BackgroundIt is known that some environmental chemicals affect the human endocrine system. The harmful effects of endocrine disrupting chemical (EDC) nonylphenol (NP) have been studied since the 1980s. It is known that NP adversely affects physiological functions by mimicking the natural hormone 17 beta-estradiol. In the present study, we analyzed the expression of miRNAs and their target genes in mouse Sertoli TM4 cells to better understand the regulatory roles of miRNAs on Sertoli cells after NP exposure.MethodsMouse TM4 Sertoli cells were treated with NP for 3 or 24 h, and global gene and miRNA expression were analyzed using Agilent mouse whole genome and mouse miRNA v13 arrays.ResultsWe identified genes that were > 2-fold differentially expressed in NP-treated cells and control cells (P < 0.05) and analyzed their functions through Gene Ontology analysis. We also identified miRNAs that were differentially expressed in NP-treated and control cells. Of the 186 miRNAs the expression of which differed between NP-treated and control cells, 59 and 147 miRNAs exhibited 1.3-fold increased or decreased expression at 3 and 24 h, respectively. Network analysis of deregulated miRNAs suggested that Ppara may regulate the expression of certain miRNAs, including miR-378, miR-125a-3p miR-20a, miR-203, and miR-101a, after exposure to NP. Additionally, comprehensive analysis of predicted target genes for miRNAs showed that the expression of genes with roles in cell proliferation, the cell cycle, and cell death were regulated by miRNA in NP-treated TM4 cells. Levels of expression of the miRNAs miR-135a* and miR-199a-5p were validated by qRT-PCR. Finally, miR-135a* target gene analysis suggests that the generation of reactive oxygen species (ROS) following exposure to NP exposure may be mediated by miR-135a* through regulation of the Wnt/beta-catenin signaling pathway.ConclusionsCollectively, these data help to determine NP's actions on mouse TM4 Sertoli cells and increase our understanding of the molecular mechanisms underlying the adverse effects of xenoestrogens on the reproductive system.

ABSTRACT. The recent DNA microarray technology enables us to understand a large number of gene expression profiling. The technology has potential possibility to comprehend mechanism of multiple genes were related to compounds which have toxicity in biological system. So, the toxicogenomics through this technology may be very powerful for understanding the effect of unknown toxic mechanisms in biological system. We have studied that the effect of compounds related to hepatotoxin in vivo system using DNA microarray and classified chemicals which have been well characterized. We have studied three compounds; 2 peroxisome proliferators: Clofibrate (ethyl-p-chlorophenoxyisobutyrate), gemfibrozil (5-2[2,5-dimethyl-phenoxy]2-2-dimethyl-pentanonic), and an antiepileptic drug: phenytoin (5,5-diphenylhydantoin). Male Sprague-Dawely VAF + albino rats of 5-6 weeks old were treated with each compound for 24 hr and 2 weeks. 4.8 K cDNA microarray in house has been used for gene expression profiling. We found that the clustering of gene expression had similarity like as the toxic phenotype of compounds. KEY WORDS: gene expression, microarray, peroxisome proliferators, phenytoin, toxicogenomics.J. Vet. Med. Sci. 66(11): 1329-1333, 2004 We are gaining information of numerous candidate genes that have been known and unknown their function in biological system through many projects has been done and are processing. Many techniques that are able to analyze many genes and proteins simultaneously in once are used to interpret the information. Microarray technology, one of them, permits the comparison of thousands of genes in different biological systems. Lately, microarray system has been used for the prediction of toxicity through gene expression induced toxicant [15,18] and has shown that compounds with similar toxic mechanisms produce similar changes in gene expression in vivo [5] and in vitro system [2]. As these results, many pharmaceutical companies and research groups are making databases of gene expression related to toxic mechanism induced by compounds that were well characterized. These collected databases of microarray associated with toxicity will shorten the toxicity evaluation steps that are often the rate-limiting step in the discovery and development of new pharmaceuticals.In this study, we have used cDNA microarray methods for analysis of the effect of 3 compounds related to hepatotoxin including 2 peroxisome proliferators: clofibrate (ethyl-p-chlorophenoxyisobutyrate), gemfibrozil (5-2[2, 5-dimethyl-phenoxy] 2-2-dimethyl-pentanonic), and an antiepileptic drug: phenytoin (5, 5-diphenylhydantoin). The peroxisome proliferators have been studied in many toxic study groups because most of peroxisome proliferators have hepatic toxicity. It has been shown that peroxisome proliferator activated receptors play a significant role in regulation of lipid metabolism, hepatic peroxisomal genes expression, insulin sensitivity and glucose homeostasis [8,9]. Also, it was known that phenytoin is an anticonvulsant and cardiac depressan...

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Presently, it is important to address the harmful effects of environmental chemicals on living organisms. The toxic effects of bisphenol A (BPA), one of the endocrine disruption chemicals (EDCs), have been documented in many studies since the 1930s. However, BPA has continued to be used to make polycarbonate plastic, etc. Therefore, it is necessary to conduct toxicogenomic studies to assess the harmful effects of BPA. In this study, microarray technology was used to study the harmful effects format the genomic level. We used two types of microarray chips to study of the relationship between gene and miRNA expression profiles, the Agilent mouse genome 4 44 K array for gene expression profiling and the Agilent mouse miRNA v13 for miRNA expression profiling. As a result, we identified 37 miRNAs that were 2-fold up-or down-regulated within 24 hrs than 3 hrs of BPA treat times. The gene expression patterns related to miRNAs were classified into a total of 4 groups. The first and third groups and the second and fourth groups had similar functions to each other as determined by related gene expression. In the first and third groups included overexpressed genes that were related to metabolism. The second and fourth groups included overexpressed genes that were related to reproduction. miRNA expression levels were exchanged for BPA degradation. So, genes of related metabolism were overexpressed. This result was occurred the side effect that was down-expression of reproduction. Thus, miRNAs were regulated by BPA, and gene expression was subsequently regulated by miRNAs.