Ngo Dai-Hung, Kang Kyong-Hwa, Ryu BoMi, Vo Thanh-Sang, Jung Won-Kyo, Byun Hee-Guk, Kim Se-Kwon
Marine Bioprocess Research Center, Pukyong National University, Busan 608-739, Republic of Korea.
School of Pharmacy, The University of Queensland, Brisbane, QLD 4072, Australia.
Food Chem. 2015 May 1;174:37-43. doi: 10.1016/j.foodchem.2014.11.013. Epub 2014 Nov 8.
The aim of this study was to investigate antihypertensive effect of bioactive peptides from skate (Okamejei kenojei) skin gelatin. The Alcalase/protease gelatin hydrolysate below 1 kDa (SAP) exhibited the highest angiotensin-I converting enzyme (ACE) inhibition compared to other hydrolysates. SAP can decrease systolic blood pressure significantly in spontaneously hypertensive rats. SAP inhibited vasoconstriction via PPAR-γ expression, activation and phosphorylation of eNOS in lungs. Moreover, the expression levels of endothelin-1, RhoA, α-smooth muscle actin, cleaved caspase 3 and MAPK were decreased by SAP in lungs. Vascularity, muscularization and cellular proliferation in lungs were detected by immunohistochemical staining. Finally, two purified peptides (LGPLGHQ, 720Da and MVGSAPGVL, 829Da) showed potent ACE inhibition with IC50 values of 4.22 and 3.09 μM, respectively. These results indicate that bioactive peptides isolated from skate skin gelatin may serve as candidates against hypertension and could be used as functional food ingredients.
本研究旨在探讨孔鳐（Okamejei kenojei）皮明胶生物活性肽的降压作用。与其他水解产物相比，分子量低于1 kDa的碱性蛋白酶/蛋白酶明胶水解产物（SAP）表现出最高的血管紧张素I转换酶（ACE）抑制活性。SAP可显著降低自发性高血压大鼠的收缩压。SAP通过肺组织中PPAR-γ的表达、eNOS的激活和磷酸化抑制血管收缩。此外，SAP可降低肺组织中内皮素-1、RhoA、α-平滑肌肌动蛋白、裂解的半胱天冬酶3和丝裂原活化蛋白激酶的表达水平。通过免疫组织化学染色检测肺组织中的血管生成、肌化和细胞增殖。最后，两种纯化的肽（LGPLGHQ，720 Da和MVGSAPGVL，829 Da）表现出较强的ACE抑制活性，IC50值分别为4.22和3.09 μM。这些结果表明，从孔鳐皮明胶中分离得到的生物活性肽可能是抗高血压的候选物质，可作为功能性食品成分。
