The effects of vitamin C on apoptosis in HepG2 cells

Abstract

Studies in cancer research show that apoptosis plays a major role in both tumor formation and treatment response. The effects of different doses of Vitamin C, is an antioxidant, on cell proliferation and apoptosis in HepG2 cells were investigated. As an indicator of apoptosis, caspases 1, 3 and 9 enzyme activity and cytochrome c levels were determined at 31,3 mM Vitamin C concentration which reduced the cell viability significantly and at 3,13 mM and 0,313 mM Vitamin C concentrations which show significant increase of cell viability. There were no significant increase in caspases 1, 3 and 9 activity in Vitamin C treated HepG2 cells. However the caspases 3 activity decreased in HepG2 cells treated with 0,313 mM and 31,3 mM Vitamin C (53% and 57%) significantly. No statistic changes was observed in cytoplasmic and mitochondrial cytocrome c levels in HepG2 cells treated with 0,313 mM, 3,13 mM, 31,3 mM Vitamin C. In conclusion, caspases- independented cell death occurs in different doses of Vitamin C applied HepG2 cells. It may be releated to release of some apoptotic proteins from mitochondria to cytosol

Keywords

• Apoptosis
• caspase
• HepG2
• vitamin C
• cytochrome c

Vitamin C'nin HepG2 hücrelerinde apoptozis üzerine etkileri

Abstract

Kanser araştırmalarında yapılan çalışmalar, apoptozisin kanser gelişiminde ve tedaviye cevapta önemli rol oynadığını ortaya koymaktadır. Sunulan çalışmada güçlü bir antioksidan olan Vitamin C’nin farklı dozlarının hepatoselüler karsinom hücrelerindeki hücre canlılığına ve apoptotik hücre ölümüne etkileri incelenmiştir. Apoptozis belirteçlerinden, sitokrom c, kaspaz 1, kaspaz 3 ve kaspaz 9 enzim aktiviteleri hücre canlılığında azalmanın olduğu 31,3 mM Vitamin C konsantrasyonu ile hücre çoğalmasında belirgin artışın gözlendiği 0,313 mM ve 3,13 mM Vitamin C konsantrasyonlarında belirlenmiştir. Farklı dozlarda Vitamin C uygulanan HepG2 hücrelerinde kaspaz 1, 3 ve 9 enzim aktivitelerinde istatistik olarak önemli bir artış gözlenmemiştir. Ancak 0,313 mM ve 31,3 mM Vitamin C uygulanan HepG2 hücrelerinde kaspaz 3 enzim aktivitelerinde (%53 ve %57) istatistik olarak önemli azalma meydana gelmiştir. 0,313 mM, 3,13 mM, 31,3 mM konsantrasyonlarda Vitamin C uygulanan HepG2 hücrelerinin sitoplazmik ve mitokondriyal sitokrom c düzeylerinde istatistik anlamda bir değişim gözlemlenmemiştir. Sonuç olarak, farklı dozlarda Vitamin C uygulanan HepG2 hücrelerinde şekillenen hücre ölümü kaspaz bağımsız olarak şekillenmektedir. Meydana gelen hücre ölümü mitokondriden bazı apoptotik proteinlerin sitoplazmaya salınımı ile şekillenen diğer hücre ölüm yolları ile ilişkilendirilmiştir

Keywords

• Apoptozis
• HepG2
• kaspaz
• vitamin C
• sitokrom c

References

1. Arranz N, Haza AI, Garcia A, Delgado ME, Rafter J, Morales P (2008): Inhibition by vitamin C of apoptosis induced by N-nitrosamines in HepG2 and HL-60 cells, J. Appl. Toxicol.; 28, 788-796.
2. Bradford MM. (1976) A rapid and sensitive method for the quantitation of microgram quantitites of protein utilizing the principle of protein-dye binding. Analytical Biochemistry 72, 248-254.
3. Chen Q, Espey MG, Krishna MC, Mitchell JB, Corpe CP, Buettner GR, Shacter E, Levine M (2005): Pharmacologic ascorbic acid concentrations selectiveliy kill cancer cells: Actoin As a pro-drug to deliver hydrogen peroxide to tissue. Proc Natl Acad Sci USA 102, 13604- 13609.
4. Head KA (1998): Ascorbic acid in the prevention and treatment of cancer. Altern. Med. Rev. 3, 174–186.
5. Hersh D, Monack DM, Smith MR, Ghori N, Falkow S, Zychlinsky A (1999): The Salmonella invasion SipB induces macrophage apoptosis by binding to caspas-1. Proc Natl Acad Sci USA 96, 2396-401.
6. Hsieh BS, Huang LW, Su SJ, Cheng HL, Hu YC, Hung TC, Chang KL (2011). Combined arginin and ascorbic acid treatment induced apoptosis in the hepatoma cell line HA22T/VGH and changes in redox status involving the pentose phosphate pathway and reactive oxygen and nitrogen species. J Nutr Biochem 22, 234-41.
7. Hu Y, Benedict MA, Ding L, Nunez G (1999): Role of cytochrome c and dATP/ATP hydrolysis in Apaf-I- mediatcd caspase-9 activation and apoptosis, EMBO J. 18, 3586-3595.
8. Krajewski S, Krajewska M, Ellerby LM, Welsh K, Xia Z, Deveraux QL, Salvesen GS, Bredesen DE, Rosenthal RE, Fiskum G, Reed JC (1999): Release of caspase-9 from mitochondria during neuronal apoptosis and cerebral ischemia. Proc Natl Acad Sci, USA 96, 5752-5757.

9. Leung PY, Miyashita K, Young M, Tsao CS (1993): Cytotoxic effect of ascorbate and its derivatives on cultured malignant and nonmalignant cell lines. Anticancer Res 13, 475–480.
10. Miura M, Zhu H, Rotello R., Hartweig EA, Yuan J (1993): Induction of apoptosis in fibroblasts by IL-1 beta- converting enzyme, a mammalian homolog of the C. elegans cell death gene ced-3. Cell 75, 653-660.
11. Naidu KA, Karl RC, Naidu KA, Coppola D (2003): Antiproliferative and proapoptotic effect of ascorbyl stearate in human pancreatic cancer cells: association with decreased expression of insülin-like growth factor 1 receptor Digestive Disease And Science 48, 230-237.
12. Padayatty SJ, Riordan HD, Hewitt SM (2006): Intraavenously administered vitamin C as cancer therapy: Three cases. CMAJ, 174, 937-942.
13. Reynolds JA, Tanford C (1970): The gross conformation of protein-sodium dodecyl sulfate complexes. J. Biol. Chem., 245, 5161-5165.
14. Rudolf E, Rudolf K, Cervınka M (2008): Selenium activates p53 and p38 pathway and induces caspases- independent cell death in cervical cancer cells. Cell Biol Toxicol 24:123-141.
15. Salvesen GS, Dixit VM (1997) Caspases: intracellular signaling by proteolysis. Cell, 91, 443–446.
16. Shinozaki K, Hosokawa Y, Hazawa M, Kashiwakura I, Okumura K, Kaku T, Nakayama E (2011): Ascorbic acid enhances radiation-induced apoptosis in an HL60 human leukemia cell line, J Radiat Res, 52, 229–237.
17. Sinclair AJ, Barnet AH, Lunec J (1990): Free radicals and antioxidant systems in health and disease. Brj Hosp Med 43, 334-344.
18. Song HJ, Shin SH, Ross GM (2001): Oxidative stress ınduced by ascorbate causes neuronal damage in an in vivo system. Brain Res, 895, 66-72.
19. Stratton MR, Campbell PJ, Futreal A (2009): The cancer genome. Nature 458, 719–724.
20. Sümbüloğlu K, Sümbüloğlu V (2005): Biyoistatistik. Hatipoğlu yayınları:53, Ankara, 270