Emphysema induced by elastase alters the mRNA relative levels from DNA repair genes in acute lung injury in response to sepsis induced by lipopolysaccharide administration in Wistar rats
EXPERIMENTAL LUNG RESEARCH
Authors: Sergio, Luiz Philippe S.; Lucinda, Leda M. F.; Reboredo, Maycon M.; de Paoli, Flavia; Fonseca, Lidia M. C.; Pinheiro, Bruno V.; Mencalha, Andre L.; Fonseca, Adenilson S.
Abstract
Purpose/Aim of the study: Patients suffering from chronic obstructive pulmonary disease (COPD) in association with acute respiratory distress syndrome (ARDS) present oxidative stress in lung cells, with production of free radicals and DNA lesions in pulmonary and adjacent cells. Once the DNA molecule is damaged, a set of enzymatic mechanisms are trigged to preserve genetic code integrity and cellular homeostasis. These enzymatic mechanisms include the base and the nucleotide excision repair pathways, as well as telomere regulation. Thus, the aim of this work was to evaluate the mRNA levels from APEX1, ERCC2, TP53, and TRF2 genes in lung tissue from Wistar rats affected by acute lung injury in response to sepsis and emphysema. Materials and Methods: Adult male Wistar rats were randomized into 4 groups (n = 6, for each group): control, emphysema, sepsis, and emphysema with sepsis. Pulmonary emphysema was induced by intratracheal instillation of elastase (12 IU/animal) and sepsis induced by intraperitoneal Escherichia coli lipopolysaccharide (LPS) injection (10 mg/kg). Lungs were removed, and samples were withdrawn for histological analysis and total RNA extraction, cDNA synthesis, and mRNA level evaluation by real time quantitative polymerase chain reaction. Results: Data show acute lung injury by LPS and emphysema by elastase and that APEX1, ERCC2, TP53, and TRF2 mRNA levels are increased significantly (p < 0.01) in emphysema with sepsis group. Conclusion: Our results suggest that alteration in mRNA levels from DNA repair and genomic stability could be part of cell response to acute lung injury in response to emphysema and sepsis.
The Relationship Between Single-Nucleotide Polymorphisms, the Expression of DNA Damage Response Genes, and Hepatocellular Carcinoma in a Polish Population
DNA AND CELL BIOLOGY
Authors: Krupa, Renata; Czarny, Piotr; Wigner, Paulina; Wozny, Joanna; Jablkowski, Maciej; Kordek, Radzislaw; Szemraj, Janusz; Sliwinski, Tomasz
Abstract
The molecular mechanism of hepatocellular carcinoma (HCC) is related to DNA damage caused by oxidative stress products induced by hepatitis B virus (HBV) or C (HCV) infection and exposure to environmental pollutants. Single-nucleotide polymorphisms (SNPs) of DNA damage response (DDR) genes may influence individual susceptibility to environmental risk factors and affect DNA repair efficacy, which, in turn, can influence the risk of HCC. The study evaluates a panel of 15 SNPs in 11 DDR genes (XRCC1, XRCC3, XPD, MUTYH, LIG1, LIG3, hOGG1, PARP1, NFIL1, FEN1, and APEX1) in 65 HCC patients, 50 HBV-and 50 HCVinfected non-cancerous patients, and 50 healthy controls. It also estimates the mRNA expression of nine DDR genes in cancerous and adjacent healthy liver tissues. Two of the investigated polymorphisms (rs1052133 and rs13181) were associated with HCC risk. For all investigated genes, the level of mRNA was significantly lower in HCC cancer tissue than in non-cancerous liver tissue. Seven of the investigated polymorphisms were statistically related to gene expression in cancer tissues. The disruption of DDR genes may be responsible for hepatocellular transformation in HCV-infected patients.