scholarly journals Effect of Ovariectomy on Stimulating Intracortical Remodeling in Rats

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Chun Lei Li ◽  
Xi Ling Liu ◽  
Wei Xin Cai ◽  
Weijia William Lu ◽  
Roger A. Zwahlen ◽  
...  

Objective.Technically primates and dogs represent ideal models to investigate diseases characterized by abnormal intracortical remodeling. High expenses and ethical issues, however, restrict the use of those animals in research. Rodent models have been used as alternatives instead, but their value is limited, if none, because these animals lack intracortical bone remodeling. This study aimed at investigating the effect of ovariectomy onto the stimulation of intracortical remodeling in rat mandibles.Materials and Methods.Sixteen 12-week-old Spraque-Dawly (SD) female rats were randomly assigned into two groups, receiving either ovariectomy or sham operation. All the rats were sacrificed 18 weeks postoperatively. The entire mandibles were harvested for microcomputed tomography (micro-CT) and histomorphometric assessments.Results.Micro-CT examination showed significantly decreased bone mineral density (0.95 ± 0.01 versus 1.01 ± 0.02 g/cm3,P<0.001) and bone volume (65.78 ± 5.45 versus 87.41 ± 4.12%,P<0.001) in ovariectomy group. Histomorphometric assessment detected a sixfold increased intracortical bone remodeling as well as an increased bone modeling in mandibles of ovariectomized rats.Conclusion.For the first time, to the authors’ knowledge, it was detected that ovariectomy stimulates intracortical remodeling in rat mandibles. This animal model might be of use to study various bone diseases associated with an abnormal intracortical remodeling process.

2003 ◽  
Vol 31 (01) ◽  
pp. 87-101 ◽  
Author(s):  
Min Xu ◽  
Ian M. Dick ◽  
Robert Day ◽  
Drew Randall ◽  
Richard L. Prince

For many decades, the Chinese have been using herbal medications to treat bone diseases. To examine effects of an extract of ten medicinal herbs on estrogen deficiency bone loss, ten-month-old female rats were randomly divided into three groups: ovariectomized (OVX), OVX treated with herbs (OVX-M) 4 ml/day by gavage, and OVX treated with estrogen (OVX-E) 10 mg subcutaneously (s.c.) twice per week. The bone mineral density (BMD) of the left femur (fBMD), spine (sBMD) and global body (gBMD) were measured at baseline and at 4, 8 and 12 weeks using a Hologic QDR 2000 dual-energy X-ray densitometer. Tibial strength was tested using the Instron Model 5566 electro-mechanical testing machine. The urinary pyridinoline creatinine ratio (Pyd/Cr), deoxypyridinoline creatinine ratio (Dpd/Cr), plasma alkaline phosphatase (ALP), calcium (CA), phosphorus (P) and albumin (ALB) were also determined. Uterine weight was determined at 12 weeks. The results showed that percent changes of fBMD in the OVX (n = 9), OVX-E (n = 8) and OVX-M (n = 8) rats at the 12-week time point were -11.8 ± 4.6c, 1.8 ± 3.1a, -7.6 ± 1.9abc (p < 0.05-0.001, a: vs. OVX, b: vs. OVX-E, c: vs. baseline); sBMD were -10.7 ± 4.6c, -0.3 ± 5.5a, -5.9 ± 3.5abc; and gBMD were -4.8 ± 2.3c, 0.1 ± 2.4a, -2.7 ± 2.6abc, respectively. Further, the tibia maximum breaking stress and flexural modulus of elasticity in OVX-M rats (295 ± 33a, 18194 ± 3264a) were significantly higher (p < 0.005-0.001) than that in OVX rats (189 ± 83, 10309 ± 4930), and similar to OVX-E rats (298 ± 35a, 18766 ± 2620a). Additionally, the herbal extract reduced the urinary Pyd/Cr, Dpd/Cr and plasma ALP increment followed OVX and was not associated with a rise in uterine weight. In conclusion, the herbal extract demonstrated a therapeutic effect to inhibit bone resorption and to reduce estrogen-dependent bone loss without uterine stimulation. It may have potential as a new approach in treating and preventing postmenopausal osteoporosis (PMOP).


2021 ◽  
Author(s):  
Zhoushan Tao

Abstract Objective: the present work was aimed to evaluate the effect of different administration modes of sodium valproate(VPA) on bone strength, bone mass and bone mineral density in ovariectomized(OVX) rats and further investigation of the possible mechanism. Methods: 60 female SD rats were randomly divided into 4 groups: Sham group (Sham, n=15), OVX group (OVX, n=15), OVX rats received intermittent VPA treatment group(IVPA, n=15) and OVX rats received daily VPA treatment group(EVPA, n=15). After 12 weeks of treatment, the rats were sacrificed, and serum and femur samples were harvested. DEXA, Micro-CT, histology, biomechanical testing, biochemical index and western blot analysis were used to observe the therapeutic effect and explore the possible mechanism. Results: Micro-CT and DEXA analysis of bones revealed better BMD and higher BV/TV, Tb.Th, Tb.N, Conn. D and lower Tb.Sp at femoral metaphysis with evaluated in IVPA when compared with OVX and EVPA group(P<0.05). Histological, fluorescent analysis and biological strength revealed more trabecular bone and higher relative mineral apposition rate, maximal load, elastic modulus and energy at break with evaluated in IVPA when compared with OVX and EVPA group(P<0.05). The levels of P1NP, estrogen, CTX, TRAP5b and RANKL of IVPA group showed a significant increase when compared with the OVX and EVPA group(P<0.05). We confirm adverse effects on protein expressions including Notch1, Jagged1, HEY1, Wnt 1, β‐catenin and RUNX2 following daily VPA treatment in OVX female rats. Conclusions: Our current study demonstrated that intermittent administration sodium valproate has a protective effect on bone health in ovariectomized rats and these effects may be achieved by activating Notch/Wnt/β-catenin/ RUNX2 signal axis.


2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Shenzhi Xu ◽  
Hideyuki Okano ◽  
Naohide Tomita ◽  
Yoshito Ikada

The effects of a moderate-intensity static magnetic field (SMF) on osteoporosis of the lumbar vertebrae were studied in ovariectomized rats. A small disc magnet (maximum magnetic flux density 180 mT) was implanted to the right side of spinous process of the third lumbar vertebra. Female rats in the growth stage (10 weeks old) were randomly divided into 4 groups: (i) ovariectomized and implanted with a disc magnet (SMF); (ii) ovariectomized and implanted with a nonmagnetized disc (sham); (iii) ovariectomized alone (OVX) and (vi) intact, nonoperated cage control (CTL). The blood serum 17--estradiol (E2) concentrations were measured by radioimmunoassay, and the bone mineral density (BMD) values of the femurs and the lumbar vertebrae were assessed by dual energy X-ray absorptiometry. The E2concentrations were statistically significantly lower for all three operated groups than those of the CTL group at the 6th week. Although there was no statistical significant difference in the E2concentrations between the SMF-exposed and sham-exposed groups, the BMD values of the lumbar vertebrae proximal to the SMF-exposed area statistically significantly increased in the SMF-exposed group than in the sham-exposed group. These results suggest that the SMF increased the BMD values of osteoporotic lumbar vertebrae in the ovariectomized rats.


2020 ◽  
Vol 10 (17) ◽  
pp. 6131
Author(s):  
Parkpoom Siriarchavatana ◽  
Marlena C. Kruger ◽  
Matthew R. Miller ◽  
Hong (Sabrina) Tian ◽  
Frances M. Wolber

The prevalence of metabolic osteoarthritis has been increasing worldwide, particularly among women. The aim of this study was to investigate the effects of the New Zealand greenshell mussel (Perna canaliculus; GSM) on osteoarthritis (OA) prevention in a rat model. One-hundred-and-eight female rats aged 12 weeks were divided into four test groups, containing 24 rats each, plus an additional control group. Each test group received one of the four experimental diets: normal control diet (ND), normal control diet supplemented with GSM (ND + GSM), high fat/high sugar diet (HFHS), or high fat/high sugar diet supplemented GSM (HFHS + GSM), for 36 weeks (end of the study). After 8 weeks on experimental diets, half of each group was subjected to ovariectomy (OVX) and the remaining half received a sham operation (ovaries left intact). The study evaluated body composition, bone mass, plasma cytokines, adipokines, HbA1c, CTX-II, and knee joint’s histopathology. HFHS diet and OVX significantly induced body weight gain and leptin production. OVX rats lost bone mineral density but increased adiponectin, HbA1C, and MCP-1. The OVX rats fed HFHS showed the highest Mankin scores. Importantly, inclusion of GSM reduced these pathological features. In conclusion, GSM might be beneficial in halting the progression of OA.


2001 ◽  
Vol 86 (4) ◽  
pp. 521-527 ◽  
Author(s):  
Joseé Gala ◽  
Manuel Di´az-curiel ◽  
Concepcioó de la Piedra ◽  
Jesu´s Calero

At the level of prevention of bone mineral loss produced by ovariectomy, the aim of the present study was to determine the effect produced by supplementation of Ca in the diet and a moderate exercise programme (treadmill), simultaneously or separately, in ovariectomized rats, an experimental model of postmenopausal bone loss. Female Wistar rats (n110, 15 weeks old) were divided into five groups: (1) OVX, rats ovariectomized at 15 weeks of age, fed a standard diet; (2) SHAM, rats sham operated at 15 weeks of age, fed a standard diet; (3) OVX–EX, ovariectomized rats, fed a standard diet and performing the established exercise programme; (4) OVX–Ca, ovariectomized rats fed a diet supplemented with Ca; (5) OVX–EXCa, ovariectomized rats with the exercise programme and diet supplemented with Ca. The different treatments were initiated 1 week after ovariectomy and were continued for 13 weeks for subgroup 1 and 28 weeks for subgroup 2, to look at the interaction of age and time passed from ovariectomy on the treatments. Bone mineral density (BMD) was determined, at the end of the study, in the lumbar spine (L2, L3 and L4) and in the left femur using a densitometer. Bone turnover was also estimated at the end of the study, measuring the serum formation marker total alkaline phosphatase (AP) and the resorption marker serum tartrate-resistant acid phosphatase (TRAP). As expected, OVX rats showed a significant decrease (P<0·05) in BMD, more pronounced in subgroup 2, and a significant increase in AP and TRAP with regard to their respective SHAM group. The simultaneous treatment with Ca and exercise produced the best effects on lumbar and femoral BMD of ovariectomized rats, partially avoiding bone loss produced by ovariectomy, although it was not able to fully maintain BMD levels of intact animals. This combined treatment produced a significant increase in AP, both in subgroups 1 and 2, and a decrease in TRAP in subgroup 1, with regard to OVX group. The exercise treatment alone was able to produce an increase in BMD with regard to OVX group only in subgroup 1 of rats (younger animals and less time from ovariectomy), but not in subgroup 2. In agreement with this, there was an increase of AP in both subgroups, lower than that observed in animals submitted to exercise plus Ca supplement, and a decrease of TRAP in subgroup 1, without significant changes in this marker in the older rats. Ca treatment did not produce any significant effect on BMD in OVX rats in both subgroups of animals, showing a decrease of AP and TRAP levels in the younger animals with no significant variations in markers of bone remodelling in the older female rats compared with their respective OVX group.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
He Zhang ◽  
Ying Dong ◽  
Bin Qi ◽  
Li Liu ◽  
Guangxin Zhou ◽  
...  

Deer sinew (DS) has been used traditionally for various illnesses, and the major active constituent is collagen. In this study, we assessed the effects of collagen peptide from DS on bone loss in the ovariectomized rats. Wister female rats were randomly divided into six groups as follows: sham-operated (SHAM), ovariectomized control (OVX), OVX given 1.0 mg/kg/week nylestriol (OVX + N), OVX given 0.4 g/kg/day collagen peptide (OVX + H), OVX given 0.2 g/kg/day collagen peptide (OXV + M), and OVX given 0.1 g/kg/day collagen peptide (OXV + L), respectively. After 13 weeks of treatment, the rats were euthanized, and the effects of collagen peptide on body weight, uterine weight, bone mineral density (BMD), serum biochemical indicators, bone histomorphometry, and bone mechanics were observed. The data showed that BMD and concentration of serum hydroxyproline were significantly increased and the levels of serum calcium, phosphorus, and alkaline phosphatase were decreased. Besides, histomorphometric parameters and mechanical indicators were improved. However, collagen peptide of DS has no effect on estradiol level, body weight, and uterine weight. Therefore, these results suggest that the collagen peptide supplementation may also prevent and treat bone loss.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Zhiguo Zhang ◽  
Jiazi Dong ◽  
Meijie Liu ◽  
Yan Li ◽  
Jinghua Pan ◽  
...  

The aim of this study was to evaluate effects of aqueous extract fromCortex acanthopanacis(CAE) on osteoporosis rats induced by ovariectomy (OVX) using aqueous extract fromFolium Epimedii(FEE) as positive control agent. Three-month-old female rats that underwent OVX were treated with CAE. After 12 weeks, bone mineral density (BMD) and indices of bone histomorphometry of tibia were measured. Levels of protein and mRNA expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) in tibia were evaluated. In addition, the serum concentrations of osteocalcin (OC), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), calcitonin (CT), and parathyroid hormone (PTH) were determined. Administration of CAE significantly prevented OVX-induced rats from gain of the body weight. Treatment with CAE increased bone mass remarkably and showed a significant inhibitory effect on bone resorption by downregulating significantly the expression of RANKL in tibia of OVX rats. Meanwhile, treatment of CAE significantly reduced serum level of IL-1βand increased level of CT in OVX rats. This suggests that CAE has the potential to be used as an alternative therapeutic agent for postmenopausal osteoporosis.


2003 ◽  
Vol 95 (3) ◽  
pp. 1032-1037 ◽  
Author(s):  
Akiko Honda ◽  
Naota Sogo ◽  
Seigo Nagasawa ◽  
Takuya Shimizu ◽  
Yoshihisa Umemura

The effect of jump exercise on middle-aged osteopenic rats was investigated. Forty-two 9-mo-old female rats were either sham-operated (Sham) or ovariectomized (OVX). Three months after surgery, the rats were divided into the following groups: Sham sedentary, Sham exercised, OVX sedentary, and OVX exercised. Rats in the exercise groups jumped 10 times/day, 5 days/wk, for 8 wk, with a jumping height of 40 cm. Less than 1 min was required for the jump training. After the experiment, the right tibia and femur were dissected, and blood was obtained from each rat. OVX rats were observed to have increased body weights and decreased bone mass in their tibiae and femurs. Jump-exercised rats, on the other hand, had significantly increased tibial bone mass, strength, and cortical areas. The bone mass and strength of OVX exercised rats increased to approximately the same extent as Sham exercised rats, despite estrogen deficiency or osteopenia. Our data suggest that jump exercise has beneficial effects on lower limb bone mass, strength, bone mineral density, and morphometry in middle-aged osteopenic rats, as well as in Sham rats.


2018 ◽  
Vol 67 (3) ◽  
pp. 169-184 ◽  
Author(s):  
Tomoka Hasegawa ◽  
Tomomaya Yamamoto ◽  
Sadaoki Sakai ◽  
Yukina Miyamoto ◽  
Hiromi Hongo ◽  
...  

Summary Intermittent administration of human parathyroid hormone (1-34) (hPTH(1-34)) promotes anabolic action in bone by stimulating bone remodeling, while eldecalcitol, an analog of active vitamin D3, suppresses osteoclastic bone resorption, and forms new bone by minimodeling. We have examined the biological effects of combined administration of eldecalcitol and hPTH(1-34) on 9-week-old Wistar rats that underwent an ovariectomy (OVX) or Sham operation. They were divided into a Sham group, OVX with vehicle (OVX group), OVX with 10 µg/kg/day of hPTH(1-34) (PTH group), OVX with 20 ng/kg/day of eldecalcitol (eldecalcitol group) or OVX with 10 μg/kg/day of hPTH(1-34), and 20 ng/kg/day of eldecalcitol (combined group) for 4 or 8 weeks. As a consequence, the combined group showed a marked increase in bone volume/tissue volume (BV/TV), trabecular thickness (Tb.Th), and trabecular number (Tb.N) than OVX and had the highest bone mineral density (BMD) compared with other groups. OVX and PTH groups exhibited a high osteoblastic surface/bone surface (Ob.S/BS), mineral apposition rate (MAR), and bone formation rate/bone surface (BFR/BS) indices and many TRAP-reactive osteoclasts. Contrastingly, eldecalcitol and combined groups tended to attenuate the indices of osteoclastic surface/bone surface (Oc.S/BS) and Ob.S/BS than that the other groups. The combined group revealed histological profiles of minimodeling- and remodeling-based bone formation. Thus, the combined administration of eldecalcitol and hPTH(1-34) augments their anabolic effects by means of minimodeling and remodeling.


Sign in / Sign up

Export Citation Format

Share Document