| 1. |
- Pla, Indira, et al.
(författare)
-
Proteome of fluid from human ovarian small antral follicles reveals insights in folliculogenesis and oocyte maturation
- 2021
-
Ingår i: Human Reproduction. - : Oxford University Press (OUP). - 0268-1161 .- 1460-2350. ; 36:3, s. 756-770
-
Tidskriftsartikel (refereegranskat)abstract
- STUDY QUESTION: Is it possible to identify by mass spectrometry a wider range of proteins and key proteins involved in folliculogenesis and oocyte growth and development by studying follicular fluid (FF) from human small antral follicles (hSAF)?SUMMARY ANSWER: The largest number of proteins currently reported in human FF was identified in this study analysing hSAF where several proteins showed a strong relationship with follicular developmental processes.WHAT IS KNOWN ALREADY: Protein composition of human ovarian FF constitutes the microenvironment for oocyte development. Previous proteomics studies have analysed fluids from pre-ovulatory follicles, where large numbers of plasma constituents are transferred through the follicular basal membrane. This attenuates the detection of low abundant proteins, however, the basal membrane of small antral follicles is less permeable, making it possible to detect a large number of proteins, and thereby offering further insights in folliculogenesis.STUDY DESIGN, SIZE, DURATION: Proteins in FF from unstimulated hSAF (size 6.1 ± 0.4 mm) were characterised by mass spectrometry, supported by high-throughput and targeted proteomics and bioinformatics. The FF protein profiles from hSAF containing oocytes, capable or not of maturing to metaphase II of the second meiotic division during an IVM (n = 13, from 6 women), were also analysed.PARTICIPANTS/MATERIALS, SETTING, METHODS: We collected FF from hSAF of ovaries that had been surgically removed from 31 women (∼28.5 years old) undergoing unilateral ovariectomy for fertility preservation.MAIN RESULTS AND THE ROLE OF CHANCE: In total, 2461 proteins were identified, of which 1108 identified for the first time in FF. Of the identified proteins, 24 were related to follicular regulatory processes. A total of 35 and 65 proteins were down- and up-regulated, respectively, in fluid from hSAF surrounding oocytes capable of maturing (to MII). We found that changes at the protein level occur already in FF from small antral follicles related to subsequent oocyte maturation.LIMITATIONS, REASONS FOR CAUTION: A possible limitation of our study is the uncertainty of the proportion of the sampled follicles that are undergoing atresia. Although the FF samples were carefully aspirated and processed to remove possible contaminants, we cannot ensure the absence of some proteins derived from cellular lysis provoked by technical reasons.WIDER IMPLICATIONS OF THE FINDINGS: This study is, to our knowledge, the first proteomics characterisation of FF from hSAF obtained from women in their natural menstrual cycle. We demonstrated that the analysis by mass spectrometry of FF from hSAF allows the identification of a greater number of proteins compared to the results obtained from previous analyses of larger follicles. Significant differences found at the protein level in hSAF fluid could predict the ability of the enclosed oocyte to sustain meiotic resumption. If this can be confirmed in further studies, it demonstrates that the viability of the oocyte is determined early on in follicular development and this may open up new pathways for augmenting or attenuating subsequent oocyte viability in the pre-ovulatory follicle ready to undergo ovulation.STUDY FUNDING/COMPETING INTEREST(S): The authors thank the financial support from ReproUnion, which is funded by the Interreg V EU programme. No conflict of interest was reported by the authors.TRIAL REGISTRATION NUMBER: N/A.
|
|
| 2. |
- Pla, Indira, et al.
(författare)
-
Proteomic Alterations in Follicular Fluid of Human Small Antral Follicles Collected from Polycystic Ovaries—A Pilot Study
- 2022
-
Ingår i: Life. - : MDPI AG. - 0024-3019 .- 2075-1729. ; 12:3
-
Tidskriftsartikel (refereegranskat)abstract
- Polycystic ovaries (PCO) contain antral follicles that arrest growing around 3–11 mm in diameter, perturbing the dominant follicle’s selection and the subsequent ovulatory process. Proteomic alterations of PCO follicular fluid (FF) (i.e., microenvironment in which the oocyte develops until ovulation) have been studied from large follicles in connection with oocyte pickup during ovarian stimulation. The present study aimed to detect proteomic alterations in FF from unstimulated human small antral follicles (hSAF) obtained from PCO. After performing deep-sequencing label-free proteomics on 10 PCO and 10 non-PCO FF samples from unstimulated hSAF (4.6–9.8 mm), 1436 proteins were identified, of which 115 were dysregulated in PCO FF samples. Pathways and processes related to the immune system, inflammation, and oxidative stress appeared to be upregulated in PCO, while extracellular matrix receptors interactions, the collagens-containing extracellular matrix, and the regulation of signaling were downregulated. The secreted proteins SFRP1, THBS4, and C1QC significantly decreased their expression in PCO FF, and this downregulation was suggested to affect future oocyte competence. In conclusion, our study revealed, for the first time, evidence of proteomic alterations occurring in the FF of PCO hSAF that may be related to the dysfunction of follicular growth and subsequent oocyte competence.
|
|
