Restraining reactive oxygen species in Listeria monocytogenes promotes the apoptosis of glial cells.
OBJECTIVE
Listeria monocytogenes is a facultative anaerobic foodborne pathogen that can traverse the blood-brain barrier and cause brain infection. L. monocytogenes infection induces host cell apoptosis in several cell types. In this study, we investigated the apoptosis of human glioma cell line U251 invaded by L. monocytogenes and evaluated the function of bacterial reactive oxygen species (ROS) during infection.


METHODS
Bacterial ROS level was reduced by carrying out treatment with N-acetyl cysteine (NAC) and diphenyleneiodonium chloride (DPI). After infection, the apoptosis of U251 cells was examined by flow cytometry assay and propidium iodide staining.


RESULTS
DPI and NAC efficiently decreased ROS level in L. monocytogenes without affecting bacterial growth. Moreover, the apoptosis of glial cells was enhanced upon invasion of DPI- and NAC-pretreated L. monocytogenes.


CONCLUSIONS
Results indicate that the apoptosis of glial cells can be induced by L. monocytogenes, and that the inhibition of bacterial ROS increases the apoptosis of host cells.
a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China.
Sen
S
Li
a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China.
Yixuan
Y
Li
a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China.
Guowei
G
Chen
b Certification and Review Center, Shanghai Municipal Food and Drug, Administration , Shanghai 200020 , China.
Jingchen
J
Zhang
a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China.
Fei
F
Xu
a School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology , 516 Jungong Road, Shanghai 200093 , China.
Man
M
Wu
D000111:Acetylcysteine / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D045744:Cell Line, Tumor; D006801:Humans; D008089:Listeria monocytogenes / Q000378:metabolism* / Q000502:physiology; D009457:Neuroglia / Q000166:cytology* / Q000378:metabolism*; D009861:Onium Compounds / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism*
D009861:Onium Compounds; D017382:Reactive Oxygen Species; C007517:diphenyleneiodonium; D000111:Acetylcysteine
Apoptosis; Glial cells; Listeria monocytogenes; Reactive oxygen species