Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 74.931
Filter
1.
Sci Rep ; 14(1): 12716, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38830933

ABSTRACT

To explore the molecular pathogenesis of pulmonary arterial hypertension (PAH) and identify potential therapeutic targets, we performed transcriptome sequencing of lung tissue from mice with hypoxia-induced pulmonary hypertension. Our Gene Ontology analysis revealed that "extracellular matrix organization" ranked high in the biological process category, and matrix metallopeptidases (MMPs) and other proteases also played important roles in it. Moreover, compared with those in the normoxia group, we confirmed that MMPs expression was upregulated in the hypoxia group, while the hub gene Timp1 was downregulated. Crocin, a natural MMP inhibitor, was found to reduce inflammation, decrease MMPs levels, increase Timp1 expression levels, and attenuate hypoxia-induced pulmonary hypertension in mice. In addition, analysis of the cell distribution of MMPs and Timp1 in the human lung cell atlas using single-cell RNAseq datasets revealed that MMPs and Timp1 are mainly expressed in a population of fibroblasts. Moreover, in vitro experiments revealed that crocin significantly inhibited myofibroblast proliferation, migration, and extracellular matrix deposition. Furthermore, we demonstrated that crocin inhibited TGF-ß1-induced fibroblast activation and regulated the pulmonary arterial fibroblast MMP2/TIMP1 balance by inhibiting the TGF-ß1/Smad3 signaling pathway. In summary, our results indicate that crocin attenuates hypoxia-induced pulmonary hypertension in mice by inhibiting TGF-ß1-induced myofibroblast activation.


Subject(s)
Carotenoids , Hypertension, Pulmonary , Hypoxia , Matrix Metalloproteinase 2 , Tissue Inhibitor of Metalloproteinase-1 , Animals , Tissue Inhibitor of Metalloproteinase-1/metabolism , Tissue Inhibitor of Metalloproteinase-1/genetics , Mice , Hypoxia/metabolism , Hypoxia/complications , Hypertension, Pulmonary/etiology , Hypertension, Pulmonary/drug therapy , Hypertension, Pulmonary/metabolism , Carotenoids/pharmacology , Humans , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 2/genetics , Male , Signal Transduction/drug effects , Transforming Growth Factor beta1/metabolism , Disease Models, Animal , Cell Proliferation/drug effects , Mice, Inbred C57BL , Smad3 Protein/metabolism , Cell Movement/drug effects , Lung/pathology , Lung/metabolism , Lung/drug effects
2.
Alzheimers Res Ther ; 16(1): 121, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38831312

ABSTRACT

BACKGROUND: Beta-amyloid (Aß) deposition in the brain parenchyma is a crucial initiating step in the amyloid cascade hypothesis of Alzheimer's disease (AD) pathology. Furthermore, dysfunction of plaque-associated microglia, also known as disease-associated microglia (DAM) has been reported to accelerate Aß deposition and cognitive impairment. Our previous research demonstrated that intermittent hypoxia training (IHT) improved AD pathology by upregulating autophagy in DAM, thereby enhancing oligomeric Aß (oAß) clearance. Considering that oAß internalization is the initial stage of oAß clearance, this study focused on the IHT mechanism involved in upregulating Aß uptake by DAM. METHODS: IHT was administered to 8-month-old APP/PS1 mice or 6-month-old microglial vacuolar protein sorting 35 (VPS35) knockout mice in APP/PS1 background (MG VPS35 KO: APP/PS1) for 28 days. After the IHT, the spatial learning-memory capacity of the mice was assessed. Additionally, AD pathology was determined by estimating the nerve fiber and synapse density, Aß plaque deposition, and Aß load in the brain. A model of Aß-exposed microglia was constructed and treated with IHT to explore the related mechanism. Finally, triggering receptor expressed on myeloid cells 2 (TREM2) intracellular recycling and Aß internalization were measured using a fluorescence tracing technique. RESULTS: Our results showed that IHT ameliorated cognitive function and Aß pathology. In particular, IHT enhanced Aß endocytosis by augmenting the intracellular transport function of microglial TREM2, thereby contributing to Aß clearance. Furthermore, IHT specifically upregulated VPS35 in DAM, the primary cause for the enhanced intracellular recycling of TREM2. IHT lost ameliorative effect on Aß pathology in MG VPS35 KO: APP/PS1 mice brain. Lastly, the IHT mechanism of VPS35 upregulation in DAM was mediated by the transcriptional regulation of VPS35 by transcription factor EB (TFEB). CONCLUSION: IHT enhances Aß endocytosis in DAM by upregulating VPS35-dependent TREM2 recycling, thereby facilitating oAß clearance and mitigation of Aß pathology. Moreover, the transcriptional regulation of VPS35 by TFEB demonstrates a close link between endocytosis and autophagy in microglia. Our study further elucidates the IHT mechanism in improving AD pathology and provides evidence supporting the potential application of IHT as a complementary therapy for AD.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Endocytosis , Membrane Glycoproteins , Microglia , Plaque, Amyloid , Receptors, Immunologic , Animals , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Alzheimer Disease/genetics , Microglia/metabolism , Mice , Receptors, Immunologic/metabolism , Receptors, Immunologic/genetics , Membrane Glycoproteins/metabolism , Membrane Glycoproteins/genetics , Plaque, Amyloid/metabolism , Plaque, Amyloid/pathology , Amyloid beta-Peptides/metabolism , Endocytosis/physiology , Vesicular Transport Proteins/metabolism , Vesicular Transport Proteins/genetics , Mice, Transgenic , Hypoxia/metabolism , Mice, Knockout , Disease Models, Animal , Male , Brain/metabolism , Brain/pathology , Mice, Inbred C57BL
3.
Front Immunol ; 15: 1372959, 2024.
Article in English | MEDLINE | ID: mdl-38690277

ABSTRACT

Introduction: Hypoxia is a common pathological driver contributing to various forms of pulmonary vascular diseases leading to pulmonary hypertension (PH). Pulmonary interstitial macrophages (IMs) play pivotal roles in immune and vascular dysfunction, leading to inflammation, abnormal remodeling, and fibrosis in PH. However, IMs' response to hypoxia and their role in PH progression remain largely unknown. We utilized a murine model of hypoxia-induced PH to investigate the repertoire and functional profiles of IMs in response to acute and prolonged hypoxia, aiming to elucidate their contributions to PH development. Methods: We conducted single-cell transcriptomic analyses to characterize the repertoire and functional profiles of murine pulmonary IMs following exposure to hypobaric hypoxia for varying durations (0, 1, 3, 7, and 21 days). Hallmark pathways from the mouse Molecular Signatures Database were utilized to characterize the molecular function of the IM subpopulation in response to hypoxia. Results: Our analysis revealed an early acute inflammatory phase during acute hypoxia exposure (Days 1-3), which was resolved by Day 7, followed by a pro-remodeling phase during prolonged hypoxia (Days 7-21). These phases were marked by distinct subpopulations of IMs: MHCIIhiCCR2+EAR2+ cells characterized the acute inflammatory phase, while TLF+VCAM1hi cells dominated the pro-remodeling phase. The acute inflammatory phase exhibited enrichment in interferon-gamma, IL-2, and IL-6 pathways, while the pro-remodeling phase showed dysregulated chemokine production, hemoglobin clearance, and tissue repair profiles, along with activation of distinct complement pathways. Discussion: Our findings demonstrate the existence of distinct populations of pulmonary interstitial macrophages corresponding to acute and prolonged hypoxia exposure, pivotal in regulating the inflammatory and remodeling phases of PH pathogenesis. This understanding offers potential avenues for targeted interventions, tailored to specific populations and distinct phases of the disease. Moreover, further identification of triggers for pro-remodeling IMs holds promise in unveiling novel therapeutic strategies for pulmonary hypertension.


Subject(s)
Gene Expression Profiling , Hypertension, Pulmonary , Hypoxia , Single-Cell Analysis , Transcriptome , Animals , Mice , Hypoxia/metabolism , Hypoxia/immunology , Hypertension, Pulmonary/etiology , Hypertension, Pulmonary/immunology , Hypertension, Pulmonary/genetics , Macrophages, Alveolar/immunology , Macrophages, Alveolar/metabolism , Mice, Inbred C57BL , Disease Models, Animal , Male , Lung/immunology , Lung/pathology , Lung/metabolism
4.
Sleep Med Clin ; 19(2): 327-337, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38692756

ABSTRACT

In a variety of physiologic and pathologic states, people may experience both chronic sustained hypoxemia and intermittent hypoxemia ("combined" or "overlap" hypoxemia). In general, hypoxemia in such instances predicts a variety of maladaptive outcomes, including excess cardiovascular disease or mortality. However, hypoxemia may be one of the myriad phenotypic effects in such states, making it difficult to ascertain whether adverse outcomes are primarily driven by hypoxemia, and if so, whether these effects are due to intermittent versus sustained hypoxemia.


Subject(s)
Altitude , Hypoxia , Sleep Apnea Syndromes , Humans , Sleep Apnea Syndromes/complications , Sleep Apnea Syndromes/therapy , Chronic Disease , Lung Diseases/complications
5.
Nihon Yakurigaku Zasshi ; 159(3): 160-164, 2024.
Article in Japanese | MEDLINE | ID: mdl-38692880

ABSTRACT

The 2019 Nobel Prize in Physiology or Medicine was awarded to Dr. William G. Kaelin Jr, Dr. Peter J. Ratcliffe, and Dr. Gregg L. Semenza for their elucidation of new physiological mechanisms "How cells sense and adapt to oxygen availability". Moreover, two different drugs, HIF-PH inhibitors and HIF-2 inhibitors were also developed based on the discovery. Interestingly, those three doctors have different backgrounds as a medical oncologist, a nephrologist, and a pediatrician, respectively. They have started the research based on their own unique perspectives and eventually merged as "the elucidation of the response mechanism of living organisms to hypoxic environments". In this review, we will explain how the translational research that has begun to solve unmet clinical needs successfully contributed to the development of innovative therapeutic drugs.


Subject(s)
Hypoxia , Humans , Hypoxia/drug therapy , Hypoxia/metabolism , Animals , Drug Development , Molecular Targeted Therapy , Basic Helix-Loop-Helix Transcription Factors/metabolism
6.
Nihon Yakurigaku Zasshi ; 159(3): 165-168, 2024.
Article in Japanese | MEDLINE | ID: mdl-38692881

ABSTRACT

Molecular oxygen suffices the ATP production required for the survival of us aerobic organisms. But it is also true that oxygen acts as a source of reactive oxygen species that elicit a spectrum of damages in living organisms. To cope with such intrinsic ambiguity of biological activity oxygen exerts, aerobic mechanisms are equipped with an exquisite adaptive system, which sensitively detects partial pressure of oxygen within the body and controls appropriate oxygen supply to the tissues. Physiological responses to hypoxia are comprised of the acute and chronic phases, in the former of which the oxygen-sensing remains controversial particularly from mechanistic points of view. Recently, we have revealed that the prominently redox-sensitive cation channel TRPA1 plays key roles in oxygen-sensing mechanisms identified in the peripheral tissues and the central nervous system. In this review, we summarize recent development of researches on oxygen-sensing mechanisms including that in the carotid body, which has been recognized as the oxygen receptor organ central to acute oxygen-sensing. We also discuss how ubiquitously the TRPA1 contributes to the mechanisms underlying the acute phase of adaptation to hypoxia.


Subject(s)
Oxygen , TRPA1 Cation Channel , Transient Receptor Potential Channels , TRPA1 Cation Channel/metabolism , Humans , Oxygen/metabolism , Animals , Transient Receptor Potential Channels/metabolism , Hypoxia/metabolism , Calcium Channels/metabolism , Nerve Tissue Proteins/metabolism , Reactive Oxygen Species/metabolism , Carotid Body/metabolism
9.
Drug Dev Res ; 85(3): e22195, 2024 May.
Article in English | MEDLINE | ID: mdl-38704831

ABSTRACT

We investigated the angiogenesis-modulating ability of noscapine in vitro using osteosarcoma cell line (MG-63) and in vivo using a zebrafish model. MTT assay and the scratch wound healing assay were performed on the osteosarcoma cell line (MG-63) to analyze the cytotoxic effect and antimigrative ability of noscapine, respectively. We also observed the antiangiogenic ability of noscapine on zebrafish embryos by analyzing the blood vessels namely the dorsal aorta, and intersegmental vessels development at 24, 48, and 72 h postfertilization. Real-time polymerase chain reaction was used to analyze the hypoxia signaling molecules' gene expression in MG-63 cells and zebrafish embryos. The findings from the scratch wound healing demonstrated that noscapine stopped MG-63 cancer cells from migrating under both hypoxia and normoxia. Blood vessel development and the heart rate in zebrafish embryos were significantly reduced by noscapine under both hypoxia and normoxia which showed the hemodynamics impact of noscapine. Noscapine also downregulated the cobalt chloride (CoCl2) induced hypoxic signaling molecules' gene expression in MG-63 cells and zebrafish embryos. Therefore, noscapine may prevent MG-63 cancer cells from proliferating and migrating, as well as decrease the formation of new vessels and the production of growth factors linked to angiogenesis in vivo under both normoxic and hypoxic conditions.


Subject(s)
Hemodynamics , Neovascularization, Pathologic , Noscapine , Zebrafish , Animals , Humans , Noscapine/pharmacology , Cell Line, Tumor , Hemodynamics/drug effects , Neovascularization, Pathologic/drug therapy , Angiogenesis Inhibitors/pharmacology , Hypoxia , Cell Movement/drug effects , Embryo, Nonmammalian/drug effects , Osteosarcoma/drug therapy , Angiogenesis
10.
PLoS One ; 19(5): e0297137, 2024.
Article in English | MEDLINE | ID: mdl-38722851

ABSTRACT

BACKGROUND: Inhaled nitric oxide (iNO) has a beneficial effect on hypoxemic respiratory failure. The increased use of concurrent iNO and milrinone was observed. We aimed to report the trends of iNO use in the past 15 years in Taiwan and compare the first-year outcomes of combining iNO and milrinone to the iNO alone in very low birth weight preterm (VLBWP) infants under mechanical ventilation. METHODS: This nationwide cohort study enrolled preterm singleton infants with birth weight <1500g treated with iNO from 2004 to 2019. Infants were divided into two groups, with a combination of intravenous milrinone (Group 2, n = 166) and without milrinone (Group 1, n = 591). After propensity score matching (PSM), each group's sample size is 124. The primary outcomes were all-cause mortality and the respiratory condition, including ventilator use and duration. The secondary outcomes were preterm morbidities within one year after birth. RESULTS: After PSM, more infants in Group 2 needed inotropes. The mortality rate was significantly higher in Group 2 than in Group 1 from one month after birth till 1 year of age (55.1% vs. 13.5%) with the adjusted hazard ratio of 4.25 (95%CI = 2.42-7.47, p <0.001). For infants who died before 36 weeks of postmenstrual age (PMA), Group 2 had longer hospital stays compared to Group 1. For infants who survived after 36 weeks PMA, the incidence of moderate and severe bronchopulmonary dysplasia (BPD) was significantly higher in Group 2 than in Group 1. For infants who survived until one year of age, the incidence of pneumonia was significantly higher in Group 2 (28.30%) compared to Group 1 (12.62%) (p = 0.0153). CONCLUSION: Combined treatment of iNO and milrinone is increasingly applied in VLBWP infants in Taiwan. This retrospective study did not support the benefits of combining iNO and milrinone on one-year survival and BPD prevention. A future prospective study is warranted.


Subject(s)
Infant, Very Low Birth Weight , Milrinone , Nitric Oxide , Humans , Milrinone/administration & dosage , Milrinone/therapeutic use , Infant, Newborn , Nitric Oxide/administration & dosage , Nitric Oxide/therapeutic use , Male , Administration, Inhalation , Female , Retrospective Studies , Taiwan/epidemiology , Infant, Premature , Respiratory Insufficiency/drug therapy , Respiratory Insufficiency/mortality , Infant , Respiration, Artificial , Treatment Outcome , Hypoxia/drug therapy
11.
Cell Biol Toxicol ; 40(1): 32, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38767703

ABSTRACT

BACKGROUND: Recent studies have emphasized the critical role of Telocytes (TCs)-derived exosomes in organ tissue injury and repair. Our previous research showed a significant increase in ITGB1 within TCs. Pulmonary Arterial Hypertension (PAH) is marked by a loss of microvessel regeneration and progressive vascular remodeling. This study aims to investigate whether exosomes derived from ITGB1-modified TCs (ITGB1-Exo) could mitigate PAH. METHODS: We analyzed differentially expressed microRNAs (DEmiRs) in TCs using Affymetrix Genechip miRNA 4.0 arrays. Exosomes isolated from TC culture supernatants were verified through transmission electron microscopy and Nanoparticle Tracking Analysis. The impact of miR-429-3p-enriched exosomes (Exo-ITGB1) on hypoxia-induced pulmonary arterial smooth muscle cells (PASMCs) was evaluated using CCK-8, transwell assay, and inflammatory factor analysis. A four-week hypoxia-induced mouse model of PAH was constructed, and H&E staining, along with Immunofluorescence staining, were employed to assess PAH progression. RESULTS: Forty-five miRNAs exhibited significant differential expression in TCs following ITGB1 knockdown. Mus-miR-429-3p, significantly upregulated in ITGB1-overexpressing TCs and in ITGB1-modified TC-derived exosomes, was selected for further investigation. Exo-ITGB1 notably inhibited the migration, proliferation, and inflammation of PASMCs by targeting Rac1. Overexpressing Rac1 partly counteracted Exo-ITGB1's effects. In vivo administration of Exo-ITGB1 effectively reduced pulmonary vascular remodeling and inflammation. CONCLUSIONS: Our findings reveal that ITGB1-modified TC-derived exosomes exert anti-inflammatory effects and reverse vascular remodeling through the miR-429-3p/Rac1 axis. This provides potential therapeutic strategies for PAH treatment.


Subject(s)
Exosomes , Integrin beta1 , MicroRNAs , Telocytes , rac1 GTP-Binding Protein , MicroRNAs/genetics , MicroRNAs/metabolism , Animals , Exosomes/metabolism , Exosomes/genetics , rac1 GTP-Binding Protein/metabolism , rac1 GTP-Binding Protein/genetics , Integrin beta1/metabolism , Integrin beta1/genetics , Mice , Telocytes/metabolism , Male , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Mice, Inbred C57BL , Pulmonary Arterial Hypertension/metabolism , Pulmonary Arterial Hypertension/genetics , Pulmonary Arterial Hypertension/pathology , Hypoxia/metabolism , Hypoxia/genetics , Hypoxia/complications , Cell Proliferation/genetics , Cell Movement/genetics , Humans , Vascular Remodeling/genetics , Neuropeptides
12.
J Cardiothorac Surg ; 19(1): 273, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38702812

ABSTRACT

Acute type A aortic dissection is a life-threatening cardiovascular disease characterized by rapid onset and high mortality. Emergency surgery is the preferred and reliable treatment option. However, postoperative complications significantly impact patient prognosis. Hypoxemia, a common complication, poses challenges in clinical treatment, negatively affecting patient outcomes and increasing the risk of mortality. Therefore, it is crucial to study and comprehend the risk factors and treatment strategies for hypoxemia following acute type A aortic dissection to facilitate early intervention.


Subject(s)
Aortic Dissection , Hypoxia , Postoperative Complications , Humans , Aortic Dissection/surgery , Aortic Dissection/complications , Risk Factors , Hypoxia/etiology , Acute Disease , Aortic Aneurysm, Thoracic/surgery
13.
J Pak Med Assoc ; 74(4): 641-646, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38751254

ABSTRACT

Objectives: To determine if the integrated pulmonary index detects changes in ventilation status early in patients undergoing gastrointestinal endoscopy under sedation, and to determine the risk factors affecting hypoxia. METHODS: The retrospective study was conducted at the endoscopy unit of a tertiary university hospital in Turkey and comprised data between October 2018 and December 2019 related to patients of either gender aged >18 years who were assessed as American Society of Anaesthesiologists grade I-III and underwent elective lower and upper gastrointestinal endoscopy. Monitoring was done with capnography in addition to standard procedures. Data was analysed using SPSS 23. RESULTS: Of the 154 patients, 94(%) were females and 60(%) were males. The overall mean age was 50.88±11.8 years (range: 20-70 years). Mean time under anaesthesia was 23.58±4.91 minutes and mean endoscopy time was 21.73±5.06 minutes. During the procedure, hypoxia was observed in 42(27.3%) patients, severe hypoxia in 23(14.9%) and apnoea in 70(45.5%). Mean time between apnoea and hypoxia was 12.59±7.99 seconds, between apnoea and serious hypoxia 21.07±17.64 seconds, between integrated pulmonary index score 1 and hypoxia 12.91±8.17 sec, between integrated pulmonary index score 1 and serious hypoxia 21.59±14.13 seconds, between integrated pulmonary index score <7 and hypoxia 19.63±8.89 seconds, between integrated pulmonary index score <7 and serious hypoxia 28.39±12.66 seconds, between end-tidal carbon dioxide and hypoxia 12.95±8.33 seconds, and between end-tidal carbon dioxide and serious hypoxia 21.29±7.55 seconds. With integrated pulmonary index score 1, sensitivity value for predicting hypoxia and severe hypoxia was 88.1% and 95.7%, respectively, and specificity was 67% and 60.3%, respectively. With integrated pulmonary index score <7, the corresponding values were 100%, 100%, 42% and 64.1%, respectively. CONCLUSIONS: Capnographic monitoring, especially the follow-up integrated pulmonary index score, was found to be valuable and reliable in terms of finding both time and accuracy of the risk factor in the diagnosis of respiratory events.


Subject(s)
Capnography , Endoscopy, Gastrointestinal , Hypoxia , Humans , Female , Male , Middle Aged , Adult , Retrospective Studies , Hypoxia/diagnosis , Capnography/methods , Endoscopy, Gastrointestinal/methods , Aged , Apnea/diagnosis , Young Adult , Conscious Sedation/adverse effects , Conscious Sedation/methods , Turkey/epidemiology , Monitoring, Physiologic/methods
14.
FASEB J ; 38(10): e23671, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38752538

ABSTRACT

NLRP3 inflammasome activation has emerged as a critical initiator of inflammatory response in ischemic retinopathy. Here, we identified the effect of a potent, selective NLRP3 inhibitor, MCC950, on autophagy and apoptosis under hypoxia. Neonatal mice were exposed to hyperoxia for 5 days to establish oxygen-induced retinopathy (OIR) model. Intravitreal injection of MCC950 was given, and then autophagy and apoptosis markers were assessed. Retinal autophagy, apoptosis, and related pathways were evaluated by western blot, immunofluorescent labeling, transmission electron microscopy, and TUNEL assay. Autophagic activity in Müller glia after NLRP3 inflammasome inhibition, together with its influence on photoreceptor death, was studied using western blot, immunofluorescence staining, mRFP-GFP-LC3 adenovirus transfection, cell viability, proliferation, and apoptosis assays. Results showed that activation of NLRP3 inflammasome in Müller glia was detected in OIR model. MCC950 could improve impaired retinal autophagic flux and attenuate retinal apoptosis while it regulated the retinal AMPK/mTOR/ULK-1 pathway. Suppressed autophagy and depressed proliferation capacity resulting from hypoxia was promoted after MCC950 treatment in Müller glia. Inhibition of AMPK and ULK-1 pathway significantly interfered with the MCC950-induced autophagy activity, indicating MCC950 positively modulated autophagy through AMPK/mTOR/ULK-1 pathway in Müller cells. Furthermore, blockage of autophagy in Müller glia significantly induced apoptosis in the cocultured 661W photoreceptor cells, whereas MCC950 markedly preserved the density of photoreceptor cells. These findings substantiated the therapeutic potential of MCC950 against impaired autophagy and subsequent apoptosis under hypoxia. Such protective effect might involve the modulation of AMPK/mTOR/ULK-1 pathway. Targeting NLRP3 inflammasome in Müller glia could be beneficial for photoreceptor survival under hypoxic conditions.


Subject(s)
Apoptosis , Autophagy , Ependymoglial Cells , Furans , Indenes , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Sulfonamides , Animals , Autophagy/drug effects , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Mice , Apoptosis/drug effects , Sulfonamides/pharmacology , Inflammasomes/metabolism , Furans/pharmacology , Ependymoglial Cells/metabolism , Ependymoglial Cells/drug effects , Indenes/pharmacology , Mice, Inbred C57BL , Hypoxia/metabolism , Cyclic S-Oxides/pharmacology , Sulfones/pharmacology , Photoreceptor Cells, Vertebrate/metabolism , Photoreceptor Cells, Vertebrate/drug effects , Photoreceptor Cells, Vertebrate/pathology , Heterocyclic Compounds, 4 or More Rings/pharmacology , Photoreceptor Cells/metabolism , Photoreceptor Cells/drug effects , Signal Transduction/drug effects
15.
Cereb Cortex ; 34(5)2024 May 02.
Article in English | MEDLINE | ID: mdl-38752980

ABSTRACT

The effects of hypoxia on brain function remain largely unknown. This study aimed to clarify this issue by visual-stimulated functional magnetic resonance imaging design. Twenty-three college students with a 30-d high-altitude exposure were tested before, 1 week and 3 months after returning to sea level. Brain functional magnetic resonance imaging and retinal electroretinogram were acquired. One week after returning to sea level, decreased blood oxygenation level dependent in the right lingual gyrus accompanied with increased blood oxygenation level dependent in the frontal cortex and insular cortex, and decreased amplitude of electroretinogram a-wave in right eye; moreover, the bilateral lingual gyri showed increased functional connectivity within the dorsal visual stream pathway, and the blood oxygenation level dependent signals in the right lingual gyrus showed positive correlation with right retinal electroretinogram a-wave. Three months after returning to sea level, the blood oxygenation level dependent signals recovered to normal level, while intensively increased blood oxygenation level dependent signals in a broad of brain regions and decreased retinal electroretinogram were also existed. In conclusion, hypoxic exposure has long-term effects on visual cortex, and the impaired retinal electroretinogram may contribute to it. The increased functional connectivity of dorsal stream may compensate for the decreased function of retinal photoreceptor cells to maintain normal visual function.


Subject(s)
Electroretinography , Magnetic Resonance Imaging , Neuronal Plasticity , Visual Pathways , Humans , Male , Young Adult , Female , Neuronal Plasticity/physiology , Visual Pathways/physiology , Visual Pathways/diagnostic imaging , Hypoxia/physiopathology , Adult , Oxygen/blood , Visual Cortex/diagnostic imaging , Visual Cortex/physiology , Brain/physiology , Brain/diagnostic imaging , Photic Stimulation/methods , Retina/physiology , Retina/diagnostic imaging , Brain Mapping/methods
16.
J Glob Health ; 14: 04092, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38726546

ABSTRACT

Background: Medical oxygen is essential for managing hypoxaemia, which has a multifactorial origin, including acute and chronic lung diseases such as pneumonia, asthma, and severe malaria. The coronavirus disease 2019 (COVID-19) revealed substantial gaps in the availability and accessibility of safe medical oxygen, especially in low- and middle-income countries (LMICs). This study aimed to assess the availability and sources, as well as the barriers to the availability of functional medical oxygen in hospitals in Cameroon. Methods: This was a nationwide cross-sectional descriptive study conducted from 26 March to 1 June 2021. Using a convenient sampling technique, we sampled accredited public and private COVID-19 treatment centres in all ten regions in Cameroon. Representatives from the selected hospitals were provided with a pre-designed questionnaire assessing the availability, type, and state of medical oxygen in their facilities. All analyses were performed using R. Results: In total, 114 hospitals were included in this study, with functional medical oxygen available in 65% (74/114) of the hospitals. About 85% (23/27) of the reference hospitals and only 59% (51/87) of the district hospitals had available functional medical oxygen. Compared to district hospitals, reference hospitals were more likely to have central oxygen units (reference vs. district: 10 vs. 0%), oxygen cylinders (74 vs. 42%), and oxygen concentrators (79 vs. 51%). The most common barriers to the availability of medical oxygen were inadequate oxygen supply to meet needs (district vs. reference hospitals: 55 vs. 30%), long delays in oxygen bottle refills (51 vs. 49%), and long distances from oxygen suppliers (57 vs. 49%). Conclusions: The availability of medical oxygen in hospitals in Cameroon is suboptimal and more limited in districts compared to reference hospitals. The cost of medical oxygen, delays related to refills and supplies, and long distances from medical sources were the most common barriers to availability in Cameroon.


Subject(s)
COVID-19 , Health Services Accessibility , Hypoxia , Oxygen Inhalation Therapy , Humans , Cameroon , Cross-Sectional Studies , Hypoxia/therapy , Oxygen Inhalation Therapy/statistics & numerical data , COVID-19/therapy , COVID-19/epidemiology , Oxygen/supply & distribution , Surveys and Questionnaires
17.
Neuropharmacology ; 253: 109968, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38692453

ABSTRACT

Microglia are described as the immune cells of the brain, their immune properties have been extensively studied since first described, however, their neural functions have only been explored over the last decade. Microglia have an important role in maintaining homeostasis in the central nervous system by surveying their surroundings to detect pathogens or damage cells. While these are the classical functions described for microglia, more recently their neural functions have been defined; they are critical to the maturation of neurons during embryonic and postnatal development, phagocytic microglia remove excess synapses during development, a process called synaptic pruning, which is important to overall neural maturation. Furthermore, microglia can respond to neuronal activity and, together with astrocytes, can regulate neural activity, contributing to the equilibrium between excitation and inhibition through a feedback loop. Hypoxia at birth is a serious neurological condition that disrupts normal brain function resulting in seizures and epilepsy later in life. Evidence has shown that microglia may contribute to this hyperexcitability after neonatal hypoxia. This review will summarize the existing data on the role of microglia in the pathogenesis of neonatal hypoxia and the plausible mechanisms that contribute to the development of hyperexcitability after hypoxia in neonates. This article is part of the Special Issue on "Microglia".


Subject(s)
Epilepsy , Microglia , Microglia/physiology , Microglia/pathology , Humans , Animals , Epilepsy/physiopathology , Epilepsy/pathology , Infant, Newborn , Hypoxia/physiopathology , Brain/pathology , Brain/physiopathology
18.
Cancer J ; 30(3): 159-169, 2024.
Article in English | MEDLINE | ID: mdl-38753750

ABSTRACT

ABSTRACT: Imaging glucose metabolism with [18F]fluorodeoxyglucose positron emission tomography has transformed the diagnostic and treatment algorithms of numerous malignancies in clinical practice. The cancer phenotype, though, extends beyond dysregulation of this single pathway. Reprogramming of other pathways of metabolism, as well as altered perfusion and hypoxia, also typifies malignancy. These features provide other opportunities for imaging that have been developed and advanced into humans. In this review, we discuss imaging metabolism, perfusion, and hypoxia in cancer, focusing on the underlying biology to provide context. We conclude by highlighting the ability to image multiple facets of biology to better characterize cancer and guide targeted treatment.


Subject(s)
Fluorodeoxyglucose F18 , Neoplasms , Positron-Emission Tomography , Humans , Fluorodeoxyglucose F18/metabolism , Neoplasms/diagnostic imaging , Neoplasms/metabolism , Neoplasms/diagnosis , Positron-Emission Tomography/methods , Radiopharmaceuticals/metabolism , Hypoxia/metabolism , Hypoxia/diagnostic imaging
19.
Sci Adv ; 10(20): eadj3301, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38758780

ABSTRACT

Myeloid cells are highly prevalent in glioblastoma (GBM), existing in a spectrum of phenotypic and activation states. We now have limited knowledge of the tumor microenvironment (TME) determinants that influence the localization and the functions of the diverse myeloid cell populations in GBM. Here, we have utilized orthogonal imaging mass cytometry with single-cell and spatial transcriptomic approaches to identify and map the various myeloid populations in the human GBM tumor microenvironment (TME). Our results show that different myeloid populations have distinct and reproducible compartmentalization patterns in the GBM TME that is driven by tissue hypoxia, regional chemokine signaling, and varied homotypic and heterotypic cellular interactions. We subsequently identified specific tumor subregions in GBM, based on composition of identified myeloid cell populations, that were linked to patient survival. Our results provide insight into the spatial organization of myeloid cell subpopulations in GBM, and how this is predictive of clinical outcome.


Subject(s)
Glioblastoma , Myeloid Cells , Tumor Microenvironment , Glioblastoma/pathology , Glioblastoma/metabolism , Humans , Myeloid Cells/metabolism , Myeloid Cells/pathology , Brain Neoplasms/pathology , Brain Neoplasms/metabolism , Brain Neoplasms/genetics , Cell Line, Tumor , Single-Cell Analysis , Hypoxia/metabolism , Gene Expression Profiling
20.
ACS Nano ; 18(20): 13361-13376, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38728619

ABSTRACT

Oxygen therapy cannot rescue local lung hypoxia in patients with severe respiratory failure. Here, an inhalable platform is reported for overcoming the aberrant hypoxia-induced immune changes and alveolar damage using camouflaged poly(lactic-co-glycolic) acid (PLGA) microparticles with macrophage apoptotic body membrane (cMAB). cMABs are preloaded with mitochondria-targeting superoxide dismutase/catalase nanocomplexes (NCs) and modified with pathology-responsive macrophage growth factor colony-stimulating factor (CSF) chains, which form a core-shell platform called C-cMAB/NC with efficient deposition in deeper alveoli and high affinity to alveolar epithelial cells (AECs) after CSF chains are cleaved by matrix metalloproteinase 9. Therefore, NCs can be effectively transported into mitochondria to inhibit inflammasome-mediated AECs damage in mouse models of hypoxic acute lung injury. Additionally, the at-site CSF release is sufficient to rescue circulating monocytes and macrophages and alter their phenotypes, maximizing synergetic effects of NCs on creating a pro-regenerative microenvironment that enables resolution of lung injury and inflammation. This inhalable platform may have applications to numerous inflammatory lung diseases.


Subject(s)
Macrophages , Polylactic Acid-Polyglycolic Acid Copolymer , Animals , Mice , Macrophages/metabolism , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Mice, Inbred C57BL , Hypoxia , Acute Lung Injury/pathology , Lung Injury/pathology , Lung Injury/therapy , Administration, Inhalation , Apoptosis/drug effects
SELECTION OF CITATIONS
SEARCH DETAIL
...