Huang Liu,1,* Xuren Chen,2,* Xin Feng,3,* Zhiyong Zhu,1 Zhiwei Liao,4 Shenghui Zhu,1 Tao Pang,1 Xuejun Ren,5 Ruilin Yang6 

1Department of Andrology, National Health Commission (NHC) Key Laboratory of Male Reproduction and Genetics, Guangdong Provincial Reproductive Science Institute (Guangdong Provincial Fertility Hospital), Human Sperm Bank of Guangdong Province, Guangzhou, Guangdong, 510600, People’s Republic of China; 2Department of Andrology, the First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, 510080, People’s Republic of China; 3Department of Urology and Andrology, the First Affiliated Hospital of Sun Yat-sen University., Guangzhou, Guangdong, 510080, People’s Republic of China; 4Radiotherapy Department Area 4, Affiliated Cancer Hospital and Institute of Guangzhou Medical University, Guangzhou, Guangdong, 510095, People’s Republic of China; 5Guangdong Xingding Health Management Co., Ltd., Zhongshan, Guangdong, 528400, People’s Republic of China; 6Department of Andrology, the Affiliated Panyu Central Hospital of Guangzhou Medical University, Guangzhou, 511400, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Huang Liu, Email k114@163.com Xuejun Ren, Email 309044537@qq.com

Background: Spermatogenesis is a complex process that affects the outcome of fertility. Different types of cellular metabolic processes have both positive and negative effects on sperm production. Exploring new methods to promote spermatogenesis is the best way to improve fertility. This study confirmed the effect of astaxanthin on promoting spermatogenesis through various experiments.
Objective: To explore new activities of astaxanthin and develop the new methods to promote spermatogenesis.
Methods: Network pharmacology, in vitro cell culture and in vivo experiments were used in this research. The targets and potential signaling pathways of astaxanthin in the treatment of spermatogenesis, the effects on the proliferation and apoptosis of spermatogonial stem cells, and the therapeutic effect on oligoasthenozoospermia in mice induced with cyclophosphamide of astaxanthin were all observed. The ACSL3, VDAC, GPX4, FADS2, GLS2, Steap3, MDA, GSH-Px, and iron ions were detected and analyzed to reveal the potential regulatory mechanisms.
Results: Astaxanthin has 52 key targets for treating spermatogenesis, among which the oxidative stress metabolic pathway is one of the most important factors. The sperm concentration and forward motility of the oligoasthenozoospermia model mice fed with astaxanthin were significantly greater than those of the control group. The proliferation rate of spermatogonial stem cells cultured with astaxanthin was also significantly greater than that of quercetin group and the proportion of apoptotic cells was significantly lower. Astaxanthin can reduce ACSL3, MDA, and iron ions in spermatogonial stem cells; increase the expression of Steap3, VDAC, GPX4, GLS2, GSH-Px, and FADS2; and improve ester metabolism to promote spermatogenesis in oligoasthenozoospermia model mice.
Conclusion: Astaxanthin can regulate the metabolism of fatty acid through the ferroptosis pathway, and reduce the mitochondrial oxidative stress damage, and further regulate FADS2, Steap3, and other factors to promote spermatogenesis.

Keywords: astaxanthin, fatty acid metabolism, spermatogenesis, ferroptosis, oxidative stress damage