Oxidative stress to the cells of the human body has the potential for numerous, potentially deadly, consequences including cardiovascular disease, cancer, diabetes, renal disease, irritable bowel disease, and bipolar disorder (NIST, 2013). Antioxidants, such as copper, zinc, selenium, amino acids and vitamins A, C, and E, act to negate the harmful effects of free radical damage caused by oxidative stress. Recent research into the pathophysiology of bipolar disorder has discovered a connection between oxidative damage to the central nervous system and the severity of symptoms experienced in those diagnosed with bipolar disorder (Steckert et al, 2010). This new research suggests antioxidants could play a role in delaying the onset of bipolar disorder and reducing the frequency and severity of symptoms.
Oxidation is the process by which atoms lose electrons during metabolism and energy production (Thompson & Manore, 2009). This loss of electrons can cause the atoms to become unstable and form free radicals, which can damage tissues, cells, and DNA. Free radicals are volatile atoms with an uneven number of electrons orbiting the nucleus. In order to stabilize themselves, these atoms filch electrons from other atoms, creating more free radicals and starting a chain reaction of free radical formation (Thompson & Manore, 2009). The damage to other cells of the body through the formation of free radicals is known as oxidative damage or oxidative stress (Medeiros, 2012). The location of the free radical formation determines the effects oxidative stress can have on the body; bipolar disorder is believed to be caused by oxidative damage to the brain, particularly the areas involved in attention, emotion, and cognitive functions, as well as damage to the spinal cord and central nervous system (Wang et al, 2009).
Antioxidants work to reduce oxidative damage by donating electrons to free radicals and ending the chain reaction of free radical formation (Thompson & Manore, 2009). Antioxidant compounds include amino acids, vitamins, and minerals. Antioxidant action is just one of hundreds of possible functions of amino acids such as lutein and lycopene. Beta-carotene, vitamin C, and vitamin E all function as both vitamins and antioxidants within the body and selenium, copper, iron, and zinc all function as both minerals and antioxidants.
Bipolar disorder is a chronic and debilitating mental illness characterized by severe mood swings and alternating episodes of mania and depression (NIMH, 2013, Russo, 2010). Scientists are still researching the causes of bipolar disorder, but abnormal neural activity in the brain and spinal cord is believed to be responsible for the changes in cognition and behavior (Wang et al, 2009, NIMH, 2013). Recent research utilizing brain-imaging and post-mortem brain tissue samples suggests oxidative damage to cells of the brain and spinal cord plays a strong role in the development and progression of bipolar disorder (Wang et al, 2009). Brain-imaging is used to study the brain’s structure and neural activity in patients with bipolar disorder. These studies have indicated changes in size, shape, and function of several areas of the brain including the anterior cingulate cortex and the prefrontal cortex (NIMH, 2013). Wang et al (2009), went on to test post-mortem tissue samples from the anterior cingulate cortex to determine the level of oxidative stress experienced in this region in patients with bipolar disorder. The results of this study showed a significant increase in oxidative damage in this region of the brain in patients with bipolar disorder, as well as patients with schizophrenia (Wang et al, 2009). Oxidative damage is believed to cause damage to cell membranes and DNA in the brain and neurotropic pathways, disrupting energy metabolism and neural signal transduction (Steckert et al, 2010, Wang et al, 2009).
Vitamin C serves numerous functions in the body, including antioxidant activity. Vitamin C scavenges for free radicals and donates electrons to stabilize these molecules and prevent further damage to tissues and cellular organelles (Thompson & Manore, 2009). Vitamin C works within the extracellular fluid to stabilize cellular membranes and regenerates vitamin E, another antioxidant, in the process. Vitamin C also works to synthesize DNA and neurotransmitters that may have been damaged by oxidation, further helping the bipolar patient (Thompson & Manore, 2009).
The RDA for vitamin C is 75mg for adult women and 90mg for adult men. Deficiency is uncommon in developed nations, but only a month-long deficiency of vitamin C can result in scurvy. Scurvy causes bleeding, swelling, and bone and joint pain. Untreated cases of scurvy lead to death due to infection and hemorrhaging (Medeiros, 2012). Because water-soluble vitamins are not stored in the body, toxicity from vitamin C is rare and is not considered fatal. However, megadoses of vitamin C can actually function as prooxidants, promoting oxidative damage rather than stabilizing the free radicals (Thompson & Manore, 2009). Therefore, it is important to consider all sources of vitamin C in the diet before deciding if supplementation is appropriate for an individual, with or without bipolar disorder.
Researchers agree that there is no one cause of bipolar disorder, but the new research into the role of oxidative damage offers patients new treatment options and the potential for an improved quality of life (NIMH, 2013).
Medeiros, D.M. & Wildman, R.E.C.. (2012). Advanced Human Nutrition. Jones & Bartlett Publishers. ISBN: 9780763780395.
National Institute of Mental Health. (2013). What is Bipolar Disorder?. Retrieved from http://www.nimh.nih.gov/health/topics/bipolar-disorder/index.shtml
National Institute of Standards and Technology. (2013). Online Resources for Disorders Caused by Oxidative Stress. Retrieved from http://www.oxidativestressresource.org/
Russo, A. J. (2010). Decreased Serum Hepatocyte Growth Factor (HGF) in Individuals with Bipolar Disorder Normalizes after Zinc and Anti-oxidant Therapy. Nutrition & Metabolic Insights, (3), 49-55. doi:10.4137/NMI.S5528
Steckert, A., Valvassori, S., Moretti, M., Dal-Pizzol, F., & Quevedo, J. (2010). Role of oxidative stress in the pathophysiology of bipolar disorder. Neurochemical Research, 35(9), 1295-1301. doi:10.1007/s11064-010-0195-2
Thompson, J. and Manore, M. (2009). Nutrition: An Applied Approach 2nd Edition. NY, New York: Pearson Education Inc.
Wang, JF., Shao, Li., Sun, X., and Young, L.T.. (2009). Increased oxidative stress in the anterior cingulate cortex of subjects with bipolar disorder and schizophrenia. Bipolar Disorders, 11(5), 523-529. doi:10.1111/j.1399-5618.2009.00717.x
- Bipolar disorder in Children and Teens (talkingaboutbipolar.wordpress.com)
- Common biology shared in schizophrenia and bipolar disorder (medicalxpress.com)