Hepatic Nitrosative Stress Research Articles

Liver nitrosation and inflammation in septic rats were suppressed by propofol via downregulating TLR4/NF-κB-mediated iNOS and IL-6 gene expressions

AimsPropofol can be applied as an anesthetic or sedative agent for septic patients. Our previous studies showed that propofol ameliorated inflammation- and nitrosative stress-induced cellular insults. This study further evaluated effects of propofol on cecal ligation and puncture (CLP)-induced septic insults to rats and its possible mechanisms. Main methodsWistar rats were administered with CLP and effects of propofol on CLP-induced liver dysfunction and rat death were evaluated. Levels of hepatic or systemic nitrogen oxides (NOx) and interleukin (IL)-6 were quantified. Sequentially, inducible nitric oxide synthase (iNOS) and IL-6 gene expressions, toll-like receptor 4 (TLR4) protein levels, and nuclear factor (NF)-κB translocation were determined. Key findingsSubjecting rats to CLP led to body weight loss, liver weight gain, and death. Administration of propofol lessened CLP-induced augmentations of serum and hepatic nitrosative stress and IL-6 levels. Additionally, propofol suppressed CLP-induced enhancements in levels of hepatic iNOS protein. Furthermore, the CLP-induced iNOS and IL-6 mRNA expressions in the liver were inhibited following propofol administration. Sequentially, subjecting rats to CLP enhanced hepatic TLR4 protein levels and NF-κB translocation to nuclei, but propofol inhibited these augmentations. SignificanceConsequently, exposure to propofol protected against CLP-induced liver dysfunction and increased the survival rates of the animals. This study shows that propofol can protect rats against septic insults through suppression of systemic and hepatic nitrosative and inflammatory stress due to inhibition of TLR4/NF-κB-mediated iNOS and IL-6 mRNA and protein expressions.

Hepatic nitrosative stress in experimental diabetes

AimThe effects of the inhibition of nitrosative stress by aminoguanidine in an experimental model of diabetes mellitus (DM) were investigated. MethodsTwenty-one male Wistar rats were divided into three groups: control (CO), diabetic (DM), and diabetic treated with aminoguanidine (DM+AG). Aminoguanidine (aminoguanidine hemisulfate salt, Sigma Chemical Co., St. Louis, MO, USA) was used at a dose of 50mg/kg (i.p.) during the last 30days of the experiment. The expression levels of liver lipoperoxidation (TBARS - nmol/mg protein), inducible oxide nitric synthase (iNOS), nitrotyrosine and the NFκB nuclear transcription factor p65 were examined using western blot analysis. ResultsThe DM group demonstrated an increase in lipoperoxidation and in the expression of iNOS, nitrotyrosine and p65. Aminoguanidine reduced hepatic lipid peroxidation and protein expression levels of iNOS, nitrotyrosine and p65. ConclusionAminoguanidine treatment reduces liver oxidative and nitrosative stress in diabetic animals. In addition, aminoguanidine reduced the expression of p65 in the liver.