The microRNA network is altered in anterior cingulate cortex of patients with unipolar and bipolar depression
Introduction
Known as melancholia at the time of Hippocrates, ‘depression’ is a general term that encompasses a large number of mood disorders. Two of these particularly debilitating disorders—major depressive disorder (MDD, or unipolar depression) and bipolar disorder (BP; bipolar depression)—are also extremely common, with a lifetime prevalence of 16.6% and 3.9%, respectively (Kessler et al., 2005). Though a genetic component has been established (due in part to a high degree of heritability (Bierut et al., 1999, Burton et al., 2007, Lohoff, 2010, McGuffin et al., 2003, Sklar et al., 2011, Smoller and Finn, 2003)), the genomic architecture of these disorders remains poorly understood.
In recent years, however, microRNAs (miRNAs)—small, 21–23 nt RNAs that canonically act as post-transcriptional regulators of gene expression—have become an increasing focus for understanding CNS processes. Greater than 40% of all protein-coding transcripts are predicted to be regulated by miRNAs (Tan et al., 2009, Xie et al., 2005). MiRNAs are also highly enriched within the CNS, with greater than two-thirds of identified miRNAs expressed in brain (Bak et al., 2008, Cao et al., 2006, Sempere et al., 2004). MiRNAs are also key governors of CNS processes at both the cellular level (e.g. synaptic plasticity, neuronal differentiation and neuronal migration (Cui et al., 2012, Makeyev et al., 2007, Morgado et al., 2014, Schratt et al., 2006)) and the systems level, with miRNAs linked to the regulation of HPA axis glucocorticoid negative feedback and complex behaviors such as responses to both acute and chronic stress as well as mood and anxiety (Bahi et al., 2014, Haramati et al., 2011, Honda et al., 2013, Katsuura et al., 2012, Muinos-Gimeno et al., 2011, Vreugdenhil et al., 2009).
The role of miRNAs in the regulation of stress responses is of particular interest given that chronic stress is not only a precipitant of mood and affective disorders (Breslau and Davis, 1986, Ilgen and Hutchison, 2005) but HPA axis disruption is one of the most commonly observed pathophysiologies in MDD patients, with symptomatic severity correlating with extent of hypercortisolemia (Gibbons and Mc, 1962, Vythilingam et al., 2004). Intriguingly, a number of studies have directly demonstrated dysregulation of the miRNA regulatory network in patients with a variety of mood and affective disorders, with the vast majority focusing on schizophrenia (SZ) (Beveridge et al., 2010, Beveridge et al., 2008, Kim et al., 2010, Miller et al., 2012, Moreau et al., 2011, Perkins et al., 2007, Santarelli et al., 2011, Shi et al., 2012, Smalheiser et al., 2014, Wan et al., 2015). Absent from these studies, however, has been analysis of the anterior cingulate cortex (AnCg), a brain region centrally involved in the regulation of mood, affect and cognition (Drevets et al., 2008, Ebert and Ebmeier, 1996, Mayberg et al., 1999, Posner and DiGirolamo, 1998). Alterations in AnCg function have been increasingly linked to mood disorders with AnCg activity previously demonstrated to differentiate patients with unipolar versus bipolar depression (Diler et al., 2014) and also to predict successful pharmaceutical and cognitive treatment response (Fujino et al., 2015, Mulert et al., 2007, Pizzagalli et al., 2001, Salvadore et al., 2009). Further work has also established alterations in various systems within AnCg in MDD and BP disorders, including dysregulation in the fibroblast growth factor (FGF) system and clock genes (Bunney et al., 2015, Cheng et al., 2007, Evans et al., 2004).
In the present study we assessed miRNA expression in the AnCg of both MDD and BP patients compared to controls. As miRNAs exert their regulatory effects by targeting mRNA transcripts, we employed bioinformatics approaches to identify mRNA targets of miRNAs whose expression varied due to disease and validated several mRNAs as direct targets. Finally, we examined the steady-state levels of a subset of validated mRNA targets and identified two that vary as a function of affective disease.
Section snippets
Postmortem brain tissue and RNA extraction
RNA samples derived from human post-mortem AnCg tissue were provided by the Pritzker Neuropsychiatric Research Consortium. The initial acquisition of tissue, microdissection of AnCg and subsequent RNA extraction that generated these samples is described in detail in (Evans et al., 2003). Briefly, brains were extracted during autopsy and sliced into coronal slabs approximately 0.75 cm thick. Slabs were then snap-frozen and stored at −80° C until subsequent dissections. Anterior cingulate cortex
Differential expression of a subset of miRNAs in AnCg of patients with MDD or BP disorder
Following qPCR detection 3 miRNAs—miR-33a, miR-144 and miR-431*—were excluded from analysis due to high variability among technical replicates and cycle threshold values > 30. After exclusion, 26 miRNAs were examined for differential expression in BP and MDD cohorts versus controls. Of these, 5 miRNAs—miR-132, miR-133a and miR-212 in the BP cohort; miR-184 in the MDD cohort, and miR-34a shared between cohorts—exhibited raw p-values < 0.05 (Fig. 1) (although none passed multiple correction
Discussion
Given their enrichment in the brain, their regulation of key CNS processes, their widespread regulation of protein-coding transcripts and their dysregulation in a number of illnesses, miRNAs are uniquely positioned to play a key role in the pathology of psychiatric illness. In this study we examined the expression of 26 miRNAs in the AnCg of MDD and BP patients versus controls. From this, we identified 5 miRNAs—3 in BP, 1 in MDD and 1 shared across both cohorts—that were differentially
Role of contributors
Joshua A Azevedo: study design, data analysis, manuscript drafting and final revision of manuscript.
Bradley S Carter: early-stage technical feasibility, final revision of manuscript.
Fan Meng: bioinformatics analysis, final revision of manuscript.
David L Turner: bioinformatics analysis, final revision of manuscript.
Manhong Dai: bioinformatics analysis, final revision of manuscript.
Alan F Schatzberg: overall study design and post-mortem sample procurement, final revision of manuscript.
Jack D
Role of the funding sources
This work was supported by NIH Grant R21 MH083175 (RCT). J. Azevedo was supported by NIH T-32-NS076401. This work was also funded by the Pritzker Neuropsychiatric Disorders Research Consortium, which is supported by the Pritzker Neuropsychiatric Disorders Research Fund L.L.C. A shared intellectual property agreement exists between this philanthropic fund and the University of Michigan, Stanford University, the Weill Medical College of Cornell University, the University of California at Irvine,
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Acknowledgement
This work was supported by NIH Grant R21 MH083175 (RCT). J. Azevedo was supported by NIH T-32-NS076401. This work was also funded by the Pritzker Neuropsychiatric Disorders Research Consortium, which is supported by the Pritzker Neuropsychiatric Disorders Research Fund L.L.C. A shared intellectual property agreement exists between this philanthropic fund and the University of Michigan, Stanford University, the Weill Medical College of Cornell University, the University of California at Irvine,
References (95)
- et al.
Altered sirtuin deacetylase gene expression in patients with a mood disorder
J. Psychiatr. Res.
(2011) - et al.
HPA axis and cytokines dysregulation in schizophrenia: potential implications for the antipsychotic treatment
Eur. Neuropsychopharmacol.
(1999) - et al.
Selective lentiviral-mediated suppression of microRNA124a in the hippocampus evokes antidepressants-like effects in rats
Psychoneuroendocrinology
(2014) - et al.
DISC1, PDE4B, and NDE1 at the centrosome and synapse
Biochem. Biophys. Res. Commun.
(2008) - et al.
microRNA modulation of circadian-clock period and entrainment
Neuron
(2007) - et al.
Hypothalamic-pituitary-adrenal axis and bipolar disorder
Psychiatr. Clin. North Am.
(2005) - et al.
The role of the cingulate gyrus in depression: from functional anatomy to neurochemistry
Biol. Psychiatry
(1996) - et al.
DNA microarray analysis of functionally discrete human brain regions reveals divergent transcriptional profiles
Neurobiol. Dis.
(2003) - et al.
Differential expression of microRNA in peripheral blood mononuclear cells as specific biomarker for major depressive disorder patients
J. Psychiatr. Res.
(2014) - et al.
PDE4B polymorphisms and decreased PDE4B expression are associated with schizophrenia
Schizophr. Res.
(2008)
Anterior cingulate volume predicts response to cognitive behavioral therapy in major depressive disorder
J. Affect Disord.
Plasma cortisol in depressive illness
J. Psychiatr. Res.
A history of major depressive disorder and the response to stress
J. Affect Disord.
MicroRNAs miR-144/144* and miR-16 in peripheral blood are potential biomarkers for naturalistic stress in healthy Japanese medical students
Neurosci. Lett.
MicroRNA expression profiling in the prefrontal cortex of individuals affected with schizophrenia and bipolar disorders
Schizophr. Res.
Conserved seed pairing, often flanked by adenosines, indicates that thousands of human genes are microRNA targets
Cell
Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) Method
Methods
The MicroRNA miR-124 promotes neuronal differentiation by triggering brain-specific alternative pre-mRNA splicing
Mol. Cell.
Altered microRNA expression profiles in postmortem brain samples from individuals with schizophrenia and bipolar disorder
Biol. Psychiatry
Human microRNAs miR-22, miR-138-2, miR-148a, and miR-488 are associated with panic disorder and regulate several anxiety candidate genes and related pathways
Biol. Psychiatry
Aberrant stress hormone receptor balance in the human prefrontal cortex and hypothalamic paraventricular nucleus of depressed patients
Psychoneuroendocrinology
Mice deficient for wild-type p53-induced phosphatase 1 display elevated anxiety- and depression-like behaviors
Neuroscience
Increased anterior cingulate cortical activity in response to fearful faces: a neurophysiological biomarker that predicts rapid antidepressant response to ketamine
Biol. Psychiatry
Upregulation of dicer and microRNA expression in the dorsolateral prefrontal cortex Brodmann area 46 in schizophrenia
Biol. Psychiatry
Aberrant expression of serum miRNAs in schizophrenia
J. Psychiatr. Res.
Haplotype analysis of single nucleotide polymorphisms in the vascular endothelial growth factor (VEGFA) gene and antidepressant treatment response in major depressive disorder
Psychiatry Res.
Hippocampal volume, memory, and cortisol status in major depressive disorder: effects of treatment
Biol. Psychiatry
Preliminary investigation of miRNA expression in individuals at high familial risk of bipolar disorder
J. Psychiatr. Res.
MicroRNA miR-124 regulates neurite outgrowth during neuronal differentiation
Exp. Cell Res.
Phosphodiesterase 4 inhibitors enhance sexual pleasure-seeking activity in rodents
Pharmacol. Biochem. Behav.
MicroRNA expression in the adult mouse central nervous system
RNA
Dysregulation of miR-34a links neuronal development to genetic risk factors for bipolar disorder
Mol. Psychiatry
Controlling the False Discovery Rate: A Practical and Powerful Approach to Multiple Testing
J Royal Stat. Soc. Series B
Vascular endothelial growth factor A gene expression level is higher in patients with major depressive disorder and not affected by cigarette smoking, hyperlipidemia or treatment with statins
Acta Neurobiol. Exp. (Wars)
Evidence for shared susceptibility in bipolar disorder and schizophrenia
Am. J. Med. Genet. C Semin. Med. Genet.
Comprehensive modeling of microRNA targets predicts functional non-conserved and non-canonical sites
Genome Biol.
Schizophrenia is associated with an increase in cortical microRNA biogenesis
Mol. Psychiatry
Dysregulation of miRNA 181b in the temporal cortex in schizophrenia
Hum. Mol. Genet.
Major depressive disorder in a community-based twin sample: are there different genetic and environmental contributions for men and women?
Arch. Gen. Psychiatry
Chronic stress and major depression
Arch. Gen. Psychiatry
Argonaute protein identity and pairing geometry determine cooperativity in mammalian RNA silencing
RNA
Circadian dysregulation of clock genes: clues to rapid treatments in major depressive disorder
Mol. Psychiatry
Genome-wide association study of 14,000 cases of seven common diseases and 3,000 shared controls
Nature
Noncoding RNAs in the mammalian central nervous system
Annu. Rev. Neurosci.
MiR-125b orchestrates cell proliferation, differentiation and migration in neural stem/progenitor cells by targeting nestin
BMC Neurosci.
Differential anterior cingulate activity during response inhibition in depressed adolescents with bipolar and unipolar major depressive disorder
J. Can. Acad. Child. Adolesc. Psychiatry
The subgenual anterior cingulate cortex in mood disorders
CNS Spectr.
Cited by (61)
The role of ncRNAs in depression
2024, HeliyonExploring the relationship between red blood cell levels and emotional regulation through the miR191-Riok3-Mxi1 pathway
2024, Journal of Traditional Chinese Medical SciencesPosttraumatic stress disorder, major depressive disorder, and noncoding RNAs
2022, Epigenetics of Stress and Stress Disorders