Ventolini G.,Texas Tech University Health Sciences Center |
Gygax S.E.,Texas Tech University Health Sciences Center |
Gygax S.E.,Womens Health Research Center |
Adelson M.E.,Texas Tech University Health Sciences Center |
And 3 more authors.
Medical Hypotheses | Year: 2013
Vulvodynia (vulvar pain syndrome) is a chronic multifactorial disease affecting almost 13. million women in the USA and can lead to morbidity and a reduced quality of life. We hypothesize that an initial microbiological insult in the vagina causes modifications in the biological vaginal milieu and/or an alteration on the lactobacilli flora. The vaginal milieu responds to the insult by developing an inflammatory reaction with abnormal cytokine production. These hypotheses were tested quantifying vaginal lactobacillus and cytokines, in patients with vulvodynia compared to matched healthy controls. Our preliminary data suggest a vaginal flora alteration and an immunological response involving Candida in patients with vulvodynia. Ongoing studies will assist us to clarify these findings. © 2013 Elsevier Ltd.
PubMed | Genesis Biotechnology Group and From the Institute of Metabolic Disorders and
Type: Journal Article | Journal: The Journal of biological chemistry | Year: 2015
AMP kinase is a heterotrimeric serine/threonine protein kinase that regulates a number of metabolic processes, including lipid biosynthesis and metabolism. AMP kinase activity is regulated by phosphorylation, and the kinases involved have been uncovered. The particular phosphatases counteracting these kinases remain elusive. Here we discovered that the protein phosphatase 2A heterotrimer, PP2A(Ppp2r2d), regulates the phosphorylation state of AMP kinase by dephosphorylating Thr-172, a residue that activates kinase activity when phosphorylated. Co-immunoprecipitation and co-localization studies indicated that PP2A(Ppp2r2d) directly interacted with AMP kinase. PP2A(Ppp2r2d) dephosphorylated Thr-172 in rat aortic and human vascular smooth muscle cells. A positive correlation existed between decreased phosphorylation, decreased acetyl-CoA carboxylase Acc1 phosphorylation, and sterol response element-binding protein 1c-dependent gene expression. PP2A(Ppp2r2d) protein expression was up-regulated in the aortas of mice fed a high fat diet, and the increased expression correlated with increased blood lipid levels. Finally, we found that the aortas of mice fed a high fat diet had decreased AMP kinase Thr-172 phosphorylation, and contained an Ampk-PP2A(Ppp2r2d) complex. Thus, PP2A(Ppp2r2d) may antagonize the aortic AMP kinase activity necessary for maintaining normal aortic lipid metabolism. Inhibiting PP2A(Ppp2r2d) or activating AMP kinase represents a potential pharmacological treatment for many lipid-related diseases.
News Article | March 1, 2017
HAMILTON, N.J., March 1, 2017 /PRNewswire/ -- Genesis Biotechnology Group (GBG), a consortium of an integrated group of biotechnology and research companies, announced that it has expanded its drug development services by the acquisition of PharmOptima. PharmOptima, a preclinical...
De Kruijf P.,VU University Amsterdam |
Lim H.D.,VU University Amsterdam |
Roumen L.,VU University Amsterdam |
Renjaan V.A.,VU University Amsterdam |
And 11 more authors.
Molecular Pharmacology | Year: 2011
We have shown previously that different chemical classes of small-molecule antagonists of the human chemokine CXCR2 receptor interact with distinct binding sites of the receptor. Although an intracellular binding site for diarylurea CXCR2 antagonists, such as N-(2-bromophenyl)-N′-(7-cyano-1H-benzotriazol- 4-yl)urea (SB265610), and thiazolopyrimidine compounds was recently mapped by mutagenesis studies, we now report on an imidazolylpyrimidine antagonist binding pocket in the transmembrane domain of CXCR2. Using different CXCR2 orthologs, chimeric proteins, site-directed mutagenesis, and in silico modeling, we have elucidated the binding mode of this antagonist. Our in silico-guided mutagenesis studies indicate that the ligand binding cavity for imidazolylpyrimidine compounds in CXCR2 is located between transmembrane (TM) helices 3 (Phe130 3.36), 5 (Ser217 5.44, Phe220 5.47), and 6 (Asn268 6.52, Leu271 6.55) and suggest that these antagonists enter CXCR2 via the TM5-TM6 interface. It is noteworthy that the same interface is postulated as the ligand entry channel in the opsin receptor and is occupied by lipid molecules in the recently solved crystal structure of the CXCR4 chemokine receptor, suggesting a general ligand entrance mechanism for nonpolar ligands to G protein-coupled receptors. The identification of a novel allosteric binding cavity in the TM domain of CXCR2, in addition to the previously identified intracellular binding site, shows the diversity in ligand recognition mechanisms by this receptor and offers new opportunities for the structure-based design of small allosteric modulators of CXCR2 in the future. Copyright © 2011 The American Society for Pharmacology and Experimental Therapeutics.
Yang M.,Institute of Metabolic Disorders |
Liu W.,Institute of Metabolic Disorders |
Pellicane C.,Institute of Metabolic Disorders |
Sahyoun C.,Institute of Metabolic Disorders |
And 7 more authors.
Journal of Lipid Research | Year: 2014
Dysregulation of cholesterol homeostasis is associated with various metabolic diseases, including atherosclerosis and type 2 diabetes. The sterol response element binding protein (SREBP)-2 transcription factor induces the expression of genes involved in de novo cholesterol biosynthesis and low density lipoprotein (LDL) uptake, thus it plays a crucial role in maintaining cholesterol homeostasis. Here, we found that overexpressing microRNA (miR)-185 in HepG2 cells repressed SREBP-2 expression and protein level. miR-185-directed inhibition caused decreased SREBP- 2-dependent gene expression, LDL uptake, and HMG-CoA reductase activity. In addition, we found that miR-185 expression was tightly regulated by SREBP-1c, through its binding to a single sterol response element in the miR-185 promoter. Moreover, we found that miR-185 expression levels were elevated in mice fed a high-fat diet, and this increase correlated with an increase in total cholesterol level and a decrease in SREBP-2 expression and protein. Finally, we found that individuals with high cholesterol had a 5-fold increase in serum miR-185 expression compared with control individuals. Thus, miR-185 controls cholesterol homeostasis through regulating SREBP-2 expression and activity. In turn, SREBP-1c regulates miR-185 expression through a complex cholesterol-responsive feedback loop. Thus, a novel axis regulating cholesterol homeostasis exists that exploits miR-185-dependent regulation of SREBP-2 and requires SREBP-1c for function. -Yang, M., W. Liu, C. Pellicane, C. Sahyoun, B. K. Joseph, C. Gallo-Ebert, M. Donigan, D. Pandya, C. Giordano, A. Bata, and J. T. Nickels, Jr. Identification of miR-185 as a regulator of de novo cholesterol biosynthesis and low density lipoprotein uptake. Copyright © 2014 by the American Society for Biochemistry and Molecular Biology, Inc..
Gallo-Ebert C.,Institute of Metabolic Disorders |
Donigan M.,Institute of Metabolic Disorders |
Stroke I.L.,Genesis Biotechnology Group |
Swanson R.N.,Genesis Biotechnology Group |
And 8 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2014
Infections by Candida albicans and related fungal pathogens pose a serious health problem for immunocompromised patients. Azole drugs, the most common agents used to combat infections, target the sterol biosynthetic pathway. Adaptation to azole therapy develops as drug-stressed cells compensate by upregulating several genes in the pathway, a process mediated in part by the Upc2 transcription factor. We have implemented a cell-based high-throughput screen to identify small-molecule inhibitorsof Upc2-dependent induction of sterol gene expression in response to azole drug treatment. The assay is designed to identify not only Upc2 DNA binding inhibitors but also compounds impeding the activation of gene expression by Upc2. An AlphaScreen assay was developed to determine whether the compounds identified interact directly with Upc2 and inhibit DNA binding. Three compounds identified by the cell-based assay inhibited Upc2 protein level and UPC2-LacZ gene expression in response to a block in sterol biosynthesis. The compounds were growth inhibitory and attenuated antifungal-induced sterol gene expression in vivo. They did so by reducing the level of Upc2 protein and Upc2 DNA binding in the presence of drug. The mechanism by which the compounds restrict Upc2 DNA binding is not through a direct interaction, as demonstrated by a lack of DNA binding inhibitory activity using the AlphaScreen assay. Rather, they likely inhibit a novel pathway activating Upc2 in response to a block in sterol biosynthesis. We suggest that the compounds identified represent potential precursors for the synthesis of novel antifungal drugs. © 2014, American Society for Microbiology.
McCourt P.,Genesis Biotechnology Group |
Gallo-Ebert C.,Genesis Biotechnology Group |
Gonghong Y.,University of Pittsburg |
Jiang Y.,University of Pittsburg |
Nickels J.T.,Genesis Biotechnology Group
Cell Cycle | Year: 2013
Maintaining accurate progression through the cell cycle requires the proper temporal expression and regulation of cyclins. The mammalian D-type cyclins promote G1-S transition. D1 cyclin protein stability is regulated through its ubiquitylation and resulting proteolysis catalyzed by the SCF E3 ubiquitin ligase complex containing the F-box protein, Fbx4. SCF E3-ligase-dependent ubiquitylation of D1 is trigged by an increase in the phosphorylation status of the cyclin. As inhibition of ubiquitin-dependent D1 degradation is seen in many human cancers, we set out to uncover how D-type cyclin phosphorylation is regulated. Here we show that in S. cerevisiae, a heterotrimeric protein phosphatase 2A (PP 2ACdc55) containing the mammalian PPP 2R2/PR55 B subunit ortholog Cdc55 regulates the stability of the G1 cyclin Cln2 by directly regulating its phosphorylation state. Cells lacking Cdc55 contain drastically reduced Cln2 levels caused by degradation due to cdk-dependent hyperphosphorylation, as a Cln2 mutant unable to be phosphorylated by the yeast cdk Cdc28 is highly stable in cdc55-null cells. Moreover, cdc55-null cells become inviable when the SCFGrr1 activity known to regulate Cln2 levels is eliminated or when Cln2 is overexpressed, indicating a critical relationship between SCF and PP 2A functions in regulating cell cycle progression through modulation of G1-S cyclin degradation/stability. In sum, our results indicate that PP 2A is absolutely required to maintain G1-S cyclin levels through modulating their phosphorylation status, an event necessary to properly transit through the cell cycle. © 2013 Landes Bioscience.
Gallo-Ebert C.,Genesis Biotechnology Group |
McCourt P.C.,Genesis Biotechnology Group |
Donigan M.,Genesis Biotechnology Group |
Villasmil M.L.,Genesis Biotechnology Group |
And 7 more authors.
Fungal Genetics and Biology | Year: 2012
The lipid transporter Arv1 regulates sterol trafficking, and glycosylphosphatidylinositol and sphingolipid biosyntheses in Saccharomyces cerevisiae. ScArv1 contains an Arv1 homology domain (AHD) that is conserved at the amino acid level in the pathogenic fungal species, Candida albicans and Candida glabrata. Here we show S. cerevisiae cells lacking Arv1 are highly susceptible to antifungal drugs. In the presence of drug, Scarv1 cells are unable to induce ERG gene expression, have an altered pleiotrophic drug response, and are defective in multi-drug resistance efflux pump expression. All phenotypes are remediated by ectopic expression of CaARV1 or CgARV1. The AHDs of these pathogenic fungi are required for specific drug tolerance, demonstrating conservation of function. In order to understand how Arv1 regulates antifungal susceptibility, we examined sterol trafficking. CaARV1/. CgARV1 expression suppressed the sterol trafficking defect of Scarv1 cells. Finally, we show that C. albicans arv1/arv1 cells are avirulent using a BALB/c disseminated mouse model. We suggest that overall cell survival in response to antifungal treatment requires the lipid transporter function of Arv1. © 2011 Elsevier Inc.