Objective To explore the regulation of peroxisome proliferator-activated receptor γ coactivator 1α( PGC-1α) and NF-E2-related factor 2( Nrf2) on expression of γ-glutamylcysteine synthetase ( γ-GCS) , and their roles in chronic obstructive pulmonary disease( COPD) . Methods Twenty-four SD rats were randomly divided into a COPD group and a normal control group. COPD model was established by intratracheal instillation of lipopolysaccharide ( LPS) and daily exposure to cigarette smog in the COPD group. The lung function was measured and the pathological changes were observed. The protein and mRNA expressions of PGC-1α, Nrf2, and γ-GCS in lung tissue were measured by immunohistochemistry, Western blot, in site hybridization ( ISH) , and reverse transcription-polymerase chain reaction ( RT-PCR ) ,respectively. Results In the COPD group, the pulmonary function ( FEV0. 3, FEV0. 3 /FVC, PEF) damage and lung pathological changes were conformed as morphological characteristics of COPD. The mRNA of PGC-1α and Nrf2 expressed in lung tissues of two group rats in the region consistent with γ-GCS mRNA. The protein and mRNA expressions of PGC-1αand γ-GCS were markedly increased in the COPD group( all P lt;0. 05) ,and the protein expression of Nrf2 was obviously up-regulated ( P lt; 0. 01) , while Nrf2 mRNA had no significant difference between the two groups( P gt;0. 05 ) . Linear correlation analysis showed that the level ofPGC-1αprotein was positively correlated with the levels of Nrf2 protein and mRNA ( r = 0. 775, 0. 515, all P lt; 0. 01) , and the levels of PGC-1αand Nrf2 protein were positively correlated with the levels of γ-GCS protein ( r = 0. 531, 0. 575, all P lt; 0. 01) and mRNA ( r = 0. 616, 0. 634, all P lt; 0. 01) . Conclusions PGC-1α, which may serve as a co-activator of Nrf2, can up-regulate the expression of γ-GCS gene cooperatively with Nrf2 through a common pathway, which might involve in the oxidative and antioxidative mechanism in the pathogenesis of COPD.
ObjectiveTo investigate the relationship between immunity related GTPase M gene (IRGM) polymorphism and pneumoconiosis susceptibility.MethodsTwo hundred and forty-eight pneumoconiosis patients were selected as a case group, 275 non-pneumoconiosis workers with similar age, sex, nationality, type of work and working age were selected as a control group. The genotypes and alleles of three single nucleotide polymorphisms (SNP) of IRGM were detected by Sanger sequencing in case group and control group. SNPstats software was used to analyze the correlation between single SNP and pneumoconiosis, and SHEsis software was used to analyze the linkage imbalance and haplotype of each locus.ResultsThe distribution frequency of IRGM rs4958846 TT genotype in the case group was higher than that of the control group. The distribution frequency of TC and CC genotype in control group was higher than that of the case group. The distribution frequency of T allele in the case group was higher than that of the control group. The distribution frequency of C allele in the control group was higher than that of the case group. All of the differences were statistical significant (P<0.05). There was no statistical significance for the distribution difference between the two groups in terms of genotype and allele at IRGM rs4958842 and rs4958843 (P>0.05). After linkage disequilibrium analysis to three gene loci at rs4958842, rs4958843 and rs4958846 of IRGM, there was linkage disequilibrium between each other gene loci (D'>0.7, r2>0.3). Haplotype analysis was conducted on three genetic loci and established four kinds of haplotypes, the frequency distribution of ACT and ACC haplotypes had statistical significances between the two groups (P<0.05), and the other haplotype had no significant correlation with the susceptibility of pneumoconiosis (P>0.05).ConclusionT allele and ACT haplotype of IRGM rs4958846 may be associated with pneumoconiosis susceptibility.