title: Spinal neuroimmune activation is independent of T-cell infiltration and attenuated by A3 adenosine receptor agonists in a model of oxaliplatin-induced peripheral neuropathy.
abstract: Many commonly used chemotherapeutics including oxaliplatin are associated with the development of a painful chemotherapy-induced peripheral neuropathy (CIPN). This dose-limiting complication can appear long after the completion of therapy causing a significant reduction in quality-of-life and impeding cancer treatment. We recently reported that activation of the Gi/Gq-coupled A3 adenosine receptor (A3AR) with selective A3AR agonists (i.e., IB-MECA) blocked the development of chemotherapy induced-neuropathic pain in models evoked by distinct agents including oxaliplatin without interfering with their anticancer activities. The mechanism(s) of action underlying these beneficial effects has yet to be explored. Our results herein demonstrate that the development of oxaliplatin-induced mechano-hypersensitivity (allodynia and hyperalgesia) in rats is associated with the hyperactivation of astrocytes, but not microglial cells, increased production of pro-inflammatory and neuroexcitatory cytokines (TNF, IL-1β), and reductions in the levels of anti-inflammatory/neuroprotective cytokines (IL-10, IL-4) in the dorsal horn of the spinal cord. These events did not require lymphocytic mobilization since oxaliplatin did not induce CD45(+)/CD3(+) T-cell infiltration into the spinal cord. A3AR agonists blocked the development of neuropathic pain with beneficial effects strongly associated with the modulation of spinal neuroinflammatory processes: attenuation of astrocytic hyperactivation, inhibition of TNF and IL-1β production, and an increase in IL-10 and IL-4. These results suggest that inhibition of an astrocyte-associated neuroinflammatory response contributes to the protective actions of A3AR signaling and continues to support the pharmacological basis for selective A3AR agonists as adjuncts to chemotherapeutic agents for the management of chronic pain.
authors.affiliation: Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Blvd, St. Louis, MO 63104, USA.
authors.forename: Kali
authors.initials: K
authors.lastname: Janes
authors.affiliation: Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Blvd, St. Louis, MO 63104, USA.
authors.forename: Carrie
authors.initials: C
authors.lastname: Wahlman
authors.affiliation: Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Blvd, St. Louis, MO 63104, USA.
authors.forename: Joshua W
authors.initials: JW
authors.lastname: Little
authors.affiliation: Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Blvd, St. Louis, MO 63104, USA.
authors.forename: Timothy
authors.initials: T
authors.lastname: Doyle
authors.affiliation: Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0810, USA.
authors.forename: Dillip K
authors.initials: DK
authors.lastname: Tosh
authors.affiliation: Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0810, USA.
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Jacobson
authors.affiliation: Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Blvd, St. Louis, MO 63104, USA. Electronic address: salvemd@slu.edu.
authors.forename: Daniela
authors.initials: D
authors.lastname: Salvemini
mesh_terms: D058909:Adenosine A3 Receptor Agonists / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D000970:Antineoplastic Agents / Q000633:toxicity*; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D006930:Hyperalgesia / Q000139:chemically induced / Q000517:prevention & control; D008297:Male; D009944:Organoplatinum Compounds / Q000633:toxicity*; D000077150:Oxaliplatin; D010523:Peripheral Nervous System Diseases / Q000139:chemically induced* / Q000276:immunology / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley; D066148:Spinal Cord Dorsal Horn / Q000187:drug effects / Q000276:immunology*; D013601:T-Lymphocytes / Q000502:physiology
chemical_list: D058909:Adenosine A3 Receptor Agonists; D000970:Antineoplastic Agents; D016207:Cytokines; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin
keywords: A3 adenosine receptor; Adenosine; Astrocytes; Chemotherapy-induced peripheral neuropathy; Neuroinflammation; Neuropathic pain; Oxaliplatin; Spinal cord