Systematic review and meta-analysis of the bone protective effect of phytoestrogens on osteoporosis in ovariectomized rats

Molecular mechanisms of poor osseointegration in irradiated bone: In vivo study in a rat tibia model

AIM

Radiotherapy is associated with cell depletion and loss of blood supply, which are linked to compromised bone healing. However, the molecular events underlying these effects at the tissue-implant interface have not been fully elucidated. This study aimed to determine the major molecular mediators associated with compromised osseointegration due to previous exposure to radiation.

MATERIALS AND METHODS

Titanium implants were placed in rat tibiae with or without pre-exposure to 20 Gy irradiation. Histomorphometric, biomechanical, quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay analyses were performed at 1 and 4 weeks after implantation.

RESULTS

The detrimental effects of irradiation were characterized by reduced bone-implant contact and removal torque. Furthermore, pre-exposure to radiation induced different molecular dysfunctions such as (i) increased expression of pro-inflammatory (Tnf) and osteoclastic (Ctsk) genes and decreased expression of the bone formation (Alpl) gene in implant-adherent cells; (ii) increased expression of bone formation (Alpl and Bglap) genes in peri-implant bone; and (iii) increased expression of pro-inflammatory (Tnf) and pro-fibrotic (Tgfb1) genes in peri-implant soft tissue. The serum levels of pro-inflammatory, bone formation and bone resorption proteins were greater in the irradiated rats.

CONCLUSIONS

Irradiation causes the dysregulation of multiple biological activities, among which perturbed inflammation seems to play a common role in hindering osseointegration.

Anti-osteoporotic effects of Boswellia serrata gum resin extract in vitro and in vivo

BACKGROUND/OBJECTIVES

This study evaluated the beneficial effects of an ethanol extract of Boswellia serrata gum resin (FJH-UBS) in osteoporosis.

MATERIALS/METHODS

MC3T3-E1 osteoblastic cells and RAW 264.7 osteoclastic cells were treated with FJH-UBS. The alkaline phosphatase (ALP) activity, mineralization, collagen synthesis, osteocalcin content, and Runt-related transcription factor 2 (RUNX2) and Osterix expression were measured in MC3T3-E1 cells. The actin ring structures, tartrate-resistant acid phosphatase (TRAP) activity, and the nuclear factor of activator T-cells, cytoplasm 1 (NFATc1) expression were evaluated in RAW 264.7 cells. Ovariectomized ICR mice were orally administered FJH-UBS for eight weeks. The bone mineral density (BMD) and the serum levels of osteocalcin, procollagen 1 N-terminal propeptide (P1NP), osteoprotegerin, and TRAP 5b were analyzed.

RESULTS

FJH-UBS increased the ALP activity, collagen, osteocalcin, mineralization, and RUNX2 and osterix expression in MC3T3-E1 osteoblastic cells, whereas it decreased the TRAP activity, actin ring structures, and NFATc1 expression in RAW 264.7 osteoclastic cells. In ovariectomy-induced osteoporosis mice, FJH-UBS positively restored all of the changes in the bone metabolism biomarkers (BMD, osteocalcin, P1NP, osteoprotegerin, and TRAP 5b) caused by the ovariectomy.

CONCLUSION

FJH-UBS has anti-osteoporotic activity by promoting osteoblast activity and inhibiting osteoclast activity in vitro and in vivo, suggesting that FJH-UBS is a potential functional food ingredient for osteoporosis.

Bone regeneration in osteoporosis: opportunities and challenges

Osteoporosis is a bone disorder characterised by low bone mineral density, reduced bone strength, increased bone fragility, and impaired mineralisation of bones causing an increased risk of bone fracture. Several therapies are available for treating osteoporosis which include bisphosphonates, anti-resorptive agents, oestrogen modulators, etc. These therapies primarily focus on decreasing bone resorption and do not assist in bone regeneration or offering permanent curative solutions. Additionally, these therapies are associated with severe adverse events like thromboembolism, increased risk of stroke, and hypocalcaemia. To overcome these limitations, bone regenerative pathways and approaches are now considered to manage osteoporosis. The bone regenerative pathways involved in bone regeneration include wingless-related integration site/β-catenin signalling pathway, notch signalling pathway, calcium signalling, etc. The various regenerative approaches which possess potential to heal and replace the bone defect site include scaffolds, cements, cell therapy, and other alternative medicines. The review focuses on describing the challenges and opportunities in bone regeneration for osteoporosis.

The Lignan-Rich Fraction from Sambucus williamsii Hance Exerts Bone Protective Effects via Altering Circulating Serotonin and Gut Microbiota in Rats

Our previous study revealed that the bone anabolic effects of the lignan-rich fraction (SWCA) from Sambucus williamsii Hance was involved in modulating the metabolism of tryptophan in vivo and inhibiting serotonin (5-HT) synthesis in vitro. This study aimed to determine how SWCA modulates bone metabolism via serotonin in vivo. The effects of SWCA were evaluated by using 4-month-old Sprague-Dawley (SD) ovariectomized rats. The serum levels of 5-HT and kynurenine, the protein expressions of tryptophan hydroxylase 1 (TPH-1) and TPH-2, the genes and proteins related to the 5-HT signaling pathway as well as gut microbiota composition were determined. SWCA treatment alleviated bone loss and decreased serum levels of serotonin, which was negatively related to bone mineral density (BMD) in rats. It suppressed the protein expression of TPH-1 in the colon, and reversed the gene and protein expressions of FOXO1 and ATF4 in the femur in OVX rats, while it did not affect the TPH-2 protein expression in the cortex. SWCA treatment escalated the relative abundance of Antinobacteria and modulated several genera relating to BMD. These findings verified that the bone protective effects of lignans were mediated by serotonin, and provided evidence that lignans might be a good source of TPH-1 inhibitors.

Antiosteoporosis effect of tanshinol in osteoporosis animal models: A systematic review and meta-analysis

Background: Osteoporosis (OP) is an age-related bone disease that has emerged as a worldwide public health concern due to its increasing incidence and high disability rate. Tanshinol [D (+) β-3,4-dihydroxyphenyl lactic acid, TS], a water-soluble component extracted from Salvia miltiorrhiza, has proven to be effective in attenuating OP in vitro and in vivo. However, there is insufficient evidence to support its clinical application.

Objective: This meta-analysis aimed to investigate available OP animal model studies to demonstrate the antiosteoporosis effects of TS in a systematic manner.

Methods: Electronic searches of related studies were conducted in the following databases: EMBASE, PubMed, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure, Chinese VIP Database, Chinese Biomedical Literature Database, and Wanfang. The retrieval date was January 2022, and there were no time or language restrictions. The CAMARADES 10-item quality checklist was utilized to test the risk of potential bias for each study, and modifications were performed accordingly. The primary outcome was bone mineral density (BMD, which included the femur and lumbar spine); and secondary outcomes were parameters for trabecular bone such as bone volume over total volume (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), conditions of the femur (including bone maximum load and bone elastic load), and markers of bone metabolism (serum osteocalcin, S-OCN).

Results: A total of nine studies including 176 rats were chosen for this analysis. Egger’s test revealed the presence of publication bias in various studies regarding the primary outcome. According to this systematic review, TS significantly increased the BMD of the femur (BMD-femur) (SMD = 4.40; 95% CI = 1.61 to 7.19; p = 0.002, I² = 94.6%), BMD of the lumbar spine (BMD-lumbar) (SMD = 6.390; 95% CI = 2.036 to 10.744; p = 0.004, I² = 95.9%), BV/TV (SMD = 0.790; 95% CI = 0.376 to 1.204; p = 0.000, I² = 10.8), Tb.N (SMD = 0.690; 95% CI = 0.309 to 1.071; p = 0.000, I² = 12%), Tb.Th (SMD = 0.772; 95% CI = 0.410 to 1.134; p = 0.000, I² = 32.2%), and S-OCN (SMD = 3.13; 95% CI = 0.617 to 5.65; p = 0.015, I² = 92.3%), while the Tb.Sp level was markedly decreased in OP models in comparison to the controls (SMD = −0.822; 95% CI = −1.207 to −0.437; p = 0.000, I² = 0%). Moreover, TS treatment was associated with a significant improvement of the bone biomechanical indicators, including bone maximum load (SMD = 0.912; 95% CI = 0.370 to 1.455; p = 0.001, I² = 40%) and elasticity load (SMD = 0.821; 95% CI = 0.290 to 1.351; p = 0.002, I² = 0%).

Conclusion: Collectively, our findings suggest that TS can improve BMD, bone microarchitecture, bone biomechanics, and S-OCN expression in rats, implying that it could be used clinically in the future.

Systematic Review Registration:https://inplasy.com/inplasy-2022-3-0053/, identifier [INPLASY202230053].

Prenylated Isoflavonoids-Rich Extract of Erythrinae Cortex Exerted Bone Protective Effects by Modulating Gut Microbial Compositions and Metabolites in Ovariectomized Rats

Flavonoids, found in a wide variety of foods and plants, are considered to play an important role in the prevention and treatment of osteoporosis. Our previous studies demonstrated that Erythrina cortex extract (EC) rich in prenylated isoflavonoids exerted bone protective effects in ovariectomized (OVX) rats. The present study aimed to investigate the interactions of gut microbiota with the EC extract to explore the underlying mechanisms involved in its beneficial effects on bone. Sprague-Dawley female rats of 3-months-old were ovariectomized and treated with EC extract for 12 weeks. EC extract reversed ovariectomy-induced deterioration of bone mineral density and bone microarchitecture as well as downregulated cathepsin K (Ctsk) and upregulated runt-related transcription factor 2 (Runx2) and alkaline phosphatase (ALP) in the tibia of OVX rats. Its protective effects on bone were correlated with changes in microbial richness and the restorations of several genera. EC increased the serum circulating levels of acetate and propionate in OVX rats. We conclude that the bone protective effects of EC extract were associated with the changes in microbial compositions and serum short chain fatty acids (SCFAs) in OVX rats.

Dietary interventions for better management of osteoporosis: An overview

Osteoporosis is a public health concern and a cause of bone loss, increased risk of skeletal fracture, and a heavy economic burden. It is common in postmenopausal women and the elderly and is impacted by dietary factors, lifestyle and some secondary factors. Although many drugs are available for the treatment of osteoporosis, these therapies are accompanied by subsequent side effects. Hence, dietary interventions are highly important to prevent osteoporosis. This review was aimed to provide a comprehensive understanding of the roles of dietary nutrients derived from natural foods and of common dietary patterns in the regulation of osteoporosis. Nutrients from daily diets, such as unsaturated fatty acids, proteins, minerals, peptides, phytoestrogens, and prebiotics, can regulate bone metabolism and reverse bone loss. Meanwhile, these nutrients generally existed in food groups and certain dietary patterns also play critical roles in skeletal health. Appropriate dietary interventions (nutrients and dietary patterns) could be primary and effective strategies to prevent and treat osteoporosis across the lifespan for the consumers and food enterprises.

Genistein prevents bone loss in type 2 diabetic rats induced by streptozotocin

Background

Diabetic osteoporosis has become a severe public health problem in the aging societies. Genistein has been reported to play an important role in preventing and treating metabolic diseases via its anti-inflammatory, antioxidant, anti-estrogenic, and estrogen-like functions.

Objective

We aimed to investigate whether genistein exerts bone-protective effect on diabetic rats induced by 35 mg/kg streptozotocin (STZ) plus a 4-week high-fat diet.

Design

Sprague–Dawley rats were randomly divided into four groups: (1) control group, (2) type 2 diabetes mellitus (T2DM) model group, (3) T2DM with 10 mg/kg genistein, and (4) T2DM with 30 mg/kg genistein. After an 8-week treatment with genistein, the femurs, tibias, and blood were collected from all rats for further analysis.

Results

Genistein at 10 mg/kg showed little effect on diabetic osteoporosis, whereas genistein at 30 mg/kg significantly improved glucose and bone metabolisms compared with diabetic rats. Our results showed that 30 mg/kg genistein significantly increased bone mineral density, serum osteocalcin, and bone alkaline phosphatase. Genistein also effectively lowered fasting blood glucose, tartrate-resistant acid phosphatase 5b, tumor necrosis factor-α, interleukin-6, and numbers of adipocytes and osteoclasts. Compared with the T2DM group, protein levels of receptor activator of nuclear factor κB ligand (RANKL) and peroxisome proliferator-activated receptor-γ (PPAR-γ) were decreased, while protein levels of osteoprotegerin (OPG), β-catenin, and runt-related transcription factor 2 (Runx-2) were increased after genistein intervention.

Conclusion

Genistein could effectively improve abnormal bone metabolism in STZ-induced diabetic rats; the underlying molecular mechanisms might be related to OPG/RANKL, PPAR-γ, and β-catenin/Runx-2 pathways.

Ameliorative effects of quercetin on folliculogenesis in diabetic mice: a stereological study

A high risk of reproductive disorders can be seen in diabetic pregnancy. Reproductive disorders associated with diabetes may result from alterations in the function of the ovary. In this study, we investigated the ameliorative effects of quercetin as a phytoestrogen and antidiabetic agent on the folliculogenesis in diabetic mice. Streptozotocin-induced diabetic mice were treated with 30 mg/kg/day quercetin for four weeks. The volume of ovary, follicles, and corpus luteum were significantly decreased in the diabetic mice. The number of growing follicles (secondary, antral, and Graafian follicles) and corpus luteum was significantly decreased in the diabetic mice. Also, the volume of oocytes was significantly decreased in antral and Graafian follicles. Our results indicated that the administration of quercetin in diabetic mice increased the volume of the ovary and growing follicles, the number of growing follicles and corpus luteum. It also significantly decreased the number of atretic follicles. As a result, it may be concluded that the impaired follicular growth and development caused by hyperglycemia in diabetic mice can be alleviated by quercetin treatment.

Network Pharmacology to Identify the Pharmacological Mechanisms of a Traditional Chinese Medicine Derived from Trachelospermum jasminoides in Patients with Rheumatoid Arthritis

BACKGROUND This study used a network pharmacology approach to identify the pharmacological mechanisms of a traditional Chinese medicine derived from Trachelospermum jasminoides (Lindl.) Lem. in patients with rheumatoid arthritis (RA). MATERIAL AND METHODS Known compounds of T. jasminoides were obtained from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database, the Shanghai Institute of Organic Chemistry of Chinese Academy of Science, Chemistry (CASC) database, and a literature search. Putative targets of identified compounds were predicted by SwissTargetPrediction. RA-related targets were achieved from the Therapeutic Target database, Drugbank database, Pharmacogenomics Knowledgebase, and Online Mendelian Inheritance in Man database. The protein-protein interaction (PPI) network was built by STRING. CluGO was utilized for Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analysis. RESULTS A total of 354 potential targets were predicted for the 17 bioactive compounds in T. jasminoides; 69 of these targets overlapped with RA-related targets. A PPI network was composed and 2 clusters of 59 and 42 nodes each were excavated. GO and KEGG enrichment analysis of the overlapping targets and the 2 clusters was mainly grouped into immunity, inflammation, estrogen, anxiety, and depression processes. CONCLUSIONS Our study illustrated that T. jasminoides alleviates RA through the interleukin-17 signaling pathway, the tumor necrosis factor signaling pathway, and other immune and inflammatory-related processes. It also may exert effects in regulating cell differentiation and potentially has anti-anxiety, anti-depression, and estrogen-like effects.

Microarchitectural changes in the mandibles of ovariectomized rats: a systematic review and meta-analysis

Background

This study aimed to examine radiologic microarchitectural changes in the mandibles of ovariectomized (OVX) rats through a systematic review and meta-analysis and to identify factors of the OVX rat model that influence on the bone microstructure.

Methods

Eligible articles were identified by searching electronic databases, including Embase, Medline, Web of Science, and KoreaMed, for articles published from January 1966 to November 2017. Two reviewers independently performed study selection, data extraction, and quality assessment. The pooled standardized mean difference (SMD) with 95% confidence intervals was calculated using a random-effects model. Subgroup analysis and meta-regression were performed to explore the effect of potential sources on the outcomes. The reliability of the results was assessed by sensitivity analysis and publication bias.

Results

Of 1160 studies, 16 studies (120 OVX and 120 control rats) were included in the meta-analysis. Compared to the control group, the OVX rats’ trabecular bone volume fraction (SMD = − 2.41, P < 0.01, I² = 81%), trabecular thickness (SMD = − 1.73, P < 0.01, I² = 73%) and bone mineral density (SMD = − 0.95, P = 0.01, I² = 71%) displayed the bone loss consistent with osteoporosis. The trabecular separation (SMD = 1.66, P < 0.01, I² = 51%) has widen in the OVX mandibular bone in comparison to the control group. However, the trabecular number showed no indication to detect the osteoporosis (SMD = − 0.45, P = 0.38, I² = 76%). The meta-regression indicated that longer post-OVX periods led to greater changes in bone mineral density (β = − 0.104, P = 0.017). However, the rats’ age at OVX was not linked to bone microstructure change.

Conclusions

Using meta-regression and sensitivity analysis techniques, heterogeneity across the micro CT studies of OVX-induced osteoporosis was found. The major factors of heterogeneity were the region of interest and post-OVX period. Our assessment can assist in designing experiments to maximize the usefulness of OVX rat model.

Protective effect of Glycyrrhiza glabra roots extract on bone mineral density of ovariectomized rats

Objective: The aim of this study was to evaluate the potential effect of the methanolic extract of plant Glycyrrhiza glabra roots on bone mineral density and femoral bone strength of ovariectomized rats.

Methods: Thirty 10-month-old Wistar rats were randomly separated into three groups of ten, Control, Ovariectomy and Ovariectomy-plus-Glycyrrhiza in their drinking water. Total and proximal tibial bone mineral density was measured in all groups before ovariectomy (baseline) and after 3 and 6 months post ovariectomy. Three-point-bending of the femurs and uterine weight and histology were examined at the end of the study.

Results: No significant difference was noted in bone density percentage change of total tibia from baseline to 3 months between Control and Ovariectomy-plus-Glycyrrhiza groups (+5.31% ± 4.75 and +3.30% ± 6.31 respectively, P = non significant), and of proximal tibia accordingly (+5.58% ± 6.92 and +2.61% ± 13.62, P = non significant) demonstrating a strong osteoprotective effect. There was notable difference in percentage change of total tibia from baseline to 6 months between groups Ovariectomy and Ovariectomy-plus-Glycyrrhiza (−13.03% ± 5.11 and −0.84% ± 7.63 respectively, P < 0.005), and of proximal tibia accordingly (−27.9% ± 3.69 and −0.81% ± 14.85 respectively, P < 0.001), confirming the protective effect of Glycyrrhiza glabra extract in preserving bone density of the Ovariectomy-plus-Glycyrrhiza group. Three-point-bending did not reveal any statistically significant difference between Ovariectomy and Ovariectomy-plus-Glycyrrhiza groups. Uterine weights of the Ovariectomy-plus-Glycyrrhiza group ranged between the other two groups with no statistically significant difference to each.

Conclusions: Glycyrrhiza glabra root extract notably protected tibial bone mineral density loss in Ovariectomy-plus-Glycyrrhiza rats in comparison with ovariectomized rats, but did not improve biomechanical strength.

Identification and characterization of a polysaccharide from the roots of Morinda officinalis, as an inducer of bone formation by up-regulation of target gene expression

Morinda officinalis is an important traditional tonic herbal medicine. In the present study, we found that crude polysaccharides extracted from M. officinalis, named MO90, could significantly increase the bone mineral density (BMD) of the whole femur, distal femur, and proximal femur in ovariectomized (OVX) rats. In addition, MO90 decreased the level of bone turnover markers and prevented the deterioration of trabecular microarchitecture. To investigate the fractions responsible for anti-osteoporosis activity, one novel inulin-type fructan, MOW90-1, was isolated from MOP90. Structural analysis indicated that MOW90-1 consists of a backbone of (2→1)-linked-β-D-Fruf, and is terminated with (1→)-linked-α-D-Glcp and (2→)-linked-β-D-Fruf. Furthermore, an in vitro anti-osteoporosis assay indicated that MOW90-1 promoted proliferation, differentiation, and mineralization of MC3T3-E1 cells by up-regulating the expression of runt-related transcription factor 2, osterix, osteopontin, and osteocalcin. In conclusion, our studies provide supporting evidence for future use of this novel M. officinalis fructan as a key nutrient of health products.

Ibandronate Treatment Before and After Implant Insertion Impairs Osseointegration in Aged Rats with Ovariectomy Induced Osteoporosis

Excessive decreases in bone volume (BV) and bone mineral density (BMD) can lead to osteoporosis, potentially hindering implant osseointegration. Bisphosphonates are commonly used to combat osteoporosis by slowing osteoclast-mediated resorption; however, functional osteoclasts are integral to bone remodeling and, thus, implant osseointegration, potentially contraindicating bisphosphonate use during implantation. To optimize the use of implant technologies in patients with compromised bone structure and metabolism, we need a more complete understanding of the biological response to surface design. The goal of this study was to assess the effects of osteoporosis and bisphosphonates on osseointegration of titanium (Ti) implants with microstructured surfaces, which have been shown to support osteoblast differentiation in vitro and rapid osseointegration in vivo. Forty, 8-month-old, virgin, female CD Sprague Dawley rats underwent ovariectomy (OVX) or sham (SHOVX) surgery. After 5 weeks, animals were injected subcutaneously with either the bisphosphonate (BIS), Ibandronate (25 µg/kg), or phosphate-buffered saline (PBS) every 25 days. 1 week after the initial injection, Ø2.5mm × 3.5mm microrough (SLA; grit-blasted/acid etched) implants were placed transcortically in the distal metaphysis of each femur resulting in four groups: 1) SHOVX+PBS; 2) SHOVX+BIS; 3) OVX+PBS; and 4) OVX+BIS. After 28d, qualitative properties of the bone and implant osseointegration were assessed using micro-computed tomography (microCT), calcified histomorphometry (Van Gieson's stain), and removal torque testing. microCT revealed decreased bone volume in OVX rats, which was slowed by bisphosphonate treatment. Reduced bone-to-implant contact (BIC) was evident in OVX+PBS compared to SHOVX+PBS. Although BV/TV was increased in OVX+BIS compared to OVX+PBS, bisphosphonate treatment had no effect on BIC. Removal torque testing revealed a higher maximum torque, torsional stiffness, and torsional energy in SHOVX compared to OVX with no effects due to bisphosphonate treatment. Our results show that osseointegration is decreased in osteoporotic animals. Ibandronate halts the progression of osteoporosis but does not enhance osseointegration. © 2019 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Black Rice (Oryza sativa L.) Fermented with Lactobacillus casei Attenuates Osteoclastogenesis and Ovariectomy-Induced Osteoporosis

The aim of the present study was to investigate the antiosteoclastogenic effects of black rice (Oryza sativa L.) fermented with Lactobacillus casei (LAB) in RANKL-induced RAW macrophage cells and its antiosteoporosis activity against ovariectomy-induced osteoporosis in rats. LAB extract (LABE) treatment attenuated receptor activator of nuclear factor-kappa B (NF-κB) ligand-induced osteoclastic differentiation in RAW cells by inhibiting intercellular reactive oxygen species generation and downregulating the activation of mitogen-activated protein kinases and NF-κB, leading to the downregulation of c-Fos and expression of nuclear factor of activated T cells c1. This consequently suppressed the expression of osteoclast-specific genes including those for cathepsin K, tartrate-resistant acid phosphatase, calcitonin receptor, and integrin β3. Oral administration of LABE protected against ovariectomy-induced bone loss by significantly inhibiting bone architecture alterations and improving serum bone turnover markers in ovariectomized rats. The findings suggest that the antiosteoporotic activity of LABE may be derived from its antiosteoclastic and anti-bone-resorptive activities. LABE has potential as a promising functional material or substrate to prepare protective agents for osteoporosis and osteoclast-mediated bone diseases.

Effect of isoflavone-enriched whole soy milk powder supplementation on bone metabolism in ovariectomized mice

BACKGROUND/OBJECTIVE

There is intense interest in soy isoflavone as a hormone replacement therapy for the prevention of postmenopausal osteoporosis. A new kind of isoflavone-enriched whole soy milk powder (I-WSM) containing more isoflavones than conventional whole soy milk powder was recently developed. The aim of this study was to investigate the effects of I-WSM on bone metabolism in ovariectomized mice.

MATERIALS/METHODS

Sixty female ICR mice individually underwent ovariectomy (OVX) or a sham operation, and were randomized into six groups of 10 animals each as follows: Sham, OVX, OVX with 2% I-WSM diet, OVX with 10% I-WSM diet, OVX with 20% I-WSM diet, and OVX with 20% WSM diet. After an 8-week treatment period, bone mineral density (BMD), calcium, alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP) 5b, osteocalcin (OC), procollagen 1 N-terminal propeptide (P1NP), and osteoprotegenin (OPG) were analyzed.

RESULTS

BMD was significantly lower in the OVX group compared to the Sham group but was significantly higher in OVX + 10% I-WSM and OVX + 20% I-WSM groups compared to the OVX group (P < 0.05). Serum calcium concentration significantly increased in the OVX + 10% and 20% I-WSM groups. Serum ALP levels were significantly lower in the OVX + 10% and 20% I-WSM groups compared to the other experimental groups (P < 0.05). OC was significantly reduced in the OVX group compared to the Sham group (P < 0.05), but a dose-dependent increase was observed in the OVX groups supplemented with I-WSM. P1NP and OPG levels were significantly reduced, while TRAP 5b level was significantly elevated in the OVX group compared with the Sham group, which was not affected by I-WSM (P < 0.05).

CONCLUSIONS

This study suggests that I-WSM supplementation in OVX mice has the effect of preventing BMD reduction and promoting bone formation. Therefore, I-WSM can be used as an effective alternative to postmenopausal osteoporosis prevention.

Combined Effects of Phytoestrogen Genistein and Silicon on Ovariectomy-Induced Bone Loss in Rat

This study was performed to evaluate the effect of concomitant supplementation of genistein and silicon on bone mineral density and bone metabolism-related markers in ovariectomized rat. Three-month-old Sprague Dawley female rats were subjected to bilateral ovariectomy (OVX) or sham surgery, and then the OVX rats were randomly divided into four groups: OVX-GEN, OVX-Si, OVX-GEN-Si, and OVX. Genistein and silicon supplementation was started immediately after OVX and continued for 10 weeks. In the OVX-GEN group, 5 mg genistein per gram body weight was injected subcutaneously. The OVX-Si group was given soluble silicon daily in demineralized water (Si 20 mg/kg body weight/day). The OVX-GEN-Si group was given subcutaneous injections of 5 mg genistein per gram body weight, at the same time, given soluble silicon daily (Si 20 mg/kg body weight/day). The results showed that the genistein supplementation in the OVX rats significantly prevented the loss of uterus weight; however, the silicon supplementation showed no effect on the uterus weight loss. The lumbar spine and femur bone mineral density was significantly decreased after OVX surgery; however, this decrease was inhibited by the genistein and/or silicon, and the BMD of the lumbar spine and femur was the highest in the OVX-GEN-Si-treated group. Histomorphometric analyses showed that the supplementation of genistein and/or silicon restored bone volume and trabecular thickness of femoral trabecular bone in the OVX group. Besides, the treatment with genistein and silicon for 10 weeks increased the serum levels of calcium and phosphorus in the OVX rats; serum calcium and serum phosphorus in the OVX-GEN-Si group were higher than those in the OVX-GEN and OVX-Si group (P < 0.05). At the same time, the treatment with genistein and/or silicon decreased serum alkaline phosphatase (ALP) and osteocalcin, which were increased by ovariectomy; serum ALP and osteocalcin in the OVX-GEN-Si group were lower than those in the OVX-GEN and OVX-Si groups (P < 0.05). The results above indicate that genistein and silicon have synergistic effects on bone formation in ovariectomized rats.

Oral administration of kaempferol inhibits bone loss in rat model of ovariectomy-induced osteopenia

BACKGROUND

Postmenopausal osteoporosis and osteoporotic fractures constitute an increasing problem in developing countries. Kaempferol, isolated from seeds of Cuscuta chinensis, is an active flavonoid inhibiting in vitro osteoclast activity. The aim of the presented research was an assessment of kaempferol effect on estrogen-deficiency-induced bone structure disturbances in rats.

METHODS

The study was performed on 24 Wistar female rats divided into 3 groups: SHAM - rats undergoing a "sham" surgery, OVX-C - control group of animals that underwent ovariectomy, OVX-K - rats undergoing ovariectomy and receiving kaempferol for 8 weeks (from day 56 to day 112).

RESULTS

In the OVX-K group, contrary to the OVX-C one, there was no significant decrease in femoral bone mineral density (BMD). A significant increase in Young's modulus was observed in the OVX-K group compared to the OVX-C (15.33±2.51GPa vs. 11.14±1.93GPa, p<0.05). A decreased bone turnover was detected in the OVX-K group. Tissue volume ratio (BV/TV) and trabecular bone perimeter were increased in the OVX-K group compared to the OVX-C one (0.241±0.037 vs. 0.170±0.022, p<0.05 and 15.52±2.78mm vs. 9.67±3.07mm, p<0.05, respectively).

CONCLUSION

Kaempferol has a beneficial influence on estrogen-deficiency-induced disturbances of bone structure in rats.

Jumping exercise preserves bone mineral density and mechanical properties in osteopenic ovariectomized rats even following established osteopenia

The effects of jump training on bone structure before and after ovariectomy-induced osteopenia in rats were investigated. Jumping exercise induced favorable changes in bone mineral density, bone mechanical properties, and bone formation/resorption markers. This exercise is effective to prevent bone loss after ovariectomy even when osteopenia is already established.

INTRODUCTION

The present study investigated the effects of jump training on bone structure before and after ovariectomy-induced osteopenia in 80 10-week-old Wistar rats.

METHODS

Forty rats (prevention program) were randomly allocated to one of four equal groups (n = 10): sham-operated sedentary (SHAM-SEDp), ovariectomized (OVX) sedentary (OVX-SEDp), sham-operated exercised (SHAM-EXp), and OVX exercised (OVX-EXp). SHAM-EXp and OVX-EXp animals began training 3 days after surgery. Another 40 rats (treatment program) were randomly allocated into another four groups (n = 10): sham-operated sedentary (SHAM-SEDt), OVX sedentary (OVX-SEDt), sham-operated exercised (SHAM-EXt), and OVX exercised (OVX-EXt). SHAM-EXt and OVX-EXt animals began training 60 days after surgery. The rats in the exercised groups jumped 20 times/day, 5 days/week, to a height of 40 cm for 12 weeks. At the end of the experimental period, serum osteocalcin, follicle-stimulating hormone (FSH) dosage, dual X-ray absorptiometry (DXA), histomorphometry, and biomechanical tests were analyzed.

RESULTS

The OVX groups showed higher values of FSH and body weight (p < 0.05). DXA showed that jump training significantly increased bone mineral density of the femur and fifth lumbar vertebra (p < 0.05). The stiffness of the left femur and fifth lumbar vertebra in the exercised groups was greater than that of the sedentary groups (p < 0.05). Ovariectomy induced significant difference in bone volume (BV/TV, percent), trabecular separation (Tb.Sp, micrometer), and trabecular number (Tb.N, per millimeter) (p < 0.05) compared to sham operation. Jump training in the OVX group induced significant differences in BV/TV, Tb.Sp, and Tb.N and decreased osteoblast number per bone perimeter (p < 0.05) compared with OVX nontraining, in the prevention groups. Osteocalcin dosage showed higher values in the exercised groups (p < 0.05).

CONCLUSIONS

Jumping exercise induced favorable changes in bone mineral density, bone mechanical properties, and bone formation/resorption markers. Jump training is effective to prevent bone loss after ovariectomy even when osteopenia is already established.

Effects of neonatal 17α-ethinyloestradiol exposure on female-paced mating behaviour in the rat

Correct perinatal oestrogen levels are critical for sexual differentiation. For example, perinatal exposure to oestrogen causes masculinization and defeminization of the brain in female rats and also induces delayed effects after maturation characterized by early onset of abnormal oestrus cycling. However, the mechanisms underlying the above effects of oestrogen remain to be fully determined. 17α-ethinyloestradiol (EE), a common synthetic oestrogen widely used in oral contraceptives, binds specifically to oestrogen receptors. In this study, we demonstrated the effects of a single neonatal injection of high- or low-dose EE on reproductive behaviours. Female rats within 24 h after birth were subcutaneously injected with sesame oil, EE (0.02, 2 mg kg^-1 ) and 17β-oestradiol (E₂ ) (20 mg kg^-1 ). Between 11 and 15 weeks of age, sexual behaviour was tested twice in a paced mating situation. Latency to enter, lordosis and soliciting behaviour were recorded. Both high-dose EE- and E₂ -treated females showed a significantly lower lordosis quotient, decreased soliciting behaviours, increased rejection and fighting numbers. Accessibility to males was also delayed by neonatal E₂ exposure, although it was shortened by high-dose EE exposure. In contrast, low-dose EE-treated females did not exhibit impaired sexual behaviour. These results suggest that single neonatal exposure to a high dose of EE or E₂ disturbs the normal development of the female brain, resulting in impaired sexual behaviours in a female-paced mating situation. Besides, the differences noted between high-dose EE- and E₂ -treated females might be caused by different affinities of the oestrogen receptors, metabolic rates or mechanisms of action. Copyright © 2017 John Wiley & Sons, Ltd.

Botanicals and Their Bioactive Phytochemicals for Women's Health

Botanical dietary supplements are increasingly popular for women's health, particularly for older women. The specific botanicals women take vary as a function of age. Younger women will use botanicals for urinary tract infections, especially Vaccinium macrocarpon (cranberry), where there is evidence for efficacy. Botanical dietary supplements for premenstrual syndrome (PMS) are less commonly used, and rigorous clinical trials have not been done. Some examples include Vitex agnus-castus (chasteberry), Angelica sinensis (dong quai), Viburnum opulus/prunifolium (cramp bark and black haw), and Zingiber officinale (ginger). Pregnant women have also used ginger for relief from nausea. Natural galactagogues for lactating women include Trigonella foenum-graecum (fenugreek) and Silybum marianum (milk thistle); however, rigorous safety and efficacy studies are lacking. Older women suffering menopausal symptoms are increasingly likely to use botanicals, especially since the Women's Health Initiative showed an increased risk for breast cancer associated with traditional hormone therapy. Serotonergic mechanisms similar to antidepressants have been proposed for Actaea/Cimicifuga racemosa (black cohosh) and Valeriana officinalis (valerian). Plant extracts with estrogenic activities for menopausal symptom relief include Glycine max (soy), Trifolium pratense (red clover), Pueraria lobata (kudzu), Humulus lupulus (hops), Glycyrrhiza species (licorice), Rheum rhaponticum (rhubarb), Vitex agnus-castus (chasteberry), Linum usitatissimum (flaxseed), Epimedium species (herba Epimedii, horny goat weed), and Medicago sativa (alfalfa). Some of the estrogenic botanicals have also been shown to have protective effects against osteoporosis. Several of these botanicals could have additional breast cancer preventive effects linked to hormonal, chemical, inflammatory, and/or epigenetic pathways. Finally, although botanicals are perceived as natural safe remedies, it is important for women and their healthcare providers to realize that they have not been rigorously tested for potential toxic effects and/or drug/botanical interactions. Understanding the mechanism of action of these supplements used for women's health will ultimately lead to standardized botanical products with higher efficacy, safety, and chemopreventive properties.

Estrogenic Receptor-Functionalized Magnetite Nanoparticles for Rapid Separation of Phytoestrogens in Plant Extracts

With growing interests of phytoestrogens, many natural phytochemicals extracted from diverse plant species have been explored for their estrogenic-like activities and potential applications. In this work, a simple and rapid separation of phytoestrogenic compounds from crude plant extracts was purposed using magnetic nanoparticles (MNPs) of Fe₃O₄ immobilized with the ligand-binding domain (LBD) of estrogen receptor alpha (ERα). The recombinant LBD-ERα peptide of 40 kDa was produced and subsequently covalently linked to MNPs. One milligram of the LBD-ERα-immobilized MNPs demonstrated a specific binding to the standard 17β-estradiol (E2) of 3.37 nmol and 91.3-100 % of the bound E2 were subsequently recovered. LBD-ERα-immobilized MNPs could separate phytoestrogens of 4.6 nmol E2-equivalent activity from a 1-mg crude extract of Asparagus racemosus. The produced MNPs showed no separation yield when were applied to the negative controls, the crude extract of radish (Raphanus sativus), and the standard progesterone (P4). Thin-layer chromatography demonstrated a single phytochemical band of the separated phytoestrogens, which exhibited the activity to promote MCF-7 cell proliferation at 4.7 folds greater than the crude A. racemosus extract. The results of this work demonstrated a simple method to specifically separate phytoestrogens from crude plant extracts via the LBD-ERα-immobilized MNPs.

Sialoglycoprotein Isolated from Eggs of Carassius auratus Ameliorates Osteoporosis: An Effect Associated with Regulation of the Wnt/β-Catenin Pathway in Rodents

In the current study, ovariectomized (OVX) rats and the senescence-accelerated mouse strain P6 (SAMP6) were employed to establish models of postmenopausal osteoporosis and senile osteoporosis, respectively. The effects of treatment with sialoglycoprotein isolated from the eggs of Carassius auratus (Ca-SGP) on these two types of osteoporosis were investigated in vivo. Results showed that Ca-SGP significantly increased bone mineral density, ameliorated trabecular bone microstructure, and improved bone biomechanical properties in both OVX rats and SAMP6. The osteogenesis related Wnt/β-catenin pathway was targeted to study the underlying mechanism of Ca-SGP activity. In postmenopausal osteoporosis, Ca-SGP suppressed the activation of Wnt/β-catenin signal via down-regulating the expression of key genes including LRP5, β-catenin, and Runx2, suggesting that overactive osteogenesis was controlled by Ca-SGP. The bone formation was sharply weakened in senile osteoporosis, whereas Ca-SGP treatment promoted osteoblast activity by stimulating the Wnt/β-catenin signal. In conclusion, Ca-SGP ameliorated these two types of osteoporosis by normalizing bone anabolism.

Efficacy of proline in the treatment of menopause

The amino acids in the placenta have multiple functions; however, the therapeutic effects of proline remain poorly for relief postmenopausal symptoms. The aim of present study was to evaluate the effects of proline in the treatment of menopause using in vitro and in vivo models. We assessed the therapeutic effects and regulatory mechanisms of proline by using MCF-7 estrogen-dependent cells, MG63 osteoblast cells, and ovariectomized mice model. An in vivo study was carried out in eight-week-old sham and ovariectomized group. The ovariectomized mouse was further subdivided into two groups administered orally with 17β-estradiol or proline (10 mg/kg/day) for eight weeks. Proline significantly increased cell proliferation and Ki-67 levels in MCF-7 cells and enhanced cell proliferation, alkaline phosphatase activity, extracellular signal-regulated kinase phosphorylation, and glutamyl-prolyl-tRNA synthetase activation in MG63 cells. The estrogen receptor-β and estrogen-response elements luciferase activity were significantly increased by proline in MCF-7 and MG63 cells. In ovariectomized mice, oral administration of proline (10 mg/kg/day) for eight weeks significantly reduced body and vaginal weights. Proline also significantly increased serum estradiol and alkaline phosphatase levels, whereas serum luteinizing hormone was decreased by proline. In addition, detailed microcomputed tomography analysis showed that the proline notably enhanced bone mineral density, trabecular bone volume, and trabecular number in ovariectomized mice. Those findings implied that proline can be a promising candidate for the treatment of menopause.

Estrogen-like osteoprotective effects of glycine in in vitro and in vivo models of menopause

Recently, the placenta mesotherapy has been widely used to treat menopause. Placenta contains amino acids, peptides, minerals, and estrogen. Here, we investigated the estrogen-like osteoprotective effects of glycine (a main ingredient of placenta) in in vitro and in vivo models of menopause. We assessed the effect of glycine on MG-63 osteoblast cell line, MCF-7 estrogen-dependent cell line, and ovariectomized (OVX) mice. Glycine significantly increased the MG-63 cell proliferation in a dose-dependent manner. Activity of alkaline phosphatase (ALP) and phosphorylation of extracellular-signal-regulated kinase were increased by glycine in MG-63 cells. Glycine also increased the BrdU-incorporation and Ki-67 mRNA expression in MCF-7 cells. Glycine induced the up-regulation of estrogen receptor-β mRNA expression and estrogen-response element-luciferase activity in MG-63 and MCF-7 cells. In OVX mice, glycine was administered orally at a daily dose of 10 mg/kg per day for 8 weeks. Glycine resulted in the greatest decrease in weight gain caused by ovariectomy. Meanwhile, vaginal weight reduced by ovariectomy was increased by glycine. Glycine significantly increased the ALP activity in OVX mice. MicroCT-analysis showed that glycine significantly enhanced bone mineral density, trabecular number, and connectivity density in OVX mice. Moreover, glycine significantly increased the serum 17β-estradiol levels reduced by ovariectomy. Glycine has an estrogen-like osteoprotective effect in menopause models. Therefore, we suggest that glycine may be useful for the treatment of menopause.

Cysteine Prevents Menopausal Syndromes in Ovariectomized Mouse

Cysteine (Cys) is well known to be involved in oxidation-reduction reactions, serving as a source of sulfides in the body. Amino acids are known to improve menopausal symptoms and significantly reduce morbidity. This study aims to find an unrevealed effect of Cys with estrogenic and osteogenic actions. Ovariectomized (OVX) mice were treated with Cys daily for 8 weeks. Estrogen-related and osteoporosis-related factors were analyzed in the vagina, serum, and tibia. Cys was treated in estrogen receptor (ER)-positive human osteoblast-like MG-63 cells and ER-positive human breast cancer Michigan Cancer Foundation-7 (MCF-7) cells. Cysteine administration ameliorated overweightness of the body and vaginal atrophy in the OVX mice. Cysteine increased the levels of alkaline phosphatase (ALP) and 17β-estradiol in the serum of the OVX mice and improved the bone mineral density in the OVX mice. In MG-63 cells, Cys increased the proliferation, ERβ messenger RNA (mRNA) expression, and estrogen response element (ERE) activity. Cysteine increased the ALP activity and the phosphorylation of extracellular signal-regulated kinase. In MCF-7 cells, Cys also increased the proliferation, ERβ mRNA expression, and ERE activity. Taken together, these results demonstrated that Cys has estrogenic and osteogenic activities in OVX mice, MG-63 cells, and MCF-7 cells. The novel insights gained here strongly imply the potential use of Cys as a new agent for postmenopausal women.

Markers of Bone Metabolism in Patients With Chronic Pancreatitis and Pancreatic Ductal Adenocarcinoma

There are no studies comparing some of the most important markers, such as vitamin D, parathormone, osteocalcin, bone alkaline phosphatase, and calcium, in patients with chronic benign and malignant pancreatic diseases. Our objective was to comparatively evaluate serum markers of bone metabolism in patients with chronic pancreatitis and in those with ductal pancreatic adenocarcinoma. Sixty-three consecutive subjects were studied: 30 patients with a firm diagnosis of chronic pancreatitis and 33 having histologically confirmed pancreatic adenocarcinoma. Serum 25-hydroxyvitamin D, bone alkaline phosphatase, osteocalcin, parathormone, and calcium were determined using commercially available kits. Taking into consideration the clinical variables of all 63 patients studied, 25-hydroxyvitamin D was inversely correlated with only the body mass index (P = 0.007), whereas it was not correlated with age (P = 0.583) or fecal elastase-1 concentrations (P = 0.556). Regarding the other substances studied, parathormone was positively correlated with only the age of the patients (P = 0.015). Of the 5 substances studied, only bone alkaline phosphates were significantly different (P < 0.001) between patients with chronic pancreatitis and those with pancreatic ductal adenocarcinoma. Within the 2 groups of patients, the 23 patients with chronic pancreatitis without diabetes mellitus had serum concentrations of 25-hydroxyvitamin D significantly lower (P = 0.045) than those with chronic pancreatitis having diabetes mellitus, whereas smokers with pancreatic ductal adenocarcinoma had serum concentrations of calcium significantly higher (P < 0.001) as compared to nonsmokers. Altered bone metabolism seems to be associated with chronic diseases of the pancreas; however, the mechanism should be better elucidated.