1.cGAS: Its Canonical and Non-canonical Functions
Wen-Xian ZHENG ; Meng-Jie XIONG ; Shu-Ting JIA ; Ruo-Yu ZHOU
Progress in Biochemistry and Biophysics 2026;53(5):1279-1296
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.
2.cGAS: Its Canonical and Non-canonical Functions
Wen-Xian ZHENG ; Meng-Jie XIONG ; Shu-Ting JIA ; Ruo-Yu ZHOU
Progress in Biochemistry and Biophysics 2026;53(5):1279-1296
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.
3.Design and performance verification of high altitude adaptive oxygen generator
Bo WANG ; Xiao-feng LIU ; Wen-jia LIU ; Yi LI ; Ya-nan WU ; Shu-jie CUI ; Wei ZHANG
Chinese Medical Equipment Journal 2025;46(4):29-34
Objective To design a high altitude adaptive oxygen generator for the crews to alleviate their high altitude reaction in high altitude environment and meet their requirements for oxygen supply.Methods A high altitude adaptive oxygen generator based on the mature pressure swing adsorption oxygen production method was designed with the key technologies of discharge capacity compensation of air compression pump and airway fusion of molecular sieve tower,which had the components of molecular sieve tower,air compression pump,controller,cooling fan,cooler,solenoid valve,regulator,flow meter and etc.Trials were carried out at the simulated altitude and field plateau environment so as to verify the high altitude adaptive performance of the oxygen generator developed.Results The trial results showed the oxygen generator met the desired objectives and the requirements for oxygen volume fraction in GJB 2799-1996 General specification for medical oxygen generator using molecular sieve method.Conclusion The oxygen generartor provides oxygen supply effectively for vehicle operators in plateau environments or the ones rushing into the plateau.[Chinese Medical Equipment Journal,2025,46(4):29-34]
4.Effects of Huazhuo Jiedu Shugan Formula on ameliorating learning and memory impairment in a rat model of vascular dementia via SIRT1/PGC-1α/PPARγ pathway
Chi WANG ; Shu-jie SUN ; Jia LIU ; Cong LI ; Ye LU ; Lin PEI
Chinese Traditional Patent Medicine 2025;47(3):782-789
AIM To investigate the effects of Huazhuo Jiedu Shugan Formula(HJSGF)on improving learning and memory impairment in a rat model of vascular dementia(VD)via SIRT1/PGC-1α/PPARγ pathway.METHODS The SD rats were randomly divided into the sham control group,the model group,the donepezil group(0.5 mg/kg),and the low-,medium-and high-dose HJSGF groups(2.7,5.4,10.8 g/kg),with 10 rats in each group.The VD rat models established by bilateral common carotid artery permanent ligation(2-VO)had their neurological behavior assessment using the Longa5-point scale,and their modeling success confirmed by the Morris water maze test and their 3-week corresponding dosing of drugs by gavage afterward.After the drug administration,the rats had their spatial memory ability tested through behavioral experiments;their serum levels of IL-18 and IL-1β measured by ELISA;their histopathological changes and neuronal morphology in the hippocampal CA1 region observed by HE staining and Nissl staining;and their hippocampal protein expressions of SIRT1,PGC-1α and PPARγ detected by immunohistochemistry and Western blot.RESULTS Compared with the sham control group,the model group showed prolonged escape latency(P<0.01);decreased platform crossing times and target quadrant residence time(P<0.01);disorganized arrangement of hippocampal CA1 neurons,nuclear condensation,reduced Nissl bodies,increased secretion and protein expressions of IL-1β and IL-18(P<0.01);and reduced hippocampal protein expressions of SIRT1,PGC-1α and PPARγ(P<0.01).Compared with the model group,the groups intervened with donepezil or HJSGF showed shortened escape latency(P<0.05,P<0.01);increased platform crossing times and target quadrant residence time(P<0.05,P<0.01);alleviated damage of the hippocampal CA1 region,reduced secretion and protein expressions of IL-1β and IL-18(P<0.05,P<0.01);and elevated hippocampal protein expressions of SIRT1,PGC-1α and PPARγ(P<0.05,P<0.01).CONCLUSION HJSGF may alleviate the inflammatory responses in VD rats and therefore improve their learning and memory impairment by activating the SIRT1/PGC-1α/PPARγ signaling pathway.
5.Design and performance verification of high altitude adaptive oxygen generator
Bo WANG ; Xiao-feng LIU ; Wen-jia LIU ; Yi LI ; Ya-nan WU ; Shu-jie CUI ; Wei ZHANG
Chinese Medical Equipment Journal 2025;46(4):29-34
Objective To design a high altitude adaptive oxygen generator for the crews to alleviate their high altitude reaction in high altitude environment and meet their requirements for oxygen supply.Methods A high altitude adaptive oxygen generator based on the mature pressure swing adsorption oxygen production method was designed with the key technologies of discharge capacity compensation of air compression pump and airway fusion of molecular sieve tower,which had the components of molecular sieve tower,air compression pump,controller,cooling fan,cooler,solenoid valve,regulator,flow meter and etc.Trials were carried out at the simulated altitude and field plateau environment so as to verify the high altitude adaptive performance of the oxygen generator developed.Results The trial results showed the oxygen generator met the desired objectives and the requirements for oxygen volume fraction in GJB 2799-1996 General specification for medical oxygen generator using molecular sieve method.Conclusion The oxygen generartor provides oxygen supply effectively for vehicle operators in plateau environments or the ones rushing into the plateau.[Chinese Medical Equipment Journal,2025,46(4):29-34]
6.Analysis of China's cross-regional medical insurance settlement policy based on policy tools
Shi-qiang WANG ; Hui WANG ; Shu ZHANG ; Zi-qi ZHANG ; Yi-jie LI ; Jia-yi LIU ; Guo-heng HU
Chinese Journal of Health Policy 2025;18(10):32-39
Objective:Systematically review the release status and characteristics of policies related to cross-regional medical insurance settlement policies in China,providing reference for promoting the convenience of medical insurance settlement services and improving management efficiency.Methods:Using content analysis,a two-dimensional framework of"policy objectives-policy tools"was constructed.A total of 127 policy documents were coded and analyzed.Results:Demand-based tools were applied most frequently(43.6%),followed by environmental and supply-based tools.Policy objectives mainly focused on improving service convenience,supported by expanding coverage and ensuring regulatory security.Conclusions:China's cross-regional medical insurance settlement policies have improved service accessibility and strengthened institutional supervision while gradually expanding coverage.However,deficiencies remain in assessment refinement and emergency mechanisms.Greater interdepartmental coordination is needed to enhance regulatory linkage and ensure the safe operation of medical insurance funds.
7.Analysis of China's cross-regional medical insurance settlement policy based on policy tools
Shi-qiang WANG ; Hui WANG ; Shu ZHANG ; Zi-qi ZHANG ; Yi-jie LI ; Jia-yi LIU ; Guo-heng HU
Chinese Journal of Health Policy 2025;18(10):32-39
Objective:Systematically review the release status and characteristics of policies related to cross-regional medical insurance settlement policies in China,providing reference for promoting the convenience of medical insurance settlement services and improving management efficiency.Methods:Using content analysis,a two-dimensional framework of"policy objectives-policy tools"was constructed.A total of 127 policy documents were coded and analyzed.Results:Demand-based tools were applied most frequently(43.6%),followed by environmental and supply-based tools.Policy objectives mainly focused on improving service convenience,supported by expanding coverage and ensuring regulatory security.Conclusions:China's cross-regional medical insurance settlement policies have improved service accessibility and strengthened institutional supervision while gradually expanding coverage.However,deficiencies remain in assessment refinement and emergency mechanisms.Greater interdepartmental coordination is needed to enhance regulatory linkage and ensure the safe operation of medical insurance funds.
8.Effects of Huazhuo Jiedu Shugan Formula on ameliorating learning and memory impairment in a rat model of vascular dementia via SIRT1/PGC-1α/PPARγ pathway
Chi WANG ; Shu-jie SUN ; Jia LIU ; Cong LI ; Ye LU ; Lin PEI
Chinese Traditional Patent Medicine 2025;47(3):782-789
AIM To investigate the effects of Huazhuo Jiedu Shugan Formula(HJSGF)on improving learning and memory impairment in a rat model of vascular dementia(VD)via SIRT1/PGC-1α/PPARγ pathway.METHODS The SD rats were randomly divided into the sham control group,the model group,the donepezil group(0.5 mg/kg),and the low-,medium-and high-dose HJSGF groups(2.7,5.4,10.8 g/kg),with 10 rats in each group.The VD rat models established by bilateral common carotid artery permanent ligation(2-VO)had their neurological behavior assessment using the Longa5-point scale,and their modeling success confirmed by the Morris water maze test and their 3-week corresponding dosing of drugs by gavage afterward.After the drug administration,the rats had their spatial memory ability tested through behavioral experiments;their serum levels of IL-18 and IL-1β measured by ELISA;their histopathological changes and neuronal morphology in the hippocampal CA1 region observed by HE staining and Nissl staining;and their hippocampal protein expressions of SIRT1,PGC-1α and PPARγ detected by immunohistochemistry and Western blot.RESULTS Compared with the sham control group,the model group showed prolonged escape latency(P<0.01);decreased platform crossing times and target quadrant residence time(P<0.01);disorganized arrangement of hippocampal CA1 neurons,nuclear condensation,reduced Nissl bodies,increased secretion and protein expressions of IL-1β and IL-18(P<0.01);and reduced hippocampal protein expressions of SIRT1,PGC-1α and PPARγ(P<0.01).Compared with the model group,the groups intervened with donepezil or HJSGF showed shortened escape latency(P<0.05,P<0.01);increased platform crossing times and target quadrant residence time(P<0.05,P<0.01);alleviated damage of the hippocampal CA1 region,reduced secretion and protein expressions of IL-1β and IL-18(P<0.05,P<0.01);and elevated hippocampal protein expressions of SIRT1,PGC-1α and PPARγ(P<0.05,P<0.01).CONCLUSION HJSGF may alleviate the inflammatory responses in VD rats and therefore improve their learning and memory impairment by activating the SIRT1/PGC-1α/PPARγ signaling pathway.
9.Alleviation of hypoxia/reoxygenation injury in HL-1 cells by ginsenoside Rg_1 via regulating mitochondrial fusion based on Notch1 signaling pathway.
Hui-Yu ZHANG ; Xiao-Shan CUI ; Yuan-Yuan CHEN ; Gao-Jie XIN ; Ce CAO ; Zi-Xin LIU ; Shu-Juan XU ; Jia-Ming GAO ; Hao GUO ; Jian-Hua FU
China Journal of Chinese Materia Medica 2025;50(10):2711-2718
This paper explored the specific mechanism of ginsenoside Rg_1 in regulating mitochondrial fusion through the neurogenic gene Notch homologous protein 1(Notch1) pathway to alleviate hypoxia/reoxygenation(H/R) injury in HL-1 cells. The relative viability of HL-1 cells after six hours of hypoxia and two hours of reoxygenation was detected by cell counting kit-8(CCK-8). The lactate dehydrogenase(LDH) activity in the cell supernatant was detected by the lactate substrate method. The content of adenosine triphosphate(ATP) was detected by the luciferin method. Fluorescence probes were used to detect intracellular reactive oxygen species(Cyto-ROS) levels and mitochondrial membrane potential(ΔΨ_m). Mito-Tracker and Actin were co-imaged to detect the number of mitochondria in cells. Fluorescence quantitative polymerase chain reaction and Western blot were used to detect the mRNA and protein expression levels of Notch1, mitochondrial fusion protein 2(Mfn2), and mitochondrial fusion protein 1(Mfn1). The results showed that compared with that of the control group, the cell activity of the model group decreased, and the LDH released into the cell culture supernatant increased. The level of Cyto-ROS increased, and the content of ATP decreased. Compared with that of the model group, the cell activity of the ginsenoside Rg_1 group increased, and the LDH released into the cell culture supernatant decreased. The level of Cyto-ROS decreased, and the ATP content increased. Ginsenoside Rg_1 elevated ΔΨ_m and increased mitochondrial quantity in HL-1 cells with H/R injury and had good protection for mitochondria. After H/R injury, the mRNA and protein expression levels of Notch1 and Mfn1 decreased, while the mRNA and protein expression levels of Mfn2 increased. Ginsenoside Rg_1 increased the mRNA and protein levels of Notch1 and Mfn1, and decreased the mRNA and protein levels of Mfn2. Silencing Notch1 inhibited the action of ginsenoside Rg_1, decreased the mRNA and protein levels of Notch1 and Mfn1, and increased the mRNA and protein levels of Mfn2. In summary, ginsenoside Rg_1 regulated mitochondrial fusion through the Notch1 pathway to alleviate H/R injury in HL-1 cells.
Ginsenosides/pharmacology*
;
Receptor, Notch1/genetics*
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Signal Transduction/drug effects*
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Mice
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Animals
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Mitochondrial Dynamics/drug effects*
;
Mitochondria/metabolism*
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Cell Line
;
Reactive Oxygen Species/metabolism*
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Oxygen/metabolism*
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Cell Hypoxia/drug effects*
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Cell Survival/drug effects*
;
Membrane Potential, Mitochondrial/drug effects*
;
Humans
10.Application of OpenSim musculoskeletal model in biomechanics research of orthopedics and traumatology.
Rui LI ; Yang LIU ; Zhao-Jie ZHANG ; Xin-Wei ZHANG ; Yan-Zhen ZHANG ; Yan-Qi HU ; Can YANG ; Shu-Shi MAO ; Jia-Ming QIU
China Journal of Orthopaedics and Traumatology 2025;38(3):319-324
OpenSim is an open source, free motion simulation and gait analysis software, which can be used to dynamically simulate and analyze the complex motion of the human body, and is widely used in human biomechanical research. Since OpenSim can analyze multi-dimensional motion data such as muscle strength, joint torque, and muscle synergistic activation during human movement, it can be used to study the biomechanical mechanism of musculoskeletal imbalance diseases and various treatment methods in TCM orthopedics, and has a broad application prospect in the field of TCM orthopedics. By the analysis of the basic characteristics, elements, analysis process, and application prospects of OpenSim, it is concluded that OpenSim musculoskeletal model has a large application space in the field of traditional Chinese medicine orthopedic, which is helpful to explain the pathogenesis and mechanism of diseases, and promote the precision diagnosis and treatment of orthopedics diseases;the application of OpenSim musculoskeletal model can solve the problem that the previous research paid attention to the bone malalignment and not enough attention to the tendon, and provide a new method for the research of orthopedic diseases. At present, there are still problems in the promotion and application of OpenSim, such as large equipment requirements and high operation threshold. Therefore, multidisciplinary cooperation, clinical research, and data sharing are the basic research strategies in this field.
Humans
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Biomechanical Phenomena
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Orthopedics
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Traumatology
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Software
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Medicine, Chinese Traditional
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Musculoskeletal System
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Models, Biological

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