Antioxidant effect of haptoglobin phenotypes against DNA damage induced by hydrogen peroxide in human leukocytes.
Human haptoglobin is classified into three major phenotypes: Hp1-1, Hp2-1 and Hp2-2; there are two autosomal alleles Hp*1 and Hp*2, and the Hp*1 allele has two subtypes, Hp*1F and Hp*1S. Haptoglobin acts as an antioxidant, preventing hemoglobin-driven oxidative damage. We used the comet assay to examine oxidative damage to DNA induced by hydrogen peroxide in human leukocytes; we also looked for differences in the antioxidant capacity of haptoglobin subtypes. Haptoglobin genotypes were determined through allele-specific polymerase chain reaction, visualized on a polyacrylamide gel. The Hp1-1 genotype had the least DNA damage; this indicates that Hp alleles differ in their protective effects against oxidative damage. Among Hp*1 alleles, Hp*1F was the most protective.
Moreira
L R S
LR
Departamento de Genética e Morfologia,Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, Brazil. leonorarsm@gmail.com
Miranda-Vilela
A L
AL
Silva
I C R
IC
Akimoto
A K
AK
Klautau-Guimarães
M N
MN
Grisolia
C K
CK
D000293:Adolescent; D000328:Adult; D000975:Antioxidants; D004249:DNA Damage; D005260:Female; D006242:Haptoglobins / Q000235:genetics*; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity*; D007962:Leukocytes / Q000187:drug effects; D008297:Male; D010641:Phenotype
D000975:Antioxidants; C485359:HP protein, human; D006242:Haptoglobins; D006861:Hydrogen Peroxide