Investigation of kisspeptin’s effects on the human brain using fMRI
File(s)
Author(s)
Demetriou, Lysimachi
Type
Thesis
Abstract
Kisspeptin is a neuropeptide hormone vital in reproductive function. Its release in the hypothalamus activates GnRH neurons and downstream reproductive hormones. However, kisspeptin and its receptors are expressed in other regions of the brain and recently animal studies have investigated the effect of kisspeptin on different aspect of sexual, emotional and cognitive behaviour. Evidence show that similar expression patterns of kisspeptin are also present in parts of the human brain, but the effects on their function and any effects on behaviour are still unknown.
This thesis presents the first experiments to explore the effects of kisspeptin on the human brain and behaviour with kisspeptin administration in healthy men. The experiments employ functional magnetic resonance imaging (fMRI) as a measure of brain activity using various emotional and cognitive tasks.
The first fMRI experiment focuses on how kisspeptin modulates brain processing of visual tasks that include sexual, romantic bonding, aversive and neutral images as well as images of faces with different expressions (chapter II). Additionally, it investigates the effects of kisspeptin on the resting brain in the absence of any stimulus (chapter III).
The second fMRI study concentrates on how kisspeptin affects brain processing through different aspects of attraction (chapter IV). Specifically, the study employs a face attractiveness task using images of female faces of varying attractiveness, and an olfactory task which includes a feminine scent.
The results of these studies provide the first evidence that kisspeptin is an important modulator of brain activity particularly in the limbic system, in response to stimuli related to romantic or sexual behaviour in a healthy male population. The findings suggest that kisspeptin could be acting as an integrator between the hormone axis and emotional centres of the brain. Finally, these studies provide a basis for the development of kisspeptin as a potential therapeutic targeting the KP neurotransmitter system for people with psychosexual disorders.
This thesis presents the first experiments to explore the effects of kisspeptin on the human brain and behaviour with kisspeptin administration in healthy men. The experiments employ functional magnetic resonance imaging (fMRI) as a measure of brain activity using various emotional and cognitive tasks.
The first fMRI experiment focuses on how kisspeptin modulates brain processing of visual tasks that include sexual, romantic bonding, aversive and neutral images as well as images of faces with different expressions (chapter II). Additionally, it investigates the effects of kisspeptin on the resting brain in the absence of any stimulus (chapter III).
The second fMRI study concentrates on how kisspeptin affects brain processing through different aspects of attraction (chapter IV). Specifically, the study employs a face attractiveness task using images of female faces of varying attractiveness, and an olfactory task which includes a feminine scent.
The results of these studies provide the first evidence that kisspeptin is an important modulator of brain activity particularly in the limbic system, in response to stimuli related to romantic or sexual behaviour in a healthy male population. The findings suggest that kisspeptin could be acting as an integrator between the hormone axis and emotional centres of the brain. Finally, these studies provide a basis for the development of kisspeptin as a potential therapeutic targeting the KP neurotransmitter system for people with psychosexual disorders.
Version
Open Access
Date Issued
2019-05
Date Awarded
2019-10
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Wall, Matthew B.
Comninos, Alexander
Waljit, Dhillo
Sponsor
Invicro London
Publisher Department
Department of Medicine
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)