Neuroscience
-
Children and adolescents have the highest rates of traumatic brain injury (TBI), with mild TBI (mTBI) accounting for most of these injuries. Adolescents are particularly vulnerable and often suffer from post-injury symptomologies that may persist for months. We hypothesized that the combination of resveratrol (RES), prebiotic fiber (PBF), and omega-3 fatty acids (docosahexaenoic acid (DHA)) would be an effective therapeutic supplement for the mitigation of mTBI outcomes in the developing brain. ⋯ A behavioral test battery designed to examine symptomologies commonly associated with mTBI was administered. Following the test battery, tissue was collected from the prefrontal cortex (PFC) and primary auditory cortex for Golgi-Cox analysis of spine density, and for changes in expression of 6 genes (Aqp4, Gfap, Igf1, Nfl, Sirt1, and Tau). 3S treatment altered the behavioral performance of sham animals indicating that dietary manipulations modify premorbid characteristics. 3S treatment prevented injury-related deficits in the longer-term behavior measures, medial prefrontal cortex (mPFC) spine density, and levels of Aqp4, Gfap, Igf1, Nfl, and Sirt1 expression in the PFC. Although not fully protective, treatment with the supplement significantly improved post-mTBI function and warrants further investigation.
-
Previous studies have shown that leptin resistance is a key feature that leads to gestational metabolic adaptions. We hypothesized that leptin sensitivity in the ventromedial nucleus of the hypothalamus (VMH) plays a critical role regulating gestational metabolic changes. In the present study, we generated a mouse model carrying ablation of the suppressor of cytokine signaling 3 (SOCS3) in steroidogenic factor-1 (SF1) cells, which include the VMH, in order to investigate whether increased leptin sensitivity in this neuronal population prevents at least part of the metabolic changes typically observed during gestation and lactation. ⋯ Unexpectedly, SF1 SOCS3 KO mice exhibited glucose intolerance during pregnancy. SF1 SOCS3 KO mice also presented a lower body weight (-3%; p < 0.05) during mid and late lactation, although food intake, litter size and offspring growth were not affected. Our findings suggest that increased leptin sensitivity in the VMH causes modest metabolic effects and is not sufficient to prevent major metabolic adaptations of pregnancy and lactation.
-
Parkinson's disease is a debilitating neurodegenerative movement disorder, characterized by the progressive and selective loss of dopaminergic neurons located in the substantia nigra, leading to clinical motor symptoms. The factors involved in PD are rather multifaceted. There are many cellular pathways contributing to its neuro-pathogenesis, which include abnormal protein aggregation, impaired ubiquitin proteasome system, autophagy, and neuroinflammation. ⋯ Since they somewhat modulate many mRNA targets simultaneously, many cellular pathways may be affected by one individual miRNA. Moreover, miRNAs can stably circulate in cerebrospinal fluid and blood, and their expression pattern can reflect the molecular pathophysiology, thus making them promising biomarkers in PD diagnosis and prognosis. In this review, we will review the recent progress on miRNA's mechanism in PD pathogenesis and discuss the possibilities of miRNAs as PD molecular biomarkers.
-
The capacity to identify unanticipated abnormal cues in a natural scene is vital for animal survival. Stimulus-specific adaptation (SSA) has been considered the neuronal correlate for deviance detection. There have been comprehensive assessments of SSA in the frequency domain along the ascending auditory pathway, but only little attention given to deviance detection in the spatial domain. ⋯ The variability in neuronal spatial discriminability among the TRN population was directly related to response difference (RD) but not variance; meanwhile, further analyses attributed higher spatial sensitivity at deviant locations to larger RD. Astonishingly, a significant correlation was found between the amount of adaptation and deviant discriminability. Collectively, our results suggest that adaptation facilitates rare location discrimination by sharpening the response gap between two locations.
-
Several diseases are characterized by cognitive instability, which is amplified in the conditions of sleep deprivation (SD). Cognitive instability in SD can be examined by the number of lapses on the psychomotor vigilance test (PVT), which is considered to be a gold standard in the field. However, the number of PVT lapses widely range according to inter-individual differences, from apparent cognitive resistance to severe cognitive impairment. ⋯ Our results showed significant negative correlations between numbers of PVT lapses and FA in multiple WM tracts, with the FA variations in the superior longitudinal fasciculus and splenium of the corpus callosum accounting for nearly 37.5% of individual variability in PVT lapses. In addition, dichotomized analyses indicated that the resilient participants exhibited significantly higher FA values compared with the vulnerable participants. Together, these findings suggest that cognitive instability after SD was closely associated with individual differences in WM integrity.