Obesity and PCOS radically alters the snRNA composition of follicular fluid extracellular vesicles

Brandon A Wyse; Reza Salehi; Stewart J Russell; Mugundhine Sangaralingam; Sahar Jahangiri; Benjamin K Tsang; Clifford L Librach

doi:10.3389/fendo.2023.1205385

Obesity and PCOS radically alters the snRNA composition of follicular fluid extracellular vesicles

Front Endocrinol (Lausanne). 2023 Jun 19:14:1205385. doi: 10.3389/fendo.2023.1205385. eCollection 2023.

Authors

Brandon A Wyse¹, Reza Salehi^{1

2

3}, Stewart J Russell¹, Mugundhine Sangaralingam¹, Sahar Jahangiri^{1

4}, Benjamin K Tsang^{2

3}, Clifford L Librach^{1

4

5

6

7}

Affiliations

¹ Research Department, CReATe Fertility Centre, Toronto, ON, Canada.
² Chronic Disease Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada.
³ Departments of Obstetrics and Gynecology & Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada.
⁴ CReATe Biobank, Toronto, ON, Canada.
⁵ Department of Obstetrics and Gynecology, University of Toronto, Toronto, ON, Canada.
⁶ Department of Physiology, University of Toronto, Toronto, ON, Canada.
⁷ Biological Sciences, DAN Women & Babies Research Program, Sunnybrook Research Institute, Toronto, ON, Canada.

Abstract

Introduction: The ovarian follicle consists of the oocyte, somatic cells, and follicular fluid (FF). Proper signalling between these compartments is required for optimal folliculogenesis. The association between polycystic ovarian syndrome (PCOS) and extracellular vesicular small non-coding RNAs (snRNAs) signatures in follicular fluid (FF) and how this relates to adiposity is unknown. The purpose of this study was to determine whether FF extracellular vesicle (FFEV)-derived snRNAs are differentially expressed (DE) between PCOS and non-PCOS subjects; and if these differences are vesicle-specific and/or adiposity-dependent.

Methods: FF and granulosa cells (GC) were collected from 35 patients matched by demographic and stimulation parameters. FFEVs were isolated and snRNA libraries were constructed, sequenced, and analyzed.

Results: miRNAs were the most abundant biotype present, with specific enrichment in exosomes (EX), whereas in GCs long non-coding RNAs were the most abundant biotype. In obese PCOS vs. lean PCOS, pathway analysis revealed target genes involved in cell survival and apoptosis, leukocyte differentiation and migration, JAK/STAT, and MAPK signalling. In obese PCOS FFEVs were selectively enriched (FFEVs vs. GCs) for miRNAs targeting p53 signalling, cell survival and apoptosis, FOXO, Hippo, TNF, and MAPK signalling.

Discussion: We provide comprehensive profiling of snRNAs in FFEVs and GCs of PCOS and non-PCOS patients, highlighting the effect of adiposity on these findings. We hypothesize that the selective packaging and release of miRNAs specifically targeting anti-apoptotic genes into the FF may be an attempt by the follicle to reduce the apoptotic pressure of the GCs and stave off premature apoptosis of the follicle observed in PCOS.

Keywords: PCOS (polycystic ovarian syndrome); exosome (vesicle); extracellular vesicles (EVs); miRNA; obesity; smallRNA; smallRNASeq.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Extracellular Vesicles* / metabolism
Female
Follicular Fluid / metabolism
Humans
MicroRNAs* / genetics
MicroRNAs* / metabolism
Obesity / metabolism
Polycystic Ovary Syndrome* / genetics
Polycystic Ovary Syndrome* / metabolism

Substances

MicroRNAs

Grants and funding

A seed grant was provided by the Canadian Fertility and Andrology Society (2017). Postdoctoral fellowships were awarded to RS by the Lalor Foundation and Mathematics of Information Technology and Complex Systems (Mitacs); All other funding was provided by CReATe Fertility Centre through the reinvestment of clinical earnings.