Genome wide effects of oleic acid on cultured bovine granulosa cells: evidence for the activation of pathways favoring folliculo-luteal transition

Abstract Background Metabolic stress, as negative energy balance on one hand or obesity on the other hand can lead to increased levels of free fatty acids in the plasma and follicular fluid of animals and humans. In an earlier study, we showed that increased oleic acid (OA) concentrations affected the function of cultured bovine granulosa cells (GCs). Here, we focus on genome wide effects of increased OA concentrations. Results Our data showed that 413 genes were affected, of which 197 were down- and 216 up-regulated. Specifically, the expression of FSH-regulated functional key genes, CCND2, LHCGR, INHA and CYP19A1 and 17-β-estradiol (E2) production were reduced by OA treatment, whereas the expression of the fatty acid transporter CD36 was increased and the morphology of the cells was changed due to lipid droplet accumulation. Bioinformatic analysis revealed that associated pathways of the putative upstream regulators “FSH” and “Cg (choriogonadotropin)” were inhibited and activated, respectively. Down-regulated genes are over-represented in GO terms “reproductive structure/system development”, “ovulation cycle process”, and “(positive) regulation of gonadotropin secretion”, whereas up-regulated genes are involved in “circulatory system development”, “vasculature development”, “angiogenesis” or “extracellular matrix/structure organization”. Conclusions From these data we conclude that besides inhibiting GC functionality, increased OA levels seemingly promote angiogenesis and tissue remodelling, thus suggestively initiating a premature fulliculo-luteal transition. In vivo this may lead to impeded folliculogenesis and ovulation, and cause sub-fertility.

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circLMTK2 acts as a sponge of miR-150-5p and promotes proliferation and metastasis in gastric cancer

Molecular Cancer ◽

10.1186/s12943-019-1081-4 ◽

2019 ◽

Vol 18 (1) ◽

Cited By ~ 15

Author(s):

Sen Wang ◽

Dong Tang ◽

Wei Wang ◽

Yining Yang ◽

Xiaoqing Wu ◽

...

Keyword(s):

Gastric Cancer ◽

Bioinformatic Analysis ◽

Migration And Invasion ◽

Circular Rnas ◽

Normal Tissues ◽

Tumour Metastasis ◽

Genome Wide ◽

Proliferation And Metastasis

Abstract Background As a novel class of non-coding RNAs, circular RNAs (circRNAs) are key regulators of the development and progression of different cancers. However, little is known about the function and biological mechanism of circLMTK2, also named hsa_circ_0001725, in gastric cancer (GC) tumourigenesis. Methods circLMTK2 was identified in ten paired cancer specimens and adjacent normal tissues by RNA sequencing and genome-wide bioinformatic analysis and verified by quantitative real-time PCR (qRT-PCR). Knockdown or exogenous expression of circLMTK2 combined with in vitro and in vivo assays were performed to prove the functional significance of circLMTK2. The molecular mechanism of circLMTK2 was demonstrated by searching the CircNet database and confirmed by RNA in vivo precipitation assays, western blotting, luciferase assays and rescue experiments. Results circLMTK2 was frequently upregulated in GC tissues, and high circLMTK2 expression was associated with poor prognosis, lymph node metastasis and poor TNM stage in GC patients. Functionally, circLMTK2 overexpression promoted GC cell proliferation and tumourigenicity in vitro and in vivo. Furthermore, ectopic circLMTK2 expression enhanced GC cell migration and invasion in vitro and tumour metastasis in vivo. In addition, we demonstrated that circLMTK2 could sponge miR-150-5p, thus indirectly regulating the c-Myc expression and contributing to GC tumourigenesis. Conclusion Our findings demonstrate that circLMTK2 functions as a tumour promoter in GC through the miR-150-5p/c-Myc axis and could thus be a prognostic predictor and therapeutic target for GC.

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Identification of miRNAs associated with the follicular–luteal transition in the ruminant ovary

Reproduction ◽

10.1530/rep-12-0025 ◽

2012 ◽

Vol 144 (2) ◽

pp. 221-233 ◽

Cited By ~ 118

Author(s):

D McBride ◽

W Carré ◽

S D Sontakke ◽

C O Hogg ◽

A Law ◽

...

Keyword(s):

Granulosa Cells ◽

Expression Profiles ◽

Oestrous Cycle ◽

Corpora Lutea ◽

Follicular Cells ◽

Mirna Targets ◽

Genome Wide ◽

Ovulatory Follicles

Little is known about the involvement of microRNAs (miRNAs) in the follicular–luteal transition. The aim of this study was to identify genome-wide changes in miRNAs associated with follicular differentiation in sheep. miRNA libraries were produced from samples collected at defined stages of the ovine oestrous cycle and representing healthy growing follicles, (diameter, 4.0–5.5 mm), pre-ovulatory follicles (6.0–7.0 mm), early corpora lutea (day 3 post-oestrus) and late corpora lutea (day 9). A total of 189 miRNAs reported in sheep or other species and an additional 23 novel miRNAs were identified by sequencing these libraries. miR-21, miR-125b, let-7a and let-7b were the most abundant miRNAs overall, accounting for 40% of all miRNAs sequenced. Examination of changes in cloning frequencies across development identified nine different miRNAs whose expression decreased in association with the follicular–luteal transition and eight miRNAs whose expression increased during this transition. Expression profiles were confirmed by northern analyses, and experimentally validated targets were identified using miRTarBase. A majority of the 29 targets identified represented genes known to be actively involved in regulating follicular differentiation in vivo. Finally, luteinisation of follicular cells in vitro resulted in changes in miRNA levels that were consistent with those identified in vivo, and these changes were temporally associated with changes in the levels of putative miRNA targets in granulosa cells. In conclusion, this is the first study to characterise genome-wide miRNA profiles during different stages of follicle and luteal development. Our data identify a subset of miRNAs that are potentially important regulators of the follicular–luteal transition.

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Thrombospondin-1 Expression Is Increased during Follicular Atresia in the Primate Ovary

Endocrinology ◽

10.1210/en.2007-0835 ◽

2007 ◽

Vol 149 (1) ◽

pp. 185-192 ◽

Cited By ~ 25

Author(s):

Fiona H. Thomas ◽

Helen Wilson ◽

Audrey Silvestri ◽

Hamish M. Fraser

Keyword(s):

Endothelial Cells ◽

Granulosa Cells ◽

Follicular Phase ◽

Follicular Atresia ◽

Gonadotropin Secretion ◽

Antral Follicles ◽

Cd36 Expression ◽

Mrna And Protein Expression ◽

Vegf Trap

Thrombospondin (TSP)-1 is an antiangiogenic extracellular matrix glycoprotein that modulates several aspects of cellular function. The aim of this study was to determine the pattern of TSP-1 mRNA and protein expression as well as expression of its receptor CD36 in the marmoset ovary and to investigate the effects of inhibition of gonadotropins or VEGF activity on TSP-1 and CD36 expression in vivo. GnRH antagonist or VEGF Trap, a soluble decoy receptor, was administered on d 0 of the follicular phase of the cycle, and ovaries were collected at the end of the follicular phase (d 10). TSP-1 mRNA and protein were present in granulosa cells of preantral and antral follicles, with the highest staining at the late secondary and tertiary stages. Moreover, expression of TSP-1 mRNA and protein was significantly increased in tertiary follicles undergoing atresia. CD36 protein was detected in granulosa cells of preantral and antral follicles as well as in endothelial cells of large vessels. Inhibition of gonadotropin secretion or VEGF activity had no effect on TSP-1 expression; however, expression of CD36 protein was inhibited by the VEGF Trap. In conclusion, TSP-1 may be involved in the cessation of angiogenesis in follicles undergoing atresia; alternatively, TSP-1 may act on granulosa and/or endothelial cells to promote follicular atresia in the ovary. Angiogenesis is likely to involve a balance between pro- and antiangiogenic factors. Our results suggest that loss of VEGF activity does not regulate TSP-1 expression directly but may influence TSP-1 activity via down-regulation of the CD36 receptor.

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