Sample stacking – Capillary electrophoretic determination of nitrate and nitrite contents as nitric oxide metabolites in honey varieties originated from Anatolia

2021 ◽  
Author(s):  
J. Aftab ◽  
Z. Kalaycıoğlu ◽  
S. Kolaylı ◽  
F.B. Erim

Abstract Nitrate and nitrite ions taken from food are the sources of bioavailable nitric oxide (NO) in the nitrogen cycle. Some beneficial effects of honey on health are attributed to the ability of honey to increase NO production. The variation of nitrate and nitrite levels of honey samples collected from different Anatolia regions were clarified using capillary electrophoresis technique. The sensitivities of both anions were improved with the application of the sample stacking method. Separation buffer consisted of 30 mmol L−1 formic acid and 30 mmol L−1 sodium sulfate at a pH of 4.0. The CE technique revealed that 18 honey samples contained nitrate anion ranged between 2.53 and 31.8 mg kg−1. Nitrite amounts were found in lower amounts in the honey samples as between non-detected and 0.533 mg kg−1. The observed differences in nitrate levels between honey varieties may be a way to determine honey's origin.

2013 ◽  
Vol 477-478 ◽  
pp. 1359-1362
Author(s):  
Qiao Yang ◽  
Xiao Ling Zhang ◽  
Hong Liang Huang

In this study, we developed a fluorescence measurements in microplates for high-throughput determination of nitric oxide (NO) metabolites, which is used as a reliable and sensitive marker of NO production, in biological fluids using a pH-independent fluorescence increasing probe, DAMBO-PH. The sensitivity of this method is lower than that of the other detection methods reported in the literature. This method was demonstrated to be useful for the rapid screening of large numbers of biological and clinical samples, and should be an important tool for further clarifying the physiology, pathology and pharmacology roles of NO.


2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Razika Zeghir-Bouteldja ◽  
Manel Amri ◽  
Saliha Aitaissa ◽  
Samia Bouaziz ◽  
Dalila Mezioug ◽  
...  

Hydatidosis is characterized by the long-term coexistence of larvaEchinococcus granulosusand its host without effective rejection. Previous studies demonstrated nitric oxide (NO) production (in vivo and in vitro) during hydatidosis. In this study, we investigated the direct in vitro effects of NO species: nitrite (NO2−), nitrate (NO3−) and peroxynitrite (ONOO−) on protoscolices (PSCs) viability and hydatid cyst layers integrity for 24 hours and 48 hours. Our results showed protoscolicidal activity ofNO2−andONOO−24 hours and 3 hours after treatment with 320 μM and 80 μM respectively. Degenerative effects were observed on germinal and laminated layers. The comparison of the in vitro effects of NO species on the PSCs viability indicated thatONOO−is more cytotoxic thanNO2−. In contrast,NO3−has no effect. These results suggest possible involvement ofNO2−andONOO−in antihydatic action and point the efficacy of these metabolites as scolicidal agents.


2021 ◽  
Vol 22 (19) ◽  
pp. 10287
Author(s):  
Chih-Hsien Wu ◽  
Yi-Lin Chiu ◽  
Chung-Yueh Hsieh ◽  
Guo-Shiang Tsung ◽  
Lian-Shan Wu ◽  
...  

Cilostazol was suggested to be beneficial to retard in-stent atherosclerosis and prevent stent thrombosis. However, the mechanisms responsible for the beneficial effects of cilostazol are not fully understood. In this study, we attempted to verify the mechanism of the antithrombotic effect of cilostazol. Human umbilical vein endothelial cells (HUVECs) were cultured with various concentrations of cilostazol to verify its impact on endothelial cells. KLF2, silent information regulator transcript-1 (SIRT1), endothelial nitric oxide synthase (eNOS), and endothelial thrombomodulin (TM) expression levels were examined. We found cilostazol significantly activated KLF2 expression and KLF2-related endothelial function, including eNOS activation, Nitric oxide (NO) production, and TM secretion. The activation was regulated by SIRT1, which was also stimulated by cilostazol. These findings suggest that cilostazol may be capable of an antithrombotic and vasculoprotective effect in endothelial cells.


Nutrients ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 984 ◽  
Author(s):  
Selom Avotri ◽  
Danita Eatman ◽  
Karen Russell-Randall

Purpose: Resveratrol (RSV), an antioxidant polyphenol, has demonstrated beneficial effects in various ocular diseases including glaucoma. Our study was designed to evaluate the effects of RSV on nitric oxide synthase (NOS) enzymes, nitric oxide (NO) and interleukin-1 alpha (IL-1 α), in human glaucomatous trabecular meshwork (TM) cells. Methods: Western blot was utilized to determine endothelial and inducible NOS (eNOS, iNOS) expression. The concentration-related effects of RSV on IL-1 α and NO levels were assessed using the respective ELISA kits. Results: Densitometry data showed concentration-related increases in eNOS, and reduction in iNOS expression at high RSV concentrations. RSV treatment (0.1, 1, 10 and 100 µM) resulted in increased NO levels (6 ± 0.7, 7 ± 0.8, 7.3 ± 0.7 and 9.5 ± 1 nM/mg protein, respectively). The average value obtained for control was 4.8 ± 0.6 nM/mg protein. Significant increases in IL-1α levels were observed with lower concentrations of RSV. However, at higher RSV concentrations (10–100 μM), IL-1 levels decreased. Conclusions: Resveratrol increased NO in glaucomatous TM cells, possibly by increasing eNOS expression. Thus, RSV-induced NO production supports the beneficial effects of this antioxidant in glaucoma. Furthermore, our results showing a reduction in iNOS, a contributor to oxidative stress expression, further support RSV’s antioxidant capabilities in vision.


1998 ◽  
Vol 4 (1) ◽  
pp. 27-30 ◽  
Author(s):  
G Giovannoni

Nitric oxide is hypothesised to play a role in the immunopathogenesis of multiple sclerosis. Raised cerebrospinal fluid and serum levels of the nitric oxide metabolites nitrate and nitrite have been described in patients with multiple sclerosis. Cerebrospinal fluid and serum nitrate and nitrite were measured in patients with multiple sclerosis, inflammatory and non-inflammatory neurological diseases, and correlated with the albumin quotient, an index of blood-brain-barrier dysfunction. Patients undergoing diagnostic lumbar and vene puncture were prospectively recruited, clinical data were obtained from the hospital records, and the CSF and serum nitrate and nitrite levels were measured by the nitrate reductase and Griess reaction methods. Nitrate and nitrite, were raised in the CSF and serum of patients with multiple sclerosis and other inflammatory neurological diseases compared to patients with non-inflammatory neurological disorders (median nitrate and nitrite: cerebrospinal fluid=10.3 μM vs 15.4 μMvs 6.6 μM, P50.001, and serum=49.0 μM vs 46.4 μM vs 38.8 μM, P=0.02, respectively). CSF nitrate and nitrite levels correlated with the albumin quotient (n=59, r=0.42, P50.001). This study provides further evidence for a role of nitric oxide in the immunopathogenesis of multiple sclerosis and supports a role for nitric oxide as a possible mediator of inflammatory blood-brain-barrier dysfunction.


2017 ◽  
Author(s):  
Chun-Ying Liu ◽  
Wei-Hua Feng ◽  
Ye Tian ◽  
Gui-Peng Yang ◽  
Pei-Feng Li ◽  
...  

Abstract. We developed a new method for the determination of dissolved nitric oxide (NO) in discrete seawater samples based on a combination of a purge-and-trap set-up and fluorometric detection of NO. 2,3-diaminonaphthalene (DAN) reacts with NO in seawater to form the highly fluorescent 2,3-naphthotriazole (NAT). The fluorescence intensity was linear for NO concentrations in the range from 0.14 nmol L−1 to 19 nmol L−1. We determined a detection limit of 0.068 nmol L−1, an average recovery coefficient of 83.8 % (80.2–90.0 %), and a relative standard deviation of ±7.2 %. With our method we determined for the first time the temporal and spatial distributions of NO surface concentrations in coastal waters of the Yellow Sea off Qingdao and in Jiaozhou Bay during a cruise in November 2009. The concentrations of NO varied from below the detection limit to 0.50 nmol L−1 with an average of 0.26 ± 0.14 nmol L−1. NO surface concentrations were generally enhanced significantly during daytime implying that NO formation processes such as NO2− photolysis are much higher during daytime than chemical NO consumption which, in turn, lead to a significant decrease of NO concentrations during nighttime. In general, NO surface concentrations and measured NO production rates were higher compared to previously reported measurements. This might be caused by the high NO2− surface concentrations encountered during the cruise. Moreover, additional measurements of NO production rates implied that the occurrence of particles and a temperature increase can enhance NO production rates. With the method introduced here we have a reliable and comparably easy to use method at hand to measure oceanic NO surface concentrations which can be used to decipher both its temporal and spatial distributions as well as its biogeochemical pathways in the oceans.


1997 ◽  
Vol 43 (1) ◽  
pp. 19-25 ◽  
Author(s):  
O. Raveh ◽  
N. Peleg ◽  
A. Bettleheim ◽  
I. Silberman ◽  
J. Rishpon

Sign in / Sign up

Export Citation Format

Share Document