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1.
Acta Pharmacol Sin ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38538716

RESUMEN

Refractory wounds are a severe complication of diabetes mellitus that often leads to amputation because of the lack of effective treatments and therapeutic targets. The pathogenesis of refractory wounds is complex, involving many types of cells. Rho-associated protein kinase-1 (ROCK1) phosphorylates a series of substrates that trigger downstream signaling pathways, affecting multiple cellular processes, including cell migration, communication, and proliferation. The present study investigated the role of ROCK1 in diabetic wound healing and molecular mechanisms. Our results showed that ROCK1 expression significantly increased in wound granulation tissues in diabetic patients, streptozotocin (STZ)-induced diabetic mice, and db/db diabetic mice. Wound healing and blood perfusion were dose-dependently improved by the ROCK1 inhibitor fasudil in diabetic mice. In endothelial cells, fasudil and ROCK1 siRNA significantly elevated the phosphorylation of adenosine monophosphate-activated protein kinase at Thr172 (pThr172-AMPKα), the activity of endothelial nitric oxide synthase (eNOS), and suppressed the levels of mitochondrial reactive oxygen species (mtROS) and nitrotyrosine formation. Experiments using integrated bioinformatics analysis and coimmunoprecipitation established that ROCK1 inhibited pThr172-AMPKα by binding to receptor-interacting serine/threonine kinase 4 (RIPK4). These results suggest that fasudil accelerated wound repair and improved angiogenesis at least partially through the ROCK1/RIPK4/AMPK pathway. Fasudil may be a potential treatment for refractory wounds in diabetic patients.

2.
Acta Pharmacol Sin ; 45(2): 327-338, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37845344

RESUMEN

Tricyclic antidepressants (TCAs) are widely used to treat depression and anxiety-related mood disorders. But evidence shows that TCAs elevate blood glucose levels and inhibit insulin secretion, suggesting that TCAs are a risk factor, particularly for individuals with diabetes. Curcumin is a bioactive molecule from the rhizome of the Curcuma longa plant, which has shown both antidepressant and anti-diabetic activities. In the present study, we investigated the protective effect of curcumin against desipramine-induced apoptosis in ß cells and the underlying molecular mechanisms. In the mouse forced swimming test (FST), we found that lower doses of desipramine (5 and 10 mg/kg) or curcumin (2.5 mg/kg) alone did not affect the immobility time, whereas combined treatment with curcumin (2.5 mg/kg) and desipramine (5, 10 mg/kg) significantly decreased the immobility time. Furthermore, desipramine dose-dependently inhibited insulin secretion and elevated blood glucose levels, whereas the combined treatment normalized insulin secretion and blood glucose levels. In RIN-m5F pancreatic ß-cells, desipramine (10 µM) significantly reduced the cell viability, whereas desipramine combined with curcumin dose-dependently prevented the desipramine-induced impairment in glucose-induced insulin release, most effectively with curcumin (1 and 10 µM). We demonstrated that desipramine treatment promoted the cleavage and activation of Caspase 3 in RIN-m5F cells. Curcumin treatment inhibited desipramine-induced apoptosis, increased mitochondrial membrane potential and Bcl-2/Bax ratio. Desipramine increased the generation of reactive oxygen species, which was reversed by curcumin treatment. Curcumin also inhibited the translocation of forkhead box protein O1 (FOXO1) from the cytoplasm to the nucleus and suppressed the binding of A-kinase anchor protein 150 (AKAP150) to protein phosphatase 2B (PP2B, known as calcineurin) that was induced by desipramine. These results suggest that curcumin protects RIN-m5F pancreatic ß-cells against desipramine-induced apoptosis by inhibiting the phosphoinositide 3-kinase/AKT/FOXO1 pathway and the AKAP150/PKA/PP2B interaction. This study suggests that curcumin may have therapeutic potential as an adjunct to antidepressant treatment.


Asunto(s)
Curcumina , Ratones , Animales , Curcumina/farmacología , Desipramina/farmacología , Glucemia , Fosfatidilinositol 3-Quinasas/metabolismo , Apoptosis , Antidepresivos/farmacología
3.
BMC Complement Med Ther ; 23(1): 415, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978381

RESUMEN

BACKGROUND: Cardiovascular disease and cancer are the main causes of morbidity and mortality worldwide. Studies have shown that these two diseases may have some common risk factors. Atorvastatin is mainly used for the treatment of atherosclerosis in clinic. A large number of studies show that atorvastatin may produce anti-tumor activities. This study aimed to predict the common targets of atorvastatin against atherosclerosis and non-small cell lung cancer (NSCLC) based on network pharmacology. METHODS: The target genes of atherosclerosis and NSCLC were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. The disease-target-component model map and the core network were obtained using Cytoscape 3.7.1. The MTS and wound healing assay were used to detect the effect of atorvastatin on cell viability and migration of A549 cells. The expression of potential common target genes of atorvastatin against atherosclerosis and NSCLC were confirmed in A549 cells and lung cancer tissues of patients. RESULTS: We identified 15 identical pathogenic genes, and four of which (MMP9, MMP12, CD36, and FABP4) were considered as the key target genes of atorvastatin in anti-atherosclerosis and NSCLC. The MTS and wound healing assays revealed that atorvastatin decreased A549 cells migration significantly. Atorvastatin markedly decreased the expression of MMP9, MMP12, CD36, and FABP4 in A549 cells and patients were treated with atorvastatin. CONCLUSIONS: This study demonstrated 15 common pathogenic genes in both atherosclerosis and NSCLC. And verified that MMP 9, MMP 12, CD 36 and FABP 4 might be the common target genes of atorvastatin in anti-atherosclerosis and NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/uso terapéutico , Atorvastatina/farmacología , Atorvastatina/uso terapéutico , Metaloproteinasa 12 de la Matriz/uso terapéutico
4.
Ying Yong Sheng Tai Xue Bao ; 34(10): 2820-2826, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37897290

RESUMEN

From November 2021 to September 2022, we conducted four field surveys on macroinvertebrates and water environmental factors in Xinyang section of the Huaihe River main stream. We analyzed the structure and spatiotemporal distribution characteristics of the functional feeding groups of macroinvertebrates, and evaluated river water quality. A total of 73 macroinvertebrate species were collected in the basin, belonging to 42 families, 7 classes, and 3 phyla. The dominant species of macroinvertebrates changed significantly in different months, with Exopalaemon modestus being the absolute advantage species in the basin in July and September 2022. In different sampling months, the functional feeding group of macroinvertebrates was mainly dominated by shredders, accounting for 35.9%. The results of redundancy analysis showed that the main environmental factors affecting the distribution of functional feeding groups of macroinvertebrates varied across different months, with conductivity in February, temperature in July, and oxidation-reduction potential in September and November. The evaluation based on the biolo-gical index and Shannon index of macroinvertebrates indicated that water quality in the investigated section was at a light pollution level.


Asunto(s)
Invertebrados , Calidad del Agua , Humanos , Animales , Ecosistema , Ríos/química , Monitoreo del Ambiente/métodos
5.
Biochem Pharmacol ; 216: 115807, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37716621

RESUMEN

Small cell lung cancer (SCLC) is a highly lethal subtype of lung cancer with few therapeutic options; therefore, the identification of new targets and drugs with potent combination therapy is desirable. We previously screened BH3 mimetics from a natural product library, and in this study, we validated nobiletin as a BH3 mimetic. Specifically, we observed its combination potential and mechanism with vorinostat in SCLC in vitro and in vivo. The results showed that combination treatment with nobiletin and vorinostat reduced the proliferation of SCLC H82 cells and increased the levels of apoptotic proteins such as cleaved caspase-9 and cleaved PARP. The combination treatment increased LC3-II expression and induced autophagic cell death. In addition, this treatment significantly inhibited H82 cell xenograft SCLC tumor growth in nude mice. The combination treatment with nobiletin and vorinostat efficiently increased autophagy by inhibiting the PI3K-AKT-mTOR pathway and promoting dissociation of the BCL-2 and Beclin 1 complex, increasing the level of isolated Beclin 1 to stimulate autophagy. Molecular docking and surface plasmon resonance analysis showed that nobiletin stably bound to the BCL-2, BCL-XL and MCL-1 proteins with high affinity in a concentration-dependent manner. These results suggest that nobiletin is a BH3-only protein mimetic. Furthermore, the combination of nobiletin with vorinostat increased histone H3K9 and H3K27 acetylation levels in SCLC mouse tumor tissue and enhanced the expression of the BH3-only proteins BIM and BID. We conclude that nobiletin is a novel natural BH3 mimetic that can cooperate with vorinostat to induce apoptosis and autophagy in SCLC.


Asunto(s)
Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Humanos , Animales , Ratones , Vorinostat/farmacología , Vorinostat/uso terapéutico , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Beclina-1 , Ratones Desnudos , Fosfatidilinositol 3-Quinasas , Simulación del Acoplamiento Molecular , Apoptosis , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Autofagia , Línea Celular Tumoral
6.
Neurobiol Dis ; 187: 106293, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37709208

RESUMEN

Spastic paraplegia type 11 (SPG11) is a common autosomal recessive form of hereditary spastic paraplegia (HSP) characterized by the degeneration of cortical motor neuron axons, leading to muscle spasticity and weakness. Impaired lipid trafficking is an emerging pathology in neurodegenerative diseases including SPG11, though its role in axonal degeneration of human SPG11 neurons remains unknown. Here, we established a pluripotent stem cell-based SPG11 model by knocking down the SPG11 gene in human embryonic stem cells (hESCs). These stem cells were then differentiated into cortical projection neurons (PNs), the cell types affected in HSP patients, to examine axonal defects and cholesterol distributions. Our data revealed that SPG11 deficiency led to reduced axonal outgrowth, impaired axonal transport, and accumulated swellings, recapitulating disease-specific phenotypes. In SPG11-knockdown neurons, cholesterol was accumulated in lysosome and reduced in plasma membrane, revealing impairments in cholesterol trafficking. Strikingly, the liver-X-receptor (LXR) agonists restored cholesterol homeostasis, leading to the rescue of subsequent axonal defects in SPG11-deficient cortical PNs. To further determine the implication of impaired cholesterol homeostasis in SPG11, we examined the cholesterol distribution in cortical PNs generated from SPG11 disease-mutation knock-in hESCs, and observed a similar cholesterol trafficking impairment. Moreover, LXR agonists rescued the aberrant cholesterol distribution and mitigated the degeneration of SPG11 disease-mutated neurons. Taken together, our data demonstrate impaired cholesterol trafficking underlying axonal degeneration of SPG11 human neurons, and highlight the therapeutic potential of LXR agonists for SPG11 through restoring cholesterol homeostasis.


Asunto(s)
Paraplejía Espástica Hereditaria , Humanos , Paraplejía Espástica Hereditaria/genética , Paraplejía Espástica Hereditaria/metabolismo , Proteínas/metabolismo , Neuronas/metabolismo , Mutación , Colesterol/metabolismo , Hígado/patología
7.
Sensors (Basel) ; 23(14)2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37514563

RESUMEN

This paper presents a metasurface-based linear-to-circular polarization converter with a flexible structure for conformal and wearable applications. The converter consists of nested S- and C-shaped split ring resonators in the unit cell and can convert linearly polarized incident waves into left-handed circularly polarized ones at 12.4 GHz. Simulation results show that the proposed design has a high polarization conversion rate and efficiency at the operating frequency. Conformal tests are also conducted to evaluate the performance under curvature circumstances. A minor shift in the operating frequency is observed when the converter is applied on a sinusoidal wavy surface.

8.
Zhongguo Gu Shang ; 36(4): 308-12, 2023 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-37087617

RESUMEN

OBJECTIVE: To explore treatment strategy for complex Schatzker Ⅳ tibial plateau fracture. METHODS: Forty-one patients with complex Schatzker type Ⅳ tibial plateau fractures were treated from January 2016 to January 2021, including 28 males and 13 females, aged from 19 to 65 years old with an average of (35.3±19.8) years old. Individualized treatment plan was developed according to preoperative imaging characteristics, medial surgical approach was mainly combined with other auxiliary incisions. Posteromedial inverted L approach was used in 18 patients, posteromedial approach and anterolateral extended approach in 19 patients, and posteromedial approach with anterolateral and lateral condylar osteotomy in 4 patients. Articular surface and facture healing were observed, range of knee joint motion was measured at 12 months after opertaion, and function of knee joint was evaluated by Lysholm scoring system. RESULTS: Forty-one patients were followed up for 12 to 26 months with an average of (13.3±6.8) months. Twenty-nine patients and 10 patients were obtained complete fracture healing at 6 and 12 months after operation respectively, and fracture healing time was 4 to 13 months with an average of (5.0±3.7) months. Two patients occurred posterior medial internal fixation failure and varus deformity of knee joint, and the fracture healed and varus deformity was corrected after the second operation. Range of knee joint motion was (118±29) °, and Lysholm score was(83.0±16.0) points. CONCLUSION: Individualized treatment should be reasonably selected for complex Schatzker Ⅳ tibial plateau fractures, the characteristics of lateral plateau fractures are an important reference for selecting surgical approaches, the effective fixation of posteromedial bone blocks should be pay full attention, and the overall treatment results are satisfied.


Asunto(s)
Fracturas de la Tibia , Fracturas de la Meseta Tibial , Masculino , Femenino , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Adolescente , Placas Óseas , Fracturas de la Tibia/cirugía , Resultado del Tratamiento , Articulación de la Rodilla/cirugía , Fijación Interna de Fracturas/métodos , Estudios Retrospectivos
9.
Orphanet J Rare Dis ; 18(1): 72, 2023 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-37024986

RESUMEN

BACKGROUND: Biallelic mutations in CYP27A1 and CYP7B1, two critical genes regulating cholesterol and bile acid metabolism, cause cerebrotendinous xanthomatosis (CTX) and hereditary spastic paraplegia type 5 (SPG5), respectively. These rare diseases are characterized by progressive degeneration of corticospinal motor neuron axons, yet the underlying pathogenic mechanisms and strategies to mitigate axonal degeneration remain elusive. METHODS: To generate induced pluripotent stem cell (iPSC)-based models for CTX and SPG5, we reprogrammed patient skin fibroblasts into iPSCs by transducing fibroblast cells with episomal vectors containing pluripotency factors. These patient-specific iPSCs, as well as control iPSCs, were differentiated into cortical projection neurons (PNs) and examined for biochemical alterations and disease-related phenotypes. RESULTS: CTX and SPG5 patient iPSC-derived cortical PNs recapitulated several disease-specific biochemical changes and axonal defects of both diseases. Notably, the bile acid chenodeoxycholic acid (CDCA) effectively mitigated the biochemical alterations and rescued axonal degeneration in patient iPSC-derived neurons. To further examine underlying disease mechanisms, we developed CYP7B1 knockout human embryonic stem cell (hESC) lines using CRISPR-cas9-mediated gene editing and, following differentiation, examined hESC-derived cortical PNs. Knockout of CYP7B1 resulted in similar axonal vesiculation and degeneration in human cortical PN axons, confirming a cause-effect relationship between gene deficiency and axonal degeneration. Interestingly, CYP7B1 deficiency led to impaired neurofilament expression and organization as well as axonal degeneration, which could be rescued with CDCA, establishing a new disease mechanism and therapeutic target to mitigate axonal degeneration. CONCLUSIONS: Our data demonstrate disease-specific lipid disturbances and axonopathy mechanisms in human pluripotent stem cell-based neuronal models of CTX and SPG5 and identify CDCA, an established treatment of CTX, as a potential pharmacotherapy for SPG5. We propose this novel treatment strategy to rescue axonal degeneration in SPG5, a currently incurable condition.


Asunto(s)
Células Madre Pluripotentes Inducidas , Paraplejía Espástica Hereditaria , Xantomatosis Cerebrotendinosa , Humanos , Ácido Quenodesoxicólico/farmacología , Ácido Quenodesoxicólico/uso terapéutico , Ácido Quenodesoxicólico/metabolismo , Xantomatosis Cerebrotendinosa/genética , Neuronas/metabolismo , Neuronas/patología , Paraplejía Espástica Hereditaria/metabolismo , Ácidos y Sales Biliares , Paraplejía/metabolismo
10.
JAMA Intern Med ; 183(3): 272-275, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36716009

RESUMEN

This randomized clinical trial assesses the long-term effect of vigorous and moderate exercise on incident diabetes over a 10-year follow-up after a 12-month exercise intervention.


Asunto(s)
Diabetes Mellitus , Obesidad , Adulto , Humanos , Estudios de Seguimiento , Obesidad/epidemiología , Obesidad/terapia , Ejercicio Físico , Diabetes Mellitus/epidemiología , Diabetes Mellitus/terapia , Terapia por Ejercicio
11.
Diabetes Ther ; 14(1): 167-178, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36454378

RESUMEN

INTRODUCTION: Patients with diabetes are confronted with numerous obstacles to achieve adequate glycemic control during hospitalization. The aim of this study was to explore the risk factors associated with glycemic control in hospitalized patients with type 2 diabetes mellitus (T2DM) treated with continuous subcutaneous insulin infusion (CSII). METHODS: This cross-sectional study included 5223 patients hospitalized with T2DM in a tertiary hospital in Xiamen (China) between January 2017 and December 2019. All patients were managed according to established protocols for glycemic monitoring and insulin pump treatment regimens. Demographic information and clinical profiles were collected from electronic health records. Multiple linear regression analysis was used to identify the risk factors associated with glycemic control. RESULTS: Among the 5223 hospitalized patients with T2DM receiving CSII therapy, 55.2% achieved their ideal blood glucose level (3.9-10.0 mmol/L), 44.5% experienced hyperglycemia (> 10.0 mmol/L), and 0.3% experienced hypoglycemia (< 3.9 mmol/L) during their hospitalization. Multivariate analyses showed that among inpatients with T2DM, older age, male gender, higher low-density lipoprotein-cholesterol (LDL-C) level, lower C-peptide (C-P) level, lower body mass index (BMI), longer duration of diabetes, previous insulin prescriptions, nephropathy, and retinopathy were factors more likely to be associated with a blood glucose level in the hyperglycemic range (P < 0.05). We also observed that among hospitalized patients with T2DM, those with lower BMI, lower C-P, lower LDL-C, longer disease duration, and previous insulin prescriptions were more likely to correlate with a higher proportion of hypoglycemia range (all P < 0.05). CONCLUSION: Older age, male gender, lower BMI, lower C-P, higher LDL-C, previous insulin prescriptions, longer duration of diabetes, nephropathy, and retinopathy may be risk factors for a higher proportion of hyperglycemic events in hospitalized patients with T2DM under CSII therapy. Furthermore, lower BMI, lower C-P, lower LDL-C, longer duration of diabetes, and previous insulin prescriptions were found to be important factors for a higher proportion of hypoglycemic events. Evaluating the clinical features, comorbidities, and complications of hospitalized patients is essential to achieve reasonable glycemic control.

12.
Brain ; 145(11): 4016-4031, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-35026838

RESUMEN

Hereditary spastic paraplegias are characterized by lower limb spasticity resulting from degeneration of long corticospinal axons. SPG11 is one of the most common autosomal recessive hereditary spastic paraplegias, and the SPG11 protein spatacsin forms a complex with the SPG15 protein spastizin and heterotetrameric AP5 adaptor protein complex, which includes the SPG48 protein AP5Z1. Using the integration-free episomal method, we established SPG11 patient-specific induced pluripotent stem cells (iPSCs) from patient fibroblasts. We differentiated SPG11 iPSCs, as well as SPG48 iPSCs previously established, into cortical projection neurons and examined protective effects by targeting mitochondrial dynamics using P110, a peptide that selectively inhibits mitochondrial fission GTPase Drp1. P110 treatment mitigates mitochondrial fragmentation, improves mitochondrial motility, and restores mitochondrial health and ATP levels in SPG11 and SPG48 neurons. Neurofilament aggregations are increased in SPG11 and SPG48 axons, and these are also suppressed by P110. Similarly, P110 mitigates neurofilament disruption in both SPG11 and SPG48 knockdown cortical projection neurons, confirming the contribution of hereditary spastic paraplegia gene deficiency to subsequent neurofilament and mitochondrial defects. Strikingly, neurofilament aggregations in SPG11 and SPG48 deficient neurons double stain with ubiquitin and autophagy related proteins, resembling the pathological hallmark observed in SPG11 autopsy brain sections. To confirm the cause-effect relationship between the SPG11 mutations and disease phenotypes, we knocked-in SPG11 disease mutations to human embryonic stem cells (hESCs) and differentiated these stem cells into cortical projection neurons. Reduced ATP levels and accumulated neurofilament aggregations along axons are observed, and both are mitigated by P110. Furthermore, rescue experiment with expression of wild-type SPG11 in cortical projection neurons derived from both SPG11 patient iPSCs and SPG11 disease mutation knock-in hESCs leads to rescue of mitochondrial dysfunction and neurofilament aggregations in these SPG11 neurons. Finally, in SPG11 and SPG48 long-term cultures, increased release of phosphoNF-H, a biomarker for nerve degeneration, is significantly reduced by inhibiting mitochondrial fission pharmacologically using P110 and genetically using Drp1 shRNA. Taken together, our results demonstrate that impaired mitochondrial dynamics underlie both cytoskeletal disorganization and axonal degeneration in SPG11 and SPG48 neurons, highlighting the importance of targeting these pathologies therapeutically.


Asunto(s)
Paraplejía Espástica Hereditaria , Humanos , Paraplejía Espástica Hereditaria/patología , Dinámicas Mitocondriales , Neuronas/metabolismo , Mutación , Adenosina Trifosfato/metabolismo , Proteínas/genética
13.
Methods Mol Biol ; 2549: 69-83, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33772460

RESUMEN

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegias (HSPs). HSPs are a large heterogeneous group of neurodegenerative diseases characterized by axonopathy involving the long corticospinal tract. How axons of these cortical projection neurons specifically degenerate in HSPs remains largely unclear partially due to the lack of human models to monitor the dynamic process of axonal degeneration. With the development of induced pluripotent stem cell (iPSC) technology, patient-specific iPSCs are successfully generated from HSP patients, providing a unique paradigm to study the axonal degeneration in patient-derived neurons in live cultures. In this chapter, we will summarize the procedures to examine axonal defects in iPSC models of HSPs and discuss the challenges and future applications in order to rescue axonal degeneration in HSPs.


Asunto(s)
Células Madre Pluripotentes Inducidas , Paraplejía Espástica Hereditaria , Axones , Humanos , Neuronas , Paraplejía Espástica Hereditaria/genética
15.
Front Mol Neurosci ; 14: 727552, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34602978

RESUMEN

Charcot-Marie-Tooth (CMT) disease is one of the most common genetically inherited neurological disorders and CMT type 2A (CMT 2A) is caused by dominant mutations in the mitofusin-2 (MFN2) gene. MFN2 is located in the outer mitochondrial membrane and is a mediator of mitochondrial fusion, with an essential role in maintaining normal neuronal functions. Although loss of MFN2 induces axonal neuropathy, the detailed mechanism by which MFN2 deficiency results in axonal degeneration of human spinal motor neurons remains largely unknown. In this study, we generated MFN2-knockdown human embryonic stem cell (hESC) lines using lentivirus expressing MFN2 short hairpin RNA (shRNA). Using these hESC lines, we found that MFN2 loss did not affect spinal motor neuron differentiation from hESCs but resulted in mitochondrial fragmentation and dysfunction as determined by live-cell imaging. Notably, MFN2-knockodwn spinal motor neurons exhibited CMT2A disease-related phenotypes, including extensive perikaryal inclusions of phosphorylated neurofilament heavy chain (pNfH), frequent axonal swellings, and increased pNfH levels in long-term cultures. Importantly, MFN2 deficit impaired anterograde and retrograde mitochondrial transport within axons, and reduced the mRNA and protein levels of kinesin and dynein, indicating the interfered motor protein expression induced by MFN2 deficiency. Our results reveal that MFN2 knockdown induced axonal degeneration of spinal motor neurons and defects in mitochondrial morphology and function. The impaired mitochondrial transport in MFN2-knockdown spinal motor neurons is mediated, at least partially, by the altered motor proteins, providing potential therapeutic targets for rescuing axonal degeneration of spinal motor neurons in CMT2A disease.

16.
Gastroenterol Rep (Oxf) ; 9(4): 313-322, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34567563

RESUMEN

BACKGROUND: Chronic hepatitis B (CHB) patients have a high virological relapse rate after cessation of nucleos(t)ide analog (NA) treatment, but the clinical outcome remains unclear. This study aimed to investigate the 96-week clinical outcomes and the risk factors for relapse in CHB after cessation of NAs. METHODS: This study was a prospective trial; 74 eligible patients were enrolled. The patients underwent NA cessation and follow-up according to the 2012 Asian Pacific Association for the Study of the Liver Guideline. Symptoms, biochemical (aspartate aminotransferase [AST], alanine aminotransferase [ALT], total bilirubin, urea nitrogen, creatinine), virological data (hepatitis B surface antigen [HBsAg], hepatitis B e antigen [HBeAg], hepatitis B e antibody [HBeAb], hepatitis B virus [HBV] DNA levels), and color Doppler ultrasound examination results were recorded and analysed. RESULTS: After NA cessation, 19 cases were HBsAg-negative without relapse during the 96-week follow-up. Of the 55 cases of HBsAg-positive after cessation, four types of clinical outcomes were observed. Twelve patients had no relapse during the 96-week follow-up (type A, 21.8%), 7 patients underwent virological relapses but spontaneously had a non-virological relapse (type B, 12.7%), 10 patients maintained virological relapse (type C, 18.2%), and 26 patients turned to clinical relapse, received NA retreatment, and achieved ALT normalization and negative conversion of HBV DNA within 12 months (type D, 47.3%). The 2-year overall cumulative rates of virological and clinical relapses were 58.1% and 24.3%, respectively. Independent factors associated with virological relapse were duration of negative HBV DNA, EOT (end of treatment) HBsAg, and original status of HBeAg. The EOT HBsAg was also an independent factor for clinical relapse. CONCLUSIONS: There are four types of clinical outcomes in patients with CHB after cessation of NA treatment. Further research is needed to explore the mechanism of different clinical outcomes. The EOT HBsAg level is an independent factor associated with both virological and clinical relapse.

17.
Pharmaceuticals (Basel) ; 14(6)2021 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-34204831

RESUMEN

Motor neurons are large projection neurons classified into upper and lower motor neurons responsible for controlling the movement of muscles. Degeneration of motor neurons results in progressive muscle weakness, which underlies several debilitating neurological disorders including amyotrophic lateral sclerosis (ALS), hereditary spastic paraplegias (HSP), and spinal muscular atrophy (SMA). With the development of induced pluripotent stem cell (iPSC) technology, human iPSCs can be derived from patients and further differentiated into motor neurons. Motor neuron disease models can also be generated by genetically modifying human pluripotent stem cells. The efficiency of gene targeting in human cells had been very low, but is greatly improved with recent gene editing technologies such as zinc-finger nucleases (ZFN), transcription activator-like effector nucleases (TALEN), and CRISPR-Cas9. The combination of human stem cell-based models and gene editing tools provides unique paradigms to dissect pathogenic mechanisms and to explore therapeutics for these devastating diseases. Owing to the critical role of several genes in the etiology of motor neuron diseases, targeted gene therapies have been developed, including antisense oligonucleotides, viral-based gene delivery, and in situ gene editing. This review summarizes recent advancements in these areas and discusses future challenges toward the development of transformative medicines for motor neuron diseases.

18.
Sensors (Basel) ; 21(8)2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33921476

RESUMEN

A reconfigurable gm-boosted, image-rejected downconversion mixer is presented in this paper using the SiGe 8 HP technology. The proposed mixer operates within 0.9-13.5 GHz that is suitable for software-defined radio applications. The conversion mixer comprises of resistive biased radio frequency (RF) section, double balanced Gilbert cell mixer core sections divided as per I and Q stages for image-rejection purpose, inductively peaked gm-boosting section and tunable filter section, respectively. In comparison to previous works in the scientific literature, the design shows enhanced conversion gain (CG), noise figure (NF), and image-rejection ratio (IRR). For the entire band of operation, the mixer attains a good return loss |S11| of <-10 dB. Additionally, the design accomplishes an excellent CG of 22 dB, NF of 2.5 dB, and an image-rejection ratio of 30.2 dB at maximum frequency. Finally, a third-order intercept point (IP3) of -3.28 dBm and 1 dB compression point (CP1) of -13 dBm, respectively, shows moderate linearity performance.

19.
Heliyon ; 7(2): e06200, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33585707

RESUMEN

Investigating and classifying sentiments of social media users (e.g., positive, negative) towards an item, situation, and system are very popular among researchers. However, they rarely discuss the underlying socioeconomic factor associations for such sentiments. This study attempts to explore the factors associated with positive and negative sentiments of the people about reopening the economy, in the United States (US) amidst the COVID-19 global crisis. It takes into consideration the situational uncertainties (i.e., changes in work and travel patterns due to lockdown policies), economic downturn and associated trauma, and emotional factors such as depression. To understand the sentiment of the people about the reopening economy, Twitter data was collected, representing the 50 States of the US and Washington D.C, the capital city of the US. State-wide socioeconomic characteristics of the people (e.g., education, income, family size, and employment status), built environment data (e.g., population density), and the number of COVID-19 related cases were collected and integrated with Twitter data to perform the analysis. A binary logit model was used to identify the factors that influence people toward a positive or negative sentiment. The results from the logit model demonstrate that family households, people with low education levels, people in the labor force, low-income people, and people with higher house rent are more interested in reopening the economy. In contrast, households with a high number of family members and high income are less interested in reopening the economy. The accuracy of the model is reasonable (i.e., the model can correctly classify 56.18% of the sentiments). The Pearson chi-squared test indicates that this model has high goodness-of-fit. This study provides clear insights for public and corporate policymakers on potential areas to allocate resources, and directional guidance on potential policy options they can undertake to improve socioeconomic conditions, to mitigate the impact of pandemic in the current situation, and in the future as well.

20.
Acta Neuropathol Commun ; 8(1): 214, 2020 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-33287888

RESUMEN

Hereditary spastic paraplegias (HSPs) are caused by a length-dependent axonopathy of long corticospinal neurons, but how axons of these cortical projection neurons (PNs) degenerate remains elusive. We generated isogenic human pluripotent stem cell (hPSC) lines for two ATL1 missense mutations associated with SPG3A, the most common early-onset autosomal dominant HSP. In hPSC-derived cortical PNs, ATL1 mutations resulted in reduced axonal outgrowth, impaired axonal transport, and accumulated axonal swellings, recapitulating disease-specific phenotypes. Importantly, ATL1 mutations dysregulated proteolipid gene expression, reduced lipid droplet size in astrocytes, and unexpectedly disrupted cholesterol transfer from glia to neurons, leading to cholesterol deficiency in SPG3A cortical PNs. Applying cholesterol or conditioned medium from control astrocytes, a major source of cholesterol in the brain, rescued aberrant axonal transport and swellings in SPG3A cortical PNs. Furthermore, treatment with the NR1H2 agonist GW3965 corrected lipid droplet defects in SPG3A astrocytes and promoted cholesterol efflux from astrocytes, leading to restoration of cholesterol levels and rescue of axonal degeneration in SPG3A cortical PNs. These results reveal a non-cell autonomous mechanism underlying axonal degeneration of cortical PNs mediated by impaired cholesterol homeostasis in glia.


Asunto(s)
Astrocitos/metabolismo , Corteza Cerebral/metabolismo , Colesterol/metabolismo , Metabolismo de los Lípidos/fisiología , Neuronas/metabolismo , Tractos Piramidales/metabolismo , Paraplejía Espástica Hereditaria/metabolismo , Astrocitos/efectos de los fármacos , Astrocitos/patología , Axones/efectos de los fármacos , Axones/metabolismo , Axones/patología , Benzoatos/farmacología , Bencilaminas/farmacología , Corteza Cerebral/citología , Proteínas de Unión al GTP/genética , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Receptores X del Hígado/agonistas , Proteínas de la Membrana/genética , Neuronas/efectos de los fármacos , Neuronas/patología , Células Madre Pluripotentes , Tractos Piramidales/citología , Paraplejía Espástica Hereditaria/genética , Paraplejía Espástica Hereditaria/patología
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