Epigenetics, Depression & What You Can Do About It

Depression is a common mental illness that can affect a person’s ability to function in most aspects of life, but especially at work, in school, or with loved ones. If you are suffering from depression, or find yourself struggling with depression for the first time in your life in light of our current environment, you are not alone. In fact, according to the World Health Organization (WHO), depression affects more than 264 million people all over the world. Depressive symptoms vary and can include a variety of symptoms as seen below. 

Depression often  impacts multiple areas of one’s life, leading to decreased feelings of success or satisfaction at home or at work. In fact, major depressive disorder plays a big role in reduced  attendance and reduced functioning in the workplace or in school. It is associated with increased risk of substance abuse, domestic abuse, and divorce. People with depression may forget to take their medications, develop other medical conitions and even have  decreased sex drive. 

Research suggests that developing depression is a complex mix between your environment and your genetics. . Individuals with  major depressive disorder may have a close family member who also struggles with depression as the heritability (ability to inherit) is  estimated to be between 28 to 44%. Since traditional genetic analysis does not completely explain major depression, we have to look at other environmental factors such as  epigenetics.. While diagnosis and treatment have continued to advance, the emerging role of epigenetics offers additional insight and hope into better understanding the complexity of depression.

Epigenetics studies the changes in gene expression that are made without altering the DNA sequence. The influence of epigenetics on depression may be in the form of random events that occur during development or as inherited from family members. People  who are more vulnerable to depression (either from a genetic perspective or environmental factor), severe stress can trigger structural changes in chromatin -- the material in chromosomes composed of DNA and histone proteins -- at specific spots in the brain, which can affect gene expression in a way that may lead to depressive episodes. 

With the onset of the novel virus, many more people are experiencing depression. The prevalence of depression has increased significantly. Long duration of home confinement, increased  financial stresses, conflicting information from authorities, and concern over the health of oneself in addition to family members all increase sources of stress that may have contributed to the rise in depression. (source) 

Studies have shown that the increase  of DNA methylation (a type of epigenetics) on certain genes is associated with depression. Methyl groups are extra additions that can be added and removed to signal whether parts of the DNA should be copied or ignored. The body also uses methyl groups to turn genes on and off.. Stress exposure is one factor that can modify DNA methylation. It has been shown that stress early on in life can have lasting impacts on methylation that may last into adulthood (source1, source2). 

Another type of epigenetic change is with histones. Histones that help wrap up DNA  to help make the DNA structure more condensed. When DNA is more condensed, genes are blocked off for use. On the other hand, when DNA is loosened, gene expression can occur. Acetylation and methylation can then alter how loose or condensed the DNA is. In mice studies, when placed under the same stressful conditions, it was found that some mice would show depressive symptoms, labeled as “susceptible”, while others would not, which were labeled as “resilient.” Research found that mice missing the enzyme that adds methyl groups onto genes, lead to  a “susceptible” version of the mice and activation of the enzyme that promotes “resilience.” When enzymes called histone deacetylase (HDAC) removed an acetyl group from the histone, the DNA became less “open”. Interestingly, when HDAC inhibitors were given, depressive symptoms decreased in animals. 

Amidst this pandemic, you may be asking yourself, “now what?” Here are some steps you can take today to help balance your mood. 

• Mindfulness: mindfulness-based cognitive therapy (MBCT) focuses on teaching people to deal with their deeply ingrained negative thoughts in a new way. Studies have shown that people who complete MBCT show reduced symptoms and reduce recurrent episodes of depression, sometimes as well as medications (source). (source1) 
• Be in nature: being in nature can increase psychological well-being, in addition to improving sleep and lessening stress which are both risk factors of depression. (source) 
• Get enough omega-3 fatty acids: Consume more omega-3’s by either eating  more fish or taking omega-3 fatty acid supplements to help elevate your mood. 
• Get enough Folate/Vit B12: low levels of vitamin B12 and folate have also been linked to depression. Make sure to take some methyl folate and methyl B12 supplements to help decrease those depression symptoms. 
• Get enough magnesium: low magnesium levels have also been linked to depression. Rapid recovery from major depression has been seen in patients treated with magnesium supplements as well. (source) 

If you are interested in learning more about your own genetics or epigenetics and how it might relate to depression, check out the mytoolboxgenomics.com.

References:

1. Depression. 30 Jan. 2020, www.who.int/news-room/fact-sheets/detail/depression. 
2. Evans-Lacko, S, and M Knapp. “Global patterns of workplace productivity for people with depression: absenteeism and presenteeism costs across eight diverse countries.” Social psychiatry and psychiatric epidemiology vol. 51,11 (2016): 1525-1537. doi:10.1007/s00127-016-1278-4
3. Wu, Ping et al. “The relationship between depressive symptom levels and subsequent increases in substance use among youth with severe emotional disturbance.” Journal of studies on alcohol and drugs vol. 69,4 (2008): 520-7. doi:10.15288/jsad.2008.69.520
4. Ouellet-Morin, Isabelle et al. “Intimate partner violence and new-onset depression: a longitudinal study of women's childhood and adult histories of abuse.” Depression and anxiety vol. 32,5 (2015): 316-24. doi:10.1002/da.22347
5. Ho, Siew Ching et al. “Barriers and facilitators of adherence to antidepressants among outpatients with major depressive disorder: A qualitative study.” PloS one vol. 12,6 e0179290. 14 Jun. 2017, doi:10.1371/journal.pone.0179290
6. Nall, Rachel, and Janet Brito. Low Libido and Depression: What’s the Connection? 15 Aug. 2019, www.healthline.com/health/treating-hsdd/low-libido-and-depression. 
7. Fernandez-Pujals, Ana Maria et al. “Epidemiology and Heritability of Major Depressive Disorder, Stratified by Age of Onset, Sex, and Illness Course in Generation Scotland: Scottish Family Health Study (GS:SFHS).” PloS one vol. 10,11 e0142197. 16 Nov. 2015, doi:10.1371/journal.pone.0142197
8. Rogers, Donald, and Ronald Pies. “General medical with depression drugs associated.” Psychiatry (Edgmont (Pa. : Township)) vol. 5,12 (2008): 28-41.
9. Kang, Hee-Ju et al. “Comorbidity of depression with physical disorders: research and clinical implications.” Chonnam medical journal vol. 51,1 (2015): 8-18. doi:10.4068/cmj.2015.51.1.8
10. Negele, Alexa et al. “Childhood Trauma and Its Relation to Chronic Depression in Adulthood.” Depression research and treatment vol. 2015 (2015): 650804. doi:10.1155/2015/650804
11. Nestler, Eric J. “Epigenetic mechanisms of depression.” JAMA psychiatry vol. 71,4 (2014): 454-6. doi:10.1001/jamapsychiatry.2013.4291
12. Murgatroyd, Chris, and Dietmar Spengler. “Epigenetic programming of the HPA axis: early life decides.” Stress (Amsterdam, Netherlands) vol. 14,6 (2011): 581-9. doi:10.3109/10253890.2011.602146
13. Alonzi, Adam. “The Epigenetics of Depression.” What Is Epigenetics?, 28 Nov. 2017, www.whatisepigenetics.com/the-epigenetics-of-depression/. 
14. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 5th ed. Arlington (Virginia), American Psychiatric Publishing, 2013