Alendronate promotes osteoblast differentiation and bone formation in ovariectomy-induced osteoporosis through interferon-β/signal transducer and activator of transcription 1 pathway

Bone quality in zebrafish vertebrae improves after alendronate administration in a glucocorticoid-induced osteoporosis model

Glucocorticoid-induced osteoporosis (GIOP) changes the microarchitecture of bones and often leads to the reduction of bone-mineral density (BMD) and increased fracture rates. Zebrafish has been used as an alternative model for GIOP, however, the interaction of GIOP, and its treatment, with zebrafish bone morphometrics and mechanical properties, remains a challenge. Thus, this study aimed to evaluate the effects of prednisolone and alendronate on the properties of zebrafish vertebrae. Adult 7-month-old zebrafish were distributed into four groups: control (CTRL), prednisolone-only (PN), alendronate-only (ALN), and the sequential use of both medicines (PN + ALN). Fish skeletons were scanned via micro-tomography (n = 3) to obtain vertebra morphometrics (e.g., BMD). Bone morphology was assessed using scanning electron microscopy (n = 4) and the biomechanical behaviour with nanoindentation technique (n = 3). The BMD decreased in PN (426.08 ± 18.58 mg/cm3) and ALN (398.23 ± 10.20 mg/cm3) groups compared to the CTRL (490.43 ± 41.96 mg/cm3) (p < 0.001); however, administering the medicines in sequence recovered the values to healthy levels (495.43 ± 22.06 mg/cm3) (p > 0.05). The bone layered structures remain preserved in all groups. The vertebrae of the groups that received ALN and PN + ALN, displayed higher modulus of elasticity (27.27 ± 1.59 GPa and 25.68 ± 2.07 GPa, respectively) than the CTRL (22.74 ± 1.60 GP) (p < 0.001). ALN alone increased the hardness of zebrafish vertebrae to the highest value among the treatments (1.32 ± 0.13 GPa) (p < 0.001). Conversely, PN + ALN (1.25 ± 0.11 GPa) showed unaltered hardness from the CTRL (1.18 ± 0.13 GPa), but significantly higher than the PN group (1.08 ± 0.12 GPa) (p < 0.001). ALN administered after GIOP development, rescued osteoporotic condition by recovering the BMD and bone hardness in zebrafish vertebrae.

Assessing bone formation on hydrophilic and hydrophobic implant surfaces in a murine model treated with bisphosphonates

OBJECTIVE

To evaluate the osseointegration of implants with hydrophobic (HFB) and hydrophilic (HFL) surfaces in a murine model of high-dose bisphosphonates (BPs).

MATERIALS AND METHODS

Sixty-four rats were randomly allocated into four groups: control group with HFB implants (CG-HFB), control group with HFL implants (CG-HFL), BP group with HFB implants (BP-HFB), and BP group with HFL implants (BP-HFL). Animals were euthanized after 15 and 45 days (n=8). The dependent variables assessed were the removal torque (biomechanical analysis), the bone volume around the implants (%BV/TV) (microtomographic analysis), the bone-implant contact (%BIC), the bone between the threads (%BBT) (histomorphometric analysis), and the expression of bone metabolism markers (immunohistochemistry analysis).

RESULTS

The CG-HFL and BP-HFL groups presented higher removal torque than the CG-HFB and BP-HFB implants. The %BIC of the CG-HFL surfaces was slightly higher than that of the CG-HFB implants. The BP-HFB and BP-HFL groups presented a higher %BIC than that of the CG-HFB and CG-HFL groups (p<0.001). BP therapy also increased the %BBT at both implant surfaces. Higher levels of ALP were observed in the matrix region of bone tissue on the HFL surfaces than on the HFB surfaces.

CONCLUSION

Both surfaces enable osseointegration in rats under BP therapy.

CLINICAL RELEVANCE

The study demonstrates that hydrophobic (HFB) and hydrophilic (HFL) implant surfaces can promote osseointegration in rats undergoing bisphosphonate therapy. The HFL surfaces exhibited improved biomechanical performance, higher bone-implant contact, and increased bone volume, suggesting their potential clinical relevance for implant success in individuals on bisphosphonate treatment.

Calcium carbonate-enriched pumpkin affects calcium status in ovariectomized rats

Calcium carbonate (CaCO₃)-enriched pumpkin may serve as a good source of calcium for patients diagnosed with osteoporosis. In this study, we aimed to determine the effect of CaCO₃-enriched pumpkin on Ca status in ovariectomized rats. The study included 40 female Wistar rats divided into five groups (n = 8). One group was fed with a standard diet (control group), while the other four groups were ovariectomized and received a standard diet (control ovariectomized group), or a diet containing CaCO₃-enriched pumpkin, alendronate, or both. The nutritional intervention lasted 12 weeks, and then the rats were euthanized. Tissue and blood samples were collected and assessed for the levels of total Ca, estradiol, parathyroid hormone, and procollagen type I N propeptide. In addition, a histological analysis was performed on femurs. The results of the study suggest that CaCO₃-enriched pumpkin can increase Ca content in femurs and improve bone recovery in ovariectomized rats. Furthermore, enriched pumpkin contributes to Ca accumulation in the kidneys, and this effect is more pronounced in combination with alendronate.

IFN-β mediates the anti-osteoclastic effect of bisphosphonates and dexamethasone

Zoledronic acid (Zol) is a potent bisphosphonate that inhibits the differentiation of monocytes into osteoclasts. It is often used in combination with dexamethasone (Dex), a glucocorticoid that promotes the resolution of inflammation, to treat malignant diseases, such as multiple myeloma. This treatment can result in bone pathologies, namely medication related osteonecrosis of the jaw, with a poor understanding of the molecular mechanism on monocyte differentiation. IFN-β is a pro-resolving cytokine well-known as an osteoclast differentiation inhibitor. Here, we explored whether Zol and/or Dex regulate macrophage osteoclastic differentiation via IFN-β. RAW 264.7 and peritoneal macrophages were treated with Zol and/or Dex for 4–24 h, and IFN-β secretion was examined by ELISA, while the IFN stimulated gene (ISG) 15 expression was evaluated by Western blotting. RANKL-induced osteoclastogenesis of RAW 264.7 cells was determined by TRAP staining following treatment with Zol+Dex or IFN-β and anti-IFN-β antibodies. We found only the combination of Zol and Dex increased IFN-β secretion by RAW 264.7 macrophages at 4 h and, correspondingly, ISG15 expression in these cells at 24 h. Moreover, Zol+Dex blocked osteoclast differentiation to a similar extent as recombinant IFN-β. Neutralizing anti-IFN-β antibodies reversed the effect of Zol+Dex on ISG15 expression and partially recovered osteoclastic differentiation induced by each drug alone or in combination. Finally, we found Zol+Dex also induced IFN-β expression in peritoneal resolution phase macrophages, suggesting these drugs might be used to enhance the resolution of acute inflammation. Altogether, our findings suggest Zol+Dex block the differentiation of osteoclasts through the expression of IFN-β. Revealing the molecular pathway behind this regulation may lead to the development of IFN-β-based therapy to inhibit osteoclastogenesis in multiple myeloma patients.

Zoledronate promotes osteoblast differentiation in high-glucose conditions via the p38MAPK pathway

Zoledronate (ZOL) were found to inhibit bone resorption in an animal model of diabetes, high glucose concentrations have been shown to decreased the osteogenesis-related gene expression. But the molecular mechanism by which high glucose levels affect osteoblasts and the effects of ZOL on osteoblast differentiation in a high-glucose environment remain unclear. Therefore, we aimed to investigate the effect of ZOL on osteoblast differentiation in a high-glucose environment and determine the responsible mechanism. Cell proliferation was detected by MTT assay, and cell differentiation was evaluated by immunofluorescence staining for alkaline phosphatase expression, alizarin red staining, cytoskeletal arrangement, and actin fiber formation. Real-time PCR and western blot analyses were performed to detect the mRNA and protein expression of p38MAPK, phosphorylated (p)-p38MAPK, CREB, p-CREB, collagen (COL) I, osteoprotegerin (OPG), and RANKL. The results showed that cell proliferation activity did not differ among the groups. But high glucose inhibited osteoblast differentiation; actin fiber formation; and p38MAPK, p-p38MAPK, CREB, p-CREB, COL I, and OPG expression, while promoting RANKL expression. However, we found that treatment with ZOL reversed these effects of high glucose. And further addition of a p38MAPK inhibitor led to inhibition of osteoblast differentiation and actin fiber formation, and lower p38MAPK, p-p38MAPK, CREB, p-CREB, COL I, and OPG expression than in the high glucose +ZOL group with higher RANKL expression than in the high glucose +ZOL group. Collectively, this study demonstrates that high glucose inhibits the differentiation of osteoblasts, and ZOL could partly overcome these effects by regulating p38MAPK pathway activity.

Dose-dependent effects of pharmaceutical treatments on bone matrix properties in ovariectomized rats

As both anabolic and anti-catabolic osteoporosis drugs affect bone formation and resorption processes, they may contribute to bone's overall mechanical behavior by altering the quality of the bone matrix. We used an ovariectomized rat model and a novel fracture mechanics approach to investigate whether treatment with an anabolic (parathyroid hormone) or anti-catabolic (alendronate) osteoporosis drugs will alter the organic and mineral matrix components and consequently cortical bone fracture toughness. Ovariectomized (at 5 months age) rats were treated with either parathyroid hormone or alendronate at low and high doses for 6 months (age 6–12 months). Specifically, treatment groups included untreated ovariectomized controls (n = 9), high-dose alendronate (n = 10), low-dose alendronate (n = 9), high-dose parathyroid hormone (n = 10), and low-dose parathyroid hormone (n = 9). After euthanasia, cortical microbeams from the lateral quadrant were extracted, notched, and tested in 3-point bending to measure fracture toughness. Portions of the bone were used to measure changes in the 1) organic matrix through quantification of advanced glycation end-products (AGEs) and non-collagenous proteins, and 2) mineral matrix through assessment of mineral crystallinity. Compared to the ovariectomized group, rats treated with high doses of parathyroid hormone and alendronate had significantly increased cortical bone fracture toughness, which corresponded primarily to increased non-collagenous proteins while there was no change in AGEs. Additionally, low-dose PTH treatment increased matrix crystallinity and decreased AGE levels. In summary, ovariectomized rats treated with pharmaceutical drugs had increased non-collagenous matrix proteins and improved fracture toughness compared to controls. Further investigation is required for different doses and longer treatment periods.

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Alendronate increases non-collagenous proteins and improves fracture toughness.

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Parathyroid hormone also increases collagen maturity and mineral crystallinity.

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Both treatments minimize accumulation of advanced glycation end-products.

Role of Fzd6 in Regulating the Osteogenic Differentiation of Adipose-derived Stem Cells in Osteoporotic Mice

OBJECTIVE

Although it has been demonstrated that adipose-derived stem cells (ASCs) from osteoporotic mice (OP-ASCs) exhibited impaired osteogenic differentiation potential, the molecular mechanism has not yet been elucidated. We found that Fzd6 was decreased in OP-ASCs compared with ASCs. This study investigates effects and underlying mechanisms of Fzd6 in the osteogenic potential of OP-ASCs, and explores methods to enhance osteogenic capacity of OP-ASCs.

METHODS

Fzd6 overexpression and silencing lentiviruses were used to evaluate the role of Fzd6 in the osteogenic differentiation of OP-ASCs. Real-time PCR (qPCR) and western blotting (WB) was performed to detect the expression of Fzd6 and bone-related molecules, including runt-related transcription factor 2 (Runx2) and osteopontin (Opn). Alizarin red staining and Alkaline phosphatase (ALP) staining were performed following osteogenic induction. Microscopic CT (Micro-CT), hematoxylin and eosin staining (HE) staining, and Masson staining were used to assess the role of Fzd6 in osteogenic differentiation of osteoporosis (OP) mice in vivo.

RESULTS

Expression of Fzd6 was decreased significantly in OP-ASCs. Fzd6 silencing down-regulated the osteogenic ability of OP-ASCs in vitro. Overexpression of Fzd6 rescued the impaired osteogenic capacity in OP-ASCs in vitro. We obtained similar results in vivo.

CONCLUSIONS

Fzd6 plays an important role in regulating the osteogenic ability of OP-ASCs both in vivo and in vitro. Overexpression of Fzd6 promotes the osteogenic ability of OP-ASCs, which provides new insights for the prevention and treatment of OP mice.

Melatonin promotes bone marrow mesenchymal stem cell osteogenic differentiation and prevents osteoporosis development through modulating circ_0003865 that sponges miR-3653-3p

Background

Little is known about the implications of circRNAs in the effects of melatonin (MEL) on bone marrow mesenchymal stem cell (BMSC) osteogenic differentiation and osteoporosis (OP) progression. The aim of our study was to investigate circRNAs in MEL-regulated BMSC differentiation and OP progression.

Methods

BMSC osteogenic differentiation was measured by qRT-PCR, western blot (WB), Alizarin Red, and alkaline phosphatase (ALP) staining. Differential circRNA and mRNA profiles of BMSCs treated by MEL were characterized by deep sequencing, followed by validation using RT-PCR, Sanger sequencing, and qRT-PCR. Silencing and overexpression of circ_0003865 were conducted for functional investigations. The sponged microRNAs and targeted mRNAs were predicted by bioinformatics and validated by qRT-PCR, RNA pull-down, and dual-luciferase reporter assay. The function of miR-3653-3p and circ_0003865/miR-3653-3p/growth arrest-specific gene 1 (GAS1) cascade was validated for the osteogenic differentiation of BMSCs by CCK-8, qRT-PCR, WB, Alizarin Red, and ALP staining. The effects of circ_0003865 on OP development were tested in murine OP model.

Results

MEL promoted osteogenic differentiation of BMSCs. RNA sequencing revealed significant alterations in circRNA and mRNA profiles associated with multiple biological processes and signaling pathways. Circ_0003865 expression in BMSCs was significantly decreased by MEL treatment. Silencing of circ_0003865 had no effect on proliferation while promoted osteogenic differentiation of BMSCs. Overexpression of circ_0003865 abrogated the promotion of BMSC osteogenic differentiation induced by MEL, but proliferation of BMSCs induced by MEL had no change whether circ_0003865 was overexpression or not. Furthermore, circ_0003865 sponged miR-3653-3p to promote GAS1 expression in BMSCs. BMSC osteogenic differentiation was enhanced by miR-3653-3p overexpression while BMSC proliferation was not affected. By contrast, miR-3653-3p silencing mitigated the promoted BMSC osteogenic differentiation caused by circ_0003865 silencing, but had no effect on proliferation. Finally, circ_0003865 silencing repressed OP development in mouse model.

Conclusion

MEL promotes BMSC osteogenic differentiation and inhibits OP pathogenesis by suppressing the expression of circ_0003865, which regulates GAS1 gene expression via sponging miR-3653-3p.

Influence of Prednisolone and Alendronate on the de novo Mineralization of Zebrafish Caudal Fin

Dysregulated balance between bone resorption and formation mediates the onset and progression of osteoporosis. The administration of prednisolone is known to induce osteoporosis, whereas alendronate is commonly used to reverse the process. However, the assessment of the effects of such medicines on the nanostructure of bone remodeling and mechanical properties remains a major technical challenge. The aim of this study was to apply various analytical approaches to evaluate the compositional, morphological, and mechanical properties of regenerative zebrafish caudal fin bony rays affected by prednisolone and alendronate. Adult wild-type AB strain zebrafish were first exposed to 125μM of prednisolone for 14 days to develop glucocorticoid-induced osteoporosis. Fish fins were then amputated and let to regenerate for 21 days in tank water containing 30μM of alendronate or no alendronate. The lepidotrichia in the proximal and distal regions were evaluated separately using confocal microscope, scanning electron microscope, electron-dispersive spectroscopy, Raman spectroscopy, atomic force microscopy, and a triboindenter. As expected, prednisolone led to significant osteoporotic phenotypes. A decrease of Ca/P ratio was observed in the osteoporotic subjects (1.46 ± 0.04) as compared to the controls (1.74 ± 0.10). Subsequent treatment of alendronate overmineralized the bony rays during regeneration. Enhanced phosphate deposition was detected in the proximal part with alendronate treatment. Moreover, prednisolone attenuated the reduced elastic modulus and hardness levels (5.60 ± 5.04 GPa and 0.12 ± 0.17 GPa, respectively), whereas alendronate recovered them to the pre-amputation condition (8.68 ± 8.74 GPa and 0.34 ± 0.47 GPa, respectively). As an emerging model of osteoporosis, regrowth of zebrafish caudal fin was shown to be a reliable assay system to investigate the various effects of medicines in the de novo mineralization process. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Mechanisms and Molecular Targets of the Tao-Hong-Si-Wu-Tang Formula for Treatment of Osteonecrosis of Femoral Head: A Network Pharmacology Study

The Tao-Hong-Si-Wu-Tang (THSWT) formula, a classic prescription of traditional Chinese medicine, has long been used for the treatment of osteonecrosis of femoral head (ONFH). However, its mechanisms of action and molecular targets are not comprehensively clear. In the present study, the Traditional Chinese Medicine System Pharmacology (TCMSP) database was employed to retrieve the active compounds of each herb included in the THSWT formula. After identifying the drug targets of active compounds and disease targets of ONFH, intersection analysis was conducted to screen out the shared targets. The protein-protein network of the shared targets was built for further topological analysis. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis were then carried out. A gene pathway network was constructed to screen the core target genes. We identified 61 active compounds, 155 drug targets, and 5443 disease targets. However, intersection analysis only screened out 37 shared targets. Kaempferol, luteolin, and baicalein regulated the greatest number of targets associated with ONFH. The THSWT formula may regulate osteocyte function through specific biological processes, including responses to toxic substances and oxidative stress. The regulated pathways included the relaxin, focal adhesion, nuclear factor-κB, toll-like receptor, and AGE/RAGE signaling pathways. RELA, VEGFA, and STAT1 were the important target genes in the gene network associated with the THSWT formula for the treatment of ONFH. Therefore, the present study suggested that the THSWT formula has an action mechanism involving multiple compounds and network targets for the treatment of ONFH.

Systemic osteoprotective effects of Epimedii Folium and Ligustri Lucidi Fructus in senile osteoporosis rats by promoting the osteoblastogenesis and osteoclastogenesis based on MLP-ANN model

Background

Senile osteoporosis (SOP), which is caused by unbalanced bone remodeling, leads to significant economic and societal burdens globally. The combination of Epimedii Folium (EF) and Ligustri Lucidi Fructus (LLF) serves as a commonly-used prescription for SOP in Traditional Chinese Medicine (TCM). This study aimed to evaluate the osteoprotective effects of EF and LLF in combination on SOP rats based on the constructed multilayer perception (MLP)-artificial neural network (ANN) model.

Methods

15 month old male Sprague-Dawley rats were administrated with EF, LLF or the combination of EF and LLF (EF&LLF) for 2 months, while 17 month old rats were used as the aging control group. All the rats were anesthetized with 25% ethyl carbamate, then their serum liver and bone tissues were taken. We detected bone mass, bone mineral density (BMD), biomechanics and the microstructure of bone trabecula by micro-CT and H&E staining to evaluate the degree of osteoporosis. Blood lipids and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ-glutamyl transferase (GGT) and liver pathology were use to assess the side effects of drugs. Levels of alkaline phosphatase (ALP) and Tartrate-resistant acid phosphatase (TRACP) and the ratio of ALP to TRACP both in serum and bone were measured for the evaluation of bone turnover rate. The bone mRNA and protein expression of osteoprotegerin (OPG), nuclear factor-kappa B ligand (RANKL), macrophage colony-stimulating factor (M-CSF), d2 isoform of vacuolar (H⁺) ATPase (ATP6V0d2), insulin-like growth factor (IGF-1), bone morphogenetic protein-2 (BMP2), M-CSF, Wnt5a, transforming growth factor-β1 (TGF-β1) were detected for evaluating bone metabolism.

Results

The results showed that EF&LLF improved bone mass and bone quality by preventing bone loss, increasing maximal load as well as protecting the micro-structural retrogressive change of trabecular bone in SOP rats; ameliorated the steatosis in the liver and decreased blood lipids and serum ALT, AST and GGT; enhanced bone remodeling by stimulating the expression of ALP and TRACP. At the molecular levels, EF&LLF stimulated the osteoclastogenesis by upregulating the protein and mRNA expression of OPG, RANKL, M-CSF and ATP6V0d2; meanwhile, EF&LLF stimulated osteoblastogenesis by enhancing the expression of TGF-β1, BMP2, Wnt5a and IGF-1. According to our established MLP model, EF&LLF has a better effect on osteoclastogenesis or steoblastogenesis in SOP rats than EF or LLF.

Conclusions

These findings demonstrate that the systemic bone protective effects of EF&LLF by promoting bone remodeling in aging rats might be a substitute medicine for the treatment of SOP.

Cancer Nanomedicine Special Issue Review Anticancer Drug Delivery with Nanoparticles: Extracellular Vesicles or Synthetic Nanobeads as Therapeutic Tools for Conventional Treatment or Immunotherapy

Both natural and synthetic nanoparticles have been proposed as drug carriers in cancer treatment, since they can increase drug accumulation in target tissues, optimizing the therapeutic effect. As an example, extracellular vesicles (EV), including exosomes (Exo), can become drug vehicles through endogenous or exogenous loading, amplifying the anticancer effects at the tumor site. In turn, synthetic nanoparticles (NP) can carry therapeutic molecules inside their core, improving solubility and stability, preventing degradation, and controlling their release. In this review, we summarize the recent advances in nanotechnology applied for theranostic use, distinguishing between passive and active targeting of these vehicles. In addition, examples of these models are reported: EV as transporters of conventional anticancer drugs; Exo or NP as carriers of small molecules that induce an anti-tumor immune response. Finally, we focus on two types of nanoparticles used to stimulate an anticancer immune response: Exo carried with A Disintegrin And Metalloprotease-10 inhibitors and NP loaded with aminobisphosphonates. The former would reduce the release of decoy ligands that impair tumor cell recognition, while the latter would activate the peculiar anti-tumor response exerted by γδ T cells, creating a bridge between innate and adaptive immunity.

Effect of bisphosphonate treatment of titanium surfaces on alkaline phosphatase activity in osteoblasts: a systematic review and meta-analysis

Background

Bisphosphonate coating of dental implants is a promising tool for surface modification aiming to improve the osseointegration process and clinical outcome. The biological effects of bisphosphonates are thought to be mainly associated with osteoclasts inhibition, whereas their effects on osteoblast function are unclear. A potential of bisphosphonate coated surfaces to stimulate osteoblast differentiation was investigated by several in vitro studies with contradictory results. The purpose of this systematic review and meta-analysis was to evaluate the effect of bisphosphonate coated implant surfaces on alkaline phosphatase activity in osteoblasts.

Methods

In vitro studies that assessed alkaline phosphatase activity in osteoblasts following cell culture on bisphosphonate coated titanium surfaces were searched in electronic databases PubMed/MEDLINE, Scopus and ISI Web of Science. Animal studies and clinical trials were excluded. The literature search was restricted to articles written in English and published up to August 2019. Publication bias was assessed by the construction of funnel plots.

Results

Eleven studies met the inclusion criteria. Meta-analysis showed that coating of titanium surfaces with bisphosphonates increases alkaline phosphatase activity in osteoblasts after 3 days (n = 1), 7 (n = 7), 14 (n = 6) and 21 (n = 3) days. (7 days beta coefficient = 1.363, p-value = 0.001; 14 days beta coefficient = 1.325, p-value < 0.001; 21 days beta coefficient = 1.152, p-value = 0.159).

Conclusions

The meta-analysis suggests that bisphosphonate coatings of titanium implant surfaces may have beneficial effects on osteogenic behaviour of osteoblasts grown on titanium surfaces in vitro. Further studies are required to assess to which extent bisphosphonates coating might improve osseointegration in clinical situations.

Lycopene and bone: an in vitro investigation and a pilot prospective clinical study

Background

There are several effective therapies for osteoporosis but these agents might cause serious adverse events. Lycopene intake could prevent bone loss, however studies on its effects on bone are scarce. Our aim was to investigate the effects of lycopene on osteoblast cells as well as bone mineral density and bone turnover markers in postmenopausal women.

Methods

We investigated the effect of lycopene on the Wnt/β-catenin and ERK 1/2 pathways, RUNX2, alkaline phosphatase, RANKL and COL1A of Saos-2. We also carried out a pilot controlled clinical study to verify the feasibility of an approach for bone loss prevention through the intake of a lycopene-rich tomato sauce in 39 postmenopausal women.

Results

Lycopene 10 µM resulted in higher β-catenin and phERK1/2 protein Vs the vehicle (p = 0.04 and p = 0.006). RUNX2 and COL1A mRNA was induced by both 5 and 10 µM doses (p = 0.03; p = 0.03 and p = 0.03; p = 0.05) while RANKL mRNA was reduced (p < 0.05). A significant bone density loss was not detected in women taking the tomato sauce while the control group had bone loss (p = 0.002). Tomato sauce intake resulted in a greater bone alkaline phosphatase reduction than the control (18% vs 8.5%, p = 0.03).

Conclusions

Lycopene activates the WNT/β-catenin and ERK1/2 pathways, upregulates RUNX2, alkaline phosphatase, COL1A and downregulates RANKL Saos-2. These processes contributed to prevent bone loss in postmenopausal women.

Melatonin Reverses the Loss of Stemness Induced by TNF-α in Human Bone Marrow Mesenchymal Stem Cells through Upregulation of YAP Expression

Mesenchymal stem cells (MSCs) are promising candidates for tissue regeneration and disease treatment. However, long-term in vitro culture results in loss of MSC stemness. The inflammation that occurs at stem cell transplant sites (such as that resulting from TNF-α) is a contributing factor for stem cell treatment failure. Currently, there is little evidence regarding the protective role of melatonin with regard to the negative effects of TNF-α on the stemness of MSCs. In this study, we report a melatonin-based method to reduce the inflammatory effects on the stemness of bone marrow mesenchymal stem cells (BMMSCs). The results of colony formation assays, Alizarin red staining, western blotting, and reverse transcription-polymerase chain reactions suggest that melatonin can reverse the inflammatory damage caused by TNF-α treatment in the third, seventh, and tenth generations of primary BMMSCs (vs. control and the TNF-α-treated group). Meanwhile, a detailed analysis of the molecular mechanisms showed that the melatonin receptor and YAP signaling pathway are closely related to the role that melatonin plays in negative inflammatory effects against BMMSCs. In addition, in vivo experiments showed that melatonin could reverse the damage caused by TNF-α on bone regeneration by BMMSCs in nude mice. Overall, our results suggest that melatonin can reverse the loss of stemness caused by inflammatory factor TNF-α in BMMSCs. Our results also provide a practical strategy for the application of BMMSCs in tissue engineering and cell therapy.

Effect of Plastrum Testudinis Extracts on the Proliferation and Osteogenic Differentiation of rBMSCs by Regulating p38 MAPK-Related Genes

Extracts from plastrum testudinis (PTE) are active compounds that have been used to treat bone diseases in traditional Chinese medicine for thousands of years. In previous studies, we demonstrated their effects on glucocorticoid-induced osteoporosis both in vivo and in vitro. However, the mechanisms by which PTE regulates the osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (rBMSCs) in vitro remain poorly understood. In this study, rBMSCs were treated with medium (CON), PTE, osteogenic induction (OI), and a combination of PTE and OI (PTE+OI) over a 21-day period. We found that PTE significantly promoted rBMSCs osteogenic differentiation and mineralisation after 21 days of culturing. Moreover, PTE+OI further enhanced the differentiation and mineralisation process. PTE upregulated STE20, IGF1R, and p38 MAPK mRNA expression and downregulated TRAF6 mRNA expression. The extracts inhibited TRAF6 protein expression and promoted STE20, IGF1R, and phosphorylated p38 MAPK protein expression. Our results imply that PTE promotes the proliferation and osteogenic differentiation of rBMSCs by upregulating p38 MAPK, STE20, and IGF1R and downregulating TRAF6 expression, which may provide experimental evidence of the potential of PTE in the treatment of osteoporosis.

Zebrafish as an Emerging Model for Osteoporosis: A Primary Testing Platform for Screening New Osteo-Active Compounds

Osteoporosis is metabolic bone disease caused by an altered balance between bone anabolism and catabolism. This dysregulated balance is responsible for fragile bones that fracture easily after minor falls. With an aging population, the incidence is rising and as yet pharmaceutical options to restore this imbalance is limited, especially stimulating osteoblast bone-building activity. Excitingly, output from large genetic studies on people with high bone mass (HBM) cases and genome wide association studies (GWAS) on the population, yielded new insights into pathways containing osteo-anabolic players that have potential for drug target development. However, a bottleneck in development of new treatments targeting these putative osteo-anabolic genes is the lack of animal models for rapid and affordable testing to generate functional data and that simultaneously can be used as a compound testing platform. Zebrafish, a small teleost fish, are increasingly used in functional genomics and drug screening assays which resulted in new treatments in the clinic for other diseases. In this review we outline the zebrafish as a powerful model for osteoporosis research to validate potential therapeutic candidates, describe the tools and assays that can be used to study bone homeostasis, and affordable (semi-)high-throughput compound testing.