cGMP Secreted From the Tapeworm Hymenolepis diminuta Is a Signal Molecule to the Host Intestine

• Published in: The Journal of parasitology Vol. 94; no. 4; pp. 771 - 779
• Main Authors: Zimmerman, Noah P, Brownfield, Mark S, DeVente, Jan, Bass, Paul, Oaks, John A
• Format: Journal Article
• Language: English
• Published: Lawrence, KS American Society of Parasitologists 01.08.2008; Allen Press Inc
• Subjects: Acids; Animals; Antibodies; Binding sites; Biochemistry-Physiology; Biological and medical sciences; Cell membranes; Cestoda; Colchicine; Colchicine - pharmacology; Cyclic GMP; Cyclic GMP - antagonists & inhibitors; Cyclic GMP - physiology; Cyclic GMP - secretion; Cyclic nucleotides; Cyclooxygenase Inhibitors - pharmacology; Cytoplasm; Cytoskeleton; Efflux; Enzyme-linked immunosorbent assay; Experiments; Fundamental and applied biological sciences. Psychology; General aspects; General aspects and techniques. Study of several systematic groups. Models; Humidity; Hymenolepis diminuta; Hymenolepis diminuta - drug effects; Hymenolepis diminuta - metabolism; Ileum - metabolism; Ileum - parasitology; Immunohistochemistry; Inhibitors; Intestinal motility; Intestine; Intestines; Invertebrates; Laboratories; Localization; Male; Molecules; Mucosa; Multidrug resistance; Nemathelminthia. Plathelmintha; Niflumic Acid - pharmacology; Nucleotides; Parasite hosts; Parasitology; Phosphodiesterase Inhibitors - pharmacology; Protein transport; Proteins; Purinones - pharmacology; Rats; Rats, Sprague-Dawley; Receptors; Secretion; Sheep; Smooth muscle; Sucrose; Tapeworms; Tegument; Tubulin Modulators - pharmacology; Worms; Zaprinast; United States > US; California; Michigan; Molecules; Helmintha; Parasite; Plathelmintha; Host; Cestoda; Invertebrata; Hymenolepis diminuta
• ISSN: 0022-3395; 1937-2345
• DOI: 10.1645/GE-1418.1

3′,5′-Cyclic guanosine monophosphate (cGMP), a well-known intracellular second messenger, is released to the intestinal lumen by the tapeworm, Hymenolepis diminuta. Enzyme-linked immunosorbent assay analysis of tapeworm conditioned media shows that cGMP is released at a constant rate. Multidrug resistant (MDR) proteins are efflux transporters for cyclic nucleotides. Two MDR inhibitors, niflumic acid and zaprinast, inhibit cGMP secretion by tapeworms and change the cGMP localization within the tapeworm tegument, as assessed by immunochemistry. cGMP, normally present throughout the tapeworm tegumental cytoplasm, is absent from the outer cytoplasmic band upon treatment with inhibitors. Inhibition of cGMP secretion by colchicine indicates that cGMP secretion is cytoskeleton dependent. Binding studies of [3H]cGMP to ileal segments of intestine demonstrate 2 saturable, reversible, and high-affinity binding sites. These studies demonstrate that cGMP is secreted from the cestode via a cytoskeleton-dependent mechanism and MDR efflux transporters. In addition, cGMP reaching the intestinal lumen can bind to the mucosa via receptors for cGMP. These data, combined with earlier observations of cGMP altering intestinal motility and slowing lumenal transit, indicate that tapeworms alter the physiology of the host digestive process via the secretion and binding of extracellular cGMP to lumenal receptors in the host intestine.