Molecular signatures in the prevention of radiation damage by the synergistic effect of N-acetyl cysteine and qingre liyan decoction, a traditional chinese medicine, using a 3-dimensional cell culture model of oral mucositis.

Maria P Lambros,Ying Huang,Doreen Pon,Hari Chandana Mulamalla,Moses S S Chow,Lavanya Kondapalli,Cyrus Parsa,Robert Orlando

doi:10.1155/2015/425760

Abstract

Qingre Liyan decoction (QYD), a Traditional Chinese medicine, and N-acetyl cysteine (NAC) have been used to prevent radiation induced mucositis. This work evaluates the protective mechanisms of QYD, NAC, and their combination (NAC-QYD) at the cellular and transcriptional level. A validated organotypic model of oral mucosal consisting of a three-dimensional (3D) cell tissue-culture of primary human keratinocytes exposed to X-ray irradiation was used. Six hours after the irradiation, the tissues were evaluated by hematoxylin and eosin (H and E) and a TUNEL assay to assess histopathology and apoptosis, respectively. Total RNA was extracted and used for microarray gene expression profiling. The tissue-cultures treated with NAC-QYD preserved their integrity and showed no apoptosis. Microarray results revealed that the NAC-QYD caused the upregulation of genes encoding metallothioneins, HMOX1, and other components of the Nrf2 pathway, which protects against oxidative stress. DNA repair genes (XCP, GADD45G, RAD9, and XRCC1), protective genes (EGFR and PPARD), and genes of the NFκB pathway were upregulated. Finally, tissue-cultures treated prophylactically with NAC-QYD showed significant downregulation of apoptosis, cytokines and chemokines genes, and constrained damage-associated molecular patterns (DAMPs). NAC-QYD treatment involves the protective effect of Nrf2, NFκB, and DNA repair factors.

Highlights

Mucositis is a debilitating disease that causes ulcers in the mouths or intestines of cancer patients who are treated with radiation or chemotherapy, resulting in pain and difficulty in eating and contributing to their morbidity
We used a validated organotypic model of oral mucosal tissues consisting of a 3D cell tissue-culture of primary human keratinocytes, and we evaluated the prophylactic effects of N-acetyl cysteine (NAC), Qingre Liyan decoction (QYD), and NAC-QYD by studying the tissue histology, apoptosis, and gene expression
We found that tissues treated with NAC-QYD preserved their integrity and showed no apoptosis

Summary

Introduction

Mucositis is a debilitating disease that causes ulcers in the mouths or intestines of cancer patients who are treated with radiation or chemotherapy, resulting in pain and difficulty in eating and contributing to their morbidity. We used a validated organotypic model of oral mucosal tissues consisting of a 3D cell tissue-culture of primary human keratinocytes, and we evaluated the prophylactic effects of NAC, QYD, and NAC-QYD by studying the tissue histology, apoptosis, and gene expression. Microarrays showed that NACQYD-treated tissue had significantly upregulated metallothioneins, HMOX1, and other genes of the Nrf2 pathway, which protect cells against oxidative stress; DNA repair genes were significantly upregulated, as well as EGFR, PPARD, and genes encoding the NFκB pathway.

Results

Conclusion