Omega-3鱼油脂肪乳对缺氧缺血性脑损伤新生大鼠海马组织Toll样受体4和核因子κB的影响

Effect of Omega - 3 fish oil fat emulsion on the expression of Toll - like receptor 4 and nuclear factor - κB in the neonatal rats hippocampus after hypoxic - ischemic

目的探讨Omega-3鱼油脂肪乳对新生7日龄大鼠缺氧缺血性脑损伤是否具有保护作用。方法168只7日龄sD大鼠，按照随机数字表法分为4组，A组：假手术组；B组：Omega-3鱼油脂肪乳组；C组：普通脂肪乳组；D组：模型组，每组42只。按照Rice法制备新生大鼠缺氧缺血性脑损伤模型。于出生1d、3d、7d时取脑组织，Real—timePCR和Westernblot检测大鼠海马组织中Toll样受体4（TLR4）和核因子KB（NF—κB）mRNA及蛋白的表达量，TUNEL染色分别比较观察不同组问大鼠脑组织中细胞凋亡情况。结果3d时海马CAl区HE染色可见A组组织结构基本正常；D组细胞水肿较其他各组严重；1d时D组TLR4和NF-κB的mRNA和蛋白的表达量均高于A组（P均〈0．05）；3d时B组TLR4和NF—κB的mRNA（4．89±0．51，9．30±1．53）及蛋白（1．15±0．10，1．44±0．14）的表达量低于c组（17．58±2．50，20．13±1．00；2．56±0．10，2．82±0．09）和D组（15．94±2．52，26．21±3．00；2．34±0．11，4．51±0．36）（P均〈0．05），与A组（6．30±1．52，5．32±1．06；1．32±0．10，2．42±0．14）比较差异均无统计学意义（P均〉0．05）；7d时B组TLR4和NF-κB的mRNA及蛋白的表达量低于c组和D组（P均〈0．05），与A组比较差异均无统计学意义（P均〉0．05）；3d时脑组织凋亡细胞数：B组细胞凋亡数（13．67±2．52）少于c组（27．67±2．52）和D组（41．00±3．61），差异均有统计意义（P均〈0．05），与A组（6．00±2．00）比较差异无统计学意义（P〉0．05）。结论Omega．3鱼油脂肪乳能够减轻缺氧缺血脑损伤而发挥神经保护作用，其作用机制与下调TLR4、NF—KB表达和减少细胞凋亡有关。

Objective To discuss whether Omega- 3 fish oil fat emulsion has the potential protective mecha- nism for 7 - day - old rats with hypoxic - ischemic brain damage （HIBD）. Methods One hundred and sixty - eight 7 - day - old SD rats were randomly divided into 4 groups ： group A（ sham group） , group B（ Omega - 3 fish oil fat emul- sion group） , group C （normal fat emulsion group）, group D （modal group）, and there were 42 cases in each group. Neo- natal HIBD was induced by the method of Rice. Rats were sacrificed at 1 d,3 d and 7 d after the surgery. Hippocampus was removed for Real - time PCR and Western blot test to detect Toll - like receptor 4 （ TLR4 ） and nuclear factor - KB （ NF - κB ） mRNA and protein expression. TUNEL staining comparison was done among different groups to observe the number of cellular apoptosis. Results HE staining of hippocampus CA1 area in 3 d showed that brain tissues in group A maintained normal structures ; those in group D had much more brain cells with severe edema than other groups; TLR4 and NF - κB mRNA and protein expression levels in group D were higher than those in group A in 1 d （ all P 〈 0.05） ; TLR4 and NF - KB expression levels of mRNA and protein in group B （4.89 ~0.51,9.30 ~ 1.53;1.15 ± 0.10,1.44±0.14） were lower than those in group C （17.58 ± 2.50,20.13 ± 1. 00 ;2.56 ±0.10,2.82 ± 0.09 ） and group D （15.94 ±2.52,26.21 ±3.00;2.34 ±0.11,4.51 ±0.36） in 3 d （all P〈0.05） ,and compared with group A （6.30 ± 1.52,5.32 ±0.06 ; 1.32 ± 0.10,2.42 ± 0.14 ）, there was significant difference （ all P 〉 0.05 ） ; TLR4 and NF - KB mRNA and protein expression levels in group B were lower than those in group C and group D in 7 d（ all P 〈 0.05 ）, and compared with group A there was no significant difference （ all P 〉 O. 05 ）. The apoptotic cell number of brain tissues in 3 d：group B （13.67 ±2.52） were lower than those in group C （27.67 ±2.52） and group D （41.00 ± 3.61 ） （all P 〈 0.05 ）, and compared with the group A （6.00 ± 2.00）, the difference was not statistically significant （P 〉 0.05 ）. Conclusions Omega - 3 fish oil fat emulsion plays an important role in protecting neonatal rats with HIBD. The mechanisms were likely to reduce TLR4, NF - κB and cell apoptosis levels.