Investigation of Blood-Brain Barrier Disruption in an Animal Model of Mania Induced by d-Amphetamine (original) (raw)

Effects of lithium on inflammatory and neurotrophic factors after an immune challenge in a lisdexamfetamine animal model of mania

Brazilian Journal of Psychiatry

Objective: To evaluate whether an animal model of mania induced by lisdexamfetamine dimesylate (LDX) has an inflammatory profile and whether immune activation by lipopolysaccharides (LPS) has a cumulative effect on subsequent stimuli in this model. We also evaluated the action of lithium (Li) on inflammatory and neurotrophic factors. Methods: Adult male Wistar rats were subjected to an animal model of mania. After the open-field test, they were given LPS to induce systemic immune activation. Subsequently, the animals' blood was collected, and their serum levels of brain-derived neurotrophic factor and inflammatory markers (tumor necrosis factor [TNF]-a, interleukin [IL]-6, IL-1b, IL-10, and inducible nitric oxide synthase [iNOS]) were measured. Results: LDX induced hyperactivity in the animals, but no inflammatory marker levels increased except brain-derived neurotrophic factor (BDNF). Li had no effect on serum BDNF levels but prevented iNOS levels from increasing in animals subjected to immune activation. Conclusion: Although Li prevented an LPS-induced increase in serum iNOS levels, its potential antiinflammatory effects in this animal model of mania were conflicting.

The underlying neurobiology of bipolar disorder

World psychiatry: official journal of the World Psychiatric Association (WPA)

Clinical studies over the past decades have attempted to uncover the biological factors mediating the pathophysiology of bipolar disorder (BD) utilizing a variety of biochemical and neuroendocrine strategies. Indeed, assessments of cerebrospinal fluid chemistry, neuroendocrine responses to pharmacological challenge, and neuroreceptor and transporter binding have demonstrated a number of abnormalities in the amine neurotransmitter systems in this disorder. However, recent studies have also implicated critical signal transduction pathways as being integral to the pathophysiology and treatment of BD, in addition to a growing body of data suggesting that impairments of neuroplasticity and cellular resilience may also underlie the pathophysiology of the disorder. It is thus noteworthy that mood stabilizers and antidepressants indirectly regulate a number of factors involved in cell survival pathways - including MAP kinases, CREB, BDNF and bcl-2 protein - and may thus bring about some of ...

Effects of lithium and valproate on amphetamine-induced oxidative stress generation in an animal model of mania

Journal of psychiatry & neuroscience : JPN, 2006

Previous studies have suggested that oxidative stress may play a role in the pathophysiology of bipolar disorder (BD). Moreover, recent studies indicate that lithium and valproate exert neuroprotective effects against oxidative stress. We studied the effects of the mood stabilizers lithium and valproate on amphetamine-induced oxidative stress in an animal model of mania. In the first model (reversal treatment), adult male Wistar rats received d-amphetamine or saline for 14 days, and between the 8th and 14th days, they were treated with lithium, valproate or saline. In the second model (prevention treatment), rats were pretreated with lithium, valproate or saline, and between the 8th and 14th days, they received d-amphetamine or saline. We assessed locomotor activity with the open-field task. We measured thiobarbituric acid reactive substances (TBARS) and protein carbonyl formation, as parameters of oxidative stress, and superoxide dismutase (SOD) and catalase (CAT), the major antiox...

Biological hypotheses and biomarkers of bipolar disorder

Psychiatry and Clinical Neurosciences, 2016

The most common mood disorders are major depressive disorders and bipolar disorders (BD). The pathophysiology of BD is complex, multifactorial, and not fully understood. Creation of new hypotheses in the field gives impetus for studies and for finding new biomarkers for BD. Conversely, new biomarkers facilitate not only diagnosis of a disorder and monitoring of biological effects of treatment, but also formulation of new hypotheses about the causes and pathophysiology of the BD. BD is characterized by multiple associations between disturbed brain development, neuroplasticity, and chronobiology, caused by: genetic and environmental factors; defects in apoptotic, immune-inflammatory, neurotransmitter, neurotrophin, and calcium-signaling pathways; oxidative and nitrosative stress; cellular bioenergetics; and membrane or vesicular transport. Current biological hypotheses of BD are summarized, including related pathophysiological processes and key biomarkers, which have been associated with changes in genetics, systems of neurotransmitter and neurotrophic factors, neuroinflammation, autoimmunity, cytokines, stress axis activity, chronobiology, oxidative stress, and mitochondrial dysfunctions. Here we also discuss the therapeutic hypotheses and mechanisms of the switch between depressive and manic state.

Neurobiology of bipolar disorders: a review of genetic components, signaling pathways, biochemical changes, and neuroimaging findings

Brazilian Journal of Psychiatry, 2020

Bipolar disorder (BD) is a chronic mental illness characterized by changes in mood that alternate between mania and hypomania or between depression and mixed states, often associated with functional impairment. Although effective pharmacological and non-pharmacological treatments are available, several patients with BD remain symptomatic. The advance in the understanding of the neurobiology underlying BD could help in the identification of new therapeutic targets as well as biomarkers for early detection, prognosis, and response to treatment in BD. In this review, we discuss genetic, epigenetic, molecular, physiological and neuroimaging findings associated with the neurobiology of BD. Despite the advances in the pathophysiological knowledge of BD, the diagnosis and management of the disease are still essentially clinical. Given the complexity of the brain and the close relationship between environmental exposure and brain function, initiatives that incorporate genetic, epigenetic, molecular, physiological, clinical, environmental data, and brain imaging are necessary to produce information that can be translated into prevention and better outcomes for patients with BD.

Medical Therapies for Mood Disorders Alter the Blood-Brain Barrier

Science, 1981

The effects of amitriptyline, lithium, and electroconvulsive shock on cerebral permeability and blood flow were tested. These three treatments share in common (i) the ability to influence the functional activity of central adrenergic neurons by way ofeffects on the release, reuptake, or metabolism ofnorepinephrine and (ii) therapeutic efficacy in mood disturbances. Under control conditions, cerebral permeability increases linearly with increasing arterial partial pressure of carbon dioxide and hence cerebral blood flow. All three treatments altered this relationship in a manner consistent with their adrenergic effects. Amitriptyline potentiated this increase in cerebral permeability whereas lithium and electroconvulsive shock blunted this phenomenon. These results support the hypothesis that one function of central adrenergic neurons is regulation of the blood-brain barrier and raise the possibility that a related effect may underlie the clinical usefulness of such treatments.

Differential expression profile between amygdala and blood during chronic lithium treatment in a rat model of depression – a pilot study

Acta Neurobiologiae Experimentalis

Lithium is a mood stabilizer widely used in the pharmacotherapy of bipolar disorder and treatment‑resistant depression. Taking into account dysregulated inflammatory activity in depression and the immunomodulatory role of lithium, we hypothesized that genes associated with inflammatory responses may be potential biomarkers of lithium action. We aimed to compare gene expression changes between the brain and the periphery after chronic lithium administration in an animal model of depression. Depressive behavior was induced by chronic mild stress protocol for 4 weeks. After 2 weeks, rats started to receive lithium (study group) or water (reference group). The control group were rats not exposed to stress. Amygdala, hippocampus, frontal cortex and peripheral blood were analyzed using whole transcriptome expression microarrays. Changes were confirmed with qPCR and ELISA assay. After 2 weeks of lithium administration, we observed significant changes in gene expression between amygdala and...

Signaling: cellular insights into the pathophysiology of bipolar disorder

Biological Psychiatry, 2000

Clinical studies over the years have provided evidence that monoamine signaling and hypothalamic-pituitaryadrenal axis disruption are integral to the pathophysiology of bipolar disorder. A full understanding of the pathophysiology from a molecular to a systems level must await the identification of the susceptibility and protective genes driving the underlying neurobiology of bipolar disorder. Furthermore, the complexity of the unique biology of this affective disorder, which includes the predisposition to episodic and often progressive mood disturbance, and the dynamic nature of compensatory processes in the brain, coupled with limitations in experimental design, have hindered our progress to date. Imaging studies in patient populations have provided evidence of a role for anterior cingulate, amygdala, and prefrontal cortex in the pathophysiology of bipolar disorder. More recent research strategies designed to uncover the molecular mechanisms underlying our pharmacologic treatments and their interaction in the regulation of signal transduction as well as more advanced brain imaging studies remain promising approaches. This experimental strategy provides data derived from the physiologic response of the system in affected individuals and addresses the critical dynamic interaction with pharmacologic agents that effectively modify the clinical expression of the pathophysiology.