Sperm-Guiding Unconventional Prostaglandins in C. elegans: Synthesis and Signaling

Abstract

Prostaglandins comprise a family of lipid signaling molecules derived from polyunsaturated fatty acids and are involved in a wide array of biological processes, including fertilization. Prostaglandin-endoperoxide synthase (a.k.a. cyclooxygenase or Cox) initiates prostaglandin synthesis from 20-carbon polyunsaturated fatty acids, such as arachidonic acid. Oocytes of Caenorhabditis elegans (C. elegans) have been shown to secrete sperm-guidance cues prostaglandins, independent of Cox enzymes. Both prostaglandin synthesis and signal transduction in C. elegans are environmentally modulated pathways that regulate sperm guidance to the fertilization site. Environmental factors such as food triggers insulin and TGF-β secretion and their levels regulate tissue-specific prostaglandin synthesis in C. elegans. This novel PG pathway is abundant in mouse and human ovarian follicular fluid, where their functions, mechanism of synthesis and pathways remain to be established. Given the importance of prostaglandins in reproductive processes, a better understanding of how diets and other environmental factors influence their synthesis and function may lead to new strategies towards improving fertility in mammals.

Contaminants of Emerging Concern (CECs) and Male Reproductive Health: Challenging the Future with a Double-Edged Sword

“…These compounds are widely used for their analgesic, antipyretic, and antiinflammatory properties [116]. The PG family consists of lipid-signaling molecules derived from polyunsaturated fatty acids and are involved in a variety of biological processes, including fertilization [117]. As a result, they regulate human reproduction, neurological function, cancer progression, and inflammation and serve as short-lived, local hormones [117].…”

“…The PG family consists of lipid-signaling molecules derived from polyunsaturated fatty acids and are involved in a variety of biological processes, including fertilization [117]. As a result, they regulate human reproduction, neurological function, cancer progression, and inflammation and serve as short-lived, local hormones [117]. An association has been suggested between PGs and sperm motility as PGF1α binds with high affinity to the sperm calcium channel (CatSper), which in mammalian spermatozoa is crucial for generating hyperactivated motility and therefore fertilization [117].…”

“…As a result, they regulate human reproduction, neurological function, cancer progression, and inflammation and serve as short-lived, local hormones [117]. An association has been suggested between PGs and sperm motility as PGF1α binds with high affinity to the sperm calcium channel (CatSper), which in mammalian spermatozoa is crucial for generating hyperactivated motility and therefore fertilization [117]. In addition to their role in the regulation of testicular functions, PGs have been suggested to exert stimulatory as well as inhibitory effects on spermatogenesis [66].…”

Released ATP Mediates Spermatozoa Chemotaxis Promoted by Uterus-Derived Factor (UDF) in Ascaris suum

“…The hormones prostaglandins and progesterone have been identified as chemoattractants of mammalian sperm [ 8 , 9 ]. F-series prostaglandins synthesized by oocytes from polyunsaturated fatty acid (PUFA) precursors guide Caenorhabditis elegans sperm to spermatheca [ 10 , 11 ]. These chemoattractants induce spermatozoa to regulate their flagellar beating, motility direction, and size and shape during migration to oocytes.…”