Non-alcoholic fatty liver disease (NAFLD), recently renamed as metabolic dysfunction-associated fatty liver disease (MAFLD), is a disease spectrum ranging from non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH).
Invasive liver biopsy remains the gold standard for diagnosing NASH through the histopathological evaluation of liver steatosis, ballooning, and lobular inflammation. However, this method has its limitations, including sample bias, low patient acceptance, and potential complications. Clinical imaging techniques such as ultrasound and magnetic resonance imaging can detect or quantify liver steatosis, but they are unable to distinguish between NASH and NAFLD. Therefore, there is a need to identify non-invasive parameters related to NASH that can serve as surrogate markers for these histological features.
In a study (https://doi.org/10.1016/j.livres.2023.11.002), published in the KeAi Journal Liver Research, a group of Chinese researchers described Sequential Molecular Ultrasound Imaging (USMI), a new strategy for identifying NASH by visualizing liver steatosis and inflammation. Notably, different microbubbles (MBs) were used to individually target CD36 and ICAM-1, rather than a dual-targeted MB. This approach allows for the differentiation of the signal source (either steatosis or inflammation) and identification of the predominant pathological change.
„As a non-invasive diagnostic tool, this strategy has the potential to support clinical treatment decisions and contribute to drug development for NASH. Furthermore, the serial testing model under various sequential USMI-based diagnostic models showed high diagnostic performance in detecting NASH with 95% sensitivity, 97% specificity, 95% positive predictive value, 97% negative predictive value, and 96% accuracy.“
Tinghui Yin, Lead author of the study
It is known that CD36 is associated with liver steatosis, while elevated ICAM-1 levels are observed during liver inflammation. Therefore, the quantitative visualization of liver CD36 and ICAM-1 can provide valuable information for determining the extent of liver steatosis and inflammation. This success brings researchers one step closer to the ultimate goal of establishing a practical non-invasive approach to detecting NASH.
Sha, T., et al. (2023). Sequential molecular ultrasound imaging for non-invasive identification and assessment of non-alcoholic steatohepatitis in mouse models. Liver Research. doi.org/10.1016/j.livres.2023.11.002.