Association between paraoxonase-1 gene promoter T (-107) C polymorphism and coronary artery disease

Background: Paraoxonase-1(PON1), a high-density lipoprotein (HDL) associated enzyme, is believed to contribute in the pathogenesis of coronary artery disease (CAD). The aim of this study was to evaluate the association of PON1 promoter C (-107)T polymorphism with the extent of coronary artery stenosis in Iranian patients. Methods: The RFLP analysis for determination of the C(-107)T genotype distribution and measurement of serum PON1 activities (Paraoxonase and Arylesterase) were performed in 99 patients. They were undergone coronary angiography to determine the number of stenotic vessels and classified into three groups: single vessel disease (SVD), two vessels disease (2VD) and three vessels disease (3VD). Results: The C(-107)T polymorphism was significantly associated with serum arylesterase activity but not with paraoxonase activity. The CC and TT genotypes distributed inversely in SVD as compared with 3VD group. Moreover, the CC high activity genotype frequency decreased with increase of stenotic vessels in patients. Conclusion: The reduced arylesterase activity as a function from the weak promoter activity increases the stenosis severity, so that, we assume it is one of the progressive factors of atherosclerotic process in stenotic vessels

Erythrocyte susceptibility to oxidative stress and antioxidant status in patients with type 1 diabetes

In this study, malondialdehyde (MDA) level as an index of erythrocyte susceptibility to oxidative stress and antioxidant defense system (glutathione level (GSH), glutathione peroxidase enzyme activity (GPx) in erythrocytes and ferric reducing ability of plasma (FRAP) as the total plasma antioxidant capacity were measured in 35 patients with type 1 diabetes and 28 age and sex-matched normal subjects. MDA level was significantly elevated in diabetic patients (650.9 ± 144.3 nmol/g versus 476.5 ± 138.5 nmol/g Hb, P < 0.001). The level of MDA was positively correlated with duration of diabetes (r = 0.29, P < 0.05) and HbA1C (r = 0.39, P < 0.05) and negatively with FRAP (r = -0.3, P < 0.05). The level of GSH and FRAP were lower in patients than controls (7.05 ± 1.6 μmol/g versus 8.24 ± 0.9 μmol/g Hb, and 389.05 ± 82.3 μmol/l versus 520.4 ± 124.1 μmol/l, respectively, P < 0.001). GPx activity was not significantly different between the two groups. GSH and FRAP were negatively correlated with HbA1C (r = -0.334, P < 0.01 and r = -0.5, P < 0.01, respectively). In conclusion, there seems to be an increased susceptibility to oxidative stress and decreased antioxidant defense in patients with type 1 diabetes, which may be due to poor glycemic control. © 2007 Elsevier Ireland Ltd. All rights reserved

Association of variable number of tandem repeats in endothelial nitric oxide synthase gene with coronary artery disease

Endo-derived nitric oxide (NO) is synthesized from L-arginine by endothelium nitric oxide synthase (eNOS). Since reduced NO synthesis has been implicated in the development of coronary atherosclerosis; we hypothesized that polymorphisms of NOS gene might be associated with increased susceptibility to this disorder and coronary artery disease (CAD). We studied the 27 base pair tandem repeat polymorphism in intron4 of the endothelial nitric oxide synthase (eNOS) gene in 141 unrelated CAD patients with positive coronary angiograms in Shahid Rajaee Heart Hospital and 159 age matched control subjects without a history of symptomatic CAD. The study protocol was approved by the Iran University of Medical Sciences Ethics Committee. The eNOS gene intron4a/b VNTR polymorphism was analyzed by polymerase chain reaction. The plasma lipids levels and other risk factors were also determined. The genotype frequencies for eNOS4b/b, eNOS4a/b and eNOS4a/a were 68.8, 29.1 and 2.1 in CAD subjects, and 81, 18.4 and 0.6 in control subjects, respectively. The genotype frequencies differed significantly between the two groups (�2= 6.38 P= 0.041). The frequency of the allele was 16.7 in CAD subjects and 9.8 in control subjects and was significantly higher in the patients (�2= 6.18 P= 0.013, odds ratio=1.84). Plasma lipids, except HDL-C were also remarkablely increased in CAD group

Differential gene-expression of metallothionein 1M and 1G in response to zinc in sertoli TM4 cells

Background: Zinc (Zn) as an important trace element is essential for testicular development and spermatogenesis. Molecular mechanism of Zn action in the reproductive system may be related to metal binding low-molecular weight proteins, metallothioneins (MT). Our objective was to determine the effect of Zn on two important isoforms of MT, MT1M and MT1G genes expression on testicular sertoli cells. Methods: Cultured sertoli TM4 cells were exposed to different concentrations of Zn at different time points. Cellular uptake of Zn was tested using flame atomic absorption spectrometry. The cellular viability and gene expression were assessed by MTT and real-time PCR methods, respectively. Results: The treated cells resulted in higher Zn concentration and cellular viability. The expression of MT1M and MT1G genes in the treated cells were greater than those of the untreated cells (P<0.05). In the high dosage treated group (100 and 500 μM), Zn concentration and expression of MT1M and MT1G genes increased three h after treatment; MT1G gene expression increased more at sixth h. At 18th h of treatment, the expression of both genes especially MT1G, increased dramatically while Zn concentration decreased. Conclusion: Since the increase of MT1G mRNA was coincident with cellular Zn level, it seems that MT1G has a more prominent role than MT1M in the homeostasis of Zn. In addition, Zn at dosage of 50 μM (pharmacologic concentration) may protect cells by increasing the expression of MT genes at longer periods

The effect of amino acids on the growth of microsporum canis and Trichophyton schoenleinii

Background: Amino acids have different effects on the growth of some dermatophytes. Some may encourage growth, while others inhibit it. The concentrations of some amino acids also are an important factor for their effect. To investigate the effects of amino acids on the growth of dermatophytes, the dermatophytes Trichophyton schoenleinii and Microsporum canis, obtained from Iran. Methods: In this study, two concentrations (1g/dL and 0.1g/dL) of 23 amino acids were added to the Sabouraud glucose agar media of these dermatophytes. The experiment was carried out three times. After two weeks, the means of the colonies were compared with the control, which had no amino acids added to the Sabouraud glucose media. Results: The results showed that L-cysteine hydrochloride, L-cysteine, L-aspartic acid, L-glutamic acid and DL-tryptophan and L-tyrosine had the most inhibitory effects on the studied dermatophytes, while arginine L-lysine and L-methionine had moderate effects and the rest of amino acids had less inhibitory, or even stimulatory, effects on the growth of the dermatophytes. M. canis and T. schoenleinii has a different sensitivity to amino acids. This data indicates that sulfur-containing amino acids and acetic amino acids have greater inhibitory effect against these two dermatophytes. This may be an indicator that such amino acids used in, for example, sweetener may have an important role in immunity to these dermatophytes. Thus, some amino acids may be used as a possible treatment for dermatophytosis. Conclusion: Among the amino acids L-cysteine hydrocholoride, glutamic acid, aspartic acid, and tryptophan are the most inhibitory effect s against of T. schoenleinii and M. canis. © 2008, Tehran University of Medical Sciences. All rights reserved

The impact of combined paraoxonase1 Q/R 192 and 5A6A matrix metalloproteinase-3 polymorphisms on coronary artery disease

Background: It has been suggested that Q/R 192 polymorphism of paraoxonase1 (PON1) and 5A/6A polymorphism of matrix metalloproteinase-3 (MMP-3) might be associated with the predisposition to coronary artery disease (CAD). Therefore to investigate the significance of these polymorphisms in the pathogenesis of CAD we performed an association study of the polymorphisms with CAD and the number of diseased vessels in patients with CAD. Methods: We studied the human PON1 and MMP3 gene polymorphisms in patients with CAD by polymerase chain reaction/ restriction fragment length polymorphism (PCR/RFLP). These polymorphisms were determined in 129 CAD patients and 115 control subjects who underwent coronary angiography. CAD was defined as the presence of one or more stenoses>50 in at least one major coronary artery and subjects with 0.05). Conclusion: The combined PON1 192 and MMP-3 5A6A polymorphisms are associated with CAD but don't have any effect on the number of diseased vessels

Adenosine pretreatment attenuates angiotensin II-mediated p38 MAPK activation in a protein kinase A dependent manner

Background: Adenosine is known as a protective and anti-inflammatory nucleoside. Angiotensin II is the main hormone of the renin-angiotensin system. It is associated with endothelial permeability, recruitment, and activation of the immune cells through induction of inflammatory mediators. Matrix metalloproteinase-9 (MMP-9) plays an important role in inflammatory processes mediated by macrophages. Objectives: Investigate whether adenosine pretreatment modulates angiotensin II-induced MMP-9 expression and activation of signaling molecules. Methods: Human monocytic U-937 cells were treated with either adenosine or angiotensin II alone or angiotensin II following a pretreatment with adenosine. Supernatants were analyzed for MMP-9 activity by zymography method. MMP-9 gene expression was analyzed using real-time PCR. Activation of inflammatory mediators IκB-α, NF-κB, JNK, p38 MAPK, and STAT3 were analyzed by a multi-target ELISA kit. Association of Protein kinase A (PKA) in adenosine effects was studied by pre-incubation with H89, a selective PKA inhibitor. Results: Treatment of the cells with angiotensin II significantly increased MMP-9 production (p <0.05). Adenosine pretreatment did not attenuate this angiotensin II effect. Angiotensin II treatment induced NF-κB, JNK and p38 activation. Pretreatment with adenosine prior to angiotensin II stimulation showed a 40 inhibitory effect on p38 induction (p <0.05). This effect was reversed by PKA inhibition. Conclusion: The present data confirmed that monocytic MMP-9 was a target gene for angiotensin II. Adenosine pretreatment did not inhibit MMP-9 increase in response to angiotensin II. However, it showed a potential inhibitory effect on angiotensin II inflammatory signaling

Angiotensin II differentially induces matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 production and disturbs MMP/TIMP balance

Angiotensin II, the main component of the renin-angiotensin system, is associated with cardiovascular diseases such as hypertension, vascular remodeling and inflammation. Remodeling process results from dysregulation of Matrix Metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). MMPs are considered as important target genes for angiotensin II. The aim of this study was to determine the effects of angiotensin II on MMP-9 and TIMP-1 production and MMP/TIMP balance in a monocytic cell type. Human monocytic U-937 cells were cultured and treated with 100 nM angiotensin II. Supernatants were analyzed for MMP-9 and TIMP-1 using ELISA and zymography methods. Real-time PCR was utilized to evaluate relative MMP-9 and TIMP-1 genes expression following treatments. Cytotoxicity potentials of treatments were determined by assaying lactate dehydrogenase leakage from the cells. Stimulation of the monocytic cells with angiotensin II significantly increased MMP-9 and TIMP-1 secretion as measured by ELISA (p<0.05). It also augmented gelatinolytic activity of MMP-9 in the conditioned media as much as 49 (p<0.05). Incubation of the cells with angiotensin II for 12 hr increased MMP-9 and TIMP-1 gene expression 2.7 and 1.8 folds, respectively (p<0.05). Angiotensin II treatments did not establish significant cytotoxic effects. In summary, our data provide further evidences that monocytic MMP-9 is a major effector of angiotensin II. It is induced more efficiently than TIMP-1 by angiotensin II that leads to MMP/TIMP imbalance. Our data also reveal the pivotal participation of these cells in pathological cardiovascular remodeling mediated by angiotensin II. Copyright © 2010, Avicenna Journal of Medical Biotechnology. All rights reserved

Angiotensin II induces NF-κB, JNK and p38 MAPK activation in monocytic cells and increases matrix metalloproteinase-9 expression in a PKC- and Rho kinase-dependent manner

Angiotensin II (ANG II), the main effector of the renin-angiotensin system, is implicated in endothelial permeability, recruitment and activation of immune cells, and also vascular remodeling through induction of inflammatory genes. Matrix metalloproteinases (MMPs) are considered to be important inflammatory factors. Elucidation of ANG II signaling pathways and of possible cross-talks between their components is essential for the development of efficient inhibitory medications. The current study investigates the inflammatory signaling pathways activated by ANG II in cultures of human monocytic U-937 cells, and the effects of specific pharmacological inhibitors of signaling intermediates on MMP-9 gene (MMP-9) expression and activity. MMP-9 expression was determined by real-time PCR and supernatants were analyzed for MMP-9 activity by ELISA and zymography methods. A multi-target ELISA kit was employed to evaluate IκB, NF-κB, JNK, p38, and STAT3 activation following treatments. Stimulation with ANG II (100 nM) significantly increased MMP-9 expression and activity, and also activated NF-κB, JNK, and p38 by 3.8-, 2.8- and 2.2-fold, respectively (P < 0.01). ANG II-induced MMP-9 expression was significantly reduced by 75 and 67, respectively, by co-incubation of the cells with a selective inhibitor of protein kinase C (GF109203X, 5 μM) or of Rho kinase (Y-27632, 15 μM), but not with inhibitors of phosphoinositide 3-kinase (wortmannin, 200 nM), tyrosine kinases (genistein, 100 μM) or of reactive oxygen species (α-tocopherol, 100 μM). Thus, protein kinase C and Rho kinase are important components of the inflammatory signaling pathways activated by ANG II to increase MMP-9 expression in monocytic cells. Both signaling molecules may constitute potential targets for effective management of inflammation

Matrix metalloproteinase-9 and paraoxonase 1 Q/R192 gene polymorphisms and the risk of coronary artery stenosis in Iranian subjects

Purpose: To investigate the association of matrix metalloproteinase-9 (MMP-9) and paraoxonase 1 (PON1) 192 polymorphisms with susceptibility to coronary artery stenosis (CAS) and the number of diseased vessels in patients with CAS. Methods: The study population comprised 302 unrelated Iranian individuals, including 145 patients with CAS and 157 control subjects. Genotypes for MMP-9 and PON1 192 polymorphisms were determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Results: In our study, distributions of the TT genotype of MMP-9 and the RR genotype of PON1 192 were significantly higher in patients compared with healthy control subjects (P0.05). Conclusions: The observation indicates that the polymorphisms in the MMP-9 and PON1 192 genes potentially play a role in the manifestation of coronary atherosclerosis but does not have any effect on the number of diseased vessels in Iran. © 2010 Wiley-Liss, Inc