The objective of the present study was to determine the effect of different sources of dietary fibre on the oxidative stress induced by a high fat diet in laboratory rats. Thirty two laboratory rats were penned indivi...The objective of the present study was to determine the effect of different sources of dietary fibre on the oxidative stress induced by a high fat diet in laboratory rats. Thirty two laboratory rats were penned individually and divided into four groups： CONT （high fat diet）, G （70 g guar gum/kg）, P （70 g apple pectin/kg） and WB （155 g wheat bran/kg）. After 11 or 13 days of treatment DNA damage of blood leukocytes was measured by Comet assay and lipid peroxidation was studied by determining the malondialdehyde （MDA） concentration in liver and in urine. In comparison with group CONT, the degree of DNA damage was significantly lower in group WB. In groups G and P DNA damage was also reduced but not significantly. Similar results were also obtained for the liver MDA concentration. All three studied groups showed reduced liver MDA concentrations but only group WB was significant compared to group CONT. In comparison with group CONT, the groups WB and P had significantly reduced 24-hour urine MDA excretion, hut not group G. The results of the experiment confirmed that wheat bran intake effectively reduces oxidative stress induced by a high fat diet.展开更多
Peroxy radicals （ROx） concentrations were measured by Peroxy Radical Chemical Amplifier （PERCA） technique during the field campaign RISFEX 2003 （RiShifi Fall Experiment 2003）, which was performed in September 20...Peroxy radicals （ROx） concentrations were measured by Peroxy Radical Chemical Amplifier （PERCA） technique during the field campaign RISFEX 2003 （RiShifi Fall Experiment 2003）, which was performed in September 2003 at Rishiri island （45.07 N, 141.12 E, and 35 m asl） in the sea of Japan. The concentrations of nighttime ROx radicals had temporal variations around an average of 7.9±5.8 （1σ） pptv and showed a positive correlation with the summed mixing ratio of four monoterpene species. Model calculations suggested that local nighttime ROx radicals were dominated by the reactions of monoterpene with ozone （03） and nitrate radical （NO3）, contributing ca. 76% and 19%, respectively. The comparisons between the observed ROx and ones modeled had implied that the current model may be overestimated the yields of peroxy radicals from the reactions of monoterpenes with ozone and an important source of peroxy radicals was possibly missed. Abnormal high concentrations of observed ROx radicals were found during high relative humidity （RH） period （especially 〉 95%）, and the possible explanation was that the humidity correction of ROx radicals under high RH conditions may be inaccurate and overestimates ROx concen-展开更多
文摘The objective of the present study was to determine the effect of different sources of dietary fibre on the oxidative stress induced by a high fat diet in laboratory rats. Thirty two laboratory rats were penned individually and divided into four groups： CONT （high fat diet）, G （70 g guar gum/kg）, P （70 g apple pectin/kg） and WB （155 g wheat bran/kg）. After 11 or 13 days of treatment DNA damage of blood leukocytes was measured by Comet assay and lipid peroxidation was studied by determining the malondialdehyde （MDA） concentration in liver and in urine. In comparison with group CONT, the degree of DNA damage was significantly lower in group WB. In groups G and P DNA damage was also reduced but not significantly. Similar results were also obtained for the liver MDA concentration. All three studied groups showed reduced liver MDA concentrations but only group WB was significant compared to group CONT. In comparison with group CONT, the groups WB and P had significantly reduced 24-hour urine MDA excretion, hut not group G. The results of the experiment confirmed that wheat bran intake effectively reduces oxidative stress induced by a high fat diet.
基金supported by the Special Funds in Marine Public Service Project of State Oceanic Administration (201005025)National High-Tech Research and Development Plan (863) of China (2007AA092101)the International Scientific and Technological Cooperation Projects(2009DFB20610)
文摘Peroxy radicals （ROx） concentrations were measured by Peroxy Radical Chemical Amplifier （PERCA） technique during the field campaign RISFEX 2003 （RiShifi Fall Experiment 2003）, which was performed in September 2003 at Rishiri island （45.07 N, 141.12 E, and 35 m asl） in the sea of Japan. The concentrations of nighttime ROx radicals had temporal variations around an average of 7.9±5.8 （1σ） pptv and showed a positive correlation with the summed mixing ratio of four monoterpene species. Model calculations suggested that local nighttime ROx radicals were dominated by the reactions of monoterpene with ozone （03） and nitrate radical （NO3）, contributing ca. 76% and 19%, respectively. The comparisons between the observed ROx and ones modeled had implied that the current model may be overestimated the yields of peroxy radicals from the reactions of monoterpenes with ozone and an important source of peroxy radicals was possibly missed. Abnormal high concentrations of observed ROx radicals were found during high relative humidity （RH） period （especially 〉 95%）, and the possible explanation was that the humidity correction of ROx radicals under high RH conditions may be inaccurate and overestimates ROx concen-
