Oxidative stress and monooxygenase liver function in patients with coronary heart disease and multiple organ dysfunction syndrome:

Application of transcriptome analysis: Oxidative stress, inflammation and microtubule activity disorder caused by ammonia exposure may be the primary factors of intestinal microvilli deficiency in chicken

Ammonia (NH₃), an inhaled harmful gas, is not only an important volatile in fertilizer production and ranching, but also the main basic component of haze. However, the effect and mechanism of NH₃ on the intestines are still unclear. To investigate the intestinal toxicity of NH₃ inhalation, morphological changes, transcriptome profiles and oxidative stress indicators of jejunum in broiler chicken exposed to NH₃ for 42 days were examined. Results of morphological observation showed that NH₃ exposure caused deficiency of jejunal microvilli and neutrophil infiltration. Transcriptomics sequencing identified 677 differential expressed genes (DEGs) including 358 up-regulated genes and 319 down-regulated genes. Enrichment analysis of obtained DEGs by Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) found that biological functions and pathways affected by NH₃ included antioxidant function, inflammation, microtubule and nutrition transport. Relative genes validation and chemical detection confirmed that NH₃-induced oxidative stress by activating CYPs and inhibiting antioxidant enzymes promoted inflammatory response and decreased microtubule activity, thus destroying the balance of nutritional transporters. Our study perfects the injurious mechanism of NH₃ exposure and provides a new insight and method for environmental risk assessment.

Cytochrome P450-endogenous substrates metabolism is reduced in patients with a multiple organ dysfunction after coronary artery bypass grafting

Aim: To evaluate endogenous toxic substrates and liver monooxygenase function in cardiosurgical patients with multiple organ dysfunction syndrome (MODS). Methods: 45 patients with MODS and 34 patients with an uneventful postoperative period were studied. The endogenous substrates were quantified with blood middle molecules (MM). Liver monooxygenase function was evaluated with antipyrine (AP) pharmacokinetics. Results: On the first postoperative day, MODS patients were characterized by high concentration of toxic substrates (MM: +43.8%) and a significant decrease in liver monooxygenase function (AP clearance: −44%), while controls patients had a mild increase in endogenous substrates and a slight depression in monooxygenase function. On the 3rd–4th postoperative day, in the main group, endogenous substrates increased (MM: +53.1%), while in the control group toxic substrates decreased (MM: +6.9%). In both groups, an increase in liver monooxygenase function was noticed. Major differences were observed on the 10th–12th postoperative day. In the main group, toxic substrates remained elevated (MM: +37.5%) and monooxygenase function was depressed (AP clearance: −45.4%), while in the control group endogenous substrates and monooxygenase function were equal to the baseline. The correlation analysis showed a negative relationship between AP pharmacokinetics and endogenous substrates. Conclusion: Slowdown in liver microsomal oxidation is one of the main reasons for the accumulation of endogenous toxic substrates in MODS cardiac patients.