n-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl)benzamide and Disease-Models--Animal

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection

Chemotherapy-induced peripheral neuropathy is a serious adverse effect of chemotherapeutic agents such as paclitaxel. JTC-801, a nociceptin/orphanin FQ opioid peptide (NOP) receptor antagonist, has been reported to attenuate neuropathic pain in several pain models. However, the therapeutic significance and function of JTC-801 in chemotherapy-induced peripheral neuropathy remain unclear. In this study, we determined the effect of JTC-801 on neuropathic pain induced by paclitaxel, and we explored the potential mechanism in the dorsal root ganglion (DRG). The behavioral test showed that single or multiple systemic administrations of JTC-801 significantly alleviated mechanical allodynia in paclitaxel-treated rats. Using Western blot analysis and immunohistochemistry, we found that paclitaxel increased the expression of phosphatidylinositol 3-kinase (PI3K) and phospho-Akt (p-Akt) in the DRG. Double immunofluorescence staining indicated that p-Akt was expressed in neurons in the DRG. Multiple injections of JTC-801 significantly inhibited the activation of Akt and decreased the expression of inflammatory cytokines. The data suggest that JTC-801 alleviates mechanical allodynia associated with paclitaxel-induced neuropathic pain via the PI3K/Akt pathway.

Topics: Aminoquinolines; Analgesics; Animals; Behavior, Animal; Benzamides; Disease Models, Animal; Ganglia, Spinal; Hyperalgesia; Inflammation Mediators; Interleukin-1beta; Male; Narcotic Antagonists; Neuralgia; Nociceptin Receptor; Paclitaxel; Pain Threshold; Phosphatidylinositol 3-Kinase; Phosphorylation; Proto-Oncogene Proteins c-akt; Rats, Sprague-Dawley; Receptors, Opioid; Signal Transduction; Tumor Necrosis Factor-alpha

Single-prolonged stress (SPS), a rat model of post-traumatic stress disorder (PTSD), also induces long-lasting hyperalgesia associated with hypocortisolism and elevated nociceptin/orphanin FQ (N/OFQ) levels in serum and CSF. Here, we determined the effect of JTC-801 (N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl) benzamide monohydrochloride), a nociceptin/orphanin FQ peptide (NOP) receptor antagonist, on symptoms of pain and anxiety in rats after SPS exposure, and examined N/OFQ-NOP receptor system changes.. Male Sprague Dawley rats received JTC-801 (6 mg kg(-1) i.p., once daily) during days 7-21 of SPS. The ability of JTC-801 to inhibit N/OFQ-stimulated [(35) S]-GTPγS binding was confirmed in rat brain membranes. Anxiety-like behaviour and pain sensitivity were monitored by changes in elevated plus maze performance and withdrawal responses to thermal and mechanical stimuli. Serum corticosterone and N/OFQ content in CSF, serum and brain tissues were determined by radioimmunoassay; NOP receptor protein and gene expression in amygdala, hippocampus and periaqueductal grey (PAG) were examined by immunoblotting and real-time PCR respectively.. JTC-801 treatment reversed SPS-induced mechanical allodynia, thermal hyperalgesia, anxiety-like behaviour and hypocortisolism. Elevated N/OFQ levels in serum, CSF, PAG and hippocampus at day 21 of SPS were blocked by JTC-801; daily JTC-801 treatment also reversed NOP receptor protein and mRNA up-regulation in amygdala and PAG.. JTC-801 reversed SPS-induced anxiety- and pain-like behaviours, and NOP receptor system up-regulation. These findings suggest that N/OFQ plays an important role in hyperalgesia and allodynia maintenance after SPS. NOP receptor antagonists may provide effective treatment for co-morbid PTSD and pain.. This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.

Topics: Aminoquinolines; Amygdala; Animals; Anxiety; Benzamides; Disease Models, Animal; Hippocampus; Hot Temperature; Hyperalgesia; Male; Narcotic Antagonists; Nociceptin; Nociceptin Receptor; Opioid Peptides; Pain; Periaqueductal Gray; Rats, Sprague-Dawley; Receptors, Opioid; Stress Disorders, Post-Traumatic

Buprenorphine displays attributes of opioids, but also some features distinct from them. We examined spinal and supraspinal signal transduction of buprenorphine-induced anti-nociception in mice compared with morphine and fentanyl.. The opioid receptor antagonist naloxone, Pertussis toxin (PTX), G(z) protein antisense and nociceptin/orphanin-FQ receptor agonist nociceptin, and antagonist, JTC-801, were injected supraspinally (intracerebroventricular) and spinally (intrathecal). Also the cell-permeable Ser/Thr protein phosphatase inhibitor okadaic acid was given supraspinally.. Spinal naloxone (20 microg) or PTX (1 microg) attenuated morphine, fentanyl and buprenorphine (s.c.) anti-nociception. Supraspinal naloxone or PTX attenuated morphine and fentanyl, but not buprenorphine anti-nociception. Spinal G(z) protein antisense did not alter buprenorphine, morphine or fentanyl anti-nociception and supraspinal G(z)-antisense did not alter morphine or fentanyl anti-nociception. However, supraspinal G(z)-antisense (not random sense) reduced buprenorphine anti-nociception. Peripheral JTC-801 (1 mgxkg(-1), i.p.) enhanced the ascending (3 mgxkg(-1)) and descending (30 mgxkg(-1)) portions of buprenorphine's dose-response curve, but only spinal, not supraspinal, nociceptin (10 nmolxL(-1)) enhanced buprenorphine anti-nociception. Intracereboventricular okadaic acid (0.001-10 pg) produced a biphasic low-dose attenuation, high-dose enhancement of buprenorphine(3 or 30 mgxkg(-1), s.c.) anti-nociception, but did not affect morphine or fentanyl anti-nociception.. Buprenorphine has an opioid component to its supraspinal mechanism of analgesic action. Our present results reveal an additional supraspinal component insensitive to naloxone, PTX and nociceptin/orphanin-FQ, but involving G(z) protein and Ser/Thr protein phosphatase. These data might help explain the unique preclinical and clinical profiles of buprenorphine.

Topics: Acetylcholine; Adrenergic alpha-Antagonists; Aminoquinolines; Analgesics, Opioid; Anesthetics, Local; Animals; Benzamides; Brain; Buprenorphine; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Inhibitors; Fentanyl; GTP-Binding Proteins; Injections, Intraventricular; Injections, Spinal; Male; Mice; Morphine; Naloxone; Narcotic Antagonists; Nociceptin; Nociceptin Receptor; Okadaic Acid; Oligonucleotides, Antisense; Opioid Peptides; Pain; Pain Measurement; Pain Threshold; Pertussis Toxin; Phosphoprotein Phosphatases; Piperazines; Pyridines; Receptor, Serotonin, 5-HT1A; Receptors, Opioid; Serotonin 5-HT1 Receptor Antagonists; Serotonin Antagonists; Signal Transduction; Yohimbine

JTC-801, a nociceptin antagonist, may alleviate neuropathic pain because nociceptin has been shown to produce pain modulation. We report that JTC-801 alleviates heat-evoked hyperalgesia and investigated the possible protective effect on osteoporosis induced by chronic constriction injury (CCI) in rats. JTC-801 was given orally to rats with CCI at 0% (vehicle), 0.03% (low dose), or 0.06% (high dose) in food. Paw withdrawal latency (PWL) to heat, bone mineral content (BMC) and bone mineral density (BMD) of the whole tibial bone were measured. JTC-801 dose-dependently normalized PWL. Although JTC-801 did not inhibit a CCI-induced decrease in BMC and BMD, it inhibited an increase in the number of osteoclasts in the JTC-801 groups. JTC-801, given orally in food, alleviated heat-evoked hyperalgesia in CCI rats, suggesting that it is useful for the treatment of neuropathic pain.

Topics: Aminoquinolines; Animals; Benzamides; Disease Models, Animal; Hyperalgesia; Male; Nociceptin; Opioid Peptides; Pain Measurement; Rats; Rats, Sprague-Dawley