The role of quinazoline in ameliorating intervertebral disc degeneration by inhibiting oxidative stress and anti-inflammation via NF-κB/MAPKs signaling pathway.

OBJECTIVE: Previous studies have shown that Quinazoline (QNZ) plays extremely important roles in the cellular physiological activity, but it has been rarely examined on cell behavior following intervertebral disc degeneration (IVDD). The aim of this study was to investigate whether QNZ mediates oxidative stress and inflammation contributed to IL-1ß-induced nucleus pulposus (NP) cells degeneration in vitro. PATIENTS AND METHODS: NP were isolated cells from human disc samples collected from patients and the IL-1ß-induced NP cells degenerated model was constructed. The cells were randomly divided into 3 groups, namely, Control group, IL-1ß group (10 µM), QNZ + IL-1ß group (containing 10 nM QNZ and 10 µM IL-1ß). Then, the cell viability was determined by CCK-8 assay, and the levels of collagen I, collagen II, aggrecan, p16, p53, ß-galactosidase (ß-gal), antioxidant enzymes, 8-hydroxy-2-deoxyguanosine (8-OHdG), NF-κB/MAPKs signaling-related proteins and inflammatory factors were examined using Western blot and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in NP cells. Finally, the expressions of IL-1ß, IL-6, and TNF-α in the cell supernatants were also determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: This study showed that IL-1ß promoted the progress of IDD, with markedly increased expressions of collagen I, p16, p53, and ß-gal, as well as decreased expressions of collagen II and aggrecan. However, QNZ treatment could reverse the effects of IL-1ß. It was found that cell proliferation was increased, ROS level was decreased, antioxidant enzymes were upregulated, and inflammatory factors were reduced after QNZ stimulation. Moreover, NF-κB/MAPKs signaling proteins IKKß, IκBα, p65, ERK, JNK, and p38 were significantly dephosphorylated by QNZ. CONCLUSIONS: These results indicated that QNZ prevented NP degradation via restraining oxidative stress and inflammation through inhibition of the NF-κB/MAPKs signaling pathway. QNZ may become a novel insight into the therapy of IVDD in the future.

Increased glycophorin A somatic cell variant frequency in arsenic-exposed patients of Guizhou, China.

Exposure to arsenic through domestic burning arsenic-containing coal causes various tumors in a population of Guizhou, China. The glycophorin A (GPA) assay is a human mutation assay detecting somatic variation in erythrocytes expressing the MN blood type, and was used to assess genotoxicity of arsenic-exposed patients. Peripheral blood was collected from 18 adult healthy subjects and 40 arsenic-exposed patients in heparin-treated tubes. Erythrocytes were isolated, fixed in formalin and immuno-labeled with fluorescent antibodies against GPA, followed by flow cytometry analysis. Arsenic exposure increased the variant frequency (expressed as the number of variant red cells per 10(6) erythrocytes): NN, 3.7 in healthy subjects versus 21.2 in arsenic-exposed patients; N phi, 12.6 versus 33.1; MM, 13.1 versus 110; and M phi, 5.2 versus 20.3. The total GPA variant frequency was increased about five-fold (34.7 in healthy subjects versus 185 in arsenosis patients). Furthermore, the variant frequency was significantly higher in skin tumor-bearing patients: NN, 19.4 in arsenic-exposed non-tumor patients versus 31.5 in tumor-bearing patients; N phi, 29.5 versus 54.5; MM, 102 versus 159; M phi, 15.9 versus 45.1. Total GPA variant frequency in arsenic-exposed patients bearing skin tumors was significantly increased compared to patients without skin tumors (167 versus 290). The relationship between arsenic exposure history and GPA variant frequency was less evident. These data demonstrate that arsenic exposure is associated with mutations at the GPA locus, an effect exaggerated in patients bearing arsenic-induced skin tumors. The variant frequency of GPA could be a useful biomarker for arsenic exposure and arsenic carcinogenesis.