ObjectiveTo explore the effects of Kaixuan Jiedu core prescription （KXJD） on sphingolipid metabolism in the mouse model of imiquimod-induced psoriasis-like skin lesions. MethodsThirty-seven male C57BL/6J mice were randomly assigned into five groups： healthy control （n=11）， model （n=11）， methotrexate （MTX， n=5）， low-dose （15.21 g·kg^-1） KXJD （n=5）， and high-dose （30.42 g·kg^-1） KXJD （n=5）. Psoriasis-like skin lesions were induced in mice with 62.5 mg 5% imiquimod cream applied on the back. The KXJD groups and MTX group were treated with 0.2 mL corresponding decoction and MTX， respectively， by gavage daily， while the other groups were given an equal volume of normal saline by the same way. After 5 days of treatment， back skin lesions were collected. Firstly， healthy control and model mice were selected for tandem mass tag （TMT） quantitative proteomics （control vs model=3 vs 3） and targeted lipid metabolomics （control vs model=11 vs 11）. Then， the binding degree between core components and target proteins was predicted via network pharmacology and molecular docking. Finally， an animal experiment was performed to decipher the specific regulation mechanism of KXJD on sphingolipid metabolism. Immunohistochemistry was employed to determine the expression level of sphingosine-1-phosphate （S1P）， and Western blot was employed to determine the expression levels of sphingosine kinase 2 （SPHK2） and monocyte chemotactic protein-1 （MCP-1）. ResultsTMT proteomics and targeted lipid metabolomics suggested that sphingolipid metabolism was active in the psoriatic skin， and key proteases ［serine palmitoyltransferase， long chain base subunit 2 （SPTLC2）， SPHK2， delta（4）-desaturase sphingolipid 1 （Degs1）， and ceramide synthase 4 （CerS4）］ and 8 sphingolipid metabolites （including ceramides， sphingol， sphingomyelin， and glycosphingolipid） expressed abnormally （P<0.05） compared with those in the healthy skin. The molecular docking results indicated that the binding energy between the active components （quercetin， kaempferol， and luteolin） in KXJD and key proteins involved in sphingolipid metabolism was less than-8 kal·mol^-1. Further experimental verification showed elevated expression levels of SPHK2， S1P， and MCP-1 in psoriatic skin compared with healthy skin （P<0.05）， and KXJD down-regulated the expression levels of SPHK2， S1P， and MCP-1 compared with the model group （P<0.05）. ConclusionThis study indicates that there is an imbalance in sphingolipid metabolism in psoriatic skin lesions. KXJD may reduce psoriasis-like lesions in mice by regulating sphingolipid metabolism via the SPHK2/S1P/MCP-1 pathway.

ObjectiveTo explore the effects of Kaixuan Jiedu core prescription （KXJD） on sphingolipid metabolism in the mouse model of imiquimod-induced psoriasis-like skin lesions. MethodsThirty-seven male C57BL/6J mice were randomly assigned into five groups： healthy control （n=11）， model （n=11）， methotrexate （MTX， n=5）， low-dose （15.21 g·kg^-1） KXJD （n=5）， and high-dose （30.42 g·kg^-1） KXJD （n=5）. Psoriasis-like skin lesions were induced in mice with 62.5 mg 5% imiquimod cream applied on the back. The KXJD groups and MTX group were treated with 0.2 mL corresponding decoction and MTX， respectively， by gavage daily， while the other groups were given an equal volume of normal saline by the same way. After 5 days of treatment， back skin lesions were collected. Firstly， healthy control and model mice were selected for tandem mass tag （TMT） quantitative proteomics （control vs model=3 vs 3） and targeted lipid metabolomics （control vs model=11 vs 11）. Then， the binding degree between core components and target proteins was predicted via network pharmacology and molecular docking. Finally， an animal experiment was performed to decipher the specific regulation mechanism of KXJD on sphingolipid metabolism. Immunohistochemistry was employed to determine the expression level of sphingosine-1-phosphate （S1P）， and Western blot was employed to determine the expression levels of sphingosine kinase 2 （SPHK2） and monocyte chemotactic protein-1 （MCP-1）. ResultsTMT proteomics and targeted lipid metabolomics suggested that sphingolipid metabolism was active in the psoriatic skin， and key proteases ［serine palmitoyltransferase， long chain base subunit 2 （SPTLC2）， SPHK2， delta（4）-desaturase sphingolipid 1 （Degs1）， and ceramide synthase 4 （CerS4）］ and 8 sphingolipid metabolites （including ceramides， sphingol， sphingomyelin， and glycosphingolipid） expressed abnormally （P<0.05） compared with those in the healthy skin. The molecular docking results indicated that the binding energy between the active components （quercetin， kaempferol， and luteolin） in KXJD and key proteins involved in sphingolipid metabolism was less than-8 kal·mol^-1. Further experimental verification showed elevated expression levels of SPHK2， S1P， and MCP-1 in psoriatic skin compared with healthy skin （P<0.05）， and KXJD down-regulated the expression levels of SPHK2， S1P， and MCP-1 compared with the model group （P<0.05）. ConclusionThis study indicates that there is an imbalance in sphingolipid metabolism in psoriatic skin lesions. KXJD may reduce psoriasis-like lesions in mice by regulating sphingolipid metabolism via the SPHK2/S1P/MCP-1 pathway.

Objective To investigatethe relationship between gastroesophageal reflux disease (GERD) symptoms and clinicopathological characteristics, p53 expression, and survival of Chinese patients with esophageal adenocarcinoma. Methods A total of 3882 patients with esophageal adenocarcinoma, 970 matched patients with esophageal squamous cell carcinoma, and 970 matched patients with gastric cardia adenocarcinoma were included to compare the incidence of GERD symptoms. Patients with esophageal adenocarcinoma were divided into two groups according to the presence and absence of GERD symptoms. The differences in clinicopathological characteristics and p53 expression between the two groups were compared by chi-square test, and the differences in survival between the two groups were compared by landmark analysis. Results The incidence of GERD symptoms increased successively in esophageal squamous cell carcinoma, esophageal adenocarcinoma, and gastric cardia adenocarcinoma. In patients with esophageal adenocarcinoma, the proportions of male, less than 65 years old, lower thoracic tumors, tumors without squamous cell carcinoma, poorly differentiation, early tumors (stage 0-I), and p53-positive tumors in the group with GERD symptoms were higher than those in the group without GERD symptoms; moreover, the long-term survival (≥15 years) was better. Conclusion GERD symptom is an important clinical sign of esophageal adenocarcinoma. It is closely related to specific clinicopathological characteristics, p53 overexpression, and good long-term prognosis.

ObjectiveTo screen and evaluate the antidepressant compounds of Curcumae Rhizoma， and explore its mechanism of regulating the nuclear factor erythroid 2-related factor 2（Nrf2）/glutathione（GSH） peroxidase 4（GPX4）/GSH pathway from an antioxidant perspective. MethodsThe antioxidant activities in vitro of 11 characteristic components from Curcumae Rhizoma， including curcumol， curgerenone， curdione， curzerene， curcumenol， curcumenone， dehydrocurdione， isocurcumenol， furanodienone， furanodiene and zederone， were detected using 1，1-diphenyl-2-picrylhydrazyl（DPPH） and 2，2'-azinobis-（3-ethylbenzothiazoline-6-sulphonic acid） diammonium salt（ABTS） radical scavenging assays. The depression in Drosophila melanogaster was induced by chronic unpredictable mild stress（CUMS）， and W1118 wild-type male D. melanogaster were randomly divided into blank group， model group， curcumol group， curgerenone group， curdione group， curzerene group， curcumenol group，curcumenone group， dehydrocurdione group， isocurcumenol group， furanodienone group， furanodiene group， zederone group and fluoxetine group（10 μmol·L^-1）. The treatment groups received a dose of 0.1 g·L^-1 of 11 characteristic components from Curcumae Rhizoma， while the blank and model groups were administered equivalent volumes of solvent. The sucrose preference test， climbing test and forced swimming test were used to evaluate the behavioral indicators of depression in D. melanogaster. Liquid chromatography-mass spectrometry（LC-MS） was used to detect the levels of 5-hydroxytryptamine（5-HT） and dopamine（DA） in the brain of D. melanogaster， and the entropy weight method was used to comprehensively evaluate neurobehavioral and neurotransmitter indicators， resulting in the identification of the antidepressant active components of Curcumae Rhizoma. In addition， a mouse depression model was established by CUMS， and C57BL/6J mice were randomly divided into blank group， model group， low and high dose groups of curzerene（0.5， 1 mg·kg^-1）， and fluoxetine group（10 mg·kg^-1） to confirm the antidepressant effect of the optimal active ingredient by behavioral analysis. Flow cytometry was used to detect the content of reactive oxygen species（ROS） in the hippocampus of mice from each group. Enzyme-linked immunosorbent assay was used to detect the contents of adenosine triphosphate（ATP）， superoxide dismutase（SOD）， catalase（CAT） and GSH. Transmission electron microscope（TEM） was used to observe the effect of curzerene on the ultrastructure of mitochondria in hippocampal tissue. Western blot was performed to determine the level of Nrf2 protein， and Nrf2 inhibitor（ML385） was used to verify the relationship between the antidepressant effect of curzerene and regulation of Nrf2. Real time fluorescence quantitative polymerase chain reaction（Real-time PCR） was employed to detect the effect of curzerene on the mRNA expression level of GPX. ResultsIn vitro antioxidant experiments showed that curzerene and curgerenone exhibited the most significant ability to scavenge free radicals， and comprehensive evaluation results of entropy weight method indicated that curzerene stood out as the most promising active component. Compared with the blank group， the model group exhibited a significant decrease in sucrose preference coefficient and the number of times entering the open field center（P<0.01）， as well as a significant increase in immobility time in the forced swimming and tail suspension tests（P<0.01）， and the ROS content in hippocampus significantly elevated（P<0.01）， while the ATP content significantly reduced（P<0.01）. In the hippocampal neurons of the model group， mitochondrial cristae were disordered， with vacuolation of the inner membrane and severe damage. Nrf2 protein expression level in the model group was significantly decreased（P<0.05）， and the antioxidant enzymes SOD， CAT and GSH contents were also significantly reduced（P<0.05， P<0.01）， and the gene expression levels of GPX1， GPX4 and GPX7 were significantly decreased（P<0.01）. Compared with the model group， the high-dose group of curzerene showed a significant increase in the sucrose preference coefficient and the number of times entering the open field center（P<0.05）， as well as a significant decrease in immobility time in the forced swimming and tail suspension tests（P<0.05， P<0.01）. The ROS content in the hippocampus of the high-dose group of curzerene was significantly reduced（P<0.01）， while the ATP content was significantly increased（P<0.05）. The neuronal mitochondrial damage in the hippocampus of the high-dose group of curzerene was alleviated， and the expression level of Nrf2 protein was significantly increased（P<0.05）. The Nrf2 inhibitor ML385 reversed the improvement of curzerene on depressive behaviors in CUMS mice. The GSH content in the hippocampal neurons of the high-dose group of curzerene was significantly increased（P<0.01）， while there were no significant differences in SOD and CAT contents. The expression level of GPX4 gene in the hippocampal neurons of the high-dose group of curzerene was significantly increased（P<0.05）， while there were no significant differences in other GPX genes. ConclusionCurzerene is the best component with antidepressant activity in Curcumae Rhizoma. It may improve mitochondrial dysfunction to exert its antidepressant effect by regulating Nrf2 and its downstream GPX4/GSH pathway rather than CAT or SOD pathways.

ObjectiveTo investigate the effects of different fermentation methods and times on the fungal flora and chemical composition of Aurantii Fructus， in order to obtain the optimal fermentation conditions and flora structure， and to ensure the stability and controllability of the fermented varieties. MethodsScanning electron microscopy was used to observe and analyze the colony characteristics on the surface of Aurantii Fructus under different fermentation conditions. Internal transcribed spacer 2（ITS2） high-throughput sequencing， combined with fungal community diversity analysis and fungal community structure analysis， were used to obtain the fungal flora microbial categories of Aurantii Fructus under the conditions of traditional pressure-shelf fermentation and non-pressure-shelf natural fermentation for 7， 14， 21 d（numbered Y1-Y3 for the former， and numbered F1-F3 for the latter）， respectively. At the same time， the chemical components in the fermentation process were detected by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS/MS）， combined with principal component analysis（PCA）， partial least squares-discriminant analysis（PLS-DA） and compound retention time， parent ions， characteristic fragment ions and other information， the differential compounds between the different fermentation samples were screened and identified. ResultsThe analysis of fungal community diversity showed that the dominant flora did not change at different fermentation time points in the traditional pressure-shelf fermentation method， while in the non-pressure-shelf natural fermentation method， there was a significant difference with the fermentation process， and at the genus level， the dominant genus of samples Y1， Y2， Y3 and F2 was Aspergillus， while the dominant genera of samples F1 and F3 were both Rhizopus. This indicated that the microbial growth environment provided by the traditional fermentation method was more stable， and the microbial community structure was more stable， which was more conducive to the stable and controllable fermentation process and fermented products. A total of 155 compounds were identified by compositional analysis， including 70 flavonoids， 38 coumarins， 10 alkaloids， 34 organic acids and 3 other compounds. After fermentation， two new components of ribalinine and pranferin were produced. Different fermentation conditions also brought about differences in chemical composition， multivariate statistical analysis obtained 26 differential compounds under two different fermentation methods， mainly including flavonoids， organic acids and coumarins. Comprehensively， the microbial community structure of samples fermented by the traditional pressure-shelf method of Aurantii Fructus for 14 d was stable， the species richness was high and the overall content of differential compounds was high， which was the optimal processing condition. ConclusionCompared with non-pressure-shelf natural fermentation， the traditional method has obvious advantages in terms of the stability of the microbial community structure and the content of chemical compounds， and the optimal condition is 14 days of fermentation. This study is helpful to promote the quality stability and fermentation bioavailability of fermented products of Aurantii Fructus， as well as to provide an experimental basis for the further improvement of the quality control methods of this variety.

ObjectiveTo investigate the effects of different fermentation methods and times on the fungal flora and chemical composition of Aurantii Fructus， in order to obtain the optimal fermentation conditions and flora structure， and to ensure the stability and controllability of the fermented varieties. MethodsScanning electron microscopy was used to observe and analyze the colony characteristics on the surface of Aurantii Fructus under different fermentation conditions. Internal transcribed spacer 2（ITS2） high-throughput sequencing， combined with fungal community diversity analysis and fungal community structure analysis， were used to obtain the fungal flora microbial categories of Aurantii Fructus under the conditions of traditional pressure-shelf fermentation and non-pressure-shelf natural fermentation for 7， 14， 21 d（numbered Y1-Y3 for the former， and numbered F1-F3 for the latter）， respectively. At the same time， the chemical components in the fermentation process were detected by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS/MS）， combined with principal component analysis（PCA）， partial least squares-discriminant analysis（PLS-DA） and compound retention time， parent ions， characteristic fragment ions and other information， the differential compounds between the different fermentation samples were screened and identified. ResultsThe analysis of fungal community diversity showed that the dominant flora did not change at different fermentation time points in the traditional pressure-shelf fermentation method， while in the non-pressure-shelf natural fermentation method， there was a significant difference with the fermentation process， and at the genus level， the dominant genus of samples Y1， Y2， Y3 and F2 was Aspergillus， while the dominant genera of samples F1 and F3 were both Rhizopus. This indicated that the microbial growth environment provided by the traditional fermentation method was more stable， and the microbial community structure was more stable， which was more conducive to the stable and controllable fermentation process and fermented products. A total of 155 compounds were identified by compositional analysis， including 70 flavonoids， 38 coumarins， 10 alkaloids， 34 organic acids and 3 other compounds. After fermentation， two new components of ribalinine and pranferin were produced. Different fermentation conditions also brought about differences in chemical composition， multivariate statistical analysis obtained 26 differential compounds under two different fermentation methods， mainly including flavonoids， organic acids and coumarins. Comprehensively， the microbial community structure of samples fermented by the traditional pressure-shelf method of Aurantii Fructus for 14 d was stable， the species richness was high and the overall content of differential compounds was high， which was the optimal processing condition. ConclusionCompared with non-pressure-shelf natural fermentation， the traditional method has obvious advantages in terms of the stability of the microbial community structure and the content of chemical compounds， and the optimal condition is 14 days of fermentation. This study is helpful to promote the quality stability and fermentation bioavailability of fermented products of Aurantii Fructus， as well as to provide an experimental basis for the further improvement of the quality control methods of this variety.

Objective To investigate the changes in eosinophil counts and the activation of microglial cells in the brain tissues of mice at different stages of Angiostrongylus cantonensis infection, and to examine the role of microglia in regulating the progression of angiostrongyliasis and unravel the possible molecular mechanisms. Methods Fifty BALB/c mice were randomly divided into the control group and the 7-d, 14-d, 21-day and 25-d infection groups, of 10 mice in each group. All mice in infection groups were infected with 30 stage III A. cantonensis larvae by gavage, and animals in the control group was given an equal amount of physiological saline. Five mice were collected from each of infection groups on days 7, 14, 21 d and 25 d post-infection, and 5 mice were collected from the control group on the day of oral gavage. The general and focal functional impairment was scored using the Clark scoring method to assess the degree of mouse neurological impairment. Five mice from each of infection groups were sacrificed on days 7, 14, 21 d and 25 d post-infection, and 5 mice from the control group were sacrificed on the day of oral gavage. Mouse brain tissues were sampled, and the pathological changes of brain tissues were dynamically observed using hematoxylin and eosin (HE) staining. Immunofluorescence staining with eosinophilic cationic protein (ECP) and ionized calcium binding adaptor molecule 1 (Iba1) was used to assess the degree of eosinophil infiltration and the counts of microglial cells in mouse brain tissues in each group, and the morphological parameters of microglial cells (skeleton analysis and fractal analysis) were quantified by using Image J software to determine the morphological changes of microglial cells. In addition, the expression of M1 microglia markers Fcγ receptor III (Fcgr3), Fcγ receptor IIb (Fcgr2b) and CD86 antigen (Cd86), M2 microglia markers Arginase 1 (Arg1), macrophage mannose receptor C-type 1 (Mrc1), chitinase-like 3 (Chil3), and phagocytosis genes myeloid cell triggering receptor expressed on myeloid cells 2 (Trem2), CD68 antigen (Cd68), and apolipoprotein E (Apoe) was quantified using real-time quantitative reverse transcription PCR (RT-qPCR) assay in the mouse cerebral cortex of mice post-infection. Results A large number of A. cantonensis larvae were seen on the mouse meninges surface post-infection, and many neuronal nuclei were crumpled and deeply stained, with a large number of bleeding points in the meninges. The median Clark scores of mouse general functional impairment were 0 (interquartile range, 0), 0 (interquartile range, 0.5), 6 (interquartile range, 1.0), 14 (interquartile range, 8.5) points and 20 (interquartile range, 9.0) points in the control group and the 7-d, 14-d, 21-d and 25-d groups, respectively (H = 22.45, P < 0.01), and the median Clark scores of mouse focal functional impairment were 0 (interquartile range, 0), 2 (interquartile range, 2.5), 7 (interquartile range, 3.0), 18 (interquartile range, 5.0) points and 25 (interquartile range, 6.5) points in the control group and the 7-d, 14-d, 21-d and 25-d groups, respectively (H = 22.72, P < 0.01). The mean scores of mice general and focal functional impairment were all higher in the infection groups than in the control group (all P values < 0.05). Immunofluorescence staining showed a significant difference in the eosinophil counts in mouse brain tissues among the five groups (F = 40.05, P < 0.000 1), and the eosinophil counts were significantly higher in mouse brain tissues in the 14-d (3.08 ± 0.78) and 21-d infection groups (5.97 ± 1.37) than in the control group (1.00 ± 0.28) (both P values < 0.05). Semi-quantitative analysis of microglia immunofluorescence showed a significant difference in the counts of microglial cells among the five groups (F = 17.66, P < 0.000 1), and higher Iba1 levels were detected in mouse brain tissues in 14-d (5.75 ± 1.28), 21-d (6.23 ± 1.89) and 25-d infection groups (3.70 ± 1.30) than in the control group (1.00 ± 0.30) (all P values < 0.05). Skeleton and fractal analyses showed that the branch length [(162.04 ± 34.10) μm vs. (395.37 ± 64.11) μm; t = 5.566, P < 0.05] and fractal dimension of microglial cells (1.30 ± 0.01 vs. 1.41 ± 0.03; t = 5.266, P < 0.05) were reduced in mouse brain tissues in the 21-d infection group relative to the control group. In addition, there were significant differences among the 5 groups in terms of M1 and M2 microglia markers Fcgr3 (F = 48.34, P < 0.05), Fcgr2b (F = 55.46, P < 0.05), Cd86 (F = 24.44, P < 0.05), Arg1 (F = 31.18, P < 0.05), Mrc1 (F = 15.42, P < 0.05) and Chil3 (F = 24.41, P < 0.05), as well as phagocytosis markers Trem2 (F = 21.19, P < 0.05), Cd68 (F = 43.95, P < 0.05) and Apoe (F = 7.12, P < 0.05) in mice brain tissues. Conclusions A. cantonensis infections may induce severe pathological injuries in mouse brain tissues that are characterized by massive eosinophil infiltration and persistent activation of microglia cells, thereby resulting in progressive deterioration of neurological functions.

[This corrects the article DOI: 10.1016/j.apsb.2022.06.016.].

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.

ObjectiveTo conduct comprehensive assessment of internal and external cadmium exposure and health risks for Shanghai residents. MethodsCadmium levels in food samples were calculated by employing two dietary exposure assessment methods， total diet study （TDS） and food frequency questionnaire （FFQ）， to estimate the daily dietary cadmium exposure of Shanghai residents. The provisional tolerable monthly intake （PTMI） of cadmium set by joint food and agriculture organization/WHO expert committee on food additives （JECFA） was applied to evaluate the health risk. Differences in dietary and urinary cadmium were compared by rank-sum test among different regions， age， gender， smoking status， and BMI groups， and the association between internal and external cadmium exposure was investigated by correlation analysis. ResultsThe mean value of urinary cadmium for 1 300 respondents was 0.542 μg·L^-1. Urinary cadmium was higher in the population in central urban and urban-rural fringe areas than in the suburban area， higher in the older age group than in the younger age group， and higher in the smoking group than in the non-smoking group （all P<0.01）. The two assessment methods showed that the mean values of daily dietary cadmium exposure for Shanghai residents were 0.306 and 0.090 μg·kg^-1， with 3.69% and 0.85% of Shanghai residents exceeding the PTMI， respectively. Correlation analyses showed that dietary exposure to cadmium based on the FFQ method was positively correlated with the urinary cadmium level when smoking status， age， gender， and BMI were adjusted. ConclusionDietary exposure to cadmium of Shanghai residents is mainly derived from vegetables， aquatic products， cereals and potatoes， and is overall at a low-risk level. Dietary exposure assessment based on FFQ and risk monitoring data can effectively estimate long-term cadmium exposure.