Online_Appendix-10212021-final.pdf (1.09 MB)
Methazolamide Attenuates the Development of Diabetic Cardiomyopathy by Promoting β-Catenin Degradation in Type 1 Diabetic Mice
figure
posted on 2022-01-18, 17:51 authored by Xiaoqing Chen, Yilang Li, Xun Yuan, Wenchang Yuan, Conglin Li, Yue Zeng, Yuling Lian, Xiaoxia Qiu, Yuan Qin, Guiping Zhang, Xia-Wen Liu, Chengfeng Luo, Jiandong Luo, Ning HouMethazolamide
(MTZ), a carbonic anhydrase inhibitor, has been shown to inhibit cardiomyocyte
hypertrophy and exert a hypoglycemic effect in patients with type 2 diabetes
mellitus and diabetic db/db mice. However, whether MTZ has a cardioprotective
effect in the setting of diabetic cardiomyopathy is not clear. We investigated
the effects of MTZ in a mouse model of streptozotocin-induced type 1 diabetes mellitus
(T1DM). Diabetic mice received MTZ by
intragastric gavage (10, 25, or 50 mg/kg; daily for 16 weeks). In the diabetic
group, MTZ significantly reduced both random and fasting blood glucose levels and
improved glucose tolerance in a dose-dependent manner. MTZ ameliorated
T1DM-induced changes in cardiac morphology and dysfunction. Mechanistic analysis
revealed that MTZ blunted T1DM-induced enhanced expression of β-catenin. Similar results were observed in neonatal rat cardiomyocytes (NRCMs) and adult mouse cardiomyocytes treated
with high glucose or Wnt3a (a β-catenin activator). There was no
significant change in β-catenin mRNA levels in cardiac tissues or NRCMs. MTZ-mediated
β-catenin downregulation was recovered by MG132, a proteasome inhibitor. Immunoprecipitation
and immunofluorescence analyses showed augmentation of AXIN1–β-catenin interaction
by MTZ in T1DM hearts and in NRCMs treated with Wnt3a; thus, MTZ may potentiate
AXIN1–β-catenin linkage to increase β-catenin degradation. Overall, MTZ may alleviate
cardiac hypertrophy by mediating AXIN1–β-catenin interaction to promote degradation
and inhibition of β-catenin activity. These findings may help inform novel therapeutic
strategy to prevent heart failure in patients with diabetes mellitus.