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
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
This study investigated the modulatory effect of synthetic cannabinoids WIN55,212-2 on 5-HT3 receptor-activated currents (I5-HT3) in cultured rat trigeminal ganglion (TG) neurons using whole-cell patch clamp technique...This study investigated the modulatory effect of synthetic cannabinoids WIN55,212-2 on 5-HT3 receptor-activated currents (I5-HT3) in cultured rat trigeminal ganglion (TG) neurons using whole-cell patch clamp technique. The results showed that: (1) The majority of examined neurons (78.70%) were sensitive to 5-HT (3–300 μmol/L). 5-HT induced inward currents in a concentration-dependent manner and the currents were blocked by ICS 205-930 (1 μmol/L), a selective antagonist of the 5-HT3 receptor; (2) Pre-application of WIN55,212-2 (0.01–1 μmol/L) significantly inhibited I5-HT3 reversibly in concentration-dependent and voltage-independent manners. The concentra-tion-response curve of 5-HT3 receptor was shifted downward by WIN55,212-2 without any change of the threshold value. The EC50 values of two curves were very close (17.5±4.5) mmol/L vs. (15.2±4.5) mmol/L and WIN55,212-2 decreased the maximal amplitude of I5-HT3 by (48.65±4.15)%; (3) Neither AM281, a selective CB1 receptor antagonist, nor AM630, a selective CB2 receptor antagonist reversed the inhibition of I5-HT3 by WIN55,212-2; (4) When WIN55,212-2 was given from 15 to 120 s before 5-HT application, inhibitory effect was gradually increased and the maximal inhibition took place at 90 s, and the inhibition remained at the same level after 90 s. We are led to concluded that-WIN55,212-2 inhibited I5-HT3 significantly and neither CB1 receptor antagonist nor CB2 receptor antagonist could reverse the inhibition of I5-HT3 by WIN55,212-2. Moreover, WIN55,212-2 is not an open channel blocker (OCB) of 5-HT3 receptor. WIN55,212-2 significantly inhibited 5-HT-activated currents in a non-competitive manner. The inhibition of I5-HT3 by WIN55,212-2 is probably new one of peripheral analgesic mechanisms of WIN55,212-2, but the mechanism by which WIN55,212-2 inhibits I5-HT3 warrants further investigation.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
Objective:To investigate the antinociceptive effect of tingenone on inflammatory pain,as well as and the involvement of the cannabinoid receptors type 2(CB2)and spinal microglia in this process.Methods:Male Swiss mice...Objective:To investigate the antinociceptive effect of tingenone on inflammatory pain,as well as and the involvement of the cannabinoid receptors type 2(CB2)and spinal microglia in this process.Methods:Male Swiss mice were subjected to inflammatory pain induced by intraplantar injection of carrageenan.The nociceptive threshold was measured by von Frey filaments test.Tingenone was administered orally 60 min before carrageenan injection.To evaluate the involvement of CB2 receptor,endocannabinoids,and microglia,AM630(a CB2 receptor antagonist),MAFP(an inhibitor of an enzyme that hydrolyses endocannabinoids),and minocycline(a microglial inhibitor)were given intrathecally 20 min before tingenone administration.In addition,an immunofluorescence assay was used to evaluate CB2 receptor and CD11 B(a microglial marker)expression in the spinal cord dorsal horn.Results:Tingenone significantly reduced carrageenan-induced hyperalgesia,which was reversed by pretreatment with AM630.MAFP and minocycline potentiated and prolonged the tingenoneinduced antinociception.CD11 B expression was increased in the spinal cord dorsal horn of mice with inflammatory pain pretreated with tingenone,which was reduced by AM630,MAFP,and minocycline.Conclusions:CB2 receptors and endocannabinoids participate in the tingenone-induced antinociception which may involve the inhibition of microglia at spinal level.展开更多
Background: Cannabinoid receptor subtype 1 (CB1) has a relationship to the proliferation of various cells including malignant tumoral cells. We investigated and compared the expression of CB1 in benign and malignant h...Background: Cannabinoid receptor subtype 1 (CB1) has a relationship to the proliferation of various cells including malignant tumoral cells. We investigated and compared the expression of CB1 in benign and malignant human prostate tissues and in benign and malignant human prostate cell lines, as well as its function for the proliferation of human prostate cancer cells. Methods: Real-time quantitative PCR was performed to compare its expressions in human prostate tissues (normal, benign hyperplasia, and cancer) and prostate cell lines (3 normal and 3 malignant). For localization of CB1, immunofluorescent staining with rabbit anti-CB1 polyclonal antibodies and tetramethyl isothiocyanate (TRITC)-labeled swine anti-rabbit immunoglobulin (DAKO) were used under fluorescence microscope. To further analyze whether cell death was induced by anandamide (non-selective agonist for CB1/CB2) via a receptor dependent mechanism, the viability of DU145 cells, which is known as androgen-insensitive prostate cancer cell, was measured using MTT assay. Results: CB1mRNA was found to be expressed in the all 3 human prostate tissues, however, CB1 protein was expressed in BPH and low grade malignant PC tissues, but not in high grade malignant PC tissues. CB1 as for cell lines, the expression of CB1 was low in malignant cell lines except for DU145. Anandamide elicited cell death, which was significantly inhibited by AM251 (selective antagonist for CB1), indicating that cell death induced by anandamide in DU145 cells was mediated by CB1. Anandamide time-dependently elicits up-regulation of CB1 in DU145 cells. Conclusions: CB1 may be an inhibitory regulator of androgen-insensitive human prostate cancer epithelial cell growth.展开更多
The amygdala is an important hub for regulating emotions and is involved in the pathophysiology of many mental diseases,such as depression and anxiety.Meanwhile,the endocannabinoid system plays a crucial role in regul...The amygdala is an important hub for regulating emotions and is involved in the pathophysiology of many mental diseases,such as depression and anxiety.Meanwhile,the endocannabinoid system plays a crucial role in regulating emotions and mainly functions through the cannabinoid type-1 receptor(CB1R),which is strongly expressed in the amygdala of non-human primates(NHPs).However,it remains largely unknown how the CB1Rs in the amygdala of NHPs regulate mental diseases.Here,we investigated the role of CB1R by knocking down the cannabinoid receptor 1(CNR1)gene encoding CB1R in the amygdala of adult marmosets through regional delivery of AAV-SaCas9-gRNA.We found that CB1R knockdown in the amygdala induced anxiety-like behaviors,including disrupted night sleep,agitated psychomotor activity in new environments,and reduced social desire.Moreover,marmosets with CB1R-knockdown had up-regulated plasma cortisol levels.These results indicate that the knockdown of CB1Rs in the amygdala induces anxiety-like behaviors in marmosets,and this may be the mechanism underlying the regulation of anxiety by CB1Rs in the amygdala of NHPs.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,rapamy...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
The rostral agranular insular cortex(RAIC)has been associated with pain modulation.Although the endogenous cannabinoid system(eCB)has been shown to regulate chronic pain,the roles of eCBs in the RAIC remain elusive un...The rostral agranular insular cortex(RAIC)has been associated with pain modulation.Although the endogenous cannabinoid system(eCB)has been shown to regulate chronic pain,the roles of eCBs in the RAIC remain elusive under the neuropathic pain state.Neuropathic pain was induced in C57BL/6 mice by common peroneal nerve(CPN)ligation.The roles of the eCB were tested in the RAIC of ligated CPN C57BL/6J mice,glutamatergic,or GABAergic neuron cannabinoid receptor 1(CB1R)knockdown mice with the whole-cell patch-clamp and pain behavioral methods.The E/I ratio(amplitude ratio between mEPSCs and mIPSCs)was significantly increased in layer V pyramidal neurons of the RAIC in CPN-ligated mice.Depolarization-induced suppression of inhibition but not depolarization-induced suppression of excitation in RAIC layer V pyramidal neurons were significantly increased in CPN-ligated mice.The analgesic effect of ACEA(a CB1R agonist)was alleviated along with bilateral dorsolateral funiculus lesions,with the administration of AM251(a CB1R antagonist),and in CB1R knockdown mice in GABAergic neurons,but not glutamatergic neurons of the RAIC.Our results suggest that CB1R activation reinforces the function of the descending pain inhibitory pathway via reducing the inhibition of glutamatergic layer V neurons by GABAergic neurons in the RAIC to induce an analgesic effect in neuropathic pain.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
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
Background and Objective: It has been found that human periodontal ligament (hPDL) cells express cannabinoid receptor CB2. However, the functional importance of CB2 in hPDL cells exposed to bacterial endotoxins is not...Background and Objective: It has been found that human periodontal ligament (hPDL) cells express cannabinoid receptor CB2. However, the functional importance of CB2 in hPDL cells exposed to bacterial endotoxins is not known. Here we investigate if the inflammation promoter lipopolysaccharide (LPS) affects CB2 expression and if activation of CB2 regulates LPS-induced pro-inflammatory cytokine production and osteoclastogenic gene expression in hPDL cells. Methods: The hPDL cells were obtained from extracted teeth of periodontally healthy subjects. CB2 expression in hPDL cells exposed to LPS was deter- mined by quantitative real-time PCR analysis. Then, the cells were incubated with or without CB2-specific agonist HU-308 before further stimulation with LPS. In some experiments, the cells were pre-treated with CB2-specific antagonist SR144528. The production of pro-inflammatory cytokines interleukin-1 beta (IL- 1β), interleukin-6 (IL-6) and tumor necrosis factoralpha (TNF-α) was assessed by enzyme-linked immunosorbent assay (ELISA). The mRNA expression of osteoclastogenic genes osteoprotegerin (OPG) and receptor activator of NF-κB ligand (RANKL) was examined using quantitative real-time PCR analysis. Results: CB2 expression in hPDL cells was markedly enhanced by LPS. HU-308 significantly suppressed the production of IL-1β, IL-6 and TNF-α exposed to LPS, whereas SR144528 attenuated this effect. The OPG/RANKL ratio decreased when exposed to LPS, furthermore increased significantly with the addition of HU-308 and finally decreased markedly after pretreatment with SR144528. Conclusion: Our study demonstrated that activation of CB2 had anti-inflammatory and anti-resorptive effects on LPS-stimulated hPDL cells. These findings suggest that activation of CB2 might be an effective therapeutic strategy for the treatment of inflammation and alveolar bone resorption in periodontitis.展开更多
With the support by the National Natural Science Foundation of China,the research team led by Prof.Li XiaoMing(李晓明)at the Center for Neuroscience,NHC and CAMS Key Laboratory of Medical Neurobiology,Zhejiang Univers...With the support by the National Natural Science Foundation of China,the research team led by Prof.Li XiaoMing(李晓明)at the Center for Neuroscience,NHC and CAMS Key Laboratory of Medical Neurobiology,Zhejiang University School of Medicine,uncovered the new circuit and molecular mechanisms of depression,which was published in Nature Medicine(2019,25(2):337-349).展开更多
Background Endocannabinoids acting via cannabinoid receptor 1(CB1R)can elicit increased intestinal permeability(a condition also called‘leaky gut’).Alcohol binge can adversely affect digestive functions,including in...Background Endocannabinoids acting via cannabinoid receptor 1(CB1R)can elicit increased intestinal permeability(a condition also called‘leaky gut’).Alcohol binge can adversely affect digestive functions,including intestinal permeability;however,the underlying mechanisms remain incompletely understood.The current study aimed at examining whether CB1R is involved in alcohol binge-induced intestinal permeability.Methods We developed intestinal epithelial-specific CB1R knockout(CB1IEC−/−)mice and evaluated the in vivo contribution of gut CB1R in alcohol binge-induced intestinal permeability.Results Alcohol binge increased anandamide levels in the proximal small intestine in association with increased intestinal permeability.Radioligand binding and functional assays confirmed that the genetic deletion of intestinal epithelial CB1R did not alter the density or functionality of CB1R in the brain.Additionally,a peripheral CB1R antagonist,(S)-MRI-1891(INV-202/monlunabant),exhibited comparable binding affinity to CB1R in brain homogenates.An acute oral administration of(S)-MRI-1891(3 mg/kg)reduced alcohol binge-induced intestinal permeability in littermate control CB1f/f(CB1 floxed/floxed)mice but had no effect in CB1IEC−/−mice,underscoring the role of intestinal CB1R in this phenomenon.Mechanistically,we found that alcohol activated intestinal epithelial CB1R-ERK1/2 pathway with subsequent downregulation of tight junction proteins and reduction in villi length.In addition,targeting intestinal CB1R and downstream ERK1/2 was able to reverse this process,with subsequent upregulation of tight junction proteins and increased villi length,thus improving gut barrier function.Despite the effects on intestinal permeability,deletion of intestinal CB1R did not significantly affect metabolic parameters and liver disease.Conclusion Our findings suggest that alcohol promotes leaky gut via the activation of gut epithelial CB1R and demonstrate that inhibition of CB1R with peripheral-restricted selective CB1R antagonists can prevent alcohol binge-induced intestinal permeability.展开更多
Being a great threaten for human health, obesity has become a pandemic chronic disease. There have been several therapeutic treatments for this social health issue, including diet and exercise therapy, medication and ...Being a great threaten for human health, obesity has become a pandemic chronic disease. There have been several therapeutic treatments for this social health issue, including diet and exercise therapy, medication and surgery, among which the diet is still the most common way. However, none of these therapeutic measures available is ideal, making it necessary to find an effective medical treatment. The endocannabinoid system, which is well known for its contributions in certain mental processes such as relaxation, amelioration of pain and anxiety, and sedation initiation, has been recently reported to play an essential role in regulating appetite and metabolism to maintain energy balance, leading to the belief that endocannabinoid system is closely related to obesity. This new discovery deepens our understanding of obesity, and provides us with a new direction for clinical obesity treatment. Rimonabant is an antagonist for CB1, and has entered the market in some countries. However, although effective as an anti-obesity drug, rimonabant also causes obviously adverse side-effects, thus is being doubted and denied for medical usage.展开更多
Cannabinoids are a group of compounds acting pri-marily via CB1 and CB2 receptors.The expression of cannabinoid receptors in normal liver is low or absent.However,many reports have proven up-regulation of the expressi...Cannabinoids are a group of compounds acting pri-marily via CB1 and CB2 receptors.The expression of cannabinoid receptors in normal liver is low or absent.However,many reports have proven up-regulation of the expression of CB1 and CB2 receptors in hepatic myofibroblasts and vascular endothelial cells,as well as increased concentration of endocannabinoids in liver in the course of chronic progressive liver diseases.It has been shown that CB1 receptor signalling exerts profibrogenic and proinflammatory effects in liver tis-sue,primarily due to the stimulation of hepatic stellate cells,whereas the activation of CB2 receptors inhibits or even reverses liver fibrogenesis.Similarly,CB1 re-ceptor stimulation contributes to progression of liver steatosis.In end-stage liver disease,the endocannabi-noid system has been shown to contribute to hepatic encephalopathy and vascular effects,such as portal hypertension,splanchnic vasodilatation,relative pe-ripheral hypotension and probably cirrhotic cardiomy-opathy.So far,available evidence is based on cellular cultures or animal models.Clinical data on the effects of cannabinoids in chronic liver diseases are limited.However,recent studies have shown the contribution of cannabis smoking to the progression of liver fibrosis and steatosis.Moreover,controlling CB1 or CB2 signal-ling appears to be an attractive target in managing liver diseases.展开更多
Background Vascular hyporeactivity, which occurs in the terminal stage of hemorrhagic shock, is believed to be critical for treating hemorrhagic shock. The present study was designed to examine whether the CB1 cannabi...Background Vascular hyporeactivity, which occurs in the terminal stage of hemorrhagic shock, is believed to be critical for treating hemorrhagic shock. The present study was designed to examine whether the CB1 cannabinoid receptor （CB1 R） was involved in the development of vascular hyporeactivity in rats suffering from hemorrhagic shock. Methods Sixteen animals were randomly divided into two groups （n=8 in each group）： sham-operated （Sham） and hemorrhagic shock （HS） groups. Hemorrhagic shock was induced by bleeding. The mean arterial pressure （MAP） was reduced to and stabilized at （25±5） mmHg for 2 hours. The vascular reactivity was determined by the response of MAP to norepinephrine （NE）. In later experiments another twelve animals were used in which the changes of CB1R mRNA and protein in aorta and superior mesenteric artery （SMA） were analyzed by RT-PCR and Western blotting. In addition, we investigated the effects of a CB1R antagonist on the vascular hyporeactivity and survival rates in rats with hemorrhagic shock. Survival rates were analyzed by the Fisher＇s exact probability test. The MAP response was analyzed by one-way analysis of variance （ANOVA）. Results Vascular hyporeactivity developed in all animals suffering from hemorrhagic shock. The expression of CBIR mRNA and protein in aorta and 2-3 branches of the SMA were significantly increased in the HS group after the development of vascular hyporeactivity when compared to those in Sham group. When SR141716A or AM251 was administered, the MAP response to NE was （41.75±4.08） mmHg or （44.78±1.80） mmHg respectively, which was higher than that in saline groups with （4.31±0.36） mmHg （P 〈0.01）. We also showed an increased 4-hour survival rate in the SR141716A or AM251-treated group with 20% or 30%, but with a statistically significant difference present between the AM251-treated and saline groups （P 〈0.05）. Conclusions CBIR is involved in vascular hyporeactivity resulting from hemorrhagic shock in rats, and CB1R antagonist may be useful in treating patients with traumatic, hemorrhagic shock who need field-rescue or initial treatment.展开更多
OBJECTIVE Over 30% of all new psychoactive substances identified by the UN Office on Drugs and Crime in 2016 were synthetic cannabinoids.The recent emergence of MAM-2201 on the illicit market is troubling because this...OBJECTIVE Over 30% of all new psychoactive substances identified by the UN Office on Drugs and Crime in 2016 were synthetic cannabinoids.The recent emergence of MAM-2201 on the illicit market is troubling because this drug has no precedent in either the scientific or patent literature,and appears to be a novel compound developed specifically as a "graymarket" drug of abuse bystructurally combining the known synthetic cannabinoids JWH-122 and AM-2201.There is currently no published information regarding the pharmacology of MAM-2201.METHODS The present studies characterized cannabinoid-like effects of MAM-2201 in vitro(interactions with cannabinoid type 1 receptors[CB1 Rs]) and in vivo(in mice and rats).RESULTS In a radioligand binding assay using [3 H]CP55,940 in HEK cell membranes transfected with the CB1 R,MAM-2201(K i=5.4 nmol·L^(-1)),had higher binding affinity than WIN 55,212-2(K i=80 nmol·L^(-1)),and D9-THC(K i=8.3 nmol·L^(-1)).The E max values for MAM-2201 and WIN 55,212-2 in an assay of agonist inhibition of forskolin-stimulated c AMP were 85%(EC50=0.45 nmol·L^(-1)) and 95%,respectively,as compared with the D9-THC E max of 74%.In mice,MAM-2201(0.003-1.0 mg·kg^(-1),IP) produced dose-dependent cannabimimetic effects which were both more potent and more effective than those of D9-THC.MAM-2201 and D9-THC dose-dependently produced hypothermia:ED50=0.287 and 25.4 mg·kg^(-1),analgesia:ED50=0.125 and 29.4 mg·kg^(-1),and catalepsy:ED50=0.301 and18.9 mg·kg^(-1) in adult male CD1 mice.Importantly,MAM-2201 also elicited convulsant effects at a dose of 1.0 mg·kg^(-1) in 8/8 murine subjects.In rats,MAM-2201 produced dose-dependent D9-THC-like interoceptive effects in subjects trained to discriminate 3.0 mg·kg^(-1)(IP) D9-THC from saline.CONCLUSION MAM-2201 binds CB1 Rs with high affinity and agonist efficacy,and functions as a potent cannabinoid agonist in vivo across several complementary measures of cannabinoid activity in two rodent species.展开更多
Alcohol is a well-recognized teratogen that can causevariable physical and behavioral effects on the fetus.Alcohol use and abuse during pregnancy is one of the major health and societal problems and has been linked to...Alcohol is a well-recognized teratogen that can causevariable physical and behavioral effects on the fetus.Alcohol use and abuse during pregnancy is one of the major health and societal problems and has been linked to a wide range of birth defects in the offspring collectively termed as fetal alcohol spectrum disorder(FASD). The severity of abnormalities may depend on a number of factors that include the amount, the frequency, the period during gestation and the route of alcohol administration. The current knowledge about the neurobiological basis of FASD is limited. However, recent studies have suggested that the membrane-derived lipids especially bioactive endogenous cannabinoids(eCB)such as arachidonyl ethanolamide and 2-arachidonyl glycerol resulting from alcohol exposure, may play a significant role in modulating neurophysiological and neurobehavioral effects in chronic alcohol exposed adult animals. Based on these findings and on reported studies on the role of eCB signaling in neurodevelopment and behavior, it is speculated that the eC B signaling may play a critical role in fetal alcohol syndrome and FASD-related behavioral effects. The current discussion will touch upon some of the mechanistic explanations about the role of eCB signaling system in FASD and provide further guidance for future direction.展开更多
Cannabis has a detrimental impact on the developing nervous system. Therefore, regular consumption of cannabis by pregnant and lactating woman poses a potential risk to neuronal growth in fetuses and infants. Indeed, ...Cannabis has a detrimental impact on the developing nervous system. Therefore, regular consumption of cannabis by pregnant and lactating woman poses a potential risk to neuronal growth in fetuses and infants. Indeed, endogenous cannabis-like molecules called endocannabinoids regulate many physiological processes, including neurogenesis, axon guidance, and synaptic plasticity through CB1 receptors. To investigate the physiological role of CB1 receptors on peripheral sensory nerve growth, the endocannabinoid 2-arachidonoyl glycerol was added to cultured chick dorsal root ganglion neurons. This compound inhibited neurite elongation and induced growth cone collapse in a dose- and time-dependent manner. These data suggest that caution should be exercised regarding maternal cannabis use during pregnancy. Because ectopic sprouting and abnormal neuronal network connections are considered to be a cause of neuropathic pain, our current data imply an additional role of endocannabinoids as inhibitors of the formation of pain-maintenance networks.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 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.
基金supported by National Natural Science Foundation of China(No.30271500)Science and Tech-nology Research Project Fund from the Department of Edu-cation of Hubei Province of China(No.B20115101)
文摘This study investigated the modulatory effect of synthetic cannabinoids WIN55,212-2 on 5-HT3 receptor-activated currents (I5-HT3) in cultured rat trigeminal ganglion (TG) neurons using whole-cell patch clamp technique. The results showed that: (1) The majority of examined neurons (78.70%) were sensitive to 5-HT (3–300 μmol/L). 5-HT induced inward currents in a concentration-dependent manner and the currents were blocked by ICS 205-930 (1 μmol/L), a selective antagonist of the 5-HT3 receptor; (2) Pre-application of WIN55,212-2 (0.01–1 μmol/L) significantly inhibited I5-HT3 reversibly in concentration-dependent and voltage-independent manners. The concentra-tion-response curve of 5-HT3 receptor was shifted downward by WIN55,212-2 without any change of the threshold value. The EC50 values of two curves were very close (17.5±4.5) mmol/L vs. (15.2±4.5) mmol/L and WIN55,212-2 decreased the maximal amplitude of I5-HT3 by (48.65±4.15)%; (3) Neither AM281, a selective CB1 receptor antagonist, nor AM630, a selective CB2 receptor antagonist reversed the inhibition of I5-HT3 by WIN55,212-2; (4) When WIN55,212-2 was given from 15 to 120 s before 5-HT application, inhibitory effect was gradually increased and the maximal inhibition took place at 90 s, and the inhibition remained at the same level after 90 s. We are led to concluded that-WIN55,212-2 inhibited I5-HT3 significantly and neither CB1 receptor antagonist nor CB2 receptor antagonist could reverse the inhibition of I5-HT3 by WIN55,212-2. Moreover, WIN55,212-2 is not an open channel blocker (OCB) of 5-HT3 receptor. WIN55,212-2 significantly inhibited 5-HT-activated currents in a non-competitive manner. The inhibition of I5-HT3 by WIN55,212-2 is probably new one of peripheral analgesic mechanisms of WIN55,212-2, but the mechanism by which WIN55,212-2 inhibits I5-HT3 warrants further investigation.
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 Coordenacao de Aperfeicoamento de Pessoal de Nível Superior-Brasil(CAPES)(Finance Code 001)
文摘Objective:To investigate the antinociceptive effect of tingenone on inflammatory pain,as well as and the involvement of the cannabinoid receptors type 2(CB2)and spinal microglia in this process.Methods:Male Swiss mice were subjected to inflammatory pain induced by intraplantar injection of carrageenan.The nociceptive threshold was measured by von Frey filaments test.Tingenone was administered orally 60 min before carrageenan injection.To evaluate the involvement of CB2 receptor,endocannabinoids,and microglia,AM630(a CB2 receptor antagonist),MAFP(an inhibitor of an enzyme that hydrolyses endocannabinoids),and minocycline(a microglial inhibitor)were given intrathecally 20 min before tingenone administration.In addition,an immunofluorescence assay was used to evaluate CB2 receptor and CD11 B(a microglial marker)expression in the spinal cord dorsal horn.Results:Tingenone significantly reduced carrageenan-induced hyperalgesia,which was reversed by pretreatment with AM630.MAFP and minocycline potentiated and prolonged the tingenoneinduced antinociception.CD11 B expression was increased in the spinal cord dorsal horn of mice with inflammatory pain pretreated with tingenone,which was reduced by AM630,MAFP,and minocycline.Conclusions:CB2 receptors and endocannabinoids participate in the tingenone-induced antinociception which may involve the inhibition of microglia at spinal level.
文摘Background: Cannabinoid receptor subtype 1 (CB1) has a relationship to the proliferation of various cells including malignant tumoral cells. We investigated and compared the expression of CB1 in benign and malignant human prostate tissues and in benign and malignant human prostate cell lines, as well as its function for the proliferation of human prostate cancer cells. Methods: Real-time quantitative PCR was performed to compare its expressions in human prostate tissues (normal, benign hyperplasia, and cancer) and prostate cell lines (3 normal and 3 malignant). For localization of CB1, immunofluorescent staining with rabbit anti-CB1 polyclonal antibodies and tetramethyl isothiocyanate (TRITC)-labeled swine anti-rabbit immunoglobulin (DAKO) were used under fluorescence microscope. To further analyze whether cell death was induced by anandamide (non-selective agonist for CB1/CB2) via a receptor dependent mechanism, the viability of DU145 cells, which is known as androgen-insensitive prostate cancer cell, was measured using MTT assay. Results: CB1mRNA was found to be expressed in the all 3 human prostate tissues, however, CB1 protein was expressed in BPH and low grade malignant PC tissues, but not in high grade malignant PC tissues. CB1 as for cell lines, the expression of CB1 was low in malignant cell lines except for DU145. Anandamide elicited cell death, which was significantly inhibited by AM251 (selective antagonist for CB1), indicating that cell death induced by anandamide in DU145 cells was mediated by CB1. Anandamide time-dependently elicits up-regulation of CB1 in DU145 cells. Conclusions: CB1 may be an inhibitory regulator of androgen-insensitive human prostate cancer epithelial cell growth.
基金supported by the Zhejiang Province Natural Science Foundation of China(LD22H090003)Key-Area Research and Development Program of Guangdong Province(2019B030335001 and 2018B030334001)+3 种基金the National Natural Science Foundation of China(31871070,82090031,32071097,31871056,and 32170991)the Key R&D Program of Zhejiang Province(2020C03009)Fundamental Research Funds for the Central Universities(2021FZZX001-37)the CAMS Innovation Fund for Medical Sciences(2019-I2M-5-057).
文摘The amygdala is an important hub for regulating emotions and is involved in the pathophysiology of many mental diseases,such as depression and anxiety.Meanwhile,the endocannabinoid system plays a crucial role in regulating emotions and mainly functions through the cannabinoid type-1 receptor(CB1R),which is strongly expressed in the amygdala of non-human primates(NHPs).However,it remains largely unknown how the CB1Rs in the amygdala of NHPs regulate mental diseases.Here,we investigated the role of CB1R by knocking down the cannabinoid receptor 1(CNR1)gene encoding CB1R in the amygdala of adult marmosets through regional delivery of AAV-SaCas9-gRNA.We found that CB1R knockdown in the amygdala induced anxiety-like behaviors,including disrupted night sleep,agitated psychomotor activity in new environments,and reduced social desire.Moreover,marmosets with CB1R-knockdown had up-regulated plasma cortisol levels.These results indicate that the knockdown of CB1Rs in the amygdala induces anxiety-like behaviors in marmosets,and this may be the mechanism underlying the regulation of anxiety by CB1Rs in the amygdala of NHPs.
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This work was supported by the National Natural Science Foundation of China(32271056,81671081,and 81701095)University Science and Technology Fund Planning Projects(2022XC002 and 2019XB006).
文摘The rostral agranular insular cortex(RAIC)has been associated with pain modulation.Although the endogenous cannabinoid system(eCB)has been shown to regulate chronic pain,the roles of eCBs in the RAIC remain elusive under the neuropathic pain state.Neuropathic pain was induced in C57BL/6 mice by common peroneal nerve(CPN)ligation.The roles of the eCB were tested in the RAIC of ligated CPN C57BL/6J mice,glutamatergic,or GABAergic neuron cannabinoid receptor 1(CB1R)knockdown mice with the whole-cell patch-clamp and pain behavioral methods.The E/I ratio(amplitude ratio between mEPSCs and mIPSCs)was significantly increased in layer V pyramidal neurons of the RAIC in CPN-ligated mice.Depolarization-induced suppression of inhibition but not depolarization-induced suppression of excitation in RAIC layer V pyramidal neurons were significantly increased in CPN-ligated mice.The analgesic effect of ACEA(a CB1R agonist)was alleviated along with bilateral dorsolateral funiculus lesions,with the administration of AM251(a CB1R antagonist),and in CB1R knockdown mice in GABAergic neurons,but not glutamatergic neurons of the RAIC.Our results suggest that CB1R activation reinforces the function of the descending pain inhibitory pathway via reducing the inhibition of glutamatergic layer V neurons by GABAergic neurons in the RAIC to induce an analgesic effect in neuropathic pain.
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.
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.
文摘Background and Objective: It has been found that human periodontal ligament (hPDL) cells express cannabinoid receptor CB2. However, the functional importance of CB2 in hPDL cells exposed to bacterial endotoxins is not known. Here we investigate if the inflammation promoter lipopolysaccharide (LPS) affects CB2 expression and if activation of CB2 regulates LPS-induced pro-inflammatory cytokine production and osteoclastogenic gene expression in hPDL cells. Methods: The hPDL cells were obtained from extracted teeth of periodontally healthy subjects. CB2 expression in hPDL cells exposed to LPS was deter- mined by quantitative real-time PCR analysis. Then, the cells were incubated with or without CB2-specific agonist HU-308 before further stimulation with LPS. In some experiments, the cells were pre-treated with CB2-specific antagonist SR144528. The production of pro-inflammatory cytokines interleukin-1 beta (IL- 1β), interleukin-6 (IL-6) and tumor necrosis factoralpha (TNF-α) was assessed by enzyme-linked immunosorbent assay (ELISA). The mRNA expression of osteoclastogenic genes osteoprotegerin (OPG) and receptor activator of NF-κB ligand (RANKL) was examined using quantitative real-time PCR analysis. Results: CB2 expression in hPDL cells was markedly enhanced by LPS. HU-308 significantly suppressed the production of IL-1β, IL-6 and TNF-α exposed to LPS, whereas SR144528 attenuated this effect. The OPG/RANKL ratio decreased when exposed to LPS, furthermore increased significantly with the addition of HU-308 and finally decreased markedly after pretreatment with SR144528. Conclusion: Our study demonstrated that activation of CB2 had anti-inflammatory and anti-resorptive effects on LPS-stimulated hPDL cells. These findings suggest that activation of CB2 might be an effective therapeutic strategy for the treatment of inflammation and alveolar bone resorption in periodontitis.
文摘With the support by the National Natural Science Foundation of China,the research team led by Prof.Li XiaoMing(李晓明)at the Center for Neuroscience,NHC and CAMS Key Laboratory of Medical Neurobiology,Zhejiang University School of Medicine,uncovered the new circuit and molecular mechanisms of depression,which was published in Nature Medicine(2019,25(2):337-349).
基金supported by the intramural programme of NIAAA,NIH(AA00350 to GK,AA000369 and AA000368 to BG)supported by Grant PD-139012 of the National Research,Development and Innovation Office and the János Bolyai Research Scholarship of the Hungarian Academy of Sciences.
文摘Background Endocannabinoids acting via cannabinoid receptor 1(CB1R)can elicit increased intestinal permeability(a condition also called‘leaky gut’).Alcohol binge can adversely affect digestive functions,including intestinal permeability;however,the underlying mechanisms remain incompletely understood.The current study aimed at examining whether CB1R is involved in alcohol binge-induced intestinal permeability.Methods We developed intestinal epithelial-specific CB1R knockout(CB1IEC−/−)mice and evaluated the in vivo contribution of gut CB1R in alcohol binge-induced intestinal permeability.Results Alcohol binge increased anandamide levels in the proximal small intestine in association with increased intestinal permeability.Radioligand binding and functional assays confirmed that the genetic deletion of intestinal epithelial CB1R did not alter the density or functionality of CB1R in the brain.Additionally,a peripheral CB1R antagonist,(S)-MRI-1891(INV-202/monlunabant),exhibited comparable binding affinity to CB1R in brain homogenates.An acute oral administration of(S)-MRI-1891(3 mg/kg)reduced alcohol binge-induced intestinal permeability in littermate control CB1f/f(CB1 floxed/floxed)mice but had no effect in CB1IEC−/−mice,underscoring the role of intestinal CB1R in this phenomenon.Mechanistically,we found that alcohol activated intestinal epithelial CB1R-ERK1/2 pathway with subsequent downregulation of tight junction proteins and reduction in villi length.In addition,targeting intestinal CB1R and downstream ERK1/2 was able to reverse this process,with subsequent upregulation of tight junction proteins and increased villi length,thus improving gut barrier function.Despite the effects on intestinal permeability,deletion of intestinal CB1R did not significantly affect metabolic parameters and liver disease.Conclusion Our findings suggest that alcohol promotes leaky gut via the activation of gut epithelial CB1R and demonstrate that inhibition of CB1R with peripheral-restricted selective CB1R antagonists can prevent alcohol binge-induced intestinal permeability.
基金supported by the Study Grant (2007) for Medical Students of Second Military Medical University,China
文摘Being a great threaten for human health, obesity has become a pandemic chronic disease. There have been several therapeutic treatments for this social health issue, including diet and exercise therapy, medication and surgery, among which the diet is still the most common way. However, none of these therapeutic measures available is ideal, making it necessary to find an effective medical treatment. The endocannabinoid system, which is well known for its contributions in certain mental processes such as relaxation, amelioration of pain and anxiety, and sedation initiation, has been recently reported to play an essential role in regulating appetite and metabolism to maintain energy balance, leading to the belief that endocannabinoid system is closely related to obesity. This new discovery deepens our understanding of obesity, and provides us with a new direction for clinical obesity treatment. Rimonabant is an antagonist for CB1, and has entered the market in some countries. However, although effective as an anti-obesity drug, rimonabant also causes obviously adverse side-effects, thus is being doubted and denied for medical usage.
文摘Cannabinoids are a group of compounds acting pri-marily via CB1 and CB2 receptors.The expression of cannabinoid receptors in normal liver is low or absent.However,many reports have proven up-regulation of the expression of CB1 and CB2 receptors in hepatic myofibroblasts and vascular endothelial cells,as well as increased concentration of endocannabinoids in liver in the course of chronic progressive liver diseases.It has been shown that CB1 receptor signalling exerts profibrogenic and proinflammatory effects in liver tis-sue,primarily due to the stimulation of hepatic stellate cells,whereas the activation of CB2 receptors inhibits or even reverses liver fibrogenesis.Similarly,CB1 re-ceptor stimulation contributes to progression of liver steatosis.In end-stage liver disease,the endocannabi-noid system has been shown to contribute to hepatic encephalopathy and vascular effects,such as portal hypertension,splanchnic vasodilatation,relative pe-ripheral hypotension and probably cirrhotic cardiomy-opathy.So far,available evidence is based on cellular cultures or animal models.Clinical data on the effects of cannabinoids in chronic liver diseases are limited.However,recent studies have shown the contribution of cannabis smoking to the progression of liver fibrosis and steatosis.Moreover,controlling CB1 or CB2 signal-ling appears to be an attractive target in managing liver diseases.
基金This work was supported by the grants from the National Natural Science Foundation of China （No. 30471675, No. 30672041 and No. 30725039）, National Natural Science Foundation of Shaanxi Province （No. 2004K17-G15） and National Natural Science Foundation of PLA （No. 06G086）.
文摘Background Vascular hyporeactivity, which occurs in the terminal stage of hemorrhagic shock, is believed to be critical for treating hemorrhagic shock. The present study was designed to examine whether the CB1 cannabinoid receptor （CB1 R） was involved in the development of vascular hyporeactivity in rats suffering from hemorrhagic shock. Methods Sixteen animals were randomly divided into two groups （n=8 in each group）： sham-operated （Sham） and hemorrhagic shock （HS） groups. Hemorrhagic shock was induced by bleeding. The mean arterial pressure （MAP） was reduced to and stabilized at （25±5） mmHg for 2 hours. The vascular reactivity was determined by the response of MAP to norepinephrine （NE）. In later experiments another twelve animals were used in which the changes of CB1R mRNA and protein in aorta and superior mesenteric artery （SMA） were analyzed by RT-PCR and Western blotting. In addition, we investigated the effects of a CB1R antagonist on the vascular hyporeactivity and survival rates in rats with hemorrhagic shock. Survival rates were analyzed by the Fisher＇s exact probability test. The MAP response was analyzed by one-way analysis of variance （ANOVA）. Results Vascular hyporeactivity developed in all animals suffering from hemorrhagic shock. The expression of CBIR mRNA and protein in aorta and 2-3 branches of the SMA were significantly increased in the HS group after the development of vascular hyporeactivity when compared to those in Sham group. When SR141716A or AM251 was administered, the MAP response to NE was （41.75±4.08） mmHg or （44.78±1.80） mmHg respectively, which was higher than that in saline groups with （4.31±0.36） mmHg （P 〈0.01）. We also showed an increased 4-hour survival rate in the SR141716A or AM251-treated group with 20% or 30%, but with a statistically significant difference present between the AM251-treated and saline groups （P 〈0.05）. Conclusions CBIR is involved in vascular hyporeactivity resulting from hemorrhagic shock in rats, and CB1R antagonist may be useful in treating patients with traumatic, hemorrhagic shock who need field-rescue or initial treatment.
基金supported by Drug Enforcement Administration,National Center for Toxicological Research(protocol#E0763601)University of Arkansas for Medical Sciences
文摘OBJECTIVE Over 30% of all new psychoactive substances identified by the UN Office on Drugs and Crime in 2016 were synthetic cannabinoids.The recent emergence of MAM-2201 on the illicit market is troubling because this drug has no precedent in either the scientific or patent literature,and appears to be a novel compound developed specifically as a "graymarket" drug of abuse bystructurally combining the known synthetic cannabinoids JWH-122 and AM-2201.There is currently no published information regarding the pharmacology of MAM-2201.METHODS The present studies characterized cannabinoid-like effects of MAM-2201 in vitro(interactions with cannabinoid type 1 receptors[CB1 Rs]) and in vivo(in mice and rats).RESULTS In a radioligand binding assay using [3 H]CP55,940 in HEK cell membranes transfected with the CB1 R,MAM-2201(K i=5.4 nmol·L^(-1)),had higher binding affinity than WIN 55,212-2(K i=80 nmol·L^(-1)),and D9-THC(K i=8.3 nmol·L^(-1)).The E max values for MAM-2201 and WIN 55,212-2 in an assay of agonist inhibition of forskolin-stimulated c AMP were 85%(EC50=0.45 nmol·L^(-1)) and 95%,respectively,as compared with the D9-THC E max of 74%.In mice,MAM-2201(0.003-1.0 mg·kg^(-1),IP) produced dose-dependent cannabimimetic effects which were both more potent and more effective than those of D9-THC.MAM-2201 and D9-THC dose-dependently produced hypothermia:ED50=0.287 and 25.4 mg·kg^(-1),analgesia:ED50=0.125 and 29.4 mg·kg^(-1),and catalepsy:ED50=0.301 and18.9 mg·kg^(-1) in adult male CD1 mice.Importantly,MAM-2201 also elicited convulsant effects at a dose of 1.0 mg·kg^(-1) in 8/8 murine subjects.In rats,MAM-2201 produced dose-dependent D9-THC-like interoceptive effects in subjects trained to discriminate 3.0 mg·kg^(-1)(IP) D9-THC from saline.CONCLUSION MAM-2201 binds CB1 Rs with high affinity and agonist efficacy,and functions as a potent cannabinoid agonist in vivo across several complementary measures of cannabinoid activity in two rodent species.
文摘Alcohol is a well-recognized teratogen that can causevariable physical and behavioral effects on the fetus.Alcohol use and abuse during pregnancy is one of the major health and societal problems and has been linked to a wide range of birth defects in the offspring collectively termed as fetal alcohol spectrum disorder(FASD). The severity of abnormalities may depend on a number of factors that include the amount, the frequency, the period during gestation and the route of alcohol administration. The current knowledge about the neurobiological basis of FASD is limited. However, recent studies have suggested that the membrane-derived lipids especially bioactive endogenous cannabinoids(eCB)such as arachidonyl ethanolamide and 2-arachidonyl glycerol resulting from alcohol exposure, may play a significant role in modulating neurophysiological and neurobehavioral effects in chronic alcohol exposed adult animals. Based on these findings and on reported studies on the role of eCB signaling in neurodevelopment and behavior, it is speculated that the eC B signaling may play a critical role in fetal alcohol syndrome and FASD-related behavioral effects. The current discussion will touch upon some of the mechanistic explanations about the role of eCB signaling system in FASD and provide further guidance for future direction.
文摘Cannabis has a detrimental impact on the developing nervous system. Therefore, regular consumption of cannabis by pregnant and lactating woman poses a potential risk to neuronal growth in fetuses and infants. Indeed, endogenous cannabis-like molecules called endocannabinoids regulate many physiological processes, including neurogenesis, axon guidance, and synaptic plasticity through CB1 receptors. To investigate the physiological role of CB1 receptors on peripheral sensory nerve growth, the endocannabinoid 2-arachidonoyl glycerol was added to cultured chick dorsal root ganglion neurons. This compound inhibited neurite elongation and induced growth cone collapse in a dose- and time-dependent manner. These data suggest that caution should be exercised regarding maternal cannabis use during pregnancy. Because ectopic sprouting and abnormal neuronal network connections are considered to be a cause of neuropathic pain, our current data imply an additional role of endocannabinoids as inhibitors of the formation of pain-maintenance networks.
