Central nervous system-targeted reactivator HI-6 lipid nanoparti-cles for salvage of organophosphorus-induced brain injury mice
10.3867/j.issn.1000-3002.2025.08335
- VernacularTitle:中枢靶向重活化剂酰胺磷定脂质纳米颗粒对有机磷脑损伤小鼠的救治研究
- Author:
Ruizhi LIN
1
;
Jianyu WANG
;
Yajing WEI
;
Xinran ZHAO
;
Lin WANG
;
Jun YANG
;
Yongan WANG
;
Cuiyun YU
Author Information
1. 南华大学药学院,湖南 衡阳 421001;军事医学研究院,北京 100850
- Publication Type:Journal Article
- Keywords:
organophosphorus compounds;
lipid nanoparticles;
reactivation;
phospholipase A2;
blood-brain barrier;
asoxime
- From:
Chinese Journal of Pharmacology and Toxicology
2025;39(9):641-650
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE To construct novel central nervous system(CNS)-targeted lipid nanoparti-cles for the treatment of organophosphorus-induced brain injury in mice.METHODS(1)Preparation,screening,and characterization of lipid nanoparticles.① Lipid nanoreactivators were prepared using the thin-film hydration method,with asoxime(HI-6)as the therapeutic drug and lipid carriers composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine(POPS),1,2-dipalmitoyl-sn-glycero-3-phospho-choline(DPPC),and cholesterol(CHOL)(PDC)at varying molar ratios(1∶6∶3,3∶4∶3,5∶2∶3 and 7∶0∶3)(HI-6@PDC 1∶6∶3,3∶4∶3,5∶2∶3 and 7∶0∶3).② FLU-labeled lipid nanocarriers(FLU@PDC 1∶6∶3,3∶4∶3,5∶2∶3,and 7∶0∶3)were prepared and physically mixed with phospholipase A2(PLA2)solution(at the final PLA2 concentration of 10 kU·L-1)to obtain FLU@PDC+PLA2.Male KM mice were randomly divided into normal control(PBS),FLU,and FLU@PDC+PLA2(1∶6∶3,3∶4∶3,5∶2∶3,and 7∶0∶3)groups(n=7 per group).After intravenous(iv)administration(FLU dose:1 mg·kg-1,carrier dose:80 mg·kg-1),brain tissues were collected at 1 h,homogenized,centrifuged,and analyzed via fluorescence spectrophotom-etry to screen the optimal CNS-targeted lipid carrier composition.③ The morphology of HI-6@PDC 5∶2∶3 was characterized by transmission electron microscope(TEM).The particle size,polydispersity index(PDI),and zeta potential of HI-6@PDC 5∶2∶3 were measured using a Zeta potential and particle size analyzer.Encapsulation efficiency and loading efficiency of HI-6@PDC 5∶2∶3 were determined using an ultrafiltration centrifugation method combined with high-performance liquid chromatography(HPLC).In vitro release kinetics of HI-6@PDC 5∶2∶3 and HI-6@PDC+PLA2 5∶2∶3 were assessed using a dialysis bag diffusion method combined with fluorescence spectrophotometry.(2)Validation of CNS targeting.① Cyanine7(Cy7)-labeled PDC 5∶2∶3(Cy7@PDC)was prepared and mixed with PLA2 solution(Cy7@PDC+PLA2 5∶2∶3).Mice were divided into normal control,Cy7,Cy7@PDC 5∶2∶3 and Cy7@PDC+PLA2 5∶2∶3 groups(n=3 per group).After iv injection(Cy7 dose:1 mg·kg-1,carrier dose:80 mg·kg-1),brain fluorescence was visualized at 3 h using a small animal in vivo imaging(IVIS)system.② Cyanine 3(Cy3)-labeled PDC 5∶2∶3(Cy3@PDC 5∶2∶3)was prepared and mixed with PLA2 solution(Cy3@PDC+PLA2 5∶2∶3).Mice were divided into Cy3@PDC 5∶2∶3 and Cy3@PDC+PLA2 5∶2∶3 groups(n=3 per group).After iv injection(Cy3 dose:1 mg·kg-1,carrier dose:80 mg·kg-1),brain tissues were collected at 2 h for fluorescent staining and Cy3 fluorescence observation.(3)Therapeutic efficacy eval-uation.① Male KM mice were randomly divided into normal control,brain injury,HI-6 treatment,and HI-6@PDC+PLA2 5∶2∶3 treatment groups(n=6 per group).Except for the normal control,all the mice were subcutaneously(sc)injected with soman(120 μg·kg-1),followed by immediate iv treatment(HI-6 dose:22 mg·kg-1,carrier dose:80 mg·kg-1).At 10 min,orbital blood and brain tissues were collected before brain weight was recorded.Acetylcholinesterase(AChE)reactivation in blood and brain was measured using the Ellman method.② Grouping and treatment were identical to ①(n=3 per group).At 24 h,brain tissues were collected for HE staining to assess histopathological damage.③ Mice were divided into brain injury and HI-6@PDC+PLA2 5∶2∶3 treatment groups(n=10 per group)and treated as in ①(soman dose:220 ug·kg-1).Survival rates,neurotoxic symptoms(tremors,salivation),and seizure latency were recorded,and survival curves were plotted.RESULTS(1)PDC 5∶2∶3 exhibited the highest brain fluorescence,indicating optimal CNS targeting.HI-6@PDC 5∶2∶3 appeared in regular spherical shapes,and were negatively charged,with a size of(219.4±3.1)nm,PDI of 0.4±0.02,entrapment effi-ciency of 72.9％and loading efficiency of 49.7％.HI-6@PDC+PLA2 5∶2∶3 showed a cumulative release of 43.5％at 60 min,which was lower than that of rhodamine B(RB)but sufficient for CNS therapeutic timelines.(2)In vivo fluorescence and pathological fluorescence confirmed PLA2-mediated CNS delivery.(3)HI-6@PDC+PLA2 5∶2∶3 significantly enhanced AChE reactivation in the blood and brain compared to HI-6.Histopathology revealed mitigated brain injury in treated mice.HI-6@PDC+PLA2 5∶2∶3 prolonged survival,reduced convulsions,alleviated neurotoxicity,and extended seizure latency.CONCLUSION HI-6@PDC 5∶2∶3 can effectively cross the blood-brain barrier via PLA2 mediation,demonstrating strong CNS targeting.It can significantly improve AChE reactivation in peripheral and central tissues and offers potent therapeutic efficacy against organophosphate-induced brain injury.
