SPP1 and metabolic dysfunction-associated steatotic liver disease: Y. Yilmaz et al. reported similar results, demonstrating a correlation between serum OPN concentrations and serum aminotransferase levels (aspartate aminotransferase: β = 0.295, p < 0.01; alanine aminotransferase: β = 0.285, p < 0.01) in patients with MASLD.