Experimental study of Lentinan antagonizes against hepatic lipid deposition induced by sodium arsenite in mice / 公共卫生与预防医学

Objective To investigate the ameliorative effect of Lentinan (LNT) on sodium arsenite (SA)-induced hepatic lipid deposition in mice. Methods C57BL/6 mice were used as the experimental subjects, which were divided into control group, SA-exposed group, LNT + SA-exposed group and LNT control group. Blood and liver tissue samples were collected at the end of the experiment, and serum glutathione transaminase (ALT) and glutathione aminotransferase (AST) levels were detected by enzyme-linked immunosorbent assay (ELISA). A part of liver tissues was stained with hematoxylin-eosin (HE) or oil red O to observe the characteristics of liver pathological damage and lipid deposition, and another part of liver tissues was used to detect triglyceride (TG) and Adiponectin (APN) levels by ELISA. Results Compared with control group or LNT control group, SA-exposed group showed the increased levels of AST and ALT, showing the characteristics of liver histopathological damage and lipid deposition, and the APN level decreased while the TG level increased (P<0.05). Compared with SA-exposed group, the levels of AST and ALT decreased in LNT + SA-exposed group, showing the reduced degree of liver tissue damage and lipid deposition, and APN level upregulated while TG level downregulated (P<0.05). Conclusion Chronic SA exposure induces liver function damage, APN downregulation and lipid deposition in C57BL/6 mice, while LNT intervention leads to the significantly improvement of hepatic damage and lipid deposition, which may be related to the elevated APN level in liver.

Effects of sodium arsenite on proliferation, apoptosis and Hippo-YAP pathway of PC12 cells / 中国药理学通报

To investigate the effects of sodium arsenite(NaAsO

Effect of sciadopitysin on sodium arsenite-induced senescence of rat hippocampal neurons / 环境与职业医学

Background In addition to the typical signs of skin damage, long-term arsenic exposure is often accompanied by signs and symptoms of neurobehavioral abnormalities. Objective To investigate potential intervention effect of sciadopitysin on senescence of neurons induced by sodium arsenite in rats and possible underlying mediating effect of cell cycle-related transcription factor E2F1. Methods SH-SY5Y cells were treated with 4 μmol·L−1 sodium arsenite for 24 h and intervened with 50 μg·mL−1 Ginkgo biloba extract (EGb761) or four major biflavonoids in Ginkgo biloba leaves (isoginkgetin, bilobetin, sciadopitysin, and ginkgetin) for 24 h respectively. Then, cell viability was measured by CCK-8 assay. Thirty-two 180-200 g SPF rats were randomly divided into a control group, an arsenic treatment group (10 mg·L−1), a Ginkgo biloba extract intervention group (10 mg·kg−1), and a sciadopitysin intervention group (10 mg·kg−1), 8 rats in each group, half male and half female. The rats were treated with sodium arsenite by free drinking water for 3 consecutive months, and the intervention treatment was conducted after 2 months of poisoning with drug intake by gavage for 1 month. HE staining was used to detect structural changes in the hippocampus, while Nissl's staining was used to detect changes in hippocampal morphology and neuron numbers. Moreover, senescence-associated β galactosidase (SA-β-gal) staining and Western blotting were used to detect senescence of hippocampal neurons and the expression level of E2F1, respectively. Results Compared to the arsenic treatment group, EGb761 and the four biflavonoids in Ginkgo biloba leaves effectively antagonized the inhibitory effect of sodium arsenite on cell viability (all Ps＜0.05), and sciadopitysin showed better restoration of cellular viability than Ginkgo biloba extract (P＜0.05). The results of HE staining and Nissl's staining showed that the hippocampal neurons in the arsenic treatment group were reduced in cell count and the synaptic structure was abnormal, with swelling, nuclear shrinkage, and vacuole, compared with the control group. The results of SA-β-gal staining showed that the number of senescent cells in the arsenic treatment group (15.75±3.01) was significantly increased compared with the control group (2.88±0.84) (P＜0.05); the numbers of senescent cells in the Ginkgo biloba extract group (9.38±1.92) and the sciadopitysin treatment group (7.75±2.38) were significantly decreased compared with the arsenic treatment group (all Ps＜0.05). The results of Western blotting showed that compared with the control group, the expression of E2F1 protein in hippocampus of the arsenic treatment group was significantly decreased (1.00±0.17 vs. 0.65±0.19, P<0.05); compared with the arsenic treatment group, the protein expression level of E2F1 in hippocampus of the sciadopitysin treatment group (0.89±0.18) was significantly recovered (P<0.05); compared with Ginkgo biloba extract (0.68±0.19), sciadopitysin had a better recovery effect on E2F1 expression level (0.89±0.18) (P＜0.05). The results of correlation analysis showed that the E2F1 protein expression level was negatively correlated with the positive rate of SA-β-gal staining in hippocampal neurons (r=−0.518, P＜0.05). Conclusion Sciadopitysin is an effective component of Ginkgo biloba extract. It can effectively inhibit the senescence of hippocampal neurons induced by sodium arsenite, and E2F1 may play an important mediating role.

Expressions and roles of key enzymes in serine synthesis pathway in NaAsO2-treated HaCaT cells / 环境与职业医学

Background The key enzymes of serine synthesis pathway (SSP) play an important role in tumor growth, proliferation, and invasion, but their roles in arsenic carcinogenesis are unclear. Objective To observe the effects of NaAsO2 treatment on the expressions of key enzymes [such as phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH)] of SSP and on the ability to proliferate and migrate in human immortalized skin keratinocytes (HaCaT) and NaAsO2-induced malignantly transformed HaCaT (T-HaCaT), and to explore the roles of SSP key enzymes in arsenic carcinogenesis. Methods (1) The T-HaCaT cells constructed earlier by our research team were divided into a passage control (0 μmol·L−1 NaAsO2) group, a T-HaCaT (0.5 μmol·L−1 NaAsO2) group, a NCT503 (PHGDH inhibitor, 25 μmol·L−1) group, and a NCT503 (25 μmol·L−1) + T-HaCaT (0.5 μmol·L−1 NaAsO2) group. Western blotting was used to detect the protein expression levels of SSP key enzymes in the passage control group and the T-HaCaT group. CCK8 assay and cell scratch test were used to detect the proliferation and migration rates of cells in each group respectively. (2) Well-grown logarithmic-phase HaCaT cells were treated with 0, 0.625, 1.25, and 2.5 μmol·L−1 NaAsO2 for 0, 24, 48, and 72 h to detect cell proliferation rate and protein expression levels of SSP key enzymes. In the subsequent experiment, HaCaT cells were pretreated with 25 μmol·L−1 NCT503 for 6 h, and then treated with 2.5 μmol·L−1 NaAsO2 for 72 h continuously. The experimental groups included a control (0 μmol·L−1 NaAsO2) group, an exposure (2.5 μmol·L−1 NaAsO2) group, a pretreatment (25 μmol·L−1 NCT503) group, and a pretreatment (25 μmol·L−1 NCT503) + exposure (2.5 μmol·L−1 NaAsO2) group, to detect the proliferation rate of cells in each group. Results The protein expression level of PHGDH in the T-HaCaT group were 1.60 times higher than that in the passage control group (P<0.05), and its proliferation rate (177.51%±14.69%) and migration rate (53.85%±0.94%) were also higher than the passage control group’s (100.00%±0.00% and 24.30%±2.26%) (both Ps<0.05), respectively. After the NCT503 intervention, the proliferation rate (144.97%±8.08%) and migration rate (35.80%±0.99%) of cells in the NCT503 + T-HaCaT group were lower than those in the T-HaCaT group (both P<0.05). The proliferation rate of HaCaT cells after NaAsO2 exposure for 72 h increased with the increase of exposure concentration (r=0.862, P<0.05), and consistently, the protein levels of SSP key enzymes in HaCaT cells in each exposure group were higher than those in the control group (all P<0.05). The proliferation rate of HaCaT cells treated with 2.5 μmol·L−1 NaAsO2 increased with the extension of exposure time (r=0.775, P<0.05), which was consistent with the changes of PHGDH levels in cells. After the NCT503 intervention, the proliferation rate of the pretreatment + exposure group was significantly lower than that of the exposure group (P<0.05). Conclusion The key enzymes of SSP may play an important role in the proliferation of T-HaCaT cells induced by NaAsO2.

Role of mitogen-inducible gene 6 in the activation of human hepatic stellate cells and deposition of extracellular matrix induced by sodium arsenite / 环境与职业医学

Background Arsenic is a well-known environmental toxicant. Hepatic fibrosis could occur dueto excessive or long-term exposure to arsenic, while associated molecular mechanisms remain undefined. Mitogen-inducible gene 6 (Mig-6) exhibits a protective effect on numerous diseases or cancers. However, the specific role of Mig-6 in the mechanisms of arsenite-induced hepatic fibrosis remains indistinct. Objective To investigate the specific role of Mig-6 in the activation of hepatic stellate cells (HSC) and the deposition of extracellular matrix (ECM) induced by sodium arsenite (NaAsO2). Methods Human hepatic stellate cells (Lx-2) were treated with 0, 1.875, 3.75, 7.5, and 15 μmol·L−1 of NaAsO2 for 24 h, or with 7.5 μmol·L−1 NaAsO2 for 0, 12, 24, 48, and 72 h. Additionally, Lx-2 cells were transfected by pcDNA3.1(+)/Mig-6, then treated with 7.5 μmol·L−1 NaAsO2 for 24 h; a blank control group, a pcDNA3.1(+)-control group, a pcDNA3.1(+)/Mig-6 group, and an arsenic (7.5 μmol·L−1 NaAsO2) group were also set up. After transfection, the cells and culture supernatants were collected, and the protein levels of Mig-6, α-smooth muscle actin (α-SMA), and transforming growth factor-β1 (TGF-β1) in Lx-2 cells were identified by Western blotting analysis; moreover, the secretion levels of main ECM components in supernatants such as hyaluronic acid (HA), laminin (LN), collagens IV (COL-IV), and procollagen-III (PIIINP) were tested by ELISA. Results The Mig-6 expression decreased in the 3.75, 7.5, and 15 μmol·L−1 NaAsO2 groups (0.561±0.095, 0.695±0.048, and 0.401±0.030) compared to the control group (1.000±0.000) in Lx-2 cells (P<0.05). After administration with 7.5 μmol·L−1 of NaAsO2 for 24, 48, and 72 h, the Mig-6 expression (0.856±0.036, 0.515±0.077, 0.491±0.060) decreased compared with the 0 h group (1.000±0.000) (P<0.05). After over-expression of Mig-6, the results of Lx-2 activation related protein levels showed that compared to the control group, the α-SMA and TGF-β1 expression were up-regulated in the arsenic group (P<0.05); meanwhile, the α-SMA and TGF-β1 in the Mig-6 over-expression combined arsenic exposure group reduced compared to the arsenic (7.5 μmol·L−1) group (P<0.05). The results of ELISA showed that compared with the control group, the HA, LN, PIIINP, COL-IV in the arsenic group were up-regulated (P<0.05); while compared to the arsenic group, the HA, LN, PIIINP, and COL-IV in the Mig-6 over-expression combined with arsenic exposure group were decreased (P<0.05). Conclusion Arsenic down-regulates Mig-6 expression in HSC, and over-expression of Mig-6 can reverse the activation of HSC and ECM deposition induced by arsenic exposure. It suggests that Mig-6 plays a protective role in arsenic-induced HSC activation and ECM deposition.

Mechanism of BCL2L2-PABPN1 expression induced by sodium arsenite and its metabolites in 16HBE cells / 中国职业医学

@#Objective - - （BCL2L2）- （ ） To investigate the differential expression of the fusion gene BCL 2 like protein 2 poly A （PABPN1） （ ） binding protein nuclear 1 induced by sodium arsenite SA and its methylated metabolites in 16HBE cells and the Methods ） ， related mechanism. i The 16HBE cells exposed to SA at concentrations of 1.5 3.0 and 4.5 µmol/L were set as -， - - low medium and high dose arsenic exposure groups. The 16HBE cells exposed to 4.5 µmol/L monomethylarsonic acid （ ）， （ ） ， MMA dimethylarsonic acid DMA and SA were set as MMA group DMA group and SA group. The 16HBE cells without ， BCL2L2-PABPN1 toxic stimulation were set as control group. After the cells were cultured for 48 hours the expression of was - （ - ） ） （ ） detected by quantitative real time polymerase chain reaction qRT PCR . ii Two small interfering RNA siRNA silencing 基金项目：国家自然科学基金（ ）； 年云南省科技厅昆明医科大学应用基础研究联合专项面上项目 82160607 2021 （ ） 202101AY070001-054 作者简介：施雅（ —），女，在读大学本科生，主要从事劳动卫生与环境卫生学研究；尹锦瑶（ —），女，在读劳动卫生与环境卫 2001 1995 生学硕士研究生，主要从事劳动卫生与环境卫生学研究；施雅和尹锦瑶为共同第一作者 通讯作者：何越峰教授，博士研究生导师，- ： E mail heyuefeng@kmmu.edu.cn中国职业医学 年 月第 卷第 期 ， ， ， · · 2022 10 49 5 Chin Occup Med October 2022 Vol.49 No.5 523 BCL2L2-PABPN1， - fragments were designed and transfected into 16HBE cells to knockdown which were set as siRNA 1 group - - BCL2L2-PABPN1 and siRNA 2 group. Non transfected control group without knockdown of transfection was set up. After ， BCL2L2-PABPN1 - culturing for 48 hours the expression level of in the three groups of cells was detected by qRT PCR. The cell - survival rate and early apoptosis rate were detected by MTS method and JC 1 mitochondrial membrane potential detection ， （ ） ， method respectively. The apoptosis was detected by Hoechest33342/propidium iodide PI double staining and the expression - Results ） level of P53 signaling pathway related proteins was detected by Western blotting. i The relative expression of BCL2L2-PABPN1 （P ） BCL2L2- in 16HBE cells increased with the increasing SA doses <0.01 . The relative expression of PABPN1 - ， - - in high dose arsenic exposure was higher than that in control group low dose and medium dose arsenic exposure （ P ） BCL2L2-PABPN1 ， groups all <0.05 . The relative expression of in SA group was higher than those in control group MMA （ P ） BCL2L2-PABPN1 group and DMA group all <0.05 . The relative expression of showed no significant difference between ， （ P ） ） BCL2L2-PABPN1 control group MMA group and DMA group all >0.05 . ii The relative expression levels of and cell - - - （ P ） survival rate in siRNA 1 group and siRNA 2 group were lower than those in non transfected control group all <0.05 . ， （P ） However there was no significant difference in the early apoptosis rate among the three groups >0.05 . The results of - Hoechest33342/PI double staining showed that the number of nuclear shrinkage and early apoptotic cells in siRNA 1 group and - - ， - siRNA 2 group was higher than that in non transfected control group. The relative protein expression levels of P53 phospho ， - - ， - - （ P ） p53 BCL 2 associated death promoter P21 and cytochrome C in siRNA 1 group and siRNA 2 group were higher all <0.05 , - - P and the relative protein expression levels of P53 up regulated modulator of apoptosis were lower (all <0.05), when compared - Conclusion with the non transfected control group. SA may block the apoptosis of 16HBE cells by inducing the expression of BCL2L2-PABPN1 fusion gene . The mechanism may be related to the activation of P53 signaling pathway. The SA methylated BCL2L2-PABPN1 BCL2L2-PABPN1 - metabolites MMD and DMA had no effect on the expression of . may affect anti apoptosis BCL2L2 PABPN1 through affecting the synergistic effect of and genes.

Effects of sodium arsenite on mitochondrial function and expression of SIRT1/PGC-1α pathway-related proteins in human normal liver cell / 环境与职业医学

Background Long-term exposure to arsenic can cause liver injury of varying degrees. Mitochondrial damage may be an early key event of arsenic-induced liver injury. Silent mating type information regulation 2 homolog 1 (SIRT1)/ recombinant peroxisome proliferators-activated receptor gamma coactivator 1 alpha (PGC-1α) is an important pathway regulating mitochondrial mass and function. However, whether arsenic-induced liver injury is related to mitochondrial dysfunction mediated by SIRT1/PGC-1α pathway remains unclear. Objective To investigate potential effects of sodium arsenite (NaAsO2) on mitochondrial function and expressions of SIRT1/PGC-1α pathway-related proteins in human normal liver cell. Methods Human normal liver cells (MIHA cells) were used as the research object. MIHA cells were treated with different concentrations of NaAsO2 (0, 5, 10 and 20 μmol·L−1) for 24 h, and the cells were collected for study. The ultrastructure of mitochondria was observed by transmission electron microscopy, adenosine triphosphate (ATP) concentration by fluorescence method, mitochondrial membrane potential (MMP) level by flow cytometry, and SIRT1, PGC-1α and their downstream nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM) protein expression levels by Western blotting. One-way analysis of variance and trend test were used for data statistical analysis. Results The viability of MIHA cells decreased gradually with the increase of NaAsO2 concentration (F=6495.47, P<0.001). The transmission electron microscope observation showed that the size of mitochondria in the 10 μmol·L−1 NaAsO2 treatment group was different, and the mitochondria were swollen or elongated in a rod-like shape. The mitochondria in the 20 μmol·L−1 NaAsO2 treatment group swelled like air spheres or vacuoles. The ATP concentration and MMP level of MIHA cells gradually decreased with the increase of NaAsO2 concentration (Ftrend of ATP=172.28, Ftrend of MMP=59.91, both Ps<0.001). Compared with the control group, the protein expression levels of SIRT1, PGC-1α, NRF1, and TFAM were not significantly changed in the 5 μmol·L−1 NaAsO2 treatment group, while the protein expression levels of SIRT1, PGC-1α, and TFAM were decreased in the 10 μmol·L−1 NaAsO2 treatment group, and the protein expression levels of SIRT1, PGC-1α, and NRF1 were decreased in the 20 μmol·L−1 NaAsO2 treatment group. The results of trend test showed that the protein expression levels of SIRT1, PGC-1α, NRF1, and TFAM decreased gradually with the increase of NaAsO2 concentration (Ftrend of SIRT1=47.07, P<0.001; Ftrend of PGC-1α=15.17, P<0.01; Ftrend of NRF1=13.54, P<0.01; F trend of TFAM=4.20, P<0.05). Conclusion The down-regulation of SIRT1/PGC-1α and its downstream NRF1 and TFAM may be involved in NaAsO2-induced mitochondrial dysfunction in liver cells.

Effects of chronic exposure to sodium arsenite on liver damage in rats / 预防医学

Objective@#To examine the effect of chronic exposure to sodium arsenite on liver damages in rats. @*Methods@#Fifty-six healthy adult SD rats (28 males and 28 females) were randomly divided into 4 groups. Rats in the low-, medium- and high-dose groups were given sodium arsenite solutions at doses of 2, 10 and 50 mg/L for successive 24 weeks, while animals in the control group were given deionized water. The rat body and liver weights were measured and the liver coefficient was estimated. The urine arsenic level was detected using atomic fluorescence spectrometry, and hepatic tissue sections were stained with uranium acetate and lead citrate for morphological observations under an electron microscope. @*Results@#The body weights of both male and female rats appeared a tendency towards a rise with the duration of exposure to sodium arsenite (male rat: Wald χ2=3 610.621, P<0.001; female rat: Wald χ2=2 186.217, P<0.001, and there were no significant differences in the rat body weight 24 weeks post-exposure to sodium arsenite in each group, while there was an interaction between time and group (male rat: Wald χ2=15.874, P=0.001; Wald χ2=9.460, P=0.024). There were significant differences in the rat liver weight and liver coefficient in each group (male rat: F=18.964 and 29.968, both P<0.001; female rat: F=11.919 and 15.070, both P<0.001), with the lowest liver weight (10.17±1.15) g and liver coefficient (1.99±0.21)% measured in male rats in the high-dose group, and the highest liver weight (12.91±1.29) g and liver coefficient (4.10±0.56)% in female rats in the high-dose group. The median urine arsenic levels (interquartile range) were 25.60 (30.27), 146.56 (101.06), 1 034.68 (600.06) and 3 796.98 (19 966.89) μg/L in rats in the control, low-dose, medium-dose and high-dose groups, respectively (χ2=50.211, P<0.001), and the urine arsenic level was significantly higher in the medium- and high-dose groups than in the control group (both P<0.001). Hepatic edema was seen in rats in the low- and medium-dose groups, and hepatic edema, focal hepatic cell necrosis, hyperplasia of bile capillaries and peri-bile capillary endolysis were observed in rats in the high-dose group.@*Conclusions@#Chronic exposure to arsenic may cause morphological alterations of rat hepatic tissues, and the rat hepatic damage aggravates with the dose of exposure to arsenic.

High arsenic tolerance in Brevundimonas aurantiaca PFAB1 from an arsenic-rich Indian hot spring

BACKGROUND Arsenic contamination in the ground water of rural India is a recurrent problem and decon tamination is mostly based on the chemical or physical treatments until now. Microbial bioremediation is eco-friendly, cheap, time-efficient and does not produce any toxic by-products. RESULT In the present study, a high arsenic tolerant bacteria Brevundimonas aurantiaca PFAB1 was iso lated from Panifala hot spring located in West Bengal, India. Previously Panifala was also reported to be an arsenic-rich hot spring. B. aurantiaca PFAB1 exhibited both positive arsenic reductase and arsenite oxidase activity. It was tolerant to arsenite up to 90 mM and arsenate up to 310 mM. Electron microscopy has proved significant changes in cellular micromorphology and stalk appearance under the presence of arsenic in growth medium. Bioaccumulation of arsenic in As (III) treated cells were 0.01% of the total cell weight, while 0.43% in case of As (V) treatment. CONCLUSIONS All experimental lines of evidence prove the uptake/accumulation of arsenic within the bac terial cell. All these features will help in the exploitation of B. aurantiaca PFAB1 as a potent biological weapon to fight arsenic toxicity in the near future

Sodium Arsenite Inhibits Proliferation and Induces Apoptosis of Human Hepatic Cells / 中国生物化学与分子生物学报

Arsenic is a potent toxic heavy metal found in the environment that can causes health problems, including liver disease in humans and animals. Chronic exposure to arsenic remains an environmental health problem worldwide, affecting hundreds of millions of people. Although the oxidative stress and apoptosis induced by arsenic have been confirmed, the underlying mechanism of apoptosis has not been fully elucidated. The purpose of this study is to investigate whether sodium arsenite (SA)induced liver toxicity is related to the regulation of DNA replication and repair pathways. The results of MTT and microscopy showed that SA has an inhibitory effect on the proliferation of human hepatocytes (L02), and this effect is time and concentration dependent. Flow cytometry detected the effects of different concentrations of SA on L02 cells. Compared with the control group, high concentrations of SA significantly affected the L02 cell cycle. In addition, RNA sequencing results showed that the differentially expressed genes in cells after SA treatment were concentrated in the DNA replication process and repair pathways. The effect of SA treatment on the expression of human RECQ DNA helicase and repair genes was further confirmed by Western blot and real-time quantitative PCR. In vitro study showed that SA treatment inhibited cell proliferation, and induced apoptosis as well as DNA damage and cell cycle arrest of human liver cell L02. Collectively, these results indicate that arsenic poisoning is related to the regulation of DNA replication and repair pathways, which provides insight for understanding the molecular mechanism of arsenic poisoning.

Effects of arsenite and MPST over-expressin on GRP78/CHOP endoplasmic reticulum stress pathway in SH-SY5Y cells / 中国药理学通报

Aim To investigate whether endoplasmic reticulum stress is involved in the neurotoxicity of sodi¬um arsenite and clarify whether over-expression of 3-mercaptopyruvate sulfurtransferase (MPST) regulates endoplasmic reticulum stress induced by arsenic. Methods The SH-SY5Y cell line stably expressing the exogenous MPST gene was obtained by constructing the lentiviral vector of MPST gene. The SH-SY5Y cells were randomly divided into six groups, the SR-MPST over-expression group stably expressing the exogenous MPST gene, SH-PEB control group transfected with empty vector, the arsenite treatment group ( NaAs02 group ), TUDC A treatment group ( blocker of endoplasmic reticulum stress ) and TUDC A + NaAs02 group. Western blot was used to examine the protein expression of GRP78 and CHOP after different treatment. Results Although MPST overexpression had no significant effects on the expression of GRP78 and CHOP proteins, NaAs02 could significantly increased the protein levels of GRP78 and CHOP ( P < 0. 01 ) and the up-regulation of GRP78 and CHOP proteins caused by NaAs02 could be blocked by the treatment of TUDC A. In addition, the inhibition by MPST overexpression on the arsenic-induced increase of GRP78 and CHOP proteins (P <0. 01 ) could also be reversed by the TUDC A treatment significantly. Conclusions The GRP78/ CHOP endoplasmic reticulum stress pathway is involved in the neurotoxic damage induced by arsenic; MPST overexpression may decrease arsenic-induced endoplasmic reticulum stress.

Effects of Curcumin on Sodium Arsenite Induced Neoplastic Cell Transformation in Balb/c 3T3 Cells

HIGHLIGHTS Sodium arsenite can cause neoplastic transformation in cells. Curcumin reduced cell viability and increased LDH activity in transformed Balb/c 3T3 cells. Curcumin caused DNA damage in transformed Balb/c 3T3 cells. Curcumin may play a protective role in sodium arsenite-induced toxicity.

Abstract Arsenic is a toxic substance that spreads widely around the environment and accumulates as metalloid in the earth's crust. Arsenic and its derivatives are found in drinking water, nutrients, soil, and air. Exposure to arsenic is associated with lung, blood, skin cancer and various lesions. Curcumin is a polyphenolic compound derived from Curcuma longa (turmeric) rhizome and is one of the main curcuminoids. Curcumin is known to be antioxidant, antibacterial, anti-inflammatory, analgesic effects. This study aimed to investigate the potential of sodium arsenite to transform embryonic fibroblast cells and to evaluate the cytotoxic and genotoxic effects of curcumin in neoplastic transformed cells. Neoplastic cells transformation was induced by sodium arsenite in Balb/c 3T3 cells at the end of 32 days. After transformation assay, the transformed cells were treated with various concentration of curcumin to evaluate cell viability, lactate dehydrogenase activity and DNA damage for 24h. The results revealed that curcumin decreased cell viability and increased the activity of lactate dehydrogenase enzyme in neoplastic transformed Balb/c 3T3 cells. In conclusion, the results demonstrated that curcumin has an anticancer effect on neoplastic transformed Balb/c 3T3 cells by causing DNA damage.

Reusable Enzymatic Strip for Detection of Arsenic

HIGHLIGHTS Arsenic is considered as one of the highly hazardous elements in the environment and a serious carcinogen for the human health. An enzymatic method has been described by using arsenite oxidase for arsenic detection. Residual activity of the immobilized enzyme was 43% of the initial activity after being recycled 10 times.

Abstract Arsenic is considered as one of the highly hazardous elements in the environment and a serious carcinogen for the human health. More attention has taken towards the arsenic due to its presence in ground water in India, China, Bangladesh, Inner Mongolia and several other regions of the world. It's been a challenge to remove arsenic due to the lack of its efficient detection approach in the complicated environmental matrix. The proposed method describes an enzymatic method for arsenic determination using arsenite oxidase, which catalyzes the oxidation of arsenite to arsenate. Hence, a colorimetric PVC strip with immobilized arsenite oxidase has been developed to detect the arsenic concentration and also having potential for the field-testing. The influence of the optimal conditions i.e. pH, temperature, storage stability, and reusability of free and immobilized enzyme were evaluated and compared. The results have shown that the stabilities were significantly enhanced compared with free counterpart. Residual activity of the immobilized enzyme was 43% of the initial activity after being recycled 10 times. We approve that this novel low cost immobilized carrier presents a new approach in large scale applications and expected to act as a model for establishment of indigenous arsenic sensor in miniature form.

Effects of sodium arsenite and arsenic metabolites on the expression of linear and circular RNA of Nup107 in A549 cells / 中国职业医学

OBJECTIVE: To explore the effect of sodium arsenite and arsenic metabolites monomethylarsenic acid(MMA) and dimethylarsenic acid(DMA)on the expression of linear and circularRNAs of nucleoporin 107(Nup107) in human lung adenocarcinoma A549 cells. METHODS: i) The A549 cells in logarithmic phase were treated with 0, 30, 60, 90 μmol/L sodium arsenite for 48 hours. ii)The A549 cells in logarithmic phase were treated with 90 μmol/L sodium arsenite, MMA and DMA for 48 hours, the control group received no treatment. After culturing, the relative expression of linear RNA and circular RNA(circRNA) of Nup107 was detected by real-time quantitative polymerase chain reaction. RESULTS: i) The relative expression of linear RNA of Nup107 decreased and four circRNA isomers such as hsa＿circ＿0003599, hsa＿circ＿0027477, hsa＿circ＿0027478 and hsa＿circ＿0027479 increased with the increase of sodium arsenite dose(all P<0.01), showing a dose-effect relationship. In the 90 μmol/L sodium arsenite stimulated group, the relative expression of linear RNA of Lin-Nup107 decreased, and the four circRNA isomers increased compared with the control group in the A549 cells(all P<0.01). ii) The relative expression of Lin-Nup107 increased in the MMA and DMA stimulated groups and decreased in the sodium arsenite stimulated group compared with the control group in the A549 cells(all P<0.05). The relative expression of Lin-Nup107 decreased in the sodium arsenite stimulated group compared with the MMA and DMA stimulated groups in the A549 cells(all P<0.05). The relative expressions of hsa＿circ＿0003599, hsa＿circ＿0027478, hsa＿circ＿0027479 in the sodium arsenite stimulated group were higher than that in the MMA and DMA stimulated groups as well as the control group(all P<0.05).The relative expressions of hsa＿circ＿0027479 in the DMA stimulated group was lower than that in the control group(P<0.05). CONCLUSION: Sodium arsenite can induce the down-regulation of linear RNA and the up-regulation of circRNA of Nup107 in a dose-dependent manner. The metabolites of arsenic MMA and DMA can induce the overexpression of linear RNA of Nup107, however, they had no obvious effect on the circRNA of Nup107 in A549 cells.

Effect of dictyophora polysaccharide on mitophagy induced by sodium arsenite in L-02 cells / 中华地方病学杂志

Objective:To observe the effect of dictyophora polysaccharide (DIP) on PINK1/Parkin pathway mediated mitophagy induced by sodium arsenite (NaAsO 2) in human hepatocytes (L-02 cells). Methods:The L-02 cells in logarithmic growth phase and in good condition were divided into control group, NaAsO 2 group (10 μmol/L), DIP group (80 μg/ml), DIP + NaAsO 2 group (80 μg/ml DIP + 10 μmol/L NaAsO 2) , N-acetylcysteine (NAC) group (5 mmol/L), and NAC + NaAsO 2 group (5 mmol/L NAC + 10 μmol/L NaAsO 2). Western blotting was used to detect the expression levels of mitophagy related proteins p62, microtubule-associated protein 1 light chain 3 (LC3)Ⅱ/LC3Ⅰ, PINK1, and Parkin. The mitochondrial stucture and autophagosomes were observed by transmission electron microscope, the fluorescent probe method was used to detect the expression level of intracellular reactive oxygen species (ROS). Results:Compared with the control group, the protein expressions of p62, LC3 Ⅱ/LC3 Ⅰ, PINK1, and Parkin in NaAsO 2 group were higher ( P < 0.05); compared with the NaAsO 2 group, the protein expressions of p62, LC3 Ⅱ/LC3 Ⅰ, PINK1 and Parkin were lower in DIP, DIP + NaAsO 2, NAC, and NAC + NaAsO 2 groups ( P <0.05). According to the transmission electron microscope, compared with the control group, the mitochondria of L-02 cells in NaAsO 2 group were significantly damaged and the number of autophagosomes increased. Compared with NaAsO 2 group, the degree of mitochondrial swelling, vacuolar degeneration and the number of autophagosomes decreased in DIP + NaAsO 2 group. Compared with the control group (33 110.00 ± 2 191.28), the intracellular ROS level in NaAsO 2 group was higher (48 000.00 ± 2 395.31, P < 0.05); the level of intracellular ROS in DIP + NaAsO 2 group (38 670.00 ± 2 620.56) was significantly lower than that in NaAsO 2 group( P < 0.05), and there was no significant change compared with the control group ( P > 0.05). Conclusions:NaAsO 2 can induce PINK1/Parkin mediated mitophagy in L-02 cells. DIP can alleviate NaAsO 2 induced mitophagy. DIP may affect PINK1/Parkin mediated mitophagy induced by NaAsO 2 through the regulation of ROS.

Improvement Effects of α-lipoic Acid on Glucose Metabolism Disorder of Insulin Resistant HepG 2 Cells / 中国药房

OBJECTIVE：To study the i mprovement effects of α-lipoic acid on glucose metabolism disorder of insulin resistant HepG2 cells. METHODS ：The effects of 25-1 000 µmol/L α-lipoic acid on survival rate of human hepatoma cell HepG2 were determined by MTT assay so as to determine the concentration of α-lipoic acid. Negative control group ，insulin resistance group （1× 10－7 mol/L insulin ），combination resistance group （30 µmol/L sodium arsenite+ 1×10－8 mol/L insulin ），α-lipoic acid low- concentration，medium-concentration and high-concentration groups were set up. HepG 2 cells were treated with α-lipoic acid for 12 h and then cultured with corresponding concentration of sodium arsenite or/and insulin for 24 h. The glucose oxidase method was used to detect the glucose consumption ，colorimetric method was used to detect hexokinase activity and pyruvate kinase activity ， and anthrone method was used to detect glycogen content. Western blot assay was used to detect the protein expression of GLUT 4， p-GSK3β and GSK3β as well as the ratio of p-Akt/Akt and p-GSK3β/GSK3β. RESULTS：25，50，100 µmol/L α-lipoic acid had no significant effect on the survival rates of HepG 2 cells（P＞0.05），and survival rates of H epG2 cells were higher than 96％，so they were used as the low ，medium and high concentration for follow-up study. Compared with negative control group ，glucose consumption，the activities of hexokinase and pyruvate kinase ，glycogen content ，protein expression of GLUT 4 and p-GSK 3β，the ratio of p-Akt/Akt and p-GSK 3β/GSK3β were decreased significantly in insulin resistance group and combined resistance group， while the protein expression of GSK 3β was increased significantly（P＜0.05）. Compared with combination resistance group ，the glucose consumption （except for α-lipoic acid low- concentration group ），the activities of h exokinase（except for α-lipoic acid low-concentration and medium-concentration groups ） andpyruvate kinase （except for α-lipoic acid low-concentration com and medium-concentration groups ）， glycogen contents ， protein expression of GLUT 4 （except for α-lipoic acid mail：bliang163@163.com low-concentration group ）and p-GSK3β，the ratio of p-Akt/ Akt（except for α-lipoic acid low-concentration and medium-concentration groups ）and p-GSK 3β/GSK3β（except for α-lipoic acid low-concentration groups ）were increased significantly in α-lipoic acid groups ，while protein expression of GSK 3β（except for α-lipoic acid low-concentration and medium-concentration groups ） was decreased significantly （P＜0.05）；glycogen content ， protein expression of GLUT 4 and the ratio of p-GSK 3β/GSK3β in α-lipoic acid high-concentration group as well as the protein expression of p-GSK 3β in α-lipoic acid medium-concentration and high-concentration groups were improved significantly （P＜0.05）. CONCLUSIONS：α-lipoic acid can improve the disorder of glucose metabolism in insulin resistant HepG 2 cells，the mechanism of which may be associated with the increase of glucose consumption ，the activities of glucose metabolism related enzymes and glycogen content ，and expression up-regulation of the phosphorylation levels of Akt and GSK 3β protein，the expression of GLUT 4 and p-GSK 3β proteins，down-regulation of the expression of GSK 3β protein.

Clinical efficacy and safety of low﹣dose decitabine subcutaneous injection combined with arsenicals in treatment of medium﹣and high﹣risk myelodysplastic syndromes / 白血病·淋巴瘤

Objective To explore the clinical efficacy and safety of low﹣dose decitabine subcutaneous injection combined with arsenicals in the treatment of medium﹣ and high﹣risk myelodysplastic syndromes (MDS). Methods Eight cases of medium﹣ and high﹣risk MDS without allogeneic hematopoietic stem cell transplantation in the Affiliated Cancer Hospital of Zhengzhou University and Xinhua Area Hospital of Pingdingshan City from January 2015 to August 2018 were retrospectively analyzed. The patients were given subcutaneous injection of low﹣dose decitabine combined with arsenicals. The specific regimen was as follow:0.1-0.2 mg/kg of decitabine, subcutaneous injection 2 times/week, 4 weeks in total; arsenic injection 10 mg/time or 0.16 mg/kg, intravenous administration, 1 time/d, 4 weeks; compound Huangdai tablets 60 mg/kg per day, 3 times orally. The efficacy and adverse reactions were observed. Results In 8 patients, there were 5 male and 3 female, with an average age of 61.4 years old (44-80 years old) Eleven cases were refractory anemia with excess blasts (RAEB), 6 cases were RAEB﹣2, 1 case was refractory cytopenia with multilineage dysplasia (RCMD) with bone marrow fibrosis (MF). Three of the patients had previously received treatment with decitabine. All patients completed the treatment successfully and no treatment﹣related deaths occurred. By the end of follow﹣up, 2 patients had complete remission, 4 patients had complete bone marrow remission with hematologic improvement, 1 patient had stable disease, and 1 patient had disease progression. For 2 patients who had been treated with decitabine regimen, the regimen of re﹣administered decitabine plus arsenic was still effective. Eight patients had more than level 2 of myelosuppression, except for one patient with intestinal infection due to unclean diet and one patient with mild pulmonary infection. The remaining 6 patients had no associated infection and heart, liver, kidney and other adverse reactions. Conclusion Low﹣dose decitabine subcutaneous injection combined with arsenicals is safe and could be a new treatment for the medium﹣ and high﹣risk MDS.

Effect of sodium arsenite on cell cycle of SH-SY5Y cells and intervention of MPST over-expression / 中国药理学通报

Aim To investigate the effects of sodium arsenite (NaAsO2) on the cell cycle and growth, and the intervention of MPST over-expression in the neural cells. Methods NaAsO2 was used to treat SH-SY5Y neuroblastoma cells for 48 h from the blank control (BC), empty vector control ( transfected with empty vector, NC ) and over-expression group ( lentiviral transfection with MPST,OP). The methods of CCK-8, crystal violet staining,flow cytometry and Western blot were used to examine cell viability,adherent rate,cell cycle and protein expression of p53,CDC25A,CyclinA and CDK2. Results The cell viability and adherent rate significantly decreased after treatment with NaAsO2 for 48 h,which was reversed in OP group (P <0. 01). Meanwhile, NaAsO2 also significantly increased the proportion of S phase cells and p53 protein expression, and down-regulated the protein levels of CDC25A,Cyc-lin A and CDK2 in BC and NC groups ( P < 0. 01), whereas the above changes of protein levels were significantly antagonized in OP group compared with NC group (P < 0. 05, P < 0. 01). Conclusions NaAsO2 inhibits the cell growth by inducing S-phase arrest and over-expression of MPST could reverse the noxious effects caused by NaAsO2 in SH-SY5Y cells.

Draft genome sequence of Chryseobacterium limigenitum SUR2T (LMG 28734T) isolated from dehydrated sludge

ABSTRACT The type strain SUR2 of the novel species Chryseobacterium limigenitum was isolated from a dehydrated sludge of the municipal sewage treatment plant in Dogoše near Maribor in Slovenia. The draft genome, with 60 contigs, 4,697,725 bp, 34.4% of G+C content, was obtained using the Illumina HiSeq 2500-1 platform. Joint Genome Institute Microbial Genome Annotation Pipeline (MGAP v.4) has identified 4322 protein-coding sequences including resistance genes against arsenic and other heavy metals. In addition, a subclass B3 metallo-β-lactamase, which confers resistance to penicillins, cephalosporins and carbapenems, was also present in the genome. The genome sequence provides important information regarding bioremediation potential and pathogenic properties of this newly identified species.

Effects of sodium arsenite exposure on activation and extracellular matrix secretion of human hepatic stellate cells / 中华预防医学杂志

Objective@#To explore the effects of sodium arsenite (NaAsO2) exposure on the activation and extracellular matrix secretion of human hepatic stellate cells, and to provide a theoretical basis for the mechanism study of arsenic induced hepatic fibrosis.@*Methods@#Different doses of NaAsO2 (0.0, 0.1, 1.0, 10.0, 50.0, 100.0 μmol/L) were exposed to human hepatic stellate cell line (Lx-2) for 24, 48 and 72 huors. CCK-8 assay was used to measure cell viability and IC50 of NaAsO2 on Lx-2 was then calculated; According to IC50 results, 0.000, 1.875, 3.750, 7.500, and 15.000 μmol/L of NaAsO2 were exposed to Lx-2 cells for 24 hours, besides, 7.500 μmol/L of NaAsO2 was exposed to Lx-2 cells for 0, 12, 24, 48, and 72 hours, then collected cells and culture supernatant; HSC activation-related protein, including α-smooth muscle actin (α-SMA), and transforming growth factor-β1 (TGF-β1) expression levels were detected by Western blot analysis, the main extracellular matrix including laminin (LN) , hyaluronic acid (HA), collagen Ⅳ (COL-Ⅳ) and procollagen Ⅲ(P Ⅲ NP) secretion level was detected by Elisa assay.@*Results@#CCK-8 assay showed that the cell viability of Lx-2 cells were increased obviously at low doses (≤1.0 μmol/L) of arsenic exposure, especially at 48 and 72 h. In contrast, with the increasing doses of arsenic exposure, the survival rate of Lx-2 cell was decreased gradually, and the survival rate of the high-dose (50, 100 μmol/L) arsenic exposure group at 24, 48 and 72 h were significantly lower than 0.0 μmol/L group, P<0.05. The IC50 of NaAsO2 on Lx-2 cells at 24, 48, 72 h were calculated as 72.75, 48.19 and 29.95 μmol/L, respectively; The expression levels of HSC activation-related protein showed that, after treated with 1.875, 3.750, 7.500, 15.000 μmol/L NaAsO2 for 24 h, α-SMA and TGF-β1 protein level were higher than 0.000 μmol/L group. The increased expression of α-SMA and TGF-β1 protein were most significant in 7.500 μmol/L NaAsO2 group (P<0.05). In addition, the expression levels of α-SMA and TGF-β1 also showed a time-dependent increasing in Lx-2 cells after treated with 7.500 μmol/L NaAsO2 for 0, 12, 24, 48 and 72 h; Elisa assay showed that after treated with 1.875, 3.750, 7.500, 15.000 μmol/L NaAsO2 for 24 h, the secretion levels of HA, LN, COL-Ⅳ and PⅢNP were obvious higher than 0.000 μmol/L group (P<0.05). Moreover, the secretion levels of HA, LN, COL-Ⅳ and P Ⅲ NP also showed a time-dependent increased manner in Lx-2 cells after exposed to 7.500 μmol/L NaAsO2 for 0, 12, 24, 48 and 72 h (P<0.05).@*Conclusion@#NaAsO2 exposure to Lx-2 cells can upregulate the expression level of HSC activation-related proteins, induce its further activation, then increase ECM secretion level.