Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071, China; Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071, China.
Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071, China.
Toxicology. 2014 Jul 3;321:53-61. doi: 10.1016/j.tox.2014.03.011. Epub 2014 Apr 6.
Prenatal caffeine ingestion is one of the risk factors for intrauterine growth retardation (IUGR). Adrenal plays a pivotal role, mainly through steroidogenesis, in the regulation of intrauterine homeostasis and in fetal development and maturation. We have shown that prenatal caffeine ingestion can inhibit fetal adrenal corticosterone production, but the underlying mechanism is unknown. This study investigated the effects of prenatal caffeine ingestion on corticosterone and its associated synthesized enzymes (steroidogenic acute regulatory protein, StAR; 3β-hydroxysteroid dehydrogenase, 3β-HSD; cytochrome P450 cholesterol side chain cleavage, P450scc; P450c21; and P450c11) in the fetal adrenal in rats and further explored the underlying mechanism by analyzing the epigenetic modification and expression of the key transcription factor steroidogenic factor-1 (SF-1). The pregnant rats were intragastrically treated with 120 mg/kg.d caffeine from gestational day 11-20. The results showed that the IUGR rate was 51.2% after caffeine treatment. The contents of corticosterone and the mRNA levels of StAR, P450scc, P450c21, and P450c11 were decreased significantly in the fetal adrenal. Furthermore, caffeine reduced both the protein and the mRNA expression of SF-1 in the fetal adrenal. The epigenetic analysis showed that caffeine treatment can significantly enhance the mRNA expression of DNA methyltransferase (Dnmt) 1, Dnmt3a, histone deacetylases (Hdac) 1, and Hdac2. The detection of DNA methylation by bisulfite-sequencing PCR uncovered a notably increased total methylation rate in the SF-1 promoter. The ChIP assay showed decreased acetylation levels of H3K9 and H3K14 in the SF-1 promoter. In conclusion, prenatal caffeine ingestion is able to induce aberrant DNA methylation and histone acetylation of the SF-1 promoter in the rat fetal adrenal. These effects may contribute to the inhibition of the expression of SF-1 and its associated steroidogenic enzymes and the production of corticosterone during fetal development.
产前咖啡因摄入是宫内生长迟缓（IUGR）的危险因素之一。肾上腺在调节宫内平衡和胎儿发育成熟中起着关键作用，主要通过类固醇生成。我们已经表明，产前咖啡因摄入可以抑制胎儿肾上腺皮质酮的产生，但潜在的机制尚不清楚。本研究探讨了产前咖啡因摄入对大鼠胎儿肾上腺皮质酮及其相关合成酶（类固醇急性调节蛋白，StAR；3β-羟类固醇脱氢酶，3β-HSD；细胞色素 P450 胆固醇侧链裂解酶，P450scc；P450c21；和 P450c11）的影响，并通过分析关键转录因子类固醇生成因子-1（SF-1）的表观遗传修饰和表达，进一步探讨了潜在的机制。从妊娠第 11-20 天，给怀孕的老鼠灌胃 120mg/kg.d 的咖啡因。结果表明，咖啡因处理后 IUGR 率为 51.2%。胎儿肾上腺皮质酮含量和 StAR、P450scc、P450c21 和 P450c11 的 mRNA 水平显著降低。此外，咖啡因降低了胎儿肾上腺中的 SF-1 蛋白和 mRNA 表达。表观遗传分析表明，咖啡因处理可显著增加 DNA 甲基转移酶（Dnmt）1、Dnmt3a、组蛋白去乙酰化酶（Hdac）1 和 Hdac2 的 mRNA 表达。亚硫酸氢盐测序 PCR 检测到 SF-1 启动子的总甲基化率显著增加。ChIP 检测显示 SF-1 启动子上 H3K9 和 H3K14 的乙酰化水平降低。总之，产前咖啡因摄入可导致大鼠胎儿肾上腺 SF-1 启动子异常的 DNA 甲基化和组蛋白乙酰化。这些影响可能导致 SF-1 及其相关的类固醇生成酶的表达受到抑制，并导致胎儿发育过程中皮质酮的产生减少。
