Hydrogen Sul Fide Antagonizes Formaldrhyde-include Ferroptosis In Hippocampus Of Rats

[Background and Objective]Formaldehyde（FA）is a kind of toxic gas.It’s been demonstrated that when the metabolism of formaldehyde is unbalanced in vivo,it usually will cause brain oxidative damage,resulting in neurotoxicity.Hydrogen sulfide（H₂S）,is a kind of endogenous gas molecule,has antioxidant and neuroprotective effects.Ferroptosis is an oxidative cell death,which is closely related to many neurodegenerative diseases.This study aimed to explore whether hydrogen sulfide antagonizes formaldehyde-induced f erroptosis in rat hippocampus and provide a new idea for the prevention and treatment of formaldehyde-induced neurotoxicity.[Methods]1.Expression of glutathione-dependent antioxidant enzyme glutathione peroxidase4（GPX4）in hippocampus tissue was monitored by western blotting.2.The contents of glutathione（GSH）and malondialdehyde（MDA）,4-hydroxynonenal（4-HNE）in hippocampus tissue were detected by e nzyme-linked immunosorbent assay（ELISA）.3.The level of lipid reactive oxygen species（ROS）in hippocampus tissue was evaluated by flow cytometry after C11-BODIPY staining.4.The content of Fe²⁺in hippocampus tissue was evaluated by flow cytometry after calcein-acetoxymethlester Ca-AM staining.5.The average cross section of mitochondrial in the CA3 regions of hippocampus were observed under transmission electron microscopy.[Results]1.Formaldehyde induce ferroptosis in rat hippocampusAfter the rats were treated with 2.5μL of FA（0.1,1,10μM）by unilateral lateral ventricle micro-injection for 7d,Then the hippocampus tissue was taken for detection.1.1 The contents of GSH,MDA and 4-HNE in hippocampus of rats were detected by elisa.The results showed that treatment with FA（0.1,1,10μM）decreased the levels of GSH and increased the contents of MDA and4-HNE in a concentration-dependent manner in hippocampus.1.2 The level of GPX4 in hippocampus was detected by western blotting.The results showed that treatment with FA（0.1,1,10μM）decreased the expression of GPX4 in a concentration-dependent manner in hippocampus.1.3 The contents of ROS and Fe²⁺were detected by C11-BODIPY and Ca-AM staining,The results showed that treatment with FA（10μM）significantly increased the contents of ROS and Fe²⁺in hippocampus.1.4 Transmission electron microscopy showed that FA（1,10μM）significantly decreased the average cross section of mitochondrial in the CA3 regions of hippocampus2.Hydrogen sulfide antagonizes formaldehyde-induced ferroptosis in hippocampus of ratsAfter pretreatment with NaHS（10,30,100μmol/kg/d,i.p.）for 7h,the rats were treated with 2.5μL of FA（1μM,i.c.v.）for 7 d.2.1 The ELISA results showed that NaHS（10,30,100μmol/kg）prevented the reduction of GSH and the increase of MDA and 4-HNE in hippocampus induced by FA at concentration of 1μM.2.2 Western blotting results showed that pretreatment with NaHS（10,30,100μmol/kg）rescued the reduction of GPX4 induced by FA at concentration of 1μM.2.3 The FCM results showed that pretreatment with NaHS（10,30,100μmol/kg）antagonized the increase of ROS and Fe²⁺in hippocampus induced by FA at concentration of 1μM.2.4 Transmission electron microscopy showed that pretreatment with NaHS（30,100μmol/kg）reversed FA-induced decrease average cross section of mitochondrial in the CA3 regions of hippocampus.[Conclusion]1.Hydrogen sulfide prevents formaldehyde-induced ferroptosis in hippocampus of rats...