Effects of Prolactin and Leptin on Gene Expressions of Milk Proteins and Key Factors Related to Milk Protein Synthesis of Bovine Mammary Epithelial Cells

DU Ruiping; WANG Chunyan; ZHANG Xingfu; GAO Min

doi:10.3969/j.issn.1006-267x.2015.12.034

2015 , Vol. 27 >Issue 12: 3920 - 3930

DOI: https://doi.org/10.3969/j.issn.1006-267x.2015.12.034

SHORT COMMUNICATIONS

Effects of Prolactin and Leptin on Gene Expressions of Milk Proteins and Key Factors Related to Milk Protein Synthesis of Bovine Mammary Epithelial Cells

DU Ruiping ,
WANG Chunyan ,
ZHANG Xingfu ,
GAO Min

Expand

Animal Nutrition Institute of Agriculture and Animal Husbandry Academy of Inner Mongolia, Huhhot 010031, China

Received date: 2015-06-26

Online published: 2015-12-14

Fold

Abstract

This experiment was conducted to investigate the effects of prolactin and leptin on gene expressions of milk proteins and key factors related to milk protein synthesis of bovine mammary epithelial cells under primary culture condition. The primary bovine mammary epithelial cells(pBMECs) were cultured by collagenase digestion. The epithelial origin of pBMECs was identified by morphological observation, growth curve assay and specific milk protein gene expressions detection. There were four treatments with four concentrations of prolactin(0, 0.1, 1.0 and 10.0μg/mL, respectively), leptin concentration was the same(100 ng/mL), and each treatment had six replicates. Thiazole blue(MTT) assay was used to detected the effects of prolactin and leptin on cells proliferation, and real time PCR was used to assay the effects of prolactin and leptin on gene expressions of main milk proteins[α-casein, β-casein, κ-casein and β-lactoglobulin(β-LGB)], Janus kinase 2(JAK2), signal transduction and transcription activator 5(STAT5) and mammalian target of rapamycin(mTOR). The results showed that based on certain concentration of leptin(100 ng/mL), compared with 0μg/mL prolactin treatment:the treatments of 0.1 and 1.0μg/mL prolactin significantly promoted pBMECs proliferation(P<0.05); the treatments of 0.1 and 10.0μg/mL prolactin significantly decreased the gene expressions of αs1-casein, αs2-casein, β-casein and β-LGB(P<0.05); the treatment of 1.0μg/mL prolactin significantly increased the gene expressions of αs1-casein, κ-casein, β-LGB(P<0.05); all supplemental treatments of prolactin exerted promotion effects on JAK2 gene expression(P<0.05); only the treatment of 1.0μg/mL prolactin significantly increased STAT5 and mTOR gene expressions(P<0.05). In conclusion, based on 100 ng/mL leptin in culture medium, positive effects of prolactin on gene expressions of milk proteins and key factors related to milk protein synthesis are observed, but the concentration should be limited in a certain range(0.1 to 1.0μg/mL), and reverse inhibition effects emerge with high or low concentration. Our finding suggests that 100 ng/mL leptin and 1.0μg/mL prolactin show significant promotion effects on gene expressions of milk proteins and key factors related to milk protein synthesis by regulating the gene expressions of signal factors of JAK2, STAT5 and mTOR.

Key words： prolactin; leptin; bovine mammary epithelial cell; milk protein gene; signal pathway factor

Cite this article

DU Ruiping , WANG Chunyan , ZHANG Xingfu , GAO Min . Effects of Prolactin and Leptin on Gene Expressions of Milk Proteins and Key Factors Related to Milk Protein Synthesis of Bovine Mammary Epithelial Cells[J]. Chinese Journal of Animal Nutrition, 2015 , 27(12) : 3920 -3930 . DOI: 10.3969/j.issn.1006-267x.2015.12.034

References

[1] FRIEDMAN J M,HALAAS J L.Leptin and the regulation of body weight in mammals[J].Nature,1998,395(6704):763-770.

[2] GRONER B.Transcription factor regulation in mammary epithelial cells[J].Domestic Animal Endocrinology,2002,23(1/2):25-32.
[3] MOSCHOS S,CHAN J L,MANTZOROS C S.Leptin and reproduction:a review[J].Fertility and Sterility,2002,77(3):433-444.

[4] ROH S G,BAIK M G,CHOI Y J,et al.The effect of lactogenic hormones on protein synthesis and amino acid uptake in rat mammary acinar cell culture at various physiological stages[J].International Journal of Biochemistry,1994,26(4):479-485.

[5] JANSSON N,GREENWOOD S L,JOHANSSON B R,et al.Leptin stimulates the activity of the system A amino acid transporter in human placental villous fragments[J].The Journal of Clinical Endocrinology & Metabolism,2003,88(3):1205-1211.

[6] QIAN L,LOPEZ V,SEO Y A,et al.Prolactin regulates ZNT2 expression through the JAK2/STAT5 signaling pathway in mammary cells[J].American Journal of Physiology:Cell Physiology,2009,297(2):C369-C377.
[7] BROCKMAN J L,SCHROEDER M D,SCHULER L A.PRL activates the cyclin D1 promoter via the JAK2/STAT pathway[J].Molecular Endocrinology,2002,16(4):774-784.

[8] ZHANG Y,PROENCA R,MAFFEI M,et al.Positional cloning of the mouse obese gene and its human homologue[J].Nature,1994,372(6505):425-432.

[9] YANAGIHARA N,UTSUNOMIYA K,CHEAH T B,et al.Characterization and functional role of leptin receptor in bovine adrenal medullary cells[J].Biochemical Pharmacology,2000,59(9):1141-1145.

[10] CHELIKANI P K,GLIMM D R,KENNELLY J J.Short Communication:tissue distribution of leptin and leptin receptor mRNA in the bovine[J].Journal of Dairy Science,2003,86(7):2369-2372.

[11] FEUERMANN Y,MABJEESH S J,SHAMAY A.Leptin affects prolactin action on milk protein and fat synthesis in the bovine mammary gland[J].Journal of Dairy Science,2004,87(9):2941-2946.

[12] FEUERMANN Y,MABJEESH S J,SHAMAY A.Mammary fat can adjust prolactin effect on mammary epithelial cells via leptin and estrogen[J].International Journal of Endocrinology,2009,2009:427260.
[13] 王春艳,杜瑞平,高民,等.Leptin对奶牛乳腺上皮细胞主要乳蛋白基因表达的影响[J].中国畜牧杂志,2013,49(15):58-61.
[14] MIRANDA S G,WANG Y J,PURDIE N G,et al.Selenomethionine stimulates expression of glutathione peroxidase 1 and 3 and growth of bovine mammary epithelial cells in primary culture[J].Journal of Dairy Science,2009,92(6):2670-2683.

[15] BIONAZ M,LOOR J J.Gene networks driving bovine mammary protein synthesis during the lactation cycle[J].Bioinformatics and Biology Insights,2011,5:83-98.
[16] AKERS R M.Major advances associated with hormone and growth factor regulation of mammary growth and lactation in dairy cows[J].Journal of Dairy Science,2006,89(4):1222-1234.

[17] FREEMAN M E,KANYICSKA B,LERANT A,et al.Prolactin:structure,function,and regulation of secretion[J].Physiology Review,2000,80(4):1523-1631.
[18] BANKS A S,DAVIS S M,BATES S H,et al.Activation of downstream signals by the long form of the leptin receptor[J].The Journal of Biological Chemistry,2000,275:14563-14572.
[19] CHEBEL R C,SUSCA F,SANTOS J E P.Leptin genotype is associated with lactation performance and health of Holstein cows[J].Journal of Dairy Science,2008,91(7):2893-2900.

[20] MARGETIC S,GAZZOLA C,PEGG G G,et al.Leptin:a review of its peripheral actions and interactions[J].International Journal of Obesity and Related Metabolic Disorders,2002,26(11):1407-1433.

[21] SILVA L F P,ETCHEBARNE B E,WEBER MIELSEN M S,et al.Intramammary infusion of leptin decreases proliferation of mammary epithelial cells in prepubertal heifers[J].Journal of Dairy Science,2008,91(8):3034-3044.

[22] 王春艳.瘦素对奶牛乳腺上皮细胞乳蛋白合成的调控作用研究[D].硕士学位论文.呼和浩特:内蒙古农业大学,2012.
[23] NEVILLE M C,MEDINA D,MONKS J,et al.The mammary fat pad[J].Journal of Mammary Gland Biology and Neoplasia,1998,3(2):109-116.

[24] ZANGANI D,DARCY K M,SHOEMAKER S,et al.Adipocyte-epithelial interactions regulate the in vitro development of normal mammary epithelial cells[J].Experimental Cell Research,1999,247(2):399-409.

[25] HOVEY R C,MCFADDEN T B,AKERS R M.Regulation of mammary gland growth and morphogenesis by the mammary fat pad:a species comparison[J].Journal of Mammary Gland Biology and Neoplasia,1999,4(1):53-68.

[26] FEUERMANN Y,MABJEESH S J,NIV-SPECTOR L,et al.Prolactin affects leptin action in the bovine mammary gland via the mammary fat pad[J].Journal of Endocrinology,2006,191:407-413.
[27] SHILLINGFORD J M,HENNIGHAUSEN L.Experimental mouse genetics-answering fundamental questions about mammary gland biology[J].Trends in Endocrinology & Metabolism,2001,12(9):402-408.

[28] BROCKMAN J L,SCHULER L A.Prolactin signals via STAT5 and Oct-1 to the proximal cyclin D1 promoter[J].Molecular and Cellular Endocrinology,2005,239(1/2):45-53.
[29] BURGOS S A,DAI M,CANT J P.Nutrient availability and lactogenic hormones regulate mammary protein synthesis through the mammalian target of rapamycin signaling pathway[J].Journal of Dairy Science,2010,93(1):153-161.

[30] BEUGNET A,TEE A R,TAYLOR P M,et al.Regulation of targets of mTOR(mammalian target of rapamycin) signalling by intracellular amino acid availability[J].Biochemical Journal,2003,372(Pt 2):555-566.
[31] 文静.两种典型日粮模式对奶牛泌乳量、乳品质及泌乳相关激素的影响[D].硕士学位论文.长春:吉林大学,2013.
[32] 王建发.乳脂肪和乳蛋白主要前体物对DCAPCs中GH和PRL的影响及机制研究[D].博士学位论文.长春:吉林大学,2013.

Options

Outlines

模态框（Modal）标题

Abstract

Cite this article

References