Effects of the anti-multiple sclerosis immunomodulator laquinimod on anxiety and depression in rodent behavioral models

Comparing the effect of fluoxetine, escitalopram, and sertraline, on the level of BDNF and depression in preclinical and clinical studies: a systematic review

Brain-derived neurotrophic factor (BDNF) dysfunction is one of the most important mechanisms underlying depression. It seems that selective serotonin reuptake inhibitors (SSRIs) improve depression via affecting BDNF level. In this systematic review, for the first time, we aimed to review the effect of three SSRIs including fluoxetine, escitalopram, and sertraline, on both depression and BDNF level in preclinical and clinical studies. PubMed electronic database was searched, and 193 articles were included in this study. After reviewing all manuscripts, only one important difference was found: subjects. We found that SSRIs induce different effects in animals vs. humans. Preclinical studies showed many controversial effects, while human studies showed only two effects: improvement of depression, with or without the improvement of BDNF. However, most studies used chronic SSRIs treatment, while acute SSRIs were not effectively used and evaluated. In conclusion, it seems that SSRIs are reliable antidepressants, and the improvement effect of SSRIs on depression is not dependent to BDNF level (at least in human studies).

Molecular Effects of FDA-Approved Multiple Sclerosis Drugs on Glial Cells and Neurons of the Central Nervous System

Multiple sclerosis (MS) is characterized by peripheral and central inflammatory features, as well as demyelination and neurodegeneration. The available Food and Drug Administration (FDA)-approved drugs for MS have been designed to suppress the peripheral immune system. In addition, however, the effects of these drugs may be partially attributed to their influence on glial cells and neurons of the central nervous system (CNS). We here describe the molecular effects of the traditional and more recent FDA-approved MS drugs Fingolimod, Dimethyl Fumarate, Glatiramer Acetate, Interferon-β, Teriflunomide, Laquinimod, Natalizumab, Alemtuzumab and Ocrelizumab on microglia, astrocytes, neurons and oligodendrocytes. Furthermore, we point to a possible common molecular effect of these drugs, namely a key role for NFκB signaling, causing a switch from pro-inflammatory microglia and astrocytes to anti-inflammatory phenotypes of these CNS cell types that recently emerged as central players in MS pathogenesis. This notion argues for the need to further explore the molecular mechanisms underlying MS drug action.

4-phenylselenyl-7-chloroquinoline, a novel multitarget compound with anxiolytic activity: Contribution of the glutamatergic system

A growing body of evidence demonstrates that quinoline compounds have attracted much attention in the field of drug development. Accordingly, 4-phenylselenyl-7-chloroquinoline (4-PSQ) is a new quinoline derivative containing selenium, which showed a potential antioxidant, antinociceptive and anti-inflammatory effect. The present study was undertaken to evaluate the anxiolytic-like properties of 4-PSQ. Mice were orally pretreated with 4-PSQ (5-50 mg/kg) or vehicle, 30 min prior to the elevated plus-maze (EPM), light-dark (LDT) or open field (OFT) tests. A time-response curve was carried out by administration of 4-PSQ (50 mg/kg) at different times before the EPM test. The involvement of glutamate uptake/release and Na⁺, K⁺-ATPase activity in the anxiolytic-like effect was investigated in cerebral cortices. In addition, the effectiveness of acute treatment with 4-PSQ was evaluated in a model of kainate (KA)-induced anxiety-related behavior. Finally, acute toxicity of this compound was investigated. 4-PSQ produced an anxiolytic-like action, both in EPM and LDT. In OFT, 4-PSQ did not affect locomotor and exploratory activities. 4-PSQ anxiolytic-like effect started at 0.5 h and remained significant up to 72 h after administration. Treatment with 4-PSQ reduced [³H] glutamate uptake, but the [³H] glutamate release and Na⁺, K⁺-ATPase activity were not altered. KA-induced anxiety-related behavior was protected by 4-PSQ pretreatment. Additionally, 4-PSQ exposure did not alter urea levels, aspartate (AST) and alanine aminotrasferase (ALT) activities in plasma. Parameters of oxidative stress in brain and liver of mice were not modified by 4-PSQ. Taken together these data demonstrated that the anxiolytic-like effect caused by 4-PSQ seems to be mediated by involvement of the glutamatergic system.

Laquinimod rescues striatal, cortical and white matter pathology and results in modest behavioural improvements in the YAC128 model of Huntington disease

Increasing evidence supports a role for abnormal immune activation and inflammatory responses in Huntington disease (HD). In this study, we evaluated the therapeutic potential of laquinimod (1 and 10 mg/kg), a novel immunomodulatory agent shown to be protective in a number of neuroinflammatory conditions, in the YAC128 mouse model of HD. Treatment with laquinimod for 6 months rescued atrophy in the striatum, in certain cortical regions, and in the corpus callosum of YAC128 HD mice. Diffusion tensor imaging showed that white matter microstructural abnormalities in the posterior corpus callosum were improved following treatment with low dose (1 mg/kg) laquinimod, and were paralleled by reduced levels of interleukin-6 in the periphery of YAC128 HD mice. Functionally, treatment with laquinimod (1 and 10 mg/kg) led to modest improvements in motor function and in depressive-like behaviour. Taken together, these results suggest that laquinimod may improve some features of pathology in HD, and provides support for the role of immune activation in the pathogenesis of HD.