You may remember the classic Nash Rambler automobile. But you have probably never heard of the stealthy medical condition NASH (non-alcoholic steatohepatitis). NASH is a deadly form of non-alcoholic fatty liver disease (NAFLD), a disease marked by excessive buildup of fat in the liver, and which affects almost 25% of the US population. NASH goes beyond liver fat, however, to the active destruction of liver cells and thus, liver functions.
It may be surprising that such a destructive disease can actually be very hard to detect. The challenge, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDKD), is that NASH often presents few symptoms (fatigue or some discomfort in the liver area) or even none, despite the onset of cirrhosis. The current gold standard for NASH diagnosis is a biopsy, a procedure that is both unpleasant and a bit dangerous for the unlucky patient. However, there are alternatives on the horizon, including proteomics.
To determine if measuring proteins circulating in blood could serve as a non-invasive alternative to liver biopsies, researchers used our technology to analyze serum samples from 577 participants in a study on NAFLD and obesity (Wood et al., 2017). They compared the protein data to results from genetic analysis and phenomic analysis (i.e., levels of glucose, insulin, high-density lipoproteins, triglyceride, alanine aminotransferase, ferratin, creatinine, chloride, zinc, drug/hormone usage, sleep apnea diagnosis) and concluded that the use of genomic data to assess liver health was a smidge better than flipping a coin (not a surprise). Phenomic data were better predictors than genomic data, but proteomic data really shined. Adding the phenomic and genomic findings to the proteomic data only marginally improved the results given by the proteomic data alone.
These findings were confirmed in a study published late last year, in which researchers used the SomaScan® technology to look at a range of health-related conditions (including liver fat), (Williams et al., 2019). These data, which are also providing new information about the biology of NAFLD/NASH and new avenues for treatment, strongly suggest that protein measurements alone can be an effective – and maybe even preferred – method of detecting NASH presence early enough to take corrective action.
Williams, S. A., Kivimaki, M., Langenberg, C., Hingorani, A. D., Casas, J. P., Bouchard, C., . . . Wareham, N. J. (2019). Plasma protein patterns as comprehensive indicators of health. Nature Medicine. doi:10.1038/s41591-019-0665-2
Wood, G. C., Chu, X., Argyropoulos, G., Benotti, P., Rolston, D., Mirshahi, T., . . . Gerhard, G. S. (2017). A multi-component classifier for nonalcoholic fatty liver disease (NAFLD) based on genomic, proteomic, and phenomic data domains. Sci Rep, 7, 43238. doi:10.1038/srep43238