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Irisin deficiency exacerbates diet-induced insulin resistance and cardiac dysfunction and promotes ischemia and reperfusion injury

ABSTRACT: The myokine irisin is involved in the regulation of a variety of physiological conditions, metabolism, and survival. We and others have demonstrated that recombinant irisin contributes critically to modulation of insulin resistance and cardiac function. However, the molecular mechanisms by which irisin exerts its physiological effects on cardiac function and insulin sensitivity remain unclear. We utilized the CRISPR/Cas9 genome editing system to delete irisin. Irisin deficiency did not result in abnormalities in development, growth, or cardiac function; however, gene expression profiling showed that several key signaling pathways related to growth, insulin signaling, and integrin signaling were coordinately downregulated. However, loss of irisin resulted in more severe insulin resistance and metabolic derangement when mice were exposed to a high fat diet, which was associated with profound cardiac dysfunction and hypertrophic remodeling. In addition, the loss of irisin also exacerbated myocardial ischemia-reperfusion injury, as indicated by a reduction of post-ischemic ventricular function and an increase in infarct size. Taken together, our results indicate that loss of irisin exacerbates insulin resistance and cardiac depression in response to high fat diet and promotes myocardial ischemia-reperfusion injury. This evidence suggests a role for irisin in modulating insulin resistance, cardiac function and ischemic injury.

ORGANISM(S): Mus musculus

PROVIDER: GSE231597 | GEO | 2023/11/08

REPOSITORIES: GEO

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Project description:The management of cardiac ischemic injury has been challenged by ischemia and reperfusion (I/R) injury. Reactive oxygen species (ROS) generated from mitochondrial reverse electron transport (RET) during the early phase of reperfusion is considered to be the initiating cause for ischemia and reperfusion injury. Ginsenosides and their prescriptions are widely used in the clinic for treatment of myocardial ischemia, however, the action to combat ROS remains to be elucidated. In this work, we used TMT-based proteomic approach to detect differential proteins from mitochondrial fractions of mice hearts with ischemia-reperfusion. Results indicated that the mass error of identified peptides was within 10 ppm, and most of the identified peptides were composed of 7-23 amino acids. Using these qualified data, 17,262 peptides, with a confidence level ≥ 95%, were mapped to 3,054 protein groups. PCA analysis showed that the model group was clearly separated from the blank group, while the protein pattern was partly reversed with Rb1 treatment. With a criteria of p-value < 0.05, 591 significantly changed proteins including 186 increased and 405 decreased ones in the model group were identified compared with the blank group. These proteins were divided into 4 clusters. Proteins in Cluster I highly increased in the model group, but clearly decreased in the Rb1 group. Proteins in Cluster IV clearly decreased in the model group, but markedly increased in the Rb1 group. Proteins in Cluster III and in Cluster IV were not significantly or slightly regulated by the Rb1 treatment. GO analysis of Cluster I and II indicated that the molecular function of these proteins were closely related to oxidoreductase activity and NADH dehydrogenase activity. Our result showed that Rb1 administration before ischemia markedly decreased infarct size (48 h post-I/R), and preserved cardiac function (2 weeks post-I/R), and subsequently limited tissue fibrosis (28 days post-I/R). These results indicated that targeted inhibition of mitochondrial complex I in the early stage of reperfusion by Rb1 is a potential therapeutic strategy for alleviating IR injury. This work not only indicates a potent molecular target for the precision therapy of myocardial ischemia by Rb1, but also provides novel knowledge for the management of cardiac ischemic injury by traditional Chinese medicine.

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Irisin deficiency exacerbates diet-induced insulin resistance and cardiac dysfunction and promotes ischemia and reperfusion injury

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