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Dive into the research topics where L. Trevor Young is active.

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Featured researches published by L. Trevor Young.


Bipolar Disorders | 2009

Canadian Network for Mood and Anxiety Treatments (CANMAT) and International Society for Bipolar Disorders (ISBD) collaborative update of CANMAT guidelines for the management of patients with bipolar disorder: update 2009

Lakshmi N. Yatham; Sidney H. Kennedy; Sagar V. Parikh; Ayal Schaffer; Serge Beaulieu; Martin Alda; Claire O'Donovan; Glenda MacQueen; Roger S. McIntyre; Verinder Sharma; Arun V. Ravindran; L. Trevor Young; Roumen Milev; David J. Bond; Benicio N. Frey; Benjamin I. Goldstein; Beny Lafer; Boris Birmaher; Kyooseob Ha; Willem A. Nolen; Michael Berk

The Canadian Network for Mood and Anxiety Treatments published guidelines for the management of bipolar disorder in 2005, with updates in 2007 and 2009. This third update, in conjunction with the International Society for Bipolar Disorders, reviews new evidence and is designed to be used in conjunction with the previous publications.The recommendations for the management of acute mania remain largely unchanged. Lithium, valproate, and several atypical antipsychotic agents continue to be first-line treatments for acute mania. Monotherapy with asenapine, paliperidone extended release (ER), and divalproex ER, as well as adjunctive asenapine, have been added as first-line options.For the management of bipolar depression, lithium, lamotrigine, and quetiapine monotherapy, as well as olanzapine plus selective serotonin reuptake inhibitor (SSRI), and lithium or divalproex plus SSRI/bupropion remain first-line options. Lurasidone monotherapy and the combination of lurasidone or lamotrigine plus lithium or divalproex have been added as a second-line options. Ziprasidone alone or as adjunctive therapy, and adjunctive levetiracetam have been added as not-recommended options for the treatment of bipolar depression. Lithium, lamotrigine, valproate, olanzapine, quetiapine, aripiprazole, risperidone long-acting injection, and adjunctive ziprasidone continue to be first-line options for maintenance treatment of bipolar disorder. Asenapine alone or as adjunctive therapy have been added as third-line options.


Biological Psychiatry | 2001

Increased hippocampal bdnf immunoreactivity in subjects treated with antidepressant medication

Biao Chen; Dar Dowlatshahi; Glenda MacQueen; Jun-Feng Wang; L. Trevor Young

BACKGROUND The cAMP signaling pathway, and its downstream neurotrophic factor BDNF, are major targets of antidepressant medications. Abnormalities in this pathway have previously been reported in postmortem brain of subjects with mood disorders. This study was designed to test whether the diagnosis of a mood disorder, or treatment with an antidepressant or mood stabilizer was associated with changes in hippocampal BDNF in postmortem brain. METHODS Frozen postmortem anterior hippocampus sections were obtained from the Stanley Foundation Neuropathology Consortium. Tissue from subjects with major depression, bipolar disorder, schizophrenia and nonpsychiatric control subjects were stained for BDNF using immunohistochemistry. RESULTS Increased BDNF expression was found in dentate gyrus, hilus and supragranular regions in subjects treated with antidepressant medications at the time of death, compared with antidepressant-untreated subjects. Furthermore, there was a trend toward increased BDNF expression in hilar and supragranular regions in depressed subjects treated with antidepressants, compared with the subjects not on these medications at the time of death. CONCLUSIONS These findings are consistent with recent studies measuring CREB levels in this same subject sample, and support current animal and cellular models of antidepressant function.


Proceedings of the National Academy of Sciences of the United States of America | 2003

Course of illness, hippocampal function, and hippocampal volume in major depression

Glenda MacQueen; Stephanie Campbell; Bruce S. McEwen; Kathryn Macdonald; Shigeko Amano; Russell T. Joffe; Claude Nahmias; L. Trevor Young

Studies have examined hippocampal function and volume in depressed subjects, but none have systematically compared never-treated first-episode patients with those who have had multiple episodes. We sought to compare hippocampal function, as assessed by performance on hippocampal-dependent recollection memory tests, and hippocampal volumes, as measured in a 1.5-T magnetic resonance imager, in depressed subjects experiencing a postpubertal onset of depression. Twenty never-treated depressed subjects in a first episode of depression were compared with matched healthy control subjects. Seventeen depressed subjects with multiple past episodes of depression were also compared with matched healthy controls and to the first-episode patients. Both first- and multiple-episode depressed groups had hippocampal dysfunction apparent on several tests of recollection memory; only depressed subjects with multiple depressive episodes had hippocampal volume reductions. Curve-fitting analysis revealed a significant logarithmic association between illness duration and hippocampal volume. Reductions in hippocampal volume may not antedate illness onset, but volume may decrease at the greatest rate in the early years after illness onset.


Journal of Affective Disorders | 2008

Oxidative stress markers in bipolar disorder: A meta-analysis

Ana Cristina Andreazza; Márcia Kauer-Sant'Anna; Benicio N. Frey; David J. Bond; Flávio Kapczinski; L. Trevor Young; Lakshmi N. Yatham

BACKGROUND Oxidative stress is thought to mediate neuropathological processes of a number of neuropsychiatric disorders and recent data suggest that oxidative stress may be involved in the pathophysiology of bipolar disorder (BD). In the present investigation, we conducted a meta-analysis of studies that evaluated markers of oxidative stress in individuals with BD, as compared to healthy controls. METHODS A Medline search was conducted to identify studies that measured peripheral markers of oxidative stress in bipolar disorder. Data were subjected to meta-analysis using a random effects model to examine the effect sizes of the pooled results. Bias assessment (Eggers test) and assessment of heterogeneity (I(2)) were also carried out. RESULTS Thiobarbituric acidic reactive substances (TBARS) (p = 0.001) as well as NO activity (p = 0.02) were significantly increased in BD with a large effect size for TBARS and a moderate effect size for increase in NO. No significant effect sizes were observed for the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase (all p>0.05). LIMITATIONS Some caution is warranted in interpreting these results: (1) Eggers test was positive for SOD, suggesting that SOD results may have been influenced by a publication bias. (2) We analyzed the absolute values of each antioxidant enzyme separately and the literature suggests that an imbalance between the antioxidant enzymes is a better indication of the presence of oxidative stress. CONCLUSIONS The present meta-analysis suggests that oxidative stress markers are increased in BD and that oxidative stress may play a role in the pathophysiology of BD.


The International Journal of Neuropsychopharmacology | 2011

Decreased levels of glutathione, the major brain antioxidant, in post-mortem prefrontal cortex from patients with psychiatric disorders

Jeremy W. Gawryluk; Jun-Feng Wang; Ana Cristina Andreazza; Li Shao; L. Trevor Young

Accruing data suggest that oxidative stress may be a factor underlying the pathophysiology of bipolar disorder (BD), major depressive disorder (MDD), and schizophrenia (SCZ). Glutathione (GSH) is the major free radical scavenger in the brain. Diminished GSH levels elevate cellular vulnerability towards oxidative stress; characterized by accumulating reactive oxygen species. The aim of this study was to determine if mood disorders and SCZ are associated with abnormal GSH and its functionally related enzymes. Post-mortem prefrontal cortex from patients with BD, MDD, SCZ, and from non-psychiatric comparison controls were provided by the Stanley Foundation Neuropathology Consortium. Spectrophotometric analysis was utilized for the quantitative determination of GSH, while immunoblotting analyses were used to examine expression of glutamyl-cysteine ligase (GCL), GSH reductase (GR), and GSH peroxidase (GPx). We found that the levels of reduced, oxidized, and total GSH were significantly decreased in all psychiatric conditions compared to the control group. Although GCL and GR levels did not differ between groups, the levels of GPx were reduced in MDD and SCZ compared to control subjects. Since oxidative damage has been demonstrated in MDD, BD, and SCZ, our finding that GSH levels are reduced in post-mortem prefrontal cortex suggests that these patient groups may be more susceptible to oxidative stress.


The International Journal of Neuropsychopharmacology | 2009

Brain-derived neurotrophic factor and inflammatory markers in patients with early- vs. late-stage bipolar disorder

Márcia Kauer-Sant'Anna; Flávio Kapczinski; Ana Cristina Andreazza; David J. Bond; Raymond W. Lam; L. Trevor Young; Lakshmi N. Yatham

Bipolar I disorder (BD) has a poorer longer-term outcome than previously thought, with persistent cognitive impairment and functional decline. The neurobiological underpinnings that might underlie these changes remain unknown. Changes in brain-derived neurotrophic factor (BDNF) levels and cytokines are potential candidates. The aim of this study was to examine both cytokine and BDNF levels and their relationship in BD patients in the early and late stages of the disorder. We measured serum BDNF, TNF-alpha, IL-6 and IL-10 levels in a total of 60 patients with BD I and we compared those in early stages of illness with those in late stages of illness and also compared both groups with 60 matched healthy controls. BDNF was decreased only in those patients in the late stage of bipolar disorder. Moreover, BDNF levels were negatively correlated with length of illness. In contrast, all interleukins and TNF-alpha were increased in the early stages of BD, compared to controls. While TNF-alpha and IL-6 continued to be significantly higher than controls at late stages of BD, IL-10 did not. When levels were compared between patients at early and late stages of illness, there was a significant decrease in BDNF and IL-6 in the later stage of BD compared to the early stage. Inversely, TNF-alpha showed a significant increase at the later stage. Failure of inflammatory defences in the late stage of the disorder may account for reduction in BDNF and continued elevations in cytokines; thus these may have the potential to serve as markers of illness progression in BD.


Acta Psychiatrica Scandinavica | 2001

A review of psychosocial outcome in patients with bipolar disorder

Glenda MacQueen; L. Trevor Young; Russell T. Joffe

Objective: The aim of this paper is to review outcome in patients with bipolar disorder as assessed by interepisode level of functioning, as until recently this dimension of outcome has been relatively under‐emphasized.


Archives of General Psychiatry | 2010

Mitochondrial Complex I Activity and Oxidative Damage to Mitochondrial Proteins in the Prefrontal Cortex of Patients With Bipolar Disorder

Ana C. Andreazza; Li Shao; Jun-Feng Wang; L. Trevor Young

CONTEXT Accumulating evidence suggests that mitochondrial dysfunction and oxidative stress contribute to the pathogenesis of bipolar disorder and schizophrenia. It remains unclear whether mitochondrial dysfunction, specifically complex I impairment, is associated with increased oxidative damage and, if so, whether this relationship is specific to bipolar disorder. OBJECTIVE To evaluate whether decreased levels of the electron transport chain complex I subunit NDUFS7 are associated with complex I activity and increased oxidative damage to mitochondrial proteins in the prefrontal cortex of patients with bipolar disorder, schizophrenia, or major depressive disorder. DESIGN Postmortem prefrontal cortex from patients and controls were assessed using immunoblotting, spectrophotometric, competitive enzyme immunoassay to identify group differences in expression and activity of complex I, and in oxidative damage in mitochondria. SETTING University of British Columbia, Vancouver, Canada. Patients Forty-five patients with a psychiatric disorder (15 each with bipolar disorder, schizophrenia, and major depressive disorder) and 15 nonpsychiatric control subjects were studied. MAIN OUTCOME MEASURES Oxidative damage to proteins and mitochondrial complex I activity. RESULTS Levels of NDUFS7 and complex I activity were decreased significantly in patients with bipolar disorder but were unchanged in those with depression and schizophrenia compared with controls. Protein oxidation, as measured by protein carbonylation, was increased significantly in the bipolar group but not in the depressed or schizophrenic groups compared with controls. We observed increased levels of 3-nitrotyrosine in the bipolar disorder and schizophrenia groups. CONCLUSIONS Impairment of complex I may be associated with increased protein oxidation and nitration in the prefrontal cortex of patients with bipolar disorder. Therefore, complex I activity and mitochondrial dysfunction may be potential therapeutic targets for bipolar disorder.


The Lancet | 1998

Increased temporal cortex CREB concentrations and antidepressant treatment in major depression

L. Trevor Young; Dar Dowlatshahi; Glenda MacQueen; Jun-Feng Wang

There was no correlation between temporal cortex CREB concentration and age (r =0·046, p=0·73) or postmortem interval (r = 0·039, p=0·77). In the MDD group, higher temporal cortex CREB concentrations were found in patients treated with antidepressants at the time of death (figure) than in untreated patients (p=0·01). Furthermore, MDD patients not on antidepressants at the time of death had lower CREB concentrations than controls (p=0·02), whereas treated patients did not differ from the control group (p=0·17). There were no differences in the occipital cortex, which suggests that the effects of antidepressants may be regional. There were no differences in CREB concentrations between patients with bipolar disorder or schizophrenia and controls or between treated and untreated patients with bipolar disorder and schizophrenia, which suggests that this drug effect may be specific to MDD. Downstream changes in the cAMP pathway may occur in patients with MDD and antidepressant treatment may be associated with a return to normal temporal cortex of CREB in patients with MDD. The cAMP pathway might ultimately be one of many intracellular pathways contributing to the pathophysiology of depression and its


Bipolar Disorders | 2009

Increased oxidative stress in the anterior cingulate cortex of subjects with bipolar disorder and schizophrenia.

Jun-Feng Wang; Li Shao; Xiujun Sun; L. Trevor Young

BACKGROUND Recent studies indicate the presence of mitochondrial dysfunction in brains of subjects with bipolar disorder (BD). Because the mitochondrial electron transport chain is a major source for production of reactive oxygen species that cause oxidative stress, we sought to determine in the present study if BD is associated with oxidative stress. METHODS Postmortem anterior cingulate brain sections from subjects with BD, major depressive disorder (MDD), or schizophrenia, and from nonpsychiatric, non-neurologic comparison controls were generously provided by the Stanley Foundation Neuropathology Consortium. Oxidative stress was determined by analyzing 4-hydroxynonenal (4-HNE), a major product of lipid peroxidation. The level of 4-HNE was determined by measuring 4-HNE protein adducts using immunohistochemistry. RESULTS We found that 4-HNE levels were significantly increased by 59% in BD subjects and by 47% in schizophrenia subjects, but not in MDD subjects, when compared with controls. Levels of 4-HNE were negatively correlated with pH in all 60 subjects. When pH was used as covariate, 4-HNE levels were still significantly increased in BD subjects when compared with controls. Further, 4-HNE levels were significantly correlated with pH values only in BD subjects, but not in MDD, schizophrenia, or control subjects. CONCLUSIONS Oxidative damage in the brain may contribute in part to the pathological process in BD and schizophrenia. This finding also suggests antioxidative stress as a probable alternative approach to the pharmacological treatment of these psychiatric disorders.

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Jun-Feng Wang

University of British Columbia

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Lakshmi N. Yatham

University of British Columbia

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Jerry J. Warsh

Centre for Addiction and Mental Health

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