Characterising biochemical changes to hepatocellular carcinoma (HepG2) cells upon exposure to green tea extract using untargeted metabolomics

Morrison, Natasha Louise (2019) Characterising biochemical changes to hepatocellular carcinoma (HepG2) cells upon exposure to green tea extract using untargeted metabolomics. Honours thesis, Murdoch University.

Abstract

Complementary and alternative medicines (CAMs) have become the preferred medicine for many in replacement of conventional medicines due to cultural or financial reasons. Herbal CAMS, in particular, have become a popular choice of medicine for their purported health benefits. Green tea extract (GTE) contains the major catechins epigallocatechin-3-gallate, epicatechin gallate, epigallocatechin and epicatechin, all of which vary across different GTE products and have become the focus on research into its purported health benefits. However, there have been cases of GTE-induced hepatotoxicity, for which the biochemical pathways have not been characterised. This study elucidates compounds similarities and changes in catechin levels within several different GTE products, and biochemical pathways related to reactive oxygen species (ROS) production affected by acute GTE supplementation in an in vitro setting using metabolomic techniques. It was found that GTE hepatotoxicity significantly decreased amino acids, oxoacids and carboxylic acids at 1 mg/mL exposure but produced a different metabolite profile upon 0.1 mg/mL exposure. The results demonstrate that GTE hepatotoxicity is a dose-dependent process that induces ROS production, ATP depletion and apoptosis, which corroborates prior knowledge on this topic. These results utilise a novel field of research, metabolomics, to add insight into the biochemical mechanisms of GTE hepatotoxicity and to observe the mass spectral pattern and levels of four catechins in different GTE products: (+)-catechin, (-)-epicatechin, (-)-epigallocatechin and (-)-epigallocatechin-3-gallate. This will allow consumers to become more aware of herb-induced liver injury and provide data to aid the regulation of herbal CAMs.

Item Type:	Thesis (Honours)
Murdoch Affiliation(s):	Medical, Molecular and Forensic Sciences
Supervisor(s):	Maker, Garth and Trengove, Robert
URI:	http://researchrepository.murdoch.edu.au/id/eprint/53997

Item Control Page

Downloads