Introduction:
Brain-derived neurotrophic factor (BDNF) plays an important role in various functions of the brain. It is a protein that helps keep our brain healthy. Recent studies have found that BDNF has a role in mood disorders like bipolar disorder and depression. There are intensive studies that are being carried out to understand how the BDNF levels affect mood disorders. Studies have noted that the way BDNF works in the brain is complex.
What Is BDNF?
BDNF is considered to be important for the development and growth of the brain and nervous system. It helps brain cells to grow, stay healthy, and work efficiently.
Neurotrophins are chemicals found in the brain and nervous system. These are responsible for the smooth working of brain cells. Hence, the person can properly think, have good memory, and act on the signals sent by the brain.
BDNF is produced in various regions of the brain. These include:
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Hippocampus (learning and memory).
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Prefrontal cortex (decision making, mood regulation).
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Amygdala (emotions and fear responses).
Higher concentrations of BDNF are found in the hippocampus and cortex (outermost layer of the brain).
Many factors are responsible for your levels of BDNF. These include:
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Exercise: If you exercise regularly, especially aerobic exercise may help increase your levels of BDNF.
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Stress: If you experience persistent stress, it may reduce your levels of BDNF.
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Sleep, Nutrition, and Social Interactions: These factors may influence your levels of BDNF.
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Genetic Variation: Genetic variations like Val66Met polymorphism may alter BDNF function or expression.
What Is the Neurobiology of Mood Disorders?
Mood disorders are conditions in which there are constant alterations in a person's mood. This can also be known as an unstable emotional state. The most common mood disorders are depression and bipolar disorder. The two conditions are quite different from each other.
Depression is characterized by constant sadness and a lack of interest in performing activities. Bipolar disorder is a condition in which a person oscillates between episodes of mood (unpredictable mood). A person may exhibit constant change between depressive and manic episodes. The symptoms of both conditions may differ, but their effects on one’s personal life are considered to be huge.
What Are the Genetics of BDNF and Its Role in Mood Disorders?
The genetics of how BDNF and mood disorders are quite complex. The main problem is seen in the polymorphism of the BDNF gene. Val66met is the polymorphic gene in BDNF. When this gene is affected, there is an alteration in the secretions and functioning of this gene. Individuals carrying this polymorphism gene exhibit intracellular trafficking of this gene, leading to its shortage in secretion. This pathogenesis is considered a biomarker for mood disorders and regulation.
What Is the Relationship Between BDNF and Depression?
BDNF is found to be related to mood problems like depression. It was observed from studies that people affected with depression usually have low levels of BDNF in their blood. Low levels of BDNF, especially in the regions of the hippocampus and prefrontal cortex regions may affect a person’s memory, thinking, and mood.
The link between BDNF and depression can be explained in the brain. BDNF is a protein that helps keep the brain cells and their connections healthy. In depression, these connections may not work properly. This may affect the whole nervous system. Over a period of time, the brain may change how it looks and works. These changes may lead to depression and mood disorders.
The primary cause of depression is found to be stress. Stress is also a direct cause of lowered levels of BDNF. Chronic stress has been associated with reduced expression of the BDNF gene. This highlights the importance of neurotrophins in regulating mood disorders.
What Is the Relationship Between Bipolar Disorder and BDNF?
In bipolar disorder, the link with BDNF is found to be a little complicated. It was noted that in the manic phase (feeling overly energetic and excited), a person may have higher levels of BDNF. It was also observed that if a person is depressed (feeling low or sad), the levels of BDNF are found to be low. This variation in the levels of BDNF explains the role of BDNF in the regulation of mood.
Studies have shown that increased levels of BDNF are linked with hyperactivity and impulsive behavior. This is the same as in manic episodes or the highs of bipolar disorder. A decrease in BDNF levels tends to produce symptoms related to depression. These symptoms can be correlated to the lows of bipolar disorder.
What Are the Therapeutic Uses of BDNF?
Many studies are being conducted to determine whether BDNF can help treat mood disorders. These studies have found that increasing the levels of BDNF can help improve mood. Studies are being conducted to know the different ways to increase the levels of BDNF. Hence, it was thought that BDNF can improve mood as well as overall well-being.
The various ways in which BDNF can be used as a therapeutic agent are as follows:
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Usage of BDNF as an Antidepressant: Antidepressants such as SSRIs (selective serotonin reuptake inhibitors) have been shown to increase BDNF levels. Increased BDNF levels help in improving the mood and fighting against depression.
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Exercise as a Neuromodulator: Exercise is known as a great neuromodulator. It has been observed that regular exercise has caused BDNF to be released to its optimum levels. It is also considered a non-pharmacological treatment for mood disorders. Further exploring BDNF-exercise-induced mood regulation can lead to mindfulness and novel therapeutic strategies.
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Mind-Body Practices: Mind-body practices such as practicing mindfulness can be a great regulator of mood disorders. Ancient practices such as meditation and yoga can be beneficial in reducing stress levels. Reduced stress levels can, in turn, be beneficial for lowering mood disorders.
What Is the Way Ahead?
The relationship between BDNF and mood disorders goes much beyond just correlations. However, much research has to be done to consider it a viable treatment modality. The complexity of the genetic basis of BDNF requires more studies. However, it is vital to study the temporal alterations during mood disorders to understand the role of BDNF.
Conclusion
BDNF's role in mood disorders shows the delicate interplay between neurobiology and mental health. The evolving landscape of research continues to understand the complexities of BDNF and its implications for depression and bipolar disorder. Studies are being done to know about the molecular and genetic aspects of BDNF to make a breakthrough in newer interventions to treat the challenges of mood disorders.
Key Takeaways from iCliniq
BDNF is a chemical produced in the brain. It plays a key role in mood disorders. The variations in their levels are found to be responsible for mood disorders. Hence, it is important to understand the role of BDNF.
