Advances in metabolomics are providing insights into psoriasis beyond what can be gleaned from genetic or immunologic studies.
In one recent development in this emerging field, investigators defined a unique serum profile of psoriasis based on specific metabolites. Building on those results, they developed some advanced statistical models that suggest metabolomics might one day be promising for the diagnosis, monitoring, and treatment of patients with this disease.
Results of the study, which were published recently in the Archives of Dermatological Research,1 show that individuals with psoriasis exhibit significantly different serum concentrations of specific amino acids, urea, acylcarnitines, phosphatidylcholines, phytol, and other metabolites compared with control subjects.
“While dermatologists are already doing an excellent job, understanding the metabolomics and biochemical background of psoriasis will definitely improve the treatment of their patients,” says investigator Aigar Ottas, M.Sc., chair of medical biochemistry with the Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia.
To date, most scientific investigations of psoriasis have been focused on the genetic background or immunologic aspects of the disease. What Mr. Ottas and other researchers like him hope to do is foster a broader understanding of the disease through metabolomics, an emerging field that focuses on the identification and measurement of metabolites such as amino acids, carbohydrates and carbohydrate derivatives, and lipids.
“Although the understanding of the genetic background of a disease is very important, it does not allow to monitor the current state of a disease nor its progression,” Mr. Ottas tells Dermatology Times. “This is something that metabolomics could really contribute in.”
Metabolites make up unique psoriasis profile
To help define a metabolomic profile for psoriasis, Mr. Ottas collected fasting blood samples from a total of 55 psoriasis patients and 51 age- and sex-matched controls.
In one portion of the study, they used a targeted approach to analyze concentrations of known metabolites. A total of 19 metabolites were identified that differed significantly between psoriasis patients and controls. For example, serum from psoriasis patients had lower concentrations of acylcarnitines, such as nonaylcarnitine (0.4 +/- 0.01 µM vs 0.5 +/- 0.01 µM; P = 0.002), and had higher concentrations of amino acids such as glutamate (92.85 +/- 66.43 µM vs 49.06 +/- 22.76 µM; P = 0.002), phenylalanine (82.91 +/- 18.96 µM vs 72.46 +/- 13.51 µM; P = 0.026), and ornithine (99.79 +/- 29.44 µM vs 82.28 +/- 20.85 µM; P = 0.011).
In a second portion of the study, investigators used an untargeted approach to discover other metabolites that might be implicated in psoriasis. They found a total of 22 metabolites with concentrations that varied significantly between serum of psoriasis patients and controls; of these, 12 metabolites could be identified; these included urea, taurine, and phytol, among others.
Many of the metabolites identified in the study are either part of the urea cycle or very closely related. Other metabolites had an exogenous (ie, food) origin.
“Since the metabolism of psoriasis patients seems to be altered it might be worth investigating if and how much diet affects the onset and progression of the disease,” Mr. Ottas says.