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Positron emission tomography (PET) imaging employs positron-emitting radioisotopes to visualize biological processes in living subjects with high sensitivity and quantitative accuracy. As the most translational molecular imaging modality, PET can detect and image a wide range of radiotracers with minimal or no modification to parent drugs or targeting molecules. This Perspective provides a comprehensive analysis of developing PET radioligands using allosteric modulators for the metabotropic glutamate receptor subtype 4 (mGluR4) as a therapeutic target for neurological disorders. We focus on the selection of lead compounds from various chemotypes of mGluR4 positive allosteric modulators (PAMs) and discuss the challenges and systematic characterization required in developing brain-penetrant PET tracers specific for mGluR4. Through this analysis, we offer insights into the development and evaluation of PET ligands. Our review concludes that further research and development in this field hold great promise for discovering effective treatments for neurological disorders.
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Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Receptores de Glutamato Metabotrópico , Tomografia por Emissão de Pósitrons/métodos , Humanos , Receptores de Glutamato Metabotrópico/metabolismo , Animais , Compostos Radiofarmacêuticos/química , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Regulação Alostérica , LigantesRESUMO
Alzheimer's disease (AD), a progressive neurodegenerative disorder, has garnered increased attention due to its substantial economic burden and the escalating global aging phenomenon. Amyloid-ß deposition is a key pathogenic marker observed in the brains of Alzheimer's sufferers. Based on real-time, safe, low-cost, and commonly used, near-infrared fluorescence (NIRF) imaging technology have become an essential technique for the detection of AD in recent years. In this work, NIRF probes with hemicyanine structure were designed, synthesized and evaluated for imaging Aß aggregates in the brain. We use the hemicyanine structure as the parent nucleus to enhance the probe's optical properties. The introduction of PEG chain is to improve the probe's brain dynamice properties, and the alkyl chain on the N atom is to enhance the fluorescence intensity of the probe after binding to the Aß aggregates as much as possible. Among these probes, Z2, Z3, Z6, X3, X6 and T1 showed excellent optical properties and high affinity to Aß aggregates (Kd = 24.31 â¼ 59.60 nM). In vitro brain section staining and in vivo NIRF imaging demonstrated that X6 exhibited superior discrimination between Tg mice and WT mice, and X6 has the best brain clearance rate. As a result, X6 was identified as the optimal probe. Furthermore, the docking theory calculation results aided in describing X6's binding behavior with Aß aggregates. As a high-affinity, high-selectivity, safe and effective probe of targeting Aß aggregates, X6 is a promising NIRF probe for in vivo detection of Aß aggregates in the AD brain.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Carbocianinas , Desenho de Fármacos , Corantes Fluorescentes , Imagem Óptica , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/análise , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Animais , Carbocianinas/química , Carbocianinas/síntese química , Camundongos , Estrutura Molecular , Humanos , Agregados Proteicos , Relação Estrutura-Atividade , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Relação Dose-Resposta a DrogaRESUMO
BACKGROUND: Isolated microspore culture is a useful biotechnological technique applied in modern plant breeding programs as it can produce doubled haploid (DH) plants and accelerate the development of new varieties. Furthermore, as a single-cell culture technique, the isolated microspore culture provides an excellent platform for studying microspore embryogenesis. However, the reports on isolated microspore culture are rather limited in rice due to the low callus induction rate, poor regeneration capability, and high genotypic dependency. The present study developed an effective isolated microspore culture protocol for high-frequency androgenesis in four japonica rice genotypes. Several factors affecting the isolated microspore culture were studied to evaluate their effects on callus induction and plantlet regeneration. RESULTS: Low-temperature pre-treatment at 4 â for 10-15 days could effectively promote microspore embryogenesis in japonica rice. A simple and efficient method was proposed for identifying the microspore developmental stage. The anthers in yellow-green florets located on the second type of primary branch on the rice panicle were found to be the optimal stage for isolated microspore culture. The most effective induction media for callus induction were IM2 and IM3, depending on the genotype. The optimal concentration of 2, 4-D in the medium for callus induction was 1 mg/L. Callus induction was negatively affected by a high concentration of KT over 1.5 mg/L. The differentiation medium suitable for japonica rice microspore callus comprised 1/2 MS, 2 mg/L 6-BA, 0.5 mg/L NAA, 30 g/L sucrose, and 6 g/L agar. The regeneration frequency of the four genotypes ranged from 61-211 green plantlets per 100 mg calli, with Chongxiangjing showing the highest regeneration frequency. CONCLUSIONS: This study presented an efficient protocol for improved callus induction and green plantlet regeneration in japonica rice via isolated microspore culture, which could provide valuable support for rice breeding and genetic research.
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A two-photon near infrared (NIR) fluorescence turn-on sensor with high selectivity and sensitivity for Zn2+ detection has been developed. This sensor exhibits a large Stokes' shift (â¼300 nm) and can be excited from 900 to 1000 nm, with an emission wavelength of â¼785 nm, making it ideal for imaging in biological tissues. The sensor's high selectivity for Zn2+ over other structurally similar cations, such as Cd2+, makes it a promising tool for monitoring zinc ion levels in biological systems. Given the high concentration of zinc in thrombi, this sensor could provide a useful tool for in vivo thrombus imaging.
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In this study, a series of carbamate derivatives incorporating multifunctional carrier scaffolds were designed, synthesized, and evaluated as potential therapeutic agents for Alzheimer's disease (AD). We used tacrine to modify the aliphatic substituent, and employed rivastigmine, indole and sibiriline fragments as carrier scaffolds. The majority of compounds exhibited good inhibitory activity for cholinesterase. Notably, compound C7 with sibiriline fragment exhibited potent inhibitory activities against human acetylcholinesterase (hAChE, IC50 = 30.35 ± 2.07 nM) and human butyrylcholinesterase (hBuChE, IC50 = 48.03 ± 6.41 nM) with minimal neurotoxicity. Further investigations have demonstrated that C7 exhibited a remarkable capacity to safeguard PC12 cells against H2O2-induced apoptosis and effectively suppressed the production of reactive oxygen species (ROS). Moreover, in an inflammation model of BV2 cells induced by lipopolysaccharide (LPS), C7 effectively attenuated the levels of pro-inflammatory cytokines. After 12 h of dialysis, C7 continued to exhibit an inhibitory effect on cholinesterase activity. An acute toxicity test in vivo demonstrated that C7 exhibited a superior safety profile and no hepatotoxicity compared to the parent nucleus tacrine. In the scopolamine-induced AD mouse model, C7 (20 mg/kg) significantly reduced cholinesterase activity in the brain of the mice. C7 was tested in a pharmacological AD mouse model induced by Aß1-42 and attenuated memory deficits at doses as low as 5 mg/kg. The pseudo-irreversible cholinesterase inhibitory properties and multifunctional therapeutic attributes of C7 render it a promising candidate for further investigation in the treatment of AD.
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Doença de Alzheimer , Inibidores da Colinesterase , Ratos , Camundongos , Humanos , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/induzido quimicamente , Butirilcolinesterase/metabolismo , Tacrina/farmacologia , Tacrina/uso terapêutico , Acetilcolinesterase/metabolismo , Carbamatos/farmacologia , Peróxido de Hidrogênio/farmacologia , Peptídeos beta-Amiloides , Barreira Hematoencefálica/metabolismo , Desenho de Fármacos , Relação Estrutura-AtividadeRESUMO
Barley is the most salt-tolerant cereal crop. However, little attention has been paid to the salt-tolerant doubled haploids of barley derived from mutagenesis combined with isolated microspore culture. In the present study, barley doubled haploid (DH) line 20, which was produced by mutagenesis combined with isolated microspore culture, showed stably and heritably better salt tolerance than the wild type H30 in terms of fresh shoot weight, dry shoot weight, K+/Na+ ratio and photosynthetic characteristics. Transcriptome and metabolome analyses were performed to compare the changes in gene expression and metabolites between DH20 and H30. A total of 462 differentially expressed genes (DEGs) and 152 differentially accumulated metabolites (DAMs) were identified in DH20 compared to H30 under salt stress. Among the DAMs, fatty acids were the most accumulated in DH20 under salt stress. The integration of transcriptome and metabolome analyses revealed that nine key biomarkers, including two metabolites and seven genes, could distinguish DH20 and H30 when exposed to high salt. The pathways of linoleic acid metabolism, alpha-linolenic acid metabolism, glycerolipid metabolism, photosynthesis, and alanine, aspartate and glutamate metabolism were significantly enriched in DH20 with DEGs and DAMs in response to salt stress. These results suggest that DH20 may enhance resilience by promoting lipid metabolism, maintaining energy metabolism and decreasing amino acids metabolism. The study provided novel insights for the rapid generation of homozygous mutant plants by mutagenesis combined with microspore culture technology and also identified candidate genes and metabolites that may enable the mutant plants to cope with salt stress.
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Hordeum , Transcriptoma , Tolerância ao Sal/genética , Hordeum/metabolismo , Metabolismo dos Lipídeos/genética , Estresse Fisiológico/genética , Perfilação da Expressão Gênica , Fotossíntese/genética , Mutagênese , SalinidadeRESUMO
Introduction: To investigate the therapeutic effect of clitoris exposure + episioplasty + dermabrasion + platelet-rich plasma (PRP) injection + chemexfoliation on vulvar lichen sclerosus (VLS). Methods: Twenty children with VLS (under 14 years old) at our hospital from July 2020 to November 2022 were enrolled and treated with clitoris exposure + episioplasty + dermabrasion + PRP injection + chemexfoliation. Additionally, symptomatic changes and improvements in signs were recorded. Results: Significant therapeutic effects were achieved in all children enrolled in this study. The Cattanco score was 8.02 ± 1.22 points before surgery, 2.21 ± 0.70 points 3 months after surgery, and 2.61 ± 0.59 points 6 months after surgery, demonstrating that the score after surgery was significantly lower than that before surgery (p < 0.05). Mild complications (one case of mild vulvar swelling, one case of minor bleeding, and one case of superficial ulcer) were observed in three children after surgery, with an overall complication incidence of 15%; all complications were improved after the intervention, and no severe adverse reactions were observed. Recurrence was observed in one child (5%) 6 months after surgery. Conclusion: Clitoris exposure + episioplasty + dermabrasion + PRP injection + chemexfoliation is an effective approach for the treatment of VLS. Systematic Review Registration: https://www.chictr.org.cn/searchproj.html, identifier: ChiCTR2100054787.
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BACKGROUND: Microspore culture is one of the important biotechnological tools in plant breeding. The induction of microspore embryogenesis is a critical factor that affects the yield of microspore-derived embryo productions. Cold treatment has been reported to reprogram the gametophytic pathway in various plant species. However, the exact mechanism(s) underlying the effect of cold pre-treatment of floral buds on the efficiency of ME is still not clear. RESULTS: In this study, the effects of cold stress on the microspore totipotency of rice cultivar Zhonghua 11 were investigated. Our results revealed that a 10-day cold treatment is necessary for microspore embryogenesis initiation. During this period, the survival rate of microspores increased and reached a peak at 7 days post treatment (dpt), before decreasing at 10 dpt. RNA-seq analysis showed that the number of DEGs increased from 3 dpt to 10 dpt, with more downregulated DEGs than upregulated ones at the same time point. GO enrichment analysis showed a shift from 'Response to abiotic stimulus' at 3 dpt to 'Metabolic process' at 7 and 10 dpt, with the most significant category in the cellular component being 'cell wall'. KEGG analysis of the pathways revealed changes during cold treatment. Mass spectrometry was used to evaluate the variations in metabolites at 10 dpt compared to 0 dpt, with more downregulated DEMs being determined in both GC-MS and LC-MS modes. These DEMs were classified into 11 categories, Most of the DEMs belonged to 'lipids and lipid-like molecules'. KEGG analysis of DEMs indicates pathways related to amino acid and nucleotide metabolism being upregulated and those related to carbohydrate metabolism being downregulated. An integration analysis of transcriptomics and metabolomics showed that most pathways belonged to 'Amino acid metabolism' and 'Carbohydrate metabolism'. Four DEMs were identified in the interaction network, with stearidonic acid involving in the most correlations, suggesting the potential role in microspore totipotency. CONCLUSIONS: Our findings exhibited the molecular events occurring during stress-induced rice microspore. Pathways related to 'Amino acid metabolism' and 'Carbohydrate metabolism' may play important roles in rice microspore totipotency. Stearidonic acid was identified, which may participate in the initiation of microspore embryogenesis.
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Resposta ao Choque Frio , Oryza , Transcriptoma , Oryza/genética , Melhoramento Vegetal , AminoácidosRESUMO
Nanobodies (Nbs) hold significant potential in molecular imaging due to their unique characteristics. However, there are challenges to overcome when it comes to brain imaging. To address these obstacles, collaborative efforts and interdisciplinary research are needed. This article aims to raise awareness and encourage collaboration among researchers from various fields to find solutions for effective brain imaging using Nbs. By fostering cooperation and knowledge sharing, we can make progress in overcoming the existing limitations and pave the way for improved molecular imaging techniques in the future.
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Anticorpos de Domínio Único , Anticorpos de Domínio Único/metabolismo , Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/metabolismo , Imagem Molecular/métodosRESUMO
The BET protein family plays a crucial role in regulating the epigenetic landscape of the genome. Their role in regulating tumor-related gene expression and its impact on the survival of tumor cells is widely acknowledged. Among the BET family constituents, BRD4 is a significant protein. It is a bromodomain-containing protein located at the outer terminal that recognizes histones that have undergone acetylation. It is present in the promoter or enhancer region of the target gene and is responsible for initiating and sustaining the expression of genes associated with tumorigenesis. BRD4 expression is significantly elevated in various tumor types. Research has indicated that BRD4 plays a significant role in regulating various transcription factors and chromatin modification, as well as in repairing DNA damage and preserving telomere function, ultimately contributing to the survival of cancerous cells. The protein BRD4 has a significant impact on antitumor therapy, particularly in the management of lung cancer and hematological malignancies, and the promising potential of BRD4 inhibitors in the realm of cancer prevention and treatment is a topic of great interest. Therefore, BRD4 is considered a promising candidate for prophylaxis and therapy of neoplastic diseases. However, further research is required to fully comprehend the significance and indispensability of BRD4 in cancer and its potential as a therapeutic target.
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Neoplasias Hematológicas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Nucleares/genética , Fatores de Transcrição/metabolismo , Proteínas de Ciclo Celular , Neoplasias Hematológicas/tratamento farmacológico , Proteínas que Contêm BromodomínioRESUMO
KEY MESSAGES: Narrowing down to a single putative target gene behind a leaf senescence mutant and constructing the regulation network by proteomic method. Leaf senescence mutant is an important resource for exploring molecular mechanism of aging. To dig for potential modulation networks during maize leaf aging process, we delimited the gene responsible for a premature leaf senescence mutant els5 to a 1.1 Mb interval in the B73 reference genome using a BC1F1 population with 40,000 plants, and analyzed the leaf proteomics of the mutant and its near-isogenic wild type line. A total of 1355 differentially accumulated proteins (DAP) were mainly enriched in regulation pathways such as "photosynthesis", "ribosome", and "porphyrin and chlorophyll metabolism" by the KEGG pathway analysis. The interaction networks constructed by incorporation of transcriptome data showed that ZmELS5 likely repaired several key factors in the photosynthesis system. The putative candidate proteins for els5 were proposed based on DAPs in the fined QTL mapping interval. These results provide fundamental basis for cloning and functional research of the els5 gene, and new insights into the molecular mechanism of leaf senescence in maize.
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Senescência Vegetal , Zea mays , Zea mays/genética , Proteômica/métodos , Transcriptoma , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas/genéticaRESUMO
AIM: To investigate the clinical application of thromboelastography (TEG) in severe fever with thrombocytopenia syndrome (SFTS). METHODS: One hundred and fifty-seven patients with SFTS were included in the study. The participants were distributed into 3 groups; A, B, and C. And 103 patients in group A met the clinical criteria as they exhibited slight liver and kidney dysfunction. Group B consisted of 54 patients with SFTS who were critically ill while group C was a healthy control group with 58 participants. RESULTS: Patients with SFTS exhibited lower coagulation than the healthy participants. Group B patients exhibited significantly lower coagulation compared to group A. There was no significant difference in platelet count and fibrinogen content between patients in group A and group B, but platelet aggregation function and fibrinogen activity were significantly lower in group B patients. CONCLUSION: Our results suggest that it is risky to solely rely on platelet count and the fibrinogen in SFTS. Monitoring of TEG and other coagulation indexes should be emphasized.
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Febre Grave com Síndrome de Trombocitopenia , Tromboelastografia , Humanos , Tromboelastografia/métodos , Fibrinogênio/análise , Coagulação Sanguínea , HemostasiaRESUMO
Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder characterized by atypical patterns of social interaction and communication, as well as restrictive and repetitive behaviors. In addition, patients with ASD often presents with sleep disturbances. Delta (δ) catenin protein 2 (CTNND2) encodes δ-catenin protein, a neuron-specific catenin implicated in many complex neuropsychiatric diseases. Our previous study demonstrated that the deletion of Ctnnd2 in mice led to autism-like behaviors. However, to our knowledge, no study has investigated the effects of Ctnnd2 deletion on sleep in mice. In this study, we investigated whether the knockout (KO) of exon 2 of the Ctnnd2 gene could induce sleep-wake disorders in mice and identified the effects of oral melatonin (MT) supplementation on Ctnnd2 KO mice. Our results demonstrated that the Ctnnd2 KO mice exhibited ASD-like behaviors and sleep-wake disorders that were partially attenuated by MT supplementation. Overall, our current study is the first to identify that knockdown of Ctnnd2 gene could induce sleep-wake disorders in mice and suggests that treatment of sleep-wake disturbances by MT may benefit to autism-like behaviors causing by Ctnnd2 gene deletion.
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Transtorno do Espectro Autista , Transtorno Autístico , Melatonina , Transtornos do Sono-Vigília , Camundongos , Animais , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno do Espectro Autista/genética , Camundongos Knockout , Melatonina/farmacologia , Melatonina/uso terapêutico , Transtornos do Sono-Vigília/tratamento farmacológico , Transtornos do Sono-Vigília/genética , SonoRESUMO
INTRODUCTION: Sleep abnormalities are highly correlated with neurodevelopmental disorders, such as intellectual disability, attention deficit hyperactivity disorder, and autism spectrum disorders (ASD). The severity of behavioral abnormalities is correlated with the presence of sleep abnormalities. Based on previous research, we investigated that Ctnnd2 gene deletion in mice lead to ASD-like behaviors and cognitive defects. Given the importance of sleep in individuals with ASD, this study aimed to determine the effects of chronic sleep restriction (SR) on wild-type (WT) mice and on Ctnnd2 deletion-induced, neurologically related phenotypes in mice. METHOD: WT and Ctnnd2 knockout (KO) mice were both subjected to manual SR (5 h per day) for 21 consecutively days separately, then we compared neurologically related phenotypes of WT mice, WT mice subjected to SR, KO mice, and KO mice subjected to SR using a three-chamber assay, direct social interaction test, open-field test, Morris water maze, Golgi staining, and Western blotting. RESULTS: The effects of SR on WT and KO mice were different. After SR, social ability and cognition were impaired in both WT and KO mice. Repetitive behaviors were increased, and exploration abilities were decreased in KO mice but not in WT mice. Moreover, SR reduced the density and area of mushroom-type dendritic spines in WT rather than KO mice. Finally, the PI3K/Akt-mTOR pathway was found to be involved in the effects induced by SR-impaired phenotypes in WT and KO mice. CONCLUSION: Overall, results of the present study may have implications for the role of disrupted sleep in patients with CTNND2 gene-related autism and the evolution of neurodevelopmental disorders.
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Transtorno do Espectro Autista , Transtorno Autístico , Animais , Camundongos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/psicologia , Modelos Animais de Doenças , Camundongos Knockout , Fenótipo , Fosfatidilinositol 3-Quinases , SonoRESUMO
Purpose: Precisely detecting colorectal liver metastases (CLMs), the leading cause of colorectal cancer-associated mortality, is extremely important. 1H MRI with high soft tissue resolution plays a key role in the diagnosing liver lesions; however, precise detecting CLMs by 1H MRI is a great challenge due to the limited sensitivity. Even though contrast agents may improve the sensitivity, due to their short half-life, repeated injections are required to monitor the changes of CLMs. Herein, we synthesized c-Met-targeting peptide-functionalized perfluoro-15-crown-5-ether nanoparticles (AH111972-PFCE NPs), for highly sensitive and early diagnosis of small CLMs. Methods: The size, morphology and optimal properties of the AH111972-PFCE NPs were characterized. c-Met specificity of the AH111972-PFCE NPs was validated by in vitro experiment and in vivo 19F MRI study in the subcutaneous tumor murine model. The molecular imaging practicability and long tumor retention of the AH111972-PFCE NPs were evaluated in the liver metastases mouse model. The biocompatibility of the AH111972-PFCE NPs was assessed by toxicity study. Results: AH111972-PFCE NPs with regular shape have particle size of 89.3 ± 17.8 nm. The AH111972-PFCE NPs exhibit high specificity, strong c-Met-targeting ability, and precise detection capability of CLMs, especially small or ill-defined fused metastases in 1H MRI. Moreover, AH111972-PFCE NPs could be ultralong retained in metastatic liver tumors for at least 7 days, which is conductive to the implementation of continuous therapeutic efficacy monitoring. The NPs with minimal side effects and good biocompatibility are cleared mainly via the spleen and liver. Conclusion: The c-Met targeting and ultralong tumor retention of AH111972-PFCE NPs will contribute to increasing therapeutic agent accumulation in metastatic sites, laying a foundation for CLMs diagnosis and further c-Met targeted treatment integration. This work provides a promising nanoplatform for the future clinical application to patients with CLMs.
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Neoplasias Colorretais , Neoplasias Hepáticas , Nanopartículas , Camundongos , Animais , Imageamento por Ressonância Magnética , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Colorretais/diagnóstico por imagemRESUMO
Autism spectrum disorder (ASD) is a common neurodevelopmental disorder with onset in childhood. The mechanisms underlying ASD are unclear. In recent years, the role of microglia and astrocytes in ASD has received increasing attention. Microglia prune the synapses or respond to injury by sequestrating the injury site and expressing inflammatory cytokines. Astrocytes maintain homeostasis in the brain microenvironment through the uptake of ions and neurotransmitters. However, the molecular link between ASD and microglia and, or astrocytes remains unknown. Previous research has shown the significant role of microglia and astrocytes in ASD, with reports of increased numbers of reactive microglia and astrocytes in postmortem tissues and animal models of ASD. Therefore, an enhanced understanding of the roles of microglia and astrocytes in ASD is essential for developing effective therapies. This review aimed to summarize the functions of microglia and astrocytes and their contributions to ASD.