Endocannabinoids and Kisspeptin Both Slow New Brain Cell Growth Through a Shared Pathway

Both anandamide and kisspeptin-10 reduced hippocampal neurogenesis by dampening ERK signaling. The TRPV1 ion channel receptor was upregulated by both treatments, suggesting it serves as a common mediator. Kisspeptin reduced CB1 receptor expression in the dentate gyrus, but anandamide did not affect kisspeptin receptors, indicating an asymmetric interaction between the two systems.

Male adolescent rats received kisspeptin-10 and/or anandamide, with or without the CB1 antagonist SR141716A. Expression of Kiss1, Kiss1R, CB1R, and TRPV1 was characterized in rat hippocampus. Neurogenesis was assessed alongside ERK signaling, SIRT1, BDNF, estrogen receptor alpha, and GAPDH expression.

Adult neurogenesis in the hippocampus is important for learning and memory. This study reveals a previously unknown regulatory partnership between the endocannabinoid and kisspeptin systems, both of which can slow new brain cell production. Understanding these mechanisms could inform approaches to cognitive decline and neurodevelopmental conditions.

The endocannabinoid system is already known to influence neurogenesis. This study adds the kisspeptin system as a partner in this regulation and identifies TRPV1 as a shared pathway, expanding the network of systems that fine-tune adult brain plasticity.

Only male adolescent rats were studied; sex differences and adult effects are unknown. The doses and routes of administration may not reflect physiological conditions. The interaction between these systems in humans has not been studied.