Polymorphisms and functional activity in superoxide dismutase and catalase genes in smokers with COPD

Abstract

Increased oxidative stress has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). This study investigated the risk of COPD and the substitution of alanine 16 with valine (Ala16Val) polymorphism of manganese-superoxide dismutase (Mn-SOD) and the cytosine to thymidine transition of nucleotide -262 (-262C.T) polymorphism of the catalase gene, and the activity of erythrocyte SOD and catalase.The subjects were stable COPD patient ever smokers (n5165) and healthy controls, matched for age and cigarette consumption. Genotyping of Mn-SOD at Ala16Val and the catalase gene at -262C.T was performed, and the functional activity of SOD and catalase in erythrocytes determined.There were no significant differences in the distribution of the different genotypes or allele frequencies between patients and controls for both the Mn-SOD and catalase genes. Among healthy controls or COPD patients, no differences were observed in erythrocyte SOD and catalase activity, irrespective of genotype. Significantly higher erythrocyte catalase activity was found in COPD patients than in healthy controls. The T/T catalase genotype and Ala/Ala Mn-SOD genotype were uncommon in the present Chinese population.The increase in erythrocyte catalase activity in Chinese patients with chronic obstructive pulmonary disease probably indicates dysfunction of the oxidant/antioxidant defence system, but it is unclear whether this increase is compensatory or a pathogenic factor.

Altered antioxidant enzyme activity with severity and comorbidities of chronic obstructive pulmonary disease (COPD) in South Indian population

“…Consistent with our result, a study in erythrocyte red blood cells showed decreased CAT activity in patients with COPD [35,36]. In contrast, a study on single nucleotide polymorphism in CAT gene (-262 C > T) showed that erythrocyte catalase activity was higher in COPD patients with the C/C genotype, and with the combined C/T and T/T genotypes, than in healthy controls [37]. Our study supports the finding of Tavilani et al, which reported an increase in SOD and CAT activities in alveolar macrophages of elderly smokers [38].…”

“…However, we found a dramatic increase in SOD and CAT activities among patients with more severe COPD. It was found that erythrocyte SOD and CAT activities gradually increased from GOLD stages I to IV in COPD patients, which is supported by previous reports [36][37][38][39][40][41]. Indeed, various studies [40][41][42] except one study [7] have suggested that certain markers of oxidative stress may be related to tobacco smoking or to the severity of COPD.…”

Superoxide dismutases, lung function and bronchial responsiveness in a general population

“…An association of the Ala16Val SNP was not found neither with the presence of COPD nor with lung function decline, which is in concordance with results of two previous studies performed [18,19].…”

“…Ala16Val, which is localised in a protein signal sequence, and thus possibly has a functional role [12][13][14]. This substitution has been associated with a higher lung cancer risk in Caucasians [15][16][17] but not with the presence of COPD in Caucasian and Chinese smokers [18,19]. SOD3 contains three nonsynonymous SNPs, i.e.…”

Gene Polymorphisms of Tumor Necrosis Factor Alpha and Antioxidant Enzymes in Bronchial Asthma

“…Various inflammatory and structural cells in the airways have been reported to generate increased amounts of ROS [2]. The lungs have developed several endogenous antioxidant systems to deal with the production of free radicals [3]. Superoxide dismutase (SOD) catalyses the dismutation of O 2 ⋅ -to H 2 O 2 and oxygen (O 2 ), while catalase (CAT) decomposes H 2 O 2 to water and oxygen.…”