Research progress on novel bionic cryoprotectants in gamete and embryo cryopreservation

Cryopreservation technology has become a primary method for preserving animal genetic resources in the biomedical field. It achieves long-term storage by placing gametes or embryos in an ultra-low-temperature environment, enabling them to retain biological activity after thawing. However, the cytotoxicity issues associated with traditional cryoprotectants limit their application, making the development of non-toxic and highly effective novel cryoprotectants a current research priority. This review systematically reviews the development history and principles of cryopreservation technology, and summarizes the classification and mechanisms of action of cryoprotectants, with a particular focus on five types of novel cryoprotectants featuring bioinspired structural characteristics. Their ice-suppression performance and mechanisms of action are analyzed. These protectants possess structures similar to those of natural antifreeze substances and exhibit low toxicity, thereby demonstrating higher cryopreservation efficiency, and are thus referred to as novel bioinspired cryoprotectants. Furthermore, this review examines the potential applications of the aforementioned protectants in the cryopreservation of animal gametes (sperm, oocytes, and embryos), offering new insights into expanding the use of bioinspired cryoprotectants in the preservation of animal genetic resources.