LIU Wansu， as the foremost of the four great masters of the Jin-Yuan period， established the "theory of fire-heat'' and extended the fire-heat pathogenesis framework to the field of stroke， thereby forming the theory of ''fire-heat inducing stroke''. This achieved a paradigmatic shift in stroke etiology from ''exogenous wind inducing stroke'' to ''fire-heat inducing stroke''. This paper systematically reviews the developmental trajectory of LIU Wansu's ''fire-heat inducing stroke'' theory and explores the social background， academic origins， and core connotations of its theoretical construction. The study found that， based on the ''Nineteen Pathomechanisms'' in the Huangdi's Internal Classic （Huang Di Nei Jing） and combined with clinical practice， LIU Wansu proposed that fire-heat is the fundamental cause of stroke， and that the Six Climatic Factors and the Five Zhi-Emotions can all transform into fire. He further constructed a stratified syndrome differentiation and therapeutic system centered on clearing heat and purging fire， emphasizing differentiated treatment of exterior and interior syndromes， Six Meridians syndrome differentiation， and seasonally adjusted medication. This theory not only resolved the diagnostic and therapeutic dilemmas of febrile epidemic diseases during the Jin-Yuan period， but also exerted a profound influence on later physicians such as ZHANG Zihe and ZHU Danxi， thereby promoting the pluralistic development of stroke theory in traditional Chinese medicine （TCM）. Modern pharmacological research provides solid scientific evidence， confirming that the ''fire-heat'' pathological state is highly associated with key mechanisms such as excessive inflammatory responses， oxidative stress， and excitatory amino acid toxicity following cerebral ischemia. Heat-clearing and fire-purging prescriptions and agents， such as Huanglian Jiedu Tang and baicalin， can exert multi-target neuroprotective effects by regulating inflammatory signaling， enhancing antioxidant enzyme activity， and balancing neurotransmitters. This not only verifies the scientific basis of the ''fire-heat inducing stroke'' theory from a modern biological perspective but also provides conclusive evidence for the clinical application of heat-clearing and fire-purging therapy. LIU Wansu's ''fire-heat inducing stroke'' theory represents a major milestone in the historical understanding of stroke pathogenesis， and its academically transitional insights continue to hold core guiding value for the pattern identification and treatment of ischemic stroke today.

ObjectiveTo investigate whether Huanglian Jiedutang can inhibit neutrophil infiltration in the brains of middle cerebral artery occlusion （MCAO） mice by regulating the expression of neutrophil-related chemokines in exosomes， thereby achieving therapeutic effects. MethodsA total of 130 male specific pathogen-free （SPF） C57BL/6J mice were randomly divided into four groups： Sham-operated group， MCAO model group， Huanglian Jiedutang group （6 g·kg^-1）， and Ginaton group （21.6 mg·kg^-1）， with 10 mice in the Ginaton group and 40 mice in each of the remaining three groups. Mice in the Huanglian Jiedutang group and the Ginaton group were administered the corresponding drugs by oral gavage once daily at a volume of 0.15 mL·（10 g）^-1 for 7 consecutive days， while the sham-operated and model groups received an equal volume of saline via the same route. After 7 days， MCAO surgery was performed. The distal and proximal ends of the right common carotid artery （CCA） were ligated， a small incision was made between the two ligatures， and a silicone rubber-coated monofilament with a rounded tip was inserted into the lumen to occlude the CCA. The filament was left in place for 1 h to establish a focal cerebral ischemia model. At 24 h after modeling， mice were evaluated. Neurological function was assessed using the Longa score. Cerebral infarct volume was measured by 2，3，5-triphenyltetrazolium chloride （TTC） staining. Cerebral blood flow was observed by laser speckle imaging. Hematoxylin and eosin （HE） staining and Nissl staining were used to observe pathological changes in brain tissues. Exosomes were isolated from mouse plasma and brain tissues by ultracentrifugation and molecular size exclusion and identified by electron microscopy， particle size analysis， and protein blotting. Long-chain RNA libraries of exosomes were constructed and sequenced. Real-time quantitative reverse transcription polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of inflammatory factors and neutrophil-related chemokines in exosomes from plasma and brain tissues of each group. Enzyme-linked immunosorbent assay （ELISA） was used to detect the protein expression of inflammatory factors and neutrophil-related chemokines in exosomes from brain tissues of each group. Immunohistochemistry was used to detect the expression of the neutrophil-specific protein myeloperoxidase （MPO） in the brains of mice in each group. ResultsCompared with the sham-operated group， the model group showed decreased neurological function scores （P<0.01）， obvious cerebral infarction （P<0.01）， reduced cerebral blood flow （P<0.01）， neuronal necrosis in the brain， and decreased numbers of Nissl bodies （P<0.01）. The mRNA expression levels of IL-1β， MPO， CXCL1， CXCL2， CXCL3， CXCL10， CCL2， and CCL3 in exosomes from plasma and brain tissues were significantly increased （P<0.05， P<0.01）. The protein expression levels of IL-1β， MPO， CXCL2， and CXCL10 in exosomes from brain tissues were increased （P<0.05， P<0.01）， and MPO-positive rates and mean optical density values in brain tissues were elevated （P<0.01）. Compared with the model group， the Huanglian Jiedutang group and the Ginaton group showed increased neurological function scores （P<0.05）， reduced cerebral infarct volume （P<0.01）， restored cerebral blood flow （P<0.01）， reduced necrotic cells in the brain， and increased numbers of Nissl bodies （P<0.01）. In the Huanglian Jiedutang group， the mRNA expression levels of IL-1β， MPO， CXCL1， CXCL2， CXCL3， CXCL10， CCL2， and CCL3 in exosomes from plasma and brain tissues were decreased （P<0.05， P<0.01）. The protein expression levels of IL-1β， MPO， CXCL2， and CXCL10 in exosomes from brain tissues were reduced （P<0.05， P<0.01）， and MPO-positive rates and mean optical density values in brain tissues were decreased （P<0.01）. ConclusionHuanglian Jiedutang can effectively regulate the expression of neutrophil-related chemokines in exosomes from plasma and brain tissues of MCAO mice， thereby reducing neutrophil infiltration in the brain and achieving therapeutic effects.

ObjectiveTo evaluate the therapeutic effects of Huanglian Jiedutang on cerebral infarction injury in a mouse model of middle cerebral artery occlusion （MCAO） and to explore its mechanism of action on oligodendrocytes， particularly its potential in myelin repair. MethodsMultiple experimental approaches were used to evaluate cerebral ischemic injury and the effects of drug intervention. Laser speckle imaging was used to detect changes in cerebral blood flow， 2，3，5-Triphenyltetrazolium chloride （TTC） staining was used to measure infarct volume， and neurological function was scored according to the Zea-Longa criteria. Brain tissues were routinely embedded in paraffin and subjected to HE and Nissl staining to observe tissue structure and neuronal damage. Animals were divided into a sham group （n=24）， model group （n=24）， Huanglian Jiedutang group （n=24）， and Ginkgo biloba extract （GBE） group （n=18）. After 1 week of acclimatization， intragastric administration was initiated. The sham and model groups received normal saline， the Huanglian Jiedutang group was administered 1.82 g·kg^-1， and the GBE group was administered 0.432 g·kg^-1 after preparation as a 2.16 g·L^-1 solution. All groups were treated for 5 consecutive days at a dose of 0.2 mL·（10 g）^-¹·d^-¹. The MCAO model was established after the final administration on day 6. Single-cell RNA sequencing was used to analyze brain tissue cellular composition and changes in oligodendrocyte subpopulations. Distinct subpopulations were identified by Uniform manifold approximation and projection （UMAP） dimensionality reduction and unsupervised clustering， and marker gene expression was analyzed. Pathway enrichment and causal inference were further performed using IPA. Finally， real-time quantitative PCR was used to verify mRNA expression changes of myelin-related genes. ResultsCompared with the sham group， the model group showed significantly increased neurological function scores （P<0.01）， significantly impaired blood flow （P<0.01）， significantly enlarged cerebral infarct area （P<0.01）， and pathological changes including disordered cortical structural arrangement， aggravated cytoplasmic vacuolization， and increased Nissl bodies. Compared with the model group， the Huanglian Jiedutang and GBE groups showed significantly decreased neurological function scores （P<0.01）， markedly restored blood flow levels （P<0.01）， significantly reduced cerebral infarct area （P<0.01）， and improvement in cortical structural disorder， alleviation of cytoplasmic vacuolization， and a reduction in Nissl bodies. Single-cell data showed that a myelin-associated oligodendrocyte （Mye-OL） subpopulation existed among oligodendrocytes， which was closely related to myelin generation. Compared with the sham group， the number of Mye-OL cells decreased in the model group. Compared with the model group， the number of Mye-OL cells increased in the Huanglian Jiedutang group. This subpopulation promoted the expression of myelin-related genes， including MOG， MBP， and MAG， via transcription factors such as OLIG1， OLIG2， NKX2-2， and SOX10， thereby regulating myelin generation， restoring cognition， and exerting therapeutic effects on acute cerebral infarction. Compared with the sham group， the mRNA expression levels of OLIG1， OLIG2， NKX2-2， and SOX10 were significantly downregulated in the model group （P<0.01）， and the mRNA expression levels of myelin-related genes， including MOG， MBP， and MAG， were also significantly downregulated （P<0.01）. In contrast， compared with the model group， the Huanglian Jiedutang and GBE groups showed significantly upregulated mRNA expression levels of OLIG1， OLIG2， NKX2-2， and SOX10 （P<0.01）， and significantly upregulated mRNA expression levels of myelin-related genes， including MOG， MBP， and MAG （P<0.01）. ConclusionHuanglian Jiedutang exerts therapeutic effects on acute cerebral infarction by regulating the OLIG1/2-NKX2-2-SOX10 signaling pathway to promote myelin generation by Mye-OL cells.

ObjectiveTo investigate the characteristics of metabolic reprogramming during cerebral ischemia-reperfusion injury using single-cell transcriptome sequencing， analyze the heterogeneity of microglial populations， and evaluate the interventional effects of Huanglian Jiedutang on metabolic abnormalities and neuroinflammation. MethodsA transient middle cerebral artery occlusion （tMCAO） model was used to establish ischemic stroke in mice. Local cerebral blood flow changes were monitored by laser speckle imaging. Neurological impairment was evaluated using the Zea-Longa score， and histopathological damage in brain tissue was observed by HE and Nissl staining. Animals were divided into a sham group， model group， Huanglian Jiedutang group， and Ginkgo biloba extract （GBE） group. After 1 week of acclimatization， intragastric administration was initiated. The sham and model groups received normal saline， the Huanglian Jiedutang group was administered 1.82 g·kg^-1， and the GBE group was administered 0.432 g·kg^-1 after preparation as a 2.16 mg/mL solution. All groups were treated for 5 consecutive days （0.2 mL/10 g/day）， and the tMCAO model was established on day 6 after the final administration. At the molecular level， single-cell RNA sequencing was performed on ischemic hemisphere tissue. Non-negative matrix factorization （NMF） was used to cluster microglial subpopulations， combined with differential expression analysis， metabolic reprogramming assessment， and inflammatory factor correlation analysis to elucidate their functional characteristics in ischemia-reperfusion injury. Transcription factor enrichment analysis was further conducted to identify key regulatory nodes. Finally， PCR was used to detect mRNA expression changes of relevant genes to validate the single-cell sequencing results. ResultsCompared with the sham group， the model group showed increased neurological function scores （P<0.01）， decreased blood flow levels （P<0.01）， disordered cortical structure， increased cytoplasmic vacuolization， and increased Nissl bodies. Compared with the model group， the Huanglian Jiedutang and GBE groups showed decreased neurological function scores （P<0.01）， increased blood flow levels （P<0.01）， alleviated cortical structural disorder， reduced cytoplasmic vacuolization， and decreased Nissl bodies. Single-cell analysis showed that microglia could be divided into five subpopulations. Among them， clusters 3 and 5 exhibited significant pro-inflammatory phenotypes， with marked activation of hypoxia and NF-κB signaling pathways， and were identified as pro-inflammatory subpopulations. Clusters 1 and 2 were enriched in Wnt/β-catenin and transforming growth factor（TGF）-β signaling pathways and exhibited prominent anti-inflammatory and reparative characteristics. Meanwhile， glycolysis-related genes， such as HK2， PFKP， and LDHA， were significantly upregulated in the pro-inflammatory subpopulations. Correlation analysis showed that the expression levels of inflammatory molecules were positively correlated with glycolysis-related gene expression levels， whereas the expression levels of reparative and anti-inflammatory molecules were negatively correlated with glycolysis-related gene expression levels， indicating that microglia rely on the glycolytic pathway for energy acquisition under ischemic conditions. Further single-cell transcriptome analysis revealed that Huanglian Jiedutang effectively downregulated key genes driving metabolic reprogramming （such as HK2， PFKP， and LDHA）， significantly reduced the proportion of microglial subpopulations accompanied by glycolytic reprogramming， and inhibited their transformation toward a damage phenotype， thereby reducing inflammatory injury. Meanwhile， compared with the sham group， the mRNA expression levels of interleukin （IL）-1β， IL-6， tumor necrosis factor（TNF）-α， CCL2， CXCL2， and CSF3 were significantly upregulated （P<0.01） in the model group， whereas the mRNA expression levels of endothelial- and pericyte-related functional genes， including RGS5， PECAM1， VEGFB， and NOS3， were significantly downregulated （P<0.01）. In contrast， compared with the model group， the Huanglian Jiedutang and GBE groups showed significantly decreased mRNA expression levels of IL-1β， IL-6， TNF-α， CCL2， CXCL2， and CSF3 （P<0.01）， and significantly increased mRNA expression levels of endothelial- and pericyte-related functional genes， including RGS5， PECAM1， VEGFB， and NOS3 （P<0.01）. ConclusionHuanglian Jiedutang exerts neuroprotective effects by regulating the metabolic reprogramming state of microglia and modulating their inflammatory levels， thereby inhibiting neuroinflammatory injury.

LIU Wansu， as the foremost of the four great masters of the Jin-Yuan period， established the "theory of fire-heat'' and extended the fire-heat pathogenesis framework to the field of stroke， thereby forming the theory of ''fire-heat inducing stroke''. This achieved a paradigmatic shift in stroke etiology from ''exogenous wind inducing stroke'' to ''fire-heat inducing stroke''. This paper systematically reviews the developmental trajectory of LIU Wansu's ''fire-heat inducing stroke'' theory and explores the social background， academic origins， and core connotations of its theoretical construction. The study found that， based on the ''Nineteen Pathomechanisms'' in the Huangdi's Internal Classic （Huang Di Nei Jing） and combined with clinical practice， LIU Wansu proposed that fire-heat is the fundamental cause of stroke， and that the Six Climatic Factors and the Five Zhi-Emotions can all transform into fire. He further constructed a stratified syndrome differentiation and therapeutic system centered on clearing heat and purging fire， emphasizing differentiated treatment of exterior and interior syndromes， Six Meridians syndrome differentiation， and seasonally adjusted medication. This theory not only resolved the diagnostic and therapeutic dilemmas of febrile epidemic diseases during the Jin-Yuan period， but also exerted a profound influence on later physicians such as ZHANG Zihe and ZHU Danxi， thereby promoting the pluralistic development of stroke theory in traditional Chinese medicine （TCM）. Modern pharmacological research provides solid scientific evidence， confirming that the ''fire-heat'' pathological state is highly associated with key mechanisms such as excessive inflammatory responses， oxidative stress， and excitatory amino acid toxicity following cerebral ischemia. Heat-clearing and fire-purging prescriptions and agents， such as Huanglian Jiedu Tang and baicalin， can exert multi-target neuroprotective effects by regulating inflammatory signaling， enhancing antioxidant enzyme activity， and balancing neurotransmitters. This not only verifies the scientific basis of the ''fire-heat inducing stroke'' theory from a modern biological perspective but also provides conclusive evidence for the clinical application of heat-clearing and fire-purging therapy. LIU Wansu's ''fire-heat inducing stroke'' theory represents a major milestone in the historical understanding of stroke pathogenesis， and its academically transitional insights continue to hold core guiding value for the pattern identification and treatment of ischemic stroke today.

ObjectiveTo investigate whether Huanglian Jiedutang can inhibit neutrophil infiltration in the brains of middle cerebral artery occlusion （MCAO） mice by regulating the expression of neutrophil-related chemokines in exosomes， thereby achieving therapeutic effects. MethodsA total of 130 male specific pathogen-free （SPF） C57BL/6J mice were randomly divided into four groups： Sham-operated group， MCAO model group， Huanglian Jiedutang group （6 g·kg^-1）， and Ginaton group （21.6 mg·kg^-1）， with 10 mice in the Ginaton group and 40 mice in each of the remaining three groups. Mice in the Huanglian Jiedutang group and the Ginaton group were administered the corresponding drugs by oral gavage once daily at a volume of 0.15 mL·（10 g）^-1 for 7 consecutive days， while the sham-operated and model groups received an equal volume of saline via the same route. After 7 days， MCAO surgery was performed. The distal and proximal ends of the right common carotid artery （CCA） were ligated， a small incision was made between the two ligatures， and a silicone rubber-coated monofilament with a rounded tip was inserted into the lumen to occlude the CCA. The filament was left in place for 1 h to establish a focal cerebral ischemia model. At 24 h after modeling， mice were evaluated. Neurological function was assessed using the Longa score. Cerebral infarct volume was measured by 2，3，5-triphenyltetrazolium chloride （TTC） staining. Cerebral blood flow was observed by laser speckle imaging. Hematoxylin and eosin （HE） staining and Nissl staining were used to observe pathological changes in brain tissues. Exosomes were isolated from mouse plasma and brain tissues by ultracentrifugation and molecular size exclusion and identified by electron microscopy， particle size analysis， and protein blotting. Long-chain RNA libraries of exosomes were constructed and sequenced. Real-time quantitative reverse transcription polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of inflammatory factors and neutrophil-related chemokines in exosomes from plasma and brain tissues of each group. Enzyme-linked immunosorbent assay （ELISA） was used to detect the protein expression of inflammatory factors and neutrophil-related chemokines in exosomes from brain tissues of each group. Immunohistochemistry was used to detect the expression of the neutrophil-specific protein myeloperoxidase （MPO） in the brains of mice in each group. ResultsCompared with the sham-operated group， the model group showed decreased neurological function scores （P<0.01）， obvious cerebral infarction （P<0.01）， reduced cerebral blood flow （P<0.01）， neuronal necrosis in the brain， and decreased numbers of Nissl bodies （P<0.01）. The mRNA expression levels of IL-1β， MPO， CXCL1， CXCL2， CXCL3， CXCL10， CCL2， and CCL3 in exosomes from plasma and brain tissues were significantly increased （P<0.05， P<0.01）. The protein expression levels of IL-1β， MPO， CXCL2， and CXCL10 in exosomes from brain tissues were increased （P<0.05， P<0.01）， and MPO-positive rates and mean optical density values in brain tissues were elevated （P<0.01）. Compared with the model group， the Huanglian Jiedutang group and the Ginaton group showed increased neurological function scores （P<0.05）， reduced cerebral infarct volume （P<0.01）， restored cerebral blood flow （P<0.01）， reduced necrotic cells in the brain， and increased numbers of Nissl bodies （P<0.01）. In the Huanglian Jiedutang group， the mRNA expression levels of IL-1β， MPO， CXCL1， CXCL2， CXCL3， CXCL10， CCL2， and CCL3 in exosomes from plasma and brain tissues were decreased （P<0.05， P<0.01）. The protein expression levels of IL-1β， MPO， CXCL2， and CXCL10 in exosomes from brain tissues were reduced （P<0.05， P<0.01）， and MPO-positive rates and mean optical density values in brain tissues were decreased （P<0.01）. ConclusionHuanglian Jiedutang can effectively regulate the expression of neutrophil-related chemokines in exosomes from plasma and brain tissues of MCAO mice， thereby reducing neutrophil infiltration in the brain and achieving therapeutic effects.

ObjectiveTo evaluate the therapeutic effects of Huanglian Jiedutang on cerebral infarction injury in a mouse model of middle cerebral artery occlusion （MCAO） and to explore its mechanism of action on oligodendrocytes， particularly its potential in myelin repair. MethodsMultiple experimental approaches were used to evaluate cerebral ischemic injury and the effects of drug intervention. Laser speckle imaging was used to detect changes in cerebral blood flow， 2，3，5-Triphenyltetrazolium chloride （TTC） staining was used to measure infarct volume， and neurological function was scored according to the Zea-Longa criteria. Brain tissues were routinely embedded in paraffin and subjected to HE and Nissl staining to observe tissue structure and neuronal damage. Animals were divided into a sham group （n=24）， model group （n=24）， Huanglian Jiedutang group （n=24）， and Ginkgo biloba extract （GBE） group （n=18）. After 1 week of acclimatization， intragastric administration was initiated. The sham and model groups received normal saline， the Huanglian Jiedutang group was administered 1.82 g·kg^-1， and the GBE group was administered 0.432 g·kg^-1 after preparation as a 2.16 g·L^-1 solution. All groups were treated for 5 consecutive days at a dose of 0.2 mL·（10 g）^-¹·d^-¹. The MCAO model was established after the final administration on day 6. Single-cell RNA sequencing was used to analyze brain tissue cellular composition and changes in oligodendrocyte subpopulations. Distinct subpopulations were identified by Uniform manifold approximation and projection （UMAP） dimensionality reduction and unsupervised clustering， and marker gene expression was analyzed. Pathway enrichment and causal inference were further performed using IPA. Finally， real-time quantitative PCR was used to verify mRNA expression changes of myelin-related genes. ResultsCompared with the sham group， the model group showed significantly increased neurological function scores （P<0.01）， significantly impaired blood flow （P<0.01）， significantly enlarged cerebral infarct area （P<0.01）， and pathological changes including disordered cortical structural arrangement， aggravated cytoplasmic vacuolization， and increased Nissl bodies. Compared with the model group， the Huanglian Jiedutang and GBE groups showed significantly decreased neurological function scores （P<0.01）， markedly restored blood flow levels （P<0.01）， significantly reduced cerebral infarct area （P<0.01）， and improvement in cortical structural disorder， alleviation of cytoplasmic vacuolization， and a reduction in Nissl bodies. Single-cell data showed that a myelin-associated oligodendrocyte （Mye-OL） subpopulation existed among oligodendrocytes， which was closely related to myelin generation. Compared with the sham group， the number of Mye-OL cells decreased in the model group. Compared with the model group， the number of Mye-OL cells increased in the Huanglian Jiedutang group. This subpopulation promoted the expression of myelin-related genes， including MOG， MBP， and MAG， via transcription factors such as OLIG1， OLIG2， NKX2-2， and SOX10， thereby regulating myelin generation， restoring cognition， and exerting therapeutic effects on acute cerebral infarction. Compared with the sham group， the mRNA expression levels of OLIG1， OLIG2， NKX2-2， and SOX10 were significantly downregulated in the model group （P<0.01）， and the mRNA expression levels of myelin-related genes， including MOG， MBP， and MAG， were also significantly downregulated （P<0.01）. In contrast， compared with the model group， the Huanglian Jiedutang and GBE groups showed significantly upregulated mRNA expression levels of OLIG1， OLIG2， NKX2-2， and SOX10 （P<0.01）， and significantly upregulated mRNA expression levels of myelin-related genes， including MOG， MBP， and MAG （P<0.01）. ConclusionHuanglian Jiedutang exerts therapeutic effects on acute cerebral infarction by regulating the OLIG1/2-NKX2-2-SOX10 signaling pathway to promote myelin generation by Mye-OL cells.

ObjectiveTo investigate the characteristics of metabolic reprogramming during cerebral ischemia-reperfusion injury using single-cell transcriptome sequencing， analyze the heterogeneity of microglial populations， and evaluate the interventional effects of Huanglian Jiedutang on metabolic abnormalities and neuroinflammation. MethodsA transient middle cerebral artery occlusion （tMCAO） model was used to establish ischemic stroke in mice. Local cerebral blood flow changes were monitored by laser speckle imaging. Neurological impairment was evaluated using the Zea-Longa score， and histopathological damage in brain tissue was observed by HE and Nissl staining. Animals were divided into a sham group， model group， Huanglian Jiedutang group， and Ginkgo biloba extract （GBE） group. After 1 week of acclimatization， intragastric administration was initiated. The sham and model groups received normal saline， the Huanglian Jiedutang group was administered 1.82 g·kg^-1， and the GBE group was administered 0.432 g·kg^-1 after preparation as a 2.16 mg/mL solution. All groups were treated for 5 consecutive days （0.2 mL/10 g/day）， and the tMCAO model was established on day 6 after the final administration. At the molecular level， single-cell RNA sequencing was performed on ischemic hemisphere tissue. Non-negative matrix factorization （NMF） was used to cluster microglial subpopulations， combined with differential expression analysis， metabolic reprogramming assessment， and inflammatory factor correlation analysis to elucidate their functional characteristics in ischemia-reperfusion injury. Transcription factor enrichment analysis was further conducted to identify key regulatory nodes. Finally， PCR was used to detect mRNA expression changes of relevant genes to validate the single-cell sequencing results. ResultsCompared with the sham group， the model group showed increased neurological function scores （P<0.01）， decreased blood flow levels （P<0.01）， disordered cortical structure， increased cytoplasmic vacuolization， and increased Nissl bodies. Compared with the model group， the Huanglian Jiedutang and GBE groups showed decreased neurological function scores （P<0.01）， increased blood flow levels （P<0.01）， alleviated cortical structural disorder， reduced cytoplasmic vacuolization， and decreased Nissl bodies. Single-cell analysis showed that microglia could be divided into five subpopulations. Among them， clusters 3 and 5 exhibited significant pro-inflammatory phenotypes， with marked activation of hypoxia and NF-κB signaling pathways， and were identified as pro-inflammatory subpopulations. Clusters 1 and 2 were enriched in Wnt/β-catenin and transforming growth factor（TGF）-β signaling pathways and exhibited prominent anti-inflammatory and reparative characteristics. Meanwhile， glycolysis-related genes， such as HK2， PFKP， and LDHA， were significantly upregulated in the pro-inflammatory subpopulations. Correlation analysis showed that the expression levels of inflammatory molecules were positively correlated with glycolysis-related gene expression levels， whereas the expression levels of reparative and anti-inflammatory molecules were negatively correlated with glycolysis-related gene expression levels， indicating that microglia rely on the glycolytic pathway for energy acquisition under ischemic conditions. Further single-cell transcriptome analysis revealed that Huanglian Jiedutang effectively downregulated key genes driving metabolic reprogramming （such as HK2， PFKP， and LDHA）， significantly reduced the proportion of microglial subpopulations accompanied by glycolytic reprogramming， and inhibited their transformation toward a damage phenotype， thereby reducing inflammatory injury. Meanwhile， compared with the sham group， the mRNA expression levels of interleukin （IL）-1β， IL-6， tumor necrosis factor（TNF）-α， CCL2， CXCL2， and CSF3 were significantly upregulated （P<0.01） in the model group， whereas the mRNA expression levels of endothelial- and pericyte-related functional genes， including RGS5， PECAM1， VEGFB， and NOS3， were significantly downregulated （P<0.01）. In contrast， compared with the model group， the Huanglian Jiedutang and GBE groups showed significantly decreased mRNA expression levels of IL-1β， IL-6， TNF-α， CCL2， CXCL2， and CSF3 （P<0.01）， and significantly increased mRNA expression levels of endothelial- and pericyte-related functional genes， including RGS5， PECAM1， VEGFB， and NOS3 （P<0.01）. ConclusionHuanglian Jiedutang exerts neuroprotective effects by regulating the metabolic reprogramming state of microglia and modulating their inflammatory levels， thereby inhibiting neuroinflammatory injury.

ObjectiveTo investigate whether Huanglian Jiedutang （HLJD） and its major active constituents （geniposide， baicalin， and berberine） can inhibit the inflammatory response of BV2 cells under lipopolysaccharide （LPS） stimulation via the high-mobility group protein B1 （HMGB1）/Toll-like receptor 4 （TLR4）/nuclear factor-κB （NF-κB） signaling pathway， and to explore differences in therapeutic efficacy among the three monomers， their combined formula， and HLJD under equal content ratios. MethodsBV2 microglial cells were used as the primary experimental model. Cell viability was assessed using the cell counting kit-8 （CCK-8） method to examine the effects of different concentrations of dimethyl sulfoxide （DMSO， 0.8%， 0.4%， 0.2%， 0.1%， and 0.05%） on cell viability. IncuCyte was employed to monitor the growth of cells under different concentrations of HLJD （200， 100， 50， 25， 12.5， 6.25 mg·L^-1）. Nitric oxide （NO） assay was used to screen the optimal HLJD concentration. High-performance liquid chromatography （HPLC） determined the content of geniposide， baicalin， and berberine in HLJD， and experimental groups were subsequently established according to the relative proportions of these constituents. CCK-8 assay evaluated cell viability under different treatments. Enzyme-linked immunosorbent assay （ELISA） measured levels of inflammatory factors （TNF-α， IL-1β， IL-6， IL-10） in the supernatant. Flow cytometry assessed the effects of treatments on M1-type polarization of BV2 cells. Western blot determined the expression levels of HMGB1， TLR4， and NF-κB-related proteins. ResultsCompared with the blank group， DMSO at concentrations ≤0.2% did not affect cell viability within 48 h. BV2 cell growth plateaued at 24 h after treatment with 200 mg·L^-1 HLJD. Under stimulation with 2 mg·L^-1 LPS， this concentration of HLJD effectively reduced NO release， and 6 h pre-treatment had a stronger inhibitory effect on NO than direct administration. HPLC results showed that 1 mg of HLJD freeze-dried powder contained approximately 24 μg of geniposide， 15 μg of baicalin， and 30 μg of berberine. Based on these ratios， experimental groups were blank， LPS （2 mg·L^-1）， HLJD （200 mg·L^-1）， monomer combination， geniposide （4.8 mg·L^-1）， baicalin （3 mg·L^-1）， and berberine （6 mg·L^-1）. The monomer combination group consisted of all three active constituents dissolved together. LPS and HLJD or its active constituents did not affect cell viability compared with the blank group. LPS significantly increased TNF-α， IL-1β， IL-6， and IL-10 in the supernatant （P<0.01）. HLJD and its active constituents significantly reduced pro-inflammatory factors TNF-α， IL-1β， and IL-6 （P<0.05， P<0.01） while upregulating anti-inflammatory IL-10 （P<0.01）， with the monomer combination showing the strongest effect （P<0.05， P<0.01）. Compared with the blank group， LPS significantly increased the proportion of CD80⁺CD86⁺ （M1-type） BV2 cells （P<0.01）. HLJD and its constituents partially inhibited M1 polarization （P<0.05， P<0.01）， with the monomer combination exhibiting the most pronounced effect （P<0.05， P<0.01）. Compared with the blank group， LPS upregulated HMGB1， TLR4， and NF-κB-related proteins （P<0.01）， whereas HLJD and its active constituents significantly reduced their expression （P<0.05， P<0.01）， with the monomer combination having the strongest regulatory effect （P<0.05， P<0.01）. ConclusionHLJD and its major active constituents （geniposide， baicalin， berberine） can inhibit LPS-induced inflammatory responses in BV2 cells. The combination of the three active constituents demonstrates the most potent anti-inflammatory effect， significantly attenuating M1-type polarization of BV2 cells via the HMGB1/TLR4/NF-κB signaling pathway.

ObjectiveTo investigate the regulatory effects of Huanglian Jiedutang （HLJDT） on immune cell migration， blood-brain barrier protection， and cellular functional recovery in a model of ischemic stroke. MethodsA transient middle cerebral artery occlusion （tMCAO） model was established in mice to induce ischemic stroke. Cerebral blood flow and neurological function were evaluated using laser speckle imaging and neurological deficit scoring. Histopathological damage in brain tissues was assessed by hematoxylin-eosin （HE） and Nissl staining. Mice were divided into a sham group， a model group， an HLJDT group， and a Ginkgo biloba extract （GBE） group. After one week of acclimatization， intragastric administration was initiated. The sham and model groups received normal saline， the HLJDT group received HLJDT at 1.82 g·kg^-¹， and the GBE group received GBE at 0.432 g·kg^-¹. Administration was continued for 5 consecutive days， and the tMCAO model was established after the final dose on day 6. Single-cell RNA sequencing was performed on brain tissues and peripheral immune cells. UMAP and odds ratio （OR） indices were used to analyze cell distribution. Differential expression analysis was conducted to evaluate the effects of HLJDT on endothelial cells， pericytes， and macrophages， combined with CellChat and decoupler to analyze cell-cell communication and transcription factor regulation. Finally， PCR and ELISA were used to validate the mRNA and protein expression of relevant genes. ResultsCompared with the sham group， the model group showed significantly increased neurological deficit scores （P<0.01） and significantly decreased cerebral blood flow （P<0.01）， accompanied by cortical structural disorder， aggravated cytoplasmic vacuolization， and increased numbers of Nissl bodies. Compared with the model group， both the HLJDT and GBE groups exhibited significantly reduced neurological deficit scores （P<0.01） and markedly improved cerebral blood flow （P<0.01）， along with amelioration of cortical structural disorder， alleviated cytoplasmic vacuolization， and reduced numbers of Nissl bodies. Single-cell analysis showed that HLJDT protected endothelial cells and pericytes by preventing their reduction， restored the expression of functional genes in these cells （e.g.， PECAM1 and NOS3）， and downregulated the expression of chemokines and adhesion-related factors （e.g.， CCL2 and CXCL2）. In macrophages， HLJDT reduced their recruitment to the central nervous system and downregulated the expression of chemokine receptors and inflammatory factors （e.g.， IL-6， CCR2， and CXCR2）. Cell-cell communication analysis further indicated that HLJDT， through the above mechanisms， alleviated damage to pericytes and endothelial cells， reduced their recruitment of macrophages， and decreased ligand-receptor interactions in chemokine signaling pathways （including CCL， CXCL， and CSF3） between pericytes/endothelial cells and macrophages， thereby preventing secondary injury. Compared with the sham group， the model group showed significantly upregulated mRNA expression levels of IL-1β， IL-6， TNF-α， CCL2， CXCL2， and CSF3 （P<0.01）， while mRNA expression levels of endothelial- and pericyte function-related genes （RGS5， PECAM1， VEGFB， and NOS3） were significantly downregulated （P<0.01）. In contrast， compared with the model group， the HLJDT and GBE groups exhibited significantly decreased mRNA expression levels of IL-1β， IL-6， TNF-α， CCL2， CXCL2， and CSF3 （P<0.01）， and significantly increased expression of RGS5， PECAM1， VEGFB， and NOS3 （P<0.01）. At the protein level， compared with the sham group， the model group showed significantly increased expression of IL-1β， IL-6， and TNF-α （P<0.01）， whereas these protein levels were significantly reduced in the HLJDT and GBE groups compared with the model group （P<0.01）. ConclusionHLJDT reduces neuronal damage in ischemic stroke by protecting endothelial cells and pericytes， while inhibiting their interaction with macrophages， thereby mitigating secondary injury in the central nervous system.