Connection Between Inflammation and Psychiatric Disorders May Point to Biologics as Treatment

Biologics

Inflammation and Psychiatric Disorders
Depression and other mental illnesses affect millions of people. Recent research that explores the connection between inflammation and psychiatric disorders indicates that biologic antibodies can be used to treat or even prevent psychiatric disorders.
Image Source: Flickr user Steve Snodgrass

The issues surrounding psychiatric disorders have long been swept under the rug, but the conversation about mental illness is finally opening up. From classrooms to research labs to the halls of Congress, people are searching for solutions to this public health crisis. Scientists are seeking innovative new treatment options that go beyond traditional pharmaceutical therapies by looking at possible connections between mental disorders and other biological markers. Recent studies have uncovered an association between inflammation and psychiatric disorders. Many patients who suffer from mental illness exhibit high levels of inflammation and research indicates that inflammation itself can contribute to the onset and development of mental illness. This has led some scientists to start exploring the possibility of using biologic antibodies to treat or even prevent the onset of psychiatric disorders.

Evaluating the Relationship Between Inflammation and Mental Illness

Inflammation isn’t inherently bad—it’s the body’s natural response to infection and injury—but chronic inflammation can contribute to a wide range of medical illnesses, including inflammatory bowel disease and psoriasis. Researchers have also discovered a surprising association between chronic inflammation and mental illness. Studies show that the levels of the cytokines TNF-alpha, IL-1, and IL-6 are elevated in patients with major depressive disorder, generalized anxiety disorder, post-traumatic stress disorder and anorexia nervosa.1 Patients with schizophrenia also have high levels of IL-17.2

As scientists have further explored this connection, it has become increasingly clear that inflammation can cause and contribute to the development of mental illness. Cytokine treatments for diseases like cancer and hepatitis C put patients at high risk of developing depression,3 and genetic studies associate psychiatric disorders with single nucleotide polymorphisms in immune-related genes. Other inflammatory conditions, like cardiovascular and autoimmune diseases, can also lead to mental illness.4 Scientists postulate that the association between inflammation and mental illness results from the effects of cytokines on enzymes in key signaling pathways. Pro-inflammatory cytokines, for example, activate the enzyme that degrades tryptophan, the amino acid precursor to serotonin. Chronically high cytokine levels keep this enzyme active when it shouldn’t be, which throws off the balance of serotonin in the brain5 and can lead to depression and other psychiatric disorders.

How Biologic Antibodies that Block Inflammation Can Be Used to Treat Mental Illness

Because of the strong connection between inflammation and psychiatric disorders, the search is on for potential treatments that target inflammatory pathways. One of the most promising avenues for research is the development of biologic antibodies that treat psychiatric disorders. Biologics specifically target pro-inflammatory cytokines, so they downregulate the inflammatory response. In 2013, researchers at Emory University successfully used infliximab, a biologic drug that targets TNF, to treat patients with Major Depressive Disorder. This landmark study found that in patients who suffered from depression and had high levels of inflammation, the biologic drug could relieve symptoms.6

The study at Emory was the first time a biologic drug was successfully used to treat mental illness, but it probably won’t be the last. Because of the study’s success, more researchers are trying to develop biologics that neutralize other cytokines associated with mental illness. Some researchers are also looking for biologic antibodies that block cytokine receptor proteins. The advantages of biologic antibodies over antidepressants are clear: while antidepressants often have serious side effects, biologic antibodies are highly selective for their target proteins. Off-target effects are minimal, so biologic antibody treatment would make it much easier for recovering patients to lead normal, comfortable lives.

Using Biologic Antibodies to Prevent Psychiatric Disorders

There’s no doubt that biologics present a promising treatment option, but there’s also a chance that they could be used to prevent mental illness. Studies of patients with schizophrenia indicate that cytokine levels are elevated throughout a patient’s lifetime—even before they start to show symptoms.7 The same is true for some patients with depression. Preventive treatments for people who are at risk of developing medical illnesses like cancer and heart disease are increasingly common—why not use biologics therapy to prevent psychiatric disorders?

Determining a patient’s risk wouldn’t be a problem because it’s easy to detect high levels of inflammation—in the Emory study of people with depression, researchers used a simple blood test.8 People who have high levels of inflammation in conjunction with other risk factors, such as family history and certain medical illnesses, could be treated with biologic antibodies that combat the effects of pro-inflammatory cytokines. This would dampen the inflammatory response and reduce the patient’s chance of developing a psychiatric disorder. Patients wouldn’t have to worry about side effects because of the specificity of biologic antibodies, so they would have nothing to lose with this preventive treatment. As mental illness continues to pose a major threat to public health, researchers need to find new treatment and prevention options, and biologic therapy presents an exciting possibility.

The connection between inflammation and psychiatric disorders is clear, but more research needs to be done in order to identify and develop specific therapeutics. The BIOVIA Biologics solution is innovative software that researchers can use to identify biologic antibodies that target cytokines and cytokine receptors. The software streamlines workflows by making it easy to manage data and collaborate with other researchers so that high-quality biologics can get to clinical trials as quickly as possible. Contact us today to learn more about how this software can help your lab develop cutting-edge treatments for psychiatric disorders.

  1. “Inflammatory cytokines in depression: neurobiological mechanisms and therapeutic implications,” August 29, 2013, http://www.ncbi.nlm.nih.gov/pubmed/23644052
  2. “Differential correlations between inflammatory cytokines and psychopathology in veterans with schizophrenia: Potential role for IL-17 pathway,” December 2013, http://www.schres-journal.com/article/S0920-9964(13)00565-3/abstract
  3. “Can we vaccinate against depression?” May 2012, http://www.sciencedirect.com.liboff.ohsu.edu/science/article/pii/S1359644612001225
  4. “Depression and inflammation: Examining the link,” Jun 2013, http://www.currentpsychiatry.com/home/article/depression-and-inflammation-examining-the-link/b436332438ceca4baabe8be08701d6dc.html
  5. “The common inflammatory etiology of depression and cognitive impairment: a therapeutic target,” September 2, 2014, http://jneuroinflammation.biomedcentral.com/articles/10.1186/s12974-014-0151-1
  6. “A randomized controlled trial of the tumor necrosis factor antagonist infliximab for treatment-resistant depression: the role of baseline inflammatory biomarkers,” January 2013, http://www.ncbi.nlm.nih.gov/pubmed/22945416
  7. “The Case for Adjunctive Monoclonal Antibody Immunotherapy in Schizophrenia,” February 20, 2016,
    http://www.psych.theclinics.com/article/S0193-953X(16)00004-6/abstract
  8. “Targeting inflammation to treat depression,” September 4, 2012, http://news.emory.edu/stories/2012/09/psych_miller_inflam_dep_archgenpsych/