Investigation of endocannabinoid 2-AG and its hydrolases for regulation on sperm motility and acrosome reaction in Kunming mice.

Context 2-AG (2-arachidonoyl glycerol), a key endocannabinoid, regulates sperm hyperactivation in humans via ABHD2 (alpha/beta hydrolase domain-containing protein 2)-mediated CatSper calcium channel activation. However, ABHD2's role in mice is unclear, while MAGL (monoacylglycerol lipase), ABHD6 (alpha/beta hydrolase domain-containing protein 6), and ABHD12 (alpha/beta hydrolase domain-containing protein 12) modulate 2-AG in the mouse CNS (Central Nervous System). Aims This study explored 2-AG's impact on mouse sperm motility, its regulatory mechanisms, and the involvement of MAGL, ABHD6, and ABHD12. Methods 2-AG (2-arachidonoyl glycerol) levels in caput and caudal epididymal sperm from Kunming mice were quantified. ABHD2/6/12 (alpha/beta hydrolase domain-containing protein 2/6/12) and MAGL (monoacylglycerol lipase) were identified, localized, and assessed for roles in motility and Ca²⁺ influx. Key Results Caput sperm exhibited higher 2-AG levels than caudal sperm. Four hydrolases regulated motility via 2-AG hydrolysis to induce calcium influx. MAGL showed the strongest hydrolytic activity, ABHD2 the weakest. Subcellular localization revealed MAGL in midpiece, ABHD12 in midpiece and principal piece, and ABHD2/ABHD6 in acrosomal region. Conclusions 2-AG modulates mouse sperm motility via calcium signaling. MAGL, ABHD6, and ABHD12 drive 2-AG hydrolysis, while ABHD2 is linked to acrosome exocytosis, not 2-AG breakdown. Implications Targeting MAGL/ABHD12 offers non-hormonal contraceptive strategies or ART improvements. Monitoring 2-AG and hydrolase activity could aid in diagnosing male infertility.