Preventive effect of Daiokanzoto (TJ-84) on 5-fluorouracil-induced human gingival cell death through the inhibition of reactive oxygen species production.
Daiokanzoto (TJ-84) is a traditional Japanese herbal medicine (Kampo formulation). While many Kampo formulations have been reported to regulate inflammation and immune responses in oral mucosa, there is no evidence to show that TJ-84 has beneficial effects on oral mucositis, a disease resulting from increased cell death induced by chemotherapeutic agents such as 5-fluorouracil (5-FU). In order to develop effective new therapeutic strategies for treating oral mucositis, we investigated (i) the mechanisms by which 5-FU induces the death of human gingival cells and (ii) the effects of TJ-84 on biological events induced by 5-FU. 5-FU-induced lactate dehydrogenase (LDH) release and pore formation in gingival cells (Sa3 cell line) resulted in cell death. Incubating the cells with 5-FU increased the expression of nucleotide-binding domain and leucine-rich repeat containing PYD-3 (NLRP3) and caspase-1. The cleavage of caspase-1 was observed in 5-FU-treated cells, which was followed by an increased secretion of interleukin (IL)-1β. The inhibition of the NLRP3 pathway slightly decreased the effects of 5-FU on cell viability and LDH release, suggesting that NLRP3 may be in part involved in 5-FU-induced cell death. TJ-84 decreased 5-FU-induced LDH release and cell death and also significantly inhibited the depolarization of mitochondria and the up-regulation of 5-FU-induced reactive oxygen species (ROS) and nitric oxide (NO) production. The transcriptional factor, nuclear factor-κB (NF-κB) was not involved in the 5-FU-induced cell death in Sa3 cells. In conclusion, we provide evidence suggesting that the increase of ROS production in mitochondria, rather than NLRP3 activation, was considered to be associated with the cell death induced by 5-FU. The results also suggested that TJ-84 may attenuate 5-FU-induced cell death through the inhibition of mitochondrial ROS production.
Department of Oral Healthcare Education, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan.
Kaya
K
Yoshida
Department of Oral Health Science and Social Welfare, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan.
Masami
M
Yoshioka
Department of Histology and Oral Histology, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan.
Hirohiko
H
Okamura
Department of Hygiene and Oral Health Science, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan.
Satomi
S
Moriyama
Department of Clinical Pharmacy, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan.
Kazuyoshi
K
Kawazoe
Oral Ecology Research Group, Faculty of Dentistry, Laval University, Quebec City, QC, Canada.
Daniel
D
Grenier
Department of Hygiene and Oral Health Science, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan.
Daisuke
D
Hinode
D020170:Caspase 1 / Q000378:metabolism; D016923:Cell Death / Q000187:drug effects* / Q000502:physiology; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D005472:Fluorouracil / Q000494:pharmacology*; D005881:Gingiva / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D020835:Medicine, Kampo; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013280:Stomatitis / Q000139:chemically induced / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology
D004365:Drugs, Chinese Herbal; D017382:Reactive Oxygen Species; D020170:Caspase 1; D005472:Fluorouracil