摘要目的 探究支气管哮喘(哮喘)合并焦虑小鼠模型大脑中神经肽S含量的变化,并在体外实验研究炎性因子对神经元分泌神经肽S的影响.方法 将40只BALB/C小鼠按随机数字表法随机分为对照组、哮喘组、焦虑组以及哮喘合并焦虑组,实时荧光定量PCR法检测各组动物模型脑组织中神经肽S mRNA相对表达量;体外原代培养大鼠大脑皮层神经元细胞,分为磷酸盐缓冲液(PBS)对照组、IL-1β组、IL-6组和肿瘤坏死因子(TNF)-α组,用炎性因子刺激神经元后,QRT-PCR法检测各组神经肽S mRNA表达水平,ELISA法检各组细胞培养液中神经肽S的含量.结果 各组动物模型大脑中神经肽S mRNA的相对表达量,焦虑组(0.88 ±0.05)和哮喘合并焦虑组(0.79 ±0.03)明显低于对照组(1.01 ±0.05)和哮喘组(0.96±0.06),并且哮喘合并焦虑组明显低于其他3组,差异均有统计学意义(均P ＜0.05).IL-6组和TNF-α组神经肽S mRNA相对表达量分别为0.88±0.07和0.86±0.07,均明显低于PBS对照组(1.00±0.06)和IL-1β组(0.94 ±0.08),差异均有统计学意义(均P＜0.05);IL-1β组神经肽S mRNA相对表达量与PBS对照组相比,差异无统计学意义(t=-1.81,P=0.079).IL-6组和TNF-α组培养液中神经肽S含量分别为(45.4±1.2) ng/L和(46.0±1.0) ng/L,均明显低于PBS对照组的(50.6±1.8) ng/L和IL-1β组的(49.5±1.0) ng/L,差异均有统计学意义(均P＜0.05);IL-1β组培养液中神经肽S含量与PBS对照组相比,差异无统计学意义(t=-1.89.P=0.067).结论 哮喘血清中升高的IL-6、TNF-α可抑制神经元细胞分泌神经肽S,具有抗焦虑作用的神经肽S含量下降,易导致焦虑的发生,这可能是哮喘与焦虑共病的机制之一.

abstractsObjective To investigate the levels of neuropeptide S in the brain of asthmatic mice with anxiety and the effects of inflammatory mediatores on changes of neuropeptide S in in vitro experiments.Methods According to the random number table method,40 BALB/C mice were randomly divided into 4 groups:the control group,the asthma group,the anxiety group and the asthma and anxiety group.The relative expressions of neuropeptidc S mRNA in the brain tissue of each group were detected by quantitative real-time polymerase chain reaction (QRT-PCR).Rat cortex neurons obtained by primary culture were divided into 4 groups:the PBS control group,the interleukin-1 beta group,the interleukin-6 group and the tumor necrosis factor-alpha group.After stimulation with inflammatory cytokines the mRNA expressions of neuropeptide S were measured by QRT-PCR and neuropeptide S levels in the cell culture supernatants were measured by emzyme linked immunosorbent assay (ELISA).Results The relative expressions of neuropeptide S mRNA were decreased in the anxiety group(0.87 ± 0.05) and the asthma and anxiety group (0.79 ± 0.03) compared with the control group (1.00 ± 0.05) and the asthma group (0.96 ± 0.06),most notably in the asthma and anxiety group (all P ＜ 0.05).Compared to the PBS control group [(1.00 ±0.06),(50.6 ± 1.8) ng/L] and the interleukin-1 beta group [(0.94 ± 0.08),(49.5 ± 1.0) ng/L],the levels of neuropeptide S mRNA and neuropeptide S were decreased in the interleukin-6 group [(0.88 ± 0.07),(45.4 ± 1.2) ng/L] and the tumor necrosis factor-alpha group [(0.86 ± 0.07),(46.0 ± 1.0) ng/L] (all P ＜ 0.05).There were no significant differences between the interleukin-1 beta group and the PBS control group(all P ＞ 0.05).Conclusions Up-regulated interleukin-6 and tumor necrosis factor-alpha in asthma can inhibit the secretion of neuropeptide S in neuronal cells.The decline of brain neuropeptide S,which has anti-anxiety effect,may lead to the occurrence of anxiety,which may be a potential mechanism of comorbidity of asthma and anxiety.