Fisetin alleviates cerebral ischemia/reperfusion injury by regulating Sirt1/Foxc1/Ubqln1 pathway-mediated proteostasis
Related Experiment Video
Updated: Jul 1, 2025
Herbal Munziq Ameliorates Myocardial Ischemia-Reperfusion Injury by Inhibiting Inflammation
Published on: January 10, 2025
Xunhu Gu1, Yuqin Xie2, Qian Cao1
1Department of Neurology, The Second Affliated Hospital of Nanchang University, Nanchang 330006, Jiangxi, China.
Background:
Cerebral ischemia/reperfusion injury (IRI) is pathologically associated with protein damage. The flavonoid fisetin has good therapeutic effects on cerebral IRI. However, the role of fisetin in regulating protein damage during cerebral IRI development remains unclear. This study investigated the pharmacological effects of fisetin on protein damage during cerebral IRI progression and defined the underlying mechanism of action.
Methods:
In vivo and in vitro models of cerebral IRI were established by middle cerebral artery occlusion/reperfusion (MACO/R) and oxygen-glucose deprivation/reperfusion (OGD/R) treatment, respectively. Triphenyl tetrazolium chloride staining was performed to detect cerebral infarct size, and the modified neurologic severity score was used to examine neurological deficits. LDH activity and protein damage were assessed using kits. HT22 cell vitality and apoptosis were examined using CCK-8 assay and TUNEL staining, respectively. Interactions between Foxc1, Ubqln1, Sirt1, and Ezh2 were analyzed using CoIP, ChIP and/or dual-luciferase reporter gene assays.
Results:
Fisetin alleviated protein damage and ubiquitinated protein aggregation and neuronal death caused by MCAO/R and OGD/R. Ubqln1 knockdown abrogated the inhibitory effect of fisetin on OGD/R-induced protein damage, ubiquitinated protein aggregation, and neuronal death in HT22 cells. Further experiments demonstrated that Foxc1 functions as a transcriptional activator of Ubqln1 and that Sirt1 promotes Foxc1 expression by deacetylating Ezh2 and inhibiting its activity. Furthermore, Sirt1 knockdown abrogated fisetin-mediated biological effects on OGD/R-treated HT22 cells.
Conclusion:
Fisetin improved proteostasis during cerebral IRI by regulating the Sirt1/Foxc1/Ubqln1 signaling axis. Our findings strongly suggest that fisetin-mediated inhibition of protein damage after ischemic stroke is a part of the mechanism through which fisetin is neuroprotective in cerebral IRI.
Insights
The flavonoid fisetin protects against brain damage after stroke by improving protein stability. Fisetin regulates the Sirt1/Foxc1/Ubqln1 pathway, reducing protein damage and neuronal death in cerebral ischemia/reperfusion injury.
Area of Science:
- Neuroscience
- Biochemistry
- Pharmacology
Background:
- Cerebral ischemia/reperfusion injury (IRI) is linked to significant protein damage.
- The flavonoid fisetin demonstrates therapeutic potential for cerebral IRI.
- The precise role of fisetin in mitigating protein damage during cerebral IRI is not fully understood.
Purpose of the Study:
- To investigate the pharmacological effects of fisetin on protein damage in cerebral IRI.
- To elucidate the underlying molecular mechanisms by which fisetin exerts its effects.
Main Methods:
- Established in vivo (middle cerebral artery occlusion/reperfusion) and in vitro (oxygen-glucose deprivation/reperfusion) models of cerebral IRI.
- Assessed infarct size, neurological deficits, LDH activity, and protein damage.
- Utilized CCK-8 and TUNEL assays to evaluate cell viability and apoptosis.
- Employed Co-immunoprecipitation, ChIP, and dual-luciferase reporter assays to analyze molecular interactions.
Main Results:
- Fisetin treatment reduced protein damage, ubiquitinated protein aggregation, and neuronal death in both in vivo and in vitro models.
- Knockdown of Ubqln1 abolished the protective effects of fisetin against OGD/R-induced damage.
- Foxc1 was identified as a transcriptional activator of Ubqln1.
- Sirt1 promoted Foxc1 expression by deacetylating and inhibiting Ezh2 activity, with Sirt1 knockdown negating fisetin's benefits.
Conclusions:
- Fisetin enhances proteostasis in cerebral IRI by modulating the Sirt1/Foxc1/Ubqln1 signaling pathway.
- Fisetin's neuroprotective effects in cerebral IRI involve the inhibition of protein damage via this pathway.
