Neuroscience
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Many threats activate parabrachial neurons expressing calcitonin gene-related peptide (CGRPPBN) which transmit alarm signals to forebrain regions. Most CGRPPBN neurons also express tachykinin 1 (Tac1), but there are also Tac1-expressing neurons in the PBN that do not express CGRP (Tac1+;CGRP- neurons). ⋯ Activating Tac1+;CGRP- neurons, using an intersectional genetic targeting approach, resembles activating all Tac1PBN neurons. These results reveal that activation of Tac1+;CGRP- neurons can suppress some functions attributed to the CGRPPBN neurons, which provides a mechanism to bias behavioral responses to threats.
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The purpose of the study was to investigate the effect of isoflurane postconditioning on neuron injury in MCAO (middle cerebral artery occlusion) rats and its molecular mechanism of affecting autophagy through miR-384-5p/ATG5 (autophagy-related protein 5). HT22 cells (mouse hippocampal neuronal cell line) were exposed to 1.5% isoflurane for 30 min after OGD/R (oxygen-glucose deprivation/reoxygenation). Flow cytometry and CCK-8 kit were used to analyze changes in apoptosis and cell viability. ⋯ TUNEL staining and western blot results confirmed that isoflurane post-conditioning could regulate miR-384-5p and inhibit apoptosis. Immunofluorescence staining and western blot results confirmed that isoflurane post-conditioning inhibited autophagy in MCAO rats. Based on the above results, we speculated that the molecular mechanism of isoflurane post-conditioning to alleviate ischemic neuronal injury may be related to the regulation of miR-384-5p/ATG5-mediated autophagy.
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This study aimed to explore the neural mechanisms underlying food decision making in unsuccessful restrained eaters (US-REs) and successful restrained eaters (S-REs). During a functional magnetic resonance imaging scan, participants were required to choose between pairs of high- and low-calorie foods under the following conditions: the congruent condition (choose between high- and low-calorie foods with the same level of tastiness) and incongruent condition (choose between high-calorie foods tastier than the corresponding low-calorie foods). Subsequently, the participants' diets were monitored for one week. ⋯ Our results suggest that US-REs have a strong reward response to food. Compared to US-REs, S-REs are more guided more by the goal of weight control, and exhibit strong functional connections between the conflict-monitoring and inhibitory-control regions. Therefore, eating enjoyment and weight-control goals influence restrained eating in daily life.
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Physical activity (PA) has been shown to benefit various cognitive functions and promote neuroplasticity. Whereas the effects of PA on brain anatomy and function have been well documented in older individuals, data are scarce in young adults. Whether high levels of cardiorespiratory fitness (CRF) achieved through regular PA are associated with significant structural and functional changes in this age group remains largely unknown. ⋯ Transcranial magnetic stimulation (TMS) revealed higher corticospinal excitability in high- compared to low-fit individuals reflected by greater input/output curve amplitude and slope. No group differences were found for other TMS (short-interval intracortical inhibition and intracortical facilitation), diffusion MRI (fractional anisotropy and apparent fiber density), structural MRI (cortical thickness) and magnetic resonance spectroscopy (NAA, GABA, Glx) measures. Taken together, the present data suggest that brain changes associated with increased CRF are relatively limited, at least in primary motor cortex, in contrast to what has been observed in older adults.