GRIN2B Gene and Associated Brain Cortical White Matter Changes in Bipolar Disorder: A Preliminary Combined Platform Investigation
BIOMED RESEARCH INTERNATIONAL
Authors: Kuswanto, Carissa Nadia; Sum, Min Yi; Thng, Christopher Ren Zhi; Zhang, Yi Bin; Yang, Guo Liang; Nowinski, Wieslaw Lucjan; Sitoh, Yih Yian; Low, Chian Ming; Sim, Kang
Abstract
Abnormalities in glutamate signaling and glutamate toxicity are thought to be important in the pathophysiology of bipolar disorder (BD). Whilst previous studies have found brain white matter changes in BD, there is paucity of data about how glutamatergic genes affect brain white matter integrity in BD. Based on extant neuroimaging data, we hypothesized that GRIN2B risk allele is associated with reductions of brain white matter integrity in the frontal, parietal, temporal, and occipital regions and cingulate gyrus in BD. Fourteen patients with BD and 22 healthy controls matched in terms of age, gender and handedness were genotyped using blood samples and underwent diffusion tensor imaging. Compared to Gallele, brain FA values were significantly lower in BD patients with risk T allele in left frontal region (P = 0.001), right frontal region (P = 0.002), left parietal region (P = 0.001), left occipital region (P = 0.001), right occipital region (P < 0.001), and left cingulate gyrus (P = 0.001). Further elucidation of the interactions between different glutamate genes and their relationships with such structural, functional brain substrates will enhance our understanding of the link between dysregulated glutamatergic neurotransmission and neuroimaging endophenotypes in BD.
Long term transcriptional and behavioral effects in mice developmentally exposed to a mixture of endocrine disruptors associated with delayed human neurodevelopment
SCIENTIFIC REPORTS
Authors: Repouskou, Anastasia; Papadopoulou, Anastasia-Konstantina; Panagiotidou, Emily; Trichas, Panagiotis; Lindh, Christian; Bergman, Ake; Gennings, Chris; Bornehag, Carl-Gustaf; Ruegg, Joelle; Kitraki, Efthymia; Stamatakis, Antonios
Abstract
Accumulating evidence suggests that gestational exposure to endocrine disrupting chemicals (EDCs) may interfere with normal brain development and predispose for later dysfunctions. The current study focuses on the exposure impact of mixtures of EDCs that better mimics the real-life situation. We herein describe a mixture of phthalates, pesticides and bisphenol A (mixture N1) detected in pregnant women of the SELMA cohort and associated with language delay in their children. To study the long-term impact of developmental exposure to N1 on brain physiology and behavior we administered this mixture to mice throughout gestation at doses 0x, 0.5x, 10x, 100x and 500x the geometric mean of SELMA mothers' concentrations, and examined their offspring in adulthood. Mixture N1 exposure increased active coping during swimming stress in both sexes, increased locomotion and reduced social interaction in male progeny. The expression of corticosterone receptors, their regulator Fkbp5, corticotropin releasing hormone and its receptor, oxytocin and its receptor, estrogen receptor beta, serotonin receptors (Htr1a, Htr2a) and glutamate receptor subunit Grin2b, were modified in the limbic system of adult animals, in a region-specific, sexually-dimorphic and experience-dependent manner. Principal component analysis revealed gene clusters associated with the observed behavioral responses, mostly related to the stress axis. This integration of epidemiology-based data with an experimental model increases the evidence that prenatal exposure to EDC mixtures impacts later life brain functions.