硬脂酸对奶山羊乳腺上皮细胞活力和乳脂合成的影响

doi:10.16431/j.cnki.1671-7236.2025.02.008

摘要/Abstract

摘要： 【目的】探索不同浓度硬脂酸对奶山羊乳腺上皮细胞(GMECs)活力和乳脂合成的影响。【方法】以体外培养的GMECs为试验材料，采用不同浓度的硬脂酸(0、12.5、25、50、100、200 μmol/L)处理GMECs 36 h后，通过CCK-8法检测其对细胞活力的影响，采用细胞甘油三酯检测试剂盒检测其对细胞甘油三酯含量的影响；选择对细胞活力无抑制作用的最大浓度硬脂酸处理GMECs，油红O染色法检测硬脂酸对细胞中脂滴聚积的影响；采用实时荧光定量PCR检测乳脂合成相关基因mRNA水平的变化。【结果】硬脂酸浓度在0～100 μmol/L范围时对细胞活力无显著影响(P>0.05)，而当硬脂酸浓度为200 μmol/L时GMECs的活力显著低于对照组(P＜0.05)。与对照组相比，100 μmol/L硬脂酸组GMECs内甘油三酯含量和脂滴聚积量显著或极显著增加(P＜0.05；P＜0.01)。实时荧光定量PCR结果表明，与对照组相比，100 μmol/L硬脂酸处理后，GMECs内白细胞分化抗原36(CD36)和二酰甘油-O-酰基转移酶同源物1(DGAT1)基因mRNA表达量极显著或显著升高(P＜0.01；P＜0.05)；心脏型脂肪酸结合蛋白3(FABP3)、硬脂酰辅酶A去饱和酶1(SCD1)、脂肪甘油三酯脂肪酶(ATGL)和叉头框转录因子O1(FoxO1)基因的mRNA表达量极显著或显著降低(P＜0.01；P＜0.05)，而脂肪酸合成酶(FASN)和固醇调节元件结合蛋白1(SREBF1)基因的mRNA表达无显著影响(P＞0.05)。【结论】 100 μmol/L硬脂酸能通过调控乳脂代谢相关基因的表达，促进GMECs内甘油三酯合成及脂滴分泌。本研究为外源添加长链脂肪酸调控乳脂合成代谢提供参考，对进一步提高奶山羊泌乳性能和乳品质具有重要意义。

关键词: 奶山羊; 硬脂酸; 乳腺上皮细胞; 乳脂合成

Abstract: 【Objective】 The aim of this study was to explore the effects of different concentrations of stearic acid on the viability and milk fat synthesis of goat mammary epithelial cells (GMECs). 【Method】 Firstly,GMECs were cultured in vitro and treated with different doses of stearic acid (0,12.5,25,50,100 and 200 μmol/L) for 36 h,the effect on cell viability was detected by CCK-8 method,and the effect on cell triglyceride content was detected by cell triglyceride detection kit.The maximum concentration of stearic acid that had no inhibitory effect on cell viability was chose to treat cells,the effect of stearic acid on lipid droplet accumulation of GMECs were detected by oil red O staining.The mRNA expression levels of genes related to milk fat synthesis were detected by Real-time quantitative PCR. 【Result】 When the concentration of stearic acid was in the range of 0-100 μmol/L,it had no significant effect on cell viability (P>0.05),but when the concentration of stearic acid was 200 μmol/L,the activity of GMECs was significantly lower than that of the control group (P＜0.05).Compared with the control group,the triglyceride content and lipid droplet accumulation in GMECs of the 100 μmol/L stearic acid group were significantly or extremely significantly increased (P＜0.05 or P＜0.01).The Real-time quantitative PCR results showed that compared with the control group,after treatment with 100 μ mol/L stearic acid,the mRNA expression levels of cluster of differentiation 36 (CD36) and diacylglycerol O-acyltransferase homolog 1 (DGAT1) were extremely significantly or significantly increased (P＜0.01 or P＜0.05),The mRNA expression levels of heart-type fatty acid binding protein 3 (FABP3),stearoyl-CoA desaturase 1 (SCD1),adipose triglyceride lipase (ATGL) and forkhead box transcription factor O1 (FoxO1) were extremely significantly or significantly reduced (P＜0.01 or P＜0.05),while the mRNA expression levels of fatty acid synthase (FASN) and sterol-regulatory element binding protein 1 (SREBF1) genes were not significantly affected (P＞0.05). 【Conclusion】 100 μmol/L stearic acid could promote the synthesis of triglycerides and lipid droplet secretion in GMECs by regulating the expression of genes related to milk fat metabolism.This study provided a reference for exogenous addition of long-chain fatty acids to regulate milk fat synthesis and metabolism,which was of great significance for further improving the lactation performance and milk quality of dairy goats.

Key words: dairy goat; stearic acid; mammary epithelial cells; milk fat synthesis

中图分类号:

S827

李君, 余倩倩, 李佳琳, 李忠莹, 韩浩园, 施会彬, 刘昆, 张浩, 权凯. 硬脂酸对奶山羊乳腺上皮细胞活力和乳脂合成的影响[J]. 中国畜牧兽医, 2025, 52(2): 574-581.

LI Jun, YU Qianqian, LI Jialin, LI Zhongying, HAN Haoyuan, SHI Huibin, LIU Kun, ZHANG Hao, QUAN Kai. Effects of Stearic Acid on Cell Viability and Milk Fat Synthesis in Goat Mammary Epithelial Cells[J]. China Animal Husbandry and Veterinary Medicine, 2025, 52(2): 574-581.

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