Open AccessAnti‐proliferative effect of rhein, an anthraquinone isolated from Cassia species, on Caco‐2 human adenocarcinoma cells
Author(s) -
Aviello Gabriella,
Rowland Ian,
Gill Christopher I.,
Acquaviva Angela Maria,
Capasso Francesco,
McCann Mark,
Capasso Raffaele,
Izzo Angelo A.,
Borrelli Francesca
Publication year - 2010
Publication title -
journal of cellular and molecular medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.44
H-Index - 130
eISSN - 1582-4934
pISSN - 1582-1838
DOI - 10.1111/j.1582-4934.2009.00815.x
Subject(s) - reactive oxygen species , cytotoxicity , cell growth , comet assay , dna damage , caco 2 , malondialdehyde , mapk/erk pathway , chemistry , microbiology and biotechnology , mtt assay , biology , biochemistry , kinase , oxidative stress , cell , in vitro , dna
In recent years, the use of anthraquinone laxatives, in particular senna, has been associated with damage to the intestinal epithelial layer and an increased risk of developing colorectal cancer. In this study, we evaluated the cytotoxicity of rhein, the active metabolite of senna, on human colon adenocarcinoma cells (Caco‐2) and its effect on cell proliferation. Cytotoxicity studies were performed using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT), neutral red (NR) and trans‐epithelial electrical resistance (TEER) assays whereas 3 H‐thymidine incorporation and Western blot analysis were used to evaluate the effect of rhein on cell proliferation. Moreover, for genoprotection studies Comet assay and oxidative biomarkers measurement (malondialdehyde and reactive oxygen species) were used. Rhein (0.1–10 μg/ml) had no significant cytotoxic effect on proliferating and differentiated Caco‐2 cells. Rhein (0.1 and 1 μg/ml) significantly reduced cell proliferation as well as mitogen‐activated protein (MAP) kinase activation; by contrast, at high concentration (10 μg/ml) rhein significantly increased cell proliferation and extracellular‐signal‐related kinase (ERK) phosphorylation. Moreover, rhein (0.1–10 μg/ml): ( i ) did not adversely affect the integrity of tight junctions and hence epithelial barrier function; ( ii ) did not induce DNA damage, rather it was able to reduce H 2 O 2 ‐induced DNA damage and ( iii ) significantly inhibited the increase in malondialdehyde and reactive oxygen species (ROS) levels induced by H 2 O 2 /Fe 2+ . Rhein was devoid of cytotoxic and genotoxic effects in colon adenocarcinoma cells. Moreover, at concentrations present in the colon after a human therapeutic dosage of senna, rhein inhibited cell proliferation via a mechanism that seems to involve directly the MAP kinase pathway. Finally, rhein prevents the DNA damage probably via an anti‐oxidant mechanism.