The Susceptibility of Trypanosomatid Pathogens to PI3/mTOR Kinase Inhibitors Affords a New Opportunity for Drug Repurposing

In our study we describe the potency of established phosphoinositide-3-kinase (PI3K) and mammalian Target of Rapamycin (mTOR) kinase inhibitors against three trypanosomatid parasites: Trypanosoma brucei, T. cruzi, and Leishmania sp., which are the causative agents for African sleeping sickness, Chagas disease, and leishmaniases, respectively. We noted that these parasites and humans express similar kinase enzymes. Since these similar human targets have been pursued by the drug industry for many years in the discovery of cellular growth and proliferation inhibitors, compounds developed as human anti-cancer agents should also have effect on inhibiting growth and proliferation of the parasites. With that in mind, we selected eight established PI3K and mTOR inhibitors for profiling against these pathogens. Among these inhibitors is an advanced clinical candidate against cancer, NVP-BEZ235, which we demonstrate to be a highly potent trypanocide in parasite cultures, and in a mouse model of T. brucei infection. Additionally, we describe observations of these inhibitors' effects on parasite growth and other cellular characteristics

NK-CD11c+ Cell Crosstalk in Diabetes Enhances IL-6-Mediated Inflammation during Mycobacterium tuberculosis Infection

In this study, we developed a mouse model of type 2 diabetes mellitus (T2DM) using streptozotocin and nicotinamide and identified factors that increase susceptibility of T2DM mice to infection by Mycobacterium tuberculosis (Mtb). All Mtb-infected T2DM mice and 40% of uninfected T2DM mice died within 10 months, whereas all control mice survived. In Mtb-infected mice, T2DM increased the bacterial burden and pro- and anti-inflammatory cytokine and chemokine production in the lungs relative to those in uninfected T2DM mice and infected control mice. Levels of IL-6 also increased. Anti-IL-6 monoclonal antibody treatment of Mtb-infected acute- and chronic-T2DM mice increased survival (to 100%) and reduced pro- and anti-inflammatory cytokine expression. CD11c+ cells were the major source of IL-6 in Mtb-infected T2DM mice. Pulmonary natural killer (NK) cells in Mtb-infected T2DM mice further increased IL-6 production by autologous CD11c+ cells through their activating receptors. Anti-NK1.1 antibody treatment of Mtb-infected acute-T2DM mice increased survival and reduced pro- and anti-inflammatory cytokine expression. Furthermore, IL-6 increased inflammatory cytokine production by T lymphocytes in pulmonary tuberculosis patients with T2DM. Overall, the results suggest that NK-CD11c+ cell interactions increase IL-6 production, which in turn drives the pathological immune response and mortality associated with Mtb infection in diabetic mice

A New Synthetic Approach to C-2-Symmetric Octacyclic Cage Diol via Claisen Rearrangement and Ring-Closing Metathesis as Key Steps

A simple synthetic strategy to C-2-symmetric bisannulated octacyclic novel cage diol 20 is reported in eight linear steps starting with a readily available 1,4-hydroquinone 22. Here, an atom economic processes such as Claisen rearrangement, Diels-Alder reaction, intramolecular [2+2] photocycloaddition and ring-closing metathesis (RCM) were used as key steps. The synthetic approach demonstrated here opensup new opportunities to assembled highly functionalized complex cage molecules that are difficult to realize by conventional routes. The structure of the RCM product 19 was firmly established on the basis of single-crystal X-ray diffraction studies

Design and synthesis of polycyclic bisindoles via Fischer indolization and ring-closing metathesis as key steps

Several bisindoles have been synthesized starting with a readily available tetracyclic dione via Fischer indolization and ring-closing metathesis as key steps. The Fischer indolization was achieved under deep eutectic reaction conditions using L-tartaric acid and dimethyl urea (30:70). Various indole derivatives synthesized here are C-2-symmetrical in nature. Due to binding ability, most of the C-2-symmetrical indole moieties exhibit inhibitory activities against to HIV-1 protease, Gram-positive bacteria Bacillus subtilis and Micrococcus luteus. These C-2-symmetric new chemical entities play a special role in medicinal chemistry. (C) 2016 Elsevier Ltd. All rights reserved

Spiro[cyclopentane-1,11′-hexacyclo[7.6.0.01,6.06,13.08,12.010,14]pentadecane]-7′,15′-dione

An unusual rearrangement of spiro cage dione to a trishomocubane derivatives is reported by acid-catalysed rearrangement with the aid of BF3·OEt2 in benzene (solvent) reflux conditions. Here, the molecular structure of cage molecule C19H22O2 (major product) consists of five-membered rings, which adopt an envelope conformation and six-membered rings adopt a chair or boat conformation. The Cremer & Pople puckering parameters of all four six-membered rings are calculated

c-Jun N-terminal kinase 1 defective CD4+CD25+FoxP3+ cells prolong pancreatic allograft survival in type 1 diabetic mice

Abstract CD4+CD25+FoxP3+ cells (Tregs) inhibit inflammatory immune responses to allografts. Here we found that co-transplantation of allogeneic pancreatic islets with Tregs that are defective in JNK1 signaling prolong the islet allograft survival in the liver parenchyma of the T1D mice. Deletion of the JNK1 in Tregs increased the expression of anti-apoptotic molecules Mcl-1, Bcl-Xl and anti-inflammatory cytokine IL-10 production. JNK1−/− Tregs persist for long period in the transplanted liver and prolong the islet allograft survival compared to WT Tregs. JNK1−/− Tregs demonstrated improved control of allo-inflammation compared to WT Tregs in the T1D liver upon co-transplantation. JNK1−/− Tregs specifically inhibit IL-17 and IL-21 medited alloimmune response. Inhibition of alloimmune response by JNK1−/− Tregs independently mediated through the LAG3 on its cell surface and the increased production of IL-10. Our study identifies a novel role of JNK1 signaling in the Tregs function and co-transplantation of JNK1 deficient Tregs enhances the islet allograft survival in the liver parenchyma of T1D mice.</jats:p

A TLR9 agonist promotes IL-22-dependent pancreatic islet allograft survival in type 1 diabetic mice

AbstractPancreatic islet transplantation is a promising potential cure for type 1 diabetes (T1D). Islet allografts can survive long term in the liver parenchyma. Here we show that liver NK1.1+ cells induce allograft tolerance in a T1D mouse model. The tolerogenic effects of NK1.1+ cells are mediated through IL-22 production, which enhances allograft survival and increases insulin secretion. Increased expression of NKG2A by liver NK1.1+ cells in islet allograft-transplanted mice is involved in the production of IL-22 and in the reduced inflammatory response to allografts. Vaccination of T1D mice with a CpG oligonucleotide TLR9 agonist (ODN 1585) enhances expansion of IL-22-producing CD3-NK1.1+ cells in the liver and prolongs allograft survival. Our study identifies a role for liver NK1.1+ cells, IL-22 and CpG oligonucleotides in the induction of tolerance to islet allografts in the liver parenchyma.</jats:p