Glucose transporter 1 expression accompanies hypoxia sensing in the cyclic canine corpus luteum

Author(s)

Papa, Paula de Carvalho ^[1] ; Medeiros de Carvalho Sousa, Liza Margareth ^[1] ; Silva, Renata dos Santos ^[1] ; de Fatima, Luciana Alves ^[1] ; da Fonseca, Vanessa Uemura ^[1] ; do Amaral, Vanessa Coutinho ^[1] ; Hoffmann, Bernd ^[2] ; Alves-Wagner, Ana Barbara ^[3] ; Machado, Ubiratan Fabres ^[3] ; Kowalewski, Mariusz Pawel ^[4]

Affiliation

^[1] Univ Sao Paulo, Fac Vet Med & Anim Sci, Dept Surg, Sect Anat, BR-05508270 Sao Paulo - Brazil

^[2] Univ Giessen, Clin Obstet Gynecol & Androl Large & Small Anim, D-35390 Giessen - Germany

^[3] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, BR-05508270 Sao Paulo - Brazil

^[4] Univ Zurich, Inst Vet Anat, Zurich - Switzerland

• Document type: Journal article
• Source: Reproduction; v. 147, n. 1, p. 81-89, JAN 2014.
• Web of Science Citations: 7

Abstract

The canine corpus luteum (CL) functions as a source of progesterone (P-4) and 17 beta-oestradiol (E-2); however, the transport of energy substrates to maintain its high hormonal output has not yet been characterised. This study involved the localisation and temporal distribution of the facilitative glucose transporter 1 and the quantification of the corresponding protein (GLUT1) and gene (SLC2A1) expression. Some GLUT1/SLC2A1 regulatory proteins, such as hypoxia-inducible factor 1 alpha (HIF1A) and fibroblast growth factor 2 (FGF2); mRNAs, such as HIF1A, FGF2 and vascular endothelial growth factor A (VEGFA); and VEGFA receptors 1 and 2 (FLT1 and KDR) were also analysed from days 10 to 70 after ovulation. Additionally, plasma P-4 and E-2 levels were assessed via chemiluminescence. Moreover, the canine KDR sequence has been cloned, thereby enabling subsequent semi-quantitative PCR analysis. Our results demonstrate time-dependent variations in the expression profile of SLC2A1 during dioestrus, which were accompanied by highly correlated changes (0.84<r<0.98; P<0.03) in the gene expression of HIF1A, VEGF and FLT1 as well as in P-4 plasma concentrations. FGF2 mRNA correlated with E-2 plasma concentrations (r=0.61; P=0.01). Our data reveal that the glucose transporter is regulated throughout the CL lifespan and suggest that CL depends on the sensing of hypoxia and the status of luteal vascularisation. Moreover, time-dependent expression of GLUT1/SLC2A1 may lie underneath increased metabolic and energetic requirements for sustaining P-4 production. (AU)

• FAPESP's process: 10/07373-9 - Corpus luteum and diestrus in the bitch: a study model for hormonal-dependent metabolic alterations
• Grantee: Paula de Carvalho Papa Keohane
• Support Opportunities: Scholarships abroad - Research
• FAPESP's process: 11/17768-3 - 17b-estradiol role on the luteolytic process in non-pregnant dogs
• Grantee: Paula de Carvalho Papa Keohane
• Support Opportunities: Regular Research Grants