Metabolomic analysis reveals the mechanism of aluminum cytotoxicity in HT-29 cells

Leilei Yu; Jiangping Wu; Qixiao Zhai; Fengwei Tian; Jianxin Zhao; Hao Zhang; Wei Chen

doi:10.7717/peerj.7524

Metabolomic analysis reveals the mechanism of aluminum cytotoxicity in HT-29 cells

PeerJ. 2019 Aug 27:7:e7524. doi: 10.7717/peerj.7524. eCollection 2019.

Authors

Leilei Yu^{1

2

3}, Jiangping Wu^{1

3}, Qixiao Zhai^{1

2

3}, Fengwei Tian^{1

2

3}, Jianxin Zhao^{1

3

4}, Hao Zhang^{1

3

4

5}, Wei Chen^{1

3

5

6}

Affiliations

¹ School of Food Science and Technology, Jiangnan University, Wuxi, China.
² International Joint Research Laboratory for Probiotics, Jiangnan University, Wuxi, China.
³ State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.
⁴ (Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou, China.
⁵ National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, China.
⁶ Beijing Innovation Centre of Food Nutrition and Human Health, Beijing Technology & Business University, Wuxi, China.

Abstract

Background: Aluminum (Al) is toxic to animals and humans. The most common sources of human exposure to Al are food and beverages. The intestinal epithelium is the first barrier against Al-induced toxicity. In this study, HT-29, a human colon cancer cell line, was selected as an in vitro model to evaluate the Al-induced alteration in metabolomic profiles and explore the possible mechanisms of Al toxicity.

Methods: MTT assay was performed to determine the half-maximal inhibitory concentration of Al ions. Liquid chromatography-mass spectrometry (LC-MS) was used for metabolomic analysis, and its results were further confirmed using quantitative reverse transcription polymerase chain reaction (RT-qPCR) of nine selected genes.

Results: Al inhibited the growth of the HT-29 cells, and its half-maximal dose for the inhibition of cell proliferation was found to be four mM. This dose was selected for further metabolomic analysis, which revealed that 81 metabolites, such glutathione (GSH), phosphatidylcholines, phosphatidylethanolamines, and creatine, and 17 metabolic pathways, such as the tricarboxylic acid cycle, pyruvate metabolism, and GSH metabolism, were significantly altered after Al exposure. The RT-qPCR results further confirmed these findings.

Conclusion: The metabolomics and RT-qPCR results indicate that the mechanisms of Al-induced cytotoxicity in HT-29 cells include cellular apoptosis, oxidative stress, and alteration of lipid, energy, and amino acid metabolism.

Keywords: Aluminum; Cytotoxicity; HT-29 cell; Heavy metal; Metabolomic.

Grants and funding

This work was supported by the Natural Science Foundation of Jiangsu Province (BK20180603), the National Natural Science Foundation of China Key Program (31530056, 31772090, 31601452), the Postdoctoral Science Foundation of China (2018M642166), the General Financial Grant from the Jiangsu Postdoctoral Science Foundation (2018K016A), the Self-determined Research Program of Jiangnan University (JUSRP11847), the BBSRC Newton Fund Joint Centre Award, and the National first-class discipline program of Food Science and Technology (JUFSTR20180102), Collaborative innovation center of food safety and quality control in Jiangsu Province. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.