Acidification induces Bax translocation to the mitochondria and promotes ultraviolet light-induced apoptosis

• Autorzy: Yang L , Mei Y. , Xie Q. , Han X. , Zhang F. , Gu L. , Zhang Y. , Chen Y. , Li G. , Gao Z.
• Języki publikacji: EN

Abstrakty

EN

It has been suggested that Bax translocation to the mitochondria is related to apoptosis, and that cytosol acidification contributes to apoptosis events. However, the mechanisms remain obscure. We investigated the effect of acidification on Bax translocation and on ultraviolet (UV) light-induced apoptosis. The Bax translocation assay in vitro showed that Bax translocated to the mitochondria at pH 6.5, whereas no Bax translocation was observed at pH 7.4. VHDBB cells expressing the GFP-Bax fusion protein were treated for 12 h with a pH 6.5 DMEM medium, nigericin (5 μg/ml) and UV light (50 J/cm2), separately or in combination, and Bax translocation to the mitochondria was determined by SDS-PAGE and Western blot, and apoptotic cell death was detected by flow cytometry. The results showed that some of the Bax translocated to the mitochondria in the cells treated with the normal medium, nigericin and UV in combination, whereas all of the Bax translocated to the mitochondria in the cells treated with the pH 6.5 medium, nigericin and UV in combination. In VHDBB cells treated for 12 h with nigericin, UV alone, and UV and nigericin in combination, the respective rates of apoptotic cell death were 25.08%, 33.25% and 52.88%. In cells treated with pH 6.5 medium and nigericin, pH 6.5 medium and UV, and pH 6.5 medium, nigericin and UV in combination, the respective rates of apoptotic cell death increased to 37.19%, 41.42% and 89.44%. Our results indicated that acidification induces Bax translocation from the cytosol to the mitochondria, and promotes UV lightmediated apoptosis. This suggests that there is a possibility of improving cancer treatment by combining acidification with irradiation or chemotherapeutic drugs.

Słowa kluczowe

EN

cytosol; mitochondrion; nigericin; ultraviolet light-induced apoptosis; apoptosis; Bax translocation; acidification; cancer

• Wydawca: -
• Czasopismo: Cellular and Molecular Biology Letters
• Rocznik: 2008
• Tom: 13
• Numer: 1
• Opis fizyczny: p.119-129,fig.,ref.

Twórcy

autor

Yang L

• Sun Yat-sen University, 600 Ttianhe Road, Guangzhou 510630, P.R.China

autor

Mei Y.

autor

Xie Q.

autor

Han X.

autor

Zhang F.

autor

Gu L.

autor

Zhang Y.

autor

Chen Y.

autor

Li G.

autor

Gao Z.

Bibliografia

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