Neuroprotective effects of insulin-like growth factor-2 in 6-hydroxydopamine-induced cellular and mouse models of Parkinson’s disease

Skin-derived precursor Schwann cells have been reported to play a protective role in the central nervous system. The neuroprotective effects of skin-derived precursor Schwann cells may be attributable to the release of growth factors that nourish host cells. In this study, we first established a cellular model of Parkinson’s disease using 6-hydroxydopamine. When SH-SY5 Y cells were pretreated with conditioned medium from skin-derived precursor Schwann cells, their activity was greatly increased. The addition of insulin-like growth factor-2 neutralizing antibody markedly attenuated the neuroprotective effects of skin-derived precursor Schwann cells. We also found that insulin-like growth factor-2 levels in the peripheral blood were greatly increased in patients with Parkinson’s disease and in a mouse model of Parkinson’s disease. Next, we pretreated cell models of Parkinson’s disease with insulin-like growth factor-2 and administered insulin-like growth factor-2 intranasally to a mouse model of Parkinson’s disease induced by 6-hydroxydopamine and found that the level of tyrosine hydroxylase, a marker of dopamine neurons, was markedly restored, α-synuclein aggregation decreased, and insulin-like growth factor-2 receptor downregulation was alleviated. Finally, in vitro experiments showed that insulin-like growth factor-2 activated the phosphatidylinositol 3 kinase(PI3 K)/AKT pathway. These findings suggest that the neuroprotective effects of skin-derived precursor Schwann cells on the central nervous system were achieved through insulinlike growth factor-2, and that insulin-like growth factor-2 may play a neuroprotective role through the insulin-like growth factor-2 receptor/PI3 K/AKT pathway. Therefore, insulin-like growth factor-2 may be an useful target for Parkinson’s disease treatment.

基于文献数据库的6-OHDA帕金森病大鼠模型特点分析及在中药研究中的应用

目的分析6-OHDA诱导的大鼠PD模型的品系选择、性别、造模要素、模型评价方法以及在抗PD中药研究中的应用情况,以期为6-OHDA模型在帕金森研究中的应用提供参考。方法查阅近20年来中国知网(CNKI)和PubMed中应用6-OHDA建立PD大鼠模型的相关文献,分析6-OHDA诱导的大鼠PD模型的品系选择、性别体重、造模要素、模型评价方法以及在抗PD中药研究中的应用情况。结果6-OHDA诱导的大鼠PD模型多选用雄性SD或Wistar大鼠,造模时注射部位多为单侧黑质、内侧前脑束或纹状体,多在造模4周后检测阿扑吗啡诱导旋转实验、脑组织形态学、分子生物学、生化指标以判断模型成功率及防治PD药物的有效性。结论本文通过对6-OHDA诱导的大鼠PD模型的品系选择、性别、体重、造模要素、模型评价方法以及在抗PD中药研究中的应用情况进行分析,为PD模型的造模和应用提供参考。

姜黄素调控miR-221改善6-羟基多巴胺诱导的帕金森病细胞模型氧化损伤

目的 研究姜黄素通过调控miR-221对6-羟基多巴胺(6-OHDA)诱导帕金森病(PD)细胞模型氧化损伤的影响。方法 PC12细胞分为正常对照组、PD组、姜黄素组;PD细胞转染后分为PD+miR-NC组和PD+miR-221组,以及PD+anti-miR-NC+姜黄素组和PD+anti-miR-221+姜黄素组。通过流式细胞术检测细胞凋亡;Western blotting检测Caspase-3蛋白表达;比色法分析活性氧(ROS)水平,分光光度计法测定超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量;qRT-PCR检测细胞miR-221表达水平。结果 与正常对照组比较,PD组细胞凋亡率、Caspase-3蛋白表达、ROS水平及MDA含量升高,SOD活性、miR-221水平降低(P<0.05);与PD组比较,姜黄素组细胞凋亡率、Caspase-3蛋白表达、ROS水平及MDA含量降低,SOD活性、miR-221水平升高(P<0.05);与PD+miR-NC组比较,PD+miR-221组凋亡率、Caspase-3蛋白表达、ROS水平及MDA含量降低,SOD活性、miR-221水平升高(P<0.05);与PD+anti-miR-NC+姜黄素组比较,PD+anti-miR-221+姜黄素组凋亡率、Caspase-3表达、ROS水平及MDA含量升高,SOD活性、miR-221水平降低(P<0.05)。结论 姜黄素上调miR-221可减轻6-OHDA诱导的PD细胞模型氧化损伤。

Cell viability and dopamine secretion of 6-hydroxydopamine-treated PC12 cells co-cultured with bone marrow-derived mesenchymal stem cells

In the present study, PC12 cells induced by 6-hydroxydopamine as a model of Parkinson＇s Disease, were used to investigate the protective effects of bone marrow-derived mesenchymal stem cells bone marrow-derived mesenchymal stem cells against 6-hydroxydopamine-induced neurotoxicity and to verify whether the mechanism of action relates to abnormal a-synuclein accumulation in cells Results showed that co-culture with bone marrow-derived mesenchymal stem cells enhanced PC12 cell viability and dopamine secretion in a cell dose-dependent manner. MitoLight staining was used to confirm that PC12 cells co-cultured with bone marrow-derived mesenchymal stem cells demonstrate reduced levels of cell apoptosis. Immunocytochemistry and western blot analysis found the quantity of α-synuclein accumulation was significantly reduced in PC12 cell and bone marrow-derived mesenchymal stem cell co-cultures. These results indicate that bone marrow-derived mesenchymal stem cells can attenuate 6-hydroxydopamine-induced cytotoxicity by reducing abnormal α-synuclein accumulation in PC12 cells.

Ghrelin alleviates 6-hydroxydopamine-induced neurotoxicity in SH-SY5Y cells

Ghrelin is a neuropeptide that has various physiological functions and has been demonstrated to be neuroprotective in a number of neurological disease models.However,the underlying mechanisms of ghrelin in Parkinson’s disease remain largely unexplored.The current study aimed to study the effects of ghrelin in a 6-hydroxydopamine(6-OHDA)-induced Parkinson’s disease model and evaluate the potential underlying mechanisms.In the present study,we treated an SH-SY5 Y cell model with 6-OHDA,and observed that pretreatment with different concentrations of ghrelin(1,10,and 100 nM)for 30 minutes relieved the neurotoxic effects of 6-OHDA,as revealed by Cell Counting Kit-8 and Annexin V/propidium iodide(PI)apoptosis assays.Reverse transcription quantitative polymerase chain reaction and western blot assay results demonstrated that 6-OHDA treatment upregulatedα-synuclein and lincRNA-p21 and downregulated TG-interacting factor 1(TGIF1),which was predicted as a potential transcription regulator of the gene encodingα-synuclein(SNCA).Ghrelin pretreatment was able to reverse the trends caused by 6-OHDA.The Annexin V/PI apoptosis assay results revealed that inhibiting eitherα-synuclein or lincRNA-p21 expression with small interfering RNA(siRNA)relieved 6-OHDA-induced cell apoptosis.Furthermore,inhibiting lincRNA-p21 also partially upregulated TGIF1.By retrieving information from a bioinformatics database and performing both double luciferase and RNA immunoprecipitation assays,we found that lincRNA-p21 and TGIF1 were able to form a double-stranded RNA-binding protein Staufen homolog 1(STAU1)binding site and further activate the STAU1-mediated mRNA decay pathway.In addition,TGIF1 was able to transcriptionally regulateα-synuclein expression by binding to the promoter of SNCA.The Annexin V/PI apoptosis assay results showed that either knockdown of TGIF1 or overexpression of lincRNA-p21 notably abolished the neuroprotective effects of ghrelin against 6-OHDA-induced neurotoxicity.Collectively,these findings suggest that ghrelin exerts neuroprotective effects against 6-OHDA-induced neurotoxicity via the lincRNA-p21/TGIF1/α-synuclein pathway.

Differences in brain pathological changes between rotenone and 6-hydroxydopamine Parkinson＇s disease models

Rotenone and 6-hydroxydopamine are two drugs commonly used to generate Parkinson＇s disease animal models.They not only achieve degenerative changes of dopaminergic neurons in the substantia nigra,but also satisfy the requirements for iron deposition.However,few studies have compared the characteristics of these two models by magnetic resonance imaging.In this study,rat models of Parkinson＇s disease were generated by injection of 3 μg rotenone or 10 μg 6-hydroxydopamine into the right substantia nigra.At 1,2,4,and 6 weeks after injection,coronal whole-brain T2-weighted imaging,transverse whole-brain T2-weighted imaging,and coronal diffusion tensor weighted imaging were conducted to measure fractional anisotropy and T2＊ values at the injury site.The fractional anisotropy value on the right side of the substantia nigra was remarkably lower at 6 weeks than at other time points in the rotenone group.In the 6-hydroxydopamine group,the fractional anisotropy value was decreased,but T2＊ values were increased on the right side of the substantia nigra at 1 week.Our findings confirm that the 6-hydroxydopamine-induced model is suitable for studying dopaminergic neurons over short periods,while the rotenone-induced model may be appropriate for studying the pathological and physiological processes of Parkinson＇s disease over long periods.

Dimethyl sulfide,a metabolite of the marine microorganism,protects SH-SY5Y cells against 6-hydroxydopamine and MPP~＋-induced apoptosis

Dimethyl sulfide(DMS)has been historically recognized as a metabolite of the marine microorganism or a disgusting component for the smell of halitosis patients.In our recent study,DMS has been identified as a cytoprotectant that protects against oxidative-stress induced cell death and aging.We found that at near-physiological concentrations,DMS reduced reactive oxygen species(ROS)in cultured PC12 cells and alleviated oxidative stress.The radical-scavenging capacity of DMS at near-physiological concentration was equivalent to endogenous methionine(Met)-centered antioxidant defense.Methionine sulfoxidereductase A(MsrA),the key antioxidant enzyme in Met-centered defense,bound to DMS and promoted its antioxidant capacity via facilitating the reaction of DMS with ROS through a sulfonium intermediate at residues Cys72,Tyr103,Glu115,followed by the release of dimethyl sulfoxide(DMSO).MTT assay and trypan blue test indicated that supplement of DMS exhibited cytoprotection against 6-hydroxydopamine and MPP+induced cell apoptosis.Furthermore,Msr A knockdown abolished the cytoprotective effect of DMS at near-physiological concentrations.The present study reveals new insight into the potential therapeutic value of DMS in Parkinson disease.

Reduced glutathione alleviates the toxic effect of 6-hydroxydopamine on bone marrow stromal cells

We studied the effect of reduced glutathione on bone marrow stromal cells （BMSCs） treated with 6-hydroxydopamine （6-OHDA）, which shows a toxic effect on dopaminergic neurons. The proliferation of BMSCs treated with 6-OHDA decreased, while that of BMSCs treated with reduced glutathione increased. The proliferation of BMSCs treated with both 6-OHDA and reduced glutathione was significantly higher compared with that treated with 6-OHDA alone. These findings indicate that reduced glutathione alleviates the toxic effect of 6-OHDA on BMSCs.

Protective Effect of Immaturue Bitter Orange(Citrus aurantium L.)Flavonoids Extracts on PC12 Cell Injury Induced by 6-Hydroxydopamine

To study the neuro protective effect of flavonoids extracts from immature bitter orange(Citrus aurantium L.),the PC12 cells treated with 6-hydroxydopamine(6-OHDA)were used as the Parkinson’s disease(PD)model.To determine the optimal dose of 6-OHDA for constructing a PD model,PC12 cells were incubated with different concentrations of 6-OHDA for 24 h.After 24 h incubation,PC12 cells of drug groups were added 6-OHDA and different concentrations of flavonoids extracts were measured cell viability by CCK8 for selecting effective concentration of flavonoids extracts;the ROS level was determined using flow cytometry;the levels of MDA,CAT,SOD and GSH-Px were assayed by Colorimetric kit for oxidative stress investigation.Compared with the model group,PC12 cell viability was significantly enhanced(P<0.05),the levels of ROS and MDA were reduced significantly(P<0.05),and the activities of SOD,CAT and GSH-Px were significantly enhanced(P<0.05)in drug groups.In conclusion,immature bitter orange flavonoids extracts could protect PC12 cells against 6-OHDA-induced oxidative stress.

Aged Garlic Extract Reduces ROS Production and Cell Death Induced by 6-Hydroxydopamine through Activation of the Nrf2-ARE Pathway in SH-SY5Y Cells

Many degenerative or pathological processes, such as aging, cancer and coronary heart disease, are related to reactive oxygen species (ROS) and radical-mediated reactions. We examined the effectiveness of aged garlic extract (AGE), a garlic preparation rich in water-soluble cysteinyl moieties, for protection of cells from ROS produced by 6-hydroxy-dopamine (6-OHDA) using human neuroblastoma SH-SY5Y cells. Concomitant treatment of cells with AGE (2 and 4 mg/ml) showed the dose-dependent protective effect on the cell death induced by 6-OHDA. In addition, the AGE treatment significantly suppressed the increase of ROS generation by 6-OHDA. Furthermore, the protective effect of AGE was accompanied by activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway and the increase of mRNAs of heme oxygenase-1 and NAD(P)H quinone oxidoreductase 1. These two enzymes are important in the cellular antioxidant system. These results indicated that AGE protected cells from ROS damage by not only capturing ROS directly but also activating the cellular antioxidant system by stimulating antioxidant gene expression via the Nrf2-ARE pathway. The present study suggested that AGE may be useful for prevention and treatment of cell damage caused by ROS.

Feasibility of establishing model of Parkinson disease by injecting 6-hydroxydopamine at different parts of the nigrostriatal pathway in the brain of rats

BACKGROUND： Previous researches found that animal models with Parkinson disease （PD） could be established by injecting 6-hydroxydopamine （6-OHDA） into medial forebrain bundle （MFB）, substantia nigra compacta （SNC） and caudate-putamen complex （CPU） of the nigrostriatal pathway. OBJECTIVE ： To compare behavioral, biochemica 6-OHDA injections in the areas of MFB, SNC and DESIGN： Controlled observational study and histological properties of these rats undergoing the CPU respectively. SEI-IING： Department of Neurology, First Affiliated Hospital of Guangxi Medical University MATERIALS： A total of 64 adult female SD rats weighing 180-230 g were provided by the Animal Experimental Center of Guangxi Medical University. 6-OHDA （Sigma Company, USA）; Brain solid positioner （Standard model 51600, Stoelting Co., IL, USA）; rotational monitoring of little animal （type QL-1, USA）; high liquid chromatography （HLC, Waters Company）. METHOOS： The experiment was carried out in the Medical Experimental Center of Guangxi Medical University from February to December 2005. ① According to digital table, 64 SD rats were divided into MFB group, SNC group, CPU group and control group with 16 in each group. On the basis of the brain atlas of Paxinos, rats in the first three groups were injected with 5 μL 6-OHDA into right MFB （0 mm of line of incisor tooth, A/P 4.4 mm, L/R 1.2 mm, ON -7.8 mm）, SNC （line of incisor tooth just equal to horizon, A/P -4.8 mm, L/R 1.6 mm, ON -7.8 mm） and CPU （0 mm of line of incisor tooth, A/P 1.2 mm, L/R 2.7 mm, ON -5.4 mm）, respectively. The rats in control group were injected with 5 μL ascorbic acid solution （2 g/L）. One week after operation, 0.1 g/L apomorphine （Apo, 0.05 mg/kg） was subcutaneously injected into neck and then rotational behavior induced by Apo was recorded once a week for 8 weeks. The PD models were considered successful only when rotational times more than or equal to 7 times per minute. Eight weeks after operation, micro-perfusion was used to obtain micro-perfusate in bilateral CPU and contents of 3,4-dihydroxyphenylacetic acid （3,4-DOPAC） and homovanillic acid （HVA） were also measured. In addition, amount of tyrosine hydroxylase positive cells （TH＊） in SNC was counted with immuno- histochemical staining. MAIN OUTCOME MEASURES ： ① Successful rate of PD models; ② contents of dopamine and its metabolite in MFB, SNC and CPU groups and TH＊ amount. RESULTS： All 64 SD rats were involved in the final analysis. ③ Successful rate and rotational behavior： One week after operation, there were 6 successful models both in SNC and MFB groups; in the 2^nd week, there were 6 both in SNC and MFB groups and 1 in CPU group; in the 3^nd week, there were 1 in MFB group and 3 in CPU group; in the 4^nd week, there were 3 in CPU group. Otherwise, no successful case was found out in the next 3 weeks. Abnormal rotational behavior was not observed in control group. Four weeks after operation, successful rates were 81% （13/16） in MFB group, 75% （12/16） in SNC group and 44% （7/16） in CPU group.② Contents of 3, 4-DOPAC and HVA： Eight weeks after operation, contents in the SNC area of the injured side were lower than those on non-lesion side （P 〈 0.01）.③Changes of TH＋ amount： Eight weeks after operation, TH＋ amount in the SNC area of the lesion side was lower than that on non-lesion side （P 〈 0.01 ）. CONCLUSION： Injecting 6-OHDA into MFB, SNC and CPU can damage dopaminergic cells and establish successful PD models.

改良纹状体内两点注射6-OHDA法制备大鼠帕金森病模型

目的:探讨改良的单侧纹状体两点法双靶点注射神经毒素6-羟多巴胺(6-OHDA)制备帕金森病(PD)大鼠模型,对提高制模成功率的可行性。方法:利用立体定向技术以两点法双靶点注射6-羟多巴胺(6-OHDA)于雄性Sprague-Dawley大鼠右侧纹状体,分别于注射后2周和4周检测两组大鼠行为学变化;免疫组织化学法观察大鼠黑质酪氨酸羟化酶(TH)阳性细胞的数量变化;RT-PCR和Western Blot法分别检测TH mRNA和TH蛋白的表达变化。结果:造模2周后模型成功率为82.9%,4周后模型成功率高达88.6%;与对照组比较,模型大鼠6-OHDA注射侧黑质TH阳性细胞数显著减少(P<0.01);TH mRNA和TH蛋白的表达水平均明显降低(P<0.01)。结论:改良的单侧纹状体两点法双靶点注射6-OHDA制备大鼠帕金森病模型简单、易行,成功率高。

外源性Nurr1基因过表达增强SK-N-SH细胞对神经毒素6-OHDA敏感性的研究

目的 通过比较自身不表达Nurrl基因的人神经母细胞瘤细胞SK—N—SH和过表达外源性Null基因的SK—N—SH／Nurrl细胞对神经毒素6-羟多巴胺（6-OHDA）损伤的敏感程度，探讨Null基因与6一OHDA引起的多巴胺（DA）能神经元特异性损伤的相关性。方法①绘制SK—N—SH细胞及SK—N—SH／Nurrl细胞的生长曲线，比较外源性Null基因过表达对细胞增殖率的影响。②用不同浓度的6-OHDA（5—100μmol·L^-1）分别作用两株细胞1—24h，倒置相差显微镜下观察细胞形态变化，MTT测定法比较两株细胞的存活率。③用75μmol·L^-1的6-OHDA作用12h，经Hoechst33342染色，荧光显微镜观察细胞核形态，比较两株细胞的凋亡情况。结果①生长曲线结果显示，SK—N—SH／Null细胞增殖数目低于SK—N—SH细胞一②MTT结果显示，6-OHDA对两株细胞的存活均有抑制作用，但SK—N—SH／Null细胞存活率下降更为明显。③Hoechst33342染色结果显示，用75μmol·L^-1的6-OHDA作用12h后SK—N—SH细胞核没有出现明显的凋亡形态改变，而部分SK—N—SH／Null细胞的细胞核出现了染色质凝聚、碎裂等凋亡形态改变，比例约为22％-24％。结论外源性Null基因过表达抑制SK—N—SH细胞增殖，增强SK—N—SH细胞对6-OHDA的敏感性并有可能促进6-OHDA诱导的细胞凋亡。Null基因可能作为易感因子参与多巴胺能神经元的特异性损伤。

红景天苷通过Nrf2/HO-1通路减轻6-OHDA诱导的SH-SY5Y细胞损伤

目的:研究红景天苷(salidroside,Sal)对6-羟基多巴胺(6-OHDA)诱导的SH-SY5Y细胞损伤的保护作用及可能机制。方法:4-甲基偶氮唑蓝(MTT)检测SH-SY5Y细胞活性,CM-H2DCFDA染色检测活性氧(ROS);Western Blot检测核因子E2相关因子2(nuclear factor E2-related factor 2,Nrf2)与血红素氧合酶-1(HO-1)的蛋白表达;结果:与对照组比较,6-OHDA(150μmol/L)处理SH-SY5Y 24 h后,细胞存活率降低至44.1%±4.6%(P<0.05),ROS水平增加;红景天苷(25,50μmol/L)预处理24 h后,与6-OHDA组比较,细胞存活率分别增加至68.3%±4.1%(P<0.05)和80.0%±6.2%(P<0.01)同时ROS减少。此外,6-OHDA(150μmol/L)可使细胞内Nrf2与HO-1的蛋白表达减少,红景天苷预处理24 h后,Nrf2与HO-1的蛋白表达依次增加。结论:Sal能减少细胞内ROS的水平,对6-OHDA诱导的SH-SY5Y细胞凋亡具有浓度依赖性的保护作用,其作用机制可能与激活Nrf2/HO-1通路有关。

神经节苷脂对6-OHDA损毁交感神经末梢的对抗作用

单次6-OHDA (15mg/kg.i.p.)注射后24h,可使雌性成年小鼠颌下腺内儿茶酚胺荧光神经末梢几乎完全消失;同时用 HPLC 测得腺体内去甲肾上腺素(NA)和多巴胺(DA)的含量下降至正常值的3—4%以下。随着受损交感神经末梢再生过程,NA 和 DA 水平有缓慢的恢复。在损毁2周时 NA 和 DA 含量分别达到正常水平的50%和28%,且在4周时完全恢复。在注射6-OHDA 的同时,和在损伤后12h 内给动物注射4次神经节苷脂(每次50mg/kg.i.p.)并在其后的一周內每天注射一次,可使颌下腺内 NA 含量维持在正常水平;在损毁后4h 及损毁前4d 开始施用神经节苷脂,也可不同程度地对抗交感神经末梢损伤,但作用强度不如前者。实验结果提示:(1)神经节苷脂通过减弱6-OHDA 及其代谢产物的损伤效应能够保护交感神经末梢膜,它可能还有促损伤末梢再生性长芽的作用;(2)损伤后神经节苷脂处理得越早,其效果越好。

补肾止颤方对6-OHDA诱导的帕金森病模型大鼠神经保护作用的研究

目的探讨补肾止颤方对帕金森病(Parkinsons disease,PD)模型大鼠多巴胺能神经元的保护作用。方法将100只Sprague-Dawley大鼠随机分为5组:正常组、模型组、补肾止颤方低剂量组、中剂量组、高剂量组,补肾止颤方按照不同剂量溶于生理盐水中,每天中午灌胃1次,正常组和模型组予以相同体积的生理盐水灌胃。分别在处理10天和20天后检测各组大鼠的行为学,免疫组织化学法检测脑内多巴胺能神经元标志物酶酪氨酸羟化酶(Tyrosine hydroxylase,TH)和多巴胺递质转运子(Dopamine transmitter transporter,DAT),酶联免疫吸附测定(Enzyme-linked immunosorbent assay,ELISA)检测脑内多巴胺及其代谢产物的变化。结果和模型组比不同剂量的补肾止颤方均能够改善PD大鼠的行为学,提高TH、DAT、3,4二羟基苯乙酸(3,4 dihydroxyphenylacetic acid,DOPAC)、5羟色胺(Serotonin,5-HT)、高香草酸(High vanilla acid,HVA)的表达(P <0.05或P <0.01),同时下调单胺氧化酶B(Monoamine oxidase B,MAO-B)的表达(P <0.01)。结论补肾止颤方能够改善6-羟基多巴胺(6-hydroxydopamine,6-OHDA)损伤早期大鼠的行为学改变,增加帕金森病大鼠多巴胺能神经元的数量,并能维持多巴胺能神经元功能,降低神经损伤,有较好的神经保护作用。

二苯乙烯苷通过抑制ROS减轻6-OHDA诱导的PC12细胞凋亡

目的:探讨2,3,5,4’-四羟基二苯乙烯-2-o-β-D-葡萄糖苷(2,3,5,4’-tetrahydroxystibene-2-o-β-D-gluco-side,TSG)对6-羟基多巴胺(6-hydroxydopamine,6-OHDA)诱导的PC12细胞凋亡的影响及其可能的机制。方法:4-甲基偶氮唑蓝(MTT)检测PC12细胞活性;流式细胞仪(FCM)检测PC12细胞凋亡百分率;活性氧(reactive oxy-gen species,ROS)检测试剂盒测定细胞内ROS水平。结果:与6-OHDA处理组(52.6±1.3)%比较,10,20,50μmol/L TSG预处理后,6-OHDA对PC12细胞的毒性明显减轻,使细胞活力分别上升为(66.6±3.2)%(P<0.01),(73.0±1.6)%(P<0.01),(83.9±1.5)%(P<0.01)。流式细胞仪检测显示正常组,6-OHDA组,TSG(10,20,50μmol/L)预处理组,细胞凋亡百分率分别为2.4%,49.9%,25.6%,14.1%,8.5%。TSG(10,20,50μmol/L)预处理后,对比6-OHDA处理组(261.4±8.4)%,PC12细胞内产生的ROS水平分别降低为(255.6±6.8)%,(229.0±9.1)%(P<0.05),(149.2±9.4)%(P<0.01)。结论:TSG对6-OHDA诱导的PC12细胞凋亡具有保护作用,其机制可能与TSG抑制ROS有关。

依达拉奉对6-OHDA诱导的帕金森病大鼠黑质纹状体MDA、NO含量的影响

目的探讨依达拉奉对6-羟基多巴(6-OHDA)诱导的帕金森病大鼠模型的黑质纹状体系统丙二醛(MDA)、一氧化氮(NO)含量的影响。方法将实验动物分为神经生化学和组织学两组,各组分为:(1)正常对照组(n=6);(2)生理盐水(NS)对照组(n=6);(3)依达拉奉组(n=24),依达拉奉又分为0.3mg/kg 14d组(n=6),1mg/kg 14d组(n=6),3mg/kg 14d组(n=6)及3mg/kg 28d组(n=6)4个亚组。采用6-OHDA立体定位下注入SD大鼠左侧前脑内侧束制备PD模型,观察依达拉奉对PD模型大鼠的行为学改变、黑质纹状体尼氏体和MDA、NO含量的影响。结果依达拉奉呈剂量依赖性减少阿朴吗啡(APO)诱发的6-OHDA大鼠PD模型旋转次数(P<0.01),并能改善大鼠自发行为学变化;依达拉奉(3mg/kg 14d、28d)阻止了6-OHDA导致的大鼠黑质纹状体尼氏体细胞数量的减少(P<0.05);阻止了6-OHDA导致的大鼠黑质纹状体MDA、NO的增加(P<0.05)。结论依达拉奉对6-OHDA诱导的PD动物模型具有神经保护作用,能改善6-OHDA损伤大鼠的早期行为学改变,减少6-OHDA导致的大鼠黑质纹状体MDA、NO的含量增加。

侧脑室注射6-OHDA对寒冷应激诱导的大鼠血浆ACTH含量的改变

目的 观察侧脑室注射 6 OHDA对 4℃寒冷应激诱导的血浆ACTH含量的改变。方法 成年Wistar雄性大鼠 3 0只 ,随机分成 5组 (n =6) ,分别为空白对照组、寒冷应激组、6 羟基多巴胺 (6 OHDA)非应激组、6 OHDA +寒冷应激组、配药液 +寒冷应激组。所有动物处理后立即取静脉血用放射免疫法测定其血浆ACTH含量。结果 4℃寒冷应激 4h后血浆ACTH含量明显升高 ,与正常对照组相比有明显差异 (P <0 .0 1) :6 OHDA侧脑室注射后再寒冷应激 ,血浆ACTH含量不再明显升高。