Investigation On The Neuroprotective Effect Of Itaconate/Nrf2/HO-1 Signaling And Its Underlying Mechanism In Intracerebral Hemorrhage Injury

Subject: To explore whether itaconate can alleviate the secondary injury of intracerebral hemorrhage in vivo and find its possible mechanism.Method: For the purpose of exploring the new function of itaconate,we selected dimethyl itaconate(DI,cell permeability derivative of itaconate)to explore from animal model.Male SD rats were randomly divided into five groups: sham operation group(Sham),cerebral hemorrhage group(ICH),solvent group(ICH+Veh),DI treatment group(ICH+DI)and ML385 treatment group(ICH+DI+ML385).mNSS score was used to detect the neurobehaviour in the model-making rats;Measurement of Water Content of Brain Tissue by dry-wet Heavy Method.The protein expression levels of the Nrf2、HO-1、1L-1β、NF-κB were measured by western blot,and main proteins included Nrf2、HO-1 expression level around the bleeding area was detected by fluorescence staining of frozen sections of the rat brain,and the damage of neurons was detected by FJC staining.All the data and the charts were analyzed by statistical software.Result: In animal experiments,the SD rats in the DI group had a lower mNSS score than the cerebral hemorrhage group.In the detection of brain water content,the DI group was significantly lower than the ICH group.The number of denatured neurons decreased in DI group compared with ICH group in FJC fluorescence staining.DI group had lower levels of Evans blue in the brain.All these trends can be ML385 inhibited,indicating that the neurological function of the DI group was significantly improved compared with that of the ICH group and could be inhibited by Nrf2 inhibitors.The expression of inflammatory factor 1 L-1β、IL-6 in DI group decreased,indicating that DI had anti-inflammatory effect.The results of Western-blot and immunofluorescence assay showed that the expression level of Nrf2、HO-1 protein in brain tissue of DI group was higher than that in ICH group.Conclusion: The FJC staining,BBB permeability and hematoma area of cerebral water content in the DI treatment group showed a downward trend,indicating that DI could relieve the symptoms of partial neuronal degeneration,blood-brain barrier destruction,edema and hematoma after ICH;The expression of inflammatory factor 1 L-1β、IL-6 in DI treatment group showed a decreasing trend,indicating that DI had anti-inflammatory effect in ICH.mRNA、Western blot、immunofluorescence staining showed a upward trend about DI group,indicating that DI had an activation antioxidant effect on Nrf2/HO-1 signaling pathway in ICH,further identified the key role of Nrf2 in DI neuroprotective role through the inhibitor group.Taken together,DI attenuates secondary injury after ICH by regulating Nrf2/HO-1 signaling pathways.