All patients from Goiás, homozygotes for intron 6 mutation, share with the Spanish patients identical-by-descent (IBD) genomic segments comprising the mutation. The entrance date for the Iberian haplotype at the village was calculated to be approximately 200 years old. This result is in agreement with the historical arrival of Iberian individuals at the Goiás state (BR). Patients from Goiás and the three families from Spain share 1.8 cM (family 14), 1.7 cM (family 15), and a more significant segment of 4.7 cM within family 13. On the other hand, the patients carrying the exon 8 mutation do not share any specific genetic segment, indicating an old genetic distance between them or even no common ancestry. Diet is a major source of human exposure to polycyclic aromatic hydrocarbons (PAHs), of which benzo[a]pyrene (BaP) is the most commonly studied and measured. BaP has been considered to exert its genotoxic effects after metabolic activation by cytochrome P450 (CYP) enzymes whose activity can be modulated by cytochrome P450 oxidoreductase (POR), the electron donor to CYP enzymes. Previous studies showed that BaP-DNA adduct formation was greater in the livers of Hepatic Reductase Null (HRN) ****, in which POR is deleted specifically in hepatocytes, than in wild-type (WT) ****. In the present study we used human hepatoma HepG2 cells carrying a knockout (KO) in the POR gene as a human in vitro model that can mimic the HRN mouse model. Treatment to BaP for up to 48 h caused similar cytotoxicity in POR KO and WT HepG2 cells. However, levels of BaP activation (i.e. BaP-7,8-dihydrodiol formation) were higher in POR KO HepG2 cells than in WT HepG2 cells after 48 h. This also resulted in substantially higher BaP-DNA adduct formation in POR KO HepG2 cells indicating that BaP metabolism is delayed in POR KO HepG2 cells thereby prolonging the effective exposure of cells to unmetabolized BaP. As was seen in the HRN mouse model, these results suggest that cytochrome b5, another component of the mixed-function oxidase system, which can also serve as electron donor to CYP enzymes along with NADHcytochrome b5 redutase, contributes to the bioactivation of BaP in POR KO HepG2 cells. Collectively, these findings indicate that CYPs play a more important role in BaP detoxication as opposed to activation. Chronic kidney disease (CKD) is a multifactorial disorder with an important genetic component, and several studies have demonstrated potential associations with allelic variants. In addition, CKD patients are also characterized by high levels of genomic damage. Nevertheless, no studies have established relationships between DNA damage, or genomic instability present in CKD patients, and gene polymorphisms. https://www.selleckchem.com/products/msdc-0160.html To fill in this gap, the potential role of polymorphisms in genes involved in base excision repair (OGG1, rs1052133; MUTYH, rs3219489; XRCC1, rs25487), nucleotide excision repair (ERCC2/XPD, rs1799793, rs171140, rs13181; ERCC4, rs3136166); phase II metabolism (GSTP1, rs749174; GSTO1, rs2164624; GSTO2, rs156697), and antioxidant enzymes (SOD1, rs17880135, rs1041740, rs202446; SOD2, rs4880; CAT, rs1001179; GPX1, rs17080528; GPX3, rs870406 GPX4, rs713041) were inquired. In addition, some genes involved in CKD (AGT, rs5050; GLO1, rs386572987; SHROOM3, rs17319721) were also evaluated. The genomic damage, the genomic instability, and oxidative damage were evaluated by using the micronucleus and the comet assay in 589 donors (415 CKD patients and 174 controls). Our results showed significant associations between genomic damage and genes directly involved in DNA repair pathways (XRCC1, and ERCC2), and with genes encoding for antioxidant enzymes (SOD1 and GPX1). GSTO2, as a gene involved in phase II metabolism, and MUTYH showed also an association with genomic instability. Interestingly, the three genes associated with CKD (AGT, GLO1, and SHROOM3) showed associations with both the high levels of oxidatively damaged DNA and genomic instability. These results support our view that genomic instability can be considered a biomarker of the CKD status. Dental technicians may be chronically exposed to methyl methacrylate (MMA), used in the production of dental prostheses. We have studied whether occupational exposure to MMA affects genotoxicity biomarkers such as 8-OHdG formation, comet assay, and buccal micronucleus frequency. MMA exposure was assessed via ambient air analysis. Although no significant differences between exposed and non-exposed individuals were seen with respect to blood genotoxicity measurements, we found a higher level of buccal-cell anomalies in the exposed group. Cardiac catheterization procedures are performed on about 20,000 children with congenital heart disease (CHD) annually in China. The procedure, which involves exposure to ionizing radiation, causes DNA damage and may lead to increased cancer risk. We have studied chromosomal aberrations (CA) in peripheral lymphocytes of CHD children. CA frequencies were assessed in an interventional group of 70 children who underwent cardiac catheterization and a control group of 51 children receiving open-heart surgery. Total CA and all chromosome-type aberrations were higher in the exposed children than in the control group. With respect to the type of septal defect, the translocation frequency was higher in patients with ventricular rather than atrial defects. Cardiac catheterization procedures increase CA frequencies and may also increase the risk of cancer. Rho/Rho-kinase downstream of G12/13 plays an important role in the regulation of calcium-independent platelet shape change. We have previously shown that proline-rich tyrosine kinase 2 (Pyk2) is activated downstream of G12/13 pathways. In this study, we evaluated the role of Pyk2 in G12/13-induced platelet shape change. We used low concentrations of YFLLRNP, a heptapeptide binding to protease-activated receptor 1 (PAR1), or PAR4-activating peptide AYPGKF in the presence of Gαq inhibitor YM254890 to selectively stimulate G12/13 pathways. We found that G12/13-induced platelet shape change was completely inhibited in the presence of Pyk2 inhibitors AG17 and TAT-Pyk2-CT, suggesting an important role of Pyk2 in platelet shape change. In addition, AYPGKF-induced shape change in Gq -/- platelets was completely inhibited in the presence of AG17 or RhoA/p160ROCK inhibitor Y27632, confirming the role of Pyk2 in RhoA-dependent shape change. Furthermore, AYPGKF-induced platelet aggregation and dense granule secretion were inhibited by blocking Pyk2 or RhoA.
All patients from Goiás, homozygotes for intron 6 mutation, share with the Spanish patients identical-by-descent (IBD) genomic segments comprising the mutation. The entrance date for the Iberian haplotype at the village was calculated to be approximately 200 years old. This result is in agreement with the historical arrival of Iberian individuals at the Goiás state (BR). Patients from Goiás and the three families from Spain share 1.8 cM (family 14), 1.7 cM (family 15), and a more significant segment of 4.7 cM within family 13. On the other hand, the patients carrying the exon 8 mutation do not share any specific genetic segment, indicating an old genetic distance between them or even no common ancestry. Diet is a major source of human exposure to polycyclic aromatic hydrocarbons (PAHs), of which benzo[a]pyrene (BaP) is the most commonly studied and measured. BaP has been considered to exert its genotoxic effects after metabolic activation by cytochrome P450 (CYP) enzymes whose activity can be modulated by cytochrome P450 oxidoreductase (POR), the electron donor to CYP enzymes. Previous studies showed that BaP-DNA adduct formation was greater in the livers of Hepatic Reductase Null (HRN) mice, in which POR is deleted specifically in hepatocytes, than in wild-type (WT) mice. In the present study we used human hepatoma HepG2 cells carrying a knockout (KO) in the POR gene as a human in vitro model that can mimic the HRN mouse model. Treatment to BaP for up to 48 h caused similar cytotoxicity in POR KO and WT HepG2 cells. However, levels of BaP activation (i.e. BaP-7,8-dihydrodiol formation) were higher in POR KO HepG2 cells than in WT HepG2 cells after 48 h. This also resulted in substantially higher BaP-DNA adduct formation in POR KO HepG2 cells indicating that BaP metabolism is delayed in POR KO HepG2 cells thereby prolonging the effective exposure of cells to unmetabolized BaP. As was seen in the HRN mouse model, these results suggest that cytochrome b5, another component of the mixed-function oxidase system, which can also serve as electron donor to CYP enzymes along with NADHcytochrome b5 redutase, contributes to the bioactivation of BaP in POR KO HepG2 cells. Collectively, these findings indicate that CYPs play a more important role in BaP detoxication as opposed to activation. Chronic kidney disease (CKD) is a multifactorial disorder with an important genetic component, and several studies have demonstrated potential associations with allelic variants. In addition, CKD patients are also characterized by high levels of genomic damage. Nevertheless, no studies have established relationships between DNA damage, or genomic instability present in CKD patients, and gene polymorphisms. https://www.selleckchem.com/products/msdc-0160.html To fill in this gap, the potential role of polymorphisms in genes involved in base excision repair (OGG1, rs1052133; MUTYH, rs3219489; XRCC1, rs25487), nucleotide excision repair (ERCC2/XPD, rs1799793, rs171140, rs13181; ERCC4, rs3136166); phase II metabolism (GSTP1, rs749174; GSTO1, rs2164624; GSTO2, rs156697), and antioxidant enzymes (SOD1, rs17880135, rs1041740, rs202446; SOD2, rs4880; CAT, rs1001179; GPX1, rs17080528; GPX3, rs870406 GPX4, rs713041) were inquired. In addition, some genes involved in CKD (AGT, rs5050; GLO1, rs386572987; SHROOM3, rs17319721) were also evaluated. The genomic damage, the genomic instability, and oxidative damage were evaluated by using the micronucleus and the comet assay in 589 donors (415 CKD patients and 174 controls). Our results showed significant associations between genomic damage and genes directly involved in DNA repair pathways (XRCC1, and ERCC2), and with genes encoding for antioxidant enzymes (SOD1 and GPX1). GSTO2, as a gene involved in phase II metabolism, and MUTYH showed also an association with genomic instability. Interestingly, the three genes associated with CKD (AGT, GLO1, and SHROOM3) showed associations with both the high levels of oxidatively damaged DNA and genomic instability. These results support our view that genomic instability can be considered a biomarker of the CKD status. Dental technicians may be chronically exposed to methyl methacrylate (MMA), used in the production of dental prostheses. We have studied whether occupational exposure to MMA affects genotoxicity biomarkers such as 8-OHdG formation, comet assay, and buccal micronucleus frequency. MMA exposure was assessed via ambient air analysis. Although no significant differences between exposed and non-exposed individuals were seen with respect to blood genotoxicity measurements, we found a higher level of buccal-cell anomalies in the exposed group. Cardiac catheterization procedures are performed on about 20,000 children with congenital heart disease (CHD) annually in China. The procedure, which involves exposure to ionizing radiation, causes DNA damage and may lead to increased cancer risk. We have studied chromosomal aberrations (CA) in peripheral lymphocytes of CHD children. CA frequencies were assessed in an interventional group of 70 children who underwent cardiac catheterization and a control group of 51 children receiving open-heart surgery. Total CA and all chromosome-type aberrations were higher in the exposed children than in the control group. With respect to the type of septal defect, the translocation frequency was higher in patients with ventricular rather than atrial defects. Cardiac catheterization procedures increase CA frequencies and may also increase the risk of cancer. Rho/Rho-kinase downstream of G12/13 plays an important role in the regulation of calcium-independent platelet shape change. We have previously shown that proline-rich tyrosine kinase 2 (Pyk2) is activated downstream of G12/13 pathways. In this study, we evaluated the role of Pyk2 in G12/13-induced platelet shape change. We used low concentrations of YFLLRNP, a heptapeptide binding to protease-activated receptor 1 (PAR1), or PAR4-activating peptide AYPGKF in the presence of Gαq inhibitor YM254890 to selectively stimulate G12/13 pathways. We found that G12/13-induced platelet shape change was completely inhibited in the presence of Pyk2 inhibitors AG17 and TAT-Pyk2-CT, suggesting an important role of Pyk2 in platelet shape change. In addition, AYPGKF-induced shape change in Gq -/- platelets was completely inhibited in the presence of AG17 or RhoA/p160ROCK inhibitor Y27632, confirming the role of Pyk2 in RhoA-dependent shape change. Furthermore, AYPGKF-induced platelet aggregation and dense granule secretion were inhibited by blocking Pyk2 or RhoA.
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