Correlations of transcranial sonography of substantia nigra characteristics with MRI iron deposition on substantia nigra in patients with Parkinson disease

Objective To explore the correlations of transcranial sonography of substantia nigra(SN-TCS)characteristics with MRI iron deposition on substantia nigra in patients with Parkinson disease(PD).Methods Data of SN-TCS and craniocerebral MRI in 120 PD patients were retrospectively analyzed.The patients were divided into iron deposition positive group(positive group,n=46)and iron deposition negative group(negative group,n=74)according to quantitative susceptibility mapping(QSM)value.Then parameters of SN-TCS and MRI were compared between groups(both P<0.05),and correlation analysis were also performed.Results The proportion of high echo positive,strong echo area and QSM value of substantia nigra,as well as of hyper-substantia nigra area/midbrain area(S/M)in positive group were all higher than those in negative group(all P<0.001).No significant difference of midbrain area was found between groups(P>0.05).Strong echo area of substantia nigra and S/M based on SN-TCS were both low-medium positively correlated with substantia nigra QSM value showed on MRI(r=0.497,0.529,both P<0.001).Conclusion SN-TCS characteristics of PD patients were correlated with MRI iron deposition on substantia nigra,among which strong echo area and S/M were valuable for evaluating iron deposition on substantia nigra.

Protective effects of kidney-tonifying Chinese herbal preparation on substantia nigra neurons in a mouse model of Parkinson's disease

The Chinese herbs Herba Epimedii, Fructus Ligustri Lucidi and Rhizoma Polygonati were injected into Parkinson＇s disease mice established via intraperitoneal injection of 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine hydrochloride. The selective monoamine oxidase B inhibitor selegiline was used as a positive control drug. After successive administration for 4 weeks, Herba Epimedii could downregulate the expression of caspase-3 and increase the brain-derived neurotrophic factor level, as well as increase tyrosine hydroxylase activity in the substantia nigra of Parkinson＇s disease mouse models. Rhizoma Polygonaticould downregulate the expression of caspase-3 and FasL, and increase neural growth factor and brain-derived neurotrophic factor levels. Fructus Ligustn Lucidi could downregulate caspase-3 expression. Rhizoma Polygonati and Fructus Ligustn Lucidi did not produce obvious effects on tyrosine hydroxylase activity. Herba Epimedii and Fructus Ligustri Lucidi yielded similar effects on apoptosis-promoting factors to those elicited by selegiline. Herba Epimedii and Rhizoma Polygonati significantly increased the levels of neurotrophic factors compared with selegiline. Herba Epimedii significantly increased tyrosine hydroxylase activity compared with selegiline. It is indicated that the kidney-tonifying Chinese herbal preparation can downregulate the expression of apoptosis-promoting factors, increase neurotrophic factors levels in the substantia nigra and striatum, as well as increase tyrosine hydroxylase activity in the substantia nigra of Parkinson＇s disease mouse models, thereby exerting a stronger or similar neuroprotective effects compared with selegiline.

Anti-apoptotic effect of Shudipingchan granule in the substantia nigra of rat models of Parkinson＇s disease

Levodopa is the gold-standard treatment for Parkinson＇s disease. However, although it alleviates the clinical symptoms, it cannot delay the progressive apoptosis of dopaminergic neurons or prevent motor complications in the long term. In the present study, we investigated the effect of Shudipingchan granule on neuronal apoptosis in a rat model of Parkinson＇s disease, established by injecting 6-hydroxydopamine into the substantia nigra pars compacta and ventral tegmental area. We then administered levodopa （20 mg/kg intraperitoneally, twice daily） with or without Shudipingchan granule （7.5 mL/kg intragastrically, twice daily）, for 4 weeks. The long-term use of levodopa accel- erated apoptosis of nigral cells and worsened behavioral symptoms by activating the extracellular signal-regulated kinase pathway and downstream apoptotic factors. However, administration of Shudipingchan granule with levodopa reduced expression of phosphorylated extracellular signal-regulated kinase 1/2 and Bax, increased tyrosine hydroxylase and Bcl-2, reduced apoptosis in the substantia nigra, and markedly improved dyskinesia. These findings suggest that Shudipingchan granule suppresses neuronal apoptosis by inhibiting the hyper- phosphorylation of extracellular signal-regulated kinase and downregulating expression of anti-apoptotic genes. Shudipingchan granule, used in combination with levodopa, can effectively reduce the symptoms of Parkinson＇s disease.

Experimental Study of Serum Substantia Nigra Neuron Autoantibody and Its Effect in Parkinson Disease Patients

To investigate the serum substantia nigra neuron autoantibody and its effect in the patients with Parkinson disease (PD), substantia nigra slices and a rat model of injection of serum from PD patients in unilateral side substantia nigra were applied. The results showed that the positive rate of substantia nigra neuron autoantibody in PD patients was significantly higher than in the healthy control group (36.67 % vs 6.67 %, P <0.01), but no significant difference was found between PD group and myasthenia gravis (MG) group (26.67 %, P >0.05). The sera from PD patients positive for substantia nigra neuron autoantibody could decrease the number of the dopaminergic neurons more seriously than those from MG and the healthy once respectively (both P <0.01). The results suggested that the immunological mechanism might partly play a role in the development of PD.

Enriched environment elevates expression of growth associated protein-43 in the substantia nigra of SAMP8 mice

An enriched environment protects dopaminergic neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine（MPTP）-induced neuronal injury, but the underlying mechanism for this is not clear. Growth associated protein-43（GAP-43） is closely associated with neurite outgrowth and axon regeneration during neural development. We speculate that an enriched environment can reduce damage to dopaminergic neurons by affecting the expression of GAP-43. This study is designed to test this hypothesis. Three-month-old female senescence-accelerated mouse prone 8（SAMP8） mice were housed for 3 months in an enriched environment or a standard environment. These mice were then subcutaneously injected in the abdomen with 14 mg/kg MPTP four times at 2-hour intervals. Morris water maze testing demonstrated that learning and memory abilities were better in the enriched environment group than in the standard environment group. Reverse-transcription polymerase chain reaction, immunohistochemistry and western blot assays showed that m RNA and protein levels of GAP-43 in the substantia nigra were higher after MPTP application in the enriched environment group compared with the standard environment group. These findings indicate that an enriched environment can increase GAP-43 expression in SAMP8 mice. The upregulation of GAP-43 may be a mechanism by which an enriched environment protects against MPTP-induced neuronal damage.

Electroacupuncture-regulated neurotrophic factor mRNA expression in the substantia nigra of Parkinson's disease rats

Acupuncture for the treatment of Parkinson＇s disease has a precise clinical outcome. This study investigated the effect of electroacupuncture at Fengfu （GV16） and Taichong （LR3） acupoints in rat models of Parkinson＇s disease induced by subcutaneous injection of rotenone into rat neck and back. Reverse transcription-PCR demonstrated that brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor mRNA expression was significantly increased in the substantia nigra of rat models of Parkinson＇s disease, and that abnormal behavior of rats was significantly improved following electroacupuncture treatment. These results indicated that electroacupuncture treatment upregulated brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor mRNA expression in the substantia nigra of rat models of Parkinson＇s disease. Thus, electroacupuncture may be useful in the treatment of Parkinson＇s disease.

Differential protein expression in substantia nigra induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine in a mouse model of chronic Parkinson’s disease

BACKGROUND： To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson＇s disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine （MPTP）, does not exist. In addition, there are no reports of analysis of differential protein expression. OBJECTIVE： To separate and evaluate MPTP-induced differential protein expression through the use of proteomics in the substantia nigra of a mouse model of chronic Parkinson＇s disease. DESIGN： Randomized controlled animal study. SETTING： Department of Neurology, the First Affiliated Hospital, Chongqing Medical University. MATERIALS： Sixteen 8-10-week old, healthy, male, C57BL mice, weighing 20-25 g, and of clean grade, were provided by the Experimental Animal Center of Chongqing Medical University. The experimental animals were disposed according to ethical criteria. MPTP was provided by Sigma Company, USA; Pdquest 2D image analysis software and gelatum/irradiance image analysis system （ChemiDoc XRS） by Bio-Rad, USA; and Voyager DE-PROMALD1-TOF-MS mass spectroscopy analyzer by AB1 Company, USA. METHODS： This study was performed in Chongqing Neurological Laboratory between November 2006 and July 2007. Mice were randomly divided into model and control groups, with 8 mice in each group. Mice in the model group were received a subcutaneous injection of MPTP （25 mg＆g）, twice a week, for five successive weeks, to establish a chronic Parkinson＇s disease model. Mice in the control group received the same volume of a subcutaneous saline injection at the same time points. Mice were sacrificed by anesthesia to rapidly obtain the midbrain for protein separation of the substantia nigra. MAIN OUTCOME MEASURES： （1） 2-ED handbook （Bio-Rad Company） was referenced for two-dimensional electrophoresis, （2） PDQUEST8,0 analytical electrophoresis pattern was adopted to evaluate differential protein expression. （3） Peptide mass finger print map and data were retrieved on http：//www.prospector.ucsf.edu to compare differential substantia nigral protein expression in the two groups. RESULTS： Two-dimensional gel electrophoresis of substantia nigra tissue indicated that there were 33 differential protein expressions between the two groups. Three new proteins were evaluated, including α -enolase, which exhibited regulated expression, tumor necrosis factor ligand superfamily member 4, and cyclin-dependent kinase inhibitor 1B. CONCLUSION： There are three proteins that exhibit differential expression in the substantia nigra- α -enolase, tumor necrosis factor ligand superfamily member 4, and cyclin-dependent kinase inhibitor 1B.

Mechanisms of secondary damage to the thalamic nucleus and substantia nigra in an adult hypertensive rat model following middle cerebral artery occlusion

BACKGROUND： Following ischemia, apoptosis is observed at the ipsilateral ventropostenor thalamic nucleus and substantia nigra, which are distant from, but connected to, the ischemic cerebral cortex, in animals with normotension. However, secondary brain damage in hypertension has not been clearly investigated. OBJECTIVE： The present study determined whether neuronal apoptosis is associated with neuronal loss in the ipsilateral ventroposterior thalamic nucleus and substantia nigra following cortical ischemia in adult hypertensive rats. Results should provide options for determining a time window for anti-apoptotic therapy. DESIGN, TIME AND SETTING： All experimental procedures in this randomized, controlled trial were conducted at the Neurological Laboratory of the First Affiliated Hospital of Sun Yat-sen University of China between October 2006 and July 2008. MATERIALS： Monoclonal primary antibodies specific to mouse anti-rat microtubule-associated protein 2 and glial fibrillary acidic protein were respectively purchased from Sigma Chemical, USA and BD Pharmingen, USA. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling （TUNEL） detection kits were purchased from Roche Applied Science, Switzerland and Upstate, USA, respectively. METHODS： A total of 64 male, Sprague Dawiey rats, aged 60-90 days, were equally and randomly divided into middle cerebral artery occlusion and sham surgery groups. Renovascular hypertension was established in both groups by renal artery occlusion. Right distal middle cerebral artery occlusion was performed by electrocoagulation in the middle cerebral artery occlusion group. MAIN OUTCOME MEASURES： Microtubule-associated protein 2 and glial fibrillary acidic protein were detected by immunohistochemistry, and apoptotic cells were observed by TUNEL assay. The stainings were separately detected in the ipsilateral ventroposterior thalamic nucleus and substantia nigra. RESULTS： During the 4 weeks following distal middle cerebral artery occlusion in renovascular hypertensive rats, microtubule-associated protein 2 expression gradually, but significantly, decreased （P 〈 0.05）. Expression of glial fibrillary acidic protein increased significantly in the ipsilateral ventroposterior thalamic nucleus and substantia nigra （P 〈 0.05） and reached a peak at 4 weeks. In addition, number of apoptotic cells was significantly increased in both areas compared with the sham controls （P 〈 0.05）, with a peak at 2 weeks. CONCLUSION： Results suggested that neuronal loss in the ipsilateral ventroposterior thalamic nucleus and substantia nigra following distal middle cerebral artery occlusion in hypertensive rats could be a secondary event resulting from apoptosis. The temporal apoptosis profile provides options for determining a time window for anti-apoptotic therapy at 2 weeks after stroke.

Effects of Zhichan powder on signal transduction and apoptosis-associated gene expression in the substantia nigra of Parkinson's disease rats

Previous studies have shown that Zhichan powder elevated immunity and suppressed oxidation in mice. Rat models of Parkinson＇s disease were induced by stereotaxically injecting 6-hydroxydopamine into the substantia nigra. The rat models were intragastrically treated with Zhichan powder, which is composed of milkvetch root, ginseng, bunge swallowwort root, himalayan teasel root. Magnolia officinalis, Ligustrum lucidum Ait. and szechwan Iovage rhizome. Immunohistochemistry and reverse transcription-PCR results demonstrated that mRNA and protein expression of tumor necrosis factor receptor 1, Fas, caspase-8, cvtochrome C, Bax, casDase-3, and p53 significantly increased, but Bcl-2 expression significantly decreased in the substantia nigra of rats with Parkinson＇s disease. Following Zhichan powder administration, mRNA and protein expression of tumor necrosis factor receptor 1, Fas, caspase-8, cytochrome C, Bax, caspase-3, and p53 diminished, but Bcl-2 expression increased in the rat substantia nigra. These results indicate that Zhichan powder regulates signal transduction protein expression, inhibits apoptosis, and exerts therapeutic effects on Parkinson＇s disease.

Expression of calbindin D28K in substantia nigra of model rats with Parkinson disease

BACKGROUND： Previous researches suggested that expression level of calbindin D28K mRNA decreased in substantia nigra （SN） of model rats with Parkinson disease （PD）, and this might be related to the decrease of anti-degeneration potentials of dopaminergic neurons. OBJECTIVE： To observe expression changes of calbindin D28K in SN dopaminergic neurons during their degeneration and death in midbrain of PD model rats. DESIGN： Completely randomized grouping design SETTING： Department of Neurobiology, Xuzhou Medical College MATERIALS＂ A total of 92 healthy male SD rats, with the age of 3 months, weighing 200-250 g, were selected from Experimental Animal Center of Xuzhou Medical College [certification： SCXK （su） 2003-0003]. Calbindin D28K（CB）, tyroxine hydroxylase （TH）, ABC kit, 6-hydroxydopamine （6-OHDA） and Nissl dyes were provided by Sigma Company, and sheep serum was provided by Beijing Zhongshan Company. METHODS： The experiment was carried out in the Neurobiological Center of Xuzhou Medical College from October 2003 to October 2004. ① With lot method, rats were divided into blank control group （n=28）, experimental control group （n=-28） and experimental group （n=36）. Rats in experimental group were injected with 6-OHDA at right corpus striatum for PD modeling; rats in experimental control group were injected with saline at the same site; rats in blank control group did not give any injections.② On the 7^th, 14^th, 21^st and 28^th days, SN segments on right midbrain from every 5 rats in experimental group were fixed, embedded with paraffin and cut into successively coronary pieces. Rats in other two groups were treated with the same methods and then stained with Nissl to show neuronal form. Meanwhile, CB and TH antibodies staining with immunohistochemistry were used to show CB containing dopaminergic neurons and dopaminergic neurons, and cells were calculated and observed under optic microscope. ③ On the 14^th and 28^th days, every 4 rats in experimental group and every 4 rats in control group were selected to obtain their brains and separate SN on the injured side. Western blot was used to detect expression of calbindin D28K, protein band was scanned with imaging equipment, and data were analyzed with LabWorks software. MAIN OUTCOME MEASURES：① On the 7^th, 14^th, 21^st and 28^th days, Nissl staining results of SN neurons and immunohistochemical staining results of CB and TH antibodies; ② On the 14^th and 28^th days, Western blot results of calbindin D28K in SN neurons, RESULTS; Among 92 rats, 2 rats in experimental group died after 1 day due to 6-OHDA injection and other 90 rats were involved in the final analysis. ①Nissl staining results： On the 7^th day of 6-OHDA injection, most neuronal somas on right SN pars compacta were shown as deep pycnosis or lysis breakage; on the 14^th and 21^st days, amount of neurons was decreased remarkably; on the 28^th day, most neurons in SN pars compacta disappeared. ② Results of immunohistochemical staining： Amount of positive neurons of calbindin D28K in right SN pars compacta was not changed on the 7^th day after 6-OHDA injection; on the 14^th day, the amount was higher in experimental group than that in both control groups （P 〈 0.01） and was decreased till the 21^st day, but it was still higher than that in the two control groups （P 〈 0.05）; on the 28^th day, positive neurons of calbindin D28K nearly disappeared, and the amount was lower than that in the two control groups （P 〈 0.01）. In addition, on the 7^th day after 6-OHDA injection into corpus striatum, positive TH neurons decreased 24% in right SN, and there was significant difference from that in control groups; on the 14^th, 21^st and 28^th days, positive TH neurons decreased 37%, 46% and 64%, respectively. ③ Western blot results： On the 14＇h day after 6-OHDA injection into corpus striatum, expression of calbindin D28K in right SN was higher in experimental group than that in both control groups （P 〈 0.05）; however, on the 28^th day, the expression was lower than that in the two control groups （P 〈 0.01 ）. CONCLUSION ： During degeneration and death of dopaminergic neurons, CB expression in SN pars compacta increases firstly and decreased gradually.

N-cadherin expression in the midbrain substantia nigra of perinatal rats

BACKGROUND： Cellular adhesion molecule mediates the effects of glial cell line-derived neurotrophic factor in dopaminergic neurons during nervous system development. It is assumed that cellular adhesion molecule plays an important role in dopaminergic neuron development. OBJECTIVE： To investigate N-cadherin expression in the midbrain substantia nigra during rat development. DESIGN, TIME AND SETTING： The developmental biology, controlled study was performed at the Laboratory of Research Center of Neurobiology, Xuzhou Medical College, China from April to October 2007. MATERIALS： Sprague Dawley rats （embryonic days 16, 18, and 20, as well as postnatal days 1, 3, 7, 14, and 21） were selected for this study. N-cadherin antibody was purchased from Santa Cruz, USA. METHODS： N-cadherin expression in the midbrain substantia nigra of perinatal rats was detected using reverse transcription polymerase chain reaction, Western blot, and immunohistochemistry methods. N-cadherin-positive cells were counted. MAIN OUTCOME MEASURES： N-cadherin mRNA, protein, and positive cells in the rat midbrain substantia nigra were quantified. RESULTS： The results of reverse transcription polymerase chain reaction and Western blot demonstrated that altered N-cadherin mRNA levels were similar to protein levels in the midbrain substantia nigra. N-cadherin mRNA and protein expression was low in the midbrain substantia nigra of embryonic day 16 rats but gradually increased, and reached a peak at postnatal day 1. N-cadherin mRNA and protein levels were still high at postnatal days 3 and 7, but significantly decreased at postnatal day 14. There was no significant difference in N-cadherin mRNA and protein expression between postnatal days 14 and 21 （P 〉 0.05）. The immunohistochemistry results demonstrated that there was no significant difference in the quantity of N-cadherin-positive cells per area in rats from embryonic day 16 to postnatal day 7 （P 〉 0.05）. The quantity of N-cadherin-positive cells per area was significantly decreased in rats at postnatal day 14. There was no significant difference in the number of N-cadherin-positive cells per area between postnatal days 14 and 21 （P 〉 0.05）. CONCLUSION： N-cadherin expression was reduced during embryonic stages, but reached a peak at postnatal days 1-7, and then gradually decreased in the rat midbrain substantia nigra.

Directional induction of dopaminergic neurons from neural stem cells using substantia nigra homogenates and basic fibroblast growth factor

To date, complex components of available reagents have been used for directional induction of neural stem cells into dopaminergic neurons, resulting in a poor ability to repeat experiments. This study sought to investigate whether a homogenate of the substantia nigra of adult rats and/or basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons. Tyrosine hydroxylase-positive cells were observed exclusively after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor for 48 hours in vitro. However, in the groups treated with homogenate supernatant or basic fibroblast growth factor alone, tyrosine hydroxylase expression was not observed. Moreover, the content of dopamine in the culture medium of subventricular zone neurons was significantly increased at 48 hours after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor. Experimental findings indicate that the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons in the substantia nigra with the ability to secrete dopamine.

Intracerebroventricularly-administered 1-methyl-4-phenylpyridinium ion and brain-derived neurotrophic factor affect catecholaminergic nerve terminals and neurogenesis in the hippocampus,striatum and substantia nigra

Parkinson＇s disease is a progressive neurological disease characterized by the degeneration of dopaminergic neurons in the substantia nigra.A highly similar pattern of neurodegeneration can be induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine（MPTP） or 1-methyl-4-phenylpyridinium ion（MPP＋）,which cause the death of dopaminergic neurons.Administration of MPTP or MPP＋ results in Parkinson＇s disease-like symptoms in rodents.However,it remains unclear whether intracerebroventricular MPP＋ administration affects neurogenesis in the substantia nigra and subgranular zone or whether brain-derived neurotrophic factor alters the effects of MPP＋.In this study,MPP＋（100 nmol） was intracerebroventricularly injected into mice to model Parkinson＇s disease.At 7 days after administration,the number of bromodeoxyuridine（Brd U）-positive cells in the subgranular zone of the hippocampal dentate gyrus increased,indicating enhanced neurogenesis.In contrast,a reduction in Brd U-positive cells was detected in the substantia nigra.Administration of brain-derived neurotrophic factor（100 ng） 1 day after MPP＋ administration attenuated the effect of MPP＋ in the subgranular zone and the substantia nigra.These findings reveal the complex interaction between neurotrophic factors and neurotoxins in the Parkinsonian model that result in distinct effects on the catecholaminergic system and on neurogenesis in different brain regions.

骨化三醇、益生菌对帕金森病小鼠模型肠道迷走神经、黑质a-syn的影响

目的以益生菌为对照组,分析骨化三醇对帕金森病(PD)小鼠模型黑质、结肠迷走神经α突触核蛋白的影响。方法选取雄性SPF级健康C57BL/6小鼠45只,随机分为A组(正常对照,n=5)、B1组(PD模型对照,n=10)、B2组(PD模型益生菌干预,n=10)、B3组(PD模型骨化三醇干预,n=10),B4组(PD模型益生菌联合骨化三醇干预,n=10)。每组均连续喂养3个月。喂养结束完成行为学、相关血液学检测后处死实验小鼠取各组n=3,分别取大脑黑质和结肠迷走神经组织,行Western blot检测a-突触核蛋白(a-syn)含量。结果结肠迷走神经中a-syn含量显示:(1)PD模型组(B1组)、益生菌干预组(B2组)、骨化三醇干预组(B3组)明显高于正常组(A组),^(a)P<0.01;(2)益生菌干预组(B2组)、骨化三醇干预组(B3组)、益生菌+骨化三醇联合干预组(B4组)均低于PD模型组(B1组),^(b)P<0.01;(3)骨化三醇干预组(B3组)高于益生菌干预组(B2组),^(c)P<0.01;(4)益生菌+骨化三醇联合干预组(B4组)低于骨化三醇干预组(B3组),^(d)P<0.01;黑质中的a-syn含量显示:(1)PD模型组(B1组)、益生菌干预组(B2组)明显高于正常组(A组),^(a)P<0.01;(2)益生菌干预组(B2组)、骨化三醇干预组(B3组)、益生菌+骨化三醇联合干预(B4组)均低于PD模型组(B1组),^(b)P<0.01;(3)骨化三醇干预组(B3组)、益生菌+骨化三醇联合干预(B4组)均低于益生菌干预组(B2组),^(d)P<0.01。结论(1)益生菌、骨化三醇对于PD小鼠肠道迷走神经中的a-syn的沉积均有抑制作用,而益生菌在此过程中显示更显著的作用;(2)益生菌、骨化三醇可不同程度减少PD小鼠黑质中的a-syn的沉积,其中骨化三醇对于α-syn中枢沉积的干预作用尤显著。

帕金森病患者血铜蓝白水平与黑质铁沉积相关性分析

目的:探讨帕金森病(PD)患者血铜蓝蛋白水平与黑质铁沉积的相关性。方法:回顾性分析收治的107例PD患者临床资料,所有患者均检测血浆铜蓝蛋白(Cp)水平,据其水平分成对照组(Cp≥0.25 g/L)52例与观察组(Cp<0.25 g/L)45例。运用PD统一评分量表第三部分(UPDRS-Ⅲ)、Hoehn Yahr(H-Y)分级评估患者疾病状况,所有患者均接受经磁敏感加权成像检查,观察两组不同脑区相位值变化,并分析Cp水平与H-Y分级及Cp水平与UPDRS-Ⅲ评分、相位值的相关性。结果:观察组SN相位值低于对照组,UPDRS-Ⅲ评分及Cp低于对照组,差异有统计学意义(均P<0.05);中晚期H-Y分级患者UPDRS-Ⅲ评分低于对照组,差异有统计学意义(P<0.05)。Spearmna相关性分析,SN相位值与Cp水平、UPDRS-Ⅲ评分均呈正相关(均P<0.05),而Cp、SN相位值与H-Y分级不具有相关性(均P>0.05)。结论:PD患者Cp水平与黑质铁沉积密切相关,PD患者血浆Cp越低,黑质铁沉积越严重。

Ghrelin基因敲除对小鼠黑质区多巴胺能神经元突触后电位的影响

目的探讨胃饥饿素(ghrelin)基因敲除对小鼠黑质多巴胺能神经元突触后电位的影响。方法分别选取10周龄雄性ghrelin基因敲除小鼠(ghrelin^(-/-)组)及其同窝雄性野生型(WT)小鼠(WT组)的黑质组织,采用转录组学测序(RNA-seq)技术筛选差异表达基因(DEGs),通过KEGG通路富集分析DEGs可能参与的神经元突触活动相关信号通路,采用实时荧光定量PCR(RT-qPCR)方法对筛选出的DEGs进行验证,并应用蛋白免疫印迹(Western blotting)方法检测神经元突触活动相关基因的蛋白表达情况。结果与WT组相比,ghrelin^(-/-)组小鼠多巴胺能神经元突触传递信号通路上的23个基因水平发生了显著性变化,其中谷氨酸促离子型受体α-氨基-3-羟基-5-甲基-4-异唑丙酸型亚基3(GluA3)和糖原合酶激酶-3β(GSK-3β)分别调控神经元突触后膜上的α-氨基-3-羟基-5-甲基-4-异唑丙酸受体和N-甲基-D-天冬氨酸受体;在ghrelin^(-/-)组小鼠黑质组织中,GluA 3和GSK-3β基因表达出现明显的下调。RT-qPCR方法检测结果显示,与WT组相比,ghrelin^(-/-)组小鼠黑质组织当中GluA 3和GSK-3βmRNA水平明显下调(t=2.408、2.740,P<0.05)。Western blotting方法检测结果显示,与WT组相比,ghrelin^(-/-)组小鼠黑质组织中GluA3蛋白的表达水平明显上调(t=2.530,P<0.05),GSK-3β蛋白的表达明显下调(t=3.469,P<0.05)。结论Ghrelin基因敲除可能通过使小鼠黑质多巴胺能神经元突触后电位长时程增强,从而增强兴奋性突触传递活动,参与运动调控。

天智颗粒对帕金森病小鼠模型黑质和脊髓多巴胺能神经元的影响

目的 探讨天智颗粒对帕金森病(PD)小鼠模型脑黑质和脊髓多巴胺(DA)能神经元的影响。方法 2022年9月采用1-甲基-4-苯基-1,2,3,6-四氢吡啶25 mg/(kg·d)腹腔注射5 d的方法构建PD小鼠模型,采用随机数字表法分为模型组和天智颗粒5、2、1 g/kg组,每组10只,另取10只小鼠作为正常对照组。灌胃给药2周后比较各组小鼠行为学变化、中脑黑质和脊髓DA能神经元存活数量及形态变化、神经元内酪氨酸羟化酶阳性表达情况等。结果 与正常对照组比较,模型组小鼠悬挂能力下降、游泳时间缩短,经天智颗粒干预后可有效提高小鼠悬挂能力,延长游泳时间,黑质和脊髓灰质前角DA能神经元数量和神经元内酪氨酸羟化酶阳性表达均明显减少,经天智颗粒5、2 g/kg干预后小鼠黑质和脊髓DA能神经元检测指标明显改善,差异均有统计学意义(P<0.05)。结论 天智颗粒可改善PD小鼠行为学,提高中脑黑质和脊髓部位DA能神经元及突起的存活数目,增加中枢神经系统内DA的含量,表明天智颗粒对黑质和脊髓灰质前角多巴能神经元具有保护作用。

神经黑色素敏感磁共振成像在帕金森病中的应用进展

神经黑色素敏感MRI(neuromelanin-sensitive MRI,NM-MRI)是一种无创可视化脑内神经黑色素(neuromelanin,NM)含量变化的新兴技术,对颅内NM的变化具有敏感性。帕金森病(Parkinson’s disease,PD)是常见的神经退行性疾病,病理表现为黑质中含NM的多巴胺神经元损失,NM减少。NM-MRI能够检测到颅内NM含量变化,间接提示多巴胺神经元活性状态。NM-MRI在PD诊断中的作用不可忽视,因此,本文就近年来NM-MRI在PD诊断中的研究进展进行综述,为后续相关研究提供参考资料,期待随着NM-MRI技术的成熟,早日成为辅助临床PD诊断的影像学工具,同时对PD病理机制研究作出贡献。

黄芪提取物对帕金森病小鼠黑质区白介素-17通路的影响

目的:探究黄芪提取物干预白介素-17(IL-17)信号通路治疗帕金森病(PD)作用机制。方法:将30只雄性C57BL/6小鼠均分为五组。除对照组之外均采用MPTP诱导PD模型,建模成功后,低、中、高浓度黄芪组分别以50、100、200 mg/kg黄芪提取物持续灌胃14 d,模型组和对照组采用等量0.9%氯化钠溶液灌胃。灌胃后结束后采用转棍实验和爬杆实验评估各组小鼠行为表现。免疫组化法测定各组脑黑质致密区(SNpc)酪氨酸羟化酶(TH)和Th17细胞数目;Western blot测定纹状体区IL-17、抗肿瘤坏死因子受体相关因子6(TRAF6)、核因子-κB(NF-κB)、白介素-1β(IL-1β)、白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、环氧合酶-2(COX-2)蛋白相对表达量。结果:与对照组比较,模型组和各浓度黄芪组小鼠转棍掉落潜伏期明显缩短,爬杆实验头向下时间(T1)、由杆顶爬至杆底所用时间(T-LA)明显延长,SNpc区TH表达水平下降,Th17细胞数目增多,纹状体区IL-17、TRAF-6、NF-κB、IL-1β、IL-6、TNF-α、COX-2蛋白相对表达水平明显升高(均P<0.05)。与模型组比较,各浓度黄芪组小鼠转棍掉落潜伏期明显延长,爬杆实验T1和T-LA明显缩短,SNpc区TH表达水平升高,Th17细胞数目减少,纹状体区IL-17、TRAF-6、NF-κB、IL-1β、IL-6、TNF-α、COX-2蛋白相对表达水平明显下降(均P<0.05),且与黄芪提取物浓度呈正相关。结论:黄芪提取物能有效改善PD模型小鼠转棍和爬杆活动能力,保护SNpc区TH阳性神经元,其机制可能与抑制IL-17/TRAF-6/NF-κB信号通路,减少多巴胺神经元炎症性损伤凋亡有关。

基于体素形态学分析探讨脑梗死远隔丘脑和黑质损害研究

目的探讨颅脑核磁共振成像(magnetic resonance imaging,MRI)体素形态学分析(voxel-based mor⁃phometry,VBM)对检测脑梗死患者远隔丘脑和黑质继发性损害的临床价值。方法前瞻性招募19例首次单侧大脑中动脉(middle cerebral artery,MCA)供血区脑梗死患者,在发病后1周、1个月、3个月分别行MRI三维全脑扫描,应用VBM方法分析丘脑和黑质体积的变化。结果VBM结果显示,与发病1周时相比,脑梗死患者在发病1个月和3个月时同侧丘脑体积减小(体素值分别缩小637 mm^(3)、1488 mm^(3),P<0.01),且体积萎缩部位主要位于丘脑背内侧核。同样,与发病1周时相比,脑梗死患者在发病1个月和3个月时同侧黑质体积减小(体素值分别缩小64 mm^(3)、76 mm^(3),P<0.05)。结论VBM技术可在脑梗死后1~3个月检测MCA供血区脑梗死患者同侧丘脑和黑质体积缩小,可用于检测其继发性损害。