OBJECTIVE: Isoproterenol (ISO) is widely used agent to study the effects of interventions which could prevent or attenuate the development of myocardial infarction. The sequence of pathological event's revealed that increased myocardial tissue oxygen demand and energy dysregulation exist early during Iso-induced cardiac toxicity. Later, tissue hypoxia results in increased oxidative stress, inflammation and fibrosis along with cardiac dysfunction in this model. The canonical Wnt/β-catenin pathway has been reported to directly implicate in inducing cardiomyocyte hypertrophy and remodelling. However, less is known about the role of non-canonical Wnt signalling in cardiac diseases. METHOD: Certain evidences have suggested that the activation of Wnt could up-regulate key energy sensor and cell growth regulator mTOR (Mechanistic target of rapamycin) by inhibition of GSK-3β mediator. RESULT: The GSK-3β could negatively influence the mTOR activity and produce energy dysregulation during stress or hypoxic conditions. This suggests that the inhibition of GSK-3β by Wnt signalling could up-regulate mTOR levels and thereby restore early myocardial tissue energy balance and prevent cardiac toxicity in rodents. CONCLUSION: We hereby discuss a novel therapeutic role of the β-catenin independent, Wnt-GSK3-mTOR axis in attenuation of Iso-induced cardiotoxicity in rodents.
OBJECTIVE: Isoproterenol (ISO) is widely used agent to study the effects of interventions which could prevent or attenuate the development of myocardial infarction. The sequence of pathological event's revealed that increased myocardial tissue oxygen demand and energy dysregulation exist early during Iso-induced cardiac toxicity. Later, tissue hypoxia results in increased oxidative stress, inflammation and fibrosis along with cardiac dysfunction in this model. The canonical Wnt/β-catenin pathway has been reported to directly implicate in inducing cardiomyocyte hypertrophy and remodelling. However, less is known about the role of non-canonical Wnt signalling in cardiac diseases. METHOD: Certain evidences have suggested that the activation of Wnt could up-regulate key energy sensor and cell growth regulator mTOR (Mechanistic target of rapamycin) by inhibition of GSK-3β mediator. RESULT: The GSK-3β could negatively influence the mTOR activity and produce energy dysregulation during stress or hypoxic conditions. This suggests that the inhibition of GSK-3β by Wnt signalling could up-regulate mTOR levels and thereby restore early myocardial tissue energy balance and prevent cardiac toxicity in rodents. CONCLUSION: We hereby discuss a novel therapeutic role of the β-catenin independent, Wnt-GSK3-mTOR axis in attenuation of Iso-induced cardiotoxicity in rodents.
Authors: Carolyn L Buller; Robert D Loberg; Ming-Hui Fan; Qihong Zhu; James L Park; Eileen Vesely; Ken Inoki; Kun-Liang Guan; Frank C Brosius Journal: Am J Physiol Cell Physiol Date: 2008-07-23 Impact factor: 4.249