ABSTRACT
Atherosclerosis is a leading cause of cardiovascular diseases (CVDs), often resulting in major adverse cardiovascular events (MACEs), such as myocardial infarction and stroke due to the rupture or erosion of vulnerable plaques. Ferroptosis, an iron-dependent form of cell death, has been implicated in the development of atherosclerosis. Despite its involvement in CVDs, the specific role of ferroptosis in atherosclerotic plaque stability remains unclear. In this study, we confirmed the presence of ferroptosis in unstable atherosclerotic plaques and demonstrated that the ferroptosis inhibitor ferrostatin-1 (Fer-1) stabilizes atherosclerotic plaques in apolipoprotein E knockout (Apoe-/-) mice. Using bioinformatic analysis combining RNA sequencing (RNA-seq) with single-cell RNA sequencing (scRNA-seq), we identified Yes-associated protein 1 (YAP1) as a potential key regulator of ferroptosis in vascular smooth muscle cells (VSMCs) of unstable plaques. In vitro, we found that YAP1 protects against oxidized low-density lipoprotein (oxLDL)-induced ferroptosis in VSMCs. Mechanistically, YAP1 exerts its anti-ferroptosis effects by regulating the expression of glutaminase 1 (GLS1) to promote the synthesis of glutamate (Glu) and glutathione (GSH). These findings establish a novel mechanism where the inhibition of ferroptosis promotes the stabilization of atherosclerotic plaques through the YAP1/GLS1 axis, attenuating VSMC ferroptosis. Thus, targeting the YAP1/GLS1 axis to suppress VSMC ferroptosis may represent a novel strategy for preventing and treating unstable atherosclerotic plaques.
Subject(s)
Ferroptosis , Muscle, Smooth, Vascular , Plaque, Atherosclerotic , YAP-Signaling Proteins , Animals , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Mice , Plaque, Atherosclerotic/metabolism , Plaque, Atherosclerotic/pathology , YAP-Signaling Proteins/metabolism , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Humans , Male , Mice, Inbred C57BL , Atherosclerosis/metabolism , Atherosclerosis/pathology , Atherosclerosis/genetics , Mice, Knockout , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Phenylenediamines/pharmacology , Cyclohexylamines/pharmacology , Apolipoproteins E/metabolism , Apolipoproteins E/geneticsABSTRACT
OBJECTIVES: Chronic hyperglycemia is considered as an important factor to promote the neurodegenerative process of brain, and the synaptic plasticity as well as heterogeneity of hippocampal cells are thought to be associated with cognitive dysfunction in the early process of neurodegeneration. To date, fibronectin type III domain-containing protein 5 (FNDC5) has been highlighted its protective role in multiple neurodegenerative diseases. However, the potential molecular and cellular mechanisms of FNDC5 on synaptic plasticity regulation in cognitive impairment (CI) induced by diabetics are still need to known. METHODS/DESIGN: To investigate the heterogeneity and synaptic plasticity of hippocampus in animals with CI state induced by hyperglycemia, and explore the potential role of FNDC5 involved in this process. Firstly, the single cell sequencing was performed based on the hippocampal tissue from db diabetic mice induced CI and normal health control mice by ex vivo experiments; and then the integrated analysis and observations validation using Quantitative Real-time PCR, western blot as well as other in vitro studies. RESULTS: We observed and clarified the sub-cluster of type IC spiral ganglion neurons expressed marker genes as Trmp3 and sub-cluster of astrocytes with marker gene as Atp1a2 in hippocampal cells from diabetic animals induced CI and the effect of those on neuron-glial communication. We also found that FNDC5\BDNF-Trk axis was involved in the synaptic plasticity regulation of hippocampus. In high glucose induced brain injury model in vitro, we investigated that FNDC5 significantly regulates BDNF expression and that over-expression of FNDC5 up-regulated BDNF expression (p < 0.05) and can also significantly increase the expression of synapsin-1 (p < 0.05), which is related to synaptic plasticity, In addition, the unbalanced methylation level between H3K4 and H3K9 in Fndc5 gene promoter correlated with significantly down-regulated expression of FNDC5 (p < 0.05) in the hyperglycemia state. CONCLUSION: The current study revealed that the synaptic plasticity of hippocampal cells in hyperglycemia might be regulated by FNDC5\BDNF-Trk axis, playing the protective role in the process of CI induced by hyperglycemia and providing a target for the early treatment of hyperglycemia induced cognitive dysfunction in clinic.
Subject(s)
Cognitive Dysfunction , Diabetes Mellitus, Experimental , Fibronectins , Hyperglycemia , Animals , Humans , Mice , Brain-Derived Neurotrophic Factor/genetics , Brain-Derived Neurotrophic Factor/metabolism , Cognition , Cognitive Dysfunction/genetics , Cognitive Dysfunction/metabolism , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/metabolism , Fibronectins/genetics , Fibronectins/metabolism , Hippocampus , Hyperglycemia/metabolism , Neuronal Plasticity/physiology , Sodium-Potassium-Exchanging ATPase/metabolismABSTRACT
TM6SF2, predominantly expressed in the liver and intestine, is closely associated with lipid metabolism. We have demonstrated the presence of TM6SF2 in VSMCs within human atherosclerotic plaques. Subsequent functional studies were conducted to investigate its role in lipid uptake and accumulation in human vascular smooth muscle cells (HAVSMCs) using siRNA knockdown and overexpression techniques. Our results showed that TM6SF2 reduced lipid accumulation in oxLDL-stimulated VSMCs, likely through the regulation of lectin-like oxLDL receptor 1 (LOX-1) and scavenger receptor cluster of differentiation 36 (CD36) expression. We concluded that TM6SF2 plays a role in HAVSMC lipid metabolism with opposing effects on cellular lipid droplet content by downregulation of LOX-1 and CD36 expression.
Subject(s)
Muscle, Smooth, Vascular , Scavenger Receptors, Class E , Humans , Muscle, Smooth, Vascular/metabolism , Scavenger Receptors, Class E/genetics , Lipoproteins, LDL/pharmacology , Lipoproteins, LDL/metabolism , Myocytes, Smooth Muscle/metabolism , Down-Regulation , Liver/metabolism , Membrane Proteins/metabolismABSTRACT
BACKGROUND: To study the influencing factors for coronary artery calcification (CAC) in maintenance hemodialysis (MHD) patients and the relationship between CAC and bone metabolism markers and to attempt to find a reliable marker linking vascular calcification and bone metabolism in MHD patients. METHODS: A total of 123 patients were enrolled. CAC was assessed by multislice spiral computed tomography (MSCT), and the CAC score (CACS) was evaluated using the Agaston method. Routine laboratory parameters, including triglycerides (TG), total cholesterol (TC), glucose (Glu), calcium (Ca), phosphorus (P), magnesium (Mg), etc., were measured. Serum markers of bone metabolism, such as alkaline phosphatase(ALP), calcitonin (CT), 25-hydroxy vitamin D [25-(OH)D], intact parathyroid hormone (iPTH), total type I procollagen amino-terminal peptide (tPINP), N-terminal mid-fragment of osteocalcin (N-MID OC), and ß-type I collagen crosslinked carboxyl-terminal peptide (ß-CTX), were also measured. RESULTS: Among 123 MHD patients, 37 patients (30.08%) did not have CAC, and 86 patients (69.92%) had CAC, including 41 patients (47.67%) with mild calcification and 45 patients (52.33%) with moderate to severe calcification. Age, Body Mass Index(BMI), the prevalence of hypertension and diabetes mellitus, TC, Glu, P, and Ca×P in the calcification group were higher than those in the noncalcification group, whereas Mg, iPTH, tPINP, N-MID OC, and ß-CTX were lower than those in the noncalcified group (P < 0.05). Compared with the mild calcification group (0
Subject(s)
Coronary Artery Disease , Vascular Calcification , Humans , Renal Dialysis/adverse effects , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/epidemiology , Parathyroid Hormone , Vascular Calcification/diagnostic imaging , Vascular Calcification/epidemiology , Vascular Calcification/etiology , Peptides , Alkaline PhosphataseABSTRACT
Most cancer deaths are caused by metastasis. The phosphocreatine 3- kinase (PI3K) family includes the I-III classes, with class I divided into 4 subtypes (alpha, ß, γ, delta); and PI3K signaling participates in the regulatory processes of cell proliferation, differentiation, apoptosis, and glucose transport. Moreover, PI3Ks are modulators of cellular membrane lipids involved in signaling and trafficking events. The PI3Kdelta isoform (PI3Kdelta), which is not only specifically expressed in hematopoietic cells, but also in different tumor cell lines, is expressed extensively. The increase in PI3Kdelta activity is often associated with a variety of cancers. Currently, the strategy of tumor therapy based on PI3Kd and its related signaling pathway is developing. Besides its established role in controlling functions in autoimmunity and inflammation, the role of PI3Kdelta in tumor and metastasis is not clearly elucidated, with the effects of inhibiting PI3Kdelta in several types of tumors also remaining unexplored. In addition, the specific inhibitor of PI3Kdelta in tumor progression and metastasis and its underlying mechanism need to be further studied. The purpose of this review is to rationalize the existing functions and mechanisms of PI3Kdelta in tumor metastasis and the relationship with hematopoietic cells in cancers as well cross-talking with miRNA, which provides a new theoretical basis and potential therapeutic target for the drug therapy of tumor metastasis.
Subject(s)
Class I Phosphatidylinositol 3-Kinases/metabolism , Neoplasms/drug therapy , Phosphoinositide-3 Kinase Inhibitors/therapeutic use , Signal Transduction/drug effects , Animals , Carcinogenesis/drug effects , Carcinogenesis/genetics , Carcinogenesis/pathology , Class I Phosphatidylinositol 3-Kinases/antagonists & inhibitors , Class I Phosphatidylinositol 3-Kinases/genetics , Disease Models, Animal , Humans , Mice , Mutation , Neoplasms/genetics , Neoplasms/pathology , Phosphoinositide-3 Kinase Inhibitors/pharmacology , Precision Medicine/methods , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/geneticsABSTRACT
OBJECTIVE: Previous studies showed alterations of brain function in the ventromedial prefrontal cortex of schizophrenia patients. Also, neurochemical changes, especially GABA level alteration, have been found in the medial prefrontal cortex of schizophrenia patients. However, the relationship between GABA level in the ventromedial prefrontal cortex and brain functional activity in schizophrenia patients remains unexplored. METHODS: In total, 23 drug-naïve, first-episode psychosis patients and 26 matched healthy controls completed the study. The single voxel proton magnetic resonance spectroscopy data were acquired in ventromedial prefrontal cortex region, which was used as the seed region for resting-state functional connectivity analysis. The proton magnetic resonance spectroscopy data were processed to quantify the concentrations of GABA+, glutamine and glutamate, and N-acetylaspartate in ventromedial prefrontal cortex. Spearman correlation analysis was used to examine the relationship between metabolite concentration, functional connectivity and clinical variables. Pearson correlation analysis was used to examine the relationship between GABA+ concentration and functional connectivity value. RESULTS: In first-episode psychosis patients, GABA+ level in ventromedial prefrontal cortex was higher and was positively correlated with ventromedial prefrontal cortex-left middle orbital frontal cortex functional connectivity. N-acetylaspartate level was positively correlated with positive symptoms, and the functional connectivity between ventromedial prefrontal cortex and left precuneus was negatively associated with negative symptoms of first-episode psychosis patients. CONCLUSION: Our results indicated that ventromedial prefrontal cortex functional connectivity changes were positively correlated with higher local GABA+ level in first-episode psychosis patients. The altered neurochemical concentration and functional connectivity provide insights into the pathology of schizophrenia.
Subject(s)
Prefrontal Cortex , Psychotic Disorders , Brain/diagnostic imaging , Humans , Magnetic Resonance Imaging , Prefrontal Cortex/diagnostic imaging , Proton Magnetic Resonance Spectroscopy , Psychotic Disorders/diagnostic imagingABSTRACT
Autophagy is a highly conserved catabolic process that mediates degradation of pernicious or dysfunctional cellular components, such as invasive pathogens, senescent proteins, and organelles. It can promote or suppress tumor development, so it is a "double-edged sword" in tumors that depends on the cell and tissue types and the stages of tumor. The epithelial-mesenchymal transition (EMT) is a complex biological trans-differentiation process that allows epithelial cells to transiently obtain mesenchymal features, including motility and metastatic potential. EMT is considered as an important contributor to the invasion and metastasis of cancers. Thus, clarifying the crosstalk between autophagy and EMT will provide novel targets for cancer therapy. It was reported that EMT-related signal pathways have an impact on autophagy; conversely, autophagy activation can suppress or strengthen EMT by regulating various signaling pathways. On one hand, autophagy activation provides energy and basic nutrients for EMT during metastatic spreading, which assists cells to survive in stressful environmental and intracellular conditions. On the other hand, autophagy, acting as a cancer-suppressive function, is inclined to hinder metastasis by selectively down-regulating critical transcription factors of EMT in the early phases. Therefore, the inhibition of EMT by autophagy inhibitors or activators might be a novel strategy that provides thought and enlightenment for the treatment of cancer. In this article, we discuss in detail the role of autophagy and EMT in the development of cancers, the regulatory mechanisms between autophagy and EMT, the effects of autophagy inhibition or activation on EMT, and the potential applications in anticancer therapy.
Subject(s)
Antineoplastic Agents/pharmacology , Autophagy , Neoplasms/metabolism , Antineoplastic Agents/therapeutic use , Autophagy/drug effects , Epithelial-Mesenchymal Transition/drug effects , Gene Regulatory Networks/drug effects , Humans , Molecular Targeted Therapy , Neoplasm Metastasis , Neoplasms/drug therapy , Signal Transduction/drug effectsABSTRACT
The present study aim to investigate the effects of dietary Gelsemium elegans alkaloids supplementation in Megalobrama amblycephala. A basal diet supplemented with 0, 5, 10, 20 and 40â¯mg/kg G. elegans alkaloids were fed to M. amblycephala for 12 weeks. The study indicated that dietary 20â¯mg/kg and 40â¯mg/kg G. elegans alkaloids supplementation could significantly improve final body weight (FBW), weight gain rate (WGR), specific growth rate (SGR), feed conversion ratio (FCR) and protein efficiency ratio (PER) (Pâ¯<â¯0.05). The 20â¯mg/kg and 40â¯mg/kg G. elegans alkaloids groups showed significantly higher whole body and muscle crude protein and crude lipid contents compared to the control group (Pâ¯<â¯0.05). The amino acid contents in muscle were also significantly increased in 20â¯mg/kg and 40â¯mg/kg groups (Pâ¯<â¯0.05). Dietary 40â¯mg/kg G. elegans alkaloids had a significant effect on the contents of LDH, AST, ALT, ALP, TG, TC, LDL-C, HDL-C, ALB and TP in M. amblycephala (Pâ¯<â¯0.05). Fish fed 20â¯mg/kg and 40â¯mg/kg dietary G. elegans alkaloids showed significant increase in complement 3, complement 4 and immunoglobulin M contents. The liver antioxidant enzymes (SOD, CAT and T-AOC) and MDA content significantly increased at 20â¯mg/kg and 40â¯mg/kg G. elegans alkaloids supplement (Pâ¯<â¯0.05). The mRNA levels of immune-related genes IL-1ß, IL8, TNF-α and IFN-α were significantly up-regulated, whereas TGF-ß and IL10 genes were significantly down-regulated in the liver, spleen and head kidney of fish fed dietary supplementation with 20â¯mg/kg and 40â¯mg/kg G. elegans alkaloids. After challenge with Aeromonas hydrophila, significant higher survival rate was observed at 20â¯mg/kg and 40â¯mg/kg G. elegans alkaloids supplement (Pâ¯<â¯0.05). Therefore, these results indicated that M. amblycephala fed a diet supplemented with 20â¯mg/kg and 40â¯mg/kg G. elegans alkaloids could significantly promote its growth performance, lipids and amino acids deposition, immune ability and resistance to Aeromonas hydrophila.
Subject(s)
Cyprinidae/immunology , Disease Resistance/immunology , Fish Diseases/prevention & control , Gelsemium/chemistry , Plant Extracts/pharmacology , Adjuvants, Immunologic/pharmacology , Aeromonas hydrophila/physiology , Alkaloids/chemistry , Alkaloids/pharmacology , Animal Feed/analysis , Animals , Cyprinidae/growth & development , Diet/veterinary , Dietary Supplements/analysis , Dose-Response Relationship, Drug , Fish Diseases/immunology , Fish Proteins/genetics , Fish Proteins/metabolism , Gram-Negative Bacterial Infections/immunology , Gram-Negative Bacterial Infections/prevention & control , Gram-Negative Bacterial Infections/veterinary , Plant Extracts/chemistryABSTRACT
Numerous plant extracts used as feed additives in aquaculture have been shown to stimulate appetite, promote growth and enhance immunostimulatory and disease resistance in cultured fish. However, there are few studies on the famous Chinese herbal medicine Gelsemium elegans, which attracts our attention. In this study, we used the Megalobrama amblycephala to investigate the effects of G. elegans alkaloids on fish intestinal health after diet supplementation with 0, 5, 10, 20 and 40â¯mg/kg G. elegans alkaloids for 12 weeks. We found that dietary G. elegans alkaloids at 40â¯mg/kg improved intestinal morphology by increasing villus length, muscle thickness and villus number in the foregut and midgut and muscle thickness in the hindgut (Pâ¯<â¯0.05). These alkaloids also significantly improved intestinal antioxidant capabilities by increasing superoxide dismutase, catalase, total antioxidant capacity and malondialdehyde levels and up-regulated intestinal Cu/Zn-SOD and Mn-SOD (Pâ¯<â¯0.05) at 20 and 40â¯mg/kg. Dietary G. elegans alkaloids improved intestinal immunity via up-regulating the pro-inflammatory cytokines IL-1ß, IL-8, TNF-α and IFN-α and down-regulating expression of the anti-inflammatory cytokines IL-10 and TGF-ß (Pâ¯<â¯0.05) at 20 and 40â¯mg/kg. The expression of Toll-like receptors TRL1, 3, 4 and 7 were also up-regulated in intestine of M. amblycephala (Pâ¯<â¯0.05). In intestinal microbiota, the abundance of Proteobacteria was increased while the Firmicutes abundance was decreased at phylum level after feeding the alkaloids (Pâ¯<â¯0.05). The alkaloids also increased the abundance of the probiotic Rhodobacter and decreased the abundance of the pathogenic Staphylococcus at genus level (Pâ¯<â¯0.05). In conclusion, dietary G. elegans alkaloid supplementation promoted intestine health by improving intestine morphology, immunity, antioxidant abilities and intestinal microbiota in M. amblycephala.
Subject(s)
Antioxidants/metabolism , Cyprinidae/physiology , Gastrointestinal Microbiome/drug effects , Gelsemium/chemistry , Immunity, Innate/drug effects , Plant Extracts/metabolism , Animal Feed/analysis , Animals , Cyprinidae/microbiology , Diet/veterinary , Dietary Supplements/analysis , Dose-Response Relationship, Drug , Intestines/anatomy & histology , Intestines/drug effects , Plant Extracts/administration & dosage , Random AllocationABSTRACT
OBJECTIVE: Schizophrenia is associated with impairment in prospective memory, the ability to remember to carry out an intended action in the future. It has been established that cue identification (detection of the cue event signaling that an intended action should be performed) and intention retrieval (retrieval of an intention from long-term memory following the recognition of a prospective cue) are two important processes underlying prospective memory. The purpose of this study was to examine prospective memory deficit and underlying cognitive processes in patients with first-episode schizophrenia. METHODS: This study examined cue identification and intention retrieval components of event-based prospective memory using a dual-task paradigm in 30 patients with first-episode schizophrenia and 30 healthy controls. All participants were also administered a set of tests assessing working memory and retrospective memory. RESULTS: Both cue identification and intention retrieval were impaired in patients with first-episode schizophrenia compared with healthy controls ( ps < 0.05), with a large effect size for cue identification (Cohen's d = 0.98) and a medium effect size for intention retrieval (Cohen's d = 0.62). After controlling for working memory and retrospective memory, the difference in cue identification between patients and healthy controls remained significant. However, the difference in intention retrieval between the two groups was no longer significant. In addition, there was a significant inverse relationship between cue identification and negative symptoms ( r = -0.446, p = 0.013) in the patient group. CONCLUSION: These findings suggest that both cue identification and intention retrieval in event-based prospective memory are impaired in patients with first-episode schizophrenia. Cue identification and intention retrieval could be potentially used as biomarkers for early detection and treatment prognosis of schizophrenia. In addition, addressing cue identification deficit through cognitive enhancement training may potentially improve negative symptoms as well.
Subject(s)
Cues , Intention , Memory Disorders/physiopathology , Memory, Episodic , Mental Recall/physiology , Schizophrenia/physiopathology , Adult , Female , Humans , Male , Memory Disorders/etiology , Schizophrenia/complications , Young AdultABSTRACT
OBJECTIVE: To investigate effects of miR-503 on cisplatin sensitivity in BEL-7402 cells by targeting of bcl-2.â© Methods: MiR-503 and bcl-2 mRNA expression levels in hepatocellular carcinoma cells were measured by real-time quantitative (qRT)-PCR; Bcl-protein level was detected by Western blot; miR-503 mimics were transiently transfected to the BEL-7402 cells by liposome transfection; potential target genes of miR-503 were predicted by Bioinformatics software; miR-503 potential targets were validated by dual luciferase activity; and the cell viability was measured by MTT assay. â© Results: MiR-503 level was down-regulated and Bcl-2 protein expression level was up-regulated in BEL-7402 cells compared with HL-7702 cells. MiR-503 could interact with bcl-2 and inhibit its expression. Cell vitality with miR-503 transfection was significantly reduced compared to that in the negative control.â© Conclusion: MiR-503 may enhance the sensitivity of BEL-7402 cells to cisplatin and inhibit the cell proliferation by targeting bcl-2.
Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/metabolism , Cisplatin/pharmacology , Liver Neoplasms/metabolism , MicroRNAs/metabolism , Neoplasm Proteins/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/genetics , Cell Line, Tumor , Cell Proliferation , Cell Survival , Down-Regulation , Humans , Liver Neoplasms/drug therapy , Liver Neoplasms/genetics , MicroRNAs/genetics , Neoplasm Proteins/genetics , Proto-Oncogene Proteins c-bcl-2/genetics , TransfectionABSTRACT
Diabetic peripheral neuropathy (DPN) is the most common complication in both type 1 and type 2 diabetes. Here we studied some phenotypic features of a well-established animal model of type 2 diabetes, the leptin receptor-deficient db(-)/db(-) mouse, and also the effect of long-term (6 mo) treatment with coenzyme Q10 (CoQ10), an endogenous antioxidant. Diabetic mice at 8 mo of age exhibited loss of sensation, hypoalgesia (an increase in mechanical threshold), and decreases in mechanical hyperalgesia, cold allodynia, and sciatic nerve conduction velocity. All these changes were virtually completely absent after the 6-mo, daily CoQ10 treatment in db(-)/db(-) mice when started at 7 wk of age. There was a 33% neuronal loss in the lumbar 5 dorsal root ganglia (DRGs) of the db(-)/db(-) mouse versus controls at 8 mo of age, which was significantly attenuated by CoQ10. There was no difference in neuron number in 5/6-wk-old mice between diabetic and control mice. We observed a strong down-regulation of phospholipase C (PLC) ß3 in the DRGs of diabetic mice at 8 mo of age, a key molecule in pain signaling, and this effect was also blocked by the 6-mo CoQ10 treatment. Many of the phenotypic, neurochemical regulations encountered in lumbar DRGs in standard models of peripheral nerve injury were not observed in diabetic mice at 8 mo of age. These results suggest that reactive oxygen species and reduced PLCß3 expression may contribute to the sensory deficits in the late-stage diabetic db(-)/db(-) mouse, and that early long-term administration of the antioxidant CoQ10 may represent a promising therapeutic strategy for type 2 diabetes neuropathy.
Subject(s)
Diabetes Mellitus, Type 2/complications , Neurons/drug effects , Peripheral Nervous System Diseases/prevention & control , Receptors, Leptin/deficiency , Ubiquinone/analogs & derivatives , Age Factors , Animals , Blotting, Western , Diabetes Mellitus, Type 2/pathology , Electric Stimulation , Ganglia, Spinal/drug effects , Ganglia, Spinal/metabolism , Hyperalgesia/pathology , Immunohistochemistry , In Situ Hybridization , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Neural Conduction/drug effects , Peripheral Nervous System Diseases/etiology , Phospholipase C beta/metabolism , Receptors, Leptin/genetics , Sciatic Nerve/injuries , Sciatic Nerve/pathology , Statistics, Nonparametric , Ubiquinone/pharmacologyABSTRACT
RATIONALE: The sodium-calcium exchanger 1 (NCX1) is predominantly expressed in the heart and is implicated in controlling automaticity in isolated sinoatrial node (SAN) pacemaker cells, but the potential role of NCX1 in determining heart rate in vivo is unknown. OBJECTIVE: To determine the role of Ncx1 in heart rate. METHODS AND RESULTS: We used global myocardial and SAN-targeted conditional Ncx1 knockout (Ncx1(-/-)) mice to measure the effect of the NCX current on pacemaking activity in vivo, ex vivo, and in isolated SAN cells. We induced conditional Ncx1(-/-) using a Cre/loxP system. Unexpectedly, in vivo and ex vivo hearts and isolated SAN cells showed that basal rates in Ncx1(-/-) (retaining ≈20% of control level NCX current) and control mice were similar, suggesting that physiological NCX1 expression is not required for determining resting heart rate. However, increases in heart rate and SAN cell automaticity in response to isoproterenol or the dihydropyridine Ca(2+) channel agonist BayK8644 were significantly blunted or eliminated in Ncx1(-/-) mice, indicating that NCX1 is important for fight or flight heart rate responses. In contrast, the pacemaker current and L-type Ca(2+) currents were equivalent in control and Ncx1(-/-) SAN cells under resting and isoproterenol-stimulated conditions. Ivabradine, a pacemaker current antagonist with clinical efficacy, reduced basal SAN cell automaticity similarly in control and Ncx1(-/-) mice. However, ivabradine decreased automaticity in SAN cells isolated from Ncx1(-/-) mice more effectively than in control SAN cells after isoproterenol, suggesting that the importance of NCX current in fight or flight rate increases is enhanced after pacemaker current inhibition. CONCLUSIONS: Physiological Ncx1 expression is required for increasing sinus rates in vivo, ex vivo, and in isolated SAN cells, but not for maintaining resting heart rate.
Subject(s)
Heart Rate/physiology , Rest/physiology , Sinoatrial Node/physiology , Sodium-Calcium Exchanger/antagonists & inhibitors , Sodium-Calcium Exchanger/genetics , Adrenergic beta-Agonists/pharmacology , Animals , Heart Rate/drug effects , Mice , Mice, Knockout , Mice, Transgenic , Organ Culture Techniques , Sinoatrial Node/cytology , Sinoatrial Node/drug effects , Sodium-Calcium Exchanger/metabolism , Sodium-Calcium Exchanger/physiologyABSTRACT
BACKGROUND: Somatostatin (SST) and some of its receptor subtypes have been implicated in pain signaling at the spinal level. In this study we have investigated the role of SST and its sst2A receptor (sst2A) in dorsal root ganglia (DRGs) and spinal cord. RESULTS: SST and sst2A protein and sst2 transcript were found in both mouse and human DRGs, sst2A-immunoreactive (IR) cell bodies and processes in lamina II in mouse and human spinal dorsal horn, and sst2A-IR nerve terminals in mouse skin. The receptor protein was associated with the cell membrane. Following peripheral nerve injury sst2A-like immunoreactivity (LI) was decreased, and SST-LI increased in DRGs. sst2A-LI accumulated on the proximal and, more strongly, on the distal side of a sciatic nerve ligation. Fluorescence-labeled SST administered to a hind paw was internalized and retrogradely transported, indicating that a SST-sst2A complex may represent a retrograde signal. Internalization of sst2A was seen in DRG neurons after systemic treatment with the sst2 agonist octreotide (Oct), and in dorsal horn and DRG neurons after intrathecal administration. Some DRG neurons co-expressed sst2A and the neuropeptide Y Y1 receptor on the cell membrane, and systemic Oct caused co-internalization, hypothetically a sign of receptor heterodimerization. Oct treatment attenuated the reduction of pain threshold in a neuropathic pain model, in parallel suppressing the activation of p38 MAPK in the DRGs CONCLUSIONS: The findings highlight a significant and complex role of the SST system in pain signaling. The fact that the sst2A system is found also in human DRGs and spinal cord, suggests that sst2A may represent a potential pharmacologic target for treatment of neuropathic pain.
Subject(s)
Ganglia, Spinal/pathology , Receptors, Somatostatin/metabolism , Sciatica/metabolism , Sciatica/pathology , Sensory Receptor Cells/metabolism , Somatostatin/metabolism , Animals , Disease Models, Animal , Dose-Response Relationship, Drug , Female , Functional Laterality/genetics , Gene Expression Regulation/drug effects , Gene Expression Regulation/genetics , Glutamate Decarboxylase/genetics , Green Fluorescent Proteins/deficiency , Green Fluorescent Proteins/genetics , Humans , Hyperalgesia/drug therapy , Hyperalgesia/etiology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Middle Aged , Octreotide/therapeutic use , Oligopeptides/pharmacology , Pain Threshold/drug effects , Pain Threshold/physiology , Protein Transport/drug effects , Protein Transport/genetics , Receptors, Somatostatin/antagonists & inhibitors , Receptors, Somatostatin/deficiency , Receptors, Somatostatin/genetics , Sciatica/complications , Sciatica/drug therapy , Sensory Receptor Cells/drug effects , Somatostatin/geneticsABSTRACT
Let-7 microRNA is expressed in lower lever in a variety of human tumors and is involved in tumorigenesis. This study investigated the inhibitory effect of the let-7g microRNA on the expression of the HMGA2 gene in the fluorouracil (5-Fu)-resistant human hepatoma cell line Bel-7402/5-Fu, and the effect of let-7 g microRNA on drug sensitization in Bel-7402/5-Fu cells. Let-7 g microRNA and negative microRNA plasmids were constructed and transient transfected into Bel-7402/5-Fu cells. Expression levels of HMGA2 mRNA and protein in microRNA transient transfectants were clearly reduced as compared with negative microRNA transfectants and untreated cells. Flow cytometry revealed increased in S phase in let-7 g microRNA cells. dimethylthiazol-diphenyltetrazolium bromide (MTT) results indicated that microRNA transfectants had a higher cell inhibition rate than the negative vector or untreated cells after treatment with 0.13-13 microg/ml 5-Fu. In addition, cyclin A was down-regulated in the let-7 g transfectants cells.The results showed that let-7 g microRNA contributed to an increase of 5-Fu-induced cell cycle inhibit in human hepatoma cell and sensitized cells to 5-Fu, leading to increased the effectiveness of the drug in treating hepatoma cancer.
Subject(s)
Antimetabolites, Antineoplastic/pharmacology , Drug Resistance, Neoplasm/drug effects , Fluorouracil/pharmacology , MicroRNAs/pharmacology , Blotting, Western , Carcinoma, Hepatocellular/drug therapy , Cell Line, Tumor , Coloring Agents , Cyclin A/biosynthesis , Down-Regulation , Flow Cytometry , Genetic Vectors , HMGA2 Protein/antagonists & inhibitors , HMGA2 Protein/biosynthesis , Humans , Liver Neoplasms/drug therapy , Real-Time Polymerase Chain Reaction , Tetrazolium Salts , Thiazoles , TransfectionABSTRACT
The proprotein convertase subtilisin/kexin type 9 (PCSK9) belongs to a member of the proprotein convertase (PC) family, which is mainly secreted by the liver and plays a central role in lipid metabolism. Furthermore, PCSK9 plays a multifunctional role in promoting the inflammatory response, inducing cell apoptosis and pyroptosis and affecting tumor homeostasis. The brain is the organ with the richest lipid content. Incidentally, PCSK9 increased in many brain diseases, including brain injury and Alzheimer's disease (AD). Consequently, the relationship between PCSK9 and brain diseases has attracted increasing research interest. Amyloid beta (Aß) accumulation is the central and initial event in the pathogenesis of AD. This study focuses on the effects of PCSK9 on Aß accumulation in the brain via multiple modalities to explore the potential role of PCSK9 in AD, which is characterized by progressive loss of brain cells by increasing Aß accumulation. The study also explores the new mechanism by which PCSK9 is involved in the pathogenesis of AD, providing interesting and innovative guidance for the future of PCSK9-targeted therapy for AD.
ABSTRACT
This study was done to explore the role of microRNA-98 (miR-98) in cisplatin sensitization in human lung adenocarcinoma cell line. Differential expressions of miRNAs were analysed between cisplatin-resistant human lung adenocarcinoma cell line A549/DDP and its parental cell A549 by miRNAs microarray, of which 14 miRNAs were showed to be significantly (>2-fold) up-regulated and 8 miRNAs had marked down-regulation (<0.5-fold) in A549/DDP cells compared with in A549 cells. MiR-98, a member in the let-7 family, acts as a negative regulator in the expression of HMGA2 (high mobility group A2) oncogene, and it has been shown to have a nearly 3-fold decrease in A549/DDP cells. We found that elevated expression of miR-98 led to a higher sensitivity of A549/DDP cells to cisplatin, and the protein level of HMGA2, was clearly up-regulated in both A549/DDP and A549 cells by miR-98. Moreover, both Bcl-XL and Bcl-2, were down-regulated in the Pre-miR-98(TM) transfectants cells. We for the first time demonstrated that the expression of miR-98 increases cells spontaneous apoptosis and sensitizes cells to cisplatin at least in part via HMGA2 up-regulation. Our findings provided insight into some specific miRNAs in lung cancer as potential therapeutic targets.
Subject(s)
Antineoplastic Agents/pharmacology , Cisplatin/pharmacology , HMGA2 Protein/biosynthesis , MicroRNAs/pharmacology , Blotting, Western , Cell Line, Tumor , Coloring Agents , Drug Resistance, Neoplasm , Flow Cytometry , Genetic Vectors , HMGA2 Protein/genetics , Humans , In Situ Hybridization , Luciferases/metabolism , Proto-Oncogene Proteins c-bcl-2/biosynthesis , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Tetrazolium Salts , Thiazoles , Transfection , bcl-X Protein/biosynthesisABSTRACT
Background. Low-intensity transcranial ultrasound stimulation (TUS) could induce both immediate and long-lasting neuromodulatory effects in human brains. Interhemispheric imbalance at prefrontal or motor cortices generally associates with various cognitive decline in aging and mental disorders. However, whether TUS could modulate the interhemispheric balance of excitability in human brain remains unknown.Objective. This study aims to explore whether repetitive TUS (rTUS) intervention can modulate the interhemispheric balance of excitability between bilateral motor cortex (M1) in healthy subjects.Approach. Motor evoked potentials (MEPs) at bilateral M1 were measured at 15 min and 0 min before a 15 min active or sham rTUS intervention on left M1 and at 0 min, 15 min and 30 min after the intervention, and the Chinese version of brief neurocognitive test battery (C-BCT) was conducted before and after the intervention respectively. Cortical excitability was quantified by MEPs, and the long-lasting changes of MEP amplitude was used as an index of plasticity.Results. In the active rTUS group (n= 20), the ipsilateral MEP amplitude increased significantly compared with baselines and lasted for up to 30 min after intervention, while the contralateral MEP amplitude decreased lasting for 15 min, yielding increased laterality between bilateral MEPs. Furthermore, rTUS intervention induced changes in some C-BCT scores, and the changes of scores correlated with the changes of MEP amplitudes induced by rTUS intervention. The sham rTUS group (n= 20) showed no significant changes in MEPs and C-BCT scores. In addition, no participants reported any adverse effects during and after the rTUS intervention, and no obvious temperature increase appeared in skull or brain tissues in simulation.Significance. rTUS intervention modulated the plasticity of ipsilateral M1 and the interhemispheric balance of M1 excitability in human brain, and improved cognitive performance, suggesting a considerable potential of rTUS in clinical interventions.
Subject(s)
Mental Disorders , Motor Cortex , Humans , Motor Cortex/physiology , Transcranial Magnetic Stimulation/methods , Evoked Potentials, Motor/physiology , Functional Laterality/physiologyABSTRACT
The effect of antipsychotic medications is critical for the long-term outcome of symptoms and functions during first-episode psychosis (FEP). However, how brain functions respond to the antipsychotic treatment in the early stage of psychosis and its underlying neural mechanisms remain unclear. In this study, we explored the cross-sectional and longitudinal changes of regional homogeneity (ReHo), whole-brain functional connectivity, and network topological properties via resting-state functional magnetic resonance images. Thirty-two drug-naïve FEP patients and 30 matched healthy volunteers (HV) were included, where 23 patients were re-visited with effective responses after two months of antipsychotic treatment. Compared to HV, drug-naive patients demonstrated significantly different patterns of functional connectivity involving the right thalamus. These functional alterations mainly involved decreased ReHo, increased nodal efficiency in the right thalamus, and increased thalamic-sensorimotor-frontoparietal connectivity. In the follow-up analysis, patients after treatment showed reduced ReHo and nodal clustering in visual networks, as well as disturbances of visual-somatomotor and hippocampus-superior frontal gyrus connectivity. The longitudinal changes of ReHo in the visual cortex were associated with an improvement in general psychotic symptoms. This study provides new evidence regarding alterations in brain function linked to schizophrenia onset and affected by antipsychotic medications. Moreover, our results demonstrated that the functional alterations at baseline were not fully modulated by antipsychotic medications, suggesting that antipsychotic medications may reduce psychotic symptoms but limit the effects in regions involved in disease pathophysiology.