Chronic Fatigue Syndrome

Symptoms of chronic fatigue syndrome (CFS), joint pain (arthritis), back pain, etc. are symptoms of extreme chronic inflammation. Recent studies of blood cells of CFS patients show patterns of gene expression consistent with systemic inflammation.

Chronic fatigue syndrome (CFS), Lyme disease, fibromyalgia, post traumatic shock, multiple chemical sensitivity (MCS), irritable bowel syndrome and many other syndromes share the same symptoms that are linked by inflammation. These symptoms may also blur into arthritis, back pain, heart disease and numerous psychological symptoms. Thus, depression is considered by some to be a symptom of inflammation. Many of the symptoms in this large group of related syndromes also respond to anti-inflammatory diets and treatments. The close association between inflammation and infection also leads to surprising responses to antibiotics. The complexity of symptoms, however, makes the labeling of the syndromes problematic. Some new technical approaches may clarify both the causes and status of these diseases.

Inflammation of tissues results from relaxation of walls of blood capillaries. This relaxation or dilation of capillaries results from the proteins and chemicals released from the cells near the capillaries. These adjacent cells have detected infecting bacteria (TLR), or responded to some type of injury or damage. The endothelial cells lining the capillaries also respond to the inflammatory signals by displaying proteins on their surfaces that snag immune cells from the blood. Thus, inflammation also results in colonization of the inflammation site with white blood cells (in contrast to the hemoglobin-containing red blood cells) that we see as pus.

The immune cells circulating in the blood and going in and out of tissues advertise the quality and quantity of inflammation by the pattern of proteins that they display on their surfaces and secrete. The presence of these inflammatory proteins in turn reflects the fact that those cells have expressed particular patterns of genes, i.e. each gene in the group was converted into messenger RNA (mRNA) that was in turn translated into protein. Gene expression can be measured either by the amount of each protein accumulated, or more conveniently by the amount of each mRNA present. The cells of each tissue are different because they express different genes and have a different mRNA population.

It is now possible to approximate the concentration and action of each cell type in a sample of blood. Viral infections produce different patterns than bacterial infections and the patterns differ at the various stages of an infection. These are observations using new technologies that are approaching a global expression fingerprint, but are still to some extent based on sorting the cells within a blood sample into groups based on their surface proteins and then analyzing the mRNAs of each group of cells.

A recent research article (below) announced the identification of unique patterns of chronic inflammatory gene expression in the blood cells of chronic fatique syndrome patients. These patterns permit both a peek into the immune processes behind CFS as well as providing an explanation of the current symptoms of the syndrome.

(Aspler AL, Bolshin C, Vernon SD, Broderick G. Evidence of Inflammatory Immune Signaling in Chronic Fatigue Syndrome: A Pilot Study of Gene Expression in Peripheral Blood. Behav Brain Funct. 2008 Sep 26;4(1):44. [Epub ahead of print] PMID: 18822143)