Preventive effects of propofol and ketamine on renal injury in unilateral ureteral obstruction

Propofol Attenuates Airway Inflammation in a Mast Cell-Dependent Mouse Model of Allergic Asthma by Inhibiting the Toll-like Receptor 4/Reactive Oxygen Species/Nuclear Factor κB Signaling Pathway

Propofol, an intravenous anesthetic agent widely used in clinical practice, is the preferred anesthetic for asthmatic patients. This study was designed to determine the protective effect and underlying mechanisms of propofol on airway inflammation in a mast cell-dependent mouse model of allergic asthma. Mice were sensitized by ovalbumin (OVA) without alum and challenged with OVA three times. Propofol was given intraperitoneally 0.5 h prior to OVA challenge. The inflammatory cell count and production of cytokines in the bronchoalveolar lavage fluid (BALF) were detected. The changes of lung histology and key molecules of the toll-like receptor 4 (TLR4)/reactive oxygen species (ROS)/NF-κB signaling pathway were also measured. The results showed that propofol significantly decreased the number of eosinophils and the levels of IL-4, IL-5, IL-6, IL-13, and TNF-α in BALF. Furthermore, propofol significantly attenuated airway inflammation, as characterized by fewer infiltrating inflammatory cells and decreased mucus production and goblet cell hyperplasia. Meanwhile, the expression of TLR4, and its downstream signaling adaptor molecules--myeloid differentiation factor 88 (MyD88) and NF-κB, were inhibited by propofol. The hydrogen peroxide and methane dicarboxylic aldehyde levels were decreased by propofol, and the superoxide dismutase activity was increased in propofol treatment group. These findings indicate that propofol may attenuate airway inflammation by inhibiting the TLR4/MyD88/ROS/NF-κB signaling pathway in a mast cell-dependent mouse model of allergic asthma.

Propofol attenuates cytokine-mediated upregulation of expression of inducible nitric oxide synthase and apoptosis during regeneration post-partial hepatectomy

Purpose:

To determine the effects of propofol and ketamine anesthesia on liver regeneration in rats after partial hepatectomy (PHT).

Methods:

Male Wistar albino rats were assigned randomly to four groups of 10. Anesthesia was induced and maintained with propofol in groups 1 and 2, and with ketamine in groups 3 and 4. PHT was undertaken in groups 1 and 3. Rats in groups 2 and 4 (control groups) underwent an identical surgical procedure, but without PHT. At postoperative day-5, rats were killed. Regenerated liver was removed, weighed, and evaluated (by immunohistochemical means) for expression of inducible nitric oxide synthase (iNOS), endothelial NOS (eNOS), apoptosis protease-activating factor (APAF)-1, and proliferating cell nuclear antigen (PCNA). Also, blood samples were collected for measurement of levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6.

Results:

Between groups 2 and 4, there were no differences in tissue levels of iNOS, eNOS, and APAF-1 or plasma levels of TNF-α and IL-6. eNOS expression was similar in group 1 and group 3. Expression of iNOS and APAF-1 was mild-to-moderate in group 1, but significantly higher in group 3. Groups 1 and 3 showed an increase in PCNA expression, but expression in both groups was comparable. Plasma levels of TNF-α and IL-6 increased to a lesser degree in group 1 than in group 3.

Conclusion:

Propofol, as an anesthetic agent, may attenuate cytokine-mediated upregulation of iNOS expression and apoptosis in an animal model of liver regeneration after partial hepatectomy.

Reduction in miRNA-125b-5p levels is associated with obstructive renal injury

Obstructive renal injury is a common disease that leads to progressive glomerulosclerosis, tubulointerstitial fibrosis and loss of renal function. MicroRNAs (miRNAs/miRs) are small non-coding molecules that may be involved in the progression of many renal diseases. The aim of the present study was to investigate the roles of miRNAs, including miR-125b, miR-326 and miR-324p, in obstructive renal injury. Blood samples were collected from 91 patients with ureteral obstruction and 76 controls to examine renal function. In addition, the levels of miR-125b, miR-326 and miR-324p in patients with ureteral obstruction and controls were determined by the reverse transcription-quantitative polymerase chain reaction. Furthermore, the relationship between miRNA levels and renal function was evaluated by the Mann-Whitney U test. Upregulated levels of serum creatinine (SCr) in patients with ureteral obstruction were observed, identifying the injury of renal function. Although the expression levels of miR-324-5p [1.003 (0.391-2.279) vs. 0.934 (0.579-1.539), P=0.300] and miR-326 [0.840 (0.180-2.020) vs. 0.949 (0.507-1.702), P=0.050] presented no significant difference, the levels of miR-125b-5p [0.755 (0.210-2.110) vs. 0.960 (0.390-1.770), P=0.002] in patients with ureteral obstruction were significantly lower than those in controls. These results indicated that there is a stronger correlation of miR-125b-5p with the occurrence of ureteral obstruction, especially for the female (P=0.0171) and elderly (P=0.0142). Furthermore, the levels of miR-125b-5p (r=-0.175, P=0.038) were closely associated with the serum levels of SCr, suggesting a key role of miR-125b-5p in renal dysfunction. Thus, these findings suggested that miR-125b-5p in patients with ureteral obstruction correlated with renal function, and may be a potential biomarker for obstructive renal injury.

Propofol participates in gastric mucosal protection through inhibiting the toll-like receptor-4/nuclear factor kappa-B signaling pathway

AIMS

Propofol has demonstrated protective effects against digestive injury. Toll-like receptor-4 (TLR4) is involved in gastric mucosal injury. However, it has not yet been clarified whether propofol protects gastric mucosa from ethanol-induced injury and whether the mechanism involved is related to TLR4 activation. Therefore, this prospective study was carried out to address the issue.

METHODS

Gastric mucosal injury was induced in mice by intragastric administration of ethanol. Propofol was given intraperitoneally 30 min before ethanol intragastric administration and, 1h later, gastric specimens were studied using hematoxylin--eosin staining, quantitative real-time RT-PCR, immunohistochemical staining and Western blot assays; serum specimens were studied using ELISA kits.

RESULTS

Propofol at 25mg/kg significantly attenuated ethanol-induced gastric mucosal injury. In addition, propofol pretreatment significantly inhibited the upregulated expression of high-mobility group box-1 (HMGB1) protein, TLR4 and its downstream signaling molecules--myeloid differentiation factor 88 (MyD88) and nuclear factor kappa-B (NF-κB)--in gastric mucosa, while suppressing the increased release of tumor neurosis factor-α (TNF-α) and interleukin-1β (IL-1β) in serum. Furthermore, upregulation of the Bax/Bcl-2 ratio in gastric mucosa was clearly depressed by propofol.

CONCLUSION

Propofol can inhibit HMGB1 expression and TLR4/MyD88/NF-κB-mediated inflammatory responses, and hamper apoptosis, which may contribute to its protective action against ethanol-induced gastric mucosal injury.