Propofol prevents lung injury after intestinal ischemia–reperfusion by inhibiting the interaction between mast cell activation and oxidative stress

Aims

Both mast cells and oxidative stress are involved in acute lung injury (ALI) induced by intestinal ischemia–reperfusion (IIR). The aim of this study was to investigate whether propofol could improve IIR-induced ALI through inhibiting their interaction.

Main methods

Repetitive, brief IIR or IIR + compound 48/80 was performed in adult Sprague–Dawley rats pretreated with saline, apocynin or propofol. And their lungs were excised for histology, ELISA and protein-expression measurements 2 h after reperfusion.

Key findings

Rats pretreated with saline developed critical ALI 2 h after IIR. We found significant elevations in lung injury scores, lung wet/dry ratio and gp91phox, p47phox, intercellular cell adhesion molecule-1 protein expressions and higher level of malondialdehyde, interleukin-6 contents, and myeloperoxidase activities, as well as significant reductions in superoxide dismutase activities, accompanied with increases in mast cell degranulation evidenced by significant increases in mast cell counts, β-hexosaminidase concentrations, and tryptase expression. And the lung injury was aggravated in the presence of compound 48/80. However, pretreated with propofol and apocynin not only ameliorated the IIR-mediated pulmonary changes beyond the biochemical changes but also reversed the changes that were aggravated by compound 48/80.

Significance

Propofol protects against IIR-mediated ALI, most likely by inhibiting the interaction between oxidative stress and mast cell degranulation.     

Nicotinamide–adenine dinucleotides in acute liver injury induced by ethionine, and a comparison with the effects of salicylate

1. The effects of single doses of ethionine or sodium salicylate on the nicotinamide-adenine dinucleotide content of rat liver have been studied. 2. There was no significant change in the sum of NAD+NADH(2) during the early period (0-2hr.) of the liver injury induced by ethionine but there was a decrease in this value of approx. 30% by 4hr. after administration. 3. Ethionine had no significant effect on the NADP+NADPH(2) during the first 2hr. period after administration. The sum then decreased to a value approx. 70% of the control by 3hr. after dosing but showed a partial recovery at the 4hr. period before decreasing again in later stages of the poisoning. 4. Salicylate produced a very rapid decrease in the NADP+NADPH(2) in the liver after intraperitoneal injection. After 1hr. the decrease was approx. 30% of the initial value; the sum slowly returned towards the normal range during the following 4hr. 5. A high parenteral dose of salicylate was found to cause only a small depression in the concentration of ATP in rat liver in contrast with the rapid depletion produced by ethionine. 6. These results are discussed in terms of the liver disturbances produced by ethionine and salicylate.     

MicroRNA-2861 and microRNA-5115 regulates myocardial ischemia–reperfusion injury through the GPR30/mTOR signaling pathway by binding to GPR30

Myocardial ischemia–reperfusion (I/R) injury, a major contributor to morbidity and mortality, represents a combination of intrinsic cellular response to ischemia and the extrinsic acute inflammatory response. In the present study, microarray analysis of GSE67308 and GSE50885 identified differentially expressed GPR30 and upstream regulatory miR-2861 and miR-5115 in myocardial I/R. Furthermore, GPR30 was confirmed as a common target gene of miR-2861 and miR-5115, and miR-2861 and miR-5115 inhibited GPR30 expression. Poor expression of GPR30 was identified in the myocardial I/R injury mouse model. Overexpressed GPR30 led to alleviated the pathological conditions, diminished myocardial infarct size and apoptosis of myocardial tissue in mice. Moreover, miR-2861 and miR-5115 were found to be highly expressed in the myocardial I/R injury mouse model and to subsequently accelerate the disease progression. Notably, PR30 curtailed the development of myocardial I/R injury through activation of the mTOR signaling pathway. The key findings suggested that miR-2861 and miR-5115 blocked the activation of the GPR30/mTOR signaling pathway by targeting GPR30, thereby accelerating myocardial I/R injury in mice.     

Targeting PI3K/p-Akt/eNOS,Nrf2/HO-1, and NF-κB/p53 signaling pathways by angiotensin 1–7 protects against liver injury induced by ischemia–reperfusion in rats

The liver is an important organ, and hepatic ischemia–reperfusion (IR) injury is a frequent pathophysiological process that can cause significant morbidity and mortality. Thus, our study aimed to investigate the effect of targeting PI3K/p-Akt/eNOS (phosphoinositide 3-kinase/phospho-protein kinase B/endothelial nitric oxide synthase), Nrf2/HO-1 (nuclear factor-erythroid 2-related factor-2/heme oxygenase-1), and NF-κB/p53 (nuclear factor-κB/tumor protein 53) signaling pathways by using angiotensin (1–7) [ang-(1–7)] against hepatic injury induced by IR. Thirty-two male rats were included in sham group, ang-(1–7)-treated group, hepatic IR group, and hepatic IR group treated with ang-(1–7). The levels of hepatic ang-(1–7), angiotensin II (Ang II), angiotensin-converting enzyme 2 (ACE2), HO-1, malondialdehyde (MDA), PI3K, and p-Akt were assessed. The expressions of eNOS and B-cell leukemia/lymphoma-2 (BCL-2) in the liver were determined. Histological assessment and immunohistochemical expression of NF-κB, p53, and Nrf2 were carried out. The levels of reduced glutathione (GSH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in serum were estimated. Results showed that administration of ang-(1–7) to hepatic IR rats led to significant amelioration of hepatic damage through a histological evaluation that was associated with significant upregulation of the expressions of PI3K/p-Akt/eNOS and Nrf2/HO-1 with downregulation of NF-κB/p53 signaling pathways. In conclusion, PI3K/p-Akt/eNOS and Nrf2/HO-1 signaling pathways are involved in the protective effects of ang-(1–7) against hepatic damage induced by IR. Therefore, ang-(1–7) can be used to prevent hepatic IR, which occurs in certain conditions such as liver transplantation, hemorrhagic shock, and severe infection.