P.6.c. 003. The BDNF mimetic, GSB-106, produсes long-term analgesia and significant reduction of opiate withdrawal signs: comparison with dipeptide anxiolytic GB-115 effects in rats M.A. Konstantinopolsky ¹, T.A. Gudasheva ², L.G. Kolik ¹ V.V. Zakusov Institute of Pharmacology, ¹ Laboratory of Pharmacological Regulation of Addiction, ² Department of Medicinal Chemistry, Moscow, Russia [email protected] Introduction and Aim:. Antidepressants and Anxiolytics are used in clinical practice to eliminate the various features of opiate dependence. Some of them, benzodiazepine anxiolytics, especially, are able to produce the negative side effects [1]. New promising peptide origin medicines are safe and devoid of most disadvantages. Previously was shown, that cholecystokinin-4 (CCK-4) retro-analogue GB-115 (Ph|CH2|5-CO-Gly-L-Trp-NH2) exert anxiolytic-like activity and is capable to reduce the morphine withdrawal syndrome (WS) signs in rats [2,3], while the BDNF dipeptide mimetic GSB-106 [(bis-N-monosuccinil-seryl- lysine) hexamethylenediamide] exhibit antidepressant-like effect [4]. The present study has been initiated to investigate the potential antidepressant GSB-106 effects in comparison with those of anxiolytic GB-115 upon opiate WS, the pain thresholds and tolerance to morphine-induced analgesia in rats. The Methods. Incremental doses of morphine were injected i.p. to outbred male rats for 5 days followed by Naloxone (Du Pont De Nemours), 1mg/kg, to provoke acute WS. The peptides (GSB-106, 0.1-1.0 mg/kg; GB-115, 0.1-0.4 mg/kg;) have been injected i.p. 30 min before the test in the “open field” or daily 30 min before the morphine injections; after that the Total Index (TI) of WS was evaluated [5]. The pain thresholds in the water immersive «tail flick» test, in the «tail flick» and «hot plate» via “Ugo Basile apparatus”, the tolerance to morphine-induced analgesia were studied. Naltrexone (Sigma), 1mg/kg, i.p. was used to analyze the GSB-106 induced analgesia. Plantar tactile thresholds were measured in “von Frey” test. The acquisition of CPP after 5 days of morphine and GB- 115 injections on days 7 - 21-st were studied. For statistical assay Mann-Whitney-test, one way ANOVA and t-test were used. Catalepsy Tail flick & Hot plate Tests Rhinorrhea and nasal bleeding Flattening pose, ptosis, tonic seizures and writhing Morphine acute effects Signs of morphine withdrawal syndrome Dipeptide mimetic of THE BDNF CONFORMATION BDNF GSB-106 GB-115 Ph(CH2)5CO-Gly-Trp-NH2 OH H N NH2 HN O O O HN O OH O Von Frey test (tactile sensitivity test ) O HN O . H O O HN N NH2 H The influence of anxiolytic peptide GB-115 on «DA-related conception of addiction with HO possible neuropeptides involvement tolerance to morphine 180 Neuropeptides modulating effect StimulantsStimulants Effect of GSB-106 peptide on pain thresholds * * 160 + in tail flick test * VTA PFC *** 140 GABA -- DA * * n.accumbenc + Glut 160 *** * * * + 140 120 * * amygdala 120 Opiates Stimulants hippocampus 100 nicotine opiates 100 cannabis alcohol 80 80 60 modified from N. Latt et al. Addiction medicine, 2009 Dose (mg/kg) 60 40 Control (0,0) 40 20 GSB 106 (0,1) SUMMARY OF RESULTS level) the of base ( % threshold Pain 0 GSB-106 (1,0) 20 0,5 1 24 48 72 GB-115 in single doses eliminated individual features and decreased Time after injection, hours 0 TI of morphine WS by 38-46%, p < 0.05. Chronic administration of base of level) the ( % threshold Pain 30 min 45 min 30 min 45 min Effect of peptide GSB-106 upon the pain thresholds in 1-st day of experiment 5-th day of experiment morphine with GB-115 decreased the TI of WS by 29.8 – 35.7%, p < hot plate test Control GB-115 (o.1 ) morphine (2.0 ) GB-115 (0.1) + morphine ( 2.0 ) 0.05. GB-115 significantly increased analgesic action of morphine (up to *** *** *** 140 * - p < 0,05 ( Doses mg/kg ) ** * - p < 0,05 100 %, p < 0.01) and attenuated the tolerance to morphine by 23.8 %, p ** - p < 0,01 120 ** *** - p < 0,001 < 0.05. GSB-106 was more effective than GB-115, reducing the TI of WS 100 of the base level base ofthe Dose (mg/kg) % 80 Effect of GB-115 and GB-115+morphine by 55.2 - 45.6% (p < 0.001, p < 0.01) by single or chronic administration control (0,0) 60 combination on pain threshold in ‘tail flick test’ (0,1 mg/kg), correspondingly, in relation to “morphine+Naloxone” group. 40 GSB-106 (0,1) 450 GSB-106 significantly enhanced the pain thresholds in “tail flick” by * * 20 50,3% (p < 0.001) and in “hot plate” test by 28.8% (p < 0.01) at 24 h threshold, Pain GSB-106 (1,0) 400 * 0 Dose mg/kg point by low dose of 0.1 mg/kg. The peptide effect in “hot plate” test 0,5 1 24 48 72 350 1. control Time after injection, hours lasted 48 h at dose of 1.0 mg/kg. Antagonist of μ-opioid receptors 300 * 2. morphine (2.0) of the base of base level) the * * 3. GB-115 (0.1)+ GSB-106 and Naltrexone effect upon the pain % Naltrexone inhibited the peptide effect at 24 h point. The tactile ( 250 * morphine (2.0 ) thresholds in "tail flick" test 2 thresholds not changed significantly after GSB-106 was given to 160 4. GB-115 (0.1) *** 200 morphine-dependent rats: the thresholds recovered to the 34.5% level 140 Dose (mg/kg) 3 5. GB -115 (0.4) 120 ** *** ** ** * 150 6. GB -115 (1.0) control (0,0) 4 after single GSB-106 injection, comparing with “morphine + Naloxone” 100 1 of the base level base the of 100 % 80 5 p < 0,05 group level of 15.0 % (p = 0.08) and control as reference group (100 * - 60 GSB-106 ( 0,1) 50 6 %). 40 threshold Pain 0 20 GSB-106 (0,1)+ 15 30 45 60 90 120 min thresholds, Pain 0 NLTR (1,0) CONCLUSION 0,5 1 24 48 Time after injection, hours The influence of GSB-106 peptide Effect of chronic administration of GB-115 on tactile thresholds in Anxiolytic-like peptide, GB-115, and antidepressant-like peptide GSB- upon opiate WS in rats The influence of GSB-106 peptide on morphine-dependent rats 106, significantly decreased the morphine WS individual features and 2 behavioral signs of morphine WS 1,8 100 10 TI of WS. GB-106 effect was more profound. GB-115 significantly 1,6 90 * morphine chr+Nal ) 9 * 1,4 80 enhanced morphine analgesic action and attenuated the tolerance to 8 initial 1,2 70 scores ( value 7 morphine-induced analgesia. GB-106 had powerful, long-term vehicle+Nal 1 60 6 final analgesic effect at low systemic dose. GB-115, evidently, realizes its ## ** 0,8 50 5 ### ** 0,6 ### value ### ### 40 4 (grams) force Pressure *** *** actions by means of central CCK-receptors. Effects of GSB-106 maybe GSB- 0,4 *** *** 30 3 0,2 ***-Р < 0,001 106(once)+morph %) ( WS of Index Total a of Expression 20 mediated by interaction with BDNF (TrkB) - and opioid receptor 2 ### 0 ###-P < 0,001 chr+Nal 10 The Total Index ofWS Index Total The 1 1 2 3 4 systems of the brain. GSB-106 0 0 * chr+morph chr+Nal Experimental groups 1 2 3 4 Experimental groups References [1] Kelly T.M., Daley D.C., Douaihy A.B., 2012. Treatment of substance abusing patients with comorbid psychiatric disorders. Addict Behaviour, Jan;37(1):11-24. [2] Konstantinopolsky M.A., Chernjakova I.V., Gudasheva T.A. New cholecyctokinin-4 retro-analogue and dipeptide analogue of neurotensine as opiate dependence correctors: an experimental study. Europ.Neuropsychoparmacology, 21, (2), s168, (2011) [3] Konstantinopolsky M.A., Kolik L.G., T.A. Gudasheva. New peptide-opigin anxiolytics, GB-115 and Selank, as possible tools in treatment of opiate addiction: an experimental study. Eur. Neuropsychopharmacology,, vol. 24, suppl.2, s676-s677, (2014) [4] Gudasheva T.A., Tarasiuk A.V., Pomogaibo S.V., Logvinov I.O., Povarnina P.Yu., Antipova T.A., Seredenin S.B., 2012. Design and synthesis of dipeptide mimetics of brain-derived neurotrophic factor. Bioorg. Khim., 38(3): 280-290 [5] Konstantinopolsky M.A., Cherniakova I.V. Afobazole decreases severity of morphine withdrawal syndrome: experimental evidence,. Eksp. Klin. Farmakology, 74(10):12-6, (2011) Disclosure statement : there is not potential conflict of interest . .