2026-11-092026-11-09https://scholars.csmu.edu.tw/handle/123456789/38403Dementia is diagnosed, in about 40% of patients with Parkinson’s disease (PD), several years after the onset of PD. Inflammation in the dopaminergic system is found in the PD. It has been found that the levels of interleukin-1 (IL-1), IL-2, IL-6, and tumor necrosis factor (TNF-􀍉) in the striatum and cerebrospinal fluid are increased in the PD patients. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is used to induce the PD animal model; it can cause the dopaminergic degeneration and the elevation of proinflammatory cytokines. However, the MPTP-induced enhancement of cytokines cannot be recovered by the treatment of L-DOPA, indicating that another mechanisms are involved. On the other hand, the role of anti-inflammatory cytokines, IL-6 and IL-10, in the dopaminergic degeneration is not yet clear. It has been reported that chronic injection of certain kinds of cytokines can cause the hippocampal degeneration in aged animals and the impairment of special learning. Furthermore, microglia release proinflammatory cytokines when the damage of dopaminergic neuron occurred. It suggest that inflammatory cytokines may cause neuronal degenerations in the cortex, hippocampus, and limbic system, which may result in chronic inflammation and may also mediate emotional and cognitive dysfunctions in PD. The glutamatergic system in the hippocampus, temporal cortex, medial prefrontal cortex, and parietal cortex is involved in the function of learning and memory. The dopaminergic degeneration results in the hyperactivation of glutamatergic system. Glutamate, through the NMDA receptor, takes part in the excitotoxic neuronal apoptosis in the inflammation caused by the cytokines. In addition, amantadine, an agonist of NMDA receptor, has been reported to be able to inhibit the glutamatergic activity and prevent the substantia nigra from neurodegeneration caused by MPTP. This drug has been clinically used to treat the motor dysfunction in PD and Alzheimer’s disease for decades. Thus, these data suggest that the inflammatory cytokines induced by the dopaminergic degeneration may, through the glutamatergic NMDA receptor, cause a wide neuronal damage and result in the dementia. The following experiments are proposed to be taken in 2 years: (1) To establish the PD animal model by using the MPTP; to analyze the emotional behavior and cognitive function by using the elevated plus-maze and the object exploration test in an open field, respectively; and to detect the changes of IL-1, IL-2, IL-6, TNF-􀍉, IL-4, and IL-10 in the hippocampus, temporal cortex, medial prefrontal cortex, parietal cortex, and striatum by using the enzyme-linked immunosorbent assay. The relationship between the cytokines and the behavior will be also evaluated. (2) To elucidate the role of glutamatergic system in the changes of immune, and behavioral functions in the MPTP-induced PD model by using the pharmacological manipulation of NMDA receptor through the injection of amantadine before and after the MPTP lesion. (3) Immunohistochemistry will be taken to detect the tyrosine hydroxylase in the substantia nigra and the striatum and to evaluate the activation of microglia. The results from this study will provide the evidence to clarify the role of glutamatergic and immunological system as well as the microglia in the pathophysiological mechanisms of PD and its emotional and cognitive dysfunction.巴金森氏症的病理過程涉及多巴胺神經系統發炎及退化現象，約40%巴金森氏症患者 在發病數年後會合併出現失智症。此疾病患者的紋狀體及腦脊髓液内「發炎性細胞激素」 (proinflammatory cytokines ) interleukin-1 (IL-1) IL-2、IL-6 及 tumor necrosis factor ( TNF-a )含量增加。研究上常使用 1-methyl-4-phenyl-1，2，3，6-tetrahydropyridine (MPTP)引發多 巴胺神經系統退化，以建立巴金森氏症之動物模式，此藥物會造成發炎性細胞激素增加， 但是上述變化並不因接受L-DOPA治療而獲得改善，顯示另有其他機轉媒介上述神經發炎 及神經退化現象。而且目前尚無文獻報告多巴胺神經系統退化與抗發炎性細胞激素 (anti-inflammatory cytokines) IL-4及IL-10的關係。由於某些細胞激素會導致年老動物之 海馬回神經出現退化，干擾動物的空間記憶，而且當神經受到傷害時，會活化微膠細胞釋 放發炎性細胞激素，因此推論發炎性細胞激素可能導致其他腦區一特別是大腦皮質、海馬 回及邊緣系統内之神經出現退化現象，進而引起情緒及認知功能障礙等失智症狀。 大腦皮質的越胺酸神經系統（glutamatergic system)參與許多腦區例如海馬回、顆葉 皮質、中前額葉皮質及頂葉皮質内形成記憶及提取記憶之功能。多巴胺神經系統退化所引 起的發炎性細胞激素會導致皮質内興奮性胺基酸神經活性過高，製造或釋放太多麩胺酸。 越胺酸作用在N-methyl-D-aspartate (NMDA)受體可引起興奮性毒性，導致細胞凋亡。 amantadine是NMDA受體之拮抗劑，可以抑制過度興奮的越胺酸神經活性，保護黑質體内 的神經免於MPTP之破壞，過去數十年來已經被用來治療巴金森氏症，降低運動障礙，臨 床上也用以治療阿茲海默氏失智症。因此吾人推論：多巴胺神經退化會增加發炎性細胞激 素，進而增加麩胺酸神經系統之活性，經由NMDA受體之作用，產生廣泛的神經傷害，進 而誘發失智症。 本研究預計以兩年期間完成下列研究目標：O以MPTP破壞大鼠腦部多巴胺神經系 統，以誘發巴金森氏症動物模式，而後以高腳十字迷宮（elevated plus-maze)測量動物之 情緒行為，並且在開放空間（open field)中進行「物件探索試驗」Object exploration test) 評量動物之認知功能，而後摘取動物之腦組織，以酵素接合免疫吸附法測量海馬回、顳葉 皮質、中前額葉皮質、頂葉皮質及紋狀體内發炎性細胞激素IL-1、IL-2、IL-6、TNF-a與 抗發炎性細胞激素IL-4、IL-10之濃度，而後分析動物行為表現與各腦區内細胞激素之關 係。（2)承續第一年之研究結果，在MPTP注射前及注射後以amantadine藥物操弄越胺酸 神經系統NMDA受體之活性，探討該系統在上述神經退化與情緒、認知功能之角色。（3 ) 上述實驗中每一組均保留至少3至5隻動物的完整大腦，進行切片，以執行免疫組織化學 染色（immunohistochemistry)，測定腦部黑質體與紋狀體内酷■胺酸經化酶（tyrosine hydroxylase)之含量，以碟定MPTP破壞多巴胺神經系統之效果；腦組織切片也將用以測 定微膠細胞活化之狀況，以釐清微膠細胞在上述神經與細胞激素之交互作用的角色。經由 上述三項研究結果以推論經由藥物抑制麩胺酸神經系統之活性，是否經由微膠細胞降低發 炎反應，進而有助於改善巴金森氏症之神經病理機轉及其引發的情緒認知障礙。Project