Journal of Life Science (생명과학회지)

Korean Society of Life Science (한국생명과학회)
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Effects of Cholic Acid/CDCA and FGF-19 on the Protein Levels of the Endogenous Small Heterodimer Partner (SHP) in the Mouse Liver and HepG2 Cells

생쥐의 간과 HepG2 세포에 있어서 내인성 small heterodimer partner (SHP)의 단백질 수준에 미치는 cholic acid/CDCA 및 FGF-19의 효과

  • Min, Gye-Sik (Department of Pharmaceutical Engineering, Jinju National University)
  • 민계식 (진주산업대학교 제약공학과)
  • Published : 2009.12.30
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Abstract

Recent studies determined that a chronic western-style diet increased the endogenous small heterodimer partner (SHP) protein levels in mice. In experiments with cell cultures, chenodeoxy cholic acid (CDCA) treatment increased endogenous SHP protein levels and reduced the degradation rate of exogenously expressed flag-SHP levels in the human hepatoma cell line, HepG2 cells. In addition, bile acid-induced intestinal fibroblast growth factor-19 (FGF-19) increased the half-life of the exogenously expressed SHP when HepG2 cells were transfected with ad-flag-SHP. However, both the expression level and the degradation rate of the endogenous SHP in response to cholic acid and FGF-19 have not been well understood, either in mice or in cultured HepG2 cells. This study examined the effects of cholic acid treatment on the endogenous SHP protein levels in mice and the effects of FGF-19 on the degradation rate of the endogenous SHP protein in HepG2 cells. Mice fed 0.5% cholic acid in normal chow showed an increase in endogenous SHP protein levels during both 12 hr and 24 hr treatment periods as compared to control mice fed only normal chow. In cultured HepG2 cells, treatment with CDCA did not noticeably change the rate of degradation in the endogenous SHP protein from cells not treated with CDCA. Although consistent with the previous studies on the exogenous ad-flag-SHP protein, treatment with FGF-19 significantly decreased the degradation rate of the endogenous SHP protein when HepG2 cells were treated with cyclohexamide. These results suggest that both bile acids and FGF-19 increase the endogenous SHP protein levels in mouse liver and HepG2 cells.

최근의 연구에서 생쥐에 장기간 서구식 사료를 급여했을 때 내인성 SHP 단백질의 수준이 증가함을 보고하였다. 또한 HepG2 세포배양을 통한 실험에서, CDCA 처리가 내인성 SHP 단백질의 수준을 증가시킬 뿐만 아니라 외인성으로 발현된 flag-SHP의 분해율을 감소시켰다. 그리고 HepG2 세포를 ad-flag-SHP로 유전자 형질전환 시켰을 때, 담즙산에 의해 유도되어진 소장 FGF-19이 외인성으로 발현된 flag-SHP 단백질의 반감기를 증가시켰다. 그러나 cholic acid와 FGF-19에 의한 내인성 SHP 단백질의 발현수준과 분해율은 생쥐 또는 배양된 간암세포주에서 아직 명확히 이해되고 있지 않다. 이 연구는 cholic acid의 처리가 생쥐에서 내인성 SHP 단백질의 수준에 미치는 영향과, FGF-19이 HepG2 세포주에서 내인성 SHP 단백질의 분해율에 미치는 영향을 조사하였다. 정상적인 사료를 급여한 대조군 생쥐에서의 내인성 SHP 단백질 수준과 비교하여, 0.5%의 cholic acid를 첨가한 사료를 급여한 생쥐에서는 12시간과 24시간의 처리기간 동안에 내인성 SHP 단백질의 수준이 증가하였다. 배양된 인간 간암세포주인 HepG2에서 CDCA의 처리는 CDCA를 처리하지 않은 대조군 세포주와 비교하여 내인성 SHP 단백질의 분해율을 유의성 있게 변화시키지 않았다. 한편 외인성 ad-flag-SHP 단백질에 대한 이전의 연구와 일치하게, HepG2 세포에 cyclohexamide를 처리하였을 때 FGF-19는 내인성 SHP 단백질의 분해율을 현저히 감소시켰다. 이러한 결과는 담즙산과 FGF-19 모두 생쥐의 간과 HepG2 세포주에서 내인성 SHP 단백질의 수준을 증가시킴을 제시한다.

Keywords

References

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