Figure 6.

Metabolism of ¹³C-ketoisocaproic acid (KICA) as a breath biomarker of mitochondrial function. This study was conducted on 39 (20 lean and 19 obese) hypertransaminasemic patients with histologically-proven NAFLD ranging from simple steatosis (NASH 0-I) to severe steatohepatitis and fibrosis (NASH II-IV). Control subjects were 20 lean and 8 overweight healthy individuals. Compared with healthy subjects and patients with simple steatosis, NASH patients had enhanced methacetin demethylation (p = 0.001), but ketoisocaproate decarboxylation was mildly or greatly decreased and delayed in simple steatosis and steatohepatitis, respectively. Ketoisocaproate decarboxylation was impaired further in obese patients with NASH, but not in patients with simple steatosis and in overweight controls. Symbols (*, #) indicate significant differences compared to the controls (0.006 < p <0.001). From Portincasa et al. [147].