贯叶金丝桃提取物对慢性不可预知性温和应激致小鼠抑郁的改善作用

Effect of Hypericum Perforatum L Extracts on depression induced by chronic unpredictable mild stress in mice

目的 观察贯叶金丝桃提取物对慢性不可预知性温和应激法致小鼠抑郁的改善作用.方法 采用慢性不可预知性温和应激法建立抑郁小鼠模型,将造模成功的50只小鼠按照随机数字表法随机分为模型对照组、盐酸氟西汀组( 2. 6 mg/kg)、贯叶金丝桃提取物低、中、高( 0. 2 g/kg、0. 4 g/kg、0. 8 g/kg) 剂量组,每组10只.另取10只体质量相匹配的正常小鼠作为正常对照组.正常对照组、模型对照组每天灌胃给予纯水,其余各组分别灌胃给予相应药液,连续4周.除正常对照组外,其余各组小鼠在灌胃给药期间继续进行慢性不可预知性温和应激,末次给药后小鼠进行糖水偏爱、强迫游泳检测.眼眶后静脉丛采血分离血清,Elisa法检测多巴胺( dopamine,DA)、脑源性神经营养因子(brain derived neurotrophic factor,BDNF)水平,HE染色对小鼠海马组织做病理学检查. 结果与正常对照组比较,模型对照组小鼠第1、第2、第3、第4周的体质量均显著降低( t=2. 739,4. 162, 4. 082,3. 957;均P<0. 05);第1、2、3、4周,贯叶金丝桃提取物低、中、高剂量组小鼠体质量与模型对照组比较均差异无统计学意义(均P>0. 05).与正常对照组比较,模型对照组小鼠糖水偏爱指数显著降低[(61. 3±4. 5) %, ( 52. 6± 5. 2) %;t=2. 721,P<0. 05],游泳不动时间延长[( 44. 3 ± 20. 0) s, (101. 8±50. 8)s;t=2. 939,P<0. 05],均差异有统计学意义;与模型对照组比较,贯叶金丝桃提取物低、中、高剂量组小鼠糖水偏爱指数均升高[(61. 8±4. 7)%,(65. 2±4. 1)%,( 62. 6± 5. 6)%;t=-3. 005, 5. 073,-2. 928;均P<0. 05],游泳不动时间缩短[(47. 2±17. 9)s,(54. 8±50. 3)s,(61. 3±44. 2)s;t=2. 803,1. 921,1. 903,均 P<0. 05]. Elisa结果显示,相对于正常对照组,模型对照组小鼠血清 DA、BDNF水平明显降低(t=3. 031,8. 507,均P<0. 05);与模型对照组比较,贯叶金丝桃低、高剂量组小鼠血清DA明显升高(t=5. 025,3. 414,P<0. 05),贯叶金丝桃高剂量组BDNF亦明显升高( t=6. 098,P<0. 05),差异有统计学意义. HE染色显示,与正常对照组小鼠相比,模型对照组小鼠海马CA3区神经元损害严重,提示小鼠模型成立.与模型对照组比较,三个剂量组海马CA3区细胞萎缩、变性均明显减轻,贯叶金丝桃提取物低、中、高剂量组小鼠海马CA3区神经元萎缩、变形有所缓解.结论 贯叶金丝桃提取物对抑郁模型小鼠的抑郁行为有明显的改善作用,其作用可能是通过提高DA、BDNF的水平,减轻海马CA3区神经元损伤有关.

Objective To observe the improving effect of Hypericum Perforatum L Extracts (HPLES)on depression induced by chronic unpredictable mild stress in mice. Methods The depression model was established by the method of chronic unpredictable mild stress. Fifty depression model mice were divided into model control group,fluoxetine hydrochloride group (2. 6 mg / kg),Hypericum perforatum ex-tract low,medium and high (0. 2 g / kg,0. 4 g / kg,0. 8 g / kg) dose groups according to the random num-ber table method. Another 10 normal mice matched with body weight were taken as the normal control group. The mice in normal control group and the model control group were given pure water by gavage every day,and the mice in other groups were given corresponding solution by gavage for 4 weeks. In addition to the normal control group,the mice in other groups continued to undergo chronic unpredictable mild stress during gavage. The sugar water preference test and forced swimming test were performed after the last administration. Blood samples were collected from the posterior orbital venous plexus,and the levels of dopamine (DA) and brain-derived neurotrophic factor (BDNF) were measured by Elisa. The hippocampal tissues of mice were exam-ined by HE staining. Results Compared with the normal control group,the body mass of mice in the model control group decreased significantly at the first,second,third and fourth weeks ( t=2. 739,4. 162,4. 082, 3. 957;all P<0. 05). At the first,second,third and fourth weeks,the body mass of mice in the low,middle and high dose group of Hypericum perforatum extract were not significantly different from those in the model control group (all P>0. 05). Compared with the normal control group,the sugar water preference index of mice in the model control group was significantly reduced((61. 3± 4. 5)%,(52. 6± 5. 2)%;t=2. 721,P<0. 05),the swimming immobility time was prolonged(( 44. 3± 20. 00) s,(101. 8± 50. 8) s;t=2. 939,P<0. 05),the difference were statistically significant. Compared with the model control group,the sugar water preference index of mice in the low,middle and high dose group of Hypericum perforatum extract increased ((61. 8±4. 7)%,(65. 2±4. 1)%,(62. 6±5. 6)%,t=-3. 005,5. 073,-2. 928,all P<0. 05),the swimming immobility time decreased ((47. 2±17. 9) s,(54. 8±50. 3) s,(61. 3±44. 2) s;t=2. 803,1. 921,1. 903,all P<0. 05). The results of Elisa showed that compared with the normal control group,the levels of serum DA and BDNF of mice in the model control group were significantly lower (t=3. 031,8. 507,all P<0. 05);com-pared with the model control group,the levels of serum DA of mice in the low dose and high dose group of Hypericum perforatum were significantly higher (t=5. 025,3. 414,P<0. 05),and the serum BDNF of mice in the high dose group of Hypericum perforatum was also significantly higher (t=6. 098,P<0. 05),the differ-ence was statistically significant. HE staining showed that compared with the normal control group,the neu-rons in CA3 area of hippocampus in the model control group mice were seriously damaged,suggesting the es-tablishment of the mouse model. Compared with the model control group,the atrophy and degeneration of hippocampal CA3 cells in the three dose groups were significantly reduced. The atrophy and deformation of hippocampal CA3 neurons in the low,middle and high dose groups of Hypericum perforatum extract were re-lieved. Conclusion HPLES have obvious improving and antidepressant effects on the depression model mice induced by chronic unpredictable stress. The above effects may be related to the improvement of serum DA,DBNF level and reduce neuronal damage in CA3 area.