Inhibitory effects of heavy metals on CYP1A expression in eel hepatocyte cultures

뱀장어 배양 간세포에서의 Cytochrome P4501A (CYP1A) 유전자 발현에 대한 중금속들의 억제효과

  • Kwon, Hyuk-Chu (Department of Aquatic Life Medical Science, Sun Moon University) ;
  • Maeng, Joon-Ho (Department of Aquatic Life Medical Science, Sun Moon University) ;
  • Choi, Seong-Hee (Department of Food Science, Sun Moon University)
  • 권혁추 (선문대학교 수산생명의학과) ;
  • 맹준호 (선문대학교 수산생명의학과) ;
  • 최성희 (선문대학교 식품과학과)
  • Received : 2010.06.18
  • Accepted : 2010.08.20
  • Published : 2010.08.30

Abstract

Effects of heavy metal ions on the gene expression of cytochrome P4501A (CYP1A) were examined in cultured eel hepatocytes. When the expression of CYP1A mRNA was measured by RT-PCR after incubation of eel hepatocytes with benzo[$\alpha$]pyrene (B[$\alpha$]P) at concentrations of 10-8~10-5 M, the CYP1A expression increased with B[$\alpha$]P treatment in a dose dependent manner, showing significant increase at concentrations more than 10-7 M. When the eel hepatocyte was treated with cadmium (10-6 and 10-5 M), the expression of CYP1A was inhibited and especially at higher concentration (10-5 M). The inhibition of CYP1A expression by cadmium was also observed in cells treated with B[$\alpha$]P. In another study, effects of heavy metal ions on the expression of CYP1A were examined in cultured hepatocytes isolated from eel which was treated previously with B[$\alpha$]P in vivo. Hepatocytes isolated from the liver of eel taken at 48 hours after injection of B[$\alpha$]P (10 mg/kg) were cultured for 2 days with cadmium, copper, lead or zinc (10-6 and 10-5 M). The expression of CYP1A was found to be suppressed by the metal ions compared with the control in which CYP1A was induced with previous treatment of B[$\alpha$]P in vivo. The present results may provide an important basic information for studying the effects of heavy metal ions on CYP1A expression in other species of fish and studying toxicological mechanisms of heavy metal ions in aquatic livings.

뱀장어 간세포 배양을 이용하여 cytochrome P4501A (CYP1A) 유전자 발현에 대한 중금속들의 영향에 대해 조사하였다. 첫째, CYP1A mRNA 발현에 대한 benzo[$\alpha$]pyrene (B[a]P)의 농도별 조사에서, B[$\alpha$]P $10^{-8}\sim10^{-5}$ M의 농도로 배양액에 첨가하여 배양한 후 세포를 수거하여 RT-PCR 방법으로 CYP1A mRNA 발현량을 조사하였다. CYP1A mRNA 발현은 B[$\alpha$농도 의존적으로 유도되었으며, $10^{-7}$ M 농도부터 통계적으로 유의차를 나타냈다 (p<0.05). 둘째로 뱀장어 간세포에 B[a]P ($10^{-5}$ M)와 카드뮴 ($10^{-6}$, $10^{-5}$ M)을 각각 또는 함께 첨가하여 CYP1A mRNA 발현을 조사하였다. 카드뮴을 첨가한 그룹은 vehicle에 비해 CYP1A 발현의 억제가 관찰되었으며, 고농도($10^{-5}$M)의 카드뮴에서 더 많이 억제되었다. 또한 B[$\alpha$]P와 카드뮴을 함께 처리한 그룹에서도 CYP1A 유전자 발현은 B[$\alpha$]P 단독 처리에 비해 현저한 억제가 관찰되었다. 셋째로, in vivo에서 B[a]P를 주사한 뱀장어의 배양 간세포를 이용하여 CYP1A 유전자 발현에 대한 중금속들의 영향을 조사하였는데, 뱀장어에 10mg/kg의 B[$\alpha$]P를 주사한 후, 48시간 후에 간을 채취하여 간세포 배양을 하였다. 카드뮴, 구리, 납 및 아연 ($10^{-6}$, $10^{-5}$ M) 등을 각각 배양액에 첨가하여 2일간 배양한 후 CYP1A mRNA 발현량을 조사하였다. 이미 B[$\alpha$]P 처리에 의해 CYP1A 발현이 유도된 대조구 (vehicle)에 비해 중금속들이 첨가된 모든 그룹에서 CYP1A 유전자 발현 억제가 관찰되었다. 본 연구는 여러 어종에서 CYP1A 유전자 발현에 대한 중금속들의 영향 및 중금속 독성을 연구하는데 매우 중요한 기초 자료로 활용되어질 것이다.

Keywords

References

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