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1.
J Physiol ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953534

RESUMEN

The central histaminergic system has a pivotal role in emotional regulation and psychiatric disorders, including anxiety, depression and schizophrenia. However, the effect of histamine on neuronal activity of the centrolateral amygdala (CeL), an essential node for fear and anxiety processing, remains unknown. Here, using immunostaining and whole-cell patch clamp recording combined with optogenetic manipulation of histaminergic terminals in CeL slices prepared from histidine decarboxylase (HDC)-Cre rats, we show that histamine selectively suppresses excitatory synaptic transmissions, including glutamatergic transmission from the basolateral amygdala, on both PKC-δ- and SOM-positive CeL neurons. The histamine-induced effect is mediated by H3 receptors expressed on VGLUT1-/VGLUT2-positive presynaptic terminals in CeL. Furthermore, optoactivation of histaminergic afferent terminals from the hypothalamic tuberomammillary nucleus (TMN) also significantly suppresses glutamatergic transmissions in CeL via H3 receptors. Histamine neither modulates inhibitory synaptic transmission by presynaptic H3 receptors nor directly excites CeL neurons by postsynaptic H1, H2 or H4 receptors. These results suggest that histaminergic afferent inputs and presynaptic H3 heteroreceptors may hold a critical position in balancing excitatory and inhibitory synaptic transmissions in CeL by selective modulation of glutamatergic drive, which may not only account for the pathophysiology of psychiatric disorders but also provide potential psychotherapeutic targets. KEY POINTS: Histamine selectively suppresses the excitatory, rather than inhibitory, synaptic transmissions on both PKC-δ- and SOM-positive neurons in the centrolateral amygdala (CeL). H3 receptors expressed on VGLUT1- or VGLUT2-positive afferent terminals mediate the suppression of histamine on glutamatergic synaptic transmission in CeL. Optogenetic activation of hypothalamic tuberomammillary nucleus (TMN)-CeL histaminergic projections inhibits glutamatergic transmission in CeL via H3 receptors.

2.
J Biochem ; 176(1): 43-54, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38444151

RESUMEN

Protection against oxidative stress is a vital defense mechanism for Mycobacterium tuberculosis within the host. However, few transcription factors that control bacterial antioxidant defense are known. Here, we present evidence that SdrR, encoded by the MSMEG_5712 (Ms5712) gene, functions as an oxidative stress response regulator in Mycobacterium smegmatis. SdrR recognizes an 11-bp motif sequence in the operon's upstream regulatory region and negatively regulates the expression of short-chain dehydrogenases/reductases (SDR). Overexpressing sdrR inhibited SDR expression, which rendered the strain oxidative more stress-sensitive. Conversely, sdrR knockout alleviates SDR repression, which increases its oxidative stress tolerance. Thus, SdrR responds to oxidative stress by negatively regulating sdr expression. Therefore, this study elucidated an underlying regulatory mechanism behind mycobacterial oxidative stress adaptation.


Asunto(s)
Antioxidantes , Proteínas Bacterianas , Mycobacterium smegmatis , Estrés Oxidativo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Mycobacterium smegmatis/metabolismo , Mycobacterium smegmatis/genética , Antioxidantes/metabolismo , Regulación Bacteriana de la Expresión Génica , Mycobacterium tuberculosis/metabolismo , Operón
4.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38397008

RESUMEN

Although more than 30 different types of neuropeptides have been identified in various cell types and circuits of the cerebellum, their unique functions in the cerebellum remain poorly understood. Given the nature of their diffuse distribution, peptidergic systems are generally assumed to exert a modulatory effect on the cerebellum via adaptively tuning neuronal excitability, synaptic transmission, and synaptic plasticity within cerebellar circuits. Moreover, cerebellar neuropeptides have also been revealed to be involved in the neurogenetic and developmental regulation of the developing cerebellum, including survival, migration, differentiation, and maturation of the Purkinje cells and granule cells in the cerebellar cortex. On the other hand, cerebellar neuropeptides hold a critical position in the pathophysiology and pathogenesis of many cerebellar-related motor and psychiatric disorders, such as cerebellar ataxias and autism. Over the past two decades, a growing body of evidence has indicated neuropeptides as potential therapeutic targets to ameliorate these diseases effectively. Therefore, this review focuses on eight cerebellar neuropeptides that have attracted more attention in recent years and have significant potential for clinical application associated with neurodegenerative and/or neuropsychiatric disorders, including brain-derived neurotrophic factor, corticotropin-releasing factor, angiotensin II, neuropeptide Y, orexin, thyrotropin-releasing hormone, oxytocin, and secretin, which may provide novel insights and a framework for our understanding of cerebellar-related disorders and have implications for novel treatments targeting neuropeptide systems.


Asunto(s)
Enfermedades Cerebelosas , Neuropéptidos , Humanos , Cerebelo/metabolismo , Células de Purkinje/metabolismo , Neuronas/metabolismo , Corteza Cerebelosa/metabolismo , Neuropéptidos/metabolismo , Enfermedades Cerebelosas/patología
5.
Dalton Trans ; 53(10): 4698-4704, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38362640

RESUMEN

Considering the instability and toxicity of 3D Pb-based perovskite nanocrystals, lead-free low-dimensional organic-inorganic hybrid metal halides have attracted widespread attention as potential substitutes. Herein, two new tin-based 0D halides [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O (BAPP = 1,4-bis(3-aminopropyl)piperazine) were synthesized successfully based on [SnX5]3- as an emission center. Typically, [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O display broadband yellow and yellow-green light emissions originating from the radiative recombination of self-trapped excitons (STEs). The photoluminescence quantum yields (PLQYs) of the two compounds were calculated to be 19.27% and 2.36%, respectively. Furthermore, the excellent chemical and thermal stability and broadband light emissions reveal their potential application in solid-state white lighting diodes.

6.
Neuron ; 112(7): 1165-1181.e8, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38301648

RESUMEN

Physical exercise is known to reduce anxiety, but the underlying brain mechanisms remain unclear. Here, we explore a hypothalamo-cerebello-amygdalar circuit that may mediate motor-dependent alleviation of anxiety. This three-neuron loop, in which the cerebellar dentate nucleus takes center stage, bridges the motor system with the emotional system. Subjecting animals to a constant rotarod engages glutamatergic cerebellar dentate neurons that drive PKCδ+ amygdalar neurons to elicit an anxiolytic effect. Moreover, challenging animals on an accelerated rather than a constant rotarod engages hypothalamic neurons that provide a superimposed anxiolytic effect via an orexinergic projection to the dentate neurons that activate the amygdala. Our findings reveal a cerebello-limbic pathway that may contribute to motor-triggered alleviation of anxiety and that may be optimally exploited during challenging physical exercise.


Asunto(s)
Ansiolíticos , Animales , Ansiedad/metabolismo , Hipotálamo , Cerebelo , Trastornos de Ansiedad
7.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1039081

RESUMEN

ObjectiveThis study aimed to observe the impact of sinomenine hydrochloride on the proliferation of fibroblasts and the mRNA expression of related genes in knee joint adhesion and contracture in rabbits. Additionally, we sought to explore its potential mechanisms in combating knee joint adhesion and contracture. MethodsFibroblasts were cultured in vitro, and experimental groups with varying concentrations of sinomenine hydrochloride were established alongside a control group. Cell proliferation was assessed using the CCK-8 assay. Changes in the mRNA expression of fibroblast-related genes following sinomenine hydrochloride treatment were evaluated using RT-qPCR. The impact of the drug on serum levels of inflammatory cytokines was determined using the ELISA method, and the expression of related proteins was assessed using Western blot. ResultsSinomenine hydrochloride was found to inhibit fibroblast viability, with viability decreasing as the concentration of sinomenine hydrochloride increased. The effects of sinomenine hydrochloride in all experimental groups were highly significant (P<0.05). At the mRNA expression level, compared to the control group, sinomenine hydrochloride led to a significant downregulation of inflammatory cytokines in all groups (P<0.05). Additionally, the expression levels of apoptosis-related proteins significantly increased, while Bcl-2 mRNA expression decreased (P<0.05). The mRNA expression levels of the PI3K/mTOR/AKT3 signaling pathway also decreased (P<0.05). At the protein expression level, in comparison to the control group, the levels of inflammatory cytokines IL-6, IL-8, IL-1β, and TGF-β were significantly downregulated in the middle and high-dose sinomenine hydrochloride groups (P<0.05). The expression levels of cleaved-PARP, cleaved caspase-3/7, and Bax increased and were positively correlated with the dose, while the expression levels of the anti-apoptotic protein Bcl-2 and the PI3K/AKT3/mTOR signaling pathway were negatively correlated with the dose. Sinomenine hydrochloride exhibited a significant inhibitory effect on the viability of rabbit knee joint fibroblasts, which may be associated with the downregulation of inflammatory cytokines IL-6, IL-8, and IL-1β, promotion of apoptosis-related proteins cleaved-PARP, cleaved caspase-3/7, and Bax, suppression of Bcl-2 expression, and inhibition of gene expression in the downstream PI3K/AKT3/mTOR signaling pathway. ConclusionSinomenine hydrochloride can inhibit the inflammatory response of fibroblasts in adhesive knee joints and accelerate fibroblast apoptosis. This mechanism may offer a novel approach to improving and treating knee joint adhesion.

8.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-1043970

RESUMEN

Background@#Although trichorhinophalangeal syndrome type 1 (TRPS1) was initially thought to be highly sensitive and specific for carcinomas and mesenchymal tumors of mammary origin, more recent data suggest its expression is not limited to breast neoplasms but also can be seen in other cutaneous neoplasms, such as extramammary Paget disease and squamous cell carcinoma (SCC) in situ. @*Methods@#Two-hundred cases of non-melanocytic cutaneous neoplasm, including basal cell carcinomas (BCCs) (n = 41), SCCs (n = 35), Merkel cell carcinomas (MCCs) (n = 25), and adnexal neoplasms (n = 99), were tested for TRPS1 expression using a monoclonal anti- TRPS1 rabbit anti-human antibody. @*Results@#TRPS1 expression was present in almost all cases of SCC (94%), with a median H-score of 200, while it was either absent or only focally present in most BCCs (90%), with a median H-score of 5. The difference between BCCs and SCCs in H-score was significant (p < .001). All MCCs (100%) lacked TRPS1 expression. TRPS1 expression was frequently seen in most adnexal neoplasms, benign and malignant, in variable intensity and proportion but was consistently absent in apocrine carcinomas. All endocrine mucin-producing sweat gland carcinomas (EMPSGCs) (100%, 6/6) showed diffuse and strong TRPS1 immunoreactivity, with a median H-score of 300, which was significantly different (p < .001) than that of BCCs. @*Conclusions@#Our study shows that TRPS1 may be an effective discriminatory marker for BCCs and SCCs. It also has a role in distinguishing BCCs from EMPSGCs.

9.
Huan Jing Ke Xue ; 44(12): 6474-6485, 2023 Dec 08.
Artículo en Chino | MEDLINE | ID: mdl-38098376

RESUMEN

Based on the PM2.5 samples from Weinan City collected from December 16, 2020 to January 14, 2021, the contamination characteristics of the carbonaceous components and inorganic ions in PM2.5 and the relationship between PM2.5 and water-soluble ions were analyzed. Meanwhile, the sources and source areas were also analyzed by using the positive matrix factorization(PMF), potential source contribution factor(PSCF), and concentration weight trajectory(CWT) methods. The results showed that the night and daytime concentrations of PM2.5, OC, EC, and TWSIIs during the winter in Weinan City were 119.08, 17.02, 6.20, and 34.30 µg·m-3and 130.66, 18.09, 6.22, and 50.65 µg·m-3, respectively. Ion concentrations followed the order of F->NO3->Ca2+>SO42->Na+>Cl->NH4+>K+>Mg2+ during the daytime and NO3->SO42->Ca2+>NH4+>F->Na+>Cl->K+>Mg2+ at night. PM2.5 was acidic during the day and alkaline at night. SOR and NOR values were 0.20 and 0.09, respectively. The R2 values of NH4+ and SO42- during the day and night were 0.04 and 0.09, respectively, and those of NH4+ and NO3- during the day and night were 0.07 and 0.65, respectively. The PMF model analysis showed that the sources of PM2.5 in Weinan City during the winter were mainly coal burning and industrial emission sources, dust sources, and secondary sources. Backward trajectory combined with the potential source analysis indicated that the PM2.5 sources in Weinan City during the winter could be divided into two categories:the first was northwest to the remote source transmission, mainly affected by Gansu, Southern Inner Mongolia, and the Ningxia Hui Autonomous Region; the other category was local emissions, affected by the surrounding neighboring cities of Xianyang, Xi'an, and Tongchuan.

10.
Rev Sci Instrum ; 94(11)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37909839

RESUMEN

A sampling oscilloscope is an important instrument for evaluating the quality of optical communication signals. Since its working principle is equivalent-time sampling, the data obtained for digital signals with random characteristics do not have continuity, which makes it impossible to use methods such as filtering and averaging to equalize the signal. For this reason, this paper proposes a signal equalization method based on reservoir computing. Through training of the reservoir model, an equivalent-time equalizer is established to solve the problem that the sampling oscilloscope cannot equalize random digital signals. Compared with the continuous-time equalizer, the coincidence degree exceeds 95%. The eye height and eye width are increased by 7 and 1.6, respectively, while the jitter in the eye diagram is reduced by 2.3 times, which solves the problem that the sampling oscilloscope cannot equalize random digital signals.

11.
Chembiochem ; 24(22): e202300391, 2023 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-37718314

RESUMEN

We report a fluorescent dye TM by incorporating the tetraphenylethylene (TPE) and cholesterol components into perylene bisimides (PBI) derivative. Fluorescence emission spectrum shows that the dye has stable red emission and aggregation-induced emission (AIE) characteristics. The incorporation of cholesterol components triggers TM to show induced chirality through supramolecular self-assembly. The cRGD-functionalized nanoparticles were prepared by encapsulating fluorescent dyes with amphiphilic polymer matrix. The functionalized fluorescent organic nanoparticles exhibit excellent biocompatibility, large Stokes' shift and good photostability, which make them effective fluorescent probes for targeting cancer cells with high fluorescence contrast.


Asunto(s)
Nanopartículas , Neoplasias , Colorantes Fluorescentes/farmacología , Polímeros , Diagnóstico por Imagen , Colesterol , Neoplasias/diagnóstico por imagen
12.
Free Radic Biol Med ; 208: 780-793, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37703934

RESUMEN

Sepsis often causes organ dysfunction and is manifested in increased endothelial cell permeability in blood vessels. Early-stage inflammation is accompanied by metabolic changes, but it is unclear how the metabolic alterations in the endothelial cells following lipopolysaccharide (LPS) stimulation affect endothelial cell function. In this study, the effects of 1 µg/ml of LPS on the metabolism of human umbilical vein endothelial cells (HUVECs) were investigated, and the metabolic changes after LPS stimulation were explained from the perspective of mRNA expression, chromatin openness and metabolic flux. We found changes in the central metabolism of endothelial cells after LPS stimulation, such as enhanced glycolysis function, decreased mitochondrial membrane potential, and increased production of reactive oxygen species (ROS). Sphingolipid metabolic pathways change at the transcriptome level, and sphingosine-1-phosphatase 2 (SGPP2) was upregulated in LPS-stimulated endothelial cells and zebrafish models. Overexpression of SGPP2 improved cell barrier function, enhanced mitochondrial respiration capacity, but also produced oxidative respiration chain uncoupling. In addition, SGPP2 overexpression inhibited the degradation of HIF-1α protein. The molecular and biochemical processes identified in this study are not only beneficial for understanding the metabolic-related mechanisms of LPS-induced endothelial injury, but also for the discovery of general therapeutic targets for inflammation and inflammation-related diseases.


Asunto(s)
Fenómenos Bioquímicos , Lipopolisacáridos , Animales , Humanos , Células Endoteliales de la Vena Umbilical Humana , Inflamación/genética , Inflamación/metabolismo , Lipopolisacáridos/farmacología , Lipopolisacáridos/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo
13.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2368-2378, 2023 May.
Artículo en Chino | MEDLINE | ID: mdl-37282866

RESUMEN

This study aims to investigate the expression, prognosis, and clinical significance of C5orf46 in gastric cancer and to study the interaction between the active components of C5orf46 and tarditional Chinese medicine. The ggplot2 package was utilized for differential expression analysis of C5orf46 in gastric cancer tissues and normal tissues. The survival package was used for survival analysis, univariate regression analysis, and multivariate regression analysis. Nomogram analysis was used to assess the connection between C5orf46 expression in gastric cancer and overall survival. The abundance of tumor-infiltrating lymphocytes was calculated by GSVA package. Coremine database, Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP) database, and PubChem database were used to search the potential components corresponding to C5orf46 gene and tarditional Chinese medicine. Molecular docking was performed to explore the binding affinity of potential components to C5orf46. Cell experiments were performed to explore the expression of C5orf46 gene in cells of the blank group, model group, and drug administration groups. As compared with normal tissues, C5orf46 expression was higher in gastric cancer tissues, which had more significant predictive effects in the early stages(T2, N0, and M0). The more advanced the tumor node metastasis(TNM) stage, the higher the C5orf46 expression and the lower the probability of survival of patients with gastric cancer. The expression of C5orf46 positively correlated with the helper T cells1 in gastric cancer and the macrophage infiltration level in gastric cancer, and negatively correlated with B cells, central memory T cells, helper T cells 17, and follicular helper T cells. Seven potential components of C5orf46 were obtained, and three active components were obtained after the screening, which matched five tarditional Chinese medicines, namely, Sojae Semen Nigrum, Jujubae Fructus, Trichosanthis Fructus, Silybi Fructus, and Bambusae Concretio Silicea. Molecular docking revealed that sialic acid and adeno-sine monophosphate(AMP) had a good binding ability to C5orf46. The results of real-time quantitative polymerase chain reaction(RT-qPCR) and Western blot showed that, as compared with the model group, the mRNA and protein expression levels of C5orf46 were significantly lower in the drug administration groups. The lowest expression level was found at the concentration of 40 µmol·L~(-1). The results of this study provide ideas for the clinical development of traditional Chinese medicine compounds for the treatment of gastric cancer as well as other cancers.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Pronóstico , Biología Computacional
14.
Neuropharmacology ; 235: 109576, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37164226

RESUMEN

The cumulative evidence suggests that oxytocin is involved in the male sexual behaviors. However, no significant sexual impairments were observed in oxytocin gene knock-out (KO) mice, suggesting that oxytocin is not necessary for sexual behavior in male mice. To better understand the role of oxytocin in male erection, two types of oxytocin gene KO mice were created. In the first type, the oxytocin gene was deleted in the zygote, while in the second type, the oxytocin gene was mutated in adulthood by injecting the CRISPR/Cas9 AAVs. The results showed that disrupting the oxytocin gene at either the embryonic or adult stage did not affect erection, indicating that oxytocin is not necessary for penile erection. Pharmacologically, injecting oxytocin receptor agonist Carbetocin into the VTA of the oxytocin gene KO mice still evoked penile erection. By employing the Oxt-Ires-Cre mice, we found that specifically activating oxytocinergic neurons through chemogenetics strongly induced penile erection, while inhibiting these neurons blocked the erection responses. Furthermore, ablating PVN oxytocinergic neurons abolished the male erection response. In conclusion, although the neuropeptide oxytocin is not essential for male erection, the activity of oxytocinergic neurons is required. Our results might reflect the redundancy in the central nerve system in the sense that many signals contribute to the activation of oxytocinergic neurons to evoke penile erection during sexual behaviors.


Asunto(s)
Neuronas , Oxitocina , Erección Peniana , Animales , Masculino , Ratones , Neuronas/fisiología , Núcleo Hipotalámico Paraventricular , Erección Peniana/fisiología , Receptores de Oxitocina/genética , Oxitocina/metabolismo
15.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1535-1545, 2023 Mar.
Artículo en Chino | MEDLINE | ID: mdl-37005841

RESUMEN

To compare the pancreatic proteomics and autophagy between Rehmanniae Radix-and Rehmanniae Radix Praeparata-treated mice with type 2 diabetes mellitus(T2DM). The T2DM mouse model was established by high-fat diet coupled with streptozotocin(STZ, intraperitoneal injection, 100 mg·kg~(-1), once a day for three consecutive days). The mice were then randomly assigned into a control group, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) catalpol groups, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix Praeparata groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) 5-hydroxymethyl furfuraldehyde(5-HMF) groups, and a metformin(250 mg·kg~(-1)) group. In addition, a normal group was also set and each group included 8 mice. The pancreas was collected after four weeks of administration and proteomics tools were employed to study the effects of Rehmanniae Radix and Rehmanniae Radix Praeparata on protein expression in the pancreas of T2DM mice. The expression levels of proteins involved in autophagy, inflammation, and oxidative stress response in the pancreatic tissues of T2DM mice were determined by western blotting, immunohistochemical assay, and transmission electron microscopy. The results showed that the differential proteins between the model group and Rehmanniae Radix/Rehmanniae Radix Prae-parata group were enriched in 7 KEGG pathways, such as autophagy-animal, which indicated that the 7 pathways may be associated with T2DM. Compared with the control group, drug administration significantly up-regulated the expression levels of beclin1 and phosphorylated mammalian target of rapamycin(p-mTOR)/mTOR and down-regulated those of the inflammation indicators, Toll-like receptor-4(TLR4) and Nod-like receptor protein 3(NLRP3), in the pancreas of T2DM mice, and Rehmanniae Radix showed better performance. In addition, the expression levels of inducible nitric oxide synthase(iNOS), nuclear factor erythroid 2-related factor 2(Nrf2), and heine oxygenase-1(HO-1) in the pancreas of T2DM mice were down-regulated after drug administration, and Rehmanniae Radix Praeparata demonstrated better performance. The results indicate that both Rehmanniae Radix and Rehmanniae Radix Praeparata can alleviate the inflammatory symptoms, reduce oxidative stress response, and increase the autophagy level in the pancreas of T2DM mice, while they exert the effect on different autophagy pathways.


Asunto(s)
Diabetes Mellitus Tipo 2 , Ratones , Animales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Estreptozocina/farmacología , Dieta Alta en Grasa/efectos adversos , Proteómica , Inflamación , Serina-Treonina Quinasas TOR , Autofagia , Mamíferos
16.
Pharmacol Res ; 191: 106773, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37068531

RESUMEN

Specific medications to combat cerebellar ataxias, a group of debilitating movement disorders characterized by difficulty with walking, balance and coordination, are still lacking. Notably, cerebellar microglial activation appears to be a common feature in different types of ataxic patients and rodent models. However, direct evidence that cerebellar microglial activation in vivo is sufficient to induce ataxia is still lacking. Here, by employing chemogenetic approaches to manipulate cerebellar microglia selectively and directly, we found that specific chemogenetic activation of microglia in the cerebellar vermis directly leads to ataxia symptoms in wild-type mice and aggravated ataxic motor deficits in 3-acetylpyridine (3-AP) mice, a classic mouse model of cerebellar ataxia. Mechanistically, cerebellar microglial proinflammatory activation induced by either chemogenetic M3D(Gq) stimulation or 3-AP modeling hyperexcites Purkinje cells (PCs), which consequently triggers ataxia. Blockade of microglia-derived TNF-α, one of the most important proinflammatory cytokines, attenuates the hyperactivity of PCs driven by microglia. Moreover, chemogenetic inhibition of cerebellar microglial activation or suppression of cerebellar microglial activation by PLX3397 and minocycline reduces the production of proinflammatory cytokines, including TNF-α, to effectively restore the overactivation of PCs and alleviate motor deficits in 3-AP mice. These results suggest that cerebellar microglial activation may aggravate the neuroinflammatory response and subsequently induce dysfunction of PCs, which in turn triggers ataxic motor deficits. Our findings thus reveal a causal relationship between proinflammatory activation of cerebellar microglia and ataxic motor symptoms, which may offer novel evidence for therapeutic intervention for cerebellar ataxias by targeting microglia and microglia-derived inflammatory mediators.


Asunto(s)
Ataxia Cerebelosa , Ratones , Animales , Ataxia Cerebelosa/inducido químicamente , Células de Purkinje/fisiología , Microglía , Factor de Necrosis Tumoral alfa/farmacología , Cerebelo , Citocinas
17.
Nat Neurosci ; 26(4): 542-554, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36941428

RESUMEN

Reactive astrocytes play an important role in neurological diseases, but their molecular and functional phenotypes in epilepsy are unclear. Here, we show that in patients with temporal lobe epilepsy (TLE) and mouse models of epilepsy, excessive lipid accumulation in astrocytes leads to the formation of lipid-accumulated reactive astrocytes (LARAs), a new reactive astrocyte subtype characterized by elevated APOE expression. Genetic knockout of APOE inhibited LARA formation and seizure activities in epileptic mice. Single-nucleus RNA sequencing in TLE patients confirmed the existence of a LARA subpopulation with a distinct molecular signature. Functional studies in epilepsy mouse models and human brain slices showed that LARAs promote neuronal hyperactivity and disease progression. Targeting LARAs by intervention with lipid transport and metabolism could thus provide new therapeutic options for drug-resistant TLE.


Asunto(s)
Epilepsia del Lóbulo Temporal , Epilepsia , Humanos , Ratones , Animales , Astrocitos/metabolismo , Progresión de la Enfermedad , Modelos Animales de Enfermedad , Lípidos , Apolipoproteínas E/metabolismo , Hipocampo/metabolismo
18.
J Radiol Prot ; 43(1)2023 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-36649650

RESUMEN

The neutron dose resulting from external irradiation can be evaluated by measuring the counts of characteristicγrays produced by24Na in the human body. The detection geometry with the highest detection efficiency for measuring the whole-body24Na activity has not been studied. In this work, the MCNP code is used to calculate the spatial distribution of24Na in the human body irradiated by neutrons with different energies in different irradiation geometries. The fluence distribution of24Na characteristicγrays on the body surface is calculated. The counts of24Na characteristicγrays induced by monochromatic neutron irradiation are simulated to fit the scenarios of neutron irradiation by a continuous energy spectrum neutron. When the spontaneous neutrons from252Cf with 1Gy dose irradiate the human body, (3.63-4.35) × 1010 24Na atoms are produced. The lower detection limit for the neutron absorption dose is reduced from ∼100 to less than 1 mGy when the radiation detector is placed over the back of the human body close to the liver. The relative error between the measured counts of24Na characteristic γ rays caused by252Cf neutron irradiation and the counts fitted by monochromatic neutron irradiation data is less than 5.7%. The neutron dose received from a continuous energy spectrum neutron can be acquired quickly and accurately by weighted summing of the data for monochromatic neutron irradiations calculated in this paper, which is more convenient and practical than the previous method.


Asunto(s)
Cuerpo Humano , Neutrones , Humanos , Dosis de Radiación
19.
Adv Sci (Weinh) ; 10(8): e2206681, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36651112

RESUMEN

Fast and selective fluorescence imaging for a biomarker to related-disease diagnosis remains a significant challenge due to complex physical environment. Human carboxylesterase (CE) is expected to be a potential biomarker of hepatocellular carcinoma (HCC) to improve the accuracy of diagnosis. However, existing probes for CE has slow response rate and low selectivity. Herein, the amide group is selected as CE-responsive sites based on the "substrate-hydrolysis enzymatic reaction" approach. From a series of off-on probes with leave groups in the amide unit, probe JFast is screened with the optimal combination of rapid response rate and high selectivity toward CE. JFast requires only 150 s to reach the maximum fluorescence at 676 nm in the presence of CE and free from the interference of other esterase. Computational docking simulations indicate the shortest distance between the CE and active site of JFast . Cell and in vivo imaging present that the probe can turn on the liver cancer cells and tumor region precisely. Importantly, JFast is allowed to specifically image orthotopic liver tumor rather than metastatic tumor and distinguish human primary liver cancer tissue from adjacent ones. This study provides a new tool for CE detection and promotes advancements in accurate HCC diagnosis.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Carboxilesterasa/química , Neoplasias Hepáticas/diagnóstico por imagen , Amidas , Colorantes Fluorescentes/química
20.
Cerebellum ; 22(5): 888-904, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36040660

RESUMEN

The classical motor center cerebellum is one of the most consistent structures of abnormality in autism spectrum disorders (ASD), and neuropeptide oxytocin is increasingly explored as a potential pharmacotherapy for ASD. However, whether oxytocin targets the cerebellum for therapeutic effects remains unclear. Here, we report a localization of oxytocin receptor (OXTR) in Purkinje cells (PCs) of cerebellar lobule Crus I, which is functionally connected with ASD-implicated circuits. OXTR activation neither affects firing activities, intrinsic excitability, and synaptic transmission of normal PCs nor improves abnormal intrinsic excitability and synaptic transmission of PCs in maternal immune activation (MIA) mouse model of autism. Furthermore, blockage of OXTR in Crus I in wild-type mice does not induce autistic-like social, stereotypic, cognitive, and anxiety-like behaviors. These results suggest that oxytocin signaling in Crus I PCs seems to be uninvolved in ASD pathophysiology, and contribute to understanding of targets and mechanisms of oxytocin in ASD treatment.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Ratones , Animales , Receptores de Oxitocina , Oxitocina , Células de Purkinje
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