Regulation of Vascular Endothelial Cell Polarization and Migration by Hsp70/Hsp90-Organizing Protein

Hsp70/Hsp90-organizing protein (HOP) is a member of the co-chaperone family, which directly binds to chaperones to regulate their activities. The participation of HOP in cell motility and endothelial cell functions remains largely unknown. In this study, we demonstrate that HOP is critically involved in endothelial cell migration and angiogenesis. Tube formation and capillary sprouting experiments reveal that depletion of HOP expression significantly inhibits vessel formation from endothelial cells. Wound healing and transwell migration assays show that HOP is important for endothelial cell migration. By examination of centrosome reorientation and membrane ruffle dynamics, we find that HOP plays a crucial role in the establishment of cell polarity in response to migratory stimulus. Furthermore, our data show that HOP interacts with tubulin and colocalizes with microtubules in endothelial cells. These findings indicate HOP as a novel regulator of angiogenesis that functions through promoting vascular endothelial cell polarization and migration

Antinociceptive Effect of Intrathecal Injection of Genetically Engineered Human Bone Marrow Stem Cells Expressing the Human Proenkephalin Gene in a Rat Model of Bone Cancer Pain

Background. This study aimed to investigate the use of human bone marrow mesenchymal stem cells (hBMSCs) genetically engineered with the human proenkephalin (hPPE) gene to treat bone cancer pain (BCP) in a rat model. Methods. Primary cultured hBMSCs were passaged and modified with hPPE, and the cell suspensions (6 × 106) were then intrathecally injected into a rat model of BCP. Paw mechanical withdrawal threshold (PMWT) was measured before and after BCP. The effects of hPPE gene transfer on hBMSC bioactivity were analyzed in vitro and in vivo. Results. No changes were observed in the surface phenotypes and differentiation of hBMSCs after gene transfer. The hPPE-hBMSC group showed improved PMWT values on the ipsilateral side of rats with BCP from day 12 postoperatively, and the analgesic effect was reversed by naloxone. The levels of proinflammatory cytokines such as IL-1β and IL-6 were ameliorated, and leucine-enkephalin (L-EK) secretion was augmented, in the hPPE-engineered hBMSC group. Conclusion. The intrathecal administration of BMSCs modified with the hPPE gene can effectively relieve pain caused by bone cancer in rats and might be a potentially therapeutic tool for cancer-related pain in humans

Histone deacetylase 6 modulates macrophage infiltration during inflammation

Mice with histone deacetylase 6 (HDAC6) deficiency grow and develop normally but exhibit impaired immune response. The molecular mechanisms for this phenotype remain largely elusive. Methods: A mouse acute peritonitis model was used to study the infiltration of neutrophils and monocyte-derived macrophages. In vitro cell motility assays were performed to analyze monocyte/macrophage recruitment. Fluorescence microscopy and flow cytometry were performed to examine the phagocytic ability of macrophages. Immunofluorescence microscopy was used to investigate protein localization, protrusion formation, and microtubule acetylation. Results: HDAC6 deficiency does not affect neutrophil infiltration, but instead attenuates the infiltration of monocyte-derived macrophages into the peritoneal cavity. HDAC6 plays a specific role in monocyte/macrophage recruitment. Loss of HDAC6 suppresses the phagocytic capacity of macrophages challenged with E. coli. Lipopolysaccharide stimulation results in the translocation of HDAC6 and cortactin from the cytosol to the cell periphery, promotes the formation of filopodial protrusions, and enhances microtubule acetylation around the microtubule-organizing center, all of which are abrogated by HDAC6 deficiency. Conclusion: These findings implicate HDAC6 in the innate immune response and suggest that it may serve as a promising target for the treatment of macrophage-associated immune diseases

Methylprednisolone as Adjunct to Endovascular Thrombectomy for Large-Vessel Occlusion Stroke

Importance It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy. Objective To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO. Design, Setting, and Participants This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023.InterventionsEligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy. Main Outcomes and Measures The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours. Results Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo. Conclusions and Relevance Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability.Trial RegistrationChiCTR.org.cn Identifier: ChiCTR210005172

Antinociceptive Effect of Intrathecal Injection of Genetically Engineered Human Bone Marrow Stem Cells Expressing the Human Proenkephalin Gene in a Rat Model of Bone Cancer Pain

Background. This study aimed to investigate the use of human bone marrow mesenchymal stem cells (hBMSCs) genetically engineered with the human proenkephalin (hPPE) gene to treat bone cancer pain (BCP) in a rat model. Methods. Primary cultured hBMSCs were passaged and modified with hPPE, and the cell suspensions (6 × 106) were then intrathecally injected into a rat model of BCP. Paw mechanical withdrawal threshold (PMWT) was measured before and after BCP. The effects of hPPE gene transfer on hBMSC bioactivity were analyzed in vitro and in vivo. Results. No changes were observed in the surface phenotypes and differentiation of hBMSCs after gene transfer. The hPPE-hBMSC group showed improved PMWT values on the ipsilateral side of rats with BCP from day 12 postoperatively, and the analgesic effect was reversed by naloxone. The levels of proinflammatory cytokines such as IL-1β and IL-6 were ameliorated, and leucine-enkephalin (L-EK) secretion was augmented, in the hPPE-engineered hBMSC group. Conclusion. The intrathecal administration of BMSCs modified with the hPPE gene can effectively relieve pain caused by bone cancer in rats and might be a potentially therapeutic tool for cancer-related pain in humans

Robust Frame Synchronization Scheme for Continuous-Variable Quantum Key Distribution with Simple Process

In continuous-variable quantum key distribution (CVQKD) systems, high-quality data synchronization between two legitimate parties, Alice and Bob, is the premise of the generation of shared secret keys. Synchronization with specially designed frames is an efficient way, but it requires special modulating devices to generate these special frames. Moreover, the extra requirement of special modulating devices makes it technically impossible for some passive preparation schemes. We propose a novel approach to realize synchronization in this paper, which is different from those special-frame-based methods. In our proposed scheme, Alice publishes parts of the original signals as the synchronization frames and Bob takes these frames to perform the synchronization algorithm. Besides, a synchronization feature is applied to deal with phase shifts. The simulation results based on practical data demonstrate that the proposed synchronization scheme not only maintains a high success rate but simplifies the data processing flow at the same time, which dramatically reduces the computational complexity

CYLD regulates RhoA activity by modulating LARG ubiquitination.

Rho family guanosine triphosphatases (GTPases), such as RhoA, Cdc42, and Rac1, play a fundamental role in various cellular processes. The activation of Rho proteins is catalyzed by guanine nucleotide-exchange factors (GEFs), which promote the exchange of GDP for GTP. The precise mechanisms regulating the activation of Rho proteins are not fully understood. Herein, we demonstrate that RhoA activity is regulated by cylindromatosis (CYLD), a deubiquitinase harboring multiple functions. In addition, we find that RhoA-mediated cytoskeletal rearrangement, chromosome separation, and cell polarization are altered in CYLD-depleted cells. Mechanistically, CYLD does not interact with RhoA; instead, it interacts with and deubiquitinates leukemia-associated RhoGEF (LARG). Our data further show that CYLD-mediated deubiquitination of LARG enhances its ability to stimulate the GDP/GTP exchange on RhoA. These data thus identify LARG as a new substrate of CYLD and provide novel insights into the regulation of RhoA activation. Our results also suggest that the LARG-RhoA signaling pathway may play a role in diverse CYLD-mediated cellular events

RiPerC Attenuates Cerebral Ischemia Injury through Regulation of miR-98/PIK3IP1/PI3K/AKT Signaling Pathway

Background. Cerebral ischemic stroke is a refractory disease which seriously endangers human health. Remote ischemic perconditioning (RiPerC) by which the sublethal ischemic stimulus is administered during the ischemic event is beneficial after an acute stroke. However, the regulatory mechanism of RiPerC that relieves cerebral ischemic injury is still not completely clear. Methods. In the present study, we investigated the regulatory mechanism of RiPerC in a rat model of ischemia induced by the middle cerebral artery occlusion (MCAO). Forty-eight adult male Sprague-Dawley (SD) rats were injected intracerebroventricularly with miR-98 agomir, miR-98 antagomir, or their negative controls (agomir-NC, antagomir-NC) 2 h before MCAO or MCAO+RiPerC followed by animal behavior tests and infraction volume measurement at 24 h after MCAO. The expression of miR-98, PIK3IP1, and tight junction proteins in rat hippocampus and cerebral cortex tissues was detected by quantitative polymerase chain reaction (qPCR) and Western blot (WB). Enzyme-linked immunosorbent assay (ELISA) was used to assess the IL-1β, IL-6, and TNF-α levels in the rat serum. Results. The results showed that in MCAO group, the expression of PIK3IP1 was upregulated, but decreased after RiPerC treatment. Then, we found that PIK3IP1 was a potential target of miR-98. Treatment with miR-98 agomir decreased the infraction volume, reduced brain edema, and improved neurological functions compared to control rats. But treating with miR-98 antagomir in RiPerC group, the protective effect on cerebral ischemia injury was canceled. Conclusion. Our finding indicated that RiPerC inhibited the MCAO-induced expression of PIK3IP1 through upregulated miR-98, thereby reducing the apoptosis induced by PIK3IP1 through the PI3K/AKT signaling pathway, thus reducing the cerebral ischemia-reperfusion injury