Parahippocampal Atrophy is Associated with Depressive Symptoms in Alzheimer's Disease.

Background Alzheimer's disease (AD) patients frequently show depressive symptoms, yet the pathological background remains unclear. The voxel-based specific regional analysis system for AD (VSRAD) allows quantification of atrophy in the medial temporal structures. We measured the degree of parahippocampal atrophy in AD patients using VSRAD, and investigated the association between imaging analysis results and the severity of depressive symptoms. Methods Brain magnetic resonance imaging (MRI) was conducted in 39 AD outpatients, and all MRI data were analyzed using VSRAD. The target region of interest (ROI) mainly consisted of the parahippocampal gyrus. The degree of atrophy in the ROI was obtained from the averaged positive z score (Z-score) of the ROT. AD patients were divided into two groups based on the severity of their depressive symptoms using the Geriatric Depression Scale (GDS), the depressive group (D group: 20 patients) and non- depressive group (ND group: 19 patients), and the clinical characteristics and VSRAD results of both groups were compared. Results There were no significant differences in demographics or cognitive function between the two groups. The Z-scores of the D group were significantly higher than those of the ND group (p<0.05). Additionally, there was a significant positive correlation between the GDS score and Z-scores in the parahippocampal gyrus. Conclusions Our findings suggested that the severity of depressive symptoms is associated with the severity of parahippocampal atrophy in AD patients.

The Relationship Between Medial Temporal Lobe Atrophy and Cognitive Impairment in Patients With Dementia With Lewy Bodies.

BACKGROUND: The relationship between medial temporal lobe atrophy (MTA) and cognitive impairment in patients with dementia with Lewy bodies (DLB) remains unclear. We examined this relationship using voxel-based specific regional analysis system for Alzheimer disease (VSRAD) advance software, which allowed us to quantify the degree of MTA on images obtained from magnetic resonance imaging (MRI) scans. METHODS: Thirty-seven patients diagnosed with DLB were recruited and scanned with a 1.5 Tesla MRI scanner. All MRI data were analyzed using VSRAD advance. The target volume of interest (VOI) included the entire region of the entorhinal cortex, hippocampus, and amygdala. The degree of MTA was obtained from the averaged positive z-score (Z score) on the target VOI, with higher scores indicating more severe MTA. Mini-Mental State Examination (MMSE) and the Revised Hasegawa Dementia Scale (HDS-R), which strengthened the measures of memory and language more than MMSE, were used to assess the presence of cognitive impairment. RESULTS: A negative correlation was found between the Z score and MMSE total scores or the HDS-R total scores. A stepwise multiple regression analysis performed to adjust the covariate effects of sex, age, the onset age of the disease, duration of DLB, years of education, and donepezil treatment showed that the HDS-R total scores were independently associated with the Z score, whereas MMSE total scores were not. CONCLUSIONS: These results suggest that MTA is related to cognitive impairment in patients with DLB, particularly the regions of orientation, immediate and delayed recall, and word fluency.

Relationships between occupational stress and depressive symptoms among prison officers in Japan.

BACKGROUND: The relationships between occupational stress and depressive symptoms in prison officers have rarely been studied in Japan. Thus, we analyzed the associations between occupational stress factors and depressive symptoms among Japanese prison officers. METHODS: This was a cross-sectional study involving 426 male prison officers (20-60-year-old). Depressive symptoms were assessed using the Zung Self-Rating Depression Scale. Using this scale and a cut-off point of 50, the subjects were divided into the "depressive group" and "non-depressive group". Occupational stress was evaluated using the Generic Job Stress Questionnaire. Comparisons among the groups were performed with multiple logistic regression analysis. RESULTS: Of the 426 subjects, 107 were included in the depressive group. After adjusting for demographic and occupational variables, higher scores for the physical environment, role ambiguity, and quantitative workload and a lower score for social support from co-workers were found to be associated with an increased odds ratio of depressive symptoms. CONCLUSIONS: The physical environment, role ambiguity, quantitative workload, and social support from coworkers are associated with depressive symptoms in Japanese prison officers. We hope that educating prison officers about the results of this study and organizational/individual-based improvement strategies will reduce their risk of depression.

Intracerebroventricular administration of leptin increases anxiety-like behavior in female rats after semi-starvation--implications for anxiety in eating disorders.

BACKGROUND: Patients with eating disorders often exhibit abnormal eating conditions like food restriction, adipocyte and body weight reduction, and pathologic anxiety-like behavior. The role of leptin, which is recognized as an adipocyte-derived hormone, on anxiety-like behavior in eating disorders is still unclear. METHODS: We investigated the role of leptin on anxiety-like behavior with or without semi-starvation using the elevated plus-maze test in adolescent female rats. In our first experiment, anxiety-like behavior was evaluated with the elevated plus-maze test 30 min after intracerebroventricular administration of 3 microg of leptin or vehicle. In our second experiment, the rats were allowed access to food for only 2 hr each day for 7 days. Then, leptin or vehicle was administered to the rats after the last 2 hr feeding period, and anxiety-like behaviors were evaluated in the same way as in the first experiment. RESULTS: In the first experiment, there was no difference between the anxiety-like behaviors observed after leptin administration and those seen after vehicle administration. Under the conditions of semi-starvation, however, the percentage of time spent in the open arms in the rats given leptin was lower than that in rats given vehicle. CONCLUSIONS: These results suggest that leptin administration causes anxiety-like behavior only after semistarvation. Leptin might play an important role in pathologic anxiety-like behavior in eating disorders.

Corticotropin-releasing factor receptor type 1, but not type 2, in the ventromedial hypothalamus modulates dopamine release in female rats.

Corticotropin-releasing factor (CRF) plays an important role in stress responses and is mediated through two subtypes of receptors, CRF receptor type 1 (CRFR1) and CRF receptor type 2 (CRFR2). Each CRF receptor might have a different function through several neurotransmitter systems; however, the mechanism remains unclear. To clarify the role of each receptor in dopamine (DA) metabolism, we measured the change of extracellular concentrations of DA and the metabolites in the ventromedial hypothalamus (VMH) that played important roles in the stress response of freely moving female rats in response to the direct administration of comparative CRFR1 selective agonist, CRF, or CRFR2 selective agonist, Urocortin II (Ucn II), into the brain region. Administration of 10 microg CRF increased extracellular concentrations of DA compared with 2 microg CRF immediately after injection, and this effect was not observed after 60 min of 10 microg CRF injection. On the other hand, this change did not always occur after Ucn II administration. These results suggest that the activation of CRFR1, but not CRFR2, modulates the release of DA in VMH.

[Animal model of eating disorders].

Patients with eating disorders are increasing in number. Some neurocircuits concerned with feeding behavior might be dysfunctional in these patients with repeated expression of disorganized eating behavior like long-lasting dieting. These neuronal, or endocrinological dysfunctions might even be enhanced by psychological stress. To understand the biological bases of eating disorders is necessary to establish effective treatment. According to the clinical features of the patients, we have conducted some rat studies. We have found that space restriction stress enhances rebound hyperphagia induced by time-restricted scheduled feeding, and propose the phenomenon as a possible rat model of binge eating. We can speculate some part of the biological bases of human eating disorders, and effective prevention and treatment through such animal models.