Effect of 3 neuroprotective measures on expressions of Fas/FasL in brain tissue of neonatal rats with hypoxicischemic brain damage / 中国中西医结合急救杂志

ABSTRACT

Objective To observe the effects of 3 neuroprotective measures on the expressions of apoptosis-related factors and their ligands (Fas and FasL) in brain tissue of neonatal rats with hypoxic ischemic brain injury. Methods One hundred and twenty Wistar rats 7 days old were selected as experimental subjects, the rats were divided into four groups neural stem cell, erythropoietin (EPO), ω-3 unsaturated fatty acid treatment groups and hypoxic ischemic brain damage model group according to random number table method, with 30 rats in each group. Neural stem cell group, EPO group and ω-3 unsaturated fatty acid group were respectively injected with neural stem cells, EPO and ω-3 unsaturated fatty acid, each 5 mL via tail vein after modeling; the hypoxic ischemic brain damage model group was given equal volume of normal saline. At 6, 12, 24, 48 and 72 hours after administration of drug, 6 rats were sacrificed in each group, brain tissue was taken, the mRNA expression levels of Fas/FasL, protein expression levels of Toll-like receptor 4 (TLR4), nuclear transcription factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), interleukin (IL-1β, IL-6) and cell apoptotic rate in hippocampus tissue were measured. Results ① mRNA expressions the mRNA expressions of Fas and FasL of the 3 experimental groups were significantly lower than those of the hypoxic ischemic brain damage model group, the degrees of descent after administration for 24 hours were the most significant, neural stem cell treatment group < EPO treatment group < ω-3 unsaturated fatty acid treatment group < hypoxic ischemic brain damage model group [Fas mRNA expression (2-&Delta;&Delta;Ct) 140.5±2.9, 156.4±2.5, 165.2±2.7 vs. 173.7±2.8, FasL mRNA expression (2-&Delta;&Delta;Ct) 143.1±4.3, 154.6±1.5, 160.7±1.4 vs. 174.7±2.8], the differences were statistically significant (all P < 0.05). ② Protein expressions the protein expressions of TLR4, NF-κB, TNF-α, IL-1β, IL-6 of the 3 experimental groups were significantly lower than those of the hypoxic ischemic brain damage model group (TLR4/GAPDH 0.7±0.2, 0.6±0.1, 0.2±0.1 vs. 1.4±0.1; NF-κB/GAPDH 6.7±0.4, 5.3±0.1, 1.1±0.2 vs. 11.2±0.3; TNF-α/GAPDH 14.3±1.4, 11.2±1.2, 3.2±2.1 vs. 23.2±0.5; IL-1β/GAPDH 9.4±0.2, 7.4±0.3, 2.2±0.3 vs. 13.4±0.1; IL-6/GAPDH 36.2±4.4, 39.3±1.5, 26.2±2.1 vs. 51.4±1.4, all P < 0.05), the protein expression levels of above indexes in neural stem cell treatment group < those of EPO treatment group < those of ω-3 unsaturated fatty acid treatment group < those of hypoxic ischemic brain damage model group. ③ Apoptotic ratesafter drug administration, the apoptotic rates of the ω-3 unsaturated fatty acid group, EPO treatment group, neural stem cell treatment group were obviously lower than the rate of model group [(3.7±0.3)%, (3.4±0.2)%, (2.5±0.1)% vs. (5.5±0.4)%, all P < 0.05]. Conclusion The mRNA expressions of Fas/FasL in the brain of neonatal rats with hypoxic-ischemic brain damage are high, and the treatment with each of the following agents; neural stem cells, EPO and ω-3 unsaturated fatty acid can reduce the mRNA expressions of Fas/FasL in such rats' brain tissues.