1.Establishment of in vitro evaluation model for CYP2B6 induction and its application to screen inducers among TCMs.
Cong XU ; Siyun XU ; Haihong HU ; Lushan YU ; Su ZENG
Acta Pharmaceutica Sinica 2013;48(1):119-24
This paper is to report the development of a high-throughput in vitro system to screen hPXR/CAR mediated CYP2B6 drug inducers, and the application of it into the quick determination of induction activity toward CYP2B6 by various commonly used traditional Chinese medicines (TCMs) extract. Dual reporter gene assays were performed. The hPXR/CAR expression vectors and the reporter vector pGL3-CYP2B6-Luc involved in the distal and proximal promoters of CYP2B6 were co-transfected into HepG2 cells. Relative luciferase activities in cell lysate were analyzed after 48 h treatment of blank vehicle or drugs to determine the induction activity toward CYP2B6 by various commonly used TCMs extract. The positive hPXR/hCAR activators rifampicin and CITCO were applied to make sure that the reporter gene model was successfully established. Then 5 kinds of commonly used TCM extracts and 1 herbal compound were successfully investigated, some were found to activate hPXR or hCAR and therefore have the potential to induce CYP2B6 enzyme. This is the first domestic article to report the hCAR3-mediated CYP2B6 induction model and the establishment of a reporter gene system for hPXR/CAR-mediated CYP2B6 induction can be an effective and systemic in vitro method to investigate the drug inducers of CYP2B6 and to explain the mechanism involved.
2.Cultivated techniques of Abrus cantoniensis under good agriculture practice
Lihua CEN ; Liang XU ; Xuehua ZHENG ; Lushan ZHOU
Chinese Traditional and Herbal Drugs 1994;0(11):-
Objective In order to standardize plantation and get bumper crops cultivation technique of Abrus cantoniensis Hance (a general term: "Herba Abri"). Methods To cultivate A. cantonients guiding by the instructive rules of productive quality and standard of management of Chinese medicinal materials, productive A. cantoniensis under good agriculture practice (GAP) promulgated by State Administration of Food and Drug. Results Comparing to production under non-GAP, the content of extract and flavones was higher, while the content of pesticide residue and heavy metal was lower under GAP. Conclusion Plantation of A. cantoniensis under GAP through choosing soil strictly, selecting seeds, optimizing pollution-free environment and friendly fertilizer and agriculture chemical, the harmful heavy metal and residues of pesticides amount in crude medicinal materials could be controled effectively so that the quality and output of A. cantoniensis could be improved.
3.Progress on cellulase and enzymatic hydrolysis of lignocellulosic biomass.
Xu FANG ; Yuqi QIN ; Xuezhi LI ; Lushan WANG ; Tianhong WANG ; Mingtian ZHU ; Yinbo QU
Chinese Journal of Biotechnology 2010;26(7):864-869
Biofuels and bio-based chemicals from lignocellulosic biomass are sustainable, making them alternatives to petroleum-derived fuels and chemicals to address the challenges of the shortage of crude oil supply and climate change resulted from the overconsumption of petroleum-based products, particularly in China. However, high cost in liberating sugars from lignocellulosic biomass is still the bottleneck of the commercialization of biofuels and bio-based chemicals. In this article, the major components of cellulases and their synergistic role in the hydrolysis of pre-treated biomass is reviewed, followed by how to evaluate the enzymatic hydrolysis. With the elucidation of the underlying mechanism of the conformations of the enzyme molecules and their effectiveness in attacking cellulose substrate, more efficient enzymes are expected to be developed. Using the high production strain Penicillium decumbens, the on-site production of cellulases for cellulose ethanol production is discussed.
Biofuels
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Biomass
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Biotechnology
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methods
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trends
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Biotransformation
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Cellulase
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biosynthesis
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Hydrolysis
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Industrial Microbiology
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methods
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trends
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Lignin
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chemistry
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metabolism
4.Three new shRNA expression vectors targeting the CYP3A4 coding sequence to inhibit its expression.
Siyun XU ; Yongsheng XIAO ; Li LI ; Lushan YU ; Huidi JIANG ; Aiming YU ; Su ZENG
Acta Pharmaceutica Sinica B 2014;4(5):350-357
RNA interference (RNAi) is useful for selective gene silencing. Cytochrome P450 3A4 (CYP3A4), which metabolizes approximately 50% of drugs in clinical use, plays an important role in drug metabolism. In this study, we aimed to develop a short hairpin RNA (shRNA) to modulate CYP3A4 expression. Three new shRNAs (S1, S2 and S3) were designed to target the coding sequence (CDS) of CYP3A4, cloned into a shRNA expression vector, and tested in different cells. The mixture of three shRNAs produced optimal reduction (55%) in CYP3A4 CDS-luciferase activity in both CHL and HEK293 cells. Endogenous CYP3A4 expression in HepG2 cells was decreased about 50% at both mRNA and protein level after transfection of the mixture of three shRNAs. In contrast, CYP3A5 gene expression was not altered by the shRNAs, supporting the selectivity of CYP3A4 shRNAs. In addition, HepG2 cells transfected with CYP3A4 shRNAs were less sensitive to Ginkgolic acids, whose toxic metabolites are produced by CYP3A4. These results demonstrate that vector-based shRNAs could modulate CYP3A4 expression in cells through their actions on CYP3A4 CDS, and CYP3A4 shRNAs may be utilized to define the role of CYP3A4 in drug metabolism and toxicity.
5.Compound from Magnolia officinalis Ameliorates White Matter Injury by Promoting Oligodendrocyte Maturation in Chronic Cerebral Ischemia Models.
Zhi ZHANG ; Xin SHU ; Qian CAO ; Lushan XU ; Zibu WANG ; Chenggang LI ; Shengnan XIA ; Pengfei SHAO ; Xinyu BAO ; Liang SUN ; Yuhao XU ; Yun XU
Neuroscience Bulletin 2023;39(10):1497-1511
Chronic cerebral hypoperfusion leads to white matter injury (WMI), which subsequently causes neurodegeneration and even cognitive impairment. However, due to the lack of treatment specifically for WMI, novel recognized and effective therapeutic strategies are urgently needed. In this study, we found that honokiol and magnolol, two compounds derived from Magnolia officinalis, significantly facilitated the differentiation of primary oligodendrocyte precursor cells (OPCs) into mature oligodendrocytes, with a more prominent effect of the former compound. Moreover, our results demonstrated that honokiol treatment improved myelin injury, induced mature oligodendrocyte protein expression, attenuated cognitive decline, promoted oligodendrocyte regeneration, and inhibited astrocytic activation in the bilateral carotid artery stenosis model. Mechanistically, honokiol increased the phosphorylation of serine/threonine kinase (Akt) and mammalian target of rapamycin (mTOR) by activating cannabinoid receptor 1 during OPC differentiation. Collectively, our study indicates that honokiol might serve as a potential treatment for WMI in chronic cerebral ischemia.
Magnolia
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White Matter
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Brain Ischemia/metabolism*
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Oligodendroglia/metabolism*