Inflammation modulates anxiety in an animal model of multiple sclerosis.
ABSTRACT Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by inflammation, but also degenerative changes. Besides neurological deficits, the rate of affective disorders such as depression and anxiety is at least six fold increased. Many aspects of MS can be mimicked in the animal model of myelin oligodendrocyte glycoprotein experimental autoimmune encephalomyelitis (MOG-EAE). Here we investigate behavioral changes in C57BL/6 mice suffering from mild MOG-EAE. In the later phase of the disease, mice were subjected to behavioral tests including the light-dark-box (LD Box), the acoustic startle response (SR) with a pre-pulse inhibition protocol as well as the learned helplessness (LH) paradigm. Behavioral data were correlated with the motor performance in an open field and rotarod test (RR). In the RR and open field, there was no significant difference in the motor performance between controls and mice suffering from mild MOG-EAE. Yet EAE mice displayed an increased anxiety-like behavior with a 23% reduction of the time spent in the bright compartment of the LD Box as well as an increased SR. In the LH paradigm, mice suffering from MOG-EAE were twice as much prone to depressive-like behavior. These changes correlate with an increase of hippocampal tissue tumor necrosis factor alpha levels and neuronal loss in the hippocampus. Modulation of monoaminergic transmission by chronic application of the antidepressant amitriptyline resulted in a decreased startle reaction and increased hippocampal norepinephrine levels. These data imply that chronic inflammation in the CNS may impact on emotional responses in rodent models of anxiety.
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ABSTRACT: Experimental autoimmune encephalomyelitis (EAE) is a well-established animal model of multiple sclerosis. This study aimed to investigate the protective and therapeutic effects of Nigella sativa (N. sativa) seeds (2.8 g/kg body weight) in EAE-induced rats. EAE-induced animals were divided into: (1) EAE-induced animals (“EAE” group). (2) “N. sativa + EAE” group received a daily oral administration of N. sativa 2 weeks prior to EAE induction until the end of the experiment. (3) “EAE + N. sativa” group received a daily oral administration of N. sativa after the appearance of the first clinical signs until the end of the experiment. All animals were sacrificed at the 28th day post EAE-induction. Disease pathogenesis was monitored using a daily clinical scoring, body weight, open field test, histopathological and ultrastructural examination and determination of some oxidative stress parameters in the cortex and hippocampus. N. sativa ameliorated the clinical signs and suppressed inflammation observed in EAE-induced rats. In addition, N. sativa enhanced remyelination in the hippocampus. However, protection of rats with N. sativa administered 2 weeks prior to EAE induction and its continuation until the end of the experiment resulted in a significant increase in the cortical lipid peroxide level with reference to control and “EAE” rats. In conclusion, N. sativa seeds could be used as a protective agent or an adjunct treatment for EAE even when the treatment started after the appearance of the first clinical signs. However, the dose and duration of N. sativa must be taken into consideration to avoid its probable pro-oxidant effect.09/2014; 67(5). DOI:10.1016/j.jobaz.2014.08.005
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ABSTRACT: Depression-be it a formal diagnosis based on consensus clinical criteria, or a collection of symptoms revealed by a self-report rating scale-is common in patients with multiple sclerosis (MS) and adds substantially to the morbidity and mortality associated with this disease. This Review discusses the prevalence and epidemiology of depression in patients with MS, before covering aetiological factors, including genetics, brain pathology, immunological changes, dysregulation of the hypothalamic-pituitary-adrenal axis, and psychosocial influences. Treatment options such as antidepressant drugs, cognitive-behavioural therapy, mindfulness-based therapy, exercise and electroconvulsive therapy are also reviewed in the context of MS-related depression. Frequent comorbid conditions, namely pain, fatigue, anxiety, cognitive dysfunction and alcohol use, are also summarized. The article then explores three key challenges facing researchers and clinicians: what is the optimal way to define depression in the context of diseases such as MS, in which the psychiatric and neurological symptoms overlap; how can current knowledge about the biological and psychological underpinnings of MS-related depression be used to boost the validity of this construct; and can intervention be made more effective through use of combination therapies with additive or synergistic effects, which might exceed the modest benefits derived from their individual components?Nature Reviews Neurology 08/2014; 10(9). DOI:10.1038/nrneurol.2014.139 · 14.10 Impact Factor
Edited by Ellie O'Connor, 02/2015; Saarbrücken: Scholars' Press., ISBN: 978-3-639-76182-5