Rodrigo B. Mansur

Novel therapeutic targets in depression: Minocycline as a candidate treatment

Mood disorders are marked by high rates of non-recovery, recurrence, and chronicity, which are insufficiently addressed by current therapies. Several patho-etiological models have been proposed that are not mutually exclusive and include but are not limited to the monoamine, inflammatory, neurotrophic, gliotrophic, excitatory, and oxidative stress systems. A derivative of these observations is that treatment(s) which target one or more of these mechanistic steps may be capable of mitigating, or preventing, disparate psychopathological features. Minocycline is an agent with pleiotropic properties that targets multiple proteins and cellular processes implicated in the patho-etiology of mood disorders. Moreover, preclinical and preliminary clinical evidence suggests that minocycline possesses antidepressant properties. Herein, we provide the rationale for conducting a randomized, controlled trial to test the antidepressant properties of minocycline.

Towards a multifactorial approach for prediction of bipolar disorder in at risk populations

BACKGROUND The high prevalence, recurrence rate, chronicity, and illness burden in bipolar disorder (BD) are well documented. Moreover, insufficient response with conventional pharmacological and manual-based psychosocial interventions, as well as evidence of illness progression and acceleration, invite the need for early detection and primary prevention. METHODS Herein we comprehensively review extant studies reporting on a bipolar prodrome. The overarching aim is to propose a predictive algorithm (i.e. prediction of BD in at-risk populations) integrating genetic (i.e. family history), environmental (e.g. childhood maltreatment) and biological markers (i.e. BDNF, inflammatory and oxidative stress markers). Computerized databases i.e. Pubmed, PsychInfo, Cochrane Library and Scielo were searched using the followed terms: bipolar disorder cross-referenced with prodromal, preclinical, at risk mental states, clinical high risk, ultra high risk, biomarkers, brain-derived neurotrophic factor, inflammation, cytokines, oxidative stress, prediction and predictive model. RESULTS Available evidence indicates that a prodrome to bipolar disorder exists. Commonly encountered features preceding the onset of a manic episode are affective lability, irritability, anger, depression, anxiety, substance use disorders, sleep disorders, as well as disturbances in attention and cognition. Non-specificity and insufficient sensitivity have hampered the development of an adequate prediction algorithm. LIMITATIONS Limitations include biases associated with retrospective studies, poor characterization of clinical high risk, inadequacy of prospective studies regarding sample selection and absence of specificity of risk states. CONCLUSION We propose a hypothetical prediction algorithm that is combinatorial in approach that attempts to integrate family history, early adversity, and selected biomarkers.

The role of oxidative and nitrosative stress in accelerated aging and major depressive disorder

Major depressive disorder (MDD) affects millions of individuals and is highly comorbid with many age associated diseases such as diabetes mellitus, immune-inflammatory dysregulation and cardiovascular diseases. Oxidative/nitrosative stress plays a fundamental role in aging, as well as in the pathogenesis of neurodegenerative/neuropsychiatric disorders including MDD. In this review, we critically review the evidence for an involvement of oxidative/nitrosative stress in acceleration of aging process in MDD. There are evidence of the association between MDD and changes in molecular mechanisms involved in aging. There is a significant association between telomere length, enzymatic antioxidant activities (SOD, CAT, GPx), glutathione (GSH), lipid peroxidation (MDA), nuclear factor κB, inflammatory cytokines with MDD. Major depression also is characterized by significantly lower concentration of antioxidants (zinc, coenzyme Q10, PON1). Since, aging and MDD share a common biological base in their pathophysiology, the potential therapeutic use of antioxidants and anti-aging molecules in MDD could be promising.

Anti-inflammatory agents in the treatment of bipolar depression: a systematic review and meta-analysis

Inflammation has been implicated in the risk, pathophysiology, and progression of mood disorders and, as such, has become a target of interest in the treatment of bipolar disorder (BD). Therefore, the objective of the current qualitative and quantitative review was to determine the overall antidepressant effect of adjunctive anti‐inflammatory agents in the treatment of bipolar depression.

Inflammation as a neurobiological substrate of cognitive impairment in bipolar disorder: Evidence, pathophysiology and treatment implications.

BACKGROUND Bipolar disorder (BD) has been associated with cognitive impairment during depressed, manic and euthymic periods. Inflammation has been shown to be involved in the pathophysiology of BD and cognitive impairment. METHODS For this systematic review, the MEDLINE/PubMed, Embase, Google Scholar and ClinicalTrials.gov databases were searched for relevant articles assessing the association between cognitive function and inflammatory markers in BD subjects. A discussion of potential mechanisms and therapeutic implications is also included to provide further context to the subject matter. RESULTS Eight studies, including a total of 555 BD subjects, assessing the association between cognitive function and inflammatory markers were identified. Cognitive dysfunction was associated with elevated levels of pro-inflammatory markers YKL40, IL-6, sCD40L, IL-1Ra, hsCRP and TNF-α. Mechanistically, elevation in inflammatory cytokines alters monoamine levels leading to cognitive and affective dysfunction. Neuro-inflammation, manifesting as microglial activation, leads to increased oxidative stress, pathologic synaptic pruning and impaired neuroplasticity in key brain regions sub-serving mood and cognition. Immune dysfunction also activates the hypothalamic-pituitary-adrenal (HPA) axis leading to hypercortisolemia and metabolic dysfunction, further promoting neuronal dysfunction. Anti-inflammatory agents are therefore currently being investigated in the treatment of BD and appear to exert an antidepressant effect; however, cognitive outcomes have yet to be reported. CONCLUSION Several studies suggest that immune dysfunction is associated with cognitive impairment in BD. Several neurobiological pathways have been identified whereby immune dysfunction may promote cognitive impairment in BD. Future investigations of anti-inflammatory agents targeting cognitive function as a treatment outcome are merited.

Cytokines in schizophrenia: possible role of anti-inflammatory medications in clinical and preclinical stages.

Aims:  In this paper, we review the literature on the efficacy of anti‐inflammatory agents as neuroprotectors in clinical and preclinical stages of schizophrenia.

Advancing biomarker research: utilizing ‘Big Data’ approaches for the characterization and prevention of bipolar disorder

To provide a strategic framework for the prevention of bipolar disorder (BD) that incorporates a ‘Big Data’ approach to risk assessment for BD.

The prevalence and illness characteristics of DSM-5-defined “mixed feature specifier” in adults with major depressive disorder and bipolar disorder: Results from the International Mood Disorders Collaborative Project

BACKGROUND A substantial proportion of individuals with mood disorders present with sub-syndromal hypo/manic features. The objective of this analysis was to evaluate the prevalence and illness characteristics of the Diagnostic and Statistical Manual Version-5 (DSM-5) - defined mixed features specifier (MFS) in adults with major depressive disorder (MDD) and bipolar disorder (BD). METHOD Data from participants who met criteria for a current mood episode as part of MDD (n=506) or BD (BD-I: n=216, BD-II: n=130) were included in this post-hoc analysis. All participants were enrolled in the International Mood Disorders Collaborative Project (IMDCP): a collaborative research platform at the Mood Disorders Psychopharmacology Unit, University of Toronto and the Cleveland Clinic, Cleveland, Ohio. Mixed features specifier was operationalized as a score ≥ 1 on 3 or more select items on the Young Mania Rating Scale (YMRS) or ≥ 1 on 3 select items of the Montgomery Åsberg Depression Rating Scale (MADRS) or Hamilton Depression Rating Scale (HAMD-17) during an index major depressive episode (MDE) or hypo/manic episode, respectively. RESULTS A total of 26.0% (n=149), 34.0% (n=65), and 33.8% (n=49) of individuals met criteria for MFS during an index MDE as part of MDD, BD-I and BD-II, respectively. Mixed features specifier during a hypo/manic episode was identified in 20.4% (n=52) and 5.1% (n=8) in BD-I and BD-II participants, respectively. Individuals with MDE-MFS as part of BD or MDD exhibited a more severe depressive phenotype (p=0.0002 and p<0.0002, respectively) and reported a higher rate of alcohol/substance use disorder in the context of BD but not MDD (p=0.002). Individuals with MFS were more likely to have co-existing heart disease suggestive of a distinct pattern of comorbidity and neurobiology. LIMITATIONS Data were post-hoc and obtained from individuals utilizing a university-based mood disorder centre which may affect generalizability. CONCLUSIONS Diagnostic and Statistical Manual Version-5-defined MFS is common during an MDE as part of MDD and BD. The presence of MFS identifies a subgroup of individuals with greater illness complexity and possibly a higher rate of cardiovascular comorbidity. The results herein underscore the common occurrence of MFS in adults with either BD or MDD. Moreover, the results of our analysis indicate that adults with mood disorders and MFS have distinct clinical characteristics and comorbidity patterns.

The Prevalence, Measurement, and Treatment of the Cognitive Dimension/Domain in Major Depressive Disorder

Insufficient outcomes amongst adults with major depressive disorder (MDD) provide the impetus to identify and refine therapeutic targets that are most critical to outcome from patient, provider, and societal perspectives. Towards this aim, a pivotal shift towards the transnosological domain, cognition, is occurring in the study of MDD and other brain disorders. This paper aims to provide a framework for conceptualizing and prioritizing cognitive function amongst adults with MDD with a particular view to provide a conceptual framework for research and clinical priorities. We also summarize extant data pertaining to psychotropic effects, notably antidepressants, on the cognitive dimension/domain. This narrative review was based on articles identified through a PubMed/MEDLINE search of all English-language articles published between January 1966 and October 2014. The search words were major depressive disorder, depression, unipolar depression, cognition, cognitive dysfunction, cognitive deficit, and cognitive function. The search was supplemented with a manual review of relevant references. The selection of articles for inclusion in this review was based on overall methodological quality as well as on their pertinence to informing the framework described herein. Cognitive dysfunction in MDD is a discrete domain subserved by discrete yet overlapping substrates. There is a need to provide a glossary of terms commonly employed in the cognition literature for consensus as to the appropriate screening, measurement, and monitoring tools. The guiding principle of measurement-based care should include systematic assessment and measurement of cognition in subpopulations with MDD, as a tactic to improve outcome. Relatively few treatment strategies have demonstrated efficacy specifically for the cognitive domain in MDD. The antidepressant vortioxetine has replicated evidence of specific pro-cognitive effects in adults with MDD across multiple subdomains of cognitive function. Vortioxetine is a novel antidepressant that is hypothesized to act through a combination of direct effects on receptor activity and serotonin receptor inhibition, as well as other systems. Pro-cognitive effects for other US FDA-approved agents are suggested, but pseudospecificity has not been excluded as a possible explanation of their beneficial effects on cognitive function. A disparate assortment of other agents are currently under investigation for possible benefit in mitigating cognitive deficits and improving cognitive performance (e.g., intranasal insulin, erythropoietin, anti-inflammatory agents). Non-pharmacological approaches including, but not limited to, cognitive remediation (CR), aerobic exercise, and neuromodulation are promising.

Peripheral interleukin-2 level is associated with negative symptoms and cognitive performance in schizophrenia.

Although several studies have pointed to a possible role of interleukin 2 (IL-2) in schizophrenia (SZ), association between IL-2 and the different groups of symptoms has not been explored. The objective of this study was to investigate a possible correlation of peripheral IL-2 levels with symptoms and cognitive performance in patients with SZ. In addition, we compared the plasma levels of IL-2 between patients with SZ and healthy controls. Twenty-nine chronically medicated outpatients with SZ according to DSM-IV were compared with twenty-six healthy controls. The patients were evaluated with the Positive and Negative Syndrome Scale (PANSS), the Calgary Depression Scale for Schizophrenia (CDSS), the Clinical Global Impression (CGI) and the Global Assessment of Functioning (GAF). All the participants had blood collected into EDTA tubes by venipuncture between 9:00 and 10:00AM. Plasma concentrations of IL-2 were determined by cytometric bead array. A computerized neuropsychological battery assessed verbal learning, verbal fluency, working memory, set shifting, executive function, inhibition and intelligence. Patients with SZ had lower levels of IL-2 than healthy controls (p<0.001). In the SZ group, IL-2 levels were positively correlated with scores in the digit span test (rho=0.416, P=0.025) and intelligence (rho=0.464, P=0.011). We also found a negative correlation between IL-2 and total score in the negative subscale of PANSS (rho=-0.447, p=0.015). Our findings suggest that IL-2 may be involved in the mechanisms related to cognitive deterioration and negative symptomatology in schizophrenia.