OBJECTIVETo investigate the effects of advanced oxidation protein products (AOPP) on epithelial-to-mesenchymal transition (EMT) in cultured human proximal tubular epithelial cells (HK-2) and explore the mechanism.

METHODSHK-2 cells treated with 50, 100, 200, and 400 µg/ml AOPP or 50 µg/m bovine serum albumin (BSA) for 24 h, or with 200 µg/ml AOPP for 0.5, 1, 3, 6, 12, and 24 h were examined for the protein expression of α-SMA and E-cadherin. In cells pretreated with diphenyleneiodonium (DPI) or cytoplasmic superoxide dismutase (C-SOD), the effects of 50 µg/ml BSA and 200 µg/ml AOPP were assessed on the expressions of α-SMA and E-cadherin, malondialdehyde (MDA) level, superoxide dismutase (SOD) activity, catalase (CAT) activity, and glutathione peroxidase (GSH-px) activity.

RESULTSAOPP treatment up-regulated α-SMA expression and down-regulated E-cadherin expression in a dose- and time-dependent fashion. AOPP exposure of the cells resulted in increased MDA level and lowered activities of SOD, CAT and GSH-PX. DPI and C-SOD partially attenuated the effects of AOPP on α-SMA, E-cadherin, MDA, SOD, CAT and GSH-px.

CONCLUSIONAOPP can induce EMT in cultured HK-2 cells via oxidative stress, and this effect can be attenuated by inhibiting the activation of NADPH oxidase and using antioxidants to delay the progression of renal interstitial fibrosis.

Actins ; metabolism ; Advanced Oxidation Protein Products ; Antioxidants ; metabolism ; Cadherins ; metabolism ; Catalase ; metabolism ; Cell Line ; Cells, Cultured ; Down-Regulation ; Epithelial Cells ; cytology ; Epithelial-Mesenchymal Transition ; Glutathione Peroxidase ; metabolism ; Humans ; Malondialdehyde ; metabolism ; NADPH Oxidases ; metabolism ; Oxidative Stress ; Superoxide Dismutase ; metabolism ; Up-Regulation

OBJECTIVETo investigate the association between single nucleotide polymorphisms (SNPs) of the transmembrane protein 39A (TMEM39A) at the loci 1880G/A, 2442T/G, and 2456A/T and systemic lupus erythematosus (SLE) in Chinese Han patients.

METHODSTMEM39A gene polymorphisms at 3 loci (1880G/A, 2442T/G, 2456 A/T) were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 110 Chinese Han patients with SLE and 80 normal control subjects, and the allele and genotype frequencies were compared by Chi-square test between the two groups.

RESULTSBoth the genotype frequencies (AA, GA and GG) and allele frequencies (A and G) at 1880G/A differed significantly between SLE cases and the normal controls (P=0.002 and P=0.044, respectively). The two groups also showed significant differences in the genotype frequencies (GG, TG and TT) (P=0.001) and allele frequencies (G and T) (P=0.041) at 2442T/G. No significant differences were found in the genotype frequencies (TT, AT and AA) or allele frequencies (T and A) at 2456A/T between the two groups (P>0.05). The allele and genotype frequencies of the 3 SNPs showed no significant differences between lupus nephritis (LN) patients and non-LN patients.

CONCLUSIONThe TMEM39A polymorphisms at 1880G/A and 2442T/G, but not at 2456 A/T gene, may be associated with the susceptibility to SLE in Chinese Han population. The genotype or allele frequencies of the 3 SNPs have no effect on the incidence of lupus nephritis.

Adult ; Alleles ; Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; Female ; Gene Frequency ; Genotype ; Humans ; Lupus Erythematosus, Systemic ; genetics ; Male ; Membrane Proteins ; genetics ; Middle Aged ; Polymorphism, Single Nucleotide ; Young Adult