背景:雄黄(As2S2或As4S4)是一种含砷的传统中药(TCM)。现有研究表明,长期大剂量使用具有遗传毒性。牛黄解毒(NHJD)是一种含有雄黄和其他七种中药的中药方。NHJD中的多种中药组合是否可以降低雄黄在等效剂量下引起的遗传毒性尚不清楚。
目的:基于砷甲基化代谢途径研究NHJD对雄黄遗传毒性的影响及其可能机制。
方法:六组(对照组,雄黄(0.8克/千克),NHJD(12.48克/千克),以及甘草(GU),黄芩(SB),掌叶大黄(RP)加等效剂量的雄黄,分别)设置。ICR小鼠灌胃给药12周。首先,进行了基因毒理学测试以评估NHJD的效果,GU,SB,和RP对降低雄黄的遗传毒性。无机砷(iAs),二甲基砷酸(DMA),和单甲基砷酸(MMA)通过HPLC-AFS测定,和iAs%,MMA%,DMA%,原发性甲基化指数(PMI),等。被计算。同时,S-腺苷蛋氨酸(SAM)和砷酸还原酶(ARR)水平,砷(+3)甲基转移酶(As3MT),嘌呤核苷磷酸化酶(PNP),检测谷胱甘肽S-转移omega1(GSTO1)基因表达,旨在探讨NHJD可能的缓解机制。
结果:NHJD中多个TCM的组合降低了MN‰的水平,SPA%,雄黄造成的DNA损伤,当SB,RP,和GU分别与雄黄一起使用。值得注意的是,iAs%显著下降,与仅雄黄组相比,NHJD和雄黄SB(或RP)组的DMA%和PMI显着增加(P<0.05)。观察到不同组的SAM和ARR水平增加,但只有NHJD组的ARR增加有统计学意义.此外,在NHJD组中,As3MTmRNA和GSTO1mRNA显着增加,雄黄+SB组PNPmRNA水平明显升高。
结论:这项研究表明,NHJD可以减弱雄黄的遗传毒性作用。植物药SB,RP,NHJD内的GU可能是造成这种影响的关键因素。通过增加SAM和ARR水平和升高的As3MT基因表达来增强砷甲基化能力,PNP,和GSTO1提示了这些发现背后的潜在机制。
BACKGROUND: Realgar (As2S2 or As4S4) is a traditional Chinese medicine (TCM) containing arsenic. Existing studies have shown that it has
genotoxicity under long-term use with large doses. Niuhuang Jiedu (NHJD) is a Chinese medicine prescription containing realgar and seven other TCMs. Whether the multiple TCMs combination in NHJD can reduce the
genotoxicity induced by realgar in equivalent doses is still unknown.
OBJECTIVE: To research the effect of NHJD on realgar\'s
genotoxicity and the possible mechanism involved based on the arsenic methylation metabolic pathway.
METHODS: Six groups (control, realgar (0.8 g/kg), NHJD (12.48 g/kg), as well as Glycyrrhiza uralensis Fisch (GU), Scutellaria baicalensis Georg (SB), Rheum palmatum L (RP) plus equivalent doses of realgar, respectively) were set up. ICR mice were intragastric administered for 12 weeks. First, genotoxicology tests were conducted to evaluate the effect of NHJD, GU, SB, and RP on reducing realgar\'s
genotoxicity. The inorganic arsenic (iAs), dimethyl arsenic acid (DMA), and monomethyl arsenic acid (MMA) were determined by HPLC-AFS, and the iAs%, MMA%, DMA%, primary methylation index (PMI), etc. Were calculated. Meanwhile, the S-adenosyl methionine (SAM) and arsenate reductase (ARR) levels, the arsenic (+3)methyltransferase (As3MT), purine-nucleoside phosphorylase (PNP), glutathione S-transfer omega1 (GSTO1) gene expression were detected, aimed to explore the possible alleviation mechanisms of NHJD.
RESULTS: The combination of multiple TCMs in NHJD decreased the levels of MN‰, SPA%, and DNA damage caused by realgar, with similar effects observed when SB, RP, and GU were used separately with realgar. Notably, the iAs% significantly decreased, while DMA% and PMI notably increased in the NHJD and realgar + SB (or RP) groups compared to the realgar-only group (P < 0.05). Increases in SAM and ARR levels were observed across various groups, but only the ARR increase in the NHJD group was statistically significant. Moreover, significant increases in As3MT mRNA and GSTO1 mRNA were noted in the NHJD group, and PNP mRNA levels significantly rose in the realgar + SB group.
CONCLUSIONS: This study revealed that NHJD could attenuate the genotoxic effects of realgar. The botanicals SB, RP, and GU within NHJD may be key contributors to this effect. Enhancements in arsenic methylation capabilities through increased levels of SAM and ARR and elevated gene expressions of As3MT, PNP, and GSTO1 suggest potential mechanisms behind these findings.