新生儿缺氧缺血性脑病血清脑脊液中胰岛素样生长因子-Ⅱ水平的变化

目的：很多研究都证实低水平的胰岛素样生长因子-Ⅰ(IGF-Ⅰ)与缺氧缺血性脑损伤的发生有关,认为IGF-Ⅰ具有重要的神经保护作用。胰岛素样生长因子-Ⅱ(IGF-Ⅱ)在结构及功能上与IGF-Ⅰ具有同源性,但对其在脑损伤中的作用尚不明了。该研究通过观察新生儿缺氧缺血性脑病(HIE)血清、脑脊液中IGF-Ⅱ水平的变化,探讨IGF-Ⅱ在新生儿HIE发病机制及预后中的作用。方法：用放射免疫法(RIA)检测41例HIE新生儿在急性期和恢复期血清、脑脊液及10例正常足月新生儿(对照组)血清中IGF-Ⅱ的水平变化。结果：在急性期,轻、中度HIE组血清IGF-Ⅱ分别为203.28±40.09ng/mL,192.33±39.66ng/mL,较对照组的229.38±43.39ng/mL无显著性降低(P>0.05);重度HIE组血清IGF-Ⅱ水平为116.72±39.50ng/mL较轻、中度HIE组及对照组明显降低(P<0.01)。在恢复期,轻、中度HIE组及重度HIE症状恢复组血清中IGF-Ⅱ分别为285.53±49.44ng/mL;278.69±51.34ng/mL;254.08±48.50ng/mL,脑脊液中分别为81.58±9.77ng/mL;78.48±10.44ng/mL;69.42±10.20ng/mL,较急性期时的27.23±7.82ng/mL,23.43±7.79ng/mL,15.05±7.03ng/mL水平明显增高(P<0.01);重度HIE症状未恢复组血清、脑脊液IGF-Ⅱ分别为144.64±46.30ng/mL;25.05±784ng/mL,虽较急性期增高,但差异无显著性意义(P>0.05),且明显低于其他各组的水平(P<0.01)。HIE组血清与脑脊液间的IGF-Ⅱ水平存在明显的正相关关系(r=0.69,P<0.01)。结论：血和脑脊液中IGF-Ⅱ水平的改变与新生儿HIE的发生及转归有关。

Changes of serum and cerebrospinal fluid insulin like growth factor-II levels in neonates with hypoxic-ischemic encephalopathy

OBJECTIVE: Many studies have demonstrated that low levels of insulin-like growth factor-I (IGF-I) may be associated with the hypoxic-ischemic brain damage (HIBD) and that IGF-I has a neuroprotective effect. The role of IGF-II, a structurally and functionally homologous polypeptide with IGF-I, is unclear in HIBD. This study was designed to observe the changes of serum and cerebrospinal fluid (CSF) IGF-II levels in neonates with hypoxic-ischemic encephalopathy (HIE) and to investigate its effects on HIE. METHODS: Serum and CSF IGF-II levels in 41 neonates with HIE were measured by radioimmunoassay in the acute phase (postnatal age 12-24 hrs) and the convalescence phase (postnatal age 10-12 days). The 41 HIE neonates included 10 cases of mild, 12 moderate, and 19 severe HIE. Serum samples of 10 normal neonates were used as controls. RESULTS: In the acute phase, serum IGF-II levels in the Mild HIE group (203.28 +/- 40.09 ng/mL) and the Moderate HIE group (192.33 +/- 39.66 ng/mL) were not significantly reduced, but were obviously reduced in the Severe HIE group (116.72 +/- 39.50 ng/mL) compared with normal controls (229.38 +/- 43.39 ng/mL) (P<0.01). During the convalescence phase, serum IGF-II levels in the Mild HIE group (285.53 +/- 49.44 ng/mL) and in the Moderate HIE group (278.69 +/- 51.34 ng/mL) increased significantly (P < 0.01); CSF IGF-II levels increased in the Mild HIE group from 27.23 +/- 7.82 ng/mL (acute phase) to 81.58 +/- 9.77 ng/mL (convalescence phase) (P < 0.01) and also increased in the Moderate HIE group from 23.43 +/- 7.79 ng/mL (acute phase) to 78.48 +/- 10.44 ng/mL (convalescence phase) (P < 0.01). The patients from the severe HIE group whose neurological symptoms or signs were improved in the convalescence showed higher serum and CSF IGF-II levels than in the acute phase (254.08 +/- 48.50 ng/mL vs 122.21 +/- 46.26 ng/mL; 69.42 +/- 10.20 ng/mL vs 15.05 +/- 7.03 ng/mL; P < 0.01). A positive correlation was found between the serum and CSF IGF-II levels in the HIE group (r=0.69, P < 0.01). CONCLUSIONS: IGF-II levels in serum and CSF are associated with the pathogenesis and the prognosis of neonatal HIE.