Aflatoxins are liver carcinogens and are common contaminants in unpackaged peanut (UPP) oil. However, the health risks associated with consuming aflatoxins in UPP oil remain unclear. In this study, aflatoxin contamination in 143 UPP oil samples from Guangdong Province were assessed via liquid chromatography–tandem mass spectrometry (LC-MS). We also recruited 168 human subjects, who consumed this oil, to measure their liver functions and lipid metabolism status. Aflatoxin B1 (AFB1) was detected in 79.72% of the UPP oil samples, with levels ranging from 0.02 to 174.13 μg/kg. The average daily human intake of AFB1 from UPP oil was 3.14 ng/kg·bw/day; therefore, the incidence of liver cancer, caused by intake of 1 ng/kg·bw/day AFB1, was estimated to be 5.32 cases out of every 100,000 persons per year. Meanwhile, Hepatitis B virus (HBV) infection and AFB1 exposure exerted a synergistic effect to cause liver dysfunction. In addition, the triglycerides (TG) abnormal rate was statistically significant when using AFB1 to estimate daily intake (EDI) quartile spacing grouping (p = 0.011). In conclusion, high aflatoxin exposure may exacerbate the harmful effects of HBV infection on liver function. Contamination of UPP oil with aflatoxins in Guangdong urgently requires more attention, and public health management of the consumer population is urgently required.

Aflatoxin B1 (AFB1), a well-established hepatic carcinogen, has limited research on early-stage epigenetic biomarkers for aflatoxin-induced liver damage. In this study, we investigated 168 unpackaged peanut oil (UPP) consumers to evaluate associations among AFB1 exposure, HBV infection, RUNX3 methylation, and liver function. Our findings indicated an average daily AFB1 intake of 3.14 ng/kg·bw/day from UPP oil consumption. The high AFB1 exposure group exhibited significantly elevated gamma-glutamyl transferase (GGT) levels compared with the low AFB1 exposure group (p = 0.030). AFB1 exposure was negatively correlated with methylation status at the 2nd, 8th, and 9th CpG sites of RUNX3 (r_s = −0.196, −0.192, −0.181, p = 0.021, 0.024, 0.036). Furthermore, methylation at the 8th and 9th CpG sites positively correlated with GGT (r_s = 0.206, 0.203, p = 0.019, 0.024). HBV infection significantly influenced RUNX3 methylation, with the HBsAg⁺ group exhibiting 16.25% lower methylation (p < 0.05). Stratified analysis by HBV and AFB1 revealed that in the low AFB1 exposure subgroup, RUNX3 methylation in the HBsAg⁺ group exhibited a significant 26.38% reduction compared with the HBsAg⁻ group. These results indicated that AFB1 and HBV independently and synergistically promote site-specific RUNX3 hypomethylation. Our results implicated RUNX3 methylation as a critical mediator in HBV-AFB1 co-exposure hepatotoxicity, potentially serving as a novel epigenetic biomarker for early liver damage detection.

Ultraviolet radiation (UVR) exposure accelerates skin aging by disrupting cellular homeostasis and inducing epigenetic changes, such as promoter hypermethylation of key regulatory genes. However, the molecular mechanisms underlying UVR-driven epigenetic silencing remain poorly understood. By integrating high-throughput DNA methylation profiling with co-regulatory network analysis, we identified KIT as a hub gene in a photoaging-associated methylation module. Pathway enrichment further revealed coordinated hypermethylation of the canonical Wnt/β-catenin signaling pathway, establishing the Wnt/KIT axis as a critical epigenetic-signaling nexus in UVR-induced skin fibroblast aging. In immortalized human skin fibroblasts (HSFs), UVR suppressed Wnt signaling, leading to KIT promoter hypermethylation, transcriptional silencing, and premature photoaging. Gain-of-function studies revealed that reversing KIT hypermethylation either via Wnt pathway activation or KIT overexpression effectively mitigated photoaging-associated phenotypes. Crucially, we found that puerarin (PUE), a natural isoflavone, reversed UVR-induced epigenetic silencing by directly interacting with β-catenin, reactivating Wnt signaling, and restoring KIT expression. PUE treatment preserved cellular function in UVR-damaged fibroblasts. These findings establish the Wnt/β-catenin-KIT axis as a critical epigenetic driver of skin aging and highlight puerarin as a promising therapeutic candidate for targeted anti-aging intervention.