Establishment of a cell-based drug screening model for identifying down-regulators of Protein Tyrosine Phosphatase 1B expression.

Protein Tyrosine Phosphatase 1B (PTP1B), an important negative regulator of insulin signaling, is thought to be an attractive therapeutic target for insulin resistance and type 2 diabetes. For the aim of screening PTP1B expression down-regulators, we established the drug screening cellular model based on transcriptional regulation of PTP1B. In this study, the promoter sequences of PTP1B were cloned into pGL3B-neo vector containing luciferase gene and neomycin resistance gene. The recombinant reporter gene vector pGL3B-neo /PTP1B was transfected into CV1 cells and therefore stable cell line, namely SPTP1B, was obtained. With the cell-based reporter gene assay, we detected more than one hundred compounds in microtiter wells. In the screening process, the compound CM107 which had extracted from the traditional Chinese medicinal herbs was identified to repress the activity of PTP1B promoter significantly in mode of dose-dependence.

Establishment of a cell-based drug screening system for identifying selective down-regulators of mPGES-1.

OBJECTIVE: To establish a drug screening system based on transcriptional regulation of microsomal PGE(2) synthase 1 (mPGES-1), cyclooxygenase 1 (COX-1) and 2 (COX-2) for discovering selective down-regulators of mPGES-1. METHODS: The upstream regulatory sequences of mPGES-1, COX-1, COX-2 were respectively cloned into pGL3B-neo vector containing luciferase gene and neomycin resistance gene (the pGL3B-neo vector had been previously constructed by cloning the neomycin resistance gene into the Sal I site of the pGL3-Basic vector). After that, the recombinant reporter gene vectors pGL3B-neo/mPGES-1, pGL3B-neo/COX-1, pGL3B-neo/COX-2 were respectively transfected into A549 cells and therefore stable cell lines, namely M 1, M 2 and M 3, were obtained. Samples were detected then by testing luciferase activity of M 1, M 2 and M 3 cells in microtiter wells to identify compounds that can selectively down-regulate mPGES-1 expression. Through luciferase activity testing, the compounds which had more than 40 % inhibition ratio on M 1 and less than 20 % inhibition ratio on M 2 and M 3 cells could be regarded as hits. RESULTS: Using the cell-based reporter gene assay, we screened compounds for selectively down-regulation of mPGES-1 expression and several compounds were discovered. CONCLUSION: A cell-based drug screening system was established to screen selective down-regulators of mPGES-1 expression, and compound CM188 was identified, which might become a lead compound for novel anti-arthritic drugs.

[Seroepidemiological study of HBV and HCV infection in sexually promiscuous groups].

A serological study on the detection of HBV and HCV infection markers and the investigation of related sexual behaviors were conducted among 431 female prostitutes and 109 normal women. The result showed of anti-HBc prevalence rate was 43.1% (186/431), anti-HBs positive rate was 36.9% (159/431), HBsAg positive rate was 11.1% (48/431) and anti-HCV positive rate 9.51% (41/431). They were all significantly higher in prostitutes than in normal women. The infection indexes of HBV and HCV were also higher in population with STD than in normal women. The prevalence of anti-HCV in female prostitutes tended to increase with increase of age. There was a significant correlation with the number of their clients and years of being prostitutes. This demonstrated that there was a relatively high HBV and HCV infection rates in prostitutes.