Plasma biomarkers of oxidative stress and genetic variants in age-related macular degeneration.
OBJECTIVE
To compare plasma levels of oxidative stress biomarkers in patients with age-related macular degeneration (AMD) and controls and to evaluate a potential relationship between biochemical markers of oxidative stress and AMD susceptibility genotypes.


METHODS
Prospective case-control study.


METHODS
Plasma levels of oxidative stress biomarkers were determined in 77 AMD patients and 75 controls recruited from a clinical practice. Cysteine, cystine (CySS), glutathione, isoprostane, and isofuran were measured, and participants were genotyped for polymorphisms in the complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2) genes.


RESULTS
CySS was elevated in cases compared with controls (P = .013). After adjustment for age, sex, and smoking, this association was not significant. In all participants, CySS levels were associated with the CFH polymorphism rs3753394 (P = .028) as well as an 8-allele CFH haplotype (P = .029) after correction for age, gender, and smoking. None of the other plasma markers was related to AMD status in our cohort.


CONCLUSIONS
Our investigation of the gene-environment interaction involved in AMD revealed a relationship between a plasma biomarker of oxidative stress, CySS, and CFH genotype. These data suggest a potential association between inflammatory regulators and redox status in AMD pathogenesis.
Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, Tennessee 37232-8808, USA.
Milam A
MA
Brantley
Melissa P
MP
Osborn
Barton J
BJ
Sanders
Kasra A
KA
Rezaei
Pengcheng
P
Lu
Chun
C
Li
Ginger L
GL
Milne
Jiyang
J
Cai
Paul
P
Sternberg
D000368:Aged; D015415:Biomarkers / Q000097:blood*; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid; D017242:Complement Factor H / Q000235:genetics; D003545:Cysteine / Q000097:blood; D003553:Cystine / Q000097:blood; D005260:Female; D005663:Furans / Q000097:blood; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D005838:Genotype; D005978:Glutathione / Q000097:blood; D006801:Humans; D028421:Isoprostanes / Q000097:blood; D015227:Lipid Peroxidation; D008268:Macular Degeneration / Q000097:blood / Q000235:genetics*; D008297:Male; D018384:Oxidative Stress; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D011506:Proteins / Q000235:genetics*
C514392:ARMS2 protein, human; D015415:Biomarkers; C493495:CFH protein, human; D005663:Furans; D028421:Isoprostanes; D011506:Proteins; D003553:Cystine; D017242:Complement Factor H; D005978:Glutathione; D003545:Cysteine