CRH upregulates supervillin through ERK and AKT pathways to promote bladder cancer cell migration.

Corticotropin-releasing hormone (CRH) has been well documented playing a role in the regulation of cellular processes, immune responses, and inflammatory processes that can influence the occurrence and development of tumors. Supervillin (SVIL) is a membrane-associated and actin-binding protein, which is actively involved in the proliferation, spread, and migration of cancer cells. This work investigated CRH's influence on bladder cancer cells' migration and relevant mechanisms. By using human bladder cancer cells T24 and RT4 in wound healing experiments and transwell assay, we found that the migration ability of the T24 cells was significantly increased after CRH treatment. In vivo experiments showed that CRH significantly promoted the metastases of T24 cells in cell line-derived xenograft (CDX) mouse model. Interestingly, downregulation of SVIL by SVIL-specifc small hairpin RNAs significantly reduced the promoting effect of CRH on bladder cancer cell migration. Furthermore, CRH significantly increased SVIL messenger RNA and protein expression in T24 cells, accompanied with AKT and ERK phosphorylation in T24 cells. Pretreatment with AKT inhibitor (MK2206) blocked the CRH-induced SVIL expression and ERK phosphorylation. Also, inhibition of ERK signaling pathway by U0126 significantly reduced the CRH-induced SVIL expression and AKT phosphorylation. It suggested that cross-talking between AKT and ERK pathways was involved in the effect of CRH on SVIL. Taken together, we demonstrated that CRH induced migration of bladder cancer cells, in which AKT and ERK pathways -SVIL played a key role.

Methylglyoxal induces endothelial cell apoptosis and coronary microvascular dysfunction through regulating AR-cPLA2 signaling.

OBJECTIVE: Since diabetic patients with coronary microvascular dysfunction (CMD) exhibit high cardiac mortality and women have higher prevalence of non-obstructive coronary artery disease than men, we tried to expand the limited understanding about the etiology and the sex difference of diabetic CMD. APPROACH AND RESULTS: Accumulated methylglyoxal (MGO) due to diabetes promotes vascular damage and it was used for mimicking diabetic status. Flow cytometry analysis and isometric tension measurement were performed to evaluate coronary artery endothelial injury. MGO induced apoptosis of coronary endothelial cells, accompanied by downregulation of androgen receptor (AR). Lentivirus-mediated stable expression of AR in coronary endothelial cells increased anti-apoptotic Bcl-2 expression and attenuated MGO-induced cell apoptosis. cPLA2 activation was the downstream of AR downregulation by MGO treatment. Moreover, MGO also activated cPLA2 rapidly to impair endothelium-dependent vasodilation of coronary arteries from mice. Reactive oxygen species (ROS) overproduction was demonstrated to account for MGO-mediated cPLA2 activation and endothelial dysfunction. Importantly, AR blockade increased endothelial ROS production whereas AR activation protected coronary artery endothelial vasodilatory function from the MGO-induced injury. Although galectin-3 upregulation was confirmed by siRNA knockdown in endothelial cells not to participate in MGO-induced endothelial apoptosis, pharmacological inhibitor of galectin-3 further enhanced MGO-triggered ROS generation and coronary artery endothelial impairment. CONCLUSIONS: Our data proposed the AR downregulation-ROS overproduction-cPLA2 activation pathway as one of the mechanisms underlying diabetic CMD and postulated a possible reason for the sex difference of CMD-related angina. Meanwhile, MGO-induced galectin-3 activation played a compensatory role against coronary endothelial dysfunction.

Urocortin2 attenuates diabetic coronary microvascular dysfunction by regulating macrophage extracellular vesicles.

Diabetic patients develop coronary microvascular dysfunction (CMD) and exhibit high mortality of coronary artery disease. Methylglyoxal (MGO) largely accumulates in the circulation due to diabetes. We addressed whether macrophages exposed to MGO exhibited damaging effect on the coronary artery and whether urocortin2 (UCN2) serve as protecting factors against such diabetes-associated complication. Type 2 diabetes was induced by high-fat diet and a single low-dose streptozotocin in mice. Small extracellular vesicles (sEV) derived from MGO-treated macrophages (MGO-sEV) were used to produce diabetes-like CMD. UCN2 was examined for a protective role against CMD. The involvement of arginase1 and IL-33 was tested by pharmacological inhibitor and IL-33-/- mice. MGO-sEV was capable of causing coronary artery endothelial dysfunction similar to that by diabetes. Immunocytochemistry studies of diabetic coronary arteries supported the transfer of arginase1 from macrophages to endothelial cells. Mechanism studies revealed arginase1 contributed to the impaired endothelium-dependent relaxation of coronary arteries in diabetic and MGO-sEV-treated mice. UCN2 significantly improved coronary artery endothelial function, and prevented MGO elevation in diabetic mice or enrichment of arginase1 in MGO-sEV. Diabetes caused a reduction of IL-33, which was also reversed by UCN2. IL-33-/- mice showed impaired endothelium-dependent relaxation of coronary arteries, which can be mitigated by arginase1 inhibition but can't be improved by UCN2 anymore, indicating the importance of restoring IL-33 for the protection against diabetic CMD by UCN2. Our data suggest that MGO-sEV induces CMD via shuttling arginase1 to coronary arteries. UCN2 is able to protect against diabetic CMD via modulating MGO-altered macrophage sEV cargoes.

CRH/CRHR1 modulates cerebrovascular endothelial cell permeability in association with S1PR2 and S1PR3 under oxidative stress.

Corticotrophin-releasing hormone (CRH) has been demonstrated to participate in vascular inflammation and permeability. Our previous studies have shown that blockade of S1PR2 or CRHR1 inhibited H2O2-induced brain endothelial hyperpermeability via inhibiting cPLA2 phosphorylation. However, little is known about the linkage between S1PRs and CRHR1 in oxidative stress-induced cerebrovascular endothelial hyperpermeability. Here we observed the opposite effects of S1PR2 to those of S1PR3 on the monolayer permeability of bEnd3 cells in response to H2O2. Interestingly, activation of CRHR1 was found to reverse the effects resulting from blockade/silencing of both S1PR2 and S1PR3. In bEnd3 monolayer, blockade/knockdown of S1PR2 reduced the endothelial hyperpermeability and suppressed the tight junction protein ZO-1 redistribution caused by H2O2, along with the inhibition of p38, ERK and cPLA2 phosphorylation. On the contrary, suppression/silencing of S1PR3 further promoted H2O2-induced endothelial hyperpermeability and ZO-1 redistribution, accompanied by the increased phosphorylation of p38, ERK and cPLA2. In the presence of CRH, the effects resulting from the suppression of both S1PR2 and S1PR3 were abolished. Our results elucidate a possible linkage between CRHR1 and S1PR2/S1PR3 involving in the regulation of endothelial monolayer permeability under oxidative stress condition.