FSH supplementation to culture medium is beneficial for activation and survival of preantral follicles enclosed in equine ovarian tissue.

This research investigates how adding FSH (Follicle-stimulating hormone) impacts the in-vitro culture (IVC) of preantral follicles in horse ovarian tissues. The study found that adding around 50 ng/mL FSH provides the most favourable conditions for follicle survival and development, and stable production of estradiol and ROS (reactive oxygen species).

Study Design and Methodology

• The study is focused on understanding the influence of different concentrations of bovine recombinant follicle-stimulating hormone (FSH) on the in vitro culture of preantral follicles sourced from equine ovarian tissue fragments.
• The researchers used random ovarian fragments and subjected them to experimental conditions. They were either fixed immediately as a fresh non-cultured control or subjected to culture for 1 or 7 days in a media blend of α-MEM(+) supplemented with different concentrations of FSH: 0, 10, 50, and 100 ng/mL.
• This was followed by a thorough analysis using classical histology to understand the impacts in detail.

Results of the Research

• A notable result is that the 50-ng/mL FSH treatment led to the highest percentage of morphologically normal follicles – superior to all other groups. This was observed after Day 1 and Day 7 of culture.
• The same FSH concentration also yielded the highest percentage of developing follicles (transition, primary, and secondary), and led to increased follicular and oocyte diameters after Day 7 of culture.
• The experimental setup also revealed that associated estradiol secretion and ROS production were sustained in the cases where 50-ng/mL FSH was added to the system. The study monitored steroidal secretion and ROS production at day 1 and 7, providing insights into the ongoing biochemical processes.

Conclusion of the Study

• The researchers concluded that the addition of 50 ng/mL of FSH to the culture promoted the activation of primordial follicles to developing follicles, improved survival rates of preantral follicles and ensured the stable production of both estradiol and reactive oxygen species (ROS) in horse ovarian tissue after 7 days of culture.
• This finding has potential implications in the development of more effective in-vitro fertilization techniques and can guide similar future research as it suggests a key factor influencing equine follicular development.