Microbiome/transforming growth factor-β axis as a diagnostic and therapeutic target for MASLD in Egyptian patients

Abstract Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as the leading cause of chronic hepatic disorders worldwide. Gut microbiome dysbiosis influences MASLD pathogenesis via the gut–liver axis. This study investigated gut microbiome alterations, biochemical markers, and their diagnostic potential in MASLD. A case control study included 60 Egyptian adults (30 MASLD patients, 30 healthy controls) who underwent comprehensive biochemical profiling and quantitative real-time polymerase chain reaction (qRT-PCR) analysis of selected gut microbiota from fecal samples. Antioxidant biomarkers, including superoxide dismutase (SOD) and malondialdehyde (MDA), were measured spectrophotometrically, while mRNA expression of nuclear factor erythroid 2-related factor 2 (NRF2), transforming growth factor-beta (TGF-β), and signal transducer and activator of transcription 3 (STAT3) was assessed by reverse transcription PCR (RT-PCR). The fibrosis index (FIB-4) was calculated, and diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curves. MASLD patients displayed marked microbiome dysbiosis, with significant enrichment of Bacteroides (p < 0.001) and depletion of Bifidobacterium (p < 0.005). TGF-β expression was significantly elevated (p < 0.001) and demonstrated excellent diagnostic performance (area under the curve [AUC] = 0.956; sensitivity = 100%; specificity = 83.3%). MDA, FIB-4, and NRF2 showed moderate accuracy, while Bacteroides (AUC = 0.744) and Bifidobacterium (AUC = 0.683) also provided discriminatory value. Bacteroides correlated positively with total cholesterol, whereas Bifidobacterium correlated inversely. Collectively, elevated TGF-β, increased Bacteroides, and reduced Bifidobacterium highlight promising diagnostic and therapeutic targets in MASLD. These findings emphasize the mechanistic role of the gut–liver axis and support microbiome-informed roles for early detection and management.