探討thaliporphine衍生物對於腦缺血離體模式(缺糖、缺氧/再給氧)所引起初代培養大鼠神經細胞死亡之保護作用及機制

Protective effect of thaliporphine derivative on neuronal death induced by glucose-oxygen deprivation/reoxygenation in primary culture of rat brain cells

彭康倫(Kang lun Peng)

指導教授 ： 王家儀

臺北醫學大學/醫學院/醫學科學研究所/碩士(2013年)

摘要

腦組織缺氧 (hypoxia) 或缺血 (ischemia) 會引發一連串複雜的反應，導致細胞損傷，且已有研究報告指出，在恢復期再給氧反而加重缺氧-缺血性損傷的程度 ；而造成這些神經損傷及退化的一個很大的因素，就是氧化壓力 (oxidative stress)。
Thaliporphine係從五掌楠樟科Neolitsea Konishii所萃取的生物鹼，過去文獻已證實在缺血再灌流的動物模式下有抗氧化的能力，而對心臟缺血/再灌流有保護作用。本計劃設計利用初代培養的大腦皮質細胞為材料，由初生的大鼠腦皮質培養的混和神經/膠質細胞 (神經細胞大約佔40%，星狀膠細胞佔45%，微膠細胞佔15%)，評估缺氧、缺糖/再給氧 (Oxygen-Glucose Deprivation/Reoxygenation, OGD/R)對於神經細胞的損傷情形。給予細胞缺氧、缺糖/再給氧 (OGD/R)8小時後再給氧予0、2、4小時，以測量培養液中的乳酸去氫酶 (lactate dehydrogenase, LDH) 的活性，來評估細胞的存活；發現OGD8/R2後細胞存活率明顯下降，而同時給予Thaliporphine衍生物 (TM-1)處理後發現細胞存活率有明顯改善的情形。另外也發現TM-1 (20μM)能夠抑制氧化壓力對於細胞所造成的細胞凋亡情形。TM-1能夠誘發第一型血基質氧化酶 (HO-1)的表現，第一型血基質氧化酶在過去文獻已證實具有抗氧化、抗發炎和抗細胞凋亡的細胞保護的功能，在本
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實驗中發現到同時給予HO-1活性抑制劑SnPP後，發現到TM-1的抗細胞死亡的細胞保護功能受到抑制，這也顯示TM-1之作用至少部分是透過調控HO-1蛋白質及活性來達到抗細胞氧化及抑制細胞死亡。

關鍵字

缺氧 ； 缺糖/再給氧 ； 細胞死亡 ； 細胞凋亡 ； Thaliporphine derivative

並列摘要

Hypoxia/reoxygenation (H/R) or ischemia/reperfusion (I/R) is involved in a wide range of pathophysiological responses. Hypoxic or ischemic insults in the central nervous system (CNS) will cause brain injury and neurological impairment.
Thaliporphine, a phenolic aporphine alkaloid obtained from Chinese herbs, Neolitsea Konishii ,has been shown to afford cardioprotective effects against injury via antioxidant activity. In the present study, we investigated whether TM-1 protects cortical neuron against injury caused by in vitro ischemia (oxygen-glucose deprivation; OGD).
Using neuron/glia co-cultures which comprised of 40% neuron, 45% astrocytes, and 15% microglia, we found that thaliporphine derivatives (TM-1) concentration-dependently protected neuron and glia cells from loss of viability induced by oxygen-glucose deprivation/reoxygenation (OGD/R ). TM-1 (20μM) inhibited the formation of apoptotic nuclei induced by OGD/R. TM-1 could upregulate heme oxygenase-1 (HO-1), a stress protein that is known to play a cyto-protective role against oxidative stress and necrosis. HO-1 has the beneficial effect in oxidative insults such as I/R. Cotreatment with SnPP, an HO-1 activity inhibitor, significantly abolished the cytoprotective effects of TM-1, suggesting that HO-1 plays a crucial role in the neuroprotective effects of TM-1 against OGD/R injury in vitro.

並列關鍵字

OGD/R ； cell death ； apoptosis ； Thaliporphine derivative

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