Yun Yun1, Chang-Zhong Wang, Li Gui, Zhen-Xing Li. 1. School of Integrated Chinese and Western Medicine, Anhui University of Traditional Chinese Medicine, Hefei 230038, China. zkdyy0101@163.com
Abstract
OBJECTIVE: To investigate the effect and mechanism of baicalin against beta-lactamases Escherichia coli (ESBLs E. coli) mediated by toll-like receptor 4 (TLR4) signal transduction pathway. METHOD: The RAW264. 7 cells monolayer pretreated with different concentration of baicalin were inoculated with ESBLs E. coli. The expression of TLR4 mRNA and protein were analyzed by semi-quantitative RT-PCR and Immunofluorescence, respectively. The activity of NF-kappaB was detected by Western blot using total cellular protein. The production of TNF-alpha in supernatant was determined by enzyme linked immunosorbnent assay (ELISA). RESULT: ESBLs E. coli significantly up-regulated the expression levels of TLR4 mRNA and protein in a time-dependent manner, induced the activation of NF-KB in RAW264. 7, enhanced the production of TNF-alpha in supernatant. Baicalin down-regulated the expression of TLR4 mRNA and protein, decreased the activation of NF-KB in RAW264. 7 cells and reduced the production of TNF-alpha in supernatant in a dose-dependent manner. CONCLUSION: Baicailin could inhibit TLR4 signal transduction pathway. The mechanism of baicalin against ESBLs E. coli may be through inhibiting the expression of TLR4 and its signal transduction pathway.
OBJECTIVE: To investigate the effect and mechanism of baicalin against beta-lactamases Escherichia coli (ESBLs E. coli) mediated by toll-like receptor 4 (TLR4) signal transduction pathway. METHOD: The RAW264. 7 cells monolayer pretreated with different concentration of baicalin were inoculated with ESBLs E. coli. The expression of TLR4 mRNA and protein were analyzed by semi-quantitative RT-PCR and Immunofluorescence, respectively. The activity of NF-kappaB was detected by Western blot using total cellular protein. The production of TNF-alpha in supernatant was determined by enzyme linked immunosorbnent assay (ELISA). RESULT: ESBLs E. coli significantly up-regulated the expression levels of TLR4 mRNA and protein in a time-dependent manner, induced the activation of NF-KB in RAW264. 7, enhanced the production of TNF-alpha in supernatant. Baicalin down-regulated the expression of TLR4 mRNA and protein, decreased the activation of NF-KB in RAW264. 7 cells and reduced the production of TNF-alpha in supernatant in a dose-dependent manner. CONCLUSION: Baicailin could inhibit TLR4 signal transduction pathway. The mechanism of baicalin against ESBLs E. coli may be through inhibiting the expression of TLR4 and its signal transduction pathway.
Authors: Zakary J Hambsch; Mitchell J Kerfeld; Daniel R Kirkpatrick; Dan M McEntire; Mark D Reisbig; Charles F Youngblood; Devendra K Agrawal Journal: Clin Transl Sci Date: 2015-08-14 Impact factor: 4.689