Brain research
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Trigeminal motoneurons (MNs) innervating the jaw-closing and jaw-opening muscles receive numerous inhibitory synaptic inputs from GABAergic and glycinergic neurons, which are essential for oromotor functions, such as the orofacial reflex, suckling, and mastication. The properties of the GABAergic and glycinergic inputs of these MNs undergo developmental alterations during the period in which their feeding behavior proceeds from suckling to mastication; however, the detailed characteristics of the developmental patterns of GABAergic and glycinergic transmission in these neurons remain to be elucidated. This study was conducted to investigate developmental changes in miniature inhibitory postsynaptic currents (mIPSCs) in masseter (jaw-closing) and digastric (jaw-opening) MNs using brainstem slice preparations obtained from Wistar rats on postnatal day (P)2-5, P9-12, and P14-17. ⋯ The proportion of currents mediated by GABA-glycine co-transmission was higher at P2-5, and then it decreased with age in both MNs. These results suggest that characteristics related to the development of inhibitory synaptic inputs differ between jaw-closing and jaw-opening MNs and between GABAergic and glycinergic currents. These distinct developmental characteristics may contribute to the development of feeding behaviors.
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Quercetin is a flavonoid compound rich in many natural plants with a wide range of pharmacological effects and nutritional value. Although previous studies have initially shown the antidepressant effect of quercetin in some models. However, the exact mechanism of the antidepressant effect of quercetin on the depression model induced by chronic unpredictable mild stress (CUMS) is still unclear or has not been clearly elucidated. ⋯ In addition, CUMS also caused significant reduction in the levels of antioxidants including superoxide dismutase (SOD) and glutathione-s transferase (GST) in the mice hippocampus by 51.3%, 40.3% (both P < 0.01), while after chronic oral administration of high dose quercetin at 40 mg/kg, the abnormalities of the above indicators were significantly reversed by 69.2% and 49.5% (both P < 0.01), as well as significant elevation in the levels of lipid peroxide malondialdehyde (MDA), inflammation medium nitric oxide (NO) and inducible nitric oxide synthase (iNOS) by 156.4%, 255.4% and 72.7% (all P < 0.01), while after chronic oral administration of high dose quercetin at 40 mg/kg, the abnormalities of the above indicators were significantly reversed by 45.9%, 26.8% and 55.2% (all P < 0.01). The medium dose of quercetin (20 mg/kg) only reversed some of the above indicators, while the low dose of quercetin (10 mg/kg) had no reversal effect on the above indicators. Collectively, the present study confirmed for the first time that quercetin weakened CUMS-induced depression in vivo, and its mechanism was at least partially attributable to the upregulation of hippocampal Nrf2 and the inhibition of iNOS, thereby correcting the central inflammatory response, and the imbalance between oxidation and antioxidant.
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Most of our decisions involve a certain degree of risk regarding the outcomes of our choices. People vary in the way they make decisions, resulting in different levels of risk-taking behavior. These differences have been linked to prefrontal theta band activity. However, a direct functional relationship between prefrontal theta band activity and risk-taking has not yet been demonstrated. ⋯ These findings provide direct empirical evidence for the effects of prefrontal theta band stimulation on behavioral risk-taking regulation.
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Comparative Study
A direct comparison of the electrophysiological effects of transcranial direct and alternating current stimulation in healthy subjects.
Despite the clinical effectiveness of transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS), the comparability of these interventions in neurophysiological aspects have not been thoroughly investigated. Thus, we aimed to directly compare the electrophysiological effects of single-session tDCS and gamma-tACS in healthy subjects, matching the intervention protocol as closely as possible. ⋯ The present study indicates that tDCS and tACS resulted in an increased range of frequency activity, including slow- and fast-wave bands. Specifically, tDCS modulates the frontal region, while tACS modulates neural oscillations at the fronto-central, parietal, and temporal areas. The tACS also decreased low-beta source activity in the middle temporal gyrus. Identifying the common and unique EEG patterns of tDCS and tACS may help shed light on their potential clinical benefits and distinctive neuropathology in various clinical symptoms.
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Valproate (VPA) is capable of attenuating ischemic stroke (IS)-related disorders in brain tissues. Long non-coding RNAs (lncRNAs) are involved in the progression of IS. In the current study, the role of lncRNA RMRP in the protective effects of VPA against IS was explored. ⋯ Moreover, the induced expression of RMRP blocked the anti-OGD function of VPA, indicating the key role of RMRP inhibition in the effects of VPA on nerve system. Collectively, VPA attenuated MCAO/OGD-induced disorders in mice and microglia. The effects were dependent on the inhibition of RMRP, which subsequently induced the activation of PI3K/Akt signaling.