In vitro fertilization using sperm activated by ML‐2–3 isolated from Morinda lucida Bentham leaves

• Published in: Reproductive medicine and biology Vol. 21; no. 1; pp. e12455 - n/a
• Main Authors: Ohta, Tomoe, Uto, Takuhiro, Shoyama, Yukihiro, Sakyiamah, Maxwell Mamfe, Appiah, Alfred Ampomah, Tanaka, Hiromitsu
• Format: Journal Article
• Language: English
• Published: Japan John Wiley & Sons, Inc 01.01.2022; John Wiley and Sons Inc; Wiley
• Subjects: Acrosin; Acrosome reaction; computer‐assisted sperm analysis; Embryos; Experiments; Females; In vitro fertilization; Infertility; Laboratory animals; Morinda lucida; Motility; Original; Polyvinyl alcohol; Potassium; Pregnancy; refrigerated sperm; Sperm; tetracyclic iridoids; Toxicity; Japan; computer‐assisted sperm analysis; tetracyclic iridoids; refrigerated sperm; acrosome reaction; infertility
• ISSN: 1445-5781; 1447-0578
• DOI: 10.1002/rmb2.12455

Purpose ML‐2–3 is a novel tetracyclic iridoid derived from Morinda lucida Bentham leaves. This compound has anti‐trypanosomal and anti‐leishmanial effects. In this study, the authors investigated effects of ML‐2–3 on in vitro fertilization (IVF) rates, motility, and acrosome reaction of the mouse sperm. Methods IVF was performed using sperm from BALB/cByJJcl mice treated with ML‐2–3. Computer‐assisted sperm analysis (CASA) was performed on the sperm of C57BL/6J mice to investigate sperm motility. The effect of ML‐2–3 on the acrosome reaction was examined by observing the fluorescence of sperm labeled with the acrosin‐EGFP transgene. Results ML‐2–3 improved IVF in BALB/cByJJcl mice with low fertilization rates. The optimum concentration of ML‐2–3 in sperm pre‐culture medium was 20 µM, and no significant toxicity of ML‐2–3 was observed in developing embryos at this concentration. ML‐2–3 affected sperm motility but not the acrosome reaction. ML‐2–3 increased the IVF rate of mouse sperm that had been refrigerated for 3 days. Conclusions ML‐2–3 can improve the outcome of IVF and motility without inducing the acrosome reaction in mice. These effects of ML‐2–3 on sperm behaviors are different from those of the similar drugs. ML‐2–3 is a novel tetracyclic iridoid derived from Morinda lucida Bentham leaves. Computer‐assisted sperm analysis indicated that ML‐2–3 affected sperm motility but not the acrosome reaction. Our results indicate that ML‐2–3 activates sperm using a molecular mechanism that differs from those used by other compounds known to activate sperm for IVF.