ObjectiveThis paper aims to find the identified and validated clinical biomarker data building upon a clinical study of early-phase phase Ⅱ and investigate the correlation analysis of Huanglian Jiedu Wan on syndrome improvement and clinical biomarkers in the treatment of "excess heat-toxicity" based on a machine learning model. Additionally， the effective prediction of clinical biomarker values for the main symptoms of the "excess heat-toxicity" syndrome was assessed. MethodsA total of 229 patients meeting the inclusion criteria for "excess heat-toxicity" syndrome were randomly divided into the Huanglian Jiedu Wan group and the placebo group. Syndrome score transition matrices were constructed for the Huanglian Jiedu Wan group and the placebo group based on three main symptoms of "excess heat-toxicity" syndrome， such as oral ulcers， sore throat， and gum swelling and pain. Data from the patients with these three syndromes were also integrated for an overall analysis. The corresponding syndrome score transition matrices were further constructed to visualize symptom change trends of the patients in the two groups via heatmaps. Based on the identified and validated clinical biomarkers related to inflammation， oxidative stress， and energy metabolism in the early phase， Spearman correlation analysis was employed to analyze and evaluate the associations between clinical biomarkers and syndrome improvement. Key clinical biomarkers reflecting the effect of Huanglian Jiedu Wan were screened through the comparison of differences between groups. An extreme gradient boosting （XGBoost） algorithm was used to develop a prediction model for main symptom classification， with classification performance evaluated through 10-fold cross-validation. Feature importance analysis was applied to identify variables with the greatest contribution to the prediction result. ResultsThe syndrome transition matrix results indicated that the Huanglian Jiedu Wan group showed a superior effect to the placebo group in improving oral ulcers， sore throat， and overall symptoms， with significant effects observed especially in sore throat and overall symptom analyses （P<0.01）. Spearman correlation analysis revealed that several clinical biomarkers positively correlated with "excess heat-toxicity" syndrome and its main symptom improvement， were also called "heat-related biomarkers"， including succinic acid， α-ketoglutaric acid， glycine， lactic acid， adenosine monophosphate （AMP）， tumor necrosis factor-α （TNF-α）， interferon-γ （IFN-γ）， interleukin-1β （IL-1β）， interleukin-4 （IL-4）， interleukin-6 （IL-6）， interleukin-8 （IL-8）， interleukin-10 （IL-10）， and so on. Conversely， clinical biomarkers negatively correlated with symptom severity， were also called "heat-clearing related biomarkers" after administration of Huanglian Jiedu Wan， including malic acid， fumaric acid， cis-aconitic acid， adrenocorticotropic hormone （ACTH）， IL-1β， IL-4， IL-8， succinic acid， and citric acid. The XGBoost classification model using all 52 biomarkers as variables achieved an average test accuracy of 0.754 and an average F1 score of 0.777. Feature importance analysis identified the scores of glutamic acid in saliva and IL-6 were the highest in all the variables， with importance scores of 0.081 and 0.080， respectively. After screening out 14 key variables and optimizing the parameters， model performance improved to an average accuracy of 0.758 and an F1 score of 0.798. Feature importance analysis further determined that the glutamic acid in saliva and IL-6 showed obvious changes after screening the variables， confirming the good syndrome prediction ability of the model constructed by these key clinical biomarkers. ConclusionThis study systematically elucidates the correlation between syndrome improvement and clinical biomarkers of Huanglian Jiedu Wan in the treatment of "excess heat-toxicity" syndrome. An XGBoost classification model based on key clinical biomarkers is successfully established， achieving effective prediction of the symptoms related to the "excess heat-toxicity" syndrome such as oral ulcers and sore throat and providing a new insight for objective identification of traditional Chinese medicine syndromes.

ObjectiveThis paper aims to find the identified and validated clinical biomarker data building upon a clinical study of early-phase phase Ⅱ and investigate the correlation analysis of Huanglian Jiedu Wan on syndrome improvement and clinical biomarkers in the treatment of "excess heat-toxicity" based on a machine learning model. Additionally， the effective prediction of clinical biomarker values for the main symptoms of the "excess heat-toxicity" syndrome was assessed. MethodsA total of 229 patients meeting the inclusion criteria for "excess heat-toxicity" syndrome were randomly divided into the Huanglian Jiedu Wan group and the placebo group. Syndrome score transition matrices were constructed for the Huanglian Jiedu Wan group and the placebo group based on three main symptoms of "excess heat-toxicity" syndrome， such as oral ulcers， sore throat， and gum swelling and pain. Data from the patients with these three syndromes were also integrated for an overall analysis. The corresponding syndrome score transition matrices were further constructed to visualize symptom change trends of the patients in the two groups via heatmaps. Based on the identified and validated clinical biomarkers related to inflammation， oxidative stress， and energy metabolism in the early phase， Spearman correlation analysis was employed to analyze and evaluate the associations between clinical biomarkers and syndrome improvement. Key clinical biomarkers reflecting the effect of Huanglian Jiedu Wan were screened through the comparison of differences between groups. An extreme gradient boosting （XGBoost） algorithm was used to develop a prediction model for main symptom classification， with classification performance evaluated through 10-fold cross-validation. Feature importance analysis was applied to identify variables with the greatest contribution to the prediction result. ResultsThe syndrome transition matrix results indicated that the Huanglian Jiedu Wan group showed a superior effect to the placebo group in improving oral ulcers， sore throat， and overall symptoms， with significant effects observed especially in sore throat and overall symptom analyses （P<0.01）. Spearman correlation analysis revealed that several clinical biomarkers positively correlated with "excess heat-toxicity" syndrome and its main symptom improvement， were also called "heat-related biomarkers"， including succinic acid， α-ketoglutaric acid， glycine， lactic acid， adenosine monophosphate （AMP）， tumor necrosis factor-α （TNF-α）， interferon-γ （IFN-γ）， interleukin-1β （IL-1β）， interleukin-4 （IL-4）， interleukin-6 （IL-6）， interleukin-8 （IL-8）， interleukin-10 （IL-10）， and so on. Conversely， clinical biomarkers negatively correlated with symptom severity， were also called "heat-clearing related biomarkers" after administration of Huanglian Jiedu Wan， including malic acid， fumaric acid， cis-aconitic acid， adrenocorticotropic hormone （ACTH）， IL-1β， IL-4， IL-8， succinic acid， and citric acid. The XGBoost classification model using all 52 biomarkers as variables achieved an average test accuracy of 0.754 and an average F1 score of 0.777. Feature importance analysis identified the scores of glutamic acid in saliva and IL-6 were the highest in all the variables， with importance scores of 0.081 and 0.080， respectively. After screening out 14 key variables and optimizing the parameters， model performance improved to an average accuracy of 0.758 and an F1 score of 0.798. Feature importance analysis further determined that the glutamic acid in saliva and IL-6 showed obvious changes after screening the variables， confirming the good syndrome prediction ability of the model constructed by these key clinical biomarkers. ConclusionThis study systematically elucidates the correlation between syndrome improvement and clinical biomarkers of Huanglian Jiedu Wan in the treatment of "excess heat-toxicity" syndrome. An XGBoost classification model based on key clinical biomarkers is successfully established， achieving effective prediction of the symptoms related to the "excess heat-toxicity" syndrome such as oral ulcers and sore throat and providing a new insight for objective identification of traditional Chinese medicine syndromes.

Background Prenatal exposure to fine particulate matter (PM_2.5) is closely associated with cortical damage and neuroinflammation in offspring. The cyclic guanosine monophosphate–adenosine monophosphate synthase (cGAS)–stimulator of interferon genes (STING) signaling pathway is a key regulator of inflammation and may be subject to epigenetic regulation. Objective To investigate the role of cGAS-STING pathway activation in PM_2.5-induced cortical damage in offspring mice during pregnancy and the underlying epigenetic regulatory mechanisms. Methods Open field tests were used to assess depressive-like behavior in offspring mice. Morphological analysis was conducted to evaluate cortical damage and microglial activation in offspring brains. Real-time fluorescent quantitative PCR (RT-qPCR) and Western blot (WB) were performed to detect changes in the expression of key molecules in the cGAS-STING pathway in cortical tissue. A PM_2.5-induced microglial cell injury model was established in BV2 cells. Microglial activation was observed, cell viability was measured using the Cell Counting Kit-8 (CCK-8), and the expression levels of inducible nitric oxide synthase (iNOS) and key molecules in the cGAS-STING pathway were detected by RT-qPCR and WB. Bioinformatics analysis was performed to explore the epigenetic regulatory association between the STING signaling pathway and lysine-specific demethylase 5A (KDM5A). Changes in KDM5A mRNA and protein expression, as well as the protein level of histone H3 lysine 4 trimethylation (H3K4me3), were detected in an in vitro PM_2.5 injury model. Using small interfering RNA (siRNA) technology, the KDM5A gene was silenced in BV2 cells exposed to PM_2.5. The protein expression of H3K4me3 was detected to evaluate improvements in microglial activation, changes in inflammatory markers such as iNOS and mannose receptor (CD206), and alterations in the cGAS-STING pathway. Results Compared with the control group, the total distance of offspring mice in the PM_2.5 group was significantly reduced, and both the distance traveled and the time spent in the central area of the open field were significantly decreased (P<0.01, P<0.001), indicating depressive-like behavior in the offspring mice. Compared with the control group, the offspring mice in the PM_2.5 group exhibited disorganized cortical structure and significantly activated microglia (P<0.01), with significantly increased mRNA and protein levels of cGAS and STING (P<0.05, P<0.01, or P<0.001). The in vitro experiments demonstrated that the PM_2.5 treatment induced BV2 cells to polarize toward the M1 phenotype, exhibiting a distinct amoeboid morphology, with upregulated expression of the pro-inflammatory factor iNOS (P<0.05, P<0.01, or P<0.001) and activation of the cGAS-STING pathway (P<0.05, P<0.01). The analysis of RNA-seq data from KDM5A knockout cells revealed significantly downregulated STING expression, suggesting that KDM5A may activate the STING signaling pathway. The in vitro experiments further confirmed that the PM_2.5-treated BV2 cells exhibited significantly elevated mRNA and protein levels of KDM5A (P<0.01), while the H3K4me3 protein levels were markedly reduced (P<0.05). After silencing KDM5A in BV2 cells exposed to PM_2.5, compared with the PM_2.5+siNC group, the PM_2.5+siKDM5A group showed no obvious microglial activation and polarized toward the M2 phenotype, with significantly decreased expression levels of iNOS, cluster of differentiation 16 (CD16), and interleukin-1β (P<0.05, P<0.01), and significantly increased expression levels of anti-inflammatory factors CD206, YM1, and interleukin-10 (P<0.01, P<0.001). Meanwhile, the expression levels of cGAS and STING were also reduced (P<0.05, P<0.01). Conclusion KDM5A activates microglia through the cGAS-STING pathway, thereby contributing to PM_2.5-induced cortical damage in offspring mice during pregnancy.

Background Existing studies have confirmed that fine particulate matter (PM_2.5)is one of the important factors inducing pulmonary fibrosis. Pulmonary fibrosis is the terminal stage of a major category of lung diseases characterized by the destruction of tissue structure, and eventually leading lung ventilation and ventilation dysfunction. No effective pulmonary fibrosis treatment is available yet. Objective To investigate the protective effect of salidroside on pulmonary fibrosis induced by the exposure of PM_2.5 and its molecular mechanism. Methods Seventy 7-week-old male C57BL/6 mice were randomly divided into four groups: control group (intratracheal instillation of normal saline + saline by gavage, n=25), Sal group (intratracheal instillation of normal saline + Sal 60 mg·kg⁻¹ by gavage, n=10), PM_2.5 group (intratracheal instillation of PM_2.5 5 mg·kg⁻¹ + saline by gavage, n=10), and Sal + PM_2.5 group (intratracheal instillation of PM_2.5 5 mg·kg⁻¹ +Sal 60 mg·kg⁻¹ by gavage, n=10). The mice were administered by gavage once daily, intratracheal instillation once every 3 d, and every 3 d constituted an experimental cycle. At the end of the 26-30th cycles, 3 mice in the control group and 3 mice in the PM_2.5 group were randomly sacrificed, and the lung tissues were collected for Masson staining to verify whether the pulmonary fibrosis model was successfully established. After 30 cycles, the model was successfully constructed. After 1 week of continuous observation, the mice were sacrificed, and the blood and lung tissues of the mice were collected to make lung tissue sections. Assay kits were correspondingly employed to detect oxidative stress indicators such as serum malondialdehyde (MDA) and superoxide dismutase (SOD). Western blotting was used to detect the expression of fibrosis-related proteins (Collagen-III, α-SMA), mitochondrial dynamics-related proteins (MFN1, Drp1), and mitophagy-related proteins (PINK1, Parkin, and LC3). Results Compared with the control group, the weight gain rate of the PM_2.5 group was slowed down (P<0.05), which was alleviated by the Sal intervention (P<0.05). The lung coefficient increased after the PM_2.5 exposure (P<0.05), which was alleviated by Sal intervention. Compared with the control group, the PM_2.5 group showed severe alveolar structure damage, inflammatory cell infiltration, and blue collagen deposition, and significantly increased the lung injury score, collagen volume fraction (CVF), Szapiel score, and Ashcroft score (P<0.05), as well as serum oxidative stress levels (P<0.05). The protein expression levels of Collagen-III, α-SMA, Drp1, PINK1, Parkin, and LC3 II/I were increased (P<0.05), and the expression of MFN1 was decreased (P<0.05). Compared with the PM_2.5 group, the Sal intervention alleviated lung injury, reduced inflammatory cell infiltration and collagen deposition, showing decreased lung injury score, CVF, Szapiel score, and Ashcroft score (P<0.05), and decreased serum oxidative stress levels (P<0.05); the protein expression levels of Collagen-III, α-SMA, PINK1, Parkin, and LC3 II/I were decreased (P<0.05), the expression level of Drp1 was decreased, and the expression level of MFN1 was increased. Conclusion In the process of pulmonary fibrosis induced by PM_2.5 exposure in mice, Sal may affect mitochondrial autophagy through PINK1/Parkin pathway and play a protective role. The specific mechanism needs to be further verified.

Objective To observe the occurrence of adverse reactions of ketogenic diet in patients with polycystic ovary syndrome(PCOS).Methods A total of 75 PCOS patients who started a keto-genic diet and adhered to follow-up from January to December 2023 in Beijing Shijitan Hospital Affilia-ted to Capital Medical University were selected as research objects.The occurrence of adverse reac-tions from the start of the ketogenic diet to 6 months after its completion was followed up.Results Af-ter implementing ketogenic diet intervention,the body weight,body fat percentage,visceral fat area,waist-to-hip ratio,body mass index,and incidence of menstrual disorders in PCOS patients decreased significantly from(84.50±12.85)kg,(41.87±5.25)％,(167.87±39.63)cm2,(0.95±0.04),(31.71±5.29)kg/m2,and 74.67％before intervention to(70.75±10.91)kg,(36.60±4.58)％,(122.78±36.94)cm2,(0.90±0.04),(26.65±4.35)kg/m2,and 21.33％after inter-vention(P＜0.05 or P＜0.01).The top three adverse reactions were hair loss(25.33％),sleep dis-turbances(16.00％),and weakness,dizziness and fatigue(13.33％).No new adverse reactions such as gallstones,urinary stones,hypoglycemia,or hypoalbuminemia were observed.Conclusion Keto-genic diet therapy for PCOS patients exhibits relatively high safety with no severe adverse reactions,but incidence of hair loss is relatively high.

BackgroundPostpartum depression （PPD） is a prevalent postpartum complications that significantly compromises women's psychological and physical well-being. Repetitive transcranial magnetic stimulation （rTMS）， a conventional neuromodulation technique， has been increasingly used in the treatment of PPD. However， high-quality evidence regarding its efficacy and safety remains limited. ObjectiveTo evaluate the efficacy and safety of rTMS in the treatment of PPD， thereby providing references for clinical treatment. MethodsDatabases including Cochrane Library， PubMed， Embase， CNKI， Wanfang， VIP and China Biology Medicine disc （CBM） were electronically searched for randomized controlled trials （RCTs） on rTMS for PPD， with the search spanning from database inception to February 8， 2025. Study quality was assessed using the Cochrane Handbook for Systematic Reviews of Interventions 5.0.1， and the certainty of evidence was graded according to the Grading of Recommendations Assessment， Development and Evaluation （GRADE） approach. Meta-analysis was conducted using RevMan 5.3 and Stata 12.0. The outcomes of the Meta-analysis included the total effective rate， Edinburgh Postnatal Depression Scale （EPDS） score， Hamilton Depression Rating Scale （HAMD） score， and adverse reactions （dizziness， headache， nausea， diarrhea， and the overall incidence of adverse reactions）. ResultsA total of 11 studies involving 729 patients with PPD were included. Meta-analysis results showed that the total effective rate in the study group was significantly higher than that in the control group （OR=5.54， 95% CI： 3.07–10.01， P<0.01）. Both EPDS score （SMD=-2.38， 95% CI： -3.39–-1.37， P<0.01） and HAMD score （SMD=2.53， 95% CI： 1.21–3.85， P<0.01） in the study group were significantly lower than those in the control group， with statistically significant differences. Comparisons between the study group and control group reveal no significant differences in the incidence of dizziness and headache （RR=1.47， 95% CI： 0.63–3.43， P>0.05）， nausea （RR=1.46， 95% CI： 0.55–3.86， P>0.05）， diarrhea （RR=0.71， 95% CI： 0.23–2.20， P>0.05）， and overall adverse reactions （RR=1.30， 95% CI： 0.79–2.15， P>0.05）. GRADE assessment rated the four indicators of dizziness and headache， diarrhea， overall incidence of adverse reactions， and EPDS score as "moderate-certainty evidence"， and rated the total effective rate， nausea， and the HAMD score as "low-certainty evidence". ConclusionrTMS demonstrates certain therapeutic efficacy for PPD， with a safety profile comparable to conventional treatment. ［Funded by Sichuan Psychological Society Research Planning Project （number， SCSXLXH202403099）； Guiding Science and Technology Plan Project of Guangyuan （number， 23ZDYF0095）］

Objective To investigate the effect of Euphorbia helioscopia on biological behaviors of non-small cell lung cancer(NSCLC)cells.Methods NSCLC cell lines PC-9 and A549 treated with different concentrations of Euphorbia helioscopia preparations were examined for changes in proliferation,apoptosis,invasion and migration using CCK-8 assay,colony formation assay,flow cytometry,wound healing assay and Transwell assay.Western blotting was performed to detect the changes in protein expressions of Bax,Bcl-2,E-cadherin,vimentin,MMP2,and MMP9 in the treated cells.PC-9 cells were injected subcutaneously into BALB/C nude mice to establish a nude mouse subcutaneous tumor model.According to the growth of subcutaneous tumors,mice were randomly divided into control group:gavaged daily with saline;Euphorbia helioscopia-treated group:gavaged daily with Euphorbia helioscopia 65 mg/mL,and Euphorbia helioscopia granules were dissolved in saline;cisplatin-treated group:injected intraperitoneally with cisplatin 4 mg/kg every 5 days,6 mice per group.The subcutaneous tumor volume and mass changes of mice were measured,and the toxic effects of Euphorbia helioscopia on heart,liver,spleen,lung and kidney as well as the therapeutic effects of Euphorbia helioscopia were observed in the mice bearing tumor.Results Euphorbia helioscopia granules concentration-dependently inhibited the proliferation and survival of PC-9 and A549 cells,significantly promoted cell apoptosis,suppressed invasion and migration abilities of the cells,up-regulated the expression levels of E-cadherin and Bax,and down-regulated the expressions of Bcl-2,vimentin,MMP2,and MMP9.In the tumor-bearing mice,treatment with Euphorbia helioscopia significantly inhibited tumor growth without producing obvious toxicity in the vital organs.Conclusion Euphorbia helioscopia can inhibit proliferation,invasion,and migration and induces apoptosis of NSCLC cells in vitro.

OBJECTIVE To study the correlation between the early postoperative symptom groups and quality of life in patients with thyroid cancer. METHODS From July 2023 to October 2023,patients after thyroid cancer at 1 to 3 days in Beijing and Shanxi Hospitals were selected,and the general data questionnaire,thyroid cancer quality of life scale(EORTC QLQ-THY 34) and quality of life core questionnaire(EORTC QLQ-C30) were used. Exploration factors were used to extract the early symptom group of thyroid cancer patients,investigate the scores of the quality of life,and conduct Pearson correlation analysis. RESULTS Factor analysis extracted four symptom groups:throat-voice symptom group,limb numbness-emotional symptom group,swallowing related symptom group,physical stress symptom group,The cumulative variance contribution rate was 64.93％. The overall health status score of patients with thyroid cancer in the early postoperative stage was 5.12±1.65,it was below the normal level. In the functional domain,the cognitive function score was 3.74±0.45,emotional function score 3.21±0.43,social function 2.96±0.76,and role function 2.66±0.73. The highest scores in the symptom domain were fatigue 1.77±0.39 and pain 1.75±0.50. The symptom group scores were negatively correlated with the scores of all dimensions of quality of life(P<0.05). Each symptom group and each dimension of the quality of life showed significant correlation. The throat-voice symptom group had the strongest correlation with sleep disturbance and role function(r=0.646,r=-0.561). Limb numbness-emotional symptom group was most associated with social functioning,insomnia,and general health(r=-0.538,r=0.529,r=-0.529). Groups of abnormal swallowing symptoms were most associated with physical function,sleep disturbance,and fatigue(r=-0.491,r=0.491,r=0.476),Groups of physical stress symptoms were most associated with physical function and fatigue(r=-0.523,r=-0.520). Sleep disorder had strong associations with each symptom group(r>0.400). CONCLUSION There are four symptom groups in thyroid cancer patients in the early postoperative period,which affect the quality of life of the patients after surgery. Medical staff should timely evaluate and identify the relevant symptoms of the patients after surgery,and conduct effective management,so as to improve the quality of life of the patients after surgery and promote recovery.

Objective To investigate the effect of Euphorbia helioscopia on biological behaviors of non-small cell lung cancer(NSCLC)cells.Methods NSCLC cell lines PC-9 and A549 treated with different concentrations of Euphorbia helioscopia preparations were examined for changes in proliferation,apoptosis,invasion and migration using CCK-8 assay,colony formation assay,flow cytometry,wound healing assay and Transwell assay.Western blotting was performed to detect the changes in protein expressions of Bax,Bcl-2,E-cadherin,vimentin,MMP2,and MMP9 in the treated cells.PC-9 cells were injected subcutaneously into BALB/C nude mice to establish a nude mouse subcutaneous tumor model.According to the growth of subcutaneous tumors,mice were randomly divided into control group:gavaged daily with saline;Euphorbia helioscopia-treated group:gavaged daily with Euphorbia helioscopia 65 mg/mL,and Euphorbia helioscopia granules were dissolved in saline;cisplatin-treated group:injected intraperitoneally with cisplatin 4 mg/kg every 5 days,6 mice per group.The subcutaneous tumor volume and mass changes of mice were measured,and the toxic effects of Euphorbia helioscopia on heart,liver,spleen,lung and kidney as well as the therapeutic effects of Euphorbia helioscopia were observed in the mice bearing tumor.Results Euphorbia helioscopia granules concentration-dependently inhibited the proliferation and survival of PC-9 and A549 cells,significantly promoted cell apoptosis,suppressed invasion and migration abilities of the cells,up-regulated the expression levels of E-cadherin and Bax,and down-regulated the expressions of Bcl-2,vimentin,MMP2,and MMP9.In the tumor-bearing mice,treatment with Euphorbia helioscopia significantly inhibited tumor growth without producing obvious toxicity in the vital organs.Conclusion Euphorbia helioscopia can inhibit proliferation,invasion,and migration and induces apoptosis of NSCLC cells in vitro.

Background Salidroside (SAL) has a protective effect on multiple organ systems. Exposure to fine particulate matter (PM_2.5) in the atmosphere may lead to disruptions in gut microbiota and impact intestinal health. The regulatory effect of SAL on the gut microbiota of mice exposed to PM_2.5 requires further investigation. Objective To evaluate gut microbiota disruption in mice after being exposed to PM_2.5 and the potential effect of SAL. Methods Forty male C57BL/6 mice, aged 6 to 8 weeks, were randomly divided into four groups: a control group, an SAL group, a PM_2.5 group, and an SAL+PM_2.5 group, each containing 10 mice. In the SAL group and the SAL+PM_2.5 group, the mice were administered SAL (60 mg·kg⁻¹) by gavage, while in the control group and the PM_2.5 group, sterile saline (10 mL·kg⁻¹) was administered by gavage. In the PM_2.5 group and the SAL+PM_2.5 group, PM_2.5 suspension (8 mg·kg⁻¹) was intratracheally instilled, and in the control group and SAL group, sterile saline (1.5 mL·kg⁻¹) was intratracheally administered. Each experiment cycle spanned 2 d, with a total of 10 cycles conducted over 20 d. Histopathological changes in the ileum tissue of the mice were observed after HE staining. Colon contents were collected for gut microbiota sequencing and short-chain fatty acids (SCFAs) measurements. Results The PM_2.5 group showed infiltration of inflammatory cells in the ileum tissue, while the SAL+PM_2.5 group exhibited only a small amount of inflammatory cell infiltration. Compared to the control group, the PM_2.5 group showed decreased Shannon index (P<0.05) and increased Simpson index (P<0.05), indicating that the diversity of gut microbiota in this group was decreased; the SAL+PM_2.5 group showed increased Shannon index compared to the PM_2.5 group (P<0.05) and decreased Simpson index (P<0.05), indicating that the diversity of gut microbiota in mice intervened with SAL was increased. The principal coordinates analysis (PCoA) revealed a significant separation between the PM_2.5 group and the control group, while the separation trend was less evident among the control group, the SAL group, and the SAL+PM_2.5 group. The unweighted pair-group method with arithmetic means (UPGMA) clustering tree results showed that the control group and the SAL group clustered together first, followed by clustering with the SAL+PM_2.5 group, and finally, the three groups clustered with the PM_2.5 group. The PCoA and UPGMA clustering results indicated that the uniformity and similarity of the microbiota in the PM_2.5 group were significantly decreased. Compared to the control group, the PM_2.5 group showed decreased abundance of phylum Bacteroidetes and Candidatus_Saccharimonas (P<0.05) and increased abundance of phylum Proteobacteria, genus Escherichia, genus Bacteroides, genus Prevotella, genus Enterococcus, and genus Proteus (P<0.05). Compared to the PM_2.5 group, the SAL+PM_2.5 group showed decreased abundance of phylum Proteobacteria, phylum Actinobacteria, genus Prevotella, and genus Proteus (P<0.05), and increased abundance of Candidatus_Saccharimonas (P<0.05). The PM_2.5 group showed reduced levels of propionic acid, valeric acid, and hexanoic acid compared to the control group (P<0.05), while the SAL+PM_2.5 group showed increased levels of propionic acid, isobutyric acid, butyric acid, valeric acid, and hexanoic acid compared to the PM_2.5 group (P<0.05). Conclusion Exposure to PM_2.5 can cause pathological alterations, microbial dysbiosis, and disturbing production of SCFAs in intestinal tissue in mice. However, SAL can provide a certain degree of protective effect against these changes.