Iron depletion in “metabolic fatty liver syndromes”: a strong biological rationale with disappointing liver outcomes

Nonalcoholic fatty liver disease (NAFLD), its more rapidly progressive steatohepatitic variant [nonalcoholic steatohepatitis, (NASH)], and the recently defined metabolic dysfunction-associated fatty liver disease (MAFLD) may be collectively alluded to as “metabolic fatty liver syndromes” (MFLS). MFLS is a common clinical complaint for which no licensed drug treatment is available and a public health issue posing a heaven burden on healthcare systems. Iron plays a key role in many of the key pathogenic steps concurring in the development and progression of MFLS, notably including genetics, intestinal dysbiosis, adipositis, insulin resistance (IR), metaflammation, oxidative stress and ferroptosis, endoplasmic reticulum (ER) stress, and hepatic fibrosis (FIB). This notion raises the logical expectation that iron depletion, which can easily be implemented with venesection, might improve several aspects of MFLS. However, few published studies have globally failed to support these expectations. In conclusion, venesection in MFLS exhibits a strong biological rationale and possible metabolic benefits. However, confronted with failures in hepato-histological outcomes, data call for additional studies aimed to reconcile these inconsistencies.