RNA sequencing supports distinct reactive oxygen species-mediated pathways of apoptosis by high and low size mass fractions of Bay leaf (Lauris nobilis) in HT-29 cells

Annabelle L. Rodd; Katherine Ververis; Dheeshana Sayakkarage; Abdul W. Khan; Haloom Rafehi; Mark Ziemann; Shanon J. Loveridge; Ross Lazarus; Caroline Kerr; Trevor Lockett; Assam El-Osta; Tom C. Karagiannis; Louise E. Bennett

doi:10.1039/C5FO00467E

RNA sequencing supports distinct reactive oxygen species-mediated pathways of apoptosis by high and low size mass fractions of Bay leaf (Lauris nobilis) in HT-29 cells

Annabelle L. Rodd,^ab Katherine Ververis,^ab Dheeshana Sayakkarage,^a Abdul W. Khan,^c Haloom Rafehi,^abc Mark Ziemann,^c Shanon J. Loveridge,^a Ross Lazarus,^d Caroline Kerr,^e Trevor Lockett,^e Assam El-Osta,^bcfg Tom C. Karagiannis*^ab and Louise E. Bennett*^h

Author affiliations

* Corresponding authors

^a Epigenomic Medicine, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria, Australia

^b Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia

^c Epigenetics in Human Health and Disease, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria, Australia

^d Medical Bioinformatics, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria, Australia

^e CSIRO Food and Nutrition Flagship, North Ryde, New South Wales, Australia

^f Epigenomic Profiling Facility, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct, Melbourne, Victoria, Australia

^g Department of Medicine, Monash University, Melbourne, Victoria, Australia

^h CSIRO Food and Nutrition Flagship, Werribee, Victoria, Australia
E-mail: louise.bennett@csiro.au
Fax: +616 9731 3201
Tel: +616 9731 3200

Abstract

Anti-proliferative and pro-apoptotic effects of Bay leaf (Laurus nobilis) in mammalian cancer and HT-29 adenocarcinoma cells have been previously attributed to effects of polyphenolic and essential oil chemical species. Recently, we demonstrated differentiated growth-regulating effects of high (HFBL) versus low molecular mass (LFBL) aqueous fractions of bay leaf and now confirm by comparative effects on gene expression, that HFBL and LFBL suppress HT-29 growth by distinct mechanisms. Induction of intra-cellular lesions including DNA strand breakage by extra-cellular HFBL, invoked the hypothesis that iron-mediated reactive oxygen species with capacity to penetrate cell membrane, were responsible for HFBL-mediated effects, supported by equivalent effects of HFBL in combination with γ radiation. Activities of HFBL and LFBL were interpreted to reflect differentiated responses to iron-mediated reactive oxygen species (ROS), occurring either outside or inside cells. In the presence of LFBL, apoptotic death was relatively delayed compared with HFBL. ROS production by LFBL mediated p53-dependent apoptosis and recovery was suppressed by promoting G₁/S phase arrest and failure of cellular tight junctions. In comparison, intra-cellular anti-oxidant protection exerted by LFBL was absent for extra-cellular HFBL (likely polysaccharide-rich), which potentiated more rapid apoptosis by producing DNA double strand breaks. Differentiated effects on expression of genes regulating ROS defense and chromatic condensation by LFBL versus HFBL, were observed. The results support ferrous iron in cell culture systems and potentially in vivo, can invoke different extra-cellular versus intra-cellular ROS-mediated chemistries, that may be regulated by exogenous, including dietary species.

$Graphical abstract: RNA sequencing supports distinct reactive oxygen species-mediated pathways of apoptosis by high and low size mass fractions of Bay leaf (Lauris nobilis) in HT-29 cells$

Food & Function

RNA sequencing supports distinct reactive oxygen species-mediated pathways of apoptosis by high and low size mass fractions of Bay leaf (Lauris nobilis) in HT-29 cells

Abstract

Article information

Download Citation

Permissions

RNA sequencing supports distinct reactive oxygen species-mediated pathways of apoptosis by high and low size mass fractions of Bay leaf (Lauris nobilis) in HT-29 cells

Social activity

Search articles by author

Spotlight

Advertisements