# Anthocyanins Alleviate Persistent Corpus Luteum and Ovarian Quiescence in Beef Cows by Modulating Gut Microbiota and Reducing Granulosa Cell Apoptosis

## TL;DR

Anthocyanins improve ovarian function in beef cows by balancing gut bacteria and protecting ovarian cells from damage.

## Contribution

This study demonstrates that anthocyanins can alleviate ovarian dysfunction in beef cows through gut microbiota modulation and reduced cell apoptosis.

## Key findings

- High-dose anthocyanins increased large follicle numbers and reduced persistent corpus luteum in cows.
- Anthocyanins altered gut microbiota by increasing beneficial bacteria and decreasing harmful ones.
- Anthocyanins reduced oxidative stress and cell apoptosis in ovarian granulosa cells.

## Abstract

Ovarian disorders like persistent corpus luteum and ovarian quiescence can reduce the reproductive ability of female beef cattle, negatively impacting the cattle industry. This study explored whether anthocyanins could help improve ovarian function. We fed anthocyanins to cows with ovarian problems and found that higher doses increased the number of growing follicles, lowered harmful hormone levels, and changed the types of bacteria in the gut. Anthocyanins also protected ovarian cells from damage caused by oxidative stress. These results suggest that anthocyanins could be a natural and safe way to support cattle reproduction by balancing gut bacteria and protecting ovarian cells. This research offers a promising approach to enhancing cattle breeding and supports the use of natural antioxidants in livestock management.

Persistent corpus luteum (PCL) and ovarian quiescence (OQ) are key manifestations of ovarian dysfunction (OD) that lead to reduced reproductive capacity in beef cattle, posing a serious challenge to the industry. Anthocyanins (ACNs) are known for their antioxidant properties. This study aimed to investigate the regulatory effects of ACNs on PCL and OQ and to explore the underlying mechanisms. Forty-eight beef cows diagnosed with both OQ and PCL were selected and continuously fed ACNs for 60 days. The results showed that the regulatory effects of ACNs were dose-dependent. A high dose of ACNs (ACNH) significantly increased the number of large follicles and reduced the occurrence of PCL. ACNH treatment significantly decreased serum progesterone (P4) levels and increased estradiol (E2) levels. Furthermore, ACNH reduced microbial diversity in OD cows but significantly increased the abundance of Patescibacteria, Actinobacteriota, Proteobacteria, and Chloroflexi, while decreasing the abundance of Desulfobactera, indicating that ACNs may affect ovarian function by regulating the gut microbial environment. In an ovarian granulosa cell model of oxidative damage, ACN intervention could reduce oxidative stress levels and mitigate oxidative damage. ACNs downregulated various pro-apoptotic genes, such as P53, Fas, and Bax, while upregulating anti-apoptotic genes Bcl-2 and Bcl-xL, suggesting that ACNs significantly inhibit cell apoptosis. To conclude, these results demonstrate that ACNs improve the ovarian function of beef cows by regulating gut microbiota and reducing oxidative stress-induced apoptosis in ovarian granulosa cells, thereby enhancing the reproductive capacity of beef cattle that show reproductive disorders. These findings provide a theoretical basis for the application of ACNs in the cattle industry and showcase their potential value as natural antioxidants.