Objective To evaluate the transition rules of normal body mass index(BMI),overweight and metabolic syndrome(MetS)in patients with major depressive disorder(MDD).Methods Patients with MDD who had multiple admission records between Jan 2016 and Nov 2021 in Beijing Anding Hospital,Capital Medical University were included.Based on the overweight and metabolic syndrome status assessed at each admission,the patients were categorized into three states:normal BMI,overweight and metabolic syndrome.A multi-state Markov model was used to analyze the transition intensity and transition frequency between three states and the influence of covariates on transitions.Results A total of 892 records of 398 subjects were included,with a median age of 56 years old and 31.4% males.The median follow-up period was 40 months.The multi-state model showed that there were 494 transitions between the three states,of which 5.1% moved from normal BMI to overweight and 5.5% moved from overweight to MetS.The intensity of transition was the highest from overweight to MetS,9.52 times greater than overweight to normal BMI.After 48.53 months,MDD patients with normal BMI began to transition to MetS.For overweight MDD patients,the transition to MetS started after 8.77 months.MDD patients with normal BMI or overweight had 31.4% and 50.4% probabilities of developing Mets after 36 months.For MDD patients comorbid with MetS,the probability of staying at MetS was 51.2% after 36 months.Multivariate analysis showed that being unmarried was a risk factor against developing overweight in normal BMI MDD patients,while a higher level of education was a protective factor against developing MetS in overweight MDD patients.Conclusion MDD patients exhibited a higher intensity and risk of developing MetS,and it is not easy to reverse MetS,suggesting that BMI management and MetS intervention should be strengthened in MDD patients.

ObjectiveTo analyze the characteristic expression patterns of six neurotransmitters including 5-hydroxytryptamine （5-HT）， dopamine （DA）， acetylcholine （ACh）， norepinephrine （NE）， inhibitory neurotransmitter （INH）， and excitatory neurotransmitter （EXC） in the whole brain and different brain regions of depression patients by Search of Encephalo Telex （SET）， providing new ideas for the study of heterogeneous etiology of depression. Methods（1） A retrospective study was conducted on supra-slow signals of EEG fluctuations in 1 028 patients with depression. The SET system was used to obtain the expression information of six neurotransmitters in the whole brain and 12 brain regions： left frontal region （F3）， right frontal region （F4）， left central region （C3）， right central region （C4）， left parietal region （P3）， right parietal region （P4）， left occipital region （O1）， right occipital region （O2）， left anterior temporal region （F7）， right anterior temporal region （F8）， left posterior temporal region （T5）， and right posterior temporal region （T6）. The expression information of each neurotransmitter was compared with the normal model， and it was found that single neurotransmitter was in one of three states： increased， decreased， or normal expression. The simultaneous expression states of six neurotransmitters in the brain space were referred to as the expression pattern of multiple neurotransmitters. （2） A MySQL database was established to analyze the actual expression patterns of different neurotransmitters in the whole brain of patients with depression. （3） Factor analysis was conducted to further analyze the characteristic rules of 78 variables of neurotransmitters in the whole brain and 12 brain regions in depression patients. Results（1） The expression of single neurotransmitters in the whole brain and different brain regions of the total depression population showed one of three expression states （increased/decreased/normal）， being normal in the majority. The decreased and increased expression of 5-HT， ACh， DA， INH， EXC， and NE in the whole brain occurred in 6% and 25%， 31% and 17%， 36% and 9%， 15% and 31%， 32% and 14%， and 22% and 22%， respectively. （2） The antagonizing pairs of neurotransmitters （EXC/INH， DA/5-HT， and ACh/NE） showed significant antagonistic relationships in the whole brain and different brain regions， with a strong negative correlation between EXC and INH （P<0.01， |r| values ranging from 0.69 to 0.76）， a strong negative correlation between DA and 5-HT （P<0.01， |r| values ranging from 0.83 to 0.90）， and a moderate negative correlation between ACh and NE （P<0.01， with |r| values ranging from 0.56 to 0.66）. Meanwhile， non-antagonizing pairs of neurotransmitters in the whole brain and different brain regions also showed correlations， with DA/NE （P<0.01， |r| values ranging from 0.38 to 0.46） and NE/EXC （P<0.01， |r| values ranging from 0.56 to 0.61） showing weak and moderate negative correlations， respectively， and DA/EXC showing a weak positive correlation （P<0.01， |r| values ranging from 0.38 to 0.47）. （3） The six neurotransmitters in the 1 028 patients with depression presented a total of 170 expression patterns in the whole brain. The top 30 expression patterns were reported in this paper， with a cumulative rate of 60.60%， including patterns ① INH+/5-HT-/ACh+/DA+/NE-/EXC- （9.05%）， ② INH+/5-HT-/ACh↓/DA+/NE-/EXC- （4.57%）， and ③ INH+/5-HT-/ACh+/DA+/NE↓/EXC- （3.31%）. That is， the proportion of depression patients with normal levels of all the six neurotransmitters was 9.05%， and the patients with at least one neurotransmitter abnormality accounted for 91.95%. （4） The factor analysis extracted 22 common factors from 78 variables in the whole brain and different brain regions. These common factors showed the absolute values of loadings ranging from 0.32 to 0.86 and the eigenvalues （F） ranging from 1.03 to 13.43， with a cumulative contribution rate of 76.82%. The characteristic expression patterns included ① ACh_P3↓/ACh_W↓/ACh_C3↓/ACh_F3↓/ACh_O1↓/ACh_T5↓/ACh_F7↓/NE_P3↑/NE_W↑/NE_C3↑/NE_F3↑/NE_O1↑/NE_T5↑/NE_F7↑ （F=13.43， whole brain）， ② 5-HT_O2↑/DA_O2↓/5-HT_P4↑/DA_P4↓/5-HT_W↑/DA_W↓/5-HT_C4↑/DA_C4↓ （F=5.94）， and ③ EXC_F4↓/DA_F4↓/NE_F4↑/INH_F4↑/5-HT_F4↑/ACh_F4↓ （F=5.33）. ConclusionThe actual 170 expression patterns of 6 neurotransmitters in the whole brain of 1 028 depression patients indicate that depression is a heterogeneous disease with individualized characteristics. The 22 characteristic expression patterns in the whole brain and 12 brain regions verify the pathogenesis hypothesis of multi-neurotransmitters oscillation imbalance in brains of depression patients. In summary， this study provides new guidance for the etiology， diagnosis， and treatment of depression and establishes a methodological foundation for the effectiveness evaluation of individualized treatment of depression by traditional Chinese medicine based on the objective biological markers.

ObjectiveTo analyze the characteristic expression patterns of six neurotransmitters including 5-hydroxytryptamine （5-HT）， dopamine （DA）， acetylcholine （ACh）， norepinephrine （NE）， inhibitory neurotransmitter （INH）， and excitatory neurotransmitter （EXC） in the whole brain and different brain regions of depression patients by Search of Encephalo Telex （SET）， providing new ideas for the study of heterogeneous etiology of depression. Methods（1） A retrospective study was conducted on supra-slow signals of EEG fluctuations in 1 028 patients with depression. The SET system was used to obtain the expression information of six neurotransmitters in the whole brain and 12 brain regions： left frontal region （F3）， right frontal region （F4）， left central region （C3）， right central region （C4）， left parietal region （P3）， right parietal region （P4）， left occipital region （O1）， right occipital region （O2）， left anterior temporal region （F7）， right anterior temporal region （F8）， left posterior temporal region （T5）， and right posterior temporal region （T6）. The expression information of each neurotransmitter was compared with the normal model， and it was found that single neurotransmitter was in one of three states： increased， decreased， or normal expression. The simultaneous expression states of six neurotransmitters in the brain space were referred to as the expression pattern of multiple neurotransmitters. （2） A MySQL database was established to analyze the actual expression patterns of different neurotransmitters in the whole brain of patients with depression. （3） Factor analysis was conducted to further analyze the characteristic rules of 78 variables of neurotransmitters in the whole brain and 12 brain regions in depression patients. Results（1） The expression of single neurotransmitters in the whole brain and different brain regions of the total depression population showed one of three expression states （increased/decreased/normal）， being normal in the majority. The decreased and increased expression of 5-HT， ACh， DA， INH， EXC， and NE in the whole brain occurred in 6% and 25%， 31% and 17%， 36% and 9%， 15% and 31%， 32% and 14%， and 22% and 22%， respectively. （2） The antagonizing pairs of neurotransmitters （EXC/INH， DA/5-HT， and ACh/NE） showed significant antagonistic relationships in the whole brain and different brain regions， with a strong negative correlation between EXC and INH （P<0.01， |r| values ranging from 0.69 to 0.76）， a strong negative correlation between DA and 5-HT （P<0.01， |r| values ranging from 0.83 to 0.90）， and a moderate negative correlation between ACh and NE （P<0.01， with |r| values ranging from 0.56 to 0.66）. Meanwhile， non-antagonizing pairs of neurotransmitters in the whole brain and different brain regions also showed correlations， with DA/NE （P<0.01， |r| values ranging from 0.38 to 0.46） and NE/EXC （P<0.01， |r| values ranging from 0.56 to 0.61） showing weak and moderate negative correlations， respectively， and DA/EXC showing a weak positive correlation （P<0.01， |r| values ranging from 0.38 to 0.47）. （3） The six neurotransmitters in the 1 028 patients with depression presented a total of 170 expression patterns in the whole brain. The top 30 expression patterns were reported in this paper， with a cumulative rate of 60.60%， including patterns ① INH+/5-HT-/ACh+/DA+/NE-/EXC- （9.05%）， ② INH+/5-HT-/ACh↓/DA+/NE-/EXC- （4.57%）， and ③ INH+/5-HT-/ACh+/DA+/NE↓/EXC- （3.31%）. That is， the proportion of depression patients with normal levels of all the six neurotransmitters was 9.05%， and the patients with at least one neurotransmitter abnormality accounted for 91.95%. （4） The factor analysis extracted 22 common factors from 78 variables in the whole brain and different brain regions. These common factors showed the absolute values of loadings ranging from 0.32 to 0.86 and the eigenvalues （F） ranging from 1.03 to 13.43， with a cumulative contribution rate of 76.82%. The characteristic expression patterns included ① ACh_P3↓/ACh_W↓/ACh_C3↓/ACh_F3↓/ACh_O1↓/ACh_T5↓/ACh_F7↓/NE_P3↑/NE_W↑/NE_C3↑/NE_F3↑/NE_O1↑/NE_T5↑/NE_F7↑ （F=13.43， whole brain）， ② 5-HT_O2↑/DA_O2↓/5-HT_P4↑/DA_P4↓/5-HT_W↑/DA_W↓/5-HT_C4↑/DA_C4↓ （F=5.94）， and ③ EXC_F4↓/DA_F4↓/NE_F4↑/INH_F4↑/5-HT_F4↑/ACh_F4↓ （F=5.33）. ConclusionThe actual 170 expression patterns of 6 neurotransmitters in the whole brain of 1 028 depression patients indicate that depression is a heterogeneous disease with individualized characteristics. The 22 characteristic expression patterns in the whole brain and 12 brain regions verify the pathogenesis hypothesis of multi-neurotransmitters oscillation imbalance in brains of depression patients. In summary， this study provides new guidance for the etiology， diagnosis， and treatment of depression and establishes a methodological foundation for the effectiveness evaluation of individualized treatment of depression by traditional Chinese medicine based on the objective biological markers.

Objective To evaluate the transition rules of normal body mass index(BMI),overweight and metabolic syndrome(MetS)in patients with major depressive disorder(MDD).Methods Patients with MDD who had multiple admission records between Jan 2016 and Nov 2021 in Beijing Anding Hospital,Capital Medical University were included.Based on the overweight and metabolic syndrome status assessed at each admission,the patients were categorized into three states:normal BMI,overweight and metabolic syndrome.A multi-state Markov model was used to analyze the transition intensity and transition frequency between three states and the influence of covariates on transitions.Results A total of 892 records of 398 subjects were included,with a median age of 56 years old and 31.4% males.The median follow-up period was 40 months.The multi-state model showed that there were 494 transitions between the three states,of which 5.1% moved from normal BMI to overweight and 5.5% moved from overweight to MetS.The intensity of transition was the highest from overweight to MetS,9.52 times greater than overweight to normal BMI.After 48.53 months,MDD patients with normal BMI began to transition to MetS.For overweight MDD patients,the transition to MetS started after 8.77 months.MDD patients with normal BMI or overweight had 31.4% and 50.4% probabilities of developing Mets after 36 months.For MDD patients comorbid with MetS,the probability of staying at MetS was 51.2% after 36 months.Multivariate analysis showed that being unmarried was a risk factor against developing overweight in normal BMI MDD patients,while a higher level of education was a protective factor against developing MetS in overweight MDD patients.Conclusion MDD patients exhibited a higher intensity and risk of developing MetS,and it is not easy to reverse MetS,suggesting that BMI management and MetS intervention should be strengthened in MDD patients.

Objective:To investigate the concern about pollen broadcasting in Chinese population from multiple dimensions and to understand the information about allergic rhinitis (AR) in China by analyzing related factors.Methods:From March 1 to September 30, 2022, a large-scale multi-center cross-sectional survey was conducted based on the Questionnaire Star platform in 21 Chinese hospitals. A total of 7 056 subjects from 7 regions in China: Northeast, North, East, Central, South, Southwest, and Northwest China were included. Basic characteristics (including social demographic characteristics and disease characteristics of AR patients), concern about pollen broadcasting, the willingness of pollen-induced AR (PiAR) patients to receive pollen broadcasting, and the treatment satisfaction rate of AR patients were collected. The chi-square test, multivariate linear regression model, and Logistic regression analysis were used to analyze the concern about pollen broadcasting in the Chinese population and related factors from multiple dimensions.Results:Among 7 056 subjects, 23.02% were concerned about pollen broadcasting. Among 3 176 self-reported AR and 1 019 PiAR patients, 25.60% and 39.16% were concerned about pollen broadcasting, respectively, which was higher than that of non-AR or non-PiAR subjects ( χ2 value was 21.74 and 175.11, respectively, both P<0.001). Among AR patients, the proportion of spring and autumn allergen-positive patients concerned about pollen broadcasting was higher than that in perennial allergen-positive patients ( χ2 value was 20.90 and 19.51, respectively, both P<0.001). The proportion of AR patients with asthma, sinusitis, allergic conjunctivitis, and cardiovascular and cerebrovascular diseases was higher than those without complications ( χ2 value was 50.83, 21.97, 56.78, 7.62, respectively, all P<0.05). The proportion of AR patients in North China who could find pollen broadcasting locally was 31.01%, significantly higher than those in other regions (all P<0.05). Multivariate linear regression model analysis showed that among PiAR patients, those with higher per capita household income and higher AR disease cognition levels had been concerned about pollen broadcasting in the past, and those complicated with allergic conjunctivitis had stronger intention to receive pollen broadcasting (B value was 0.24, 0.13, 0.66, 0.47, respectively, all P<0.05). The higher the disease cognition level of PiAR patients, the stronger their willingness to actively participate in treatment ( R2=0.72, P<0.001). Only 18.89% of AR patients felt satisfied with the treatment effect. Logistic regression analysis showed that in AR patients, the treatment satisfaction rate was significantly higher among those concerned about pollen broadcasting compared to those who were not ( OR=1.83, P<0.001). Conclusions:Currently, the dissemination of pollen broadcasting in China is hindered by various factors such as disease cognition level. The treatment satisfaction among AR patients remains unsatisfactory.

ObjectiveTo investigate the intervention effect of heat shock protein 60 (HSP60) on learning and memory impairment induced by combined exposure to lead and hypertension in mice, and the relative mechanism of triggering receptor expressed on myeloid cells 2 (TREM2). Methods Specific pathogen-free C57BL/6J male mice were randomly divided into control group, hypertension group, lead-exposed group and lead-exposed + hypertension group, or into control group, heat shock protein 60 (HSP60) control group, lead-exposed + hypertension group and HSP60 intervention group, with 10 mice in each group. Mice of hypertension group and lead-exposed + hypertension group were intraperitoneally injected with angiotensin Ⅱ at a dose of 0.5 mg/(kg·d) for seven consecutive days to induce hypertension model. Mice of the lead-exposed group, lead-exposed + hypertension group, and HSP60 intervention group were given lead acetate drinking water with a mass concentration of 250.0 mg/L, while mice in the control group, hypertension group, and HSP60 control group were given purified water for 12 weeks. Mice of the HSP60 control group and HSP60 intervention group were intraperitoneally injected with a solution of HSP60 at a dose of 4 mg/kg body weight, every other day for a total of three times at the 12th week. The learning and memory ability of mice was detected using the Morris water maze test. The enzyme-linked immunosorbent assay was used to detect the levels of interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α) in the hippocampal tissues of the mice. The relative expression of ionized calcium binding adaptor molecule-1 (IBA1) and TREM2 protein in the hippocampus of mice was detected using Western blot. Results i) The number of platform crossings of the mice in the hypertension group and the lead-exposed group was lower than that in the control group (both P<0.05). The escape latency of the mice on the third day was longer and the number of platform crossings was lower in the lead-exposed + hypertension group compared with the control group, hypertension group and lead-exposed group (all P<0.05). The levels of IL-1β, IL-6, and TNF-α in the hippocampus of the other three groups increased compared with the control group (all P<0.05). The relative expression of IBA1 protein in the hippocampus of lead-exposed group and lead-exposed + hypertension group increased (all P<0.05), while the relative protein expression of TREM2 decreased compared with the control group (all P<0.05). The levels of IL-1β, IL-6, TNF-α, and the relative protein expression of IBA1 protein in the hippocampus of the lead-exposed+hypertension group were higher (all P<0.05), and relative expression of TREM2 protein was lower (P<0.05) than those in the hypertension group. The level of TNF-α and the relative expression of IBA1 protein in the hippocampus of lead-exposed+hypertension group were higher than those in lead-exposed group (all P<0.05). ii) The escape latency of mice in the lead-exposed + hypertension group was longer than that in the control group (P<0.05), and the number of platform crossings was fewer than that in the control group (P<0.05). The escape latency of mice in the HSP60 intervention group was shortened (P<0.05), the number of platform crossings increased (P<0.05), and the levels of IL-1β, IL-6, TNF-α and relative expression of IBA1 protein decreased in the hippocampus (all P<0.05), while the relative expression of TREM2 protein increased (P<0.05) compared with the lead-exposed+hypertension group. Conclusion Combined exposure of lead and hypertension has a synergistic effect on learning and memory impairment in mice. The mechanism may be related to the inhibition of TREM2 expression by lead in the hippocampus of hypertensive mice and aggravating the neuroinflammatory response. Intervention with TREM2 receptor agonist HSP60 can alleviate learning and memory impairment in mice exposed to lead and hypertension by up-regulating TREM2 expression in the hippocampus.

Objective To explore the etiology,types,treatment,and prognosis of new-onset epilep-sy in elderly dementia.Methods A retrospective analysis was conducted on 45 new-onset epilepsy in elderly dementia admitted to our department from January 2017 to December 2023.According to their etiology,they were divided into a degenerative dementia group(with AD as the main cause,AD dementia group,24 cases,)and a non-degenerative dementia group(non-AD dementia group,21 cases).Seizure types and and electroencephalogram(EEG)findings were compared be-tween the two groups.The medication and efficacy were also compared between the two groups in 3 months after treatment with antiepileptic drugs.Results Each patient had at least one type of seizure.The AD dementia group had a lower incidence of generalized seizure,but higher incidences of focal seizure and non-convulsive seizure(NCS)when compared with the non-AD dementia group(P＜0.05,P＜0.01).At least one type of abnormal EEG findings was observed in each pa-tient,but there was no statistical difference in the occurrence of EEG abnormalities between the two groups(P＞0.05).Among the 45 patients,42(93.3％)received antiepileptic drugs,and 38(90.5％)patients were well controlled,with the AD dementia group having a higher effective rate of single antiepileptic drug than the non-AD dementia group(95.5％vs 85.7％,P＜0.05).Conclu-sion Dementia combined with epilepsy(especially NCS)is often hard to detect,and continuous EEG monitoring is essential for elderly dementia patients.Most new-onset epilepsy in elderly de-mentia can be effectively controlled through antiepileptic drug therapy.

Objective: To investigate the effects of combined exposure to black carbon and lead on the expression of cell adhesion molecules and their regulating microRNAs (miRNAs) in the rat choroid plexus epithelial Z310 cells. Methods: i) Z310 cells were randomly divided into control group, black carbon exposure group, lead exposure group and combined exposure group. The lead exposure group and black carbon exposure group were treated with 10 μmol/L lead acetate and 10 mg/L black carbon, respectively, and the combined exposure group was treated with both in the above doses. After 12.0 hours, the expressions of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and mucosal vascular addressin cell adhesion molecule-1 (MAdCAM-1) in Z310 cells was detected by Western blotting. The expression of miR-326, miR-328-3p and miR-542-3p which regulated ICAM-1 was detected by real-time fluorescent quantitative polymerase chain reaction. ii) Z310 cells or Z310 cells transfected with miRNA-326 mimic were randomly divided into control group, miRNA-326 transfection control group, combined exposure group and miRNA-326 transfection combined exposure group. Cells in the two control groups were not treated. The two combined exposure groups were treated with 10 mg/L black carbon and 10 μmol/L lead acetate for 12.0 hours. The expression of ICAM-1 was detected by Western blotting. Results: i) The relative expression of ICAM-1, VCAM-1 and MAdCAM-1 in the cells of black carbon exposure group and ICAM-1 in the lead exposure group was higher than those in the control group (all P<0.05). The relative expression of ICAM-1 and MAdCAM-1 in the combined exposure group was higher than those in the other three groups (all P<0.05). The relative expression of VCAM-1 in cells of combined exposure group was higher than those in the control group and lead exposed group (all P<0.05). The relative expression of miR-326 in cells of the lead exposure group and black carbon exposure group was lower than those in the control group (all P<0.05). The relative expression of miR-326 in the combined exposure group was lower than that in the other three groups (all P<0.05). There was no significant difference between miR-328-3p and miR-542-3p in the four groups (all P>0.05). ii) The relative expression of ICAM-1 in cells of the miR-326 transfection control group cells was lower than that in the control group (P<0.05), while in the cells in the combined exposure and miRNA-326 transfection combined exposure group, it was higher than that in the control and miRNA-326 transfection control groups (all P<0.05), and lower in the miRNA-326 transfection combined exposure group than in the combined exposure group (P<0.05). Conclusion: Black carbon or lead exposure can upregulate the expression of ICAM-1, VCAM-1 and MAdCAM-1 in Z310 cells. Black carbon and lead combined exposure lead to a synergistic effect on upregulation of ICAM-1 and MAdCAM-1 expression, particularly ICAM-1. The combined exposure of black carbon and lead may upregulate the expression of ICAM-1 by downregulating the expression of miR-326.

Objective To investigate the effect of exposure to lead oxide nanoparticles (PbO NPs) on the polarization of microglia in mouse hippocampus. Methods i) Specific pathogen-free male C57 mice were randomly divided into control group, low-, medium- and high-dose groups, with 10 mice in each group. Mice in these three dose groups were intraperitoneally injected with PbO NPs suspension at doses of 5, 10 and 20 mg/kg per day, respectively, and mice in the control group were intraperitoneally injected with the same volume of 0.9% sodium chloride solution, five days per week for four weeks. ii) BV-2 cells were treated with PbO NPs at doses of 0.0, 2.5, 5.0 and 10.0 mg/L for 24 hours. iii) BV-2 cells were randomly divided into control group, PbO NPs group and triggering receptor expressed on myeloid cells 2 (TREM2) high expression + PbO NPs group. The cells in the control group received no treatment. The cells in PbO NPs group were exposed to 10.0 mg/L PbO NPs suspension for 24 hours. Cells in TREM2 high expression + PbO NPs group were transfected with Trem2 high expression plasmid, and then exposed to 10.0 mg/L PbO NPs suspension for 24 hours. iv) The mRNA expression of M1 markers ［nitric oxide synthase (iNos), cyclooxygenase 2 (Cox2), chemokine receptor 7 (Ccr7)］, M2 markers ［arginin-1 (Arg-1), transforming growth factor-β (Tgf-β), chemokine receptor 2 (Ccr2)］ and Trem2 of microglia was detected by real-time fluorescent quantitative polymerase chain reaction. The protein expression of iNOS, ARG-1 and TREM2 was detected by Western blotting. Results i) During the experiment, there was no significant difference in body weight of mice among these four groups (P>0.05). The relative expression of Cox2 and Ccr7 mRNA in the hippocampus of the mice increased in the low-dose group and the iNos, Cox2 and Ccr7 mRNA increased in the medium- and high-dose groups, compared with the control group (all P<0.05). The relative mRNA expression of Tgf-β in the hippocampus of the mice of low-dose group and Arg-1, Tgf-β and Ccr2 in the medium- and high-dose groups was decreased compared with the control group (all P<0.05). The mRNA relative expression of iNos, Cox2 and Ccr7 was increased (all P<0.05), while the mRNA relative expression of Arg-1, Tgf-β and Ccr2 was decreased (all P<0.05) in the hippocampus of the mice of high-dose group compared with the low-dose group. The relative expression of Trem2 mRNA and TREM2 protein in the hippocampus of mice of the medium- and high-dose groups was lower than those in the control group (all P<0.05). The relative expression of Trem2 mRNA and TREM2 protein in the hippocampus of mice of the high dose group was lower than those in the low- and the medium-dose groups (all P<0.05). With the increase of PbO NPs exposure dose, the relative expression of iNOS protein in hippocampus tissues of mice increased (P<0.01), and the relative expression of ARG-1 protein decreased (P<0.01). ii) With the increase of PbO NPs exposure dose, the relative expression of iNOS protein increased (P<0.01), and the relative expression of ARG-1 protein decreased (P<0.01) in BV-2 cells. The relative expression of iNOS protein in BV-2 cells of PbO NPs group and TREM2 high expression + PbO NPs group was increased (all P<0.05), and the relative expression of ARG-1 protein decreased (all P<0.05) compared with the control group. The relative expression of iNOS protein decreased (P<0.05), and the relative expression of ARG-1 protein increased (P<0.05) in BV-2 cells of TREM2 high expression + PbO NPs group compared with the PbO NPs group. Conclusion Exposure to PbO NPs could increase the M1 polarization and decrease the M2 polarization of microglia, with a dose-effect relationship. The M1 polarization of microglia decreased and M2 polarization increased after overexpression of Trem2 gene. The regulation of microglia polarization by TREM2 may be involved in the neurotoxic effects of PbO NPs.

Fluorosis is widely prevalent worldwide, and China is one of the countries with a high incidence of endemic fluorosis. In recent years, study on non skeletal damage caused by fluorosis, especially cardiovascular system damage, has gradually increased. Fluoride can cause cardio vascular arteriosclerosis, hypertension and other diseases, while cardiovascular disease have hidden and acute onset, and the mortality rate has increased year by year in recent years. At present, the mechanism of cardiovascular diseases caused by fluoride is not yet clear, and further clarification is needed. This article provides an overview of the effects of fluoride on cardiovascular diseases from three aspect: epidemiological investigation, animals experiment, and in vitro cell experiment. It categorizes and analyzes the pathogenesis, providing new ideas for the study of cardiovascular system damage caused by fluorosis.