👤 Jonathan Schug

Environmental exposure to toxic and essential metals can disrupt host immune function through mechanisms involving epigenetic, transcriptional, and post-transcriptional regulation. Although numerous studies have investigated these regulatory layers separately, integrative analyses across molecular levels in relation to metallome is missing. In this study, we performed a targeted multi-omics analysis of six immune-associated genes (NFKB1, CDKN2A, IGF2, H19, ESR1, and APOA5) and corresponding proteins in healthy residents from a long-term mining region (MRR, n = 46) and a non-mining region (NMR, n = 48). Transcriptome data were generated by mRNA sequencing, while DNA methylation data were obtained using targeted bisulfite sequencing by analyzing previously identified differentially methylated positions. Plasma protein levels were measured by enzyme-linked immunosorbent assay, and plasma metal concentrations were quantified using inductively coupled plasma mass spectrometry. We observed significantly higher plasma levels of NFKB1 and CDKN2A proteins, along with lower ESR1 transcript levels, in residents of the mining region compared to the non-mining region. NFKB1 protein levels were associated with both promoter methylation and residence in mining region, suggesting a regulatory cascade from DNA methylation to protein expression. IGF2 protein levels were higher in males and showed positive associations with age and the cumulative Z-score of essential metal mixture burden. Our results show that long-term residence in mining regions is associated with changes in NFKB1 at both the DNA methylation and protein levels, which may serve as a sensitive biomarker of metal exposure. Show less

Foxa1 and Foxa2 play both redundant and distinct roles in early pancreas development. We demonstrate here that inducible ablation of both transcription factors in mature mouse beta-cells leads to impaired glucose homeostasis and insulin secretion. The defects in both glucose-stimulated insulin secretion and intracellular calcium oscillation are more pronounced than those in beta-cells lacking only Foxa2. Unexpectedly, in contrast to the severe reduction of beta-cell-enriched factors contributing to metabolic and secretory pathways, expression of a large number of genes that are involved in neural differentiation and function is significantly elevated. We further demonstrate that expression of carbohydrate response element-binding protein (ChREBP or Mlxipl), an important transcriptional regulator of carbohydrate metabolism, is significantly affected in compound Foxa1/a2 mutant beta-cells. ChREBP expression is directly controlled by Foxa1 and Foxa2 in both the fetal endocrine pancreas as well as mature islets. These data demonstrate that Foxa1 and Foxa2 play crucial roles in the development and maintenance of beta-cell-specific secretory and metabolic pathways. Show less