Epiberberine inhibits bone metastatic breast cancer-induced osteolysis.

ETHNOPHARMACOLOGICAL RELEVANCE: The anti-tumor related diseases of Coptidis Rhizoma (Huanglian) were correlated with its traditional use of removing damp-heat, clearing internal fire, and counteracting toxicity. In the recent years, Coptidis Rhizoma and its components have drawn extensive attention toward their anti-tumor related diseases. Besides, Coptidis Rhizoma is traditionally used as an anti-inflammatory herb. Epiberberine (EPI) is a significant alkaloid isolated from Coptidis Rhizoma, and exhibits multiple pharmacological activities including anti-inflammatory. However, the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis has not been demonstrated clearly. AIM OF THE STUDY: Bone metastatic breast cancer can lead to osteolysis via inflammatory factors-induced osteoclast differentiation and function. In this study, we try to analyze the effect of epiberberine on breast cancer and the inflammatory factors of metastatic breast cancer-induced osteolysis. METHODS: To evaluate whether epiberberine could suppress bone metastatic breast cancer-induced osteolytic damage, healthy female Balb/c mice were intratibially injected with murine triple-negative breast cancer 4T1 cells. Then, we examined the inhibitory effect and underlying mechanism of epiberberine on breast cancer-induced osteoclastogenesis in vitro. Xenograft assay was used to study the effect of epiberberine on breast cancer cells in vivo. Moreover, we also studied the inhibitory effects and underlying mechanisms of epiberberine on RANKL-induced osteoclast differentiation and function in vitro. RESULTS: The results show that epiberberine displayed potential therapeutic effects on breast cancer-induced osteolytic damage. Besides, our results show that epiberberine inhibited breast cancer cells-induced osteoclast differentiation and function by inhibiting secreted inflammatory cytokines such as IL-8. Importantly, we found that epiberberine directly inhibited RANKL-induced differentiation and function of osteoclast without cytotoxicity. Mechanistically, epiberberine inhibited RANKL-induced osteoclastogensis via Akt/c-Fos signaling pathway. Furthermore, epiberberine combined with docetaxel effectively protected against bone loss induced by metastatic breast cancer cells. CONCLUSIONS: Our findings suggested that epiberberine may be a promising natural compound for treating bone metastatic breast cancer-induced osteolytic damage by inhibiting IL-8 and is worthy of further exploration in preclinical and clinical trials.

Anticancer effect of involucrasin A on colorectal cancer cells by modulating the Akt/MDM2/p53 pathway.

Colorectal cancer (CRC) is the second leading cause of cancer mortality worldwide; however, there is still a lack of effective clinical anti-CRC agents. Naturally-occurring compounds have been considered a potentially valuable source of new antitumorigenic agents. Involucrasin A, a novel natural molecule, was isolated from Shuteria involucrata (Wall.) Wight & Arn by our team. In the present study, the anticancer activity of involucrasin A in HCT-116 CRC cells was evaluated. Firstly, the anti-proliferative effect of involucrasin A on HCT-116 cells was analyzed by sulforhodamine B and colony formation assays. The results revealed that involucrasin A exhibited a potent inhibitory effect on HCT-116 CRC cell proliferation in vitro. Subsequently, flow cytometry and western blotting indicated that involucrasin A induced apoptosis and upregulated the expression levels of apoptosis-related proteins, such as cleaved-caspase 6 and cleaved-caspase 9, in a dose-dependent manner. Mechanistically, involucrasin A significantly inhibited the phosphorylation of Akt and murine double minute 2 homologue (MDM2), which resulted in increased intracellular levels of p53. This was reversed by exogenous expression of the constitutively active form of Akt. Similarly, either knocking out p53 or knocking down Bax abrogated involucrasin A-induced proliferation inhibition and apoptosis. Together, the present study indicated that involucrasin A exerts antitumorigenic activities via modulating the Akt/MDM2/p53 pathway in HCT-116 CRC cells, and it is worthy of further exploration in preclinical and clinical trials.

Berberine targets the electron transport chain complex I and reveals the landscape of OXPHOS dependency in acute myeloid leukemia with IDH1 mutation.

Metabolic reprogramming, a newly recognized trait of tumor biology, is an intensively studied prospect for oncology medicines. For numerous tumors and cancer cell subpopulations, oxidative phosphorylation (OXPHOS) is essential for their biosynthetic and bioenergetic functions. Cancer cells with mutations in isocitrate dehydrogenase 1 (IDH1) exhibit differentiation arrest, epigenetic and transcriptional reprogramming, and sensitivity to mitochondrial OXPHOS inhibitors. In this study, we report that berberine, which is widely used in China to treat intestinal infections, acted solely at the mitochondrial electron transport chain (ETC) complex I, and that its association with IDH1 mutant inhibitor (IDH1mi) AG-120 decreased mitochondrial activity and enhanced antileukemic effect in vitro andin vivo. Our study gives a scientific rationale for the therapy of IDH1 mutant acute myeloid leukemia (AML) patients using combinatory mitochondrial targeted medicines, particularly those who are resistant to or relapsing from IDH1mi.

Exploring the pharmacological mechanisms of Shuanghuanglian against T-cell acute lymphoblastic leukaemia through network pharmacology combined with molecular docking and experimental validation.

CONTEXT: Due to the poor prognosis of T-cell acute lymphoblastic leukaemia (T-ALL), there is an urgent need to identify safer and more cost-effective drugs. OBJECTIVE: This study evaluated the antitumour activity of Shuanghuanglian (SHL) on T-ALL cells and elucidated the mechanism. MATERIALS AND METHODS: Jurkat and Molt4 cells were treated with SHL (0.1, 0.2 and 0.4 mg/mL) for 24 and 48 h. The controls were treated with RPMI 1640 containing 10% foetal bovine serum. Cell viability was evaluated through Cell Counting Kit-8 assay. Patterns of death and signalling pathway alterations caused by SHL were identified by network pharmacology combined with GO enrichment analysis and then were verified by Hoechst 33342 staining, Annexin V-FITC/PI staining and Western blotting. Interactions of the active ingredients with targets were analysed by molecular docking. RESULTS: The IC50 values of SHL in Jurkat and Molt4 cells were 0.30 ± 0.10 and 0.48 ± 0.07 mg/mL, respectively, at 24 h and 0.27 ± 0.05 and 0.30 ± 0.03 mg/mL at 48 h. In T-ALL, 117 target genes of SHL were mainly enriched in the apoptosis and NOTCH signalling pathways. SHL induced apoptosis was confirmed by Hoechst 33342 staining and flow cytometry. The protein levels of cleaved caspase-7 and cleaved PARP were significantly increased but those of cleaved NOTCH1 and MYC were reduced. The active ingredients of SHL can interact with γ-secretase.Discussion and conclusions: SHL induces apoptosis in T-ALL cells via the NOTCH1-MYC pathway and may be a potential drug for the treatment of T-ALL.

Mitochondrial toxicity evaluation of traditional Chinese medicine injections with a dual in vitro approach.

There are technical obstacles in the safety evaluation of traditional Chinese medicine (TCM) injections due to their complex chemical nature and the lack of rapid and accurate in vitro methods. Here, we established a dual in vitro mitochondrial toxicity approach combing the conventional "glucose/galactose" assay in HepG2 cells with the cytotoxic assay in mitochondrial respiration deficient cells. Using this dual in vitro approach, for the first time, we systematically assessed the mitochondrial toxicity of TCM injections. Four of the 35 TCM injections, including Xiyanping, Dengzhanhuasu, Shuanghuanglian, and Yinzhihuang, significantly reduced cellular ATP production in galactose medium in the first assay, and presented less cytotoxic in the respiration deficient cells in the second assay, indicating that they have mitochondrial toxicity. Furthermore, we identified scutellarin, rutin, phillyrin, and baicalin could be the potential mitochondrial toxic ingredients in the 4 TCM injections by combining molecular docking analysis with experimental validation. Collectively, the dual in vitro approach is worth applying to the safety evaluation of more TCM products, and mitochondrial toxic TCM injections and ingredients found in this study deserve more attention.

Betulinic Acid Protects From Bone Loss in Ovariectomized Mice and Suppresses RANKL-Associated Osteoclastogenesis by Inhibiting the MAPK and NFATc1 Pathways.

Osteoclasts with elevated bone resorption are commonly present in postmenopausal osteoporosis, and other osteolytic pathologies. Therefore, suppressing osteoclast generation and function has been the main focus of osteoporosis treatment. Betulinic acid (BA) represents a triterpenoid mainly purified from the bark of Betulaceae. BA shows multiple biological activities, including antitumor and anti-HIV properties, but its effect on osteolytic conditions is unknown. Here, BA suppressed receptor activator of nuclear factor-κB ligand (RANKL)-associated osteoclastogenesis and bone resorptive function, as assessed by tartrate-resistant acid phosphatase (TRAP) staining, fibrous actin ring generation, and hydroxyapatite resorption assays. Mechanistically, BA downregulated the expression of osteoclastic-specific genes. Western blot analysis revealed that BA significantly interrupted ERK, JNK and p38 MAPK activation as well as intracellular reactive oxygen species (ROS) production, thus altering c-Fos and NFATc1 activation. Corroborating the above findings in cell-based assays, BA prevented ovariectomy-associated bone loss in an animal model. In conclusion, these findings suggest that BA can inhibit osteoclast generation and function as well as the RANKL signaling pathway, and might be used for treating osteoclast-related osteoporosis.

Chronic chemotherapy with paclitaxel nanoparticles induced apoptosis in lung cancer in vitro and in vivo.

AIM: Paclitaxel (PTX) is an effective antitumor drug. Previous research demonstrated that paclitaxel nanoparticles (PTX-NPs) exhibited the greatest antitumor effect at 15 hours after light onset (15 HALO), but the mechanism in chronic chemotherapy is still unknown. In our study, we investigated whether PTX-NPs regulated Period2 (Per2) during chronic chemotherapy to induce apoptosis in vivo and in vitro. METHODS: To improve the antitumor effect and reduce organ damage induced by PTX treatment, PTX-NPs were prepared using a film dispersion method. Then, A549 cells were treated with PTX-NPs at 0, 5, 10, 15, and 20 HALO. An annexin/PI V-FITC apoptosis kit was measured for apoptosis, and PI was analyzed for cell cycle. The relative mechanism was detected by RT-PCR and Western blotting. Tumor volume and weight were measured to evaluate the antitumor effect of the PTX-NPs, and H&E staining was performed to assess organ damage. RESULTS: Cell cycle analysis demonstrated that PTX-NPs blocked cell cycle in G2 phase and that the ratio of cell death was significantly increased in A549 cells, while the ratios of cells in G2 phase and of apoptotic cells were highest at 15 HALO. Evaluation of in vivo antitumor activity revealed that PTX-NPs inhibited tumor growth and decreased tumor weight at 15 HALO. RT-PCR and Western blotting demonstrated that PTX-NPs upregulated Per2 mRNA and protein expression, and the highest Per2 expression was observed at 15 HALO in vivo and in vitro. Meanwhile, Bax mRNA and protein expression was upregulated, while Bcl-2 mRNA and protein expression was downregulated after PTX-NPs treatment in vivo. Moreover, H&E staining revealed that PTX-NPs reduced liver damage at 15 HALO. CONCLUSION: PTX-NPs exhibited the most effective antitumor activity and reduced liver damage at 15 HALO through upregulation of Per2 expression to induce apoptosis in vivo and in vitro.

Salidroside promotes rat spinal cord injury recovery by inhibiting inflammatory cytokine expression and NF-κB and MAPK signaling pathways.

Spinal cord injury (SCI) is a public health problem in the world. The SCI usually triggers an excessive inflammatory response that brings about a secondary tissue wreck leading to further cellular and organ dysfunction. Hence, there is great potential of reducing inflammation for therapeutic strategies of SCI. In this study, we aim to investigate if Salidroside (SAD) exerts an anti-inflammatory effect and promotes recovery of motor function on SCI through suppressing nuclear factor-κB (NF-κB) and the mitogen-activated protein kinase (MAPK) pathways. In vitro, real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) were used to examine the inhibitory effect of SAD on the expression and release of interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) activated by lipopolysaccharide (LPS) in astrocytes. In addition, SAD was found to inhibit NF-κB, p38 and extracellular-regulated protein kinases (ERK) signaling pathways by western blot analysis. Further, in vivo study showed that SAD was able to improve hind limb motor function and reduce tissue damage accompanied by the suppressed expression of inflammatory cytokines IL-1ß, IL-6, and TNF-α. Overall, SAD could reduce the inflammatory response and promote motor function recovery in rats after SCI by inhibiting NF-κB, p38, and ERK signaling pathways.

Retraction of: A005, a novel inhibitor of phosphatidylinositol 3-kinase/mammalian target of rapamycin, prevents osteosarcoma-induced osteolysis.

Osteosarcoma is the most frequent primary bone tumor in children and adolescents. The phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway is an attractive anticancer target because it plays key roles in the regulation of cell growth, division and differentiation. In this study, we demonstrated high expression of PI3K/mTOR signaling pathway-related genes in patients with osteosarcoma. We thus investigated the effects of A005, a newly synthesized dual PI3K/mTOR inhibitor, on osteosarcoma cells and in a mouse xenograft tumor model. The results confirmed that A005 inhibited the proliferation, migration and invasion of human osteosarcoma cells. In addition, A005 also inhibited receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclast differentiation and bone resorption in vitro. Therefore, A005 was further applied to a SaOS-2 osteosarcoma-induced mouse osteolysis model. A005 inhibited tumor growth and prevented osteosarcoma-associated osteolysis via modulation of the PI3K/AKT/mTOR pathway. Overall, our results showed that A005 inhibited osteoclastogenesis and prevented osteosarcoma-induced bone osteolysis by suppressing PI3K/AKT/mTOR signaling. These findings indicated that A005 may be a promising candidate drug for the treatment of human osteosarcoma.

Daidzin inhibits RANKL-induced osteoclastogenesis in vitro and prevents LPS-induced bone loss in vivo.

Osteoclasts are multinuclear giant cells responsible for bone resorption in bone loss diseases, including rheumatoid arthritis, periodontitis, and the aseptic loosening of orthopedic implants. Because of injurious side effects with currently available drugs, it is necessary to continue research novel bone-protective therapies. Daidzin, a naturally occurring isoflavone found in leguminous plants, has numerous beneficial pharmacologic effects, including anti-cancer, anti-cholesterol, and anti-angiocardiopathy, promoting osteoblasts differentiation, and even anti-osteoporosis. However, the effect of daidzin on the regulation of osteoclast activity has not yet been investigated. In this study, our study showed that daidzin significantly inhibited receptor activator of nuclear factor-kB ligand (RANKL)-induced osteoclast differentiation of bone marrow macrophages and the hydroxyapatite-resorbing activity of mature osteoclasts by inhibiting RANKL-induced NF-kB signaling pathway. In addition, daidzin could inhibit the expression of osteoclast marker genes, including nuclear factor of activated T cells cytoplasmic 1 (NFATc1), cellular oncogene fos (c-Fos), tartrate-resistant acid phosphatase (TRAP), and cathepsin K (CTSK). Consistent with in vitro results, daidzin inhibited lipopolysaccharide-induced bone loss by suppressing the osteoclast differentiation. Together our data demonstrated that daidzin inhibits RANKL-induced osteoclastogenesis through suppressing NF-ĸB signaling pathway and that daidzin is a promising agent in the treatment of osteolytic diseases.

Arctigenin inhibits RANKL-induced osteoclastogenesis and hydroxyapatite resorption in vitro and prevents titanium particle-induced bone loss in vivo.

Wear particle-induced bone resorption leads to prosthesis loosening, which is a major complication associated with total joint arthroplasty. Although the exact mechanism remains unclear, wear particle-induced extensive osteoclastogenesis plays a critical role in this process. Thus, a potential treatment of prosthetic loosening is focused on suppressing extensive osteoclast formation and bone resorption, which prevents wear particle-induced osteolysis. Arctigenin isolated from Arctium lappa has numerous beneficial pharmacologic effects, including anti-inflammatory, antiviral, and anticancer activities. Here, we explored the potential impact of arctigenin on titanium (Ti) particle-induced osteolysis in vivo. Our data showed that arctigenin significantly suppressed Ti particle-induced osteolysis and prevented bone destruction compared with Ti group. In addition, the number of osteoclasts reduced after treatment with arctigenin in vivo, indicating osteoclastogenesis might be inhibited by arctigenin. Next, bone marrow-derived macrophages were used to examine osteoclast differentiation, bone resorption, and activation of osteoclast-related signaling pathways. The results showed that arctigenin inhibited RANKL-induced osteoclastogenesis without any cytotoxicity and suppressed osteoclastic marker genes expression and hydroxyapatite resorption activity in a dose-dependent manner. Additionally, arctigenin suppressed receptor activator of nuclear factor κΒ (NF-κB) ligand-induced NF-κB activation, concomitant with retarded IκBɑ degradation and inhibition of p65 nuclear translocation, leading to impaired osteoclastogenesis. Collectively, our results suggest that arctigenin is a promising candidate for the treatment of osteoclast-related osteolytic diseases caused by excessive osteoclast formation.

Cepharanthine suppresses osteoclast formation by modulating the nuclear factor-κB and nuclear factor of activated T-cell signaling pathways.

The increased activation of osteoclasts is the major manifestation of several lytic bone diseases, including osteoporosis, rheumatoid arthritis, aseptic loosening of orthopedic implants, Paget disease and malignant bone diseases. One important bone-protective therapy in these diseases focuses on the inhibition of osteoclast differentiation and resorptive function. Given that the deleterious side-effects of currently available drugs, it is beneficial to search for effective and safe medications from natural compounds. Cepharanthine (CEP) is a compound extracted from Stephania japonica and has been found to have antioxidant and anti-inflammatory effects. In this study, we found that CEP inhibited receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclast formation and bone-resorbing activities using osteoclastogenesis and bone resorption assay. By polymerase chain reaction, we also found that CEP inhibited the expression of osteoclast-differentiation marker genes including Ctsk, Calcr, Atp6v0d2, Mmp9 and Nfatc1. Mechanistic analyses including Western blot and luciferase reporter assay revealed that CEP inhibited RANKL-induced activation of NF-κB and nuclear factor of activated T-cell, which are essential for the formation of osteoclast. Collectively, these data suggested that CEP can potentially be used as an alternative therapy for preventing or treating osteolytic diseases.

Monocrotaline Suppresses RANKL-Induced Osteoclastogenesis In Vitro and Prevents LPS-Induced Bone Loss In Vivo.

BACKGROUND/AIMS: Extensive osteoclast formation plays a critical role in bone diseases, including rheumatoid arthritis, periodontitis and the aseptic loosening of orthopedic implants. Thus, identification of agents that can suppress osteoclast formation and bone resorption is important for the treatment of these diseases. Monocrotaline (Mon), the major bioactive component of crotalaria sessiliflora has been investigated for its anti-cancer activities. However, the effect of Mon on osteoclast formation and osteolysis is not known. METHODS: The bone marrow macrophages (BMMs) were cultured with M-CSF and RANKL followed by Mon treatment. Then the effects of Mon on osteoclast differentiation were evaluated by counting TRAP (+) multinucleated cells. Moreover, effects of Mon on hydroxyapatite resorption activity of mature osteoclast were studied through resorption areas measurement. The involved potential signaling pathways were analyzed by performed Western blotting and quantitative real-time PCR examination. Further, we established a mouse calvarial osteolysis model to measure the osteolysis suppressing effect of Mon in vivo. RESULTS: In this study, we show that Mon can inhibit RANKL-induced osteoclast formation and function in a dose-dependent manner. Mon inhibits the expression of osteoclast marker genes such as tartrate-resistant acid phosphatase (TRAP) and cathepsin K. Furthermore, Mon inhibits RANKL-induced the activation of p38 and JNK. Consistent with in vitro results, Mon exhibits protective effects in an in vivo mouse model of LPS-induced calvarial osteolysis. CONCLUSION: Taken together our data demonstrate that Mon may be a potential prophylactic anti-osteoclastic agent for the treatment of osteolytic diseases caused by excessive osteoclast formation and function.

Luteoloside prevents lipopolysaccharide-induced osteolysis and suppresses RANKL-induced osteoclastogenesis through attenuating RANKL signaling cascades.

Bone destruction or osteolysis marked by excessive osteoclastic bone resorption is a very common medical condition. Identification of agents that can effectively suppress excessive osteoclast formation and function is crucial for prevention and treatment of osteolytic conditions such as periprosthetic joint infection and periprosthetic loosening. Luteoloside, a flavonoid, is a natural bioactive compound with anti-inflammation and anti-tumor properties. However, the effect of Luteoloside on inflammation-induced osteolysis is unknown. Here, we found that Luteoloside exhibited a strong inhibitory effect on lipopolysaccharide (LPS)-induced osteolysis in vivo. In addition, Luteoloside suppressed RANKL-induced osteoclast differentiation and abrogated bone resorption in a dose-dependent manner. Further, we found that the anti-osteoclastic and anti-resorptive actions of Luteoloside are mediated via blocking NFATc1 activity and the attenuation of RANKL-mediated Ca2+ signaling as well as NF-κB and MAPK pathways. Taken together, this study shows that Luteoloside may be a potential therapeutic agent for osteolytic bone diseases associated with abnormal osteoclast formation and function in inflammatory conditions.

Artesunate inhibits RANKL-induced osteoclastogenesis and bone resorption in vitro and prevents LPS-induced bone loss in vivo.

Osteoclasts are multinuclear giant cells responsible for bone resorption in lytic bone diseases such as osteoporosis, arthritis, periodontitis, and bone tumors. Due to the severe side-effects caused by the currently available drugs, a continuous search for novel bone-protective therapies is essential. Artesunate (Art), the water-soluble derivative of artemisinin has been investigated owing to its anti-malarial properties. However, its effects in osteoclastogenesis have not yet been reported. In this study, Art was shown to inhibit the nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis, the mRNA expression of osteoclastic-specific genes, and resorption pit formation in a dose-dependent manner in primary bone marrow-derived macrophages cells (BMMs). Furthermore, Art markedly blocked the RANKL-induced osteoclastogenesis by attenuating the degradation of IκB and phosphorylation of NF-κB p65. Consistent with the in vitro results, Art inhibited lipopolysaccharide (LPS)-induced bone resorption by suppressing the osteoclastogenesis. Together our data demonstrated that Art inhibits RANKL-induced osteoclastogenesis by suppressing the NF-κB signaling pathway and that it is a promising agent for the treatment of osteolytic diseases.