Effects of Orexin-A/OX1R/OX2R on iron death and lipid peroxidation regulation in chronic unpredictable mild stress depressed rats
ZHANG Zhen
CHENG Ming
JIANG Zhaoshu
YANG Jie
LUO Zhenliang
CAO Feng
Abstract：Objective To investigate whether orexin A(orexin-A),orexin receptor 1(OX1R)and orexin receptor 2(OX2R)are involved in iron death and lipid peroxidation regulation in chronically unpredictable mild stress(CUMS)depressed rats.Methods Forty rats were randomly divided into a normal group(NC group),a modeling group(Mod group),an exogenous Orexin-A group(Orexin-A group,),and an OX1R/OX2R blocker group(TCS1102 group),with 10 rats in each group.After modeling,behavioral changes were observed using the absent field test(OFT),sugar-water preference test(SPT)and forced swimming test(FST),action potential(PA)and resting membrane potential(Vm)were detected by diaphragm-clamp technique,Orexin-A/OX1R/OX2R protein expression in orbital frontal cortex(OFC)tissues was detected by protein immunoblotting(WB)method,RT-PCR The mRNA expression of glutathione peroxidase 4(GPX4),long chain acyl coenzyme A synthase 4(ACSL4)and cysteine/glutamate transporter light chain(SLC7A11)were detected by RT-PCR method,and the intensity of the expression of rat glial fibrillary acidic protein(GFAP)and lipid peroxidation product 4-hydroxynon-enal(4-HNE)was labeled by immunofluorescence.Results Compared with the NC group,there were significant differences in OFT,SPT and FST behavioral in the Mod group(P<0.01),with lower number of PA issuance(P<0.001),higher Vm(P<0.01),and higher expression of Orexin-A/OX1R/OX2R proteins(P<0.01,P<0.001,and P<0.001).GPX4/SLC7A11 mRNA expression was decreased(P<0.01),ACSL4 mRNA expression was elevated(P<0.01),and the fluorescence intensity expression of both GFAP and 4-HNE was elevated(P<0.001);the number of PA issuance was decreased in the Orexin-A group compared to the Mod group(P<0.05),and the Orexin-A/OX1R/OX2R protein expression was elevated(P<0.05,P<0.01),GPX4/SLC7A11 mRNA ex-pression was decreased(P<0.05),ACSL4 mRNA expression was elevated(P<0.05),and the fluorescence in-tensity of GFAP and 4-HNE expression was elevated(P<0.05,P<0.01);the TCS1102 group had higher expres-sion of GFAP and 4-HNE in the behavioral,Orexin-A/OX1R/OX2R protein expression,PA and Vm,GPX4/SLC7A11/ACSL4 mRNA,and GFAP and 4-HNE fluorescence intensity expression showed a reversed trend.Con-clusions Orexin-A/OX1R/OX2R is involved in the regulation of iron death and lipid peroxidation in CUMS de-pressed rats,and the mechanism may be that Orexin-A enhances the excitability of OFC neurons by activating the OX1R/OX2R signaling pathway,up-regulates the expression of the key factor of iron death,ACSL4/4-HNE,and decreases the expression of GPX4/SLC7A11,which promotes lipid peroxidation and iron death.
Keywords：orexindepressioniron deathlipid peroxidationorbitofrontal cortex
Publication Date：2025-08-25
Online Publishing Date：2025-09-04(First online date of this platform, not the publication date of the document)
Pages：8( 2507-2514 )