益脉康片对放射性脑损伤小鼠保护作用及机制研究

Protective effects and main mechanism of Yimaikang tablet on radiation-induced brain injury in mice

目的探讨益脉康片对放射性脑损伤小鼠的保护作用及主要作用机制。方法将50只BALB/c小鼠随机分为对照组、模型组和益脉康片低、中、高剂量(4.30、8.61、17.22 mg/kg)组,采用伽玛刀对除对照组外其余各组小鼠进行造模,连续7 d。造模结束后,益脉康片组ig给药,对照组及模型组给予等量生理盐水,连续给药2周,1次/d。末次给药24 h后,采用Morris法检测各组小鼠的学习及记忆能力,并对各组小鼠海马体CA1区进行TUNEL染色及尼氏染色,采用免疫组化法检测各组小鼠兔抗烟酰胺腺嘌呤二核苷酸磷酸酶氧化酶(NOX4)的表达情况,并对其进行半定量分析。结果第2～5天,对照组和益脉康片低、中、高剂量组潜伏期均明显低于模型组(P<0.05);与模型组比较,对照组和益脉康片低、中、高剂量组第Ⅲ象限时间及穿越平台次数均明显增加(P<0.05);尼氏染色中,与模型组比较,益脉康片低、中、高剂量小鼠海马体中神经细胞核核仁不清晰及细胞形态异常程度均明显减轻;TUNEL染色中,与模型组比较,益脉康片低、中、高剂量组均仅有呈散在的少量阳性染色神经元;免疫组化中,与模型组比较,益脉康片低、中、高剂量组中NOX4阳性染色均明显弱于模型组,且相对表达量均明显低于模型组(P<0.05)。结论益脉康片对放射性脑损伤小鼠具有较好的保护作用,其作用机制可能与有效抑制小鼠海马体中NOX4表达有关。

Objective To study the protective effects and main mechanism of Yimaikang tablet on radiation-induced brain injury in mice.Methods A total of 50 BALB/c mice were divided into control group,model group,and Yimaikang tablet low,middle and high dose(4.30,8.61,and 17.22 mg/kg)treatment groups.The gamma knife was used to establish the radiation-induced brain injury model for continuous 7 d.After the modeling,mice in Yimaikang tablet group were ig administrated corresponding drugs,the other groups were treated by equivalence saline,lasted 2 weeks,once per day.24 hours after the last gavage,the Morris method was used to test the learning and memory ability of mice in each group.The TUNEL staining and Nissl’s staining were performed on hippocampus CA1 region of mice.The immunohistochemical method was performed to observe the expression of NOX4 in mice,and the semi-quantitative analysis was also carried out.Results In the training of 2—5 d,the incubation periods of control group and low,middle,and high dose groups of Yimaikang tablet were significantly lower than model group(P<0.05);Compared with the model group,the third quadrant residence time and times of crossing the platform in control group and Yimaikang tablet groups were significantly increased(P<0.05).The TUNEL staining showed that there were small numbers of positive staining neurons in Yimaikang tablet groups when compared with the model group.The Nissl’s staining showed that,compared with the model group,the cell morphological abnormalities and nucleoli blurring of neurocytes in the hippocampus of mice were significantly alleviated in low,middle,and high dose groups of Yimaikang tablet.From the results of immunohistochemical analysis,we found that the NOX4 positive stainings in Yimaikang tablet groups were significantly less than the model group,and the relative expression were significantly lower than model group(P<0.05).Conclusion Yimaikang tablet has a good protective effects on radiation-induced brain injury in mice and the mechanism may be related to the effective inhibition of NOX4 expression in the hippocampus of mice.