Limits...
Acute oral dose of sodium nitrite induces redox imbalance, DNA damage, metabolic and histological changes in rat intestine

View Article: PubMed Central - PubMed

ABSTRACT

Industrialization and unchecked use of nitrate/nitrite salts for various purposes has increased human exposure to high levels of sodium nitrite (NaNO2) which can act as a pro-oxidant and pro-carcinogen. Oral exposure makes the gastrointestinal tract particularly susceptible to nitrite toxicity. In this work, the effect of administration of a single acute oral dose of NaNO2 on rat intestine was studied. Animals were randomly divided into four groups and given single doses of 20, 40, 60 and 75 mg NaNO2/kg body weight. Untreated animals served as the control group. An NaNO2 dose-dependent decline in the activities of brush border membrane enzymes, increase in lipid peroxidation, protein oxidation, hydrogen peroxide levels and decreased thiol content was observed in all treated groups. The activities of various metabolic and antioxidant defense enzymes were also altered. NaNO2 induced a dose-dependent increase in DNA damage and DNA-protein crosslinking. Histopathological studies showed marked morphological damage in intestinal cells. The intestinal damage might be due to nitrite-induced oxidative stress, direct action of nitrite anion or chemical modification by reaction intermediates.

No MeSH data available.


Related in: MedlinePlus

Comet assay.DNA damage in intestinal mucosal cells was studied by the comet assay as described in Materials and Methods. (A) DNA of cells were visualized under a fluorescent microscope and 25 comets scored per slide. Control; 20 mg/kg body weight NaNO2, I; 40 mg/kg body weight NaNO2, II; 60 mg/kg body weight NaNO2, III; 75 mg/kg body weight NaNO2, IV. (B) Comet tail lengths were recorded using the image analysis system, Komet 5.5, Kinetic Imaging, Liverpool, UK. Results are mean ± standard error of six different samples. *Significantly different at p< 0.05 from control.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC5383256&req=5

pone.0175196.g004: Comet assay.DNA damage in intestinal mucosal cells was studied by the comet assay as described in Materials and Methods. (A) DNA of cells were visualized under a fluorescent microscope and 25 comets scored per slide. Control; 20 mg/kg body weight NaNO2, I; 40 mg/kg body weight NaNO2, II; 60 mg/kg body weight NaNO2, III; 75 mg/kg body weight NaNO2, IV. (B) Comet tail lengths were recorded using the image analysis system, Komet 5.5, Kinetic Imaging, Liverpool, UK. Results are mean ± standard error of six different samples. *Significantly different at p< 0.05 from control.

Mentions: In the comet assay, a dose-responsive increase in tail length was observed in NaNO2 treated groups as compared to control group (Fig 4). This is indicative of DNA degradation and strand breaks. Migration length is considered to be directly related to fragment size and proportional to the level of single stranded breaks and alkali-labile sites [52].


Acute oral dose of sodium nitrite induces redox imbalance, DNA damage, metabolic and histological changes in rat intestine
Comet assay.DNA damage in intestinal mucosal cells was studied by the comet assay as described in Materials and Methods. (A) DNA of cells were visualized under a fluorescent microscope and 25 comets scored per slide. Control; 20 mg/kg body weight NaNO2, I; 40 mg/kg body weight NaNO2, II; 60 mg/kg body weight NaNO2, III; 75 mg/kg body weight NaNO2, IV. (B) Comet tail lengths were recorded using the image analysis system, Komet 5.5, Kinetic Imaging, Liverpool, UK. Results are mean ± standard error of six different samples. *Significantly different at p< 0.05 from control.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5383256&req=5

pone.0175196.g004: Comet assay.DNA damage in intestinal mucosal cells was studied by the comet assay as described in Materials and Methods. (A) DNA of cells were visualized under a fluorescent microscope and 25 comets scored per slide. Control; 20 mg/kg body weight NaNO2, I; 40 mg/kg body weight NaNO2, II; 60 mg/kg body weight NaNO2, III; 75 mg/kg body weight NaNO2, IV. (B) Comet tail lengths were recorded using the image analysis system, Komet 5.5, Kinetic Imaging, Liverpool, UK. Results are mean ± standard error of six different samples. *Significantly different at p< 0.05 from control.
Mentions: In the comet assay, a dose-responsive increase in tail length was observed in NaNO2 treated groups as compared to control group (Fig 4). This is indicative of DNA degradation and strand breaks. Migration length is considered to be directly related to fragment size and proportional to the level of single stranded breaks and alkali-labile sites [52].

View Article: PubMed Central - PubMed

ABSTRACT

Industrialization and unchecked use of nitrate/nitrite salts for various purposes has increased human exposure to high levels of sodium nitrite (NaNO2) which can act as a pro-oxidant and pro-carcinogen. Oral exposure makes the gastrointestinal tract particularly susceptible to nitrite toxicity. In this work, the effect of administration of a single acute oral dose of NaNO2 on rat intestine was studied. Animals were randomly divided into four groups and given single doses of 20, 40, 60 and 75 mg NaNO2/kg body weight. Untreated animals served as the control group. An NaNO2 dose-dependent decline in the activities of brush border membrane enzymes, increase in lipid peroxidation, protein oxidation, hydrogen peroxide levels and decreased thiol content was observed in all treated groups. The activities of various metabolic and antioxidant defense enzymes were also altered. NaNO2 induced a dose-dependent increase in DNA damage and DNA-protein crosslinking. Histopathological studies showed marked morphological damage in intestinal cells. The intestinal damage might be due to nitrite-induced oxidative stress, direct action of nitrite anion or chemical modification by reaction intermediates.

No MeSH data available.


Related in: MedlinePlus