Effect of miR-96-5p targeting IRS1 on apoptosis of PC12 cells induced by aluminum maltol / 中华劳动卫生职业病杂志

Objective: To investigate the effect and mechanism of miR-96-5p on apoptosis of PC12 cells induced by maltol aluminum. Methods: In January 2021, PC12 cells at logarithmic growth phase were divided into blank control group and low, medium and high dose group. Cells in each group were treated with 0, 100, 200 and 400 μmol/L maltol aluminum for 24 hours respectively. Cells were collected and cell apoptosis rates were detected by flow cytometry, miR-96-5p and insulin receptor substrate 1 (IRS1) mRNA expressions were detected by qRT-PCR, and the protein expression levels of cysteine protease 3 (Caspase3) 、activated cysteine protease 3 (Cleaved-caspase3) 、IRS1、phosphorylated protein kinase B (p-AKT) and phosphorylated glucose synthesis kinase 3β (p-GSK3β) were detected by western blotting. The target binding relationship between miR-96-5p and IRS1 was detected by double luciferase reporter gene experiment. The miR-96-5p inhibitor cells and negative control cells were constructed after transfecting PC12 cells with miR-96-5p inhibitor for 24 hours. The cells were divided into blank control group, negative control group, aluminum exposure group, aluminum exposure+negative control group, aluminum exposure+miR-96-5p inhibition group, and miR-96-5p inhibition group. After transfecting PC12 cells with miR-96-5p inhibition and IRS1 siRNA for 24 h, the cells were divided into aluminum exposure+miR-96-5p inhibition+negative control group and aluminum exposure+miR-96-5p inhibition+IRS1 inhibition group. The control group was cultured in complete culture medium, and cells in the aluminum exposure group were treated with 200 μmol/L maltol aluminum for 24 hours. Cells in each group were collected and the apoptosis rate, miR-96-5p and IRS1 mRNA expression levels, as well as protein expression levels of Caspase3, Cleaved-caspase3, IRS1, p-AKT, and p-GSK3β were measured. Results: After 24 hours of exposure, compared with blank control group and low-dose group, the apoptosis rates, relative expressions of Caspase3 and Cleaved-caspase3 proteins, and relative expressions of miR-96-5p in the medium and high-dose groups of PC12 cells were significantly increased, while the relative expression levels of IRS1 mRNA, IRS1, p-AKT and p-GSK3β proteins were significantly decreased (P<0.05). Targetscan prediction and double luciferase report experiment both proved that IRS1 was a direct target gene of miR-96-5p. In the transfection experiment, compared with the aluminum exposure group, the apoptosis rate, the relative expressions of Caspase3 and Cleaved-caspase3 proteins, the relative expression of miR-96-5p in the aluminum exposure+miR-96-5p inhibition group were significantly decreased, while the relative expression levels of IRS1 mRNA and IRS1, p-AKT and p-GSK3β proteins were significantly increased (P<0.05). In the IRS1 low expression experiment, compared with the aluminum exposure+miR-96-5p inhibition+negative control group, the apoptosis rate, the relative expressions of Caspase3 and Cleaved-caspase3 proteins in the aluminum exposure+miR-96-5p inhibition+IRS1 inhibition group were significantly increased, while the relative expression levels of IRS1 mRNA and IRS1, p-AKT and p-GSK3β proteins were significantly decreased (P<0.05) . Conclusion: The increased expression of miR-96-5p and the targeted inhibition of IRS1 may be one of the mechanisms of apoptosis of PC12 cells induced by maltol aluminum exposure.

Effect of exogenous trivalent iron ions on tau phosphorylation and aggregation in SH-SY5Y cells / 环境与职业医学

Background A large amount of iron deposition in the brain can cause neuronal damage by inducing oxidative stress, neuroinflammation, and abnormal mitochondrial function. In addition, iron deposition is also reported to be closely related to the pathogenesis of Alzheimer's disease (AD). The neurofibrillary tangles aggregated by tau hyperphosphorylation are one of the important pathological features of AD. Objective To investigate potential effect of exogenous trivalent iron ions on neuronal activity in human neuroblastoma (SH-SY5Y) cells and tau hyperphosphorylation and aggregation. Methods SH-SY5Y cells were treated with ferric chloride (FeCl3) at four concentrations (10, 100, 200, and 400 mg·L−1). Cell survival rate was then detected by CCK8 assay. Intracellular iron content was determined prussian blue (Perl's) by iron staining after 24 h exposure to FeCl3 at 10 or 200 mg·L−1. Transfection of tau-P301L plasmid was conducted to construct an AD-like cell model for tau overexpression. The differences in the expression of the phosphorylated tau (p-tau) protein in SH-SY5Y cells and SH-SY5Y cells with tau overexpression were detected by Western blotting after 24 h exposure to FeCl3 at 10 and 200 mg·L−1. After dilution with phosphate buffered saline (PBS), FeCl3, human tauR3, and FeCl3 + tauR3 were incubated at 37℃, and the fluorescence intensity reflecting tau aggregation level was measured by thioflavin T(ThT) method at 12, 24, 36, 48, 60, 72, 84, and 96 h, respectively. Meanwhile, after 96 h coincubation of FeCl3 and tauR3, the fibers formed by tau aggregation were observed under a transmission electron microscope (TEM). Results After 24 h of FeCl3 exposure, the cell survival rate of SH-SY5Y cells among all groups was statistically different (F=8.63, P<0.01). The cell survival rates in the 200 and 400 mg·L−1 groups were 80.1% and 68.7% of the control group, respectively (P<0.05). Compared with the control group, the nuclei of the 200 mg·L−1 FeCl3 group were mainly yellowish-brown after iron staining and the positive cell rate was up-regulated by 12.9% (P<0.01). After 24 h of FeCl3 exposure , the p-tau (Ser396) protein expression was statistically different among all groups (F=11.6, P<0.01). Compared with the control group, the p-tau protein expression level of SH-SY5Y cells in the 200 mg·L−1 group was up-regulated by 72.7% (P<0.01). After FeCl3-treated SH-SY5Y cells with tau overexpression for 24 h, the p-tau (Ser396) protein expression was statistically different among all groups (F=27.8, P<0.01). Compared with the tau group, the p-tau (Ser396) protein expression level of SH-SY5Y cells in the tau + 200 mg·L−1 group was up-regulated by 44.6% (P<0.05). Compared with the tauR3 group, the fluorescence intensities in the 84 and 96 h tauR3 + FeCl3 groups were up-regulated by 49.9% and 53.7% (P<0.01) respectively. After 96 h of coincubation, compared with the tauR3 group, FeCl3 + tauR3 aggravated tau aggregation and formed fiber deposition under TEM. Conclusion Exogenous trivalent iron ions may inhibit SH-SY5Y cell viability, promote the phosphorylation of tau in SH-SY5Y cells transfected with tau-P301L plasmid, and aggravate tauR3 aggregation and fiber production.

Mediating role of brain functional connectivity in cognitive decline induced by occupational aluminum exposure in workers / 环境与职业医学

Background Occupational aluminum exposure may associate with cognitive impairment in workers. At present, brain functional imaging data are not available for evaluating cognitive dysfunction in workers with occupational exposure to aluminum. The role of brain functional connectivity in cognitive decline associated with occupational aluminum exposure is not clear yet. Objective To explore potential mediating effect of brain functional connectivity value on cognitive decline induced by occupational aluminum exposure, to assess the relationship between cognitive impairment and brain functional connectivity, and to identify appropriate imaging evidence of early cognitive changes induced by occupational aluminum exposure. Methods This study used a subset data from a previous cross-sectional survey. Based on the data of aluminum-exposed workers, over 40 years old, aluminum-exposed working years >1 year, Montreal International Cognitive Assessment (MoCA) (Beijing version) score <26 points, 20 workers were selected as the case group, and 40 healthy workers with the same basic conditions (age, smoking, drinking, etc.) in non-aluminum production were selected as the control group with a 1∶2 matching ratio. The basic information of the subjects was collected, plasma aluminum level and cognitive function level were evaluated, and different brain functional connectivity values of default mode network (DMN) were measured by magnetic resonance imaging. The mediating effect analysis was conducted to examine the role of brain functional connectivity in the relationship between aluminum exposure and cognitive function. Results The plasma aluminum concentration of the case group was 1.76 times higher than that of the control group [(33.04±12.02) µg·L−1 vs (18.74±8.95) µg·L−1, P<0.05]; the MoCA score was 9.5 points lower [(18.35±2.64) vs (27.85±0.92), P<0.05]. The mean functional connection values of DMN1 and DMN2 in the case group were lower than those in the control group (P<0.05). The mean functional connection values of the left precuneus, left middle cingulate cortex, left superior medial gyrus, left precentral gyrus, and left cerebellum also decreased in the case group compared with the control group (P<0.05). Plasma aluminum concentration was negatively correlated with DMN1 functional connectivity value and MoCA scores (b=−0.004, 95%CI: −0.008–−0.001; b=−0.15, 95%CI: −0.233–−0.067; P<0.05). The mean functional connection values of DMN1 and DMN2 were positively correlated with MoCA scores (b=10.945, 95%CI: 5.574–16.316; b=10.107, 95%CI: 2.457–17.758; P<0.05). With the increase of plasma aluminum concentration, MoCA score decreased, but when the plasma aluminum concentration exceeded 19.50 µg·L−1, MoCA score decreased slowly. With the increase of the mean functional connectivity value of DMN1, MoCA score increased, but when the mean functional connectivity value of DMN1 exceeded 1.05 and continued to increase, the increase of MoCA score slowed down. The results of mediating effect analysis showed that the functional connectivity value of DMN1 partially mediated the relationship between plasma aluminum concentration and MoCA score, and the mediating effect was 25.80%. Conclusion Cognitive impairment in occupational aluminum-exposed workers is closely related to brain resting-state functional connectivity. There is a dose-response relationship of plasma aluminum concentration with DMN1 functional connectivity value and MoCA scores, and DMN1 functional connectivity value partially mediates the relationship between plasma aluminum concentration and MoCA scores. The brain functional connectivity value can be used as meaningful imaging data to study the cognitive decline induced by chronic aluminum exposure.

Exploring the mechanism of neurological damage by environmental factors and targeted preventive interventions / 环境与职业医学

Nervous system is the most important system of human body. More and more neurotoxic chemicals are found to inflict effects on nervous system, causing cognitive impairment. In this overview, the neurotoxic effects of environmental factors and their relationship with neurodegenerative diseases are briefly introduced. Further, aiming at the damage to the nervous system caused by metals such as aluminum, manganese, and iron, this special column attempted to evaluate the damage degree by combining objective imaging and cognitive scales and to explore the mechanism of toxicity (including neurotransmitter secretion disorders and tau protein hyperphosphorylation) by in vitro experiments. These papers also introduced intervention studies using hydrogen-rich water to target the damage of ionizing radiation to the nervous system and discussed the intervention mechanism as modulating the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT)/Caspase-9 pathway, and Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) signaling pathway.

Effect of aluminum-fluoride interactions on overall cognitive function of aluminum plant workers / 环境与职业医学

Background Aluminum and fluoride are neurotoxic, and aluminum exposure alone is closely related to the overall cognitive function of operational workers. It is unclear about the effect of aluminum and fluoride interactions on cognitive function. Objective To evaluate a potential interaction effect of blood aluminum and urinary fluoride on the overall cognitive function of workers working in an aluminum plant. Methods Using cluster sampling, 230 workers in the electrolysis workshop of an aluminum group company in Shanxi Province were selected, and plasma aluminum concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS) and urinary fluoride by ion-selective electrode. The study participants were divided into a low blood aluminum group and a high blood aluminum group according to the median (M) of blood aluminum concentration, and a low urinary fluoride group and a high urinary fluoride group by a predetermined cutoff point (2.160 mg·L−1). The Montreal Cognitive Assessment-Beijing (MoCA-BJ) was used to assess overall cognitive function of the workers. Logistic regression model was used to analyze the relationship between blood aluminum, urinary fluoride, and mild cognitive impairment (MCI), including multiplicative interaction analysis and correlation analysis; R language was used to fit an additive interaction model of blood aluminum and urinary fluoride on MCI and to calculate synergy index (S), relative excess risk due to interaction (RERI), and attributable proportion due to interaction (API). Results Among the 230 operational workers, the median blood aluminum concentration (P25, P75) was 40.11 (25.16, 58.89) µg·L−1, and there were 104 cases of abnormal urinary fluoride, with an abnormality rate of 45.2%. There was a multiplicative interaction (OR=7.783, 95%CI: 1.377, 43.991) and no additive interaction (RERI=0.030, 95%CI: −0.498, 0.559; API=0.018, 95%CI: −0.279, 0.316; S=1.049, 95%CI: 0.519, 2.118) for the effect between blood aluminum and urinary fluoride on overall cognitive function of the workers. The logistic regression analysis showed that the risk of MCI was 12.105 (95%CI: 2.802, 52.287) times higher in workers with both high blood aluminum and high urinary fluoride than in those with low blood aluminum and low urinary fluoride, after adjusting for selected influencing factors. Conclusion Occupational exposure related high blood aluminum and high urinary fluoride are risk factors for cognitive dysfunction, and the coexistence of both indicators increases the risk of MCI in workers with occupational aluminum exposure, with a multiplicative interaction.

Correlation between aluminum concentration and miR-134-3p expression in peripheral blood in occupational aluminum exposed workers / 环境与职业医学

Background Previous studies show that aluminum exposure could increase the expression of miRNA-134-3p, which is involved in the mechanism of aluminum induced learning and memory impairment. However, it has not been investigated whether the expression level of miRNA-134-3p in the peripheral blood of occupational aluminum exposed workers is related to the blood aluminum concentration yet. Objective To evaluate a potential correlation between aluminum concentration in peripheral blood and miR-134-3p expression in occupational aluminum exposed workers. Methods A total of 184 male aluminum workers in the electrolytic aluminum workshop, aluminum oxide workshop, and thermal power workshop of an aluminum plant in Shanxi were selected by cluster sampling. They were divided into four groups (Q1-Q4) according to the quartiles of blood aluminum concentration, with 46 workers in each group. The basic information of workers was collected by questionnaire survey, and the cognitive function of workers was evaluated by Montreal Cognitive Assessment (MoCA). The plasma of workers was collected, and the relative expression level of miR-134-3p in plasma was detected by real-time quantitative polymerase chain reaction (RT-PCR). The plasma aluminum concentration was detected by inductively coupled plasma mass spectrometry (ICP-MS). The associations among workers' peripheral blood aluminum concentration, plasma miR-134-3p expression level, and total MoCA score were evaluated by generalized linear models. Results The workers' medians (P25, P75) of blood aluminum concentration, plasma relative expression level of miR-134-3p, and MoCA score were 39.31 (25.30, 57.41) μg·L-1, 2.93 (2.29, 3.74), and 22.0 (20.0, 26.0), respectively. The results of the generalized linear model showed that after adjusting for age, body mass index, smoking, and alcohol consumption, compared with the Q1 group, blood aluminum in the Q2, Q3, or Q4 group had an impact on related plasma miR-134-3p expression level and total MoCA score (P<0.05). With increasing blood aluminum concentration, the expression level of miR-134-3p in workers' plasma gradually increased, showing a positive correlation (b>0, Ptrend<0.001), while the total score of MoCA gradually decreased, showing a negative correlation (b<0, Ptrend<0.001). As the expression level of miR-134-3p in plasma increased, the total score of MoCA gradually decreased, showing a negative correlation (b<0, Ptrend<0.001). There was a linear relationship between peripheral blood aluminum concentration and plasma relative expression level of miR-134-3p of the workers in the middle school and below group and the high school group (Ptrend<0.05), b (95%CI)=1.796 (1.248, 2.344) and 1.192 (0.874, 1.510), and no correlation was found in the workers in the college and above group (Ptrend>0.05). Conclusion Occupational aluminum exposure can lead to an increase in the expression level of miR-134-3p in plasma of workers, which may be related to a decrease in cognitive function of workers.

Role of STAT3 activated NLRP3 inflammasomes in BV2 cell inflammatory response induced by maltol aluminum / 环境与职业医学

Background Aluminum activates signal transducer and activator of transcription 3 (STAT3), causing microglial nucleotide-binding and oligomerization domain-like receptors protein 3 (NLRP3) inflammasome activation and inflammatory responses and producing neurotoxicity. Objective To explore the role of STAT3 regulated NLRP3 inflammasomes in the inflammatory response of mouse microglia cell line (BV2) cells induced by maltol aluminum [Al(mal)3]. Methods BV2 cells were assigned to five groups: one control group, three Al(mal)3 exposure groups (low, medium, and high doses at 40, 80, and 160 μmol·L−1 Al(mal)3 respectively), and one C188-9 (STAT3 antagonist) intervention group [10 μmol·L−1 C188-9 +160 μmol·L−1 Al(mal)3]. Cell viability was detected by CCK8. The expression of M1/M2 type markers, i.e. CD68/CD206, STAT3, p-STAT3, NLRP3, cleaved-casepase-1, and apoptosis-associated speck-like protein (ASC) in BV2 cells were detected by Western blotting, and proinflammatory cytokines interleukin (IL)-1β and IL-18, and anti-inflammatory cytokine IL-10 were determined by ELISA. Results The results of cell viability assay showed that cell viability gradually decreased with the increase of Al(mal)3 dose. Compared with the control group, the cell viability of the Al(mal)3 high-dose group was decreased by 18% (P<0.05); compared with the Al(mal)3 high-dose group, the cell viability of the C188-9 intervention group was significantly elevated by 14% (P<0.05). Compared with the control group, the expression levels of CD68 in the Al(mal)3 low-, medium-, and high-dose groups were elevated by 19%, 20%, and 21%, respectively (P<0.05); the expression level of CD206 in the Al(mal)3 high-dose group was decreased by 25% (P<0.05). Compared with the Al(mal)3 high-dose group, the expression level of CD68 in the C188-9 intervention group was reduced by 9% (P<0.05), whereas the expression level of CD206 was elevated by 22% (P<0.05). Compared with the control group, the p-STAT3 protein expression and the p-STAT3/STAT3 ratio in the Al(mal)3 high-dose group increased by 129% and 127%, respectively (P<0.05). Compared with the Al(mal)3 high-dose group, the p-STAT3 protein expression and the p-STAT3/STAT3 ratio in the C188-9 intervention group were decreased by 55% and 54%, respectively (P>0.05). Compared with the control group, the expression level of NLRP3 protein increased by 75% in the Al(mal)3 high-dose group (P<0.05), the expression levels of cleaved-casepase-1 protein increased by 28% and 35% in the Al(mal)3 medium- and high-dose groups (P<0.05), and the expression levels of ASC increased by 22%, 25%, and 53% in the Al(mal)3 low-, medium- and high-dose groups (P<0.05), respectively. Compared with the Al(mal)3 high-dose group, the expression levels of NLRP3, cleaved-casepase-1, and ASC proteins in the C188-9 intervention group decreased by 30%, 19%, and 32%, respectively (P<0.05). Compared with the control group, the levels of IL-1β in the Al(mal)3 medium- and high-dose groups increased by 18% and 21%, respectively (P<0.05), and the level of IL-18 in the Al(mal)3 high-dose group increased by 10% (P<0.05). Compared with the Al(mal)3 high-dose group, the IL-18 levels were reduced by 23% in the C188-9 intervention group (P<0.05). The content of anti-inflammatory factor IL-10 did not differ significantly between groups (P>0.05). Conclusion Aluminum can induce inflammatory responses in BV2 microglia and is predominantly pro-inflammatory, and the mechanism may involve STAT3 regulation of NLRP3 inflammasome secretion of inflammatory factors.

Effects of occupational aluminum exposure, types of alcohol consumption, and their interaction on cognitive function of workers / 环境与职业医学

Background Occupational aluminum exposure is closely related to cognitive impairment, and alcohol consumption is also closely related to cognitive dysfunction. Objective To explore the effects of types of alcohol consumption on cognitive function of occupational aluminum exposed workers. Methods A total of 181 workers aged from 23 to 56 years were selected by cluster sampling method in an electrolytic aluminum workshop of an aluminum plant in a region and in a maintenance workshop of another plant in the same region from July to August, 2019. Venous blood was collected, and plasma aluminum concentration was determined by inductively coupled plasma mass spectrometry. The study subjects were divided into low and high exposure groups based on the median blood aluminum level and type of work. Their basic information was collected by occupational health examination. Workers' cognitive function was assessed using the Montreal Cognitive Assessment Scale-Beijing Edition. Logistic regression was used to analyze the association between plasma aluminum concentration and cognitive impairment, and between the types of alcohol consumption (including Baijiu, red wine, and beer) and cognitive impairment, Unconditional logistic regression was used to fit multiplicative interaction model as well as additive interaction model of plasma aluminum concentration and the types of alcohol consumption, and to calculate the relative excess relative risk due to interaction (RERI) and attributable proportion due to interaction (AP). Results The M (P25, P75) concentrations of plasma aluminum were 40.01 (25.05, 60.56) µg·L−1 in the total study subjects, 25.16 (17.13, 34.78) µg·L−1 in the low exposure group and 60.56 (47.40, 68.53) µg·L−1 in the high exposure group. After adjusting the type of alcohol consumption, drinking, age, duration of exposure to aluminum, education, marital status, and smoking, the odds ratios for impairments of attention, language expression, and overall cognitive function in the high exposure group were 4.295 (95%CI: 1.912-9.648), 5.687 (95%CI: 1.355-23.867), and 2.720 (95%CI: 1.225-6.040) times of the low exposure group respectively. Besides, after adjusting blood aluminum concentration, total alcohol consumption, age, duration of exposure to aluminum, education, marital status, and smoking, the risk of attention impairment of the Baijiu drinkers was 2.613 (95%CI: 1.054 to 6.837) times of the non-Baijiu drinkers; the risks of impairment of visuospatial abilities and execution functions, language expression, delayed recall, and overall cognitive function of the beer drinkers were 3.165 (95%CI: 1.285-7.797), 17.898 (95%CI: 1.590-201.480), 3.118 (95%CI: 1.215-8.003), and 3.824 (95%CI: 1.736-8.423) times of the non-beer drinkers. There were both additive [RERI (95%CI): 1.745 (1.394-2.097), AP (95%CI): 0.415 (0.201-0.630)] and multiplicative (OR=3.591, 95%CI: 1.393-9.255) interactions between Baijiu intake and plasma aluminum concentration levels on the attention domain. The cognitive impairment attributed to the interactive effects of drinking Baijiu and plasma aluminum concentration in individuals with attention impairment accounted for 41.5%. There were both additive [RERI (95%CI): 5.955 (0.562-11.328), AP (95%CI): 0.829 (0.577-1.081)] and multiplicative (OR=42.174, 95%CI: 5.469-325.252) interactions between beer drinking and plasma aluminum concentration on the overall cognitive function. Among the individuals with overall cognitive impairment, the cognitive impairment caused by the interaction of beer drinking and plasma aluminum concentration accounted for 82.9%. Conclusion Occupation aluminum exposed workers' attention, language expression, and overall cognitive function are closely related to their plasma aluminum concentration. Plasma aluminum concentrations have interactions with Baijiu and beer consumption on cognitive impairment of workers.

Role and mechanism of miRNA-29a/PTEN pathway in neuronal network damage caused by aluminum / 环境与职业医学

Background Aluminum can cause synaptic plasticity damage in the hippocampus, probably due to blocked interneuronal signal transmission. MicroRNA-29a (miR-29a) can target phosphatase and tensin homolog deleted on chromosome ten (PTEN) expression and participate in the generation of neuronal networks, and may be involved in the effect of aluminum on the electrical activity of neuronal networks. Objective To study the role and mechanism of miR-29a-targeted PTEN in aluminum-induced neuronal network injury in primary hippocampal neurons of ICR mice treated with maltol aluminum [Al(mal)3] in vitro. Methods Primary hippocampal neurons of ICR mice born within 24 h were cultured in vitro. The purity of neurons was determined by labeling neuron-specific microtubule-associated protein 2 (MAP2) by immunofluorescence staining on day six of the culture; neurons were treated with different concentrations of Al(mal)3, and divided into a control group, and 10, 20, and 40 μmol·L−1 Al(mal)3 groups, and neuronal cell viability was detected by CCK-8 method. Al(mal)3 at 20 μmol·L−1 was selected for subsequent experiments to establish a neuronal network injury model for intervention. The lentivirus infection method was used to transfect miR-29a into neurons, which were divided into mNG, mNG+20 μmol·L−1 Al(mal)3, miR-29a, and miR-29a+20 μmol·L−1 Al(mal)3 groups, and micro-electrode array (MEA) was used to analyze the firing of neuronal network. The expressions of miR-29a and PTEN mRNA in each group were detected by real-time PCR (RT-PCR), and the expression of PTEN protein in each group was detected by Western blotting. Results The purity of primary mouse hippocampal neurons was greater than 90%, and the viability of the neurons was above 80% in all groups. At 48 h of the designed Al(mal)3 treatments, the changes in spike frequency, burst frequency, network burst frequency, and synchrony index of neurons cultivated on MEA plates in the control group were 207.56%±38.70%, 73.19%±46.43%, 75.42%±33.04%, and 117.13%±15.54%, respectively; the Al(mal)3 groups’ neuronal network electrical activity showed a decreasing trend. Compared with the control group, the spike frequency, burst frequency, network burst frequency, and synchrony index of the 20 and 40 μmol·L−1 Al(mal)3 groups significantly decreased (The changes were 171.70%±28.08%, 49.20%±23.23%, 50.20%±18.18%, and 85.45%±20.30%; 150.68%±26.15%, 43.43%±15.54%, 52.05%±26.31%, and 26.80%±8.29%, respectively, P < 0.05). Compared with the control group (1.00), the miR-29a relative expression levels were significantly decreased in the 20 μmol·L−1 Al(mal)3 group (0.74±0.09) and the 40 μmol·L−1 Al(mal)3 group (0.62±0.12) (P < 0.05); the relative expression levels of PTEN mRNA were significantly increased in the 20 μmol·L−1 Al(mal)3 group (1.32±0.12) and the 40 μmol·L−1 Al(mal)3 group (1.48±0.11) (P < 0.05); the PTEN protein relative expression levels (1.29±0.12 and 1.82±0.10, respectively) were also significantly increased (P < 0.05). By overexpressing miR-29a in mouse primary hippocampal neurons, the spike frequency, burst frequency, and network burst frequency were significantly higher in the miR-29a group compared with the mNG group (The changes were 252.80%±62.03%, 171.65%±56.30%, and 197.75%±27.12%, respectively, P<0.05). The mNG+20 μmol·L−1 Al(mal)3 group showed a significant decrease in all indicators of neuronal network electrical activity (The changes were 123.28%±47.31%, 66.62%±31.53%, 70.60%±12.48%, and 52.86%±20.26%, respectively, P < 0.05). Compared with the mNG+20 μmol·L−1 Al(mal)3 group, the electrical activity indicators of neuronal network were significantly higher in the miR-29a+20 μmol·L−1 Al(mal)3 group (The changes were 161.41%±42.13%, 101.16%±30.63%, 127.02%±29.58%, and 109.73%±15.61%, respectively, P < 0.05). Compared with the mNG group (1.00), the neuronal PTEN mRNA relative expression (0.67±0.11) and the PTEN protein expression (0.75±0.08) were decreased in the miR-29a group (P < 0.05); the PTEN mRNA relative expression (1.32±0.12) and the PTEN protein relative expression (1.46±0.15) in the mNG+20 μmol·L−1 Al(mal)3 group were increased (P < 0.05). Compared with the mNG+20 μmol·L−1 Al(mal)3 group, the PTEN mRNA relative expression (0.93±0.06) and the PTEN protein relative expression (0.92±0.09) were decreased in the miR-29a+20 μmol·L−1 Al(mal)3 group (P < 0.05). Conclusion Aluminum significantly inhibits the electrical activity of hippocampal neuronal networks, and miRNA-29a may be involved in the aluminum-induced impairment of hippocampal neuronal network electrical activity by regulating PTEN expression.

Effect of aluminum-maltolate on primary hippocampal neuron neurite damage by regulating CRMP2 through GSK-3β in mice / 环境与职业医学

Background Aluminum can induce irreversible structural and synaptic functional damage, and the associated mechanism may be related to the neurite damage regulated by glycogen synthase kinase-3β (GSK-3β)/collapsin response mediator protein 2 (CRMP2). Objective This experiment is conducted to investigate the effect of aluminum-maltolate [Al(mal)3] on primary hippocampal neuron neurites in mice, and reveal the role of GSK-3β-CRMP2 in this process. Methods The hippocampus of newborn ICR mice (≤ 24 h old) was used for primary neuronal cultures. On the 5th day in vitro (DIV5), neuron purity detection were performed by confocal laser scanning microscopy. On DIV7, the neurons were transfected with lentiviral vector-mediated mNeonGreen. On DIV10, the neurons with mNeonGreen fluorescence in good growth state were treated with Al(mal)3. The stage I experimental groups were blank control group, maltol group, 10 µmol·L−1 Al group, 20 µmol·L−1 Al group, and 40 µmol·L−1 Al group. Then 20 µmol·L−1 Al was used to establish a model of neurite injury and for the intervention. The stage II experimental groups were blank control group, dimethyl sulfoxide (DMSO) group, Al (20 µmol·L−1) group, SB (GSK-3β inhibitor, 1 µmol·L−1), and SB (1 µmol·L−1)+Al (20 µmol·L−1) group. CCK-8 method was used to detect the viability of neurons. The primary hippocampal neurons of mice were scanned with high content analysis system at 0 h and 48 h after Al or SB treatment, and the density and length of neurites were analyzed. Western blotting was used to detect the expression and phosphorylation levels of CRMP2 and GSK-3β in primary hippocampal neurons of mice. Results The immunofluorescence results showed that the purity of primary neurons was more than 90%. Compared with the blank control group in stage I, the cell viability rates of the 10, 20, and 40 µmol·L−1 Al groups were decreased after 48h of Al(mal)3 treatment (P<0.05), while the cell viability rate of the maltol group had no significant change. There was no significant difference in cell viability rate among the DMSO group, the SB group, and the control group after 48h of SB treatment, and the viability rate of neurons in the SB+Al group was higher than that in the Al group (P<0.05) in stage II. The 48 h/0 h ratios of average number and length of neurites in the control group were 90.13%±11.70% and 113.24%±8.34%, respectively. The 48 h/0 h ratios in the Al group were 56.47%±16.36% and 62.06%±6.75%, respectively, which were lower than those in the control group (P<0.05). The 48 h/0 h ratios of average number of neurites in the SB group (99.03%±21.83%) was not significantly different from that in the control group, but the 48 h/0 h ratio of average length of neurites in the SB group (128.72%±15.39%) was higher than that in the control group (P<0.05). The 48 h/0 h ratios of average number (72.59%±10.89%) and length of neurites (93.84%±14.65%) in the SB+Al group were significantly increased compared with those in the Al group (P<0.05). Western blotting results showed that: There was no significant difference in GSK-3β protein level among all groups; compared with the control group (1.00±0.18), the protein level of p-GSK-3β in the Al group (0.45±0.05) was significantly decreased, and that in the SB group (1.32±0.23) was significantly increased; the protein level of p-GSK-3β in the SB+Al group (0.80±0.05) was significantly higher than that in the Al group (P<0.05). Compared with the control group (1.00±0.07), the CRMP2 protein level in the Al group (0.66±0.11) was significantly decreased (P<0.05), while that in the SB group (1.01±0.02) was not significantly changed. Compared with the control group (1.00±0.13), the p-CRMP2 protein level in the Al group (1.50±2.18) was significantly increased, and that in the SB group (0.62±0.09) was significantly decreased (P<0.05); the protein level of p-CRMP2 in the SB+Al group (1.28±0.24) was lower than that in the Al group (P<0.05). Conclusion Aluminum may activate GSK-3β, increase CRMP2 phosphorylation level, and damage neurite growth.

Correlation between blood aluminum and fasting blood glucose level in occupational aluminum exposed workers / 中国职业医学

OBJECTIVE: To explore the relationship between occupational aluminum exposure and fasting blood glucose level in workers. METHODS: A cluster sampling method was used to select 178 occupational aluminum-exposed workers as the exposure group, and 178 workers without occupational aluminum exposure as the control group in a large aluminum factory in Shanxi Province. Glucose oxidase method was used to measure the fasting blood glucose level, and inductively coupled plasma mass spectrometry was used to measure the plasma aluminum level in these workers. A generalized linear model was used to analyze the correlation between plasma aluminum exposure level and fasting blood glucose in these workers. RESULTS: The blood aluminum level of workers in the exposure group was higher than that of the control group [median: 39.58 vs 16.67 μg/L, P<0.01]. The fasting blood glucose level of workers in the exposure group was higher than that of the control group [(5.33±0.79) vs(5.15±0.41) mmol/L, P<0.01]. The results of the generalized linear model analysis showed that the blood aluminum level of workers was positively correlated with their fasting blood glucose level after adjusting for age, body mass index, smoking, drinking, exercise, family history of diabetes, and incidence of diabetes(P<0.05). There was a dose-response relationship between the blood aluminum level and fasting blood glucose level of workers in the groups of junior high school and below and high school(all P_(trend)<0.01). There was no correlation found between blood aluminum level and fasting blood glucose level in the group of college and above(P_(trend)>0.05). There was a dose-response relationship between the blood aluminum level and the fasting blood glucose level in the workers in the non-exercise group(P_(trend)<0.01). There was no correlation found between the blood aluminum level and the fasting blood glucose level in the exercise group(P_(trend)>0.05). CONCLUSION: The blood aluminum level of workers exposed to occupational aluminum is positively correlated with their fasting blood glucose level. Higher education level or exercise can moderately reduce the effect of blood aluminum level on fasting blood glucose.

Effects of occupational aluminum exposure on the blood of male workers / 中国职业医学

OBJECTIVE: To explore the effect of occupational aluminum exposure on the blood of male workers. METHODS: A total of 249 male workers were selected as the research subjects by cluster sampling method in the electrolytic workshop of an aluminum plant. Blood samples were collected for determination of the blood aluminum concentration and blood routine. The subjects were divided into low-, medium-, and high-aluminuml groups based on the tertile of blood aluminum level(P_(33) is 13.9 μg/L, P_(67) is 37.7 μg/L). RESULTS: The red blood cell(RBC) count and hemoglobin level in patients of the high-aluminum group were lower than that of the low-aluminum group(P<0.05). There was no significant difference of the RBC count and hemoglobin level of patients in middle-aluminum group compared with that of the low-and high-aluminum groups(P>0.05). There was no statistical significant difference in white blood cell count and platelet count among the three groups(P>0.05). The results of the generalized linear regression model showed that the higher the blood aluminum level, the lower the RBC count and hemoglobin level of workers(P<0.05) after eliminating confounding factors such as age, length of service, education level, smoking, and drinking. CONCLUSION: Occupational aluminum exposure can cause a decrease of RBC count and hemoglobin level with a dose-effect relationship in workers.

Sub-chronic aluminum exposure inhibits synaptic plasticity in hippocampus of rats via inhibiting PI3K/AKT/mTOR signaling pathway / 中国职业医学

OBJECTIVE: To study the effect of sub-chronic aluminum exposure on synaptic plasticity in the hippocampus of rats and to explore the mechanism of phosphatidylinositol 3 kinase(PI3 K)/protein kinase B(AKT)/rapamycin target protein(mTOR) signaling pathway. METHODS: Specific pathogen free adult healthy male SD rats were randomly divided into control group and low-, medium-and high-dose groups based on body weight, with 10 rats in each group. Rats were treated with maltol aluminum solution at the concentrations of 0, 10, 20 and 40 μmol/kg body weight by intraperitoneal injection, 5 days per week for 3 months. After the exposure, rats were weighed. Morris water maze was used to test the learning and memory ability, and the two-electrode binding technique was used to record the long-term potentiation(LTP) amplitude in the hippocampus CA1 area of rats. The protein expression of PI3 K, AKT and mTOR in rat hippocampus tissues was detected by Western blot. RESULTS: After the exposure, the body weights of rats in the medium-and high-dose groups were lower than that of the control group(P<0.05). The results of the positioning navigation experiment showed that the escape latencies of the rats in the medium-and high-dose groups were shorter than that in the control group during the 2 nd to 4 th days of the experiment(P<0.05). The results of space exploration experiments showed that there was no statistical difference on the target quadrant retention time and the number of crossing the platform among the 4 groups(P>0.05). At 1, 30, and 60 min after high-frequency stimulation, the LTP amplitudes in the hippocampus CA1 area of the aluminum-treated groups were lower than that of the control group at the same time point(P<0.05), and the LTP amplitudes of hippocampus CA1 area of rats decreased with the increase of maltol aluminum exposure dose(P<0.01). The relative expression of PI3 K, AKT and mTOR protein in the hippocampus tissues of the aluminum-treated groups was lower than that of the control group(P<0.05), and the relative expression of the above three proteins decreased with the increase of the maltol aluminum exposure dose(P <0.01). CONCLUSION: Sub-chronic aluminum exposure could lead to dose-dependent inhibition of hippocampus synaptic plasticity in rats, thereby impairing the spatial learning ability of rats. This process may be related to inhibition of PI3 K/AKT/mTOR signaling pathway by aluminum.

Regulatory effect of metabolic glutamate receptor 1 on maltolate aluminum-induced synaptic plasticity in rats / 中国职业医学

OBJECTIVE: To observe the effect of maltolate aluminum on synaptic plasticity in the hippocampus of rats and to explore the regulatory effect and mechanism of metabotropic glutamate receptor 1(mGluR1). METHODS: Specific pathogen free healthy adult male SD rats were randomly divided into control group, aluminum group, aluminum agonist group and aluminum antagonist group, 8 rats in each group. The rats in the control group received no treatment; the rats in aluminum group were injected with 5 μL 10 mmol/L maltolate aluminum solution into the lateral ventricle; the rats in aluminum agonists and aluminum antagonist group were injected with 3 μL 10 mmol/L maltolate aluminum solution plus 2 μL 0.1 μmol/L mGluR1 agonist or 2 μL 0.2 μmol/L mGluR1 antagonists into the lateral ventricle, respectively.Maltolate aluminum solution was injected every 2 days and continued for 10 days. After maltolate aluminum exposure, the amplitudes of long-term potentiation(LTP) in hippocampal CA1 region of rats were measured, and the relative expression levels of mRNA and protein of mGluR1, N-methyl-D-aspartate receptor(NMDAR1) and protein kinase C(PKC) in hippocampus tissue of rats were detected by real-time fluorescence quantitative polymerase chain reaction and Western blotting. RESULTS: The amplitude of LTP in hippocampal CA1 region in aluminum group and aluminum agonist group was lower than that in the control group and the aluminum antagonist group(P<0.05). Compared with the control group, the relative expression of mGluR1 mRNA and protein in the aluminum group increased, the relative expression of PKC and NMDAR1 mRNA and protein in the aluminum group decreased(P<0.05). Compared with the aluminum group, the relative expression of mGluR1 mRNA and protein in the aluminum agonist group increased, while the NMDAR1 mRNA decreased(P<0.05); the relative expression of mGluR1 mRNA and protein in the aluminum antagonist group decreased, while the NMDAR1 mRNA and protein increased(P<0.05). Compared with the aluminum agonist group, the relative expression of mGluR1 mRNA and protein decreased, while the NMDAR1 mRNA and protein increased in the aluminum antagonist group(P<0.05). The relative expression level of PKC mRNA and protein in aluminum agonist group and aluminum antagonist group was not statistically significant(P>0.05), and there was no statistical significance in these two groups compared with control group and aluminum group(P>0.05). CONCLUSION: Maltolate aluminum exposure can inhibit synaptic plasticity by inhibiting LTP in hippocampus of rats, and the mechanism may be related to the regulation of NMDAR1 expression by mGluR1.

Determination of aluminum in blood of occupational workers by ICP-MS / 中华劳动卫生职业病杂志

Objective@#To establish a method for the determination of aluminum in blood, and to detect the aluminum content in the blood of occupational aluminum workers.@*Methods@#The morning blood of the aluminum workers was collected in an anticoagulation tube, and the supernatant was centrifuged. The supernatant was diluted with 4% nitric acid containing 1% Triton for 24 h at room temperature, and the supernatant was centrifuged. The supernatant was filtered and the blood aluminum concentration was measured by inductively coupled plasma mass spectrometry and quantified by external standard method.@*Results@#The detection limit of ICP-MS method was 0.39 μg/L, the linear range was 0-160 μg/L, the recoveries were 98.24%-99.65%, and the precision was 0.19%-0.28%. The recoveries of graphite furnace atomic absorption spectrophotometry (GFAAS) were 97.17%-111.18%, and the precision was 0.35%-0.44%. The average blood aluminum concentration of aluminum workers in the normal control group was (19.87±10.65) μg/L. The average blood aluminum concentration of aluminum workers in the expose group was (31.12±11.43) μg/L.@*Conclusion@#The method of ICP-MS for the determination of aluminum concentration in blood has a simple pretreatment process, high recovery rate, low detection limit and high precision, which is suitable for popularization.

The role of DFO in Al (mal) 3-induced ferroptosis in PC12 cells / 中华劳动卫生职业病杂志

Objective@#To investigate the mechanism of Al (mal) 3-induced ferroptosis in rat adrenal pheochromocytoma cells (PC12), to explore the effect of deferoxamine (DFO) .@*Methods@#Taken PC12 cells growing at logarithmic phase and divided into 6 groups: control group, 200 μmol/L Al (mal) 3 group, 0.5% DMSO group, 200 μmol/L DFO group, Al (mal) 3+DMSO group, Al (mal) 3+DFO group. DMSO and DFO were added to the DMSO group and the Al (mal) 3+DMSO group, the DFO group and the Al (mal) 3+DFO group for 2 h, respectively, Al (mal) 3 was then added to the Al (mal) 3 group, Al (mal) 3+DMSO group, and the Al (mal) 3+DFO group to a final concentration of 200 μmol/L. The cell viability was detected by CCK8, the morphology and ROS levels of PC12 cells was observed by inverted microscope, the cell proliferation toxicity and intracellular iron ion content were detected by colorimetry, the GSH content and GSH-PX activity were detected by biochemical method.@*Results@#Al (mal) 3 exposure significantly inhibited the growth of PC12 cells and destroyed the cell morphological structure, resulting in increased LDH activity and intracellular iron ion content in PC12 cells, decreased GSH content and GSH-PX activity, increased ROS levels; the combined treatment of Al (mal) 3+DFO can significantly improve the cell viability of PC12 cells, improved cell morphology, decreased cell LDH activity and intracellular iron ion content (P>0.05), increased GSH content and GSH-PX activity, decreased ROS levels.@*Conclusion@#Al (mal) 3 can induce ferroptosis in PC12 cells, DFO may inhibit ferroptosis by reducing intracellular iron levels and reducing oxidative damage.

The study of the effects of occupational aluminum exposure on TNFR1 expression and cognitive function / 中华劳动卫生职业病杂志

Objective@#To analyze the relationship between cognitive function and tumor necrosis factor receptor 1 (TNFR1) expression of occupational exposed workers to aluminum and provide the basis for the diagnosis of cognitive impairment.@*Methods@#140 cases Shanxi aluminum plant workers were collected in 2016 as the research object, including 70 potroom workers for exposure group, 70 non-electrolytic aluminum plant workers in the control group, respectively. Using mini mental status examination (MMSE), digit span test (DST), fuld object memory examination(FOME) and simple reaction time test(SRTT) evaluate the cognitive function of objects. Using graphite furnace atomic absorption method for the determination of plasma aluminum levels as an indicator of aluminum contact exposure of workers. Using RT-PCR method for detection of tumor necrosis factor receptor 1 (TNFR1) mRNA expression levels. And comparison group differences in cognitive and TNFR1 mRNA expression levels.@*Results@#The plasma aluminum content of exposed group (77.12±27.18) μg/L higher than the control group (55.6±28.69)μg/L (P=0.000); Compared to control group, FOME and MMSE score was significantly increased in the exposed group (P=0.000, P=0.000), SRTT scores significantly higher in the exposed group (P=0.001), DST no significant difference in the control group (P=0.893). Compared to control group, The mRNA expression of TNFR1 was significantly higher in the exposed group(P=0.002); Compared to control group, The protein expression of TNFR1 was significantly higher in the exposed group (P=0.002). By correlation analysis in exposure group, plasma aluminum content was negatively correlated with MMSE and the DST (r=-0.284, r=-0.331, P<0.05) and positively correlated with the SRTT, TNFR1 (mRNA) and TNFR1(protein)(r=0.255, r=0.333, r=0.987, P<0.01), MMSE was negatively related to TNFR1 (mRNA) and TNFR1 (protein) (r=-0.268, r=-0.255, P<0.05); DST was negatively correlated with the SRTT and TNFR1 (protein)(r=-0.267, r=-0.330, P<0.05); SRTT was positively correlated with TNFR1 (protein)(r=0.243, P<0.05); TNFR1 (mRNA) was positively correlated with TNFR1 (protein)(r= 0.340, P<0.01).@*Conclusion@#Cognitive function change of occupational exposed workers to aluminum was related to the increase of TNFR1 expression.

The effect of aluminum trichloride on expression of phosphorylated tau and Aβ in SH-SY5Y cells / 中华劳动卫生职业病杂志

Objective@#To investigate the expression of phosphorylated tau (p-tau) and Aβ in SH-SY5Y cells induced by aluminum or/and ApoE ε4 allele, and study the interaction between aluminum and ApoE ε4 allele.@*Methods@#SH-SY5Y cells were assigned to control group, 400 μmol/L AlCl3 group, ApoEε4 transfected group and 400 μmol/L AlCl3 with Apo Eε4 transfected group. The cell viability was measured by CCK-8 assay; the expressions of p-tau and Aβ was determined with ELISA Kit after AlCl3 exposure or or/and ApoE ε4 transfection.@*Results@#The viability of cells exposed to 400 μmol/L AlCl3 or/and ApoE ε4 transfected were significantly lower than that of controls (P<0.05) . The expressions of total tau, tau-181, tau-231, tau-396 and Aβ in 400 μmol/L Al3+ or/and ApoE ε4 transfected exposed cells showed significantly higher than those of controls (P<0.05) . Based on the factorial design, a significant interaction exists, and there is a synergistic effect between AlCl3 and ApoE ε4 (P<0.05) .@*Conclusion@#Aluminum and ApoE ε4 allele could increase expression of p-tau and Aβ deposition; there was a synergistic interaction between aluminum and ApoE ε4 allele on cell death, tau phosphorylation and Aβ deposition of SH-SY5Y.

Effects of subchronic aluminum exposure on long-term potentiation and activities of RAS and extracellular regulated protein kinases in rats / 中华劳动卫生职业病杂志

Objective@#To study the effects of subchronic aluminum exposure on LTP and activities of RAS and ERK in rats in vivo.@*Methods@#24 Wistar rats were randomly divided into control group、low-dose group、medium-dose group and high-dose group, and received saline (control group) or Al (mal) 3 (15 μmol、kg、30 μmol、kg or 45 μmol/kg) via intraperitoneal injection (i.p.) for 8 weeks, respectively. The fEPSP in CA1 region were recorded by field potentiation technique in vivo and the hippocampal activities of RAS and ERK were examined by ELISA.@*Results@#The fEPSP amplitudes of the control group were 1.90±0.19, 1.64±0.15 and 1.54±0.08 at 1, 30 and 60 min after HFS, respectively. The fEPSP amplitudes of the low-dose group were 1.40±0.06 at 60 min, which represented a statistically significant decrease compared to the control group (P<0.05) ; these values at 30min and 60min dropped to 1.33±0.20 and 1.12±0.07 in the medium-dose group (P<0.05) and further decreased to 1.05±0.05 and 0.91±0.10 in the high-dose group (P<0.05) . And the activity dose-dependent decreases were observed both in RAS and ERK: compared with the control group and the low-dose group, the activities of RAS and ERK of the medium-dose and high-dose group significantly decreased (P<0.05) and compared with the medium-dose group, the activities of the high-dose group statistically dropped (P<0.05) .@*Conclusion@#RAS and ERK may be related to the suppression of LTP by subchronic aluminum exposure and the RAS-MAPK transduction pathway may be involved in the damage of learning and memory induced by aluminum.

Influence of aluminum chloride exposure on embryonic development of zebrafish and neurobehavior of juvenile fish / 中华劳动卫生职业病杂志

Objective@#To investigate the influence of aluminum chloride (AlCl3) solution on the embryon-ic development of zebrafish and neurobehavior of juvenile fish.@*Methods@#The embryos of zebrafishat 6 hours after fertilization were exposed to AlCl3 solution at a concentration of 0, 55.0, 60.5, 66.6, 73.5, 80.5, or 100.0 mg/L, and embryonic hatching rates at 48 and 72 hours after fertilization were calculated. The embryos of zebrafishat 6 hours after fertilization were exposed to AlCl3 solution at a concentration of 0, 60.0, 72.0, 86.4, 103.7, or 124.4 mg/L, and the embryonic mortality rates at 12, 24, 48, 72, and 96 hours after fertilization were calculat-ed. The embryos of zebrafish at 6 hours after fertilization were exposed to AlCl3 solution at a concentration of 0, 50, 100, 200, 400, or 800 μg/L, and the changes in the neurobehavior of juvenile fish were observed after hatching, including touch-escape reaction at 72 hours after fertilization and autonomic movement and panic es-cape reflex at 7 days after fertilization.@*Results@#Compared with the 0 mg/L group, the≥66.6 mg/L group had a sig-nificant reduction in embryonic hatching rate at 48 and 72 hours after fertilization, and the ≥72.0 mg/L group had a significant increase in embryonic mortality rate at 96 hours after fertilization (P<0.05) . Compared with the 0 μg/L group, the≥100 μg/L group had a significant reduction in the number of times of touch-escape reaction (P<0.05) .Compared with the 0 and 50 μg/L groups, the 100-800 μg/L groups had significant reductions in total movement distance and average speed (P<0.05) . Compared with the dark period before illumination, all groups had a significant increase in movement speed during the light period of the panic escape reflex test (i.e., the third minute) (P<0.05) ; within 2 minutes after the light was turned off, there was no significant change in movement speed in the 0-200 μg/L groups (P>0.05) ; the 400 and 800 μg/L groups had a significant increase in movement speed (P<0.05) .@*Conclusion@#AlCl3 exposure may cause embryonic developmental disorder in zebrafish and ab-normal neurobehavior in juvenile fish.