Endocannabinoid Tone and Epilepsy

Epilepsy is a neurological disorder where uncontrolled electrical activity in the brain causes frequent seizures and temporarily disrupts brain activity.

The name epilepsy is a general term used to refer to most seizure disorders, so the cause, severity and type of the seizure can vary.

According to Epilepsy Action, there are over 600,000 people with epilepsy in the UK.

It can affect people of any age, but it most commonly starts in childhood or after the age of 60.

For most people, it is a lifelong condition, but it can sometimes improve over time.

Epilepsy can be caused by a range of conditions and situations, including genetics, stroke, head injury, infection or brain tumour. However, in many cases, there is no apparent cause.

The main symptom of epilepsy is seizures, but they can vary in cause and how they affect the sufferer.

For some people, the seizure causes muscles to contract and the whole body to shake or jerk. For others, it can be a lack of awareness or strange sensations.

Some common symptoms of seizures include:

• Temporary confusion
• Staring at nothing
• Stiff muscles
• Uncontrollable muscle contractions and jerking of the arms and legs
• Loss of consciousness 
• Sensations of fear, anxiety or déjà vu

The main types of seizure are:

Focal (simple partial) seizures – These are generally mild sensations or muscle twitching. In some cases, they can precede a more significant attack.

Focal (complex partial) seizures – This type of seizure includes loss of awareness and uncontrolled body movements.

Tonic-clonic seizures - This is a two-stage seizure and is what most people consider to be a typical epileptic fit. During the first (tonic) stage, your body stiffens. During the second (clonic) stage, the muscles contract and your arms and legs will jerk about. 

Absences – This is when you lose awareness of your surroundings for a short time. These seizures can look like daydreaming or staring into space, although in some cases, there may be some mild jerking of limbs.

Other types of seizures include myoclonic seizures, clonic seizures, tonic seizures, atonic seizures and status epilepticus.

For many people, their seizures appear to start entirely at random. However, for others, there seems to be a trigger. Some common triggers are stress, poor sleep, alcohol, medication and flashing lights.

There are several treatments available for epilepsy. 

Medication, diet changes and surgery can reduce the severity and frequency of seizures. In some cases, doctors have been able to stop seizures altogether.

CBD and Your Endocannabinoid Tone

CBD works in your body in many different ways, but one of the most vital interactions is how it stimulates the endocannabinoid system (ECS) and raises your endocannabinoid tone:

What is the endocannabinoid system?

The endocannabinoid system is a collection of signal molecules (endocannabinoids), receptors and enzymes.

It's active throughout the body, particularly in the central and peripheral nervous systems. 

When the ECS is activated, it makes tiny chemical adjustments that enhance the signalling capacity of cells within your body.

This allows your body systems to communicate effectively and quickly restore a healthy balance following damage or illness.

What is your endocannabinoid tone?

Endocannabinoid tone refers to the level of potential endocannabinoid activity in your body and the ability of your endocannabinoid system to respond to any problems.

This can be affected by a range of factors, including genetics, diet, stress and disease.

If your endocannabinoid tone is low, your endocannabinoid system is unlikely to be able to restore your body systems to a state of healthy balance. As a result, you may feel unwell or experience symptoms related to anxiety. 

Regular consumption of CBD can stimulate the action of your endocannabinoid system (ECS) and raise your tone. 

To learn more about how CBD raises your endocannabinoid tone, you can read our article: Endocannabinoid Tone and CBD.

Key terms:

CB1 and CB2 – These are the most common endocannabinoid receptors.

• CB1 is found in the central nervous system.
• CB2 is present in the central nervous system, the peripheral nervous system and in immune cells throughout the body.

Anandamide (AEA) and 2-Arachidonoylglycerol (2-AG) – These are endocannabinoid signalling molecules present in humans and animals. They can interact with a range of chemical receptors, including CB1 and CB2.

Endocannabinoid Tone and Epilepsy

Neurons transmit messages using electrical pulses; in a healthy brain, there will be an irregular pattern of electrical signals being fired independently.

For someone with epilepsy, a seizure occurs when the electrical signals in one area all begin to fire simultaneously.

Where this pattern originates from dictates what symptoms will be caused by the seizure.

For example. A seizure that originates in the hippocampus is likely to affect memory.

In recent years, many studies have found that endocannabinoid tone can influence the severity and frequency of seizures in several different ways.

These are two of the most common:

Neuroinflammation

Although there is no clear understanding of a common cause of epilepsy, some scientists suggest that it could be caused by neuroinflammation.

Neuroinflammation is the swelling of brain tissue after damage, illness or immune system disorder.

Neuroinflammation is a normal response to brain injury or illness, but people who develop epilepsy seem to be unable to switch the inflammation off. The continued inflammation can lead to a seizure and then to epilepsy.

The chemical pathways involved with the brain’s inflammatory mechanisms are closely linked to the endocannabinoid system.

Consequently, a person’s endocannabinoid tone will likely influence how the inflammation will behave. 

When the endocannabinoid receptors CB1 and CB2 are activated in the brain, they engage in a range of interactions that exert controlling effects on inflammatory processes. 

Studies have found that the levels of anandamide (human cannabinoid) and the enzymes that synthesise 2-AG in the hippocampus are lower in people with epilepsy. 

They also found that if a patient has a higher endocannabinoid tone before a seizure, it will likely be of lower intensity.

Consequently, the endocannabinoid system offers doctors a unique opportunity to find a way of controlling neuroinflammation and possibly reducing the severity of seizures.

Synaptic Transmission

One of the main actions of the endocannabinoid system in the brain is to regulate the messages transmitted across synapses.

The synthesis and interactions of endocannabinoids and receptors take a vital role in a complex network of interactions that finetune the transmissions sent at the synapse.

Several studies have found evidence that this action can reduce neuronal excitability and protect against the kind of electrical firing that occurs during a seizure.

This may be one of the ways that brains compensate for irregular activity during seizures.

It may also indicate that someone with a higher endocannabinoid tone will have fewer or less intense seizures.

Contradictory Results

In both the actions described here, the research is far from conclusive.

While many studies demonstrate the links between the endocannabinoid system and epilepsy and the therapeutic benefits of a high endocannabinoid tone, exactly how the precise mechanisms work is complex and contradictory.

Several of the studies referenced here found that endocannabinoid activity produced completely different results in different areas of the brain.

So, while we are a lot closer to understanding how a high endocannabinoid tone can protect against epilepsy, there is still a lot more to uncover.