Kisspeptin (neurotransmitter): how it works in the brain

This hormone is linked to the regulation of sexuality and affection, among other things.

There are many substances and hormones that our body generates, many of which are still a mystery to science. From time to time different hormones and proteins are found that we did not know existed or the function they possessed until a certain research has found them. And with time, these substances are investigated in greater depth and new properties are discovered.

That's what happened with kisspeptina recently discovered hormone that is linked to the inhibition of metastasis and to the genesis of emotions related to affective-romantic bonding and sexual behavior.

What is kisspeptin?

Kisspeptin is a hormone that has been observed from puberty onwards in the hypothalamic-pituitary-gonadal axis of both sexes, and was discovered by a research team led by Lee in 1996 in the framework of research on cancers and their metastases. In fact, it was it was initially named metastin because its discovery was associated with the suppression of metastasis.. It was not until 2001 that it received its new name, after seeing the effect that its absence had on the onset of puberty.

The term kisspeptin actually refers to a set of different peptides associated with a set of different peptides derived from a precursor common to all of them and encoded common to all of them and which is encoded by the Kiss1 gene.

It is an endogenously generated substance, thus being synthesized naturally by our organism. It is mainly secreted in the hypothalamus and the hypothalamic-pituitary-gonadal axis, although it has also been discovered that this hormone is generated in large quantities in the placenta. Its function is based on its binding to its receptor, GPR54, which is bound to the G protein (which in turn acts as a transmitter of information from a particular receptor to other proteins).

The receptors for this hormone have been found to be distributed throughout the brain and nervous system, although it is possible that they may be located throughout the brain and nervous system. and nervous system, although it is possible to find a much more massive concentration in the anteroventral and arcuate nuclei of the same structure that seems to generate it, the hypothalamus. It also appears in the medulla oblongata, in the preoptic nucleus and in the medulla, being associated with the sexual response. Pancreas, adrenal cortex, liver, gonads and Blood vessels are other structures in which it has been localized, producing different effects.

Kisspeptin has a certain sexual dimorphismThe following is a general rule: at the level of the anteroventral paraventricular nucleus, kisspeptin is much more present in females than in males (at least in rodent experiments), reducing the levels of this hormone and its receptors in this area by massive exposure to androgens during gestation.

Functions in which this substance is involved

Kisspeptin is a hormone with an important role in our body, exerting different functions in different systems. Although many of them are unknown, among the most known and researched we can find the following.

1. Awakens libido

Kisspeptin is deeply linked to libido and sexual behavior, participating in the regulation of gonadal hormones. In fact, it has been observed that injections of this hormone generate in male mice a higher level of attraction towards females of the same species, generating a higher level of interaction between them and producing a rapprochement. In humans, it has been shown that increases the level of excitation and the level of attraction generated by romantic and erotic images.

This alteration comes from the activation of the neurons of the medial posterodorsal part of the amygdala (linked to sexual appetite), as well as due to one of the main functions that have been observed at a biological level: stimulate the secretion of gonadotropin-releasing hormone.. In fact, it has been suggested that this hormone has a high potential to combat sexual dysfunctions.

This aspect has been observed mainly in males, and more research is needed on the effects of kisspeptin on female sexual behavior. However, it has been observed to cause an increase in luteinizing hormone levels (although the level of increase depends on the time of the menstrual cycle at which it is administered).

2. Promotes romanticism

Kisspeptin not only has a positive effect at the sexual level, but it has also been associated with an emotional component that facilitates the experience of romantic feelings and love, as well as the detection and appreciation of romantic feelings.as well as the detection and appreciation of it.

3. It contributes to regulate the emotional response

The research carried out with human beings reflects that before an injection of kisspeptin, not only libido and romanticism increase but also the regulation of negative emotions is enhanced. It facilitates relaxation and management in such a way that discomfort and stress are reduced. The possibility is raised that it could be used in the pharmacological treatment of different mental disorders. different mental disorders.

4. Reduces anxiety

Linked to the previous point, kisspeptin is also linked to a reduction in the level of anxiety, having as we have mentioned effects on the amygdala. This aspect has been observed in several animal models, generating a relaxation of behavior and lower levels of stress. In humans, this could be associated to a decrease of anxiety in the different anxiety disorders in different anxiety and obsessive disorders, as well as the anxiety that causes many cases of erectile dysfunction.

5. It affects maturation and development

A relationship has been found between kisspeptin and puberty, modifying the moment in which it occurs. The administration of kisspeptin stimulates the synthesis of gonadotropin-releasing hormone and generates a earlier entry into puberty. In women, it plays an important role in initiating the menstrual cycle.

6. Inhibits or hinders metastasis.

In addition to its functions in the affective-sexual sphere, kisspeptin is a really relevant hormone in the treatment of different types of cancer. really relevant in the treatment of different types of cancer.. It has been observed that this hormone has a metastasis-suppressing effect on cancers such as breast, ovarian, kidney, lung and skin cancer. In fact, the research in which this hormone was found is mainly linked to this type of application.

7. Participates in vasoconstriction

It also has an effect at the vascular level, participating in vasoconstriction and finding a certain link between kisspeptin and arteriosclerosis.

8. Contributes to the regulation of insulin levels.

Kisspeptin has been found to be localized in the pancreas, participating in the synthesis and emission of insulin through the islets of Langerhans. (in which kisspeptin can be found). There is some research linking this hormone to diabetes.