Anti-Histone H3 (T22) Antibody (A25430)

Wogonoside, a main flavonoid component derived from the root of Scutellaria baicalensis Georgi, has been reported to have anti-angiogenesis and anti-leukemia activities. However, whether it can inhibit tumor angiogenesis is unclear. In this study, we investigate the inhibitory effect of wogonoside on angiogenesis in breast cancer and its underlying mechanisms. ELISA assay shows that wogonoside (25, 50, and 100 µM) decreases the secretion of VEGF in MCF-7 cells by 30.0%, 35.4%, and 40.1%, respectively. We find it inhibits angiogenesis induced by the conditioned media from MCF-7 cells in vitro and in vivo by migration, tube formation, rat aortic ring, and chicken chorioallantoic membrane (CAM) assay. Meanwhile, wogonoside can inhibit the growth and angiogenesis of MCF-7 cells xenografts in nude mice. The reduction of tumor weight can be found both in wogonoside (80 mg/kg) and bevacizumab (20 mg/kg) treated group, and the tumor inhibition rate is 42.1% and 48.7%, respectively. In addition, mechanistic studies demonstrate that wogonoside suppresses the activation of Wnt/β-catenin pathway in MCF-7 cells. Wogonoside (100 µM) decreases the intracellular level of Wnt3a, increases the expression of GSK-3β, AXIN, and promotes the phosphorylation of β-catenin for proteasome degradation significantly. Furthermore, the nuclear accumulation of β-catenin and the DNA-binding activity of β-catenin/TCF/Lef complex are inhibited by 49.2% and 28.7%, respectively, when treated with 100 µM wogonoside. Taken together, our findings demonstrate that wogonoside is a potential inhibitor of tumor angiogenesis and can be developed as a therapeutic agent for breast cancer.

© 2015 Wiley Periodicals, Inc.

In this study, we aimed to investigate the antitumor effect of LYG-202, a newly synthesized piperazine-substituted derivative of flavonoid on human breast cancer cells and illustrate the potential mechanisms. LYG-202 induced apoptosis in MCF-7, MDA-MB-231 and MDA-MB-435 cells. LYG-202 triggered the activation of mitochondrial apoptotic pathway through multiple steps: increasing Bax/Bcl-2 ratio, decreasing mitochondrial membrane potential (ΔΨ(m)), activating caspase-9 and caspase-3, inducing cleavage of poly(ADP-ribose) polymerase, cytochrome c release and apoptosis-inducing factor translocation. Furthermore, LYG-202 inhibited cell cycle progression at the G1/S transition via targeting Cyclin D, CDK4 and p21(Waf1/Cip1). Additionally, LYG-202 increased the generation of intracellular ROS. N-Acetyl cysteine, an antioxidant, reversed LYG-202-induced apoptosis suggesting that LYG-202 induces apoptosis by accelerating ROS generation. Further, we found that LYG-202 deactivated the PI3K/Akt pathway, activated Bad phosphorylation, increased Cyclin D and Bcl-xL expression, and inhibited NF-κB nuclear translocation. Activation of PI3K/Akt pathway by IGF-1 attenuated LYG-202-induced apoptosis and cell cycle arrest. Our in vivo study showed that LYG-202 exhibited a potential antitumor effect in nude mice inoculated with MCF-7 tumor through similar mechanisms identified in cultured cells. In summary, our results demonstrated that LYG-202 induced apoptosis and cell cycle arrest via targeting PI3K/Akt pathway, indicating that LYG-202 is a potential anticancer agent for breast cancer.

Microenvironmental hypoxia gives many tumor cells the capacity for drug resistance. Thioredoxin family members play critical roles in the regulation of cellular redox homeostasis in a stressed environment. In this study, we established a hypoxia-drug resistance (hypoxia-DR) model using HepG2 cells and discovered that the overexpression and nuclear translocation of thioredoxin-1 (Trx-1) are closely associated with this resistance through the regulation of the metabolism by the oxidative stress response to glycolysis. Intranuclear Trx-1 enhances the DNA-binding activity of HIF-1α via its interaction with and reducing action on Ref-1, resulting in increased expression of glycolysis-related proteins (PDHK1, HKII, and LDHA), glucose uptake, and lactate generation under hypoxia. Meanwhile, we found that GL-V9, a newly synthesized flavonoid derivative, shows an ability to reverse the hypoxia-DR and has low toxicity both in vivo and in vitro. GL-V9 could inhibit the expression and nuclear translocation of Trx-1 and then suppress HIF-1α DNA-binding activity by inhibiting the Trx-1/Ref-1 axis. As a result, glycolysis is weakened and oxidative phosphorylation is enhanced. Thus, GL-V9 leads to an increment in intracellular ROS generation and consequently intensified apoptosis induced by DDP.

β-Catenin is a key regulator of leukemia stem cell maintenance and drug resistance. Herein, we investigated the protective effects of the stromal cell-mediated VE-cadherin-β-catenin signal on Ph+ leukemia cells during imatinib treatment. We found stromal cells could desensitize imatinib and up-regulate VE-cadherin expression on Ph+ leukemia cells (K562 and SUP-B15 cells), which further stabilized and activated β-catenin. Knockdown of VE-cadherin with shRNA diminished the β-catenin protein and partly resensitized Ph+ leukemia cells to imatinib despite the presence of stromal cells, suggesting VE-cadherin is a potential target in the treatment of Ph+ leukemia.

Amyloid-β peptide (Aβ), which can invoke a cascade of inflammatory responses, is considered to play a causal role in the development and progress of Alzheimer's disease (AD). Montelukast, known as a cysteinyl leukotriene receptor 1 (CysLT1R) antagonist, is currently used for treatment of inflammatory diseases such as asthma. We have previously reported that CysLT1R activation is involved in Aβ generation. In this study, we investigated rescuing effect of CysLT1R antagonist montelukast on Aβ1-42-induced neurotoxicity in primary neurons. Our data showed that Aβ1-42 elicited a marked increase of CysLT1R expression in primary mouse neurons. This increment of CysLT1R expression was accompanied by increases of inflammatory factors such as NF-κB p65, tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β) as well as pro-apoptotic protein Caspase-3 activation and anti-apoptosis protein Bcl-2 reduction. Aβ1-42-mediated increase of CysLT1R expression was associated with Aβ1-42-induced cytotoxicity as measured by MTT reduction assay and lactate dehydrogenase (LDH) release assay. This observation was confirmed with treatment of montelukast, a selective CysLT1R antagonist, which had significant effect on Aβ1-42-induced cytotoxicity. Moreover, blockade of CysLT1R with montelukast reversed Aβ1-42-mediated increase of CysLT1R expression, and concomitant changes of the pro-inflammatory factors and the apoptosis-related proteins. The results demonstrate that montelukast rescued neurons against Aβ1-42-induced neurotoxicity, neuroinflammation and apoptosis by down-regulating CysLT1R-mediated NF-κB signaling, suggesting that CysLT1R may be a potential target for AD, and its antagonist may have beneficial effects for treatment of AD.

Wogonin has been shown to have anti-angiogenesis and anti-tumor effects. However, whether wogonin inhibits LPS-induced tumor angiogenesis is not well known. In this study, we investigated the effect of wogonin on inhibiting LPS-induced tumor angiogenesis and further probed the underlying mechanisms. ELISA results revealed that wogonin could suppress LPS-induced VEGF secretion from tumor cells. Transwell assay, tube formation assay, rat aortic ring assay and CAM model were used to evaluate the effect of wogonin on angiogenesis induced by MCF-7 cell (treated with LPS) in vitro and in vivo. The inhibitory effect of wogonin on angiogenesis in LPS-treated MCF-7 cells was then confirmed by the above in vitro and in vivo assays. The study of the molecular mechanism showed that wogonin could suppress PI3K/Akt signaling activation. Moreover, wogonin inhibited nuclear translocation of NF-κB and its binding to DNA. The result of real-time PCR and luciferase reporter assay suggested that VEGF expression was down-regulated by wogonin primarily at the transcriptional level. IGF-1 and p65 expression plasmid were used to activate PI3K/Akt and NF-κB pathways, and to observe the effect of wogonin on the simualtion of PI3K/Akt/NF-κB signaling. Taken together, the result suggested that wogonin was a potent inhibitor of tumor angiogenesis and provided a new insight into the mechanisms of wogonin against cancer.

Differentiation of preadipocytes into adipocytes and the formation of the subsequent adipose tissue are critical for mammalian growth and development. The molecular mechanism relating to preadipocyte differentiation and adipogenesis from the perspective of miRNAs is not yet completely understood. Here we investigated whether miR-183 functioned in the differentiation process. Both gain-of-function and loss-of-function assays demonstrated that miR-183 positively regulated 3T3-L1 differentiation by enhancing the expression of adipogenic marker genes such as CCAAT/enhancer binding protein α (C/EBPα), peroxisome proliferator-activated receptor γ (PPARγ), adiponectin and fatty acid synthase (FAS), as well as the triglyceride content and accumulation of lipid droplets. Meanwhile, low-density lipoprotein receptor-related protein 6 (LRP6) was known to impair the canonical Wnt/β-catenin signaling pathway and thereafter reduce c-myc and nuclear β-catenin protein. We showed that the inhibition of LRP6 by siRNA promoted 3T3-L1 adipogenic differentiation and adipogenesis. Further analysis showed that mouse miR-183 gene had its own transcription unit containing CpG islands, transcription start site (TSS), coding sequence (CDS) and polyA signal within the flanking sequences 2500 nt upstream and downstream of mouse miR-183 in genome. The core promoter of miR-183 gene was identified and transcription factor GATA3 (GATA binding protein 3) significantly inhibited the expression of mature miR-183 by binding to its core promoter in vivo, as indicated by the chromatin immunoprecipitation (ChIP) assay. These results suggest that miR-183, though negatively regulated by transcription factor GATA3, enhances 3T3-L1 preadipocyte differentiation and adipogenesis through the inhibition of the canonical Wnt/β-catenin signaling pathway by targeting LRP6.

Wogonoside, one flavonoid derived from the root of Scutellaria baicalensis Georgi, has been reported for its anti-inflammation activity; however, whether it can inhibit inflammation-induced angiogenesis is still unclear. In the present study, we evaluated the effect of wogonoside on lipopolysaccharide (LPS)-induced angiogenesis in vitro and in vivo. Wogonoside suppressed the LPS-stimulated migration and tube formation of human umbilical vein endothelial cells (HUVECs), as well as microvessel sprouting from rat aortic rings in vitro. Moreover, wogonoside also inhibited LPS-stimulated vessel growth of Chicken chorioallantoic membrane (CAM) in vivo. The mechanism revealed that wogonoside inhibited LPS-induced toll-like receptor 4 (TLR4) up-regulation and its downstream mitogen-activated protein kinases (MAPKs) activation, by decreasing the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase. The results suggest that wogonoside inhibits LPS-induced angiogenesis both in vitro and in vivo, and that it might have a therapeutic potential for the diseases associated with the development of both inflammation and angiogenesis progress.

The potential influence of intranasal testosterone propionate (InTP) supplements on mesodopaminergic system in aged male rats was investigated by analyzing the exploratory and motor behaviors as well as dopamine neurobiochemical indices. Meanwhile, oxidative stress parameters and pathway of nuclear factor erythroid 2-related factor 2 (Nrf2)-binding antioxidant response elements (Nrf2-ARE) were examined to check whether the Nrf2-ARE pathway was involved in the InTP-induced alteration of mesodopaminergic system in aged male rats. The exploratory and motor behavioral deficits, as well as the reduced expression of dopamine, tyrosine hydroxylase, and dopamine transporter, which indicated the declined activity of mesodopaminergic system, were ameliorated in rats administered with 12-week InTP. The results indicated that chronic InTP supplements could effectively influence the brain function activity in a way opposite to the effect of aging on the mesodopaminergic system of rats. The increased levels of Nrf2, heme oxygenase-1, and

NAD(P)H:

quinone oxidoreductase-1 in the substantia nigra and ventral tegmental area, but not in the hippocampus of InTP-administered aged male rats, indicated that the ameliorative effect of InTP supplements on mesodopaminergic system might be related to the region-specific activation of the Nrf2-ARE pathway.

Copyright © 2016 Elsevier Inc. All rights reserved.

INTRODUCTION:

Estrogen plays an important role in the osteogenic differentiation of mesenchymal stem cells, while stem cells from apical papilla (SCAP) can contribute to the formation of dentin/bone-like tissues. To date, the effects of estrogen on the differentiation of SCAP remain unclear.

METHODS:

SCAP was isolated and treated with 10⁻⁷ M 17beta-estradiol (E2). The odonto/osteogenic potency and the involvement of mitogen-activated protein kinase (MAPK) signaling pathway were subsequently investigated by using methyl-thiazolyl-tetrazolium (MTT) assay, and other methods.

RESULTS:

MTT and flow cytometry results demonstrated that E2 treatment had no effect on the proliferation of SCAP in vitro, while alkaline phosphatase (ALP) assay and alizarin red staining showed that E2 can significantly promote ALP activity and mineralization ability in SCAP. Real-time reverse transcription polymerase chain reaction (RT-PCR) and western blot assay revealed that the odonto/osteogenic markers (ALP, DMP1/DMP1, DSPP/DSP, RUNX2/RUNX2, OSX/OSX and OCN/OCN) were significantly upregulated in E2-treated SCAP. In addition, the expression of phosphor-p38 and phosphor-JNK in these stem cells was enhanced by E2 treatment, as was the expression of the nuclear downstream transcription factors including phosphor-Sp1, phosphor-Elk-1, phosphor-c-Jun and phosphor-c-Fos, indicating the activation of MAPK signaling pathway during the odonto/osteogenic differentiation of E2-treated SCAP. Conversely, the differentiation of E2-treated SCAP was inhibited in the presence of MAPK specific inhibitors.

CONCLUSIONS:

The ondonto/osteogenic differentiation of SCAP is enhanced by 10⁻⁷ M 17beta-estradiol via the activation of MAPK signaling pathway.

OBJECTIVE:

This study was designed to investigate the effects of mineral trioxide aggregate (MTA) on the osteo/odontogenic differentiation of inflammatory dental pulp stem cells (iDPSCs).

MATERIALS AND METHODS:

inflammatory DPSCs were isolated from the inflammatory pulps of rat incisors and cocultured with MTA-conditioned medium. MTT assay and flow cytometry were performed to evaluate the proliferation of iDPSCs. Alkaline phosphatase (ALP) activity, alizarin red staining, real-time RT-PCR, and Western blot assay were used to investigate the differentiation capacity as well as the involvement of NF-κB pathway in iDPSCs.

RESULTS:

Mineral trioxide aggregate-treated iDPSCs demonstrated the higher ALP activity and formed more mineralized nodules than the untreated group. The odonto/osteoblastic markers (Alp, Runx2/RUNX2, Osx/OSX, Ocn/OCN, and Dspp/DSP, respectively) in MTA-treated iDPSCs were significantly upregulated as compared with untreated iDPSCs. Mechanistically, cytoplastic phos-P65 and nuclear P65 in MTA-treated iDPSCs were significantly increased in a time-dependent manner. Moreover, the inhibition of NF-κB pathway suppressed the MTA-induced odonto/osteoblastic differentiation of iDPSCs, as indicated by decreased ALP levels, weakened mineralization capacity and downregulated levels of odonto/osteoblastic genes (Osx, Ocn, and Dspp).

CONCLUSIONS:

Mineral trioxide aggregate enhances the odonto/osteogenic capacity of DPSCs from inflammatory sites via activating the NF-κB pathway.

© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.