Diallyl sulfide inhibits murine WEHI-3 leukemia cells in BALB/c mice in vitro and in vivo

2009 ◽  
Vol 28 (12) ◽  
pp. 785-790 ◽  
Author(s):  
Fu-Shun Yu ◽  
Chih-Chung Wu ◽  
Chi-Tsai Chen ◽  
Shang-Pang Huang ◽  
Jai-Sing Yang ◽  
...  
Keyword(s):  
B Cells ◽  
Allium Sativum ◽  
Leukemia Cells ◽  
T And B Cells ◽  
Control Groups ◽  
Diallyl Sulfide ◽  
In Vivo Effects ◽  
Dose Dependent

It is well documented that enhanced garlic (Allium sativum) consumption leads to decrease in the cancer incidences. Diallyl sulfide (DAS), one of the components of garlic, induces cytotoxicity and apoptosis in many cancer cell lines. The present studies are focused on the in vivo effects of DAS on leukemia WEHI-3 cells in the BALB/c mice. We examined the effects of DAS on the cytotoxicity of WEHI-3 cells and results indicated that DAS decreased the percentage of viable WEHI-3 cells and these effects are dose-dependent. We examined the effects of DAS on WEHI-3 in vivo and the results indicated that DAS decreased the percentage of Mac-3 and CD11b, indicating that the differentiation of the precursor of macrophage cells was inhibited. DAS stimulated the percentage of CD3 and CD19, indicating that the differentiation of the precursor of T and B cells promoted. The weights of liver and spleen indicated that DAS decreased the weight of these organs after being compared to the control groups. One of the major characteristic of WEHI-3 leukemia is the enlarged spleen in murine after intraperitoneal (i.p.) injection of WEHI-3 cells. In conclusion, DAS affects WEHI-3 cells both in vitro and in vivo.

Synergistic Reactivation Of Cancer/Testis Antigens By Combination Treatment With Decitabine and Histone Deacetylase Inhibitors (Valproate, Panobinostat) In Myeloid Leukemia Cells

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3763-3763
Author(s):  
Nadja Blagitko-Dorfs ◽  
Tobias Bauer ◽  
Maren Prinz ◽  
Wolfram Brugger ◽  
Gesine Bug ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Myeloid Leukemia ◽  
Histone Deacetylase Inhibitors ◽  
Leukemia Cells ◽  
Cancer Testis Antigens ◽  
Dose Dependent ◽  
Hdaci Treatment ◽  
Cancer Testis

Abstract Introduction Epigenetic therapies with azanucleoside DNA hypomethylating agents, alone or in combination with histone deacetylase inhibitors (HDACi), show clinical activity in myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML), particularly when given at non-cytotoxic doses. They are able to reactivate epigenetically silenced genes including, among others, a number of highly immunogenic proteins dubbed Cancer/testis antigens (CTAs), predominantly the CTAs located on the X chromosome. We have previously shown that decitabine can induce expression of several CTAs, including MAGEB2 and NY-ESO-1, in myeloid cells in vitro and thereby trigger an immune response (Almstedt et al., Leuk. Res. 2010). Induction of a CTA-specific cytotoxic T cell response in vivo was reported also in AML patients treated with azacitidine and sodium valproate (VPA) and correlated with clinical response (Goodyear et al., Blood 2010). To the best of our knowledge, no data have yet been reported on the effect of combination treatment with decitabine and panobinostat or sodium valproate (VPA) on CTA reactivation in myeloid leukemia. Aim We hypothesized that by combining decitabine with HDACi we could further enhance expression of CTAs in myeloid leukemia cells and thereby boost recognition of the malignant cells by the cytotoxic T lymphocytes. Methods The myeloid cell lines U937 and Kasumi-1 were treated with decitabine alone or in combination with the HDACi VPA or panobinostat applied at non-toxic concentrations (>80% cell viability). Expression of CTAs was analyzed by RT-qPCR and Western blot after 48 hours of HDACi treatment. DNA methylation of NY-ESO-1 and MAGEB2 promoter regions was quantified by pyrosequencing. Bone marrow mononuclear cells from 19 AML patients (treated with or without VPA as add-on to decitabine in the ongoing randomized phase II DECIDER clinical trial, NCT00867672) were collected before and on day 15 of treatment, in some patients also after 2 treatment cycles. CTA mRNA expression and promoter DNA methylation were quantified as described above. Results VPA or panobinostat alone did not induce MAGEB2 or NY-ESO-1 expression in vitro. However the pretreatment of cells with decitabine prior to addition of either HDACi resulted in a synergistic dose-dependent reactivation of MAGEB2 and NY-ESO-1 on the mRNA level (confirmed for the latter on the protein level). Pyrosequencing analysis of the heavily methylated NY-ESO-1 and MAGEB2 promoters revealed, as expected, no methylation changes upon HDACi treatment, but a dose-dependent hypomethylation upon decitabine. In recently initiated in vivo studies (DECIDER trial), until now cells from 19 AML patients receiving epigenetic treatment were sequentially analyzed. Induction of MAGEB2 mRNA was observed in 9 patients (from absent to a median of 0.002 relative to GAPDH, range 0.0004-0.043), with concomitant DNA hypomethylation of the MAGEB2 promoter from median 83% pretreatment methylation (range 63%-90%) to 63% posttreatment (range 44%-74%). In 5 patients modest hypomethylation without changes in MAGEB2 expression was observed (from median pretreatment values of 89% [72%-92%] to 82% [58%-87%] posttreatment). Another 5 patients disclosed neither hypomethylation nor reexpression of MAGEB2 (results as yet blinded to treatment arm and clinical response). Conclusions Combined epigenetic treatment with the hypomethylating agent decitabine and the HDACi VPA or panobinostat synergistically induced a dose-dependent reactivation of the CTAs MAGEB2 and NY-ESO-1 in vitro, accompanied by promoter hypomethylation. First translational results of the DECIDER AML trial also indicate in vivo effects of the epigenetic treatment on CTA induction. The unmasking of CTAs to the immune system by epigenetically active drugs can increase anti-tumor immune responses, and thus has clear implications for future clinical trials combining epigenetic therapy and specific immunotherapy in myeloid neoplasia. Disclosures: No relevant conflicts of interest to declare.

Novel CRM-1 Inhibitors for Therapy In Mantle Cell Lymphoma

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2734-2734
Author(s):  
Kejie Zhang ◽  
Lan V Pham ◽  
Liang Zhang ◽  
Archito T. Tamayo ◽  
Zhishuo Ou ◽  
...  
Keyword(s):  
B Cells ◽  
Western Blot ◽  
Mantle Cell Lymphoma ◽  
Cell Lines ◽  
Cell Lymphoma ◽  
Parp Cleavage ◽  
Mantle Cell ◽  
Dose Dependent

Abstract Abstract 2734 Chromosomal Region Maintenance 1 (CRM1) overexpression has been associated with cancer progression and mortality in several human cancers, suggesting that activation of nuclear export may play a role in human neoplasia and may serve as a novel target for the treatment of cancers. This overexpression of CRM1 may be related to the export of most tumor suppressor and growth regulatory proteins out of the nucleus, thereby functionally inactivating them. Mantle cell lymphoma (MCL) is an aggressive histotype of B-cell non-Hodgkin lymphoma that is not yet curable. The objective of our study was to investigate the status of CRM1 in MCL, both in MCL cell lines and primary MCL cells, in comparison to normal B cells, and to evaluate the therapeutic efficiency of CRM1 inhibition in MCL in vitro and in vivo, and to elucidate the mechanism of CRM1 inhibitor-mediated MCL cell apoptosis. We used 8 established MCL cell lines and primary cells from 4 patients with relapsed/refractory MCL. KPT185 and KPT276 are novel, highly selective, drug-like small molecular CRM1 inhibitors. Western Blot analysis showed that CRM1 was expressed in both the cytoplasm and nuclei of 8 MCL cell lines. CRM1 was mainly detected in nuclei of normal resting B cells; In contrast, CRM1 was primarily detected in the cytoplasm of freshly isolated primary MCL cells from patients with relapsed/refractory MCL. In 3H-thymidine incorporation assays, inhibition of CRM1 by KPT185 resulted in a significant dose-dependent growth inhibition of 8 MCL cells, with IC50 values range between 10 nM to 120 nM. The blastoid-variant MCL cell lines (Z-138 and Rec-1) were significantly more sensitive to KPT185 than the non-blastoid variant MCL cell lines. Flow cytometry analysis with fluorescence-labeled Annexin V and propidium iodide showed that KPT185 induced MCL cells apoptosis in both time- and dose-dependent manners, but had no effect on cell cycle arrest. MCL cells treated with KPT185 for 12 hours showed caspase 3 activation and PARP cleavage. As shown in Western blot and confocal microscopy, blocking CRM1 activity by KPT185 in MCL cells up-regulated the protein expression of p53, a known CRM1-mediated export protein, and also induced CRM1 translocation to the nucleus and decreased CRM1 expression. In severe combined immunodeficient (SCID) mice bearing palpable Z-138 tumors, treatment with KPT-276 (similar structure to KPT-185 but improved animal pharmacokinetics), 50mg/kg or 150 mg/kg PO QDx5 each week, or cyclophosphamide 100 mg/kg on days 1–3, was initiated. Tumor growth was significantly inhibited (>75%) in all of treatment groups compared with vehicle control. Neutropenia and other cytotoxic-agent specific effects have not been observed in treated animals. In conclusion, CRM1 inhibitors inhibited growth of MCL cells in vitro and in vivo, and induced apoptosis of MCL cells via inhibition of CRM1 expression and blockage of its translocation with functional nuclear proteins. Our data suggest that novel CRM1 inhibitors provide a potential therapy for patients with relapsed/refractory MCL. Disclosures: No relevant conflicts of interest to declare.

Mesenchymal Stromal Cells Suppress T-and B-Cells via Galectin-9 in a Donor Dependent Manner

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1248-1248
Author(s):  
Christopher Ungerer ◽  
Patricia Quade-Lyssy ◽  
Reinhard Henschler ◽  
Erhard Seifried ◽  
Heinfried Radeke ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
Immune Suppression ◽  
Immune Cells ◽  
Stromal Cells ◽  
Coagulation Factor ◽  
T And B Cells ◽  
Ifn Γ

Abstract Abstract 1248 Therapeutic approaches using multipotent mesenchymal stromal cells (MSCs) are advancing in regenerative medicine, transplantation and autoimmune diseases. Until now the way of action for MSC-mediated immune suppression is still controversial and relies most probably on a multifactorial mechanism. MSCs have been demonstrated to produce the suppressive molecules hepatocyte growth factor (HGF), tumor growth factor-β (TGF-β), prostaglandin E2 (PGE2) and indoleamine 2,3-dioxygenase (IDO). Furthermore, it has been described that immunosuppression by MSCs is enhanced via stimulation with interferon-γ (IFN-γ). Recently, galectin-1, a β-galactoside binding lectin with immune modulatory properties, has been added to the group of immune modulatory molecules that are responsible for MSC-mediated immune suppression. Here, we identified galectin-9 (Gal-9) as a new molecule involved in MSC-mediated immune modulation. First, we isolated MSCs from bone marrow of randomly selected donors and performed several in vitro experiments regarding their immune modulatory potential (e.g proliferation and IgG production). Interestingly, Gal-9 was the only investigated protein, which was strongly upregulated in MSCs upon activation with IFN-γ. We moreover demonstrate that Gal-9 is a major mediator of the anti-proliferative effect of MSCs on T-cells. Although a B-cell suppressive function of Gal-9 has previously not been reported, we were surprised to detect the same inhibitory effect on isolated B-cells. Proliferation of immune cells was triggered upon either stimulation with either PHA and LPS, or CD40L and PHA. Activation of MSCs with IFN-γ resulted in a major decrease of proliferation of both T-cells and B-cells. In addition, Gal-9 and activated MSCs contribute to the suppression of VZV triggered immunoglobulin release as well. Again activation of MSCs with IFN-γ decreased the IgG release, whereas blocking Gal-9 with lactose, a well characterized inhibitor of Gal-9 function, reversed the effect almost completely. Further, we determined that Gal-9 expression levels (mRNA and protein) distinguish between MSC cultures from different donors after activation. Among donors, we could differentiate between individuals with high Gal-9 levels and higher immune modulatory potential and such with low Gal-9 expression and lower immune modulatory potential. Compared to untreated MSCs we demonstrated a three- to fifty-fold rise in Gal-9 levels after prior activation with IFN-γ. In addition, we demonstrated the upregulation of Gal-9 in MSCs by cell-cell contacts with either T-or B-cells. The upregulation was additionally at least two fold increased by previeously activating MSCs with IFN-γ. Because our group is interested in the therapy of hemophilia A and because of the unxpected suppressive effect of Gal-9 on B-cells and B-cell function, we next tested the effect of MSCs and Gal-9 on the induction of inhibitory antibodies to coagulation factor VIII (FVIII). Mice were immunized with human coagulation factor VIII (FVIII) in the presence or absence of either human MSCs, anti-murine Gal-9 or human Gal-9. As predicted, MSCs suppressed and anti-Gal-9 antibodies anhanced antibody formation. However in contrary to the expected, human Gal-9 co-treatment enhanced the anti-FVIII antibody response. A set of additional experiments revealed, that human Gal-9 suppresses murine regulatory T-cells in vivo. Further, in contrast to human immune cells, murine-derived T- and B-cells did not respond to human recombinant Gal-9 in vitro, but human IFN-γ activated MSCs were able to suppress proliferation of murine immune cells. Because of only 60% homology of murine and human Gal-9 we assume that the murine model cannot predict the function of human Gal-9 and that MSC-mediated immune modulatory functions are exerted via alternative pathways in this setting. Experiments with murine Gal-9 to demonstrate the in vivo function of Gal-9 are ongoing. In conclusion, Gal-9 is novel mediator of MSC immunomodulatory functions and affectsmultiple immune cell types including B-cells. Gal-9 is differentially expressed in MSCs from different donors and may therefore serve as a predictive indicator for clinical MSC functionality. Disclosures: No relevant conflicts of interest to declare.

AT-101, a Pan-Inhibitor of Bcl-2 Family Anti-Apoptotic Proteins Antagonizes the Protective Effect Conferred by Nurselike Cells on Primary Chronic Lymphocytic Leukemia (CLL) Cells.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2100-2100 ◽  
Author(s):  
Danelle F. James ◽  
Rebecca M. Mervis ◽  
Ruzbeh Mosadeghi ◽  
Thomas J. Kipps
Keyword(s):  
B Cells ◽  
Cell Viability ◽  
Single Agent ◽  
Leukemia Cells ◽  
Drug Induced ◽  
Accessory Cells ◽  
The Mean ◽  
Apoptotic Proteins

Abstract Despite the longevity of CLL B cells in vivo, in vitro CLL cells readily undergo apoptosis under conditions that support the growth of normal B cells. However, when leukemia cells are co-cultured with non-neoplastic accessory cells, such as those found in the marrow stroma and nurselike cells (NLC) that can differentiate from blood mononuclear cells they become resistant to spontaneous and drug induced cell death. These findings suggest that the defective apoptosis of the CLL B cells is not only ascribed to intrinsic defects in the neoplastic cell, but also to extrinsic factors that influence their behavior provided by the tumor microenvironment. As such, identification of molecular targets that link malignant B cells to supportive cells in the microenvironment may lead to new therapeutic avenues for CLL patients. For example, we have found that co-culture with NLC induces expression of Mcl-1, an anti-apoptotic protein of the Bcl-2 family in CLL cells. [Nishio M 2005] Induction of such prosurvival proteins by accessory cells may play a role disease aggressiveness and leukemia cell resistance to chemotherapy in vivo. AT-101 is a small molecule that mimics the inhibitory BH3 domain of endogenous antagonists of the Bcl-2 family anti-apoptotic proteins negating their cytoprotective role. Fluorescence polarization assays demonstrate that AT -101 binds to Bcl-2, BcL-XL, Bcl-W, and Mcl-1. AT-101 is cytotoxic to primary CLL cells in vitro and has been shown to have single agent activity in high risk CLL patients. Therefore, we hypothesized that inhibition of Mcl-1 by AT-101 may diminish the protection of NLC on CLL cells and may render the leukemia cells more sensitive to spontaneous and drug induced apoptosis. Primary CLL cells from 20 different patients were plated with or without NLCs, and cell viability was assessed overtime. Co-culture of CLL cells with NLC protected the CLL cells from undergoing spontaneous apoptosis. After 48 hours the average viability (+/− SEM) of CLL cells with NLC was 75% (+/− 4%) whereas the mean viability of CLL cultured alone was significantly lower at 59% (+/−5%) (p<0.02). In addition, we found that co-culture of CLL cells with NLC protected the leukemia cells from the cytotoxic effects of fludarabine (F-ara-A). For instance, after 48 hours after treatment with 10 μM F-ara-A the mean viability of the CLL cells was 28% (+/− 4%) whereas the viability of CLL cells cultured with NLC was 51% (+/−4%), a difference that was highly significant (p<0.001). In contrast, NLC could not protect leukemia cells from apoptosis induced by AT-101. For example, treatment of CLL cells with AT-101 at 5 μM, with or without NLC, resulted in CLL cell viability at 48 hours of only 40% (+/−7%.) or 30% (+/−7%.), respectively, a difference that was not statistically significant. AT-101 and F-ara-A were titrated in the setting of NLC and appeared to act additively in inducing apoptosis of CLL cells. In fact, NLC protection of CLL cells from fludarabine mediated cytotoxicity was negated in the presence of AT-101. Together our results describe a new therapeutic mechanism for targeting CLL interaction with the microenvironment. Specifically, a pan-inhibitor of Bcl-2 family anti-apoptotic proteins AT-101 antagonizes the protection of CLL by NLC to both spontaneous and fludarabine mediated apoptosis.

Glycovariant CD37 Small Modular Immuno-Pharmaceutical (TruADhanCe™ SMIP) Promotes Enhanced Natural Killer Cell Mediated Cytotoxicity against Primary Chronic Lymphocytic Leukemia Cells.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1744-1744
Author(s):  
Sarwish Rafiq ◽  
Carolyn Cheney ◽  
Peter A Thompson ◽  
Tony Siadak ◽  
Paul Algate ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Natural Killer ◽  
B Cell Lymphoma ◽  
Leukemia Cells ◽  
New Variant ◽  
Direct Cytotoxicity ◽  
Cross Linker

Abstract Abstract 1744 Poster Board I-770 CD37 is a tetraspanin transmembrane family protein that is strongly expressed on the surface of mature human B-cells and transformed mature B-cell lymphoma and leukemia cells, including CLL cells. It is expressed minimally or is absent on normal T-cells, natural killer cells, monocytes, and granulocytes. Predominant expression of CD37 on CLL cells makes it an ideal candidate to target with potential agents for treatment of CLL. TRU-016, a Small Modular ImmunoPharmaceutical protein (SMIP) targeted towards the extracellular region of CD37, is presently in clinical trials in CLL patients. TRU-016 consists of variable regions (scFv) and engineered constant regions encoding the human IgG1 domains. We have previously reported that SMIP-016, the chimeric precursor of the fully humanized TRU-016, induced apoptosis in CLL B cells in the presence of goat anti-human Fc ab cross-linker through a novel, caspase-independent pathway. Furthermore, SMIP-016 showed potent in-vivo activity in a SCID xenograft mouse model. Aside from direct cytotoxicity, SMIP-016 mediates antibody-dependent cellular cytotoxicity (ADCC) by NK cells both in vitro and in vivo. Recently, in an attempt to enhance the ADCC function, a new variant of SMIP-016, Tru-ADhanCe SMIP-016, has been created with a modification of the glycosylation of the Fc portion of the molecule. TRU-ADhanCe SMIP-016 has been shown to exhibit enhanced binding to both low- and high-affinity molecular variants of human CD16 (FcRIII) and augmented ADCC potency when compared to SMIP-016. In this study, we compared TruADhanCe SMIP-016 and SMIP-016 in direct cytotoxicity and ADCC experiments using CLL B-cells. While SMIP-016, and TruADhanCe SMIP-016 mediated comparable direct cytotoxicity at 24, 48 and 72 hrs in the presence of anti-human Fc crosslinker, the TruADhanCe SMIP-016 resulted in 2 to 4 fold increased NK cell mediated ADCC function. Consistent with the comparable direct cytotoxic effects, the early phosphorylation patterns were similar in cells treated with TruADhanCe SMIP-016 or SMIP-016 in the presence of anti-human Fc cross linker. Ongoing studies are aimed to define the mechanistic basis of the enhanced ADCC function by TruADhanCe SMIP-016 and to determine if use of soluble CD16.Fc as a cross-linker, an in vitro model of in vivo Fc receptor binding, may reveal enhanced apoptotic-signaling of TruADhanCe SMIP-016. These results suggest potential use of TruADhanCe versions of TRU-016 with enhanced ADCC function as an alternate for TRU-016 in B cell malignancies including CLL therapy. [This work was supported by D. Warren Brown Foundation, Leukemia and Lymphoma Society and National Cancer Institute.] Disclosures Thompson: Trubion Pharmaceuticals: Employment. Siadak:Trubion Pharmaceuticals: Employment. Algate:Trubion Pharmaceuticals: Employment. Cerveny:Trubion Pharmaceuticals: Employment.

A6 Peptide Is Selectively Cytotoxic For Chronic Lymphocytic Leukemia Cells

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 5303-5303
Author(s):  
Suping Zhang ◽  
Hsien Lai ◽  
Grace Liu ◽  
Laura Rassenti ◽  
Michael Y. Choi ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
B Cells ◽  
Chronic Lymphocytic Leukemia ◽  
Lymphocytic Leukemia ◽  
Surface Glycoprotein ◽  
Leukemia Cells ◽  
Dependent Manner ◽  
Cell Surface Glycoprotein

Abstract Chronic lymphocytic leukemia (CLL) cells express high levels of CD44, a cell-surface glycoprotein receptor for hyaluronic acid (HA). We found that a mAb specific for CD44 was directly cytotoxic for leukemia B cells, but had little effect on normal B cells. Moreover, this anti-CD44 mAb could induce CLL cells that expressed the zeta-associated protein of 70 kDa (ZAP-70) to undergo caspase-dependent apoptosis, independent of complement or cytotoxic effector cells (Proc Natl Acad Sci, USA 2013, PMID: 23530247). The cytotoxic effect of this mAb was not mitigated when the CLL cells were co-cultured with mesenchymal stromal cells (MSCs) or hyaluronic acid or when they were stimulated via ligation of the B-cell receptor with anti-µ. A6 (Angstrom Pharmaceuticals) is an 8-amino acid peptide that has marked homology with a linear sequence of CD44. A6 can bind CD44 within a region of the ligand-binding domain, leading to inhibition of the migration and metastatic potential of CD44-expressing cancer cells in vitro and in vivo (Mol Cancer Ther, 2011 PMID: 21885863). We evaluated the cytotoxic activity of A6 against primary leukemia cells of patients with CLL (n = 22). We found that A6 peptide also was directly cytotoxic for CLL cells isolated from different patients in a dose-dependent manner at concentrations that may be achieved in vivo. The A6 peptide appeared less cytotoxic for CLL cells than the intact anti-CD44 mAb, but still had greater direct cytotoxicity for CLL cells that expressed ZAP-70 than for CLL cells that were ZAP-70 negative. Furthermore, the A6 peptide had negligible effect on the viability of lymphocytes isolated from the blood of healthy donors (n = 3). Because clinical studies have found the A6 peptide to be well-tolerated and without dose-limiting toxicity in patients with solid tumors who have been treated to date (N = 40), a clinical study is planned to evaluate the safety and activity of the A6 peptide in the treatment of patients with CLL. Disclosures: Howell: Angstrom Phamaceuticals: Membership on an entity’s Board of Directors or advisory committees. Finlayson:Angstrom Phamaceuticals: Employment.

scholarly journals In vitro and in vivo effects of 3-bromopyruvate against Echinococcus metacestodes

2019 ◽  
Vol 50 (1) ◽  
Author(s):  
Qi Xin ◽  
Miaomiao Yuan ◽  
Huanping Li ◽  
Xiaoxia Song ◽  
Jun Lu ◽  
...  
Keyword(s):  
Energy Production ◽  
Alveolar Echinococcosis ◽  
Weekly Treatment ◽  
Significant Toxicity ◽  
Liver And Kidney ◽  
In Vitro Effects ◽  
In Vivo Effects ◽  
Dose Dependent

AbstractWhile searching for novel anti-echinococcosis drugs, we have been focusing on glycolysis which is relied on by Echinococcus for energy production and intermediates for other metabolic processes. The aim of this study was to investigate the potential therapeutic implication of glycolytic inhibitors on Echinococcus. Our results demonstrate that at an initial concentration of 40 μM, all inhibitors of glycolysis used in the current experiment [3-bromopyruvate (3-BrPA), ornidazole, clorsulon (CLS), sodium oxamate and 2,6-dihydroxynaphthalene (NA-P2)] show considerable in vitro effects against Echinococcus granulosus protoscoleces and Echinococcus multilocularis metacestodes. Among them, 3-BrPA exhibited the highest activity which was similar to that of nitazoxanide (NTZ) and more efficacious than albendazole (ABZ). The activity of 3-BrPA was dose dependent and resulted in severe ultrastructural destructions, as visualized by electron microscopy. An additional in vivo study in mice infected with E. multilocularis metacestodes indicates a reduction in parasite weight after the twice-weekly treatment of 25 mg/kg 3-BrPA for 6 weeks, compared to that of the untreated control. In particular, in contrast to ABZ, the administration of 25 mg/kg 3-BrPA did not cause toxicity to the liver and kidney in mice. Similarly, at the effective dose against Echinococcus larvae, 3-BrPA showed no significant toxicity to human hepatocytes. Taken together, the results suggest that interfering with the glycolysis of the parasite may be a novel chemotherapeutical option and 3-BrPA, which exhibited a remarkable activity against Echinococcus, may be a promising potential drug against cystic echinococcosis (CE) and alveolar echinococcosis (AE).

Effects of gluco- and antiglucocorticoids on renal and aortic prostaglandin synthesis

1986 ◽  
Vol 251 (5) ◽  
pp. F810-F816 ◽  
Author(s):  
J. P. Grunfeld ◽  
L. Eloy ◽  
A. Araujo ◽  
F. Russo-Marie
Keyword(s):  
Blood Pressure ◽  
Dependent Manner ◽  
Ru 486 ◽  
Pge2 Release ◽  
In Vivo Effects ◽  
Dose Dependent ◽  
Prostacyclin Production ◽  
Prostacyclin Synthesis

The effects of glucocorticoid agonists RU 26988 (G) and dexamethasone (D) and antagonist RU 486 (AG) on aortic and renal prostaglandin (PG) production were studied in Wistar rats. Blood pressure increased in rats administered G (20 mg X kg-1 X day-1) during 1 or 3 days; such increase was prevented by AG (100 mg X kg-1 X day-1). Renal papillary PGE2 release was increased after a 3-day administration of G, and this was prevented by AG. Neither G nor AG altered basal 6-keto-PGF1 alpha aortic production. However, G inhibited and AG magnified the stimulatory effect of ionophore A 23187, added in vitro, on 6-keto-PGF1 alpha production; AG reversed G inhibition. In addition, AG alone (20 mg X kg-1 X day-1 X 3 days) enhanced the stimulatory effect of angiotensin II (10(-8) M), added in vitro, on 6-keto-PGF1 alpha release. In vitro studies were performed on renomedullary interstitial cells grown in culture; G and D depressed PGE2 production in a dose-dependent manner; AG at equimolar 10(-8) M concentration inhibited this effect. In conclusion, AG inhibits the effects of G on blood pressure and PG synthesis. G exerts strong depressor activity on in vitro PGE2 renal production, whereas in vivo effects are more complex. Endogenous G inhibits aortic prostacyclin production, an action unmasked by AG administration. Diminished stimulation of vascular prostacyclin synthesis may contribute to vascular hyperreactivity in G-induced hypertension.

scholarly journals Dose-Dependent Outcome of EBV Infection of Humanized Mice Based on Green Raji Unit (GRU) Doses

Viruses ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2184
Author(s):  
Haiwen Chen ◽  
Ling Zhong ◽  
Wanlin Zhang ◽  
Shanshan Zhang ◽  
Junping Hong ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
Cd8 T Cells ◽  
Humanized Mice ◽  
High Dose ◽  
Ebv Infection ◽  
High Doses ◽  
Dose Dependent

Humanized mouse models are used as comprehensive small-animal models of EBV infection. Previously, infectious doses of EBV used in vivo have been determined mainly on the basis of TD50 (50% transforming dose), which is a time-consuming process. Here, we determined infectious doses of Akata-EBV-GFP using green Raji units (GRUs), and characterized dose-dependent effects in humanized mice. We defined two outcomes in vivo, including an infection model and a lymphoma model, following inoculation with low or high doses of Akata-EBV-GFP, respectively. Inoculation with a low dose induced primary B cells to become lymphoblastoid cell lines in vitro, and caused latent infection in humanized mice. In contrast, a high dose of Akata-EBV-GFP resulted in primary B cells death in vitro, and fatal B cell lymphomas in vivo. Following infection with high doses, the frequency of CD19+ B cells decreased, whereas the percentage of CD8+ T cells increased in peripheral blood and the spleen. At such doses, a small part of activated CD8+ T cells was EBV-specific CD8+ T cells. Thus, GRUs quantitation of Akata-EBV-GFP is an effective way to quantify infectious doses to study pathologies, immune response, and to assess (in vivo) the neutralizing activity of antibodies raised by immunization against EBV.

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