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1.
PLoS Pathog ; 20(4): e1011750, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38574119

RESUMO

Rotaviruses infect cells by delivering into the cytosol a transcriptionally active inner capsid particle (a "double-layer particle": DLP). Delivery is the function of a third, outer layer, which drives uptake from the cell surface into small vesicles from which the DLPs escape. In published work, we followed stages of rhesus rotavirus (RRV) entry by live-cell imaging and correlated them with structures from cryogenic electron microscopy and tomography (cryo-EM and cryo-ET). The virus appears to wrap itself in membrane, leading to complete engulfment and loss of Ca2+ from the vesicle produced by the wrapping. One of the outer-layer proteins, VP7, is a Ca2+-stabilized trimer; loss of Ca2+ releases both VP7 and the other outer-layer protein, VP4, from the particle. VP4, activated by cleavage into VP8* and VP5*, is a trimer that undergoes a large-scale conformational rearrangement, reminiscent of the transition that viral fusion proteins undergo to penetrate a membrane. The rearrangement of VP5* thrusts a 250-residue, C-terminal segment of each of the three subunits outward, while allowing the protein to remain attached to the virus particle and to the cell being infected. We proposed that this segment inserts into the membrane of the target cell, enabling Ca2+ to cross. In the work reported here, we show the validity of key aspects of this proposed sequence. By cryo-EM studies of liposome-attached virions ("triple-layer particles": TLPs) and single-particle fluorescence imaging of liposome-attached TLPs, we confirm insertion of the VP4 C-terminal segment into the membrane and ensuing generation of a Ca2+ "leak". The results allow us to formulate a molecular description of early events in entry. We also discuss our observations in the context of other work on double-strand RNA virus entry.


Assuntos
Rotavirus , Rotavirus/genética , Proteínas do Capsídeo/metabolismo , Capsídeo/metabolismo , Cálcio/metabolismo , Lipossomos/análise , Lipossomos/metabolismo
2.
J Cell Biol ; 223(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38587486

RESUMO

ß-Coronaviruses remodel host endomembranes to form double-membrane vesicles (DMVs) as replication organelles (ROs) that provide a shielded microenvironment for viral RNA synthesis in infected cells. DMVs are clustered, but the molecular underpinnings and pathophysiological functions remain unknown. Here, we reveal that host fragile X-related (FXR) family proteins (FXR1/FXR2/FMR1) are required for DMV clustering induced by expression of viral non-structural proteins (Nsps) Nsp3 and Nsp4. Depleting FXRs results in DMV dispersion in the cytoplasm. FXR1/2 and FMR1 are recruited to DMV sites via specific interaction with Nsp3. FXRs form condensates driven by liquid-liquid phase separation, which is required for DMV clustering. FXR1 liquid droplets concentrate Nsp3 and Nsp3-decorated liposomes in vitro. FXR droplets facilitate recruitment of translation machinery for efficient translation surrounding DMVs. In cells depleted of FXRs, SARS-CoV-2 replication is significantly attenuated. Thus, SARS-CoV-2 exploits host FXR proteins to cluster viral DMVs via phase separation for efficient viral replication.


Assuntos
COVID-19 , Proteína do X Frágil de Retardo Mental , Lipossomos , Proteínas de Ligação a RNA , SARS-CoV-2 , Humanos , Proliferação de Células , Análise por Conglomerados , COVID-19/metabolismo , COVID-19/virologia , Citoplasma , Proteína do X Frágil de Retardo Mental/metabolismo , Células HeLa , Lipossomos/metabolismo , Organelas , Proteínas de Ligação a RNA/metabolismo , Proteínas não Estruturais Virais/metabolismo
3.
J Nanobiotechnology ; 22(1): 156, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589867

RESUMO

Immunotherapy has revolutionized the treatment of cancer. However, its efficacy remains to be optimized. There are at least two major challenges in effectively eradicating cancer cells by immunotherapy. Firstly, cancer cells evade immune cell killing by down-regulating cell surface immune sensors. Secondly, immune cell dysfunction impairs their ability to execute anti-cancer functions. Radiotherapy, one of the cornerstones of cancer treatment, has the potential to enhance the immunogenicity of cancer cells and trigger an anti-tumor immune response. Inspired by this, we fabricate biofunctionalized liposome-like nanovesicles (BLNs) by exposing irradiated-cancer cells to ethanol, of which ethanol serves as a surfactant, inducing cancer cells pyroptosis-like cell death and facilitating nanovesicles shedding from cancer cell membrane. These BLNs are meticulously designed to disrupt both of the aforementioned mechanisms. On one hand, BLNs up-regulate the expression of calreticulin, an "eat me" signal on the surface of cancer cells, thus promoting macrophage phagocytosis of cancer cells. Additionally, BLNs are able to reprogram M2-like macrophages into an anti-cancer M1-like phenotype. Using a mouse model of malignant pleural effusion (MPE), an advanced-stage and immunotherapy-resistant cancer model, we demonstrate that BLNs significantly increase T cell infiltration and exhibit an ablative effect against MPE. When combined with PD-1 inhibitor (α-PD-1), we achieve a remarkable 63.6% cure rate (7 out of 11) among mice with MPE, while also inducing immunological memory effects. This work therefore introduces a unique strategy for overcoming immunotherapy resistance.


Assuntos
Lipossomos , Neoplasias , Humanos , Lipossomos/metabolismo , Neoplasias/radioterapia , Neoplasias/metabolismo , Macrófagos/metabolismo , Imunoterapia , Etanol/metabolismo , Linhagem Celular Tumoral
4.
Respir Res ; 25(1): 157, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594676

RESUMO

BACKGROUND: Environmental/occupational exposures cause significant lung diseases. Agricultural organic dust extracts (ODE) and bacterial component lipopolysaccharide (LPS) induce recruited, transitioning murine lung monocytes/macrophages, yet their cellular role remains unclear. METHODS: CCR2 RFP+ mice were intratracheally instilled with high concentration ODE (25%), LPS (10 µg), or gram-positive peptidoglycan (PGN, 100 µg) for monocyte/macrophage cell-trafficking studies. CCR2 knockout (KO) mice and administration of intravenous clodronate liposomes strategies were employed to reduce circulating monocytes available for lung recruitment following LPS exposure. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected. Pro-inflammatory and/or pro-fibrotic cytokines, chemokines, and lung extracellular matrix mediators were quantitated by ELISA. Infiltrating lung cells including monocyte/macrophage subpopulations, neutrophils, and lymphocytes were characterized by flow cytometry. Lung histopathology, collagen content, vimentin, and post-translational protein citrullination and malondialdehyde acetaldehyde (MAA) modification were quantitated. Parametric statistical tests (one-way ANOVA, Tukey'smultiple comparison) and nonparametric statistical (Kruskal-Wallis, Dunn's multiple comparison) tests were used following Shapiro-Wilk testing for normality. RESULTS: Intratracheal instillation of ODE, LPS, or PGN robustly induced the recruitment of inflammatory CCR2+ CD11cintCD11bhi monocytes/macrophages and both CCR2+ and CCR2- CD11c-CD11bhi monocytes at 48 h. There were also increases in CCR2+ CD4+ and CD8+ T cells and NK cells. Despite reductions in LPS-induced lung infiltrating CD11cintCD11bhi cells (54% reduction), CCR2 knockout (KO) mice were not protected against LPS-induced inflammatory and pro-fibrotic consequences. Instead, compensatory increases in lung neutrophils and CCL2 and CCL7 release occurred. In contrast, the depletion of circulating monocytes through the administration of intravenous clodronate (vs. vehicle) liposomes 24 h prior to LPS exposure reduced LPS-induced infiltrating CD11cintCD11bhi monocyte-macrophage subpopulation by 59% without compensatory changes in other cell populations. Clodronate liposome pre-treatment significantly reduced LPS-induced IL-6 (66% reduction), matrix metalloproteinases (MMP)-3 (36%), MMP-8 (57%), tissue inhibitor of metalloproteinases (61%), fibronectin (38%), collagen content (22%), and vimentin (40%). LPS-induced lung protein citrullination and MAA modification, post-translational modifications implicated in lung disease, were reduced (39% and 48%) with clodronate vs. vehicle liposome. CONCLUSION: Highly concentrated environmental/occupational exposures induced the recruitment of CCR2+ and CCR2- transitioning monocyte-macrophage and monocyte subpopulations and targeting peripheral monocytes may reduce the adverse lung consequences resulting from exposures to LPS-enriched inhalants.


Assuntos
Pneumopatias , Monócitos , Camundongos , Animais , Monócitos/metabolismo , Lipossomos/metabolismo , Vimentina/metabolismo , Lipopolissacarídeos/farmacologia , Ácido Clodrônico/farmacologia , Ácido Clodrônico/metabolismo , Linfócitos T CD8-Positivos , Pulmão , Macrófagos/metabolismo , Pneumopatias/metabolismo , Exposição Ambiental , Colágeno/metabolismo , Camundongos Endogâmicos C57BL
5.
ACS Synth Biol ; 13(4): 1355-1364, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38569139

RESUMO

Adenosine triphosphate (ATP)-producing modules energized by light-driven proton pumps are powerful tools for the bottom-up assembly of artificial cell-like systems. However, the maximum efficiency of such modules is prohibited by the random orientation of the proton pumps during the reconstitution process into lipid-surrounded nanocontainers. Here, we overcome this limitation using a versatile approach to uniformly orient the light-driven proton pump proteorhodopsin (pR) in liposomes. pR is post-translationally either covalently or noncovalently coupled to a membrane-impermeable protein domain guiding orientation during insertion into preformed liposomes. In the second scenario, we developed a novel bifunctional linker, trisNTA-SpyTag, that allows for the reversible connection of any SpyCatcher-containing protein and a HisTag-carrying protein. The desired protein orientations are verified by monitoring vectorial proton pumping and membrane potential generation. In conjunction with ATP synthase, highly efficient ATP production is energized by the inwardly pumping population. In comparison to other light-driven ATP-producing modules, the uniform orientation allows for maximal rates at economical protein concentrations. The presented technology is highly customizable and not limited to light-driven proton pumps but applicable to many membrane proteins and offers a general approach to overcome orientation mismatch during membrane reconstitution, requiring little to no genetic modification of the protein of interest.


Assuntos
Trifosfato de Adenosina , Lipossomos , Lipossomos/metabolismo , Trifosfato de Adenosina/metabolismo , Luz , Bombas de Próton/metabolismo , Proteínas de Membrana/metabolismo
6.
J Aerosol Med Pulm Drug Deliv ; 37(2): 100-110, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38640446

RESUMO

Inhalation of liposomes formulated with phospholipids similar to endogenous lung surfactants and lipids offers biocompatibility and versatility within the pulmonary medicine field to treat a range of diseases such as lung cancer, cystic fibrosis and lung infections. Manipulation of the physicochemical properties of liposomes enables innovative design of the carrier to meet specific delivery, release and targeting requirements. This delivery system offers several benefits: improved pharmacokinetics with reduced toxicity, enhanced therapeutic efficacy, increased delivery of poorly soluble drugs, taste masking, biopharmaceutics degradation protection and targeted cellular therapy. This section provides an overview of liposomal formulation and delivery, together with their applications for different disease states in the lung.


Assuntos
Lipossomos , Pneumonia , Humanos , Lipossomos/química , Lipossomos/metabolismo , Administração por Inalação , Pulmão/metabolismo , Fosfolipídeos , Sistemas de Liberação de Medicamentos
7.
Nat Commun ; 15(1): 2508, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509070

RESUMO

In the secretory pathway the destination of trafficking vesicles is determined by specific proteins that, with the notable exception of SNAREs, are recruited from soluble pools. Previously we have shown that microinjected proteoliposomes containing early or late endosomal SNAREs, respectively, are targeted to the corresponding endogenous compartments, with targeting specificity being dependent on the recruitment of tethering factors by some of the SNAREs. Here, we show that targeting of SNARE-containing liposomes is refined upon inclusion of polyphosphoinositides and Rab5. Intriguingly, targeting specificity is dependent on the concentration of PtdIns(3)P, and on the recruitment of PtdIns(3)P binding proteins such as rabenosyn-5 and PIKfyve, with conversion of PtdIns(3)P into PtdIns(3,5)P2 re-routing the liposomes towards late endosomes despite the presence of GTP-Rab5 and early endosomal SNAREs. Our data reveal a complex interplay between permissive and inhibitory targeting signals that sharpen a basic targeting and fusion machinery for conveying selectivity in intracellular membrane traffic.


Assuntos
Proteínas SNARE , Proteínas rab de Ligação ao GTP , Proteínas SNARE/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Fosfatidilinositóis/metabolismo , Lipossomos/metabolismo , Endossomos/metabolismo , Fusão de Membrana
8.
Int J Biol Macromol ; 265(Pt 1): 130641, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460623

RESUMO

Due to its involvement in skin maintenance and repair, topical administration of recombinant human growth hormone (rhGH) is an interesting strategy for therapeutic purposes. We have formulated and characterized a topical rhGH-loaded liposomal formulation (rhGH-Lip) and evaluated its safety, biological activity, and preventive role against UVB-induced skin damage. The rhGH-Lip had an average size and zeta potential of 63 nm and -33 mV, respectively, with 70 % encapsulation efficiency. The formulation was stable at 4 °C for at least one year. The SDS-PAGE and circular dichroism results showed no structural alterations in rhGH upon encapsulation. In vitro, studies in HaCaT, HFFF-2, and Ba/F3-rhGHR cell lines confirmed the safety and biological activity of rhGH-Lip. Franz diffusion cell study showed increased rhGH skin permeation compared to free rhGH. Animal studies in nude mice showed that liposomal rhGH prevented UVB-induced epidermal hyperplasia, angiogenesis, wrinkle formation, and collagen loss, as well as improving skin moisture. The results of this study show that rhGH-Lip is a stable, safe, and effective skin delivery system and has potential as an anti-wrinkle formulation for topical application. This study also provides a new method for the topical delivery of proteins and merits further investigation.


Assuntos
Hormônio do Crescimento Humano , Camundongos , Animais , Humanos , Hormônio do Crescimento Humano/farmacologia , Hormônio do Crescimento Humano/metabolismo , Camundongos Nus , Pele/metabolismo , Lipossomos/metabolismo , Absorção Cutânea
9.
J Phys Chem Lett ; 15(11): 3078-3088, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38467015

RESUMO

A biomimetic cell-based carrier system based on monocyte membranes and liposomes has been designed to create a hybrid "Monocyte-LP" which inherits the surface antigens of the monocytes along with the drug encapsulation property of the liposome. Förster resonance energy transfer (FRET) and polarization gated anisotropy measurements show the stiffness of the vesicles obtained from monocyte membranes (Mons), phosphatidylcholine membranes (LP), and Monocyte-LP to follow an increasing order of Mons > Monocyte-LP > LP. The dynamics of interface bound water molecules plays a key role in the elasticity of the vesicles, which in turn imparts higher delivery efficacy to the hybrid Monocyte-LP for a model anticancer drug doxorubicin than the other two vesicles, indicating a critical balance between flexibility and rigidity for an efficient cellular uptake. The present work provides insight on the influence of elasticity of delivery vehicles for enhanced drug delivery.


Assuntos
Antineoplásicos , Lipossomos , Lipossomos/metabolismo , Monócitos/metabolismo , Doxorrubicina , Sistemas de Liberação de Medicamentos
10.
Carbohydr Polym ; 332: 121844, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431385

RESUMO

Anti-viral and anti-tumor vaccines aim to induce cytotoxic CD8+ T cells (CTL) and antibodies. Conserved protein antigens, such as p24 from human immunodeficiency virus, represent promising component for elicitation CTLs, nevertheless with suboptimal immunogenicity, if formulated as recombinant protein. To enhance immunogenicity and CTL response, recombinant proteins may be targeted to dendritic cells (DC) for cross presentation on MHCI, where mannose receptor and/or other lectin receptors could play an important role. Here, we constructed liposomal carrier-based vaccine composed of recombinant p24 antigen bound by metallochelating linkage onto surface of nanoliposomes with surface mannans coupled by aminooxy ligation. Generated mannosylated proteonanoliposomes were analyzed by dynamic light scattering, isothermal titration, and electron microscopy. Using murine DC line MutuDC and murine bone marrow derived DC (BMDC) we evaluated their immunogenicity and immunomodulatory activity. We show that p24 mannosylated proteonanoliposomes activate DC for enhanced MHCI, MHCII and CD40, CD80, and CD86 surface expression both on MutuDC and BMDC. p24 mannosylated liposomes were internalized by MutuDC with p24 intracellular localization within 1 to 3 h. The combination of metallochelating and aminooxy ligation could be used simultaneously to generate nanoliposomal adjuvanted recombinant protein-based vaccines versatile for combination of recombinant antigens relevant for antibody and CTL elicitation.


Assuntos
Vacinas contra a AIDS , HIV-1 , Animais , Humanos , Camundongos , Antígenos , Células Dendríticas , Lipossomos/metabolismo , Mananas/metabolismo , Proteínas Recombinantes/metabolismo , Vacinas contra a AIDS/imunologia
11.
Mol Pharm ; 21(4): 2043-2057, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471114

RESUMO

The capillarization of hepatic sinusoids resulting from the activation of hepatic stellate cells poses a significant challenge, impeding the effective delivery of therapeutic agents to the Disse space for liver fibrosis treatment. Therefore, overcoming these barriers and achieving efficient drug delivery to activated hepatic stellate cells (aHSCs) are pressing challenge. In this study, we developed a synergistic sequential drug delivery approach utilizing neutrophil membrane hybrid liposome@atorvastatin/amlisentan (NCM@AtAm) and vitamin A-neutrophil membrane hybrid liposome @albumin (VNCM@Bai) nanoparticles (NPs) to breach the capillary barrier for targeted HSC cell delivery. Initially, NCM@AtAm NPs were successfully directed to the site of hepatic fibrosis through neutrophil-mediated inflammatory targeting, resulting in the normalization of liver sinusoidal endothelial cells (LSECs) and restoration of fenestrations under the combined influence of At and Am. Elevated tissue levels of the p-Akt protein and endothelial nitric oxide synthase (eNOS) indicated the normalization of LSECs following treatment with At and Am. Subsequently, VNCM@Bai NPs traversed the restored LSEC fenestrations to access the Disse space, facilitating the delivery of Bai into aHSCs under vitamin A guidance. Lastly, both in vitro and in vivo results demonstrated the efficacy of Bai in inhibiting HSC cell activation by modulating the PPAR γ/TGF-ß1 and STAT1/Smad7 signaling pathways, thereby effectively treating liver fibrosis. Overall, our designed synergistic sequential delivery system effectively overcomes the barrier imposed by LSECs, offering a promising therapeutic strategy for liver fibrosis treatment in clinical settings.


Assuntos
Células Endoteliais , Células Estreladas do Fígado , Humanos , Células Endoteliais/metabolismo , Biônica , Capilares/metabolismo , Lipossomos/metabolismo , Neutrófilos/metabolismo , Vitamina A/metabolismo , Vitamina A/farmacologia , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo
12.
J Control Release ; 368: 466-480, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38452820

RESUMO

Physiological or pathological hypoperfusion of the placenta is one of the main causes of intrauterine growth restriction (IUGR) which poses a significant risk to the health of the fetus and newborn. Tadalafil, a 5-type phosphodiesterase inhibitor, has previously been found to improve the symptoms of IUGR in various clinical studies. Unfortunately, its clinical utility is hindered by its limited water solubility, rapid metabolism, and lack of specific distribution in target tissues rendering tadalafil unable to maintain long-term placental perfusion. In this study, iRGD-modified tadalafil-loaded liposomes (iRGD-lipo@Tad) featuring a size of approximately 480 nm were designed to rectify the shortcomings of tadalafil. The prepared iRGD-lipo@Tad exhibited superior stability, sustained drug release capacity, and low cytotoxicity. The fluorescence study, tissue slice study, and drug biodistribution study together demonstrated the placenta-anchored ability of iRGD-modified liposomes. This was achieved by a dual approach consisting of the iRGD-mediated placenta-targeting effect and special particle size-mediated placenta resident effect. The pharmacokinetic study revealed a significant improvement in the in vivo process of tadalafil encapsulated by the iRGD-modified liposomes. In comparison to the tadalafil solution, the peak plasma concentration of iRGD-lipo@Tad was significantly increased, and the area under the curve was increased by about 7.88 times. In the pharmacodynamic study, iRGD-lipo@Tad achieved a continuous and efficient improvement of placental blood perfusion. This was achieved by decreasing the ratio of plasma soluble fms-like tyrosine kinase to placental growth factor and increasing the levels of cyclic guanosine monophosphate and nitric oxide. Consequently, iRGD-lipo@Tad resulted in a significant increase in embryo weight and a reduction in the miscarriage rate of N-Nitro-L-arginine methyl ester-induced IUGR pregnant mice without detectable toxicity. In summary, the nanotechnology-assisted therapy strategy presented here not only overcomes the limitations of tadalafil in the clinical treatment of IUGR but also offers new avenues to address the treatment of other placenta-originated diseases.


Assuntos
Lipossomos , Placenta , Humanos , Feminino , Gravidez , Animais , Camundongos , Lipossomos/metabolismo , Tadalafila/uso terapêutico , Tadalafila/metabolismo , Placenta/metabolismo , Placenta/patologia , Retardo do Crescimento Fetal/tratamento farmacológico , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/patologia , Distribuição Tecidual , Fator de Crescimento Placentário/metabolismo , Perfusão
13.
J Autoimmun ; 144: 103174, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38377868

RESUMO

In many autoimmune diseases, autoantigen-specific Th17 cells play a pivotal role in disease pathogenesis. Th17 cells can transdifferentiate into other T cell subsets in inflammatory conditions, however, there have been no attempts to target Th17 cell plasticity using vaccines. We investigated if autoantigen-specific Th17 cells could be specifically targeted using a therapeutic vaccine approach, where antigen was formulated in all-trans retinoic acid (ATRA)-containing liposomes, permitting co-delivery of antigen and ATRA to the same target cell. Whilst ATRA was previously found to broadly reduce Th17 responses, we found that antigen formulated in ATRA-containing cationic liposomes only inhibited Th17 cells in an antigen-specific manner and not when combined with an irrelevant antigen. Furthermore, this approach shifted existing Th17 cells away from IL-17A expression and transcriptomic analysis of sorted Th17 lineage cells from IL-17 fate reporter mice revealed a shift of antigen-specific Th17 cells to exTh17 cells, expressing functional markers associated with T cell regulation and tolerance. In the experimental autoimmune encephalomyelitis (EAE) mouse model of MS, vaccination with myelin-specific (MOG) antigen in ATRA-containing liposomes reduced Th17 responses and alleviated disease. This highlights the potential of therapeutic vaccination for changing the phenotype of existing Th17 cells in the context of immune mediated diseases.


Assuntos
Encefalomielite Autoimune Experimental , Células Th17 , Camundongos , Animais , Lipossomos/metabolismo , Tretinoína/farmacologia , Tretinoína/metabolismo , Autoantígenos/metabolismo , Adjuvantes Imunológicos , Imunização , Vacinação , Fenótipo , Camundongos Endogâmicos C57BL , Células Th1
14.
Int J Mol Med ; 53(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38390952

RESUMO

Calcium overload, a notable instigator of acute pancreatitis (AP), induces oxidative stress and an inflammatory cascade, subsequently activating both endogenous and exogenous apoptotic pathways. However, there is currently lack of available pharmaceutical interventions to alleviate AP by addressing calcium overload. In the present study, the potential clinical application of liposome nanoparticles (LNs) loaded with 1,2­bis(2­aminophenoxy)ethane­N,N,N',N'­tetraacetic acid tetrakis (acetoxymethyl ester) (BAPTA­AM), a cell­permeant calcium chelator, was investigated as a therapeutic approach for the management of AP. To establish the experimental models in vitro, AR42J cells were exposed to high glucose/sodium oleate (HGO) to induce necrosis, and in vivo, intra­ductal taurocholate (TC) infusion was used to induce AP. The findings of the present study indicated that the use of BAPTA­AM­loaded LN (BLN) effectively and rapidly eliminated excessive Ca2+ and reactive oxygen species, suppressed mononuclear macrophage activation and the release of inflammatory cytokines, and mitigated pancreatic acinar cell apoptosis and necrosis induced by HGO. Furthermore, the systemic administration of BLN demonstrated promising therapeutic potential in the rat model of AP. Notably, BLN significantly enhanced the survival rates of rats subjected to the TC challenge, increasing from 37.5 to 75%. This improvement was attributed to the restoration of pancreatic function, as indicated by improved blood biochemistry indices and alleviation of pancreatic lesions. The potential therapeutic efficacy of BLN in rescuing patients with AP is likely attributed to its capacity to inhibit oxidative stress, prevent premature activation of zymogens and downregulate the expression of TNF­α, IL­6 and cathepsin B. Thus, BLN demonstrated promising value as a novel therapeutic approach for promptly alleviating the burden of intracellular Ca2+ overload in patients with AP.


Assuntos
Ácido Egtázico/análogos & derivados , Pancreatite , Humanos , Ratos , Animais , Pancreatite/metabolismo , Lipossomos/metabolismo , Cálcio/metabolismo , Doença Aguda , Células Acinares/patologia , Necrose/metabolismo
15.
Am J Physiol Lung Cell Mol Physiol ; 326(4): L458-L467, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349117

RESUMO

This study addressed the efficacy of a liposome-encapsulated nine amino acid peptide [peroxiredoxin 6 PLA2 inhibitory peptide-2 (PIP-2)] for the prevention or treatment of acute lung injury (ALI) +/- sepsis. PIP-2 inhibits the PLA2 activity of peroxiredoxin 6 (Prdx6), thereby preventing rac release and activation of NADPH oxidases (NOXes), types 1 and 2. Female Yorkshire pigs were infused intravenously with lipopolysaccharide (LPS) + liposomes (untreated) or LPS + PIP-2 encapsulated in liposomes (treated). Pigs were mechanically ventilated and continuously monitored; they were euthanized after 8 h or earlier if preestablished humane endpoints were reached. Control pigs (mechanical ventilation, no LPS) were essentially unchanged over the 8 h study. LPS administration resulted in systemic inflammation with manifestations of clinical sepsis-like syndrome, decreased lung compliance, and a marked decrease in the arterial Po2 with vascular instability leading to early euthanasia of 50% of untreated animals. PIP-2 treatment significantly reduced the requirement for supportive vasopressors and the manifestations of lung injury so that only 25% of animals required early euthanasia. Bronchoalveolar lavage fluid from PIP-2-treated versus untreated pigs showed markedly lower levels of total protein, cytokines (TNF-α, IL-6, IL-1ß), and myeloperoxidase. Thus, the porcine LPS-induced sepsis-like model was associated with moderate to severe lung pathophysiology compatible with ALI, whereas treatment with PIP-2 markedly decreased lung injury, cardiovascular instability, and early euthanasia. These results indicate that inhibition of reactive oxygen species (ROS) production via NOX1/2 has a beneficial effect in treating pigs with LPS-induced ALI plus or minus a sepsis-like syndrome, suggesting a potential role for PIP-2 in the treatment of ALI and/or sepsis in humans.NEW & NOTEWORTHY Currently available treatments that can alter lung inflammation have failed to significantly alter mortality of acute lung injury (ALI). Peroxiredoxin 6 PLA2 inhibitory peptide-2 (PIP-2) targets the liberation of reactive O2 species (ROS) that is associated with adverse cell signaling events, thereby decreasing the tissue oxidative injury that occurs early in the ALI syndrome. We propose that treatment with PIP-2 may be effective in preventing progression of early disease into its later stages with irreversible lung damage and relatively high mortality.


Assuntos
Lesão Pulmonar Aguda , Sepse , Humanos , Feminino , Animais , Suínos , Lipopolissacarídeos/farmacologia , Proteína A Associada a Surfactante Pulmonar/metabolismo , Peroxirredoxina VI/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Lipossomos/metabolismo , Lipossomos/farmacologia , Lipossomos/uso terapêutico , Pulmão/metabolismo , Lesão Pulmonar Aguda/metabolismo , Peptídeos/farmacologia , Sepse/metabolismo , NADPH Oxidase 1/metabolismo , NADPH Oxidase 1/farmacologia
16.
Nanoscale ; 16(10): 5280-5293, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38369899

RESUMO

Macrophage-driven inflammation is the central player in a range of pathological conditions, comprising autoimmune disorders, various cancers, as well as chronic inflammatory states like rheumatoid arthritis. Therapeutic strategies tailored to specifically target macrophage behavior have acquired substantial interest for their potential to alleviate chronic inflammation effectively. In this study, we introduce a pioneering therapeutic approach utilizing specialized CD44-targeted immunoliposomes carrying bortezomib to address inflammation at the cellular level and the significance of this strategy lies in its precision nature. Bortezomib's inhibition of the proteasome interferes with the finely-tuned mechanism that controls NFκB activation, ultimately leading to a downregulation of the inflammatory response. After performing computational docking demonstrating its strong binding affinity to the proteasome molecule, the resulting nano-construct displayed a hydrodynamic size of 144.26 ± 74.4 nm and a quasi-spherical morphology. Moreover, the nano-construct ensured a minimum shelf-life of 30 days, aiming for targeted delivery with practical longevity. Upon internalization of immunoliposomes, the interaction with CD44 receptors exhibited downstream signaling events. This included the activation of Jun amino-terminal kinases 1/2 (JNK1/2) and the extracellular-signal-regulated kinases (ERK) pathway. JNK1/2 activation may lead to the release of mitochondrial pro-apoptotic factors, triggering the intrinsic apoptotic pathway and activation of caspases, which was confirmed from the level of apoptotic gene and protein expression. The precise targeting and anti-inflammatory action of this therapy against macrophages hold promise for therapeutic interventions in a wide range of inflammatory conditions, offering a novel avenue for precision medicine in the battle against excessive inflammation.


Assuntos
Inflamação , Complexo de Endopeptidases do Proteassoma , Humanos , Bortezomib/farmacologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/farmacologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipossomos/metabolismo , Macrófagos/metabolismo , Receptores de Hialuronatos/metabolismo
17.
Sci Adv ; 10(7): eadj4047, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363847

RESUMO

Cortex-like cytoskeleton, a thin layer of cross-linked cytoplasmic proteins underlying the cell membrane, plays an essential role in modulating membrane behavior and cell surface properties. However, bottom-up construction of functional cortex-like cytoskeleton in artificial cells remains a challenge. Here, we present metal-phenolic networks as artificial cortical cytoskeletons in liposome-based artificial cells. The metal-phenolic cytoskeleton-reinforced artificial cells exhibit long-term stability, enhanced resistance to a variety of harsh environments, tunable permeability, and well-controlled morphologies. We anticipate that our stable artificial cell models will stride forward to practical applications of liposome-based microsystem.


Assuntos
Células Artificiais , Lipossomos/metabolismo , Citoesqueleto/metabolismo , Microtúbulos , Membrana Celular/metabolismo , Metais/metabolismo
18.
Int J Mol Sci ; 25(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38396666

RESUMO

Aquaporins (AQPs), membrane proteins responsible for facilitating water transport, found in plant membrane vesicles (MV), have been related to the functionality and stability of MV. We focused on AQPs obtained from broccoli, as they show potential for biotechnological applications. To gain further insight into the role of AQPs in MV, we describe the heterologous overexpression of two broccoli AQPs (BoPIP1;2 and BoPIP2;2) in Pichia pastoris, resulting in their purification with high yield (0.14 and 0.99 mg per gram cells for BoPIP1;2 and BoPIP2;2). We reconstituted AQPs in liposomes to study their functionality, and the size of proteoliposomes did not change concerning liposomes. BoPIP2;2 facilitated water transport, which was preserved for seven days at 4 °C and at room temperature but not at 37 °C. BoPIP2;2 was incorporated into liposomes to encapsulate a resveratrol extract, resulting in increased entrapment efficiency (EE) compared to conventional liposomes. Molecular docking was utilized to identify binding sites in PIP2s for resveratrol, highlighting the role of aquaporins in the improved EE. Moreover, interactions between plant AQP and human integrin were shown, which may increase internalization by the human target cells. Our results suggest AQP-based alternative encapsulation systems can be used in specifically targeted biotechnological applications.


Assuntos
Aquaporinas , Brassica , Proteolipídeos , Humanos , Lipossomos/metabolismo , Resveratrol/metabolismo , Simulação de Acoplamento Molecular , Aquaporinas/metabolismo , Brassica/genética , Brassica/metabolismo , Água/química
19.
Mol Biol Rep ; 51(1): 355, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38400844

RESUMO

Nanoparticle-based delivery systems have emerged as powerful tools in the field of pest management, offering precise and effective means of delivering double-stranded RNA (dsRNA), a potent agent for pest control through RNA interference (RNAi). This comprehensive review aims to evaluate and compare various types of nanoparticles for their suitability in dsRNA delivery for pest management applications. The review begins by examining the unique properties and advantages of different nanoparticle materials, including clay, chitosan, liposomes, carbon, gold and silica. Each material's ability to protect dsRNA from degradation and its potential for targeted delivery to pests are assessed. Furthermore, this review delves into the surface modification strategies employed to enhance dsRNA delivery efficiency. Functionalization with oligonucleotides, lipids, polymers, proteins and peptides is discussed in detail, highlighting their role in improving stability, cellular uptake, and specificity of dsRNA delivery.This review also provides valuable guidance on choosing the most suitable nanoparticle-based system for delivering dsRNA effectively and sustainably in pest management. Moreover, it identifies existing knowledge gaps and proposes potential research directions aimed at enhancing pest control strategies through the utilization of nanoparticles and dsRNA.


Assuntos
Nanopartículas , RNA de Cadeia Dupla , Animais , Insetos/genética , Interferência de RNA , Lipossomos/metabolismo , Controle de Pragas
20.
Toxins (Basel) ; 16(2)2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38393166

RESUMO

Bacillus thuringiensis Vip3 toxins form a tetrameric structure crucial for their insecticidal activity. Each Vip3Aa monomer comprises five domains. Interaction of the first four α-helices in domain I with the target cellular membrane was proposed to be a key step before pore formation. In this study, four N-terminal α-helix-deleted truncations of Vip3Aa were produced and, it was found that they lost both liposome permeability and insecticidal activity against Spodoptera litura. To further probe the role of domain I in membrane permeation, the full-length domain I and the fragments of N-terminal α-helix-truncated domain I were fused to green fluorescent protein (GFP), respectively. Only the fusion carrying the full-length domain I exhibited permeability against artificial liposomes. In addition, seven Vip3Aa-Cry1Ac fusions were also constructed by combination of α-helices from Vip3Aa domains I and II with the domains II and III of Cry1Ac. Five of the seven combinations were determined to show membrane permeability in artificial liposomes. However, none of the Vip3Aa-Cry1Ac combinations exhibited insecticidal activity due to the significant reduction in proteolytic stability. These results indicated that the N-terminal helix α1 in the Vip3Aa domain I is essential for both insecticidal activity and liposome permeability and that domain I of Vip3Aa preserved a high liposome permeability independently from domains II-V.


Assuntos
Bacillus thuringiensis , Inseticidas , Animais , Bacillus thuringiensis/metabolismo , Lipossomos/metabolismo , Conformação Proteica em alfa-Hélice , Inseticidas/química , Toxinas de Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/metabolismo , Larva/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo
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