Proteomic analysis of chronic restraint stress-induced Gan (肝)-stagnancy syndrome in rats

To analyze the proteomic characteristics of Gan (肝)-stagnancy syndrome (GSS) by seeking the differential protein in blood and tissues of GSS model rats.

GSS model rats were established by chronic restraint stress, keeping rats in restrain chamber for 6 h every day for 21 successive days. Their blood and liver samples were collected at the end of experiment for differential protein detection with methods of isoelectrofocusing and polyacrylamide SDS-PAGE, silver staining, and scanning. The gel images were analyzed with Imagemaster 2D Elite software, and the excavated differential protein spots were identified with matrix assistant laser resolving TOF mass spectrometry, Western blot, ELISA, and RT-PCR, respectively.

A method for isolating the protein in blood serum and tissues by two-dimensional gel electrophoresis was established and optimized. Six serum proteins and three liver proteins that differentially expressed were identified. The down-regulated differential proteins in serum of GSS model rats were serum albumin precursor, beta 1 globin, antibody against muscle acetylcholine receptor, Ig lambda-2 C region, and transthyretin (TTR), and those in liver tissue were aryl sulfotransferase, enoyl-CoA hydratase, and TTR. TTR down-regulation was found in both serum and liver. Preliminary biological information analysis showed that these differential proteins involved in immune, neuroendocrine, nutrition, and substance metabolism.

Proteomic analysis of differential proteins showed that TTR, aryl sulfotransferase, and enoyl-CoA hydratase expressions are downregulated in the GSS model rats, suggesting that the susceptibility of cancer could be enhanced by chronic stress.