論文名稱:

檳榔嚼塊成份對口腔上皮細胞轉錄因子NF-kB活性之調控

 

The regulation of NF-kB activity by areca quid ingredients in human oral keratinocytes

研究生:

李思穎  Szu-Ying Lee

 

(以作者名查詢陽明大學館藏系統)

 

(以作者名查詢全國圖書書目資訊網)

指導教授:

林姝君  Shu-Chun Lin

        學位類別:

碩士

        學校名稱:

國立陽明大學

系所名稱:

口腔生物研究所

            學號:

39017009

          學年度:

91

          語文別:

中文

          出版年:

92

全文說明:

電子全文

        論文頁數:

67

摘要:

  根據流行病學的資料顯示,咀嚼檳榔嚼塊與台灣口腔癌的發生有密切關係。台灣檳榔嚼塊主要是由檳榔子、荖花(或荖葉)及石灰所組成。已知檳榔子水萃取液對多種型態細胞具有細胞毒性以及基因毒性;而每公克荖花中含有約15.4 mg黃樟素,因此在嚼食荖花檳榔塊過程中,口腔將暴露於大量黃樟素中(唾液中可測得黃樟素濃度為420 μM)。然而目前檳榔參與口腔癌化過程之分子證據仍未明瞭,因此本研究即是針對檳榔子水萃取液與黃樟素對於口腔上皮中NF-kB活性之調控做一探討。

 

  首先探討在檳榔子水萃取液處理過後,口腔上皮細胞中NF-kB的活化情形。電泳移動性實驗結果說明,OECM-1OC3細胞中的NF-kB活性都會被檳榔子水萃取液所調控,但活化程度以及活性出現的時間點並不相同。檳榔子水萃取液刺激OECM-1細胞後所誘導出具活性之NF-kB次單元體,主要是以p50p65最多,其次是p75(c-Rel)p68(RelB)。另外,也發現NF-kB活性抑制劑PDTC可以阻斷檳榔子水萃取液在OECM-1細胞中所引起之NF-kB活性。正常人類口腔細胞NHOKNF-kB活性也會被檳榔子水萃取液所調控,若以檳榔子水萃取液長時間處理NHOK細胞則發現,可與含kB序列之DNA探針結合的NF-kB蛋白質複合物成份將隨細胞繼代數之增加而改變。

 

  在黃樟素的實驗方面,以黃樟素濃度0400μM處理OECM-1OC3細胞218小時後,OECM-1細胞中NF-kB活性雖在某些劑量或時間點有增加,但其增加之幅度都不甚明顯。而OC3細胞中所測到的活性更是幾乎沒有變化。

 

  最後,本論文將NHOK細胞同時處理EGCG和檳榔子水萃取液兩種藥物,結果發現EGCG將會改變檳榔子水萃取液在NHOK細胞中所誘導出之NF-kB蛋白質複合物成份。

 

    Epidemiological studies showed that betel quid (BQ) chewing is the main cause of oral squamous cell carcinoma (OSCC) in Taiwan. The most popular way to chew BQ in Taiwan is to combine areca nut, Piper betel inflorescence (or the betel leaf), and lime paste. Areca nut extract (ANE) exerts cytotoxicity and genotoxicity to several types of cells. In every gram of Piper betel inflorescence contains a high concentration of 15.4 mg safrole. As a result, chewing BQ containing Piper betel inflorescence may result in high safrole (420 μM in saliva during chewing) exposure. However, the molecular evidence of areca in oral tumorigenesis is still not clear. In this study, the NF-kB activity in oral cells after ANE or safrole treatment was examined.

 

    The NF-kB activity in oral cells after ANE treatment was first investigated. The results of electrophoretic mobility shift assay (EMSA) illustrated that the NF-kB activity could be up-regulated by ANE in OECM-1 and OC3 cell lines. The induction levels and the appearance of time points were different between two cell lines. The main NF-kB subunits expressed in OECM-1 was p50 and p65, and the minor components were p75 (c-Rel) and p68 (RelB). Furthermore, it was found that the NF-kB inhibitor, PDTC, blocked the NF-kB activity induced by ANE in OECM-1 cells. The NF-kB activity in normal human keratinocytes (NHOK) could also be up-regulated by ANE. This study showed that, in NHOK cells, the components of NF-kB complex were altered after a long-term ANE treatment.

 

    When OECM-1 and OC3 cells were treated with safrole 0400 μM for 218 hours, NF-kB was activated at certain different levels of dosage or time points, but the level increased was not significant. However, NF-kB activity was not regulated by ANE in OC3 cells.

 

    Finally, when NHOK was treated with EGCG and ANE simultaneously, it was found that the NF-kB components induced by ANE in NHOK was changed by EGCG.