Bone Metabolism In Ovariectomized Rats Research Articles

Effect of antidepressants on bone mineral density and bone metabolism in ovariectomized depressed rats

Purpose: To investigate the effect of antidepressants on bone mineral density and bone metabolism in ovariectomized rats with depression. Methods: 48 female rats were randomly and equally assigned to six groups, namely, sham (Sn), ovariectomized depression (OD), ovariectomized depression rats treated with sertraline (ODs), citalopram (ODx), reboxetine (ODr), and venlafaxine groups (ODw). Behavioral alterations and bone-related parameters were evaluated before and after treatment. Results: After treatment, ODs, ODx, ODw, and ODr groups had higher levels of horizontal and vertical exercise scores, sugar water consumption, osteoclasts, and serum CTX-1 (p < 0.05) compared to OD group. Osteocytes, serum serotonin (5-HT), osteocalcin (BGP), and type I procollagen N-terminal propeptide (PINP) were significantly decreased (p < 0.05) after treatment in ODs, ODx, ODw, and ODr groups. A positive correlation was observed between 5-HT, BGP, PINP, and whole-body bone mineral density (r = 0.931, 0.907, and 0.843, p < 0.05) respectively, while a negative correlation was observed between collagen type I C-terminal propeptide (CTX-I) and bone mineral density (r = -0.855, p < 0.05). Conclusion: Antidepressants reduce bone mineral density and osteocyte proliferation, while increasing osteoclast proliferation. These effects are associated with reductions in 5-HT, PINP and BGP levels, and increase in CTX-I.

Anti-osteoporotic effects of Yi Mai Jian on bone metabolism of ovariectomized rats.

Yi Mai Jian herbal formula (YMJ) is formulated with Eucommiae Folium, Astragali Radix, Ligustri Lucidi Fructus, and Elaeagnus Fructus to improve bone function in traditional Chinese medicine. The anti-osteoporotic effects of YMJ in bone metabolism were evaluated in ovariectomized (OVX) rats. The skeletal structure of the femur and vertebrae was analyzed after treating OVX rats with YMJ for 114days. The results showed that YMJ significantly increased the bone mineral density (BMD) and trabecular number (Tb. N) of the femur and 5th lumbar vertebrae and reduced trabecular separation (Tb. Sp). Moreover, trabecular bone volume/total tissue volume (BV/TV), bone stiffness, and maximum femur load were significantly increased. The serum concentrations of NTX1 and PYD were significantly decreased. According to these results, YMJ could ameliorate osteoporosis in ovariectomized rats. Eucommiae Folium and Elaeagnus Fructus inhibited osteoclast differentiation, Ligustri Lucidi Fructus inhibited calcium reabsorption, Astragali Radix stimulated osteoblast proliferation, and Astragali Radix and Eucommiae Folium stimulated mineralization. Therefore, the combination of the four herbs into one formula, YMJ, could alleviate bone remodeling caused by low estrogen levels. We suggest that YMJ could be a healthy food candidate for preventing post-menopausal osteoporosis.

Effect of Tempeh and Daidzein on Calcium Status, Calcium Transporters, and Bone Metabolism Biomarkers in Ovariectomized Rats.

Menopause marks a critical life stage characterized by hormonal changes that significantly impact bone health, leading to a heightened susceptibility to bone fractures. This research seeks to elucidate the impact of daidzein and tempeh on calcium status, calcium transporters, and bone metabolism in an ovariectomized rat model. Forty female Wistar rats, aged 3 months, participated in a two-phase experiment. The initial phase involved inducing a calcium deficit, while the second phase comprised dietary interventions across five groups: Sham (S) and Ovariectomy (O) with a standard diet, O with bisphosphonate (OB), O with pure daidzein (OD), and O with tempeh (OT). Multiple parameters, encompassing calcium levels, calcium transporters, bone histopathology, and serum bone metabolism markers, were evaluated. The findings revealed that the OT group showcased heightened levels of bone turnover markers, such as pyridinoline, C-telopeptide of type I collagen, bone alkaline phosphatase, and procollagen type I N-terminal propeptide, in contrast to S and O groups, with statistical significance (p < 0.05). Histopathologically, both the OD and OT groups exhibited effects akin to the OB group, indicating a decrease in the surface area occupied by adipocytes in the femoral bone structure, although statistically non-equivalent, supporting the directionally similar trends. Although TRPV5 and TRPV6 mRNA expression levels in the jejunum and duodenum did not display statistically significant differences (p > 0.05), the OD and OT groups exhibited increased expression compared to the O group. We hypothesized that obtained results may be related to the effect of isoflavones on estrogen pathways because of their structurally similar to endogenous estrogen and weak estrogenic properties. In conclusion, the daily consumption of pure daidzein and tempeh could potentially improve and reinstate calcium status, calcium transport, and bone metabolism in ovariectomized rats. Additionally, isoflavone products demonstrate effects similar to bisphosphonate drugs on these parameters in ovariectomized rats.

Effects of Aronia melanocarpa fruit juice on lipid and bone metabolism in ovariectomized rats

Introduction: The ovariectomized (OVX) rat is a gold-standard model to mimic the changes in the female organism during menopause. Aronia melanocarpa fruits are very rich in polyphenols and exert many beneficial effects in animal models and clinical trials. Aim: The aim of the present study was to investigate the effects of Aronia melanocarpa fruit juice (AMFJ) on lipid metabolism and bone mineral density (BMD) in OVX rats. Materials and Methods: Four groups of female Wistar rats were formed, each consisting of 14 animals—sham operated (SO), OVX (treated with distilled water), as well as OVX+AMFJ 5 , and OVX+AMFJ 10 (OVX treated with 5 and 10 mL/kg AMFJ, respectively). The animal treatment began 2 weeks after the operation. After a three-month treatment period, body weight (BW), total fat (TF) and retroperitoneal fat (RPF), as well as serum total cholesterol were measured. The indices TF/BW and RPF/BW were calculated. Femur BMD was determined as well. The statistical analysis used was one-way ANOVA. Results: Compared to SO animals, OVX rats showed a statistically significant increase in TF (p &lt; 0.05), RPF (p &lt; 0.01), TF/BW (p &lt; 0.05), and RPF/BW (p &lt; 0.01). Plasma cholesterol levels of OVX animals were increased and their BMD was decreased if compared to SO rats, but these changes were not statistically significant. Compared to OVX rats, AMFJ did not affect lipid accumulation and cholesterol levels but at the dose of 10 mL/kg significantly increased BMD (p &lt; 0.05 vs. OVX). Conclusion: Aronia melanocarpa fruit juice was not able to prevent the fat accumulation in OVX rats, but managed to restore their BMD.

Effect of amlodipine and L-carnitine on bone metabolism in ovariectomized rats

Background Amlodipine as a calcium channel blocker has anti-inflammatory effect through overaugmentation of nitric oxide production and antioxidant effect by reduced superoxide radicals and increased level of superoxide dismutase. l-carnitine has anti-inflammatory action through reaction with acyl group that is accumulated in anoxic cells and antioxidant effect through decreasing the superoxide anion production. Aim The aim was to evaluate the possible ameliorating effect of amlodipine (AML) and L-Carnitine (L-C) combination on osteoporotic bony changes in ovariectomized (OVX) rats versus each drug separately. A total of 50 adult female albino rats (weighting 100–125 g) of local strain were chosen as an animal model for this study. The animals were randomly divided into five groups. Each group comprised ten rats: group 1, negative control; group 2, OVX rats, positive control; group 3, AML-treated OVX rats; group 4, L-C-treated OVX rats, and group 5, AML and L-C-treated OVX rats. Bony changes were examined through evaluating markers of bone turnover, such as alkaline phosphatase and osteocalcin; femoral metaphyseal histomorphology; and serum proinflammatory cytokines, such as tumor necrosis factor-α, expression. Results alkaline phosphatase, osteocalcin, and tumor necrosis factor-α were significantly elevated in positive control group, which was associated with marked deterioration of bone microarchitecture. Treatment with AML and L-C combination significantly mitigated inflammation and histopathological osteoporotic changes compared with each of AML and L-C drugs separately. Conclusion AML and L-C combination could have a synergistic role in management of radical osteoporosis in OVX rats over each drug separately.

The Effects of Ficus Carica Fruit on Bone Markers and Oestrogen Level of Post-Menopausal Osteoporotic Rats

Introduction: Post-menopausal osteoporosis is the most common type of osteoporosis, which occurs due to a deficiency of oestrogen following menopause. Considering the adverse effects of oestrogen replacement therapy, natural products may serve to replace the current conventional treatment. Ficus carica (FC) which is commonly known as fig may have a potential in treating post-menopausal osteoporosis due to their abundance of important minerals and bioactive compounds such as phenolic, flavonoid and anthocyanins. This study aimed to evaluate the effects of FC on bone metabolism of ovariectomized rats. Materials and Methods: Fifty-six female Spraque-Dawley rats were randomly divided into seven groups; SHAM operated (SHAM), ovariectomized control (OVX), ovariectomized + 64.5 µg/kg oestrogen (ERT), ovariectomized + 50 mg/kg aqueous extract of FC (AQ50), ovariectomized + 100 mg/kg aqueous extract of FC (AQ100), ovariectomized + 50 mg/kg raw FC (RW50), and ovariectomized + 100 mg/kg raw FC (RW100). After eight weeks of treatments, rats were euthanized and femurs were dissected out to measure bone osteocalcin, Ctelopeptide of type 1 collagen and bone estrogen level. Results: RW50 and RW100 showed an increasing trend in osteocalcin levels and also oestrogen level, but no significant difference between all groups. RW50 and RW100 also showed significantly reduced C-telopeptide of type 1 collagen levels compared to OVX group. Conclusion: These findings suggested that raw FC at the doses of 50 mg/kg and 100 mg/kg have potential to improve bone in treating post-menopausal osteoporosis. However, this need to be confirmed with higher doses.

Green tea extract rich in epigallocatechin gallate impairs alveolar bone loss in ovariectomized rats with experimental periodontal disease.

Periodontal disease and osteoporosis are characterized by bone resorption, and researchers have shown an association between these two diseases through increasing loss of systemic bone mass and triggering alveolar bone loss. Green tea is a common and easily accessible beverage, and evidences show that flavonoid epigallocatechin gallate (EGCG) could decrease bone loss in pathologies such as osteoporosis and periodontal disease. In order to verify its possible effects and apply them in the treatment and prevention of these diseases, this investigation aimed to evaluate the influence of green tea extract (GTE) on bone metabolism of ovariectomized rats after experimental periodontal disease (EPD) by histological, morphological and microtomographic parameters. Wistar female rats were divided into Sham, Sham+EPD, Sham+EPD+GTE, OVX, OVX+EPD and OVX+EPD+GTE groups. Immediately after surgery, gavage administration of 50mg/kg of green tea extract (GTE) was performed for 60days, with subsequent induction of periodontal disease by ligature 15days before euthanasia. Mandible and femur samples were collected for histological, morphometric and microtomographic analysis. The results were analysed by means of statistical software with significance set at 5%. Histological and morphometric analysis showed a significant decrease in alveolar and femoral trabecular bone loss in groups that received GTE. Microtomographic results showed that trabecular thickness and bone surface density values in alveolar bone interradicular septum of the OVX+EPD+GTE groups were similar to the Sham group. The results obtained suggest that green tea extract may improve bone metabolism in osteoporotic rats with periodontal disease.

Effect of the methanol extract of the Lion's Mane mushroom, Hericium erinaceus, on bone metabolism in ovariectomized rats

Purpose: Osteoporosis is a major health concern in postmenopausal women. The aim of the study was to investigate the effect of Hericium erinaceus (H. erinaceus), also known as the Lion’s Mane mushroom, consumption on bone metabolism in ovariectomized (Ovx) rats. Materials and Methods: Rats in the Baseline group were sacrificed immediately, whereas rats in the Sham group underwent sham surgery, and those in the Ovx and Ovx + HE groups underwent bilateral Ovx. A diet containing the methanol extract of H. erinaceus was given to the Ovx+HE group for 13 weeks. Results: There was no significant difference in the femoral bone mass between the Ovx and Ovx+HE groups. In the histomorphometric study of the proximal tibial metaphysis, the osteoblast surface, mineralizing surface, and fat cell number were lower in the Ovx+HE group than those in the Ovx group. Conclusion: The present findings suggest that H. erinaceus does not prevent but rather accelerates bone loss in Ovx rats.

Enhancement of glucose and bone metabolism in ovariectomized rats fed with germinated pigmented rice with giant embryo (Oryza sativa L. cv. Keunnunjami).

BackgroundMenopause induces various metabolic disorders due to the rapid decrease of the ovarian hormone estrogen. It is involved in increased risk of obesity, diabetes, dyslipidemia, and osteoporosis. The pigmented giant embryo cultivar is a promising food product for menopause-induced metabolic disorders.ObjectiveThe effects of non-germinated and germinated Keunnunjami, a new blackish purple pigmented rice with a giant embryo, on glucose and bone metabolisms in ovariectomized rats were investigated.DesignThe animals were fed with normal control diet (NC group) or control diet supplemented with either non-germinated Keunnunjami (KN group) or germinated Keunnunjami (GKN group) powder for 8 weeks.ResultsThe blood glucose and plasma insulin levels, adipokine concentrations, hepatic glucose-regulating enzyme activities, and bone resorption biomarker levels significantly decreased in KN and GKN groups compared to those of the control animals.DiscussionThese findings illustrate that GKN group showed greater hypoglycemic activity and lower bone resorption than KN group, suggesting that germination could further improve the physiological property of Keunnunjami.ConclusionGerminated Keunnunjami may have therapeutic potential against hyperglycemia and bone turnover imbalance caused by menopause.

Effect of esculetin on bone metabolism in ovariectomized rats

OBJECTIVETo determine the effect of an esculetin formulation (at 97.4% purity) on osteoporosis, and to investigate the potential underlying molecular mechanism(s). METHODSSixty specific pathogen free-grade female Wistar rats were randomly assigned to three groups: blank control (n = 12), sham (n = 12), and model (n = 36). The model group were bilaterally ovariectomized. The sham group had the tissue surrounding the ovaries removed, while the ovaries were retained. After 3 months, the model group was randomly divided into three subgroups: OVX (n = 12), positive control (n = 12), and esculetin (n = 12). The positive control group and the esculetin group were intragastrically administered diethylstilbestrol (0.046 mg • kg−1 • d−1) or esculetin (384 mg • kg−1 • d−1), respectively, once per day for 6 consecutive days; medication administration was then stopped for 1 d, before being administered for another 6 consecutive days. All rats were treated for 3 months. Samples were collected at the end of the treatment period. An Osteocore3 Digital 2D bone densitometer was used to test the bone mineral density, and histomorphometric analysis was performed to measure bone mass, bone formation, and bone resorption. Enzyme-linked immunosorbent assay analysis was used to measure the serum concentrations of interleukin-6 (IL-6), osteoprotegerin (OPG), and receptor activator of nuclear factor-kappa B ligand (RANKL). Immunohistochemistry and in situ hybridization were performed to detect the protein and mRNA expressions of OPG and RANKL in osteoblasts and bone marrow stromal cells. RESULTSCompared with the OVX group, the esculetin group had significantly greater femoral bone mineral density and tibial trabecular bone volume, and significantly smaller trabecular resorption surface. The percentage of trabecular formation surface, average osteoid width, trabecular bone mineralization rate, and cortical bone mineralization rate did not significantly differ between groups. Compared with the sham group, the esculetin group had significantly decreased serum levels of IL-6 and RANKL, and significant downregulation of RANKL protein and mRNA expression levels in osteoblasts and bone marrow stromal cells; however, there was no significant difference between groups in OPG. CONCLUSIONEsculetin can increase bone mass by upregulating RANKL expression in osteoblasts and bone marrow stromal cells, and decreasing serum IL-6 concentration. This indicates that the therapeutic effect of esculetin on osteoporosis occurs via decreased bone resorption.

Cynomorium songaricum prevents bone resorption in ovariectomized rats through RANKL/RANK/TRAF6 mediated suppression of PI3K/AKT and NF-κB pathways

AimCynomorium songaricum Rupr., an edible and important Traditional Chinese medicine has long been used in folk for treatment of kidney deficiency, was chosen to estimate the antiosteoporotic activity and underlying molecular mechanism on rats induced by ovariectomy (OVX). Main methods9 of 45 rats were underwent bilateral laparotomy without removing the ovaries as sham group, remains were underwent bilateral ovariectomy and equally randomized into four groups: with vehicle (0.5% CMC-Na) as model group, estradiol valerate (1 mg/kg body weight/day) as positive control, with 100 and 300 mg/kg body weight/day of ethanol extracts of C. songaricum extract (CSE) as low and high dosage groups, respectively. Key findingsAfter 12 weeks of continues orally intervention, the decreases of bone mineral density, bone mineral content, tissue mineral content, as well as the increases of bone trabecular separation and bone resorption markers were significantly reversed by CSE in the OVX rats, and in particular, a contradictory phenomenon on calcium and phosphorus contents was observed and elucidated. Mechanistically, the expressions of tumor-necrosis factor receptor-associated factor 6 (TRAF 6), nuclear factor kappa B (RANK) and its ligand (RANKL), as well as the nuclear factor kappa B (NF-κB), phosphoinositide 3‑kinase (PI3K) and protein kinase B (AKT) levels were significantly down-regulated by CSE intervention, whereas the osteoprotegerin (OPG) was significantly up-regulated by CSE as compared to the control. SignificanceConcisely, C. songaricum exhibited potential therapeutic effect on bone metabolism of ovariectomized rats, and this effect was possibly exerted by RANKL/RANK/TRAF6 mediated down-regulation of NF-κB and PI3K/AKT pathways.

Effect of Xianling Gubao capsule on bone metabolism in ovariectomized rats

To investigate the effect of Xianling Gubao capsule in preventing postmenopausal osteoporosis, forty-eight female Wistar rats were randomly divided into four groups: sham group (Sham), ovariectomized group (OVX), ethinylestradiol group (EE) and Xianling Gubao capsule group (XLGB). Rats in each group received ovariectomy, except for sham group. The XLGB group received Xianling Gubao capsule at the dose of 378 mg·kg⁻¹·d⁻¹. The dosage of EE group was 200 μg·kg⁻¹·d⁻¹, and OVX and Sham groups were only fed with equal volume of distilled water. All of the rats were put to death two months later. Bone mineral density, bone biomechanics, bone histomorphometry Micro-CT scanning and organ index of vital organs were calculated and pathologically observed. There was no significant difference in the body weight of rats and organ indexes of lung, kidney, heart and spleen in the experimental groups. There was also no significant change in their pathological observation, but the uterine index of OVX group and XLGB group was significantly lower than that of Sham group. According to the results of BMD test, compared with the OVX group, femurs and vertebrae BMD of the other three groups were increased, with statistically significant differences. On the basis of the results of bone biomechanical test, compared with OVX group, the maximum load values of femur and vertebrae of the other three groups were increased, with statistically significant differences, while the change of elastic modulus was not statistically significant. According to the bone histomorphometry results of VG staining, compared with Sham group, the number of trabecular bone was significantly lower than that in OVX group. Compared with OVX group, the number of trabecular bone in EE group and XLGB group was increased, but with no significant difference between EE and XLGB groups. The results of serum biochemical indexes showed that compared with Sham group, osteocalcin (OC) decreased, while tartrate resistant acid phosphatase 5b (TRACP 5b) increased in OVX group, with statistically significant differences. Compared with OVX group, the OC content of XLGB group and EE group increased, while the content of TRACP 5b decreased, with statistically significant differences. On the basis of the results of Micro-CT scanning, the change trends of femur volume BMD, number of trabecular bone (Tb.N), trabecular bone thickness (Tb.Th), trabecular bone separation (Tb.Sp), bone volume/tissue volume (BV/TV) in the groups were consistent with those of bone histomorphometry. There was no significant change in femoral cortical bone between the two groups. Xianling Gubao capsule can prevent osteoporosis in ovariectomized rats. The possible mechanism is the dual activity of inhibiting bone resorption and improving bone formation.

Effect of long-term administration of mangiferin from Belamcanda chinensis on bone metabolism in ovariectomized rats

Mangiferin has demonstrated in vitro inhibitory influence on RANKL (Receptor Activator of Nuclear Factor Kappa B Ligand) mediated osteoclasts activity. In this study we evaluated the effect of mangiferin on ovariectomy-induced osteopenia in rats. Animals were randomized into four groups: SHAM (“sham” operated group) and three ovariectomized groups (OVX-C – controls; OVX-M10 – mangiferin 10 mg/kg/day and OVX-M30 – mangiferin 30 mg/kg/day). Mangiferin administration began 3 months after ovariectomy and was continued for 6 consecutive months. In mangiferin-treated rats we demonstrated decrease in bCTX (beta C-terminated telopeptide of type I collagen) level and increase in BMD (bone mineral density) comparing to OVX-C. Bone histomorphometric parameters were in OVX-M10 and OVX-M30 significantly better than in OVX-C. No influence of mangiferin on OC (osteocalcin) level was detected. Thus mangiferin demonstrated antiresorptive influence on bone metabolism and it attenuated ovariectomy-induced bone changes.

Intermittent fasting protects against the deterioration of cognitive function, energy metabolism and dyslipidemia in Alzheimer's disease-induced estrogen deficient rats.

Intermittent fasting may be an effective intervention to protect against age-related metabolic disturbances, although it is still controversial. Here, we investigated the effect of intermittent fasting on the deterioration of the metabolism and cognitive functions in rats with estrogen deficiency and its mechanism was also explored. Ovariectomized rats were infused with β-amyloid (25-35; Alzheimer's disease) or β-amyloid (35-25, Non-Alzheimer's disease; normal cognitive function) into the hippocampus. Each group was randomly divided into two sub-groups: one with intermittent fasting and the other fed ad libitum: Alzheimer's disease-ad libitum, Alzheimer's disease-intermittent fasting, Non-Alzheimer's disease-ad libitum, and Non-Alzheimer's disease-intermittent fasting. Rats in the intermittent fasting groups had a restriction of food consumption to a 3-h period every day. Each group included 10 rats and all rats fed a high-fat diet for four weeks. Interestingly, Alzheimer's disease increased tail skin temperature more than Non-Alzheimer's disease and intermittent fasting prevented the increase. Alzheimer's disease reduced bone mineral density in the spine and femur compared to the Non-Alzheimer's disease, whereas bone mineral density in the hip and leg was reduced by intermittent fasting. Fat mass only in the abdomen was decreased by intermittent fasting. Intermittent fasting decreased food intake without changing energy expenditure. Alzheimer's disease increased glucose oxidation, whereas intermittent fasting elevated fat oxidation as a fuel source. Alzheimer's disease and intermittent fasting deteriorated insulin resistance in the fasting state but intermittent fasting decreased serum glucose levels after oral glucose challenge by increasing insulin secretion. Alzheimer's disease deteriorated short and spatial memory function compared to the Non-Alzheimer's disease, whereas intermittent fasting prevented memory loss in comparison to ad libitum. Unexpectedly, cortisol levels were increased by Alzheimer's disease but decreased by intermittent fasting. Intermittent fasting improved dyslipidemia and liver damage index compared to ad libitum. Alzheimer's disease lowered low-density lipoprotein cholesterol and serum triglyceride levels compared to Non-Alzheimer's disease. In conclusion, Alzheimer's disease impaired not only cognitive function but also disturbed energy, glucose, lipid, and bone metabolism in ovariectomized rats. Intermittent fasting protected against the deterioration of these metabolic parameters, but it exacerbated bone mineral density loss and insulin resistance at fasting in Alzheimer's disease-induced estrogen-deficient rats. Impact statement Intermittent fasting was evaluated for its effects on cognitive function and metabolic disturbances in a rat model of menopause and Alzheimer's disease. Intermittent fasting decreased skin temperature and fat mass, and improved glucose tolerance with decreasing food intake. Intermittent fasting also prevented memory loss: short-term and special memory loss. Therefore, intermittent fasting may prevent some of the metabolic pathologies associated with menopause and protect against age-related memory decline.

Effect of anthocyanin-rich bilberry extract on bone metabolism in ovariectomized rats.

Menopause is associated with increased oxidative stress, which serves a role, in part, in the pathogenesis of postmenopausal bone loss. Fruits and vegetables are rich in antioxidative nutrients and phytochemicals. Berries are a natural source of anthocyanins, and their intake may improve bone health. The aim of the present study was to determine the effect of an anthocyanin-rich bilberry extract (VME) on bone metabolism in an ovariectomized (Ovx) rat. Female Sprague-Dawley rats (12 weeks old) were randomly divided into the following four groups: Baseline, Sham, Ovx and Ovx+VME (n=8-12 rats per group). Rats in the Baseline group were sacrificed immediately, while those in the other groups were subjected to either sham operation (Sham) or bilateral Ovx (Ovx and Ovx+VME). Rats in the Ovx+VME group were administered VME daily at a dose of 500 mg/kg body weight. At 8 weeks after surgery, bone mass and bone histomorphometry were evaluated. The femur bone mineral density (BMD) in the Ovx group was significantly lower than that in the Sham group (P<0.01). Supplementation of VME in the Ovx rats did not result in an increase in BMD. Histomorphometric analyses revealed that Ovx resulted in decreased measures of bone volume and trabecular number and increased measures of osteoid volume, mineralizing surface and bone formation rates (all P<0.01), whereas VME had no significant effects on these parameters. The present findings indicate that VME did not alter bone metabolism in Ovx rats, suggesting that consumption of VME may not be helpful in preventing postmenopausal bone loss.

Effects of combined treatment with fermented soybean (natto) intake and exercise on bone metabolism in ovariectomized rats.

Objectives:Using ovariectomized rats, we examined the influence of combined exercise tolerance and natto intake on the bone loss inhibitory effect.Methods:We divided female Wistar rats into the following groups: Ovariectomy, Ovariectomy + Exercise, Ovariectomy + Natto Intake, Ovariectomy + Exercise + Natto Intake, and Pseudo-operative (Sham group). After conducting experiments on each group, we collected the tissues and performed morphological and molecular biological analyses.Results:In comparison with the Ovariectomy group, only in the Ovariectomy + Exercise group was there a significant bone loss inhibitory effect in the femoral cancellous bone. Although there was a tendency toward this trend seen in the Natto Intake and Exercise + Natto Intake groups, these differences were not significant. The increase in messenger RNA expression levels of alkaline phosphatase (osteoblast marker) in the bone marrow caused by ovariectomy was suppressed by individual factors, and by those in combination. However, messenger RNA expression levels of estrogen receptor alpha in the bone marrow showed a decreasing tendency with each factor, and decreased significantly with the combination, similar to the Sham group.Conclusion:This suggests that natto intake and exercise maintain bone mass by different molecular mechanisms and that these two factors do not simply act synergistically in combination to maintain bone mass.

Long-term supplementation with young coconut juice does not prevent bone loss but rather alleviates body weight gain in ovariectomized rats.

Young coconut (Cocos nucifera Linn.) juice (YCJ) has traditionally been consumed to alleviate symptoms associated with the menopause. Recently, the authors demonstrated that short-term (6-week) YCJ supplementation to ovariectomized rats resulted in increased bone mass and bone formation parameter, suggesting that YCJ consumption has a positive effect on bone metabolism and may represent an intervention to help slow the bone loss during menopause transition. The present study sought to determine how long-term (12-week) YCJ supplementation affects bone metabolism in ovariectomized rats, to investigate whether such supplementation may be helpful to in osteoporosis treatment. Ten-week-old female Wistar rats were subjected to either a sham operation (Sham) or bilateral ovariectomy (Ovx). The Ovx+YCJ group received 5X-concentrated YCJ at a dose of 15 ml/kg/day for 12 weeks. Rats in the Ovx group had significantly lower femur bone mineral density than those in the Sham group. YCJ supplementation did not significantly affect this difference. However, YCJ prevented the increase in bone area of the mid third of the femur, a site high in cortical bone, and body weight gain observed following Ovx. Our findings indicate that long-term YCJ intake does not alter bone loss, but rather alleviates body weight gain following menopause.

Effects of fluoride on insulin signaling and bone metabolism in ovariectomized rats

Fluoride is an essential trace element for the maintenance of bone health owing to its capacity to stimulate proliferation and osteoblastic activity that can lead to increased bone formation. However, excessive sodium fluoride (NaF) intake can impair carbohydrate metabolism thereby promoting hyperglycemia, insulin resistance, and changes in insulin signaling. Thus, this study aimed to evaluate the effect of chronic treatment with NaF in bone metabolism, insulin signaling, and plasma concentrations of glucose, insulin, tumor necrosis factor-α (TNF-α), osteocalcin (OCN), and fluoride in ovariectomized rats. Thirty-two ovariectomized Wistar rats were randomly distributed into two groups: Control (OVX-C) and those undergoing treatment with NaF (50mg F/L) in drinking water for 42days (OVX-F). Glucose and insulin levels were assessed, followed by homeostasis model assessment of insulin resistance (HOMA-IR). Akt serine phosphorylation was evaluated by western blotting. Plasma concentrations of TNF-α and OCN were evaluated by ELISA. The left and right tibia was collected for immunohistochemical and histomorphometric analysis, respectively. Chronic treatment with NaF promoted insulin resistance, decreased insulin signal, increased plasma concentration of insulin, fluoride, OCN and TNF-α, decreased trabecular bone area of the tibia, and caused changes in bone metabolism markers in ovariectomized rats. These results suggest the need for caution in the use of NaF for the treatment of osteoporosis, especially in postmenopausal woman.

The effects of Cudrania tricuspidata extract on bone metabolism in ovariectomized rats

The effects of Cudrania tricuspidata extract on bone metabolism in ovariectomized rats

Chenopodium ambrosioides L. extract prevents bone loss.

To evaluate the effect of the Chenopodium ambrosioides L (mastruz) extract for preventing bone loss and bone metabolism in ovariectomized rats. Twelve rats were subjected to bilateral ovariectomy for inducing osteoporosis. After surgery, they were divided into two groups: Ovariectomy-control group (G1, n=6), receiving 0.5 ml distilled water by gavage for 30 days, and Ovariectomy plus mastruz group (G2, n=6), receiving 0.5 ml of the hydroalcoholic extract of mastruz at 10% concentration (50mg) daily, for the same period. Then, the blood of the animals was collected for further biochemical analysis (liver function) and tibia and liver were removed for histological and histomorphometric analyses. The cortical bone was significantly larger in the G2 than G1, whereas G1 presented the highest amount of adipocytes in the bone marrow (p<0.05). The blood levels of aspartate aminotransferase, triglycerides and cholesterol were significantly higher, whereas globulin and lactate dehydrogenase were smaller in G2 than G1. The hydroalcoholic extract of mastruz has effects on bone metabolism by changing blood proteins and enzymes and preventing both bone loss and the substitution of bone marrow cells by.