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Animals defend a target level for their fundamental needs, including food, water, and sleep. Deviation from the target range, or "setpoint," triggers motivated behaviors to eliminate that difference. Whether and how the setpoint itself is encoded remains enigmatic for all motivated behaviors. Employing a high-throughput feeding assay in Drosophila, we demonstrate that the protein intake setpoint is set to different values in male, virgin female, and mated female flies to meet their varying protein demands. Leveraging this setpoint variability, we found, remarkably, that the information on the intake setpoint is stored within the protein hunger neurons as the resting membrane potential. Two RFamide G protein-coupled receptor (GPCR) pathways, by tuning the resting membrane potential in opposite directions, coordinately program and adjust the protein intake setpoint. Together, our studies map the protein intake setpoint to a single trackable physiological parameter and elucidate the cellular and molecular mechanisms underlying setpoint determination and modulation.
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Ischemic stroke has been demonstrated to cause an imbalance of gut microbiota. However, the change in gut microbiota-mediated bile acids (BAs) metabolites remains unclear. Here, we observed a decrease in gut microbiota-mediated BAs, especially ursodeoxycholic acid (UDCA), in the serum of stroke patients as well as in the intestine, serum and brain of stroke mice. Restoration of UDCA could decrease the area of infarction and improve the neurological function and cognitive function in mice in association with inhibition of NLRP3-related pro-inflammatory cytokines through TGR5/PKA pathway. Furthermore, knocking out TGR5 and inhibiting PKA activity reduce the protective effect of UDCA. Taken together, our results suggest that microbiota-mediated UDCA plays an important role in alleviating inflammatory responses and might be a promising therapeutic target in ischemic stroke.
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Microbioma Gastrointestinal , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Humanos , Camundongos , Ácidos e Sais Biliares , Inflamação , Microglia/metabolismo , Ácido Ursodesoxicólico/metabolismoRESUMO
OBJECTIVE: This multicentre study aimed to assess the early and midterm outcomes of physician modified fenestrated endografts (PMEGs) for endovascular aortic arch repair in zone 0. METHODS: Between 2018 and 2022, a retrospective study was conducted in three centres of consecutive patients undergoing endovascular aortic arch repair in zone 0 with PMEGs. Endpoints included technical success, 30 day mortality rate, major adverse events, secondary interventions, stent stability, target vessel patency, and overall survival. RESULTS: A total of 54 patients (mean age 63 years; 45 males) with aortic arch pathology were included, comprising aortic dissections (n = 32; 59%) and aortic arch aneurysms (n = 22; 41%). Technical success was 98%. One patient died from stroke within 30 days. Major adverse events included stroke (n = 4; 7%), retrograde type A dissection (RTAD) (n = 3; 6%), and acute kidney injury (n = 2; 4%). During a median follow up of 12 months, there were two deaths (4%) of unknown cause at one month and 1.5 months, and no aortic related death. Type Ia, type Ic, and type IIIc endoleaks were observed in two (4%), three (6%), and two (4%) patients, respectively. No vessel stenosis was observed. Re-intervention was required in 10 patients (19%). Estimates of overall survival, freedom from secondary intervention, and freedom from target vessel instability at one year were 94.2% (standard error [SE] 3.3%), 81.8% (SE 6.0%), and 92.0% (SE 4.5%), respectively. CONCLUSION: This study has demonstrated the efficacy of PMEGs for zone 0 endovascular aortic arch repair, with acceptable technical success and mortality rates. Stroke, RTAD, and re-intervention rates remain a concern for endovascular therapy. A larger population and long term outcomes are required to assess the safety and durability of this technique as a beneficial choice for endovascular aortic arch repair in specialised centres.
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Aorta Torácica , Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Prótese Vascular , Procedimentos Endovasculares , Desenho de Prótese , Stents , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Procedimentos Endovasculares/mortalidade , Estudos Retrospectivos , Aorta Torácica/cirurgia , Aorta Torácica/diagnóstico por imagem , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/métodos , Implante de Prótese Vascular/mortalidade , Idoso , Resultado do Tratamento , Aneurisma da Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/mortalidade , Aneurisma da Aorta Torácica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Dissecção Aórtica/mortalidade , Dissecção Aórtica/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Fatores de TempoRESUMO
BACKGROUND: This study aimed to examine the outcomes of open surgery techniques involving sacotomy and suturing of the feeding vessels in patients with aneurysm sac expansion after endovascular aneurysm repair (EVAR). METHODS: Fourteen consecutive patients treated with sacotomy and suturing of feeding vessels for expanding aneurysm sacs with type II endoleaks following EVAR, between January 2018 and December 2022, were retrospectively included. All patients underwent preoperative digital subtraction angiography, and attempts were made to embolize the thick feeding vessels to reduce intraoperative bleeding. Age, sex, comorbidities, clinical presentation, aneurysm sac increase, morbidity, mortality, and follow-up were recorded. RESULTS: The median age of the patients was 72.89 ± 5.13 years old, and 13 (92.9%) patients were male. The sac size at the time of the open procedure was 107.89 ± 22.58 mm, and the extent of sac growth at the time of the open procedure was 37.50 ± 18.29 mm. The initial technical success rate of laparotomy and open ligation of the culprit arteries causing type II endoleaks was 92.9% (13/14). Among the patients, 5 (35.7%) had been treated with interventional embolization before the open procedure. One endograft was removed and replaced by a bifurcated Dacron graft because of distal dislocation in one patient. All patients recovered, and no deaths were recorded postoperatively. No patients had an eventful postoperative course or any subsequent graft-related complications during follow-up. CONCLUSIONS: Open surgical repair involving sacotomy and suturing of the feeding vessels appeared to have good outcomes in the treatment of patients with aneurysm sac expansion caused by type II endoleaks after EVAR. Preoperative embolization of feeding vessels can thus effectively reduce intraoperative bleeding.
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Aneurisma da Aorta Abdominal , Embolização Terapêutica , Endoleak , Correção Endovascular de Aneurisma , Aneurisma Ilíaco , Idoso , Feminino , Humanos , Masculino , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Prótese Vascular , Embolização Terapêutica/efeitos adversos , Endoleak/etiologia , Endoleak/prevenção & controle , Correção Endovascular de Aneurisma/efeitos adversos , Aneurisma Ilíaco/cirurgia , Aneurisma Ilíaco/diagnóstico por imagem , Estudos Retrospectivos , Fatores de Risco , Técnicas de Sutura/efeitos adversos , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: This study aimed to evaluate the outcomes of physician-modified endografts (PMEGs) for the treatment of thoracic aortic pathologies involving the aortic arch. METHODS: A retrospective single-center study was performed on consecutive patients with thoracic aortic pathologies treated by PMEGs between February 2018 and May 2022. Data on baseline characteristics, operative procedure, and follow-up information were collected. The endpoints included technical success, complications, mortality, overall survival, re-intervention, and target vessel instability. RESULTS: This study comprised 173 patients (mean age=58±13, range=28-83, 148 men) with thoracic aortic pathologies, including 44 thoracic aortic aneurysms, 113 aortic dissections (9 type A, 4 residual type A, 75 type B, 32 non-A non-B), 3 aortic intramural hematomas, and 13 penetrating aortic ulcers. Thirty-five of the patients had PMEGs with 3 fenestrations, 32 had 2 fenestrations, and 106 had 1 single fenestration. Technical success was 98% (170/173), and the 30-day mortality was 2% (3/173). Perioperative complications included stroke (n=3, 2%), retrograde type A dissection (RTAD; n=3, 2%) and renal injury (n=3, 2%). Seven deaths (4%) were noted during a median follow-up of 11 (range=1-52) months. Eleven cases of re-intervention were stent-related. There were 5 type Ia endoleaks (3%), 2 type III endoleaks (1%) from the innominate artery (IA), and 3 type Ic endoleaks (2%) from the left subclavian arteries. One case of IA stent-graft (SG) stenosis was noted because of mural thrombus. Estimate rates of overall survival, freedom from secondary intervention, and freedom from target vessel instability at 2 years were 93.4% (95% confidence interval [CI]=88.7%-98.1%), 80.7% (95% CI=73.3%-88.1%), and 89.0% (95% CI=80.4%-97.6%), respectively. CONCLUSIONS: Physician-modified endografts showed promising immediate therapeutic results in the treatment of thoracic aortic pathologies involving the aortic arch. Our study demonstrates that the technique is feasible and produces acceptable results. Long-term outcomes are required for further refinement of this technical approach to confirm technical success and durability over time as a valuable option for endovascular aortic arch repair in specialized centers. CLINICAL IMPACT: Our short- and mid-term outcomes of physician-modified endografts in 173 patients showed promising results compared to other branched/fenestrated techniques and backed up the endovascular repair of the aortic arch. Meanwhile, the technical expertise pointed out in our manuscript, including preloaded guidewire, diameter-reducing wire and inner mini-cuffs, provided reference and technical guidance for our peers. Most importantly, it demonstrated that the PMEG, as a device whose components were all commercially available, might be a better option for emergency surgery and for centers who had no access to custom-made devices.
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BACKGROUND AND OBJECTIVES: Frozen shoulder (FS) is characterized by pain and significant loss of active and passive shoulder motion. Strengthening exercises are among the standard exercises used for FS. Neuromuscular exercise (NME) effectively improved pain and the range of motion in shoulder. However, no prior research has looked into the effects of NME compared to strengthening exercises in FS rehabilitation. The aim of the present study was to evaluate the effects of NME compared to strengthening exercises on pain and active range of motion (AROM) in individuals with idiopathic frozen shoulder. METHODS: Forty individuals with idiopathic frozen shoulder were randomly assigned to either the experimental group (NME with regular physical therapy, n = 20) or the control group (strengthening exercises with regular physical therapy, n = 20). In both groups, the interventions were performed once a day, 5 days a week for 8 weeks. Pain scores on the visual analogue scale (VAS) and AROM of the shoulder were assessed at baseline and after the 8-week treatment. The primary analysis was the group × time interaction. RESULTS: Two-by-two mixed analysis of variance (ANOVA) revealed a significant group × time interaction for VAS (F = 29.67; p < 0.01); AROM in flexion (F = 12.05; p < 0.01), internal rotation (F = 6.62; p < 0.05) and external rotation (F = 16.93; p < 0.01) in favor of the experimental group. The two-by-two mixed ANOVA revealed a significant main effect of time for VAS (F = 1648.47; p < 0.01); AROM in flexion (F = 591.70; p < 0.01), extension (F = 114.57; p < 0.01), abduction (F = 1602.04; p < 0.01), internal rotation (F = 664.14; p < 0.01) and external rotation (F = 1096.92; p < 0.01). No other significant differences were found. CONCLUSIONS: NME is superior to strengthening exercises in terms of pain and AROM of shoulder flexion, internal rotation and external rotation in individuals with idiopathic FS. NME could be used to treat individuals with FS. TRIAL REGISTRATION: Trial registration number: ChiCTR2100054453. Registration date: 17/12/2021.
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Bursite , Terapia por Exercício , Humanos , Ombro , Dor , Amplitude de Movimento Articular , Bursite/terapia , Dor de Ombro/diagnóstico , Dor de Ombro/terapia , Resultado do TratamentoRESUMO
The Orai channel is characterized by voltage independence, low conductance, and high Ca2+ selectivity and plays an important role in Ca2+ influx through the plasma membrane (PM). How the channel is activated and promotes Ca2+ permeation is not well understood. Here, we report the crystal structure and cryo-electron microscopy (cryo-EM) reconstruction of a Drosophila melanogaster Orai (dOrai) mutant (P288L) channel that is constitutively active according to electrophysiology. The open state of the Orai channel showed a hexameric assembly in which 6 transmembrane 1 (TM1) helices in the center form the ion-conducting pore, and 6 TM4 helices in the periphery form extended long helices. Orai channel activation requires conformational transduction from TM4 to TM1 and eventually causes the basic section of TM1 to twist outward. The wider pore on the cytosolic side aggregates anions to increase the potential gradient across the membrane and thus facilitate Ca2+ permeation. The open-state structure of the Orai channel offers insights into channel assembly, channel activation, and Ca2+ permeation.
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Canais de Cálcio/metabolismo , Cálcio/metabolismo , Proteínas de Drosophila/metabolismo , Proteína ORAI1/metabolismo , Animais , Cálcio/fisiologia , Membrana Celular/metabolismo , Microscopia Crioeletrônica , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Ativação do Canal Iônico/fisiologia , Proteínas de Membrana/metabolismo , Proteína ORAI1/genética , Estrutura Secundária de ProteínaRESUMO
The cotton bollworm, Helicoverpa armigera is one of the worldwide pests. Electrophysiological properties of voltage-gated sodium channels in central neurons of sensitive and pyrethroid resistant H. armigera were investigated using whole-cell patch clamp technique. The modification effects of pyrethroid insecticides deltamethrin and tefluthrin on sodium channels were also compared. The V0.5 of voltage dependence of activation of resistant H. armigera sodium channels (resistant channels) exhibited an obvious depolarizing shift by 13.52 mV compared to that of sensitive H. armigera sodium channels (sensitive channels). In contrast, the V0.5 of the voltage dependence of steady-state inactivation of the resistant channels showed a significant hyperpolarizing shift by 7.59 mV in comparison with that of the sensitive channels. The time course of recovery from inactivation for the resistant channels was prolonged significantly, by 0.17 ms, compared with that for the sensitive channels. We also assessed the use-dependent effects of deltamethrin and tefluthrin on sensitive sodium channels. Repetitive depolarization remarkably increased the extent of the sensitive channel modification by 10 µM deltamethrin by ~4.61-fold but had no effect on the extent of sensitive channel modifications by 10 µM tefluthrin. These results provide more direct evidence for the presence of nerve insensitivity in resistant H. armigera strains in North of China. The sodium channels of the resistant H. armigera differ from those of the sensitive H. armigera in the fundamental electrophysiological properties, and correspondingly, have a different response to the modification of pyrethroids. Both deltamethrin and tefluthrin have effects on the closed state of the sensitive sodium channels, but deltamethrin has higher affinity to the open state of these channels.
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Inseticidas , Mariposas , Piretrinas , Animais , China , Ciclopropanos , Hidrocarbonetos Fluorados , Inseticidas/toxicidade , Neurônios , Nitrilas , Piretrinas/toxicidadeRESUMO
An amendment to this paper has been published and can be accessed via the original article.
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In the treatment of coronary artery disease (CAD), the use of stent implantation often leads to clinical complications such as restenosis, delayed endothelial healing, and thrombosis. Here, we develop a double drug sustained-release coating for the stent surface by grafting heparin/NONOate nanoparticles (Hep/NONOates). The Hep/NONOates and surface modification of the stent were characterized by X-ray photoelectron spectroscopy, attenuated total reflection Fourier-transform infrared spectroscopy, static water contact angle, and scanning electron microscopy (SEM), and the release behaviors of the anticoagulant, heparin (Hep) and the bioactive molecule, nitric oxide (NO) were studied. Furthermore, the blood compatibility and cytotoxicity of the modified stent were evaluated by whole blood adhesion and platelet adhesion tests, hemolysis assay, morphological changes of red blood cells, plasma recalcification time assay, in vitro coagulation time tests, and MTT assay. Finally, the results of a rabbit carotid artery stent implantation experiment showed that the double drug sustained-release coating for the stent can accelerate regeneration of endothelial cells and keep good anticoagulant activity. This study can provide new design ideas based on nanotechnology for improving the safety and effectiveness of drug-eluting stents.
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Anticoagulantes/uso terapêutico , Stents Farmacológicos , Heparina/uso terapêutico , Nanopartículas/química , Doadores de Óxido Nítrico/uso terapêutico , Compostos Nitrosos/uso terapêutico , Animais , Anticoagulantes/química , Anticoagulantes/toxicidade , Aterosclerose/terapia , Artérias Carótidas/cirurgia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Materiais Revestidos Biocompatíveis/toxicidade , Heparina/química , Heparina/toxicidade , Nanopartículas/toxicidade , Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/toxicidade , Compostos Nitrosos/química , Compostos Nitrosos/toxicidade , CoelhosRESUMO
The gastrointestinal (GI) tract is inhabited by a diverse array of microbes, which play crucial roles in health and disease. Dysbiosis of microbiota has been tightly linked to gastrointestinal inflammatory and malignant diseases. Here we highlight the role of Helicobacter pylori alongside gastric microbiota associated with gastric inflammation and cancer. We summarize the taxonomic and functional aspects of intestinal microbiota linked to inflammatory bowel diseases (IBD), irritable bowel syndrome (IBS), and colorectal cancer in clinical investigations. We also discuss microbiome-related animal models. Nevertheless, there are tremendous opportunities to reveal the causality of microbiota in health and disease and detailed microbe-host interaction mechanisms by which how dysbiosis is causally linked to inflammatory disease and cancer, in turn, potentializing clinical interventions with a personalized high efficacy.
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Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/patologia , Disbiose/microbiologia , Disbiose/patologia , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/patologia , Animais , Helicobacter pylori/patogenicidade , Humanos , Síndrome do Intestino Irritável/microbiologia , Síndrome do Intestino Irritável/patologiaRESUMO
Over the last few decades, intestinal microbial communities have been considered to play a vital role in host liver health. Acute liver injury (ALI) is the manifestation of sudden hepatic injury and arises from a variety of causes. The studies of dysbiosis in gut microbiota provide new insight into the pathogenesis of ALI. However, the relationship of gut microbiota and ALI is not well understood, and the contribution of gut microbiota to ALI has not been well characterized. In this chapter, we integrate several major pathogenic factors in ALI with the role of gut microbiota to stress the significance of gut microbiota in prevention and treatment of ALI.
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Disbiose , Microbioma Gastrointestinal , Hepatopatias/prevenção & controle , Hepatopatias/terapia , Fígado/lesões , Fígado/patologia , Doença Aguda/terapia , HumanosRESUMO
Transient receptor potential mucolipin subfamily 1 (TRPML1) is a nonselective cation channel mainly located in late endosomes and lysosomes. Mutations of the gene encoding human TRPML1 can cause severe lysosomal diseases. The activity of TRPML1 is regulated by both Ca2+ and H+, which are important for its critical physiological functions in membrane trafficking, exocytosis, autophagy, and intracellular signal transduction. However, the molecular mechanism of its dual regulation by Ca2+ and H+ remains elusive. Here, using a mutant screening method in combination with a whole-cell patch clamp technique, we identified a key TRPML1 residue, Asp-472, responsible for both fast calcium-dependent inactivation (FCDI) and slow calcium-dependent inactivation (SCDI) as well as H+ regulation. We also found that, in acidic pH, H+ can significantly delay FCDI and abolish SCDI and thereby presumably facilitate the ion conductance of the human TRPML1 channel. In summary, we have identified a key residue critical for Ca2+-induced inhibition of TRPML1 channel currents and uncovered pH-dependent regulation of this channel, providing vital information regarding the detailed mechanism of action of human TRPML1.
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Ácido Aspártico/metabolismo , Cálcio/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Ácido Aspártico/análise , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Modelos Moleculares , Técnicas de Patch-Clamp , Canais de Potencial de Receptor Transitório/químicaRESUMO
The medial prefrontal cortex (mPFC) is closely involved in many higher-order cognitive functions, including learning to associate temporally discontiguous events (called temporal associative learning). However, direct evidence for the role of mPFC and the neural pathway underlying modulation of temporal associative motor learning is sparse. Here, we show that optogenetic inhibition of the mPFC or its axon terminals at the pontine nuclei (PN) during trace intervals or whole trial period significantly impaired the trace eyeblink conditioning (TEC), but had no significant effects on TEC during the conditioned stimulus or intertrial interval period. Our results suggest that activities associated with the mPFC-PN projection during trace intervals is crucial for trace associative motor learning. This finding is of great importance in understanding the mechanisms and the relevant neural pathways underlying mPFC modulation of temporal associative motor learning.
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Condicionamento Palpebral/fisiologia , Ponte/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Axônios/fisiologia , Masculino , Vias Neurais/fisiologia , Optogenética , Ratos Sprague-Dawley , Fatores de TempoRESUMO
Diverse and powerful mechanisms have evolved to enable organisms to modulate learning and memory under a variety of survival conditions. Cumulative evidence has shown that the prefrontal cortex (PFC) is closely involved in many higher-order cognitive functions. However, when and how the medial PFC (mPFC) modulates associative motor learning remains largely unknown. Here, we show that delay eyeblink conditioning (DEC) with the weak conditioned stimulus (wCS) but not the strong CS (sCS) elicited a significant increase in the levels of c-Fos expression in caudal mPFC. Both optogenetic inhibition and activation of the bilateral caudal mPFC, or its axon terminals at the pontine nucleus (PN) contralateral to the training eye, significantly impaired the acquisition, recent and remote retrieval of DEC with the wCS but not the sCS. However, direct optogenetic activation of the contralateral PN had no significant effect on the acquisition, recent and remote retrieval of DEC. These results are of great importance in understanding the elusive role of the mPFC and its projection to PN in subserving the associative motor learning under suboptimal learning cue.
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Aprendizagem por Associação/fisiologia , Sinais (Psicologia) , Atividade Motora/fisiologia , Vias Neurais/fisiologia , Tegmento Pontino/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Proteínas de Ligação ao Cálcio , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Condicionamento Clássico , Potenciais Pós-Sinápticos Excitadores/genética , Agonistas de Receptores de GABA-A/farmacologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Muscimol/farmacologia , Optogenética , Farmacogenética , Ratos , Ratos Sprague-Dawley , Transdução GenéticaRESUMO
Prepulse inhibition (PPI) and habituation of the acoustic startle response (ASR) are considered to be effective neurobiological measures of sensorimotor gating and information processing. The deficit of PPI and habituation of ASR has been proposed to be candidate endophenotypes of schizophrenia spectrum disorders. However, there has been little information on PPI and ASR measures in Chinese. The present study aimed to provide more information about the characteristics of PPI and ASR in young healthy Chinese and investigate their sensitivity to experimental parameters and characteristics of population. In this study, we examined the PPI and habituation of ASR in 41 young healthy adults (21 males and 20 females), using an acoustic startle stimulus of 115 dB and a prepulse of 75 dB at a lead interval (LI) of 60 ms and 120 ms, respectively. The behavioral performance demonstrated that the PPI and habituation of ASR in all the young participants were robust. The significant difference was not observed in PPI and habituation between male and female. The block effect on PPI was significant; PPI reduces with increasing training. Latency facilitation was observed under prepulse conditions, with a significant effect of LI. Compared to previous studies in Caucasians, Chinese in this study shows a higher habituation and PPI. In conclusion, this research provides more data of behavioral characteristics of PPI and ASR in young healthy Chinese. Chinese in this study shows a higher habituation and PPI than Caucasians in previous studies.
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Inibição Pré-Pulso , Esquizofrenia , Estimulação Acústica , Povo Asiático , Feminino , Humanos , Masculino , Reflexo de SobressaltoRESUMO
Mitochondrial calcium uniporter (MCU) is the pore-forming subunit of the entire uniporter complex and plays an important role in mitochondrial calcium uptake. However, the single channel recording of MCU remains controversial. Here, we expressed and purified different MCU proteins and then reconstituted them into planar lipid bilayers for single channel recording. We showed that MCU alone from Pyronema omphalodes (pMCU) is active with prominent single channel Ca2+ currents. In sharp contrast, MCU alone from Homo sapiens (hMCU) is inactive. The essential MCU regulator (EMRE) activates hMCU, and therefore, the complex (hMCU-hEMRE) shows prominent single channel Ca2+ currents. These single channel currents are sensitive to the specific MCU inhibitor Ruthenium Red. Our results clearly demonstrate that active MCU can conduct large amounts of calcium into the mitochondria.
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Canais de Cálcio/química , Sinalização do Cálcio , Cálcio/química , Ativação do Canal Iônico , Bicamadas Lipídicas/química , Potencial da Membrana Mitocondrial , Membranas Mitocondriais/química , Humanos , Especificidade da EspécieRESUMO
The gut microbiota exhibit diurnal compositional and functional oscillations that influence the host homeostasis. However, the upstream factors that affect the microbial oscillations remain elusive. Here, we focused on the potential impact of light exposure, the main factor that affects the host circadian oscillation, on the diurnal oscillations of intestinal microflora to explore the upstream factor that governs the fluctuations of the gut microbes. The gut microbiota of the mice that were underwent regular light/dark (LD) cycles exhibited a robust rhythm at both compositional and functional level, in all parts of the intestine. Comparably, constant darkness (Dark-Dark, DD) led to the loss of the rhythmic oscillations in almost all parts of the intestine. Additionally, the abundance of Clostridia in DD conditions was dramatically enhanced in the small intestine. Our data indicated light exposure is the upstream factor that governs the regular diurnal fluctuations of gut microbiota in vivo.
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Ritmo Circadiano/fisiologia , Ritmo Circadiano/efeitos da radiação , Microbioma Gastrointestinal/fisiologia , Microbioma Gastrointestinal/efeitos da radiação , Luz , Fotoperíodo , Animais , Ceco/microbiologia , Ceco/efeitos da radiação , Clostridium/isolamento & purificação , Escuridão , Microbioma Gastrointestinal/genética , Mucosa Intestinal/microbiologia , Mucosa Intestinal/efeitos da radiação , Intestino Delgado/microbiologia , Intestino Delgado/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos BALB CRESUMO
BACKGROUND: L-Fucose (Fuc), a six-deoxy hexose monosaccharide, is present endogenously in humans and animals and has a wide range of biological functions. In the present study, we aimed to examine the effect of Fuc on obesity and hepatic steatosis in mice fed a high-fat diet (HFD). METHODS: C57BL/6 mice were fed a normal chow (NC) or HFD for 18 weeks to induce obesity and fatty liver. Fuc was administered intragastrically from the 8th week to the end of the experiment (18 weeks). RESULTS: Metagenomic analysis showed that HFD altered the genomic profile of gut microbiota in the mice; specifically, expression of alpha-L-fucosidase, the gene responsible for Fuc generation, was markedly reduced in the HFD group compared with that in the NC group. Fuc treatment decreased body weight gain, fat accumulation, and hepatic triglyceride elevation in HFD-fed mice. In addition, Fuc decreased the levels of endotoxin-producing bacteria of the Desulfovibrionaceae family and restored HFD-induced enteric dysbiosis at both compositional and functional levels. CONCLUSION: Our findings suggest that Fuc might be a novel strategy to treat HFD-induced obesity and fatty liver.