Naturally occurring androgen excess cows are present in dairy and beef herds and have similar characteristics to women with PCOS

Abstract

Beef cows with excess androstenedione (A4; High A4) in follicular fluid (FF) and secreted by the ovarian cortex have been reported from the University of Nebraska-Lincoln physiology herd displaying characteristics reminiscent of polycystic ovary syndrome (PCOS). Thus, we hypothesized that naturally occurring High A4 cows were present in other dairy and beef herds. Fourteen Jordan (Amman, Jordon) dairy heifers and 16 U.S. Meat Animal Research Center beef heifers were classified by FF (High A4: A4 > 40 ng/mL and Control: A4 < 20 ng/mL) and/or cortex culture media (High A4 > 1 ng/mL/d or Control < 1 ng/mL/d). High A4 dairy heifers (n = 6) had greater A4 concentrations (7.6-fold) in FF and (98-fold) greater in ovarian cortex culture media with greater numbers of primordial and fewer later-stage follicles than Controls (n = 8) even after 7 d of culture. Also, the ovarian cortex had greater staining for Picro Sirius red in High A4 dairy heifers compared with Controls indicating increased fibrosis. Thecal cells from High A4 dairy heifers had greater STAR, LHCGR, CYP17A, CD68, and PECAM mRNA expression with increased mRNA abundance of CYP17A1 and CD68 in the ovarian cortex cultures compared with Control dairy heifers. Similarly, cortex culture media from High A4 beef heifers (n = 10) had increased A4 (290-fold; P ≤ 0.001), testosterone (1,427-fold; P ≤ 0.001), and progesterone (9-fold; P ≤ 0.01) compared with Control heifers with increased primordial follicles and decreased later-stage follicles even after 7 d of culture, indicating abnormal follicular development. High A4 ovarian cortex cultures from beef heifers also had increased fibrosis markers and greater expression of PECAM (P = 0.01) with a tendency for increased vascular endothelial cadherin compared with Controls (n = 6). These two trials support our hypothesis that naturally occurring androgen excess cows are present in other dairy and beef herds. The ability to identify these females that have excess A4 ovarian microenvironments may allow for their use in understanding factors causing abnormal follicle development linked to androgen excess and inflammation.

Keywords: androstenedione; fibrosis; follicle stages; inflammation; ovarian cortex cultures; polycystic ovary syndrome.

Figure 1.

Dominant follicle steroid hormone concentrations (A–C) compared between Control and High A4 animals. (A) Androstenedione (A4), (B) progesterone (P4), (C) estradiol (E2) and (D) daily A4 concentrations, and (E) overall A4 concentrations in ovarian cortex cultures from High A4 and Control dairy heifers. Abbreviation: High A4, high androstenedione.

Figure 2.

Average numbers of follicles in trial 1 at different follicle stages (A) before culture and (B) after 7 d of culture. Collagen staining (Pico Sirus Red [PSR]—an indicator of fibrosis) for (C) Control and (D) High A4 dairy heifer ovarian cortex cultures. (E) Graph comparing the average area of PSR-positive staining per ovarian cortex field (pixels/μm²) between High and Control dairy heifers. Abbreviation: High A4, high androstenedione.

Figure 3.

Quantitative real-time polymerase chain reaction results for StAR (A), LHCGR (B), CYP17A1 (C), CD68 (D), PECAM (E), KDR (F), NRP-1 (G), and VE-cadherin (H) in theca cells collected from dominant follicles of Control (white bars, n = 8) and High A4 (black bars, n = 6) dairy heifers. The geometric mean of GAPDH was used as an endogenous control. Graphs represent a fold change in mRNA abundance with Control set as normal (1). The mean SEM normalized values are presented. Abbreviation: High A4, high androstenedione.

Figure 4.

Quantitative real-time polymerase chain reaction results in ovarian cortex pieces for StAR (A), LHCGR (B), CYP17A1 (C), CD68 (D), PECAM (E), KDR (F), NRP-1 (G), and VE-cadherin (H) in Control (white bars, n = 8) and High A4 (black bars, n = 6) dairy heifers. The geometric mean of GAPDH was used as an endogenous control. Graphs represent a fold change in mRNA abundance with Control set as normal (1). The mean SEM normalized values are presented. Abbreviation: High A4, high androstenedione.

Figure 5.

High-performance lipid chromatography-mass spectrophotometry analysis for different steroid hormones and metabolites of culture media collected after ovarian cortex culture for Control and High A4 beef heifers. Abbreviation: High A4, high androstenedione.

Figure 6.

Average numbers of follicles at different stages: (A) before culture and (B) after 7 d of culture in the High A4 and Control beef heifers. Collagen staining (Picro Sirus Red [PSR]—an indicator of fibrosis) for (C) Control and (D) High A4 ovarian cortex cultures. (E) Graph comparing the average area of PSR-positive staining per ovarian cortex field (pixels/μm²) between High A4 and Control beef heifers. Abbreviation: High A4, high androstenedione.

Figure 7.

Quantitative real-time polymerase chain reaction results in ovarian cortex pieces for PECAM (A), KDR (B), NRP-1 (C), and VE-cadherin (D) in Control (white bars, n = 4) and High A4 (black bars, n = 8) beef heifers. The geometric mean of GAPDH was used as an endogenous control. Graphs represent a fold change in mRNA abundance with Control set as normal (1). The mean SEM normalized values are presented. Abbreviation: High A4, high androstenedione.