Berberine Sulfate Attenuates Osteoclast Differentiation through RANKL Induced NF-κB and NFAT Pathways

Chitosan/alginate scaffold enhanced with Berberis vulgaris extract for osteocyte differentiation of ovine fetal stem cells

Designing biocompatible polymers using plant derivatives can be extremely useful in tissue engineering, nanomedicine, and many other fields of medicine. In this study, it was first looked into how chitosan/alginate scaffolds were made and characterized in the presence of berberine and barberry fruit extract. Second, the process of proliferation and differentiation of ovine fetal BM-MSCs (bone marrow-mesenchymal stem cells) was assessed on these scaffolds after BM-MSCs were extracted and confirmed by developing into osteocyte and adipose cells. To investigate the differentiation, treatment groups include (1) ovine fetal BM-MSCs were plated in Dulbecco's modified eagle medium culture medium with high glucose containing 10% fetal bovine serum and antibiotics (negative control), (2) ovine fetal BM-MSCs were plated in osteogenic differentiation medium (positive control group), (3) positive control group + barberry fruit extract, (4) positive control group + berberine, (5) ovine fetal BM-MSCs were plated in osteogenic differentiation medium on chitosan/alginate scaffold (hydrogel group), (6) ovine fetal BM-MSCs were plated in osteogenic differentiation medium on chitosan/alginate/barberry fruit extract scaffold (hydrogel group containing barberry fruit extract), and (7) ovine fetal BM-MSCs were plated in osteogenic differentiation medium on chitosan/alginate/berberine scaffold (hydrogel group containing berberine). Alkaline phosphatase (ALP) enzyme concentrations, mineralization rate using a calcium kit, and mineralization measurement by alizarin staining quantification were all found after 21 days of culture. In addition, real-time quantitative reverse transcription polymerase chain reaction was used to assess the expression of the ALP, COL1A2, and Runx2 genes. Days 5 and 7 had the lowest water absorption by the hydrogel scaffold containing barberry extract, which was significant in comparison to other groups (p < .05). Among the hydrogel scaffolds under study, the one containing barberry extract exhibited the lowest tensile strength, and this difference was statistically significant (p < .05). The chitosan/alginate hydrogel has the highest tensile strength of all of them. In comparison to the control and other treatment groups, the inclusion of berberine in the chitosan/alginate hydrogel significantly increased the expression of the ALP, Runx2, and COL1A2 genes (p < .05). The osteocyte differentiation of mesenchymal stem cells in in vitro settings appears to have been enhanced by the inclusion of berberine in the chitosan/alginate scaffold.

Assessment of Anti-Arthritic Activity of Lipid Matrix Encased Berberine in Rheumatic Animal Model

AIM

The purpose of this study was to evaluate the drug delivery and therapeutic potential of berberine (Br) loaded nanoformulation in rheumatoid arthritis (RA)-induced animal model.

METHOD

The Br-loaded NLCs (nanostructured lipid carriers) were prepared employing melt-emulsification process, and optimized through box-behnken design. The prepared NLCs were assessed for in-vitro and in-vivo evaluations.

RESULT

The optimized NLCs exhibited a mean diameter of 180.2 ± 0.31nm with 88.32 ± 2.43% entrapment efficiency. An enhanced anti-arthritic activity with reduced arthritic scores to 0.66 ± 0.51, reduction in ankle diameter to 5.80 ± 0.27mm, decline in paw withdrawal timing, and improvements in walking behavior were observed in the Br-NLCs treated group. The radiographic images revealed a reduction in bone and cartilage deformation.

CONCLUSION

The Br-NLCs showed promising results in the management of RA disease, can be developed as an efficient delivery system at commercial levels, and may be explored for clinical application after suitable experiments in the future.

Phosphatidyl Inositol 3-Kinase (PI3K)-Inhibitor CDZ173 protects against LPS-induced osteolysis

A major complication of a joint replacement is prosthesis loosening caused by inflammatory osteolysis, leading to the revision of the operation. This is due to the abnormal activation of osteoclast differentiation and function caused by periprosthetic infection. Therefore, targeting abnormally activated osteoclasts is still effective for treating osteolytic inflammatory diseases. CDZ173 is a selective PI3K inhibitor widely used in autoimmune-related diseases and inflammatory diseases and is currently under clinical development. However, the role and mechanism of CDZ173 in osteoclast-related bone metabolism remain unclear. The possibility for treating aseptic prosthesis loosening brought on by inflammatory osteolysis illness can be assessed using an LPS-induced mouse cranial calcium osteolysis model. In this study, we report for the first time that CDZ173 has a protective effect on LPS-induced osteolysis. The data show that this protective effect is due to CDZ173 inhibiting the activation of osteoclasts in vivo. Meanwhile, our result demonstrated that CDZ173 had a significant inhibitory effect on RANKL-induced osteoclasts. Furthermore, using the hydroxyapatite resorption pit assay and podosol actin belt staining, respectively, the inhibitory impact of CDZ173 on bone resorption and osteoclast fusion of pre-OC was determined. In addition, staining with alkaline phosphatase (ALP) and alizarin red (AR) revealed that CDZ173 had no effect on osteoblast development in vitro. Lastly, CDZ173 inhibited the differentiation and function of osteoclasts by weakening the signal axis of PI3K-AKT/MAPK-NFATc1 in osteoclasts. In conclusion, our results highlight the potential pharmacological role of CDZ173 in preventing osteoclast-mediated inflammatory osteolysis and its potential clinical application.

Specnuezhenide suppresses diabetes-induced bone loss by inhibiting RANKL-induced osteoclastogenesis

Diabetes osteoporosis is a chronic complication of diabetes mellitus (DM) and is associated with osteoclast formation and enhanced bone resorption. Specnuezhenide (SPN) is an active compound with anti-inflammatory and immunomodulatory properties. However, the roles of SPN in diabetic osteoporosis remain unknown. In this study, primary bone marrow macrophages (BMMs) were pretreated with SPN and were stimulated with receptor activator of nuclear factor kappa B ligand (RANKL; 50 ng/mL) to induce osteoclastogenesis. The number of osteoclasts was detected by tartrate-resistant acid phosphatase (TRAP) staining. The protein levels of cellular oncogene fos/nuclear factor of activated T cells c1 (c-Fos/NFATc1), nuclear factor kappa-B (NF-κB), and mitogen-activated protein kinases (MAPKs) were evaluated by western blot analysis. NF-κB luciferase assays were used to examine the role of SPN in NF-κB activation. The DM model group received a high-glucose, high-fat diet and was then intraperitoneally injected with streptozotocin (STZ). Micro-CT scanning, serum biochemical analysis, histological analysis were used to assess bone loss. We found that SPN suppressed RANKL-induced osteoclast formation and that SPN inhibited the expression of osteoclast-related genes and c-Fos/ NFATc1. SPN inhibited RANKL-induced activation of NF-κB and MAPKs. In vivo experiments revealed that SPN suppressed diabetes-induced bone loss and the number of osteoclasts. Furthermore, SPN decreased the levels of bone turnover markers and increased the levels of runt-related transcription factor 2 (RUNX2), osteoprotegerin (OPG), calcium (Ca) and phosphorus (P). SPN also regulated diabetes-related markers. This study suggests that SPN suppresses diabetes-induced bone loss by inhibiting RANKL-induced osteoclastogenesis, and provides an experimental basis for the treatment of diabetic osteoporosis.

Therapeutic Potential of Berberine for Osteoporosis and its Underlying Mechanisms: A Bioinformatics, Network Pharmacology, Molecular Dynamics Simulation Study

Osteoporosis is a systemic skeletal disease that can easily lead to bone fractures. Berberine has been shown to be effective in treating osteoporosis. This study was conducted to identify the potential mechanism of berberine in treating this complaint. We screened potential targets of berberine and identified the osteoporosis-related differentially expressed genes (DEGs) in the microarray dataset GSE56815. Protein–protein interaction (PPI) network construction, hub targets identification, and pathway enrichment were carried out to find the potential targets. Molecular docking and molecular dynamics studies were performed to verify the combination of berberine with its treatment-related central targets. In addition, SwissADME preliminarily evaluated the physicochemical properties of berberine. Through data mining, 23 osteoporosis-related targets of berberine were selected. PPI and module analyses suggested that AKT1, MAPK1, ESR1, AR, TP53, and PTGS2 are the core targets of berberine. Docking and molecular dynamics studies showed that berberine could stably bind to core proteins to form a protein–ligand complex. The enrichment analysis showed that the estrogen signaling pathway and thyroid hormone signaling pathway play important roles in curing osteoporosis. To sum up, berberine primarily acts on AKT1, MAPK1, ESR1, AR, TP53, and PTGS2, mainly regulating the estrogen and thyroid hormone signaling pathways to treat osteoporosis in a multi-target, multi-pathway, and multi-system manner.

Cellulose Acetate Nanofibers: Incorporating Hydroxyapatite (HA), HA/Berberine or HA/Moghat Composites, as Scaffolds to Enhance In Vitro Osteoporotic Bone Regeneration

The specific objective of this study was to stabilize a simple valid method to prepare pure nanorod hydroxyapatite (HA) mixed with berberine chloride (BER) and Moghat water extract (ME) as composites for incorporation into cellulose acetate (CA) nanofibers to be used as novel bone scaffolds and to determine their efficacy in bone regeneration process In Vitro. Preparation of HA/BER and HA/ME composites were performed by mixing powders using the ball-milling machine. The HA, HA/BER, and HA/ME composites at a concentration of 6.25, 12.5, 25, 50, 100, and 200 mg were mixed with CA solution (13%), then the fiber was formed using electrospinning technique. The properties of the obtained CA fibers were investigated (SEM, TEM, EDX, FTIR, TGA, water uptake, porosity, and mechanical tests). The efficacy of HA and HA composites loaded into CA nanofiber on osteoblast and osteoclast differentiation were measured by tacking ALP, osteocalcin, TRAcP, calcium, and total protein concentration. Moreover, their effects on cell differentiation (CD90 and PARP- ɣ) and death markers (GSK3b, MAPK, Wnt-5 and β-catenin) were evaluated by using ELISA and qPCR. The obtained TEM results indicated that the continuous CA and CA/HA composites electrospun fibers have ultrafine fiber diameters of about 200 nm and uniform distribution of discrete n-HA clusters throughout. In addition, hydrocortisone (HCT) was found to increase the formation of adipocytes and osteoclastic markers CD90 and p38-MAPK which indicated the bone lose process take placed. Treatment with CA loaded with HA, HA/BER or HA/ME decreased CD90, Wnt-5, PARP- ɣ, GSK3b and p38-MAPK associated elevation of osteogenic markers: ALP and osteocalcin. Moreover, HCT overexpressed RANKL and down expressed Osterix gene. Treatment with CA/HA/BER or CA/HA/ME downregulated RANKL and upregulated Osterix associated with a reduction in RANKL/OPG ratio, at p < 0.05. In conclusion, novel CA composite nanofibers (CA/HA/BER and CA/HA/ME) reversed the HCT adverse effect on osteoblast cell death through canonical and non-canonical pathways regulated by Wnt/β-catenin and Wnt/Ca(²⁺) pathways. Furthermore, our data confirmed that the novel scaffolds create a crosstalk between RUNX-2, RANKL, p38-MAPK, and Wnt signals which positively impact bone regeneration process. Treatment with CA/HA/BER is better compared to the treatment with CA/HA/ME. Nevertheless, both are considered as alternative biomaterial scaffolds with a potential for biomedical applications in the field of bone tissue engineering.

Hormesis and bone marrow stem cells: Enhancing cell proliferation, differentiation and resilience to inflammatory stress

This paper identifies and provides the first detailed assessment of hormetic dose responses by bone marrow stem cells (BMSCs) from a broad range of animal models and humans with particular emphasis on cell renewal (proliferation), cell differentiation and enhancing resilience to inflammatory stress. Such hormetic dose responses are commonly reported, being induced by a broad range of chemicals, including pharmaceuticals (e.g., caffeine, dexamethasone, nicotine), dietary supplements (e.g., curcumin, Ginkgo biloba, green tea extracts. resveratrol, sulforaphane), endogenous agents (e.g., hydrogen sulfide, interleukin 10), environmental contaminants (e.g., arsenic, PFOS) and physical stressor agents (e.g., EMF, shockwaves). Hormetic dose responses reported here for BMSCs are similar to those induced with other stem cell types [e.g., adipose-derived stem cells (ADSCs), dental pulp stem cells (DPSCs), periodontal ligament stem cells (PDLSCs), neuro stem cells (NSCs), embryonic stem cells (ESCs)], indicating a substantial degree of generality for hormetic responses in stem cells. The paper assesses both the underlying mechanistic foundations of BMSC hormetic responses and their potential therapeutic implications.

Berberine for bone regeneration: Therapeutic potential and molecular mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

Berberine is a quaternary ammonium isoquinoline alkaloid, mainly extracted from plants berberaceae, papaveraceae, ranunculaceae and rutaceae such as coptis chinensis Franch, Phellodendron chinense, and berberis pruinosa. The plants are extensively used in traditional medicine for treating infection, diabetes, arrhythmia, tumor, osteoporosis et al. Pharmacological studies showed berberine has effects of anti-inflammation, anti-tumor, lower blood lipid, lower blood glucose, anti-osteoporosis, anti-osteoarthritis et al. AIM OF THE STUDY: This review aims to summarize the application of natural herbs that contain berberine, the further use and development of berberine, the effects as well as mechanism of berberine on osteoblasts and osteoclasts, the recent advances of in vivo studies, in order to provide a scientific basis for its traditional uses and to prospect of the potential applications of berberine in clinics.

METHOD

The research was achieved by retrieving from the online electronic database, including PubMed, Web of Science, Google Scholar and China national knowledge infrastructure (CNKI). Patents, doctoral dissertations and master dissertations are also searched.

RESULTS

Berberine has a long history of medicinal use to treat various diseases including bone disease in China. Recent studies have defined its function in promoting bone regeneration and great potential in developing new drugs. But the systemic mechanism of berberine on bone regeneration still needs more research to clarify.

CONCLUSION

This review has systematically summarized the application, pharmacological effects, mechanism as well as in vivo studies of berberine and herbs which contain berberine. Berberine has a definite effect in promoting the proliferation and differentiation of osteoblasts as well as inhibiting the production of osteoclasts to promote bone regeneration. However, the present studies about the system mechanisms and pharmacological activity of berberine were incomplete. Applying berberine for new drug development remains an exciting and promising alternative to bone regeneration engineering, with broad potential for therapeutic and clinical practice.

Phospholipase Cγ Signaling in Bone Marrow Stem Cell and Relevant Natural Compounds Therapy

Excessive bone resorption has been recognized play a major role in the development of bone-related diseases such as osteoporosis, rheumatoid arthritis, Paget's disease of bone, and cancer. Phospholipase Cγ (PLCγ) family members PLCγ1 and PLCγ2 are critical regulators of signaling pathways downstream of growth factor receptors, integrins, and immune complexes and play a crucial role in osteoclast. Ca2+ signaling has been recognized as an essential pathway to the differentiation of osteoclasts. With growing attention and research about natural occurring compounds, the therapeutic use of natural active plant-derived products has been widely recognized in recent years. In this review, we summarized the recent research on PLCγ signaling in bone marrow stem cells and the use of several natural compounds that were proven to inhibit RANKL-mediated osteoclastogenesis via modulating PLCγ signaling pathways.

Effect of Orento, a Traditional Japanese Medicine, on IL-6, IL-8 Secretion, Type 1 Collagen Production and Alkaline Phosphatase Secretion in the Human Osteosarcoma Cell Line Saos-2

Background: Orento, a traditional Japanese medicine, is known as Kampo medicine in Japan. We investigated the possible efficacy of Kampo medicine for periodontal disease. In this study, we examined the in vitro effects of orento on the proliferation of the inflammatory cytokines interleukin (IL)-6 and IL-8, the production of type 1 collagen, and the secretion of alkaline phosphatase (ALP) in the human osteosarcoma cell line Saos-2 (Saos-2 cells). Methods: The proliferation of Saos-2 cells was assessed by MTT assay. IL-6 and IL-8 levels, type 1 collagen production and ALP secretion were evaluated using enzyme-linked immunosorbent assay and ALP assays. Saos-2 cells were treated with or without 0.1, 1, 10, 100 and 1000 μg/mL of orento for 24 h. Results: Orento (10 μg/mL) significantly induced the proliferation of Saos-2 cells. At this concentration, orento suppressed IL-6 and IL-8 and enhanced type 1 collagen production and ALP secretion. Conclusions: These results indicate that orento controls the IL-6 and IL-8 secretion and cellular metabolism of osteoblasts, resulting in the secretion of early bone-related biomarkers.

Goldenseal (Hydrastis canadensis L.) and its active constituents: A critical review of their efficacy and toxicological issues

Goldenseal (Hydrastis canadensis L.) is a medicinal plant widely used in various traditional systems of medicine and as a food supplement. It has been traditionally used by Native Americans as a coloring agent and as medicinal remedy for common diseases and conditions like wounds, digestive disorders, ulcers, skin and eye ailments, and cancer. Over the years, goldenseal has become a popular food supplement in the USA and other regions. The rhizome of this plant has been used for the treatment of a variety of diseases including, gastrointestinal disorders, ulcers, muscular debility, nervous prostration, constipation, skin and eye infections, cancer, among others. Berberine is one of the most bioactive alkaloid that has been identified in different parts of goldenseal. The goldenseal extract containing berberine showed numerous therapeutic effects such as antimicrobial, anti-inflammatory, hypolipidemic, hypoglycemic, antioxidant, neuroprotective (anti-Alzheimer's disease), cardioprotective, and gastrointestinal protective. Various research finding suggest the health promoting effects of goldenseal components and their extracts. However, few studies have also suggested the possible neurotoxic, hepatotoxic and phototoxic activities of goldenseal extract and its alkaloids. Thus, large randomized, double-blind clinical studies need to be conducted on goldenseal supplements and their main alkaloids to provide more evidence on the mechanisms responsible for the pharmaceutical activity, clinical efficacy and safety of these products. Thus, it is very important to review the scientific information about goldenseal to understand about the current scenario.

Berberine and musculoskeletal disorders: The therapeutic potential and underlying molecular mechanisms

BACKGROUND

Musculoskeletal disorders are a group of disorders that affect the joints, bones, and muscles, causing long-term disability. Berberine, an isoquinoline alkaloid, has been previously established to exhibit beneficial properties in preventing various diseases, including musculoskeletal disorders.

PURPOSE

This review article aims to recapitulate the therapeutic potential of berberine and its mechanism of action in treating musculoskeletal disorders.

METHODS

A wide range of literature illustrating the effects of berberine in ameliorating musculoskeletal disorders was retrieved from online electronic databases (PubMed and Medline) and reviewed.

RESULTS

Berberine may potentially retard the progression of osteoporosis, osteoarthritis and rheumatoid arthritis. Limited studies reported the effects of berberine in suppressing the proliferation of osteosarcoma cells. These beneficial properties of berberine are mediated in part through its ability to target multiple signaling pathways, including PKA, p38 MAPK, Wnt/β-catenin, AMPK, RANK/RANKL/OPG, PI3K/Akt, NFAT, NF-κB, Hedgehog, and oxidative stress signaling. In addition, berberine exhibited anti-apoptotic, anti-inflammatory, and immunosuppressive properties.

CONCLUSION

The current evidence indicates that berberine may be effective in preventing musculoskeletal disorders. However, findings from in vitro and in vivo investigations await further validation from human clinical trial.

Cytoplasmic PCNA is located in the actin belt and involved in osteoclast differentiation

Osteoporosis (OP) is an age-related osteolytic disease and characterized by low bone mass and more prone to fracture due to active osteoclasts. Proliferating cell nuclear antigen (PCNA) has been long identified as a nuclear protein playing critical roles in the regulation of DNA replication and repair. Recently, a few studies have demonstrated the cytoplasmic localization of PCNA and its function associated with apoptosis in neutrophil and neuroblastoma cells. However, the involvement of PCNA, including the cytoplasmic PCNA, in the osteoclast differentiation remains unclear. In the present study, we show that PCNA is translocated from nucleus to cytoplasm during the RANKL-induced osteoclast differentiation, and localized in the actin belt of mature osteoclast. Knockdown of PCNA significantly affected the integrity of actin belt, the formation of multinucleated osteoclasts, the expression of osteoclast-specific genes, and the in vitro bone resorption. Interactomic study has revealed β-actin as the major interacting partner of the cytoplasmic PCNA, suggesting that cytoplasmic PCNA might play a critical role in the differentiation of osteoclast through regulation of actin-cytoskeleton remodeling. Taken together, our results demonstrate the critical role of cytoplasmic PCNA during the process of osteoclast differentiation, and provided a potential therapeutic target for treatment of osteoclast-related bone diseases.

Discovery and development of berberine derivatives as stimulants of osteoblast differentiation

Berberine is an essential phytochemical for the treatment of various diseases; however, when used to treat osteoporosis, it has minor effect as compared with that of the currently available drugs. This study aimed to find a new compound that would have a better anti-osteoporotic effect than that of berberine. Based on structure and activity relationship study, we identified compound 2c, a berberine derivative, to be the most potent compound to affect osteoblast differentiation. Compound 2c was more effective than berberine and exhibited no toxicity within its effective concentration. Compound 2c increased, in a dose-dependent manner, ALP activity during osteoblast differentiation and enhanced the mRNA expression of osteogenic factors including ALP, Runx2, and Osterix. Furthermore, compound 2c increased the transcriptional activity induced by BMP4 on the ALP and BSP promoter. Taken together, compound 2c shows promise as a therapeutic agent for osteoporosis by promoting osteoblast differentiation.

Tubeimoside I suppresses diabetes-induced bone loss in rats, osteoclast formation, and RANKL-induced nuclear factor-κB pathway

Type 2 diabetes mellitus is often companied with osteoporosis, a process which involves osteoclast activation. In this study, we found tubeimoside I, a natural compound isolated from the Chinese medicinal herb Bolbostemma paniculatum (Maxim) Franquet (Cucurbitaceae), significantly ameliorated the decrease of bone mass in type 2 diabetes-induced osteoporosis in rats. It appears that tubeimoside I exerts this protecting effect through inhibiting osteoclast formation and function. Futhermore, our study showed that tubeimoside I inhibits NF-κB transcriptional activation and degradation of IκBα. Collectively, our results reveal that tubeimoside I attenuates osteoclastogenesis through down-regulating NF-κB signaling pathway, and is a potential candidate for the treatment of bone-destructive diseases like type 2 diabetic osteoporosis.

Asperpyrone A attenuates RANKL-induced osteoclast formation through inhibiting NFATc1, Ca2+ signalling and oxidative stress

Imbalance of osteoblast and osteoclast in adult leads to a variety of bone-related diseases, including osteoporosis. Thus, suppressing the activity of osteoclastic bone resorption becomes the main therapeutic strategy for osteoporosis. Asperpyrone A is a natural compound isolated from Aspergillus niger with various biological activities of antitumour, antimicrobial and antioxidant. The present study was designed to investigate the effects of Asperpyrone A on osteoclastogenesis and to explore its underlining mechanism. We found that Asperpyrone A inhibited RANKL-induced osteoclastogenesis in a dose-dependent manner when the concentration reached 1 µm, and with no cytotoxicity until the concentration reached to 10 µm. In addition, Asperpyrone A down-regulated the mRNA and protein expression of NFATc1, c-fos and V-ATPase-d2, as well as the mRNA expression of TRAcP and Ctsk. Furthermore, Asperpyrone A strongly attenuated the RNAKL-induced intracellular Ca2+ oscillations and ROS (reactive oxygen species) production in the process of osteoclastogenesis and suppressed the activation of MAPK and NF-κB signalling pathways. Collectively, Asperpyrone A attenuates RANKL-induced osteoclast formation via suppressing NFATc1, Ca2+ signalling and oxidative stress, as well as MAPK and NF-κB signalling pathways, indicating that this compound may become a potential candidate drug for the prevention or treatment of osteoporosis.

Microtubule actin crosslinking factor 1 (MACF1) knockdown inhibits RANKL-induced osteoclastogenesis via Akt/GSK3β/NFATc1 signalling pathway

Osteoclasts are responsible for bone resorption and play essential roles in causing bone diseases such as osteoporosis. Microtubule actin crosslinking factor 1 (MACF1) is a large spectraplakin protein that has been implicated in regulating cytoskeletal distribution, cell migration, cell survival and cell differentiation. However, whether MACF1 regulates the differentiation of osteoclasts has not been elucidated. In this study, we found that the expression of MACF1 was increased in primary bone marrow-derived monocytes (BMMs) of osteoporotic mice and was downregulated during receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclastogenesis of pre-osteoclast cell lines RAW264.7 cells. RAW264.7 cells were transfected with shMACF1 using a lentiviral vector to study the role of MACF1 in osteoclastogenic differentiation. Knockdown of MACF1 in RAW264.7 cells inhibited the formation of multinucleated osteoclasts and decreased the expression of osteoclast-marker genes (Ctsk, Acp5, Mmp9 and Oscar) during RANKL-induced osteoclastogenesis. Additionally, knockdown of MACF1 disrupted actin ring formation in osteoclasts and further blocked the bone resorption activity of osteoclasts by reducing the area and depth of pits. Knockdown of MACF1 had no effect on the survival of pre-osteoclasts and mature osteoclasts. We further established that knockdown of MACF1 attenuated the phosphorylation of Akt and GSK3β and inhibited the expression of its downstream target NFATc1. Akt activator rescued the inhibition of osteoclast differentiation by MACF1 knockdown. These data demonstrate that MACF1 positively regulates osteoclast differentiation via the Akt/GSK3β/NFATc1 signalling pathway, suggesting that targeting MACF1 may be a novel therapeutic approach against osteoporosis.

Berberine Suppresses RANKL-Induced Osteoclast Differentiation by Inhibiting c-Fos and NFATc1 Expression

Osteoporosis is a common disorder of bone remodeling, marked by excessive osteoclast formation. Recent studies indicated that berberine (BBR) is a potential natural drug for the treatment of various bone diseases. However, it still needs to be further studied for the treatment of osteoporosis. The current study investigated the inhibitory effects of BBR on receptor activator of nuclear factor- κ B ligand (RANKL)-induced osteoclast differentiation in vitro and in vivo. Cell-based assays were performed using osteoclasts generated in cultures of murine bone marrow-derived macrophages (BMMs) treated with RANKL and M-CSF. The effects of BBR on in vivo lipopolysaccharide (LPS)-mediated bone loss were evaluated using ICR mice. BBR significantly inhibited TRAP-positive osteoclast formation induced by RANKL. BBR also inhibited RANKL-induced Akt, p38 and ERK phosphorylation and I κ B degradation, and suppressed RANKL-induced expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which is a key transcription factors for osteoclast formation. BBR reduced the mRNA levels of osteoclast markers, including TRAP, osteoclast-associated receptor (OSCAR), cathepsin K, and ATPase H + transporting V0 subunit d2 (ATP6v0d2). Moreover, BBR prevented LPS-mediated bone loss in vivo. We suggest BBR as a natural compound that can be a potential therapeutic agent for osteoclast-related bone diseases.

Berberine promotes osteogenic differentiation of mesenchymal stem cells with therapeutic potential in periodontal regeneration

Periodontal disease is a bacterial infection-associated disease of the periodontal tissues characterized by the destruction of tooth-supporting structures, including alveolar bone. The ideal goal of periodontal therapy is the complete regeneration of alveolar bone in a healthy microenvironment free of infection. In this study, we found that berberine, a benzylisoquinoline plant alkaloid from Coptidis Rhizoma, strongly inhibited the growth of Porphyromonas gingivalis. Gingipain is the most important virulence factor of Porphyromonas gingivalis in the process of periodontal tissue destruction. Berberine also had an inhibitory effect on gingipain activity in a concentration dependent manner. Remarkably, berberine restored the downregulation of osteogenesis-related genes expression in bone mesenchymal stem cells (BMSCs) induced by Porphyromonas gingivalis infection, and significantly increased the expression of osteogenesis-related genes such as OSX, COLI, ALP, OCN and OPN compared to the control group. This results suggested that berberine may directly promote osteogenesis. Further in-vitro studies demonstrated that berberine statistically significantly promoted the osteogenic differentiation of BMSCs at concentrations of 1-10 μM. In the research on the mechanisms, we found that both total β-catenin and nuclear β-catenin accumulation were statistically significantly increased by berberine. And the transcriptional activity of β-catenin/TCF was about 2 folds higher than the control group. Furthermore, Wnt signalling specific inhibitor DKK-1 blocked the above effects of berberine. These demonstrated that Wnt/β-catenin signalling pathway was involved in the osteogenic differentiation induced by berberine. The antibacterial actions in combination with the promotion role in osteogenic differentiation position berberine as a prospective drug for periodontal tissue regeneration.

FNDC4 Inhibits RANKL-Induced Osteoclast Formation by Suppressing NF-κB Activation and CXCL10 Expression

FNDC4 acts as an anti-inflammatory factor on macrophages and improves mouse model of induced colitis. Considering osteoclast formation is characterized by the activation of inflammation-related pathways, we thus speculated that FNDC4 may play a pivotal role in this process. RT-qPCR analysis was performed to confirm the expression of osteoclast formation related genes in primary murine bone marrow macrophages (BMMs). RANKL-treated BMMs were cultured with FNDC4 to evaluate the effect of FNDC4 on osteoclast differentiation. TRAP staining and bone resorption pits assay were used to assess osteoclast formation and bone resorption, respectively. Luciferase assay and western blotting analysis were conducted to determine whether FNDC4 inhibited osteoclast formation via NF-κB signaling in RAW 264.7 cells. Furthermore, to identify gene signatures in FNDC4-treated BMMs and to use these to elucidate the underlying molecular mechanisms during osteoclast formation, we adopted a bioinformatics approach by downloading the GSE76172 gene expression profiling dataset from the Gene Expression Omnibus (GEO) database. FNDC4 inhibited RANKL-induced osteoclastogenesis and mature osteoclast resorptive function in a dose-dependent manner. Results of NF-κB luciferase assay suggested that FNDC4 could significantly suppress the RANKL-induced NF-κB transcriptional activity. Based on the protein-protein interaction network, CXCL10 was identified as the differentially expressed gene with the highest connectivity degree (degree = 23); it was drastically downregulated in the presence of FNDC4, but supplementation of CXCL10 (10 ng/mL) partially ameliorated the FNDC4-induced inhibition of osteoclast formation. Taken together, we speculated that FNDC4 could suppress osteoclast formation via NF-κB pathway and downregulation of CXCL10.

Berberine alleviates oxidative stress in rats with osteoporosis through receptor activator of NF-kB/receptor activator of NF-kB ligand/osteoprotegerin (RANK/RANKL/OPG) pathway

Previous studies suggested that oxidative stress is related to the onset and development of osteoporosis. Moreover, it was demonstrated that berberine has a protective effect against oxidative stress-induced injuries. In this study, we aimed to investigate the effect and mechanism of action of berberine on rats with induced osteoporosis. Sixty 8-week-old female Wistar rats were randomly divided into the following 6 groups: control saline-treated, osteoporosis saline-treated, 3 osteoporosis berberine-treated groups (Ber 5, 10, and 20 mg/kg/body weight, respectively), and osteoporosis alendronate-treated (ALD) group. Osteoporosis was induced by bilateral ovariectomy. All treatments were performed for 8 weeks. The bone mineral density (BMD), serum alkaline phosphatase (ALP), osteocalcin, calcium, phosphorus, superoxide dismutase (SOD), methylenedioxyamphetamine (MDA), and glutathione peroxidase (GSH-Px) level was determined in the rat femur tissue. The gene and protein expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) was analyzed by quantitative reverse transcription PCR and Western blot, respectively. The BMD, SOD and GSH⁃Px levels, and the expression of OPG were significantly lower in osteoporosis compared to control group (all p < 0.05). The serum levels of osteocalcin, ALP, and MDA, and the expression of RANKL were significantly higher in osteoporosis compared to control group (all p < 0.05). Berberine, especially the high doses of berberine, effectively increased SOD, GSH⁃Px, and OPG levels as well as decreased serum osteocalcin, ALP, MDA and RANKL levels in berberine-treated osteoporosis groups (all p < 0.05). To conclude, oxidative stress may promote the development of osteoporosis in rats through the RANK/RANKL/OPG pathway. The antioxidative effect of berberine reduces the development of osteoporosis in rats to some extent.

Platycodin D Inhibits Osteoclastogenesis by Repressing the NFATc1 and MAPK Signaling Pathway

Platycodon grandiflorum root-derived saponins (Changkil saponins, CKS) are reported to have many pharmacological activities. In our latest research, CKS was proven to have a significant osteogenic effect. However, the detail molecular mechanism of CKS on osteoclastic differentiation has not been fully investigated. Administration of CKS considerably reduced OVX-induced bone loss, and ameliorated the reduction in plasma levels of alkaline phosphatase, calcium, and phosphorus observed in OVX mice. CKS also repressed the deterioration of bone trabecular microarchitecture. Interestingly, platycodin D, the most abundant and major pharmacological constituent of triterpenoid CKS, inhibited receptor activator of NF-κB ligand (RANKL)-induced activation of NF-κB, and ERK and p38 MAPK, ultimately repressing osteoclast differentiation. OVX-induced bone turnover was attenuated by CKS, possibly via repression of osteoclast differentiation by platycodin D, the active component of CKS. Platycodin D can be regarded as an antiosteoporotic candidate for treatment of osteoporosis diseases. J. Cell. Biochem. 118: 860-868, 2017. © 2016 Wiley Periodicals, Inc.