Establishment of an Experimental Mouse Model of Endometrioma to Study its Related Infertility

Summary

This study introduces a novel mouse model specifically designed to simulate endometrioma, a clinically significant subtype of endometriosis. By utilizing C57BL/6J mice, the model aims to elucidate the pathophysiological mechanisms underlying endometrioma-related infertility, offering a refined tool to bridge the current knowledge gap in reproductive medicine.

Abstract

Endometrioma (OMA), a subtype of endometriosis characterized by the formation of endometriotic cysts in the ovaries, affects 17-44% of individuals diagnosed with endometriosis. Women with OMA often experience compromised fertility, yet the exact mechanisms underlying OMA-associated infertility remain unclear. Notably, existing animal models simulate superficial peritoneal endometriosis (SUP) and deep infiltrating endometriosis (DIE), leaving a notable gap in research focused on OMA. In response to the gap of knowledge, this paper introduces a pioneering OMA-simulating mouse model and provides a comprehensive description of the techniques and procedures employed in the model. With a high success rate of 83% and ovarian lesion specificity, this model holds significant promise for advancing our understanding of OMA, particularly in the context of infertility. It offers a valuable platform for conducting targeted research into OMA-associated fertility challenges, potentially paving the way for improved diagnostic and therapeutic strategies in the field of reproductive medicine.

Introduction

Endometrioma (OMA) is the most predominant subtype of endometriosis, observed in approximately 17-44% of individuals diagnosed with endometriosis^1,2. It is characterized by the formation of endometriotic cysts within the ovaries. These cysts, colloquially termed "chocolate cysts", derive their name from their distinctive brown, tar-like consistency³. In addition to OMA, endometriosis can also present as superficial peritoneal endometriosis (SUP) and deep infiltrating endometriosis (DIE). SUP refers to the lesions on the peritoneal lining, whereas DIE refers to lesions penetratin....

Protocol

All experimental procedures conducted in this study were approved and regulated under protocol number 21-203-MIS_[C] by the Ethical Committee of the Chinese University of Hong Kong.

1. Animal acclimatization and selection

1. Mice preparation
   1. Obtain 18 C57BL/6J mice (primiparous females, 8-9 weeks old: 6 donors, 12 recipients) from a reputable supplier. Verify the health certificates.
   2. Maintain all mice in a controlled housing environment: 22-24 &.......

Discussion

The prevalence of OMA in the global female population underscores a critical health concern³⁸. Beyond the general symptoms of endometriosis, OMA brings additional challenges for fertility, including severe pelvic pain, potential for ovarian torsion, and other notable implications^39,40. While the understanding of OMA pathogenesis and progression is largely shrouded in mystery, the knowledge vacuum not only impedes the formulation of targete.......

Materials

Name	Company	Catalog Number	Comments
1 cc syringe with 25 G needle	BD Biosciences	301320
10 mm Tissue culture dish	FALCON	353001
10% Buffered formalin	Fisher Scientific	SF100-4
10x phosphate buffered saline (PBS) buffer	Fisher Scientific	AM9625
30 G needle	BD Biosciences	305107
5-0 black braided silk non-absorbable suture	Ethicon Inc.	W500H
70% Ethanol
Adhesive microscope slides	Marienfeld	810401
Buprenorphine Injection	Med-Vet International	RXBUPRENOR5
Double-headed cotton swab	SANYO Co., LTD.	HUBY-340
Fine forceps	Fine Science Tools	11254-20
Ketamine	Alfasan International b.v	2203095-08
Microtubes	Corning	MCT-150-C
Needle holder	Excelta Corporation	2827-NH-35-SE-ND
Ophthalmic ointment	Major Pharmaceuticals	10033691
Periodic Acid Schiff (PAS) Stain Kit	Abcam	Ab150680
Powder free sterile gloves	Fisher Scientific	19020558
Processing/embedding cassettes	Fisher Scientific	15-197-700A
Size 3 scalpel	Fisher Scientific	22-079-657
Small serrated semi-curved forceps	Roboz Surgical Instruments Co.	RS-5135
Small surgical scissors	Roboz Surgical Instruments Co.	RS-5850
Standard light microscope			For evaluating vaginal cytology smears and histological analysis.
Steel scalpel blades #10	B.Braun	BB510
Sterile gauze	MEDICOM	HMWS 077
Sterilized pyrex glass Petri dishes	Corning	70160-101
Thermoregulated electric pad
VICRYL RAPIDE (polyglactin 910) absorbable Suture	Ethicon Inc.	W9918
Xylazine	Alfasan International b.v	2110333-10