Excitotoxicity induced by NMDA receptor (NMDAR) activation is a major cause of neuronal death in ischemic stroke. However, past efforts of directly targeting NMDARs have unfortunately failed in clinical trials. Here, we reveal an unexpected mechanism underlying NMDAR-mediated neurotoxicity, which leads to the identification of a novel target and development of an effective therapeutic peptide for ischemic stroke.
View Article and Find Full Text PDFActivation of spinal cord microglia contributes to the development of peripheral nerve injury-induced neuropathic pain. However, the molecular mechanisms underlying microglial function in neuropathic pain are not fully understood. We identified that the voltage-gated proton channel Hv1, which is functionally expressed in spinal microglia, was significantly increased after spinal nerve transection (SNT).
View Article and Find Full Text PDFTraumatic injury to the spinal cord initiates a series of pathological cellular processes that exacerbate tissue damage at and beyond the original site of injury. This secondary damage includes oxidative stress and inflammatory cascades that can lead to further neuronal loss and motor deficits. Microglial activation is an essential component of these secondary signaling cascades.
View Article and Find Full Text PDFMicroglia have been shown to be of critical importance to the progression of temporal lobe epilepsy. However, the broad transcriptional changes that these cells undergo following seizure induction is not well understood. As such, we utilized RNAseq analysis upon microglia isolated from the hippocampus to determine expression pattern alterations following kainic acid induced seizure.
View Article and Find Full Text PDFNiche astrocytes have been reported to promote neuronal differentiation through juxtacrine signaling. However, the effects of astrocytes on neuronal differentiation following ischemic stroke are not fully understood. In the present study, transplanted astrocytes and neural stem cells (NSCs) were transplanted into the ischemic striatum of transient middle cerebral artery occlusion (MCAO) model rats 48 h following surgery.
View Article and Find Full Text PDFThe therapeutic benefits of bone marrow-derived mesenchymal stem cell (BM-MSC) transplantation for ischemic stroke have been extensively demonstrated. However, studies on the optimal cell dose for intravenous administration are still limited. This study aimed to determine an appropriate cell dose for BM-MSC intravenous transplantation and to investigate the effect of cell dose on vascular remodeling in a rat model of ischemic stroke.
View Article and Find Full Text PDFBackground: We investigated the effect of a small molecular inhibitor of heat shock protein (HSP), quercetin, on tumor radiofrequency (RF) ablation, and explored the underlying molecular mechanisms.
Methods: In in vivo study, rats with R3230 breast adenocarcinoma were sacrificed 24 h post-treatment and gross coagulation areas were compared, and next, randomized into four treatment arms (control, quercetin alone, RF alone, and combination) for Kaplan-Meier analysis of defined endpoint survival. Then the distribution and expression levels of heat shock protein 70 (HSP70), cleaved caspase-3 and heat shock factor 1 (HSF1) were analyzed after different treatments.
Inflammation drives asthma and atherosclerosis. Clinical studies suggest that asthmatic patients have a high risk of atherosclerosis. Yet this hypothesis remains uncertain, given that Th2 imbalance causes asthma whereas Th1 immunity promotes atherosclerosis.
View Article and Find Full Text PDFThe mechanisms underlying the development of complications in type 1 diabetes (T1D) are poorly understood. Disease modeling of induced pluripotent stem cells (iPSCs) from patients with longstanding T1D (disease duration ≥ 50 years) with severe (Medalist +C) or absent to mild complications (Medalist -C) revealed impaired growth, reprogramming, and differentiation in Medalist +C. Genomics and proteomics analyses suggested differential regulation of DNA damage checkpoint proteins favoring protection from cellular apoptosis in Medalist -C.
View Article and Find Full Text PDFHeat shock protein 27 (HSP27) is an important regulator involved in the development of lung cancer. However, limited evidence exists concerning the underlying molecular mechanisms of its action. The results of the present study revealed that HSP27 was highly expressed in the lung cancer tissues of mice.
View Article and Find Full Text PDFDue to the epidemic obesity and associated diabetes, the incidence of atherosclerosis is increasing worldwide. Atherosclerosis is a chronic inflammatory disease characterized by the hardening and narrowing of arteries with plaques that consist of inflammatory cells, dead endothelial cells, lipids, and often hyper proliferated vascular smooth muscle cells. During the development of atherosclerosis, vascular endothelial cell (EC) apoptosis induced by the adipokine tumor necrosis factor alpha (TNF-α), is an early event in the plaque formation.
View Article and Find Full Text PDFWorld J Gastroenterol
February 2015
Aim: To investigate the treatment strategies and long-term outcomes of radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) in difficult locations and to compare the results with non-difficult HCC.
Methods: From 2004 to 2012, a total of 470 HCC patients underwent ultrasound-guided percutaneous RFA. Among these HCC patients, 382 with tumors located ≤ 5 mm from a major vessel/bile duct (n = 87), from peripheral important structures (n = 232) or from the liver capsule (n = 63) were regarded as difficult cases.
Objective: Atherosclerosis is a chronic inflammatory and immune vascular disease, and clinical and experimental evidence has indicated an important role of complement activation products, including the terminal membrane attack complex (MAC), in atherogenesis. Here, we investigated whether complement inhibition represents a potential therapeutic strategy to treat/prevent atherogenesis using CR2-Crry, a recently described complement inhibitor that specifically targets to sites of C3 activation.
Methods And Results: Previous studies demonstrated that loss of CD59 (a membrane inhibitor of MAC formation) accelerated atherogenesis in Apoe deficient (Apoe(-/-)) mice.
Proc Natl Acad Sci U S A
September 2013
An immature state of cellular differentiation--characterized by stem cell-like tendencies and impaired differentiation--is a hallmark of cancer. Using glioblastoma multiforme (GBM) as a model system, we sought to determine whether molecular determinants that drive cells toward terminal differentiation are also genetically targeted in carcinogenesis and whether neutralizing such genes also plays an active role to reinforce the impaired differentiation state and promote malignancy. To that end, we screened 71 genes with known roles in promoting nervous system development that also sustain copy number loss in GBM through antineoplastic assay and identified A2BP1 (ataxin 2 binding protein 1, Rbfox1), an RNA-binding and splicing regulator that is deleted in 10% of GBM cases.
View Article and Find Full Text PDFIschemic stroke is a leading cause of death worldwide, yet therapies are limited. During periods of ischemia following reperfusion in ischemic stroke, not only loss of energy supply, but a few other factors including mitochondrial dysfunction and oxidative stress also make vital contribution to neuronal injury. Here we synthesized a steroid compound 5α-androst-3β,5,6β-triol by 3 steps starting from dehydroepiandrosterone and examined its effect on mitochondrial function and oxidative stress in primary cultured cortical neurons exposed to hypoxia followed by reoxygenation.
View Article and Find Full Text PDFPhagocytic cell NADPH oxidase (NOX) generates reactive oxygen species (ROS) as part of innate immunity. Unfortunately, ischemia can also induce this pathway and inflict damage on native cells. The voltage-gated proton channel Hv1 enables NOX function by compensating cellular loss of electrons with protons.
View Article and Find Full Text PDFNeuropathic pain is generally defined as a chronic pain state resulting from peripheral and/or central nerve injury. Effective treatment for neuropathic pain is still lacking, due in part to poor understanding of pathological mechanisms at the molecular level. Neuronal mechanisms of neuropathic pain, especially synaptic plasticity, are the major focus of many investigators.
View Article and Find Full Text PDFRituximab efficacy in cancer therapy depends in part on induction of complement-dependent cytotoxicity (CDC). Human CD59 (hCD59) is a key complement regulatory protein that restricts the formation of the membrane attack complex, thereby inhibiting induction of CDC. hCD59 is highly expressed in B-cell non-Hodgkin's lymphoma (NHL), and upregulation of hCD59 is an important determinant of the sensitivity of NHL cells to rituximab treatment.
View Article and Find Full Text PDFBackground: Complement system, an innate immunity, has been well documented to play a critical role in many inflammatory diseases. However, the role of complement in the pathogenesis of abdominal aortic aneurysm, which is considered an immune and inflammatory disease, remains obscure.
Methods And Results: Here, we evaluated the pathogenic roles of complement membrane attack complex and CD59, a key regulator that inhibits the membrane attack complex, in the development of abdominal aortic aneurysm.
CD59 is a membrane protein inhibitor of the membrane attack complex (MAC) of complement. mCd59 knockout mice reportedly exhibit hemolytic anemia and platelet activation. This phenotype is comparable to the human hemolytic anemia known as paroxysmal nocturnal hemoglobinuria (PNH), in which platelet activation and thrombosis play a critical pathogenic role.
View Article and Find Full Text PDFComplement is a central effector system within the immune system and is implicated in a range of inflammatory disorders. CD59 is a key regulator of complement membrane attack complex (MAC) assembly. The atherogenic role of terminal complement has long been suspected but is still unclear.
View Article and Find Full Text PDFCD59 is a membrane protein inhibitor of the membrane attack complex (MAC) of complement. Humans express only one, whereas mice express two CD59 genes. We previously reported the targeted deletion of the mCd59b gene in which absence of mCd59b together with an unintended down regulation of mCd59a caused hemolytic anemia with spontaneous platelet activation.
View Article and Find Full Text PDFConditional targeted cell ablation is a powerful approach for investigating the pathogenesis of human diseases and in vivo cellular functions. Intermedilysin (ILY) is a cytolytic pore-forming toxin secreted by Streptococcus intermedius that lyses human cells exclusively, owing to its receptor specificity for human CD59. We generated two transgenic mouse strains that express human CD59 either on erythrocytes (strain ThCD59(RBC)) or on endothelia (strain ThCD59(END)).
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