Pentoxifylline attenuates cigarette smoke-induced overexpression of CXCR3 and IP-10 in mice.
- Author:
Zheng WANG
1
;
Yan-Wei CHEN
;
Jin-Nong ZHANG
;
Xiao-Fei HU
;
Mei-Jun PENG
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Cell Line; Chemokine CXCL10; genetics; metabolism; Gene Expression; drug effects; Immunohistochemistry; Male; Mice; Mice, Inbred BALB C; Pentoxifylline; pharmacology; therapeutic use; Pulmonary Emphysema; drug therapy; genetics; metabolism; Random Allocation; Receptors, CXCR3; genetics; metabolism; Reverse Transcriptase Polymerase Chain Reaction; Smoking; adverse effects
- From: Chinese Medical Journal 2012;125(11):1980-1985
- CountryChina
- Language:English
-
Abstract:
BACKGROUNDCigarette smoke-induced emphysema is associated with overexpression of the chemokine receptor CXCR3 and its ligands. Previously, we have demonstrated that pentoxifylline (PTX) alleviated cigarette smoke-induced emphysema. The aim of this study was to determine if the overexpression of CXCR3 and its ligand interferon-inducible protein-10 (IP-10) that was elicited by smoke exposure were attenuated by PTX.
METHODS(1) The study in vitro: a given number of RAW264.7 macrophages with decreasing concentrations of PTX in the culture medium were challenged with cigarette smoke extract (CSE); (2) The study in vivo: male BALB/c mice were randomized into four groups, i.e., sham-smoke, smoke only, smoke with 2 mg/kg PTX, and smoke with 10 mg/kg PTX. The smoke exposure time was 90 minutes once a day, 6 days a week for 16 weeks. PTX was given intraperitoneally before each episode of smoke exposure. Interferon (IFN)-γ and IP-10 in broncho-alveolar lavage fluid (BALF) and in culture medium were measured by enzyme-linked immunosorbent assay (ELISA). IP-10 mRNA in lung tissue was assessed by RT-PCR. CXCR3 positive cells in lung sections were visualized by immunochemistry staining.
RESULTSUp-regulation of IFN-γ and IP-10 in the culture medium of macrophages elicited by CSE was inhibited by PTX in a dose-dependent manner. Chronic cigarette smoke exposure led to overexpression of IFN-γ and IP-10 in BALF, upregulation of IP-10 mRNA and increased infiltration of CXCR3(+) cells into lung parenchyma. Administration of PTX decreased the level of IFN-γ from (6.26 ± 1.38) ng/ml to (4.43 ± 0.66) ng/ml by low dose PTX or to (1.74 ± 0.28) ng/ml by high dose PTX. IP-10 was reduced from (10.35 ± 1.49) ng/ml to (8.19 ± 0.79) ng/ml by low dose PTX or to (7.51 ± 0.60) ng/ml by high dose PTX. The expression of IP-10 mRNA was also down-regulated (P < 0.05). But only with a high dose of PTX was the ratio of CXCR3(+) cells decreased; 15.2 ± 7.3 vs. 10.4 ± 1.8 (P < 0.05).
CONCLUSIONPTX attenuates cigarette smoke-induced overexpression of chemokine receptor CXCR3 and its ligand IP-10, which is relevant to its inhibitory effect on pulmonary emphysema.
