Ursolic acid improved demyelination and interstitial fluid drainage disorders in schizophrenia mice
10.19723/j.issn.1671-167X.2024.03.016
- VernacularTitle:熊果酸改善精神分裂症小鼠脱髓鞘和脑组织间液引流紊乱
- Author:
Ren LONG
1
;
Xin MAO
;
Tianzi GAO
;
Qian XIE
;
Hanbo TAN
;
Ziyin LI
;
Hongbin HAN
;
Lan YUAN
Author Information
1. 北京大学医学技术研究院医学影像技术学系,北京市磁共振成像设备与技术重点实验室,北京 100191
- Keywords:
Schizophrenia;
Brain interstitial fluid;
Demyelination;
Ursolic acid
- From:
Journal of Peking University(Health Sciences)
2024;56(3):487-494
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To unveil the pathological changes associated with demyelination in schizophre-nia(SZ)and its consequential impact on interstitial fluid(ISF)drainage,and to investigate the thera-peutic efficacy of ursolic acid(UA)in treating demyelination and the ensuing abnormalities in ISF drainage in SZ.Methods:Female C57BL/6J mice,aged 6-8 weeks and weighing(20±2)g,were randomly divided into three groups:control,SZ model,and UA treatment.The control group received intraperitoneal injection(ip)of physiological saline and intragastric administration(ig)of 1％carboxy-methylcellulose sodium(CMC-Na).The SZ model group was subjected to ip injection of 2 mg/kg dizo-cilpine maleate(MK-801)and ig administration of 1％CMC-Na.The UA treatment group underwent ig administration of 25 mg/kg UA and ip injection of 2 mg/kg MK-801.The treatment group received UA pretreatment via ig administration for one week,followed by a two-week drug intervention for all the three groups.Behavioral assessments,including the open field test and prepulse inhibition experiment,were conducted post-modeling.Subsequently,changes in the ISF partition drainage were investigated through fluorescent tracer injection into specific brain regions.Immunofluorescence analysis was employed to examine alterations in aquaporin 4(AQP4)polarity distribution in the brain and changes in protein expres-sion.Myelin reflex imaging using Laser Scanning Confocal Microscopy(LSCM)was utilized to study modifications in myelin within the mouse brain.Quantitative data underwent one-way ANOVA,followed by TukeyHSD for post hoc pairwise comparisons between the groups.Results:The open field test re-vealed a significantly longer total distance[(7 949.39±1 140.55)cm vs.(2 831.01±1 212.72)cm,P＜0.001]and increased central area duration[(88.43±22.06)s vs.(56.85±18.58)s,P=0.011]for the SZ model group compared with the controls.The UA treatment group exhibited signifi-cantly reduced total distance[(2 415.80±646.95)cm vs.(7 949.39±1 140.55)cm,P＜0.001]and increased central area duration[(54.78±11.66)s vs.(88.43±22.06)s,P=0.007]compared with the model group.Prepulse inhibition test results demonstrated a markedly lower inhibition rate of the star-tle reflex in the model group relative to the controls(P＜0.001 for both),with the treatment group dis-playing significant improvement(P＜0.001 for both).Myelin sheath analysis indicated significant demy-elination in the model group,while UA treatment reversed this effect.Fluorescence tracing exhibited a significantly larger tracer diffusion area towards the rostral cortex and reflux area towards the caudal thala-mus in the model group relative to the controls[(13.93±3.35)mm2 vs.(2.79±0.94)mm2,P＜0.001 for diffusion area;(2.48±0.38)mm2 vs.(0.05±0.12)mm2,P＜0.001 for reflux area],with sig-nificant impairment of drainage in brain regions.The treatment group demonstrated significantly reduced tracer diffusion and reflux areas[(7.93±2.48)mm2 vs.(13.93±3.35)mm2,P＜0.001 for diffusion area;(0.50±0.30)mm2 vs.(2.48±0.38)mm2,P＜0.001 for reflux area].Immunofluorescence staining revealed disrupted AQP4 polarity distribution and reduced AQP4 protein expression in the model group compared with the controls[(3 663.88±733.77)μm2 vs.(13 354.92±4 054.05)μm2,P＜0.001].The treatment group exhibited restored AQP4 polarity distribution and elevated AQP4 protein expression[(11 104.68±3 200.04)μm2 vs.(3 663.88±733.77)μm2,P＜0.001].Conclusion:UA intervention ameliorates behavioral performance in SZ mice,Thus alleviating hyperactivity and anxiety symptoms and restoring sensorimotor gating function.The underlying mechanism may involve the improve-ment of demyelination and ISF drainage dysregulation in SZ mice.
