The Endocannabinoid System (ECS)
The endocannabinoid system was only discovered in 1992 – ironically during research on cannabis. It is a complex cell-signaling system present in all mammals and plays a central role in maintaining homeostasis (internal balance). The ECS regulates many bodily functions, including sleep, mood, appetite, pain perception, immune response, memory, and reproduction.
The ECS consists of three main components: endocannabinoids (cannabinoids produced by the body, such as anandamide and 2-AG), cannabinoid receptors (CB1 and CB2), and enzymes responsible for the synthesis and breakdown of endocannabinoids (FAAH and MAGL).
Interestingly, CBD does not bind directly to CB1 or CB2 receptors like THC does. Instead, CBD acts as an allosteric modulator and influences the receptors indirectly. For example, it inhibits the FAAH enzyme, responsible for breaking down the endocannabinoid produced by the body, anandamide. Anandamide levels then increase in the body, which may contribute to the positive effects of CBD. Anandamide is also nicknamed the "bliss molecule" and plays an important role in regulating mood and pain perception.
CB1 Receptors
Central Nervous SystemCB1 receptors are primarily found in the brain and central nervous system – notably in the hippocampus, amygdala, basal ganglia, and cerebellum. They are involved in regulating pain perception, mood, memory, appetite, and motor control.
THC binds directly to CB1 receptors and thus causes the state of intoxication. CBD, on the other hand, acts as a negative allosteric modulator on CB1 – it slightly alters the shape of the receptor, so THC binds less strongly. This is why CBD can mitigate the psychoactive effect of THC. At the same time, CBD indirectly influences, via CB1, pain perception, anxiety, and mood.
CB2 Receptors
Immune System & PeripheryCB2 receptors are primarily found in immune cells, the spleen, tonsils, and gastrointestinal tract. They play a crucial role in regulating inflammatory processes and the body's immune response.
CBD has a higher affinity for CB2 receptors than for CB1 and acts as an inverse agonist. This means that CBD can modulate the activity of CB2 receptors, resulting in an anti-inflammatory effect. This property makes CBD particularly interesting for research on autoimmune diseases, chronic inflammation, and neurodegenerative diseases.
CBD effects beyond the ECS
The effects of CBD are not limited to the endocannabinoid system. CBD interacts with more than 65 different molecular targets in the body. Among the most important are:
Serotonin receptors (5-HT1A)
CBD activates the 5-HT1A serotonin receptor, which plays an important role in anxiety, depression, and nausea. This interaction explains CBD's anxiolytic and mood-regulating properties.
Vanilloid receptors (TRPV1)
CBD binds to TRPV1 receptors, involved in pain perception, inflammation, and body temperature. This activation may contribute to CBD's analgesic effect.
GPR55 receptors
CBD acts as an antagonist of the GPR55 receptor, sometimes called the 'third cannabinoid receptor'. Blocking this receptor could have anti-proliferative effects and is being researched in oncology.
PPAR-gamma receptors
CBD activates PPAR-gamma receptors, involved in regulating metabolism, inflammation, and cell proliferation. This activation presents neuroprotective and anti-inflammatory properties.
Source: Ibeas Bih, C. et al. (2015). "Molecular Targets of Cannabidiol in Neurological Disorders." Neurotherapeutics, 12(4), 699-730.
