Association between SREBP-1 gene expression in mammary gland and milk fat yield in Sarda breed sheep

AbstractTrans-10, cis-12 conjugated linoleic acid (CLA) decreases milk fat synthesis in lactating sows and involves, at least in part, the down-regulation of lipogenic genes. The objective was to evaluate the effect of CLA on milk composition and lipogenic gene expression. Twenty multiparous sows were randomly assigned to one of the two treatments for 18 d (from day 7 to day 25 of lactation): (1) control (no CLA added) and (2) 1 % of CLA mixed into the ration. CLA treatment decreased milk fat and protein content by 20 % (P = 0·004) and 11 % (P = 0·0001), respectively. However, piglet weight did not differ between treatments (P = 0·60). Dietary CLA increased the concentration of SFA in milk fat by 16 % (P < 0·0001) and decreased MUFA by 17·6 % (P < 0·0001). In the mammary gland, CLA reduced gene expression of acetyl-CoA carboxylase-α by 37 % (P = 0·003), fatty acid synthase by 64 % (P = 0·002), stearoyl-CoA desaturase 1 by 52 % (P = 0·003), lipoprotein lipase by 26 % (P = 0·03), acyl glycerol phosphate acyltransferase 6 by 15 % (P = 0·02) and diacylglycerol acyltransferase 1 by 27 % (P = 0·02), whereas the expression of fatty acid binding protein 3 was not altered by CLA treatment (P = 0·09). Mammary expression of casein-β and α-lactalbumin was reduced by CLA by 68 % (P = 0·0004) and 62 % (P = 0·005), respectively. Additionally, CLA had no effect on the expression of lipogenic genes evaluated in adipose tissue. In summary, CLA reduced milk fat content without negatively affecting litter performance and it affected mammary expression of genes involved in all lipogenic pathways studied.

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Milk fat globule is an alternative to mammary epithelial cells for gene expression analysis in buffalo

Journal of Dairy Research ◽

10.1017/s0022029916000133 ◽

2016 ◽

Vol 83 (2) ◽

pp. 202-208 ◽

Cited By ~ 12

Author(s):

Qiuming Chen ◽

Yanjun Wu ◽

Mingyuan Zhang ◽

Wenwen Xu ◽

Xiaoping Guo ◽

...

Keyword(s):

Gene Expression ◽

Mammary Gland ◽

Epithelial Cells ◽

Expression Analysis ◽

Milk Fat ◽

Gene Expression Analysis ◽

Mammary Epithelial Cells ◽

Mammary Epithelial ◽

Milk Fat Globule ◽

Fat Globule

Owing to the difficulty in obtaining mammary gland tissue from lactating animals, it is difficult to test the expression levels of genes in mammary gland. The aim of the current study was to identify if milk fat globule (MFG) in buffalo milk was an alternative to mammary gland (MG) and milk somatic cell (MSC) for gene expression analysis. Six buffalos in late lactation were selected to collect MFG and MSC, and then MG was obtained by surgery. MFG was stained with acridine orange to successfully visualise RNA and several cytoplasmic crescents in MFG. The total RNA in MFG was successfully isolated and the integrity was assessed by agarose gel electrophoresis. We analysed the cellular components in MFG, MG and MSC through testing the expression of cell-specific genes by qRT-PCR. The results showed that adipocyte-specific gene (AdipoQ) and leucocyte-specific genes (CD43, CSF1 and IL1α) in MFG were not detected, whereas epithelial cell marker genes (Keratin 8 and Keratin 18) in MFG were higher than in MSC and lower than in MG, fibroblast marker gene (vimentin) in MFG was significantly lower than in MG and MSC, milk protein genes (LALBA, BLG and CSN2) and milk fat synthesis-related genes (ACC, BTN1A1, FABP3 and FAS) in MFG were higher than in MG and MSC. In conclusion, the total RNA in MFG mainly derives from mammary epithelial cells and can be used to study the functional gene expression of mammary epithelial cells.

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Negative effects of long-term feeding of high-grain diets to lactating goats on milk fat production and composition by regulating gene expression and DNA methylation in the mammary gland

Journal of Animal Science and Biotechnology ◽

10.1186/s40104-017-0204-2 ◽

2017 ◽

Vol 8 (1) ◽

Cited By ~ 5

Author(s):

Ping Tian ◽

Yanwen Luo ◽

Xian Li ◽

Jing Tian ◽

Shiyu Tao ◽

...

Keyword(s):

Gene Expression ◽

Dna Methylation ◽

Mammary Gland ◽

Milk Fat ◽

Negative Effects ◽

Lactating Goats

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Activation of Adipocyte mTORC1 Increases Milk Lipids in a Mouse Model of Lactation

10.1101/2021.07.01.450596 ◽

2021 ◽

Author(s):

Noura El-Habbal ◽

Allison C. Meyer ◽

Hannah Hafner ◽

JeAnna R. Redd ◽

Zach Carlson ◽

...

Keyword(s):

Gene Expression ◽

Fatty Acids ◽

Mammary Gland ◽

Milk Fat ◽

Saturated Fatty Acids ◽

Milk Composition ◽

Nutrient Sensing ◽

Lower Percentage ◽

Milk Lipids

Human milk is the recommended nutrient source for newborns. The mammary gland comprises multiple cell types including epithelial cells and adipocytes. The contributions of mammary adipocytes to breast milk composition and the intersections between mammary nutrient sensing and milk lipids are not fully understood. A major nutrient sensor in most tissues is the mechanistic target of rapamycin 1 (mTORC1). To assess the role of excess nutrient sensing on mammary gland structure, function, milk composition, and offspring weights, we used an Adiponectin-Cre driven Tsc1 knockout model of adipocyte mTORC1 hyperactivation. Our results show that the knockout dams have higher milk fat contributing to higher milk caloric density and heavier offspring weight during lactation. Additionally, milk of knockout dams displayed a lower percentage of saturated fatty acids, higher percentage of monounsaturated fatty acids, and a lower milk ω6: ω3 ratio driven by increases in Docosahexaenoic acid (DHA). Mammary gland gene expression analyses identified changes in eicosanoid metabolism, adaptive immune function and contractile gene expression. Together, these results suggest a novel role of adipocyte mTORC1 in mammary gland function and morphology, milk composition, and offspring growth.

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Effect of live weight gain before or during pregnancy on mammary gland development and subsequent milk production of Australian Holstein-Friesian heifers

Australian Journal of Experimental Agriculture ◽

10.1071/ea9870195 ◽

1987 ◽

Vol 27 (2) ◽

pp. 195 ◽

Cited By ~ 23

Author(s):

SC Valentine ◽

RC Dobos ◽

PA Lewis ◽

BD Bartsch ◽

RB Wickes

Keyword(s):

Mammary Gland ◽

Milk Fat ◽

Mammary Gland Development ◽

Live Weight ◽

Economic Implications ◽

Mating Rate ◽

Holstein Friesian ◽

The Mean ◽

Fat Yield ◽

Gland Development

Two groups of 90 Holstein-Friesian heifers were grown at 0.60 kg/day liveweight gain up to 110 kg liveweight and then grown at either 0.18, 0.62 or 0.94 kg/day for 15 weeks commencing at about 4 months of age. All heifers were then grown at 0.59 kg/day, except for a period of 15 weeks commencing at 4.5 months of pregnancy when the heifers grown at 0.62 kg/day from 110 kg liveweight were grown at either 0.22, 0.59 or 1.06 kg/day. Groups of heifers were milked or slaughtered either at mating (300 kg liveweight) or 2 weeks after calving and the chemical and histological composition of the udders determined. Mean daily yields (kg) of milk fat and solids not fat (SNF) during the first 10 weeks of the first lactation were significantly (P< 0.05) higher for heifers grown at 0.18 (0.70, 1.58) and 0.62 kg/day (0.61, 1.42) than for those grown at 0.94 kg/day (0.49, 1.19) before mating. During the complete first lactation, there was a trend for higher milk fat yield (kg) and concentration (g/kg) of heifers grown at 0.18 kg/day (122, 44) compared with those grown at 0.62 (119, 41) and 0.94 kg/day (114, 41) before mating. During the first 10 weeks of the second lactation, the mean daily yield (kg) of milk fat was significantly (P < 0.05) higher for the heifers grown at 0.18 kg/day (0.79) than for those grown at 0.62 (0.68) and 0.94 kg/day (0.74) before first mating. Rate of liveweight gain of the heifers during pregnancy had no significant effect on the production of milk or milk components. There were generally no significant differences in the composition of the udders from heifers grown at different rates of liveweight gain before mating or during pregnancy. It was concluded that, although there were no detrimental effects of rearing heifers at 0.18 kg/day before mating on production during the first lactation, the economic implications of at least a 6-month delay in commencement of lactation compared with heifers reared at a rate of liveweight gain of 0.62 kg/day must be considered.

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Inflammation Associated Gene Expression in the Mammary Gland of Lactating Mothers Who Delivered Preterm and Were Randomly Assigned to a Standard vs Increased DHA Supplement

Current Developments in Nutrition ◽

10.1093/cdn/nzab046_001 ◽

2021 ◽

Vol 5 (Supplement_2) ◽

pp. 704-704

Author(s):

Joselyn Adams ◽

Christina Valentine ◽

Lynette Rogers ◽

Rebekah Karns ◽

Masahiko Murase ◽

...

Keyword(s):

Gene Expression ◽

Mammary Gland ◽

Milk Fat ◽

Standard Dose ◽

Group Versus ◽

Milk Proteins ◽

Fold Increase ◽

Future Research ◽

Lactating Mothers ◽

Ontological Analysis

Abstract Objectives Our objective was to characterize the mRNA-seq transcriptome of the mammary gland of lactating mothers who delivered preterm and were enrolled in a randomized control trial (RCT) of standard versus increased DHA supplementation. We hypothesized that inflammation associated gene expression would be attenuated in the increased DHA group versus the standard dose group. Methods The RCT was completed by 8 participants randomized to standard of care DHA supplements (200 mg/day, STD group) and 10 randomized to increased DHA supplements (1000 mg/day, EXP group). High quality extracellular mammary epithelial cell mRNA was isolated from fresh milk fat and submitted to RNA-sequencing in n = 4 STD and n = 6 EXP DHA samples. Aligned and quantified reads were examined for differentially expressed genes using t-tests (DEG, p < 0.05 after false discovery rate adjustment). The resulting DEG list was intersected with the Broad Institute list of hallmark inflammation genes. Ontological analysis of DEGs was performed with Toppcluster. Results There were 409 DEGs overall, including 9 hallmark inflammation genes. In the EXP group, up-regulation of inflammation-inhibiting genes included NFKBIA (FC = 4.0) and IL18BP (FC = 3.6); and down-regulation of pro-inflammatory genes included IL7R (FC = −3.6) and IL1RL1 (FC = −3.9). Ontological analysis revealed 5 clusters of up-regulated gene sets in the EXP group, including immune regulation and management of oxidative stress associated clusters. Strong up-regulation was also seen in the major milk proteins LALBA (3.8-fold increase) and CSN2 (3.4-fold increase). Conclusions These findings reveal that increased DHA supplementation during lactation can modulate the expression of inflammation-associated genes within the mammary gland and support improved mammary gland function. These effects may have important clinical implications towards producing milk with a more optimal inflammasome profile and improving overall mammary gland health and function in lactating mothers who deliver preterm, with an overall benefit of reducing inflammation-driven morbidity in their premature infants. Future research with a larger RCT and greater interrogation of milk composition and volume is warranted. Funding Sources NIH, Mead Johnson Nutrition.

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