Effect of ω-3 polyunsaturated fatty acids and ω-6 polyunsaturated acids on Toll-like receptor /nuclear fac-tor-κB signaling pathway and the inflammatory cytokines in neonatal rats with brain injury induced by lipopolysaccharide / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the effects of ω-3 polyunsaturated fatty acids(ω-3PUFAs)and ω-6 polyunsaturated fatty acids(ω-6PUFAs)on Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB)signaling pathway,and the expressions of tumor necrosis factor-α(TNF-α),interleukin(IL)-1β and IL-6 in neonatal rats with brain injury induced by lipopolysaccharide (LPS). Methods Ninety-six neonatal rats were divided into control group,ω-3PUFAs group,ω-6PUFAs group,and LPS group by using random number table method. Intraperitoneal injection of LPS was performed in LPS group,ω-6PUFAs group and ω-3PUFAs group to establish models of rat brain injury. The rats in control group received 9 g/L saline. Twelve newborn rats were killed at 1 d or 5 d after intraperito-neal injection in each group for hippocampus selection. Real -time PCR and Western blot were used to detect the mRNA and protein expression levels of TLR4,NF-κB,TNF-α,IL-1β and IL-6. Results One day after mode-ling,TLR4,NF-κB,TNF-α,IL-1β and IL-6 mRNA expressions in ω-3PUFAs group (10. 63 ± 0. 07,5. 86 ± 1. 05,7. 65 ± 2. 29,5. 23 ± 1. 31,3. 36 ± 0. 72)were lower than those in ω-6PUFAs group (18. 83 ± 2. 10,8. 79 ± 2. 08,11. 95 ± 3. 23,10. 97 ± 2. 24,6. 37 ± 1. 17)and LPS group (15. 76 ± 1. 59,7. 13 ± 1. 10,9. 71 ± 2. 14,7. 83 ± 0. 85,4. 78 ± 0. 51),and the differences were all statistically significant(all P＜0. 05);which in ω-6PUFAs group were higher than those in LPS group,and the differences were all significant (all P＜0. 05). TLR4,NF-κB,TNF-α, IL-1β and IL-6 protein levels in ω-3PUFAs group (1. 57 ± 0. 11,1. 58 ± 0. 09,1. 55 ± 0. 09,1. 63 ± 0. 31,1. 36 ± 0. 12)were lower than those in ω-6PUFAs group (1. 96 ± 0. 17,2. 21 ± 0. 12,1. 95 ± 0. 23,1. 97 ± 0. 24,1. 77 ± 0. 17)and LPS group (1. 73 ± 0. 15,1. 87 ± 0. 10,1. 79 ± 0. 14,1. 83 ± 0. 15,1. 58 ± 0. 11)in 1 d,and the diffe-rences were all significant (all P＜0. 05),and those in ω-6PUFAs group were higher than those in LPS group (all P＜0. 05). Similarly,TLR,NF-κB,TNF-α,IL-1β and IL-6 mRNA and protein expression levels in ω-3PUFAs group (3. 78 ± 0. 88,3. 86 ± 0. 62,6. 26 ± 1. 94,3. 65 ± 1. 44,2. 11 ± 0. 87;1. 15 ± 0. 08,1. 32 ± 0. 10,1. 46 ± 0. 04, 1. 38 ± 0. 14,1. 21 ± 0. 09)were lower than those in ω-6PUFAs group (7. 76 ± 1. 65,5. 51 ± 0. 88,7. 96 ± 2. 13,5. 35 ± 1. 75,4. 88 ± 1. 35;1. 42 ± 0. 15,1. 51 ± 0. 36,1. 65 ± 0. 13,1. 72 ± 0. 23,1. 48 ± 0. 10)and LPS group (6. 21 ± 1. 87, 4. 98 ± 0. 73,7. 11 ± 2. 10,4. 84 ± 1. 75,4. 25 ± 0. 64;1. 35 ± 0. 13,1. 44 ± 0. 22,1. 59 ± 0. 10,1. 61 ± 0. 18,1. 35 ± 0. 07) in 5 d (all P＜0. 05),and which in ω-6PUFAs group were higher than those in LPS group,and the differences were sig-nificant (all P＜0. 05). Conclusion ω-6PUFAs can up-regulate the activity of TLR4,NF-κB,and reduce the re-lease of TNF-α,IL-1β and IL-6;and ω-3PUFAs can down-regulate the activity of TLR4,NF-κB,and reduce the release of TNF-α,IL-1β and IL-6,so it has a neural protective effect in brain injury induced by LPS.