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bioRxiv · 10.1101/2020.12.23.424095

QKI 6 ameliorates CIRI through promoting synthesis of triglyceride in neuron and inhibiting neuronal apoptosis associated with SIRT1-PPARγ-PGC-1α axis

Abstract

The stroke induced by ischemia of brain remains high incidence and death rate. The study wanted to confirm the effects of QKI 6 on the protection role in neurons of rat model of cerebral ischemia/reperfusion injury (CIRI). The rat model with CIRI induced by MCAO (middle cerebral artery occlusion) was well established and rat neurons were isolated to characterize the effects of QKI 6 mediated by SIRT1 on synthesis of triglyceride in neuron and neuronal apoptosis via activation of SIRT1-PPAR{gamma}-PGC-1 signaling pathway. The expression levels of SIRT1 or QKI 6, and acetylation level of QKI 6 was decreased in neurons of rat model with CIRI. QKI 6 deacetylated and mediated by SIRT1 that contributed to suppressing the progression of neuronal apoptosis in rat through promoting synthesis of triglyceride in vivo and in vitro via SIRT1-PPAR{gamma}-PGC-1 signaling pathway, then inhibiting CIRI. In conclusion, our results demonstrated SIRT1 deacetylates QKI 6, the RNA-binding protein, that affects significantly the synthesis of triglyceride in neurons of CIRI rat model. Moreover, it activated transcription factor PGC-1 through post-transcriptional regulation of the expression of PPAR{gamma}, and further enhanced synthesis of triglyceride, thereby restrained the progression of neural apoptosis and CIRI.

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BibTeXRIS

Liu, R.. 2020-12-23. QKI 6 ameliorates CIRI through promoting synthesis of triglyceride in neuron and inhibiting neuronal apoptosis associated with SIRT1-PPARγ-PGC-1α axis. https://doi.org/10.1101/2020.12.23.424095

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