Regulatory Mechanisms of Bronchial Asthma and Tracheal Epithelial Stabilization by Phytochemicals

2021 Fiscal Year Final Research Report

• Project/Area Number: 17K11899
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Surgical dentistry
• Research Institution: Tokyo Medical and Dental University
• Principal Investigator: Wakita Ryo 東京医科歯科大学, 大学院医歯学総合研究科, 准教授 (60376712)
• Co-Investigator(Kenkyū-buntansha): 船山 ひろみ 鶴見大学, 歯学部, 講師 (00359530)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: フィトケミカル / 気管支平滑筋 / kushenol / カルシウムイオン / 気管上皮

Outline of Final Research Achievements

Pretreatment of bronchial smooth muscle cells with kushenol, a compound of Sophora flavescens, resulted in inhibition of intracellular calcium ion concentrations, but suppression of prostaglandin receptors did not attenuate this effect. Considering studies using other herbal herb-derived ingredients, we focused on phosphokinase A (PKA) activation in bronchial smooth muscle cells treated with supernatant of tracheal epithelial cells that were exposed to kushenol, but we did not find any obvious effect. As a guide to PKA activation, we have changed the target to other proteins to confirm the results, but it is also possible that the pathways mediated by phosphokinase C or inositol 3-phosphate are being inhibited. We are planning to examine calcium ion concentrations in the sarcoplasmic reticulum as well as PLC activity.

Free Research Field

歯科麻酔学

Academic Significance and Societal Importance of the Research Achievements

漢方に使用される生薬はハーブとともに代替医療の有力な候補とされており、その薬理効果の解析にも注目が集まっている。その一つである苦参には上皮・粘膜抗炎症作用の報告があり、苦参を含む生薬合剤は気管支収縮を抑制することが報告されている。苦参のフィトケミカルであるkushenolの気管支平滑筋に対する直接作用は判明したが、その機序および気管上皮を介した間接作用は既知の生薬成分とは異なり未だ検索の途中にある。本研究の意義は、気管支収縮への調節機構が判明することで、従来は症状の安定化が困難だった気管支喘息への新しい選択肢となりうることにある。