Histological analysis of (antral) follicle density in ovarian cortex tissue attached to stripped endometriomas

PURPOSE

When resecting endometriomas with the stripping technique, in the majority of cases, a thin line of adjacent ovarian cortex is attached to the endometrioma. In this study, we performed histological analysis to determine (antral) follicle density in the ovarian cortex tissue attached to stripped endometriomas and assessed patient- and surgical characteristics that could affect this.

METHODS

Histological slides of previously removed endometriomas were assessed. Follicles in the attached ovarian tissue were classified according to maturation, and follicular density was determined. Immunofluorescent staining of antral follicles in a subset of endometriomas was also performed.

RESULTS

In 90 out of 96 included endometriomas (93.7%), ovarian tissue attached to the cyst wall was observed. One thousand nine hundred forty-four follicles at different maturation stages were identified (3 follicles/mm3). Follicle density was negatively associated with age (p < 0.001). Antral follicles (< 7-mm diameter) were present in the ovarian tissue attached to 35 endometriomas (36.5%) derived from younger patients compared to endometriomas where none were detected (30 versus 35 years, p = 0.003). Antral follicle density was 1 follicle/mm3. Based on immunofluorescence, healthy antral follicles were identified in two out of four examined endometriomas.

CONCLUSIONS

Ovarian tissue attached to stripped endometriomas holds potential as a non-invasive source for antral follicles. In theory, application of IVM could be an interesting alternative FP option in young patients with endometriomas who undergo cystectomy in order to transform the surgical collateral damage to a potential oocyte source. Our results encourage future research with fresh tissue to further assess the quality and potential of these follicles.

TRIAL REGISTRATION

Clinical Trials.gov Identifier: B21.055 (METC LDD), date of registration 12-08-2021, retrospectively registered.

Two mutations at KRT74 and EDAR synergistically drive the fine-wool production in Chinese sheep

INTRODUCTION

Fine-wool sheep are the most common breed used by the wool industry worldwide. Fine-wool sheep have over a three-fold higher follicle density and a 50% smaller fiber diameter than coarse-wool sheep.

OBJECTIVES

This study aims to clarify the underlying genetic basis for the denser and finer wool phenotype in fine-wool breeds.

METHOD

Whole-genome sequences of 140 samples, Ovine HD630K SNP array data of 385 samples, including fine, semi-fine, and coarse wool sheep, as well as skin transcriptomes of nine samples were integrated for genomic selection signature analysis.

RESULTS

Two loci at keratin 74 (KRT74) and ectodysplasin receptor (EDAR) were revealed. Fine-scale analysis in 250 fine/semi-fine and 198 coarse wool sheep narrowed this association to one C/A missense variant of KRT74 (OAR3:133,486,008, P = 1.02E-67) and one T/C SNP in the regulatory region upstream of EDAR (OAR3:61,927,840, P = 2.50E-43). Cellular over-expression and ovine skin section staining assays confirmed that C-KRT74 activated the KRT74 protein and specifically enlarged cell size at the Huxley's layer of the inner root sheath (P < 0.01). This structure enhancement shapes the growing hair shaft into the finer wool than the wild type. Luciferase assays validated that the C-to-T mutation upregulated EDAR mRNA expression via a newly created SOX2 binding site and potentially led to the formation of more hair placodes.

CONCLUSIONS

Two functional mutations driving finer and denser wool production were characterized and offered new targets for genetic breeding during wool sheep selection. This study not only provides a theoretical basis for future selection of fine wool sheep breeds but also contributes to improving the value of wool commodities.

Abnormalities of early folliculogenesis and serum anti-Müllerian hormone in chinese patients with polycystic ovary syndrome

Purpose

To investigate abnormalities of early folliculogenesis and Anti-Müllerian hormone (AMH) concentrations in polycystic ovary syndrome (PCOS) patients, and to analyze the association between AMH and early-stage follicle densities (FD).

Methods

A total of 175 patients underwent ovarian tissue cryopreservation in the first official cryobank in China, of which 16 patients aged 30–40 years old were diagnosed with endometrial cancer (all without initial chemo/radiotherapy), including 5 patients with concurrent PCOS and the other 11 patients without. We obtained standard cortical biopsies to measure FD using calcein staining. Blood samples were collected before cryopreservation to evaluate AMH concentrations.

Results

PCOS showed nearly three times the primordial and primary FD than NPCOS (P = 0.027), as well as more secondary preantral follicles (P = 0.002). A significantly higher proportion of secondary preantral follicles and a lower proportion of primordial and primary follicles were observed in PCOS (P = 0.01). Furthermore, the AMH concentration in PCOS was four times higher than that in NPCOS (P = 0.003), which is significantly correlated with primordial and primary follicle densities (r = 0.855, P < 0.001) and secondary preantral follicle densities (r = 0.732, P = 0.007).

Conclusions

We found significant disorders of early folliculogenesis in PCOS, which showed close correlation with increased AMH concentrations. To our knowledge, abnormalities of early-stage follicles have been shown for the first time in ovarian tissue of Chinese PCOS women. We suppose that the elevated AMH level is associated with abnormalities of early folliculogenesis within the complex PCOS pathogenesis, which may explain why AMH has the potential to be used as a biomarker for the diagnosis of PCOS. Our findings provide more implications for understanding the mechanism of PCOS, and new directions for further studies.

Serum anti-Mullerian hormone (AMH) concentration has limited prognostic value for density of primordial and primary follicles, questioning it as an accurate parameter for the ovarian reserve

OBJECTIVES

To evaluate the prognostic value of anti-Mullerian hormone (AMH) levels in estimating the ovarian density of primordial and primary follicles, which can be assumed to reflect the real ovarian reserve.

STUDY DESIGN

A total of 537 women, average age 30.4 years (range 8.0-43.7 years), underwent ovarian tissue cryopreservation prior to gonadotoxic therapies due to malignant diseases which do not affect ovarian reserve parameters. Standardized ovarian biopsies were obtained, and follicular density was analysed. The prognostic accuracy of serum AMH in estimating ovarian follicle density was evaluated.

MAIN OUTCOME MEASURES

Histologically determined follicle density, AMH serum concentration and their correlation.

RESULTS

In children, follicle density was high but AMH concentration was low. AMH concentration was predicted to be maximum at the age of 15.5 years. In women aged over 15.5 years, the relationship between AMH concentration and follicle density was evaluated. Crude analysis revealed that serum AMH levels and follicular density were moderately correlated (r = 0.34, p < 0.001). From the adjusted regression model the predicted value of follicle density of women aged 20, 30 and 40 years as well as the associated 50 % and 95 % prediction intervals (50 % PI and 95 % PI, respectively) were calculated. For example, for women aged 40 years with a serum AMH level of 1 ng/ml, a follicle density of 2.3/mm³ (50 %PI: [1.1, 4.6]; 95 %PI: [0.3, 18]) was predicted. These large prediction intervals demonstrate the low predictive value of serum AMH for the ovarian follicle density.

CONCLUSIONS

Serum AMH levels have limited prognostic value for the follicle density and therefore for the real ovarian reserve.

Ovarian cortical follicle density in infertile women with low anti-Müllerian hormone

PURPOSE

To evaluate the association between anti-Müllerian hormone (AMH) and follicle density in infertile women with diminished ovarian reserve (DOR) versus women with normal ovarian reserve?

METHODS

Case-control study comparing follicle densities in ovarian cortex from 20 infertile women with DOR (AMH ≤ 5 pmol/L) and 100 controls with presumed normal ovarian reserve.

RESULTS

For all women > 25 years, the follicle densities correlated positively with AMH levels. For each single picomole per liter increase in AMH the follicle density increased by 6% (95% CI 3.3-8.5%) when adjusted for age. This was similar for women with DOR and controls. The follicle density was 1.8 follicles/mm³ cortical tissue in women with DOR versus 7.0 in age-paired controls (p = 0.04). The women with DOR had a median AMH of 1.8 pmol/L versus 14.4 pmol/L in the age-paired control group (p < 0.001). The ratio of AMH/follicle density was 1:1 (1.8/1.8) in women with DOR and 2:1 (14.4/7.0) in the age-paired controls. Analyses for gonadotropin receptor polymorphisms could not explain the characteristics of women with DOR. The proportion of secondary follicles was higher in women with DOR compared with controls (4.6% versus 1.4%, p = 0.0003). Pooling all patients, the follicle density decreased significantly by 7.7% for every year added (p < 0.0001). The women with DOR had lower follicle densities than the controls, but the slopes were equal in the two cohorts.

CONCLUSIONS

Follicle density and AMH concentrations correlate also when AMH is low. However, AMH is only a reliable marker for the true ovarian reserve when age is included in the estimation and women with DOR may have more follicles than their AMH levels imply.