AIM:To investigate the role and mechanism of histone demethylase lysine-specific demethylase 5A(KDM5A)in regulating the Notch signaling pathway in particulate matter 2.5(PM2.5)-induced cortical damage in off-spring mice.METHODS:A pregnancy PM2.5 exposure model was established using intratracheal nebulization.Pregnant mice were randomly divided into PBS control group and PM2.5 exposure group.The cortices of offspring mice were isolated 14 d after birth.Golgi staining,electron microscopy and other methods were used to detect damage to neurons and chroma-tin in the cortex.Western blot,RT-qPCR and immunofluorescence staining were used to detect the mRNA and protein ex-pression of KDM5A in the cortex,and the distribution of KDM5A co-localized with neural cells.A PM2.5-treated PC12 cell injury model was established to detect changes in cell viability and the expression of proteins related to cell proliferation and apoptosis.Further,Western blot,RT-qPCR and immunofluorescence staining were used to detect the mRNA and pro-tein expression of KDM5A,the distribution of KDM5A co-localized with neurons,and changes in the protein level of his-tone H3K4me3.Bioinformatics methods were used to predict the interaction between KDM5A and Notch1,which was fur-ther validated by transfection experiments.In both in vivo and in vitro PM2.5 exposure models,changes in key molecules of the Notch signaling pathway and the co-expression of Notch1 with neural cells in the cortices of 14-day-old offspring mice and PC12 cells were detected.RESULTS:Prenatal PM2.5 exposure during pregnant led to a reduction in the number of neurons and decreased dentritic complexity in the cerebral cortex of offspring at 14 d after birth.It also caused abnormal chromatin condensation within neuronal nuclei,decreased mRNA and protein expression of KDM5A protein in the cortex,increased H3K4me3 protein levels(P＜0.05),and a significant reduction in KDM5A/NeuN double-positive cells.Expo-sure to PM2.5 also resulted in decreased viability and proliferation,and increased apoptosis of PC12 cells,with reduced ex-pression of KDM5A mRNA and protein,increased H3K4me3 protein expression(P＜0.05),and a reduction in the num-ber of KDM5A/MAP-2 double-positive cells.Bioinformatics analysis and transfection experiments in PC12 cells revealed that Notch1 is a downstream target gene of KDM5A.Further in vivo and in vitro experiments found that PM2.5 exposure lead to decreased mRNA and protein expression of key Notch signaling molecules Notch1,Jagged1 and Hes1,and reduced numbers of Notch1/NeuN and Notch1/MAP-2 double-positive cells.CONCLUSION:Exposure to PM2.5 can lead to abnor-mal expression of KDM5A in the offspring's cerebral cortex,which may cause neuronal damage by down-regulating the Notch signaling pathway,a downstream target.This could be one of the significant factors contributing to the neurodevelop-mental disorders in offspring exposed to PM2.5 during pregnancy.

AIM:To investigate the role and mechanism of histone demethylase lysine-specific demethylase 5A(KDM5A)in regulating the Notch signaling pathway in particulate matter 2.5(PM2.5)-induced cortical damage in off-spring mice.METHODS:A pregnancy PM2.5 exposure model was established using intratracheal nebulization.Pregnant mice were randomly divided into PBS control group and PM2.5 exposure group.The cortices of offspring mice were isolated 14 d after birth.Golgi staining,electron microscopy and other methods were used to detect damage to neurons and chroma-tin in the cortex.Western blot,RT-qPCR and immunofluorescence staining were used to detect the mRNA and protein ex-pression of KDM5A in the cortex,and the distribution of KDM5A co-localized with neural cells.A PM2.5-treated PC12 cell injury model was established to detect changes in cell viability and the expression of proteins related to cell proliferation and apoptosis.Further,Western blot,RT-qPCR and immunofluorescence staining were used to detect the mRNA and pro-tein expression of KDM5A,the distribution of KDM5A co-localized with neurons,and changes in the protein level of his-tone H3K4me3.Bioinformatics methods were used to predict the interaction between KDM5A and Notch1,which was fur-ther validated by transfection experiments.In both in vivo and in vitro PM2.5 exposure models,changes in key molecules of the Notch signaling pathway and the co-expression of Notch1 with neural cells in the cortices of 14-day-old offspring mice and PC12 cells were detected.RESULTS:Prenatal PM2.5 exposure during pregnant led to a reduction in the number of neurons and decreased dentritic complexity in the cerebral cortex of offspring at 14 d after birth.It also caused abnormal chromatin condensation within neuronal nuclei,decreased mRNA and protein expression of KDM5A protein in the cortex,increased H3K4me3 protein levels(P＜0.05),and a significant reduction in KDM5A/NeuN double-positive cells.Expo-sure to PM2.5 also resulted in decreased viability and proliferation,and increased apoptosis of PC12 cells,with reduced ex-pression of KDM5A mRNA and protein,increased H3K4me3 protein expression(P＜0.05),and a reduction in the num-ber of KDM5A/MAP-2 double-positive cells.Bioinformatics analysis and transfection experiments in PC12 cells revealed that Notch1 is a downstream target gene of KDM5A.Further in vivo and in vitro experiments found that PM2.5 exposure lead to decreased mRNA and protein expression of key Notch signaling molecules Notch1,Jagged1 and Hes1,and reduced numbers of Notch1/NeuN and Notch1/MAP-2 double-positive cells.CONCLUSION:Exposure to PM2.5 can lead to abnor-mal expression of KDM5A in the offspring's cerebral cortex,which may cause neuronal damage by down-regulating the Notch signaling pathway,a downstream target.This could be one of the significant factors contributing to the neurodevelop-mental disorders in offspring exposed to PM2.5 during pregnancy.

The mesencephalic astrocyte-derived neurotrophic factor (MANF) has been recently identified as a neurotrophic factor, but its role in hepatic fibrosis is unknown. Here, we found that MANF was upregulated in the fibrotic liver tissues of the patients with chronic liver diseases and of mice treated with CCl₄. MANF deficiency in either hepatocytes or hepatic mono-macrophages, particularly in hepatic mono-macrophages, clearly exacerbated hepatic fibrosis. Myeloid-specific MANF knockout increased the population of hepatic Ly6C^high macrophages and promoted HSCs activation. Furthermore, MANF-sufficient macrophages (from WT mice) transfusion ameliorated CCl₄-induced hepatic fibrosis in myeloid cells-specific MANF knockout (MKO) mice. Mechanistically, MANF interacted with S100A8 to competitively block S100A8/A9 heterodimer formation and inhibited S100A8/A9-mediated TLR4-NF-κB signal activation. Pharmacologically, systemic administration of recombinant human MANF significantly alleviated CCl₄-induced hepatic fibrosis in both WT and hepatocytes-specific MANF knockout (HKO) mice. This study reveals a mechanism by which MANF targets S100A8/A9-TLR4 as a "brake" on the upstream of NF-κB pathway, which exerts an impact on macrophage differentiation and shed light on hepatic fibrosis treatment.

BACKGROUND:Tumor necrosis factor-α(TNF-α), a main cytokine inducing chondrocyte apoptosis of osteoarthritis, plays a regulatory role in the process of osteoarthritis. OBJECTIVE:To compare the rat models of chondrocyte apoptosis induced by different mass concentrations of TNF-α, thus providing theoretical basis for further study on the regulation of drugs on chondrocyte apoptosis. METHODS:Chondrocytes were isolated from the knee cartilage of 4-week-old Sprague-Dawley rats of clean grade by mechanical l col agenase digestion and were then incubated with different mass concentrations of TNF-αto induce apoptosis. The morphology of chondrocytes was observed under inverted phase contrast microscope, cel s were identified using immunohistochemical staining of type II col agen, as wel as the cel viability and apoptosis were detected by MTT and DAPI, respectively. RESULTS AND CONCLUSION:(1) In vitro, the cytoplasm of chondrocytes was stained brown-yel ow by using immunohistochemical staining of type II col agen. (2) At 48 hours, the apoptosis rate of chondrocytes induced by 10, 20 and 30μg/L TNF-αwas significantly higher than that of the 0μg/L TNF-α(P<0.01), and the apoptosis rate of chondrocytes induced by 40μg/L TNF-αwas significantly higher than that of the 10μg/L TNF-α(P<0.01). (3) The viability of chondrocytes induced by 10, 20 and 40μg/L TNF-αwas significantly lower than that of the 0μg/L TNF-α(P<0.01). In detail, the viability of chondrocytes induced by 20μg/L TNF-αwas lower than that of the 10μg/L TNF-α(P<0.05);the viability of chondrocytes induced by 40μg/L TNF-αwas significantly lower than that of the 10 and 20μg/L TNF-α(P<0.01, P<0.05). (4) These results suggest that 20μg/L TNF-αcan successful y induce the chondrocyte apoptosis model.

OBJECTIVE:To investigate the effect of electrolytes on the stability of the total parenteral nutrient(TPN) solutions.METHODS:The pH values and number changes of solution microparticles of 4 groups of TPN sample solutions that of different electrolytes were determined at 0h after preparation and 4 hours,8hours,12hours,16hours and 24hours,respectively after storage under room temperature(20℃～22℃). And the appearances of which were observed under naked eyes. RESUL_ TS:No changes were noted as for the pH of 4 groups of solutions within 24h.For the numbers of microparticles(≥5?m),those in Group 4(to which group valence 1 and valence 2 electrolytes were added) showed a rapid increase to peak value from the very start;while those of the other groups increased with the extension of storage time.Stratification appeared in Group 3(to which group,valence 2 electrolytes had been added) and Group 4(to which group,valence 1 and valence 2 electrolytes were added) 6 hours after preparation.Curdling reaction was noted in Group 2(to which group,valence 1 electrolytes had been added) at 12th hour.Neither sediments nor stratification appeared in Group 1(no electrolytes were added to which group).CONCLUSION:El_ectrolytes have certain influences on the stability of the TPN solutions.Care should be taken to the dosage of which at preparation.Furthermore,once prepared,the solution should be infused as soon as possible and the storage of which should not beyond 24h.