[Effect of ulinastatin preconditioning on gene expression profile of kidney tissue in a rat sepsis model]

To investigate the modulation effect of ulinastatin (UTI) preconditioning on gene expression of kidney tissue in septic rats by DNA microarrays.

Forty-five male Wistar rats were divided into control group, sepsis group and UTI group, with 15 rats in each group by means of random number table. Cecal ligation and puncture (CLP) was used to reproduce rat sepsis model. The control group only experienced a simulated operation without CLP. In UTI group the rats were treated with intramuscular injection of UTI (100 kU/kg). In sepsis group and control group intramuscular balanced solution (5 ml/kg) was given. Gene expression spectrum was studied with oligonucleotide gene expression profile microarray that contained 22 523 rat cDNA clones to detect the changes in gene expression pattern of rat kidney tissue 24 hours after CLP. Genes with fluorescent signal of Cy3/Cy5 of ratio average (RA)>2.0 or RA<0.5 were identified as differential genes, then those highly correlated to sepsis and UTI were screened by means of related computer software, and their relationship was analyzed.

Three hundred and twenty-seven differential genes were found in sepsis group/control group, accounting for 1.45%, and among them 181 genes showed up-regulation,with 78 known functional genes, and 146 genes showed down-regulation, with 51 known functional genes. One hundred and twenty-seven differential genes were found in UTI group/sepsis group, accounting for 0.56%, and among them 41 genes showed up-regulation, with 14 known functional genes, and 86 genes showed down-regulation, with 37 known functional genes. Twenty-two genes were down-regulated in sepsis group/control group but up-regulated in UTI group/sepsis group, with 11 known functional genes, 51 genes were up-regulated in sepsis group/control group but down-regulated in UTI group/sepsis group, with 24 known functional genes.

UTI preconditioning can alleviate the damage of kidney tissue in rat sepsis model, thus showing a protective effect on kidney, and the mechanism may be attributable to effect of UTI on modulation of immune reaction, energy metabolism, inflammatory reaction, signal transduction, defense reaction, oxidation-reduction reaction, DNA replication, and transcription related genes.