Objective To investigate whether exposure pathways influence the distribution pattern and toxicity of polystyrene nanoplastics(PSNPs)in hepatic cells.Methods Male C57BL/6J wild-type healthy mice aged 6 to 8 weeks old and weighed 18 to 22 g were administered with PSNPs via gavage or tail vein injection.Then,we tracked PSNPs distribution in the major organs of mice via an in vivo imaging system(IVIS).After that,we analyzed the cellular accumulation patterns in hepatic cell subpopulations(hepatocytes and Kupffer cells)using immunofluorescence and transmission electron microscopy(TEM).300 nm PSNPs were administered via gastric gavage or tail vein injection,and 70 nm PSNPs were injected via the portal vein.The cellular localization of PSNPs in the liver was analyzed using immunofluorescence.Subsequently,using AML-12 cells,a normal mouse liver cell line,as the parenchymal hepatocyte model,the uptake of PSNPs in AML-12 cells was analyzed by confocal laser scanning microscope(CLSM).Flow cytometry was performed to observe and quantify PSNPs uptake,and to analyze the underlying endocytosis mechanisms.IVIS was used to analyze PSNPs uptake features in vivo.Finally,using mouse macrophage line RAW264.7 as a Kupffer cell model and AML-12 cells as a parenchymal hepatocyte model,the cell-type-specific toxic effects induced by 100 μg/ml PSNPs were examined through transcriptomics and metabolomics analyses.Results IVIS revealed predominant hepatic accumulation of PSNPs regardless of exposure pathways via intragastric gavage or tail vein injection.Immunofluorescence/TEM demonstrated exposure pathway-dependent cellular distribution:intragastric PSNPs were localized mainly in hepatocytes,while intravenous PSNPs were accumulated in Kupffer cells.Changes in particle size(300 nm vs.70 nm)did not alter the cellular distribution pattern,while 70 nm PSNPs injected via the portal vein accumulated in Kupffer cells,which suggested that the cell-type-specific distribution of PSNPs in the liver was independent of PSNPs size and might be related to the transport of PSNPs in the gastrointestinal tract.Flow cytometry showed that PSNPs uptake by AML-12 was time-dependent and that the underlying endocytosis mechanism involved pathways mediated by clathrin(P<0.000 1),macropinocytosis(P=0.002 6),and lipid rafts(P<0.000 1).Findings on PSNPs distribution in blood revealed that the uptake of PSNPs by hepatocytes exhibited a rate saturation phenomenon.Multi-omics analysis identified distinct toxicity patterns:PSNPs disrupted lipid metabolism and neurotransmitter homeostasis in AML-12 cells and induced inflammation and oxidative stress in Kupffer cells.Conclusion Exposure pathways mediate the hepatic cell-type-specific distribution of PSNPs,thereby altering the downstream toxicological consequences induced by exposure to PSNPs.

Objective:To investigate the effect of tocilizumab (TCZ) on ventricular arrhythmias (VAs) after myocardial infarction (MI) in Sprague-Dawley rats and explore its potential mechanism.Methods:The random number table method was used to divide 32 adult male Sprague-Dawley rats into 4 groups: Sham group, TCZ group, MI group and MI+TCZ group, with 8 rats in each group. The MI model was established by ligation of the left anterior descending branch of the coronary artery in the MI and MI+TCZ groups, and only sutured without ligation in the Sham and TCZ groups. TCZ was injected into the left superior cervical ganglion (SCG) of rats in the TCZ and MI+TCZ groups after successful modeling or sham operation, and the same amount of normal saline was injected in the Sham and MI groups. 24 h after successful modeling, ECG of rats in each group was recorded, heart rate variability (HRV, including low frequency power (LF), high frequency power (HF), LF/HF ratio), QT interval, QTc interval were calculated, and left ventricular effective refractory period (ERP) and VA inducibility were measured. Myocardial infarct size and tissue changes were observed with triphenyl tetrazolium chloride staining and HE staining. Real-time PCR analysis was used to detect the messager RNA (mRNA) expression of interleukin-6 (IL-6) and signal transducer and activator of transcription (STAT) 3 in SCG and potassium voltage-gated channel subfamily D member 2 (Kcnd2) in myocardial infarction periphery. The expression of c-fos in SCG was detected by immunofluorescence staining.Results:Compared with Sham group and MI+TCZ group, rats in MI group had higher LF and LF/HF ratio, longer QT interval and QTc interval, more VAs induced, lower HF and shorter ERP ( P all<0.05). Triphenyl tetrazolium chloride staining and HE staining showed that rats in the Sham and TCZ groups had normal myocardial tissue structure, those in the MI group had severe myocardial injury, and those in the MI+TCZ group had less myocardial injury than those in the MI group. Real-ime PCR analysis showed that compared with Sham group and MI+TCZ group, mRNA expression levels of IL-6 and STAT3 in SCG of rats in MI group were higher, and mRNA expression level of myocardial Kcnd2 was lower ( P all<0.05). Immunofluorescence staining showed that the content of c-fos in SCG of rats in MI group was higher than that of Sham group and MI+TCZ group ( P all<0.05). Conclusions:TCZ may reduce neural activity of the SCG after MI by inhibiting the IL-6/STAT3 signaling pathway, thereby alleviating myocardial injury and inhibiting VAs.

BACKGROUND AND PURPOSE: This study investigated the contribution of white-matter hyperintensities (WMH) and lacunar infarcts (LI) to the risk of Alzheimer's disease (AD) in an elderly cohort in China. METHODS: Older adults who were initially cognitively normal were examined with MRI at baseline, and followed for 5 years. WMH were classified as mild, moderate, or severe, and LI were classified into a few LI (1 to 3) or many LI (≥4). Cognitive function was assessed using the Mini Mental State Examination and the Activities of Daily Living scale. RESULTS: Among the 2,626 subjects, 357 developed AD by the end of the 5-year follow-up period. After adjusting for age and other potential confounders, having only WMH, having only LI, and having both WMH and LI were associated with an increased risk of developing AD compared with having neither WMH nor LI. Moderate and severe WMH were associated with an increased risk of developing AD compared with no WMH. Furthermore, patients with many LI had an increased risk of developing AD compared with no LI. CONCLUSIONS: Having moderate or severe WMH and many LI were associated with an increased risk of developing AD, with this being particularly striking when both WMH and LI were present.
Activities of Daily Living ; Adult ; Aged* ; Alzheimer Disease* ; China* ; Cognition ; Cohort Studies ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Strikes, Employee ; Stroke, Lacunar*

Objective To study the effect of hypertension on motor function in Parkinson's disease (PD) patients with white matter lesion (WML).Methods Two hundred and nineteen PD patients with WML were divided into hypokinesia group (n=137) and non hypokinesia group (n=82).The patients were followed up for 1 year.The relationship of vascular risk factors with hypertension and hypokinesia was analyzed.Results The age was older,the incidence of hypertension,DM and lipidemia was higher,the SBP and DBP were higher in hypokinesia group than in non hypokinesia group (P＜0.01,P＜0.05).Logistics regression analysis showed that age,hypertension and DM were the risk factors for hypokinesia in PD patients with WML (OR =1.78,95 ％CI:1.43-2.14,OR =1.97,95 ％0 CI:1.49-2.52,OR =1.63,95 ％ CI:1.31-1.94).Further analysis showed that grade 2 and 3 hypertension were closely related the risk of hypokinesia in PD patients with WML(OR=1.62,95％CI:1.29-1.95;OR=2.19,95％CI:1.49-2.91).Conclusion Hypertension,especially grade 2 and 3 hypertension,can aggravate hypokinesia in PD patients with WML.