Objectives

In this study, we aimed to verify the neuroprotective effects of pycnogenol (PYC) on spinal cord injury (SCI) and to determine the underlying mechanisms.

Methods

Male Wistar rats were selected to establish a model of SCI in accordance with the Allen’s protocol. The rats in the PYC group were treated with 100 mg/kg PYC by intraperitoneal injection 15 minutes after SCI. The Basso, Beattie and Bresnahan (BBB) scale was used to evaluate locomotor activity. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) production were detected by ELISA. The expression of Cleaved-caspase 3, Bcl-2, Bax and the levels of Cytochrome c (Cyt-c) were analysed by Western blot or Immunohistochemistry. Furthermore, we used the JC-1 fluorescent probe to analyse the mitochondrial membrane potential (ΔΨm).

Results

The rats that received PYC had significantly higher BBB scores than the control lesion rats. PYC treatment resulted in reduced bleeding in spinal cord tissue and proliferation of glial cells, greater numbers of anterior horn neurons, more complete structures of residual neurons, and significant improvement in Nissl body morphology. In addition, PYC reduced MDA production and increased SOD activity. The mitochondrial membrane potential (MMP) was significantly increased in the PYC treatment group compared with the SCI group. In addition, PYC decreased the expression of Cleaved-caspase 3 and Bax and the release of Cyt-c and increased the expression of Bcl-2 in the SCI rats.

Conclusions

The above findings suggested that PYC can improve motor function and reduce neuronal apoptosis after SCI by stabilizing the MMP through the inhibition of oxidative stress.

Abbreviations

DMSO: dimethyl sulfoxide; IHC: immunological histological chemistry; MDA: malondialdehyde; PBS: phosphate buffered saline; PMSF: phenylmethanesulfonyl fluoride; PVDF: polyvinylidene difluoride; PYC: Pycnogenol; RIPA: radio immunoprecipitation assay; SCI: spinal cord injury; SOD: superoxide dismutase

中文翻译：

---

碧萝ogen可通过稳定线粒体膜电位，在脊髓损伤大鼠中实现神经保护作用。

目标

在这项研究中，我们旨在验证碧萝ogen（PYC）对脊髓损伤（SCI）的神经保护作用，并确定其潜在机制。

方法

根据Allen的方案，选择雄性Wistar大鼠以建立SCI模型。在SCI后15分钟，通过腹膜内注射以100 mg / kg PYC处理PYC组的大鼠。Basso，Beattie和Bresnahan（BBB）量表用于评估运动能力。通过ELISA检测超氧化物歧化酶（SOD）活性和丙二醛（MDA）产生。通过蛋白质印迹或免疫组织化学分析了Cleaved-caspase 3，Bcl-2，Bax的表达和细胞色素c（Cyt-c）的水平。此外，我们使用JC-1荧光探针分析线粒体膜电位（ΔΨm）。

结果

接受PYC的大鼠的BBB评分明显高于对照组。PYC治疗可减少脊髓组织的出血和神经​​胶质细胞的增殖，增加前角神经元的数量，残留神经元的结构更加完整，并显着改善Nissl身体形态。此外，PYC减少了MDA的产生并增加了SOD活性。与SCI组相比，PYC治疗组的线粒体膜电位（MMP）显着增加。此外，PYC降低了SCI大鼠Cleaved-caspase 3和Bax的表达以及Cyt-c的释放，并增加了Bcl-2的表达。

结论

上述发现表明，PYC可以通过抑制氧化应激来稳定MMP，从而改善SCI后的运动功能并减少神经元凋亡。

缩略语

DMSO：二甲基亚砜；IHC：免疫组织化学；MDA：丙二醛；PBS：磷酸盐缓冲盐水；PMSF：苯基甲磺酰氟；PVDF：聚偏二氟乙烯；PYC：碧萝ogen；RIPA：放射免疫沉淀分析；SCI：脊髓损伤；SOD：超氧化物歧化酶