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1.
Arch Gynecol Obstet ; 309(5): 2057-2062, 2024 May.
Article En | MEDLINE | ID: mdl-38492083

PURPOSE: The objective of this study is to assess the correlation between bleeding irregularities and the accurate placement of the intrauterine device (IUD) device in the uterine cavity, determined through transvaginal ultrasonography and hysteroscopy. In addition, the study aims to examine the cytokine profile in the uterine cavity and serum of patients experiencing bleeding irregularities after the insertion of nonhormonal IUDs. METHODS: A prospective cohort study was conducted at a single tertiary medical center, wherein patients experiencing intermenstrual bleeding and spotting after the insertion of nonhormonal IUDs were enrolled. The study involved hysteroscopic and sonographic assessments of the uterine cavity and IUD placement, along with the analysis of blood and uterine cavity cytokine profiles. RESULTS: During the period between July 2019 and February 2020, a total of eight patients who experienced intermenstrual bleeding and spotting after the insertion of nonhormonal IUDs were enrolled the study. One case was excluded since a progestative device was detected by ultrasound. Out of the five cases that underwent a thorough ultrasonographic assessment, three cases (60%) showed an embedded IUD. However, these findings were excluded by the hysteroscopic evaluation. CONCLUSION: The results suggest that ultrasonographic assessment may lead to an overdiagnosis of IUD mispositioning compared to hysteroscopy. In addition, both ultrasound and hysteroscopy have limitations in diagnosing the cause of bleeding in most cases. The role of local reactive inflammatory cytokines should be further studied.


Intrauterine Devices , Menorrhagia , Metrorrhagia , Pregnancy , Humans , Female , Hysteroscopy , Menorrhagia/diagnostic imaging , Menorrhagia/etiology , Prospective Studies , Hemorrhage , Ultrasonography , Cytokines
3.
Front Immunol ; 12: 621440, 2021.
Article En | MEDLINE | ID: mdl-34248930

The risk of severe outcomes following respiratory tract infections is significantly increased in individuals over 60 years, especially in those with chronic medical conditions, i.e., hypertension, diabetes, cardiovascular disease, dementia, chronic respiratory disease, and cancer. Down Syndrome (DS), the most prevalent intellectual disability, is caused by trisomy-21 in ~1:750 live births worldwide. Over the past few decades, a substantial body of evidence has accumulated, pointing at the occurrence of alterations, impairments, and subsequently dysfunction of the various components of the immune system in individuals with DS. This associates with increased vulnerability to respiratory tract infections in this population, such as the influenza virus, respiratory syncytial virus, SARS-CoV-2 (COVID-19), and bacterial pneumonias. To emphasize this link, here we comprehensively review the immunobiology of DS and its contribution to higher susceptibility to severe illness and mortality from respiratory tract infections.


Down Syndrome/immunology , Immune System/physiology , Orthomyxoviridae/physiology , Respiratory Syncytial Viruses/physiology , Respiratory Tract Infections/immunology , SARS-CoV-2/physiology , Virus Diseases/immunology , Adult , Animals , COVID-19 , Down Syndrome/genetics , Down Syndrome/mortality , Humans , Pneumonia , Respiratory Tract Infections/genetics , Respiratory Tract Infections/mortality , Risk , Virus Diseases/genetics , Virus Diseases/mortality
5.
Neuromolecular Med ; 23(4): 561-571, 2021 12.
Article En | MEDLINE | ID: mdl-33660221

The current SARS-CoV-2 outbreak, which causes COVID-19, is particularly devastating for individuals with chronic medical conditions, in particular those with Down Syndrome (DS) who often exhibit a higher prevalence of respiratory tract infections, immune dysregulation and potential complications. The incidence of Alzheimer's disease (AD) is much higher in DS than in the general population, possibly increasing further the risk of COVID-19 infection and its complications. Here we provide a biological overview with regard to specific susceptibility of individuals with DS to SARS-CoV-2 infection as well as data from a recent survey on the prevalence of COVID-19 among them. We see an urgent need to protect people with DS, especially those with AD, from COVID-19 and future pandemics and focus on developing protective measures, which also include interventions by health systems worldwide for reducing the negative social effects of long-term isolation and increased periods of hospitalization.


COVID-19/epidemiology , COVID-19/virology , Disease Susceptibility , Down Syndrome/epidemiology , Adolescent , Adult , Alzheimer Disease/complications , Alzheimer Disease/epidemiology , Alzheimer Disease/immunology , COVID-19/complications , COVID-19/prevention & control , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , Comorbidity , Disease Susceptibility/immunology , Disease Susceptibility/virology , Down Syndrome/complications , Down Syndrome/immunology , Female , Hospitalization , Humans , Immune System/abnormalities , Incidence , Male , Pandemics/prevention & control , Prevalence , Risk Factors , Vaccination/methods
6.
Leuk Lymphoma ; 62(5): 1146-1156, 2021 05.
Article En | MEDLINE | ID: mdl-33334225

Multiple Myeloma, effectively treated by chemotherapeutic drugs, relapses due to drug resistance. We tested here the capacity of mesenchymal stromal cells, from the bone marrow of patients or from adipose tissue of healthy individuals, to induce drug resistance in Myeloma cell lines. We show that drug resistance can be achieved by factors secreted by the various MSC's. Mass spectrometry analysis of MSC's conditioned media revealed that fibronectin, was particularly instrumental in providing anti-apoptotic signals to MM cells. Moreover, we demonstrate that SAS ([octa-O-bis-(R,R)tartarate ditellurane]), an immunomodulator Tellurium compound, is not only able of blocking the physical interaction between MM cells and fibronectin but is also capable of re-sensitizing the cells to the chemotherapeutic drugs. Finally, we show that this re-sensitization is coupled with the blocking of pAKT induction, in MM cells, by the MSC's. These results indicate that SAS may be useful in the treatment of drug resistant MM.


Multiple Myeloma , Pharmaceutical Preparations , Bone Marrow , Drug Resistance, Neoplasm , Humans , Multiple Myeloma/drug therapy , Neoplasm Recurrence, Local , Tellurium/pharmacology
7.
Front Immunol ; 10: 979, 2019.
Article En | MEDLINE | ID: mdl-31191514

The study shows that treatment of NOD mice with either of two tellurium-based small molecules, AS101 [ammonium trichloro(dioxoethylene-o,o')tellurate] or SAS [octa-O-bis-(R,R)-tartarate ditellurane] could preserve ß cells function and mass. These beneficial effects were reflected in decreased incidence of diabetes, improved glucose clearance, preservation of body weight, and increased survival. The normal glucose levels were associated with increased insulin levels, preservation of ß cell mass and increased islet size. Importantly, this protective activity could be demonstrated when the compounds were administered either at the early pre-diabetic phase with no or initial insulitis, at the pre-diabetic stage with advanced insulitis, or even at the advanced, overtly diabetic stage. We further demonstrate that both tellurium compounds prevent migration of autoimmune lymphocytes to the pancreas, via inhibition of the α4ß7 integrin activity. Indeed, the decreased migration resulted in diminished pancreatic islets damage both with respect to their size, ß cell function, and caspase-3 activity, the hallmark of apoptosis. Most importantly, AS101 and SAS significantly elevated the number of T regulatory cells in the pancreas, thus potentially controlling the autoimmune process. We show that the compounds inhibit pancreatic caspase-1 activity followed by decreased levels of the inflammatory cytokines IL-1ß and IL-17 in the pancreas. These properties enable the compounds to increase the proportion of Tregs in the pancreatic lymph nodes. AS101 and SAS have been previously shown to regulate specific integrins through a unique redox mechanism. Our current results suggest that amelioration of disease in NOD mice by this unique mechanism is due to decreased infiltration of pancreatic islets combined with increased immune regulation, leading to decreased inflammation within the islets. As these tellurium compounds show remarkable lack of toxicity in clinical trials (AS101) and pre-clinical studies (SAS), they may be suitable for the treatment of type-1 diabetes.


Diabetes Mellitus, Type 1/drug therapy , Ethylenes/therapeutic use , Integrins/antagonists & inhibitors , Interleukin-1beta/antagonists & inhibitors , T-Lymphocytes, Regulatory/drug effects , Animals , Diabetes Mellitus, Type 1/immunology , Ethylenes/pharmacology , Female , Integrins/physiology , Interleukin-1beta/physiology , Mice , Mice, Inbred NOD , Pancreatitis/drug therapy , Th17 Cells/physiology
8.
J Autoimmun ; 100: 52-61, 2019 06.
Article En | MEDLINE | ID: mdl-30853312

AS101 is an organotellurium compound with multifaceted immunoregulatory properties that is remarkable for its lack of toxicity. We tested the therapeutic effect of AS101 in experimental autoimmune uveitis (EAU), a model for human autoimmune uveitis. Unexpectedly, treatment with AS101 elicited Treg generation in vivo in otherwise unmanipulated mice. Mice immunized for EAU with the retinal antigen IRBP and treated with AS101 developed attenuated disease, as did AS101-treated recipients of retina-specific T cells activated in vitro. In both settings, eye-infiltrating effector T cells were decreased, whereas regulatory T (Treg) cells in the spleen were increased. Mechanistic studies in vitro revealed that AS101 restricted polarization of retina-specific T cells towards Th1 or Th17 lineage by repressing activation of their respective lineage-specific transcription factors and downstream signals. Retina-specific T cells polarized in vitro towards Th1 or Th17 in the presence of AS101 had impaired ability to induce EAU in naïve recipients. Finally, AS101 promoted differentiation of retina-specific T cells to Tregs in vitro independently of TGF-ß. We conclude that AS101 modulates autoimmune T cells by inhibiting acquisition and expression of effector function and by promoting Treg generation, and suggest that AS101 could be useful as a therapeutic approach for autoimmune uveitis.


Autoimmune Diseases/drug therapy , Ethylenes/pharmacology , T-Lymphocytes, Regulatory/immunology , Th1 Cells/immunology , Th17 Cells/immunology , Uveitis/drug therapy , Animals , Autoimmune Diseases/genetics , Autoimmune Diseases/immunology , Autoimmune Diseases/pathology , Disease Models, Animal , Mice , Mice, Transgenic , T-Lymphocytes, Regulatory/pathology , Th1 Cells/pathology , Th17 Cells/pathology , Uveitis/genetics , Uveitis/immunology , Uveitis/pathology
9.
ACS Appl Bio Mater ; 2(5): 2246-2251, 2019 May 20.
Article En | MEDLINE | ID: mdl-35030663

The in vivo delivery of therapeutic nanoparticles (NPs) represents a potentially powerful tool that can significantly alter the biological effects of pharmaceutically active compounds. Here, we report on sensitization of tumors to chemotherapy by ammonium trichloro(dioxoethylene-o,o')tellurate (AS101) encapsulated in NPs, termed AS101-NPs, developed as a composite with the biocompatible and biodegradable copolymer of poly(d,l-lactic-co-glycolic acid)-block-poly(ethylene glycol) (PLGA-b-PEG). AS101 is a potent immunomodulating agent (both in vitro and in vivo) currently undergoing phase II clinical trials for antitumor activity and sensitization of tumors to chemotherapy. Approaches that can control the pharmacokinetic parameters to regulate its clearance from the administered drug delivery system and minimize side effects are of prodigious importance. A strategy to synthesize AS101-NPs by nanoprecipitation is presented, along with their physical characterization. The influence of AS101 encapsulation on its properties was evaluated in vivo. The AS101-NPs demonstrated a significantly enhanced peritoneal macrophage count compared with AS101 administered in vivo at a conventional dosage in mouse models. Moreover, AS101 inhibited B16 melanoma lung metastasis in mice when given intraperitoneally, before or after tumor cell inoculation. A bell-shaped dose-response was observed. The frequency of AS101 administration appears to be an important factor for achieving an optimal antimetastatic effect.

10.
Behav Pharmacol ; 28(6): 458-465, 2017 09.
Article En | MEDLINE | ID: mdl-28590303

Ammonium trichloro (dioxoethylene-O,O') tellurate (AS101) is a synthetic organotellurium compound with potent immunomodulatory and neuroprotective properties shown to inhibit the function of integrin αvß3, a presynaptic cell-surface-adhesion receptor. As partial deletion of αvß3 downregulated reuptake of serotonin by the serotonin transporter, we hypothesized that AS101 may influence pathways regulating anxiety. AS101 was tested in the modulation of anxiety-like behavior using the selectively bred Submissive (Sub) mouse strain that develop anxiety-like behavior in response to an i.p. injection. Mice were treated daily with AS101 (i.p., 125 or 200 µg/kg) or vehicle for 3 weeks, after which their anxiety-like behavior was measured in the elevated plus maze. Animals were then culled for the measurement of serum corticosterone levels by ELISA and hippocampal expression of brain-derived neurotrophic factor (BDNF) by RT-PCR. Chronic administration of AS101 significantly reduced anxiety-like behavior of Sub mice in the elevated plus maze, according to both time spent and entries to open arms, relative to vehicle-treated controls. AS101 also markedly reduced serum corticosterone levels of the treated mice and increased their hippocampal BDNF expression. Anxiolytic-like effects of AS101 may be attributed to the modulation of the regulatory influence integrin of αvß3 upon the serotonin transporter, suggesting a multifaceted mechanism by which AS101 buffers the hypothalamic-pituitary-adrenal axis response to injection stress, enabling recovery of hippocampal BDNF expression and anxiety-like behavior in Sub mice. Further studies should advance the potential of AS101 in the context of anxiety-related disorders.


Anxiety/drug therapy , Ethylenes/pharmacology , Ammonium Compounds , Animals , Anxiety/metabolism , Brain-Derived Neurotrophic Factor/metabolism , Corticosterone/analysis , Corticosterone/blood , Disease Models, Animal , Ethylenes/metabolism , Hypothalamo-Hypophyseal System/metabolism , Immunomodulation , Integrin alphaVbeta3/metabolism , Mice , Neuroprotective Agents , Pituitary-Adrenal System/metabolism , Tellurium
11.
Front Immunol ; 8: 240, 2017.
Article En | MEDLINE | ID: mdl-28326083

Crescentic glomerulonephritis (CGN) is the most aggressive form of GN and, if untreated, patients can progress to end-stage renal failure within weeks of presentation. The α4ß1 integrin very late antigen-4 (VLA-4) is an adhesion molecule of fundamental importance to the recruitment of leukocytes in inflammation. We addressed the role of VLA-4 in mediating progressive renal injury in a rat model of CGN using a small tellurium compound. AS101 [ammonium trichloro(dioxoethylene-o,o')tellurate]. This compound has been previously shown to uniquely inhibit VLA-4 activity by redox inactivation of adjacent thiols in the exofacial domain of VLA-4. The study shows that administration of AS101 either before or after glomerular basement membrane anti-serum injection ameliorates crescent formation or preserves renal function. This was associated with profound inhibition of critical inflammatory mediators, accompanied by decreased glomerular infiltration of macrophages. Mechanistic studies demonstrated vla-4 inactivation on glomerular macrophages both in vitro and in vivo as well as inhibition of caspase-1 activity. Importantly, this cysteine protease activity modification was dependent on VLA-4 inactivation and was associated with the anti-inflammatory activity of AS101. We propose that inactivation of macrophage VLA-4 by AS101 in vivo results in a decrease of inflammatory cytokines and chemokines produced in the glomeruli of diseased rats, resulting in decreased further macrophage recruitment and decreased extracellular matrix expansion. Thus, AS101, which is currently in clinical trials for other indications, might be beneficial for treatment of CGN.

12.
Inorg Chem ; 55(21): 10847-10850, 2016 Nov 07.
Article En | MEDLINE | ID: mdl-27726342

Since its first crystallization, the aqueous structure of the tellurium-containing experimental drug AS-101 has never been studied. We show that, under the aqueous conditions in which it is administered, AS-101 is subjected to an immediate ligand-substitution reaction with water, yielding a stable hydrolyzed oxide anion product that is identified, for the first time, to be TeOCl3-. Studying the structure of AS-101 in propylene glycol (PG), an alcoholic solvent often used for the topical and oral administration of AS-101, revealed the same phenomenon of ligand-substitution reaction between the alcoholic ligands. Upon exposure to water, the PG-substituted product is also hydrolyzed to the same tellurium(IV) oxide form, TeOCl3-.


Adjuvants, Immunologic/chemistry , Alcohols/chemistry , Ethylenes/chemistry , Water/chemistry , Adjuvants, Immunologic/administration & dosage , Ethylenes/administration & dosage , Humans , Hydrolysis , Ligands , Oxides/chemistry , Propylene Glycol/chemistry , Solubility , Solutions , Solvents/chemistry
13.
Mol Vis ; 22: 548-62, 2016.
Article En | MEDLINE | ID: mdl-27293373

PURPOSE: Pathological angiogenesis and chronic inflammation greatly contribute to the development of choroidal neovascularization (CNV) in chorioretinal diseases involving abnormal contact between retinal pigment epithelial (RPE) and endothelial cells (ECs), associated with Bruch's membrane rupture. We explored the ability of the small organotellurium compound octa-O-bis-(R,R)-tartarate ditellurane (SAS) to mitigate inflammatory processes in human RPE cells. METHODS: Cell adhesion assays and analyses of gene and protein expression were used to examine the effect of SAS on ARPE-19 cells or primary human RPE cells that were grown alone or in an RPE-EC co-culture. RESULTS: Adhesion assays showed that SAS inhibited αv integrins expressed on RPE cells. Co-cultures of RPE cells with ECs significantly reduced the gene expression of PEDF, as compared to RPE cells cultured alone. Both SAS and the anti-αvß3 antibody LM609 significantly enhanced the production of PEDF at both mRNA and protein levels in RPE cells. RPE cells co-cultured with EC exhibited increased gene expression of CXCL5, COX1, MMP2, IGF1, and IL8, all of which are involved in both angiogenesis and inflammation. The enhanced expression of these genes was greatly suppressed by SAS, but interestingly, remained unaffected by LM609. Zymography assay showed that SAS reduced the level of MMP-2 activity in RPE cells. We also found that SAS significantly suppressed IL-1ß-induced IL-6 expression and secretion from RPE cells by reducing the protein levels of phospho-IkappaBalpha (pIκBα). CONCLUSIONS: Our results suggest that SAS is a promising anti-inflammatory agent in RPE cells, and may be an effective therapeutic approach for controlling chorioretinal diseases.


Anti-Inflammatory Agents/pharmacology , Inflammation/prevention & control , Organometallic Compounds/pharmacology , Retinal Pigment Epithelium/drug effects , Tartrates/pharmacology , Cell Line , Chemokine CXCL5/metabolism , Coculture Techniques , Cyclooxygenase 1/metabolism , Electrophoresis, Polyacrylamide Gel , Endothelial Cells/cytology , Enzyme-Linked Immunosorbent Assay , Eye Proteins/genetics , Eye Proteins/metabolism , Humans , Inflammation/metabolism , Insulin-Like Growth Factor I/metabolism , Integrin alphaV/metabolism , Interleukin-8/metabolism , Matrix Metalloproteinase 2/metabolism , Nerve Growth Factors/genetics , Nerve Growth Factors/metabolism , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Retinal Pigment Epithelium/metabolism , Serpins/genetics , Serpins/metabolism , Tellurium/pharmacology , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
14.
Chembiochem ; 17(10): 918-27, 2016 05 17.
Article En | MEDLINE | ID: mdl-26991356

Organic Te(IV) compounds (organotelluranes) differing in their labile ligands exhibited anti-integrin activities in vitro and anti-metastatic properties in vivo. They underwent ligand substitution with l-cysteine, as a thiol model compound. Unlike inorganic Te(IV) compounds, the organotelluranes did not form a stable complex with cysteine, but rather immediately oxidized it. The organotelluranes inhibited integrin functions, such as adhesion, migration, and metalloproteinase secretion mediation in B16F10 murine melanoma cells. In comparison, a reduced derivative with no labile ligand inhibited adhesion of B16F10 cells to a significantly lower extent, thus pointing to the importance of the labile ligands of the Te(IV) atom. One of the organotelluranes inhibited circulating cancer cells in vivo, possibly by integrin inhibition. Our results extend the current knowledge on the reactivity and mechanism of organotelluranes with different labile ligands and highlight their clinical potential.


Integrins/metabolism , Organometallic Compounds/chemistry , Organometallic Compounds/pharmacology , Tellurium/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Adhesion/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Disease Models, Animal , Integrin alpha4beta1/antagonists & inhibitors , Integrin alpha4beta1/metabolism , Integrins/antagonists & inhibitors , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Liver Neoplasms/secondary , Magnetic Resonance Spectroscopy , Male , Mice , Mice, Inbred C57BL , Organometallic Compounds/therapeutic use , Protein Binding/drug effects , Transplantation, Homologous
15.
Mol Cancer Res ; 13(3): 411-22, 2015 Mar.
Article En | MEDLINE | ID: mdl-25351768

UNLABELLED: Cancer cell resistance to chemotherapy is a major concern in clinical oncology, resulting in increased tumor growth and decreased patient survival. Manipulation of apoptosis has emerged as a new therapeutic strategy to eliminate cancer cells. The focus of this study resides within a novel approach to target survivin, an integrator of both cell death and mitosis. This protein plays a pivotal role in the resistance of tumors to chemotherapy, especially to paclitaxel. The data herein demonstrate an indirect repression of survivin in both B- and T-cell lymphoma and human NHL by the nontoxic tellurium compound, AS101 [ammonium trichloro(dioxoethylene-o,o')tellurate], via inhibition of tumor autocrine IL10-STAT3-Survivin signaling. As a result of survivin abrogation, sensitization of lymphomas to paclitaxel or to Abraxane, the new albumin-stabilized nanoparticle formulation of paclitaxel, occurs both in vitro and in vivo. Importantly, inhibition of lymphoma cell IL10 secretion is mediated by inactivation of the VLA-4 integrin, recently shown to be an important target of AS101. This activity is followed by inhibition of the PI3K-AKT axis that mediates IL10 suppression. Because a wide variety of lymphomas and other tumor types express VLA-4 and secrete IL10 in an autocrine manner, inhibition of survivin with a small nontoxic agent has vast clinical significance in modulating chemosensitivity in many tumor types. IMPLICATIONS: Combination therapy with AS101 and paclitaxel has novel therapeutic potential targeting deregulated active pathways in lymphoma, overcoming endogenous resistance to apoptosis.


Antineoplastic Agents/administration & dosage , Ethylenes/administration & dosage , Lymphoma, B-Cell/drug therapy , Lymphoma, T-Cell/drug therapy , Paclitaxel/administration & dosage , Signal Transduction/drug effects , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Apoptosis , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Drug Synergism , Ethylenes/pharmacology , Humans , Inhibitor of Apoptosis Proteins/metabolism , Integrin alpha4beta1/metabolism , Interleukin-10/metabolism , Lymphoma, B-Cell/metabolism , Lymphoma, T-Cell/metabolism , Mice , Neoplasm Transplantation , Paclitaxel/pharmacology , Repressor Proteins/metabolism , Survivin
16.
Blood ; 125(8): 1292-301, 2015 Feb 19.
Article En | MEDLINE | ID: mdl-25533034

Children with Down syndrome (DS) are at increased risk for acute myeloid leukemias (ML-DS) characterized by mixed megakaryocytic and erythroid phenotype and by acquired mutations in the GATA1 gene resulting in a short GATA1s isoform. The chromosome 21 microRNA (miR)-125b cluster has been previously shown to cooperate with GATA1s in transformation of fetal hematopoietic progenitors. In this study, we report that the expression of miR-486-5p is increased in ML-DS compared with non-DS acute megakaryocytic leukemias (AMKLs). miR-486-5p is regulated by GATA1 and GATA1s that bind to the promoter of its host gene ANK1. miR-486-5p is highly expressed in mouse erythroid precursors and knockdown (KD) in ML-DS cells reduced their erythroid phenotype. Ectopic expression and KD of miR-486-5p in primary fetal liver hematopoietic progenitors demonstrated that miR-486-5p cooperates with Gata1s to enhance their self renewal. Consistent with its activation of AKT, overexpression and KD experiments showed its importance for growth and survival of human leukemic cells. Thus, miR-486-5p cooperates with GATA1s in supporting the growth and survival, and the aberrant erythroid phenotype of the megakaryocytic leukemias of DS.


Down Syndrome/genetics , Erythropoiesis/genetics , Leukemia, Myeloid, Acute/genetics , MicroRNAs/physiology , Animals , Cell Differentiation/genetics , Cell Proliferation/genetics , Cell Transformation, Neoplastic/genetics , Child, Preschool , Down Syndrome/complications , Down Syndrome/physiopathology , Erythroid Cells/metabolism , HEK293 Cells , Humans , K562 Cells , Leukemia, Myeloid, Acute/pathology , Megakaryocytes/physiology , Mice , Mice, Inbred C57BL , Mice, Transgenic , MicroRNAs/genetics , Tumor Cells, Cultured
17.
PLoS One ; 9(12): e114287, 2014.
Article En | MEDLINE | ID: mdl-25474550

Diabetic nephropathy (DN) is characterized by proliferation of mesangial cells, mesangial expansion, hypertrophy and extracellular matrix accumulation. Previous data have cross-linked PKB (AKT) to TGFß induced matrix modulation. The non-toxic compound AS101 has been previously shown to favorably affect renal pathology in various animal models and inhibits AKT activity in leukemic cells. Here, we studied the pharmacological properties of AS101 against the progression of rat DN and high glucose-induced mesangial dysfunction. In-vivo administration of AS101 to Streptozotocin injected rats didn't decreased blood glucose levels but ameliorated kidney hypotrophy, proteinuria and albuminuria and downregulated cortical kidney phosphorylation of AKT, GSK3ß and SMAD3. AS101 treatment of primary rat glomerular mesangial cells treated with high glucose significantly reduced their elevated proliferative ability, as assessed by XTT assay and cell cycle analysis. This reduction was associated with decreased levels of p-AKT, increased levels of PTEN and decreased p-GSK3ß and p-FoxO3a expression. Pharmacological inhibition of PI3K, mTORC1 and SMAD3 decreased HG-induced collagen accumulation, while inhibition of GSK3ß did not affect its elevated levels. AS101 also prevented HG-induced cell growth correlated to mTOR and (rp)S6 de-phosphorylation. Thus, pharmacological inhibition of the AKT downstream pathway by AS101 has clinical potential in alleviating the progression of diabetic nephropathy.


Diabetes Mellitus, Experimental/pathology , Diabetic Nephropathies/drug therapy , Oncogene Protein v-akt/biosynthesis , Signal Transduction/drug effects , Animals , Blood Glucose , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/genetics , Diabetic Nephropathies/genetics , Diabetic Nephropathies/pathology , Ethylenes/administration & dosage , Gene Expression/drug effects , Mesangial Cells/drug effects , Mesangial Cells/pathology , Oncogene Protein v-akt/genetics , PTEN Phosphohydrolase/biosynthesis , Phosphatidylinositol 3-Kinases/biosynthesis , Phosphatidylinositol 3-Kinases/genetics , Phosphorylation , Rats , Smad3 Protein/biosynthesis , Smad3 Protein/genetics , Transforming Growth Factor beta/biosynthesis
18.
Autoimmun Rev ; 13(12): 1230-5, 2014 Dec.
Article En | MEDLINE | ID: mdl-25153485

Tellurium is a rare element, which has been regarded as a non-essential trace element despite its relative abundance in the human body. The chemistry of tellurium supports a plethora of activities, but its biochemistry is not clearly established to date. The small tellurium(IV) compound, ammonium trichloro (dioxoethylene-o,o')tellurate (AS101) developed and initially investigated by us, is currently being evaluated in Phase II clinical trials in psoriasis patients. AS101 is the first tellurium compound to be tested for clinical efficacy. This compound is a potent immunomodulator both in vitro and in vivo with a variety of potential therapeutic applications. The present review will focus on the immunomodulatory properties of AS101, and specifically, its effects in mitigating autoimmune diseases. AS101 has several activities that act on the immune system, including: 1) its ability to reduce IL-17 levels and to inhibit the function of Th17 cells; 2) its specific unique redox-modulating activities enabling the inhibition of specific leukocyte integrins such as α4ß1 and α4ß7, that are pivotal for diapedesis of macrophages and CD4(+) T inflammatory/auto-reactive cells into the autoimmune tissues; and 3) its ability to enhance the activity of regulatory T cells (Treg). These activities coupled with its excellent safety profile suggest that AS101 may be a promising candidate for the management of autoimmune diseases.


Adjuvants, Immunologic/therapeutic use , Autoimmune Diseases/drug therapy , Ethylenes/therapeutic use , Animals , Humans , Interleukin-17/immunology , Psoriasis/drug therapy , Th17 Cells/immunology
19.
J Neuroimmunol ; 273(1-2): 31-41, 2014 Aug 15.
Article En | MEDLINE | ID: mdl-24975323

We reported that AS101 (organotellurium compound, trichloro(dioxoethylene-O,O') tellurate) inhibited the differentiation of Th17 cells and reduced the production of IL-17 and GM-CSF. In addition, AS101 promoted the production of IL-2 in activated T cells. Flow cytometric analysis showed that AS101 inhibited Th17 cell proliferation. AS101 blocked the activation of transcriptional factor NFAT, Stat3, and RORγt, and increased activation of Erk1/2, suggesting a mechanism of action of AS101. We further demonstrated that AS101 was effective in amelioration of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. Finally, by real-time PCR analysis we showed that AS101 reduces the IL-17, IFN-γ, GM-CSF, and IL-6 mRNA expression in inflammatory cells of spinal cords. Additionally, flow cytometry analysis also indicated that the CD4+ T cells and IL-17 and GM-CSF-producing cells were reduced in the spinal cords of AS101 treated mice compared to those treated with PBS.


Cytokines/metabolism , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Ethylenes/pharmacology , Ethylenes/therapeutic use , Animals , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/metabolism , Cell Polarity/drug effects , Cell Proliferation/drug effects , Cytokines/biosynthesis , Cytokines/immunology , Disease Models, Animal , Dose-Response Relationship, Drug , Encephalomyelitis, Autoimmune, Experimental/chemically induced , Encephalomyelitis, Autoimmune, Experimental/pathology , Female , Freund's Adjuvant/pharmacology , Immunologic Factors/pharmacology , Immunologic Factors/therapeutic use , Mice , Mice, Inbred C57BL , Myelin-Oligodendrocyte Glycoprotein/pharmacology , Oncogene Protein v-akt/metabolism , Peptide Fragments/pharmacology , Signal Transduction/drug effects , Signal Transduction/immunology , Spinal Cord/pathology , Th17 Cells/drug effects
20.
Cancer Res ; 74(11): 3092-103, 2014 Jun 01.
Article En | MEDLINE | ID: mdl-24699624

Interaction between the integrin VLA-4 on acute myelogenous leukemia (AML) cells with stromal fibronectin is a decisive factor in chemotherapeutic resistance. In this study, we provide a rationale for a drug repositioning strategy to blunt integrin activation in AML cells and restore their sensitivity to chemotherapy. Specifically, we demonstrate that the nontoxic tellurium compound AS101, currently being evaluated in clinical trials, can abrogate the acquired resistance of AML. Mechanistic investigations revealed that AS101 caused redox inactivation of adjacent thiols in the exofacial domain of VLA-4 after its ligation to stromal fibronectin. This effect triggered cytoskeletal conformational changes that decreased PI3K/Akt/Bcl2 signaling, an obligatory step in chemosensitization by AS101. In a mouse xenograft of AML derived from patient leukemic cells with high VLA-4 expression and activity, we demonstrated that AS101 abrogated drug resistance and prolonged survival in mice receiving chemotherapy. Decreased integrin activity was confirmed on AML cells in vivo. The chemosensitizing activity of AS101 persisted in hosts with defective adaptive and innate immunity, consistent with evidence that integrin deactivation was not mediated by heightening immune attack. Our findings provide a mechanistic rationale to reposition the experimental clinical agent, AS101, to degrade VLA-4-mediated chemoresistance and improve clinical responses in patients with AML.


Ethylenes/pharmacology , Integrin alpha4beta1/metabolism , Leukemia, Myeloid/drug therapy , Oxidation-Reduction/drug effects , Sulfhydryl Compounds/metabolism , Animals , Cell Death/drug effects , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Fibronectins/metabolism , HL-60 Cells , Humans , Integrin alpha4beta1/antagonists & inhibitors , Leukemia, Myeloid/metabolism , Male , Mice , Mice, SCID , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , U937 Cells , bcl-Associated Death Protein/metabolism
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