[Effects of chronic intermittent hypoxia on oxidative stress and inflammatory response and the interventional roles of adiponectin].

OBJECTIVE:To explore the effects of chronic intermittent hypoxia (CIH) on oxidative stress and inflammatory response and the interventional roles of adiponectin (Ad). METHODS:A total of 45 male Wistar rats were randomly divided into three groups of control group, CIH and CIH+Ad (n = 15 each). The control group breathed room air while the CIH and CIH+Ad groups received CIH 8 h/d for 5 successive weeks. The CIH+Ad group Ad had an injection of 10 µg once a week through tail vein. At the end of experiment (Day 35), comparison was performed among three groups about Ad, tumor necrosis factor α (TNF-α), C-reactive protein (CRP) and interleukin (IL) 6 from serum as well as malondialdehyde, superoxide dismutase (SOD), myeloperoxidase (MPO), reactive oxygen spieces (ROS) and nuclear factor (NF) κB from genioglossus. RESULTS:Serum Ad level in CIH group was lower than those in control and CIH+Ad groups ((4 208 ± 2 239) vs (7 051 ± 2 432) and (6 405 ± 2 384) ng/ml, all P < 0.05) with no statistic difference between control and CIH+Ad groups. Both serum levels of TNF-α and CRP were higher in CIH group than those in control and CIH+Ad groups ((70.87 ± 35.16) vs (26.54 ± 20.32) and (29.50 ± 22.54) pg/ml, as well as (31.84 ± 11.48) vs (22.68 ± 9.63), (25.32 ± 8.34) mg/L, all P < 0.05)with no significant difference between control and CIH+Ad groups. Serum IL-6 levels were all higher in CIH group and CIH+Ad group than that in control group ((30.54 ± 12.25) and (23.04 ± 13.) vs (14.10 ± 8.83) pg/ml, all P < 0.05) with no significant difference between CIH and CIH+Ad groups. Genioglossal malondialdehyde level was significantly elevated in CIH group than those in control and CIH+Ad groups ((8.05 ± 4.53) vs (5.18 ± 3.03) and ((5.74 ± 3.06) nmol/mg, all P < 0.01) with no significant difference between control and CIH+Ad groups. Genioglossal SOD activity was lower in CIH+Ad group than that in CIH group but higher than that in control group ((42.42 ± 23.17) vs (61.77 ± 36.38) and (18.62 ± 11.67) U/mg, all P < 0.05). Genioglossal MPO levels were significantly higher in both CIH and CIH+Ad groups than that in control group ((0.40 ± 0.29) and (0.31 ± 0.17) vs (0.17 ± 0.08) µU/mg, all P < 0.01), with no significance between CIH and CIH+Ad groups. The relative level of total reactive oxygen species (ROS) in genioglossus of CIH+Ad group was significantly lower than that in CIH group but higher than that in control group (1.94 ± 1.01 vs 3.31 ± 1.56 and 1.08 ± 0.38 all P < 0.05). The transcription of NF-κB was significantly higher in CIH group than that in control and CIH+Ad groups (2.24 ± 0.34 vs 0.78 ± 0.21, P < 0.05), but there was no statistical difference with CIH+Ad group (1.04 ± 0.27). CONCLUSION:CIH may induce oxidative stress and inflammation possibly through NF κB pathway while a supplement of Ad attenuates the above CIH-induced responses.