a Department of Pathobiology, Faculty of Science, Mahidol University;
b Department of Physiology, Faculty of Pharmacy, Mahidol University;
c Department of Pharmacology, Faculty of Dentistry, Mahidol University;
d Department of Anesthesiology, Sapporo Medical University School of Medicine, Sapporo, Japan
e Department of Neurosurgery, Yame Public General Hospital, 540-2 Takatsuka, Yame 834-0034, Japan
f Department of Laboratory and Vascular Medicine, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima, Japan
g Department of Parasitology and Entomology, Faculty of Public Health, Mahidol University;
h Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
Received 30 August 2011, Accepted 15 September 2011
Abstract
Environmental tobacco smoke (ETS) exposure is linked to carcinogenic, oxidative and inflammatory cellular reactions. Green tea polyphenol reportedly plays a role in the prevention of inflammation-related diseases. To evaluate the effects of green tea extract (GTE) on cellular location of High Mobility Group Box-1 (HMGB1) protein, we studied the lung tissue in rats exposed to cigarette smoke (CS). Rats were divided into three groups; CS, CSG, and C, which were groups of CS-treated only, CS-treated with GTE dietary supplement, and the control, respectively. Our findings by immunocytochemistry showed that abundant HMGB1 translocated from the nucleus to the cytoplasm in the lung tissues of rats that were exposed to CS, whereas HMGB1 was localized to the nuclei of CSG and C group. For in vitro studies, cotinine stimulated the secretion of HMGB1 in a dose and time dependent manner and the HMGB1 level was suppressed by GTE in murine macrophage cell lines. Our results could suggest that GTE supplementation which could suppress HMGB1 may offer a beneficial effect against diseases.
Keywords: Green tea; HMGB1; Environmental tobacco smoke (ETS), Nuclear translocation
* corresponding author : Dr. Salunya Tancharoen