Neuroscience
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We compared the efficacy of a modified truncated 24-aa peptide (TFP5), derived from the cyclin-dependent kinase 5 (CDK5)-activating cofactor p35, with mild hypothermia (MH), and determined whether the efficacy of TFP5 is affected by MH. ⋯ TFP5 is comparable to MH in improving neurological outcomes in early-stage adult ischemic stroke. When TFP5 is given along with MH, less neurological deficit tends to be achieved.
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Decreased proteolytic clearance of soluble amyloid β (Aβ) in microglia affects Aβ accumulation on Alzheimer's disease progression. However, the potential molecular mechanism by which microglial Aβ uptake is regulated remains unclear. In this study, we identified a microRNA, miR-124, that was down-regulated in aging with a function in regulating apolipoprotein E (ApoE)-dependent Aβ uptake by targeting regulatory factor X1 (RFX1) transcripts on BV2 microglia cell. ⋯ We also identified a miR-124 binding site in the 3'-UTR of RFX1 mRNA and a RFX1 binding site in the first intron of ApoE gene. Furthermore, interfering this signaling pathway by knocking down RFX1 significantly improved Aβ uptake in BV2 cells. These data demonstrate the mechanism through which decreased miR-124 expression under oxidative stress slowed Aβ uptake and suggest that RFX1 might be a target for improving Aβ clearance during aging.
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Transcranial direct current stimulation (tDCS) is a common method to modulate cortical activity. Anodal tDCS is usually associated with an enhancement of the stimulated brain area, whereas cathodal tDCS is often described as inhibitory brain stimulation method. Our aim was to investigate whether this canonical assumption derived from the motor system could be transferred to the semantic system. ⋯ Recently, a meta-analysis revealed that the canonical anodal excitation and cathodal inhibition assumption is observed rarely in cognitive studies. In particular, an inhibitory effect of cathodal tDCS on cognition is rare. Our findings thus support the speculation, that especially language functions could be somewhat 'immune' to cathodal inhibition.
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The aging process and menopausal transition are important factors in sexual dysfunction of menopausal women. No neuroimaging study has assessed the age- and menopause-related changes on brain activation areas associated with sexual arousal in menopausal women. The purpose of this study was to evaluate the time course of regional brain activity associated with sexual arousal evoked by visual stimulation in premenopausal and menopausal women, and further to assess the effect of menopause on the brain areas associated with sexual arousal in menopausal women using functional magnetic resonance imaging (fMRI). ⋯ Blood-oxygen-level-dependent signal changes in the amygdala while viewing erotic video were positively correlated with estrogen levels in the two groups. Our findings suggest that reduced brain activity of the thalamus, amygdala, and ACC in menopausal women may be associated with menopause-related decrease in sexual arousal. These findings might help elucidate the neural mechanisms associated with sexual dysfunction in menopausal women.
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The hypothalamic-pituitary-adrenal (HPA) axis undergoes critical developments during adolescence. Therefore, stressors experienced during this period potentially have long-term effects on adult HPA axis function. We hypothesized that adolescent intermittent ethanol (AIE) exposure would affect adult HPA axis function, resulting in altered responses to an alcohol challenge in young adults or adults. ⋯ Results of the present study are similar to what we have previously shown, that these changes in PVN responsiveness may result from AIE-induced alterations in adrenergic neurons in brain stem regions C1-C3 known to project to the PVN. AIE elevated the number of colocalized c-fos/phenylethanolamine N-methyltransferase (PNMT)-positive cell bodies in the C1 region of adult rats. Together, these data suggest that AIE exposure produces alterations in male HPA axis responsiveness to administration of an acute alcohol challenge that may be long-lasting.