Beta-carotene protects rats against bronchitis induced by cigarette smoking.
OBJECTIVE
To investigate the protective effects of beta-carotene in rats against the development of chronic bronchitis induced by cigarette smoking.


METHODS
Forty-two Male Wistar rats were randomly divided into three study groups: (1) control (n = 15), animals underwent no treatment; (2) cigarette smoking (n = 15), animals developed chronic bronchitis through long-term cigarette smoking twice a day for 75 d; (3) beta-carotene plus cigarette smoking animals (n = 12) were given 1 ml or 15 mg/kg beta-carotene orally every day just before cigarette smoking. The levels of IL-6, IL-8, NO, superoxide dismutase (SOD) and lipoperoxide (LPO) in serum, bronchoalveolar lavage fluid (BALF) and lung tissue were measured and the pathological changes to lung tissue were analyzed using light microscopy.


RESULTS
Long-term cigarette smoking caused an obvious increase in the amount of IL-6, IL-8 and LPO and a sharp decrease in the levels of NO and SOD in smoking animals compared to controls. beta-carotene intake reversed all the changes induced by smoking and alleviated the pathological changes caused by chronic bronchitis.


CONCLUSIONS
Quantitative oral intake of beta-carotene had protective effects against chronic bronchitis induced by long-term cigarette smoking, which was associated with the increased production of NO, the clearance of some oxidative free radicals (OFR) and the alleviation of chronic inflammation.
Pang
Baosen
B
Beijing Institute of Respiratory Medicine, Beijing Chaoyang Hospita, Capital University of Medical Sciences, Beijing 100020, China.
Wang
Chen
C
Weng
Xinzhi
X
Tang
Xiaonai
X
Zhang
Hongyu
H
Niu
Shujie
S
Mao
Yanling
Y
Xin
Ping
P
Huang
Xiuxia
X
Zhang
Haiyan
H
Zhu
Jin
J
D000818:Animals; D001991:Bronchitis / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D015850:Interleukin-6 / Q000097:blood; D016209:Interleukin-8 / Q000097:blood; D008297:Male; D009569:Nitric Oxide / Q000097:blood; D051381:Rats; D017208:Rats, Wistar; D012907:Smoking / Q000009:adverse effects*; D013482:Superoxide Dismutase / Q000097:blood; D019207:beta Carotene / Q000494:pharmacology*
D015850:Interleukin-6; D016209:Interleukin-8; D019207:beta Carotene; D009569:Nitric Oxide; D013482:Superoxide Dismutase