Showing papers in "Journal of Neuroimmune Pharmacology in 2016"
TL;DR: The novelty-seeking trait can be valuable for predicting individual vulnerability to drug addiction and for generating successful treatment for patients with substance abuse disorders.
Abstract: Global treatment of drug addiction costs society billions of dollars annually, but current psychopharmacological therapies have not been successful at desired rates. The increasing number of individuals suffering from substance abuse has turned attention to what makes some people more vulnerable to drug addiction than others. One personality trait that stands out as a contributing factor is novelty seeking. Novelty seeking, affected by both genetic and environmental factors, is defined as the tendency to desire novel stimuli and environments. It can be measured in humans through questionnaires and in rodents using behavioral tasks. On the behavioral level, both human and rodent studies demonstrate that high novelty seeking can predict the initiation of drug use and a transition to compulsive drug use and create a propensity to relapse. These predictions are valid for several drugs of abuse, such as alcohol, nicotine, cocaine, amphetamine, and opiates. On the molecular level, both novelty seeking and addiction are modulated by the central reward system in the brain. Dopamine is the primary neurotransmitter involved in the overlapping neural substrates of both parameters. In sum, the novelty-seeking trait can be valuable for predicting individual vulnerability to drug addiction and for generating successful treatment for patients with substance abuse disorders.
107 citations
TL;DR: The results suggest that lupeol inhibits LPS-induced microglial neuroinflammation via the P38-MAPK and JNK pathways and has therapeutic potential to treat various neuroinflammatory disorders.
Abstract: Recent studies have demonstrated a close interaction between neuroinflammatory responses, increased production of inflammatory mediators, and neurodegeneration. Pathological findings in neurological diseases such as Alzheimer's disease, Parkinson's disease, and Huntington's disease have shown common signs of neuroinflammation and neurodegeneration. Lupeol, a natural pentacyclic triterpene, has revealed a number of pharmacological properties including an anti-inflammatory activity. This study aimed to evaluate the effect of lupeol against lipopolysaccharide (LPS)-induced neuroinflammation in the cortex and hippocampus of adult mice. Our results showed that systemic administration of LPS induced glial cell production of proinflammatory cytokines, tumor necrosis factor (TNF)-α, inducible nitric oxide synthase (iNOS), and interleukin (IL)-1β, while co-treatment with lupeol significantly inhibited the LPS-induced activation of microglia and astrocytes, and decreased the LPS-induced generation of TNF-α, iNOS, and IL-1β. The intracellular mechanism involved in the LPS-induced activation of inflammatory responses includes phosphorylation of P38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK), which was significantly inhibited by lupeol. We further elucidated that lupeol inhibited the LPS-induced activation of the mitochondrial apoptotic pathway and reversed the LPS-induced expression of apoptotic markers such as Bax, cytochrome C, caspase-9, and caspase-3. Taken together; our results suggest that lupeol inhibits LPS-induced microglial neuroinflammation via the P38-MAPK and JNK pathways and has therapeutic potential to treat various neuroinflammatory disorders.
90 citations
TL;DR: It is demonstrated that the novel mitochondria-targeted compound Mito-Apo exhibits profound neuroprotective effects in cellular and pre-clinical animal models of PD by attenuating oxidative damage and neuroinflammatory processes.
Abstract: Mitochondrial dysfunction, oxidative stress and neuroinflammation have been implicated as key mediators contributing to the progressive degeneration of dopaminergic neurons in Parkinson’s disease (PD). Currently, we lack a pharmacological agent that can intervene in all key pathological mechanisms, which would offer better neuroprotective efficacy than a compound that targets a single degenerative mechanism. Herein, we investigated whether mito-apocynin (Mito-Apo), a newly-synthesized and orally available derivative of apocynin that targets mitochondria, protects against oxidative damage, glial-mediated inflammation and nigrostriatal neurodegeneration in cellular and animal models of PD. Mito-Apo treatment in primary mesencephalic cultures significantly attenuated the 1-methyl-4-phenylpyridinium (MPP+)-induced loss of tyrosine hydroxylase (TH)-positive neuronal cells and neurites. Mito-Apo also diminished MPP+-induced increases in glial cell activation and inducible nitric oxide synthase (iNOS) expression. Additionally, Mito-Apo decreased nitrotyrosine (3-NT) and 4-hydroxynonenol (4-HNE) levels in primary mesencephalic cultures. Importantly, we assessed the neuroprotective property of Mito-Apo in the MPTP mouse model of PD, wherein it restored the behavioral performance of MPTP-treated mice. Immunohistological analysis of nigral dopaminergic neurons and monoamine measurement further confirmed the neuroprotective effect of Mito-Apo against MPTP-induced nigrostriatal dopaminergic neuronal loss. Mito-Apo showed excellent brain bioavailability and also markedly attenuated MPTP-induced oxidative markers in the substantia nigra (SN). Furthermore, oral administration of Mito-Apo significantly suppressed MPTP-induced glial cell activation, upregulation of proinflammatory cytokines, iNOS and gp91phox in IBA1-positive cells of SN. Collectively, these results demonstrate that the novel mitochondria-targeted compound Mito-Apo exhibits profound neuroprotective effects in cellular and pre-clinical animal models of PD by attenuating oxidative damage and neuroinflammatory processes.
84 citations
TL;DR: It is demonstrated that the elevated expression of pro-inflammatory cytokines in PTSD patients might be regulated by multiple epigenetic mechanisms and miRNAs.
Abstract: While Post Traumatic Stress Disorder (PTSD) is associated with immune dysfunction, the underlying mechanisms remain unclear. Studies suggest a role for involvement of epigenetic mechanisms and microRNAs (miRNAs). Here, we examined genome-wide histone and DNA methylation in the peripheral blood mononuclear cells (PBMCs) in PTSD. We noted significant differences in histone H3 trimethylation at K4, K9, K27 and K36 sites in PTSD when compared to control. While overall DNA methylation level did not differ significantly between control and PTSD, the promoters of several individual genes (e.g., Interferon gamma (IFNG) and Interleukin (IL)-12B) were differentially methylated. ChIP-seq data revealed that the promoter of IFNG and TBX-21 was associated with the activation marker H3K4me3 in PTSD. The transcript levels of both IFNG and TBX-21 were higher in PTSD correlating well with the altered methylation patterns. Furthermore, PTSD patients showed increased expression of IL-12 in their PBMCs. Analysis of both histone and DNA methylation markers suggested that the expression of IL-12 was also possibly activated through epigenetic modification. Knockdown of lysine (K)-specific demethylase 5B (KDM5B), or inhibition of DNA (Cytosine-5-)-methyltransferase 1 (DNMT1) caused up-regulation of IL-12. Furthermore, the expression of these cytokines was also regulated by miRNAs. Our miRNA microarray identified many downregulated miRNAs in PTSD that are predicted to target IFNG and IL-12. Consequently, we showed that up-regulation of hsa-miR-193a-5p could decrease the expression of IL-12. Overall, the current study demonstrated that the elevated expression of pro-inflammatory cytokines in PTSD patients might be regulated by multiple epigenetic mechanisms and miRNAs.
70 citations
TL;DR: It is indicated that miR-124 administration before the peak of the pro-inflammatory process of stroke is most effective in support of increasing the rehabilitation opportunity in the sub-acute phases of stroke.
Abstract: Mononuclear phagocytes respond to ischemic stroke dynamically, undergoing an early anti-inflammatory and protective phenotype followed by the pro-inflammatory and detrimental type. These dual roles of microglia/macrophages suggest the need of subtle adjustment of their polarization state instead of broad suppression. The most abundant brain-specific miRNA, miR-124, promotes neuronal differentiation but can also modulate microglia activation and keeps them in a quiescent state. We addressed whether the intracerebral injection of miR-124 in a mouse model of ischemic stroke before or after the peak phase of the pro-inflammatory polarization modifies the pro−/anti- inflammatory balance. In the sub-acute phase, 48 h after stroke, liposomated miR-124 shifted the predominantly pro-inflammatory polarized microglia/macrophages toward the anti-inflammatory phenotype. The altered immune response improved neurological deficit at day 6 after stroke. When miR-124 was injected 10 days after stroke, the pro−/anti- inflammatory ratio was still significantly reduced although to a lower degree and had no effect on recovery at day 14. This study indicates that miR-124 administration before the peak of the pro-inflammatory process of stroke is most effective in support of increasing the rehabilitation opportunity in the sub-acute phases of stroke. Our findings highlight the important role of immune cells after stroke and the therapeutic relevance of their polarization balance.
68 citations
TL;DR: The results of the present study demonstrate that tangeretin possesses a potent anti-inflammatory and antioxidant effect in microglia.
Abstract: Tangeretin, a flavonoid from citrus fruit peels, has been proven to play an important role in anti-inflammatory responses and neuroprotective effects in several disease models, but further study is necessary for elucidating the detailed mechanisms of these effects. In this study, we examined the anti-inflammatory effect of tangeretin in lipopolysaccharide (LPS)-stimulated microglia. We first observed that tangeretin inhibited LPS-induced production of nitric oxide, tumor necrosis factor alpha, interleukin (IL)-6, and IL-1β, as well as LPS-induced mRNA expression of inducible nitric oxide synthases and cytokines. Additionally, we found that the activities, mRNA levels, and protein levels of matrix metalloproteinase (MMP)-3 and MMP-8 were inhibited, while the expression of tissue inhibitor of metalloproteinase-2 was enhanced by tangeretin in LPS-stimulated microglia. Further mechanistic study showed that tangeretin suppressed LPS-induced phosphorylation of mitogen-activated protein kinases and Akt. Also, tangeretin inhibited nuclear factor-κB by upregulating sirtuin 1 and 5'-adenosine monophosphate-activated protein kinase. We further demonstrated the antioxidant effect of tangeretin by showing that tangeretin inhibited reactive oxygen species production and p47(phox) phosphorylation, while enhancing the expression of heme oxygenase-1 and the DNA binding activity of nuclear factor-erythroid 2-related factor 2 to the antioxidant response element in LPS-stimulated microglia. Taken together, the results of the present study demonstrate that tangeretin possesses a potent anti-inflammatory and antioxidant effect in microglia.
64 citations
TL;DR: The immune system, including microglia, may be a key link to understanding the etiology of fetal alcohol spectrum disorders and other unexplored cognitive or health risks associated with even low levels of Fetal alcohol exposure.
Abstract: During early brain development, microglial activation can negatively impact long-term neuroimmune and cognitive outcomes. It is well-known that significant alcohol exposure during early gestation results in a number of cognitive deficits associated with fetal alcohol spectrum disorders (FASD). Additionally, microglia are activated following high levels of alcohol exposure in rodent models of FASD. We sought to examine whether moderate prenatal alcohol exposure (70 mg/dL blood alcohol concentration) activates microglia in the fetal rat brain, and whether moderate fetal alcohol exposure has long-term negative consequences for immune function and cognitive function in the rat. We also measured inflammation within the placenta and maternal serum following moderate alcohol exposure to determine whether either could be a source of cytokine production in the fetus. One week of moderate prenatal alcohol exposure produced a sex-specific increase in cytokines and chemokines within the fetal brain. Cytokines were also increased within the placenta, regardless of the sex of the fetus, and independent of the low levels of circulating cytokines within the maternal serum. Adult offspring exposed to alcohol prenatally had exaggerated cytokine production in the brain and periphery in response to lipopolysaccharide (25 μg/kg), as well as significant memory deficits precipitated by this low-level of inflammation. Thus the immune system, including microglia, may be a key link to understanding the etiology of fetal alcohol spectrum disorders and other unexplored cognitive or health risks associated with even low levels of fetal alcohol exposure.
64 citations
TL;DR: The results suggest that dexmedetomidine postconditioning reduces HI-induced brain injury in the neonatal rats and may be mediated by α2 adrenergic receptor activation that inhibits inflammation in the ischemic brain tissues.
Abstract: Perinatal asphyxia can lead to death and severe disability. Brain hypoxia-ischemia (HI) injury is the major pathophysiology contributing to death and severe disability after perinatal asphyxia. Here, seven-day old Sprague-Dawley rats were subjected to left brain HI. Dexmedetomidine was given intraperitoneally after the brain HI. Yohimbine or atipamezole, two α2 adrenergic receptor antagonists, were given 10 min before the dexmedetomidine injection. Neurological outcome was evaluated 7 or 28 days after the brain HI. Frontal cerebral cortex was harvested 6 h after the brain HI. Left brain HI reduced the left cerebral hemisphere weight assessed 7 days after the brain HI. This brain tissue loss was dose-dependently attenuated by dexmedetomidine. Dexmedetomidine applied within 1 h after the brain HI produced this effect. Dexmedetomidine attenuated the brain HI-induced brain tissue and cell loss as well as neurological and cognitive dysfunction assessed from 28 days after the brain HI. Dexmedetomidine postconditioning-induced neuroprotection was abolished by yohimbine or atipamezole. Brain HI increased tumor necrosis factor α and interleukin 1β in the brain tissues. This increase was attenuated by dexmedetomidine. Atipamezole inhibited this dexmedetomidine effect. Our results suggest that dexmedetomidine postconditioning reduces HI-induced brain injury in the neonatal rats. This effect may be mediated by α2 adrenergic receptor activation that inhibits inflammation in the ischemic brain tissues.
64 citations
TL;DR: Results indicate a protective role of Apigenin against the neurodegenerative effects resulting from the entry of DC stimulated pathogenic T cells into the CNS thus implicating a potential therapy for neuroinflammatory disease.
Abstract: Apigenin, a natural flavonoid, found in several plants, fruits, vegetables, herbs, and spices, is known to have anti-oxidant and anti-inflammatory properties that are evident in the use of these substances for centuries as medicinal approaches to treat asthma, insomnia, Parkinson's disease, neuralgia, and shingles. However, there is a considerable dearth of information regarding its effect on immune cells, especially dendritic cells (DC) that maintain the critical balance between an immunogenic and tolerogenic immune response, in an immunospecialized location like the central nervous system (CNS). In this paper we looked at the anti-inflammatory properties of Apigenin in restoration of immune function and the resultant decrease in neuroinflammation. In vivo, a significant reduction in severity of experimental autoimmune encephalomyelitis (EAE) progression and relapse was observed in C57BL/6 (progressive) and SJL/J (relapse-remitting) mouse models of multiple sclerosis upon treatment with Apigenin. Apigenin treated EAE mice show decreased expression of α4 integrin and CLEC12A on splenic DCs and an increased retention of immune cells in the periphery compared to untreated EAE mice. This correlated consequently with immunohistochemistry findings of decreased immune cell infiltration and reduced demyelination in the CNS. These results indicate a protective role of Apigenin against the neurodegenerative effects resulting from the entry of DC stimulated pathogenic T cells into the CNS thus implicating a potential therapy for neuroinflammatory disease.
61 citations
TL;DR: This review introduces the nicotine metabolite ratio (NMR) as a reliable and stable phenotypic measure of nicotine metabolism that can guide smoking cessation treatment among smokers who wish to quit.
Abstract: Quitting smoking significantly reduces the risk of tobacco-related morbidity and mortality, yet there is a high rate of relapse amongst smokers who try to quit. Phenotypic biomarkers have the potential to improve smoking cessation outcomes by identifying the best available treatment for an individual smoker. In this review, we introduce the nicotine metabolite ratio (NMR) as a reliable and stable phenotypic measure of nicotine metabolism that can guide smoking cessation treatment among smokers who wish to quit. We address how the NMR accounts for sources of variation in nicotine metabolism including genotype and other biological and environmental factors such as estrogen levels, alcohol use, body mass index, or menthol exposure. Then, we highlight clinical trials that validate the NMR as a biomarker to predict therapeutic response to different pharmacotherapies for smoking cessation. Current evidence supports the use of nicotine replacement therapy for slow metabolizers, and non-nicotine treatments such as varenicline for normal metabolizers. Finally, we discuss future research directions to elucidate mechanisms underlying NMR associations with treatment response, and facilitate the implementation of the NMR as biomarker in clinical practice to guide smoking cessation.
55 citations
TL;DR: Results from human studies and animal (primarily HIV-1 gp120 transgenic mouse) models thus far suggest that combined HIV and Meth insults increase the likelihood of neural injury in the brain.
Abstract: Methamphetamine (Meth) use is frequent among HIV-infected persons. Combined HIV and Meth insults may exacerbate neural injury in vulnerable neuroanatomic structures or circuitries in the brain, leading to increased behavioral disturbance and cognitive impairment. While acute and chronic effects of Meth in humans and animal models have been studied for decades, the neurobehavioral effects of Meth in the context of HIV infection are much less explored. In-depth understanding of the scope of neurobehavioral phenotypes and mechanisms in HIV/Meth intersection is needed. The present report summarizes published research findings, as well as unpublished data, in humans and animal models with regard to neurobehavioral disturbance, neuroimaging, and neuropathology, and in vitro experimental systems, with an emphasis on findings emerging from the National Institute on Drug Abuse (NIDA) funded Translational Methamphetamine AIDS Research Center (TMARC). Results from human studies and animal (primarily HIV-1 gp120 transgenic mouse) models thus far suggest that combined HIV and Meth insults increase the likelihood of neural injury in the brain. The neurobehavioral effects include cognitive impairment and increased tendencies toward impaired behavioral inhibition and social cognition. These impairments are relevant to behaviors that affect personal and social risks, e.g. worse medication adherence, riskier behaviors, and greater likelihood of HIV transmission. The underlying mechanisms may include electrochemical changes in neuronal circuitries, injury to white matter microstructures, synaptodendritic damage, and selective neuronal loss. Utilization of research methodologies that are valid across species is instrumental in generating new knowledge with clinical translational value.
TL;DR: It is reported, here, that the conformation-specific antibody MC-1 produces some degree of improvement to both cognition and pathology in rTg4510, and this results support earlier reports in the initial review presented here, and collectively show promise for this strategy of treatment.
Abstract: Immunotherapy directed against tau is a promising treatment strategy for Alzheimer's Disease (AD) and tauopathies. We review initial studies on tau-directed immunotherapy, and present data from our laboratory testing antibodies using the rTg4510 mouse model, which deposits tau in forebrain neurons. Numerous antibodies have been tested for their efficacy in treating both pathology and cognitive function, in different mouse models, by different routes of administration, and at different ages or durations. We report, here, that the conformation-specific antibody MC-1 produces some degree of improvement to both cognition and pathology in rTg4510. Pathological improvements as measured by Gallyas staining for fully formed tangles and phosphorylated tau appeared 4 days after intracranial injection into the hippocampus. We also examined markers for microglial activation, which did not appear impacted from treatment. Behavioral effects were noted after continuous infusion of antibodies into the lateral ventricle for approximately 2 weeks. We examined basic motor skills, which were not impacted by treatment, but did note cognitive improvements with both novel object and radial arm water maze testing. Our results support earlier reports in the initial review presented here, and collectively show promise for this strategy of treatment. The general absence of extracellular tau deposits may avoid the opsonization and phagocytosis mechanisms activated by antibodies against amyloid, and make anti tau approaches a safer method of immunotherapy for Alzheimer's disease.
TL;DR: Data indicate that ABCA1-induced lipidation of ApoE is necessary for the ability of bexarotene to clear hippocampal soluble Aβ and ameliorate cognitive deficits.
Abstract: Alzheimer’s disease (AD) is characterized by impaired clearance of amyloid beta (Aβ) peptides, leading to the accumulation of Aβ in the brain and subsequent neurodegeneration and cognitive impairment. ApoE plays a critical role in the proteolytic degradation of soluble forms of Aβ. This effect is dependent upon lipidation of ApoE by ABCA1-mediated transfer of phospholipids and cholesterol. ApoE and ABCA1 are induced by the action of the RXR agonist, bexarotene. We have previously shown that bexarotene reduces Aβ levels in AD mouse models and we have hypothesized that this effect requires ABCA1-mediated lipidation of ApoE. To test this hypothesis, we crossed ABCA1-deficient (ABCA1 KO) mice with the APP/PS1 model of AD. Aged ABCA1 WT and ABCA1 KO APP/PS1 mice were treated for 7 days with vehicle or bexarotene (100 mg/kg/day). Bexarotene reduced levels of soluble Aβ 1–40 and 1–42 in the hippocampus of ABCA1 WT but not ABCA1 KO APP/PS1 mice. In contrast, insoluble levels of Aβ, and plaque loads were unaffected by bexarotene in this study. ABCA1 KO mice had increased levels of inflammation compared with ABCA1 WT mice. Bexarotene also increased most inflammatory gene markers evaluated. The effect of bexarotene on microglial inflammatory profiles, however, was independent of ABCA1 genotype. Importantly, bexarotene ameliorated deficits in novel object recognition in ABCA1 WT but not ABCA1 KO APP/PS1 mice. These data indicate that ABCA1-induced lipidation of ApoE is necessary for the ability of bexarotene to clear hippocampal soluble Aβ and ameliorate cognitive deficits.
TL;DR: Melatonin and NAS treatment significantly reduced the loss of mature oligodendrocytes, demyelination and axonal injury and significantly attenuated iNOS induction and reactive oxygen species (ROS) generation in lipopolysaccharide-activated microglia in culture.
Abstract: Melatonin and N-acetylserotonin (NAS) are tryptophan metabolites that have potent anti-oxidant, anti-inflammatory and neuroprotective properties in several animal models of neurological injury and disease including multiple sclerosis (MS). The therapeutic effect of NAS has not been reported previously in experimental autoimmune encephalomyelitis (EAE), a commonly used animal model of MS. Using a MOG-peptide induced EAE mouse model we examined the effects of melatonin and NAS on clinical score, inflammatory markers, free radical generation, and sparing of axons, oligodendrocytes and myelin. We found that NAS and melatonin reduced clinical scores when administered prior to or after symptom onset. This effect was more pronounced when melatonin and NAS were administrated prior to symptom onset whereby the appearance of motor symptoms was significantly delayed. Activated microglia and CD4+ T-cells were increased in the white matter of untreated EAE mice, with a return to near control levels after melatonin or NAS treatment. The expression of the NADPH oxidase component p67phox and inducible nitric oxide synthase (iNOS) was increased in the EAE mice as compared with controls, and both drug treated groups had significant reductions in their expression. Melatonin and NAS treatment significantly reduced the loss of mature oligodendrocytes, demyelination and axonal injury. Both compounds also significantly attenuated iNOS induction and reactive oxygen species (ROS) generation in lipopolysaccharide-activated microglia in culture. Our results show for the first time the therapeutic effects of NAS and confirm previous reports on the effectiveness of melatonin in the EAE model of MS.
TL;DR: Evidence is provided that intranasal delivery of ACEI may serve as an efficient alternative for their systemic administration, as it results in the attenuation of microglial accumulation and even the reduction of Amyloid β (Aβ) plaques.
Abstract: Angiotensin converting enzyme (ACE) converts Angiotensin I to a potent vasoconstrictor angiotensin II (ANG II). ACE inhibitors (ACEIs) are widely used for the management of hypertension. All components of the renin-angiotensin system (RAS) have also been identified in the brain. In addition to cytokines, neuromodulators such as ANG II can induce neuroinflammation. Moreover, in Alzheimer’s disease (AD) models, where neuroinflammation occurs and is thought to contribute to the propagation of the disease, increased levels of ANG II and ACE have been detected. However, the specific effect of ACEIs on neuroinflammation and AD remains obscure. The present study suggests that captopril and perindopril, centrally active ACEIs, may serve as modulators for microglial activation associated with AD. Our in vitro study investigated the effect of both ACEIs on nitric oxide (NO), tumor necrosis factor- α (TNF-α) release and inducible NO synthase (iNOS) expression in lipopolysaccharide (LPS)-induced BV2 microglia. Exposure of BV2 microglia to ACEIs significantly attenuated the LPS-induced NO and TNF-α release. In vivo, short term intranasal administration of perindopril or captopril to 5 Familial AD (5XFAD) mice significantly reduced amyloid burden and CD11b expression (a microglial marker) or only CD11b expression respectively, in the cortex of 5XFAD. Long-term intranasal administration of captopril to mice reduced amyloid burden with no effect on CD11b expression. We provide evidence that intranasal delivery of ACEI may serve as an efficient alternative for their systemic administration, as it results in the attenuation of microglial accumulation and even the reduction of Amyloid β (Aβ) plaques.
TL;DR: Urine exosome miRNAs hold the potential to be defined as novel accessible stage-specific biomarkers of EAE (MS) disease as well as treatment response and are found to be significantly altered in T cells polarized to Th1 and Th17 phenotype, similar to urine exosomes.
Abstract: Recently, microRNAs (miRNAs) have been implicated in regulating neuroinflammatory and demyelinative responses in multiple sclerosis (MS) and its mouse model of experimental autoimmune encephalomyelitis (EAE). miRNAs have also been studied as biomarkers of disease pathology and drug-response in MS. However, no complete miRNA profiling at various stages of EAE disease has been examined, especially in the urine. We carried out a systematic analysis of miRNAs in the urine exosomes as well as in the plasma and spinal cord at pre-onset, onset and peak stages of EAE established in the chronic B6 mice model. For the first time, we provide evidence that urine exosomes can be a specific and sensitive source of miRNA biomarkers for all 3 stages of EAE disease. In a significant observation, we observed that miR-155-5p expression increased in urine exosomes, plasma and spinal cord 6 days before the onset of disease, suggesting its early involvement in the pathology of EAE disease. We also analyzed the effect of Glatiramer acetate (GA; copaxone) treatment, an approved treatment for MS patients, in modulating miRNA expression at the peak of EAE disease. We identified miR-155-5p, miR-27a-3p, miR-9-5p and miR-350-5p as putative GA-treatment responsive miRNA biomarkers. Since, EAE is a mainly CD4 cells mediated disease, we also examined the above set of miRNAs and found to be significantly altered in T cells polarized to Th1 and Th17 phenotype, similar to urine exosomes. Thus, urine exosome miRNAs hold the potential to be defined as novel accessible stage-specific biomarkers of EAE (MS) disease as well as treatment response.
TL;DR: The regional localization of CXCR7 receptors in adult mouse brain is investigated and it is found that the receptors were expressed in various brain regions including olfactory bulb, cerebral cortex, hippocampus, subventricular zone (SVZ), hypothalamus and cerebellum.
Abstract: The chemokine stromal cell-derived factor-1 (SDF-1)/CXCL12 acting via its G-protein coupled receptor (GPCR) CXCR4 has been implicated in neurogenesis, neuromodulation, brain inflammation, HIV-1 encephalopathy and tumor growth. CXCR7 was identified as an alternate receptor for SDF-1/CXCL12. Characterization of CXCR7-deficient mice demonstrated a role for CXCR7 in fetal endothelial biology, cardiac development, and B-cell localization. Despite its ligand binding properties, CXCR7 does not seem to signal like a conventional GPCR. It has been suggested that CXCR7 may not function alone but in combination with CXCR4. Here, we investigated the regional localization of CXCR7 receptors in adult mouse brain using CXCR7-EGFP transgenic mice. We found that the receptors were expressed in various brain regions including olfactory bulb, cerebral cortex, hippocampus, subventricular zone (SVZ), hypothalamus and cerebellum. Extensive CXCR7 expression was associated with cerebral blood vessels. Using cell type specific markers, CXCR7 expression was found in neurons, astrocytes and oligodendrocyte progenitors. GAD-expressing neurons exhibited CXCR7 expression in the hippocampus. Expression of CXCR7 in the dentate gyrus included cells that expressed nestin, GFAP and cells that appeared to be immature granule cells. In mice with Experimental Autoimmune Encephalomyelitis (EAE), CXCR7 was expressed by migrating oligodendrocyte progenitors in the SVZ. We then compared the distribution of SDF-1/CXCL12 and CXCR7 using bitransgenic mice expressing both CXCR7-EGFP and SDF-1-mRFP. Enhanced expression of SDF-1/CXCL12 and CXCR7 was observed in the corpus callosum, SVZ and cerebellum. Overall, the expression of CXCR7 in normal and pathological nervous system suggests CXCR4-independent functions of SDF-1/CXCL12 mediated through its interaction with CXCR7.
TL;DR: This report represents the first report of the therapeutic benefit of B-cell depletion in the development and progression of CCMs, and provides a proof of principle that B cells play a critical role in CCM lesion genesis and maturation.
Abstract: Cerebral cavernous malformations (CCMs) are relatively common vascular malformations, characterized by increased Rho kinase (ROCK) activity, vascular hyper-permeability and the presence of blood degradation products including non-heme iron. Previous studies revealed robust inflammatory cell infiltration, selective synthesis of IgG, in situ antigen driven B-cell clonal expansion, and deposition of immune complexes and complement proteins within CCM lesions. We aimed to evaluate the impact of suppressing the immune response on the formation and maturation of CCM lesions, as well as lesional iron deposition and ROCK activity. Two murine models of heterozygous Ccm3 (Pdcd10), which spontaneously develop CCM lesions with severe and milder phenotypes, were either untreated or received anti-mouse BR3 to deplete B cells. Brains from anti-mouse BR3-treated mice exhibited significantly fewer mature CCM lesions and smaller lesions compared to untreated mice. B cell depletion halted the progression of lesions into mature stage 2 lesions but did not prevent their genesis. Non-heme iron deposition and ROCK activity was decreased in lesions of B cell depleted mice. This represents the first report of the therapeutic benefit of B-cell depletion in the development and progression of CCMs, and provides a proof of principle that B cells play a critical role in CCM lesion genesis and maturation. These findings add biologics to the list of potential therapeutic agents for CCM disease. Future studies would characterize the putative antigenic trigger and further define the mechanism of immune response in the lesions.
TL;DR: Safety data of almost 50 patient years of treatment with rituximab show that ritukimab is tolerated well in MS/NMO patients, and may help the individual physician to balance efficacy of ritUXimab against the risk.
Abstract: Introduction
Multiple sclerosis (MS) is an immune-mediated disease. Over the last decades therapeutic options have broadened tremendously. Nevertheless, various therapeutic agents, e.g., rituximab, are currently used in the treatment of MS off label. Disease or health registries are useful methods to collect information about off-label treatments. The German registry for autoimmune disease (GRAID) is a multicenter, retrospective, non-interventional database of patients with various autoimmune diseases.
TL;DR: The results indicate that the COMT Val158Met polymorphism is a vulnerability factor for MDD with distinct effects in different ethnic populations.
Abstract: The COMT (catechol-O-methyltransferase) Val158Met polymorphism (rs4680) is a potential susceptibility variant for major depressive disorder (MDD). Although many genetic studies have examined the association between MDD and this polymorphism, the results were inconclusive. In the present study, we conducted a series of meta-analyses of samples consisting of 2905 MDD cases and 2403 controls with the goal of determining whether this variant indeed has any effect on MDD. We revealed a significant association in the comparison of Val/Val + Val/Met vs. Met/Met (OR =1.180; 95 % CI = 1.019, 1.367; P = 0.027), Val/Met vs. Val/Val (OR =1.18; 95 % CI = 1.038, 1.361; P = 0.013), and Val/Met vs. Met/Met (OR =1.229; 95 % CI = 1.053, 1.435; P = 0.009). Further meta-analyses of samples with European ancestry demonstrated a significant association of this SNP with MDD susceptibility in Val/Val + Val/Met vs. Met/Met (OR =1.231, 95 % CI = 1.046, 1.449; P = 0.013) and Val/Met vs. Met/Met (OR =1.284, 95 % CI = 1.050, 1.484; P = 0.012). For the samples with East Asian ancestry, we found a significant association in both allelic (Val vs. Met: OR =0.835; 95 % CI = 0.714, 0.975; P = 0.023) and genotypic (Met/Met + Val/Met vs. Val/Val: OR =1.431, 95 % CI = 1.143, 1.791; P = 0.002; Val/Met vs. Val/Val: OR =1.482, 95 % CI = 1.171, 1.871; P = 0.001) analyses. No evidence of heterogeneity among studies or publication bias was observed. Together, our results indicate that the COMT Val158Met polymorphism is a vulnerability factor for MDD with distinct effects in different ethnic populations.
TL;DR: In this review, neuroprotective aspects of mitochondrial quality control proteases and neuropathological manifestations arising from defective proteolysis within the mitochondrion are discussed.
Abstract: The functional integrity of mitochondria is a critical determinant of neuronal health and compromised mitochondrial function is a commonly recognized factor that underlies a plethora of neurological and neurodegenerative diseases. Metabolic demands of neural cells require high bioenergetic outputs that are often associated with enhanced production of reactive oxygen species. Unopposed accumulation of these respiratory byproducts over time leads to oxidative damage and imbalanced protein homeostasis within mitochondrial subcompartments, which in turn may result in cellular demise. The post-mitotic nature of neurons and their vulnerability to these stress factors necessitate strict protein homeostatic control to prevent such scenarios. A series of evolutionarily conserved proteases is one of the central elements of mitochondrial quality control. These versatile proteolytic enzymes conduct a multitude of activities to preserve normal mitochondrial function during organelle biogenesis, metabolic remodeling and stress. In this review we discuss neuroprotective aspects of mitochondrial quality control proteases and neuropathological manifestations arising from defective proteolysis within the mitochondrion.
TL;DR: The results indicate that exposing human and rat primary hippocampal neurons to cocaine and HIV-1 Tat synergistically decreased both mitochondrial membrane potential and ATP production, indicating the possible involvement of the Parkin/PINK1/DJ-1 (PPD) complex in neuronal degeneration.
Abstract: Addictive stimulant drugs, such as cocaine, are known to increase the risk of exposure to HIV-1 infection and hence predispose towards the development of AIDS. Previous findings suggested that the combined effect of chronic cocaine administration and HIV-1 infection enhances cell death. Neuronal survival is highly dependent on the health of mitochondria providing a rationale for assessing mitochondrial integrity and functionality following cocaine treatment, either alone or in combination with the HIV-1 viral protein Tat, by monitoring ATP release and mitochondrial membrane potential (ΔΨm). Our results indicate that exposing human and rat primary hippocampal neurons to cocaine and HIV-1 Tat synergistically decreased both mitochondrial membrane potential and ATP production. Additionally, since previous studies suggested HIV-1 infection alters autophagy in the CNS, we investigated how HIV-1 Tat and cocaine affect autophagy in neurons. The results indicated that Tat induces an increase in LC3-II levels and the formation of Parkin-ring-like structures surrounding damaged mitochondria, indicating the possible involvement of the Parkin/PINK1/DJ-1 (PPD) complex in neuronal degeneration. The importance of mitochondrial damage is also indicated by reductions in mitochondrial membrane potential and ATP content induced by HIV-1 Tat and cocaine.
TL;DR: The data show that in the mouse brain extracellular mitochondria and its components can induce neuroinflammation,extracellular mtDNA or mtDNA-associated proteins can contribute to this effect, and mitochondria derived-DAMP molecules can influence AD-associated biomarkers.
Abstract: Mitochondria and mitochondrial debris are found in the brain’s extracellular space, and extracellular mitochondrial components can act as damage associated molecular pattern (DAMP) molecules. To characterize the effects of potential mitochondrial DAMP molecules on neuroinflammation, we injected either isolated mitochondria or mitochondrial DNA (mtDNA) into hippocampi of C57BL/6 mice and seven days later measured markers of inflammation. Brains injected with whole mitochondria showed increased Tnfα and decreased Trem2 mRNA, increased GFAP protein, and increased NFκB phosphorylation. Some of these effects were also observed in brains injected with mtDNA (decreased Trem2 mRNA, increased GFAP protein, and increased NFκB phosphorylation), and mtDNA injection also caused several unique changes including increased CSF1R protein and AKT phosphorylation. To further establish the potential relevance of this response to Alzheimer’s disease (AD), a brain disorder characterized by neurodegeneration, mitochondrial dysfunction, and neuroinflammation we also measured App mRNA, APP protein, and Aβ1–42 levels. We found mitochondria (but not mtDNA) injections increased these parameters. Our data show that in the mouse brain extracellular mitochondria and its components can induce neuroinflammation, extracellular mtDNA or mtDNA-associated proteins can contribute to this effect, and mitochondria derived-DAMP molecules can influence AD-associated biomarkers.
TL;DR: The differential expression of plasma miRNAs in 124 patients with methamphetamine (MA) use disorders was investigated and it was found that the expression of miR181a, miR15b,miR- let-7e,MiR-let-7d in plasma were decreased compared to normal controls, and could serve as a potential peripheral biomarker for MA use disorder when confirmed by future studies.
Abstract: Recent research have revealed that circulating miRNAs may offer noninvasive biomarkers for human disease, offering the prospect for earlier diagnosis, and improved precision of diagnoses. The diagnoses of drug use disorders is still mainly based on subjective report and no objective biomarkers available. Many animal and cell studies found that miRNAs were involved in substance use disorders, including alcohol, morphine, cocaine and amphetamine use disorders. However, no study on circulating miRNAs for drug use disorders so far. We investigated the differential expression of plasma miRNAs in 124 patients with methamphetamine (MA) use disorders. Based on the preliminary results from microarray screen, plasma expression of 6 candidate miRNAs were measured by Quantitative real-time RT-PCR. We found that the expression of miR181a, miR15b, miR- let-7e, miR- let-7d in plasma were decreased compared to normal controls. The expression of the altered miRNAs were negative correlated with drug use frequencies in past months. Our findings suggested that miR-181a, miR-15b, miR-let-7e and miR-let-7d may play a potential role in the pathology of MA use disorder, and could serve as a potential peripheral biomarker for MA use disorder when confirmed by future studies. Further study are needed to elucidate the molecular mechanism modulated by miRNAs and explore potential novel intervention targets.
TL;DR: A consistent finding for the effectiveness of therapeutic interventions identifies the improvement of executive control networks and the dampening of limbic activation, highlighting their values as targets for therapeutic interventions in substance use disorders.
Abstract: Neuroimaging techniques to measure the function and biochemistry of the human brain such as positron emission tomography (PET), proton magnetic resonance spectroscopy ((1)H MRS), and functional magnetic resonance imaging (fMRI), are powerful tools for assessing neurobiological mechanisms underlying the response to treatments in substance use disorders. Here, we review the neuroimaging literature on pharmacological and behavioral treatment in substance use disorder. We focus on neural effects of medications that reduce craving (e.g., naltrexone, bupropion hydrochloride, baclofen, methadone, varenicline) and that improve cognitive control (e.g., modafinil, N-acetylcysteine), of behavioral treatments for substance use disorders (e.g., cognitive bias modification training, virtual reality, motivational interventions) and neuromodulatory interventions such as neurofeedback and transcranial magnetic stimulation. A consistent finding for the effectiveness of therapeutic interventions identifies the improvement of executive control networks and the dampening of limbic activation, highlighting their values as targets for therapeutic interventions in substance use disorders.
TL;DR: Screening, early intervention, and continued scaling up of therapeutic options are critical for effective control or continued reduction of drug abuse and co-infections in Asian countries.
Abstract: Drug abuse and co-occurring infections are associated with significant morbidity and mortality. Asian countries are particularly vulnerable to the deleterious consequences of these risks/problems, as they have some of the highest rates of these diseases. This review describes drug abuse, HIV, and hepatitis C (HCV) in Asian countries. The most commonly used illicit drugs include opioids, amphetamine-type stimulants (ATS), cannabis, and ketamine. Among people who inject drugs, HIV rates range from 6.3 % in China to 19 % in Malaysia, and HCV ranges from 41 % in India and Taiwan to 74 % in Vietnam. In the face of the HIV epidemics, drug policies in these countries are slowly changing from the traditional punitive approach (e.g., incarcerating drug users or requiring registration as a drug user) to embrace public health approaches, including, for example, community-based treatment options as well as harm reduction approaches to reduce needle sharing and thus HIV transmission. HIV and HCV molecular epidemiology indicates limited geographic diffusion. While the HIV prevalence is declining in all five countries, use of new drugs (e.g., ATS, ketamine) continues to increase, as well as high-risk sexual behaviors associated with drug use—increasing the risk of sexual transmission of HIV, particularly among men who have sex with men. Screening, early intervention, and continued scaling up of therapeutic options (drug treatment and recovery support, ART, long-term HIV and HCV care for drug users) are critical for effective control or continued reduction of drug abuse and co-infections.
TL;DR: A cell-autonomous anti-inflammatory effect of ADX88178 mediated mGlu4 activation on microglia is demonstrated, suggesting that this drug or similar activators or potentiators of mGLU4 may have disease-modifying as well as symptomatic effects in PD and other brain disorders with an inflammatory component.
Abstract: While the specific trigger of Parkinson Disease (PD) in most patients is unknown, considerable evidence suggests that the neuroinflammatory response makes an essential contribution to the neurodegenerative process. Drugs targeting metabotropic glutamate receptors (mGlu receptors), 7 Transmembrane (7TM) spanning/G protein coupled receptors that bind glutamate, are emerging as therapeutic targets for PD and may have anti-inflammatory properties. ADX88178 is novel potent, selective, and brain-penetrant positive allosteric modulator of the mGlu4 which is under evaluation for treatment of PD and other neurological disorders. We used microglia cultured from mouse brain to determine if ADX88178 had direct effects on the inflammatory responses of these cells. We studied both microglia from wild type and Grm4 knock out mice. We found that activation of mGlu4 with ADX88178 attenuated LPS-induced inflammation in primary microglia, leading to a decrease in the expression of TNFα, MHCII, and iNOS, markers of pro-inflammatory responses. These effects were absent in microglia from mice lacking mGlu4. These results demonstrate a cell-autonomous anti-inflammatory effect of ADX88178 mediated mGlu4 activation on microglia, and suggest that this drug or similar activators or potentiators of mGlu4 may have disease-modifying as well as symptomatic effects in PD and other brain disorders with an inflammatory component.
TL;DR: It is concluded that abnormally low expression of GABAergic markers is prevalent in HIV-1 infected patients, and relationships with other neurotransmitter systems including dopaminergic transmission and with endothelial cell markers lend added support to suggestions that synaptic plasticity and cerebrovascular anomalies are involved with HAND in virally suppressed patients.
Abstract: The prevalence of HIV-associated neurocognitive disorders (HAND) remains high in patients with effective suppression of virus replication by combination antiretroviral therapy (cART). Several neurotransmitter systems were reported to be abnormal in HIV-infected patients, including the inhibitory GABAergic system, which mediates fine-tuning of neuronal processing and plays an essential role in cognitive functioning. To elucidate the role of abnormal GABAergic transmission in HAND, the expression of GABAergic markers was measured in 449 human brain specimens from HIV-infected patients with and without HAND. Using real-time polymerase chain reaction, immunoblotting and immunohistochemistry we found that the GABAergic markers were significantly decreased in most sectors of cerebral neocortex, the neostriatum, and the cerebellum of HIV-infected subjects. Low GABAergic expression in frontal neocortex was correlated significantly with high expression of endothelial cell markers, dopamine receptor type 2 (DRD2L), and preproenkephalin (PENK) mRNAs, and with worse performance on tasks of verbal fluency. Significant associations were not found between low GABAergic mRNAs and HIV-1 RNA concentration in the brain, the history of cART, or HIV encephalitis. Pathological evidence of neurodegeneration of the affected GABAergic neurons was not present. We conclude that abnormally low expression of GABAergic markers is prevalent in HIV-1 infected patients. Interrelationships with other neurotransmitter systems including dopaminergic transmission and with endothelial cell markers lend added support to suggestions that synaptic plasticity and cerebrovascular anomalies are involved with HAND in virally suppressed patients.
TL;DR: Findings from Malaysia’s largest prison are reviewed to describe the negative synergistic effects of HIV, tuberculosis, addiction, and incarceration that contribute to a ‘perfect storm’ of events challenging public and personal health and offer insights into innovative strategies to control these converging epidemics.
Abstract: Throughout Southeast Asia, repressive drug laws have resulted in high rates of imprisonment in people who inject drugs (PWID) and people living with HIV (PLH), greatly magnifying the harm associated with HIV, tuberculosis, and addiction. We review findings from Malaysia’s largest prison to describe the negative synergistic effects of HIV, tuberculosis, addiction, and incarceration that contribute to a ‘perfect storm’ of events challenging public and personal health and offer insights into innovative strategies to control these converging epidemics. The majority of PLH who are imprisoned in Malaysia are opioid dependent PWID. Although promoted by official policy, evidence-based addiction treatment is largely unavailable, contributing to rapid relapse and/or overdose after release. Similarly, HIV treatment in prisons and compulsory drug treatment centers is sometimes inadequate or absent. The prevalence of active tuberculosis is high, particularly in PLH, and over 80 % of prisoners and prison personnel are latently infected. Mandatory HIV testing and subsequent segregation of HIV-infected prisoners increases the likelihood of tuberculosis acquisition and progression to active disease, amplifying the reservoir of infection for other prisoners. We discuss strategies to control these intersecting epidemics including screening linked to standardized treatment protocols for all three conditions, and effective transitional programs for released prisoners. For example, recently introduced evidence-based interventions in prisons like antiretroviral therapy (ART) to treat HIV, isoniazid preventive therapy to treat latent tuberculosis infection, and methadone maintenance to treat opioid dependence, have markedly improved clinical care and reduced morbidity and mortality. Since introduction of these interventions in September 2012, all-cause and HIV-related mortality have decreased by 50.0 % and 75.7 %, respectively. We discuss the further deployment of these interventions in Malaysian prisons.
TL;DR: The study results suggest a general acceptance of S-Health, but also indicate cultural variations in access to therapeutic and other social support systems, legal repercussions of substance use, societal perceptions of addiction, and the role of family and othersocial support in recovery.
Abstract: Smartphone-based interventions are increasingly used to support self-monitoring, self-management, and treatment and medication compliance in order to improve overall functioning and well-being. In attempting to develop a smartphone application (S-Health) that assists heroin-dependent patients in recovery, a series of focus groups (72 patients, 22 providers) were conducted in China, Taiwan, and the USA to obtain their perspectives on its acceptance and potential adoption. Data were analyzed according to the Diffusion of Innovation (DOI) theory of characteristics important to the adoption of innovation. Important to Relative Advantage, USA participants cited S-Health’s potential ability to overcome logistical barriers, while those in China and Taiwan valued its potential to supplement currently limited services. In terms of Compatibility, participants across sites reported recovery needs and goals that such an application could be helpful in supporting; however, its utility during strong craving was questioned in China and Taiwan. Important factors relevant to Complexity included concerns about smartphone access and familiarity, individualization of content, and particularly in China and Taiwan, participants wanted assurance of privacy and security. The study results suggest a general acceptance, but also indicate cultural variations in access to therapeutic and other social support systems, legal repercussions of substance use, societal perceptions of addiction, and the role of family and other social support in recovery. Taking these factors into consideration is likely to increase diffusion as well as effectiveness of these smartphone-based interventions.