運用奈米點陣列調控心肌細胞eNOs表現

Abstract

過去曾探討拓撲(Topography)對細胞行為的影響，但對於長時間的生物因子影響卻很少涉及，像是生物相容性、發炎等等...因子。 一氧化氮(簡稱NO)是一種高活性的含氮基團，也是細胞發炎和凋亡的生物重要指標。我們試圖探討心肌細胞(H9c2)的誘導型一氧化氮合酶（iNOS）和內皮型一氧化氮合酶（eNOS）的訊號傳遞途徑。利用不同大小的奈米點(10-200nm)，進而去刺激心肌細胞(H9c2)的凋亡和發炎的程度。 在本研究中，在1、3、5、7和14天，培養在奈米點陣列上的細胞，產生一氧化氮的含量，會隨著時間變化。另外，隨著時間的推移，培養在100和200奈米上的心肌細胞，與平面相比，產生一氧化氮的含量有顯著增加。在心肌細胞的eNOS路徑基因中，觀察到類似的趨勢，並且在eNOs的蛋白質表現和螢光免疫染色，亦觀察到相同結果，所以更加確認eNOS路徑，受到奈米點調控。 結果發現100 和 200奈米點陣列，會引發細胞發炎和凋亡的反應(一氧化氮水平)。 綜合上面所述，奈米點陣列會控制細胞凋亡和發炎反應。我們可以透過不同大小的奈米點，長時間調控發炎反應和心血管疾病系統的相關功能蛋白質的表達。這篇研究也提供未來心血管植入物設計的參考。

Topography was been reported to infuence the cells' behavior. However, it is very challenging to know long term biological effects from each individual contributing factor such as biocompatibility, inflammatory and apoptosis. Nitric oxide (NO) is a highly reactive nitrogen radical implicated in inflammatory responses. We investigated the signaling pathway involved in inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOs) in cultured cardiomyoblast H9c2 . Here we propose that the surface topology in contact with the living cells could be designed to control apoptosis and inflammation level such cells. The cardiomyoblast H9c2 was cultured on nanodot arrays with dot diameters ranging between 10 and 200 nm. In the present study, fluctuation of NO production is modulated by nanodot arrays in H9c2 with 1, 3, 5, 7, 14 days culture. With time course, the cell NO level in H9c2 increased with 100 to 200 nm nanodot arrays compared to the flat surface. A similar trend of eNOs signal gene expression was observed in H9c2. We also confirm of the topological control of eNOs pathway. Immunostaining indicated that nanodots lager than 50-nm induced cell eNOs expression. This suggests that nanodots of 100- and 200-nm triggered inflammatory stress response (NO level). In summary, nanotopography controls cell apoptosis and inflammatory responses. By adjusting the nanodot diameter, we could modulate the inflammatory response and expression of function-related genes and proteins in the cardiovascular cell system. The nanotopography mediated control of cell inflammatory and appotosis provides potential insight for designing cardiovascular implants.