Cyclic GMP-AMP synthase (cGAS), a pivotal molecule in innate immunity, has emerged as a keypoint in interdisciplinary research at the intersection of basic immunology and tumor biology. As a cytosolic nucleic acid sensor, cGAS is primarily characterized by its capacity to recognize double-stranded DNA (dsDNA) in the cytosol. Upon binding to dsDNA, cGAS undergoes a conformational change that promotes its dimerization and subsequent enzymatic activation. Once activated, it catalyzes the synthesis of the second messenger 2',3'-cGAMP from ATP and GTP. cGAMP then binds to the adaptor protein STING, which resides on the endoplasmic reticulum (ER) membrane. The binding process triggers STING to traffic from the ER to the Golgi apparatus, where it is phosphorylated by the kinase TBK1. Phosphorylated STING serves as a docking site for the transcription factor IRF3, facilitating its phosphorylation by TBK1. Once phosphorylated, IRF3 forms dimers and translocates to the nucleus, where it drives the expression of type I interferons and pro-inflammatory cytokines, initiating a potent antimicrobial state. The DNA-sensing mechanism of cGAS is inherently non-selective regarding the origin of its ligand. It readily detects exogenous DNA from invading pathogens, thereby playing an indispensable role in host defense against microbial infections. However, this same mechanism also enables cGAS to recognize self-DNA that leaks from the nucleus or mitochondria into the cytosol under various cellular stress conditions. While critical for immunity, the recognition of self-dsDNA by cGAS can disrupt cellular homeostasis and trigger aberrant inflammatory responses. The loss of self-tolerance can precipitate or exacerbate the pathogenesis of autoimmune disorders such as systemic lupus erythematosus (SLE) and Aicardi-Goutières syndrome (AGS), highlighting the dual role of cGAS as both a sentinel for infection and a potential driver of autoimmune pathology. Notably, the subcellular localization of cGAS is not still. Increasing recent researches have revealed that cGAS is also abundant within the nucleus, challenging the traditional view of it solely as a cytosolic nucleic acid sensor. Within the nucleus, cGAS exhibits non-canonical functions that are distinct from its canonical immunological role. First, cGAS exists in a state of stringent immunological silence in the nucleus, with mechanisms involving its competitive binding to histones and its post-translational modifications which block the activation of cGAS enzymatic activity, thus, effectively preventing it from mounting an autoimmune attack on genomic DNA. Second, cGAS plays a critical role in maintaining genomic stability. Upon DNA damage, cGAS is rapidly recruited to the lesion site and participates in the DNA damage repair process. Moreover, under conditions of DNA replication stress, cGAS contributes to the stabilization of replication forks, preventing the cell from entering a state of uncontrolled hyper-replication. Consequently, in light of the dual role of cGAS in both immune regulation and tumor development, the development of small-molecule drugs targeting cGAS holds significant therapeutic promise. This review summarizes the structural characteristics of cGAS and its canonical function as a pattern recognition receptor in the cytosol, including the types of pathogens it recognizes and the autoimmune responses resulting from erroneous recognition of self-DNA. It then focuses on its emerging non-canonical functions within the nucleus, detailing its nucleocytoplasmic shuttling, the mechanisms underlying its nuclear immune quiescence, and its role in mediating DNA damage repair and replication fork stabilization. Finally, the review discusses the progress and application prospects of small-molecule drugs targeting cGAS for the treatment of autoimmune diseases and cancer.

Cyclic GMP-AMP synthase (cGAS), a pivotal molecule in innate immunity, has emerged as a keypoint in interdisciplinary research at the intersection of basic immunology and tumor biology. As a cytosolic nucleic acid sensor, cGAS is primarily characterized by its capacity to recognize double-stranded DNA (dsDNA) in the cytosol. Upon binding to dsDNA, cGAS undergoes a conformational change that promotes its dimerization and subsequent enzymatic activation. Once activated, it catalyzes the synthesis of the second messenger 2',3'-cGAMP from ATP and GTP. cGAMP then binds to the adaptor protein STING, which resides on the endoplasmic reticulum (ER) membrane. The binding process triggers STING to traffic from the ER to the Golgi apparatus, where it is phosphorylated by the kinase TBK1. Phosphorylated STING serves as a docking site for the transcription factor IRF3, facilitating its phosphorylation by TBK1. Once phosphorylated, IRF3 forms dimers and translocates to the nucleus, where it drives the expression of type I interferons and pro-inflammatory cytokines, initiating a potent antimicrobial state. The DNA-sensing mechanism of cGAS is inherently non-selective regarding the origin of its ligand. It readily detects exogenous DNA from invading pathogens, thereby playing an indispensable role in host defense against microbial infections. However, this same mechanism also enables cGAS to recognize self-DNA that leaks from the nucleus or mitochondria into the cytosol under various cellular stress conditions. While critical for immunity, the recognition of self-dsDNA by cGAS can disrupt cellular homeostasis and trigger aberrant inflammatory responses. The loss of self-tolerance can precipitate or exacerbate the pathogenesis of autoimmune disorders such as systemic lupus erythematosus (SLE) and Aicardi-Goutières syndrome (AGS), highlighting the dual role of cGAS as both a sentinel for infection and a potential driver of autoimmune pathology. Notably, the subcellular localization of cGAS is not still. Increasing recent researches have revealed that cGAS is also abundant within the nucleus, challenging the traditional view of it solely as a cytosolic nucleic acid sensor. Within the nucleus, cGAS exhibits non-canonical functions that are distinct from its canonical immunological role. First, cGAS exists in a state of stringent immunological silence in the nucleus, with mechanisms involving its competitive binding to histones and its post-translational modifications which block the activation of cGAS enzymatic activity, thus, effectively preventing it from mounting an autoimmune attack on genomic DNA. Second, cGAS plays a critical role in maintaining genomic stability. Upon DNA damage, cGAS is rapidly recruited to the lesion site and participates in the DNA damage repair process. Moreover, under conditions of DNA replication stress, cGAS contributes to the stabilization of replication forks, preventing the cell from entering a state of uncontrolled hyper-replication. Consequently, in light of the dual role of cGAS in both immune regulation and tumor development, the development of small-molecule drugs targeting cGAS holds significant therapeutic promise. This review summarizes the structural characteristics of cGAS and its canonical function as a pattern recognition receptor in the cytosol, including the types of pathogens it recognizes and the autoimmune responses resulting from erroneous recognition of self-DNA. It then focuses on its emerging non-canonical functions within the nucleus, detailing its nucleocytoplasmic shuttling, the mechanisms underlying its nuclear immune quiescence, and its role in mediating DNA damage repair and replication fork stabilization. Finally, the review discusses the progress and application prospects of small-molecule drugs targeting cGAS for the treatment of autoimmune diseases and cancer.

ObjectiveDonkey hide is the sole legally designated raw material for the preparation of the traditional Chinese medicine Ejiao. The quality stability of donkey hide during preservation directly determines the efficacy and safety of Ejiao. This study focuses on the dynamic succession of microbial communities during the preservation of donkey hides from different origins, aiming to clarify the correlation between microbial biodiversity difference and the degradation profiles of hide collagen and critical biochemical components, thereby providing a theoretical foundation for developing targeted preservation strategies based on microbial regulation. MethodsDonkey hides originating from four different regions were subjected to an accelerated microbial aging assay to simulate the spoilage process. The microbial community succession was analyzed using high-throughput sequencing. Microstructure changes and pore structure characteristics were assessed by scanning electron microscopy and mercury intrusion porosimetry, respectively. Additionally, the content of major components, including lipids, proteins, and sugars were determined by biochemical methods. ResultsAfter 96 h of aging, the collagen fiber structure in Africa donkey hides (ADH) exhibited significant degradation and collapse, followed by Xinjiang donkey hides (XDH). Instead, the microstructure of Dong’e black donkey hides (DDH) and Peru donkey hides (PDH) remained relatively intact. The porosities of DDH, XDH, PDH, and ADH increased from 27.9%, 15.7%, 30.3%, and 46.2% to 36.5%, 52.6%, 42.8%, and 57.7%, respectively, during the aging process, which suggested that the originally compact fiber structure was disrupted by microbial aging. Fourier transform infrared spectrometer analysis revealed the amide bands in XDH exhibited relatively weak intensity, and no collagen amide I band was observed in ADH. Meanwhile, the lipid and protein contents decreased in all four types of donkey hides, indicating that these components served as the primary nutrient sources for the growth of microorganism. Notably, the most severe collagen degradation was observed in XDH and ADH. A substantial increase was detected in the total soluble sugar in PDH aging solution and hydroxyproline in the ADH aging solution, respectively. These results indicated that donkey hides exhibit distinct patterns of structural degradation and nutrient utilization. Furthermore, the viable cells number of donkey hides increased sharply after 48 h of aging. Metagenomic analysis revealed that the relative abundance of Euryarchaeota in ADH, PDH and XDH declining from initial 93.19%, 97.73% and 30.08% to 0.79%, 1.43% and 0.02% after 96 h, respectively. Conversely, a significantly increase was observed in the abundance of Bacillota, with a marked increase in ADH, peaking at 92.75%. Additionally, the abundance of Pseudomonadota in PDH increased from 0.10% to 87.84%, suggesting that Bacillota and Pseudomonadota may be key factors exacerbating donkey hide spoilage. Unlike the other three types of donkey hides, the dominant bacterial phylum in DDH shifted from Pseudomonadota to Bacteroidota, characterized by a substantial abundance increase of Bacteroidota from 0.13% to 44.22%. ConclusionRegional variation in origin significantly influence the microbial aging of donkey hides, leading to distinct patterns of structural deterioration and differential nutrient utilization. Therefore, implementing origin-specific preservation strategies, through the precisely controlling environmental factors to suppress harmful phyla such as Bacillota and Pseudomonadota, is crucial for enhancing the storage quality of donkey hides.

Glycogen synthase 1 (GYS1) is the rate-limiting enzyme responsible for glycogen synthesis in skeletal muscle, heart, brain, and other extrahepatic tissues, playing a central role in systemic energy homeostasis. The human GYS1 gene maps to chromosome 19q13.33, comprises 16 exons, and encodes a 737-amino-acid polypeptide that is highly conserved across mammals. GYS1 activity is subject to multilayered and precisely coordinated regulation. At the transcriptional level, the GYS1 promoter contains a hypoxia response element (HRE) that mediates HIF-1α-dependent induction under low-oxygen conditions, as well as a muscle-specific enhancer harboring MEF2 and MyoD binding sites that confers tissue-restricted expression. At the post-translational level, a hierarchical phosphorylation cascade serves as the primary activity switch: glycogen synthase kinase 3β (GSK3β) sequentially phosphorylates four C-terminal serine residues following casein kinase II priming, while protein kinase A (PKA) and AMP-activated protein kinase (AMPK) provide parallel inhibitory inputs at both N- and C-terminal sites. Dephosphorylation and reactivation are mediated by protein phosphatase 1 (PP1) through tissue-specific glycogen-targeting regulatory subunits such as PPP1R3A and PPP1R3B, which anchor PP1 to glycogen particles and direct its activity toward GYS1. The allosteric activator glucose-6-phosphate (G6P) binds at the dimer interface, simultaneously enhancing catalytic efficiency and promoting dephosphorylation susceptibility, thereby establishing a feed-forward activation loop that couples substrate availability to glycogen synthesis. Beyond phosphorylation, GYS1 is regulated by ubiquitination (mediated by the E3 ligase PJA1), acetylation, O-linked β-N-acetylglucosamine (O-GlcNAc) modification, and SUMOylation, which collectively modulate protein stability, subcellular localization, and protein-protein interactions. Epigenetic mechanisms, including CpG island methylation and histone acetylation dynamics, govern chromatin accessibility at the GYS1 locus, while muscle-specific microRNAs such as miR-1 and miR-206 fine-tune GYS1 expression at the post-transcriptional level. Dysregulation of GYS1 has been identified as a central pathogenic driver in a spectrum of human diseases. In inherited glycogen storage disorders—including Lafora disease, adult polyglucosan body disease (APBD), and Pompe disease—loss of upstream regulatory control leads to GYS1 hyperactivation and the accumulation of structurally abnormal or excessive glycogen, resulting in progressive neurodegeneration, myopathy, and multiorgan dysfunction. In type 2 diabetes mellitus (T2DM), impaired insulin signaling through the PI3K-AKT-GSK3β axis maintains GYS1 in a hyperphosphorylated inactive state in skeletal muscle, compromising postprandial glucose disposal and exacerbating hyperglycemia. In oncology, GYS1 exhibits context-dependent roles across multiple cancer types. In hepatocellular carcinoma, FMO2⁺ cancer-associated fibroblasts stabilize GYS1 by competitively inhibiting PJA1-mediated ubiquitination, and stabilized GYS1 subsequently activates NF‑κB/CCL19 signaling to promote tertiary lymphoid structure formation and enhance anti-PD-1 immunotherapy responsiveness. In clear cell renal cell carcinoma, GYS1 promotes tumor progression through non-canonical NF‑κB pathway activation via the scaffold protein RPS27A. In triple-negative breast cancer, GYS1 has been identified as a trigger of disulfidptosis and an activator of NF-κB signaling through non-enzymatic facilitation of IκBα degradation. In colorectal cancer, mitochondrial fission deficiency drives AMPK-dependent GYS1 upregulation and glycogen accumulation as a compensatory survival mechanism, while in cervical cancer, GYS1-maintained glycogen reserves fuel the pentose phosphate pathway to generate NADPH for ROS clearance, thereby conferring cisplatin resistance in cancer stem cells. Therapeutic strategies targeting GYS1 have gained substantial momentum across these disease contexts. For glycogen storage disorders, antisense oligonucleotides, small interfering RNAs (e.g., ABX1100), and small-molecule inhibitors (e.g., MZ-101) have demonstrated preclinical and early clinical efficacy in reducing pathological glycogen accumulation. For T2DM, pharmacological activation of GYS1 through GSK3β inhibition or enhancement of PP1-mediated dephosphorylation is being explored to restore insulin-stimulated glycogen synthesis. In cancer, GYS1-directed interventions—including targeted silencing to sensitize tumors to chemotherapy and immune microenvironment modulation to enhance immunotherapy—represent emerging precision oncology approaches. This review provides a comprehensive and integrated account of GYS1 gene structure, tissue-specific distribution, regulatory networks, and pathogenic roles in metabolic disorders and malignancies, with the aim of establishing a theoretical framework for the development of GYS1-targeted precision therapies.

Objective:To study the transmission pathways among empirical policy guidance,innovation diffusion,and health demands,providing theoretical references and policy recommendations for local governments to accelerate the establishment of hierarchical medical system.Methods:Based on the public value theory,and employed policy intensity quantification model and mediation effect validation model to elucidate the specific impact mechanisms of policy guidance and innovation diffusion on health demand.Results:The regression coefficient of local government policy guidance on residents'emergency care demand was 0.677,the regression coefficient of local government policy guidance on treatment model innovation diffusion in hospitals was 0.374,and the regression coefficient of treatment model innovation diffusion in hospitals on residents'emergency care demand was 0.689.The mediating effect of treatment model innovation diffusion in hospitals accounted for 38.1%of the total effect.The mediating effect of treatment model innovation diffusion in municipal administrative divisions accounted for 68.6%of the total effect.Conclusions and Suggestions:Local government policy guidance had a significant positive impact on residents'emergency care demand,innovation diffusion played a mediating role between policy guidance and health demand.It is recommended that local governments should pay attention to the guiding role of public policies and improve the intensity of chest pain center policies,should play the role of innovation diffusion intermediaries and to promote treatment model innovation diffusion in hospitals and administrative divisions two paths.

Objective:This study aims to construct a monitoring index system for early child development(ECD)that is consistent with China's actual situation,to scientifically and systematically evaluate the level of ECD and service capacity in various regions.Methods:The study was predicated on the theoretical foundation of the Nutrition Care Framework(NCF).Indicators were initially selected through a literature review and focus group interviews.The evaluation indicators were then determined through two rounds of expert consultation utilising the Delphi method.The Priority Sequence Diagram Method(PSDM)was subsequently implemented to determine indicator weights.Results:The final framework encompasses six first-level indicators(good health,adequate nutrition,responsive caregiving,opportunities for learning,security and safety,and demand and investment),12 second-level indicators,and 31 third-level indicators.Conclusion:The ECD index system constructed in this study integrates macro,meso,and micro levels,emphasises cross-sectoral collaboration and attention to child caregivers,and incorporates equity indicators to measure regional disparities.The research outcomes provide a reference for quantitatively assessing the level of ECD and service capacity across various regions in China.By leveraging mechanisms for cross-sectoral collaboration and goal-oriented approaches,the study provides a framework for the allocation of resources to key areas,thus laying the foundation for the sustained implementation and resource assurance of the child-priority development strategy.

Aim Mouse model of myocardial hypertro-phy was established via intraperitoneal injection of iso-proterenol(ISO)in mice.This approach allows for an in-depth investigation into the pharmacological effects and mechanisms of action of emodin,offering novel in-sights and directions for the improvement of myocardial hypertrophy.Methods The mice were randomly di-vided into the following groups:control group(CON),emodin group(EMO),MAPK activator control group(EMO+Ani),model group(ISO),treatment group(ISO+EMO),and activator intervention group(ISO+EMO+Ani).After treatment with emodin and inter-vention with MAPK activator,the heart weight ratio and cardiac size of each group were observed.Hematoxy-lin-eosin(HE)staining was used to observe the patho-logical changes in cardiac tissue,and kits were utilized to measure the levels of GSH,LDH,and MDA in the serum.Western blot was employed to detect the protein expression levels of inflammatory and oxidative factors,as well as p-p38,p-ERK,p38,and ERK in cardiac tis-sue.Results Emodin can significantly inhibit the production of myocardial inflammatory and oxidative factors induced by ISO,thereby effectively alleviating the degree of myocardial hypertrophy and fibrosis.Af-ter the p38/ERK signaling pathway was specifically ac-tivated by farnesol,the improvement effect of emodin on myocardial hypertrophy was weakened.Further comparison revealed that,compared with the myocardi-al hypertrophy pathological model group,the pathologi-cal protein expression levels in the farnesol-treated group showed no significant difference,and were even higher in some indicators.Conclusion Emodin can effectively inhibit the release of inflammatory factors and improve the state of oxidative stress by modulating the p38/ERK signaling pathway,thereby exerting an ameliorative effect on myocardial hypertrophy.

BACKGROUND:Dexamethasone and hindlimb suspension are commonly used methods for modeling sarcopenia in animal experiments due to their short modeling time,ease of operation,and low cost.OBJECTIVE:To compare the differences in muscle mass,strength and functional phenotypes and molecular mechanisms between two mouse sarcopenia models induced by dexamethasone and hindlimb suspension.METHODS:Thirty male C57BL/6 mice were randomly divided into three groups(n=10 per group).The normal control group received no intervention.The dexamethasone group received daily intraperitoneal injections of 1 mg/kg/d dexamethasone sodium phosphate solution for 6 continuous days to establish sarcopenia models in mice,while mice in the hindlimb suspension group were suspended by tail harness for 16 hours,once per day,to establish sarcopenia models.Within 6 weeks after modeling,changes in body mass were monitored.After 6 weeks of modeling,mice were tested for limb grip strength,mobility(swimming test),skeletal muscle wet mass,and skeletal muscle pathological morphology.Expressions of skeletal muscle protein synthesis and catabolism indexes as well as the AMPK/FoXO3α signaling pathway were detected by RT-PCR and western blot.RESULTS AND CONCLUSION:(1)Two weeks after modeling,both dexamethasone and hindlimb suspension groups showed a significant decrease in body mass compared with the normal control group(P<0.001).After 6 weeks of modeling,grip strength of mice in both dexamethasone and hindlimb suspension groups was lower than that in the normal control group(P<0.001).The wet mass of gastrocnemius and extensor digitorum longus muscles and the cross-sectional area of gastrocnemius and soleus muscles in the dexamethasone group were lower than those in the normal control group(P<0.05).Compared with the hindlimb suspension group,the cross-sectional area of gastrocnemius muscle was significantly smaller in the dexamethasone group(P<0.05),while the cross-sectional area of soleus muscle was larger in the dexamethasone group(P<0.05).Mice in the dexamethasone group had reduced mobility when compared with those in the normal control group and the hindlimb suspension group(P<0.05).(3)Compared with the normal control group,PI3K,mTOR,AMPK,and PGC-1α mRNA expression and P-AMPK/AMPK protein were decreased in the two modeling groups(P<0.05),and FoXO3α mRNA expression and PGC-1α and FoXO3 protein expression were elevated(P<0.05);in the dexamethasone group,Akt1 mRNA expression was decreased(P<0.05),while Atrogin-1 and MuRF-1 mRNA expression was elevated(P<0.05);in the hindlimb suspension group,Akt1 mRNA expression was elevated(P<0.05).(4)Compared with the dexamethasone group,mTOR,Akt1,and FoXO3α mRNA expression was elevated in the hindlimb suspension group(P<0.05),while Atrogin-1 and MuRF-1 mRNA expression was decreased(P<0.05).To conclude,both modeling methods could decrease the levels of mitochondrial energy metabolism in skeletal muscle,with the dexamethasone group mediating atrophy of skeletal muscle through the dual action of ubiquitin proteasome and energy metabolism pathways,and the hindlimb suspension group inducing atrophy of skeletal muscle by mediating the energy metabolism pathway through the AMPK/FoXO3α signaling pathway,subsequently causing a reduction in mass,strength,and function of skeletal muscle.

Aim To predict the mechanism of action of ginsenoside Rg1(G-Rg1)paired with hirudin in the treatment of myocardial fibrosis in acute myocardial in-farction(AMI)based on the network pharmacology ap-proach,and to validate it by in vivo and in vitro experi-ments.Methods The corresponding targets of G-Rg1 and Hirudin were collected using SwissTargetPredic-tion,TargetNet,ETCM and ChEMBL databases,and the targets related to AMI and myocardial fibrosis were collected using GeneCards,OMIM and DisGeNET da-tabases.The drug-disease intersection targets were subjected to protein-protein interaction network(PPI)network analysis,gene ontology(GO)functional en-richment analysis and kyoto encyclopedia of genomes(KEGG)pathway enrichment analysis.Key targets and pathways were validated using an AMI mouse mod-el induced by ligation of the anterior descending branch of the left coronary artery in mice versus a hypoxia-in-duced injury model of human cardiac microvascular en-dothelial cells(HCMECs).Results G-Rg1 paired with hirudin had 229 drug targets,816 AMI and myo-cardial fibrosis disease targets,and 65 intersecting tar-gets.PPI analysis showed that tumor necrosis factor(TNF),interleukin-1[3(IL-1 β),transforming growth factor beta-1(TGF-β1),nuclear factor kappa-B(NF-κB),and interleukin-6(IL-6)might be the core tar-gets of G-Rg1 paired with Hirudin in the treatment of post-MI myocardial fibrosis;KEGG was enriched for a total of 141 pathways involving endocrine and metabo-lism,inflammation,and immunity,mainly TNF signa-ling pathway,PI3K/Akt signaling pathway and TGF-βsignaling pathway.In vivo experiments confirmed that G-Rg1 paired with hirudin attenuated myocardial fibro-sis after AMI in mice,and down-regulated the expres-sion of TNF-α,IL-1β,NF-κB,TGF-β1,and Smad2/3 proteins in myocardial tissues.In vitro experiments confirmed that G-Rg1 paired with Hirudin inhibited cellular NF-κB/TGF-β1 pathway,reduced hypoxia-in-duced cellular TNF-α and IL-1β expression,and su-perimposed NF-κB inhibitor significantly reduced IL-1 β expression and attenuated cellular inflammatory re-sponse.Conclusions G-Rg1 with Hirudin treats post-MI myocardial fibrosis by regulating TNF-α,IL-1 β and other targets and NF-KB/TGF-β1 pathway,reflecting its multi-pathway and multi-target action characteris-tics,and providing a pharmacological basis for the treatment of post-MI myocardial fibrosis with G-Rg1 with Hirudin.

Aim To study the mechanism of adipose mesenchymal stem cell exosomes(ASC-exo)inhibition of fluorescein isothiocyanate(FITC)-induced atopic dermatitis(AD).Methods The mouse age,extrac-tion method,and the concentration of a solution of typeⅠ collagen enzyme and other conditions were compared to study the effects on the morphology and quantity of adipose mesenchymal stem cells(ASCs)after extrac-ted.FITC-induced mouse model in vivo was estab-lished and different doses of ASC-exo were given to measure ear thickness,ear weight and ear scratching times of mice.HE staining was used to observe the pathological changes of ear tissue of mice.The non-toxicity of ASC-exo was detected.IgE,IL-5,IL-13 and other cytokines were detected by ELISA.The gene ex-pressions of TSLP,IL-33,occludin,Claudin-1(CLDN-1)and E-cadherin were detected by RT-qPCR.The protein expression was detected by immunohistochemis-try.Results An efficient method for extracting ASCs was established.Compared with the blank group,mice in the model group showed obvious AD symptoms.Compared with the model group,ASC-exo administra-tion group significantly reduced the number of ear scratches,epidermal thickening,inflammatory cell infil-tration and the secretion of Th2 cytokines IL-5 and IL-13.Meanwhile,ASC-exo administration group signifi-cantly increased the expression of structural proteins CLDN-1 and occludin in epithelial cells and decreased the expression of TSLP and IL-33.Conclusions ASC-exo can significantly improve Th2 skin inflamma-tion in AD mice,and its mechanism may be through in-creasing the expression of tight junction proteins and adhesion link protein in epithelial cells,repairing the skin barrier,and inhibiting the key promoters of allergy TSLP and IL-33.