油酸处理对MGN3-1细胞饥饿素分泌的影响及机制

doi:10.11843/j.issn.0366-6964.2025.09.045

摘要/Abstract

摘要： 本研究旨在探究油酸(OA)处理对饥饿素(ghrelin)分泌的影响及其相关机制。分别以OA及GPR120抑制剂(AH-7614)处理MGN3-1细胞(胃饥饿素瘤细胞)进行试验：1)确定OA的处理条件并分组；2)ELISA法检测细胞上清中酰化饥饿素(AG)的含量；RT-qPCR检测各组细胞内ghrelin、GOAT(生长素释放肽O-酰基转移酶)、GPR120(长链脂肪酸受体)和ACCα(乙酰辅酶A羧化酶)的基因表达；Western blot检测细胞内GPR120、PKC、IP3R的蛋白表达；流式细胞术检测细胞内Ca²⁺ 浓度。结果表明：1)确定OA处理的低、中、高浓度分别为20、40、60 μmol·L^-1，处理时间为8 h；2)高浓度OA处理，极显著下调了细胞ghrelin和GOAT的基因表达并降低了AG的分泌水平(P＜0.01)，极显著升高了Ca²⁺浓度(P＜0.01)，显著或极显著上调了GPR120和ACCα的基因表达及GPR120、IP3R和PKC的蛋白表达(P＜0.05或P＜0.01)；AH-7614处理显著或极显著上调了GOAT和ghrelin的基因表达及IP3R的蛋白表达，升高AG分泌水平，下调GPR120和ACCα的基因表达及GPR120和PKC的蛋白表达(P＜0.05或P＜0.01)；与AH-7614处理组相比，用AH-7614处理后再用OA处理，AG分泌水平及ghrelin和GOAT基因表达水平显著或极显著降低(P＜0.05或P＜0.01)，GPR120和ACCα的基因表达及GPR120、IP3R和PKC的蛋白表达均有一定程度上调。综上，OA处理可以减少MGN3-1细胞ghrelin的分泌。其可能的机制为OA处理一方面通过激活GPR120及其下游PKC/IP3/Ca²⁺信号通路，另一方面通过上调ACCα的表达，激活脂肪酸β-氧化，使酰基辅酶A产生增多，两条通路协同抑制GOAT活性，使细胞ghrelin分泌减少，AG产生减少。

关键词: 油酸, 饥饿素, MGN3-1细胞, 分泌, 机制

Abstract: The aim of this study was to investigate the effect of oleic acid (OA) treatment on the secretion of ghrelin and its related mechanisms. MGN3-1 cells (gastric starvation tumor cells) were treated with OA and GPR120 inhibitor (AH-7614), respectively, and the following experiments were performed: 1) Determine the processing conditions for OA and group them together; 2) the amount of acylated starvation hormone (AG) was detected in the supernatant of the cells by ELISA; RT-qPCR was used to detect the gene expression of ghrelin, GOAT (growth hormone-releasing peptide O-acyltransferase), GPR120 (long-chain fatty acid receptor), and ACCα (acetyl-coenzyme A carboxylase) in the cells of each group; Western blot was used to detect the protein expression of GPR120, PKC, and IP3R; and flow cytometry was used to detect the intracellular Ca²⁺ concentration. The results showed that: 1) The low, medium and high concentrations of OA were determined to be 20, 40 and 60 μmol·L^-1, respectively, and the treatment time was 8 h. 2) The treatment of high concentration of OA highly significantly down-regulated cellular ghrelin and GOAT gene expression and decreased AG secretion (P<0.01), significantly increased Ca²⁺ concentration (P<0.01), significantly or highly significantly up-regulated gene expression of GPR120 and ACCα and protein expression of GPR120, IP3R and PKC (P<0.01 or P<0.05); AH-7614 treatment significantly or highly up-regulated the gene expression of GOAT and ghrelin and protein expression of IP3R, elevated AG secretion levels, and down-regulated GPR120 and ACCα gene expression and protein expression of GPR120 and PKC(P<0.01 or P<0.05); in contrast to the AH-7614 group, treatment with AH-7614 followed by OA resulted in significant or highly significant reduction in AG secretion levels and ghrelin and GOAT gene expression levels(P<0.01 or P<0.05), and a certain degree of up-regulation of the expression of GPR120 and ACCα genes as well as of the protein expression of GPR120, IP3R and PKC. In conclusion, the results suggest that OA treatment reduced ghrelin secretion in MGN3-1 cells. The possible mechanism is that OA treatment inhibition of GOAT activity through activation of GPR120 and its downstream PKC/IP3R/Ca²⁺signaling pathway on the one hand, and activating fatty acid β-oxidation through up-regulation of ACCα expression on the other hand, the two pathways synergistically inhibit GOAT activity, resulting in decreased cellular ghrelin secretion and reduced AG production.

Key words: oleic acid (OA), ghrelin, MGN3-1 cells, secretion, mechanism

中图分类号:

S852.23

徐佳靖, 李林, 杜欣雨, 陈希文, 王公民, 张源淑. 油酸处理对MGN3-1细胞饥饿素分泌的影响及机制[J]. 畜牧兽医学报, 2025, 56(9): 4686-4697.

XU Jiajing, LI Lin, DU Xinyu, CHEN Xiwen, WANG Gongmin, ZHANG Yuanshu. Effect and Mechanism of Oleic Acid Treatment on the Secretion of Ghrelin in MGN3-1 Cells[J]. Acta Veterinaria et Zootechnica Sinica, 2025, 56(9): 4686-4697.

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