Although the public health sector has made major efforts to avoid overnutrition, the global prevalence of obesity is still rising, and at the same time, the prevalence of non-alcoholic fatty liver disease (NAFLD) is also rising . NAFLD is an important predictor of mortality, and it is known to increase the risk of type 2 diabetes, cardiovascular disease and dyslipidemia in obese young people [2-4]. NAFLD is usually the first comorbidity of obesity. The level of liver fat content is related to the classification of metabolic diseases, which emphasizes the importance of steatosis as an early indicator of metabolic diseases. However, its underlying pathological mechanism is still unclear.
Clinically, it is necessary to characterize high-risk groups of NAFLD and take targeted measures early in life. However, reliable quantitative detection of liver fat relies on biopsy or complex imaging techniques that are only available in specialized centers [5-7]. Therefore, there is an urgent need for a reliable and simple biomarker to quantify liver fat content. Julia Lischka and others at the Medical University of Vienna published an article on Pediatr Obes, aiming to study new biomarkers of NAFLD and establish a score for predicting liver fat in severely obese youths. The results show that branched chain amino acids (BCAAs) may be an important link between obesity and other metabolic pathways. The BCAA-based metabolic score can predict the degree of steatosis in high-risk children and adolescents, and may provide a viable alternative to complex methods such as MRI or biopsy in the future .
The investigators included 68 patients with severe obesity and lipid metabolism disorders with a BMI of >97% from 9 to 19 years old. HPLC-MS included MRI-derived proton density fat fraction (MRI-PDFF), amino acids and acylcarnitines. The clinical characteristics of the patients were analyzed and determined.
The results showed that children with NAFLD had elevated BCAA levels. BCAAs are correlated with MRI-PDFF (R=0.46, P<0.01) (Figure 1).