Inhibition of EGFR-STAT3 attenuates cardiomyopathy in streptozotocin-induced type 1 diabetes

in Journal of Endocrinology

Correspondence should be addressed to C Zheng or Y Wang: wallbb_1022@163.com or yi.wang1122@wmu.edu.cn

*(W Luo and L Huang contributed equally to this work)

Restricted access

Emerging evidence implicates elevated activity of STAT3 transcription factor in driving the development and progression of diabetic cardiomyopathy (DCM). We hypothesized that the fibrosis-promoting and hypertrophic actions of STAT3 are linked to the activation by epidermal growth factor receptor (EGFR). We tested this hypothesis by challenging cultured cardiomyocytes to high-concentration glucose and heart tissues of streptozotocin (STZ)-induced type 1 diabetic mice. Our results indicated that, in diabetic mice, the blockade of STAT3 or EGFR using selective inhibitors S3I-201 and erlotinib, respectively, abrogated the increased activating STAT3 phosphorylation and the induction of genes regulating fibrosis and hypertrophy in myocardial tissue. S3I-201 and erlotinib significantly reduced myocardial structural and functional deficits in diabetic mice. In cultured cardiomyocytes, high-concentration glucose induced EGFR-mediated STAT3 phosphorylation. We further showed that blockade of STAT3 or EGFR using selective inhibitors and siRNAs significantly reduced the increased expression of genes known to promote fibrosis and hypertrophy in cardiomyocytes. These results provide novel evidence that the EGFR-STAT3 signaling axis likely plays a crucial role in the development and progression of DCM.

Supplementary Materials

    • Table S1. Primer sequences for real-time quantitative PCR
    • Figure S1: Densitometric quantification for pSTAT3/STAT3 in Figure 1C. Mean + SEM; n=7; ***P<0.001, #P<0.05, ###P<0.001, and * vs DMSO, # vs T1DM.
    • Figure S2: Densitometric quantification for Col-1/GAPDH (A), TGF-β/GAPDH (B), α-MyHC/GAPDH (C), and ANP/GAPDH (D) in Figure 2E. Mean ± SEM; n=7 per group; ***P<0.001 and * P<0.05 vs DMSO; ###P<0.001 vs T1DM.
    • Figure S3: Densitometric quantification for p-STAT3/STAT3 in Figure 3A (A), p-STAT3/Lamin B in Figure 3B (B), and p-STAT3/STAT3 in Figure 3C(C). Mean ± SEM; n = 3 independent experiments; ns=no significance, ***P<0.001, **P<0.01, and * P<0.05 vs Control group; #P<0.05 and ###P<0.001 vs HG group.
    • Figure S4: Densitometric quantification for p-EGFR/EGFR in Figure 4A (A), p-STAT3/STAT3 and p-EGFR/EGFR in Figure 4B (B), p-STAT3/STAT3 and p-EGFR/EGFR in Figure 4C (C), EGFR/GAPDH in Figure 4D (D), and p-STAT3/STAT3 and STAT3/GAPDH in Figure 4E (E). Mean ± SEM; n = 3 independent experiments; ns=no significance, ***P<0.001, **P<0.01, and * P<0.05 vs Control group; #P<0.05, ##P<0.01 and ###P<0.001 vs HG group.
    • Figure S5: Densitometric quantification for Col-1/GAPDH, TGF-β/GAPDH, α-MyHC/GAPDH, and ANP/GAPDH in Figure 5B. Mean ± SEM; n = 3 independent experiments; ns=no significance, ***P<0.001, **P<0.01, and * P<0.05 vs Control group; #P<0.05, ##P<0.01 and ###P<0.001 vs HG group.
    • Figure S6: Inhibition of STAT3 or EGFR reversed HG-induced apoptosis in cardiomyocytes. (A) H9C2 cells were pretreated with S3I-201 or Erlotinib at 10 µM for 1 h, and stimulated with HG (33 mM) for 24 h. Protein levels of Bcl-2 and Bax in cells were determined by western blot assay. DMSO was used as vehicle control; GAPDH was as loading control [n=3]. B. Densitometric quantification for Bcl-2/Bax in panel A. Mean ± SEM; n = 3 independent experiments; * P<0.05 vs Control DMSO group; #P<0.05 vs HG group.
    • Figure S7: Densitometric quantification for STAT3/GAPDH in Figure 5E (A), and Col-1/GAPDH, TGF-β/GAPDH, α-MyHC/GAPDH, and ANP/GAPDH in Figure 5F (B). Mean ± SEM; n = 3 independent experiments; ***P<0.001, **P<0.01, and * P<0.05 vs Control group; #P<0.05, ##P<0.01 and ###P<0.001 vs HG group.

 

      Society for Endocrinology

Sept 2018 onwards Past Year Past 30 Days
Abstract Views 1237 1057 106
Full Text Views 106 76 6
PDF Downloads 51 41 2