-
Food Research International (Ottawa,... Aug 2024Comprehensive lipid and volatile compound analyses were performed with squids collected from four varied geographical locations to discriminate the regional...
Lipidomics profile and volatile compounds of squids (Illex argentinus, Ommastrephes Bartram and Dosidicus gigas) in the Argentine, North Pacific Ocean, Equator and Peru by UPLC-triple TOF-MS and HS-SPME-GC-O-MS.
Comprehensive lipid and volatile compound analyses were performed with squids collected from four varied geographical locations to discriminate the regional characteristics. A total of 1442 lipid molecules and 110 volatiles were detected in the squid muscle samples. There were significant differences in the lipid profiles between Argentine squid (Illex argentinus, AGT), North Pacific Ocean squid (Ommastrephes Bartram, NPO), Equatorial squid (Dosidicus gigas, EQ), and Peruvian squid (Dosidicus gigas, PR) muscle. Phosphatidylcholines (14.64%), triacylglycerols (12.42%), and ceramides (10.97%) were the main lipid components. The contents of polyunsaturated fatty acid in phospholipids and in glycerolipids were 30.35-52.05% and 18.11-25.15%, respectively. The volatiles in squids exhibited significant regional variation; 1-pentanol and 1-octanol, 2-ethyl-1-hexanol and terpinen-4-ol, 2,7-ethyl-1-hexanol, 3-methy-1-butanol and 2-propyl-1-pentanol were identified as characteristic flavor compounds in AGT, NPO, EQ, and PR, respectively. Sphingomyelin, phosphatidylserine, phosphatidylethanolamine, and ceramide were strongly correlated with volatiles in squid muscle. Our study is a reference for the lipid nutritional value and flavor compounds of squids.
Topics: Animals; Decapodiformes; Volatile Organic Compounds; Pacific Ocean; Lipidomics; Gas Chromatography-Mass Spectrometry; Argentina; Peru; Chromatography, High Pressure Liquid; Solid Phase Microextraction; Triglycerides; Lipids; Phospholipids; Muscles
PubMed: 38876608
DOI: 10.1016/j.foodres.2024.114559 -
Autophagy Jul 2024Thoracic aortic dissection (TAD) is a severe disease, characterized by numerous apoptotic vascular smooth muscle cells (VSMCs). EDIL3/Del-1 is a secreted protein...
Thoracic aortic dissection (TAD) is a severe disease, characterized by numerous apoptotic vascular smooth muscle cells (VSMCs). EDIL3/Del-1 is a secreted protein involved in macrophage efferocytosis in acute inflammation. Here, we aimed to investigate whether EDIL3 promoted the internalization and degradation of apoptotic VSMCs during TAD. The levels of EDIL3 were decreased in the serum and aortic tissue from TAD mice. Global knockout () mice and bone marrow chimeric mice exhibited a considerable exacerbation in β-aminopropionitrile monofumarate (BAPN)-induced TAD, accompanied with increased apoptotic VSMCs accumulating in the damaged aortic tissue. Two types of phagocytes, RAW264.7 cells and bone marrow-derived macrophages (BMDMs) were used for in vitro efferocytosis assay. -deficient phagocytes exhibited inefficient internalization and degradation of apoptotic VSMCs. Instead, EDIL3 promoted the internalization phase through interacting with phosphatidylserine (PtdSer) on apoptotic VSMCs and binding to the macrophage ITGAV/α-ITGB3/β integrin. In addition, EDIL3 accelerated the degradation phase through activating LC3-associated phagocytosis (LAP). Mechanically, following the engulfment, EDIL3 enhanced the activity of SMPD1/acid sphingomyelinase in the phagosome through blocking ITGAV-ITGB3 integrin, which facilitates phagosomal reactive oxygen species (ROS) production by NAPDH oxidase CYBB/NOX2. Furthermore, exogenous EDIL3 supplementation alleviated BAPN-induced TAD and promoted apoptotic cell clearance. EDIL3 may be a novel factor for the prevention and treatment of TAD. BAPN: β-aminopropionitrile monofumarate; BMDM: bone marrow-derived macrophage; C12FDG: 5-dodecanoylaminofluorescein-di-β-D-galactopyranoside; CTRL: control; CYBB/NOX2: cytochrome b-245, beta polypeptide; DCFH-DA: 2',7'-dichlorofluorescin diacetate; EDIL3/Del-1: EGF-like repeats and discoidin I-like domains 3; EdU: 5-ethynyl-2'-deoxyuridine; EVG: elastic van Gieson; H&E: hematoxylin and eosin; IL: interleukin; LAP: LC3-associated phagocytosis; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; NAC: N-acetylcysteine; PtdSer: phosphatidylserine; rEDIL3: recombinant EDIL3; ROS: reactive oxygen species; SMPD1: sphingomyelin phosphodiesterase 1; TAD: thoracic aortic dissection; TEM: transmission electron microscopy; VSMC: vascular smooth muscle cell; WT: wild-type.
PubMed: 38873925
DOI: 10.1080/15548627.2024.2367191 -
The multifunction effector Vice stimulates macropinocytosis and interferes with the ESCRT machinery.Proceedings of the National Academy of... Jun 2024Intracellular bacterial pathogens divert multiple cellular pathways to establish their niche and persist inside their host. , the causative agent of Q fever, secretes...
Intracellular bacterial pathogens divert multiple cellular pathways to establish their niche and persist inside their host. , the causative agent of Q fever, secretes bacterial effector proteins via its Type 4 secretion system to generate a -containing vacuole (CCV). Manipulation of lipid and protein trafficking by these effectors is essential for bacterial replication and virulence. Here, we have characterized the lipid composition of CCVs and found that the effector Vice interacts with phosphoinositides and membranes enriched in phosphatidylserine and lysobisphosphatidic acid. Remarkably, eukaryotic cells ectopically expressing Vice present compartments that resemble early CCVs in both morphology and composition. We found that the biogenesis of these compartments relies on the double function of Vice. The effector protein initially localizes at the plasma membrane of eukaryotic cells where it triggers the internalization of large vacuoles by macropinocytosis. Then, Vice stabilizes these compartments by perturbing the ESCRT machinery. Collectively, our results reveal that Vice is an essential effector protein capable of hijacking two major cellular pathways to shape the bacterial replicative niche.
Topics: Endosomal Sorting Complexes Required for Transport; Pinocytosis; Bacterial Proteins; Coxiella burnetii; Vacuoles; Humans; HeLa Cells; Cell Membrane; Animals; Phosphatidylinositols
PubMed: 38870060
DOI: 10.1073/pnas.2315481121 -
Biomedical Optics Express Jun 2024The activation of astrocytes derived from induced pluripotent stem cells (iPSCs) is of great significance in neuroscience research, and it is crucial to obtain both...
The activation of astrocytes derived from induced pluripotent stem cells (iPSCs) is of great significance in neuroscience research, and it is crucial to obtain both cellular morphology and biomolecular information non-destructively in situ, which is still complicated by the traditional optical microscopy and biochemical methods such as immunofluorescence and western blot. In this study, we combined digital holographic microscopy (DHM) and surface-enhanced Raman scattering (SERS) to investigate the activation characteristics of iPSCs-derived astrocytes. It was found that the projected area of activated astrocytes decreased by 67%, while the cell dry mass increased by 23%, and the cells changed from a flat polygonal shape to an elongated star-shaped morphology. SERS analysis further revealed an increase in the intensities of protein spectral peaks (phenylalanine 1001 cm, proline 1043 cm, etc.) and lipid-related peaks (phosphatidylserine 524 cm, triglycerides 1264 cm, etc.) decreased in intensity. Principal component analysis-linear discriminant analysis (PCA-LDA) modeling based on spectral data distinguished resting and reactive astrocytes with a high accuracy of 96.5%. The increase in dry mass correlated with the increase in protein content, while the decrease in projected area indicated the adjustment of lipid composition and cell membrane remodeling. Importantly, the results not only reveal the cellular morphology and molecular changes during iPSCs-derived astrocytes activation but also reflect their mapping relationship, thereby providing new insights into diagnosing and treating neurodegenerative diseases.
PubMed: 38867782
DOI: 10.1364/BOE.524356 -
Biological & Pharmaceutical Bulletin 2024Ceramide (Cer) is synthesized de novo in the bilayer of the endoplasmic reticulum and transported to the cytosolic leaflet of the trans-Golgi apparatus for sphingomyelin...
Ceramide (Cer) is synthesized de novo in the bilayer of the endoplasmic reticulum and transported to the cytosolic leaflet of the trans-Golgi apparatus for sphingomyelin (SM) synthesis. As the active site of SM synthase (SMS) is located on the luminal side of the Golgi membrane, Cer translocates to the lumen via transbilayer movement for SM synthesis. However, the mechanism of transbilayer movement is not fully understood. As the Cer-related translocases seem to localize near the SMS, the protein was identified using proximity-dependent biotin identification proteomics. Phospholipid scramblase 1 (PLSCR1), which is thought to act as a scramblase for phosphatidylserine and phosphatidylethanolamine, was identified as a protein proximal to the SMS isoforms SMS1 and SMS2. Although five isoforms of PLSCR have been reported in humans, only PLSCR1, PLSCR3, and PLSCR4 are expressed in HEK293T cells. Confocal microscopic analysis showed that PLSCR1 and PLSCR4 partially co-localized with p230, a trans-Golgi network marker, where SMS isoforms are localized. We established CRISPR/Cas9-mediated PLSCR1, PLSCR3, and PLSCR4 single-knockout cells and PLSCR1, 3, 4 triple knockout HEK293T cells. Liquid chromatography-tandem mass spectrometry revealed that the levels of species with distinct acyl chains in Cer and SM were not significantly different in single knockout cells or in the triple knockout cells compared to the wild-type cells. Our findings suggest that PLSCR1 is localized in the vicinity of SMS isoforms, however is not involved in the transbilayer movement of Cer for SM synthesis.
Topics: Humans; Phospholipid Transfer Proteins; Transferases (Other Substituted Phosphate Groups); HEK293 Cells; Sphingomyelins; Membrane Proteins; Isoenzymes; Golgi Apparatus
PubMed: 38866522
DOI: 10.1248/bpb.b24-00177 -
The Journal of Biological Chemistry Jun 2024Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a lipid-enveloped virus that acquires its lipid bilayer from the host cell it infects. SARS-CoV-2 can...
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a lipid-enveloped virus that acquires its lipid bilayer from the host cell it infects. SARS-CoV-2 can spread from cell to cell or from patient to patient by undergoing assembly and budding to form new virions. The assembly and budding of SARS-CoV-2 is mediated by several structural proteins known as envelope (E), membrane (M), nucleoprotein (N) and spike (S), which can form virus-like particles (VLPs) when co-expressed in mammalian cells. Assembly and budding of SARS-CoV-2 from the host ER-Golgi intermediate compartment is a critical step in the virus acquiring its lipid bilayer. To date, little information is available on how SARS-CoV-2 assembles and forms new viral particles from host membranes. In this study, we used several lipid binding assays and found the N protein can strongly associate with anionic lipids including phosphoinositides and phosphatidylserine. Moreover, we show lipid binding occurs in the N protein C-terminal domain, which is supported by extensive in silico analysis. We demonstrate anionic lipid binding occurs for both the free and N oligomeric forms, suggesting N can associate with membranes in the nucleocapsid form. Based on these results, we present a lipid-dependent model based on in vitro, cellular and in silico data for the recruitment of N to assembly sites in the lifecycle of SARS-CoV-2.
PubMed: 38866325
DOI: 10.1016/j.jbc.2024.107456 -
International Journal of Nanomedicine 2024Current immunotherapies with unexpected severe side effects and treatment resistance have not resulted in the desired outcomes for patients with melanoma, and there is a...
BACKGROUND
Current immunotherapies with unexpected severe side effects and treatment resistance have not resulted in the desired outcomes for patients with melanoma, and there is a need to discover more effective medications. Cytotoxin (CTX) from has been established to have favorable cytolytic activity and antitumor efficacy and is regarded as a promising novel anticancer agent. However, amphiphilic CTX with excellent anionic phosphatidylserine lipid-binding ability may also damage normal cells.
METHODS
We developed pH-responsive liposomes with a high CTX load (CTX@PSL) for targeted acidic-stimuli release of drugs in the tumor microenvironment. The morphology, size, zeta potential, drug-release kinetics, and preservation stability were characterized. Cell uptake, apoptosis-promoting effects, and cytotoxicity were assessed using MTT assay and flow cytometry. Finally, the tissue distribution and antitumor effects of CTX@PSL were systematically assessed using an in vivo imaging system.
RESULTS
CTX@PSL exhibited high drug entrapment efficiency, drug loading, stability, and a rapid release profile under acidic conditions. These nanoparticles, irregularly spherical in shape and small in size, can effectively accumulate at tumor sites (six times higher than free CTX) and are rapidly internalized into cancer cells (2.5-fold higher cell uptake efficiency). CTX@PSL displayed significantly stronger cytotoxicity (IC 0.25 μg/mL) and increased apoptosis in than the other formulations (apoptosis rate 71.78±1.70%). CTX@PSL showed considerably better tumor inhibition efficacy than free CTX or conventional liposomes (tumor inhibition rate 79.78±5.93%).
CONCLUSION
Our results suggest that CTX@PSL improves tumor-site accumulation and intracellular uptake for sustained and targeted CTX release. By combining the advantages of CTX and stimuli-responsive nanotechnology, the novel CTX@PSL nanoformulation is a promising therapeutic candidate for cancer treatment.
Topics: Liposomes; Hydrogen-Ion Concentration; Animals; Elapid Venoms; Humans; Cell Line, Tumor; Antineoplastic Agents; Mice; Apoptosis; Drug Liberation; Cytotoxins; Drug Delivery Systems; Tissue Distribution; Tumor Microenvironment; Nanoparticles
PubMed: 38859950
DOI: 10.2147/IJN.S461728 -
Biochimie Jun 2024Uropathogenic strains of E. coli (UPEC) is a leading cause of sepsis, deploying multiple virulence factors to evade host immune responses. Notably, alpha-hemolysin...
Uropathogenic strains of E. coli (UPEC) is a leading cause of sepsis, deploying multiple virulence factors to evade host immune responses. Notably, alpha-hemolysin (HlyA) produced by UPEC is implicated in septic symptoms associated with bacteremia, correlating with thrombocytopenia, a critical indicator of organ dysfunction and a predictor of poorer patient prognosis. This study meticulously explores the impact of sublytic concentrations of HlyA on platelets. Findings reveal that HlyA triggers an increase in intracellular calcium, activating calpain and exposing phosphatidylserine to the cell surface, as validated by flow cytometric experiments. Electron microscopy reveals a distinctive balloon-like shape in HlyA-treated platelets, indicative of a procoagulant state. The toxin induces the release of procoagulant extracellular vesicles and the secretion of alpha and dense granules. Overall, the results point to HlyA inducing a necrotic-like procoagulant state in platelets. The effects of sublytic concentrations of HlyA on both erythrocytes and platelets could have a potential impact on capillary microcirculation. Targeting HlyA emerges as a viable therapeutic strategy to mitigate the adverse effects of UPEC infections, especially in South American countries where these infections are endemic, underscoring its significance as a potential therapeutic target.
PubMed: 38857695
DOI: 10.1016/j.biochi.2024.06.001 -
Bioactive Materials Sep 2024Retinal neovascularization (RNV), a typical pathological manifestation involved in most neovascular diseases, causes retinal detachment, vision loss, and ultimately...
Retinal neovascularization (RNV), a typical pathological manifestation involved in most neovascular diseases, causes retinal detachment, vision loss, and ultimately irreversible blindness. Repeated intravitreal injections of anti-VEGF drugs were developed against RNV, with limitations of incomplete responses and adverse effects. Therefore, a new treatment with a better curative effect and more prolonged dosage is demanding. Here, we induced macrophage polarization to anti-inflammatory M2 phenotype by inhibiting cGAS-STING signaling with an antagonist C176, appreciating the role of cGAS-STING signaling in the retina in pro-inflammatory M1 polarization. C176-loaded and phosphatidylserine-modified dendritic mesoporous silica nanoparticles were constructed and examined by a single intravitreal injection. The biosafe nanoparticles were phagocytosed by retinal macrophages through a phosphatidylserine-mediated "eat me" signal, which persistently release C176 to suppress STING signaling and thereby promote macrophage M2 polarization specifically. A single dosage can effectively alleviate pathological angiogenesis phenotypes in murine oxygen-induced retinopathy models. In conclusion, these C176-loaded nanoparticles with enhanced cell uptake and long-lasting STING inhibition effects might serve as a promising way for treating RNV.
PubMed: 38855060
DOI: 10.1016/j.bioactmat.2024.05.038 -
BioRxiv : the Preprint Server For... May 2024Phosphatidylinositol phosphates (PIPs) are a family of seven different eukaryotic membrane lipids that have a large role in cell viability, despite their minor...
Phosphatidylinositol phosphates (PIPs) are a family of seven different eukaryotic membrane lipids that have a large role in cell viability, despite their minor concentration in eukaryotic cellular membranes. PIPs tightly regulate cellular processes such as cellular growth, metabolism, immunity, and development through direct interactions with partner proteins. Understanding the biophysical properties of PIPs in the complex membrane environment is important to understand how PIPs selectively regulate a partner protein. Here we investigate the structure and dynamics of PIP3 in lipid bilayers that are simplified models of the natural membrane environment. We probe the effects of the anionic lipid phosphatidylserine (PS) and the divalent cation Ca . We use solution and solid-state H, P, and C NMR all at natural abundance combined with MD simulations to characterize the structure and dynamics of PIPs. H and P 1D spectra show good resolution at high temperatures with isolated peaks in the headgroup, interfacial, and bilayer regions. Site specific assignment of these 1D reporters were made and used to measure the effects of Ca and PS. In particular, the resolved P signals of the PIP3 headgroup allowed for extremely well localized information about PIP3 phosphate dynamics, which the MD simulations were able to help explain. Cross polarization kinetics provided additional site-specific dynamics measurements for the PIP3 headgroups.
PubMed: 38854128
DOI: 10.1101/2024.05.28.596302