Neuroscience
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Neuroinflammation is proposed to be an important component in the development of several central nervous system (CNS) disorders including depression, Alzheimer's disease, Parkinson's disease, and traumatic brain injury. However, exactly how neuroinflammation leads to, or contributes to, these central disorders is unclear. The objective of the study was to examine and compare the expression of mRNAs for interleukin-6 (IL-6), IL-7, IL-10 and the receptors for IL-6 (IL-6R) and IL-7 (IL-7R) using in situ hybridization in discrete brain regions and in the spleen after multiple injections of 3mg/kg lipopolysaccharide (LPS), a model of neuroinflammation. ⋯ These studies indicate that LPS-induced neuroinflammation has substantial but variable effects on the regional and cellular patterns of CNS IL-6, IL-7 and IL-10, and for IL-6R and IL-7R mRNA expression. It is apparent that administration of LPS can affect non-neuronal and neuronal cells in the brain. Further research is required to determine how CNS inflammatory changes associated with IL-6, IL-10 and IL-6R could in turn contribute to the development of CNS neurological disorders.
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The somatosensory information from the orofacial region, including the periodontal ligament (PDL), is processed in a manner that differs from that used for other body somatosensory information in the related cortices. It was reported that electrical stimulation to rat PDL elicited activation of the insular oral region (IOR) and the primary (S1) and secondary (S2) somatosensory cortices. However, the physiological relationship between S1 and S2/IOR is not well understood. ⋯ An injection of FluoroGold™ (FG) to the initial response area in S1 or the S2/IOR showed that FG-positive cells were scattered in the non-injected cortical counterpart. This morphological result demonstrated the presence of a bi-directional intracortical connection between the initial response areas in S1 and the S2/IOR. These findings suggest the presence of a mutual connection between S1 and the S2/IOR as an intracortical signal processing network for orofacial nociception.
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Chitinase activity is increased in Alzheimer's disease (AD). However, the role of chitinase1 in AD is unknown. We investigated the effects of chitinase1 on Alzheimer's pathology and microglia function. ⋯ A higher level of M2 markers (Arg-1, MRC1/CD206) and a lower level of classic M1 markers (TNFa, IL-1β) were obtained in Aβ-pretreated N9 cells with chitinase1, suggesting that chitinase1 polarized the microglia into an anti-AD M2 phenotype. We also detected that chitnase1 could weaken the deposition of Aβ oligomers in the brain of D-galactose/ AlCl3-induced AD rats. In conclusion, Chitinase1 might exert protective effects against AD by polarizing microglia to an M2 phenotype and resisting Aβ oligomer deposition.
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Chess involves the capacity to reason iteratively about potential intentional choices of an opponent and therefore involves high levels of explicit theory of mind [ToM] (i.e. ability to infer mental states of others) alongside clear, strategic rule-based decision-making. Functional magnetic resonance imaging was used on 12 healthy male novice chess players to identify cortical regions associated with chess, ToM and empathizing. The blood-oxygenation-level-dependent (BOLD) response for chess and empathizing tasks was extracted from each ToM region. ⋯ Results support previous findings, that ToM recruits a neural network with each region sub-serving a supporting role depending on the nature of the task itself. In contrast, a network of cortical regions primarily located within right- and left-hemisphere medial-frontal and parietal cortex, outside the internal representational network, was selectively recruited during the chess task. We hypothesize that in our cohort of novice chess players the strategy was to employ an iterative thinking pattern which in part involved mentalizing processes and recruited core ToM-related regions.
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Perineuronal nets (PNNs) are structures of extracellular matrix molecules surrounding the cell bodies and proximal dendrites of certain neurons. While PNNs are present throughout the mouse cerebral cortex, recent studies have shown that the components differ among cortical sub-regions and layers, suggesting region-specific functions. Parvalbumin-expressing interneurons (PV neurons) may be important regulators of cortical plasticity during the early "critical period" that is sensitive to sensory input. ⋯ These WFA(+) PNNs changed from granular-like to reticular-like structures during normal cortical development, while this transition was delayed by sensory deprivation. This study indicates that the formation of reticular-like WFA(+) PNNs is dependent on sensory experience in the mouse somatosensory cortex. We suggest that Cat-315(+) molecules and WFA expression in PNNs are involved in the early critical period of input-dependent cortical plasticity.