Effects In OVX Rats Research Articles

Water Extract of Rhizoma Drynaria Selectively Exerts Estrogenic Activities in Ovariectomized Rats and Estrogen Receptor-Positive Cells.

Our previous study demonstrated that the bone protective actions of herbal medicine Rhizoma Drynariae (Gusuibu, RD) were mainly mediated by flavonoid phytoestrogens via estrogen receptors, raising concerns about the safety of using RD as it may induce estrogen-like risk-benefit profile and interact with other ER ligands, such as selective estrogen receptor modulators (SERMs), when coadministered. The present study evaluated the estrogenic activities of RD and its potential interaction with tamoxifen, a SERM, in estrogen-sensitive tissues by using mature ovariectomized (OVX) rats and ER-positive cells. Similar to but weaker than tamoxifen, RD at its clinical dose dramatically ameliorated OVX-induced changes in bone and dopamine metabolism-related markers in OVX rats. However, tamoxifen, but not RD, induced uterotrophic effects. No significant alteration in mammary gland was observed in OVX rats treated with RD, which was different from the inhibitory actions of tamoxifen. The two-way ANOVA results indicated the interactions between RD and tamoxifen in the bone, brain, and uterus of OVX rats while RD did not alter their responses to tamoxifen. Our results demonstrate that RD selectively exerts estrogenic actions in a different manner from tamoxifen. Moreover, RD interacts with tamoxifen without altering its effects in OVX rats.

Protective effect of aqueous extracts from Taxillus chinensis (DC.) Danser on ovariectomy-induced osteoporosis in rats

As one of classic Chinese kidney-tonifying herbal medicines, Taxillus chinensis (DC.) Danser is widely applied in Chinese folk medicine as herbal tea for nutraceutical purposes including nourishing kidney, strengthening muscle and bone to against weakness, etc. In the present study, we investigated the protective effect of aqueous extracts from Taxillus chinensis (AETCs) on the ovariectomy (OVX)-induced osteoporosis in rats. Results showed that AETC treatment at the dose of 12.0 g raw materials/kg for 12 weeks significantly enhanced the bone mineral densities of femur and tibia, improved the trabecular microarchitecture compared with OVX controls. The serum levels of osteogenic markers alkaline phosphatase and osteocalcin were increased, and the levels of bone resorption biomarkers tartrate-resistant acid phosphatase 5b and telopeptides of collagen type I were suppressed by AETCs. Moreover, 12.0 g raw materials/kg AETC treatment significantly reduced the OVX-induced up-regulation of cyclooxygenase (COX)-2 mRNA and protein expression in bone tissues. Data suggested that AETCs showed anti-osteoporotic effect in OVX rats, possibly via promoting bone formation and inhibiting bone absorption. The down-regulation of inflammatory COX-2 might be involved in the protection of AETCs against OVX –induced osteoporosis.

Lipoic acid (LA) dose-dependently protects bone losses in the mandible of rats during the development of osteopenia by inhibiting oxidative stress and promoting bone formation

Our study was carried out to evaluate the effect of lipoic acid (LA) on the densitometric properties, structure and mechanical strength of the mandible of Wistar rats with developing osteopenia. The study used 42 sham-operated (SHO) and ovariectomized (OVX) rats. The OVX rats were randomly divided (n = 6) onto two controls treated subcutaneously with physiological saline (OVX-PhS) and 17β-estradiol (OVX-E2), respectively, and onto four experimental OVX groups that received LA in the doses of 12.5, 25, 50 and 100 mg/kg/day for 28 days. The results demonstrated that the lack of estrogen brought about osteopenic bone changes, especially in the trabecular compartment. In addition, while the usage of LA in the doses of 12.5 and 25 LA had no effect in OVX rats, the dose of 100 effectively inhibited osteopenic changes of the mandible. This dose maintained structural, densitometric and mechanical parameters at levels like that in the SHO and OVX-E2 groups by inhibiting the destructive influence of oxidative stress. Dose 50, however, was revealed to be the most effective. It not only inhibited atrophic changes and the influence of oxidative stress, but also stimulated the formation of mandibular bone tissue. Our results suggest that the administration of LA is effective in preventing atrophic changes in the mandibular bone tissue in conditions of ovarian hormone deficiency and suggest its potential in the therapy of osteoporosis.

Puerarin improves the bone micro-environment to inhibit OVX-induced osteoporosis via modulating SCFAs released by the gut microbiota and repairing intestinal mucosal integrity

ScopeHalf of women over the age of 50 will experience a fracture related osteoporosis in their lifetime. The common treatment is estrogen replacement therapy, which can cause many side effects. Puerarin as a phytoestrogen has been proven to improve postmenopausal osteoporosis. However, the mechanisms of anti-osteoporosis remain unclear due to its low bioavailability. The aim of this study is to investigate whether the anti-osteoporosis effects of puerarin are related to modulations in the gut microbiota and focus on the mechanism of gut / bone axis. MethodsWe established ovariectomized (OVX) rats as osteoporosis model. The femur was analyzed by microcomputed tomography (μ-CT) and we measured serum biochemical indices and inflammatory factors. 16S rRNA sequencing was employed to evaluate the gut microbiota composition in the fecal samples. Short-chain fatty acids (SCFAs) was analyzed by GC. The expression of intestinal inflammatory factors and adhesion proteins was confirmed by western blotting and qPCR. ResultsPuerarin increased the BMD and improved the intestinal mucosal integrity to reduce the systemic inflammation. The disorder of gut microbiota was improved and its metabolites SCFAs were elevated. Metabolic pathways such as amino acid metabolism, LPS biosynthesis and butyrate metabolism were enriched. ConclusionPuerarin treatment modulated the gut microbiota disorder to elicit the anti-osteoporosis effects in OVX rats, by improving the bone micro-environment via regulating the SCFAs levels and repairing the intestinal mucosal integrity.

A standardized extract of Danggui Buxue Tang decoction selectively exerts estrogenic activities distinctly from tamoxifen.

More and more menopausal women use Danggui Buxue Tang (DBT) for relieving their symptoms. Concerns for its safety have been raised as it contains phytoestrogen and acts via estrogen receptors (ERs). Our study aimed to determine whether DBT could selectively exert estrogenic activities and interact with tamoxifen in bone, brain, uterus, and breast by using ovariectomized (OVX) rats and ER-positive cells. In OVX rats, DBT induced a 31.4% increase in bone mineral density and restored the mRNA expression of dopamine biomarker in striatum, 3.32-fold for tyrosine hydrolase (p < .001) and 0.21-fold for dopamine transporter (p < .001), which was similar to tamoxifen; tamoxifen, but not DBT, increased uterus weight and Complement component 3 expression by more than twofold (p < .001); unlike tamoxifen, DBT induced mild proliferation in mammary gland. Two-way ANOVA indicated the interactions between them in OVX rats (p < .05) but DBT did not alter the responses to tamoxifen. DBT stimulated proliferation or differentiation and estrogen response element in MCF-7, MG-63, Ishikawa, and SHSY5Y cells and altered the effects of tamoxifen. In summary, DBT exerted estrogenic effects in tissue-selective manner, which was different from tamoxifen. DBT interacted with tamoxifen but did not significantly alter its effects in OVX rats.

Effects of soy isoflavones extract on the lipid profile and uterus in ovariectomized rats

Aim Although soy isoflavones (ISO) have been shown to relief postmenopausal symptoms, it remains inconclusive whether ISO can improve lipid-profile without uterotrophic effects under estrogen-deficiency. Thus, we investigated the effects of ISO on lipid-profile and uterus of ovariectomized (Ovx) rats. Materials and methods Twenty-five adult rats were Ovx or Sham-operated (Sham) and assigned into five groups: Sham and Ovx groups, administered with vehicle solutions; Ovx-E, treated with 10 µg/kg of 17β-Estradiol; Ovx-ISO, treated with 200 mg/kg of ISO; Ovx-E + ISO, treated with estradiol + ISO combined. After fifty days of treatments, rats were euthanized and uterine horns were processed for histomorphometry or to collagen fibers and glycosaminoglycans evaluations. Blood samples were collected to evaluate levels of triglycerides, total cholesterol (TC) and its fractions (HDL/VLDL). Data were subjected to statistical analysis (p < .05). Results Uterus weight was lower in Ovx group than the Sham and Ovx-E groups, whereas it was similar between Ovx and Ovx-ISO groups. Histomorphometry showed atrophic uterus in Ovx and Ovx-ISO groups, whereas uterotrophic effects were noticed in Ovx-E and Ovx-E + ISO groups. Collagen fibers-birefringence was higher in Sham, Ovx, and Ovx-ISO groups than in Ovx-E and Ovx-E + ISO groups. Sulfated glycosaminoglycans content was similar among Sham, Ovx, and Ovx-ISO groups, while it was higher in estrogen-treated groups; total glycosaminoglycans content was similar among groups. TC and HDL was higher in Ovx-ISO group, whereas VLDL and triglycerides levels was higher in Ovx-E + ISO group and similar among other groups. Conclusion Soy isoflavones at 200 mg/kg have slight beneficial effects on lipid-profile without uterotrophic effects in Ovx rats.

Neuroprotective effects of vitamin D and 17ß-estradiol against ovariectomy-induced neuroinflammation and depressive-like state: Role of the AMPK/NF-κB pathway

Estrogen replacement therapy (ERT) has been proven to relieve menopausal-related mental disorders including depression in postmenopausal women. However, the unsafety of ERT hinders its clinical use. In this study, we would evaluate whether vitamin D (VD), a hormone with optimal safety profile, could relieve the depressive-like symptom in ovariectomized (OVX) rats. Furthermore, we would determine whether vitamin D and 17β-estradiol (E2) exert neurological function through their immunomodulatory effect in OVX rats. Middle-aged female SD rats were randomly divided into four groups, namely, control (SHAM), OVX, OVX + VD, and OVX + E2. Vitamin D (calcitriol, 100 ng/kg) and 17β-estradiol (30 μg/kg) had been daily gavaged in the OVX + VD and OVX + E2 group, respectively. After 10-week administration, vitamin D and 17β-estradiol both showed anti-depressive-like activity in the OVX rats. Using the method of immunofluorescent staining and western blot, vitamin D and 17β-estradiol were demonstrated to upregulate each other's receptors, including VDR, ERα, and ERβ in the hippocampus of OVX rats. Additionally, the upregulation of VDR, calbindin-D28k, and calbindin-D9k suggested that the vitamin D signaling system was amplified by vitamin D and 17β-estradiol. Vitamin D and 17β-estradiol showed neuroprotective effects by decreasing OVX-induced apoptosis and neuronal damage, regulating the AMPK/NF-κB signaling pathway, and reducing the proinflammatory cytokines (IL-1β, IL-6, and TNFα), as well as iNOS and COX-2 in the hippocampus of OVX rats. Collectively, the present study demonstrated that vitamin D and 17β-estradiol could upregulate each other's receptors and regulate the AMPK/NF-κB pathway to relieve the OVX-induced depressive-like state. The results could stimulate translational research towards the vitamin D potential for prevention or treatment of menopause-related depression.

Protective Effect of Oxytocin Against Bone Loss in a Female Rat Model of Osteoporosis

Introduction: Oxytocin (OT) has been proposed to assist in the regulation of bone remodeling and to exert an antiosteoporotic effect. We evaluated the possible protective effect of OT against bone degeneration in ovariectomized (OVX) rats. The study was performed on three groups of adult female rats; group I was subjected to sham operation, group II was subjected to ovariectomy, and group III was subjected to ovariectomy and intraperitoneal injection with OT for eight successive weeks. At the end of the study, bone mass density (BMD) was measured; then the rats were euthanized and their blood and bone tissues were examined. The group II rats had significantly less BMD and greater serum bone-specific alkaline phosphatase (bALP), osteocalcin (OC), and tartrate-resistant acid phosphatase (TRAP) levels than the group I rats. Furthermore, group II rats had fewer osteocytes and osteoblasts, and less OPG/RANKL mRNA expression than group I rats. The groups I and III and rats showed no significant differences in BMD, bALP, OC, TRAP, OPG/RANKL mRNA expression, or osteocyte and osteoblast numbers. Oxytocin may have an antiosteoporotic effect in OVX rats.

Estradiol Potentiates But Is Not Essential for Prolactin-Induced Suppression of Luteinizing Hormone Pulses in Female Rats.

Hyperprolactinemia causes infertility by suppressing gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion. Because effects of prolactin (PRL) on the hypothalamus usually require estradiol (E2), we investigated the role of E2 in PRL-induced suppression of LH pulses. Ovariectomized (OVX) rats treated with oil or E2 (OVX + E2) received a subcutaneous injection of ovine PRL (oPRL) 30 minutes before serial measurement of LH in the tail blood by enzyme-linked immunosorbent assay. E2 reduced pulsatile LH secretion. oPRL at 1.5 mg/kg further reduced LH pulse frequency in OVX + E2 but had no effect in OVX rats. The higher dose of 6-mg/kg oPRL decreased LH pulse frequency in both OVX and OVX + E2 rats, whereas pulse amplitude and mean LH levels were lowered only in OVX + E2 rats. Kisspeptin immunoreactivity and Kiss1 messenger ribonucleic acid (mRNA) levels were decreased in the arcuate nucleus (ARC) of OVX + E2 rats. oPRL decreased both kisspeptin peptide and gene expression in the ARC of OVX rats but did not alter the already low levels in OVX + E2 rats. In the anteroventral periventricular nucleus, oPRL did not change kisspeptin immunoreactivity and, paradoxically, increased Kiss1 mRNA only in OVX + E2 rats. Moreover, oPRL effectively reduced Gnrh expression regardless of E2 treatment. In this study we used tail-tip blood sampling to determine the acute effect of PRL on LH pulsatility in female rats. Our findings characterize the role of E2 in the PRL modulation of hypothalamic components of the gonadal axis and LH release, demonstrating that E2 potentiates but is not essential for the suppression of pulsatile LH secretion caused by hyperprolactinemia.

Estrogen modulation of pain perception with a novel 17\u03b2-estradiol pretreatment regime in ovariectomized rats

Estrogen plays substantial roles in pain modulation; however, studies concerning sex hormones and nociception often yield confusing results. The discrepancy could be a result of lack of consensus to regard estrogen as a variable when working with animal models; thus, the influence of hormones’ fluctuations on nociception has continually been neglected. In the present study, we designed a novel hormone substitution model to aid us to evaluate the effects of estrogen’s long-term alterations on ovariectomy (OVX)-induced mechanical hyperalgesia and the expression of estrogen receptors(ERs). OVX rats were implanted with slow-release estrogen pellets at differently arranged time points and doses, such that a gradual elevation or decrease of serum estrogen levels following a relatively stable period of estrogen replacement was achieved in rats. Our results demonstrated that gradual estrogen depletion rather than elevation following the stable period of estrogen substitution in OVX rats alleviated OVX-induced mechanical hyperalgesia in a dose-independent manner, and the opposite estrogen increase or decrease paradigms differently regulate the expression of spinal ERs. Specifically, in rats rendered to continuously increased serum estrogen, the early phase estrogen-induced anti-nociception effect in OVX rats was eliminated, which was accompanied by an over-activation of ERα and a strong depression of ERβ, while in the OVX rats subject to gradual decrease of estrogen replacement, both ERα and ERβ increased modestly compared with the OVX group. Thus, the present study demonstrated that estrogen increase or decrease modulate nociception differently through change of spinal ERs.

ERK activation by zeranol has neuroprotective effect in cerebral ischemia reperfusion

AimsIncidence of stroke increases in postmenopausal women with dangerous consequences. In this study we used zeranol to protect ovariectomized (OVX) rats against cerebral I/R damage and our target is to identify the mechanism of its protection, in addition to investigating whether this mechanism inhibits inflammation (by preventing glial cell activation) and apoptosis. Main methodsFirst 18 ovariectomized rats were allocated into 3 groups: I/R group, zeranol+ I/R group and U0126, MEK1/2 inhibitor + zeranol+ I/R group. After 24 h reperfusion, protein expression of total extracellular signal-regulated protein kinase (t-ERK1/2), phosphorylated extracellular signal-regulated protein kinase (p-ERK1/2), Bcl-2, and Bax were quantified.Second 36 female rats were allocated into 3 groups: sham group, I/R group (after ovariectomy by 7 weeks, rats exposed to cerebral I/R) and zeranol group (after ovariectomy by 2 weeks, rats received zeranol for 5 weeks). After 24 h of reperfusion, the following parameters were measured; total nitrate/nitrite, interleukin-10, myeloperoxidase, caspase-3, and finally immunohistochemistry analysis of glial fibrillary acidic protein, cyclooxygenase-2 in cortex and hippocampus (CA1) regions were performed. Key findingsU-0126 administration reversed the neuroprotective effect induced by zeranol through decreasing ratio of p-ERK1/2:ERK1/2 and Bcl-2/Bax in brain tissue.Activation of ERK signaling pathway by zeranol caused reduction in brain apoptosis and inflammation. SignificanceZeranol showed protective effect in OVX rats that were exposed to cerebral I/R by activation of ERK signaling pathway which was blocked by U0126. This protective effect in turns led to decrease inflammation and apoptosis.

N-acetylcysteine and alpha-lipoic acid improve antioxidant defenses and decrease oxidative stress, inflammation and serum lipid levels in ovariectomized rats via estrogen-independent mechanisms

Sexual hormone deficiency has been associated with metabolic changes, oxidative stress and subclinical inflammation in postmenopausal women. Hormone replacement therapies are effective in many instances, even though some patients either do not respond or are not eligible. The aim of this study was to evaluate the impact of short- (15 days) versus long-term (60 days) sexual hormone depletion and whether antioxidant supplementation with N-acetylcysteine (NAC) and alpha-lipoic acid (LA) improves oxidative stress, metabolic, and inflammatory parameters in ovariectomized (OVX) rats. Short-term OVX rapidly depleted circulating estrogen, causing uterine atrophy and body weight gain without affecting oxidative damage, inflammatory and lipid metabolism markers. In contrast, long-term OVX augmented oxidative damage in serum and peripheral tissues as well as increased serum total cholesterol, TNF-α and IL6 levels. Triglycerides, glucose and HDL cholesterol were not altered. Long-term OVX-induced oxidative stress was associated with depletion of GSH and total non-enzymatic antioxidants as well as decreased activity of Glutathione Peroxidase (GPx) and Glutathione Reductase (GR), but not Superoxide Dismutase (SOD) and Catalase (CAT). NAC and LA supplementation prevented GSH and total non-enzymatic antioxidants depletion as well as restored GPx and GR activities, TNF-α, IL6 and cholesterol in OVX rats. NAC and LA effects appear to be independent on NRF2 activation and estrogen-like activity, since NAC/LA did not promote NRF2 activation and were not able to emulate estrogen effects in OVX rats and estrogen-receptor-positive cells. The herein presented data suggest that NAC and LA may improve some deleterious effects of sexual hormone depletion via estrogen-independent mechanisms.

A Metabolomics Study on the Bone Protective Effects of a Lignan-Rich Fraction From Sambucus Williamsii Ramulus in Aged Rats.

The lignan-rich fraction (SWR) of Sambucus Williamsii Ramulus, a folk herbal medicine in China for treatment of bone diseases, has previously reported to exert protective effects on bone without exerting uterotrophic effects in ovariectomized (OVX) mice. The aim of the present study was to identify the potential metabolites and the associated metabolic pathways that contribute to the beneficial effects of SWR on bone in vivo. Aged female Sprague Dawley rats (9 months old) were either sham-operated or ovariectomized for 12 weeks, before receiving treatment for another 12 weeks with the following treatment groups (n = 12 each): vehicle (Sham), vehicle (OVX), Premarin (130 μg/kg) or low (57 mg/kg), medium (114 mg/kg), and high (228 mg/kg) doses of SWR. The results showed that SWRH significantly suppressed bone loss, improved bone micro-architecture and increased bone strength on tibia without stimulating uterus weight gain in OVX rats. Premarin exerted similar bone protective effects as SWRH but elicited uterotrophic effects in OVX rats. The metabolic profiles of serum samples were analyzed by using ultra-performance liquid chromatography quadrupole time-of flight mass spectrometry and gas chromatography time-of flight mass spectrometry, and the metabolites that were significantly altered were identified by multivariate statistical analysis. Our study indicated that SWRH effectively restored the changes of 26 metabolites induced by estrogen-deficiency in OVX rats, which related to lipids, amino acids, tryptophan metabolisms, and anti-oxidative system. A subsequent validation showed that the serum level of superoxide dismutase and catalase were indeed up-regulated, while the serotonin level in a tryptophan hydroxylase 1 (TPH1) high expressing cells (rats RBL-2H3 cells) was down regulated after treatment with SWR. The results also suggested that the gut-microbiota may play an important role on the bone protective effects of SWR. The current study provides insight for understanding the unique mechanism of actions of SWR that might be involved in achieving bone protective effects in vivo.

Abaloparatide Exerts Bone Anabolic Effects with Less Stimulation of Bone Resorption-Related Factors: A Comparison with Teriparatide

Abaloparatide (ABL) is a novel synthetic peptide analog of parathyroid hormone-related protein. In previous reports, intermittent ABL administration showed robust bone mineral density (BMD) increase and reduced the incidence of fractures in patients with osteoporosis, while its calcemic effect was reduced, as compared with teriparatide (TPTD), a parathyroid hormone N-terminal fragment. The present study aimed to elucidate the effects of ABL on bone anabolism and bone turnover as compared with TPTD. In ovariectomized (OVX) rats, ABL increased the bone strength and BMD of lumbar spine by intermittent administration similar to TPTD. Both ABL and TPTD increased the bone formation marker serum P1NP with little effect on the bone resorption maker urine DPD/Cr, suggesting anabolic effects on bone. In human osteoblastic cells, both peptides increased the expression of bone resorption-related factors such as RANKL/OPG and M-CSF, and the effects of ABL were significantly attenuated as compared with those of TPTD under transient 6-h treatment, although no significant differences were found under continuous treatment. In contrast, ABL and TPTD similarly promoted the expression of bone formation-related factors, IGF-1 and osteocalcin. In addition, there were no significant differences in the effects on WNT signaling inhibitors such as sclerostin and dickkopf-related protein 1 (DKK1) between the two peptides. These results demonstrate that ABL exerts bone anabolic effects in OVX rats. It is also indicated that ABL stimulates the expression of RANKL/OPG and M-CSF less than TPTD, while showing similar effects on bone formation-related factors and WNT signaling inhibitors in vitro. The profile of ABL indicates that it would be a suitable bone anabolic agent for osteoporosis.

An estradiol-independent BDNF-NPY cascade is involved in the antidepressant effect of mechanical acupuncture instruments in ovariectomized rats

Menopause-related depression devastates women’s quality of life after middle age. Previous research has shown that estrogen hormone therapy has serious adverse effects; thus, complementary and integrative therapies have been considered clinically. The present study investigates whether stimulation of an acupoint using a mechanical acupuncture instrument (MAI) can mitigate depression-like behavior caused by estrogen deficiency in ovariectomized (OVX) rats. The animals were divided into Sham OVX, OVX, OVX + Sameumgyo (SP6) and OVX + NonAcu (non-acupuncture point) groups. MAI stimulation significantly increased the total distance traveled in the open-field test and the number of open-arm entries in the elevated plus maze and decreased the duration of immobility in the forced swim test. In addition to this decrease in depression-like behavior, brain-derived neurotrophic factor (BDNF) and neuropeptide Y (NPY) release increased in the hippocampus in response to MAI treatment, but estradiol levels did not recover. Furthermore, microinjection of the BDNF receptor antagonist ANA-12 (0.1 pmol/1 μl) into the hippocampus before MAI stimulation significantly suppressed the recovery of NPY levels. Taken together, these findings indicate that MAI stimulation at SP6 facilitates an estradiol-independent BDNF-NPY cascade, which may contribute to its antidepressant effects in OVX rats, an animal model of menopausal disorders.

Morinda citrifolia L. Leaf Extract Protects against Cerebral Ischemia and Osteoporosis in an In Vivo Experimental Model of Menopause.

We aimed to determine the protective effects against cerebral ischemia and osteoporosis of Morinda citrifolia extract in experimental menopause. The neuroprotective effect was assessed by giving M. citrifolia leaf extract at doses of 2, 10, and 50 mg/kg BW to the bilateral ovariectomized (OVX) rats for 7 days. Then, they were occluded in the right middle cerebral artery (MCAO) for 90 minutes. The neurological score, brain infarction volume, oxidative stress status, and ERK1/2 and eNOS activities were assessed 24 hours later. M. citrifolia improved neurological score, brain infarction, and brain oxidative stress status in the cortex of OVX rats plus the MCAO. No changes in ERK 1/2 signal pathway and NOS expression were observed in this area. Our data suggested that the neuroprotective effect of the extract might occur partly via the improvement of oxidative stress status in the cortex. The antiosteoporotic effect in OVX rats was also assessed after an 84-day intervention of M. citrifolia. The serum levels of calcium, osteocalcin, and alkaline phosphatase and osteoblast density in the tibia were increased, but the density of osteoclast was decreased in OVX rats which received the extract. Therefore, the current data suggested that the extract possessed antiosteoporotic effect by increasing bone formation but decreasing bone resorption.

آثار مكملات فيتامين ب المركب وحدها أو مجتمعة مع الإستروجين على فقدان العظام في الفئران المبيضة

آثار تناول فيتامين بي المركب وحده أوجنباً الي جنب مع الإستروجين على فقدان العظام في الجرذان المستأصلة المبايض. خلفية البحث: أصبحت هشاشة العظام بعد انقطاع الطمث قضية صحية عالمية في الآونة الأخيرة. تلعب العديد من الفيتامينات دورا في بناء وصيانة العظام.الهدف من البحث: تهدف هذه الدراسة الي تقييم الأدوار الممكنة لتناول فيتامين ب المركب وحده أوجنباً الي جنب مع الإستروجين في تحسين هشاشة العظام في الجرذان المستأصلة المبايض. مواد و طرق البحث: تم تقسيم 50 من إناث الجرذان البيضاء البالغة إلي خمس مجموعات متساوية ثم تعرضت أربع مجموعات منها لإستأصال المبايض: الأولى ضابطة, والثانية مستأصلة المبايض والثالثة مستأصلة المبايض و أعطيت إثينيل استراديول والرابعة مستأصلة المبايض و أعطيت فيتامين بي المركب والخامسة مستأصلة المبايض و أعطيت إثينيل استراديول وفيتامين بي المركب. بدأت جميع العلاجات بعد أربعة أسابيع من الجراحة واستمرت لمدة ثمانية أسابيع. تم جمع عينات الدم لقياس مستويات الهوموسيستايين و الفوسفاتاز القلوي العظمي وكاربوكسي الببتيد الرابط للنوع الأول من الكولاجين والكالسيوم فى مصل الدم. نتائج البحث:زاد استأصال المبايض من مستويات الهوموسيستايين ودلالات تقلب العظام (الفوسفاتاز القلوي العظمي و وكاربوكسي الببتيد الرابط للنوع الأول من الكولاجين) و الكالسيوم فى مصل الدم. إرتفعت مستويات الكالسيوم ، في حين انخفضت مستويات علامات تقلب العظام و الهوموسيستايين في جميع المجموعات التي تلقت علاجاً و لكن فقط علاج الجرذان بفيتامين ب المركب جنباً الي جنب مع الإستروجين أعاد مستويات الهوموسيستايين ووكاربوكسي الببتيد الرابط للنوع الأول من الكولاجين إلى وضعها الطبيعي. الإستنتاج: أظهر فيتامين ب المركب بعض التأثيرات المضادة لهشاشة العظام في الجرذان المستأصلة المبايض.

Effects of Chronic Vitamin D₃ Hormone Administration on Anxiety-Like Behavior in Adult Female Rats after Long-Term Ovariectomy.

The present preclinical study was created to determine the therapeutic effects of vitamin D hormone treatment as an adjunctive therapy alone or in a combination with low dose of 17β-estradiol (17β-E2) on anxiety-like behavior in female rats with long-term absence of estrogen. Accordingly, the aim of the current study was to examine the effects of chronic cholecalciferol administration (1.0, 2.5 or 5.0 mg/kg subcutaneously, SC, once daily, for 14 days) on the anxiety-like state after long-term ovariectomy in female rats. Twelve weeks postovariectomy, cholecalciferol was administered to ovariectomized (OVX) rats and OVX rats treated with 17β-E2 (0.5 µg/rat SC, once daily, for 14 days). Anxiety-like behavior was assessed in the elevated plus maze (EPM) and the light/dark test (LDT), and locomotor and grooming activities were tested in the open field test (OFT). Cholecalciferol at two doses of 1.0 and 2.5 mg/kg alone or in combination with 17β-E2 produced anxiolytic-like effects in OVX rats as evidenced in the EPM and the LDT, as well as increased grooming activity in the OFT. Our results indicate that cholecalciferol, at two doses of 1.0 and 2.5 mg/kg, has a profound anxiolytic-like effects in the experimental rat model of long-term estrogen deficiency.

Cardioprotective effects of vitamin B complex and Ethinyl Estradiol in ovariectomized rats

Background/aim Reduction of female sex hormones is associated with health disorders including cardiovascular diseases such as hypertension. Supplementation with vitamin B complex can lower the incidence of these disorders. The present study aimed to study the potential cardioprotective effects of vitamin B complex and ethinyl estradiol (EE) when administered alone or in combination to hormonal-deprived ovariectomized (OVX) rats. Materials and methods Fifty female Wister rats were classified into five equal groups: the first group included normal rats, the second group was OVX (positive control), and the third to fifth groups were OVX rats that were treated by EE (0.03 mg/kg), vitamin B complex (9.036 mg/kg), and a combination of both treatments, respectively. Treatment continued for eight successive weeks. Blood pressure (BP), cystathionine γ-lyase (CSE), reduced glutathione (R-GSH), superoxide dismutase (SOD), catalase (CAT), and interleukin-β6 (IL-β6) were measured. Results The OVX rats showed a significant increase in BP, reduction in CSE, R-GSH, SOD, and CAT, and increase in IL-β6 levels, whereas the treated OVX rats showed a significant decrease in BP, increase in CSE, R-GSH, SOD, and CAT, and reduction in IL-β6 levels. Conclusion Vitamin B complex and EE exert cardioprotective effects in OVX rats.

Estrogen Receptors α and β Play Major Roles in Ethanol-Evoked Myocardial Oxidative Stress and Dysfunction in Conscious Ovariectomized Rats.

We documented the dependence of ethanol (EtOH)-evoked myocardial dysfunction on estrogen (E2 ), and our recent estrogen receptor (ER) blockade study, in proestrus rats, implicated ERα signaling in this phenomenon. However, a limitation of selective pharmacological loss-of-function approach is the potential contribution of the other 2 ERs to the observed effects because crosstalk exists between the 3 ERs. Here, we adopted a "regain"-of-function approach (using selective ER subtype agonists) to identify the ER subtype(s) required for unraveling the E2 -dependent myocardial oxidative stress/dysfunction caused by EtOH in conscious ovariectomized (OVX) rats. OVX rats received a selective ERα (PPT), ERβ (DPN), or GPER (G1) agonist (10μg/kg; i.v.) or vehicle 30minutes before EtOH (1.0g/kg; infused i.v. over 30minutes) or saline, and the hemodynamic recording continued for additional 60minutes. Thereafter, left ventricular tissue was collected for conducting exvivo molecular/biochemical studies. EtOH had no hemodynamic effects in OVX rats, but reduced the left ventricular contractility index, dP/dtmax , and MAP after acute ERα (PPT) or ERβ (DPN) activation. These responses were associated with increases in the phosphorylation of ERK1/2 and eNOS, and in reactive oxygen species (ROS) and malondialdehyde (MDA) levels in the myocardium. GPER activation (G1) only unraveled a modest EtOH-evoked hypotension and elevation in myocardial ROS. PPT enhanced catalase, DPN reduced ALDH2, while G1 had no effect on the activity of either enzyme, and none of the agonists influenced alcohol dehydrogenase or CYP2E1 activities in the myocardium. Blood EtOH concentration (96.0mg/dl) was significantly reduced following ERα (59.8mg/dl) or ERβ (62.9mg/dl), but not GPER (100.3mg/dl), activation in EtOH-treated OVX rats. ERα and ERβ play major roles in the E2 -dependent myocardial dysfunction caused by EtOH by promoting combined accumulation of cardiotoxic (ROS and MDA) and cardiodepressant (NOS-derived NO) molecules in female myocardium.