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pH-Dependent Effects of L-Cysteine on Mercury Dissolution of α-HgS and β-HgS

Biological Trace Element Research volume 185, pages509–512(2018)Cite this article

Abstract

Mercury sulfide is an insoluble inorganic mercury compound, and it is the main chemical form in traditional oral mercury-containing medicines. Hg2+ has a high affinity for thiols, and small molecule thiols in the gastrointestinal tract may promote mercury dissolution of mercury sulfide by binding to Hg2+. L-cysteine is the only amino acid that possesses a reducing sulfhydryl group (-SH), out of the 20 amino acids. This study investigates the effect of L-cysteine on mercury dissolution of mercury sulfide at pHs ranging from 1.2 to 7.2. The results showed that L-cysteine had different pH-dependent effects on the mercury dissolution of α-HgS and β-HgS. For α-HgS, the dissolved mercury concentration increased from 5.47 ± 0.97 ng/mL to 12.49 ± 0.54 ng/mL when the pH rose from 1.2 to 4.2, and decreased to 3.37 ± 0.70 ng/mL at pH 6.0 and then increased to 9.36 ± 0.79 ng/mL at pH 7.2. For β-HgS, the dissolved mercury concentration increased from 151.09 ± 2.25 ng/mL to 2346.71 ± 62.62 ng/mL when the pH increased from 1.2 to 7.2. In conclusion, L-Cys was distinctly enhanced upon mercury dissolution of α-HgS and β-HgS with increasing pH. These results may contribute to our understanding of the mercury absorption mechanism of traditional oral mercury-containing medicines.

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References

  1. 1.

    Clarkson TW, Magos L (2006) The toxicology of mercury and its chemical compounds. Crit Rev Toxicol 36(8):609–662. https://doi.org/10.1080/10408440600845619

    Article  PubMed  CAS  Google Scholar 

  2. 2.

    Park J, Zheng W (2012) Human exposure and health effects of inorganic and elemental mercury. J Prev Med Public Heal 45(6):344–352. https://doi.org/10.3961/jpmph.2012.45.6.344

    Article  Google Scholar 

  3. 3.

    Reeder RJ, Schoonen M, Lanzirotti A (2006) Metal speciation and its role in bioaccessibility and bioavailability. Rev Mineral Geochemistry 64:59–113

    Article  CAS  Google Scholar 

  4. 4.

    Chen CJ, Wu SK, Wang YB, Hou JF, Ma L, Sun XY (2012) Recent researches of synthetic mercury sulfide in traditional medicine system. China J Chin Mater Med 37:2968–2970

    CAS  Google Scholar 

  5. 5.

    Zhao XY, Sun M, Wang JX, Xu YZ, Liu Y, Zhang ZF, Lu LY (2013) Characterization of Tibetan medicine Zuota by multiple techniques. Bioinorg Chem Appl Article ID:198545, 1–198545,11

  6. 6.

    Li C, Zhan D, Leng-ben-cai-rang, Sang-lao, Suo-lang, Duo-jie-la-dan, Duo-ji, Du YZ, Li LS, Zhang M, Yang HX, Bi HT, Wei LX (2015) Chemical components, mercury coordination structure and micro-morphology of Tibetan medicine Zuotai. Spectrosc Spect Anal 35:1072–1078

    CAS  Google Scholar 

  7. 7.

    Meng QZ (1988) Inorganic chemistry. Beijing Normal University Press, Beijing

    Google Scholar 

  8. 8.

    Zheng ZY, Li C, Zhang M, Yang HX, Geng LJ, Li LS, Du YZ, Wei LX (2015) Dissolution, absorption and bioaccumulation in gastrointestinal tract of mercury in HgS-containing traditional medicines Cinnabar and Zuotai. China J Chin Mater Med 40:2455–2460

    CAS  Google Scholar 

  9. 9.

    Zhang GY, Wang DP, Li C, Zhu HM, Wei LX, Du YZ (2012) Experimental study on long-term accumulation of mercury after oral administrate of Tibetan medicine Zuotai. Lishizhen Med Mater Medica Res 23:2146–2147

    CAS  Google Scholar 

  10. 10.

    Tian XZ, He HY, Liu J, Wu Q, Shi JZ (2015) The absorption distribution and excretion of mercury in cinnabar and cinnabar-containing remedy. Lishizhen Med Mater Medica Res 26:1106–1108

    CAS  Google Scholar 

  11. 11.

    Liang AH, Li CY, Xue YB, Wang JH, Zhao Y, Liu T, Cao CY, Yi Y, Hao R (2009) Study of mercury cumulation in Cinnabar-treated rats. China J Chin Mater Med 34:3068–3072

    Google Scholar 

  12. 12.

    Bridges CC, Zalups RK (2010) Transport of inorganic mercury and methylmercury in target tissues and organs. J Toxicol Environ Health B Crit Rev 13(5):385–410. https://doi.org/10.1080/10937401003673750

    Article  PubMed  CAS  Google Scholar 

  13. 13.

    Stipanuk MH (2004) Sulfur amino acid metabolism: pathways for production and removal of homocysteine and cysteine. Rev Lit Arts Am 24:72–81

    Google Scholar 

  14. 14.

    US Pharmacopoeia, the National Formulary. (2012) Solutions. Second Supplement to USP 35-NF 30: 5773–5774

  15. 15.

    Wei SY, Zhu YL, Liang XY, Li L, Chen P (2012) Determination of the content of mercury and analysis of the influencing factors on the dissolution of cinnabar in digestive juice. Chin J Hos Phar 32:494–496

    CAS  Google Scholar 

  16. 16.

    Morgano MA, Milani RF, Perrone AAM (2015) Determination of total mercury in sushi samples employing direct mercury analyzer. Food Anal Methods 8(9):2301–2307. https://doi.org/10.1007/s12161-015-0117-7

    Article  Google Scholar 

  17. 17.

    Li C, Suolang Z, Wangzhang, Du YZ, Wei LX (2011) Chemical and structural analysis of Nengchi Bakuang ashes in refining of Tibetan medicine Zuotai. Chinese J Pharm Anal 31:2220–2224

    CAS  Google Scholar 

  18. 18.

    Li C, Duoji, Zhandui, Xia ZJ, Du YZ, Wei LX (2013) Chemical and structural analysis of Nengchi Bajin ashes in refining of Tibetan medicine gTSothal. China J Chin Mater Med 37:1952–1957

    CAS  Google Scholar 

  19. 19.

    Jalilehvand F, Leung BO, Izadifard M, Damian E (2006) Mercury(II) cysteine complexes in alkaline aqueous solution. Inorg Chem 45(1):66–73. https://doi.org/10.1021/ic0508932

    Article  PubMed  CAS  Google Scholar 

  20. 20.

    Berger LI, Frenkel M, Koh CA, Bradley PE, Fuhr JR, Koppenol WH, Bruno TJ (2014) CRC handbook of chemistry and physics, 95th edn. CRC press, Boca Raton

    Google Scholar 

  21. 21.

    Zeng KW, Wang Q, Yang XD, Wang K (2007) Investigation on dissolution of cinnabar In vitro. China J Chin Mater Med 32:231–234

    CAS  Google Scholar 

  22. 22.

    Zhou XR, Zeng KW, Wang Q, Yang XD, Wang K (2010) In vitro studies on dissolved substance of cinnabar: chemical species and biological properties. J Ethnopharmacol 131(1):196–202. https://doi.org/10.1016/j.jep.2010.06.018

    Article  PubMed  CAS  Google Scholar 

  23. 23.

    Zhou XR, Wang LM, Sun XM, Yang XW, Chen CY, Wang Q, Yang XD (2011) Cinnabar is not converted into methylmercury by human intestinal bacteria. J Ethnopharmacol 135(1):110–115. https://doi.org/10.1016/j.jep.2011.02.032

    Article  PubMed  CAS  Google Scholar 

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Funding

This work was funded by the National Natural Science Foundation of China (81374063), the Key Laboratory Special Development Program of Qinghai Province (2017-ZJ-Y08), the Qinghai Provincial Key Laboratory of Tibetan Medicine Pharmacology and Safety Evaluation, and “The Dawn of West China” 2014 Talent Training Program of the Chinese Academy of Sciences.

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Affiliations

  1. Northwest Institute of Plateau Biology, Qinghai Provincial Key Laboratory of Tibetan Medicine Pharmacology and Safety Evaluation, Chinese Academy of Sciences, Xin-ning Road 23, Xi-ning, Qinghai, China
    • Ming Zhang
    • , Hongtao Bi
    • , Cen Li
    • , Yuzhi Du
    •  & Lixin Wei
  2. Key Laboratory of Tibetan Medicine Research, Chinese Academy of Sciences, Xining, 810008, China
    • Ming Zhang
    • , Hongtao Bi
    • , Cen Li
    • , Yuzhi Du
    •  & Lixin Wei
  3. University of Chinese Academic of Sciences, Beijing, 100049, China
    • Ming Zhang
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  1. Ming Zhang
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Correspondence to Hongtao Bi or Lixin Wei.

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Zhang, M., Bi, H., Li, C. et al. pH-Dependent Effects of L-Cysteine on Mercury Dissolution of α-HgS and β-HgS. Biol Trace Elem Res 185, 509–512 (2018). https://doi.org/10.1007/s12011-018-1254-9

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Keywords

  • Mercury sulfide
  • L-cysteine
  • Mercury dissolution
  • pH-dependent effects