Nevirapine induces apoptosis in liver (HepG2) cells.
OBJECTIVE
To generate insights into the mechanism of NVP induced hepatotoxicity.


METHODS
Liver (HepG2) cells were cultured with various concentrations of NVP. This cell line was chosen because it has low expression of cytochrome P450, allowing evaluation of the effects of NVP rather than specific metabolites. Cytotoxicity was determined using a proliferation assay and cell numbers were monitored using trypan blue exclusion assay for long term culture experiments and apoptosis induction was determined by morphological and biochemical investigation.


RESULTS
HepG2 cells treated with the highest concentration of NVP tested (819 μM) initially showed a rounded morphology and all cells had died by week three of exposure. Nuclear condensation and fragmentation, increased Annexin V/propidium iodide staining and caspase 9 activation all supported the induction of apoptosis in HepG2 cells in response to NVP treatment.


CONCLUSIONS
There is a clear induction of apoptosis in response to NVP which suggests that NVP has significant cytotoxicity, over and above any cytotoxicity of metabolites and may contribute directly to patient hepatotoxicity.
Research Institute for Health Sciences, Chiang Mai University, 110 Intavaroros Road, Sriphum, Muang District, Chiang Mai 50200, Thailand.
Jeerang
J
Wongtrakul
Molecular Pathology Laboratory, Institute of Molecular Biosciences, Mahidol University, 25/25 Phuttamonthol Sai 4, Salaya, Nakorn Pathom 73170, Thailand.
Atchara
A
Paemanee
Molecular Pathology Laboratory, Institute of Molecular Biosciences, Mahidol University, 25/25 Phuttamonthol Sai 4, Salaya, Nakorn Pathom 73170, Thailand.
Phitchayapak
P
Wintachai
Molecular Pathology Laboratory, Institute of Molecular Biosciences, Mahidol University, 25/25 Phuttamonthol Sai 4, Salaya, Nakorn Pathom 73170, Thailand.
Chutima
C
Thepparit
Proteomics Research Laboratory, Genome Institute, National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, Pathumthani 12120, Thailand.
Sittiruk
S
Roytrakul
Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, 1873 Rama 4 Road, Pathumwan, Bangkok 10330, Thailand.
Thananya
T
Thongtan
Research Institute for Health Sciences, Chiang Mai University, 110 Intavaroros Road, Sriphum, Muang District, Chiang Mai 50200, Thailand.
Kanokwan
K
Janphen
Department of Medicine, Faculty of Medicine, Chiang Mai University, 239 Huay Kaew Road, Muang District, Chiang Mai 50200, Thailand.
Khuanchai
K
Supparatpinyo
Molecular Pathology Laboratory, Institute of Molecular Biosciences, Mahidol University, 25/25 Phuttamonthol Sai 4, Salaya, Nakorn Pathom 73170, Thailand. Electronic address: duncan_r_smith@hotmail.com.
Duncan R
DR
Smith
Apoptosis; Cytotoxicity; Hepatotoxicity; Nevirapine