Benzo[a]pyrene(B[a]P)is a food contaminant toxic for cardiovascular diseases.The nuclear translocation of Arylhydrocarbon receptor(AhR)plays an important role in B[a]P-induced oxidative stress and vascular diseases.We...Benzo[a]pyrene(B[a]P)is a food contaminant toxic for cardiovascular diseases.The nuclear translocation of Arylhydrocarbon receptor(AhR)plays an important role in B[a]P-induced oxidative stress and vascular diseases.We confi rmed that B[a]P promoted ROS production in vascular smooth muscle cells(VSMCs)in vitro and in vivo,associated with the nuclear translocation of AhR.It is known that phosphorylation inhibits while dephosphorylation of AhR promotes nuclear translocation of AhR.However,from the posttranslational modifi cation level,the mechanism by which B[a]P activates and regulates the nuclear translocation of AhR is unclear.Co-immunoprecipitation results showed that cytoplasmic AhR was phosphorylated before B[a]P stimulation,and switched to O-GlcNAcylation upon B[a]P 1-h stimulation in VSMCs,suggesting there may be a competitively inhibitory relationship between O-GlcNAcylation and phosphorylation of AhR.Next,siRNAs of O-linked N-acetylglucosamine transferase(OGT),O-GlcNAcase(OGA)and OGA inhibitor PUGNAc were used.SiOGT blocks but siOGA and PUGNAc promote B[a]P-dependent AhR nuclear translocation and oxidative stress.Ser11 may be the competitive binding site for phosphorylation and O-GlcNAcylation of AhR.Phosphorylation-mimic variant inhibits but O-GlcNAcylation of AhR promotes AhR nuclear translocation and oxidative stress.Our fi ndings highlight a new perspective for AhR nuclear translocation regulated by the competitive modifi cation between phosphorylation and O-GlcNAcylation.展开更多
AIM To study the inhibitory effects of VES( RRR-α-tocopheryl Succinate, VES ), aderivative of natural Vitamin E, on benzo (a)pyrene (B (a) P)-induced forestomach tumor infemale mice.METHODS The model of B (a)P-induce...AIM To study the inhibitory effects of VES( RRR-α-tocopheryl Succinate, VES ), aderivative of natural Vitamin E, on benzo (a)pyrene (B (a) P)-induced forestomach tumor infemale mice.METHODS The model of B (a)P-inducedforestomach tumor was established according tothe methods of Wattenberg with slightmodifications. One hundred and eighty femalemice (6 weeks old) were divided into six groupsequally; negative control (Succinic acid),vehicle control ( Succinate + B (a) P), positivecontrol(B(a) P), high VES(2.5g/kg. b. w + B(a)P), Iow VES(1 .25 g/kg. b. w + B(a) P) ig as wellas VES by ip (20 mg/kg, b. w + B(a) P). Exceptthe negative control group, the mice wereadministrated with B(a)P ig. and correspondingtreatments for 4 weeks to study the anti-carcinogenetic effect of VES during the initiationperiod. The experiment lasted 29 weeks, inwhich the inhibitory effects of VES both ontumor incidence and tumor size were tested.RESULTS The models of B (a)P-inducedforestomach tumor in female mice wereestablished successfully. Some werecauliflower-like, others looked like papilla, evena few were formed into the ulcer cavities. VES at1.25 g/kg. b. w, 2.5 g/kg. b.w. by ig and 20 mg/kg. b. w. via ip could decrease the number oftumors per mouse (1.7 ± 0. 41, 1.6 ± 0.34 and 1.1±0.43), being lower than that of B(a)P group(5.4 ± 0.32, P<0.05). The tumor incidence wasinhibited by 18.2%, 23.1% and 50.0%. VES at1.25g/kg.b.w., 2.5 g/ kg.b.w. by ig and20 mg/kg. b.w. via ip reduced the total volumeof tumors per mouse (54.8 ± 8.84, 28.4 ± 8.32and 23.9± 16.05), being significantly lower thanthat of B(a)P group (150.2±20.93, P<0.01).The inhibitory rates were 63.5%, 81.1% and84.1%, respectively.CONCLUSION VES has inhibitory effects on B(a) P-induced forestomach carcinogenesis infemale mice, especially by ip and it may be apotential anti-cancer agent in vivo.展开更多
Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons (PAHs) were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a...Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons (PAHs) were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene (BaP). The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10--200 mg/kg. The scanning electronic microscope (SEM) analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP.展开更多
The rates of photodegradation and photocatalysis of benzo [a]pyrene (BaP) on soil surfaces under UV light have been studied. Different parameters such as temperature, soil particle sizes, and soil depth responsible ...The rates of photodegradation and photocatalysis of benzo [a]pyrene (BaP) on soil surfaces under UV light have been studied. Different parameters such as temperature, soil particle sizes, and soil depth responsible for photodegradation, catalyst loads and wavelength of UV irradiation blamed for photocatalysis have been monitored. The results obtained indicated that BaP photodegradation follows pseudo-first-order kinetics. BaP photodegradation was the fastest at 30℃ . The rates of BaP photodegradation at different soil particle size followed the order: less than 1 mm〉less than 0.45 mm〉less than 0.25 mm. When the soil depth increased from 1 mm to 4 ram, the half-life increased from 13.23 d to 17.73 d. The additions of TiO2 or Fe2O3 accelerated the photodegradation of BaP, and the photocatalysis of BaP follows pseudo-first-order kinetics. Changes in catalyst loads of TiO2 (0.5%, 1%, 2%, and 3% (wt)) or Fe203 (2%, 5%, 7%, and 10% (wt)) did not significantly affect the degradation rates. Both BaP photocatalysis in the presence of TiO2 and Fe2O3 were the fastest at 254 nm UV irradiation.展开更多
It has been reported that there is an interaction between Benzo[a]pyrene (BaP), a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin (TBT), an organometal used as an antifouling biocide. This...It has been reported that there is an interaction between Benzo[a]pyrene (BaP), a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin (TBT), an organometal used as an antifouling biocide. This study was therefore designed to examine the potential in vivo influence of BaP, TBT and their mixture on splenic antioxidant defense systems of Sebastiscus marmoratus. The fish were exposed to water containing environmentally relevant concentrations of BaP, TBT and their mixture. Spleens were collected for biochemical analysis after exposure for 7, 25, 50 d and after recovery for 7, 20 d. Cotreatment with BaP and TBT for 7 d potentiated the induction of glutathione peroxidase (GPx) activity by BaP or TBT alone. The cotreatment for 25 and 50 d resulted in inhibition of GPx activity, which was similar to the effect of TBT. Splenic glutathione S-transferase (GST) activities were significantly elevated in S. marmoratus exposed to BaP starting from 7 d and remained high up to 25 d. However, no further activity change was found with prolonged exposure. Cotreatment of BaP and TBT primarily inhibited the GST activity, which was similar to the effect of TBT. Cotreatment with BaP and TBT for 25 or 50 d potentiated the depletion of GSH (glutathione) by BaP or TBT alone. MDA (malondialdehyde) contents in spleen of S. marmoratus were not significantly altered compared with the control during the test period. Spleen, as an immune organ, is sensitive to exposure of BaP or TBT. It should have an effective mechanism to counteract oxidative damage. Antioxidative defense systems in spleen of S. marmoratus should be considered as potential biomarkers. Short-term exposure of BaP or TBT could result in induction of antioxidant defense system. A significant decrease of these indices, such as GSH, GST, GPx might indicate more severe contamination.展开更多
A bacterial strain BAP5 with a relatively high degradation ability of benzo[a]pyrene (BaP) was isolated from marine sediments of Xiamen Western Sea, China and identified as Ochrobactrum sp. according to 16S rRNA gen...A bacterial strain BAP5 with a relatively high degradation ability of benzo[a]pyrene (BaP) was isolated from marine sediments of Xiamen Western Sea, China and identified as Ochrobactrum sp. according to 16S rRNA gene sequence as well as Biolog microbial identification system. Strain BAP5 could grow in mineral salt medium with 50 mg/L of BaP and degrade about 20% BaP after 30 d of incubation. Ochrobactrum sp. BAP5 was able to utilize other polycyclic aromatic hydrocarbons (PAHs) (such as phenanthrene, pyrene and fluoranthene) as the sole carbon source and energy source, suggesting its potential application in PAHs bioremediation. The profile of total soluble protein from Ochrobactrum sp. BAP5 was also investigated. Some over- and special-expressed proteins of strain BAP5 when incubated with the presence of BaP were detected by two-dimensional polyacrylamide gel electrophoresis, and found to be related with PAHs metabolism, DNA translation, and energy production based on peptide fingerprint analysis through matrix-assisted laser desorption/ionization-time of flight mass spectrometry.展开更多
Objective Benzo[a]pyrene (B[a]P), a ubiquitous environmental pollutant, is a potent procarcinogen and mutagen that can elicit tumors, leading to malignancy. Heat shock proteins (Hsp) have been shown to protect cells a...Objective Benzo[a]pyrene (B[a]P), a ubiquitous environmental pollutant, is a potent procarcinogen and mutagen that can elicit tumors, leading to malignancy. Heat shock proteins (Hsp) have been shown to protect cells against damages caused by various stresses including exposure to numerous chemicals. Whether Hsps, or more specifically Hsp70, are involved in repair of B[a]P-induced DNA damage is currently unknown. Methods We assessed the potential role of the inducible form of Hsp70 in B[a]P-induced DNA damage of human embryonic lung (HEL) cells using immunoblot and the comet assay (i.e., the single cell gel electrophoresis assay). Results Exposure to B[a]P induced a dose-dependent decrease in the level of Hsp70, but a dose-dependent +-increase in DNA damage both in untreated (control) HEL cells and in cells preconditioned by a heat treatment. Heat preconditioning prior to B[a]P exposure potentiated the effect of B[a]P at a low dose (10 μmol/L), but appeared to be protective at higher doses. There was a negative correlation between Hsp70 level and DNA damage in the non-preheated as well as in the preconditioned cells. Conclusion These data suggest that exposure of HEL cells to B[a]P may induce a dose-dependent reduction in the levels of the inducible Hsp70. The detailed mechanisms for the reduction of Hsp70 levels by B[a]P and the role of Hsp70 in DNA damage under different concentrations of B[a]P remains to be determined.展开更多
Tributyltin(TBT), an organometal used as an antifouling biocide, has been reported to induce masculinization of fish. Benzo [a]pyrene (BaP), a widespread carcinogenic polycyclic aromatic hydrocarbon, has been repo...Tributyltin(TBT), an organometal used as an antifouling biocide, has been reported to induce masculinization of fish. Benzo [a]pyrene (BaP), a widespread carcinogenic polycyclic aromatic hydrocarbon, has been reported that its microsomal metabolites can produce an estrogenic response when tested in vitro. This study was therefore designed to examine the potential in vivo influence of TBT, BaP and their mixture on sex hormone levels in serum of Sebastiscus marmoratus, which were given 2 separate intraperitoneally (ip) injections(a single injection every 7 d) of TBT(0.5, 1, 5 and 10 mg/kg), BaP(0.5, 1, 5 and 10 mg/kg), or both in combination(0.5, 1, 5 and 10 mg/kg); control fish received olive oil vehicle only. Six days after the 2nd injection, serum samples were collected and analyzed for sex hormone levels and alkali labile protein phosphorus (ALPP), which is related to the yolk precursor protein vitellogenin. The pollutants at all doses significantly reduced serum testosterone, estradiol and ALPP content after 2 injections compared with the corresponding controls. The reduction of the estradiol levels should be response for the decrease of the vitellogenin levels. The results in the present study suggested that aromatase seems not the major target acted by TBT and BaP in fish. This study demonstrated that TBT or BaP exposure both inhibit the reproductive potential in female Sebastiscus marmoratus. Combined effect of TBT and BaP on the serum testosterone, estradiol and ALPP was not antagonism from the anticipation.展开更多
Two compounds,3-oxo-N-o-tolylbenzo[d]isothiazole-2(3H)-carboxamide (1) and N-(2-methoxyphenyl)-3-oxobenzo[d]isothiazole-2(3H)-carboxamide (2),were synthesized from the initial compound benzo[d]isothiazol-3...Two compounds,3-oxo-N-o-tolylbenzo[d]isothiazole-2(3H)-carboxamide (1) and N-(2-methoxyphenyl)-3-oxobenzo[d]isothiazole-2(3H)-carboxamide (2),were synthesized from the initial compound benzo[d]isothiazol-3(2H)-one (BIT) and characterized by 1 H NMR,IR and elemental analysis,respectively.The single crystals of compounds 1 and 2 were obtained and determined by X-ray diffraction analysis.The preliminary results of biological activity experiment show that some of the title compounds exhibited a favorable antimicrobial activity.展开更多
The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4(3H)-one (C16H18N2O3, Mr = 286.32) has been prepared and determined by singlecrystal X-ray diffraction. The crystal is ...The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4(3H)-one (C16H18N2O3, Mr = 286.32) has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167(14), b = 13.113(1), c = 8.378(1) A, β = 98.992(2)^o, V = 1488.4(3) A^3, Z = 4, Dc = 1.278, F(000) = 608, μ = 0.089 mm^-1, MoKa radiation (2 = 0.71073), R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar.展开更多
The effects on hepatic EROD (7-ethoxyresorufin O-deethylase) in Mugil so-iuy exposedto benzo(a)pyrene (BaP), pyrene and their mixtures of equal concentration were investigated, at concentrations of 0.1, 1.0, 5.0, 10.0...The effects on hepatic EROD (7-ethoxyresorufin O-deethylase) in Mugil so-iuy exposedto benzo(a)pyrene (BaP), pyrene and their mixtures of equal concentration were investigated, at concentrations of 0.1, 1.0, 5.0, 10.0, 50.0μg/dm3, in experimental condition. Time-effects and dose-response of the biochemical indexs were observed. The results showed that the hepatic EROD activities were induced by the exposure of BaP, pyrene and their mixtures at high concentration. Dose-response connections were that the hepatic EROD activities were elevated with increasing concentration of the pollutants. The combined effect of BaP and pyrene at 1:1 concentration ratio on hepatic EROD activity was antagonism.展开更多
The distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naptho-furans in source rocks from Niger Delta basin,Nigeria,were investigated by Rock-Eval pyrolysis and gas chro-matogra...The distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naptho-furans in source rocks from Niger Delta basin,Nigeria,were investigated by Rock-Eval pyrolysis and gas chro-matography--mass spectrometry(GC--MS).The data obtained from the source rocks evaluation showed that the rock samples contained type 1/III kerogen capable of generating oil and gas and were within immature to early mature stage.The relative abundance of the Cor,C1-and C2-dibenzofurans range from 1.75%to 29.82%,27.60%to 40.52%and 29.66%to 6889%,respectively.The diben-zofurans were dominated by C-dibenzofurans.Among the C1-dibenzofurans,2-+3-methyldibenzofuran was the most abundant in the rock samples while 1-methy ldibenzofuran appeared to be the least.The relative abundance of benzo[b]naphtho[1,2-d]furan(1,2]BNF),benzo[b]naph-tha[2,1-d]furan(2.1]BNF)and benzo[b]naphtha[2,3-d]fu-ran([2.3]BNF)in the rock extracts range from 12.01%to 52.58%,32.61%to 75.219%and 10.27%to 52.43%.The wide range of values recorded for the three isomers of benzo[b lnapthofurans in the samples suggest source rocks formed from mixed organic matter.Among the pheny ldibenzofuran isomers,4-pheny ldibenzofuran was the most abundant while 1-phenyldibenzofuran was the least.Phenyldibenzofuran ratio-1(PhFR-1)and pheny ldibenzofuran ratio-2(PhFR-2)values range from 0.13 to 1.20 and 0.11 to 2.11,respectively.The resuls showed that the relative abundance of PhFR-1 and PhFR-2 increase gradually with increasing burial depth and maturity(VRo≤0.77%,MPI-1≤0.62.Tmax s 443℃),and have a good correlations with calculated vitrinite reflectance.MPI-I and maximum Temperature(Tmax)-This range of values suggested immature to early mature source rocks.The source rocks were found to have shale and coul lithologics and deposited in a lacustrine/fuvial deltaic settings within immature to early mature stages based on the distribution of dibenzofurans,pheny ldiben-zofurans and benzo[b]naphthofurans in the source rocks.This study showed that dibenzof urans,phenyldibenzofu-rans and benzo[b]naphthofurans were ffcive in deter-mining the origin,depositional environment and thermal maturity of source rocks in Niger Delta basin,Nigeria.展开更多
Objective To investigate the roles of the cyclin D1/CDK4 and E2F-1/4 pathways and compare their work patterns in cell cycle changes induced by different doses of B[a]E Methods Human embryo lung fibroblasts (HELFs) w...Objective To investigate the roles of the cyclin D1/CDK4 and E2F-1/4 pathways and compare their work patterns in cell cycle changes induced by different doses of B[a]E Methods Human embryo lung fibroblasts (HELFs) were treated with 2 μmol/L or 100 μmol/L B[a]P which were provided with some characteristics of transformed cells (T-HELFs). Cyclin D l, CDK4 and E2F-1/4 expressions were determined by Western blotting. Flow cytometry was used to detect the distribution of cell cycle. Results After B[a]P treatment, the proportion of the first gap (G 1) phase cells decreased. CDK4 and E2F-4 expression did not change significantly. In 2 μmol/L treated cells, a marked overexpression of cyclin D1 and E2F-1 was observed. However, in T-HELFs overexpression was limited to cyclin D1 only, and no overexpression of E2F-1 was observed. The decreases of G1 phase in response to B[a]P treatment were blocked in antisense cyclin D1 and antisense CDK4 transfected HELFs (A-D1 and A-K4) and T-HELFs (T-A-D1 and T-A-K4). After 2 μmol/L B[a]P treatment, overexpression of E2F-1 was attenuated in A-D1, and E2F-4 expression was decreased significantly in A-K4. In T-A-D1 and T-A-K4, E2F-4 expression was increased significantly, compared with T-HELFs. The E2F-1 expression remained unchanged in T-A-D1 and T-A-K4. Condusions Cyclin DI/CDK4-E2F-1/4 pathways work in different patterns in response to low dose and high dose B[a]P treatment. In HELFs treated with 2 μmol/L B[a]P, cyclin D1 positively regulates the E2F-1 expression while CDK4 negatively regulates the E2F-4 expression; however, in HELFs treated with 100 μmol/L B[a]P, both cyclin D1 and CDK4 negatively regulate the E2F-4 expression.展开更多
Objective The present study aimed to test whether exposure to benzo(a)pyrene [B(a)P] affects spatial learning and short-term memory by modulating the expression of the Gria1 and Grin2a glutamate receptor subunit g...Objective The present study aimed to test whether exposure to benzo(a)pyrene [B(a)P] affects spatial learning and short-term memory by modulating the expression of the Gria1 and Grin2a glutamate receptor subunit genes in the hippocampus.Methods Thirty-six 21-24-day-old,male rats were randomly assigned into high-,medium-,and low-dose toxin exposure groups (6.25,2.5,and 1 mg/kg,respectively) and a control group,each containing nine rats.The behavioral performance of adult rats exposed to sub-chronic administration of B(a)P was monitored by learning and memory tests (Morris water maze).Real-time PCR assays were used to quantify Gria1 and Grin2a gene expression in the hippocampus.Results At medium and high doses,B(a)P impaired spatial learning performance.The crossing-platform-location frequency and the time spent swimming in the platform area,which both relate to short-term memory,were significantly decreased in B(a)P-treated rats compared with controls.The level of Gria1 mRNA increased 2.6-5.9-fold,and the level of Grin2a mRNA increased 10-14.5-fold,with a greater fold increase associated with higher doses of B(a)P.Conclusion We demonstrated that sub-chronic administration of B(a)P inhibits spatial learning and short-term memory,and increases Gria1 and Grin2a expression in the hippocampus.This suggests a relationship of B(a)P exposure levels with Gria1 and Grin2a expression and impairment of short-term and spatial memory.展开更多
In this experiment lung carcinoma was induced by crocidolite plus benzo(a)pyrene in rat. From the cancer models, we observcd that the incidcnce (16.0%) of lung carcinomas was lowel, and the survival time (376 days) of...In this experiment lung carcinoma was induced by crocidolite plus benzo(a)pyrene in rat. From the cancer models, we observcd that the incidcnce (16.0%) of lung carcinomas was lowel, and the survival time (376 days) of the first case of carcinoma and the mean survival time (758 days) of the rats with carcinoma were higher in the group of rats drinking 2% green tea extract for life than in the positive group (without drinking green tea extract). The mortality ratio (0.5047) was smaller in the cxperimental group than in the positive control group, and the survival curve of the experimental group significantly raised up, in comparison with the positive group.展开更多
In order to investigate the mechanism of benzo[a]pyrene uptake by a filamentous fungus Fusarium solani, a biochemical characterization of its concentrated culture filtrate has been conducted. The preparation contained...In order to investigate the mechanism of benzo[a]pyrene uptake by a filamentous fungus Fusarium solani, a biochemical characterization of its concentrated culture filtrate has been conducted. The preparation contained approximately (w/w): 50% of total carbohydrate, 6.5% of uronic acid and 6% protein, as determined by colorimetric tests. Gel filtration and anion-exchange chromatographic profiles indicated that the main product of the culture filtrate was a glycoprotein, which contained mannose, glucose and galactose in an approximate molar ratio of 1.5: 0.8: 1. The polysaccharide fraction of the culture filtrate was prepared by treatment with proteinase K, followed by gel-filtration chromatography. Its chemical structure was studied by methylation analysis, gas-liquid chromatography-mass spectrometry (GC-MS) and Nuclear Magnetic Resonance spectroscopy (NMR). The major carbohydrate was a polymer of β-(1 → 6)-linked galactofuranose units fully branched at positions O-2 by single residues of α-glucopyranose. The Fusarium concentrated culture filtrate increased 4-fold the BaP solubilization in comparison with its aqueous solubility and suggested that the carbohydrate present in this filtrate should probably be involved in this enhancement. Our findings point out the potential role of fungal glycoproteins in PAH microbial bioavaibility, an important step for PAH biodegradation.展开更多
Objective:To identify the alleralinn of the membrane polenlial and llie effect of carolenoid extracts from Chlorococcum hnmicola(C.humicola) on membrane hound ATPases and lipid peroxidation.Methods:The lolal carotenoi...Objective:To identify the alleralinn of the membrane polenlial and llie effect of carolenoid extracts from Chlorococcum hnmicola(C.humicola) on membrane hound ATPases and lipid peroxidation.Methods:The lolal carotenoids were extracted from C.humicola.Four groups of Swiss albino mice were treated as control,Benzo(a)pyrene[B(a)P],total carotenoids,B(a)P+ total caralenoids respectively for a period of 60 days.Membrane lipid peroxidation and ATPases(Total ATPases,Ca^(2+)-ATPases.Mg^(2+)-ATPases.Na^+K^+- ATPasei were determined in lung,liver and erythrocyte samples.Results:The activity of lolal ATPase was found to be significantly increased in the B(a)P treated liver and lung tissue.Erythrocyte membrane also showed higher ATPase activity which was significantly reverted on total carolenoid treatment.Conclusions: It can be concluded that the changes in membrane potential favour the functional deterioration of physiological system.The overall findings demonstrates that the animals post treated with carolenoid extract from C.humicola may maintains the alterations in membrane bound ATPase and lipid peroxidation in tissues against the carcinogenic chemical and hence aid in establishing the membrane potential action.Then-fore C.humicola can be further extended to exploits its possible application for various health benefits as neulraceulicals and food additives.展开更多
Objective To study the benzo(a)pyrene(B[a]P)-induced mRNA expression of aromatic hydrocarbon receptor(AHR)and cytochrome P4501A1(CYP1A1)genes in rat liver.Methods Rats were injected intraperitoneally with 5,10 and 15m...Objective To study the benzo(a)pyrene(B[a]P)-induced mRNA expression of aromatic hydrocarbon receptor(AHR)and cytochrome P4501A1(CYP1A1)genes in rat liver.Methods Rats were injected intraperitoneally with 5,10 and 15mg/kg of B[a]P.The total RNAs were extracted from rat livers by RNA purification kit,and the mRNA expression of AHR and CYP1A1 genes was determined by reverse transcription polymerase chain reaction(RT-PCR).β-actin was used as the internal control.The mRNA expression of both AHR and CYP1A1 genes was measured at indicated time points(24,48 and 72h)after B[a]P treatment at three different concentrations(5,10 and 15mg/kg).Results The mRNA expression of AHR gene increased in a time-dependent manner at the concentration of 10mg/kg but not at 5 and 15mg/kg of B[a]P.The mRNA expression of CYP1A1 gene differed significantly at 48h and 24h in rat livers treated with 10 and 15mg/kg dosage of B[a]P.The mRNA expression of AHR and CYP1A1 genes increased with B[a]P treatment in a concentration-dependent manner.The time-dependent increase in mRNA expression was shown by AHR but not by CYP1A1 gene with B[a]P(10mg/kg)treatment.Conclusion This study demonstrates that toxic B[a]P increases the mRNA expression of both AHR and CYP1A1 genes in vivo,suggesting that B[a]P may play a role in cancer genesis by this way.展开更多
The concentrations of reduced-glutathione ( GSH) in liver and ovary of Boleophthalmus pectinirostris are quantified. The concentrations of GSH in the ovary are much higher than that of GSH in the liver(nearly 3 times ...The concentrations of reduced-glutathione ( GSH) in liver and ovary of Boleophthalmus pectinirostris are quantified. The concentrations of GSH in the ovary are much higher than that of GSH in the liver(nearly 3 times of the liver). The study also investigates the changes of GSH contents in the two organs while the fishes were exposed to benzo(a)pyrene(BaP) at concentrations of 0, 0.05, 0.2 and 0.5 mg/L respectively for up to a week. The concentrations of GSH in the liver of BaP-exposed fish increased significantly with dose, whereas the concentrations of GSH in the ovary decreased significantly compared to controls. The results suggested that both the liver and the ovary are the primary organ in BaP metabolism, and that the changes of GSH levels may represent an adaptive response or toxic effect to Bap exposure.展开更多
In this study, the RNA sequencing was used to describe the response of Nannochloropsis oceanica, a marine microalga, to benzo[a]pyrene(BaP), a polycyclic aromatic hydrocarbon, in order to elucidate the metabolic pathw...In this study, the RNA sequencing was used to describe the response of Nannochloropsis oceanica, a marine microalga, to benzo[a]pyrene(BaP), a polycyclic aromatic hydrocarbon, in order to elucidate the metabolic pathways(or processes) involved in microalgal response to this stubborn pollutant. N. oceanica was exposed to BaP at a concentration of 90 μg L^-1 for 72 h, and its transcriptome was sequenced through the Illumina HiSeq^TM 2500 platform. This concentration of BaP was selected as it is the lowest for modeling the most appropriate growth inhibition of N. oceanica for transcriptomic analysis. We found that N. oceanica responds to BaP through degrading proteins and repairing DNA damaged by BaP. In addition, superoxide dismutase(SOD) strengthened its performance by increasing its transcript abundance. The physiological mechanism underlining the response of N. oceanica to BaP as revealed by transcriptomic analysis was consistent with the biochemical insights documented previously.展开更多
基金supported by the National Key Research Project of China(2022YFF1100300)National Natural Science Foundation of China(32272328)+5 种基金Natural Science Foundation of Hebei Province(B2022321001)Major Public Welfare Projects in Henan Province(201300110200)National Key Research Project of Hebei Province(20375502D)National Key Research Project of Hebei Province(H2021206427)University Science and Technology Research Project of Hebei Province(QN2017107)Postdoctoral Research Funds of Hebei Medical University(307050100163759).
文摘Benzo[a]pyrene(B[a]P)is a food contaminant toxic for cardiovascular diseases.The nuclear translocation of Arylhydrocarbon receptor(AhR)plays an important role in B[a]P-induced oxidative stress and vascular diseases.We confi rmed that B[a]P promoted ROS production in vascular smooth muscle cells(VSMCs)in vitro and in vivo,associated with the nuclear translocation of AhR.It is known that phosphorylation inhibits while dephosphorylation of AhR promotes nuclear translocation of AhR.However,from the posttranslational modifi cation level,the mechanism by which B[a]P activates and regulates the nuclear translocation of AhR is unclear.Co-immunoprecipitation results showed that cytoplasmic AhR was phosphorylated before B[a]P stimulation,and switched to O-GlcNAcylation upon B[a]P 1-h stimulation in VSMCs,suggesting there may be a competitively inhibitory relationship between O-GlcNAcylation and phosphorylation of AhR.Next,siRNAs of O-linked N-acetylglucosamine transferase(OGT),O-GlcNAcase(OGA)and OGA inhibitor PUGNAc were used.SiOGT blocks but siOGA and PUGNAc promote B[a]P-dependent AhR nuclear translocation and oxidative stress.Ser11 may be the competitive binding site for phosphorylation and O-GlcNAcylation of AhR.Phosphorylation-mimic variant inhibits but O-GlcNAcylation of AhR promotes AhR nuclear translocation and oxidative stress.Our fi ndings highlight a new perspective for AhR nuclear translocation regulated by the competitive modifi cation between phosphorylation and O-GlcNAcylation.
基金Project Supported by National Natural Science Foundation of China, No. 39870662
文摘AIM To study the inhibitory effects of VES( RRR-α-tocopheryl Succinate, VES ), aderivative of natural Vitamin E, on benzo (a)pyrene (B (a) P)-induced forestomach tumor infemale mice.METHODS The model of B (a)P-inducedforestomach tumor was established according tothe methods of Wattenberg with slightmodifications. One hundred and eighty femalemice (6 weeks old) were divided into six groupsequally; negative control (Succinic acid),vehicle control ( Succinate + B (a) P), positivecontrol(B(a) P), high VES(2.5g/kg. b. w + B(a)P), Iow VES(1 .25 g/kg. b. w + B(a) P) ig as wellas VES by ip (20 mg/kg, b. w + B(a) P). Exceptthe negative control group, the mice wereadministrated with B(a)P ig. and correspondingtreatments for 4 weeks to study the anti-carcinogenetic effect of VES during the initiationperiod. The experiment lasted 29 weeks, inwhich the inhibitory effects of VES both ontumor incidence and tumor size were tested.RESULTS The models of B (a)P-inducedforestomach tumor in female mice wereestablished successfully. Some werecauliflower-like, others looked like papilla, evena few were formed into the ulcer cavities. VES at1.25 g/kg. b. w, 2.5 g/kg. b.w. by ig and 20 mg/kg. b. w. via ip could decrease the number oftumors per mouse (1.7 ± 0. 41, 1.6 ± 0.34 and 1.1±0.43), being lower than that of B(a)P group(5.4 ± 0.32, P<0.05). The tumor incidence wasinhibited by 18.2%, 23.1% and 50.0%. VES at1.25g/kg.b.w., 2.5 g/ kg.b.w. by ig and20 mg/kg. b.w. via ip reduced the total volumeof tumors per mouse (54.8 ± 8.84, 28.4 ± 8.32and 23.9± 16.05), being significantly lower thanthat of B(a)P group (150.2±20.93, P<0.01).The inhibitory rates were 63.5%, 81.1% and84.1%, respectively.CONCLUSION VES has inhibitory effects on B(a) P-induced forestomach carcinogenesis infemale mice, especially by ip and it may be apotential anti-cancer agent in vivo.
基金The National Basic Research Program (973) of China (No. 2004CB418506)the National Natural Science Foundation of China (No.20337010) the Hi-Tech Research and Development Program (863) of China (No. 2004AA649060)
文摘Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons (PAHs) were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene (BaP). The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10--200 mg/kg. The scanning electronic microscope (SEM) analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP.
基金The National Basic Research Program (973) of China (No. 2004CB418506)the National Natural Science Foundation of China (No.20337010) the Hi-Tech Research and Development Program (863) of China (No. 2004AA649060)
文摘The rates of photodegradation and photocatalysis of benzo [a]pyrene (BaP) on soil surfaces under UV light have been studied. Different parameters such as temperature, soil particle sizes, and soil depth responsible for photodegradation, catalyst loads and wavelength of UV irradiation blamed for photocatalysis have been monitored. The results obtained indicated that BaP photodegradation follows pseudo-first-order kinetics. BaP photodegradation was the fastest at 30℃ . The rates of BaP photodegradation at different soil particle size followed the order: less than 1 mm〉less than 0.45 mm〉less than 0.25 mm. When the soil depth increased from 1 mm to 4 ram, the half-life increased from 13.23 d to 17.73 d. The additions of TiO2 or Fe2O3 accelerated the photodegradation of BaP, and the photocatalysis of BaP follows pseudo-first-order kinetics. Changes in catalyst loads of TiO2 (0.5%, 1%, 2%, and 3% (wt)) or Fe203 (2%, 5%, 7%, and 10% (wt)) did not significantly affect the degradation rates. Both BaP photocatalysis in the presence of TiO2 and Fe2O3 were the fastest at 254 nm UV irradiation.
基金Project supported by the National Natural Science Foundation of China(No.20447001, 40476049)the Natural Science Foundation of Fujian Province of China(No. D0410007).
文摘It has been reported that there is an interaction between Benzo[a]pyrene (BaP), a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin (TBT), an organometal used as an antifouling biocide. This study was therefore designed to examine the potential in vivo influence of BaP, TBT and their mixture on splenic antioxidant defense systems of Sebastiscus marmoratus. The fish were exposed to water containing environmentally relevant concentrations of BaP, TBT and their mixture. Spleens were collected for biochemical analysis after exposure for 7, 25, 50 d and after recovery for 7, 20 d. Cotreatment with BaP and TBT for 7 d potentiated the induction of glutathione peroxidase (GPx) activity by BaP or TBT alone. The cotreatment for 25 and 50 d resulted in inhibition of GPx activity, which was similar to the effect of TBT. Splenic glutathione S-transferase (GST) activities were significantly elevated in S. marmoratus exposed to BaP starting from 7 d and remained high up to 25 d. However, no further activity change was found with prolonged exposure. Cotreatment of BaP and TBT primarily inhibited the GST activity, which was similar to the effect of TBT. Cotreatment with BaP and TBT for 25 or 50 d potentiated the depletion of GSH (glutathione) by BaP or TBT alone. MDA (malondialdehyde) contents in spleen of S. marmoratus were not significantly altered compared with the control during the test period. Spleen, as an immune organ, is sensitive to exposure of BaP or TBT. It should have an effective mechanism to counteract oxidative damage. Antioxidative defense systems in spleen of S. marmoratus should be considered as potential biomarkers. Short-term exposure of BaP or TBT could result in induction of antioxidant defense system. A significant decrease of these indices, such as GSH, GST, GPx might indicate more severe contamination.
基金supported by the National Natural Sci-ence Foundation of China (No 40206015, 30970106)the Fork Ying Tong Education Foundation (No 94002) the Science and Technology Project of Guangdong Province,China (No 2006A36502001, 2007A032600003)
文摘A bacterial strain BAP5 with a relatively high degradation ability of benzo[a]pyrene (BaP) was isolated from marine sediments of Xiamen Western Sea, China and identified as Ochrobactrum sp. according to 16S rRNA gene sequence as well as Biolog microbial identification system. Strain BAP5 could grow in mineral salt medium with 50 mg/L of BaP and degrade about 20% BaP after 30 d of incubation. Ochrobactrum sp. BAP5 was able to utilize other polycyclic aromatic hydrocarbons (PAHs) (such as phenanthrene, pyrene and fluoranthene) as the sole carbon source and energy source, suggesting its potential application in PAHs bioremediation. The profile of total soluble protein from Ochrobactrum sp. BAP5 was also investigated. Some over- and special-expressed proteins of strain BAP5 when incubated with the presence of BaP were detected by two-dimensional polyacrylamide gel electrophoresis, and found to be related with PAHs metabolism, DNA translation, and energy production based on peptide fingerprint analysis through matrix-assisted laser desorption/ionization-time of flight mass spectrometry.
基金This work was supported by grants from the National Natural Science Foundation of China (NNSFC) and the National Key Basic Research and Development Program to WT (2002 CB512905) by a collaborative exchange grant between the NNSFC and the CIHR of Canad
文摘Objective Benzo[a]pyrene (B[a]P), a ubiquitous environmental pollutant, is a potent procarcinogen and mutagen that can elicit tumors, leading to malignancy. Heat shock proteins (Hsp) have been shown to protect cells against damages caused by various stresses including exposure to numerous chemicals. Whether Hsps, or more specifically Hsp70, are involved in repair of B[a]P-induced DNA damage is currently unknown. Methods We assessed the potential role of the inducible form of Hsp70 in B[a]P-induced DNA damage of human embryonic lung (HEL) cells using immunoblot and the comet assay (i.e., the single cell gel electrophoresis assay). Results Exposure to B[a]P induced a dose-dependent decrease in the level of Hsp70, but a dose-dependent +-increase in DNA damage both in untreated (control) HEL cells and in cells preconditioned by a heat treatment. Heat preconditioning prior to B[a]P exposure potentiated the effect of B[a]P at a low dose (10 μmol/L), but appeared to be protective at higher doses. There was a negative correlation between Hsp70 level and DNA damage in the non-preheated as well as in the preconditioned cells. Conclusion These data suggest that exposure of HEL cells to B[a]P may induce a dose-dependent reduction in the levels of the inducible Hsp70. The detailed mechanisms for the reduction of Hsp70 levels by B[a]P and the role of Hsp70 in DNA damage under different concentrations of B[a]P remains to be determined.
基金TheN ationalNaturalScienceFoundationofChina (No.40476049)andtheStateKeyLaboratoryofM arineEnvironm entalScience(X iam enU niversity),China(No.M EL201)
文摘Tributyltin(TBT), an organometal used as an antifouling biocide, has been reported to induce masculinization of fish. Benzo [a]pyrene (BaP), a widespread carcinogenic polycyclic aromatic hydrocarbon, has been reported that its microsomal metabolites can produce an estrogenic response when tested in vitro. This study was therefore designed to examine the potential in vivo influence of TBT, BaP and their mixture on sex hormone levels in serum of Sebastiscus marmoratus, which were given 2 separate intraperitoneally (ip) injections(a single injection every 7 d) of TBT(0.5, 1, 5 and 10 mg/kg), BaP(0.5, 1, 5 and 10 mg/kg), or both in combination(0.5, 1, 5 and 10 mg/kg); control fish received olive oil vehicle only. Six days after the 2nd injection, serum samples were collected and analyzed for sex hormone levels and alkali labile protein phosphorus (ALPP), which is related to the yolk precursor protein vitellogenin. The pollutants at all doses significantly reduced serum testosterone, estradiol and ALPP content after 2 injections compared with the corresponding controls. The reduction of the estradiol levels should be response for the decrease of the vitellogenin levels. The results in the present study suggested that aromatase seems not the major target acted by TBT and BaP in fish. This study demonstrated that TBT or BaP exposure both inhibit the reproductive potential in female Sebastiscus marmoratus. Combined effect of TBT and BaP on the serum testosterone, estradiol and ALPP was not antagonism from the anticipation.
基金Supported by the National Natural Science Foundation of China (No. 20962007)the Creative Talents Plan of Hainan University 211 Project
文摘Two compounds,3-oxo-N-o-tolylbenzo[d]isothiazole-2(3H)-carboxamide (1) and N-(2-methoxyphenyl)-3-oxobenzo[d]isothiazole-2(3H)-carboxamide (2),were synthesized from the initial compound benzo[d]isothiazol-3(2H)-one (BIT) and characterized by 1 H NMR,IR and elemental analysis,respectively.The single crystals of compounds 1 and 2 were obtained and determined by X-ray diffraction analysis.The preliminary results of biological activity experiment show that some of the title compounds exhibited a favorable antimicrobial activity.
基金This work was supported by the Natural Science Foundation of Hubei Province (2006ABB016)National Natural Science Foundation of China (20672041) Key Project of Science and Technology of Ministry of Education of China (107082, 106116)
文摘The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4(3H)-one (C16H18N2O3, Mr = 286.32) has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167(14), b = 13.113(1), c = 8.378(1) A, β = 98.992(2)^o, V = 1488.4(3) A^3, Z = 4, Dc = 1.278, F(000) = 608, μ = 0.089 mm^-1, MoKa radiation (2 = 0.71073), R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar.
基金This project was supported by the National Natural Science Fundation of China under contract No. 49876029.
文摘The effects on hepatic EROD (7-ethoxyresorufin O-deethylase) in Mugil so-iuy exposedto benzo(a)pyrene (BaP), pyrene and their mixtures of equal concentration were investigated, at concentrations of 0.1, 1.0, 5.0, 10.0, 50.0μg/dm3, in experimental condition. Time-effects and dose-response of the biochemical indexs were observed. The results showed that the hepatic EROD activities were induced by the exposure of BaP, pyrene and their mixtures at high concentration. Dose-response connections were that the hepatic EROD activities were elevated with increasing concentration of the pollutants. The combined effect of BaP and pyrene at 1:1 concentration ratio on hepatic EROD activity was antagonism.
基金The authors gratefully acknowledge the State Key Laboratory of Petroleum Resources and Prospecting,College of Geoscience,China University of Petroleum,Beijing,China for granting A.B.Ogbesejana an international visiting research fellowship towards this research work.
文摘The distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naptho-furans in source rocks from Niger Delta basin,Nigeria,were investigated by Rock-Eval pyrolysis and gas chro-matography--mass spectrometry(GC--MS).The data obtained from the source rocks evaluation showed that the rock samples contained type 1/III kerogen capable of generating oil and gas and were within immature to early mature stage.The relative abundance of the Cor,C1-and C2-dibenzofurans range from 1.75%to 29.82%,27.60%to 40.52%and 29.66%to 6889%,respectively.The diben-zofurans were dominated by C-dibenzofurans.Among the C1-dibenzofurans,2-+3-methyldibenzofuran was the most abundant in the rock samples while 1-methy ldibenzofuran appeared to be the least.The relative abundance of benzo[b]naphtho[1,2-d]furan(1,2]BNF),benzo[b]naph-tha[2,1-d]furan(2.1]BNF)and benzo[b]naphtha[2,3-d]fu-ran([2.3]BNF)in the rock extracts range from 12.01%to 52.58%,32.61%to 75.219%and 10.27%to 52.43%.The wide range of values recorded for the three isomers of benzo[b lnapthofurans in the samples suggest source rocks formed from mixed organic matter.Among the pheny ldibenzofuran isomers,4-pheny ldibenzofuran was the most abundant while 1-phenyldibenzofuran was the least.Phenyldibenzofuran ratio-1(PhFR-1)and pheny ldibenzofuran ratio-2(PhFR-2)values range from 0.13 to 1.20 and 0.11 to 2.11,respectively.The resuls showed that the relative abundance of PhFR-1 and PhFR-2 increase gradually with increasing burial depth and maturity(VRo≤0.77%,MPI-1≤0.62.Tmax s 443℃),and have a good correlations with calculated vitrinite reflectance.MPI-I and maximum Temperature(Tmax)-This range of values suggested immature to early mature source rocks.The source rocks were found to have shale and coul lithologics and deposited in a lacustrine/fuvial deltaic settings within immature to early mature stages based on the distribution of dibenzofurans,pheny ldiben-zofurans and benzo[b]naphthofurans in the source rocks.This study showed that dibenzof urans,phenyldibenzofu-rans and benzo[b]naphthofurans were ffcive in deter-mining the origin,depositional environment and thermal maturity of source rocks in Niger Delta basin,Nigeria.
基金Grants of National Natural Science Foundation of China (30371206, 30028019)973 National Key Basic Research and Development Program (2002 CB 512905)
文摘Objective To investigate the roles of the cyclin D1/CDK4 and E2F-1/4 pathways and compare their work patterns in cell cycle changes induced by different doses of B[a]E Methods Human embryo lung fibroblasts (HELFs) were treated with 2 μmol/L or 100 μmol/L B[a]P which were provided with some characteristics of transformed cells (T-HELFs). Cyclin D l, CDK4 and E2F-1/4 expressions were determined by Western blotting. Flow cytometry was used to detect the distribution of cell cycle. Results After B[a]P treatment, the proportion of the first gap (G 1) phase cells decreased. CDK4 and E2F-4 expression did not change significantly. In 2 μmol/L treated cells, a marked overexpression of cyclin D1 and E2F-1 was observed. However, in T-HELFs overexpression was limited to cyclin D1 only, and no overexpression of E2F-1 was observed. The decreases of G1 phase in response to B[a]P treatment were blocked in antisense cyclin D1 and antisense CDK4 transfected HELFs (A-D1 and A-K4) and T-HELFs (T-A-D1 and T-A-K4). After 2 μmol/L B[a]P treatment, overexpression of E2F-1 was attenuated in A-D1, and E2F-4 expression was decreased significantly in A-K4. In T-A-D1 and T-A-K4, E2F-4 expression was increased significantly, compared with T-HELFs. The E2F-1 expression remained unchanged in T-A-D1 and T-A-K4. Condusions Cyclin DI/CDK4-E2F-1/4 pathways work in different patterns in response to low dose and high dose B[a]P treatment. In HELFs treated with 2 μmol/L B[a]P, cyclin D1 positively regulates the E2F-1 expression while CDK4 negatively regulates the E2F-4 expression; however, in HELFs treated with 100 μmol/L B[a]P, both cyclin D1 and CDK4 negatively regulate the E2F-4 expression.
基金support by the National Science Foundation of China (NO.30671744)
文摘Objective The present study aimed to test whether exposure to benzo(a)pyrene [B(a)P] affects spatial learning and short-term memory by modulating the expression of the Gria1 and Grin2a glutamate receptor subunit genes in the hippocampus.Methods Thirty-six 21-24-day-old,male rats were randomly assigned into high-,medium-,and low-dose toxin exposure groups (6.25,2.5,and 1 mg/kg,respectively) and a control group,each containing nine rats.The behavioral performance of adult rats exposed to sub-chronic administration of B(a)P was monitored by learning and memory tests (Morris water maze).Real-time PCR assays were used to quantify Gria1 and Grin2a gene expression in the hippocampus.Results At medium and high doses,B(a)P impaired spatial learning performance.The crossing-platform-location frequency and the time spent swimming in the platform area,which both relate to short-term memory,were significantly decreased in B(a)P-treated rats compared with controls.The level of Gria1 mRNA increased 2.6-5.9-fold,and the level of Grin2a mRNA increased 10-14.5-fold,with a greater fold increase associated with higher doses of B(a)P.Conclusion We demonstrated that sub-chronic administration of B(a)P inhibits spatial learning and short-term memory,and increases Gria1 and Grin2a expression in the hippocampus.This suggests a relationship of B(a)P exposure levels with Gria1 and Grin2a expression and impairment of short-term and spatial memory.
文摘In this experiment lung carcinoma was induced by crocidolite plus benzo(a)pyrene in rat. From the cancer models, we observcd that the incidcnce (16.0%) of lung carcinomas was lowel, and the survival time (376 days) of the first case of carcinoma and the mean survival time (758 days) of the rats with carcinoma were higher in the group of rats drinking 2% green tea extract for life than in the positive group (without drinking green tea extract). The mortality ratio (0.5047) was smaller in the cxperimental group than in the positive control group, and the survival curve of the experimental group significantly raised up, in comparison with the positive group.
文摘In order to investigate the mechanism of benzo[a]pyrene uptake by a filamentous fungus Fusarium solani, a biochemical characterization of its concentrated culture filtrate has been conducted. The preparation contained approximately (w/w): 50% of total carbohydrate, 6.5% of uronic acid and 6% protein, as determined by colorimetric tests. Gel filtration and anion-exchange chromatographic profiles indicated that the main product of the culture filtrate was a glycoprotein, which contained mannose, glucose and galactose in an approximate molar ratio of 1.5: 0.8: 1. The polysaccharide fraction of the culture filtrate was prepared by treatment with proteinase K, followed by gel-filtration chromatography. Its chemical structure was studied by methylation analysis, gas-liquid chromatography-mass spectrometry (GC-MS) and Nuclear Magnetic Resonance spectroscopy (NMR). The major carbohydrate was a polymer of β-(1 → 6)-linked galactofuranose units fully branched at positions O-2 by single residues of α-glucopyranose. The Fusarium concentrated culture filtrate increased 4-fold the BaP solubilization in comparison with its aqueous solubility and suggested that the carbohydrate present in this filtrate should probably be involved in this enhancement. Our findings point out the potential role of fungal glycoproteins in PAH microbial bioavaibility, an important step for PAH biodegradation.
基金Supported by Bharathiar university.coimbatore,Tamilnadu India
文摘Objective:To identify the alleralinn of the membrane polenlial and llie effect of carolenoid extracts from Chlorococcum hnmicola(C.humicola) on membrane hound ATPases and lipid peroxidation.Methods:The lolal carotenoids were extracted from C.humicola.Four groups of Swiss albino mice were treated as control,Benzo(a)pyrene[B(a)P],total carotenoids,B(a)P+ total caralenoids respectively for a period of 60 days.Membrane lipid peroxidation and ATPases(Total ATPases,Ca^(2+)-ATPases.Mg^(2+)-ATPases.Na^+K^+- ATPasei were determined in lung,liver and erythrocyte samples.Results:The activity of lolal ATPase was found to be significantly increased in the B(a)P treated liver and lung tissue.Erythrocyte membrane also showed higher ATPase activity which was significantly reverted on total carolenoid treatment.Conclusions: It can be concluded that the changes in membrane potential favour the functional deterioration of physiological system.The overall findings demonstrates that the animals post treated with carolenoid extract from C.humicola may maintains the alterations in membrane bound ATPase and lipid peroxidation in tissues against the carcinogenic chemical and hence aid in establishing the membrane potential action.Then-fore C.humicola can be further extended to exploits its possible application for various health benefits as neulraceulicals and food additives.
基金supported by the National Natural Science Foundation of China(No.30660214)the Natural Science Foundation of Inner Mongolia Autonomous Region(No.200607010907)Doctor Initializing Fund Application of Inner Mongolia Medical College(No.2005BQ001)
文摘Objective To study the benzo(a)pyrene(B[a]P)-induced mRNA expression of aromatic hydrocarbon receptor(AHR)and cytochrome P4501A1(CYP1A1)genes in rat liver.Methods Rats were injected intraperitoneally with 5,10 and 15mg/kg of B[a]P.The total RNAs were extracted from rat livers by RNA purification kit,and the mRNA expression of AHR and CYP1A1 genes was determined by reverse transcription polymerase chain reaction(RT-PCR).β-actin was used as the internal control.The mRNA expression of both AHR and CYP1A1 genes was measured at indicated time points(24,48 and 72h)after B[a]P treatment at three different concentrations(5,10 and 15mg/kg).Results The mRNA expression of AHR gene increased in a time-dependent manner at the concentration of 10mg/kg but not at 5 and 15mg/kg of B[a]P.The mRNA expression of CYP1A1 gene differed significantly at 48h and 24h in rat livers treated with 10 and 15mg/kg dosage of B[a]P.The mRNA expression of AHR and CYP1A1 genes increased with B[a]P treatment in a concentration-dependent manner.The time-dependent increase in mRNA expression was shown by AHR but not by CYP1A1 gene with B[a]P(10mg/kg)treatment.Conclusion This study demonstrates that toxic B[a]P increases the mRNA expression of both AHR and CYP1A1 genes in vivo,suggesting that B[a]P may play a role in cancer genesis by this way.
文摘The concentrations of reduced-glutathione ( GSH) in liver and ovary of Boleophthalmus pectinirostris are quantified. The concentrations of GSH in the ovary are much higher than that of GSH in the liver(nearly 3 times of the liver). The study also investigates the changes of GSH contents in the two organs while the fishes were exposed to benzo(a)pyrene(BaP) at concentrations of 0, 0.05, 0.2 and 0.5 mg/L respectively for up to a week. The concentrations of GSH in the liver of BaP-exposed fish increased significantly with dose, whereas the concentrations of GSH in the ovary decreased significantly compared to controls. The results suggested that both the liver and the ovary are the primary organ in BaP metabolism, and that the changes of GSH levels may represent an adaptive response or toxic effect to Bap exposure.
基金financially supported by the Fundamental Research Funds for the Central Universities (No. 201762017)
文摘In this study, the RNA sequencing was used to describe the response of Nannochloropsis oceanica, a marine microalga, to benzo[a]pyrene(BaP), a polycyclic aromatic hydrocarbon, in order to elucidate the metabolic pathways(or processes) involved in microalgal response to this stubborn pollutant. N. oceanica was exposed to BaP at a concentration of 90 μg L^-1 for 72 h, and its transcriptome was sequenced through the Illumina HiSeq^TM 2500 platform. This concentration of BaP was selected as it is the lowest for modeling the most appropriate growth inhibition of N. oceanica for transcriptomic analysis. We found that N. oceanica responds to BaP through degrading proteins and repairing DNA damaged by BaP. In addition, superoxide dismutase(SOD) strengthened its performance by increasing its transcript abundance. The physiological mechanism underlining the response of N. oceanica to BaP as revealed by transcriptomic analysis was consistent with the biochemical insights documented previously.