We all feel sad, moody or low from time to time, many people experience these feelings deeply, for long periods (weeks, months or even years) and sometimes without any obvious reason. Depression can be defined as a morbid sadness, dejection, or a sense of melancholy distinguished from grief. Depression falls under the broader category of Major Depressive Disorders (MDD) which is characterized by a single isolated episode lasting weeks to months. Global estimates by WHO (2017) indicate that 4.4% of the global population suffers from a depressive disorder, and 3.6% from an anxiety disorder. It is estimated that approximately 38.2% of the EU population suffers from a mental disorder each year. The most frequent disorders are anxiety disorders (14%), major depression (6.9%), According to The Mental Health Foundation, between 4-10% of people in England will suffer from depression in their lifetime and total economic burden of depression only in the United States was estimated at 83.1 billion US dollars in 2000. The main challenge to be addressed across Europe is the limited availability of financial resources for mental disorders (MDD).
How depression affects your brain
Our brain is continuously changing. The brain cells are neurons; these neurons make and break connections all the time. Hippocampus is a part of the brain that is responsible for neural regeneration (growth of new neurons) throughout our lives. This region (Hippocampus) of the brain can get damaged or shrink during suffering from depression. In the hippocampus, for example, noticeable changes can occur anywhere from 8 months to a year during a single bout of depression. Depression also affects thalamus, amygdale, frontal, prefrontal cortices. The amount these areas shrink is linked to the severity and length of the depressive episode lasts.
Depression is more than just a low mood – it's a serious condition that affects
your physical and mental health.
Depression and its symptoms
The main causes of depression and anxiety are not yet identified; researchers consider that it can be a combination of problems such as stressful life events, chemical imbalances inside the brain, genetic disposition, social isolation, other emotional disorders, a medication which is taken and other medical reasons.
Some of the symptoms of depression include:
- Thoughts of death, dying or suicide, sleeping problems
- Weight gain loss or and change in appetite
- Loss of interest or pleasure in almost all activities
- Low esteem and feelings of worthlessness
- Loss of energy or fatigue
In the UK selective serotonin re-uptake inhibitors (SSRIs) are commonly prescribed antidepressants. These help to increase serotonin levels – the chemical – or neurotransmitter – in the brain which is often called the ‘happy chemical’ as it helps to give you feelings of happiness and well-being. These antidepressants, however, are not suitable for everyone – some are not prescribed for those under 18 or some are not suitable for ladies who are pregnant or breastfeeding. Currently available antidepressants have a substantial time lag to induce therapeutic response and relatively low efficacy.
During depression, the brain is affected especially it causes damage to the
hippocampus. The hippocampus is the region responsible for neural regeneration and is the exact area of the brain that is normally atrophied in depressed people. However, some studies show that hippocampus can and does recover and the process of neural regeneration can be stimulated which will reduce the effects of depression.
Endocannabinoid System (ECS)
The endocannabinoid system (ECS) is a complex cell-signalling system. ECS plays a role in regulating many functions and processes like sleep, mood, appetite, memory, reproduction, and fertility, etc inside the body. There are three basic components of the Endocannabinoid System (ECS).
Endocannabinoids are molecules produced within our body. Endocannabinoids assists in maintaining the smooth internal function of the body. Anandamide (AEA) and 2-arachidonoylglyerol (2-AG) are identified as endocannabinoids. Endocannabinoid receptors are found in our bodies. Endocannabinoids bind with these receptors to signal the ECS if any action is needed. CB1 Endocannabinoid receptors found in (CNS) Central Nervous system) and CB2 Endocannabinoid receptors found in (PNS) Peripheral Nervous system. Once endocannabinoids have carried out their function, enzymes are used for their breakdown. One of the endocannabinoids, anandamide, can stimulates neurogenesis and reduces depression if it is present in the body in sufficient quantities.
Brain-derived Neurotrophic Factor (BDNF)
The BDNF gene provides instructions for making a protein found in the brain and spinal cord called a brain-derived neurotrophic factor. This protein promotes the survival of nerve cells (neurons) by playing a role in the growth, maturation (differentiation), and maintenance of these cells. Increasing the levels of BDNF in the hippocampus reduces the effect of depression. As the signalling of BDNF increases in the brain, it stimulates antidepressant-like effects.
Serotonin is a "hormone of happiness” and from a chemical point of view, serotonin is a 5-hydroxy tryptamine derivative and is often referred to as 5-HT. Serotonin binds at serotonin receptors (also called 5-HT receptors). Natural substances that can mimic serotonin by binding and activating our serotonin receptors may reduce the effects of depression and assist recovery.
Never stop taking prescribed medication, without talking to your healthcare provider first. Suddenly stopping the medication that’s been prescribed to you may cause serious side effects.