Regulation of apoptosis by resveratrol through JAK/STAT and mitochondria mediated pathway in human epidermoid carcinoma A431 cells

https://doi.org/10.1016/j.bbrc.2008.10.158Get rights and content

Abstract

Resveratrol (trans-3,4′,5-trihydroxystilbene), a polyphenolic phytoalexin present mainly in grapes, red wine and berries, is known to possess strong chemopreventive and anticancer properties. Here, we demonstrated the anti-proliferative and apoptosis-inducing activities of resveratrol in human epidermoid carcinoma A431 cells. Resveratrol has cytotoxic effects through inhibiting cellular proliferation of A431 cells, which leads to the induction of apoptosis, as evident by an increase in the fraction of cells in the sub-G1 phase of the cell cycle and Annexin-V binding of externalized phosphatidylserine. Results revealed that inhibition of proliferation is associated with regulation of the JAK/STAT pathway, where resveratrol prevents phosphorylation of JAK, thereby inhibiting STAT1 phosphorylation. Furthermore, resveratrol treatment actively stimulated reactive oxygen species (ROS) and mitochondrial membrane depolarization. Consequently, an imbalance in the Bax/Bcl-2 ratio triggered the caspase cascade and subsequent cleavage of PARP, thereby shifting the balance in favor of apoptosis. These observations indicate that resveratrol treatment inhibits JAK/STAT-mediated gene transcription and induce the mitochondrial cell death pathway.

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Materials and methods

Chemicals. Dulbecco’s modified Eagle medium (DMEM), fetal bovine serum, antibiotic–antimycotic mixture (10,000 U/ml penicillin G, 10,000 μg/ml streptomycin sulfate, and 25 μg/ml amphoterecin B), trypsin and other chemicals of culture grade were procured from Gibco Life Sciences (India). Resveratrol (>99% pure), agarose, MTT (3-[4,5-dimethyl-2-yl]-2,5-diphenyltetrazolium bromide), dichlorodihydrofluorescein diacetate dye (DCFH-DA), rhodamine 123, propidium iodide (PI), Protease inhibitor Cocktail

Results and discussion

Preliminary screening was performed to assess the effect of resveratrol on cellular proliferation and cell viability at different time intervals using the MTT assay. There was dose- (10–150 μM) and time-dependent (24, 48, and 72 h) reductions in the viability of A431 cells treated with resveratrol (Fig. 1A). The IC50 value for growth inhibition was obtained at 40 μM treatment after 24 h incubation. Based on this observation, we selected doses (40 and 60 μM) for further mechanistic studies over a

Acknowledgments

The authors thank Dr. Ashwani Kumar (Director, Indian Institute of Toxicology Research, Lucknow) for his keen interest in the study. The authors also thank the Indian Council of Medical Research, New Delhi, for providing fellowships to Sahdeo Prasad and Jasmine George.

References (28)

  • J.M. Adams et al.

    Life or death decisions by the Bcl-2 family

    Trends Biochem. Sci.

    (2001)
  • P. Decker et al.

    Inhibition of caspase-3-mediated poly(ADP-ribose) polymerase (PARP) apoptotic cleavage by human PARP autoantibodies and effect on cells undergoing apoptosis

    J. Biol. Chem.

    (2000)
  • J. Burns et al.

    Plant foods and herbal sources of resveratrol

    J. Agric. Food Chem.

    (2002)
  • L. Le Corre et al.

    Resveratrol and breast cancer chemoprevention: molecular mechanisms

    Mol. Nutr. Food Res.

    (2005)
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