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Cell Death & Disease Jun 2024S100a8/a9, largely released by polymorphonuclear neutrophils (PMNs), belongs to the S100 family of calcium-binding proteins and plays a role in a variety of inflammatory...
S100a8/a9, largely released by polymorphonuclear neutrophils (PMNs), belongs to the S100 family of calcium-binding proteins and plays a role in a variety of inflammatory diseases. Although S100a8/a9 has been reported to trigger endothelial cell apoptosis, the mechanisms of S100a8/a9-induced endothelial dysfunction during sepsis require in-depth research. We demonstrate that high expression levels of S100a8/a9 suppress Ndufa3 expression in mitochondrial complex I via downregulation of Nrf1 expression. Mitochondrial complex I deficiency contributes to NAD-dependent Sirt1 suppression, which induces mitochondrial disorders, including excessive fission and blocked mitophagy, and mtDNA released from damaged mitochondria ultimately activates ZBP1-mediated PANoptosis in endothelial cells. Moreover, based on comprehensive scRNA-seq and bulk RNA-seq analyses, S100A8/A9 neutrophils are closely associated with the circulating endothelial cell count (a useful marker of endothelial damage), and S100A8 is an independent risk factor for poor prognosis in sepsis patients.
Topics: Calgranulin A; Neutrophils; Sepsis; Humans; Calgranulin B; Mitochondria; Electron Transport Complex I; Endothelial Cells; Animals; Mice; Male; Human Umbilical Vein Endothelial Cells; Mitophagy; Mice, Inbred C57BL; Apoptosis
PubMed: 38942784
DOI: 10.1038/s41419-024-06849-6 -
Metabolic Engineering Jun 2024Vitamin B [D-pantothenic acid (D-PA)] is an essential water-soluble vitamin that is widely used in the food and feed industries. Currently, the relatively low...
Vitamin B [D-pantothenic acid (D-PA)] is an essential water-soluble vitamin that is widely used in the food and feed industries. Currently, the relatively low fermentation efficiency limits the industrial application of D-PA. Here, a plasmid-free D-PA hyperproducer was constructed using systematic metabolic engineering strategies. First, pyruvate was enriched by deleting the non-phosphotransferase system, inhibiting pyruvate competitive branches, and dynamically controlling the TCA cycle. Next, the (R)-pantoate pathway was enhanced by screening the rate-limiting enzyme PanBC and regulating the other enzymes of this pathway one by one. Then, to enhance NADPH sustainability, NADPH regeneration was achieved through the novel "PEACES" system by (1) expressing the NAD kinase gene ppnk from Clostridium glutamicum and the NADP-dependent gapC from Clostridium acetobutyricum and (2) knocking-out the endogenous sthA gene, which interacts with ilvC and panE in the D-PA biosynthesis pathway. Combined with transcriptome analysis, it was found that the membrane proteins OmpC and TolR promoted D-PA efflux by increasing membrane fluidity. Strain PA132 produced a D-PA titer of 83.26 g/L by two-stage fed-batch fermentation, which is the highest D-PA titer reported so far. This work established competitive producers for the industrial production of D-PA and provided an effective strategy for the production of related products.
PubMed: 38942195
DOI: 10.1016/j.ymben.2024.06.006 -
Journal of Colloid and Interface Science Jun 2024Membrane technology holds great potential for separation applications and also finds critical needs in biomedical fields, such as blood oxygenation. However, the...
Membrane technology holds great potential for separation applications and also finds critical needs in biomedical fields, such as blood oxygenation. However, the bottlenecks in gas permeation, plasma leakage, and especially hemocompatibility hamper the development of membrane oxygenation. It remains extremely challenging to design efficient membranes and elucidate underlying principles. In this study, we report biomimetic decoration of asymmetric nanoporous membranes by ultrathin Fe-tannic acid metal-ligand networks to realize fast gas exchange with on plasma leakage and substantially enhance hemocompatibility. Because the intrinsic nanopores facilitate gas permeability and the Fe-catechol layers enable superior hydrophilicity and electronegativity to original surfaces, the modified membranes exhibit high transport properties for gases and great resistances to protein adsorption, platelet activation, coagulation, thrombosis, and hemolysis. Molecular docking and density functional theory simulations indicate that more preferential adsorption of metal-ligand networks with water molecules than proteins is critical to anticoagulation. Moreover, benefiting from the better antiaging property gave by biomimetic decoration, the membranes after four-month aging present gas permeances similar to or even larger than those of pristine ones, despite the initial permeation decline. Importantly, for blood oxygenation, the designed membranes after aging show fast O and CO exchange processes with rates up to 28-17 and 97-47 mL m min, respectively, accompanied with no detectable thrombus and plasma leakage. We envisage that the biomimetic decoration of nanoporous membranes provide a feasible route to achieve great biocompatibility and transport capability for various applications.
PubMed: 38941931
DOI: 10.1016/j.jcis.2024.06.173 -
Neurology(R) Neuroimmunology &... Sep 2024To systematically describe the clinical picture of double-antibody seronegative neuromyelitis optica spectrum disorders (DN-NMOSD) with specific emphasis on retinal...
BACKGROUND AND OBJECTIVES
To systematically describe the clinical picture of double-antibody seronegative neuromyelitis optica spectrum disorders (DN-NMOSD) with specific emphasis on retinal involvement.
METHODS
Cross-sectional data of 25 people with DN-NMOSD (48 eyes) with and without a history of optic neuritis (ON) were included in this study along with data from 25 people with aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorder (AQP4-NMOSD, 46 eyes) and from 25 healthy controls (HCs, 49 eyes) for comparison. All groups were matched for age and sex and included from the collaborative retrospective study of retinal optical coherence tomography (OCT) in neuromyelitis optica (CROCTINO). Participants underwent OCT with central postprocessing and local neurologic examination and antibody testing. Retinal neurodegeneration was quantified as peripapillary retinal nerve fiber layer thickness (pRNFL) and combined ganglion cell and inner plexiform layer thickness (GCIPL).
RESULTS
This DN-NMOSD cohort had a history of [median (inter-quartile range)] 6 (5; 9) attacks within their 5 ± 4 years since onset. Myelitis and ON were the most common attack types. In DN-NMOSD eyes after ON, pRNFL ( < 0.001) and GCIPL ( = 0.023) were thinner compared with eyes of HCs. Even after only one ON episode, DN-NMOSD eyes already had considerable neuroaxonal loss compared with HCs. In DN-NMOSD eyes without a history of ON, pRNFL ( = 0.027) and GCIPL ( = 0.022) were also reduced compared with eyes of HCs. However, there was no difference in pRNFL and GCIPL between DN-NMOSD and AQP4-NMOSD for the whole group and for subsets with a history of ON and without a history of ON-as well as between variances of retinal layer thicknesses.
DISCUSSION
DN-NMOSD is characterized by severe retinal damage after ON and attack-independent retinal neurodegeneration. Most of the damage occurs during the first ON episode, which highlights the need for better diagnostic markers in DN-NMOSD to facilitate an earlier diagnosis as well as for effective and early treatments. In this study, people with DN-NMOSD presented with homogeneous clinical and imaging findings potentially suggesting a common retinal pathology in these patients.
Topics: Humans; Neuromyelitis Optica; Female; Male; Adult; Cross-Sectional Studies; Middle Aged; Tomography, Optical Coherence; Aquaporin 4; Retrospective Studies; Autoantibodies; Retina
PubMed: 38941573
DOI: 10.1212/NXI.0000000000200273 -
Proceedings of the National Academy of... Jul 2024TMEM16F is a calcium-activated phospholipid scramblase and nonselective ion channel, which allows the movement of lipids bidirectionally across the plasma membrane....
TMEM16F is a calcium-activated phospholipid scramblase and nonselective ion channel, which allows the movement of lipids bidirectionally across the plasma membrane. While the functions of TMEM16F have been extensively characterized in multiple cell types, the role of TMEM16F in the central nervous system remains largely unknown. Here, we sought to study how TMEM16F in the brain may be involved in neurodegeneration. Using a mouse model that expresses the pathological P301S human tau (PS19 mouse), we found reduced tauopathy and microgliosis in 6- to 7-mo-old PS19 mice lacking TMEM16F. Furthermore, this reduction of pathology can be recapitulated in the PS19 mice with TMEM16F removed from neurons, while removal of TMEM16F from microglia of PS19 mice did not significantly impact tauopathy at this time point. Moreover, TMEM16F mediated aberrant phosphatidylserine exposure in neurons with phospho-tau burden. These studies raise the prospect of targeting TMEM16F in neurons as a potential treatment of neurodegeneration.
Topics: Animals; Anoctamins; Phosphatidylserines; Neurons; tau Proteins; Mice; Tauopathies; Humans; Microglia; Phosphorylation; Mice, Transgenic; Disease Models, Animal; Phospholipid Transfer Proteins; Brain; Mice, Knockout
PubMed: 38941274
DOI: 10.1073/pnas.2311831121 -
ELife Jun 2024Homeostatic plasticity represents a set of mechanisms that are thought to recover some aspect of neural function. One such mechanism called AMPAergic scaling was thought...
Homeostatic plasticity represents a set of mechanisms that are thought to recover some aspect of neural function. One such mechanism called AMPAergic scaling was thought to be a likely candidate to homeostatically control spiking activity. However, recent findings have forced us to reconsider this idea as several studies suggest AMPAergic scaling is not directly triggered by changes in spiking. Moreover, studies examining homeostatic perturbations have suggested that GABAergic synapses may be more critical in terms of spiking homeostasis. Here, we show results that GABAergic scaling can act to homeostatically control spiking levels. We found that perturbations which increased or decreased spiking in cortical cultures triggered multiplicative GABAergic upscaling and downscaling, respectively. In contrast, we found that changes in AMPA receptor (AMPAR) or GABAR transmission only influence GABAergic scaling through their indirect effect on spiking. We propose that GABAergic scaling represents a stronger candidate for spike rate homeostat than AMPAergic scaling.
Topics: Receptors, AMPA; Animals; Action Potentials; Synapses; Neuronal Plasticity; GABAergic Neurons; Synaptic Transmission; Cells, Cultured; gamma-Aminobutyric Acid; Homeostasis
PubMed: 38941139
DOI: 10.7554/eLife.87753 -
Cellular and Molecular Life Sciences :... Jun 2024As human skin comes into contact with the tiny hairs or setae of the oak processionary caterpillar, Thaumetopoea processionea, a silent yet intense chemical...
As human skin comes into contact with the tiny hairs or setae of the oak processionary caterpillar, Thaumetopoea processionea, a silent yet intense chemical confrontation occurs. The result is a mix of issues: skin rashes and an intense itching that typically lasts days and weeks after the contact. This discomfort poses a significant health threat not only to humans but also to animals. In Western Europe, the alarming increase in outbreaks extends beyond areas near infested trees due to the dispersion of the setae. Predictions indicate a sustained rise in outbreaks, fueled by global changes favoring the caterpillar's survival and distribution. Currently, the absence of an efficient treatment persists due to significant gaps in our comprehension of the pathophysiology associated with this envenomation. Here, we explored the interaction between the venom extract derived from the setae of T. processionea and voltage- and ligand-gated ion channels and receptors. By conducting electrophysiological analyses, we discovered ex vivo evidence highlighting the significant role of TPTX-Tp1, a peptide toxin from T. processionea, in modulating TRPV1. TPTX-Tp1 is a secapin-like peptide and demonstrates a unique ability to modulate TRPV1 channels in the presence of capsaicin, leading to cell depolarization, itch and inflammatory responses. This discovery opens new avenues for developing a topical medication, suggesting the incorporation of a TRPV1 blocker as a potential solution for the local effects caused by T. processionea.
Topics: TRPV Cation Channels; Animals; Humans; Arthropod Venoms; Moths; Skin; Larva
PubMed: 38940922
DOI: 10.1007/s00018-024-05318-9 -
Cancer Medicine Jul 2024Nucleoporin 98 (NUP98) fusion proteins are recurrently found in leukemia and are associated with unfavorable clinical outcomes. They are distributed to the nucleus and...
INTRODUCTION
Nucleoporin 98 (NUP98) fusion proteins are recurrently found in leukemia and are associated with unfavorable clinical outcomes. They are distributed to the nucleus and contribute to leukemogenesis via aberrant transcriptional regulation. We previously identified NUP98-BPTF (NB) fusion in patients with T-cell acute lymphoblastic leukemia (T-ALL) using next-generation sequencing. The FG-repeat of NUP98 and the PHD finger and bromodomain of bromodomain PHD finger transcription factor (BPTF) are retained in the fusion. Like other NUP98 fusion proteins, NB is considered to regulate genes that are essential for leukemogenesis. However, its target genes or pathways remain unknown.
MATERIALS AND METHODS
To investigate the potential oncogenic properties of the NB fusion protein, we lentivirally transduced a doxycycline-inducible NB expression vector into mouse NIH3T3 fibroblasts and human Jurkat T-ALL cells.
RESULTS
NB promoted the transformation of mouse NIH3T3 fibroblasts by upregulating the proto-oncogene Pim1, which encodes a serine/threonine kinase. NB transcriptionally regulated Pim1 expression by binding to its promoter and activated MYC and mTORC1 signaling. PIM1 knockdown or pharmacological inhibition of mTORC1 signaling suppressed NB-induced NIH3T3 cell transformation. Furthermore, NB enhanced the survival of human Jurkat T-ALL cells by inactivating the pro-apoptotic protein BCL2-associated agonist of cell death (BAD).
CONCLUSION
We demonstrated the pivotal role of NB in cell transformation and survival and identified PIM1as a key downstream target of NB. These findings propose a promising therapeutic strategy for patients with NB fusion-positive leukemia.
Topics: Humans; Proto-Oncogene Proteins c-pim-1; Animals; Mice; Cell Transformation, Neoplastic; Nuclear Pore Complex Proteins; Oncogene Proteins, Fusion; Jurkat Cells; Up-Regulation; NIH 3T3 Cells; Proto-Oncogene Mas; Transcription Factors; Apoptosis; Cell Proliferation
PubMed: 38940430
DOI: 10.1002/cam4.7445 -
ACS Biomaterials Science & Engineering Jun 2024Exosomes are nanoscale membrane bound vesicles secreted by almost all types of cells. Their unique attributes, such as minimal immunogenicity and compatibility with... (Review)
Review
Exosomes are nanoscale membrane bound vesicles secreted by almost all types of cells. Their unique attributes, such as minimal immunogenicity and compatibility with biological systems, make them novel carriers for drug delivery. These native exosomes harbor proteins, nucleic acids, small molecule compounds, and fluorogenic agents. Moreover, through a combination of chemical and bioengineering methodologies, exosomes are tailored to transport precise therapeutic payloads to designated cells or tissues. In this review, we summarize the strategies for exosome modification and drug loading modalities in engineered exosomes. In addition, we provide an overview of the advances in the use of engineered exosomes for targeted drug delivery. Lastly, we discuss the merits and limitations of chemically engineered versus bioengineered exosome-mediated target therapies. These insights offer additional options for refining engineered exosomes in pharmaceutical development and hold promise for expediting the successful translation of engineered exosomes from the bench to the bedside.
PubMed: 38940421
DOI: 10.1021/acsbiomaterials.4c00856 -
Molecular Medicine Reports Aug 2024Elevated levels of blood glucose in patients with ischemic stroke are associated with a worse prognosis. The present study aimed to explore whether hyperglycemia...
Elevated levels of blood glucose in patients with ischemic stroke are associated with a worse prognosis. The present study aimed to explore whether hyperglycemia promotes microglial pyroptosis by increasing the oxygen extraction rate in an acute ischemic stroke model. C57BL/6 mice that underwent middle cerebral artery occlusion were used for assessment of blood glucose level and neurological function. The cerebral oxygen extraction ratio (CERO), oxygen consumption rate (OCR) and partial pressure of brain tissue oxygen (PbtO) were measured. To investigate the significance of the NOD‑like receptor protein 3 (NLRP3) inflammasome, NLRP3 mice were used, and the expression levels of NLRP3, caspase‑1, full‑length gasdermin D (GSDMD‑FL), GSDMD‑N domain (GSDMD‑N), IL‑1β and IL‑18 were evaluated. In addition, Z‑YVAD‑FMK, a caspase‑1 inhibitor, was used to treat microglia to determine whether activation of the NLRP3 inflammasome was required for the enhancing effect of hyperglycemia on pyroptosis. It was revealed that hyperglycemia accelerated cerebral injury in the acute ischemic stroke model, as evidenced by decreased latency to fall and the percentage of foot fault. Hyperglycemia aggravated hypoxia by increasing the oxygen extraction rate, as evidenced by increased CERO and OCR, and decreased PbtO in response to high glucose treatment. Furthermore, hyperglycemia‑induced microglial pyroptosis was confirmed by detection of increased levels of caspase‑1, GSDMD‑N, IL‑1β and IL‑18 and a decreased level of GSDMD‑FL. However, the knockout of NLRP3 attenuated these effects. Pharmacological inhibition of caspase‑1 also reduced the expression levels of GSDMD‑N, IL‑1β and IL‑18 in microglial cells. These results suggested that hyperglycemia stimulated NLRP3 inflammasome activation by increasing the oxygen extraction rate, thus leading to the aggravation of pyroptosis following ischemic stroke.
Topics: Animals; Pyroptosis; Microglia; Ischemic Stroke; Mice; NLR Family, Pyrin Domain-Containing 3 Protein; Oxygen; Male; Hyperglycemia; Inflammasomes; Mice, Inbred C57BL; Caspase 1; Disease Models, Animal; Mice, Knockout; Interleukin-1beta; Phosphate-Binding Proteins; Oxygen Consumption; Gasdermins
PubMed: 38940333
DOI: 10.3892/mmr.2024.13270