[Effects of vitamin E and ω-3 fatty acids on protecting ambient PM_(2. 5)-induced cardiovascular injury].

OBJECTIVE: To observe whether vitamin E( Ve) and ω-3 polyunsaturated fatty acids( ω-3 FA) could prevent the fine particulate matter( PM_(2. 5))-induced cardiovascular injury and explore the potential mechanism.

METHODS: The SD rats were assigned randomly to 8 groups, those were control group, PM_(2. 5)group, Ve treatment groups( 3, 10, 30 mg/( kg·d)) and ω-3 FA treatment groups( 10, 30 and 90 mg/( kg·d)). The rats were pretreated with different concentration of Ve and ω-3 FA separately for 14 days, then were exposed to ambient PM_(2. 5) by intratracheal instillation( 10 mg/kg BW). All the rats were sacrificed after the last PM_(2. 5) exposure, then the arterial blood, lungs and cardiac tissues were collected. The expressions of tumor necrosis factor-α( TNF-α), interleukin-1β( IL-1β), interleukin-6( IL-6) in serum, bronchoalveolar lavage fluid and supernatant of cardiac tissue were detected by ELISA kits. The levels of malondialdehyde( MDA), superoxide dismutase( SOD) and glutathione-peroxidase( GSH-Px) in serum and myocardium were also measured.

RESULTS: Compared with the severe injury of rats in PM_(2. 5) exposure group, the rats in Ve or ω-3 FA groups had a slighter injury in lung and cardiac tissue with the increase of Ve and ω-3 FA. Similarly, the levels of IL-1β, IL-6 in bronchoalveolar lavage fluid had a decreasing trend with the increase of Ve and ω-3 FA compared with the PM_(2. 5) exposure groups. Meanwhile, the expressions of TNF-α in Ve and ω-3 FA high dose groups were significantly reduced when compared with the PM_(2. 5) exposure group( P <0. 05). In addition, the MDA levels in serum were markedly decreased and the activities of SOD were significantly increased compared with the PM_(2. 5)exposure group( P < 0. 05 or P < 0. 01) whereas the SOD activities were elevated only in the ω-3 FA high dose groups( P < 0. 05). Meanwhile, the levels of IL-6 and TNF-α in serum had an obvious decrease compared with the PM_(2. 5) exposure group( P < 0. 01). Similarly, compared with the PM_(2. 5)exposure group, the expressions of MDA were markedly decreased and the activities of SOD and GSH-Px in myocardium were significantly increased( P < 0. 05 or P < 0. 01) in the Ve treatment group. In addition, the activities of GSH-Px was found higher only in the ω-3 FA high treatment group compared with the PM_(2. 5)exposure group( P < 0. 05). Meanwhile, the levels of IL-1β and TNF-α in cardiac tissue had an obvious decrease trend with the increase of Ve and ω-3 FA.

CONCLUSION: PM_(2. 5) exposure may increase inflammatory response and oxidative stress, supplementation with Ve and ω-3 FA could prevent the PM_(2. 5)-induced inflammatory reaction and oxidative stress damage by increasing the activities of SOD and GSH-Px.