Iranian Biomedical Journal
Year:2011 | Volume:15 | Issue:3|Papers Count:8

Nitric oxide (NO) is a simple ubiquitous signaling molecule and plays important roles in almost every biological system. Recent evidences suggest that NO may act as an endocrine molecule. The aim of this review is considering available literature on endocrine roles of NO and/or its metabolites, i.e. nitrite and nitrate. Existing data suggest the idea that NO is a hormone that after production in tissues, it is stabilized and transported as nitrite and/or Snitrosothiols in the blood to target cells.

Background: HOXA11 and leukemia inhibitory factor (LIF) and basic transcriptional element binding protein1 (BTEB1) are expressed in endometrium throughout the menstrual cycle and show a dramatic increase during the mid-luteal phase at the time of implantation. In this case-control study, the expression pattern of these mRNA was evaluated in patients with endometriosis at the time of implantation. We also describe a semi-quantitative RT-PCR protocol optimized in our laboratory.Methods: Eight patients with endometriosis were considered as our case and 8 fertile women as control group. Expression levels of HOXA11, LIF and BTEB1 mRNA were measured in endometrium during the mid-secretory phase using semi-quantitative RT-PCR.Results: We describe the detailed procedure for the analysis ofHOXA11, LIF and BTEB1 mRNA levels. Endometrial HOXA11 and LIF mRNA expression levels (normalized to b-actin expression) were significantly decreased in endometrium of infertile patients with endometriosis compared with healthy fertile controls at the time of implantation (P<0.05). A similar trend was seen in BTEB1 mRNA expression.Conclusion: The results suggest that the alteration in expression pattern of the some genes could account for some aspects of infertility in endometriosis.

Background: X-ray repair cross-complementing group 1 (XRCC1) gene is a DNA repair gene and its nonsynonymous single nucleotide polymorphisms (SNP) may influence DNA repair capacity which has been considered as a modifying risk factor for cancer development.Methods: A case-control study was conducted to investigate impact of three frequently studied polymorphisms (Arg194Trp, Arg280His and Arg399Gln) on developing differentiated thyroid carcinoma (DTC).Results: Increased risks for DTC were shown in homozygous (odds ratio (OR): 3.66, 95% confidence interval (CI): 0.38-35.60) and in dominant trait (OR: 1.22, 95% CI: 1.64-2.32) of Arg194Trp genotype. Also, for Arg280His genotype, an increased risk for DTC was shown in dominant trait (OR: 1.42, 95% confidence interval (CI): 0.76-2.68), while a mildly reduction of risk for DTC (OR: 0.77, 95% (CI): 0.50-1.17) was estimated in dominantGln genotype of Arg399Gln. Considering combinatory effects of Arg194Trpand Arg280His genotypes on DTC, the calculated OR and 95% CI for being heterozygous for one of Arg194Trpor Arg280His genotypes were 1.57 and 0.90-2.74, respectively.Conclusion: Genotyping of codons 194, 280 and 399 inXRCC1 gene may use in risk assessment of DTC.

Background: Dendritic cells (DC) induce tumor or pathogen-specific T cell responses in humans. Several laboratories have developed culture systems, including maturation factors for human DC from peripheral blood monocytes. We comprehensively compared standard maturation stimulus, an autologous monocyte-conditioned medium (MCM), with heparin for their ability to promote uniformly mature DC that elicit T cell responses.Methods: A short (4-day) priming of plastic adherent monocytes with granulocyte-macrophage colony stimulating factor (GM-CSF) and IL-4 with or without heparin was followed by 48-hour incubation in MCM to generate fully mature and stable DC. Phenotypic and functional analyses were carried out using anti-CD14 and anti-CD83 monoclonal antibodies, and mixed lymphocyte reaction, respectively.Results: We found that fully matured DC with a large amount of cytoplasm and copious dendritic projections were visible at the end of culturing period in the presence of MCM, heparin and MCM plus heparin. Thus, DC generated with these maturation factors are non-adherent and have typical satellite morphology. Flow cytometric analysis using anti-CD14 (monocyte marker) and anti-CD83 (mature DC marker) revealed that expression of CD14 decreased in MCM plus heparin-treated DC, and the expression of CD83 was increased when heparin and MCM used as a maturation factor. Functionally, MCM and MCM plus heparin-treated DC showed stronger mixed leukocyte reaction than heparin alone.Conclusion: These results support the use of the MCM with heparin as maturation factor that could result in functionally mature monocyte-derived DC in comparison to either MCM or heparin alone.

Background: Although opioids suppressive effects on immune system function have been reported, this study demonstrates inflammatory reactions, such as production of pro-inflammatory cytokines and suppression of anti-inflammatory cytokines, are the main causes at organ’s allotransplantation rejection in chronic morphine-treated recipients.Methods: 28 rats were categorized in 4 groups through intra-peritoneal administrations: control, sham, morphine treated animals (20 mg/kg injected of morphine daily until biopsy day), morphine and naloxane treated animals (20 mg/kg morphine and 2 mg/kg naloxane daily injected until biopsy day), which their donors were normal rats. The grafts were done at the 14th day of the experiment. Plasma interleukins levels (IL-6 and IL-10) in three sampling times were measured by ELISA. With almost 80% of macroscopic rejection signs in rats of one group, full thickness skin biopsy has been taken and histological parameters like perivascular infiltrates, epidermal changes, and stromal changes were detected. The statistical significance differences between the control and experimental groups were analyzed using the Kruskal-Wallis, followed by ANOVA post hoc test.Results: Accelerated skin allograft rejection by chronic morphine consumption can be resulted of increased IL-6 concentration and decreased IL-10. The enhancing effects of morphine on the graft inflammation were partially antagonized by Naloxane. It can illustrate the complexity of opiates and immune system connections and should be considered during organ transplantation of opiate addicts.Conclusion: Expansion of skin cells in recipient with chronic morphine administration history may be resulted in failure.

Background: Role of nitric oxide (NO) on expression of morphine conditioning using a solely classic task has been proposed previously. In this work, the involvement of NO on the expression of opioid-induced conditioning in the task paired with an injection of naloxone was investigated.Methods: Conditioning was established in adult male Wistar rats (weighing 200-250 g) using an unbiased procedure. Naloxone (0.05-0.4 mg/kg, i.p.), a selective antagonist of mu-opioid receptor, was administered once prior to morphine response testing. NO agents were administered directly into the central amygdala (CeA) prior to naloxone injection pre-testing.Results: Morphine (2.5-10 mg/kg, s.c.) produced a significant dose-dependent place preference in experimental animals. When naloxone (0.05-0.4 mg/kg, i.p.) was injected before testing of morphine (5 mg/kg, s.c.) response, the antagonist induced a significant aversion. This response was reversed due to injection of L-arginine (0.3-3 mg/rat), intra-CeA prior to naloxone administration. However, pre-injection of L-NAME (intra-CeA), an inhibitor of NO production, blocked this effect.Conclusion: The finding may reflect that NO in the nucleus participates in morphine plus naloxone interaction.

Background: This study examined the effect of grape seed proanthocyanidin extract (GSPE) on lipid peroxidation content and activity of tissue antioxidant enzymes, including catalase, superoxide dismutase and glutathione peroxidase in diabetic rats.Methods: Thirty male rats were divided into three groups of 10 rats each: control, diabetic and diabetic groups that received 500 mg/kg GSPE for 6 weeks. Diabetes was induced by a single intraperitoneal injection of streptozotocin (50 mg/kg body weight). Rats with fasting blood glucose levels above 250 mg/dl were used as diabetic animals. The first 24-hour urinary albumin excretion (UAE) was measured two weeks after diabetes induction and then each week until the end of the experimental period in all groups. Lipid peroxidation content and activities of catalase, superoxide dismutase and glutathione peroxidase were measured in kidney homogenate supernatants. Statistical significance of differences was assessed with one-way ANOVA by SPSS followed by Tukey's t-test. P<0.05 was assumed statistically significant.Results: UAE in diabetic nephropathy rats were significantly higher than in control. In addition, an increase in lipid peroxidation content and decrease in catalase, superoxide dismutase and glutathione peroxidase activities in kidney of diabetic nephropathy rats were observed. The GSPE administration did not affect on body weight, but significantly decreased lipid peroxidation and augmented the activities of antioxidant enzymes studied in kidney of diabetic nephropathy rats as well as reduced UAE and decreased kidney weight.Conclusion: The results suggested that GSPE could ameliorate diabetic nephropathy rats through reduction of oxidative stress and increase in renal antioxidant enzyme activity.

Background: Myeloperoxidase (MPO), which is abundantly expressed in neutrophils, catalyzes the formation of a number of reactive oxidant species. However, evidence has emerged that MPO-derived oxidants contribute to tissue damage and initiation and propagation of inflammatory diseases, particularly, cardiovascular diseases. Therefore, studying the regulatory mechanisms of the enzyme activity is of great importance. For clarifying some possible mechanism of the enzyme activity, kinetic investigations of MPO in the presence of Copper (Cu), Cadmium (Cd), andLead (Pb) ions were carried out in vitro.Methods: MPO was partially purified from human white blood cells using ion-exchange and gel-filtration chromatography techniques. Its activity was measured spectrophotometrically by using tetramethyl benzidine (TMB) as substrate.Results: Purified enzyme had a specific activity of 21.7 U/mg protein with a purity index of about 0.71. Cu inhibited MPO activity progressively up to a concentration of 60 mM at which about 80% of inhibition achieved. The inhibition was non-competitive with respect to TMB. An inhibitory constant (Ki) of about 19 mM was calculated from the slope of repot. Cd and Pb did not show any significant inhibitory effect on the enzyme activity.Conclusion: The results of the present study may indicate that there are some places on the enzyme and enzyme-substrate complex for Cu ions. Binding of Cu ions to these places result in conformational changes of the enzyme and thus, enzyme inhibition. This inhibitory effect of Cu on the enzyme activity might be considered as a regulatory mechanism on MPO activity.