Objective We aimed to investigate whether antagonism of the cannabinoid CB1 receptor(CB1R)could affect novel object recognition(NOR)memory in chronically rapid eye movement sleep-deprived(RSD)rats.Methods The animals ...Objective We aimed to investigate whether antagonism of the cannabinoid CB1 receptor(CB1R)could affect novel object recognition(NOR)memory in chronically rapid eye movement sleep-deprived(RSD)rats.Methods The animals were examined for recognition memory following a 7-day chronic partial RSD paradigm using the multiple platform technique.The CB1R antagonist rimonabant(1 or 3 mg/kg,i.p.)was administered either at one hour prior to the sample phase for acquisition,or immediately after the sample phase for consolidation,or at one hour before the test phase for retrieval of NOR memory.For the reconsolidation task,rimonabant was administered immediately after the second sample phase.Results The RSD episode impaired acquisition,consolidation,and retrieval,but it did not affect the reconsolidation of NOR memory.Rimonabant administration did not affect acquisition,consolidation,and reconsolidation;however,it attenuated impairment of the retrieval of NOR memory induced by chronic RSD.Conclusions These findings,along with our previous report,would seem to suggest that RSD may affect different phases of recognition memory based on its duration.Importantly,it seems that the CB1R may,at least in part,be involved in the adverse effects of chronic RSD on the retrieval,but not in the acquisition,consolidation,and reconsolidation,of NOR memory.展开更多
AIM To determine whether Nucb2/nesfatin1 production is regulated by the cannabinoid system through the intracellular m TOR pathway in the stomach.METHODS Sprague Dawley rats were treated with vehicle, rimonabant, rapa...AIM To determine whether Nucb2/nesfatin1 production is regulated by the cannabinoid system through the intracellular m TOR pathway in the stomach.METHODS Sprague Dawley rats were treated with vehicle, rimonabant, rapamycin or rapamycin+rimonabant. Gastric tissue obtained from the animals was used for biochemical assays: Nucb2 m RNA measurement by real time PCR, gastric Nucb2/nesfatin protein content by western blot, and gastric explants to obtain gastric secretomes. Nucb2/nesfatin levels were measured in gastric secretomes and plasma using enzyme-linked immunosorbent assay. RESULTS The inhibition of cannabinoid receptor 1(CB1) by the peripheral injection of an inverse agonist, namely rimonabant, decreases food intake and increases the gastric secretion and circulating levels of Nucb2/nesfatin-1. In addition, rimonabant treatment activates m TOR pathway in the stomach as showed by the increase in pm TOR/m TOR expression in gastric tissue obtained from rimonabant treated animals. These effects were confirmed by the use of a CB1 antagonist, AM281. When the intracellular pathway m TOR/S6 k was inactivated by chronic treatment with rapamycin, rimonabant treatment was no longer able to stimulate the gastric secretion of Nucb2/nesfatin-1.CONCLUSION The peripheral cannabinoid system regulates food intake through a mechanism that implies gastric production and release of Nucb2/Nesfatin-1, which is mediated by the m TOR/S6 k pathway.展开更多
A novel and efficient method was developed for the synthesis of diarylpyrazole derivatives as cannabinoid CB1 receptor antagonist via four step reactions. The key step was the synthesis of a diarylpyrazole skeleton, w...A novel and efficient method was developed for the synthesis of diarylpyrazole derivatives as cannabinoid CB1 receptor antagonist via four step reactions. The key step was the synthesis of a diarylpyrazole skeleton, which involved initial condensation of the sodium salt of compound 12 with diazonium compounds, and further cyclization by heating at reflux in acetic acid. Eight diarylpyrazole derivatives and nine new synthesized compounds were characterized by 1H NMR, IR, MS, and elemental analysis. The reaction conditions were mild and the overall yields of the target compounds ranged from 26% to 44%.展开更多
BACKGROUND Antagonists of cannabinoid type 1 receptor(CB1)have been shown to promote body weight loss and improve insulin sensitivity.Cannabinoids decrease adiponectin,and CB1 blocker increase adiponectin.However,the ...BACKGROUND Antagonists of cannabinoid type 1 receptor(CB1)have been shown to promote body weight loss and improve insulin sensitivity.Cannabinoids decrease adiponectin,and CB1 blocker increase adiponectin.However,the mediators of CB1 actions are not well defined.AIM To investigate whether the beneficial effects of CB1 inhibition are,at least in part,mediated by adiponectin.METHODS We compared metabolic and inflammatory phenotypes of wild-type(WT)mice,CB1-null(CB1^(-/-))and CB1/adiponectin double-knockout(DKO)mice.We assessed the insulin sensitivity using insulin tolerance test and glucose tolerance test,and inflammation using flow cytometry analysis of macrophages.RESULTS CB1^(-/-)mice exhibited significantly reduced body weight and fat mass when compared to WT mice.While no significance was found in total daily food intake and locomotor activity,CB1^(-/-)mice showed increased energy expenditure,enhanced thermogenesis in brown adipose tissue(BAT),and improved insulin sensitivity compared to WT mice.DKO showed no difference in body weight,adiposity,nor insulin sensitivity;only showed a modestly elevated thermogenesis in BAT compared to CB1^(-/-)mice.The metabolic phenotype of DKO is largely similar to CB1^(-/-)mice,suggesting that adiponectin is not a key mediator of the metabolic effects of CB1.Interestingly,CB1^(-/-)mice showed reduced pro-inflammatory macrophage polarization in both peritoneal macrophages and adipose tissue macrophages compared to WT mice;in contrast,DKO mice exhibited increased pro-inflammatory macrophage polarization in these macrophages compared to CB1^(-/-)mice,suggesting that adiponectin is an important mediator of the inflammatory effect of CB1.CONCLUSION Our findings reveal that CB1 functions through both adiponectin-dependent and adiponectin-independent mechanisms:CB1 regulates energy metabolism in an adiponectin-independent manner,and inflammation in an adiponectin-dependent manner.The differential effects of adiponectin on CB1-mediated metabolic and inflammatory functions should be taken into consideration in CB1 antagonist utilization.展开更多
Many researchers employed mammalian expression system to artificially express cannabinoid receptors, but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports....Many researchers employed mammalian expression system to artificially express cannabinoid receptors, but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports. In present study, we demonstrated cannabinoid receptor protein was not able to be properly expressed with routine mammalian expression system. This inefficient expression was rescued by endowing an exogenous signal peptide ahead of cannabinoid receptor peptide. In addition, the artificially synthesized cannabinoid receptor was found to aggregate under routine sample denaturing temperatures (i.e.,≥95°C), forming a large molecular weight band when analyzed by immuno-blotting. Only denaturing temperatures ≤75°C yielded a clear band at the predicted molecular weight. Collectively, we showed that efficient mammalian expression of cannabinoid receptors need a signal peptide sequence, and described the requirement for a low sample denaturing temperature in immuno-blot analysis. These findings provide very useful information for efficient mammalian expression and immuno-blotting of membrane receptors.展开更多
OBJECTIVE Cannabis can be rewarding or aversive.Cannabis reward is believed to be mediated by activation of cannabinoid CB1 receptors(CB1 Rs) on GABAergic neurons that disinhibit dopaminergic neurons in the ventral te...OBJECTIVE Cannabis can be rewarding or aversive.Cannabis reward is believed to be mediated by activation of cannabinoid CB1 receptors(CB1 Rs) on GABAergic neurons that disinhibit dopaminergic neurons in the ventral tegmental area(VTA).However,little is known about the mechanisms underlying cannabis aversion in rodents.Our study aimed at dig the mechanisms underlying cannabis aversion.METHODS We first created CB1-floxed mice and then generated conditional CB1-knockout mice(VgluT2-CB1-/-) in glutamatergic neurons that express vesicular glutamate transporter 2(VgluT2).We then used immunohistochemistry and RNAscope in situ hybridization assays to examine whether CB1 Rs are expressed in VTA GABAergic neurons and glutamatergic neurons.We also used Cre-dependent viral vector to express light-sensitive channelrhodopsin-2 into VTA glutamatergic neurons.Next,conditioned place preference and intracranial self-stimulation(ICSS) maintained by optical activation of VTA glutamatergic neurons were employed to evaluate the effects of Δ9-THC on brain reward function.RESULTS CB1 Rs are found not only on VTA GABAergic neurons,but also on VTA glutamatergic neurons that express vesicular glutamate transporter 2(VgluT2).Photoactivation of VTA glutamatergic neurons produced robust intracranial self-stimulation(ICSS) behavior,which was dose-dependently blocked by DA receptor antagonists,but enhanced by cocaine.In contrast,Δ9-tetrahydrocannabinol(Δ9-THC),the major psychoactive component of cannabis,produced dose-dependent conditioned place aversion and a reduction in the above optical ICSS in VgluT2-cre control mice,but not in VgluT2-CB1-/-mice.CONCLUSION Activation of CB1 Rs in VgluT2-expressing glutamate neurons produces aversive effects that might explain why cannabinoid is not rewarding in rodents and might also account for individual differences in the hedonic effects of cannabis in humans.展开更多
【目的】观察大麻素1型受体(CB1R)在C57B/L6小鼠神经元和胶质细胞的表达及其在实验性自身免疫性脑脊髓炎(EAE)小鼠中枢神经系统(CNS)和外周免疫器官的动态变化及其作用。【方法】取C57B/L6胎鼠的海马培养神经元及新生C57B/L6新生小鼠的...【目的】观察大麻素1型受体(CB1R)在C57B/L6小鼠神经元和胶质细胞的表达及其在实验性自身免疫性脑脊髓炎(EAE)小鼠中枢神经系统(CNS)和外周免疫器官的动态变化及其作用。【方法】取C57B/L6胎鼠的海马培养神经元及新生C57B/L6新生小鼠的皮层培养星形胶质细胞和小胶质细胞,观察CB1R蛋白的表达;观察正常对照、完全弗氏佐剂、EAE和特异性CB1R抑制剂(SR141716A,SR1)干预组小鼠的神经功能缺损症状和体质量变化;用real time PCR检测CB1R m RNA表达;Western blot和荧光免疫组织化学法检测CB1R蛋白表达;用ELISA法检测细胞因子IL-1β、IL-4、IL-10、IL-17、IL-6、TNF-α、IFN-γ浓度的变化。【结果】1C57B/L6小鼠神经元和小胶质细胞表达CB1R,星形胶质细胞不表达CB1R。2EAE小鼠神经元CB1R的表达显著低于CFA小鼠(P<0.01),小胶质细胞CB1R的表达显著高于CFA小鼠(P<0.01)。EAE小鼠脾脏中CB1R的表达与相同时点CFA小鼠无显著性差异(P>0.05)。3SR1干预促进EAE早发,上调EAE小鼠CNS和脾脏抗原特异性T细胞IL-17,TNF-α,IL-1β和IL-6的表达(P<0.05)。【结论】1神经元和小胶质细胞表达CB1R。2EAE小鼠脾脏中CB1R显著升高没有疾病特异性,可能与非特异性免疫激活有关。3中枢神经细胞上的CB1R可能兼有神经保护和免疫调节双重作用,参与EAE的发生和发展。展开更多
基金Supported by the Research Council of Kermanshah University of Medical Sciences,Kermanshah,Iran for financial support(grant no.:990812).
文摘Objective We aimed to investigate whether antagonism of the cannabinoid CB1 receptor(CB1R)could affect novel object recognition(NOR)memory in chronically rapid eye movement sleep-deprived(RSD)rats.Methods The animals were examined for recognition memory following a 7-day chronic partial RSD paradigm using the multiple platform technique.The CB1R antagonist rimonabant(1 or 3 mg/kg,i.p.)was administered either at one hour prior to the sample phase for acquisition,or immediately after the sample phase for consolidation,or at one hour before the test phase for retrieval of NOR memory.For the reconsolidation task,rimonabant was administered immediately after the second sample phase.Results The RSD episode impaired acquisition,consolidation,and retrieval,but it did not affect the reconsolidation of NOR memory.Rimonabant administration did not affect acquisition,consolidation,and reconsolidation;however,it attenuated impairment of the retrieval of NOR memory induced by chronic RSD.Conclusions These findings,along with our previous report,would seem to suggest that RSD may affect different phases of recognition memory based on its duration.Importantly,it seems that the CB1R may,at least in part,be involved in the adverse effects of chronic RSD on the retrieval,but not in the acquisition,consolidation,and reconsolidation,of NOR memory.
基金Supported by Instituto de Salud Carlos III,No.PI15/01272 cofounded by FEDERFondo de Investigaciones Sanitarias(LS:I3SNS-SERGAS/ISCIII)Centro de Investigacion Biomedica en Red Fisiopatología de la Obesidad y Nutrición(CIBERobn)is a iniciative of the Instituto de Salud Carlos III(ISCIII)of Spain which is supported by FEDER funds
文摘AIM To determine whether Nucb2/nesfatin1 production is regulated by the cannabinoid system through the intracellular m TOR pathway in the stomach.METHODS Sprague Dawley rats were treated with vehicle, rimonabant, rapamycin or rapamycin+rimonabant. Gastric tissue obtained from the animals was used for biochemical assays: Nucb2 m RNA measurement by real time PCR, gastric Nucb2/nesfatin protein content by western blot, and gastric explants to obtain gastric secretomes. Nucb2/nesfatin levels were measured in gastric secretomes and plasma using enzyme-linked immunosorbent assay. RESULTS The inhibition of cannabinoid receptor 1(CB1) by the peripheral injection of an inverse agonist, namely rimonabant, decreases food intake and increases the gastric secretion and circulating levels of Nucb2/nesfatin-1. In addition, rimonabant treatment activates m TOR pathway in the stomach as showed by the increase in pm TOR/m TOR expression in gastric tissue obtained from rimonabant treated animals. These effects were confirmed by the use of a CB1 antagonist, AM281. When the intracellular pathway m TOR/S6 k was inactivated by chronic treatment with rapamycin, rimonabant treatment was no longer able to stimulate the gastric secretion of Nucb2/nesfatin-1.CONCLUSION The peripheral cannabinoid system regulates food intake through a mechanism that implies gastric production and release of Nucb2/Nesfatin-1, which is mediated by the m TOR/S6 k pathway.
基金Supported by the Program for New Century Excellent Talents in University of China(NosNCET-08-0668, 1154-NCET-002)the Outstanding Youth Foundation of Heilongjiang Province, China(NoJC200706)
文摘A novel and efficient method was developed for the synthesis of diarylpyrazole derivatives as cannabinoid CB1 receptor antagonist via four step reactions. The key step was the synthesis of a diarylpyrazole skeleton, which involved initial condensation of the sodium salt of compound 12 with diazonium compounds, and further cyclization by heating at reflux in acetic acid. Eight diarylpyrazole derivatives and nine new synthesized compounds were characterized by 1H NMR, IR, MS, and elemental analysis. The reaction conditions were mild and the overall yields of the target compounds ranged from 26% to 44%.
基金Supported by the NIH,No.DK118334 and No.AG064869and the BrightFocus,No.A2019630S(to Sun Y).
文摘BACKGROUND Antagonists of cannabinoid type 1 receptor(CB1)have been shown to promote body weight loss and improve insulin sensitivity.Cannabinoids decrease adiponectin,and CB1 blocker increase adiponectin.However,the mediators of CB1 actions are not well defined.AIM To investigate whether the beneficial effects of CB1 inhibition are,at least in part,mediated by adiponectin.METHODS We compared metabolic and inflammatory phenotypes of wild-type(WT)mice,CB1-null(CB1^(-/-))and CB1/adiponectin double-knockout(DKO)mice.We assessed the insulin sensitivity using insulin tolerance test and glucose tolerance test,and inflammation using flow cytometry analysis of macrophages.RESULTS CB1^(-/-)mice exhibited significantly reduced body weight and fat mass when compared to WT mice.While no significance was found in total daily food intake and locomotor activity,CB1^(-/-)mice showed increased energy expenditure,enhanced thermogenesis in brown adipose tissue(BAT),and improved insulin sensitivity compared to WT mice.DKO showed no difference in body weight,adiposity,nor insulin sensitivity;only showed a modestly elevated thermogenesis in BAT compared to CB1^(-/-)mice.The metabolic phenotype of DKO is largely similar to CB1^(-/-)mice,suggesting that adiponectin is not a key mediator of the metabolic effects of CB1.Interestingly,CB1^(-/-)mice showed reduced pro-inflammatory macrophage polarization in both peritoneal macrophages and adipose tissue macrophages compared to WT mice;in contrast,DKO mice exhibited increased pro-inflammatory macrophage polarization in these macrophages compared to CB1^(-/-)mice,suggesting that adiponectin is an important mediator of the inflammatory effect of CB1.CONCLUSION Our findings reveal that CB1 functions through both adiponectin-dependent and adiponectin-independent mechanisms:CB1 regulates energy metabolism in an adiponectin-independent manner,and inflammation in an adiponectin-dependent manner.The differential effects of adiponectin on CB1-mediated metabolic and inflammatory functions should be taken into consideration in CB1 antagonist utilization.
基金supported by a grant from Army Medical Research Program of China(No.08G168)
文摘Many researchers employed mammalian expression system to artificially express cannabinoid receptors, but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports. In present study, we demonstrated cannabinoid receptor protein was not able to be properly expressed with routine mammalian expression system. This inefficient expression was rescued by endowing an exogenous signal peptide ahead of cannabinoid receptor peptide. In addition, the artificially synthesized cannabinoid receptor was found to aggregate under routine sample denaturing temperatures (i.e.,≥95°C), forming a large molecular weight band when analyzed by immuno-blotting. Only denaturing temperatures ≤75°C yielded a clear band at the predicted molecular weight. Collectively, we showed that efficient mammalian expression of cannabinoid receptors need a signal peptide sequence, and described the requirement for a low sample denaturing temperature in immuno-blot analysis. These findings provide very useful information for efficient mammalian expression and immuno-blotting of membrane receptors.
文摘OBJECTIVE Cannabis can be rewarding or aversive.Cannabis reward is believed to be mediated by activation of cannabinoid CB1 receptors(CB1 Rs) on GABAergic neurons that disinhibit dopaminergic neurons in the ventral tegmental area(VTA).However,little is known about the mechanisms underlying cannabis aversion in rodents.Our study aimed at dig the mechanisms underlying cannabis aversion.METHODS We first created CB1-floxed mice and then generated conditional CB1-knockout mice(VgluT2-CB1-/-) in glutamatergic neurons that express vesicular glutamate transporter 2(VgluT2).We then used immunohistochemistry and RNAscope in situ hybridization assays to examine whether CB1 Rs are expressed in VTA GABAergic neurons and glutamatergic neurons.We also used Cre-dependent viral vector to express light-sensitive channelrhodopsin-2 into VTA glutamatergic neurons.Next,conditioned place preference and intracranial self-stimulation(ICSS) maintained by optical activation of VTA glutamatergic neurons were employed to evaluate the effects of Δ9-THC on brain reward function.RESULTS CB1 Rs are found not only on VTA GABAergic neurons,but also on VTA glutamatergic neurons that express vesicular glutamate transporter 2(VgluT2).Photoactivation of VTA glutamatergic neurons produced robust intracranial self-stimulation(ICSS) behavior,which was dose-dependently blocked by DA receptor antagonists,but enhanced by cocaine.In contrast,Δ9-tetrahydrocannabinol(Δ9-THC),the major psychoactive component of cannabis,produced dose-dependent conditioned place aversion and a reduction in the above optical ICSS in VgluT2-cre control mice,but not in VgluT2-CB1-/-mice.CONCLUSION Activation of CB1 Rs in VgluT2-expressing glutamate neurons produces aversive effects that might explain why cannabinoid is not rewarding in rodents and might also account for individual differences in the hedonic effects of cannabis in humans.
文摘【目的】观察大麻素1型受体(CB1R)在C57B/L6小鼠神经元和胶质细胞的表达及其在实验性自身免疫性脑脊髓炎(EAE)小鼠中枢神经系统(CNS)和外周免疫器官的动态变化及其作用。【方法】取C57B/L6胎鼠的海马培养神经元及新生C57B/L6新生小鼠的皮层培养星形胶质细胞和小胶质细胞,观察CB1R蛋白的表达;观察正常对照、完全弗氏佐剂、EAE和特异性CB1R抑制剂(SR141716A,SR1)干预组小鼠的神经功能缺损症状和体质量变化;用real time PCR检测CB1R m RNA表达;Western blot和荧光免疫组织化学法检测CB1R蛋白表达;用ELISA法检测细胞因子IL-1β、IL-4、IL-10、IL-17、IL-6、TNF-α、IFN-γ浓度的变化。【结果】1C57B/L6小鼠神经元和小胶质细胞表达CB1R,星形胶质细胞不表达CB1R。2EAE小鼠神经元CB1R的表达显著低于CFA小鼠(P<0.01),小胶质细胞CB1R的表达显著高于CFA小鼠(P<0.01)。EAE小鼠脾脏中CB1R的表达与相同时点CFA小鼠无显著性差异(P>0.05)。3SR1干预促进EAE早发,上调EAE小鼠CNS和脾脏抗原特异性T细胞IL-17,TNF-α,IL-1β和IL-6的表达(P<0.05)。【结论】1神经元和小胶质细胞表达CB1R。2EAE小鼠脾脏中CB1R显著升高没有疾病特异性,可能与非特异性免疫激活有关。3中枢神经细胞上的CB1R可能兼有神经保护和免疫调节双重作用,参与EAE的发生和发展。
