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Updated: Jun 30, 2026
A Doxorubicin-Induced Murine Model of Dilated Cardiomyopathy In Vivo
Published on: May 16, 2020
Protective action of doxycycline against diabetic cardiomyopathy in rats
N Yaras1, M Sariahmetoglu, A Bilginoglu
11Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey.
Background And Purpose:
Reactive oxygen and nitrogen species play an important role in the development of diabetic cardiomyopathy. They can activate matrix metalloproteinases (MMPs), and MMP-2 in particular is known to mediate early consequences of oxidative stress injury in the heart. Therefore, we investigated the role of MMP-2 and the effect of the MMP inhibitor doxycycline on the changes of heart function caused by diabetes.
Experimental Approach:
Using streptozotocin-induced diabetic rats, we evaluated the effect of doxycycline on both mechanical and electrical function of isolated hearts, papillary muscle and cardiomyocytes.
Key Results:
Doxycycline abolished the diabetes-induced depression in left ventricular developed pressure and the rates of changes in developed pressure in isolated hearts and normalized the prolongation of the action potential in papillary muscles. In cardiomyocytes isolated from doxycycline-treated diabetic rats, the altered kinetic parameters of Ca(2+) transients, depressed Ca(2+) loading of sarcoplasmic reticulum and basal intracellular Ca(2+) level, and the spatio-temporal properties of Ca(2+) sparks were significantly restored. Gelatin zymography and western blot data indicated that the diabetes-induced alterations in MMP-2 activity and protein level, level of tissue inhibitor of matrix metalloproteinase-4 and loss of troponin I were restored to control levels with doxycycline.
Conclusions And Implications:
Our data suggest that these beneficial effects of doxycycline on the mechanical, electrical and biochemical properties of the diabetic rat heart appear, at least in part, to be related to inhibition of MMP activity, implying a role for MMPs in the development of diabetic cardiomyopathy.
Insights
Diabetic cardiomyopathy impairs heart function by activating matrix metalloproteinases (MMPs). The MMP inhibitor doxycycline improved heart mechanics and electrical activity in diabetic rats, suggesting MMPs drive these cardiac changes.
Area of Science:
- Cardiology
- Biochemistry
- Pharmacology
Background:
- Diabetic cardiomyopathy involves reactive oxygen and nitrogen species.
- Matrix metalloproteinases (MMPs), particularly MMP-2, mediate oxidative stress injury in the diabetic heart.
Purpose of the Study:
- Investigate the role of MMP-2 in diabetic cardiomyopathy.
- Evaluate the therapeutic effect of the MMP inhibitor doxycycline on diabetic heart dysfunction.
Main Methods:
- Streptozotocin-induced diabetic rat model.
- Assessment of cardiac mechanical and electrical function in isolated hearts, papillary muscles, and cardiomyocytes.
- Analysis of MMP-2 activity, protein levels, and related cardiac biomarkers.
Main Results:
- Doxycycline treatment normalized left ventricular pressure and action potential duration in diabetic rats.
- Improved Ca(2+) handling and restored Ca(2+) spark properties in cardiomyocytes.
- Restored MMP-2 activity, tissue inhibitor of matrix metalloproteinase-4 levels, and troponin I to control levels.
Conclusions:
- Doxycycline ameliorates diabetic cardiomyopathy by inhibiting MMP activity.
- MMPs play a significant role in the development of diabetic heart dysfunction.
- MMP inhibition represents a potential therapeutic strategy for diabetic cardiomyopathy.
