Disturbance of the Glutamatergic System in Mood Disorders

The role of glutamatergic system in the neurobiology of mood disorders draws increasing attention, as disturbance of this system is consistently implicated in mood disorders including major depressive disorder and bipolar disorder. Thus, the glutamate hypothesis of mood disorders is expected to complement and improve the prevailing monoamine hypothesis, and may indicate novel therapeutic targets. Since the contribution of astrocytes is found to be crucial not only in the modulation of the glutamatergic system but also in the maintenance of brain energy metabolism, alterations in the astrocytic function and neuroenergetic environment are suggested as the potential neurobiological underpinnings of mood disorders. In the present review, the evidence of glutamatergic abnormalities in mood disorders based on postmortem and magnetic resonance spectroscopy (MRS) studies is presented, and disrupted energy metabolism involving astrocytic dysfunction is proposed as the underlying mechanism linking altered energy metabolism, perturbations in the glutamatergic system, and pathogenesis of mood disorders.

Neurocognitive Changes and Their Neural Correlates in Patients with Type 2 Diabetes Mellitus

As the prevalence and life expectancy of type 2 diabetes mellitus (T2DM) continue to increase, the importance of effective detection and intervention for the complications of T2DM, especially neurocognitive complications including cognitive dysfunction and dementia, is receiving greater attention. T2DM is thought to influence cognitive function through an as yet unclear mechanism that involves multiple factors such as hyperglycemia, hypoglycemia, and vascular disease. Recent developments in neuroimaging methods have led to the identification of potential neural correlates of T2DM-related neurocognitive changes, which extend from structural to functional and metabolite alterations in the brain. The evidence indicates various changes in the T2DM brain, including global and regional atrophy, white matter hyperintensity, altered functional connectivity, and changes in neurometabolite levels. Continued neuroimaging research is expected to further elucidate the underpinnings of cognitive decline in T2DM and allow better diagnosis and treatment of the condition.

Prevalence and Associated Risk Factors of Psychological Distress in Patients with Gastric Cancer / 정신신체의학

OBJECTIVES: Though gastric cancer is one of the most common cancer in Korea, there have been few studies to explore psychological distress in gastric cancer. The purpose of this study was to investigate the prevalence and associated risk factors of psychological distress among patients with gastric cancer. METHODS: With consecutive sampling, a total of 274 patients with gastric cancer who admitted to a cancer center in a general hospital were recruited and assessed on psychological distress using the Hospital Anxiety and Depression Scale(HADS). Sociodemographic and cancer-related clinical variables were also evaluated. RESULTS: One hundred fifty-three(55.8%) patients with gastric cancer showed psychological distress. Logistic regression models revealed that having alcohol drinking experience[odds ratio(OR)=2.10, p=0,034] and low performance status(OR=2.40 p=0.002) were significantly associated with psychological distress in patients with gastric cancer. CONCLUSIONS: These findings indicate that approximately half of patients with gastric cancer suffered from psychological distress and having alcohol drinking experience and low performance status would be associated risk factors, suggesting the need for distress screening and psychosocial supportive care in patients with gastric cancer.

Contribution of Genetic and Neuroimaging Studies towards a Better Understanding of Post-Traumatic Stress Disorder

significant advances have been made in understanding the biological underpinnings of post-traumatic stress disorder(PTSD), particularly in the field of genetics and neuroimaging. Association studies in candidate genes related with hypothalamic-pituitary-adrenal axis, monoamines including serotonin, dopamine and noradrenaline, and proteins including FK506-binding protein 5 and brain-derived neurotrophic factor have provided important insights with regard to the vulnerability factors in PTSD. Genome-wide association studies and epigenetic studies may provide further information for the role of genes in the pathophysiology of PTSD. Hippocampus, medial prefrontal cortex, anterior cingulated cortex and amygdala have been considered as key structures that underlie PTSD pathophysiology. Future research that combines genetic and neuroimaging information may provide an opportunity for a more comprehensive understanding of PTSD.