Protection of the liver against CCl_4-induced injury by intramuscular electrotransfer of a kallistatin-encoding plasmid

AIM:To investigate the effect of transgenic expression of kallistatin(Kal) on carbon tetrachloride(CCl 4)induced liver injury by intramuscular(im) electrotransfer of a Kal-encoding plasmid formulated with poly-Lglutamate(PLG).METHODS:The pKal plasmid encoding Kal gene was formulated with PLG and electrotransferred into mice skeletal muscle before the administration of CCl 4.The expression level of Kal was measured.The serum biomarker levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST),malonyldialdehyde(MDA),and tumor necrosis factor(TNF)-α were monitored.The extent of CCl 4-induced liver injury was analyzed histopathologically.RESULTS:The transgene of Kal was sufficiently expressed after an im injection of plasmid formulated with PLG followed by electroporation.In the Kal gene-transferred mice,protection against CCl 4-induced liver injury was reflected by significantly decreased serum ALT,AST,MDA and TNF-α levels compared to those in control mice(P < 0.01 to 0.05 in a dose-dependent manner).Histological observations also revealed that hepatocyte necrosis,hemorrhage,vacuolar change and hydropic degeneration were apparent in mice after CCl 4 administration.In contrast,the damage was markedly attenuated in the Kal gene-transferred mice.The expression of hepatic fibrogenesis marker transforming growth factor-β1 was also reduced in the pKal transferred mice.CONCLUSION:Intramuscular electrotransfer of plasmid pKal which was formulated with PLG significantly alleviated the CCl 4-induced oxidative stress and inflammatory response,and reduced the liver damage in a mouse model.

Preparation of CuS/BiVO4 thin film and its efficacious photoelectrochemical performance in hydrogen generation

To drive photoelectrochemical water splitting on porous BiVO4 photoanode,we herein prepared a carnationlike CuS powder by hydrothermal method and then loaded it onto BiVO4 photoelectrode.Expectedly,the CuS/BiVO4 composite not only presents a higher photocurrent response value at 1.23 V versus RHE(reversible hydrogen electrode)than pure BiVO4 electrode under visible light irradiation,but also exhibits an excellent photoelectrochemical hydrogen production activity in comparison with either the BiVO4 or the CuS.The high ameliorated performance of CuS/BiVO4 composite may be due to the strong absorption of visible light and an effective abatement in combination of carriers.These results demonstrate an effective potential approach to design and construct efficient photoelectrochemical(PEC)systems.

Expression of cytochrome P450 CYP81A6 in rice: tissue specificity, protein subcellular localization, and response to herbicide application

The cytochrome P450 gene CYP81A6 confers tolerance to bentazon and metsulfuron-methyl, two selective herbicides widely used for weed control in rice and wheat fields. Knockout mutants of CYP81A6 are highly susceptible to both herbicides. The present study aimed to characterize the CYP81A6 expression in rice. Quantitative real-time polymerase chain reaction（PCR） analyses demonstrated that foliar treatment of bentazon（500 mg/L） greatly induced expression of CYP81A6 in both wild-type（Jiazhe B） and its knockout mutant（Jiazhe m B）： a 10-fold increase at 9 h before returning to basal levels at 24 h in Jiazhe B, while in the mutant the expression level rose to 20-fold at 12 h and maintained at such high level up to 24 h post exposure. In contrast, metsulfuron-methyl（500 mg/L） treatment did not affect the expression of CYP81A6 in Jiazhe B within 80 h; thereafter the expression peaked at 120 h and returned gradually to basal levels by Day 6. We suggest that a metabolite of metsulfuron-methyl, 1H-2,3-benzothiazin-4-（3H）-one-2,2-dioxide, is likely to be responsible for inducing CYP81A6 expression, rather than the metsulfuronmethyl itself. Use of a promoter-GUS reporter construct（CYP81A6Pro：：GUS） demonstrated that CYP81A6 was constitutively expressed throughout the plant, with the highest expression in the upper surfaces of leaves. Subcellular localization studies in rice protoplasts showed that CYP81A6 was localized in the endoplasmic reticulum. These observations advance our understanding of CYP81A6 expression in rice, particularly its response to the two herbicides.