however,in alfacalcidol-treated rats and E.ulmoides-treated rats,the amount of fat decreased markedly while the density and thickness of bone trabecula increased.Observed under TEM,in the ovariectomized rats,rough endoplasmic reticulum(RER),cytolysosome and mitochondrial were plentiful inside osteoclasts in femur and lumber vertebrae,partial osteoblasts atrophied,the amount of RER and other cellular organ decreased significantly and apoptosis appeared for partial cells;however,in alfacalcidol-treated group and E.ulmoicdes-treated group,the above changes improved significantly.CONCLUSION:E.ulmoides has remarkable beneficial effect on osteoporosis in ovariectomized rats.The mechanism might be attributed to its inhibition on the synthesis of fat and the activity of osteoclasts,promotion on the activity of osteoblasts and inhibition on the apoptosis.

Effects of Red-Yeast-Rice Supplementation on Bone Mineral Density and Bone Mineral Content in Overiectomized Rats

This study was performed to evaluate the effect of red-yeast-rice on bone metabolism in overiectomized (OVX) rats. Forty female Sprague-Dawley rats (body weight 210 +/- 5 g, 9 weeks old age) were divided into two groups. One group were OVX, and the other group received sham operation (SHAM), and received either control diet (20% casein) or a red-yeast-rice power supplemented diet (0.1%) for 9 weeks. And then each rat group was further divided into control diet (casein 20%) and red-yeast-rice powder supplemented (0.1%) diet group. All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin, USA) in spine and femur on 5, 9 weeks after feeding. The serum and urine concentrations of Ca and P were determined. Bone formation was measured by serum osteocalcin and alkaline phosphatase (ALP) concentrations. And bone resorption rate was measured by deoxypyridinoline (DPD) crosslinks immunoassay and corrected for creatinine. Serum osteocalcin, growth hormone, IGF-1 and calcitonin were analyzed using radioimmunoassay kits. Urinary Ca and P excretion were not significantly different among the groups. Within the OVX group, the red-yeast-rice group had a lower crosslinks value than the casein group. Therefore the redyeast- rice supplemented groups had a lower bone resorption ratio than the casein group in the ovariectomized rats. And, the red-yeast-rice group had significantly higher IGF-1 hormone than casein group in ovariectomized rats. The redyeast-rice group had higher spine bone mineral content than those of control group within the OVX groups. This study was an important first step in establishing that the observed beneficial effects of red-yeast-rice on bone, and this study also established the need for a study on the long-term effect of this supplement in a human.

Effect of Estrogen to Antioxidant Enzymes in Rat Erythrocyte / 대한산부인과학회잡지

OBJECTIVE: To observe whether any relationship exists between the consentration of plasma estradiol (E2) and the plasma consentration of malondialdehyde (MDA) or whether a relationship exists between the consentration of plasma E2 and the activity of erythrocyte enzymes, superoxide dismutase (SOD) and catalase, in ovariectomized female rats. METHODS: We used 40 ovariectomized Sprague-Dewley rats randomly assigned to four groups. The first group (group A) was allowed to evolve freely with no estrogen supply. A gel containing 17beta-estradiol was administered transdermally to the other three groups at dose of 5 micro gram/day (group B), 10 micro gram/day (group C) and 15 micro gram/day (group D). After 2 weeks of recovery date from operation and 4 weeks of estrogen treatment, blood samples were obtained from the four groups. The concentrations of plasma E2 and MDA and the concentrations of erythrocyte catalase and SOD were determined. RESULTS: There were significant correlations between the plama E2 concentrations and the concentrations of erythrocytes catalase and SOD in the group C, D. Whereas catalase and SOD activities in erythrocytes was decreased in estrogen replacement group. Any relationship wasn't found between the E2 concentrations and the plasma MDA levels in all groups. CONCLUSION: Thiese result suggested that the catalase and SOD in erythrocytes is related the plasma E2 concentration. This model may explain the contradictory findings presented by estrogens with respect to their pro-or antioxidant action. The further study will be needed to evaluate the effect of estrogen induced plasma lipid peroxidation.

Effect of Estrogen to Antioxidant Enzymes in Rat Erythrocyte / 대한산부인과학회잡지

OBJECTIVE: To observe whether any relationship exists between the consentration of plasma estradiol (E2) and the plasma consentration of malondialdehyde (MDA) or whether a relationship exists between the consentration of plasma E2 and the activity of erythrocyte enzymes, superoxide dismutase (SOD) and catalase, in ovariectomized female rats. METHODS: We used 40 ovariectomized Sprague-Dewley rats randomly assigned to four groups. The first group (group A) was allowed to evolve freely with no estrogen supply. A gel containing 17beta-estradiol was administered transdermally to the other three groups at dose of 5 micro gram/day (group B), 10 micro gram/day (group C) and 15 micro gram/day (group D). After 2 weeks of recovery date from operation and 4 weeks of estrogen treatment, blood samples were obtained from the four groups. The concentrations of plasma E2 and MDA and the concentrations of erythrocyte catalase and SOD were determined. RESULTS: There were significant correlations between the plama E2 concentrations and the concentrations of erythrocytes catalase and SOD in the group C, D. Whereas catalase and SOD activities in erythrocytes was decreased in estrogen replacement group. Any relationship wasn't found between the E2 concentrations and the plasma MDA levels in all groups. CONCLUSION: Thiese result suggested that the catalase and SOD in erythrocytes is related the plasma E2 concentration. This model may explain the contradictory findings presented by estrogens with respect to their pro-or antioxidant action. The further study will be needed to evaluate the effect of estrogen induced plasma lipid peroxidation.

Effects of epimedium pubescens flavonoids on skeleton of ovariectomized rats / 中国临床药理学与治疗学

AIM: To study the effects of epimedium pubescens flavonoids (EF) on the skeleton in ovariectomized rats. METHODS: Forty 4.5-month-old Sprague-Dawley female rats were randomly divided into 4 groups. Rats in sham group were sham-operated and treated by daily oral gavage with vehicle. Rats in other three groups were bilaterally ovariectomized (OVX) and treated by either daily oral gavage with vehicle, or diethylstilbestrol (DES) at 22.5 ?g?kg~ -1?d~ -1, or EF at 300 mg?kg~ -1?d~ -1 for 90 days. Bone histomorphometric analysis of the proximal tibial metaphysis (PTM), fifth lumbar vertebrae (LV5) and tibial shaft (Tx) was performed in undecalcified sections. The left femur was collected to determine bone weight, contents of calcium (Ca) , phosphorus (P ) and hydroxyproline. The uterine weight and the uterine luminal epithelial thickness (ULET) were determined. RESULTS: A significant increase in contents of Ca and P of femur was found in EF group. A tendency of increase was found in %Tb.Ar of PTM, but no significant change was found in bone histomorphometric parameters of LV5 and Tx in EF group. EF had no effect on uterine weight and ULET. CONCLUSION: EF can prevent OVX-induced bone mineral loss of femur, but does not prevent bone loss of PTM and LV5.

Effect of pulsed electromagnetic fields of different daily treatment durations on biomechanical properties of femur in ovariectomized rats / 中华物理医学与康复杂志

Objective To observe the effect of pulsed electromagnetic fields(PEMFs)of different daily treatment durations on biomechanical properties of femur in ovariectomized rats,so as to find out the optimal daily treatment time.Methods Fifty female Sprague-Dawley rats were randomly divided into five groups:(1)SHAM control(no PEMFs treatment),(2)OVX control(no PEMFs treatment),(3)OVX I(PEMFs treatment at 8Hz fre- quency with 3.8 mT intensity,20 min daily for 30 days),(4)OVX 11(PEMFs treatment at 8 Hz frequency with 3.8 mT intensity,40 min daily for 30 days),and(5)OVXⅢ(PEMFs treatment at 8Hz frequency with 3.8 mT in- tensity,60 rain daily for 30 days).All the rats were subject to bilateral overiectomy except those in the SHAM control group.The biomechanical properties of the femur were assessed after 30 days of PEMFs treatment.Results The values of the parameters of the biomechanical properties obtained with the OVX control group were significantly lower than those of the other 4 groups(P0.05).Conclusion PEMFs of the three different daily treatment durations can maintain the biomechanical properties of the femur in ovariectomized rats.Under certain in- tensity(3.8 mT)and frequency(8 Hz),PEMFs of the three different treatment durations can significantly maintain biomechanical properties of femur in ovariectomized rats approximately to the nomal level,but among the three groups,the difference is not significant.It was shown that exposure to PEMFs for 20 to 60 minutes daily had similar effect of maintaining biomechanical properties of the femur in ovariectomized rats.

The Effect of Isoflavone and/or Grape Seed Oil Supplementation on Blood Lipid Profiles and Bone Strength in Ovariectomized Female Rats

The study was performed to investigate the effects of isoflavone and/or grape seed oil supplementation on serum and liver lipid profiles and bone strength in ovariectomized female rats. Female Spraque-Dawley rats were assigned into 4 groups of ovariectomized (O), isoflavone (0.085 mg/100 g b.w/day) in ovariectomized rats, grape seed oil in ovariectomized rats and isoflavone and/or grape seed oil in ovariectomized rats. After 8 weeks, biochemical profiles of serum, liver and bone were analyzed. Total food intakes, body weight gains and FER (food efficiency ratio) were not statistically significantly different among groups. Total cholesterol, triglyceride and LDL-cholesterol levels in serum were decreased by fed of isoflavone and/or grape seed oils. However, crude lipid and total cholesterol contents in liver were not affect of isoflavone and/or grape seed oil. The hepatic glutathione contents were increased by isoflavone and/or grape seed oil fed. The hepatic glutathione-S-transferase activity in isoflavone and/or grape seed oil supplemented groups were higher than that O group. Bone (scapular and femur bone) dry weight, femur of max weight and bending strength were no significant difference among groups. Our finding suggest that isoflavone/grape seed oils might have potential role for serum lipid profiles improvement and bone strength in vivo.

Combination of norethisterone with ethinylestradiol showed synergetic effect on ovariectomy induced osteopeniain rats / 中国药理学通报

AIM To determine whether norethisterone in combination with ethinylestradiol can completely prevent bone loss in ovariectomized rats. METHODS Twenty-four Sprague-Dawley female rats at the age of 4.5 months were sham-operated and treated orally with vehicle, or ovariectomized (OVX) and treated orally with either vehicle or combined norethisterone (norethisterone at 60 ?g?kg -1?d -1 and ethinylestradiol at 3.5 ?g?kg -1?d -1) for 90 days. Double in vivo fluorochrome labeling was administrated. The undecalcified longitudinal proximal tibial metaphyseal sections were used for the bone histomorphometric analysis. The humerus and urine calcium contents were assayed by the method of atomic absorption spectrometry. The humerus and urine hydroxyproline contents were assayed by colorimetry. Blood serum alkaline phosphatase (ALP) were tested by BECKMAN auto bio-chemistry analyzer. RESULTS After 90 days post OVX the cancellous bone mass and showed high bone turnover indices. Bone hydroxyproline contents were lost markedly. The ALP activity increased. The urine hydroxyproline contents increased significantly. The combined norethisterone treated group prevented bone lost when compared with OVX. The combined norethisterone were shown to inhibit osteoclasts surface and decrese bone turnover rate. The combined norethisterone can increase hydroxyproline contents and reduce urine hydroxyproline contents significantly from OVX group. CONCLUSION Combining norethisterone can prevent OVX-induced cancellous bone loss in rats.