Inducible nitric oxide synthase in the epithelial epididymal cells of the rat

1997 ◽  
Vol 9 (8) ◽  
pp. 789 ◽  
Author(s):  
Barbara Wiszniewska ◽  
Rafal Kurzawa ◽  
Andrzej Ciechanowicz ◽  
Boguslaw Machalinski

The expression of mRNA for inducible nitric oxide synthase (iNOS) in rat epithelial cells of epididymis was investigated with reverse transcription followed by polymerase chain reaction. Immunocytochemical reaction for iNOS was performed to confirm the enzyme’ s localization in the epididymal epithelium. Additionally, an indirect spectrophotometric method for nitric oxide (NO) determination was applied for measurement of nitrite production by cultured epididymal epithelial cells. Inducible NOS mRNA was detected in freshly isolated epithelial cells, in cultured cells without stimulation as well as in cultured cells after stimulation by lipopolysaccharide and interferon-gamma. Inducible NOS immunoreactivity was observed in the apical part of epithelial cells of epididymal sections and in the cytoplasm of cells in culture. Release of nitrite was observedin vitro in both the unstimulated and stimulated cells of caput (1·44 ± 0·94 v. 4·37 ± 2·42 µM) and cauda (0·69 ± 1·21 v. 5·21 ± 2·76 µM) epididymis (P < 0·001). To the best of our knowledge, this is the first study to demonstrate iNOS in the epididymal epithelial cells of the rat. Nitric oxide released by epididymal epithelial cells may act on cells and tissues located nearby. The results may help explain epididymal function: sperm storage, passage and maturation. Excessive epididymal NO production may also play a role in the inflammatory infertility of the male. Extra keyword: iNOS

Author(s):  
Agnieszka Kolasa ◽  
Mariola Marchlewicz ◽  
Rafał Kurzawa ◽  
Wojciech Głąbowski ◽  
Grzegorz Trybek ◽  
...  

AbstractIn our previous studies, we showed that a finasteride-induced DHT deficiency may cause changes in the morphology of the seminiferous epithelium without any morphological alteration of the epididymis. In this study, we demonstrated the constitutive immunoexpression of inducible nitric oxide synthase (iNOS) in the testis and epididymis of Wistar rats treated with finasteride for 28 days (the duration of two cycles of the seminiferous epithelium) and 56 days (the duration of one spermatogenesis). We noted that a 56-day finasteride treatment mainly caused a decrease in the level of circulating DHT, as well as a statistically insignificant decrease in the level of T. The hormone deficiency also led to a change in the iNOS immnoexpression in the testis and epididymis of the finasteride-treated rats. In vitro, DHT did not modify NO production by the epithelial cells of the caput epididymis even when stimulated with LPS and IFNγ, but it did give rise to an increase in NO production by the epithelial cells of the cauda epididymis without the stimulation. DHT did not have a statistically significant influence on estradiol production by cultured, LPS- and IFNγ-stimulated epithelial cells from the caput and cauda epididymis. In conclusion, our data clearly indicates that a finasterideinduced DHT deficiency intensifies the constitutive expression of iNOS in most rat testicular and epididymal cells, so it can be expected that the expression of inducible nitric oxide synthase (iNOS) could be regulated by DHT. On the other hand, the profile of the circulating DHT and T levels strongly suggests that the regulation of constitutive iNOS expression is complex and needs more detailed study.


2008 ◽  
Vol 295 (1) ◽  
pp. L96-L103 ◽  
Author(s):  
Viktor Brovkovych ◽  
Xiao-Pei Gao ◽  
Evan Ong ◽  
Svitlana Brovkovych ◽  
Marie-Luise Brennan ◽  
...  

The myeloperoxidase (MPO)-hydrogen peroxide-halide system is an efficient oxygen-dependent antimicrobial component of polymorphonuclear leukocyte (PMN)-mediated host defense. However, MPO deficiency results in few clinical consequences indicating the activation of compensatory mechanisms. Here, we determined possible mechanisms protecting the host using MPO−/−mice challenged with live gram-negative bacterium Escherichia coli. We observed that MPO−/−mice unexpectedly had improved survival compared with wild-type (WT) mice within 5–12 h after intraperitoneal E. coli challenge. Lungs of MPO−/−mice also demonstrated lower bacterial colonization and markedly attenuated increases in microvascular permeability and edema formation after E. coli challenge compared with WT. However, PMN sequestration in lungs of both groups was similar. Basal inducible nitric oxide synthase (iNOS) expression was significantly elevated in lungs and PMNs of MPO−/−mice, and NO production was increased two- to sixfold compared with WT. Nitrotyrosine levels doubled in lungs of WT mice within 1 h after E. coli challenge but did not change in MPO−/−mice. Inhibition of iNOS in MPO−/−mice significantly increased lung edema and reduced their survival after E. coli challenge, but iNOS inhibitor had the opposite effect in WT mice. Thus augmented iNOS expression and NO production in MPO−/−mice compensate for the lack of HOCl-mediated bacterial killing, and the absence of MPO-derived oxidants mitigates E. coli sepsis-induced lung inflammation and injury.


2016 ◽  
Vol 41 (3) ◽  
Author(s):  
Ayşe Nalbantsoy ◽  
Mert Karış ◽  
Leyla Karakaya ◽  
Yurdanur Akgül

AbstractObjective: The aim of this study is to investigate the in vitro cytotoxicity and iNOS (inducible nitric oxide synthase) inhibitory, and antioxidant activity in order to assess the traditional usage of Liquidambar orientalis Mill resin extract.Methods: Different solvent extracts of Liquidambar orientalis Mill resin were prepared. The cytotoxicity of extracts was determined using MTT (3-(4,5-dimethyl-2-thiazolyl)- 2,5-diphenyl-2H-tetrazoliumbromide) assay. HeLa (Human cervix adenocarcinoma), A-549 (Human alveolar adenocarcinoma), MCF-7 (Human breast adenocarcinoma), CaCo-2 (Human colon colorectal adenocarcinoma), mPANC96 (Human pancreas adenocarcinoma), PC-3 (Human prostate adenocarcinoma), U87MG (Human glioblastoma- astrocytoma) and as a normal cell line HEK293 (Human embryonic kidney cells) and Vero (African green monkey kidney epithelial cells) were used for testing cytotoxicity. RAW 264.7 (murine macrophage cell lines) was used to determine the inhibition levels of inducible nitric oxide synthase (iNOS). HL-60 (human acute myeloid leukemia) was used to determine antioxidant activity as DCF production per cent.Results: Hexane, dichloromethane, methanol and water extracts were prepared, and their iNOS inhibitory, cytotoxic and antioxidant activity were investigated. The estimated IC50 values of extracts varied from 6.68 to 48.90 μg/ ml after treatment with different doses of extracts for 48 h. Inhibition of the hexane, dichloromethane, methanol, and water extracts on LPS-induced NO production in RAW 264.7 macrophage were showed that the all extracts inhibited NO production in activated RAW 264.7 cells, except methanol extract. Hexane, dichloromethane and methanol extracts inhibited NO production with ICConclusion: This study is the first report showing the potential of Liquidambar orientalis Mill resin extracts for cytotoxicity, iNOS inhibition and the antioxidant activity as an alternative therapeutic approach for traditional uses. The results demonstrated that Liquidambar orientalis dichloromethane resin extracts showed strongest cytotoxic effect while all extracts except methanolic extracts exhibited moderate iNOS inhibition. All extracts other than hexane have a potent antioxidant effect in the cellular-based assay. In conclusion, further studies should focus on the purification of the active components of this extracts and to investigate the possible mode of action to obtain a better understanding of their potential use as cytotoxic, anti-inflammatory and antioxidant agents.


2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Rafael Simone Saia ◽  
Fabíola Leslie Mestriner ◽  
Giuliana Bertozi ◽  
Fernando Queiróz Cunha ◽  
Evelin Capellari Cárnio

Cholecystokinin (CCK) was first described as a gastrointestinal hormone. However, apart from its gastrointestinal effects, studies have described that CCK also plays immunoregulatory roles. Taking in account the involvement of inducible nitric oxide synthase- (iNOS-) derived NO in the sepsis context, the present study was undertaken to investigate the role of CCK on iNOS expression in LPS-activated peritoneal macrophages. Our results revealed that CCK reduces NO production and attenuates the iNOS mRNA expression and protein formation. Furthermore, CCK inhibited the nuclear factor- (NF-)κB pathway reducing IκBαdegradation and minor p65-dependent translocation to the nucleus. Moreover, CCK restored the intracellular cAMP content activating the protein kinase A (PKA) pathway, which resulted in a negative modulatory role on iNOS expression. In peritoneal macrophages, the CCK-1R expression, but not CCK-2R, was predominant and upregulated by LPS. The pharmacological studies confirmed that CCK-1R subtype is the major receptor responsible for the biological effects of CCK. These data suggest an anti-inflammatory role for the peptide CCK in modulating iNOS-derived NO synthesis, possibly controlling the macrophage activation through NF-κB, cAMP-PKA, and CCK-1R pathways. Based on these findings, CCK could be used as an adjuvant agent to modulate the inflammatory response and prevent systemic complications commonly found during sepsis.


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