Advanced Glycation End Products Increase MDM2 Expression via Transcription Factor KLF5

Figure 4

Transcription factor KLF5 regulates MDM2 gene expression. (a) Cells were treated with siRNA target of SP1 or KLF5 to test their effects on the levels of proteins. KLF5 siRNA rather than SP1 siRNA inhibited the AGE-caused changes in the protein levels. (b) SP1 siRNA knocked down the SP1 protein level; (c) KLF5 siRNA knocked down the KLF5 protein level; (d) AGEs triggered the nuclear translocation of KLF5; (e) the level of AGEs in serum of diabetic mice was increased. Serum fluorescent intensity represented the AGE level. (f) The protein levels of both KLF5 and MDM2 were increased in the colon of diabetic mice; (g–i) The bands of MDM2 (g), SP1 (h), and KLF5 (i) in Figure 4(a) were quantified using ImageJ. (j–k) The bands of SP1 (j) and KLF5 (k) in Figures 4(b) and 4(c) were quantified using ImageJ. (l–m) The bands of KLF5 in the cytosol (l) and nucleus (m) in Figure 4(d) were quantified using ImageJ. (n–o) The bands of MDM2 (n) and KLF5 (o) in Figure 4(f) were quantified using ImageJ. Every experiment was repeated at least three times. Asterisks denote significant difference compared to the control group; well number denotes significant difference compared to the healthy group within the same section of colons. and .

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