- Email: [email protected]
P.1.g.048 Blockade of CB1 cannabinoid receptors and activation of CB2 interact to prevent cocaine-responses
P.1.g. Basic and clinical neuroscience − Neuropharmacology selective serotonin reuptake inhibitor (SSRI) paroxetine [1−3]. (Pre)clinical research suggests that neuroinflammation is linked to these alterations in fatty acid metabolism and amygdala-reactivity, which may also explain their association with antidepressant response [4]. Purpose: To test (I) alterations in (neuro)inflammation and its associations with fatty acid metabolism and amygdala-reactivity in MDD-patients compared to controls, and (II) whether these alterations predict prospective paroxetine response. Methods: We included 70 unmedicated MDD-patients and compared them with 51 matched healthy controls at baseline. We measured serum (high-sensitivity) C-reactive protein (CRP) as a measure for inflammation, and its associations with red blood cell membrane fatty acids, and in a subgroup amygdalareactivity to emotional faces using functional magnetic resonance imaging (fMRI). Subsequently, we treated the MDD-patients open label for 6 weeks with 20 mg/day paroxetine, and repeated baseline biological measures after 6 and 12 weeks. Finally, we compared (associations between) the biological measures between non-responders, early-responders (response at 6 weeks), and lateresponders (response at 12 weeks) [5]. We performed analyses using bootstrapping in linear mixed models and ordinal regression in SPSS 22 (IBM). Results: Compared to controls, MDD-patients showed higher CRP-concentrations after adjustment for confounders (P = 0.016). CRP was neither significantly associated with fatty acid metabolism nor amygdala-reactivity, and these relations did not differ between patients and controls. However, patients differed from controls in the association between omega-6 fatty acid arachidonic acid (AA) and left amygdala-reactivity, i.e. patients showed a more negative relation than controls (P = 0.014). CRP also predicted antidepressant response: early responders showed significantly higher CRP concentrations than non-responders throughout the study (P = 0.014). Finally, while the association between CRP and fatty acid metabolism did not predict response, the association between fatty acid metabolism [eicosapentaenoic acid (EPA)/AA-ratio] and left amygdala-reactivity was predictive of response (P = 0.029). Conclusion: Higher observed CRP-concentrations confirm a role for (neuro)inflammation in MDD. Against our hypotheses, this higher CRP was not associated with earlier described proinflammatory changes in fatty acid metabolism or increased amygdala-reactivity. However, the differential association between arachidonic acid and amygdala-reactivity in patients versus controls suggest that fatty acids may influence brain functioning through an alternative pathway. Interestingly, the association between CRP and antidepressant response was opposite to our expectations: early response was predicted by higher CRPconcentrations. This may suggest a specific inflammatory characterized MDD-subtype with a beneficial prognosis. The finding that the association between fatty acid metabolism and left amygdalareactivity was predictive of response deserves further study. In sum, different patterns of alterations in (associations between) biological measures may predict antidepressant response. Future studies in independent samples should continue to test the clinical applicability of these biological predictors for treatment response, e.g. using machine learning in a precision/personalized medicine approach. References [1] Mocking, R.J.T., Ruh´e, H.G., Westerink, A.M., Assies, J., Vaz, F.M., Koeter, M.W.J., Schene, A.H., 2014. Longitudinal interplay between
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[3]
[4]
[5]
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paroxetine and fatty acid metabolism in recovery from major depressive disorder. Eur Neuropsychopharmacol 24, S56-S57. Ruh´e, H.G., Booij, J., Veltman, D.J., Michel, M.C., Schene, A.H., 2012. Successful pharmacologic treatment of major depressive disorder attenuates amygdala activation to negative facial expressions: a functional magnetic resonance imaging study. J Clin Psychiatry 73, 451−9. Mocking, R.J., Verburg, H.F., Westerink, A.M., Assies, J., Vaz, F.M., Koeter, M.W.J., Ruh´e, H.G., Schene, A.H. Fatty acid metabolism and its longitudinal relationship with the hypothalamic-pituitary-adrenal axis in major depression: associations with prospective antidepressant response. Psychoneuroendocrinology 59, 1−13. Assies, J., Mocking, R.J., Lok, A., Ruh´e, H.G., Pouwer, F., Schene, A.H., 2014. Effects of oxidative stress on fatty acid- and onecarbon-metabolism in psychiatric and cardiovascular disease comorbidity. Acta Psychiatr Scand 130, 163−80. Ruh´e, H.G., Khoenkhoen, S.J., Ottenhof, K.W., Koeter, M.W., Mocking, R.J., Schene, A.H., 2015. Longitudinal effects of the SSRI paroxetine on salivary cortisol in Major Depressive Disorder. Psychoneuroendocrinology 52, 261−71.
P.1.g.048 Blockade of CB1 cannabinoid receptors and activation of CB2 interact to prevent cocaine-responses P. Gobira1 ° , F. Moreira1 1 Federal University of Minas gerais, Pharmacology, Belo Horizonte, Brazil Introduction: Type-one (CB1-R) and type-two (CB2-R) cannabinoid receptors are responsible for the pharmacological effects of D-9-tetrahydrocannabinol, the main active compound from Cannabis sativa. Their endogenous ligands, termed endocannabinoids, act upon the brain dopaminergic mesocorticolimbic system, which is directly or indirectly targeted by most addictive drugs. The possible interactions between CB1-R and CB2-R, however, have remained to be investigated. Thus, this study was designed to test the hypothesis that CB1 blockade shifts endocannabinoid actions to CB2-R and inhibits cocaine-induced hyperlocomotion. Methods and Results: Male Swiss mice (n = 7−10/group) received systemic injections of compounds acting on CB1-R and CB2-R followed by cocaine (20 mg/kg). The total distance travelled was recorded in an arena and analyzed by ANOVA followed by Newman-Keuls test. A two-way repeated-measures ANOVA followed by Bonferroni post hoc was used to analyze the differences in Conditioneted Place Preference (CPP) scores among the test conditions. First, we tested whether the CB1-R blockade prevents cocaine-induced hyperlocomotion and found that the antagonist, rimonabant (1, 3 and 10 mg/kg), was effective at the higher dose. Then, we investigated if this compound would act by shifting endocannabinoid actions to CB2-R. In line with our hypothesis, the CB2-R antagonist, AM 630 (10 and 20 mg/kg), reversed the effects of rimonabant (10 mg/kg). Then we tested if our hypothesis also extended to effects of cocaine induced c-Fos expression in the nucleus accubens, core and shell. We found that Rimonabant (10 mg/kg) attenuated the increasing in cFos expression induced by cocaine, in both region. Furthermore, in line with behavioral results previously exposed, the pretreatment with AM 630 reverses this effect of Rimonabant. To further explore the role of CB2-R, we tested if its activation would mimic the effect of CB1-R blockade. Indeed, the higher dose of the selective agonist, JWH-133 (5, 10 and 20 mg/kg), prevented cocaine-induced hyperlocomotion. We also demonstrated that rimonabant and JWH-133 were also effective when combined at sub-threshold doses (3 and 10 mg/kg). To investigate which endocannabinoid would be involved in this effect,we tested the effect of inhibition of endocannabinoids hydrolysis in cocaine-induced
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hyperlocomotion. Hydrolysis inhibition of anandamide and 2-AG didn’t inhibited cocaine-action. However when combined with a subthreshold dose of rimonabant, hydrolysis inhibition of 2-AG attenuated cocaine-hyperlocomotion. None of the compounds induced changes in basal locomotion. Finally we test if this interaction between cannabinoid receptors in conditioned place preference (CPP) protocol. As expected Rimonabanto(10 mg/kg) innibited the acquisition of cocaine-induced CPP. Confirming our hypothesis the CB2-R antagonist reversed this rimonabanto-effect. Conclusion: Our results demonstrate that CB1-R blockade and CB2-R activation interact to prevent cocaine-induced hyperlocomotion. We also showed that 2-AG has a important role in this process. In conclusion we proposed that blockade of CB1 receptor redirects 2Ag action to CB2 receptor, and the activation of this last is responsible by prevent cocaine-response. This represents a possible mechanism through which the endocannabinoid system modulates the effects of this psychostimulant drug.
(F(2,27) = 12.09, p = 0.0002). Obese rats exhibited more immobility than control group (p < 0.001), while there was no difference between control and etanercept-treated group (p > 0.05). Sucrose consumption in obese group was significantly lower than the control group (p < 0.05). However, there was no significant difference between etanercept-treated and control group in terms of sucrose consumption (p > 0.05). In sucrose preference test, the obese group preferred sucrose less than control group (p < 0.0001) and the behavior of rats in etanercept-treated group did not differ significantly from the control group (p > 0.05). Conclusions: The results of present study indicated that chronic etanercept treatment decreased depressive-like behavior in CD-fed rats, indicating that TNF-a may play a crucial role in obesityrelated depression. The data strongly suggest that etanercept may be useful in clinical practice as an antidepressant drug moreover its co-administration with antidepressant drugs may potentiate their clinical efficacy in patients. References
P.1.g.049 Chronic etanercept treatment exerts antidepressant-like effect in cafeteria diet-fed rats T. Utkan1 ° , T. Demirtas1 , E. Aksoz2 , S. Arkan3 1 Kocaeli University Medical Faculty, Pharmacology, Kocaeli, Turkey; 2 Balikesir University Medical Faculty, Pharmacology, Balikesir, Turkey; 3 Kocaeli University Medical Faculty, Physiology, Kocaeli, Turkey Purpose of the study: An increasing number of studies have revealed that obesity is associated with depression. Recent studies also have reported that obesity is not only as a metabolic disorder but also as an inflammatory disease. Moreover, it has been suggested that proinflammatory cytokines cause depressive symptoms and anti-TNF-a treatment ameliorated these symptoms of patients. We have previously demonstrated that TNF-a inhibition decreased depression-like behaviour in an animal model of depression [1]. The purpose of the present study was to investigate the effect of chronic etanercept, a TNF-a inhibitor, on depressive-like behavior in cafeteria diet (CD)-fed rats. Methods: Male weanling Wistar Albino rats (50−70 g, 30 days after birth) were divided into three groups (n = 10): First group of rats (control) was fed on standard pelleted diet. The second group of animals (obese) was fed on CD which is a high-fat diet in order to generate a diet-induced obesity model as reported previously [2]. This diet was composed by a mixture of pate, bacon, chips, cookies, chocolate and chow with proportions of 2:1:1:1:1:1, respectively, and was given to each rat daily. The last group (etanercept-treated) was also fed on CD and treated with etanercept (0.8 mg/kg/weekly/subcutaneously) during 12 weeks. The body weights of animals were measured weekly. Forced swimming test (FST), the sucrose consumption and preference test were used to investigate antidepressant effect of etanercept. Total locomotor activity (TLA) was also measured. Significant differences were determined using one-way ANOVA followed by Tukey’s post hoc tests. The level of significance was assumed to be p < 0.05. Results: After 12 weeks, the body weight of obese group was higher than control (p < 0.0001) and etanercept-treated group was lower than both control and obese group (p < 0.0001). There was no significant difference between three groups in terms of TLA (p > 0.05). In FST, there were differences between three groups in terms of immobility time during second day of testing
[1] Karson, A., Demirtas, T., Bayramg¨urler, D., Balci, F., Utkan, T., 2013. Chronic administration of infliximab (TNF-a inhibitor) decreases depression and anxiety-like behavior in rat model of chronic mild stress. Basic Clin Pharmacol Toxicol. 112(5), 335–340. [2] Garcia-Diaz, D.F., Campion, J., Milagro, F.I., Lomba, A., Marzo, F., Martinez, J.A., 2007. Chronic mild stress induces variations in locomotor behavior and metabolic rates in high fat fed rats. J Physiol Biochem. 63(4), 337–346.
P.1.g.052 Serotonin transporter-independent actions of the antidepressant vortioxetine as revealed in studies of the SERT Met172 mouse A. Nackenoff1 ° , L. Simmler1 , N. Baganz1 , K. Paffenroth1 , G. Stanwood1 , A. Pehrson2 , C. Sanchez2 , R. Blakely1 1 Vanderbilt University, Pharmacology, Nashville, USA; 2 Lundbeck Research USA, Pharmacology, Paramus, USA Purpose: Depression is one of the most common and burdensome disorders worldwide. The most widely prescribed antidepressants are serotonin (5-HT) selective reuptake inhibitors (SSRIs), believed to provide therapeutic benefit by inhibiting 5-HT reuptake by the 5-HT transporter (SERT) and thus elevating extracellular 5-HT levels. To improve efficacy, a number of drugs have been developed that offer additional target engagements, including other neurotransmitter transporters and receptors. The efficacy of such agents raises important questions as the degree to which one (e.g., SERT) or more of the anticipated targets accounts for therapeutic efficacy. Even for SSRIs, statements as to target requirements rely on data from the small fraction of assayable targets expressed by the mammalian genome. Methods: In the present report, we describe our efforts to investigate antidepressant targeting specificity using a novel transgenic mouse model in which the high-affinity interactions of many antidepressants at the SERT has been disabled without alteration of 5-HT transport function. In this effort, we seek to understand the degree to which vortioxetine, an approved antidepressant, requires SERT antagonism in acute tests with predictive validity for antidepressant efficacy given that the drug also has significant interactions with 5-HT1A, 5-HT1B, 5-HT1D, 5-HT3 and 5-HT7 receptors at clinically relevant doses. Results: Using the SERT M172 mouse model [1], we provide evidence that the acute, antidepressant actions of vortioxetine do not require SERT antagonism. In initial studies, using 5-HT uptake assays in human SERT M172 transfected cells and SERT M172
[2]
[3]
[4]
[5]
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paroxetine and fatty acid metabolism in recovery from major depressive disorder. Eur Neuropsychopharmacol 24, S56-S57. Ruh´e, H.G., Booij, J., Veltman, D.J., Michel, M.C., Schene, A.H., 2012. Successful pharmacologic treatment of major depressive disorder attenuates amygdala activation to negative facial expressions: a functional magnetic resonance imaging study. J Clin Psychiatry 73, 451−9. Mocking, R.J., Verburg, H.F., Westerink, A.M., Assies, J., Vaz, F.M., Koeter, M.W.J., Ruh´e, H.G., Schene, A.H. Fatty acid metabolism and its longitudinal relationship with the hypothalamic-pituitary-adrenal axis in major depression: associations with prospective antidepressant response. Psychoneuroendocrinology 59, 1−13. Assies, J., Mocking, R.J., Lok, A., Ruh´e, H.G., Pouwer, F., Schene, A.H., 2014. Effects of oxidative stress on fatty acid- and onecarbon-metabolism in psychiatric and cardiovascular disease comorbidity. Acta Psychiatr Scand 130, 163−80. Ruh´e, H.G., Khoenkhoen, S.J., Ottenhof, K.W., Koeter, M.W., Mocking, R.J., Schene, A.H., 2015. Longitudinal effects of the SSRI paroxetine on salivary cortisol in Major Depressive Disorder. Psychoneuroendocrinology 52, 261−71.
P.1.g.048 Blockade of CB1 cannabinoid receptors and activation of CB2 interact to prevent cocaine-responses P. Gobira1 ° , F. Moreira1 1 Federal University of Minas gerais, Pharmacology, Belo Horizonte, Brazil Introduction: Type-one (CB1-R) and type-two (CB2-R) cannabinoid receptors are responsible for the pharmacological effects of D-9-tetrahydrocannabinol, the main active compound from Cannabis sativa. Their endogenous ligands, termed endocannabinoids, act upon the brain dopaminergic mesocorticolimbic system, which is directly or indirectly targeted by most addictive drugs. The possible interactions between CB1-R and CB2-R, however, have remained to be investigated. Thus, this study was designed to test the hypothesis that CB1 blockade shifts endocannabinoid actions to CB2-R and inhibits cocaine-induced hyperlocomotion. Methods and Results: Male Swiss mice (n = 7−10/group) received systemic injections of compounds acting on CB1-R and CB2-R followed by cocaine (20 mg/kg). The total distance travelled was recorded in an arena and analyzed by ANOVA followed by Newman-Keuls test. A two-way repeated-measures ANOVA followed by Bonferroni post hoc was used to analyze the differences in Conditioneted Place Preference (CPP) scores among the test conditions. First, we tested whether the CB1-R blockade prevents cocaine-induced hyperlocomotion and found that the antagonist, rimonabant (1, 3 and 10 mg/kg), was effective at the higher dose. Then, we investigated if this compound would act by shifting endocannabinoid actions to CB2-R. In line with our hypothesis, the CB2-R antagonist, AM 630 (10 and 20 mg/kg), reversed the effects of rimonabant (10 mg/kg). Then we tested if our hypothesis also extended to effects of cocaine induced c-Fos expression in the nucleus accubens, core and shell. We found that Rimonabant (10 mg/kg) attenuated the increasing in cFos expression induced by cocaine, in both region. Furthermore, in line with behavioral results previously exposed, the pretreatment with AM 630 reverses this effect of Rimonabant. To further explore the role of CB2-R, we tested if its activation would mimic the effect of CB1-R blockade. Indeed, the higher dose of the selective agonist, JWH-133 (5, 10 and 20 mg/kg), prevented cocaine-induced hyperlocomotion. We also demonstrated that rimonabant and JWH-133 were also effective when combined at sub-threshold doses (3 and 10 mg/kg). To investigate which endocannabinoid would be involved in this effect,we tested the effect of inhibition of endocannabinoids hydrolysis in cocaine-induced
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hyperlocomotion. Hydrolysis inhibition of anandamide and 2-AG didn’t inhibited cocaine-action. However when combined with a subthreshold dose of rimonabant, hydrolysis inhibition of 2-AG attenuated cocaine-hyperlocomotion. None of the compounds induced changes in basal locomotion. Finally we test if this interaction between cannabinoid receptors in conditioned place preference (CPP) protocol. As expected Rimonabanto(10 mg/kg) innibited the acquisition of cocaine-induced CPP. Confirming our hypothesis the CB2-R antagonist reversed this rimonabanto-effect. Conclusion: Our results demonstrate that CB1-R blockade and CB2-R activation interact to prevent cocaine-induced hyperlocomotion. We also showed that 2-AG has a important role in this process. In conclusion we proposed that blockade of CB1 receptor redirects 2Ag action to CB2 receptor, and the activation of this last is responsible by prevent cocaine-response. This represents a possible mechanism through which the endocannabinoid system modulates the effects of this psychostimulant drug.
(F(2,27) = 12.09, p = 0.0002). Obese rats exhibited more immobility than control group (p < 0.001), while there was no difference between control and etanercept-treated group (p > 0.05). Sucrose consumption in obese group was significantly lower than the control group (p < 0.05). However, there was no significant difference between etanercept-treated and control group in terms of sucrose consumption (p > 0.05). In sucrose preference test, the obese group preferred sucrose less than control group (p < 0.0001) and the behavior of rats in etanercept-treated group did not differ significantly from the control group (p > 0.05). Conclusions: The results of present study indicated that chronic etanercept treatment decreased depressive-like behavior in CD-fed rats, indicating that TNF-a may play a crucial role in obesityrelated depression. The data strongly suggest that etanercept may be useful in clinical practice as an antidepressant drug moreover its co-administration with antidepressant drugs may potentiate their clinical efficacy in patients. References
P.1.g.049 Chronic etanercept treatment exerts antidepressant-like effect in cafeteria diet-fed rats T. Utkan1 ° , T. Demirtas1 , E. Aksoz2 , S. Arkan3 1 Kocaeli University Medical Faculty, Pharmacology, Kocaeli, Turkey; 2 Balikesir University Medical Faculty, Pharmacology, Balikesir, Turkey; 3 Kocaeli University Medical Faculty, Physiology, Kocaeli, Turkey Purpose of the study: An increasing number of studies have revealed that obesity is associated with depression. Recent studies also have reported that obesity is not only as a metabolic disorder but also as an inflammatory disease. Moreover, it has been suggested that proinflammatory cytokines cause depressive symptoms and anti-TNF-a treatment ameliorated these symptoms of patients. We have previously demonstrated that TNF-a inhibition decreased depression-like behaviour in an animal model of depression [1]. The purpose of the present study was to investigate the effect of chronic etanercept, a TNF-a inhibitor, on depressive-like behavior in cafeteria diet (CD)-fed rats. Methods: Male weanling Wistar Albino rats (50−70 g, 30 days after birth) were divided into three groups (n = 10): First group of rats (control) was fed on standard pelleted diet. The second group of animals (obese) was fed on CD which is a high-fat diet in order to generate a diet-induced obesity model as reported previously [2]. This diet was composed by a mixture of pate, bacon, chips, cookies, chocolate and chow with proportions of 2:1:1:1:1:1, respectively, and was given to each rat daily. The last group (etanercept-treated) was also fed on CD and treated with etanercept (0.8 mg/kg/weekly/subcutaneously) during 12 weeks. The body weights of animals were measured weekly. Forced swimming test (FST), the sucrose consumption and preference test were used to investigate antidepressant effect of etanercept. Total locomotor activity (TLA) was also measured. Significant differences were determined using one-way ANOVA followed by Tukey’s post hoc tests. The level of significance was assumed to be p < 0.05. Results: After 12 weeks, the body weight of obese group was higher than control (p < 0.0001) and etanercept-treated group was lower than both control and obese group (p < 0.0001). There was no significant difference between three groups in terms of TLA (p > 0.05). In FST, there were differences between three groups in terms of immobility time during second day of testing
[1] Karson, A., Demirtas, T., Bayramg¨urler, D., Balci, F., Utkan, T., 2013. Chronic administration of infliximab (TNF-a inhibitor) decreases depression and anxiety-like behavior in rat model of chronic mild stress. Basic Clin Pharmacol Toxicol. 112(5), 335–340. [2] Garcia-Diaz, D.F., Campion, J., Milagro, F.I., Lomba, A., Marzo, F., Martinez, J.A., 2007. Chronic mild stress induces variations in locomotor behavior and metabolic rates in high fat fed rats. J Physiol Biochem. 63(4), 337–346.
P.1.g.052 Serotonin transporter-independent actions of the antidepressant vortioxetine as revealed in studies of the SERT Met172 mouse A. Nackenoff1 ° , L. Simmler1 , N. Baganz1 , K. Paffenroth1 , G. Stanwood1 , A. Pehrson2 , C. Sanchez2 , R. Blakely1 1 Vanderbilt University, Pharmacology, Nashville, USA; 2 Lundbeck Research USA, Pharmacology, Paramus, USA Purpose: Depression is one of the most common and burdensome disorders worldwide. The most widely prescribed antidepressants are serotonin (5-HT) selective reuptake inhibitors (SSRIs), believed to provide therapeutic benefit by inhibiting 5-HT reuptake by the 5-HT transporter (SERT) and thus elevating extracellular 5-HT levels. To improve efficacy, a number of drugs have been developed that offer additional target engagements, including other neurotransmitter transporters and receptors. The efficacy of such agents raises important questions as the degree to which one (e.g., SERT) or more of the anticipated targets accounts for therapeutic efficacy. Even for SSRIs, statements as to target requirements rely on data from the small fraction of assayable targets expressed by the mammalian genome. Methods: In the present report, we describe our efforts to investigate antidepressant targeting specificity using a novel transgenic mouse model in which the high-affinity interactions of many antidepressants at the SERT has been disabled without alteration of 5-HT transport function. In this effort, we seek to understand the degree to which vortioxetine, an approved antidepressant, requires SERT antagonism in acute tests with predictive validity for antidepressant efficacy given that the drug also has significant interactions with 5-HT1A, 5-HT1B, 5-HT1D, 5-HT3 and 5-HT7 receptors at clinically relevant doses. Results: Using the SERT M172 mouse model [1], we provide evidence that the acute, antidepressant actions of vortioxetine do not require SERT antagonism. In initial studies, using 5-HT uptake assays in human SERT M172 transfected cells and SERT M172