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1.
Nat Commun ; 15(1): 4347, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773146

RESUMO

Epigenetic mechanisms bridge genetic and environmental factors that contribute to the pathogenesis of major depression disorder (MDD). However, the cellular specificity and sensitivity of environmental stress on brain epitranscriptomics and its impact on depression remain unclear. Here, we found that ALKBH5, an RNA demethylase of N6-methyladenosine (m6A), was increased in MDD patients' blood and depression models. ALKBH5 in astrocytes was more sensitive to stress than that in neurons and endothelial cells. Selective deletion of ALKBH5 in astrocytes, but not in neurons and endothelial cells, produced antidepressant-like behaviors. Astrocytic ALKBH5 in the mPFC regulated depression-related behaviors bidirectionally. Meanwhile, ALKBH5 modulated glutamate transporter-1 (GLT-1) m6A modification and increased the expression of GLT-1 in astrocytes. ALKBH5 astrocyte-specific knockout preserved stress-induced disruption of glutamatergic synaptic transmission, neuronal atrophy and defective Ca2+ activity. Moreover, enhanced m6A modification with S-adenosylmethionine (SAMe) produced antidepressant-like effects. Our findings indicate that astrocytic epitranscriptomics contribute to depressive-like behaviors and that astrocytic ALKBH5 may be a therapeutic target for depression.


Assuntos
Homólogo AlkB 5 da RNA Desmetilase , Astrócitos , Transtorno Depressivo Maior , Camundongos Knockout , Animais , Astrócitos/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/genética , Camundongos , Humanos , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/patologia , Masculino , Feminino , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Estresse Psicológico/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Transportador 2 de Aminoácido Excitatório/genética , Comportamento Animal , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Depressão/metabolismo , Depressão/genética , Adulto , Transmissão Sináptica , Pessoa de Meia-Idade
2.
J Environ Manage ; 347: 119189, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37793293

RESUMO

Agricultural production consumes the majority of global freshwater resources. The worsening water scarcity has imposed significant stress on agricultural production when regions seek food self-sufficiency. To seek optimal allocation of spatial agricultural water and land resources in each water function zone of the objective region, a multi-objective optimization model was developed to tackle the trade-offs between the water-saving objective and the economic benefit objective considering virtual water trade (VWT). The cultivated area of each crop in each water function zone was taken into account as the decision variable, while a set of strong constraints were used to restrict land resources and water availability. Then, a decomposition-simplex method aggregation algorithm (DSMA) was proposed to solve this nonlinear, bounding-constrained, and multi-objective optimization model. Based on the quantitative analysis of the spatial blue and green virtual water in each agricultural product, the proposed methodology was applied to a real-world, provincial-scale region in China (i.e., Jiangsu Province). The optimized results provided 18 Pareto solutions to reallocate the land resources in the 21 IV-level water function zones of Jiangsu Province, considering four major rainy-season crops and two dry-season crops. Compared to the actual scenario, the superior scheme increased by 7.95% (5.6 × 109 RMB) for economic trade and decreased by 1.77% (2.0 × 109 m3) for agricultural water consumption. It was mainly because the potential of spatial blue and green virtual water in Jiangsu was fully exploited by improving spatial land resource allocation. The food security of Jiangsu could be guaranteed by achieving self-sufficiency in the superior scheme, and the total VWT in the optimal scheme was 2.2 times more than the actual scenario. The results provided a systematic decision-support methodology from the perspective of spatial virtual water coordination, yet, the methodology is widely applicable.


Assuntos
Conservação dos Recursos Naturais , Água , Conservação dos Recursos Naturais/métodos , Agricultura/métodos , Abastecimento de Água , Recursos Hídricos , China
3.
Carcinogenesis ; 44(8-9): 682-694, 2023 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-37294054

RESUMO

EphB6 belongs to the receptor tyrosine kinase, whose low expression is associated with shorter survival of colorectal cancer (CRC) patients. But the role and mechanism of EphB6 in the progression of CRC need further study. In addition, EphB6 was mainly expressed in intestinal neurons. But how EphB6 is involved in functions of intestinal neurons has not been known. In our study, we constructed a mouse xenograft model of CRC by injecting CMT93 cells into the rectum of EphB6-deficient mice. We found that the deletion of EphB6 in mice promoted tumor growth of CMT93 cells in a xenograft model of CRC, which was independent of changes in the gut microbiota. Interestingly, inhibition of intestinal neurons by injecting botulinum toxin A into rectum of EphB6-deficient mice could eliminate the promotive effect of EphB6 deficiency on tumor growth in the xenograft model of CRC. Mechanically, the deletion of EphB6 in mice promoted the tumor growth in CRC by increasing GABA in the tumor microenvironment. Furthermore, EphB6 deficiency in mice increased the expression of synaptosomal-associated protein 25 in the intestinal myenteric plexus, which mediated the release of GABA. Our study concluded that EphB6 knockout in mice promotes tumor growth of CMT93 cells in a xenograft model of CRC by modulating GABA release. Our study found a new regulating mechanism of EphB6 on the tumor progression in CRC that is dependent on intestinal neurons.


Assuntos
Comunicação Celular , Neoplasias Colorretais , Humanos , Animais , Camundongos , Neoplasias Colorretais/metabolismo , Intestinos/patologia , Neurônios/metabolismo , Neurônios/patologia , Ácido gama-Aminobutírico , Microambiente Tumoral
4.
J Agric Food Chem ; 71(12): 4769-4788, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36930583

RESUMO

Hippophae rhamnoides L. (sea buckthorn), consumed as a food and health supplement worldwide, has rich nutritional and medicinal properties. Different parts of H. rhamnoides L. were used in traditional Chinese medicines for relieving cough, aiding digestion, invigorating blood circulation, and alleviating pain since ancient times. Phytochemical studies revealed a wide variety of phytonutrients, including nutritional components (proteins, minerals, vitamins, etc.) and functional components like flavonoids (1-99), lignans (100-143), volatile oils (144-207), tannins (208-230), terpenoids (231-260), steroids (261-270), organic acids (271-297), and alkaloids (298-305). The pharmacological studies revealed that some crude extracts or compounds of H. rhamnoides L. demonstrated various health benefits, such as anti-inflammatory, antioxidant, hepatoprotective, anticardiovascular disease, anticancer, hypoglycemic, hypolipidemic, neuroprotective, antibacterial activities, and their effective doses and experimental models were summarized and analyzed in this paper. The quality markers (Q-markers) of H. rhamnoides L. were predicted and analyzed based on protobotanical phylogeny, traditional medicinal properties, expanded efficacy, pharmacokinetics and metabolism, and component testability. The applications of H. rhamnoides L. in juice, wine, oil, ferment, and yogurt were also summarized and future prospects were examined in this review. However, the mechanism and structure-activity relationship of some active compounds are not clear, and quality control and potential toxicity are worth further study in the future.


Assuntos
Botânica , Hippophae , Óleos Voláteis , Hippophae/química , Compostos Fitoquímicos/farmacologia , Antioxidantes
5.
Neuropsychopharmacology ; 48(8): 1164-1174, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36797374

RESUMO

Pharmacological manipulation of mGluR5 has showed that mGluR5 is implicated in the pathophysiology of anxiety and mGluR5 has been proposed as a potential drug target for anxiety disorders. Nevertheless, the mechanism underlying the mGluR5 involvement in stress-induced anxiety-like behavior remains largely unknown. Here, we found that chronic restraint stress induced anxiety-like behavior and decreased the expression of mGluR5 in hippocampal CA1. Specific knockdown of mGluR5 in hippocampal CA1 pyramidal neurons produced anxiety-like behavior. Furthermore, both chronic restraint stress and mGluR5 knockdown impaired inhibitory synaptic inputs in hippocampal CA1 pyramidal neurons. Notably, positive allosteric modulator of mGluR5 rescued stress-induced anxiety-like behavior and restored the inhibitory synaptic inputs. These findings point to an essential role for mGluR5 in hippocampal CA1 pyramidal neurons in mediating stress-induced anxiety-like behavior.


Assuntos
Hipocampo , Células Piramidais , Hipocampo/metabolismo , Células Piramidais/fisiologia , Ansiedade/tratamento farmacológico , Região CA1 Hipocampal
6.
J Clin Invest ; 133(7)2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36757814

RESUMO

Major depressive disorder is a common and devastating psychiatric disease, and the prevalence and burden are substantially increasing worldwide. Multiple studies of depression patients have implicated glucose metabolic dysfunction in the pathophysiology of depression. However, the molecular mechanisms by which glucose and related metabolic pathways modulate depressive-like behaviors are largely uncharacterized. Uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) is a glucose metabolite with pivotal functions as a donor molecule for O-GlcNAcylation. O-GlcNAc transferase (OGT), a key enzyme in protein O-GlcNAcylation, catalyzes protein posttranslational modification by O-GlcNAc and acts as a stress sensor. Here, we show that Ogt mRNA was increased in depression patients and that astroglial OGT expression was specifically upregulated in the medial prefrontal cortex (mPFC) of susceptible mice after chronic social-defeat stress. The selective deletion of astrocytic OGT resulted in antidepressant-like effects, and moreover, astrocytic OGT in the mPFC bidirectionally regulated vulnerability to social stress. Furthermore, OGT modulated glutamatergic synaptic transmission through O-GlcNAcylation of glutamate transporter-1 (GLT-1) in astrocytes. OGT astrocyte-specific knockout preserved the neuronal morphology atrophy and Ca2+ activity deficits caused by chronic stress and resulted in antidepressant effects. Our study reveals that astrocytic OGT in the mPFC regulates depressive-like behaviors through the O-GlcNAcylation of GLT-1 and could be a potential target for antidepressants.


Assuntos
Astrócitos , Transtorno Depressivo Maior , Camundongos , Animais , Astrócitos/metabolismo , Depressão/genética , Transmissão Sináptica , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Antidepressivos , Glucose , Acetilglucosamina/metabolismo
7.
Nat Prod Res ; 37(4): 551-559, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35574640

RESUMO

Three new compounds, 4,5,6,7-tetramethoxy-3-benzoylbenzofuran (1), 4-hydroxy-3,5,6-trimethoxydihydrochalcone-2-O-ß-D-glucopyranoside (2) and 2-hydroxy-3,4,5,6-tetramethoxyphenylethyl benzoate (3) along with five known flavonoids were isolated from the dichloromethane fraction of the stems of Fissistigma acuminatissimum Merr.'s ethanol extracts. The compounds were obtained by chromatographic methods and the structure elucidation was completed primarily on the basis of spectroscopic analyses, all of these compounds were isolated from F. acuminatissimum for the first time. All the fractions and compounds were evaluated for their anti-inflammatory activity against lipopolysaccharide (LPS)-stimulated tumor necrosis factor α (TNF-α) production in RAW264.7 cells in vitro. The dichloromethane fraction showed the most potent inhibition(38.2%) at 60 µg/mL, compound 1 (70.2%) and 3 (65.2%) showed significant inhibition at 10 µM.


Assuntos
Annonaceae , Annonaceae/química , Cloreto de Metileno , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Flavonoides/farmacologia , Flavonoides/química
9.
J Clin Biochem Nutr ; 71(3): 238-244, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36447492

RESUMO

The relationship between folic acid and S-adenosylhomocysteine (SAH) is controversial. This study aims to explore the effect of different doses of folic acid supplementation on SAH levels in hypertensive patients and the modification of methylene-tetrahydrofolate reductase (MTHFR) C677T gene polymorphism. A randomized, double-blind, controlled clinical trial was conducted. Hypertensive patients aged 45-75 years without a history of stroke and cardiovascular disease were selected, who were randomly assigned to one of 8 dose groups. This trial has been registered with Trial Number: ChiCTR1800016135. In the total population, folic acid supplementation of 0.4-2.0 mg/day had no effect on SAH level (ß = 0.47, 95% CI: -0.86-1.79, p = 0.491), while folic acid supplementation of 2.4 mg/day significantly increased SAH level (ß = 1.93, 95% CI: 0.22-3.64, p = 0.027). Stratified analysis found that MTHFR C677T genotype CC supplemented with 2.4 mg/day folic acid had no effect on SAH level (ß = 0.30, 95% CI: -2.74-3.34, p = 0.847), while CT and TT genotype supplemented with 2.4 mg/day folic acid showed a significant increase in SAH level (CT: ß = 2.98, 95% CI: 0.34-5.62, p = 0.027; TT: ß = 3.00, 95% CI: -0.51-6.51, p = 0.095; CT combined with TT: ß = 2.99, 95% CI: 0.90-5.09, p = 0.005). In conclusion, supplementation of 2.4 mg/day folic acid can lead to increased SAH levels, especially in MTHFR C677T genotype CT and TT.

10.
Cell Death Dis ; 13(10): 893, 2022 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273194

RESUMO

Noninflammatory clearance of dying cells by professional phagocytes, termed efferocytosis, is fundamental in both homeostasis and inflammatory fibrosis disease but has not been confirmed to occur in chronic pancreatitis (CP). Here, we investigated whether efferocytosis constitutes a novel regulatory target in CP and its mechanisms. PRSS1 transgenic (PRSS1Tg) mice were treated with caerulein to mimic CP development. Phospholipid metabolite profiling and epigenetic assays were performed with PRSS1Tg CP models. The potential functions of Atp8b1 in CP model were clarified using Atp8b1-overexpressing adeno-associated virus, immunofluorescence, enzyme-linked immunosorbent assay(ELISA), and lipid metabolomic approaches. ATAC-seq combined with RNA-seq was then used to identify transcription factors binding to the Atp8b1 promoter, and ChIP-qPCR and luciferase assays were used to confirm that the identified transcription factor bound to the Atp8b1 promoter, and to identify the specific binding site. Flow cytometry was performed to analyze the proportion of pancreatic macrophages. Decreased efferocytosis with aggravated inflammation was identified in CP. The lysophosphatidylcholine (LPC) pathway was the most obviously dysregulated phospholipid pathway, and LPC and Atp8b1 expression gradually decreased during CP development. H3K27me3 ChIP-seq showed that increased Atp8b1 promoter methylation led to transcriptional inhibition. Atp8b1 complementation substantially increased the LPC concentration and improved CP outcomes. Bhlha15 was identified as a transcription factor that binds to the Atp8b1 promoter and regulates phospholipid metabolism. Our study indicates that the acinar Atp8b1/LPC pathway acts as an important "find-me" signal for macrophages and plays a protective role in CP, with Atp8b1 transcription promoted by the acinar cell-specific transcription factor Bhlha15. Bhlha15, Atp8b1, and LPC could be clinically translated into valuable therapeutic targets to overcome the limitations of current CP therapies.


Assuntos
Adenosina Trifosfatases , Lisofosfatidilcolinas , Macrófagos , Pancreatite Crônica , Animais , Camundongos , Células Acinares/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Ceruletídeo/toxicidade , Histonas/metabolismo , Inflamação/metabolismo , Lisofosfatidilcolinas/genética , Lisofosfatidilcolinas/metabolismo , Macrófagos/metabolismo , Pancreatite Crônica/induzido quimicamente , Pancreatite Crônica/genética , Pancreatite Crônica/metabolismo , Proteínas de Transferência de Fosfolipídeos/genética , Proteínas de Transferência de Fosfolipídeos/metabolismo , Fatores de Transcrição/metabolismo
11.
Theranostics ; 12(8): 3703-3718, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35664080

RESUMO

Rationale: Stress is a major risk factor for the development of depression. However, the underlying molecular mechanisms of stress vulnerability in depression are largely uncharacterized. Methods: P2X2 receptors (a major receptor for gliotransmitter-ATP) in the medial prefrontal cortex (mPFC) were identified by real-time qPCR, western blots and RNAscope in situ hybridization in chronic social defeat stress model (CSDS). We generated P2X2 conditional knockout mice and overexpressed AAV-P2X2 in CamkIIα-Cre mice. The depression-like behaviors were assessed via CSDS, subthreshold social defeat stress (SSDS), social interaction test (SI), forced interaction test (FIT), forced swimming test (FST), sucrose preference test (SPT), novel stressed feeding (NSF) and open field test (OFT). The neuronal activity and synapse function of P2X2 receptors in the mPFC were detected by in vivo fiber-photometry, patch-clamp techniques and neuronal morphometric analysis. Results: We identified that P2X2 receptors were increased in the mPFC of susceptible mice in CSDS. Conditional knockout of P2X2 receptors in pyramidal neurons promoted resilience of chronic stress-induced depressive-like behaviors, whereas pyramidal neurons - specific gain of P2X2 in the mPFC increased vulnerability to depressive-like behaviors. In vivo fiber-photometry, electrophysiology and neuronal morphometric analysis showed P2X2 receptors regulated neuronal activity and synapse function in the mPFC. Conclusions: Overall, our studies reveal a critical role of P2X2 in mediating vulnerability to chronic stress and identify P2X2 as a potential therapeutic target for treatment of stress-related mood disorders.


Assuntos
Células Piramidais , Estresse Psicológico , Animais , Camundongos , Camundongos Endogâmicos C57BL , Neurônios , Receptores Purinérgicos P2X2
12.
J Transl Med ; 20(1): 218, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562743

RESUMO

BACKGROUND: Early diagnosis and treatment of chronic pancreatitis (CP) are limited. In this study, St13, a co-chaperone protein, was investigated whether it constituted a novel regulatory target in CP. Meanwhile, we evaluated the value of micro-PET/CT in the early diagnosis of CP. METHODS: Data from healthy control individuals and patients with alcoholic CP (ACP) or non-ACP (nACP) were analysed. PRSS1 transgenic mice (PRSS1Tg) were treated with ethanol or caerulein to mimic the development of ACP or nACP, respectively. Pancreatic lipid metabolite profiling was performed in human and PRSS1Tg model mice. The potential functions of St13 were investigated by crossing PRSS1Tg mice with St13-/- mice via immunoprecipitation and lipid metabolomics. Micro-PET/CT was performed to evaluate pancreatic morphology and fibrosis in CP model. RESULTS: The arachidonic acid (AA) pathway ranked the most commonly dysregulated lipid pathway in ACP and nACP in human and mice. Knockout of St13 exacerbated fatty replacement and fibrosis in CP model. Sdf2l1 was identified as a binding partner of St13 as it stabilizes the IRE1α-XBP1s signalling pathway, which regulates COX-2, an important component in AA metabolism. Micro-PET/CT with 68Ga-FAPI-04 was useful for evaluating pancreatic morphology and fibrosis in CP model mice 2 weeks after modelling. CONCLUSION: St13 is functionally activated in acinar cells and protects against the cellular characteristics of CP by binding Sdf2l1, regulating AA pathway. 68Ga-FAPI-04 PET/CT may be a very valuable approach for the early diagnosis of CP. These findings thus provide novel insights into both diagnosis and treatment of CP.


Assuntos
Células Acinares , Endorribonucleases , Animais , Humanos , Camundongos , Células Acinares/metabolismo , Ácido Araquidônico/metabolismo , Proteínas de Transporte/metabolismo , Endorribonucleases/metabolismo , Fibrose , Radioisótopos de Gálio , Camundongos Knockout , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Proteínas Serina-Treonina Quinases , Tripsina/metabolismo , Proteínas Supressoras de Tumor/metabolismo
13.
Fitoterapia ; 158: 105144, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35149120

RESUMO

Five new α-pyrones, cryptowratones A-E (1-5), and five known congeners (6-10), together with four other known compounds 11-14 were isolated from the twigs of Cryptocarya wrayi. The structures of the new compounds were elucidated on the basis of extensive spectroscopic data analysis and ECD calculations. All α-pyrones except 6 were evaluated for their stimulatory effects on glucose uptake in vitro with CHO-K1/GLUT4 cells. The positive control insulin displayed an approximate 42 ± 0.14% promotion on glucose uptake at 25 µM, compared with the CHO-K1/GLUT4 group. Compounds 1a/2a, 2, 3, and 10 showed a more significant stimulation of glucose uptake than insulin (25 µM) by 36 ± 0.08%, 27 ± 0.12%, 28 ± 0.12%, and 25 ± 0.12% at 1.5 µM, respectively. Immunofluorescence assays indicated the glucose uptake-stimulatory activity of α-pyrones might be correlated with increased GLUT4 translocation.


Assuntos
Cryptocarya , Cryptocarya/química , Glucose , Estrutura Molecular , Pironas/farmacologia
14.
Biol Psychiatry ; 92(3): 204-215, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35151464

RESUMO

BACKGROUND: Major depressive disorder is a devastating psychiatric illness that affects approximately 17% of the population worldwide. Astrocyte dysfunction has been implicated in its pathophysiology. Traumatic experiences and stress contribute to the onset of major depressive disorder, but how astrocytes respond to stress is poorly understood. METHODS: Using Western blotting analysis, we identified that stress vulnerability was associated with reduced astrocytic glucocorticoid receptor (GR) expression in mouse models of depression. We further investigated the functions of astrocytic GRs in regulating depression and the underlying mechanisms by using a combination of behavioral studies, fiber photometry, biochemical experiments, and RNA sequencing methods. RESULTS: GRs in astrocytes were more sensitive to stress than those in neurons. GR absence in astrocytes induced depressive-like behaviors, whereas restoring astrocytic GR expression in the medial prefrontal cortex prevented the depressive-like phenotype. Furthermore, we found that GRs in the medial prefrontal cortex affected astrocytic Ca2+ activity and dynamic ATP (adenosine 5'-triphosphate) release in response to stress. RNA sequencing of astrocytes isolated from GR deletion mice identified the PI3K-Akt (phosphoinositide 3-kinase-Akt) signaling pathway, which was required for astrocytic GR-mediated ATP release. CONCLUSIONS: These findings reveal that astrocytic GRs play an important role in stress response and that reduced astrocytic GR expression in the stressed subject decreases ATP release to mediate stress vulnerability.


Assuntos
Astrócitos , Transtorno Depressivo Maior , Trifosfato de Adenosina/metabolismo , Animais , Astrócitos/metabolismo , Transtorno Depressivo Maior/metabolismo , Glucocorticoides/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Córtex Pré-Frontal/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Glucocorticoides/metabolismo
15.
Mol Psychiatry ; 27(2): 873-885, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34642458

RESUMO

Long-term potentiation (LTP) in the hippocampus is the most studied form of synaptic plasticity. Temporal integration of synaptic inputs is essential in synaptic plasticity and is assumed to be achieved through Ca2+ signaling in neurons and astroglia. However, whether these two cell types play different roles in LTP remain unknown. Here, we found that through the integration of synaptic inputs, astrocyte inositol triphosphate (IP3) receptor type 2 (IP3R2)-dependent Ca2+ signaling was critical for late-phase LTP (L-LTP) but not early-phase LTP (E-LTP). Moreover, this process was mediated by astrocyte-derived brain-derived neurotrophic factor (BDNF). In contrast, neuron-derived BDNF was critical for both E-LTP and L-LTP. Importantly, the dynamic differences in BDNF secretion play a role in modulating distinct forms of LTP. Moreover, astrocyte- and neuron-derived BDNF exhibited different roles in memory. These observations enriched our knowledge of LTP and memory at the cellular level and implied distinct roles of astrocytes and neurons in information integration.


Assuntos
Astrócitos , Fator Neurotrófico Derivado do Encéfalo , Astrócitos/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Potenciação de Longa Duração/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo
16.
Sci Total Environ ; 805: 150383, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818785

RESUMO

Imidacloprid (IMI), an emerging pollutant, has high toxicity to non-target organisms. This paper presents the kinetics of IMI removal by ferrate(VI) at different pH (6.0-9.0), molar ratios ([ferrate(VI)]:[IMI]) and added Fe(III) ions. The apparent second-order rate constant (kapp) decreased with increase in pH from pH 6.0 to 9.0 (i.e., (1.2 ± 0.1) × 102 M-1 s-1 to (8.3 ± 0.3) M-1 s-1). The species-specific rate constants were obtained as k (HFeO4-) = 1.3 × 102 M-1 s-1 and k (FeO42-) = 6.9 M-1 s-1. The decreases in the concentration of HFeO4- with increase in pH caused the observed pH dependence in kapp. At pH 7.0, the removal of IMI increased with the molar ratio from 1.0 to 10.0 with complete removal at the highest ratio. The variation in pH from 6.0 to 9.0 had no obvious effect on removal of IMI. Experiments indicate that IMI removal is mainly by ferrate(VI) oxidation and to a lesser extent by Fe(III) adsorption. Mineralization of IMI was also observed (20-26%). The addition of Fe(III) ions to ferrate(VI)-IMI at pH 7.0 and 8.0 resulted in enhanced removal of IMI, but the presence of Ca2+, SO42-, HCO3-, and humic acid (HA) has negative effects. The presence of coexisting substances in river water slightly decreased IMI removal by ferrate(VI) by less than 10%. Identification of products and frontier electron density (FED) calculations demonstrated involvement of opening of the five-membered heterocyclic moiety of IMI by ferrate(VI). Toxicity assessment with NIH 3T3 fibroblasts and ECOSAR analysis indicated lower toxicity of oxidized products than parent IMI.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Compostos Férricos , Ferro , Cinética , Neonicotinoides , Nitrocompostos , Oxirredução , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
17.
Nat Commun ; 12(1): 3321, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059669

RESUMO

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder. The mechanisms underlying ASD are unclear. Astrocyte alterations are noted in ASD patients and animal models. However, whether astrocyte dysfunction is causal or consequential to ASD-like phenotypes in mice is unresolved. Type 2 inositol 1,4,5-trisphosphate 6 receptors (IP3R2)-mediated Ca2+ release from intracellular Ca2+ stores results in the activation of astrocytes. Mutations of the IP3R2 gene are associated with ASD. Here, we show that both IP3R2-null mutant mice and astrocyte-specific IP3R2 conditional knockout mice display ASD-like behaviors, such as atypical social interaction and repetitive behavior. Furthermore, we show that astrocyte-derived ATP modulates ASD-like behavior through the P2X2 receptors in the prefrontal cortex and possibly through GABAergic synaptic transmission. These findings identify astrocyte-derived ATP as a potential molecular player in the pathophysiology of ASD.


Assuntos
Trifosfato de Adenosina/metabolismo , Astrócitos/patologia , Transtorno do Espectro Autista/patologia , Sinalização do Cálcio/fisiologia , Receptores de Inositol 1,4,5-Trifosfato/deficiência , Animais , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/fisiopatologia , Comportamento Animal , Cálcio/metabolismo , Modelos Animais de Doenças , Neurônios GABAérgicos/fisiologia , Humanos , Receptores de Inositol 1,4,5-Trifosfato/genética , Masculino , Camundongos , Camundongos Knockout , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia , Transmissão Sináptica/fisiologia
18.
Phytochemistry ; 189: 112845, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34171505

RESUMO

Seven undescribed neoflavonoids, named melanoxylonins A-G, were isolated from the heartwood of Dalbergia melanoxylon, and all the non-toxic isolates were evaluated for their cardioprotective effect against ischemia/reoxygenation (I/R) injury in H9c2 cells. Of these, melanoxylonin A-D containing the 8-OH group showed better potent cardioprotective effects than the other four congeners. Molecular docking studies confirmed the capacity of melanoxylonin D to interact with the myeloperoxidase (MPO) protein. These results indicated that the potential cardioprotective effects of melanoxylonin D in H9c2 cells with I/R injury may be imparted through suppression of MPO. These results may provide a new medicinal usage of D. melanoxylon.


Assuntos
Dalbergia , Simulação de Acoplamento Molecular
19.
Neurosci Bull ; 37(1): 1-14, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32785834

RESUMO

Every organism inevitably experiences stress. In the face of acute, intense stress, for example, periods of passivity occur when an organism's actions fail to overcome the challenge. The occurrence of inactive behavior may indicate that struggling would most likely be fruitless. Repeated serious stress has been associated with mood disorders such as depression. The modulation of passive coping response patterns has been explored with a focus on the circuit level. However, the cellular and molecular mechanisms are largely uncharacterized. Here, we report that lactate is a key factor in the astrocytic modulation of the passive coping response to behavioral challenge in adult mice. We found increased extracellular lactate in the medial prefrontal cortex (mPFC) when mice experienced the forced swimming test (FST). Furthermore, we discovered that disturbing astrocytic glycogenolysis, which is a key step for lactate production in the mPFC, decreased the duration of immobility in the FST. Knocking down monocarboxylate transporter 4 (MCT4), which is expressed exclusively in astrocytes and transports lactate from astrocytes to the extracellular space, caused similar results in the FST. The behavioral effect of both the pharmacological disturbance of astrocytic glycogenolysis and viral disruption of MCT4 expression was rescued via the administration of L-lactate. Moreover, we found that both pharmacological and viral modulation of astrocyte-derived lactate in mPFC slices increased the excitability of layer V pyramidal neurons, and this enhancement was reversed by exogenous L-lactate administration. These results highlight astrocyte-derived lactate as a biological mechanism underlying the passive coping response to behavioral challenge and may provide new strategies to prevent mood disorders.


Assuntos
Astrócitos , Ácido Láctico , Adaptação Psicológica , Animais , Masculino , Camundongos , Córtex Pré-Frontal , Estresse Psicológico
20.
Cell Death Dis ; 11(11): 966, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177505

RESUMO

Treatment of acute pancreatitis (AP) and chronic pancreatitis (CP) remains problematic due to a lack of knowledge about disease-specific regulatory targets and mechanisms. The purpose of this study was to screen proteins related to endoplasmic reticulum (ER) stress and apoptosis pathways that may play a role in pancreatitis. Human pancreatic tissues including AP, CP, and healthy volunteers were collected during surgery. Humanized PRSS1 (protease serine 1) transgenic (PRSS1Tg) mice were constructed and treated with caerulein to mimic the development of human AP and CP. Potential regulatory proteins in pancreatitis were identified by proteomic screen using pancreatic tissues of PRSS1Tg AP mice. Adenoviral shRNA-mediated knockdown of identified proteins, followed by functional assays was performed to validate their roles. Functional analyses included transmission electron microscopy for ultrastructural analysis; qRT-PCR, western blotting, co-immunoprecipitation, immunohistochemistry, and immunofluorescence for assessment of gene or protein expression, and TUNEL assays for assessment of acinar cell apoptosis. Humanized PRSS1Tg mice could mimic the development of human pancreatic inflammatory diseases. EMC6 and APAF1 were identified as potential regulatory molecules in AP and CP models by proteomic analysis. Both EMC6 and APAF1 regulated apoptosis and inflammatory injury in pancreatic inflammatory diseases. Moreover, APAF1 was regulated by EMC6, induced apoptosis to injure acinar cells and promoted inflammation. In the progression of pancreatitis, EMC6 was activated and then upregulated APAF1 to induce acinar cell apoptosis and inflammatory injury. These findings suggest that EMC6 may be a new therapeutic target for the treatment of pancreatic inflammatory diseases.


Assuntos
Fator Apoptótico 1 Ativador de Proteases/metabolismo , Proteínas de Membrana/metabolismo , Pancreatite Crônica/metabolismo , Pancreatite Crônica/patologia , Doença Aguda , Animais , Apoptose/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Biologia Molecular/métodos , Pancreatite Crônica/genética , Proteômica/métodos
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