State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Molecules. 2020 Mar 9;25(5):1225. doi: 10.3390/molecules25051225.
Conjugated linolenic acid (CLNA) is a type of ω-3 fatty acid which has been proven to have a series of benefits. However, there is no study about the function of -derived CLNA isomer. ZS2058 has been proven to manifest comprehensive functions and can produce CLNA. To investigate the specific functions of CLNA produced by this probiotic bacterium, two different conjugated α-linolenic acid (CLNA) isomers were successfully isolated. These isoforms, CLNA1 (c9, t11, c15-CLNA, purity 97.48%) and CLNA2 (c9, t11, t15-CLNA, purity 99.00%), both showed the ability to inhibit the growth of three types of colon cancer cells in a time- and concentration-dependent manner. In addition, the expression of MDA in Caco-2 cells was increased by CLNA1 or CLNA2, which indicated that lipid peroxidation was related to the antiproliferation activity of CLNAs. An examination of the key protein of pyroptosis showed that CLNA1 induced the cleavage of caspase-1 and gasdermin-D, while CLNA2 induced the cleavage of caspase-4, 5 and gasdermin-D. The addition of relative inhibitors could alleviate the pyroptosis by CLNAs. CLNA1 and CLNA2 showed no effect on caspase-3, 7, 9 and PARP-1, which were key proteins associated with apoptosis. No sub-diploid apoptotic peak appeared in the result of PI single staining test. In conclusion, CLNA1 activated caspase-1 and induced Caco-2 cell pyroptosis, whereas CLNA2 induced pyroptosis through the caspase-4/5-mediated pathway. The inhibition of Caco-2 cells by the two isomers was not related to apoptosis. This is the first study on the function of -derived CLNA isomer. The inhibition pathway of -derived CLNA isomer on colon cancer cells were proved.
共轭亚油酸（CLNA）是一种 ω-3 脂肪酸，已被证明具有一系列益处。然而，目前还没有关于 -衍生 CLNA 异构体功能的研究。ZS2058 已被证明具有全面的功能，并能产生 CLNA。为了研究这种益生菌产生的 CLNA 的具体功能，成功分离出两种不同的共轭 α-亚麻酸（CLNA）异构体。这两种异构体，CLNA1（c9，t11，c15-CLNA，纯度 97.48%）和 CLNA2（c9，t11，t15-CLNA，纯度 99.00%），均表现出时间和浓度依赖性抑制三种结肠癌细胞生长的能力。此外，CLNA1 或 CLNA2 增加了 Caco-2 细胞中 MDA 的表达，这表明脂质过氧化与 CLNAs 的抗增殖活性有关。对细胞焦亡关键蛋白的检测表明，CLNA1 诱导了 caspase-1 和 gasdermin-D 的裂解，而 CLNA2 诱导了 caspase-4、5 和 gasdermin-D 的裂解。加入相对抑制剂可减轻 CLNAs 引起的细胞焦亡。CLNA1 和 CLNA2 对 caspase-3、7、9 和 PARP-1 没有影响，这些是与细胞凋亡相关的关键蛋白。在 PI 单染试验结果中没有出现亚二倍体凋亡峰。综上所述，CLNA1 激活 caspase-1 并诱导 Caco-2 细胞发生细胞焦亡，而 CLNA2 通过 caspase-4/5 介导的途径诱导细胞焦亡。两种异构体对 Caco-2 细胞的抑制与细胞凋亡无关。这是首次研究 -衍生 CLNA 异构体的功能。证明了 -衍生 CLNA 异构体对结肠癌细胞的抑制途径。
