Aims:
Sulforaphane (SFN) as a nuclear factor erythroid 2-related factor 2 (Nrf2) activator protects the heart from, and deletion of the Nrf2 gene exaggerates, the effects of diabetes. Angiotensin II (Ang II) plays a critical role in the development of diabetic cardiomyopathy; therefore, whether SFN prevents Ang II-induced cardiomyopathy through activation of Nrf2 was examined.
Methods and Results:
The chronic cardiac effects of Ang II with and without SFN were examined in wild-type mice, transgenic Nrf2 knockout (Nrf2-KO) mice, and mice in which cardiac tissue overexpressed Nrf2 (Nrf2-TG). The signaling pathways of SFN-mediated Nrf2 activation were examined in H9C2 cells. Administration of a subpressor dose of Ang II to WT mice induced cardiac oxidative stress, inflammation, remodeling and dysfunction, all of which could be prevented by SFN treatment, which also up-regulated Nrf2 expression and activation. Nrf2-TG mice showed resistance and Nrf2-KO mice displayed resistance to Ang II-induced cardiomyopathy. Meanwhile, the ability of SFN to protect against Ang II-induced cardiac damage was lost in Nrf2-KO mice. Up-regulation and activation of Nrf2 by SFN is accompanied by activation of AKT, inhibition of glycogen synthase kinase (GSK)-3β, and increased nuclear accumulation of Fyn. In vitro up-regulation of Nrf2 by SFN in H9C2 cells was abolished and nuclear Fyn accumulation was increased when cells were exposed to a PI3K inhibitor or GSK-3β-specific activator.
Conclusion:
Nrf2 plays a central role in the prevention of Ang II-induced pathological effects, and SFN can prevent Ang II-induced cardiomyopathy through activation of Nrf2 partially via the AKT/GSK-3β/Fyn pathway.
Inhibition of GSK-3β restores delayed gastric emptying in obesity-induced diabetic female mice
