1
|
Su D, Wang X, Liu X, Miao J, Zhang Z, Zhang Y, Zhao L, Yu Y, Leng K, Yu Y. A comprehensive study of the colloidal properties, biocompatibility, and synergistic antioxidant actions of Antarctic krill phospholipids. Food Chem 2024; 451:139469. [PMID: 38703727 DOI: 10.1016/j.foodchem.2024.139469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/22/2024] [Accepted: 04/22/2024] [Indexed: 05/06/2024]
Abstract
Excipient selection is crucial to address the oxidation and solubility challenges of bioactive substances, impacting their safety and efficacy. AKPL, a novel ω-3 polyunsaturated fatty acids (PUFAs) esterified phospholipid derived from Antarctic krill, demonstrates unique antioxidant capabilities and synergistic effects. It exhibits pronounced surface activity and electronegativity at physiological pH, as evidenced by a critical micelle concentration (CMC) of 0.15 g/L and ζ-potential of -49.9 mV. In aqueous environments, AKPL self-assembles into liposomal structures, offering high biocompatibility and promoting cell proliferation. Its polyunsaturated bond-rich structure provides additional oxidation sites, imparting antioxidant properties superior to other phospholipids like DSPC and DOPC. Additionally, AKPL augments the efficacy of lipophilic antioxidants, such as alpha-tocopherol and curcumin, in aqueous media through both intermolecular and intramolecular interactions. In sum, AKPL emerges as an innovative unsaturated phospholipid, offering new strategies for encapsulating and delivering oxygen-sensitive agents.
Collapse
Affiliation(s)
- Dong Su
- State Key Laboratory of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China; Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Qingdao 266071, PR China
| | - Xixi Wang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Qingdao 266071, PR China
| | - Xiaofang Liu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Qingdao 266071, PR China
| | - Junkui Miao
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Qingdao 266071, PR China
| | - Zipeng Zhang
- State Key Laboratory of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Yating Zhang
- State Key Laboratory of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Ling Zhao
- State Key Laboratory of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Yuan Yu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Qingdao 266071, PR China
| | - Kailiang Leng
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Qingdao 266071, PR China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No.1 Wenhai Road, Qingdao 266200, China.
| | - Yueqin Yu
- State Key Laboratory of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
| |
Collapse
|
2
|
Abeyawardhane DL, Sevdalis SE, Adipietro KA, Godoy-Ruiz R, Varney KM, Nawaz IF, Spittel AX, Rustandi RR, Silin VI, des Georges A, Pozharski E, Weber DJ. Membrane binding and pore formation is Ca 2+ -dependent for the Clostridioides difficile binary toxin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.18.553786. [PMID: 37645845 PMCID: PMC10462154 DOI: 10.1101/2023.08.18.553786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The C. difficile binary toxin (CDT) enters host cells via endosomal delivery like many other 'AB'-type binary toxins. In this study, the cell-binding component of CDT, termed CDTb, was found to bind and form pores in lipid bilayers upon depleting free Ca 2+ ion concentrations, and not by lowering pH, as found for other binary toxins (i.e., anthrax). Cryoelectron microscopy, nuclear magnetic resonance spectroscopy, surface plasmon resonance, electrochemical impedance spectroscopy, CDT toxicity studies, and site directed mutagenesis show that dissociation of Ca 2+ from a single site in receptor binding domain 1 (RBD1) of CDTb is consistent with a molecular mechanism in which Ca 2+ dissociation from RBD1 induces a "trigger" via conformational exchange that enables CDTb to bind and form pores in endosomal membrane bilayers as free Ca 2+ concentrations decrease during CDT endosomal delivery.
Collapse
|
3
|
Hoogerheide DP, Dura JA, Maranville BB, Majkrzak CF. Low-background neutron reflectometry from solid/liquid interfaces. J Appl Crystallogr 2022. [DOI: 10.1107/s1600576721011924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Liquid cells are an increasingly common sample environment for neutron reflectometry experiments and are critical for measuring the properties of materials at solid/liquid interfaces. Background scattering determines the maximum useful scattering vector, and hence the spatial resolution, of the neutron reflectometry measurement. The primary sources of background are the liquid in the cell reservoir and the materials forming the liquid cell itself. Thus, characterization and mitigation of these background sources are necessary for improvements in the signal-to-background ratio and resolution of neutron reflectometry measurements employing liquid cells. Single-crystal silicon is a common material used for liquid cells due to its low incoherent scattering cross section for neutrons, and the path lengths of the neutron beam through silicon can be several centimetres in modern cell designs. Here, a liquid cell is constructed with a sub-50 µm thick liquid reservoir encased in single-crystal silicon. It is shown that, at high scattering vectors, inelastic scattering from silicon represents a significant portion of the scattering background and is, moreover, structured, confounding efforts to correct for it by established background subtraction techniques. A significant improvement in the measurement quality is achieved using energy-analyzed detection. Energy-analyzed detection reduces the scattering background from silicon by nearly an order of magnitude, and from fluids such as air and liquids by smaller but significant factors. Combining thin liquid reservoirs with energy-analyzed detection and the high flux of the CANDOR polychromatic reflectometer at the NIST Center for Neutron Research, a background-subtracted neutron reflectivity smaller than 10−8 from a liquid cell sample is reported.
Collapse
|
4
|
Ma C, Martinez-Rodriguez V, Hoffmann PR. Roles for Selenoprotein I and Ethanolamine Phospholipid Synthesis in T Cell Activation. Int J Mol Sci 2021; 22:ijms222011174. [PMID: 34681834 PMCID: PMC8540796 DOI: 10.3390/ijms222011174] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 12/24/2022] Open
Abstract
The selenoprotein family includes 25 members, many of which are antioxidant or redox regulating enzymes. A unique member of this family is Selenoprotein I (SELENOI), which does not catalyze redox reactions, but instead is an ethanolamine phosphotransferase (Ept). In fact, the characteristic selenocysteine residue that defines selenoproteins lies far outside of the catalytic domain of SELENOI. Furthermore, data using recombinant SELENOI lacking the selenocysteine residue have suggested that the selenocysteine amino acid is not directly involved in the Ept reaction. SELENOI is involved in two different pathways for the synthesis of phosphatidylethanolamine (PE) and plasmenyl PE, which are constituents of cellular membranes. Ethanolamine phospholipid synthesis has emerged as an important process for metabolic reprogramming that occurs in pluripotent stem cells and proliferating tumor cells, and this review discusses roles for upregulation of SELENOI during T cell activation, proliferation, and differentiation. SELENOI deficiency lowers but does not completely diminish de novo synthesis of PE and plasmenyl PE during T cell activation. Interestingly, metabolic reprogramming in activated SELENOI deficient T cells is impaired and this reduces proliferative capacity while favoring tolerogenic to pathogenic phenotypes that arise from differentiation. The implications of these findings are discussed related to vaccine responses, autoimmunity, and cell-based therapeutic approaches.
Collapse
|