Isolated catatonia-like executive dysfunction in mice with forebrain-specific loss of myelin integrity.

A key feature of advanced brain aging includes structural defects of intracortical myelin that are associated with secondary neuroinflammation. A similar pathology is seen in specific myelin mutant mice that model 'advanced brain aging' and exhibit a range of behavioral abnormalities. However, the cognitive assessment of these mutants is problematic because myelin-dependent motor-sensory functions are required for quantitative behavioral readouts. To better understand the role of cortical myelin integrity for higher brain functions, we generated mice lacking Plp1, encoding the major integral myelin membrane protein, selectively in ventricular zone stem cells of the mouse forebrain. In contrast to conventional Plp1 null mutants, subtle myelin defects were restricted to the cortex, hippocampus, and underlying callosal tracts. Moreover, forebrain-specific Plp1 mutants exhibited no defects of basic motor-sensory performance at any age tested. Surprisingly, several behavioral alterations reported for conventional Plp1 null mice (Gould et al., 2018) were absent and even social interactions appeared normal. However, with novel behavioral paradigms, we determined catatonia-like symptoms and isolated executive dysfunction in both genders. This suggests that loss of myelin integrity has an impact on cortical connectivity and underlies specific defects of executive function. These observations are likewise relevant for human neuropsychiatric conditions and other myelin-related diseases.

Going Back to Kahlbaum's Psychomotor (and GABAergic) Origins: Is Catatonia More Than Just a Motor and Dopaminergic Syndrome?

In 1874, Karl Kahlbaum described catatonia as an independent syndrome characterized by motor, affective, and behavioral anomalies. In the following years, various catatonia concepts were established with all sharing the prime focus on motor and behavioral symptoms while largely neglecting affective changes. In 21st century, catatonia is a well-characterized clinical syndrome. Yet, its neurobiological origin is still not clear because methodological shortcomings of hitherto studies had hampered this challenging effort. To fully capture the clinical picture of catatonia as emphasized by Karl Kahlbaum, 2 decades ago a new catatonia scale was developed (Northoff Catatonia Rating Scale [NCRS]). Since then, studies have used NCRS to allow for a more mechanistic insight of catatonia. Here, we undertook a systematic review searching for neuroimaging studies using motor/behavioral catatonia rating scales/criteria and NCRS published up to March 31, 2019. We included 19 neuroimaging studies. Studies using motor/behavioral catatonia rating scales/criteria depict cortical and subcortical motor regions mediated by dopamine as neuronal and biochemical substrates of catatonia. In contrast, studies relying on NCRS found rather aberrant higher-order frontoparietal networks which, biochemically, are insufficiently modulated by gamma-aminobutyric acid (GABA)-ergic and glutamatergic transmission. This is further supported by the high therapeutic efficacy of GABAergic agents in acute catatonia. In sum, this systematic review points out the difference between motor/behavioral and NCRS-based classification of catatonia on both neuronal and biochemical grounds. That highlights the importance of Kahlbaum's original truly psychomotor concept of catatonia for guiding both research and clinical diagnosis and therapy.

Metabolic profiling reveals biochemical pathways and potential biomarkers associated with the pathogenesis of Krabbe disease.

Krabbe disease (KD) is caused by mutations in the galactosylceramidase (GALC) gene, which encodes a lysosomal enzyme that degrades galactolipids, including galactosylceramide and galactosylsphingosine (psychosine). GALC deficiency results in progressive intracellular accumulation of psychosine, which is believed to be the main cause for the demyelinating neurodegeneration in KD pathology. Umbilical cord blood transplantation slows disease progression when performed presymptomatically but carries a significant risk of morbidity and mortality. Accurate presymptomatic diagnosis is therefore critical to facilitate the efficacy of existing transplant approaches and to avoid unnecessary treatment of children who will not develop KD. Unfortunately, current diagnostic criteria, including GALC activity, genetic analysis, and psychosine measurement, are insufficient for secure presymptomatic diagnosis. This study performs a global metabolomic analysis to identify pathogenetic metabolic pathways and novel biomarkers implicated in the authentic mouse model of KD known as twitcher. At a time point before onset of signs of disease, twitcher hindbrains had metabolic profiles similar to WT, with the exception of a decrease in metabolites related to glucose energy metabolism. Many metabolic pathways were altered after early signs of disease in the twitcher, including decreased phospholipid turnover, restricted mitochondrial metabolism of branched-chain amino acids, increased inflammation, and changes in neurotransmitter metabolism and osmolytes. Hypoxanthine, a purine derivative, is increased before signs of disease appear, suggesting its potential as a biomarker for early diagnosis of KD. Additionally, given the early changes in glucose metabolism in the pathogenesis of KD, diagnostic modalities that report metabolic function, such as positron emission tomography, may be useful in KD. © 2016 Wiley Periodicals, Inc.

[Comparative analysis of imipramine intake reactions in catatonic and wistar rats].

Chronic imipramine intake (7.5 mg/kg) leads to the stable decrease of excitable reactions to sound stimulant in Wistar rats and induced phase behavioral response in catatonic GC rats. Increased noradrenaline level in frontal cortex and striatum in Wistar animals was shown, whereas it didn't reveal noradrenaline level differences in any brain structures in GC rats. The higher blood corticosterone concentration was decreased under antidepressant reaction in GC rats. Differences between intact GC animals were found out: reduced triglyceride level, lesser body weight, and greater weight index of adrenals in comparison with Wistar rats. Various mechanisms of imipramine action in two rat strains were shown: influence on adrenergic brain system, taking part in the control of exiting behavior in Wistar rats and reaction in adrenals in GC rats.

Management of psychiatric symptoms in anti-NMDAR encephalitis: a case series, literature review and future directions.

Anti-NMDA receptor (NMDAR) encephalitis, formally recognized in 2007, has been increasingly identified as a significant cause of autoimmune and paraneoplastic encephalitis. Approximately 80% of the patients are females. The characteristic syndrome evolves in several stages, with approximately 70% of the patients presenting with a prodromal phase of fever, malaise, headache, upper respiratory tract symptoms, nausea, vomiting and diarrhoea. Next, typically within two weeks, patients develop psychiatric symptoms including insomnia, delusions, hyperreligiosity, paranoia, hallucinations, apathy and depression. Catatonic symptoms, seizures, abnormal movements, autonomic instability, memory deficits may also develop during the course of the disease. Presence of antibodies against the GluN1 subunit of the NMDAR in the CSF and serum confirm the diagnosis of NMDAR encephalitis, which also should prompt a thorough search for an underlying tumor. Age, gender, and ethnicity may all play a role, as black females older than 18 years of age have an increased likelihood of an underlying tumor. Treatment is focused on tumor resection and first-line immunotherapy [corticosteroids, plasma exchange, and intravenous immunoglobulin]. In non-responders, second- line immunotherapy [rituximab or cyclophosphamide or combined] is required. More than 75% of the patients recover completely or have mild sequelae, while the remaining patients end up demonstrating persistent severe disability or death. There is a paucity of literature on the management of psychiatric symptoms in this population. Given the neuropsychiatric symptoms in the relatively early phase of the illness, approximately 77 % of the patients are first evaluated by a psychiatrist. Earlier recognition of this illness is of paramount importance as prompt diagnosis and treatment can potentially improve prognosis. We describe two patients diagnosed with NMDAR encephalitis presenting with two different psychiatric manifestations. The first patient presented with psychotic mania and catatonic symptoms, while the second suffered from depression with psychotic and catatonic features refractory to psychotropic medications. We review of the use of psychotropic medications and ECT to address insomnia, agitation, psychosis, mood dysregulation and catatonia in NMDAR encephalitis.

[Selection for catatonic reaction in rats: a study of interstrain differences by magnetic resonance imaging].

Brain studies by magnetic resonance imaging, angiography, and spectroscopy have been performed with rat strains Wistar, GC (genetic and catatonia), and PM+ (pendulum movements). Both GC and PM+ rats show similar deviations from the ancestral Wistar population in having smaller areas of the right striatum (coronal slice). The anterior horns of lateral ventricles in GC rats are smaller than in the control strain. The maximum blood flow velocity in the common carotid arteries of PM+ rats is greater. The GC and PM+ strains differ in myo-inositol level in the hippocampus. The PM+ strain is characterized by a lower taurine level in the hippocampus, which may be one of the participants regulated the predisposition to audiogenic seizures.

Central dopamine D2 receptors regulate growth-hormone-dependent body growth and pheromone signaling to conspecific males.

Competition between adult males for limited resources such as food and receptive females is shaped by the male pattern of pituitary growth hormone (GH) secretion that determines body size and the production of urinary pheromones involved in male-to-male aggression. In the brain, dopamine (DA) provides incentive salience to stimuli that predict the availability of food and sexual partners. Although the importance of the GH axis and central DA neurotransmission in social dominance and fitness is clearly appreciated, the two systems have always been studied unconnectedly. Here we conducted a cell-specific genetic dissection study in conditional mutant mice that selectively lack DA D2 receptors (D2R) from pituitary lactotropes (lacDrd2KO) or neurons (neuroDrd2KO). Whereas lacDrd2KO mice developed a normal GH axis, neuroDrd2KO mice displayed fewer somatotropes; reduced hypothalamic Ghrh expression, pituitary GH content, and serum IGF-I levels; and exhibited reduced body size and weight. As a consequence of a GH axis deficit, neuroDrd2KO adult males excreted low levels of major urinary proteins and their urine failed to promote aggression and territorial behavior in control male challengers, in contrast to the urine taken from control adult males. These findings reveal that central D2Rs mediate a neuroendocrine-exocrine cascade that controls the maturation of the GH axis and downstream signals that are critical for fitness, social dominance, and competition between adult males.

[The increase in the proportion of nervous animals bred for catatonia: the participation of central adrenoreceptors in catatonic reactions].

Using a large amount of breeding material, the idea of D. K. Belyaev on the role of selection in the appearance of new behavioral and neuronal forms was confirmed. Experiments were performed using rats of the GC (genetics + catatonia) strain, which are prone to passive defensive reactions of cataleptic freezing. At the current breeding stage, elevation of the proportion of so-called nervous animals was demonstrated, both with respect to the expression of such reactions and their frequency. At this breeding stage, in the brains of GC rats, the mRNA levels of alpha1A- and alpha2A-adrenoreceptor genes were determined. A decrease of alpha1A-adrenoreceptor gene expression in the midbrain and medulla oblongata, along with elevation of alpha2A-adrenoreceptor gene expression in the frontal cortex was observed. It was suggested that changes in the expression of alpha-adrenoreceptor genes could be caused by an increase in the proportion of nervous animals and could contribute to the akinetic behavioral component in GC rats.

[Monoamines and function of the ovaries in rats selected for elevated catatonic reactivity].

Levels of dopamine (DOPA), noradrenalin (NA), and serotonin in hypothalamus and function of ovaries (folliculogenesis) were studied at various estrous cycle stages of the rat GK line selected for elevated catatonia. The control was the outbred Wistar line. Selection for elevated catatonia led to a decrease of the number of all cell types in GK ovaries in diestrus and proestrus. In estrus of the GK females, on the contrary, there was a tendency for an increase of the number of the growing follicles as compared with Wistar females. On the background of a decrease of the DOPA and NA content in hypothalamus of the GK line rats, the higher catecholamine level was observed in estrus and the lower--in diestrus. Thus, selection for manifestation of the excessive protective catatonical type of reaction in the form of an increase of duration and intensity of freezing involves the monoaminergic brain system and leads to delay of folliculogenesis that is the key factor in regulation of fertility.

Impairment of the cortical GABAergic inhibitory system in catatonic stupor: a case report with neuroimaging.

We report the case of a 32-year-old patient who presented with catatonic stupor during the course of acute aseptic encephalitis involving the right frontotemporal area. Flumazenil-PET performed during the stupor indicated decreased benzodiazepine receptor binding in the right frontotemporal area where glucose metabolism was preserved as revealed by FDG-PET. An injection of diazepam immediately ameliorated catatonic symptoms and reduced widespread high amplitude slow EEG activities with right frontotemporal predominance. Compared with a SPECT study performed a week earlier, there was no abnormal right-sided anteriorly predominant cerebral hyperperfusion after injection of diazepam. While neither flumazenil- nor FDG-PET could be repeated, and with the caveat that generalized convulsions occurred initially and epilepsia partialis continua was present for two weeks starting on the 23rd day after illness onset, these findings suggest that in our case the presentation with catatonic stupor may be related to impairment of the cortical GABAergic inhibitory system.

Effect of M4-cholinoceptor blockade on haloperidol-produced catatonic syndrome in rats.

We studied the relationship between the efficiency of muscarinic receptor antagonists in preventing haloperidol-induced catatonia and their activity in tests for the interaction of ligands with various subtypes of muscarinic receptors (M1-M4) in rats. Mathematical modeling showed that affinity of the ligand for M4 receptors positively affects its ability to correct extrapyramidal disorders (catatonic syndrome) produced by haloperidol, while affinity for M2 receptors had a negative effect on this characteristic.

Decreased density of GABA-A receptors in the left sensorimotor cortex in akinetic catatonia: investigation of in vivo benzodiazepine receptor binding.

OBJECTIVES: Catatonia is a psychomotor syndrome with concomittant akinesia and anxiety which both respond almost immediately to benzodiazepines such as lorazepam. The benzodiazepine receptor distribution was therefore investigated in akinetic catatonia with single photon emission tomography (SPECT) using iodine-123-iomazenil ((123) I Iomazenil). METHODS: Ten akinetic catatonic patients, 10 psychiatric controls (similar age, sex, medication, and underlying psychiatric diagnosis but without catatonic syndrome), and 20 healthy controls were investigated with SPECT 2 hours after injection of (123) I Iomazenil. To exclude potential effects of cerebral perfusion (r-CBF) r-CBF was additionally investigated with Tc-99mECD SPECT. RESULTS: Catatonic patients showed significantly lower iomazenil binding and altered right-left relations in the left sensorimotor cortex compared with psychiatric (p<0.001) and healthy (p<0.001) controls. In addition, there was significantly lower r-CBF in the right lower prefrontal and parietal cortex in catatonia whereas in the left sensorimotor cortex no differences in r-CBF between groups were found. Catatonic motor and affective symptoms showed significant correlations (p<0.05) with benzodiazepine binding in the left sensorimotor cortex as well as with right parietal r-CBF. CONCLUSIONS: Reduced iomazenil binding suggests decreased density of GABA-A receptors in the left sensorimotor cortex in akinetic catatonia. In addition to reduced GABA-A receptor density in the left sensorimotor cortex the parietal cortex seems to be involved in pathophysiology of catatonic symptoms. It is concluded that, considering results from correlation analyses, both emotional and motor symptoms in catatonia seem to be closely related to left sensorimotor and right parietal alterations.

Glutamatergic dysfunction in catatonia? Successful treatment of three acute akinetic catatonic patients with the NMDA antagonist amantadine.

Therapeutic efficiacy of the NMDA antagonist amantadine is reported in three acute neuroleptic free akinetic catatonic patients. Intravenous infusion of amantadine led to the resolution of catatonic symptoms and considerable reductions of scores in various motor scales (Simpson Angus scale for extrapyramidal side effects (SEPS), the abnormal involuntary movement scale (AIMS), Rogers catatonia and schizophrenia scales). The therapeutic effect of amantadine showed a characteristic temporal pattern with most pronounced effects four to six hours after administration and recurrence of catatonic symptoms by 24 hours later, at least partially. Such a temporal pattern of therapeutic efficacy and decreasing efficacy occurred in all three patients on all days. The results suggest the central importance of glutamatergic dysfunction in catatonic syndrome.

Catatonia: short-term response to lorazepam and dopaminergic metabolism.

Therapeutic response to lorazepam and dopaminergic metabolism were investigated in 18 neuroleptically naive acute catatonic patients. They were diagnosed as catatonic according to criteria by Lohr and Rosebush and treated exclusively with lorazepam (2-4 mg) during the first 24 h. Dopaminergic metabolism (plasma HVA, plasma MHPG), anxiety (HAM-A) and parkinsonic/dyskinetic movements (SEPS, AIMS) were measured under standard conditions before initial treatment with lorazepam (day 0) and 24 h after initial treatment (day 1). On day 0 responders to lorazepam treatment (complete remission of catatonic syndrome after 24 h according to Rosebush and Lohr) showed significantly higher (P = 0.004) plasma HVA (130.4 +/- 51.2 pmol/ml; means +/- SD) than non-responders (no remission of catatonic syndrome after 24 h; 73.2 +/- 40.5 pmol/ml; means +/- SD). On day 1 plasma HVA did not differ any more significantly between both groups Clinically, responders showed significantly higher HAM-A (P = 0.025) and AIMS (P = 0.022) scores as well as significantly lower SEPS (P = 0.049) scores than non-responders on day 0. Hence catatonic short-term responders and nonresponders to lorazepam can be distinguished with regard to plasma HVA, anxiety and dyskinetic/parkinsonic movements.

Receptor binding in Japanese quail selected for long or short tonic immobility.

Japanese quail, selectively bred for long (LTI) and short (STI) tonic immobility (TI) responses, are thought to represent high and low fear groups, respectively. To study the neurochemical mechanisms underlying the behavioral distinctions, binding parameters were determined at the benzodiazepine, 5-HT1A, 5-HT3, alpha 2, and opioid receptor sites in the forebrains of the two lines. No differences were found in 5-HT1A, 5-HT3, alpha 2, mu- or kappa-opioid receptor binding between the lines. The KD for the binding of [3H]-flunitrazepam at the benzodiazepine receptor was significantly greater in the LTI than in the STI birds, indicating lower affinity for benzodiazepine ligands. The lines did not differ in benzodiazepine receptor number. Using [3H]-naltrindole, the LTI line was found to have fewer delta-opioid receptors than the STI line; the birds did not vary with respect to the affinity of these receptors. Thus, the selective breeding of the two lines has resulted in differences in benzodiazepine and delta-opioid binding, and these could produce differences in activity levels, fear, and pain responses, all of which could contribute to the tonic immobility response.

Brain neurotransmitter changes in three patients who had a fatal hyperthermia syndrome.

The authors examined the autopsied brains from three patients who had a fatal hyperthermia syndrome. There was marked hypothalamic noradrenaline depletion in all three patients, severe brain choline acetyltransferase deficiency with nucleus basalis cell loss in two patients, and mild to moderate brain choline acetyltransferase loss in one patient. Striatal dopamine metabolite/dopamine ratio was below normal in two patients and not elevated, as would be expected after short-term neuroleptic administration, in the third. This suggests that reduced capability (aggravated by the cholinergic deficit) of the nigrostriatal dopamine system to respond adequately to stress and/or neuroleptic-induced receptor blockade may be important in the development and course of fatal hyperthermia syndrome.