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Journal of Nanobiotechnology Jul 2024Reperfusion therapy is critical for saving heart muscle after myocardial infarction, but the process of restoring blood flow can itself exacerbate injury to the...
Targeting delivery of miR-146a via IMTP modified milk exosomes exerted cardioprotective effects by inhibiting NF-κB signaling pathway after myocardial ischemia-reperfusion injury.
Reperfusion therapy is critical for saving heart muscle after myocardial infarction, but the process of restoring blood flow can itself exacerbate injury to the myocardium. This phenomenon is known as myocardial ischemia-reperfusion injury (MIRI), which includes oxidative stress, inflammation, and further cell death. microRNA-146a (miR-146a) is known to play a significant role in regulating the immune response and inflammation, and has been studied for its potential impact on the improvement of heart function after myocardial injury. However, the delivery of miR-146a to the heart in a specific and efficient manner remains a challenge as extracellular RNAs are unstable and rapidly degraded. Milk exosomes (MEs) have been proposed as ideal delivery platform for miRNA-based therapy as they can protect miRNAs from RNase degradation. In this study, the effects of miR-146a containing MEs (MEs-miR-146a) on improvement of cardiac function were examined in a rat model of MIRI. To enhance the targeting delivery of MEs-miR-146a to the site of myocardial injury, the ischemic myocardium-targeted peptide IMTP was modified onto the surfaces, and whether the modified MEs-miR-146a could exert a better therapeutic role was examined by echocardiography, myocardial injury indicators and the levels of inflammatory factors. Furthermore, the expressions of miR-146a mediated NF-κB signaling pathway-related proteins were detected by western blotting and qRT-PCR to further elucidate its mechanisms. MiR-146 mimics were successfully loaded into the MEs by electroporation at a square wave 1000 V voltage and 0.1 ms pulse duration. MEs-miR-146a can be up-taken by cardiomyocytes and protected the cells from oxygen glucose deprivation/reperfusion induced damage in vitro. Oral administration of MEs-miR-146a decreased myocardial tissue apoptosis and the expression of inflammatory factors and improved cardiac function after MIRI. The miR-146a level in myocardium tissues was significantly increased after the administration IMTP modified MEs-miR-146a, which was higher than that of the MEs-miR-146a group. In addition, intravenous injection of IMTP modified MEs-miR-146a enhanced the targeting to heart, improved cardiac function, reduced myocardial tissue apoptosis and suppressed inflammation after MIRI, which was more effective than the MEs-miR-146a treatment. Moreover, IMTP modified MEs-miR-146a reduced the protein levels of IRAK1, TRAF6 and p-p65. Therefore, IMTP modified MEs-miR-146a exerted their anti-inflammatory effect by inhibiting the IRAK1/TRAF6/NF-κB signaling pathway. Taken together, our findings suggested miR-146a containing MEs may be a promising strategy for the treatment of MIRI with better outcome after modification with ischemic myocardium-targeted peptide, which was expected to be applied in clinical practice in future.
Topics: Animals; MicroRNAs; Myocardial Reperfusion Injury; Exosomes; NF-kappa B; Signal Transduction; Rats; Rats, Sprague-Dawley; Male; Milk; Myocardium; Cardiotonic Agents; Myocytes, Cardiac
PubMed: 38951872
DOI: 10.1186/s12951-024-02631-0 -
Journal of Nanobiotechnology Jul 2024Numerous studies have confirmed the involvement of extracellular vesicles (EVs) in various physiological processes, including cellular death and tissue damage. Recently,...
BACKGROUND
Numerous studies have confirmed the involvement of extracellular vesicles (EVs) in various physiological processes, including cellular death and tissue damage. Recently, we reported that EVs derived from ischemia-reperfusion heart exacerbate cardiac injury. However, the role of EVs from healthy heart tissue (heart-derived EVs, or cEVs) on myocardial ischemia-reperfusion (MI/R) injury remains unclear.
RESULTS
Here, we demonstrated that intramyocardial administration of cEVs significantly enhanced cardiac function and reduced cardiac damage in murine MI/R injury models. cEVs treatment effectively inhibited ferroptosis and maintained mitochondrial homeostasis in cardiomyocytes subjected to ischemia-reperfusion injury. Further results revealed that cEVs can transfer ATP5a1 into cardiomyocytes, thereby suppressing mitochondrial ROS production, alleviating mitochondrial damage, and inhibiting cardiomyocyte ferroptosis. Knockdown of ATP5a1 abolished the protective effects of cEVs. Furthermore, we found that the majority of cEVs are derived from cardiomyocytes, and ATP5a1 in cEVs primarily originates from cardiomyocytes of the healthy murine heart. Moreover, we demonstrated that adipose-derived stem cells (ADSC)-derived EVs with ATP5a1 overexpression showed much better efficacy on the therapy of MI/R injury compared to control ADSC-derived EVs.
CONCLUSIONS
These findings emphasized the protective role of cEVs in cardiac injury and highlighted the therapeutic potential of targeting ATP5a1 as an important approach for managing myocardial damage induced by MI/R injury.
Topics: Animals; Extracellular Vesicles; Mice; Myocardial Reperfusion Injury; Myocytes, Cardiac; Male; Mice, Inbred C57BL; Mitochondrial Proton-Translocating ATPases; Mitochondria; Myocardium; Reactive Oxygen Species; Ferroptosis; Disease Models, Animal
PubMed: 38951822
DOI: 10.1186/s12951-024-02618-x -
Molecular and Cellular Biochemistry Jun 2024Despite the implementation of novel therapeutic regimens and extensive research efforts, chemoresistance remains a formidable challenge in the treatment of acute myeloid...
Despite the implementation of novel therapeutic regimens and extensive research efforts, chemoresistance remains a formidable challenge in the treatment of acute myeloid leukemia (AML). Notably, the involvement of lysosomes in chemoresistance has sparked interest in developing lysosome-targeted therapies to sensitize tumor cells to currently approved chemotherapy or as innovative pharmacological approaches. Moreover, as ion channels on the lysosomal membrane are critical regulators of lysosomal function, they present potential as novel targets for enhancing chemosensitivity. Here, we discovered that the expression of a lysosomal cation channel, namely transient receptor potential mucolipin 1 (TRPML1), was elevated in AML cells. Inhibiting TRPML1 individually does not impact the proliferation and apoptosis of AML cells. Importantly, inhibition of TRPML1 demonstrated the potential to modulate the sensitivity of AML cells to chemotherapeutic agents. Exploration of the underlying mechanisms revealed that suppression of TRPML1 impaired autophagy while concurrently increasing the production of reactive oxygen species (ROS) and ROS-mediated lipid peroxidation (Lipid-ROS) in AML cells. Finally, the knockdown of TRPML1 significantly reduced OCI-AML3 tumor growth following chemotherapy in a mouse model of human leukemia. In summary, targeting TRPML1 represents a promising approach for combination therapy aimed at enhancing chemosensitivity in treating AML.
PubMed: 38951379
DOI: 10.1007/s11010-024-05054-5 -
Nature Communications Jun 2024Keratoconus, a disorder characterized by corneal thinning and weakening, results in vision loss. Corneal crosslinking (CXL) can halt the progression of keratoconus. The...
Keratoconus, a disorder characterized by corneal thinning and weakening, results in vision loss. Corneal crosslinking (CXL) can halt the progression of keratoconus. The development of accelerated corneal crosslinking (A-CXL) protocols to shorten the treatment time has been hampered by the rapid depletion of stromal oxygen when higher UVA intensities are used, resulting in a reduced cross-linking effect. It is therefore imperative to develop better methods to increase the oxygen concentration within the corneal stroma during the A-CXL process. Photocatalytic oxygen-generating nanomaterials are promising candidates to solve the hypoxia problem during A-CXL. Biocompatible graphitic carbon nitride (g-CN) quantum dots (QDs)-based oxygen self-sufficient platforms including g-CN QDs and riboflavin/g-CN QDs composites (RF@g-CN QDs) have been developed in this study. Both display excellent photocatalytic oxygen generation ability, high reactive oxygen species (ROS) yield, and excellent biosafety. More importantly, the A-CXL effect of the g-CN QDs or RF@g-CN QDs composite on male New Zealand white rabbits is better than that of the riboflavin 5'-phosphate sodium (RF) A-CXL protocol under the same conditions, indicating excellent strengthening of the cornea after A-CXL treatments. These lead us to suggest the potential application of g-CN QDs in A-CXL for corneal ectasias and other corneal diseases.
Topics: Quantum Dots; Animals; Graphite; Oxygen; Riboflavin; Rabbits; Male; Cross-Linking Reagents; Nitrogen Compounds; Reactive Oxygen Species; Keratoconus; Ultraviolet Rays; Cornea; Humans; Photosensitizing Agents; Corneal Stroma
PubMed: 38951161
DOI: 10.1038/s41467-024-49645-8 -
Accuracy of the defining characteristics of respiratory nursing diagnoses in patients with COVID-19.International Journal of Nursing... Jul 2024To analyze the accuracy of the defining characteristics of four respiratory nursing diagnoses (ND) in patients with COVID-19 and on oxygen therapy.
OBJECTIVE
To analyze the accuracy of the defining characteristics of four respiratory nursing diagnoses (ND) in patients with COVID-19 and on oxygen therapy.
METHODS
This is a cross-sectional study conducted in four Brazilian public hospitals in two regions of the country. A total of 474 patients with COVID-19 receiving oxygen therapy were assessed. Latent-adjusted class analysis with random effects was used to establish the sensitivity (Se) and specificity (Sp) of the defining characteristics evaluated for each ND.
RESULTS
Among the ND that constituted the study (impaired spontaneous ventilatory, impaired gas exchange, ineffective airway clearance, and dysfunctional ventilatory weaning response), the following defining characteristics had the highest simultaneous Se and Sp (>0.8): decrease in tidal volume, confusion, irritability, dyspnea, decreased breath sounds, orthopnea, impaired ability to cooperate and respond to coaching, and decrease in the level of consciousness.
CONCLUSIONS
Recognizing the clinical signs that predict respiratory ND in patients affected by COVID-19 can contribute to the nurse's accurate diagnostic inference and designate the appropriate nursing interventions to achieve the desired results and avoid complications.
PubMed: 38951045
DOI: 10.1111/2047-3095.12481 -
BMJ Open Jul 2024Acute hypoxaemic respiratory failure (AHRF) is associated with high mortality in sub-Saharan Africa. This is at least in part due to critical care-related resource...
Respiratory support with standard low-flow oxygen therapy, high-flow oxygen therapy or continuous positive airway pressure in adults with acute hypoxaemic respiratory failure in a resource-limited setting: protocol for a randomised, open-label, clinical trial - the Acute Respiratory Intervention...
RATIONALE
Acute hypoxaemic respiratory failure (AHRF) is associated with high mortality in sub-Saharan Africa. This is at least in part due to critical care-related resource constraints including limited access to invasive mechanical ventilation and/or highly skilled acute care workers. Continuous positive airway pressure (CPAP) and high-flow oxygen by nasal cannula (HFNC) may prove useful to reduce intubation, and therefore, improve survival outcomes among critically ill patients, particularly in resource-limited settings, but data in such settings are lacking. The aim of this study is to determine whether CPAP or HFNC as compared with standard oxygen therapy, could reduce mortality among adults presenting with AHRF in a resource-limited setting.
METHODS
This is a prospective, multicentre, randomised, controlled, stepped wedge trial, in which patients presenting with AHRF in Uganda will be randomly assigned to standard oxygen therapy delivered through a face mask, HFNC oxygen or CPAP. The primary outcome is all-cause mortality at 28 days. Secondary outcomes include the number of patients with criteria for intubation at day 7, the number of patients intubated at day 28, ventilator-free days at day 28 and tolerance of each respiratory support.
ETHICS AND DISSEMINATION
The study has obtained ethical approval from the Research and Ethics Committee, School of Biomedical Sciences, College of Health Sciences, Makerere University as well as the Uganda National Council for Science and Technology. Patients will be included after informed consent. The results will be submitted for publication in peer-reviewed journals.
TRIAL REGISTRATION NUMBER
NCT04693403.
PROTOCOL VERSION
8 September 2023; version 5.
Topics: Humans; Continuous Positive Airway Pressure; Oxygen Inhalation Therapy; Respiratory Insufficiency; Prospective Studies; Uganda; Adult; Hypoxia; Randomized Controlled Trials as Topic; Multicenter Studies as Topic; Acute Disease; Resource-Limited Settings
PubMed: 38951007
DOI: 10.1136/bmjopen-2023-082223 -
Drug and Therapeutics Bulletin Jul 2024Chronic obstructive pulmonary disease (COPD) is a common but underdiagnosed lung condition that is frequently managed inappropriately. It impacts poorest communities... (Review)
Review
Chronic obstructive pulmonary disease (COPD) is a common but underdiagnosed lung condition that is frequently managed inappropriately. It impacts poorest communities most, where health inequalities are greatest. New acute symptoms of breathlessness, cough, sputum production and wheeze should prompt clinical suspicion of underlying COPD in someone who is a current or ex-smoker (or has exposure to other risk factors) and be followed by referral for quality-assured spirometry once recovered. Management of COPD exacerbations in primary care includes use of short-acting bronchodilators if mild, and antibiotics and a short course of oral prednisolone if moderate/severe. Hospital at home schemes are safe and effective and should be considered for some patients exacerbating in the community; these are increasingly supported by remote monitoring ('virtual wards'). New or worsening hypoxia is an indication for hospital admission and therefore oxygen saturation monitoring is an important part of exacerbation management; clinicians should be aware of patient safety alerts around use of pulse oximeters. Exacerbations drive poor health status and lung function decline and therefore asking about exacerbation frequency at planned reviews and taking action to reduce these is an important part of long-term COPD care. An exacerbation is an opportunity to ensure that fundamentals of good care are addressed. Patients should be supported to understand and act on exacerbations through a supported self-management plan; prompt treatment is beneficial but should be balanced by careful antibiotic and corticosteroid stewardship. COPD rescue packs on repeat prescription are not recommended.
Topics: Pulmonary Disease, Chronic Obstructive; Humans; Primary Health Care; Bronchodilator Agents; Anti-Bacterial Agents; Disease Progression
PubMed: 38950975
DOI: 10.1136/dtb.2023.000026 -
The Journal of Asthma : Official... Jul 2024Near-fatal asthma (NFA) is a severe condition that can lead to respiratory arrest or high carbon dioxide levels, often requiring mechanical ventilation. Biologics have...
INTRODUCTION
Near-fatal asthma (NFA) is a severe condition that can lead to respiratory arrest or high carbon dioxide levels, often requiring mechanical ventilation. Biologics have revolutionized the management of severe asthma, significantly improving symptom severity, reducing the number of exacerbations and hospitalizations, and decreasing the need for oral corticosteroids. However, their effectiveness in acute settings, particularly for ICU patients experiencing severe respiratory failure, is not well-studied. More research is needed to determine if biologics can improve recovery during severe asthma exacerbations.Case Study: We report a case of NFA in a patient with severe allergic eosinophilic asthma, who experienced global respiratory failure necessitating hospitalization, intubation, and veno-venous extracorporeal membrane oxygenation (VV-ECMO). Given the severity of the clinical condition, compassionate administration of Benralizumab, which targets the IL-5 receptor, was attempted.
RESULTS
Five days from anti-IL5 receptor treatment start, the patient was extubated and the ECMO stopped. After the stepdown to the respiratory intensive care unit (RICU), the patient was weaned from oxygen therapy and subsequently discharged from hospital.
CONCLUSION
Benralizumab demonstrated rapid effectiveness in improving respiratory failure leading to successful weaning from VV-ECMO and subsequent extubation.
PubMed: 38949856
DOI: 10.1080/02770903.2024.2375287 -
Methods in Molecular Biology (Clifton,... 2024Photodynamic therapy (PDT) is an established therapy used for the treatment of cutaneous skin cancers and other non-infective ailments. There has been recent interest in...
Photodynamic therapy (PDT) is an established therapy used for the treatment of cutaneous skin cancers and other non-infective ailments. There has been recent interest in the opportunity to use aPDT (antimicrobial PDT) to treat skin and soft tissue infections. PDT utilizes photosensitizers that infiltrate all cells and "sensitize" them to a given wavelength of light. The photosensitizer is simply highly absorbent to a given wavelength of light and when excited will produce, in the presence of oxygen, damaging oxygen radicals and singlet oxygen. Bacterial cells are comparatively poor at combatting oxidative stress when compared with human cells therefore a degree of selective toxicity can be achieved with aPDT.In this chapter, we outline methodologies for testing aPDT in vitro using standard lab equipment.
Topics: Photosensitizing Agents; Photochemotherapy; Humans; Singlet Oxygen; Anti-Infective Agents
PubMed: 38949700
DOI: 10.1007/978-1-0716-3981-8_6 -
Investigative Ophthalmology & Visual... Jul 2024Glucocorticoid-induced glaucoma (GIG) is a prevalent complication associated with glucocorticoids (GCs), resulting in irreversible blindness. GIG is characterized by the...
PURPOSE
Glucocorticoid-induced glaucoma (GIG) is a prevalent complication associated with glucocorticoids (GCs), resulting in irreversible blindness. GIG is characterized by the abnormal deposition of extracellular matrix (ECM) in the trabecular meshwork (TM), elevation of intraocular pressure (IOP), and loss of retinal ganglion cells (RGCs). The objective of this study is to investigate the effects of nicotinamide riboside (NR) on TM in GIG.
METHODS
Primary human TM cells (pHTMs) and C57BL/6J mice responsive to GCs were utilized to establish in vitro and in vivo GIG models, respectively. The study assessed the expression of ECM-related proteins in TM and the functions of pHTMs to reflect the effects of NR. Mitochondrial morphology and function were also examined in the GIG cell model. GIG progression was monitored through IOP, RGCs, and mitochondrial morphology. Intracellular nicotinamide adenine dinucleotide (NAD+) levels of pHTMs were enzymatically assayed.
RESULTS
NR significantly prevented the expression of ECM-related proteins and alleviated dysfunction in pHTMs after dexamethasone treatment. Importantly, NR protected damaged ATP synthesis, preventing overexpression of mitochondrial reactive oxygen species (ROS), and also protect against decreased mitochondrial membrane potential induced by GCs in vitro. In the GIG mouse model, NR partially prevented the elevation of IOP and the loss of RGCs. Furthermore, NR effectively suppressed the excessive expression of ECM-associated proteins and mitigated mitochondrial damage in vivo.
CONCLUSIONS
Based on the results, NR effectively enhances intracellular levels of NAD+, thereby mitigating abnormal ECM deposition and TM dysfunction in GIG by attenuating mitochondrial damage induced by GCs. Thus, NR has promising potential as a therapeutic candidate for GIG treatment.
Topics: Animals; Niacinamide; Pyridinium Compounds; Glucocorticoids; Mice, Inbred C57BL; Mitochondria; Mice; Glaucoma; Extracellular Matrix; Intraocular Pressure; Humans; Disease Models, Animal; Trabecular Meshwork; Cells, Cultured; Retinal Ganglion Cells; Reactive Oxygen Species; Dexamethasone; Male
PubMed: 38949632
DOI: 10.1167/iovs.65.8.1