仙人掌多糖组分对大鼠脑片氧化应激损伤的保护作用

目的研究仙人掌多糖对H_2O_2所致大鼠大脑皮质和海马脑片氧化应激损伤是否有保护作用。方法大鼠离体皮质和海马脑片与2mmol·L-1H_2O_2共孵育30min造成脑片的氧化应激损伤,分别于加入H_2O_2前加入仙人掌多糖作用30min,与H2O2同时加入仙人掌多糖作用30min或在H2O2损伤之后加入仙人掌多糖作用2h。TTC染色法检测脑片活性,并检测脑片培养液中乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)活性,谷胱甘肽(GSH)含量和总抗氧化能力(T-AOC)。结果H2O2孵育30min明显损伤大鼠海马和皮质脑片,TTC染色A490nm值下降,LDH释放增加,GSH含量和总抗氧化能力降低。加入H_2O_2前预先加入仙人掌多糖0.333和1.67mg·L-1作用30min显著抑制上述H2O2所致脑片损伤,使受损脑片孵育液中GSH含量增加,SOD活性和总抗氧化能力升高。结论仙人掌多糖能够减轻H2O2所致大鼠大脑皮质和海马脑片的氧化应激损伤,其机制可能与其增强机体的抗氧化能力有关。

Protection of cactus polysaccharides against oxidative stress injury of rat brain slices

AIM To investigate if cactus polysaccharides（CP）protect rat cerebral cortical and hippocampal slices against oxidative stress injuries induced by H₂O₂. METHODS Rat cerebral cortex and hippocampus slices were prepared and incubated in artificial cerebrospinal fluid (ACSF)， then the slices were co-incubated with 2 mmol·L^-1 H₂O₂ for 30 min to cause oxidative stress injury. These slices were incubated with CP 0.333 and 1.67 mg·L^-1 during different duration, pre-incubated with H₂O₂ for 30 min, co-incubated with H₂O₂ for 30 min and post incubated with H₂O₂ for 2 h, respectively. Injury of brain slices was determined by TTC method. Lactate dehydrogenase (LDH), superoxide dismutase (SOD) activities, glutathion (GSH) content and total antioxidation capability (T-AOC) in incubation medium were detected. RESULTS Incubated with H₂O₂ 2 mmol·L^-1 for 30 min, rat cerebral cortical and hippocampal slices were significantly damaged, indicated by decreased A_{490 nm} value of TTC staining. Meanwhile, the release of LDH in supernatant increased, but GSH and T-AOC decreased. CP 0.333 and 1.67 mg·L^-1 pre-incubation for 30 min significantly inhibited the decrease in TTC value and the elevation of LDH release, and increased the contents of GSH, SOD and T-AOC in supernatant. CONCLUSION CP can protect rat cerebral cortical and hippocampal slices against injury induced by H₂O₂, which may relate to strengthening the ability of anti-oxidative stress.