The regulation of glucose on milk fat synthesis is mediated by the ubiquitin-proteasome system in bovine mammary epithelial cells.
Biochem Biophys Res Commun
; 465(1): 59-63, 2015 Sep 11.
Article
em En
| MEDLINE
| ID: mdl-26231798
ABSTRACT
Glucose as one of the nutrition factors plays a vital role in the regulation of milk fat synthesis. Ubiquitin-proteasome system (UPS) is a vital proteolytic pathway in all eukaryotic cells through timely marking, recognizing and degrading the poly-ubiquitinated protein substrates. Previous studies indicated that UPS plays a considerable role in controlling the triglyceride (TG) synthesis. Therefore, the aim of this study is to confirm the link between high-glucose and UPS and its regulation mechanism on milk fat synthesis in BMEC (bovine mammary epithelial cells). We incubated BMEC with normal (17.5 mm/L) and high-glucose (25 mm/L) with and without proteasome inhibitor epoxomicin and found that, compared with the control (normal glucose and without proteasome inhibitor), both high-glucose concentration and proteasome inhibitor epoxomicin could increase the accumulation of TG and poly-ubiquitinated proteins, and reduce significantly three proteasome activities (chymotrypsin-like, caspase-like, and trypsin-like). In addition, high-glucose concentration combined with proteasome inhibitor further enhanced the increase of the poly-ubiquitinated protein level and the decrease of proteasome activities. Our results suggest that the regulation of high-glucose on milk fat synthesis is mediated by UPS in BMEC, and high-glucose exposure could lead to a hypersensitization of BMEC to UPS inhibition which in turn results in increased milk fat synthesis.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Triglicerídeos
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Ubiquitina
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Complexo de Endopeptidases do Proteassoma
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Células Epiteliais
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Glucose
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Glândulas Mamárias Animais
Limite:
Animals
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article