CAJ | 학술논문

本试验主要研究了不同浓度的β-羟丁酸( BHBA)对奶牛乳腺上皮细胞( BMECs)活力、甘油三酯( TAG)含量、脂滴形成以及乳脂肪合成相关基因转录水平的影响。将传至第3代的BMECs悬液(1×105个/孔)接种于细胞培养板上,每孔加入含10%胎牛血清( FBS)的DMEM/F12培养液,于37℃的5%二氧化碳(CO2)培养箱培养48 h。再将培养48 h的BMECs随机分配到6个组,各组向培养孔中加入含不同浓度BHBA的DMEM/F12培养液,培养液中的FBS用1 g/L无脂肪酸的牛血清白蛋白( BSA)代替,并使反应体系中BHBA的最终浓度分别为0(对照)、0.58、1.16、2.32、4.64和9.28 mmol/L。置于37℃的5%CO2培养箱继续培养48 h。试验结果显示：随着BHBA浓度的增加,BMECs活力[(相对增殖率( RGR)]呈显著的二次曲线增加(P=0.041),其中BMECs活力以0.58~4.64 mmol/L BHBA组较高,9.28 mmol/L BHBA组较低；低浓度(0.58~2.32 mmol/L)的 BHBA 可促进 BMECs 内脂滴的形成,而较高浓度(4.64~9.28 mmol/L)的BHBA对脂滴形成的促进作用减弱；BHBA与TAG含量及乳脂肪合成相关基因脂肪酸合成酶( FASN )、乙酰辅酶 A 羧化酶α( ACACA )、硬脂酰辅酶 A 去饱和酶( SCD)、脂肪酸结合蛋白3( FABP3)、过氧化物酶体增殖物激活受体γ( PPARG)和分化抗原簇36(CD36)的相对表达量均无显著的一次线性或二次曲线关系(P>0.05)。综上,BHBA 对BMECs活力的促进作用呈显著的二次曲线增加,即BHBA对BMECs活力呈显著浓度依赖关系；BHBA对细胞内乳脂肪的合成有提高的趋势。
본시험주요연구료불동농도적β-간정산( BHBA)대내우유선상피세포( BMECs)활력、감유삼지( TAG)함량、지적형성이급유지방합성상관기인전록수평적영향。장전지제3대적BMECs현액(1×105개/공)접충우세포배양판상,매공가입함10%태우혈청( FBS)적DMEM/F12배양액,우37℃적5%이양화탄(CO2)배양상배양48 h。재장배양48 h적BMECs수궤분배도6개조,각조향배양공중가입함불동농도BHBA적DMEM/F12배양액,배양액중적FBS용1 g/L무지방산적우혈청백단백( BSA)대체,병사반응체계중BHBA적최종농도분별위0(대조)、0.58、1.16、2.32、4.64화9.28 mmol/L。치우37℃적5%CO2배양상계속배양48 h。시험결과현시：수착BHBA농도적증가,BMECs활력[(상대증식솔( RGR)]정현저적이차곡선증가(P=0.041),기중BMECs활력이0.58~4.64 mmol/L BHBA조교고,9.28 mmol/L BHBA조교저；저농도(0.58~2.32 mmol/L)적 BHBA 가촉진 BMECs 내지적적형성,이교고농도(4.64~9.28 mmol/L)적BHBA대지적형성적촉진작용감약；BHBA여TAG함량급유지방합성상관기인지방산합성매( FASN )、을선보매 A 최화매α( ACACA )、경지선보매 A 거포화매( SCD)、지방산결합단백3( FABP3)、과양화물매체증식물격활수체γ( PPARG)화분화항원족36(CD36)적상대표체량균무현저적일차선성혹이차곡선관계(P>0.05)。종상,BHBA 대BMECs활력적촉진작용정현저적이차곡선증가,즉BHBA대BMECs활력정현저농도의뢰관계；BHBA대세포내유지방적합성유제고적추세。
This study was conducted to determine the effects ofβ-hydroxybutyric acid ( BHBA) on cell viabili-ty, triacylglycerol ( TAG) content, lipid droplet formation and relative expression levels of genes related to milk fat synthesis in bovine mammary epithelial cells (BMECs). The 3th passage cells were plated 1×105 cells/well in culture plates and DMEM/F12 medium containing 10% fetal bovine serum ( FBS) was added to each well, then the plates were maintained in an incubator with 5% CO2 at 37 ℃. After 48 h, cells were ran-domly divided into 6 groups and cultured in DMEM/F12 medium containing different concentrations of BH-BA, FBS in medium was replaced with 1 g/L fatty acid-free bovine serum albumin ( BSA) . The final concen-trations of BHBA in reaction systems were 0 ( control) , 0.58, 1.16, 2.32, 4.64, 9.28 mmol/L, respectively. Continuous incubation in an incubator with 5% CO2 at 37℃ for 48 h. The results showed that BMECs prolifer-ation [ relative growth rate ( RGR) ] was significantly quadratic increased with BHBA concentration increasing (P=0.041), and BMECs proliferation of 0.58 to 4.64 mmol/L BHAB groups was high, but 9.28 mmol/L BHBA group was low. BHBA at low concentration (0.58 to 2.32 mmol/L) promoted lipid droplet formation, and the promoting effect of BHBA at high concentration (4.64 to 9.28 mmol/L) was weakened. No significant linear and quadratic relationships were found between BHBA concentration and TAG content (P>0.05). No significant linear and quadratic relationships were found between BHBA concentration and relative expression levels of genes related to milk fat synthesis ( fatty acid synthetase, acetyl-CoA carboxylaseα, stearyl coenzyme A desaturase, fatty acid binding protein 3, peroxisome proliferator-activated receptorγand cluster of differenti-ation 36) ( P>0.05) . In conclusion, BMECs proliferation significantly quadratic increase with BHBA concen-tration increasing, namely BMECs proliferation has significant concentration-dependent relationship with BHBA concentration, and the milk fat synthesis has a improve trend by BHBA concentration.