Yan-Qiu Liu

Wedelolactone enhances osteoblastogenesis by regulating Wnt/β-catenin signaling pathway but suppresses osteoclastogenesis by NF-κB/c-fos/NFATc1 pathway

Bone homeostasis is maintained by formation and destruction of bone, which are two processes tightly coupled and controlled. Targeting both stimulation on bone formation and suppression on bone resorption becomes a promising strategy for treating osteoporosis. In this study, we examined the effect of wedelolactone, a natural product from Ecliptae herba, on osteoblastogenesis as well as osteoclastogenesis. In mouse bone marrow mesenchymal stem cells (BMSC), wedelolactone stimulated osteoblast differentiation and bone mineralization. At the molecular level, wedelolactone directly inhibited GSK3β activity and enhanced the phosphorylation of GSK3β, thereafter stimulated the nuclear translocation of β-catenin and runx2. The expression of osteoblastogenesis-related marker gene including osteorix, osteocalcin and runx2 increased. At the same concentration range, wedelolactone inhibited RANKL-induced preosteoclastic RAW264.7 actin-ring formation and bone resorption pits. Further, wedelolactone blocked NF-kB/p65 phosphorylation and abrogated the NFATc1 nuclear translocation. As a result, osteoclastogenesis-related marker gene expression decreased, including c-src, c-fos, and cathepsin K. In ovariectomized mice, administration of wedelolactone prevented ovariectomy-induced bone loss by enhancing osteoblast activity and inhibiting osteoclast activity. Together, these data demonstrated that wedelolactone facilitated osteoblastogenesis through Wnt/GSK3β/β-catenin signaling pathway and suppressed RANKL-induced osteoclastogenesis through NF-κB/c-fos/NFATc1 pathway. These results suggested that wedelolacone could be a novel dual functional therapeutic agent for osteoporosis.

Synergistic inhibitory effect of Icariside II with Icaritin from Herba Epimedii on pre-osteoclastic RAW264.7 cell growth

Increasing evidence shows the therapeutic superiority of herbal extracts in comparison to isolated single constituents. One of the reasons may be attributed to the synergy effect of compound combinations. Flavonoids from Herba Epimedii have been shown to have therapeutic effect against bone loss. Our previous study showed that Icariside II inhibited pre-osteoclast RAW264.7 growth. The aim of this study was to investigate whether the activity of Icariside II is synergized by other components of Herba Epimedii. The inhibitory activity of Icariside II was significantly enhanced in the presence of the extract of Herba Epimedii (EHE) at the ratio of 1:1, 1:5 and 1:10. Icaritin, another flavonoid constituent, was shown here to inhibit RAW264.7 growth in a dose-dependent manner. Further, we found that Icariside II, together with Icaritin, synergistically inhibited RAW264.7 growth. The synergistic effect is significant when the ratio of Icariside II and Icaritin was 10:1, 5:1, 1:1, 1:2, and 1:5, respectively. In conclusion, Icaritin were an active component. The inhibitory activity of Icariside II on pre-osteoclast RAW264.7 growth was synergized by Icaritin, which maybe contribute to the efficiency of Herba Epimedii extract on curing bone-related diseases, such as osteoporosis.

Metabolomic profiling of emodin-induced cytotoxicity in human liver cells and mechanistic study

Emodin is one of the most representative natural anthraquinone polyphenols and the liver is one of the major target organs for drug-induced toxicology. The hepatocyte is frequently affected due to its role in emodin metabolism and accumulation. Although the hepatotoxicity of emodin has been reported, its toxicological mechanism is still unclear. The purpose of the present study was to evaluate the cytotoxicity of emodin in cultured human normal liver cells (L-02), to investigate the toxicity-related metabolic pathways and to predict the possible toxicity mechanism. Cell viability was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cytotoxicity tests demonstrated a concentration-dependent toxic effect of emodin on L-02 cells. Cells were treated for 48 h with low, medium and high doses of emodin, respectively, and then subjected to metabolomics analysis using ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS). Intracellular metabolomics analysis revealed that emodin significantly disturbed cellular glutathione and fatty acid metabolism. In addition, an emodin–cysteine adduct was identified in cell culture medium, and its level increased with increasing concentrations of emodin. The possible relationship among metabolic disorders, adduct formation and emodin hepatotoxicity was also discussed. This study provides new insight into the cytotoxicity of emodin on metabolic pathways in human liver cells.

Metabolomic Responses of Human Hepatocytes to Emodin, Aristolochic Acid, and Triptolide: Chemicals Purified from Traditional Chinese Medicines.

The present study was undertaken to investigate the metabolic responses of human liver cells HL‐7702 on chemicals purified from traditional Chinese medicine: emodin, triptolide, and aristolochic acid. Cytotoxicity tests demonstrated a dose‐dependent toxic effect of emodin, triptolide, and aristolochic acid on HL7702 cells for 48 h. Emodin (14 μM), aristolochic acid (12 μg/mL), or triptolide (18 nM) was individually administrated to HL7702 and cell samples were collected after 48 h for metabolites extraction and analysis. Pattern recognition analysis reflected the significant difference in metabolic profiles between chemical‐treated groups and the control group. Finally, eight metabolites including N1‐acetylspermidine, Glu Gly, N‐undecanoylglycine, C16 sphinganine, sphinganine, glutathione, l‐palmitoylcarnitine, and elaidic carnitine were detected as potential common biomarkers. Three pathways including sphinganine metabolism, fatty acid oxidation, and oxidative stress were identified. Our findings indicated that metabolomics would be an efficient approach to understand the molecular mechanism of hepatotoxicity induced by chemicals.

Wedelolactone inhibits osteoclastogenesis but enhances osteoblastogenesis through altering different semaphorins production

ABSTRACT Our previous study showed that wedelolactone, isolated from Ecliptae herba, enhanced osteoblastogenesis but inhibited osteoclastogenesis through Sema3A signaling pathway. This study aims to investigate the role of other semaphorins in wedelolactone‐enhanced osteoblastogenesis and ‐inhibited osteoclastogenesis. Wedelolactone inhibited RANKL‐induced Sema4D and Sema7A production, but had no effect on RANKL‐reduced Sema6D expression in osteoclastic RAW264.7 cells. In mouse bone marrow mesenchymal stem cells (BMSC), wedelolactone reversed osteogenic medium(OS)‐reduced Sema7A expression and OS‐enhanced Sema3E mRNA expression, but no effect on OS‐reduced Sema3B mRNA expression. Addition of Sema4D antibody promoted wedelolactone‐reduced TRAP activity and bone resorption pit formation. Wedelolactone combined with Sema4D antibody inhibited the formation of Sema4D‐Plexin B1 complex. In co‐culture of BMSC with RAW264.7 cells, Sema7A antibody, similar with Sema 3A antibody, reversed wedelolactone‐enhanced ALP activity and mineralization level, but promoted wedelolactone‐inhibited TRAP activity. However, Sema3E and Sema3B antibodies had no effect. Further, wedelolactone enhanced the binding of Sema7A with PlexinC1 and Beta1, but addition of Sema7A antibody partially blocked this binding. Our data demonstrated that wedelolactone inhibited Sema4D production and Sema4D‐PlexinB1 complex formation in RAW264.7 cells, thereafter inhibiting osteoclastogenesis. At the same time, wedelolactone enhanced osteoblastogenesis through promoting Sema7A production and Sema7A‐PlexinC1‐Beta1 complex formation in BMSC. HIGHLIGHTSSeveral types of semaphorins are involved in wedelolactone‐enhanced osteoblastogenesis and ‐inhibited osteoclastogenesis.Inhibition of formation of Sema4D‐PlexinB1 complex in osteoclatice RAW264.7 cells by wedelolatone.Enhancement of Sema7A‐PlexinC1‐Beta1 complex formation in bone marrow mesenchymal stem cells by wedelolactone.

Acute nephrotoxicity of aristolochic acid in vitro: metabolomics study for intracellular metabolic time-course changes

Abstract Time-course metabolic changes of aristolochic acid nephrotoxicity (AAN) was investigated using acute AAN HK-2 model. And the AAN-related biomarkers were selected. In the results, 11 potential identified biomarkers were selected and validated using multivariate method combined with time-course analysis. Several metabolic pathways, including vitamin metabolism, lipids acalytion, trytophan metabolism and protein degradation were found to be associated with AAN pathology. This research will provide a valuable reference for the discovery of more potential biomarkers of AAN progression in clinic.

A microfluidic chip-based co-culture of fibroblast-like synoviocytes with osteoblasts and osteoclasts to test bone erosion and drug evaluation

Targeting fibroblast-like synoviocyte (FLS) migration and invasion-mediated bone erosion is a promising clinical strategy for the treatment of rheumatoid arthritis (RA). Drug sensitivity testing is fundamental to this scheme. We designed a microfluidic chip-based, cell co-cultured platform to mimic RA FLS-mediated bone erosion and perform drug-sensitive assay. Human synovium SW982 cells were cultured in the central channel and migrated to flow through matrigel-coated side channels towards cell culture chamber where RANKL-stimulated osteoclastic RAW264.7 and osteogenic medium (OS)-stimulated bone marrow mesenchymal stem cells (BMSC) were cultured in the microfluidic chip device, mimicking FLS migration and invasion-mediated bone erosion in RA. These SW982 cells showed different migration potentials to osteoclasts and BMSC. The migration of SW982 cells with high expression of cadherin-11 was more potent when SW982 cells were connected with the co-culture of RAW264.7 and BMSC. Simultaneously, in the co-cultured chamber, tartrate-resistant acid phosphatase (TRAP) activity of RANKL-stimulated RAW264.7 cells was enhanced, but alkaline phosphatase (ALP) activity was decreased in comparison with mono-cultured chamber. Furthermore, it was confirmed that celastrol, a positive drug for the treatment of RA, inhibited SW982 cell migration as well as TRAP activity in the cell-cultured microfluidic chips. Thus, the migration and invasion to bone-related cells was reconstituted on the microfluidic model. It may provide an effective anti-RA drug screen model for targeting FLS migration-mediated bone erosion.

Wedelolactone Enhances Osteoblastogenesis through ERK- and JNK-mediated BMP2 Expression and Smad/1/5/8 Phosphorylation

Our previous study showed that wedelolactone, a compound isolated from Ecliptae herba, has the potential to enhance osteoblastogenesis. However, the molecular mechanisms by which wedelolactone promoted osteoblastogenesis from bone marrow mesenchymal stem cells (BMSCs) remain largely unknown. In this study, treatment with wedelolactone (2 μg/mL) for 3, 6, and 9 days resulted in an increase in phosphorylation of extracellular signal-regulated kinases (ERKs), c-Jun N-terminal protein kinase (JNK), and p38. Phosphorylation of mitogen-activated protein kinases (MAPKs), ERK and JNK started to increase on day 3 of treatment, and p38 phosphorylation was increased by day 6 of treatment. Expression of bone morphogenetic protein (BMP2) mRNA and phosphorylation of Smad1/5/8 was enhanced after treatment of cells with wedelolactone for 6 and 9 days. The addition of the JNK inhibitor SP600125, ERK inhibitor PD98059, and p38 inhibitor SB203580 suppressed wedelolactone-induced alkaline-phosphatase activity, bone mineralization, and osteoblastogenesis-related marker genes including Runx2, Bglap, and Sp7. Increased expression of BMP2 mRNA and Smad1/5/8 phosphorylation was blocked by SP600125 and PD98059, but not by SB203580. These results suggested that wedelolactone enhanced osteoblastogenesis through induction of JNK- and ERK-mediated BMP2 expression and Smad1/5/8 phosphorylation.

The inhibitory effect of Aconiti Sinomontani Radix extracts on the proliferation and migration of human synovial fibroblast cell line SW982

ETHNOPHARMACOLOGICAL RELEVANCE Aconiti Sinomontani Radix is frequently used in the treatment of Bi syndrome in traditional Chinese medicine. Several reports indicate that Aconiti Sinomontani Radix has therapeutic effects for rheumatoid arthritis (RA). However, the cellular mode of action is still unclear. To investigate the effect of alkaloid extracts of Aconiti Sinomontani Radix on proliferation and migration of human synovial sarcoma SW982 cells as well as the molecular mechanism underlying. MATERIALS AND METHODS SW982 cells were examined for proliferation by a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) method. Wound scratch assays were performed to assess the migrated rate of SW982 cells. Quantitative real-time PCR was used to measure the mRNA expression levels of Wnt5a, Runx2, MMP3, and Bmp2. Western blotting was used to measure the phosphorylated levels of JNK and NF-κB as well as the expression of MMP3. RESULTS The alkaloid extract from Aconiti Sinomontani Radix (MQA) and MQB, which removed lappaconitine from MQA significantly inhibited the proliferation of SW982 in a dose-dependent manner. The proliferation inhibitory effect of MQB was more potent. Incubation with 10μg/ml MQB for 12, 24, and 36h inhibited the migration of SW982 cells by 83%, 58%, and 42%, respectively. Treatment with different concentrations of MQB for 24h inhibited mRNA expression of Wnt5a, Runx2, and MMP3, but Bmp2 mRNA expression was elevated by MQB. Further, MQB inhibited phosphorylation of JNK and NF-κB p65 as well as MMP3 expression by Western blotting analysis. CONCLUSION The results showed that MQB inhibited proliferation and migration of SW982 cells possibly through suppressing Wnt5a-mediated JNK and NF-κB pathways. These results indicated that MQB might be an active extract of Aconiti Sinomontani Radix for targeting fibroblast-like synoviocytes (FLS) and be potential for RA therapy.

Effect of hydroxyapatite nanoparticles and wedelolactone on osteoblastogenesis from bone marrow mesenchymal stem cells: Effect of HAp nanoparticles and wedelolactone on osteoblastogenesis

Regenerative medicine has a high demand for the development of scaffold materials combined with other osteogenic inducers to generate bioactive composite materials for bone replacement therapies. Previously, we reported that wedelolactone promoted osteoblastogenesis of bone marrow mesenchymal stem cells (BMSCs). In this study, the effect of hydroxyapatites (HAps), bone composite materials we prepared, and the combined effect of wedelolactone and HAps on osteoblastogenesis differentiation was first evaluated. Three kinds of HAps constructed by a rod-like shape with particle size of 25 nm (HAp-1), 37 nm (HAp-2), and 33 nm (HAp-3) did not affect BMSC survival, but induced activity of alkaline phosphatase(ALP), a marker enzyme for osteoblastogenesis. HAp-1 treatment resulted in a more significant increase in the number of ALP staining-positive BMSC, and maintained an extended time for the increased number of ALP staining-positive BMSC. Moreover, HAp-1 combined with wedelolactone induced a higher ALP activity for a longer time than HAp-2 and HAp-3, and also increased the bone mineralization level. Osteoblastogenesis-related marker genes expression including osteorix, osteocalcin, and runx2 were increased after BMSC were treated with HAp-1 for 6 days. Although three kinds of HAps treatment for 9 days increased osteorix mRNA expression, osteocalcin, and runx2 mRNA expression levels were upregulated only by HAp-1. Similarly, only HAp-1 enhanced wedelolactone-induced osteocalcin, osteorix, and runx2 mRNA expression after 9 days treatment. Together, these results suggested that HAps with different sizes generated different effect on osteoblastogenesis. HAp-1 combined with wedelolacone can exert an enhanced effect on osteoblastogenesis, which has potential for treating osteoporosis.