Yang Ru-Qing, Chen Yu-Lei, Lin Duanquan, Cao Kai-Yuan, Sun Le-Chang, Zhang Ling-Jing, Yoshida Asami, Cao Min-Jie
College of Ocean Food and Biological Engineering, Jimei University, Xiamen 361021, China.
Collaborative Innovation Center of Marine Food Deep Processing, Dalian Polytechnic University, Dalian 116034, China.
J Agric Food Chem. 2024 Oct 5. doi: 10.1021/acs.jafc.4c04461.
Matrix metalloproteinases (MMPs) play critical roles in the degradation of collagens, while their mechanism remains unclear. In the present study, the involvement of matrix metalloproteinases (MMPs) in collagen degradation of sea bass muscle during cold storage was explored. Immunohistochemical staining results showed significant degradation of type I collagen in the connective tissue of muscle endomysium during cold storage, thus affecting the muscle structural integrity and quality. Western blot analysis revealed an increment in the α1 chain and a decrease in the β and γ chains of type I collagen. Immunofluorescence staining showed that MMP-2, MMP-9, and MMP-13 were distributed in the endomysium surrounding the muscle fibers. Additionally, the catalytic domains of MMP-2, MMP-9, and MMP-13 with biological activities were successfully expressed. The degradation trend of type I collagen by MMPs under 4 °C was similar to that of muscle collagen during cold storage, suggesting that the degradation of type I collagen was attributed to the cooperative action of the MMPs. In conclusion, our study elucidated that the MMPs-engaged degradation of type I collagen is quite possibly the leading cause of sea bass muscle softening during cold storage.
基质金属蛋白酶（MMPs）在胶原蛋白降解过程中发挥着关键作用，但其机制仍不清楚。在本研究中，探讨了基质金属蛋白酶（MMPs）在鲈鱼肌肉冷藏期间胶原蛋白降解中的作用。免疫组织化学染色结果显示，冷藏期间肌内膜结缔组织中的I型胶原蛋白显著降解，从而影响肌肉结构完整性和品质。蛋白质免疫印迹分析显示I型胶原蛋白的α1链增加，β链和γ链减少。免疫荧光染色显示MMP-2、MMP-9和MMP-13分布在肌纤维周围的肌内膜中。此外，成功表达了具有生物活性的MMP-2、MMP-9和MMP-13的催化结构域。4℃下MMPs对I型胶原蛋白的降解趋势与肌肉冷藏期间胶原蛋白的降解趋势相似，表明I型胶原蛋白的降解归因于MMPs的协同作用。总之，我们的研究表明，MMPs介导的I型胶原蛋白降解很可能是鲈鱼肌肉冷藏期间软化的主要原因。
