Association between Serum Ferritin Levels and Metabolic-associated Fatty Liver Disease in Adults: a Cross-sectional Study Based on the NHANES.

OBJECTIVE: Ferritin, initially acting as an iron-storage protein, was found to be associated with metabolic diseases. Our study was designed to investigate the association between serum ferritin and metabolic-associated fatty liver disease (MAFLD) using data from the National Health and Nutrition Examination Survey (NHANES) of the United State of America. METHODS: A cross-sectional study was conducted, enrolling a total of 2145 participants from the NHANES in the 2017-2018 cycles. Hepatic steatosis and liver fibrosis were assessed by ultrasound images and several non-invasive indexes. Multiple regression analysis was conducted to determine the associations between serum ferritin concentration and MAFLD and liver fibrosis. RESULTS: The analysis revealed that participants with higher serum ferritin levels (Q3 and Q4 groups) had a higher prevalence of MAFLD than those with the lowest serum ferritin levels [Q3 vs. Q1: OR=2.17 (1.33, 3.53), P<0.05 in fatty liver index (FLI); Q4 vs. Q1: OR=3.13 (1.91, 5.13), P<0.05 in FLI]. Additionally, participants with the highest serum ferritin levels (Q4 group) displayed a higher prevalence of liver fibrosis [Q4 vs. Q1: OR=2.59 (1.19, 5.62), P<0.05 in liver stiffness measurement; OR=5.06 (1.12, 22.94), P<0.05 in fibrosis-4 index], with significantly increased risk observed in participants with concomitant diabetes [OR=7.45 (1.55, 35.72), P=0.012]. CONCLUSION: Our study revealed that elevated serum ferritin levels are associated with a higher prevalence of MAFLD and advanced liver fibrosis in patients. Elevated serum ferritin levels combined with diabetes are important risk factors for liver fibrosis.

Characterization of the promoter region of the bovine SIX1 gene: Roles of MyoD, PAX7, CREB and MyoG.

The SIX1 gene belongs to the family of six homeodomain transcription factors (TFs), that regulates the extracellular signal-regulated kinase 1/2 (ERK1/2) pathway and mediate skeletal muscle growth and regeneration. Previous studies have demonstrated that SIX1 is positively correlated with body measurement traits (BMTs). However, the transcriptional regulation of SIX1 remains unclear. In the present study, we determined that bovine SIX1 was highly expressed in the longissimus thoracis. To elucidate the molecular mechanisms involved in bovine SIX1 regulation, 2-kb of the 5' regulatory region were obtained. Sequence analysis identified neither a consensus TATA box nor a CCAAT box in the 5' flanking region of bovine SIX1. However, a CpG island was predicted in the region -235 to +658 relative to the transcriptional start site (TSS). An electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assay in combination with serial deletion constructs of the 5' flanking region, site-directed mutation and siRNA interference demonstrated that MyoD, PAX7 and CREB binding occur in region -689/-40 and play important roles in bovine SIX1 transcription. In addition, MyoG drives SIX1 transcription indirectly via the MEF3 motif. Taken together these interactions suggest a key functional role for SIX1 in mediating skeletal muscle growth in cattle.