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1.
Proc Natl Acad Sci U S A ; 117(6): 3239-3247, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-31992641

RESUMO

The olfactory system receives extensive serotonergic inputs from the dorsal raphe, a nucleus involved in control of behavior, regulation of mood, and modulation of sensory processing. Although many studies have investigated how serotonin modulates the olfactory bulb, few have focused on the anterior piriform cortex (aPC), a region important for olfactory learning and encoding of odor identity and intensity. Specifically, the mechanism and functional significance of serotonergic modulation of the aPC remain largely unknown. Here we used pharmacologic, optogenetic, and fiber photometry techniques to examine the serotonergic modulation of neural activity in the aPC in vitro and in vivo. We found that serotonin (5-HT) reduces the excitability of pyramidal neurons directly via 5-HT2C receptors, phospholipase C, and calcium-activated potassium (BK) channels. Furthermore, endogenous serotonin attenuates odor-evoked calcium responses in aPC pyramidal neurons. These findings identify the mechanism underlying serotonergic modulation of the aPC and shed light on its potential role.


Assuntos
Núcleo Dorsal da Rafe/metabolismo , Córtex Piriforme , Células Piramidais/metabolismo , Neurônios Serotoninérgicos/metabolismo , Serotonina/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Odorantes , Bulbo Olfatório/fisiologia , Optogenética , Córtex Piriforme/citologia , Córtex Piriforme/metabolismo , Serotonina/genética
2.
J Pharm Biomed Anal ; 240: 115947, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38181557

RESUMO

Huangqi Liuyi Decoction, a famous classical Chinese prescription, shows significant curative effect on diabetes and its complications, in which calycosin-7-glucoside, liquiritin and glycyrrhizic acid are the main components that playing these mentioned pharmacological activity, under the synergistic action of various other ingredients in the decoction. However, there are significant differences in the content of active compounds in Chinese medicinal materials, which mainly due to origin, picking seasons, and processing methods. Hence, the accurate content of the glycosides is the prerequisite for ensuring the pharmacological efficacy. Aiming at establishing an efficient extraction and determination method for accurate quantitative analysis of calycosin-7-glucoside, liquiritin and glycyrrhizic acid in Huangqi Liuyi Decoction, an on line solid-phase extraction-high-performance liquid chromatography method was developed, using a homemade bio-based monolithic adsorbent. The bio-based adsorbent was prepared in a stainless steel tube, using bio-monomers of methyleugenol and S-allyl-L-cysteine, which effectively reduced the dependence of the polymer field on non-renewable fossil resources and reduced carbon emissions. Furthermore, the prepared adsorbent owned abundant chemical groups, which can produce interactions of hydrogen bond, dipole-dipole, π-π and hydrophobic force with the target glycosides, thus improving the specific recognition ability of the adsorbent. The experiments were carried out on an LC-3000 HPLC instrument with a six-way valve. Methodology validation indicates that the recovery is in the range of 97.0%-103.4% with the RSD in the range of 1.6%-4.0%, due to the specific selectivity of the bio-based monolithic adsorbent for these three glycosides, and good matrix-removal ability for Huangqi Liuyi decoction. The limit of detection is 0.17, 0.50 and 0.33 µg/mL for calycosin-7-glucoside, liquiritin and glycyrrhizic acid, respectively, and the limit of quantitation is 0.50, 1.50 and 1.00 µg/mL, respectively, with the linear range of 2-200 µg/mL for calycosin-7-glucoside, and 5-500 µg/mL for liquiritin and glycyrrhizic acid. The present work provided a simple and efficient method for the extraction and determination of glycosides in complex medicinal plants.


Assuntos
Astragalus propinquus , Medicamentos de Ervas Chinesas , Glicosídeos , Polímeros/análise , Ácido Glicirrízico , Medicamentos de Ervas Chinesas/química , Glucosídeos/análise , Cromatografia Líquida de Alta Pressão/métodos
3.
Acta Physiol (Oxf) ; 240(9): e14198, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38958443

RESUMO

AIM: Neural activity in the olfactory bulb (OB) can represent odor information during different brain and behavioral states. For example, the odor responses of mitral/tufted (M/T) cells in the OB change during learning of odor-discrimination tasks and, at the network level, beta power increases and the high gamma (HG) power decreases during odor presentation in such tasks. However, the neural mechanisms underlying these observations remain poorly understood. Here, we investigate whether serotonergic modulation from the dorsal raphe nucleus (DRN) to the OB is involved in shaping activity during the learning process in a go/no-go task in mice. METHODS: Fiber photometry was used to record the population activity of DRN serotonergic neurons during a go/no-go task. In vivo electrophysiology was used to record neural activity (single units and local field potentials) in the OB during the go/no-go task. Real-time place preference (RTPP) and intracranial light administration in a specific subarea (iClass) tests were used to assess the ability of mice to encoding reward information. RESULTS: Odor-evoked population activity in serotonergic neurons in the DRN was shaped during the learning process in a go/no-go task. In the OB, neural activity from oscillations to single cells showed complex, learning-associated changes and ability to encode information during an odor discrimination task. However, these properties were not observed after ablation of DRN serotonergic neurons. CONCLUSION: The activity of neural networks and single cells in the OB, and their ability to encode information about odor value, are shaped by serotonergic projections from the DRN.


Assuntos
Núcleo Dorsal da Rafe , Odorantes , Bulbo Olfatório , Neurônios Serotoninérgicos , Animais , Bulbo Olfatório/fisiologia , Núcleo Dorsal da Rafe/fisiologia , Núcleo Dorsal da Rafe/metabolismo , Camundongos , Masculino , Neurônios Serotoninérgicos/fisiologia , Camundongos Endogâmicos C57BL , Aprendizagem/fisiologia , Serotonina/metabolismo , Olfato/fisiologia
4.
Brain Res Bull ; 217: 111079, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39270805

RESUMO

Generalized fear is a maladaptive behavior in which non-threatening stimuli elicit a fearful response. The ventral tegmental area (VTA) has been demonstrated to play important roles in fear response and fear memory generalization, but the precious neural circuit mechanism is still unclear. Here, we demonstrated that VTA-zona incerta (ZI) glutamatergic projection is involved in regulating high-intensity threatening training induced generalization and anxiety. Combining calcium signal recording and chemogentics, our work reveals that VTA glutamatergic neurons respond to closed arm entering in the model of PTSD. Inhibition of VTA glutamatergic neurons or the glutamatergic projection to ZI could both relieve fear generalization and anxiety. Together, our study proves the VTA - ZI glutamatergic circuit is involved in mediating fear generalization and anxiety, and provides a potential target for treating post-traumatic stress disorder.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38666348

RESUMO

While hydrometallurgy is the primary technology for recycling spent lithium-ion batteries due to various advantages, it still involves substantial consumption of chemical reagents and poses challenges in wastewater emission. Herein, we report the realization of cathode recycling under lean-leachate conditions by dynamically stabilizing hole-mediated diffusion kinetics, which is enabled by synchronizing the extraction step during the leaching stage, thus continuously removing the dissolved ions out of the leachate. Theoretical molecular dynamics simulations predict that preventing the accumulation of the dissolved ions is efficient for keeping the leaching process proceeding. Experimentally, even with a small dosage of leachate (0.5 mL), a 94.51% leaching efficiency can be achieved (90 °C, 40 min) for spent LNO materials. Considering that our strategy is not limited to a specific materials system, it could be extended to recycle other valuable materials (including LCO or NCM 811) with minimal leachate usage.

6.
Adv Sci (Weinh) ; 11(29): e2401635, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38828658

RESUMO

The low mechanical reliability and integration failure are key challenges hindering the commercialization of geometrically flexible batteries. This work proposes that the failure of directly integrating flexible batteries using traditional rigid adhesives is primarily due to the mismatch between the generated stress at the adhesive/substrate interface, and the maximum allowable stress. Accordingly, a stress redistribution adhesive layer (SRAL) strategy is conceived by using elastic adhesive to redistribute the generated stress. The function mechanism of the SRAL strategy is confirmed by theoretical finite element analysis. Experimentally, a polyurethane (PU) type elastic adhesive (with maximum strain of 1425%) is synthesized and used as the SRAL to integrate rigid cells on different flexible substrates to fabricate directly integrated flexible battery with robust output under various harsh environments, such as stretching, twisting, and even bending in water. The SRAL strategy is expected to be generally applicable in various flexible devices that involve the integration of rigid components onto flexible substrates.

7.
Neuropharmacology ; 257: 110034, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38878858

RESUMO

Clinical surgery can lead to severe neuroinflammation and cognitive dysfunctions. It has been reported that astrocytes mediate memory formation and postoperative cognitive dysfunction (POCD), however, the thalamic mechanism of astrocytes in mediating POCD remains unknown. Here, we report that reactive astrocytes in zona incerta (ZI) mediate surgery-induced recognition memory impairment in male mice. Immunostaining results showed that astrocytes are activated with GABA transporter-3 (GAT-3) being down-expressed, and neurons were suppressed in the ZI. Besides, our work revealed that reactive astrocytes caused increased tonic current in ZI neurons. Up-regulating the expression of GAT-3 in astrocytes ameliorates surgery-induced recognition memory impairment. Together, our work demonstrates that the reactive astrocytes in the ZI play a crucial role in surgery-induced memory impairment, which provides a new target for the treatment of surgery-induced neural dysfunctions.


Assuntos
Astrócitos , Proteínas da Membrana Plasmática de Transporte de GABA , Transtornos da Memória , Regulação para Cima , Zona Incerta , Animais , Masculino , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Transtornos da Memória/metabolismo , Camundongos , Regulação para Cima/efeitos dos fármacos , Astrócitos/metabolismo , Zona Incerta/metabolismo , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Complicações Cognitivas Pós-Operatórias/metabolismo , Complicações Cognitivas Pós-Operatórias/prevenção & controle , Reconhecimento Psicológico/efeitos dos fármacos , Reconhecimento Psicológico/fisiologia
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