Measurement of redox potential and steroid concentrations in the follicular fluid of growing and regressing follicles of mares.

This study investigates if oxidation-reduction levels in the follicular fluid of horse follicles can be a new indicator of follicular health and if there is a significant correlation with hormonal parameters and growth stages. However, the data suggests that oxidation-reduction parameters do not correlate well with the stage of follicular growth or regression as detected by ultrasound monitoring or hormone concentration assessment.

Research Methodology

• The researchers classified the follicles as either growing or regressing using ultrasound technology.
• A total of 48 follicles with diameters ranging from 20 to 56 mm were aspirated using transvaginal ultrasound-guided follicular aspiration.
• The researchers then examined the follicular concentration of oestradiol and progesterone in relation to the diameter of growing follicles.
• The oxidation-reduction (redox) potential index D2 was also calculated which ranged from -448 to +431 in the collected fluids.

Findings of the Study

• The correlation between the follicular concentration of oestradiol and progesterone and the diameter of growing follicles was found to be r = 0.64 and r = 0.57, respectively.
• When the researchers used both the endocrinological and ultrasonographic parameters and the analysis of oxidation and reduction levels to evaluate the follicles, the agreement between these methods was found to be 72.5%.
• However, these results suggest that redox reactions’ parameters do not correlate closely with the stage of follicular growth or regression as established through in vivo scanning of ovaries or by assessing follicular steroid concentrations.

Significance and Implications of the Research

• Despite the lack of a close correlation, the researchers suggest that the measurement of redox potentials could provide an opportunity to examine the total metabolic process in follicular cells and foresee impairments in cellular performances.
• Changes in redox parameters in growing follicles could aid in predicting their future development earlier.
• The data demonstrates that growing and regressing follicles do not represent nonatretic, early atretic and atretic follicles, respectively.