Changes in gut metabolism can contribute to how the brain processes generalized pain signals in people with fibromyalgia. These changes were detected through urinalysis, which may represent a new non-invasive strategy to diagnose and monitor these patients.
The gastrointestinal tract houses a complex and dynamic population of bacteria and other microorganisms, commonly called gut microbiome, which exert a marked influence on a person’s health and disease onset.
Analysis of small molecules derived from normal metabolism — known as metabolites — within cells, biofluids, or tissues holds promise for the identification of potential diagnostic biomarkers for several human diseases.
Metabolic imbalance has been shown to influence fibromyalgia, and studies have linked chronic pain syndrome to bacterial overgrowth within the small intestine. Fibromyalgia was also associated with changes in energy metabolism and gut metabolome — the total number of metabolites present within the gut.
Based on this, a team led by researchers from the North-West University, in South Africa, set up to analyze the urinary metabolite profile of fibromyalgia patients.
Using a technique called gas chromatography-mass spectrometry (GC-MS), the team could profile all individual components of a patient’s urine. This means that researchers were able to pinpoint which metabolites and how much of them were present in each patient’s urine.
They analyzed urine samples collected in the early morning from 18 patients with persistent fibromyalgia, as well as of 11 first-generation family members, 10 age-matched subjects without symptoms of fibromyalgia, and 41 healthy, young (age 18-22) volunteers. All study participants were women.
In total, 196 metabolites were identified by GC-MS analysis. In particular, the increased levels of 14 specific metabolites allowed the team to distinguish all control samples from those of fibromyalgia patients. These specific metabolites are commonly associated with energy metabolism, digestion and metabolism of carbohydrates — such as sugars, starches, and fibers found in foods — as well as with other host and gut metabolites.
Overall, these findings suggest that “energy utilization is a central aspect” of fibromyalgia, and that these patients may have altered bacteria population present in the gut.
This further supports the hypothesis that gut microbiome “may alter brain function through the gut-brain axis, with the gut being a gateway to generalized pain,” researchers said.
Supported by these results, the team believes that analysis of urine metabolites in fibromyalgia patients may help scientists and clinicians better understand the ever-changing basis of host-microbiome perturbations in fibromyalgia.
Moreover, such knowledge might help differentiate fibromyalgia from other common concomitant diseases, and adapt patients’ management therapy to their specific metabolic profile, they suggested.