Impact and related mechanisms of glucose fluctuations on aortic fibrosis in type 1 diabetic rats.
10.3760/cma.j.cn112148-20190628-00365
- VernacularTitle:血糖波动加剧1型糖尿病大鼠主动脉纤维化的作用机制
- Author:
Zhen Ye ZHANG
1
;
Ning WANG
1
;
Ling Ling QIAN
1
;
Shi Peng DANG
1
;
Ying WU
1
;
Xu TANG
1
;
Xiao Yu LIU
1
;
Ru Xing WANG
1
Author Information
1. Department of Cardiology, Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi 214023, China.
- Publication Type:Journal Article
- Keywords:
Aortic fibrosis;
Blood glucose;
Collagen type Ⅰ;
Diabetes mellitus, type 1;
NF-kappa B
- MeSH:
Animals;
Aorta;
Diabetes Mellitus, Experimental;
Diabetes Mellitus, Type 1;
Fibrosis;
Glucose;
Male;
NF-kappa B;
Rats;
Rats, Sprague-Dawley
- From:
Chinese Journal of Cardiology
2020;48(5):401-407
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the impact and related mechanisms of glucose fluctuations on aortic fibrosis in rats with type 1 diabetes mellitus. Methods: After injection of streptozotocin (STZ), male Sprague Dawley (SD) (8-12 weeks) rats (n=24) were randomly divided into three groups in accordance with the random number table: controlled STZ-induced diabetes (C-STZ) group (n=8); uncontrolled STZ-induced diabetes (U-STZ) group (n=8); STZ-induced diabetes with glucose fluctuations (STZ-GF) group (n=8). After three weeks, rats were sacrificed and aorta was obtained, aortic fibrosis was detected by Masson trichrome staining. The expression of collagen type 1 (collagen Ⅰ) was tested by immunofluorescence. The expression of runt-related transcription factor 2 (Runx2) was tested by immunohistochemistry. The mRNA levels of collagen Ⅰ and Runx2 were detected by quantitative real-time PCR (qRT-PCR). The protein expressions of collagen Ⅰ, Runx2 and nuclear factor (NF)-κB were determined by Western blot. Primary rat aortic smooth muscle cells (VSMCs) were cultured in three conditions: normal glucose (NG), high glucose (HG) and glucose fluctuations (GF). Cells in GF group were incubated for 72 hours with glucose alternating between 5.5 and 25 mmol/L every 12 hours. TPCA-1, the inhibitor of NF-κB, the expression of collagenⅠin different groups of cells was tested by immunofluorescence. The protein expressions of collagen Ⅰ, Runx2 and NF-κB were also determined by Western blot. Results: (1) The quantitative ratios of the area of fibrosis in the C-STZ group, U-STZ group, STZ-GF group were (8.42±0.10)%, (21.30±0.74)% and (44.39±1.09)% (P<0.05), respectively. The means of integral optical density (IOD) of collagenⅠ in the three groups were 11.92±0.88, 50.04±3.56 and 77.52±2.69, respectively (P<0.05). The mRNA levels of collagenⅠ in the three groups were 1.00±0.10, 2.02±0.28 and 2.83±0.33, respectively (P<0.05). The protein expressions of collagenⅠ in the three groups were 1.05±0.03, 2.06±0.32 and 4.93±0.25, respectively (P<0.05). (2) The average IOD of Runx2 in the three groups were 150.00±7.35, 204.84±2.32 and 391.48±7.13, respectively (P<0.05). The mRNA levels of Runx2 in the three groups were 1.02±0.02, 1.27±0.04 and 2.18±0.12, respectively (P<0.05). The protein expressions of Runx2 in the three groups were 1.03±0.01, 2.34±0.36 and 4.52±0.75, respectively (P<0.05). (3) The protein expressions of NF-κB in the three groups were 1.02±0.01, 1.96±0.13 and 2.64±0.21, respectively (P<0.05). (4) In vitro, application of inhibitor of NF-κB reversed glucose fluctuations-induced upregulation of protein levels of Col Ⅰ and Runx2 (P<0.05). Conclusion: Glucose fluctuations could aggravate aortic fibrosis through activating Runx2 via NF-κB signaling pathways.
