1.Huazhuo Jiedu Prescription Treats Ulcerative Colitis by Inhibiting Excessive Mitophagy via PINK1/Parkin Signaling Pathway
Haofeng ZHANG ; Jinye ZHOU ; Ziwei LIU ; Yican WANG ; Yirui CHENG ; Zheng ZHI ; Qian YANG ; Bolin LI
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(11):182-189
ObjectiveTo investigate the mechanism of Huazhuo Jiedu prescription in treating ulcerative colitis (UC) by regulating mitophagy. MethodsThe genes related to mitophagy and UC were retrieved from GeneCards, and then the common genes of mitophagy and UC were analyzed by metascape to identify the genes related to mitophagy in UC. Animal experiments were carried out to decipher the mechanism by which Huazhuo Jiedu prescription treated UC by regulating mitophagy. Sixty C57BL/6 male mice were randomized into normal, model, high-, medium-, and low-dose (50, 25, 12.5 g·kg-1, respectively) Huazhuo Jiedu prescription, and mesalazine (0.52 g·kg-1·d-1) groups, with 10 mice in each group. After successful modeling by the dextran sulfate sodium-free drinking method, the colonic mucosal damage was observed by hematoxylin-eosin staining, and the ultracellular structure of colon mucosa was observed by transmission electron microscopy. The expression levels of mitophagy-related proteins PTEN-induced putative kinase 1 (PINK1) and Parkin protein were determined by Western blot. The expression of prohibitin 2 (PHB2), ubiquitin-specific protease 15 (USP15), ubiquitin-specific protease 30 (USP30) in the colon tissue was detected by immunofluorescence (IF). ResultsAll the drug intervention groups showed ameliorated pathological manifestations of the colonic mucosa and improved mitochondrial structures in UC mice. Compared with the normal group, the model group demonstrated up-regulated protein levels of PINK1 and Parkin (P<0.05), enhanced average fluorescence intensity of PHB2 (P<0.05), and weakened average fluorescence intensity of USP15 and USP30 (P<0.05). Compared with the model group, the mesalazine group and the high- and medium-dose Huazhuo Jiedu prescription groups showcased down-regulated protein levels of PINK1 and Parkin (P<0.05), decreased average fluorescence intensity of PHB2 (P<0.05), and enhanced average fluorescence intensity of USP15 and USP30 (P<0.05). The low-dose Huazhuo Jiedu prescription group showed down-regulated protein levels of PINK1 and Parkin (P<0.05), weakened average fluorescence intensity of PHB2 (P<0.05), and enhanced average fluorescence intensity of USP15 and USP30 (P<0.05). ConclusionHuazhuo Jiedu prescription can attenuate the intestinal mucosal injury and improve the mitochondrial cell ultrastructure in UC mice by regulating the expression of PINK1-Parkin pathway and inhibiting excessive mitophagy.
2.Huazhuo Jiedu Prescription Treats Ulcerative Colitis by Inhibiting Excessive Mitophagy via PINK1/Parkin Signaling Pathway
Haofeng ZHANG ; Jinye ZHOU ; Ziwei LIU ; Yican WANG ; Yirui CHENG ; Zheng ZHI ; Qian YANG ; Bolin LI
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(11):182-189
ObjectiveTo investigate the mechanism of Huazhuo Jiedu prescription in treating ulcerative colitis (UC) by regulating mitophagy. MethodsThe genes related to mitophagy and UC were retrieved from GeneCards, and then the common genes of mitophagy and UC were analyzed by metascape to identify the genes related to mitophagy in UC. Animal experiments were carried out to decipher the mechanism by which Huazhuo Jiedu prescription treated UC by regulating mitophagy. Sixty C57BL/6 male mice were randomized into normal, model, high-, medium-, and low-dose (50, 25, 12.5 g·kg-1, respectively) Huazhuo Jiedu prescription, and mesalazine (0.52 g·kg-1·d-1) groups, with 10 mice in each group. After successful modeling by the dextran sulfate sodium-free drinking method, the colonic mucosal damage was observed by hematoxylin-eosin staining, and the ultracellular structure of colon mucosa was observed by transmission electron microscopy. The expression levels of mitophagy-related proteins PTEN-induced putative kinase 1 (PINK1) and Parkin protein were determined by Western blot. The expression of prohibitin 2 (PHB2), ubiquitin-specific protease 15 (USP15), ubiquitin-specific protease 30 (USP30) in the colon tissue was detected by immunofluorescence (IF). ResultsAll the drug intervention groups showed ameliorated pathological manifestations of the colonic mucosa and improved mitochondrial structures in UC mice. Compared with the normal group, the model group demonstrated up-regulated protein levels of PINK1 and Parkin (P<0.05), enhanced average fluorescence intensity of PHB2 (P<0.05), and weakened average fluorescence intensity of USP15 and USP30 (P<0.05). Compared with the model group, the mesalazine group and the high- and medium-dose Huazhuo Jiedu prescription groups showcased down-regulated protein levels of PINK1 and Parkin (P<0.05), decreased average fluorescence intensity of PHB2 (P<0.05), and enhanced average fluorescence intensity of USP15 and USP30 (P<0.05). The low-dose Huazhuo Jiedu prescription group showed down-regulated protein levels of PINK1 and Parkin (P<0.05), weakened average fluorescence intensity of PHB2 (P<0.05), and enhanced average fluorescence intensity of USP15 and USP30 (P<0.05). ConclusionHuazhuo Jiedu prescription can attenuate the intestinal mucosal injury and improve the mitochondrial cell ultrastructure in UC mice by regulating the expression of PINK1-Parkin pathway and inhibiting excessive mitophagy.
3.Effect of Xianglian Huazhuo Prescription on Hedgehog Signaling Pathway in Rats with Chronic Atrophic Gastritis
Jinye ZHOU ; Haofeng ZHANG ; Ziwei LIU ; Yican WANG ; Yanru CAI ; Yuxi GUO ; Jie WANG ; Zheng ZHI ; Qian YANG ; Bolin LI
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(18):41-47
ObjectiveTo explore the therapeutic effect and mechanism of Xianglian Huazhuo prescription on chronic atrophic gastritis (CAG) in rats based on the Hedgehog signaling pathway. MethodsThe CAG rat model was established by sodium salicylate, N-methyl-N′-nitro-N-nitroguanidine (MNNG), and irregular feeding. The successfully modeled rats were randomly divided into a model group (180 mg·L-1), a moradan group (1.4 g·kg-1), and Xianglian Huazhuo Prescription groups with high, medium, and low doses (36, 9, 18 g·kg-1), followed by drug intervention. Hematoxylin-eosin (HE) staining was used to observe morphological changes in the gastric mucosa. Transmission electron microscopy was used to observe the ultrastructure of gastric mucosa cells. Real-time quantitative polymerase chain reaction (Real-time PCR) was used to detect the mRNA expression of Sonic Hedgehog (Shh), Patched 1 (Ptch1), and Glioma-associated oncogene homolog 1 (Gli1). Western blot was used to detect the protein expression levels of Shh, Ptch1, and Gli1 in the gastric mucosa. Immunohistochemistry was used to observe the protein expression of the epithelial marker E-cadherin. ResultsCompared with the normal group, the CAG model group showed a reduction in gastric mucosal intrinsic glands and infiltration of inflammatory cells. The ultrastructure of gastric mucosal cells showed nuclear pyknosis, fewer mitochondria, and abnormal mitochondrial structure. The mRNA and protein expression of Shh, Ptch1, and Gli1 in the gastric mucosa were significantly decreased (P<0.05), and E-cadherin protein expression was decreased. Compared with the model group, the intervention groups showed varying degrees of improvement in histopathological morphology and cellular ultrastructure. The mRNA and protein expression of Shh, Ptch1, Gli1, and E-cadherin increased to varying degrees. Xianglian Huazhuo Prescription upregulated the expression of key Hedgehog pathway factors and E-cadherin at both the mRNA and protein levels (P<0.05). ConclusionXianglian Huazhuo prescription has a therapeutic effect on CAG in rats, and its mechanism may be related to activation of the Hedgehog signaling pathway and inhibition of epithelial-mesenchymal transition (EMT).
4.Transplantation of menstrual blood-derived endometrial stem cells allevi-ates chemotherapy-induced intestinal injury and flora imbalance in mice through immunomodulation
Qin LIU ; Mengyuan CHANG ; Haofeng SONG ; Chenxu DU ; Yonghai LI ; Shenghui ZHANG ; Yanli LIU ; Juntang LIN
Chinese Journal of Pathophysiology 2024;40(2):301-308
AIM:To investigate the therapeutic effect of menstrual blood-derived endometrial stem cells(MenSCs)on chemotherapy-induced intestinal mucositis and flora disorders in mice,and to explore the potential mecha-nism.METHODS:The mice were randomly divided into 3 groups including normal treatment,cisplatin(Cis)treatment and Cis+MenSC treatment,with 10 mice in each group.To induce intestinal mucositis,the mice were treated with Cis(2 mg·kg-1·d-1)by intraperitoneal injection for 5 consecutive days.Control mice for normal group were received equal vol-umes of normal saline.For Cis+MenSC treatment,MenSCs(1×106)was transplanted into the mice of Cis treated mice through tail vein.The performances and weight changes of mice were examined during the experiment.After the treat-ment,the small intestine and colon were isolated for subsequent HE staining,the ratio of F4/80 and IL-6 positive cells in small intestine were detected by immunohistochemical staining,and the expression of tight junction,inflammation and apoptosis related proteins was detected by Western blot.16S rDNA amplicon sequencing was performed to detect the diver-sity and richness of intestinal flora in mice.RESULTS:Compared to the Cis group,the MenSCs-treated mice showed sig-nificantly increased body weight,relieved intestinal lymphocytes infiltration,alleviated intestinal villous edema,and or-derly arranged glands in intestinal tissues.Further analysis indicated that MenSCs transplantation significantly up-regulat-ed the expression of intestinal tight junction related proteins ZO-1 and occludin in Cis-treated mice(P<0.05).Subse-quently,MenSCs transplantation significantly inhibited the macrophages infiltration in intestinal tissues(P<0.01),down-regulated the expression of pro-inflammatory factors IL-1 and IL-6 and pro-apoptotic protein Bax(P<0.01),while up-regu-lated anti-inflammatory factor IL-10 and anti-apoptotic protein Bcl-2(P<0.01).Additionally,further microflora sequenc-ing indicated that MenSCs transplantation prevented mice from Cis-induced intestinal flora disorder,and significantly re-duced the abundance of harmful bacteria such as isenbergiella tayi and Anaerotruncus colihominis(P<0.01).At the same time,the abundance of beneficial bacteria Lactobacillus apodemi was increased(P<0.05),thereby restoring the composi-tion and function of healthy intestinal flora.CONCLUSION:MenSCs transplantation alleviates the chemotherapy-in-duced damage of intestinal structure,relieves the symptoms of chemotherapy-induced mucositis and restores the homeosta-sis of intestinal flora in mice.
5.Risk factors and prognosis of recurrence within 6 months after radical resection of intrahepatic cholangiocarcinoma
Zhenwei YANG ; Pengyu CHEN ; Hao YUAN ; Zuochao QI ; Guan HUANG ; Haofeng ZHANG ; Bo MENG ; Xianzhou ZHANG ; Haibo YU
Chinese Journal of General Surgery 2024;39(2):99-104
Objective:To explore the relevant risk factors and prognosis of patients with intrahepatic cholangiocarcinoma (ICC) who experienced recurrence within 6 months after surgeryMethods:This retrospective study included a total of 259 patients with ICC a treated at He'nan Provincial People's Hospital and He'nan Cancer Hospital from Jan 2018 to Jan 2020. The clinical and pathological data ,differences between the group with recurrence within 6 months and the group without recurrence within 6 months were compared using the chi-square test. Logistic regression analysis was used to determine the relevant risk factors for recurrence within 6 months. Kaplan-Meier method was used to construct survival and recurrence curves, and survival rates were calculated.Results:The overall survival and recurrence-free survival of patients in the group with recurrence within 6 months were significantly shorter. CA19-9, tumor longitudinal diameter, microvascular invasion, and neural invasion were identified as independent risk factors for recurrence within 6 months after ICC surgery ( P<0.001). Conclusion:The patient population experiencing recurrence within 6 months after ICC surgery has an extremely poor prognosis and possesses a specific tumor microenvironment. CA19-9, tumor longitudinal diameter, microvascular invasion, and neural invasion were identified as independent risk factors for recurrence within 6 months after ICC surgery.
6.The effect of Ba Duan Jin on the balance of community-dwelling older adults: a cluster randomized control trial
Leilei DUAN ; Yubin ZHAO ; Yuliang ER ; Pengpeng YE ; Wei WANG ; Xin GAO ; Xiao DENG ; Ye JIN ; Yuan WANG ; Cuirong JI ; Xinyan MA ; Cong GAO ; Yuhong ZHAO ; Suqiu ZHU ; Shuzhen SU ; Xin'e GUO ; Juanjuan PENG ; Yan YU ; Chen YANG ; Yaya SU ; Ming ZHAO ; Lihua GUO ; Yiping WU ; Yangnu LUO ; Ruilin MENG ; Haofeng XU ; Huazhang LIU ; Huihong RUAN ; Bo XIE ; Huimin ZHANG ; Yuhua LIAO ; Yan CHEN ; Linhong WANG
Chinese Journal of Epidemiology 2024;45(2):250-256
Objective:To assess the effectiveness of a 6-month Ba Duan Jin exercise program in improving the balance of community-dwelling older adults.Methods:A two arms, parallel-group, cluster randomized controlled trial was conducted in 1 028 community residents aged 60-80 years in 40 communities in 5 provinces of China. Participants in the intervention group (20 communities, 523 people) received Ba Duan Jin exercise 5 days/week, 1 hour/day for 6 months, and three times of falls prevention health education, and the control group (20 communities, 505 people) received falls prevention health education same as the intervention group. The Berg balance scale (BBS) score was the leading outcome indicator, and the secondary outcome indicators included the length of time of standing on one foot (with eyes open and closed), standing in a tandem stance (with eyes open and closed), the closed circle test, and the timed up to test.Results:A total of 1 028 participants were included in the final analysis, including 731 women (71.11%) and 297 men (28.89%), and the age was (69.87±5.67) years. After the 3-month intervention, compared with the baseline data, the BBS score of the intervention group was significantly higher than the control group by 3.05 (95% CI: 2.23-3.88) points ( P<0.001). After the 6-month intervention, compared with the baseline data, the BBS score of the intervention group was significantly higher than the control group by 4.70 (95% CI: 4.03-5.37) points ( P<0.001). Ba Duan Jin showed significant improvement ( P<0.05) in all secondary outcomes after 6 months of exercise in the intervention group compared with the control group. Conclusions:This study showed that Ba Duan Jin exercise can improve balance in community-dwelling older adults aged 60-80. The longer the exercise time, the better the improvement.
7.Risk factors analysis and prediction model construction of major adverse cardiovascular events in pregnant women with valvular heart disease
Jiaqi ZENG ; Haofeng ZHANG ; Jun ZHANG ; Dong YANG ; Dawei ZHANG ; Zhaoliang BAO
Chinese Journal of Obstetrics and Gynecology 2024;59(8):591-599
Objective:To analysis the risk factors for major adverse cardiovascular event (MACE) in pregnant women with valvular heart disease (VHD) and to construct a risk prediction model.Methods:The clinical data of 245 pregnant women with VHD who were hospitalized in Beijing Anzhen Hospital from January 1, 2012, to June 1, 2023 were retrospectively analyzed, including general information, pre-pregnancy and pregnancy-associated cardiac conditions, and MACE. Univariate analysis and logistic regression models were employed to identify risk factors for MACE during pregnancy among pregnant women with VHD. Furthermore, a predictive model was constructed and internal validation was conducted using bootstrap techniques.Results:(1) Among 245 pregnant women with VHD, the incidence of MACE was 18.0% (44/245), and the most common MACE was heart failure (61.4%, 27/44). The mitral valve was the most frequently affected valve (64.9%, 159/245). Prior to pregnancy, the most common type of valve surgery undertaken was mechanical valve replacement, representing 31.4% (77/245) of surgeries. In contrast, among those pregnant women who did not undergo valve surgery before pregnancy, the most common lesion type was mitral regurgitation (17.6%, 43/245). (2) Comparing the maternal and infant outcomes of warfarin, low molecular weight heparin (LMWH) and LMWH sequential with warfarin, the fetal loss rate (36%, 15/42) and malformation rate (7%, 3/42) were the highest, but the MACE rate (12%, 5/42) was the lowest in warfarin group. The fetal loss rate (1/19), malformation rate (1/19) and artificial valve thrombosis rate (0) of LMWH sequential with warfarin were the lowest, and the fetal loss rate and artificial valve thrombosis rate of the three anticoagulation methods were statistically significant (all P<0.05). (3) There were no significant differences in gestational age, age of diagnosis of heart disease, weight at delivery, pre-pregnancy body mass index, proportion of multiparous women and chronic medical history between women with MACE and those without MACE (all P>0.05). (4) Binary logistic regression analysis identified the following as risk factors for MACE during the second trimester of pregnancy among pregnant women with VHD: pre-pregnancy cardiac symptoms, history of corrective surgery for congenital heart disease, pregnancy risk grade Ⅴ, anticoagulation with LMWH during pregnancy, and arrhythmia (all P<0.05). Based on the results of multivariate analysis, a receiver operating characteristic curve was constructed, with an area under the curve of 0.837, indicating good discriminative ability. The calibration plot demonstrated a close alignment between the standard curve and the calibration prediction curve, suggesting excellent calibration of the model. Conclusions:Pregnant women with VHD are at a high risk of experiencing MACE during gestation. Five risk factors, including pre-pregnancy cardiac symptoms, history of corrective surgery for congenital heart disease, pregnancy risk grade Ⅴ, anticoagulation with LMWH, and arrhythmia, could aid in identifying high-risk pregnant women.
8.Construction and validation of a machine learning model for preoperative prediction of perineural invasion status in intrahepatic cholangiocarcinoma
Zuochao QI ; Zhenwei YANG ; Qingshan LI ; Hao YUAN ; Pengyu CHEN ; Haofeng ZHANG ; Yanbo WANG ; Dongxiao LI ; Bo MENG ; Haibo YU ; Deyu LI
Chinese Journal of Hepatobiliary Surgery 2024;30(6):424-430
Objective:To construct and validate a machine learning model for preoperative prediction of perineural invasion (PNI) status in intrahepatic cholangiocarcinoma (ICC).Methods:Clincial data of 329 patients, including 245 admitted to Zhengzhou University People's Hospital from January 2018 to June 2023 and 84 admitted to the Affiliated Cancer Hospital of Zhengzhou University from January 2013 to January 2020 were retrospectively analyzed. Patients were divided into a training set ( n=231) and a validation set ( n=98). Clinicopathological data including age, gender, hepatitis B virus (HBV) infection status were collected. Predictive variables were determined using least absolute shrinkage and selection operator (LASSO) regression analysis. Six machine learning algorithms including random forest (RF), logistic regression, and linear kernel-based support vector machine were selected to construct the preoperative prediction model for PNI in ICC. Performance metrics of the model were calculated using a confusion matrix, and the final model was selected. The model performance was evaluated in the validation set. Calibration curves were plotted to evaluate the final model, and a Pareto chart was used to visualize the importance of predictive variables. Results:LASSO regression identified nine predictive variables included in the prediction model, including carbohydrate antigen 19-9 (CA19-9), HBV infection status, alkaline phosphatase, alanine aminotransferase, prothrombin time, total bilirubin, albumin, neutrophil times gamma-glutamyl transferase to lymphocyte ratio, and tumor burden score. Among the trained six models, the area under the curve (AUC) of the RF model was 0.909, with a sensitivity of 0.842 and an accuracy of 0.870. Compared with the AUC of the RF model, the AUCs of the other 5 models were lower (all P<0.05). The AUC of the RF model for predicting PNI in ICC in validation set was 0.736. Calibration curves showed good fit of the RF model's prediction of PNI in ICC in both training and validation sets. The Pareto chart showed that CA19-9 was the most important predictive variable in the model, followed by HBV infection status. Conclusion:The machine learning model based on the RF algorithm has a high accuracy in preoperative prediction of PNI status in ICC.
9.The predictive value of systemic immune-inflammatory response index combined with tumor burden score in the prognosis of patients after radical resection for intrahepatic cholangiocarcinoma
Hao YUAN ; Haofeng ZHANG ; Qingshan LI ; Guan HUANG ; Zhenwei YANG ; Pengyu CHEN ; Zuochao QI ; Chenxi XIE ; Bo MENG ; Haibo YU
Chinese Journal of Digestion 2024;44(4):257-265
Objective:To explore the prognostic value of systemic immune-inflammatory index(SII)combined with tumor burden score (TBS) (hereinafter referred to as STS) in patients with intrahepatic cholangiocarcinoma (ICC) after radical resection, and to construct a nomogram model.Methods:The clinical data (including the degree of tumor differentiation, vascular cancer thrombus, and lymph node metastasis, etc.) of 258 ICC patients who received radical resection at People′s Hospital of Zhengzhou University (170 cases, training set) and Cancer Hospital of Zhengzhou University (88 cases, validation set) from January 1, 2016 to January 31, 2020 were retrospectively analyzed and graded by SII, TBS and STS. Multivariate Cox regression analysis were used to identify independent factors affecting the prognosis of patients with ICC. Kaplan-Meier survival curve and receiver operating characteristic curve (ROC) were drawn to evaluate the predictive efficiency of SII, TBS and STS in the overall survival of patients with ICC after radical resection. The nomogram prediction model was constructed and evaluate the performance of nomogram model using consistency index (C-index) and calibration curve.Results:Among 170 ICC patients in the training set, there were 106 cases of SII grade 1 and 64 cases of SII grade 2; 137 cases of TBS grade 1 and 33 cases of TBS grade 2; and 98 cases of STS grade 1, 47 cases of STS grade 2, and 25 cases of STS grade 3. Among 88 ICC patients in the validation set, there were 33 cases of SII grade 1 and 55 cases of SII grade 2; 66 cases of TBS grade 1 and 22 cases of TBS grade 2; and 30 case of STS grade 1, 39 cases of TBS grade 2, and 19 cases of TBS grade 3.The multivariate Cox regression analysis showed that tumor differentiation degree (highly differentiated vs. moderately differentiated HR=0.157, 95% confidence interval(95% CI) 0.045 to 0.546, highly differentiated vs. poorly differentiated HR=0.452, 95% CI 0.273 to 0.750), STS (grade 3 vs. grade 2 HR=1.966, 95% CI 1.148 to 3.469; grade 3 vs. grade 1 HR=1.405, 95% CI 0.890 to 2.216), vascular cancer thrombus ( HR=2.006, 95% CI 1.313 to 3.066), nerve invasion ( HR=1.865, 95% CI 1.221 to 2.850), and lymph node metastasis ( HR=1.802, 95% CI 1.121 to 2.896) were independent influencing factors of overall survival in ICC patients after radical resection (all P<0.05). The Kaplan-Meier survival curve showed that SII, TBS, and STS were independent influencing factors of overall survival in ICC patients (all P<0.05). The results of ROC analysis showed that the areas under the curve of SII, TBS and STS in predicting overall survival of ICC patients after radical resection were 0.566 (95% CI 0.479 to 0.652), 0.585 (95% CI 0.499 to 0.672), and 0.657 (95% CI 0.522 to 0.692), respectively. Tumor differentiation, vascular tumor thrombus, nerve invassion, lymph node metastasis, and STS were included to constract the nomogram model. The C-indexes of the training set and validation set based on the nomogram model were 0.792 (95% CI 0.699 to 0.825) and 0.776 (95% CI 0.716 to 0.833), respectively. The calibration curves of the survival rate of the training set and the validation set were close to the reference lines, and the nomogram model had better predictive ability in both the training set and the validation set. Conclusions:Preoperative STS grading is an effective and practical predictor of overall survival in ICC patients after radical section. Compared with SII and TBS alone, it has better predictive value for the prognosis of patients with ICC.
10.Air quality of metro system in a northwestern city of China from 2021 to 2022
Ying ZHANG ; Yuxi MA ; Yong ZHANG ; ABULIMITI ABABAIKELI ; Wenyuan HAO ; Haofeng YANG
Journal of Environmental and Occupational Medicine 2023;40(11):1290-1296
Background Most metro system are underground, airtight, with inadequate ventilation and massive gatherings, posing health risks to metro riders. Objective To evaluate air quality of Metro Line 1 in a city, and provide suggestions and basis for preventing harmful factors and protecting the health of passengers. Methods Station halls, station platforms, and metro carriages of Metro Line 1 in a city were monitored in summer (from July to August in 2021) and winter (from January to February in 2022). Six metro stations were selected by stratified sampling. Each station and carriage were monitored for three consecutive days in rush hours (9:00–11:00 and 19:00–21:00) and non-rush hours (11:00–13:00), with the same monitoring frequency. The monitored indicators were physical factors (temperature, relative humidity, wind speed, illumination, and noise), chemical factors (carbon monoxide, carbon dioxide, inhalable particles, formaldehyde, benzene, toluene, xylene, ammonia, and ozone), biological factor (airborne total bacterial count), and radiation factor (radon). The monitoring results were compared by location, time period, and season. Results According to the Hygienic indicators and limits for public places (GB 37488—2019), the selected physical factors did not meet the standard, especially the temperature and relative humidity of station hall and platform, and wind speed and noise of carriage. The results of physical factors varied significantly by location (P<0.05). In summer, the temperature of carriage [M (P25, P75), 23.9 (23.3, 24.6)℃] was the lowest, and the wind speed [0.78 (0.37, 1.11) m·s−1] and noise [76.0 (72.0, 80.3) dB] of carriage were the highest; in winter, the temperatures of station hall and platform were the lowest [16.2 (13.2, 17.2)℃ and 16.2 (13.4, 17.0)℃, respectively], the relative humidity of carriage [26.4% (24.2%, 27.9%)] was the lowest, and the wind speed and noise of carriage were the highest [0.83 (0.47, 1.18) m·s−1 and 74.5 (70.1, 78.3) dB, respectively]. The physical factors varied significantly by time period (P<0.05). In summer, the temperature was the lowest during morning rush hours [24.0 (23.0, 24.8)℃] and non-rush hours [24.2 (23.2, 24.9)℃], and the relative humidity during evening rush hours was the lowest [41.9% (37.0%, 47.8%)]; in winter, the temperature was the lowest during morning and evening rush hours [16.8 (13.4, 19.7)℃ and 16.5 (15.1, 19.4)℃, respectively], the relative humidity during the non-rush period was the lowest [26.8% (24.7%, 28.6%)], and the wind speed during evening rush hours was the highest [0.28 (0.19, 0.51) m·s−1]. All measured chemical factors, biological factor, and radiation factor met the national standard (GB 37488—2019). Conclusion The chemical, biological, and radiative factors are complied with the national standard (GB 37488—2019) except physical factors such as temperature, relative humidity, wind speed, and noise. We suggest that the metro operators make full use of air conditioning system in combination with humidifiers to better regulate temperature and relative humidity, and .arrange working hours reasonably and provide noise-proof earplugs for carriage staff to protect against noise hazard.

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