Abused drug-induced intracranial self-stimulation is correlated with the alteration of dopamine transporter availability in the medial prefrontal cortex and nucleus accumbens of mice.

Intracranial self-stimulation (ICSS) of the medial forebrain bundle in mice is an experimental model use to assess the relative potential of reward-seeking behaviors. Here, we used the ICSS model to evaluate the abuse potential of 18 abused drugs: 3-Fluoroethamphetamine (3-FEA); methylphenidate; cocaine; dextroamphetamine; alpha-Pyrrolidinobutyrophenone (α-PBT); 4'-Fluoro-4-methylaminorex (4-FPO); methamphetamine; larocaine; phentermine; paramethoxymethamphetamine (PMMA); phendimetrazine; N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (AKB-48); Naphthalen-1-yl-(4-pentyloxynaphthalen-1-yl)methanone (CB-13); 4-Ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-210); Naphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-018); N-(ortho-methoxybenzyl)-4-ethylamphetamine (4-EA-NBOMe); N-[(2-Methoxyphenyl)methyl]-N-methyl-1-(4-methylphenyl)propan-2-amine (4-MMA-NBOMe); and 1-[1-(4-methoxyphenyl)cyclohexyl]piperidine (4-MeO-PCP). We determined dopamine transporter (DAT) availability in the medial prefrontal cortex (mPFC), striatum, and nucleus accumbens (NAc) after drug treatment. DAT availability in the mPFC and NAc significantly correlated with the ICSS threshold after drug treatment. Extracellular dopamine and calcium levels in PC-12 cells were measured following drug treatment. After drug treatment, Spearman rank and Pearson correlation analyses showed a significant difference between the extracellular dopamine level and the ICSS threshold. After drug treatment, Spearman rank correlation analysis showed a significant correlation between Ca2+ signaling and the ICSS threshold. A positive correlation exists between the ICSS threshold and DAT availability in the mPFC and NAc provoked by abused drugs. The relative potential of drug-induced reward-seeking behavior may be related to DAT availability-mediated extracellular dopamine levels in the mPFC and NAc.

Prenatal ketamine exposure impairs prepulse inhibition via arginine vasopressin receptor 1A-mediated GABAergic neuronal dysfunction in the striatum.

Ketamine is a widely used anesthetic with N-methyl-D-aspartate (NMDA) receptor antagonism. Exposure to ketamine and NMDA receptor antagonists may induce psychosis. However, the mechanism underlying the effects of ketamine on the immature brain remains unclear. In this study, NMDA receptor antagonists, ketamine and methoxetamine, were administered to pregnant F344 rats (E17). These regimens induce psychosis-like behaviors in the offspring, such as hyperlocomotion induced by MK-801, a non-competitive NMDA receptor antagonist. We also observed that prepulse inhibition (PPI) was significantly reduced. Interestingly, ketamine administration increased the arginine vasopressin receptor 1A (Avpr1a) expression levels in the striatum of offspring with abnormal behaviors. Methoxetamine, another NMDA receptor antagonist, also showed similar results. In addition, we demonstrated a viral vector-induced Avpr1a overexpression in the striatum-inhibited PPI. In the striatum of offspring, ketamine or methoxetamine treatment increased glutamate decarboxylase 67 (GAD67) and δ-aminobutyric acid (GABA) levels. These results show that prenatal NMDA receptor antagonist treatment induces GABAergic neuronal dysfunction and abnormalities in sensorimotor gating via regulating Avpr1a expression in the striatum.

Derivatives of 3, 4, 5-Trimethoxycinnamic Acid Ameliorate Stress-Induced Anxiety in Mice and Rats.

Stress is an overwhelming problem associated with neuronal damage leading to anxiety and depression. The compound 3, 4, 5-trimethoxycinnamic acid (TMCA) has shown anti-stress effects; however, its derivatives remained unknown for their anxiolytic properties. Here, therefore, we investigated derivatives of TMCA (dTMCA) for their anxiolytic effects using immobilization and electric shock-induced stress in rats. Derivatives of TMCA ameliorated anxiety in mice and rats revealed by extended period of time spent in the open arms of elevated plus maze. Stress-mediated repression of tyrosine hydroxylase (TH) protein expression in the amygdala regions of rat brain and dopamine levels in the PC12 cells was restored by two selected derivatives (TMCA#5 and TMCA#9). Unlike TH expression, stress-induced protein expression of phospho-extracellular signal-regulated kinase (pERK) was unaffected by both derivatives in rats. Given the preferential inhibitory activity of dTMCA on dopamine and serotonin receptors, serotonergic road map of cellular signaling could be their target for anxiolytic effects. Thus, dTMCA would be promising agents to prevent neuronal damage associated with rampant stressful conditions.

The designer benzodiazepine, flubromazepam, induces reward-enhancing and cardiotoxic effects in rodents.

The use of many benzodiazepines is controlled worldwide due to their high likelihood of abuse and potential adverse effects. Flubromazepam-a designer benzodiazepine-is a long-acting gamma-aminobutyric acid subtype A receptor agonist. There is currently a lack of scientific evidence regarding the potential for flubromazepam dependence or other adverse effects. This study aimed to evaluate the dependence potential, and cardiotoxicity via confirmation of the QT and RR intervals which are the factors on the electrical properties of the heart of flubromazepam in rodents. Using a conditioned place preference test, we discovered that mice treated intraperitoneally with flubromazepam (0.1 mg/kg) exhibited a significant preference for the flubromazepam-paired compartment, suggesting a potential for flubromazepam dependence. In addition, we observed several cardiotoxic effects of flubromazepam; 100-µM flubromazepam reduced cell viability, increased RR intervals but not QT intervals in the electrocardiography measurements, and considerably inhibited potassium channels in a human ether-à-go-go-related gene assay. Collectively, these findings suggest that flubromazepam may have adverse effects on psychological and cardiovascular health, laying the foundation for further efforts to list flubromazepam as a controlled substance at both national and international levels.

Alpinumisoflavone ameliorates choroidal neovascularisation and fibrosis in age-related macular degeneration in in vitro and in vivo models.

Age-related macular degeneration (AMD) is a major cause of vision loss in the elderly population. Anti-vascular endothelial growth factor (VEGF) antibody therapy is applicable to neovascularisation of AMD; however, the prevention of fibrosis after anti-VEGF monotherapy is an unmet medical need. Subretinal fibrosis causes vision loss in neovascular age-related macular degeneration (nAMD) even with anti-VEGF therapy. We report the anti-fibrotic and anti-neovascularisation effects of alpinumisoflavone (AIF), an isoflavonoid derived from unripe Maclura tricuspidata fruit, in in vitro and in vivo models. For in vitro study, we treated H2O2 or THP-1 conditioned media (TCM) following activation with phorbol 12-myristate 13-acetate (PMA) and lipopolysaccharide (LPS) in a human retinal pigment epithelial cell line (ARPE-19). Choroidal neovascularisation (CNV) was induced by laser photocoagulation in mice, immediately followed by intravitreal administration of 25 µg AIF. CNV area and fibrosis were measured 7 days after laser photocoagulation. AIF showed anti-fibrosis and anti-neovascularisation effects in both the models. The laser induced CNV area was reduced upon AIF administration in nAMD mouse model. Additionally, AIF decreased the levels of the cleaved form of crystallin alpha B (CRYAB), a chaperone associated with VEGF stabilisation and fibrosis. Our results demonstrate a novel therapeutic application of AIF against neovascularisation and fibrosis in nAMD.

Peroxiredoxin 6 Overexpression Induces Anxiolytic and Depression-Like Behaviors by Regulating the Serotonergic Pathway in Mice.

Peroxiredoxin 6 (PRDX6) is a bifunctional protein with both glutathione peroxidase and calcium-independent phospholipase activity. Recently, we reported that PRDX6 plays an important role in dopaminergic neurodegeneration in Parkinson's disease. However, the relationship between PRDX6 function and emotional behavior remains elusive. In the present study, we examined depression- and anxiety-like behaviors in PRDX6-overexpressing transgenic (PRDX6-Tg) mice using the forced swim test, tail suspension test, open field paradigm, and elevated plus-maze. PRDX6-Tg mice exhibited depression-like behaviors and low anxiety. In particular, female PRDX6-Tg mice exhibited anxiolytic behavior in the open field test. Furthermore, the serotonin content in the cortex and 5-hydroxytryptophan-induced head twitch response were both reduced in PRDX6-Tg mice. Interestingly, levels of dopa decarboxylase expression in the cortex were decreased in male PRDX6-Tg mice but not in female mice. Our findings provide novel insights into the role of PRDX6 in 5-HT synthesis and suggest that PRDX6 overexpression can induce depression-like behaviors via downregulation of the serotonergic neuronal system.

25I-NBOMe, a phenethylamine derivative, induces adverse cardiovascular effects in rodents: possible involvement of p21 (CDC42/RAC)-activated kinase 1.

Abuse of new psychoactive substances is an emerging social problem. Several phenethylamines are internationally controlled substances as they are likely to be abused and have adverse effects. Phenethylamine analog 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25I-NBOMe) has been reported as one of the most commonly abused psychoactive substance. However, the cardiotoxicity of this compound has not been extensively evaluated. Thus, in this study, we investigated the adverse cardiovascular effects of 25I-NBOMe, related to p21 (CDC42/RAC)-activated kinase 1 (PAK1). The cardiotoxicity of 25I-NBOMe was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, live/dead cytotoxicity assay, PAK1/CDC42 kinase assay, and in vivo electrocardiography (ECG). Also, we analyzed the expression level of PAK1, which is known to play key roles in the cardiovascular system. In the MTT assay, cell viability of 25I-NBOMe-treated H9c2 cells or primary cardiomyocytes of ICR mice decreased in a concentration-dependent manner. Results from the in vitro cytotoxicity assay in cardiomyocytes showed that 25I-NBOMe decreased the viability of H9c2 rat cardiomyocytes, and TC50 of 25I-NBOMe was found to be 70.4 µM. We also observed that 25I-NBOMe reduced PAK1 activity in vitro. Surface ECG measurement revealed that intravenous injection of 25I-NBOMe (doses of 1.0 and 3.0 mg/kg, corresponding to serum concentrations of 18.1 and 28.6 ng/mL, respectively) prolonged the QTc interval in SD rats. Furthermore, treatment with 25I-NBOMe downregulated the expression of PAK1 in the hearts of SD rats and H9c2 cells. In summary, our findings indicate that PAK1-related adverse effects of 25I-NBOMe can cause toxicity to cardiomyocytes and induce an abnormal ECG pattern in animals.

Cannabinoid Receptor Type 1 Regulates Drug Reward Behavior via Glutamate Decarboxylase 67 Transcription.

Interaction of cannabinoid receptor type 1 (CB1) and GABAergic neuronal activity is involved in drug abuse-related behavior. However, its role in drug-dependent Pavlovian conditioning is not well understood. In this study, we aimed to evaluate the effects of a CB1 agonist, JWH-210, on the development of conditioned place preference (CPP)-induced by methamphetamine (METH). Pretreatment with a synthetic cannabinoid, JWH-210 (CB1 agonist), increased METH-induced CPP score and METH-induced dopamine release in acute striatal slices. Interestingly, CB1 was expressed in glutamate decarboxylase 67 (GAD67) positive cells, and overexpression of CB1 increased GAD67 expression, while CB1 knockdown reduced GAD67 expression in vivo and in vitro. GAD67 is known as an enzyme involved in the synthesis of GABA. CB1 knockdown in the mice striatum increased METH-induced CPP. When GAD67 decreased in the mice striatum, mRNA level of CB1 did not change, suggesting that CB1 can regulate GAD67 expression. GAD67 knockdown in the mouse striatum augmented apomorphine (dopamine receptor D2 agonist)-induced climbing behavior and METH-induced CPP score. Moreover, in the human brain, mRNA level of GAD67 was found to be decreased in drug users. Therefore, we suggest that CB1 potentiates METH-induced CPP through inhibitory GABAergic regulation of dopaminergic neuronal activity.

D-limonene Inhibits Pentylenetetrazole-Induced Seizure via Adenosine A2A Receptor Modulation on GABAergic Neuronal Activity.

BACKGROUND: Epilepsy is a chronic neurological disorder characterized by the recurrence of seizures. One-third of patients with epilepsy may not respond to antiseizure drugs. PURPOSE: We aimed to examine whether D-limonene, a cyclic monoterpene, exhibited any antiseizure activity in the pentylenetetrazole (PTZ)-induced kindling mouse model and in vitro. METHODS: PTZ kindling mouse model was established by administering PTZ (30 mg/kg) intraperitoneally to mice once every 48 h. We performed immunoblot blots, immunohistochemistry (IHC), and high-performance liquid chromatography (HPLC) analysis after the behavioral study. RESULTS: An acute injection of PTZ (60 mg/kg) induced seizure in mice, while pretreatment with D-limonene inhibited PTZ-induced seizure. Repeated administration of PTZ (30 mg/kg) increased the seizure score gradually in mice, which was reduced in D-limonene (10 mg/kg)-pretreated group. In addition, D-limonene treatment increased glutamate decarboxylase-67 (GAD-67) expression in the hippocampus. Axonal sprouting of hippocampal neurons after kindling was inhibited by D-limonene pretreatment. Moreover, D-limonene reduced the expression levels of Neuronal PAS Domain Protein 4 (Npas4)-induced by PTZ. Furthermore, the adenosine A2A antagonist SCH58261 and ZM241385 inhibited anticonvulsant activity and gamma-aminobutyric acid (GABA)ergic neurotransmission-induced by D-limonene. CONCLUSION: These results suggest that D-limonene exhibits anticonvulsant activity through modulation of adenosine A2A receptors on GABAergic neuronal function.

Development of a Deep-Learning-Based Artificial Intelligence Tool for Differential Diagnosis between Dry and Neovascular Age-Related Macular Degeneration.

The use of deep-learning-based artificial intelligence (AI) is emerging in ophthalmology, with AI-mediated differential diagnosis of neovascular age-related macular degeneration (AMD) and dry AMD a promising methodology for precise treatment strategies and prognosis. Here, we developed deep learning algorithms and predicted diseases using 399 images of fundus. Based on feature extraction and classification with fully connected layers, we applied the Visual Geometry Group with 16 layers (VGG16) model of convolutional neural networks to classify new images. Image-data augmentation in our model was performed using Keras ImageDataGenerator, and the leave-one-out procedure was used for model cross-validation. The prediction and validation results obtained using the AI AMD diagnosis model showed relevant performance and suitability as well as better diagnostic accuracy than manual review by first-year residents. These results suggest the efficacy of this tool for early differential diagnosis of AMD in situations involving shortages of ophthalmology specialists and other medical devices.

Dopamine D1 receptor antagonist reduces stimulant-induced conditioned place preferences and dopamine receptor supersensitivity.

Repeated administration of stimulants induces conditioned place preference (CPP). Dopamine receptor supersensitivity is developed in stimulant-induced CPP animals; however, dopamine receptor subtypes associated with the development of supersensitivity in CPP animals are largely unknown. The present preclinical study aimed to examine whether dopamine D1 or D2 receptor antagonists exert inhibitory effects on stimulant-induced psychological behaviors. Additionally, the authors aimed to elucidate the role of dopamine receptor supersensitivity on the development of reward-related behavior. Sprague Dawley rats subjected to methamphetamine- and cocaine-induced CPP tests were treated with dopamine D1 (SCH23390) or D2 (sulpiride) receptor antagonists. Following the CPP experiment, rats were challenged with apomorphine (dopamine receptor agonist), and locomotor activity was measured. Methamphetamine- and cocaine-induced CPP was reduced with the administration of SCH23390, but not sulpiride. In addition, the apomorphine challenge evoked an increase in locomotor activity in stimulant-pre-treated rats, reflecting dopamine receptor supersensitivity. SCH23390 pre-treatment inhibited the development of dopamine receptor supersensitivity, while sulpiride demonstrated no inhibitory effects. These results suggest that the dopamine D1 receptor antagonist SCH23390 inhibits the development of dopamine receptor supersensitivity which is associated with the development of CPP.

Correction to: Dopamine D1 receptor antagonist reduces stimulant-induced conditioned place preferences and dopamine receptor supersensitivity.

In the originally published article, the name of the first author was incorrectly presented as Su Mi Gu. The correct name is Sun Mi Gu, which is also given above.

Limonene Inhibits Methamphetamine-Induced Sensitizations via the Regulation of Dopamine Receptor Supersensitivity.

Limonene is a cyclic terpene found in citrus essential oils and inhibits methamphetamine- induced locomotor activity. Drug dependence is a severe neuropsychiatric condition that depends in part on changes in neurotransmission and neuroadaptation, induced by exposure to recreational drugs such as morphine and methamphetamine. In this study, we investigated the effects of limonene on the psychological dependence induced by drug abuse. The development of sensitization, dopamine receptor supersensitivity, and conditioned place preferences in rats was measured following administration of limonene (10 or 20 mg/kg) and methamphetamine (1 mg/kg) for 4 days. Limonene inhibits methamphetamine- induced sensitization to locomotor activity. Expression of dopamine receptor supersensitivity induced by apomorphine, a dopamine receptor agonist, was significantly reduced in limonenepretreated rats. However, there was no significant difference in methamphetamine-induced conditioned place preferences between the limonene and control groups. These results suggest that limonene may ameliorate drug addiction-related behaviors by regulating postsynaptic dopamine receptor supersensitivity.

Methoxetamine Induces Cytotoxicity in H9c2 Cells: Possible Role of p21 Protein (Cdc42/Rac)-Activated Kinase 1.

The abuse of new psychoactive substances (NPS) is an emerging social problem. Methoxetamine, one of the NPS, was designed as an alternative to ketamine and it was considered an NPS candidate owing to its high addictive potential. However, cardiotoxicity of the phencyclidine analogue, methoxetamine, has not been extensively evaluated. P21 protein (Cdc42/Rac)-activated kinase 1 (PAK-1) is associated with the drug-induced cardiotoxicity and hypertrophy of cardiomyocytes. In the present study, we investigated the effects of methoxetamine on rat cardiomyocytes and PAK-1. Methoxetamine (at 10 µM) reduced cell viability and PAK-1 mRNA levels in H9c2 cells. Methoxetamine treatment (100 µM) decreased the beating rate of primary cardiomyocytes. However, 100 µM methoxetamine-induced heart rate decline was less than 100 µM PCP- or ketamine-induced heart rate decline. Meanwhile, fingolimod hydrochloride (FTY720, 1 µM), a PAK-1 activator, increased cell viability and inhibited hypertrophy induced by methoxetamine in H9c2 cells. These results suggest that methoxetamine may have harmful effects on the cardiovascular system through the regulation of the expression and function of PAK-1.

Piperlongumine Improves Lipopolysaccharide-Induced Amyloidogenesis by Suppressing NF-KappaB Pathway.

Amyloidogenesis is known to cause Alzheimer's disease. Our previous studies have found that lipopolysaccharide (LPS) causes neuroinflammation and amyloidogenesis through activation of nuclear factor kappaB (NF-κB). Piperlongumine (PL) is an alkaloid amide found naturally in long pepper (Piper longum) isolates; it was reported to have inhibitory effects on NF-κB activity. We therefore investigated whether PL exhibits anti-inflammatory and anti-amyloidogenic effects by inhibiting NF-κB. A murine model of LPS-induced memory impairment was made via the intraperitoneal (i.p.) injection of LPS (0.25 mg/kg/day, i.p.). We then injected PL (1.5 or 3.0 mg/kg/day, i.p.) for 7 days in three groups of mice to observe effects on memory. We also conducted an in vitro study with astrocytes and microglial BV-2 cells, which were treated with LPS (1 µg/mL) or PL (0.5 or 1.0 or 2.5 µM). Results from our behavioral tests showed that PL inhibited LPS-induced memory. PL also prevented LPS-induced beta-amyloid (Aß) accumulation and inhibited the activities of ß- and γ-secretases. The expression of inflammatory proteins also was decreased in PL-treated mice, cultured BV-2, and primary astrocyte cells. These effects were associated with the inhibition of NF-κB activity. A docking model analysis and pull-down assay showed that PL binds to p50. Taken together, our findings suggest that PL diminishes LPS-induced amyloidogenesis and neuroinflammation by inhibiting NF-κB signaling; PL therefore demonstrates potential for the treatment of Alzheimer's disease.

(E)-2-Methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) Phenol Ameliorates LPS-Mediated Memory Impairment by Inhibition of STAT3 Pathway.

Alzheimer's disease (AD) is pathologically characterized by an excessive accumulation of amyloid-beta (Aß) fibrils within the brain. We tested the anti-inflammatory and anti-amyloidogenic effects of (E)-2-methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) phenol (MMPP), a selective signal transducer and activator of transcription 3 (STAT3) inhibitor. We examined whether MMPP (5 mg/kg in drinking water for 1 month) prevents amyloidogenesis and cognitive impairment on AD model mice induced by intraperitoneal LPS (250 µg/kg daily 7 times) injections. Additionally, we investigated the anti-neuroinflammatory and anti-amyloidogenic effect of MMPP (1, 5, and 10 µg/mL) in LPS (1 µg/mL)-treated cultured astrocytes and microglial BV-2 cells. MMPP treatment reduced LPS-induced memory loss. This memory recovery effect was associated with the reduction of LPS-induced inflammatory proteins; cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) as well as activation of microglial cells and astrocytes in the brain. Furthermore, MMPP reduced LPS-induced ß-secretase and Aß generation. In in vitro study, LPS-induced expression of inflammatory proteins and amyloidogenic proteins was decreased in microglial BV-2 cells and cultured astrocytes by MMPP treatment. Moreover, MMPP treatment suppressed DNA binding activities of the activation of STAT3 in in vivo and in vitro. These results indicated that MMPP inhibits LPS-induced amyloidogenesis and neuroinflammation via inhibition of STAT3.

A synthetic cannabinoid JWH-210 reduces lymphoid organ weights and T-cell activator levels in mice via CB2 receptors.

The problem of new psychoactive substances (NPS) is emerging globally. However, the immunotoxicity of synthetic cannabinoids is not evaluated extensively yet. The purpose of the present study was to investigate whether synthetic cannabinoids (JWH-210 and JWH-030) induce adverse effects on lymphoid organs, viability of splenocytes and thymocytes, and immune cell activator and cytokines in mice. JWH-210 (10 mg/kg, 3 days, i.p.) is more likely to have cytotoxicity and reduce lymphoid organ weight than JWH-030 of ICR mice in vivo. We also demonstrated that JWH-210 administration resulted in the decrease of expression levels of T-cell activator including Cd3e, Cd3g, Cd74p31, and Cd74p41, while JWH-030 increased Cd3g levels. In addition, JWH-210 reduced expression levels of cytokines, such as interleukin-3, interleukin-5, and interleukin-6. Furthermore, we demonstrated that a CB2 receptor antagonist, AM630 inhibited JWH-210-induced cytotoxicity, whereas a CB1 receptor antagonist, rimonabant did not in primary cultured splenocytes. These results suggest that JWH-210 has a cytotoxicity via CB2 receptor action and results in decrement of lymphoid organ weights, T-cell activator, and cytokine mRNA expression levels.

Piperlongumine attenuates experimental autoimmune encephalomyelitis through inhibition of NF-kappaB activity.

Multiple sclerosis (MS) is a chronic, autoimmune and neurodegenerative disease in which demyelination sporadically and repeatedly occurs in the central nervous system (CNS). The activity of nuclear factor kappa B (NF-κB), a family of transcription factors, was increased in the cerebrospinal fluid (CSF) and/or the serum and brain and/or spinal cord of MS patients than in a healthy donors. In our study, we investigated whether piperlongumine (PL), which is known to have inhibitory effect on activity of NF-κB, can alleviate an experimental autoimmune encephalomyelitis (EAE). The mice were immunized with myelin oligodendrocyte glycoprotein 35-55 (MOG35-55), and then we injected PL (1.5mg/kg/day or 3.0mg/kg/day) into the mice intraperitoneally on every second day from days 2 to 28. For in vitro study, we treated PL (0.5, 1 and 2.5µM) to RAW 264.7 and Jurkat cells with each stimulator. We observed that the paralytic severity and neuropathology of EAE in PL-treated group were decreased compared with the EAE group. PL showed a suppressed effect on demyelination, immune cells infiltration, astrocytes/microglials activation, level of inflammatory cytokines and proteins as well as NF-κB activity. Production of inflammatory cytokines and proteins as well as translocation of NF-κB into nucleus by treatment stimulators in RAW 264.7 and Jurkat cells were reduced by PL. Moreover, treatment of NF-κB inhibitor further inhibited production of inflammatory cytokines and proteins. These results suggest that PL can mitigate MOG-induced EAE symptoms and activation of macrophages and T cells by inhibiting NF-κB signaling. Therefore, PL could be useful for the treatment for MS.

Synthetic Cannabinoid-Induced Immunosuppression Augments Cerebellar Dysfunction in Tetanus-Toxin Treated Mice.

Synthetic cannabinoids are one of most abused new psychoactive substances. The recreational use of abused drug has aroused serious concerns about the consequences of these drugs on infection. However, the effects of synthetic cannabinoid on resistance to tetanus toxin are not fully understood yet. In the present study, we aimed to determine if the administration of synthetic cannabinoids increase the susceptibility to tetanus toxin-induced motor behavioral deficit and functional changes in cerebellar neurons in mice. Furthermore, we measured T lymphocytes marker levels, such as CD8 and CD4 which against tetanus toxin. JWH-210 administration decreased expression levels of T cell activators including cluster of differentiation (CD) 3ε, CD3γ, CD74p31, and CD74p41. In addition, we demonstrated that JWH-210 induced motor impairment and decrement of vesicle-associated membrane proteins 2 levels in the cerebellum of mice treated with tetanus toxin. Furthermore, cerebellar glutamatergic neuronal homeostasis was hampered by JWH-210 administration, as evidenced by increased glutamate concentration levels in the cerebellum. These results suggest that JWH-210 may increase the vulnerability to tetanus toxin via the regulation of immune function.

Piperlongumine inhibits lung tumor growth via inhibition of nuclear factor kappa B signaling pathway.

Piperlongumine has anti-cancer activity in numerous cancer cell lines via various signaling pathways. But there has been no study regarding the mechanisms of PL on the lung cancer yet. Thus, we evaluated the anti-cancer effects and possible mechanisms of PL on non-small cell lung cancer (NSCLC) cells in vivo and in vitro. Our findings showed that PL induced apoptotic cell death and suppressed the DNA binding activity of NF-κB in a concentration dependent manner (0-15 µM) in NSCLC cells. Docking model and pull down assay showed that PL directly binds to the DNA binding site of nuclear factor-κB (NF-κB) p50 subunit, and surface plasmon resonance (SPR) analysis showed that PL binds to p50 concentration-dependently. Moreover, co-treatment of PL with NF-κB inhibitor phenylarsine oxide (0.1 µM) or p50 siRNA (100 nM) augmented PL-induced inhibitory effect on cell growth and activation of Fas and DR4. Notably, co-treatment of PL with p50 mutant plasmid (C62S) partially abolished PL-induced cell growth inhibition and decreased the enhanced expression of Fas and DR4. In xenograft mice model, PL (2.5-5 mg/kg) suppressed tumor growth of NSCLC dose-dependently. Therefore, these results indicated that PL could inhibit lung cancer cell growth via inhibition of NF-κB signaling pathway in vitro and in vivo.