丰富环境通过上调海马LASP1改善父系应激致子代小鼠焦虑抑郁样行为

Environmental enrichment ameliorates anxiety and depression-like behaviors in paternally stressed offspring mice through upregulation of hippocampal LASP1

目的探索丰富环境(environmental enrichment,EE)在父系应激致子代焦虑、抑郁样行为中的作用及其可能机制。方法给予雄性C57BL/6小鼠(F0)慢性温和不可预知应激(unpredictable chronic mild stress,UCMS),随后与正常雌鼠交配获得F1子代(F1-UCMS)小鼠。在F1-UCMS子代小鼠幼年期(3~5周龄)分别给予标准环境(standard environment,SE)和丰富环境(EE)干预,成年后(8周龄)采用旷场实验(open field test,OFT)、高架十字迷宫实验(elevated plus-maze test,EPM)检测小鼠焦虑样行为,采用强迫游泳实验(forced swimming test,FST)、糖水偏好实验(sucrose preference test,SPT)检测小鼠抑郁样行为。通过实时荧光定量PCR(Real-time fluorescence quantitative PCR,RT-qPCR)和蛋白免疫印迹(Western blotting)检测成年F1-UCMS小鼠海马LIM和SH3结构域蛋白1(LIM and SH3 domain protein 1,LASP1)的表达。结果与正常父系的F1子代(F1-Nor)相比,应激父系的F1子代F1-UCMS小鼠在OFT的中央区域停留时间百分比减少、EPM的开放臂停留时间百分比减少(P均<0.05),表现出明显焦虑样行为;F1-UCMS组小鼠在FST的不动时间百分比增加、SPT的糖水消耗百分比减少(P均<0.01),表现出明显抑郁样行为。与SE组相比,EE组小鼠在OFT的中央区域停留时间百分比增加[雄性:(7.44±0.75)%vs.(14.93±1.74)%,P<0.01;雌性:(8.89±1.06)%vs.(15.10±1.82)%,P<0.05]、EPM的开放臂停留时间百分比增加[雄性:(8.09±1.05)%vs.(14.15±1.88)%,P<0.05;雌性:(9.13±1.14)%vs.(14.04±1.37)%,P<0.05],表明EE改善父系应激导致的F1-UCMS小鼠焦虑样行为;EE组小鼠在FST的不动时间百分比减少[雄性:(58.63±4.51)%vs.(42.15±3.81)%,P<0.05;雌性:(57.96±4.19)%vs.(43.25±4.22)%,P<0.05]、SPT的糖水消耗百分比增加[雄性:(50.38±3.47)%vs.(70.39±3.12)%,P<0.01;雌性:(52.42±2.84)%vs.(69.99±3.55)%,P<0.01],表明EE改善父系应激导致的F1-UCMS小鼠抑郁样行为。RT-qPCR及Western blotting检测结果显示,与F1-Nor组相比,SE组子代小鼠海马LASP1表达减少(雄性P<0.01,雌性P<0.05);与SE组相比,EE组小鼠海马LASP1表达增加(P均<0.05)。结论EE可改善父系应激导致的F1-UCMS小鼠焦虑、抑郁样行为,其机制可能与F1-UCMS小鼠海马LASP1表达增加相关。

Objective To explore the role of environmental enrichment(EE)in paternal stress-induced anxiety and depression-like behaviors in offspring and its potential mechanisms.Methods Male C57BL/6 mice(F0)were treated with unpredictable chronic mild stress(UCMS)and subsequently mated with normal females to obtain F1 offspring mice.The standard environment(SE)and enriched environment(EE)were administered to F1-UCMS offspring mice during their early life(3-5 weeks of age).Anxiety-like behaviors were detected by open field test(OFT)and elevated plus-maze test(EPM);depression-like behaviors were detected via forced swimming test(FST)and sucrose preference test(SPT)at the age of 8 weeks.The expressions of LIM and SH3 domain protein 1(LASP1)in the hippocampus of adult F1 offspring mice were detected by Real-time fluorescence quantitative PCR(RT-qPCR)and Western blotting.Results Compared to F1 offspring of normal paternal(F1-Nor),F1 offspring mice of the stressed paternal(F1-UCMS)showed significantly anxiety-like behavior with reduced percentage of time spent in the central region of OFT and in the open arm of EPM(P<0.05);mice from the F1-UCMS group showed a significantly increased percentage of immobility in FST and a reduced percentage of sugar consumption in SPT(P<0.01),which demonstrated significant depression-like behaviors.Compared to the SE group,mice in the EE group had an increased percentage of time spent in the central region of the OFT[males:(7.44±0.75)%vs.(14.93±1.74)%,P<0.01;females:(8.89±1.06)%vs.(15.10±1.82)%,P<0.05]and an increased percentage of time in the open arm of EPM[males:(8.09±1.05)%vs.(14.15±1.88)%,P<0.05;females:(9.13±1.14)%vs.(14.04±1.37)%,P<0.05].This indicated that EE ameliorated anxiety-like behavior in F1-UCMS mice with paternal stress.Compared to the SE group,mice in the EE group had an decreased percentage of immobility in FST[males:(58.63±4.51)%vs.(42.15±3.81)%,P<0.05;females:(57.96±4.19)%vs.(43.25±4.22)%,P<0.05]and an increased percentage of sugar consumption in SPT[males:(50.38±3.47)%vs.(70.39±3.12)%,P<0.01;females:(52.42±2.84)%vs.(69.99±3.55)%,P<0.01].This indicated that EE ameliorated depression-like behavior in F1-UCMS mice with paternal stress.Hippocampal LASP1 expression was reduced in SE group compared to F1-Nor group(males:P<0.01;females:P<0.05),while LASP1 was increased in EE group compared to SE group(P<0.05)detected by RT-qPCR and Western blotting.Conclusion EE ameliorates paternal stress-induced anxiety and depression-like behaviors in F1-UCMS mice,and the mechanism may be associated with increased hippocampal LASP1 expression in F1-UCMS mice.