Rewards and collagen: what do they have in common?

Dopamine! A seemingly simple molecule, but at the same time controversial!

It was identified as a neurotransmitter in 1957 and is one of the most important molecules in the field of reward.

But how does it work?

The expectation of a reward causes a spike in dopamine, which then drops. When the actual reward arrives, the dopamine level may rise again, exceeding, equalling or falling short of the first spike. The latter occurs if the expectation is too high compared to the experience itself, resulting in the dopamine level falling below the equilibrium value, causing the subject to experience real pain.

In general, pleasure and pain are produced in the same area of the brain: the body seeks pleasure, so after experiencing the dopamine rush, it tends to try to reproduce the same sensation. However, this dynamic, repeated over time, creates tolerance!

The more dopamine production is stimulated, the higher the concentration of dopamine needed to achieve the same level of gratification.

Each time, a new balance is established and sensitivity to pain increases (analgesia): this is neural adaptation!

Furthermore, the more intense the dopamine peak, the more the body will restore balance towards pain in an equally intense way; in addition, the faster the release of dopamine, the more addictive the substance is.

The peculiar thing is that the balance of dopamine concentration can be restored after three days of avoiding its stimulation, but the neural pathways built up due to the habit created by the subject and therefore their tendency to produce dopamine itself will remain present. It will therefore take time to create new neural pathways as a result of new habits.

But is that all dopamine does?

In fact, it is involved in many processes!

Here are some interesting facts:

• It facilitates communication between nerve cells.

• It connects different areas of the brain from the deepest part to the prefrontal cortex.

• There are 400,000 neurons that produce dopamine in the brain, and its precursor is synthesised by the brain and liver.

• It is involved in movement control and mood regulation.

• It is activated during decision-making and metabolic processes.

• It plays a role in the immune response and therefore also in the progression of cancer.

• It plays an important role in the onset of depression and schizophrenia.

• It is of fundamental importance in weight management, cravings and food regulation.

It is therefore not surprising that it is strongly associated with ADDICTION as one of the most relevant molecules, but also with the onset of insulin resistance and cognitive decline in diabetes.

Furthermore, in the presence of oxygen and ascorbic acid, it produces norepinephrine (which is simply the name for adrenaline when found in the brain), which then becomes epinephrine (when released throughout the body), thus becoming a precursor to cortisol.

Among other effects, this reduces collagen production and increases blood sugar and insulin levels. However, dopamine itself actually has a positive effect on bone remodelling, positively influencing bone density.

In addition, dopamine is believed to be linked to extra-personal space, in the sense that it is activated when the individual wants to reach something that is more than an arm's length away. For everything within reach, the molecules activated are those of peripersonal space (or the “here and now”), such as serotonin, oxytocin and endorphins.

When the hormones of the here and now are released, the release of dopamine is prevented.

But at the same time, depending on the biochemical pathway taken by dopamine itself, it can lead to the production of oxytocin.

It all depends on the reason why it is produced and the path it follows afterwards.

A simple yet highly complex molecule.

Did you know about these characteristics linked to dopamine?

Did you discover anything new?

Let me know if you want to find out what lies behind other molecules that affect our well-being!

Have a Blessed life,

Arianna

Bibliography:

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