Benzophenone-3 (BP-3), a widely used ultraviolet absorber in various scenarios, exhibits estrogenic toxicity at environmental concentrations—as demonstrated in our prior work. Given the importance of hepatic metabolism and the limitations of previous hepatotoxicity research (high-dose models, lack of mammalian data, etc.), we evaluated BP-3’s hepatic effects on postpartum mice at environmentally relevant levels. Postpartum mice were exposed to BP-3 via drinking water from postpartum day 1 (PPD1) to PPD35. Groups solvent control (0.001% DMSO), 10–1000 nM BP-3, and diethylstilbestrol (DES) were established. Basic growth performance, histopathological changes, and a range of molecular indicators were assessed. The results showed that BP-3 exposure induced dose-dependent increases in liver weight, histopathological alterations (sinusoidal dilation, hepatocyte edema, and necrosis), and significant upregulation of oxidative stress markers (Ros, Mda), chemokines (Ccl27a/b), and inflammatory factors (Tnf-α, Il-6, Nf-κb) at the mRNA level (all p < 0.05). Conversely, levels of antioxidant enzymes (Cat, Sod1/2) and anti-inflammatory factor Ho-1 were markedly decreased (p < 0.05). A clear dose-effect relationship was confirmed using the Integrated Biomarker Response (IBR) framework. This pioneering study establishes the hepatotoxicity of environmentally relevant BP-3 levels in mammals and offers methodological insights for endocrine disruptor assessment.

The male reproductive impairment caused by environmental estrogens (EEs) stands as a pivotal research area in environmental toxicology. Alpha2-macroglobulin (A2M) emerges as a promising molecule capable of counteracting oxidative stress induced by EEs. This study conducted exposure experiments spanning PND1 to PND56 employing ICR mice, aiming to delve into the expression patterns of A2M and its modulated IL-6 in the testicular tissue of mice subsequent to diethylstilbestrol (DES) and benzophenone (BP) exposure, while elucidating the pivotal role of ERs in this intricate process. Our findings revealed that upon DES exposure (10 and 100 nM), there was a pronounced upregulation of A2M (mRNA and in situ protein levels) in mouse testicular tissue. Similarly, exposure to BPs (BP-1, BP-2, and BP-3, each at 10 and 1000 nM) exhibited comparable effects and increasing A2M levels in serum. Notably, BP exposure also caused an elevation in IL-6 levels (which could be directly regulated by A2M) within testicular tissue (mRNA and in situ protein). Remarkably, the specific estrogen receptor antagonist ICI 182780 (0.5 mg/kg/day) was effective in reversing the upregulation of both A2M and IL-6 induced by BP exposure. Significantly, the results of theoretical prediction of the potential ERE site in the A2m gene promoter region and ChIP-qPCR experiment provide essential and strong evidence for the key conclusion that A2m is the target gene of ER. Taken together, our study highlights EEs’ ability to regulate A2M expression in the male reproductive system via the ER signaling pathway. This vital insight deepens our understanding of molecular mechanisms protecting against oxidative stress caused by EEs.