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.

Hepatic fibrosis is a key pathological process in the development of chronic liver disease to cirrhosis, and its core mechanism involves the activation of hepatic stellate cells(HSC) and abnormal deposition of extracellular matrix(ECM). Although existing treatments, such as antiviral drugs, can delay disease progression, they have the problem of single therapeutic targets and cannot reverse fibrosis. Accordingly, multidimensional intervention strategies are urgently needed. Recent studies have shown that circadian rhythm disorders aggravate hepatic fibrosis by regulating metabolism, immunity, and inflammation. Traditional Chinese medicine(TCM) plays a unique role in restoring the circadian clock via multi-target and holistic regulation. This paper establishes a three-dimensional network by systematically integrating biological clock, metabolism, and immunity for the first time to elucidate the scientific connotation of the theory of time-concerned treatment of TCM, and proposes a new strategy for the development of time-targeted compound prescriptions, providing innovative ideas for the treatment of hepatic fibrosis.
Humans ; Liver Cirrhosis/metabolism* ; Drugs, Chinese Herbal/therapeutic use* ; Circadian Rhythm/drug effects* ; Animals ; Medicine, Chinese Traditional ; Hepatic Stellate Cells/drug effects*

Modified electro-convulsive therapy (MECT) is one of the most potent treatments for major depressive disorder (MDD). However, it remains a second-line option due to significant side effects, such as transient memory loss. The relationship between therapeutic efficacy and cognitive impairment warrants further investigation to develop improved treatment regimens. In this review, we examine recent evidence from magnetic resonance imaging (MRI) studies aiming to identify structural and functional brain changes specifically associated with both the antidepressant effects and the amnesic outcomes of MECT. MECT induces widespread alterations across multiple brain systems. Increases in gray matter volume (GMV) have been observed in the prefrontal, temporal, and parietal cortices, as well as in subcortical regions such as the hippocampus (HP), amygdala, and striatum. Strengthening of myelination has also been reported along the dorsolateral prefrontal-limbic pathways. Functional changes include increased spontaneous neural activity in prefrontal areas, reorganization of intrinsic connectivity within the default mode network (DMN), and altered functional connectivity (FC) among the DMN, salience network (SN), and central executive network (CEN). Correlational studies have identified structural and functional alterations linked to antidepressant efficacy, including right hippocampal volume enlargement, prefrontal cortical thickening, reduced iron deposition in the striatum, decreased FC within certain DMN nodes, and enhanced effective connectivity from the dorsolateral prefrontal cortex (DLPFC) to the right angular gyrus. In contrast, the amnesic effects have been associated with increased volumes in the left hippocampus and bilateral dentate gyrus; enhanced FC in the left angular gyrus and left posterior cingulate cortex (PCC); increased FC between the right ventral anterior insula and DLPFC; and reduced FC in the left thalamus and bilateral precuneus. Changes in the hippocampus appear to correlate with both antidepressant efficacy and memory impairment. Clinical studies have found no significant correlation between the severity of memory impairment and the reduction in depressive symptoms, suggesting that the therapeutic and adverse effects may arise from distinct regional or subregional mechanisms. Supporting this hypothesis, recent findings show that increased right hippocampal volume is significantly associated with reduced depression scores, whereas increased volume in the left dentate gyrus correlates with declines in delayed recall performance. Additionally, enhanced connectivity between the anterior hippocampus and middle occipital gyrus (MOG) has been linked to mood improvement, while decreased FC between the mid-hippocampus and angular gyrus has been associated with impairments in memory integration. In conclusion, current evidence suggests that the antidepressant and memory-impairing effects of MECT may localize to distinct hippocampal subregions. These effects likely result from differential modulation of local neural activity and functional connectivity, leading to divergent behavioral outcomes. Given that both effects may originate in deep and spatially constrained structures such as the hippocampus, small-sample studies and conventional methodologies may fail to differentiate them effectively. Future research should employ large-scale, longitudinal designs utilizing high-field MRI and multimodal neuroimaging to characterize MECT-induced structure-function coupling in the hippocampus and its integration at the network level. Additionally, multiscale analyses spanning molecular, circuit, and network dimensions would be beneficial.

Objective To evaluate the role and potential mechanism of apolipoprotein E(APOE)in drug resistance of colon cancer by bioinformatic tools and cellular experiments.Methods After downloading the microarray dataset GSE196900 from the GEO database,the online tool GEO2R was used to identify genes that were expressed differently in the drug-resistant and control groups.The differently expressed genes were then examined for Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment.The STRING database and Cytoscape software were used to build protein-protein interaction(PPI)networks and find hub genes.Hub genes'predictive significance in colon cancer was further assessed.Western blod and qRT-PCR were used to identify changes in APOE expression,whereas Transwell was used to identify changes in the colon cancer cells'capacity for invasion and migration.Results The analysis of GO and KEGG enrichment revealed that the differential genes derived from the GSE196900 dataset were primarily focused on receptor-ligand activity and cytokine-cytokine receptor interaction pathways.Using the CytoNCA plug-in in Cytoscape software,ten hub genes were obtained through PPI construction.Of these,the prognosis of the patients with colon cancer was negatively correlated with the expression of the APOE gene(P<0.05)and the overexpression of the APOE gene might significantly increase the migration and nvasivenessability of colon cancer cells(P<0.05).Conclusion The increased expression of APOE significantly promotes the migration and invasion ability of colon cancer cells,which may be one of the mechanisms by which APOE gene promotes tumor progression in the patients with colon cancer.

Objective:To explore the predictive value of serum interleukin-6(IL-6)combined with Montreal Cognitive Assessment(MoCA)score and CHANGE risk score for post-stroke cognitive impairment(PSCI),and to provide a basis for early identification and intervention of high-risk patients.Methods:The general data of 200 patients with acute stroke who were admitted to our hospital from October 2022 to September 2024 were retrospectively analyzed,they were divided into PSCI group(49 cases)and non PSCI group(151 cases)based on whether PSCI occurred 3 months after acute stroke.The general data of two groups were compared,multiple logistic regression was used to analyze the influencing factors of PSCI,and receiver operating characteristic(ROC)curves were used to evaluate predictive efficiency of serum IL-6,MoCA score and CHANGE risk score for of PSCI.Results:There was a statistically significant difference in age and education level between the two groups(P＜0.05).The serum IL-6 level and CHANGE risk score in the PSCI group were higher than those in the non PSCI group,while the MoCA score was lower than that in the non PSCI group(P＜0.05).Multivariate logistic regression showed that elevated IL-6 levels(OR=1.851,P=0.001)and elevated CHANGE risk scores(OR=1.076,P=0.016)were independent risk factors of the occurrence of PSCI,while elevated in MoCA score(OR=0.806,P=0.001)was a protective factor(P＜0.05).IL-6 levels,MoCA scores and CHANGE risk scores have high predictive efficiency for the occurrence of PSCI,the area under the curve(AUC)for predicting occurrence of PSCI by the three alone were 0.783,0.825 and 0.857 respectively,the AUC for the combined detection of the three indicators was 0.912,significantly higher than that of each indicator detected separately.Conclusion:Elevated serum IL-6,decreased MoCA score and increased CHANGE risk score are risk factors for PSCI,the combined detection model of the three has the highest predictive efficiency for occurrence of PSCI and can provide scientific basis for early clinical intervention.

Objective:To explore the predictive value of serum interleukin-6(IL-6)combined with Montreal Cognitive Assessment(MoCA)score and CHANGE risk score for post-stroke cognitive impairment(PSCI),and to provide a basis for early identification and intervention of high-risk patients.Methods:The general data of 200 patients with acute stroke who were admitted to our hospital from October 2022 to September 2024 were retrospectively analyzed,they were divided into PSCI group(49 cases)and non PSCI group(151 cases)based on whether PSCI occurred 3 months after acute stroke.The general data of two groups were compared,multiple logistic regression was used to analyze the influencing factors of PSCI,and receiver operating characteristic(ROC)curves were used to evaluate predictive efficiency of serum IL-6,MoCA score and CHANGE risk score for of PSCI.Results:There was a statistically significant difference in age and education level between the two groups(P＜0.05).The serum IL-6 level and CHANGE risk score in the PSCI group were higher than those in the non PSCI group,while the MoCA score was lower than that in the non PSCI group(P＜0.05).Multivariate logistic regression showed that elevated IL-6 levels(OR=1.851,P=0.001)and elevated CHANGE risk scores(OR=1.076,P=0.016)were independent risk factors of the occurrence of PSCI,while elevated in MoCA score(OR=0.806,P=0.001)was a protective factor(P＜0.05).IL-6 levels,MoCA scores and CHANGE risk scores have high predictive efficiency for the occurrence of PSCI,the area under the curve(AUC)for predicting occurrence of PSCI by the three alone were 0.783,0.825 and 0.857 respectively,the AUC for the combined detection of the three indicators was 0.912,significantly higher than that of each indicator detected separately.Conclusion:Elevated serum IL-6,decreased MoCA score and increased CHANGE risk score are risk factors for PSCI,the combined detection model of the three has the highest predictive efficiency for occurrence of PSCI and can provide scientific basis for early clinical intervention.

Objective To develop a time-resolved fluorescent immunoassay kit for the rapid,accurate and quantitative detection of S100B protein in serum and to evaluate its performance.Methods The test strip was prepared using time-resolved fluorescent microsphere-labeled anti-S100B polyclonal antibody and rabbit IgG antibody,labeling pads,sample pads,S100B nitrocellulose films and absorbent paper,and an S100B time-resolved fluorescence immunoassay kit was obtained by assembling the cartridge.The performance of the kit developed was evaluated by standard curve,accuracy,minimum detection limit,linear interval,specificity,reproducibility and stability.The reference intervals of 199 pieces of healthy human serum and plasma samples from a certain region were detected with the kit,and the clinical performance of the kit and Roche Elecsys S100 kit was tested by synchronous blind method to assess the consistency of the results of the two kits for 142 samples.Results The S100B time-resolved fluorescence immunoassay kit had the standard curve beingy=(1.133 02+1.752 24)/[1+(x/1.082 20)×(-0.603 52)]-1.752 24,R2=0.999 08 and the linear range being[0.05,30]ng/mL,which met the requirements of the relative deviation of the accuracy within±15％,the minimum detection limit not hgier than 0.05 ng/mL,the relative deviation of specificity within±15％and the coefficient of variation of intra-and inter-batch difference less than 15％.The stability test results indicated that the kit was valid for 12 months at 2-30 ℃ conditions.The reference intervals of serum and plasma samples measured by the kit were both lower than 0.3 ng/mL.Clinical trials showed that the results by the kit and Roche Elecsys S100 Assay Kit were in high agreement(Kappa=0.906 1＞0.80)and met the requirements.Conclusion The kit developed detects the concentration of S100B protein in serum quickly,accurately and quantitatively,and provides references for the diagnosis and treatment of neurological diseases,autoimmune diseases,cerebrovascular diseases and etc.[Chinese Medical Equipment Journal,2024,45(1):47-55]

Aim To investigate the protective effect of Jujing formula on retina of mice with dry age-related macular degeneration(AMD).Methods The mouse model of dry AMD was induced by intraperitoneal in-jection of sodium iodate,and the prognosis was given to the Jujing formula.Retinal thickness was detected by optical coherence tomography(OCT),the retinal morphological changes were observed by hematoxylin-eosin(HE)staining,and the apoptosis of retinal cells was detected by in situ terminal transferase labeling(TUNEL)staining.Combination of tumor necrosis fac-tor-α(TNF-α),interleukin-6(IL-6)and interleukin-1β(IL-1 β)in eyeballs and serum,superoxide dis-mutase(SOD),glutathione(GSH)and malondialde-hyde(MDA)were evaluated to assess the protective effects of Jujing formula on retinal injury in mice with dry AMD.Results The results of OCT,HE and TUNEL staining showed that Jujing formula significant-ly improved the retinal injury induced by sodium iodate in mice with dry AMD,increased the retinal thickness(P＜0.05),reduced the apoptosis of retinal cells(P＜0.01),and increased the levels of GSH,IL-6 and SOD activity in eyeballs and serum(P＜0.01).The levels of TNF-α,IL-6,IL-1β and MDA were reduced(P＜0.01).Conclusions Jujing formula has certain therapeutic effects on retinal injury in dry AMD,which may be related to inhibiting inflammatory response and enhancing antioxidant capacity.

This study aims to observe the effects of different doses of Astragali Radix on the expression of glucagon(GLP-1) in se-rum and glucagon receptor(GLP-1R) in cartilage tissue in rats with knee osteoarthritis(KOA), explore the effect of Astragali Radix on the inflammation and apoptosis of KOA by regulating GLP-1/GLP-1R signaling axis, and investigate the mechanism of its action in alleviating KOA. Forty-eight male SD rats were randomly divided into six groups: blank group, model group, low-, medium-, and high-dose Astragali Radix groups(3.125, 6.25, and 12.5 g·kg~(-1)), and glucosamine sulfate group(0.1 g·kg~(-1)). Except for the blank group, rats in other groups were injected with sodium iodoacetate(MIA) into the knee joint to establish KOA models. After successful modeling, the rats were continuously treated for five weeks. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of GLP-1, tumor necrosis factor-alpha(TNF-α), and interleukin-1β(IL-1β) in rat serum. Pathological examination was utilized to observe the pathological changes in knee joint cartilage. The mRNA levels of TNF-α and MMP13 in knee joint cartilage were detected by qRT-PCR, and the protein expression levels of GLP-1R, MMP13, and caspase-8 in knee joint cartilage were detected by Western blot. The expression of GLP-1R and MMP13 in the knee joint was detected by immunohistochemistry. Tunel staining was used to observe the apoptosis of chondrocytes in the knee joint. The above experimental results showed that Astragali Radix may raise the serum levels of GLP-1, reduce serum levels of TNF-α and IL-1, and decrease the relative mRNA expression of TNF-α and MMP13 through the GLP-1/GLP-1R axis. It thus activated GLP-1R, reduced the protein expression of MMP13 and caspase-8 in cartilage, and regulated their related signaling pathways to improve inflammation and apoptosis, so as to protect cartilage and improve KOA.
Animals ; Male ; Rats, Sprague-Dawley ; Osteoarthritis, Knee/genetics* ; Rats ; Drugs, Chinese Herbal/pharmacology* ; Glucagon-Like Peptide 1/metabolism* ; Glucagon-Like Peptide-1 Receptor/metabolism* ; Astragalus propinquus/chemistry* ; Humans ; Matrix Metalloproteinase 13/metabolism* ; Signal Transduction/drug effects* ; Tumor Necrosis Factor-alpha/metabolism* ; Astragalus Plant/chemistry* ; Apoptosis/drug effects*