Tumor necrosis factor (TNF) receptor-associated factor (TRAF) 2 is an intracellular adapter protein, which, upon TNF stimulation, is directly recruited to the intracellular region of TNF receptor 2 (TNFR2) or indirectly, via TRADD, to the intracellular region of TNF receptor 1 (TNFR1). In cultured human umbilical vein endothelial cells, endogenous TRAF2 colocalizes with the membrane-organizing protein caveolin-1 at regions of enrichment subjacent to the plasma membrane as detected by confocal fluorescence microscopy. Both endogenous and transfected TRAF2 protein coimmunoprecipitate with caveolin-1 in the absence of ligand. Upon TNF treatment, the TRAF2-caveolin-1 complex transiently associates with TRADD, and upon overexpression of TNFR2, the TRAF2-caveolin-1 complex stably associates with and causes redistribution of this receptor as detected by confocal fluorescence microscopy. In human embryonic kidney 293 cells, which have minimal endogenous expression of caveolin-1, cotransfection of TRAF2 and caveolin-1 results in spontaneous association of these proteins which can further associate with and redistribute transfected TNFR2 molecules. The association of caveolin-1 with TNFR2 depends upon TRAF2. Cotransfection of caveolin-1 protein increases TRAF2 protein expression levels in HEK 293 cells, which correlates with enhancement of TNF and TRAF2 signaling, measured as transcription of a NF-B promoter-reporter gene, although the caveolin-enhanced response to TNF is attenuated at higher caveolin levels. These findings suggest that intracellular distribution of activated TNF receptors may be regulated by caveolin-1 via its interaction with TRAF2.

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Background Endoplasmic reticulum stress (ERS)-mediated myocardial inflammation and apoptosis plays an important role in myocardial ischemia/reperfusion (I/R) injury. Dexmedetomidine has been used clinically with sedative, analgesic, and anti-inflammatory properties. This study aimed to determine the effects of dexmedetomidine pretreatment on inflammation, apoptosis, and the expression of ERS signaling during myocardial I/R injury. Methods Rats underwent myocardial ischemia for 30 min and reperfusion for 6 h, and H9c2 cardiomyocytes were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) injury (OGD for 12 h and reoxygenation for 3 h). Dexmedetomidine was administered prior to myocardial ischemia in rats or ODG in cardiomyocytes. In addition, the α2-adrenergic receptor antagonist (yohimbine) or the PERK activator (CCT020312) was given prior to dexmedetomidine treatment. Results Dexmedetomidine pretreatment decreased serum levels of cardiac troponin I, reduced myocardial infarct size, alleviated histological structure damage, and improved left ventricular function following myocardial I/R injury in rats. In addition, dexmedetomidine pretreatment increased cell viability and reduced cytotoxicity following OGD/R injury in cardiomyocytes. Mechanistically, the cardioprotection offered by dexmedetomidine was mediated via the inhibition of inflammation and apoptosis through downregulating the expression of the ERS signaling pathway, including glucose-regulated protein 78 (GRP78), protein kinase R-like endoplasmic reticulum kinase (PERK), C/EBP homologous protein (CHOP), inositol-requiring protein 1 (IRE1), and activating transcription factor 6 (ATF6). Conversely, the protective effects of dexmedetomidine were diminished by blocking the α2 adrenergic receptors with yohimbine or promoting PERK phosphorylation with CCT020312. Conclusion Dexmedetomidine pretreatment protects the hearts against I/R injury via inhibiting inflammation and apoptosis through downregulation of the ERS signaling pathway. Future clinical studies are needed to confirm the cardioprotective effects of dexmedetomidine in patients at risk of myocardial I/R injury.

Pin1 belongs to the peptidyl-prolyl cis-trans isomerases (PPIases) superfamily and catalyzes the cis-trans conversion of proline in target substrates to modulate diverse cellular functions including cell cycle progression, cell motility, and apoptosis. Dysregulation of Pin1 has wide-ranging influences on the fate of cells; therefore, it is closely related to the occurrence and development of various diseases. This review summarizes the current knowledge of Pin1 in disease pathogenesis.

Purpose Surgical stress promotes tumor metastasis. Interleukin (IL)-17 plays a pivotal role in cancer progression, and high IL-17 expression predicts poor prognosis of non-small-cell lung cancer (NSCLC). Lidocaine may exert tumor-inhibiting effects. We hypothesize that intravenous lidocaine attenuates surgical stress and reduces serum IL-17 levels during video-assisted thoracic surgery (VATS) for NSCLC. Methods This randomized, double-blind, placebo-controlled trial included 60 early-stage NSCLC patients undergoing VATS, into a lidocaine group (n = 30; intravenous lidocaine bolus 1.0 mg/kg, and 1.0 mg/kg/h until the end of surgery) or a normal saline control group (n = 30). The primary outcome was serum IL-17 level at 24 hours postoperatively. The secondary outcomes included serum IL-17 level at the time of post-anesthesia care unit (PACU) discharge, serum cortisol level at PACU discharge and postoperative 24 hours, pain scores (0–10) from PACU discharge to 48 hours postoperatively, incidences of postoperative nausea and vomiting, dizziness, and arrhythmia during 0–48 hours postoperatively, and 30-day mortality. Long-term outcomes included chemotherapy, cancer recurrence, and mortality. Results The lidocaine group had lower serum IL-17 at 24 hours postoperatively compared with the control group (23.0 ± 5.8 pg/mL vs 27.3 ± 8.2 pg/mL, difference [95% CI] = −4.3 [−8.4 to −0.2] pg/mL; P = 0.038). The lidocaine group also had reduced serum IL-17 (difference [95% CI] = −4.6 [−8.7 to −0.5] pg/mL), serum cortisol (difference [95% CI] = −37 [−73 to −2] ng/mL), and pain scores (difference [95% CI] = −0.7 [−1.3 to −0.1] points) at PACU discharge. During a median follow-up of 10 (IQR, 9–13) months, 2 patients in the lidocaine group and 6 patients in the control group received chemotherapy, one patient in the control group had cancer recurrence, and no death event occurred. Conclusion Intravenous lidocaine was associated with reduced serum IL-17 and cortisol following VATS procedures in early-stage NSCLC patients. Trial Registration ChiCTR2000030629.