Repetitive and compulsive behavior after Early-Life-Pain associated with reduced long-chain sphingolipid species.

BACKGROUND: Pain in early life may impact on development and risk of chronic pain. We developed an optogenetic Cre/loxP mouse model of "early-life-pain" (ELP) using mice with transgenic expression of channelrhodopsin-2 (ChR2) under control of the Advillin (Avil) promoter, which drives expression of transgenes predominantly in isolectin B4 positive non-peptidergic nociceptors in postnatal mice. Avil-ChR2 (Cre +) and ChR2-flfl control mice were exposed to blue light in a chamber once daily from P1-P5 together with their Cre-negative mother. RESULTS: ELP caused cortical hyperexcitability at P8-9 as assessed via multi-electrode array recordings that coincided with reduced expression of synaptic genes (RNAseq) including Grin2b, neurexins, piccolo and voltage gated calcium and sodium channels. Young adult (8-16 wks) Avil-ChR2 mice presented with nociceptive hypersensitivity upon heat or mechanical stimulation, which did not resolve up until one year of age. The persistent hypersensitivy to nociceptive stimuli was reflected by increased calcium fluxes in primary sensory neurons of aged mice (1 year) upon capsaicin stimulation. Avil-ChR2 mice behaved like controls in maze tests of anxiety, social interaction, and spatial memory but IntelliCage behavioral studies revealed repetitive nosepokes and corner visits and compulsive lickings. Compulsiveness at the behavioral level was associated with a reduction of sphingomyelin species in brain and plasma lipidomic studies. Behavioral studies were done with female mice. CONCLUSION: The results suggest that ELP may predispose to chronic "pain" and compulsive psychopathology in part mediated by alterations of sphingolipid metabolism, which have been previously described in the context of addiction and psychiatric diseases.

Metal-Organic Framework Mediated Radio-Enhancement Assessed in High-Throughput-Compatible 3D Tumor Spheroid Co-Cultures.

Inorganic nanomaterials have gained increasing attention in radiation oncology, owing to their radiation therapy enhancing properties. To accelerate candidate material selection and overcome the disconnect between conventional 2D cell culture and in vivo findings, screening platforms unifying high-throughput with physiologically relevant endpoint analysis based on 3D in vitro models are promising. Here, a 3D tumor spheroid co-culture model based on cancerous and healthy human cells is presented for the concurrent assessment of radio-enhancement efficacy, toxicity, and intratissural biodistribution with full ultrastructural context of radioenhancer candidate materials. Its potential for rapid candidate materials screening is showcased based on the example of nano-sized metal-organic frameworks (nMOFs) and direct benchmarking against gold nanoparticles (the current "gold standard"). Dose enhancement factors (DEFs) ranging between 1.4 and 1.8 are measured for Hf-, Ti-, TiZr-, and Au-based materials in 3D tissues and are overall lower than in 2D cell cultures, where DEF values exceeding 2 are found. In summary, the presented co-cultured tumor spheroid-healthy fibroblast model with tissue-like characteristics may serve as high-throughput platform enabling rapid, cell line-specific endpoint analysis for therapeutic efficacy and toxicity assessment, as well as accelerated radio-enhancer candidate screening.

Phosphatidylethanolamine Deficiency and Triglyceride Overload in Perilesional Cortex Contribute to Non-Goal-Directed Hyperactivity after Traumatic Brain Injury in Mice.

Traumatic brain injury (TBI) is often complicated by long-lasting disabilities, including headache, fatigue, insomnia, hyperactivity, and cognitive deficits. In a previous study in mice, we showed that persistent non-goal-directed hyperactivity is a characteristic post-TBI behavior that was associated with low levels of endocannabinoids in the perilesional cortex. We now analyzed lipidome patterns in the brain and plasma in TBI versus sham mice in association with key behavioral parameters and endocannabinoids. Lipidome profiles in the plasma and subcortical ipsilateral and contralateral brain were astonishingly equal in sham and TBI mice, but the ipsilateral perilesional cortex revealed a strong increase in neutral lipids represented by 30 species of triacylglycerols (TGs) of different chain lengths and saturation. The accumulation of TG was localized predominantly to perilesional border cells as revealed by Oil Red O staining. In addition, hexosylceramides (HexCer) and phosphatidylethanolamines (PE and ether-linked PE-O) were reduced. They are precursors of gangliosides and endocannabinoids, respectively. High TG, low HexCer, and low PE/PE-O showed a linear association with non-goal-directed nighttime hyperactivity but not with the loss of avoidance memory. The analyses suggest that TG overload and HexCer and PE deficiencies contributed to behavioral dimensions of post-TBI psychopathology.

Increased Fat Taste Preference in Progranulin-Deficient Mice.

Progranulin deficiency in mice is associated with deregulations of the scavenger receptor signaling of CD36/SCARB3 in immune disease models, and CD36 is a dominant receptor in taste bud cells in the tongue and contributes to the sensation of dietary fats. Progranulin-deficient mice (Grn-/-) are moderately overweight during middle age. We therefore asked if there was a connection between progranulin/CD36 in the tongue and fat taste preferences. By using unbiased behavioral analyses in IntelliCages and Phenomaster cages we showed that progranulin-deficient mice (Grn-/-) developed a strong preference of fat taste in the form of 2% milk over 0.3% milk, and for diluted MCTs versus tap water. The fat preference in the 7d-IntelliCage observation period caused an increase of 10% in the body weight of Grn-/- mice, which did not occur in the wildtype controls. CD36 expression in taste buds was reduced in Grn-/- mice at RNA and histology levels. There were no differences in the plasma or tongue lipids of various classes including sphingolipids, ceramides and endocannabinoids. The data suggest that progranulin deficiency leads to a lower expression of CD36 in the tongue resulting in a stronger urge for fatty taste and fatty nutrition.

Deletion of the Na-K-2Cl cotransporter NKCC1 results in a more severe epileptic phenotype in the intrahippocampal kainate mouse model of temporal lobe epilepsy.

Increased neuronal expression of the Na-K-2Cl cotransporter NKCC1 has been implicated in the generation of seizures and epilepsy. However, conclusions from studies on the NKCC1-specific inhibitor, bumetanide, are equivocal, which is a consequence of the multiple potential cellular targets and poor brain penetration of this drug. Here, we used Nkcc1 knockout (KO) and wildtype (WT) littermate control mice to study the ictogenic and epileptogenic effects of intrahippocampal injection of kainate. Kainate (0.23 µg in 50 nl) induced limbic status epilepticus (SE) in both KO and WT mice with similar incidence, latency to SE onset, and SE duration, but the number of intermittent generalized convulsive seizures during SE was significantly higher in Nkcc1 KO mice, indicating increased SE severity. Following SE, spontaneous recurrent seizures (SRS) were recorded by continuous (24/7) video/EEG monitoring at 0-1, 4-5, and 12-13 weeks after kainate, using depth electrodes in the ipsilateral hippocampus. Latency to onset of electrographic SRS and the incidence of electrographic SRS were similar in WT and KO mice. However, the frequency of electrographic seizures was lower whereas the frequency of electroclinical seizures was higher in Nkcc1 KO mice, indicating a facilitated progression from electrographic to electroclinical seizures during chronic epilepsy, and a more severe epileptic phenotype, in the absence of NKCC1. The present findings suggest that NKCC1 is dispensable for the induction, progression and manifestation of epilepsy, and they do not support the widely held notion that inhibition of NKCC1 in the brain is a useful strategy for preventing or modifying epilepsy.

Mnemonic discrimination is associated with individual differences in anxiety vulnerability.

Increased generalization between fear-inducing stimuli (e.g., looking over the edge of a tall building) and perceptually-similar neutral stimuli (e.g., an aerial photograph) is observed in all subtypes of anxiety disorders, leading to avoidance behaviors that feed forward from the feared stimulus to other, seemingly unrelated stimuli. However, recent research suggests a much more nuanced relationship between generalization, discrimination, and behavior. This study seeks to extend current understanding by using a mnemonic discrimination task to explore the relationship between risk for anxiety and differences in mnemonic discrimination abilities. Participants self-reported trait anxiety and behavioral inhibition (a temperamental construct linked to risk for anxiety), and also completed a memory task. After incidental encoding of color photographs of neutral everyday objects, participants performed a surprise recognition task, where they categorized each test image as "old" (identical to a previously viewed image), "similar" (new but perceptually-similar to a studied image, with half the images being highly similar and the other half being less similar to the studied images), or "new" (new and perceptually-dissimilar to studied images). We found that those with high behavioral inhibition are more successful at discriminating between previously seen "old" items from highly similar items. In contrast, those with high trait anxiousness are less successful at the same kind of discrimination. Interestingly, these relationships were not apparent in low similarity items. Our data suggest that behavioral inhibition and trait anxiety may be associated with unique aspects of individual differences in mnemonic discrimination abilities.

Low brain endocannabinoids associated with persistent non-goal directed nighttime hyperactivity after traumatic brain injury in mice.

Traumatic brain injury (TBI) is a frequent cause of chronic headache, fatigue, insomnia, hyperactivity, memory deficits, irritability and posttraumatic stress disorder. Recent evidence suggests beneficial effects of pro-cannabinoid treatments. We assessed in mice levels of endocannabinoids in association with the occurrence and persistence of comparable sequelae after controlled cortical impact in mice using a set of long-term behavioral observations in IntelliCages, motor and nociception tests in two sequential cohorts of TBI/sham mice. TBI mice maintained lower body weights, and they had persistent low levels of brain ethanolamide endocannabinoids (eCBs: AEA, OEA, PEA) in perilesional and subcortical ipsilateral brain tissue (6 months), but rapidly recovered motor functions (within days), and average nociceptive responses were within normal limits, albeit with high variability, ranging from loss of thermal sensation to hypersensitivity. TBI mice showed persistent non-goal directed nighttime hyperactivity, i.e. they visited rewarding and non-rewarding operant corners with high frequency and random success. On successful visits, they made more licks than sham mice resulting in net over-licking. The lower the eCBs the stronger was the hyperactivity. In reward-based learning and reversal learning tasks, TBI mice were not inferior to sham mice, but avoidance memory was less stable. Hence, the major late behavioral TBI phenotype was non-goal directed nighttime hyperactivity and "over-licking" in association with low ipsilateral brain eCBs. The behavioral phenotype would agree with a "post-TBI hyperactivity disorder". The association with persistently low eCBs in perilesional and subcortical regions suggests that eCB deficiency contribute to the post-TBI psychopathology.

Distal infraorbital nerve injury: a model for persistent facial pain in mice.

Inflammation or injuries of the trigeminal nerve are often associated with persistent facial pain and its sequelae. A number of models have been described to study trigeminal pain in rodents, but the long-lasting behavioral consequences are unknown. This study characterizes the impact of a distal infraorbital nerve injury, called DIONI, which consists of ligature and transection of distal fibers of the infraorbital nerve. We assessed nociception using a conflict paradigm and optogenetics, and a set of reward, aversion, spatial, temporal, and competition tasks in the IntelliCage to study multiple aspects of cognition, circadian rhythms, and social interactions in groups of mice in home cage environments. Mice with DIONI developed cold and mechanical allodynia, and hypersensitivity towards blue light stimulation. They maintained a long-lasting memory of aversive stimuli (airpuff from above), but had no difficulty in learning appetitive tasks, which consisted in developing a preference for a rewarding corner in the IntelliCage. Indeed, they were more strongly "addicted" to sugar than sham mice but temporarily failed to relearn the location of rewarding sites after corner switching (reversal learning). They were mildly overactive in some tasks but without disruptions of circadian rhythms or impact on social structure. They adopted a strategy to maintain licking with fewer nosepokes, presumably trying to avoid mechanical stimulation of the snout. The results suggest that mice with DIONI develop strong aversive memories and some cognitive inflexibility, but create adaptive strategies to cope with the persistent trigeminal hypersensitivity.

Gender differences in caregiver burden and its determinants in family members of terminally ill cancer patients.

OBJECTIVE: Female family caregivers consistently report higher levels of stress and burden compared to male caregivers. Explanations for the apparently higher psychological vulnerability of female caregivers are largely missing to date. This study assesses the correlates and determinants of caregiver burden in family caregivers of advanced cancer patients with a specific focus on gender differences. METHODS: Three hundred and eight self-identified main informal caregivers of advanced cancer patients were cross-sectionally assessed using structured questionnaires for caregiver burden and hypothesised determinants of burden, including sociodemographic characteristics, caring arrangements, support needs, hope and coping style. Gender differences and predictors of burden were assessed using t-tests, chi-squared tests and univariate linear regression. Significant univariate predictors were entered in an analysis of covariance separately for men and women. RESULTS: Burden was significantly higher in women. Hope was the most significant protective factor against burden in both genders, together with perceived fulfilment of support needs. Only in women emotion-oriented coping and being in employment while caring were significantly predictive of higher burden in the multivariate analysis. The model explained 36% of the variance in burden in men and 29% in women. CONCLUSION: Psychological support interventions for family caregivers should take gender-specific risk factors into account. Interventions focusing on keeping up hope while caring for a terminally ill family member may be a valuable addition to palliative services to improve support for family carers. Women may benefit from interventions that address adaptive coping and strategies to deal with the dual demands of employment and caring. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Validation of the Family Inventory of Needs (FIN) for family caregivers in palliative care.

OBJECTIVE: Caregivers of cancer patients are faced with significant demands that can seriously impact their physical and mental health. It is important for healthcare professionals to be aware of caregivers' support needs in order for these to be adequately addressed. Our study develops a German version of the Family Inventory of Needs (FIN) and provides a comprehensive evaluation of its acceptability and psychometric properties. METHOD: Cross-sectional data from 308 participants were taken from the baseline assessment of an ongoing prospective study. Retests were completed by 46 participants approximately one week after baseline. Informal caregivers of terminally ill cancer patients were recruited from three hospitals in Vienna. Questionnaires for hope (IHS), traumatic stress (IES-R), and depression and anxiety (HADS) were employed together with the translated FIN to assess concurrent and discriminant validity. RESULTS: The internal consistency of FIN-Importance had a Cronbach's α of 0.94, and that for FIN-Fulfillment was α = 0.96. Retest reliability for FIN-Importance was r = 0.97, while that for FIN-Fulfillment could not be calculated due to missing responses to this subscale. Concurrent and discriminant validity tests for the scale and the discriminative power of items were adequate. However, missing responses may limit the feasibility of using this scale in research settings. We identified six questions that could be excluded from the scale in order to increase its acceptability and further improve its psychometric properties. SIGNIFICANCE OF RESULTS: Our results suggest that the FIN is suitable for clinical settings. For use in research, we suggest four adaptations to increase the scale's acceptability and psychometric properties. The FIN can be a valuable tool for informing the emotional, physical, and psychological support provided to family carers of people who are terminally ill with cancer.

Validation of the "Quality of Life in Life-Threatening Illness--Family Carer Version" (QOLLTI-F) in German-speaking carers of advanced cancer patients.

BACKGROUND: Palliative care is a multidisciplinary approach that focuses on the improvement of quality of life (QOL) of patients as well as their families. QOL research in palliative care has so far primarily focused on patients, but interest in the QOL of their relatives is increasing. For instruments measuring QOL in relatives, data on psychometric properties are often limited, and so far, none has been available in German. OBJECTIVE: This study translates and validates the "Quality of Life in Life-Threatening Illness-Family Carer Version" (QOLLTI-F) in German-speaking carers of advanced cancer patients. METHODS: The QOLLTI-F was translated from English into German according to the World Health Organisation's recommendations and validated in informal caregivers of terminally ill cancer patients of three Viennese hospitals. Hope was measured to assess concurrent validity; traumatic stress, anxiety, depression and subjective burden were measured to assess discriminant validity. Internal consistency, test-retest reliability and discriminative power were established. The scale's factor structure was explored using a set of factor analyses. RESULTS: Of the 308 caregivers participating in the study, 42 completed the QOLLTI-F retest after a mean of 5 days. The internal consistency was α = 0.85 for the overall scale, Pearson correlation between test and retest lay at r = 0.92. As expected, a significant positive correlation was found with hope (r = 0.40) and significant negative correlations with traumatic stress (r = -0.41), depression (r = -0.51), anxiety (r = -0.52) and overall subjective burden (r = -0.55). The original seven-factor structure was not reproduced, but the scale showed a stable four-factor structure with factors capturing (1) feelings about carers' own life, (2) professional care, (3) interaction with the patient and others and (3) carers' outlook on life. CONCLUSION: This study provides a sound translation and validation of the first QOL assessment tool for caregivers of palliative care patients in German. It also adds to the knowledge on the scale's psychometric properties, which prove to be highly satisfactory. The QOLLTI-F may serve as an outcome measure in palliative care practice, clinical trials and epidemiological research.