Analysis of differentially expressed advanced glycation end product-modified proteins in diabetic rat kidney

作者:Liu, Jingfang*; Wang, Lu; Tang, Xulei*; Fu, Songbo; Tian, Yunling; Ma, Lihua
来源:International Journal of Diabetes in Developing Countries, 2018, 38(4): 417-423.
DOI:10.1007/s13410-018-0616-3

摘要

The objective of the study is to analyze and identify differentially expressed advanced glycation end product (AGE)-modified proteins in diabetic rat kidney tissues. A total of 60 healthy male Sprague-Dawley rats were randomly divided into the normal control group, 1-month diabetic group, and 3-month diabetic group. Two percent streptozotocin (55kg/kg) was intraperitoneally injected to establish the diabetic rat model. AGE-modified protein concentrations in the renal tissues were measured by ELISA. The differentially expressed AGE-modified proteins in renal tissues were separated with one-dimensional electrophoresis (1-DE) Western blotting and analyzed and identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). AGE-modified protein concentrations in the 1-month diabetic group (420.9 +/- 53.0g/mL) and 3-month diabetic group (618.8 +/- 86.1g/mL) were significantly higher than the control group (332.3 +/- 51.4g/mL) (p<0.05 and p<0.001, respectively). AGE-modified protein concentrations in the 3-month diabetic group were higher than in the 1-month diabetic group (p<0.001). The blood glucose levels were positively correlated with AGE-modified protein concentrations in the diabetic groups (r=0.4303, p=0.4303). Four differentially expressed AGE-modified proteins were separated with 1-DE Western blotting, of which the expression levels of three proteins were twofold higher in the 3-month diabetic group as compared to the control group or 1-month diabetic group. The four upregulated proteins were identified by MALDI-TOF-MS as actin, transferrin, catalase, and albumin. Non-enzyme glycosylation of proteins may affect the structure of these proteins and probably the functions and cause kidney damage in diabetic rats.

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