ABSTRACT
BACKGROUND: Hyperglycemia-induced neuroinflammation significantly contributes to diabetic neuropathic pain (DNP), but the underlying mechanisms remain unclear. OBJECTIVE: To investigate the role of Sirt3, a mitochondrial deacetylase, in hyperglycemia-induced neuroinflammation and DNP and to explore potential therapeutic interventions. METHOD AND RESULTS: Here, we found that Sirt3 was downregulated in spinal dorsal horn (SDH) of diabetic mice by RNA-sequencing, which was further confirmed at the mRNA and protein level. Sirt3 deficiency exacerbated hyperglycemia-induced neuroinflammation and DNP by enhancing microglial aerobic glycolysis in vivo and in vitro. Overexpression of Sirt3 in microglia alleviated inflammation by reducing aerobic glycolysis. Mechanistically, high-glucose stimulation activated Akt, which phosphorylates and inactivates FoxO1. The inactivation of FoxO1 diminished the transcription of Sirt3. Besides that, we also found that hyperglycemia induced Sirt3 degradation via the mitophagy-lysosomal pathway. Blocking Akt activation by GSK69093 or metformin rescued the degradation of Sirt3 protein and transcription inhibition of Sirt3 mRNA, which substantially diminished hyperglycemia-induced inflammation. Metformin in vivo treatment alleviated neuroinflammation and diabetic neuropathic pain by rescuing hyperglycemia-induced Sirt3 downregulation. CONCLUSION: Hyperglycemia induces metabolic reprogramming and inflammatory activation in microglia through the regulation of Sirt3 transcription and degradation. This novel mechanism identifies Sirt3 as a potential drug target for treating DNP.
Subject(s)
Diabetes Mellitus, Experimental , Diabetic Neuropathies , Down-Regulation , Glycolysis , Hyperglycemia , Mice, Inbred C57BL , Microglia , Sirtuin 3 , Animals , Sirtuin 3/metabolism , Sirtuin 3/genetics , Mice , Glycolysis/drug effects , Glycolysis/physiology , Down-Regulation/drug effects , Down-Regulation/physiology , Hyperglycemia/metabolism , Microglia/metabolism , Microglia/drug effects , Male , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/complications , Diabetic Neuropathies/metabolism , Inflammation/metabolism , Neuroinflammatory Diseases/metabolism , Neuroinflammatory Diseases/etiology , Metformin/pharmacologyABSTRACT
Neuropathic pain (NP) is associated with astrocytes activation induced by nerve injury. Reactive astrocytes, strongly induced by central nervous system damage, can be classified into A1 and A2 types. Vitexin, a renowned flavonoid compound, is known for its anti-inflammatory and analgesic properties. However, its role in NP remains unexplored. This study aims to investigate the effects of vitexin on astrocyte polarization and its underlying mechanisms. A mouse model of NP was established, and primary astrocytes were stimulated with sphingosine-1-phosphate (S1P) to construct a cellular model. The results demonstrated significant activation of spinal astrocytes on days 14 and 21. Concurrently, reactive astrocytes predominantly differentiated into the A1 type. Western blot analysis revealed an increase in A1 astrocyte-associated protein (C3) and a decrease in A2 astrocyte-associated protein (S100A10). Serum S1P levels increased on days 14 and 21, alongside a significant upregulation of Sphingosine-1-phosphate receptor 1 (S1PR1) mRNA expression and elevated expression of chemokines. In vitro, stimulation with S1P inhibited the Phosphatidylinositol 3-kinase and protein kinase B (PI3K/Akt) signaling pathway and autophagy flux, promoting polarization of astrocytes towards the A1 phenotype while suppressing the polarization of A2 astrocytes. Our findings suggest that vitexin, acting on astrocytes but not microglia, attenuates S1P-induced downregulation of PI3K/Akt signaling, restores autophagy flux in astrocytes, regulates A1/A2 astrocyte ratio, and reduces chemokine and S1P secretion, thereby alleviating neuropathic pain caused by nerve injury.
ABSTRACT
Neuropathic pain (NPP) is a common type of chronic pain. Glial cells, including astrocytes (AS), are believed to play an important role in the progression of NPP. AS cells can be divided into various types based on their expression profiles, among which A1 and A2 types have clear functions. A1-type AS cells are neurotoxic, while A2-type AS cells exert neuroprotective functions. Some types of lysophosphatidic acid receptors (LPAR) have been shown to play a role in NPP. However, it remains unclear how AS cells and LPAR6 affect the occurrence and progression of NPP. In this study, we established a mouse model of chronic constriction injury (CCI) to simulate NPP. It was found that the expression of LPAR6 in AS cells of the spinal dorsal horn was increased in the CCI model, and the thresholds of mechanical and thermal pain were elevated after knocking out LPAR6, indicating that LPAR6 and AS cells participated in the occurrence of NPP. The experiment involved culturing primary AS cells and knocking down LPAR6 by Lentivirus. The results showed that the NF-κB signal pathway was activated and the number of A1-type AS cells increased in the CCI model. However, LPAR6 knockdown inhibited the NF-κB signal pathway and A1-type AS cells. The results of the mRNA sequencing and immunoprecipitation test indicate an interaction between LPAR6 and ROCK2. Inhibiting ROCK2 by Y-27632 increased mechanical and thermal pain thresholds and alleviated NPP at the molecular level. The study presents evidence that LPAR6 activates the NF-κB pathway through ROCK2 and contributes to the progression of NPP by increasing A1-type AS and decreasing A2-type AS. This suggests that LPAR6 could be a potential therapeutic target for alleviating NPP. Clinical applications that are successful can offer new therapeutic options, enhance the quality of life for patients, and potentially uncover new mechanisms for pain modulation.
ABSTRACT
Microglia induced chronic inflammation is the critical pathology of Neuropathic pain (NP). Metabolic reprogramming of macrophage has been intensively reported in various chronic inflammation diseases. However, the metabolic reprogramming of microglia in chronic pain remains to be elusive. Here, we reported that immuno-metabolic markers (HIF-1α, PKM2, GLUT1 and lactate) were related with increased expression of PRMT6 in the ipsilateral spinal cord dorsal horn of the chronic construction injury (CCI) mice. PRMT6 deficiency or prophylactic and therapeutic intrathecal administration of PRMT6 inhibitor (EPZ020411) ameliorated CCI-induced NP, inflammation and glycolysis in the ipsilateral spinal cord dorsal horn. PRMT6 knockout or knockdown inhibited LPS-induced inflammation, proliferation and glycolysis in microglia cells. While PRMT6 overexpression exacerbated LPS-induced inflammation, proliferation and glycolysis in BV2 cells. Recent research revealed that PRMT6 could interact with and methylate HIF-1α, which increased HIF-1α protein stability. In sum, increased expression of PRMT6 exacerbates NP progress by increasing glycolysis and neuroinflammation through interacting with and stabilizing HIF-1α in a methyltransferase manner, which outlines novel pathological mechanism and drug target for NP.
Subject(s)
Microglia , Neuralgia , Mice , Animals , Microglia/metabolism , Lipopolysaccharides/pharmacology , Lipopolysaccharides/metabolism , Inflammation/metabolism , Neuralgia/metabolism , GlycolysisABSTRACT
Chronic varicella zoster virus (VZV) infection induced neuroinflammatory condition is the critical pathology of post-herpetic neuralgia (PHN). The immune escape mechanism of VZV remains elusive. As to mice have no VZV infection receptor, herpes simplex virus type 1 (HSV-1) infection is a well established PHN mice model. Transcriptional expression analysis identified that the protein arginine methyltransferases 6 (Prmt6) was upregulated upon HSV-1 infection, which was further confirmed by immunofluorescence staining in spinal dorsal horn. Prmt6 deficiency decreased HSV-1-induced neuroinflammation and PHN by enhancing antiviral innate immunity and decreasing HSV-1 load in vivo and in vitro. Overexpression of Prmt6 in microglia dampened antiviral innate immunity and increased HSV-1 load. Mechanistically, Prmt6 methylated and inactivated STING, resulting in reduced phosphorylation of TANK binding kinase-1 (TBK1) and interferon regulatory factor 3 (IRF3), diminished production of type I interferon (IFN-I) and antiviral innate immunity. Furthermore, intrathecal or intraperitoneal administration of the Prmt6 inhibitor EPZ020411 decreased HSV-1-induced neuroinflammation and PHN by enhancing antiviral innate immunity and decreasing HSV-1 load. Our findings revealed that HSV-1 escapes antiviral innate immunity and results in PHN by upregulating Prmt6 expression and inhibiting the cGAS-STING pathway, providing novel insights and a potential therapeutic target for PHN.
Subject(s)
Herpesvirus 1, Human , Membrane Proteins , Neuralgia, Postherpetic , Nucleotidyltransferases , Protein-Arginine N-Methyltransferases , Up-Regulation , Animals , Protein-Arginine N-Methyltransferases/metabolism , Protein-Arginine N-Methyltransferases/genetics , Protein-Arginine N-Methyltransferases/antagonists & inhibitors , Mice , Membrane Proteins/metabolism , Membrane Proteins/genetics , Nucleotidyltransferases/metabolism , Nucleotidyltransferases/genetics , Neuralgia, Postherpetic/metabolism , Neuralgia, Postherpetic/immunology , Mice, Inbred C57BL , Immunity, Innate , Humans , Mice, Knockout , Male , Interferon Regulatory Factor-3/metabolism , Interferon Regulatory Factor-3/genetics , Herpes Simplex/immunology , Microglia/metabolism , Microglia/immunology , Protein Serine-Threonine KinasesABSTRACT
The objective of this study was to analyze the effects on cell viability, apoptosis, and cell cycle of non-small cell lung cancer (NSCLC) A549 cells after intervention with Agrimonia pilosa (AP) and investigate Agrimonia pilosa anti-tumor activity in vitro. Meanwhile, liquid chromatography mass spectrometry (LC-MS) metabolomics technology was used to analyze the changes of cellular metabolites and metabolic pathways. The results of this study will provide a theoretical and experimental basis for investigating the mechanism of the effect of Agrimonia pilosa on non-small cell lung cancer A549 cells. The results showed that the cell nucleus of A549 cells crumpled and apoptosis occurred with the increase of drug concentration. The survival rate of the cells decreased, and the inhibition rate reached 21.5% and 91.74% under the low and high dose conditions, respectively. Lactate dehydrogenase (LDH) content increased (P < 0.05). Metabolomics results showed significant differences in metabolism between groups, thirty-three distinct metabolites including LysoPC(24:0/0:0), LysoPC(17:0/0:0) and PC(O-40:5) were deduced. The pathway enrichment showed that the Agrimonia pilosa plays an anti-tumor role mainly by regulating the metabolism of glycerophosphate and purine in A549 cells, in which the effect on glycerophosphate metabolism pathway was most significant. The results of combined pharmacodynamics suggested that Agrimonia pilosa might induce apoptosis and inhibit the growth of A549 cells by regulating LysoPC(24:0/0:0), LysoPC(17:0/0:0) and PC(O-40:5) metabolites in A549 cells.
ABSTRACT
Introduction: Myocardial infarction (MI) is a fatal manifestation of coronary heart disease, and its underlying mechanism is still largely unknown. Lipid levels and composition alterations predict the risk of MI complications. Glycerophospholipids (GPLs) are important bioactive lipids and play a crucial role in the development of cardiovascular diseases. However, the metabolic changes in the GPLs profile during post-MI injury remain unknown. Methods: In the current study, we constructed a classic MI model by ligating the left anterior descending branch and assessed the alterations in both plasma and myocardial GPLs profiles during the reparative phase post-MI by liquid chromatography-tandem mass spectrometry analysis. Results: We found that myocardial GPLs, but not plasma GPLs, were markedly changed after MI injury. Importantly, MI injury is associated with decreased phosphatidylserine (PS) levels. Consistently, the expression of phosphatidylserine synthase 1 (PSS1), which catalyzes the formation of PS from its substrate phosphatidylcholine, was significantly reduced in heart tissues after MI injury. Furthermore, oxygen-glucose deprivation (OGD) inhibited PSS1 expression and reduced PS levels in primary neonatal rat cardiomyocytes, while overexpression of PSS1 restored the inhibition of PSS1 and the reduction in PS levels caused by OGD. Moreover, overexpression of PSS1 abrogated, whereas knockdown of PSS1 aggravated, OGD-induced cardiomyocyte apoptosis. Conclusions: Our findings revealed that GPLs metabolism was involved in the reparative phase post-MI, and cardiac decreased PS levels, resulting from inhibition of PSS1, are important contributor to the reparative phase post-MI. PSS1 overexpression represents a promising therapeutic strategy to attenuate MI injury.
ABSTRACT
The pro-inflammatory phenotype of microglia usually induces neuroinflammatory reactions in neuropathic pain. Glycometabolism shift to glycolysis can promote the pro-inflammatory phenotype transition of microglia. The omics data analysis suggest a critical role for Lyn dysregulation in neuropathic pain. The present study aimed at exploring the mechanism of Lyn-mediated glycolysis enhancement of microglia in neuropathic pain. Neuropathic pain model was established by chronic constriction injury (CCI), then pain thresholds and Lyn expression were measured. Lyn inhibitor Bafetinib and siRNA-lyn knockdown were administrated intrathecally to evaluate the effects of Lyn on pain thresholds, glycolysis and interferon regulatory factor 5 (IRF5) nuclear translocation of microglia in vivo and in vitro. ChIP was carried out to observe the binding of transcription factors SP1, PU.1 to glycolytic gene promoters by IRF5 knockdown. Finally, the relationship between glycolysis and pro-inflammatory phenotype transition of microglia was evaluated. CCI led to the upregulation of Lyn expression and glycolysis enhancement in microglia of spinal dorsal horn. Bafetinib or siRNA-lyn knockdown intrathecally alleviated pain hyperalgesia, suppressed glycolysis enhancement and inhibited nuclear translocation of IRF5 in CCI mice. Also, IRF5 promoted the binding of transcription factors SP1, PU.1 to glycolytic gene promoters, and then the enhanced glycolysis facilitated the proliferation and pro-inflammatory phenotype transition of microglia and contributed to neuropathic pain. Lyn-mediated glycolysis enhancement of microglia contributes to neuropathic pain through facilitating IRF5 nuclear translocation in spinal dorsal horn.
Subject(s)
Neuralgia , Spinal Cord , Animals , Mice , Interferon Regulatory Factors/metabolism , Microglia/metabolism , Neuralgia/metabolism , Rats, Sprague-Dawley , Spinal Cord/metabolism , Spinal Cord Dorsal Horn/metabolism , RatsABSTRACT
Background: Understanding the incidence pattern of cutaneous reactions is crucial for promoting COVID-19 vaccination. We aimed to report the global incidence pattern of, and factors associated with common cutaneous reactions related to COVID-19 vaccination in real-world settings. Methods: We searched five databases (PubMed, Web of Science, Embase, CNKI, and Wanfang) from inception to May 13, 2022, for studies reporting the incidence of common cutaneous reactions related to COVID-19 vaccines in real-world settings. The outcomes were the systematic skin reactions (rash and urticaria) and the local injection site reactions (pain, swelling, redness, and erythema). We conducted random-effects meta-analyses and explored associated factors using multi-step statistical analyses. Results: We included 35 studies and assessed 2 549 968 participants from 23 countries. The pooled incidence of overall systemic skin reactions was 3.8% (95% confidence interval (CI) = 2.4%-5.5%) with short duration (about one week). Specifically, the pooled incidence rates of rash and urticaria were 3.0% (95% CI = 2.1%-3.9%) and 1.1% (95% CI = 0.7%-1.5%), respectively. For overall local injection site reactions, the pooled incidence was 72.4% (95% CI = 65.7%-78.7%) with short duration (1 to 4.5 days). Except for local pain (72.2%, 95% CI = 65.3%-78.5%), other localized reactions had low incidence, including swelling (13.3%, 95% CI = 9.5%-17.7%), redness (11.5%, 95% CI = 5.7%-19.0%), and erythema (5.8%, 95% CI = 0.7%-15.4%). Geographically, different distribution patterns were observed for these reactions. Regarding associated factors, mRNA vaccines showed lower incidence of urticaria (P < 0.001). Asia population showed higher incidence of urticaria (P < 0.001). We observed lower incidence rates of overall local injection site reactions and pain among inactivated vaccines (P < 0.001). We found no significant difference among reactions between the first and the second dose of vaccines. Conclusions: We examined the global incidence pattern of common cutaneous reactions related to COVID-19 vaccination and found low incidence and short duration of systemic skin reactions and local injection site reactions (except for pain); discrepancies in these reactions were observed across different vaccine types. The cutaneous side effects related to COVID-19 vaccination do not seem to cause concern. Registration: PROSPERO: CRD42021258012.
Subject(s)
COVID-19 Vaccines , COVID-19 , Exanthema , Urticaria , Vaccines , Humans , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Incidence , Injection Site Reaction/epidemiology , Injection Site Reaction/etiology , Pain , Vaccination/adverse effectsABSTRACT
Objective To explore the range of normal female pelvic diameter lines in Tibetan nationality. Methods The subjects were Tibetan nationality female who underwent pelvic CT examination in the Radiology Department from January 2016 to December 2019 at the General Hospital of the Tibet Military Region of PLA. Ninty-six samples between the ages of 22 and 65 years, with an average age (46.06±11.42)years were recruited. Mimics 19.0 software was used to construct the digital three-dimensional model of pelvis, and to measure transverse diameter(TD), obstetric conjugate(OC), interspinous distance(ISD), sagittal midpelvic diameter(SMD), intertuberous distance(ITD), sagittal outlet diameter(SOD),diagonal conjugate diameter(DCD),sacrum length(SL), penal height(PH).Analysis of variance was used to compare different age groups, and Pearson correlation analysis was used to analyze the relationship between age and pelvic diameter. Results The linear measurement of TD was (132.08±6.15) mm, OC was (112.44±9.43) mm, ISD was (107.30±8.70), SMD was (129.06±7.73) mm, ITD was (123.02±12.08) mm, SOD was (118.80±8.87) mm, DCD was (127.49±9.80) mm, SL was (102.56±10.88) mm and PH was (36.57±4.57) mm.Cluster analysis showed that Lhasa Tibetans were closest to Uygurs. Conclusion The close clustering relationship between Tibetans and Uygurs in Lhasa suggests that there is a possibility of gene exchange between Tibetans and Uygurs in Hotan area in ancient times. The pelvic diameter of Tibetan women in Lhasa has changed significantly. Narrower OC, SL and PH make the pelvis flat, which is more and more detrimental to natural childbirth.
ABSTRACT
The study aimed to examine the effects of virtual reality (VR) technology-based phase I cardiac rehabilitation (CR) program in elderly coronary heart disease (CHD) patients after percutaneous coronary intervention (PCI). Thirty-six cases of elderly CHD patients who underwent PCI in the First Affiliated Hospital of Chongqing Medical University from June 2022 to April 2023 were recruited by convenience sampling method. The patients were randomly assigned by means of random digital table method to two study groups: control group (n = 18), which received conventional nursing intervention after PCI, and experimental group (n = 18), which received a combined program of conventional nursing intervention together with CR program based on VR technology. The 6 min walk test (6MWT), Simple Physical Performance Battery (SPPB), SF-36 scale, Hospital Anxiety and Depression Scale (HADS) and Impact of Events Scale-Revised (IES-R) were tested before and after rehabilitation. Moreover, the incidence of major adverse cardiovascular events (MACE) was recorded at 3 months after PCI. After VR-based CR, the 6MWT distance and SPPB scores of patients in the experimental group were higher than those in control group (P < 0.05). The HADS scores and IES-R scores of the patients in the experimental group were lower than those in control group (P < 0.01), and the difference in SF-36 scale scores was not statistically significant between two groups (P > 0.05). The incidence of MACE was not significantly different at 3 months after PCI (P > 0.05). These results suggest that VR-based phase I CR program mitigates the degree of PCI postoperative stress, anxiety, and depression in elderly CHD patients, however, enhances the resistance to fatigue and does not increase the risk of adverse cardiac events, suggesting it is a safe intervention.
Subject(s)
Aged , Humans , Anxiety , Cardiac Rehabilitation/methods , Coronary Disease/surgery , Percutaneous Coronary Intervention/adverse effects , Virtual RealityABSTRACT
Objective: To investigate the feasibility of only surgical resection for nasal vestibular squamous cell carcinoma and the efficacy of perforator flap of ipsilateral nasolabial sulcus in repairing postoperative defects. Methods: The clinical data of 8 cases with squamous cell carcinoma of the nasal vestibule who admitted to Department of Facial Plastic and Reconstructive Surgery, Eye & ENT Hospital, Fudan University were analyzed, including 6 males and 2 females, aged from 38 to 75 years. The tumor of the nasal vestibule was eradicated in time after making definite diagnosis of lesions, then the perforators flap of the ipsilateral nasolabial sulcus was used for repairment, without performing further chemotherapy or radiotherapy after surgery. The tumor recurrence, facial appearance, nostril form, donor area scar, nasal ventilation function, and cutaneous sensation were evaluated after surgery. Descriptive analysis was used in this research. Results: There were 2 cases of stage T1 and 6 cases of stage T2 in 8 cases. After 32 to 45 months of following-up, no recurrence accurred and all the flaps survived well. However, there was about 2 mm necrosis of the transplanted flap in the lateral foot of the alar in one case, which was healed well by carrying out wound care after 10 d. And the dark color flap was occurred in another case, showing the flap's backflow trouble, yet it was improved with addressing timely during 5 d postoperation. Pincusion-like deformity of the transplanted flap occurred in 4 cases (50%), which subsided gradually after 6 months. The morphology of the anterior nostril was altered in 4 cases (50%), but there was no ventilation trouble and no need for addressment in any case. The postoperative facial appearance was rated as excellentor good with hidden scar in the donor site, and the sensation of the transplanted flaps was indistinct from the surrounding tissue after 3 months. Conclusions: Surgical resection of nasal vestibular squamous cell carcinoma with tumor stage T1-2 is a feasible treatment. And it is the one of the best reconstructive methods of the perforator flap of the ipsilateral nasolabial sulcus to repair the deformities after the surgery.
Subject(s)
Male , Female , Humans , Perforator Flap/transplantation , Cicatrix/surgery , Neoplasm Recurrence, Local/surgery , Plastic Surgery Procedures , Carcinoma, Squamous Cell/surgery , Skin Transplantation/methods , Treatment OutcomeABSTRACT
Spinal cord injury (SCI) is a devastating trauma characterized by serious neuroinflammation and permanent neurological dysfunction. However, the molecular mechanism of SCI remains unclear, and few effective medical therapies are available at present. In this study, multiple bioinformatics methods were used to screen out novel targets for SCI, and the mechanism of these candidates during the progression of neuroinflammation as well as the therapeutic effects were both verified in a rat model of traumatic SCI. As a result, CASP4, IGSF6 and IL1R1 were identified as the potential diagnostic and therapeutic targets for SCI by computational analysis, which were enriched in NF-κB and IL6-JAK-STATA3 signaling pathways. In the injured spinal cord, these three signatures were up-regulated and closely correlated with NLRP3 inflammasome formation and gasdermin D (GSDMD) -induced pyroptosis. Intrathecal injection of inhibitors of IL1R1 or CASP4 improved the functional recovery of SCI rats and decreased the expression of these targets and inflammasome component proteins, such as NLRP3 and GSDMD. This treatment also inhibited the pp65 activation into the nucleus and apoptosis progression. In conclusion, our findings of the three targets shed new light on the pathogenesis of SCI, and the use of immunosuppressive agents targeting these proteins exerted anti-inflammatory effects against spinal cord inflammation by inhibiting NF-kB and NLRP3 inflammasome activation, thus blocking GSDMD -induced pyroptosis and immune activation.
Subject(s)
Inflammasomes , Spinal Cord Injuries , Animals , Inflammasomes/metabolism , NF-kappa B/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Pyroptosis , Rats , Rats, Sprague-Dawley , Spinal Cord Injuries/metabolismABSTRACT
BACKGROUND: Chronic inflammatory pain significantly reduces the quality of life and lacks effective interventions. In recent years, human umbilical cord mesenchymal stem cells (huc-MSCs)-derived exosomes have been used to relieve neuropathic pain and other inflammatory diseases as a promising cell-free therapeutic strategy. However, the therapeutic value of huc-MSCs-derived exosomes in complete Freund's adjuvant (CFA)-induced inflammatory pain remains to be confirmed. In this study, we investigated the therapeutic effect and related mechanisms of huc-MSCs-derived exosomes in a chronic inflammatory pain model. METHODS: C57BL/6J male mice were used to establish a CFA-induced inflammatory pain model, and huc-MSCs-derived exosomes were intrathecally injected for 4 consecutive days. BV2 microglia cells were stimulated with lipopolysaccharide (LPS) plus adenosine triphosphate (ATP) to investigate the effect of huc-MSCs-derived exosomes on pyroptosis and autophagy. Bioinformatic analysis and rescue experiments were used to demonstrate the role of miR-146a-5p/ TRAF6 in regulating pyroptosis and autophagy. Western blotting, RT-qPCR, small interfering RNA and Yo-Pro-1 dye staining were performed to investigate the related mechanisms. RESULTS: Huc-MSCs-derived exosomes alleviated mechanical allodynia and thermal hyperalgesia in CFA-induced inflammatory pain. Furthermore, huc-MSCs-derived exosomes attenuated neuroinflammation by increasing the expression of autophagy-related proteins (LC3-II and beclin1) and inhibiting the activation of NLRP3 inflammasomes in the spinal cord dorsal horn. In vitro, NLRP3 inflammasome components (NLRP3, caspase1-p20, ASC) and gasdermin D (GSDMD-F, GSDMD-N) were inhibited in BV2 cells pretreated with huc-MSCs-derived exosomes. Western blot and Yo-Pro-1 dye staining demonstrated that 3-MA, an autophagy inhibitor, weakened the protective effect of huc-MSCs-derived exosomes on BV2 cell pyroptosis. Importantly, huc-MSCs-derived exosomes transfected with miR-146a-5p mimic promoted autophagy and inhibited BV2 cell pyroptosis. TRAF6, as a target gene of miR-146a-5p, was knocked down via small-interfering RNA, which increased pyroptosis and inhibited autophagy. CONCLUSION: Huc-MSCs-derived exosomes attenuated inflammatory pain via miR-146a-5p/TRAF6, which increased the level of autophagy and inhibited pyroptosis.
Subject(s)
Exosomes , MicroRNAs , Animals , Autophagy , Exosomes/metabolism , Humans , Male , Mice , Mice, Inbred C57BL , MicroRNAs/genetics , MicroRNAs/metabolism , Microglia/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Pain , Pyroptosis , Quality of Life , TNF Receptor-Associated Factor 6/genetics , TNF Receptor-Associated Factor 6/metabolismABSTRACT
Neuropathic pain is characterized by hyperalgesia and allodynia. Inflammatory response is conducive to tissue recovery upon nerve injury, but persistent and exaggerated inflammation is detrimental and participates in neuropathic pain. Synaptic transmission in the nociceptive pathway, and particularly the balance between facilitation and inhibition, could be affected by inflammation, which in turn is regulated by glial cells. Importantly, glycometabolism exerts a vital role in the inflammatory process. Glycometabolism reprogramming of inflammatory cells in neuropathic pain is characterized by impaired oxidative phosphorylation in mitochondria and enhanced glycolysis. These changes induce phenotypic transition of inflammatory cells to promote neural inflammation and oxidative stress in peripheral and central nervous system. Accumulation of lactate in synaptic microenvironment also contributes to synaptic remodeling and central sensitization. Previous studies mainly focused on the glycometabolism reprogramming in peripheral inflammatory cells such as macrophage or lymphocyte, little attention was paid to the regulation effects of glycometabolism reprogramming on the inflammatory responses in glial cells. This review summarizes the evidences for glycometabolism reprogramming in peripheral inflammatory cells, and presents a small quantity of present studies on glycometabolism in glial cells, expecting to promote the exploration in glycometabolism in glial cells of neuropathic pain.
Subject(s)
Neuralgia , Central Nervous System/metabolism , Humans , Hyperalgesia/metabolism , Inflammation/metabolism , Neuralgia/metabolism , Neuroglia/metabolismABSTRACT
Chronic pain, such as persistent inflammatory pain, remains a public health problem that has no effective treatment at present. Bromodomain-containing protein 4 (BRD4) inhibition, induced by JQ1 injection or BRD4 knockdown, has been used to attenuate inflammatory pain; However, it remains elusive whether BRD4 aggravates inflammatory pain by regulating inflammasome. Western blot and immunofluorescence staining showed that BRD4 expression increased after administration of complete Freund's adjuvant (CFA) and reached its peak on day 3. Immunofluorescence staining showed that BRD4 was mainly colocalized with NeuN-positive neurons in the spinal cord, which was accompanied by upregulation of inflammasome component proteins, such as NLRP3, gasdermin D, and caspase-1. JQ1 was intrathecally injected into mice 1 h before CFA administration, and the mechanical and thermal hyperalgesia levels were measured on days 1, 3, and 7 after CFA administration. CFA-induced inflammatory pain, paw inflammation, and swelling were attenuated by pre-treatment with JQ1. To our knowledge, this study was the first to prove that NLRP3 inflammasome-induced neuronal pyroptosis participates in inflammatory pain. BRD4 inhibition decreased the expression of pyroptosis-related proteins by inhibiting the activation of NF-κB signaling pathway, both in vivo and in vitro. Taken together, BRD4 inhibition exerted analgesic and anti-inflammatory effects against inflammatory pain by inhibiting NF-κB and inflammasome activation, which protected neural cells from pyroptosis.
Subject(s)
Azepines/pharmacology , Inflammasomes/metabolism , Nuclear Proteins/antagonists & inhibitors , Pain/drug therapy , Pyroptosis/drug effects , Transcription Factors/antagonists & inhibitors , Triazoles/pharmacology , Animals , Cell Line , Disease Models, Animal , Freund's Adjuvant/administration & dosage , Hyperalgesia/drug therapy , Inflammation/physiopathology , Injections, Spinal , Male , Mice , Mice, Inbred C57BL , NF-kappa B/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Nuclear Proteins/metabolism , Signal Transduction , Transcription Factors/metabolismABSTRACT
Electromyography (EMG) signals can be used for clinical diagnosis and biomedical applications. It is very important to reduce noise and to acquire accurate signals for the usage of the EMG signals in biomedical engineering. Since EMG signal noise has the time-varying and random characteristics, the present study proposes an adaptive Kalman filter (AKF) denoising method based on an autoregressive (AR) model. The AR model is built by applying the EMG signal, and the relevant parameters are integrated to find the state space model required to optimally estimate AKF, eliminate the noise in the EMG signal, and restore the damaged EMG signal. To be specific, AR autoregressive dynamic modeling and repair for distorted signals are affected by noise, and AKF adaptively can filter time-varying noise. The denoising method based on the self-learning mechanism of AKF exhibits certain capabilities to achieve signal tracking and adaptive filtering. It is capable of adaptively regulating the model parameters in the absence of any prior statistical knowledge regarding the signal and noise, which is aimed at achieving a stable denoising effect. By comparatively analyzing the denoising effects exerted by different methods, the EMG signal denoising method based on the AR-AKF model is demonstrated to exhibit obvious advantages.
Subject(s)
Electromyography/statistics & numerical data , Algorithms , Biomedical Engineering , Computational Biology , Healthy Volunteers , Humans , Male , Models, Statistical , Signal Processing, Computer-Assisted , Signal-To-Noise Ratio , Wavelet AnalysisABSTRACT
Macroautophagy/autophagy, an evolutionarily conserved process, plays an important role in the regulation of immune inflammation and nervous system homeostasis. However, the exact role and mechanism of autophagy in pain is still unclear. Here, we showed that impaired autophagy flux mainly occurred in astrocytes during the maintenance of neuropathic pain. No matter the stage of neuropathic pain induction or maintenance, activation of autophagy relieved the level of pain, whereas inhibition of autophagy aggravated pain. Moreover, the levels of neuroinflammation and reactive oxygen species (ROS) were increased or decreased following autophagy inhibition or activation. Further study showed that inhibition of autophagy slowed the induction, but increased the maintenance of neuroinflammatory responses, which could be achieved by promoting the binding of TRAF6 (TNF receptor-associated factor 6) to K63 ubiquitinated protein, and increasing the levels of p-MAPK8/JNK (mitogen-activated protein kinase 8) and nuclear factor of kappa light polypeptide gene enhancer in B cells (NFKB/NF-κB). Impaired autophagy also reduced the protective effect of astrocytes on neurons against ROS stress because of the decrease in the level of glutathione released by astrocytes, which could be improved by activating the NFE2L2/NRF2 (nuclear factor, erythroid derived 2, like 2) pathway. We also demonstrated that simultaneous activation of autophagy and the NFE2L2 pathway further relieved pain, compared to activating autophagy alone. Our study provides an underlying mechanism by which autophagy participates in the regulation of neuropathic pain, and a combination of autophagy and NFE2L2 activation may be a new treatment approach for neuropathic pain.Abbreviation: 3-MA: 3-methyladenine; 8-OHdG: 8-hydroxydeoxy-guanosine; ACTB: actin, beta; AMPAR: alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor; ATG: autophagy-related; CAMK2/CaMKII: calcium/calmodulin-dependent protein kinase II; CCL7: chemokine (C-C motif) ligand 7; CGAS: cyclic GMP-AMP synthase; CQ: chloroquine; GABA: gamma-aminobutyrate; GCLC: glutamate-cysteine ligase, catalytic subunit; GFAP: glial fibrillary acidic protein; GSH: glutathione; HMOX1/HO-1: heme oxygenase 1; KEAP1: kelch-like ECH-associated protein 1; MAP1LC3/LC3-II: microtubule-associated protein 1 light chain 3 beta (phosphatidylethanolamine-conjugated form); MAPK: mitogen-activated protein kinase; MAPK1/ERK: mitogen-activated protein kinase 1; MMP2: matrix metallopeptidase 2; MAPK8/JNK: mitogen-activated protein kinase 8; MAPK14/p38: mitogen-activated protein kinase 14; NFE2L2/NRF2: nuclear factor, erythroid derived 2, like 2; NFKB/NF-κB: nuclear factor of kappa light polypeptide gene enhancer in B cells; ROS: reactive oxygen species; SLC12A5: solute carrier family 12, member 5; SNL: spinal nerve ligation; TLR4: toll-like receptor 4; TRAF6: TNF receptor-associated factor; TRP: transient receptor potential.
Subject(s)
Autophagy , Neuralgia , Autophagy/physiology , Humans , Kelch-Like ECH-Associated Protein 1/metabolism , Macroautophagy , NF-E2-Related Factor 2/metabolismABSTRACT
Aberrant sphingolipid metabolism contributes to cardiac pathophysiology. Emerging evidence found that an increased level of ceramide during the inflammatory phase of post-myocardial infarction (MI) served as a biomarker and was associated with cardiac dysfunction. However, the alternation of the sphingolipid profile during the reparative phase after MI is still not fully understood. Using a mouse model of the left anterior descending ligation that leads to MI, we performed metabolomics studies to assess the alternations of both plasma and myocardial sphingolipid profiles during the reparative phase post-MI. A total number of 193 sphingolipid metabolites were detected. Myocardial sphingolipids but not plasma sphingolipids showed marked change after MI injury. Ceramide-1-phosphates, which were accumulated after MI, contributed highly to the difference in sphingolipid profiles between groups. Consistently, the expression of ceramide kinase, which phosphorylates ceramides to generate ceramide-1-phosphates, was upregulated in heart tissue after MI injury. Our findings revealed the altering sphingolipid metabolism during the reparative phase post-MI and highlighted the potential role of ceramide kinase/ceramide-1-phosphate in ischemic heart disease.
ABSTRACT
BACKGROUND & AIMS: Omega-3 polyunsaturated fatty acid (ω-3 PUFA) have been reported to have beneficial cardiovascular effects, but its mechanism of protection against acute myocardial infarction (AMI) who are under guideline-based therapy is not fully understood. Here, we used a metabolomic approach to systematically analyze the eicosanoid metabolites induced by ω-3 PUFA supplementation and investigated the underlying mechanisms. METHODS: Participants with AMI after successful percutaneous coronary intervention were randomized to 3 months of 2 g daily ω-3 PUFA and guideline-adjusted therapy (n = 30, ω-3 therapy) or guideline-adjusted therapy alone (n = 30, Usual therapy). Functional PUFA-derived eicosanoids in plasma were profiled by metabolomics. Clinical and laboratory tests were obtained before and 3 months after baseline and after the study therapy. RESULTS: By intent-to-treat analysis, the content of 11-HDoHE, 20-HDoHE and 16,17-EDP and that of epoxyeicosatetraenoic acids (EEQs), derived from docosahexaenoic acid and eicosapentaenoic acid, respectively, were significantly higher with ω-3 group than Usual therapy, whereas that of prostaglandin J2 (PGJ2) and leukotriene B4, derived from arachidonic acid, was significantly decreased. As compared with Usual therapy, ω-3 PUFA therapy significantly reduced levels of triglycerides (-6.3%, P < 0.05), apolipoprotein B (-4.9%, P < 0.05) and lipoprotein(a) (-37.0%, P < 0.05) and increased nitric oxide level (62.2%, P < 0.05). In addition, the levels of these variables were positively correlated with change in 16,17-EDP and EEQs content but negatively with change in PGJ2 content. CONCLUSIONS: ω-3 PUFA supplementation may improve lipid metabolism and endothelial function possibly by affecting eicosanoid metabolic status at a systemic level during convalescent healing after AMI. CLINICAL TRIAL REGISTRATION: URL: http://www.chictr.org.cn. Unique identifier: ChiCTR1900025859.