The canine corpus luteum (CL) functions as a source of progesterone (P4) and 17β-oestradiol (E2); 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 1α (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 P4 and E2 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 P4 plasma concentrations. FGF2 mRNA correlated with E2 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 P4 production.
Paula de Carvalho Papa, Liza Margareth Medeiros de Carvalho Sousa, Renata dos Santos Silva, Luciana Alves de Fátima, Vanessa Uemura da Fonseca, Vanessa Coutinho do Amaral, Bernd Hoffmann, Ana Bárbara Alves-Wagner, Ubiratan Fabres Machado and Mariusz Pawel Kowalewski
Vanessa Machado, Joana Lopes, Mariana Patrão, João Botelho, Luís Proença and José João Mendes
Hormones and inflammatory mechanisms are implicated with female reproductive function, including follicle maturation, ovulation, embryo implantation, and pregnancy. Periodontitis is a chronic inflammatory disease due to a polymicrobial disruption of the homeostasis and may be considered as a potential risk factor that affect female fertility. The role of periodontitis is becoming meaningful, with significant associations with polycystic ovary syndrome, endometriosis and bacterial vaginosis. Further, periodontitis is linked with known risk factors towards female infertility, such as age, obesity, and chronic kidney disease. This review aims to summarize the available evidence on the association between periodontitis and female infertility-associated conditions, and to discuss warranting steps in future research.