Medial prefrontal area reductions, altered expressions of cholecystokinin, parvalbumin, and activating transcription factor 4 in the corticolimbic system, and altered emotional behavior in a progressive rat model of type 2 diabetes

Metabolic disorders are associated with a higher risk of psychiatric disorders. We previously reported that 20-week-old Otsuka Long-Evans Tokushima fatty (OLETF) rats, a model of progressive type 2 diabetes, showed increased anxiety-like behavior and regional area reductions and increased cholecystokinin-positive neurons in the corticolimbic system. However, in which stages of diabetes these alterations in OLETF rats occur remains unclear. We aimed to investigate anxiety-like behavior and its possible mechanisms at different stages of type 2 diabetes in OLETF rats. Eight- and 30-week-old OLETF rats were used as diabetic animal models at the prediabetic and progressive stages of type 2 diabetes respectively, and age-matched Long-Evans Tokushima Otsuka rats served as non-diabetic controls. In the open-field test, OLETF rats showed less locomotion in the center zone and longer latency to leave the center zone at 8 and 30 weeks old, respectively. The areas of the medial prefrontal cortex were smaller in the OLETF rats, regardless of age. The densities of cholecystokinin-positive neurons in OLETF rats were higher in the lateral and basolateral amygdala only at 8 weeks old and in the anterior cingulate and infralimbic cortices and hippocampal cornu ammonis area 3 at both ages. The densities of parvalbumin-positive neurons of OLETF rats were lower in the cornu ammonis area 2 at 8 weeks old and in the prelimbic and infralimbic cortices at both ages. No apoptotic cell death was detected in OLETF rats, but the percentage of neurons co-expressing activating transcription factor 4 and cholecystokinin and parvalbumin was higher in OLETF rats at both ages in the anterior cingulate cortex and basolateral amygdala, respectively. These results suggest that altered emotional behavior and related neurological changes in the corticolimbic system are already present in the prediabetic stage of OLETF rats.

Food Entrainment, Arousal, and Motivation in the Neonatal Rabbit Pup

In the newborn rabbit, the light entrainable circadian system is immature and once a day nursing provides the primary timing cue for entrainment. In advance of the mother’s arrival, pups display food anticipatory activity (FAA), and metabolic and physiological parameters are synchronized to this daily event. Central structures in the brain are also entrained as indicated by expression of Fos and Per1 proteins, GFAP, a glial marker, and cytochrome oxidase activity. Under fasting conditions, several of these rhythmic parameters persist in the periphery and brain, including rhythms in the olfactory bulb (OB). Here we provide an overview of these physiological and neurobiological changes and focus on three issues, just beginning to be examined in the rabbit. First, we review evidence supporting roles for the organum vasculosum of lamina terminalis (OVLT) and median preoptic nucleus (MnPO) in homeostasis of fluid ingestion and the neural basis of arousal, the latter which also includes the role of the orexigenic system. Second, since FAA in association with the daily visit of the mother is an example of conditioned learning, we review evidence for changes in the corticolimbic system and identified nuclei in the amygdala and extended amygdala as part of the neural substrate responsible for FAA. Third, we review recent evidence supporting the role of oxytocinergic cells of the paraventricular hypothalamic nucleus (PVN) as a link to the autonomic system that underlies physiological events, which occur in preparation for the upcoming next daily meal. We conclude that the rabbit model has contributed to an overall understanding of food entrainment.

Targeting the Endocannabinoid System in Borderline Personality Disorder

: Borderline Personality Disorder (BPD) is a chronic debilitating psychiatric disorder characterized mainly by emotional instability, chaotic interpersonal relationships, cognitive disturbance (e.g. dissociation and suicidal thoughts) and maladaptive behaviors. BPD has a high rate of comorbidity with other mental disorders and high burden on society. In this review, we focus on two compromised brain regions in BPD – the hypothalamus and the corticolimbic system, emphasizing the involvement and potential contribution of the endocannabinoid system (ECS) to improvement in symptoms and coping. The hypothalamus-regulated endocrine axes (hypothalamic pituitary – gonadal, thyroid & adrenal) have been found to be dysregulated in BPD. There is also substantial evidence for limbic system structural and functional changes in BPD, especially in amygdala and hippocampus, including cortical regions within the corticolimbic system. Extensive expression of CB1 and CB2 receptors of the ECS has been found in limbic regions and the hypothalamus. This opens new windows of opportunity for treatment with cannabinoids such as cannabidiol (CBD) as no other pharmacological treatment has shown long-lasting improvement in the BPD population to date. This review aims to show the potential role of the ECS in BPD patients through their most affected brain regions, the hypothalamus and the corticolimbic system. The literature reviewed does not allow for general indications of treatment with CBD in BPD. However, there is enough knowledge to indicate a treatment ratio of high level of CBD to low level of THC. A randomized controlled trial investigating the efficacy of cannabinoid based treatments in BPD is warranted.

Neuropsychiatric characteristics of antiterrorist operation combatants in the Donbass (Ukraine)

ObjectiveThe present paper aimed to explore the neuropsychiatric characteristics of the antiterrorism (ATO) combatants in the Donets Basin (Donbass) and to propose therapeutic strategies for managing their mental healthcare.MethodsA total of 54 ATO combatants were included in our study and compared with four groups of subjects exposed to other emergencies, including the Chernobyl disaster and the war in Afghanistan. The neuropsychiatric features were assessed through psychopathological assessments, neurological examinations, and quantitative electroencephalography (qEEG).ResultsThe ATO combatants were characterized by low health self-estimation, somatic concerns, a high prevalence of posttraumatic stress disorder, anxiety, insomnia, depression, social dysfunction, mild cognitive impairment, and neurological soft signs, similar to individuals involved in the Chernobyl disaster and veterans of the Afghan War. Quantitative EEG showed abnormalities suggestive of irritation of the corticolimbic system and diencephalic structures. Some post-conflict personality changes in ATO combatants were recorded. The treatment of ATO combatants included a comprehensive strategy: from psychotropic drugs to different psychotherapies.ConclusionsOn the basis of 30 years of experience in the management of the consequences of Chernobyl disaster and the available studies on war veterans, the authors proposed a method for assessment and an approach to providing mental healthcare for ATO combatants, refugees, and migrants from the Donbass, which perhaps can be used as guidelines for other conflicts. Taken together, the findings of the study suggest that voluntary participation in war may decrease but does not eliminate the risk of developing the neuropsychiatric consequences caused by such conflicts. A comprehensive strategy—one that would encompass psychopharmacological, psychological, and rehabilitation techniques—seems to be the most successful approach to managing the main symptoms and disorders involved.