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1.
Commun Biol ; 7(1): 458, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622242

RESUMO

Differentiation of adipose progenitor cells into mature adipocytes entails a dramatic reorganization of the cellular architecture to accommodate lipid storage into cytoplasmic lipid droplets. Lipid droplets occupy most of the adipocyte volume, compressing the nucleus beneath the plasma membrane. How this cellular remodeling affects sub-nuclear structure, including size and number of nucleoli, remains unclear. We describe the morphological remodeling of the nucleus and the nucleolus during in vitro adipogenic differentiation of primary human adipose stem cells. We find that cell cycle arrest elicits a remodeling of nucleolar structure which correlates with a decrease in protein synthesis. Strikingly, triggering cytoskeletal rearrangements mimics the nucleolar remodeling observed during adipogenesis. Our results point to nucleolar remodeling as an active, mechano-regulated mechanism during adipogenic differentiation and demonstrate a key role of the actin cytoskeleton in defining nuclear and nucleolar architecture in differentiating human adipose stem cells.


Assuntos
Adipogenia , Citoesqueleto , Humanos , Células Cultivadas , Citoesqueleto/metabolismo , Adipócitos/metabolismo , Gotículas Lipídicas/metabolismo
2.
Nutrients ; 16(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38612988

RESUMO

The goblet cells of the gastrointestinal tract (GIT) produce glycoproteins called mucins that form a protective barrier from digestive contents and external stimuli. Recent evidence suggests that the milk fat globule membrane (MFGM) and its milk phospholipid component (MPL) can benefit the GIT through improving barrier function. Our objective was to compare the effects of two digested MFGM ingredients with or without dextran sodium sulfate (DSS)-induced barrier stress on mucin proteins. Co-cultured Caco-2/HT29-MTX intestinal cells were treated with in vitro digests of 2%, 5%, and 10% (w/v) MFGM or MPL alone for 6 h or followed by challenge with 2.5% DSS (6 h). Transepithelial electrical resistance and fluorescein isothiocyanate (FITC)-dextran (FD4) permeability measurements were used to measure changes in barrier integrity. Mucin characterization was performed using a combination of slot blotting techniques for secreted (MUC5AC, MUC2) and transmembrane (MUC3A, MUC1) mucins, scanning electron microscopy (SEM), and periodic acid Schiff (PAS)/Alcian blue staining. Digested MFGM and MPL prevented a DSS-induced reduction in secreted mucins, which corresponded to the prevention of DSS-induced increases in FD4 permeability. SEM and PAS/Alcian blue staining showed similar visual trends for secreted mucin production. A predictive bioinformatic approach was also used to identify potential KEGG pathways involved in MFGM-mediated mucosal maintenance under colitis conditions. This preliminary in silico evidence, combined with our in vitro findings, suggests the role of MFGM in inducing repair and maintenance of the mucosal barrier.


Assuntos
Dextranos , Fluoresceína-5-Isotiocianato/análogos & derivados , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Humanos , Células CACO-2 , Azul Alciano , Glicoproteínas/farmacologia , Células Epiteliais , Mucinas
3.
Nat Commun ; 15(1): 3213, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615060

RESUMO

Oxidative stress-induced lipid accumulation is mediated by lipid droplets (LDs) homeostasis, which sequester vulnerable unsaturated triglycerides into LDs to prevent further peroxidation. Here we identify the upregulation of lipopolysaccharide-binding protein (LBP) and its trafficking through LDs as a mechanism for modulating LD homeostasis in response to oxidative stress. Our results suggest that LBP induces lipid accumulation by controlling lipid-redox homeostasis through its lipid-capture activity, sorting unsaturated triglycerides into LDs. N-acetyl-L-cysteine treatment reduces LBP-mediated triglycerides accumulation by phospholipid/triglycerides competition and Peroxiredoxin 4, a redox state sensor of LBP that regulates the shuttle of LBP from LDs. Furthermore, chronic stress upregulates LBP expression, leading to insulin resistance and obesity. Our findings contribute to the understanding of the role of LBP in regulating LD homeostasis and against cellular peroxidative injury. These insights could inform the development of redox-based therapies for alleviating oxidative stress-induced metabolic dysfunction.


Assuntos
Proteínas de Fase Aguda , Proteínas de Transporte , Gotículas Lipídicas , Lipopolissacarídeos , Glicoproteínas de Membrana , Homeostase , Estresse Oxidativo , Triglicerídeos
4.
Cell Death Dis ; 15(4): 240, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561354

RESUMO

Abnormal lipid metabolism and lipid accumulation are characteristic hallmarks of renal cell carcinoma (RCC). While there is prior evidence closely linking such lipid accumulation within RCC cells and consequent tumorigenesis, the mechanisms underlying this process remain incompletely understood. In this study, a series of bioinformatics analyses were initially performed by screening RCC databases and gene sets, ultimately leading to the identification of TRIB3 as an oncogene that functions as a central regulator of lipid metabolism. TRIB3 overexpression was observed in both RCC patient tumor tissues and cell lines, and this upregulation was correlated with a worse RCC patient prognosis. When TRIB3 was knocked down, this resulted in a reduction in lipid accumulation and the consequent induction of endoplasmic reticulum (ER) stress-related apoptotic cell death. At the molecular level, interactions between TRIB3 and PLIN2 were found to abrogate TEB4-mediated PLIN2 ubiquitination and consequent degradation, thus maintaining higher PLIN2 expression levels. This simultaneously helps facilitate the accumulation of lipids while preserving ER homeostasis, thus driving accelerated RCC tumor progression. This TRIB3-PLIN2 axis thus represents a promising new target for efforts to treat RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Humanos , Carcinoma de Células Renais/metabolismo , Gotículas Lipídicas/metabolismo , Estresse do Retículo Endoplasmático/genética , Neoplasias Renais/metabolismo , Lipídeos , Proteínas Repressoras/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Perilipina-2/genética , Perilipina-2/metabolismo
5.
Opt Express ; 32(7): 12462-12475, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571068

RESUMO

Quantitative phase contrast microscopy (QPCM) can realize high-quality imaging of sub-organelles inside live cells without fluorescence labeling, yet it requires at least three phase-shifted intensity images. Herein, we combine a novel convolutional neural network with QPCM to quantitatively obtain the phase distribution of a sample by only using two phase-shifted intensity images. Furthermore, we upgraded the QPCM setup by using a phase-type spatial light modulator (SLM) to record two phase-shifted intensity images in one shot, allowing for real-time quantitative phase imaging of moving samples or dynamic processes. The proposed technique was demonstrated by imaging the fine structures and fast dynamic behaviors of sub-organelles inside live COS7 cells and 3T3 cells, including mitochondria and lipid droplets, with a lateral spatial resolution of 245 nm and an imaging speed of 250 frames per second (FPS). We imagine that the proposed technique can provide an effective way for the high spatiotemporal resolution, high contrast, and label-free dynamic imaging of living cells.


Assuntos
Aprendizado Profundo , 60704 , Animais , Camundongos , Mitocôndrias , Gotículas Lipídicas
6.
J Physiol ; 602(5): 891-912, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38429930

RESUMO

Skeletal muscle cellular development requires the integrated assembly of mitochondria and other organelles adjacent to the sarcomere in support of muscle contractile performance. However, it remains unclear how interactions among organelles and with the sarcomere relates to the development of muscle cell function. Here, we combine 3D volume electron microscopy, proteomic analyses, and live cell functional imaging to investigate the postnatal reorganization of mitochondria-organelle interactions in skeletal muscle. We show that while mitochondrial networks are disorganized and loosely associated with the contractile apparatus at birth, contact sites among mitochondria, lipid droplets and the sarcoplasmic reticulum are highly abundant in neonatal muscles. The maturation process is characterized by a transition to highly organized mitochondrial networks wrapped tightly around the muscle sarcomere but also to less frequent interactions with both lipid droplets and the sarcoplasmic reticulum. Concomitantly, expression of proteins involved in mitochondria-organelle membrane contact sites decreases during postnatal development in tandem with a decrease in abundance of proteins associated with sarcomere assembly despite an overall increase in contractile protein abundance. Functionally, parallel measures of mitochondrial membrane potential, NADH redox status, and NADH flux within intact cells revealed that mitochondria in adult skeletal muscle fibres maintain a more activated electron transport chain compared with neonatal muscle mitochondria. These data demonstrate a developmental redesign reflecting a shift from muscle cell assembly and frequent inter-organelle communication toward a muscle fibre with mitochondrial structure, interactions, composition and function specialized to support contractile function. KEY POINTS: Mitochondrial network organization is remodelled during skeletal muscle postnatal development. The mitochondrial outer membrane is in frequent contact with other organelles at birth and transitions to more close associations with the contractile apparatus in mature muscles. Mitochondrial energy metabolism becomes more activated during postnatal development. Understanding the developmental redesign process within skeletal muscle cells may help pinpoint specific areas of deficit in muscles with developmental disorders.


Assuntos
NAD , Proteômica , Humanos , Adulto , Recém-Nascido , NAD/metabolismo , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Mitocôndrias Musculares/metabolismo , Gotículas Lipídicas/metabolismo
7.
Anal Chim Acta ; 1299: 342422, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38499425

RESUMO

BACKGROUND: Ferroptosis, as a novel form of cell death, is becoming one of the hot topics in cancer treatment research. It differs from necrosis and autophagy in that it involves the accumulation of lipid peroxides and is triggered by iron dependency. Recent studies have suggested that this mechanism may alter the viscosity or structure of lipid droplets (LDs). The relationship between LDs viscosity and ferroptosis remains an active area of research with limited reports at present. Additionally, there is a lack of effective anticancer drugs targeting the ferroptosis pathway to promote ferroptosis in tumour cells. Therefore, the development of tools to detect viscosity changes during ferroptosis and targeted therapeutic strategies is of great significance. RESULTS: By coupling 1,3-indandione with naphthalimide, including decamethylamine as a LDs recognition group, we designed and synthesized an environmental fluorescent probe that induces intramolecular charge transfer (TICT) effects. Notably, the diffusion and transport of intracellular substances may be affected in highly viscous environments. Under such conditions, intracellular iron ions may accumulate, leading to peroxide production and cellular damage, which can trigger ferroptosis. Therefore, WD-1 achieved excellent in situ bioimaging of LDs targeting and its viscosity during ferroptosis in HeLa cells and zebrafish. Furthermore, it was observed that WD-1 effectively differentiated between malignant and normal cells during this process, highlighting its potential significance in distinguishing cellular states. In addition, we used the antitumour drug paclitaxel to study ferroptosis in cancer cells. These findings not only provide an excellent tool for the development of the ferroptosis response, but also are crucial for understanding the biological properties of LDs during the ferroptosis response. SIGNIFICANCE AND NOVELTY: Based on a powerful tool of fluorescent probe with in vivo bioimaging, we developed WD-1 to track the impact of paclitaxel on the process of ferroptosis in living cells. Therefore, we preliminarily believe that paclitaxel may affect the occurrence of ferroptosis and control apoptosis in cancer cells. These findings not only serve as an exceptional tool for advancing our understanding of the ferroptosis response, but furthermore play a vital role in comprehending the biological characteristics of LDs in relation to ferroptosis.


Assuntos
Ferroptose , Gotículas Lipídicas , Humanos , Animais , Corantes Fluorescentes , Células HeLa , Viscosidade , Peixe-Zebra , Ferro , Paclitaxel/farmacologia
8.
J Mater Chem B ; 12(12): 3022-3030, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38426244

RESUMO

Lipid droplets (LDs) are cytoplasmic lipid-rich organelles with important roles in lipid storage and metabolism, cell signaling and membrane biosynthesis. Additionally, multiple diseases, such as obesity, fatty liver, cardiovascular diseases and cancer, are related to the metabolic disorders of LDs. In various cancer cells, LD accumulation is associated with resistance to cell death, reduced effectiveness of chemotherapeutic drugs, and increased proliferation and aggressiveness. In this work, we present a new viscosity-sensitive, green-emitting BODIPY probe capable of distinguishing between ordered and disordered lipid phases and selectively internalising into LDs of live cells. Through the use of fluorescence lifetime imaging microscopy (FLIM), we demonstrate that LDs in live cancer (A549) and non-cancer (HEK 293T) cells have vastly different microviscosities. Additionally, we quantify the microviscosity changes in LDs under the influence of DNA-damaging chemotherapy drugs doxorubicin and etoposide. Finally, we show that doxorubicin and etoposide have different effects on the microviscosities of LDs in chemotherapy-resistant A549 cancer cells.


Assuntos
Compostos de Boro , Gotículas Lipídicas , Neoplasias , Gotículas Lipídicas/metabolismo , Corantes Fluorescentes/farmacologia , Corantes Fluorescentes/metabolismo , Etoposídeo/metabolismo , Lipídeos , Doxorrubicina/farmacologia , Doxorrubicina/metabolismo , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
9.
J Agric Food Chem ; 72(11): 6040-6052, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38454851

RESUMO

One type of large and intricate post-translational modification of milk proteins that has significant biological implications is phosphorylation. The characterization of phosphoproteins found in the bovine milk fat globule membrane (MFGM) is still mostly unknown. Here, label-free phosphoproteomics was used to identify 94 phosphorylation sites from 54 MFGM phosphoproteins in bovine colostrum (BC) and 136 phosphorylation sites from 91 MFGM phosphoproteins in bovine mature milk (BM). αs1-Casein and ß-casein were the most phosphorylated proteins in bovine colostrum. In bovine mature milk, perilipin-2 was the protein with the greatest number of phosphorylation sites. The results show that bovine colostrum MFGM phosphoproteins were mainly involved in immune function, whereas bovine mature MFGM phosphoproteins were mainly involved in metabolic function. Plasminogen and osteopontin were the most strongly interacting proteins in colostrum, whereas perilipin-2 was the most strongly interacting protein in bovine mature milk. This work demonstrates the unique alterations in the phosphorylation manner of the bovine MFGM protein during lactation and further expands our knowledge of the site characteristics of bovine MFGM phosphoproteins. This result confirms the value of MFGM as a reference ingredient for infant formula during different stages.


Assuntos
Colostro , Glicoproteínas , Leite , Feminino , Gravidez , Lactente , Humanos , Animais , Colostro/metabolismo , Perilipina-2/metabolismo , Leite/metabolismo , Glicolipídeos/metabolismo , Gotículas Lipídicas/metabolismo , Proteínas do Leite/metabolismo , Caseínas/metabolismo
10.
Colloids Surf B Biointerfaces ; 236: 113819, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428208

RESUMO

Organisms have evolved intracellular micron-sized lipid droplets to carry and protect lipids and hydrophobic minor compounds in the hydrophilic environment of cells. These droplets can be utilized as carriers of hydrophobic therapeutics by taking advantage of their biological functions. Here, we focus on the potential of plant-derived lipid droplets, known as oleosomes, as carriers for hydrophobic therapeutics, such as curcumin. By spectroscopy and confocal microscopy, we demonstrate that the oleosome membrane is permeable to hydrophobic curcumin molecules. Fluorescence recovery after photobleaching shows rapid curcumin diffusion towards oleosomes, with a diffusion time in the range of seconds. Following this, quenching probes and dilatational rheology reveal that part of the loaded curcumin molecules can accumulate at the oleosome interface, and the rest settle in the inner core. Our findings shed light on the loading mechanism of the plant-derived lipid droplets and underscore the significance of molecular localization for understanding the mechanism. This work not only enhances the understanding of the loading process but also shows potential for oleosomes use as lipid carriers.


Assuntos
Curcumina , Gotículas Lipídicas , Fluorescência
11.
Curr Opin Cell Biol ; 87: 102342, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428224

RESUMO

Lipid droplets (LDs), once considered mere storage depots for lipids, have gained recognition for their intricate roles in cellular processes, including metabolism, membrane trafficking, and disease states like obesity and cancer. This review explores label-free imaging techniques' applications in LD research. We discuss holotomography and vibrational spectroscopic microscopy, emphasizing their potential for studying LDs without molecular labels, and we highlight the growing integration of artificial intelligence. Clinical applications in disease diagnosis and therapy are also considered.


Assuntos
Inteligência Artificial , Gotículas Lipídicas , Gotículas Lipídicas/metabolismo , Microscopia , Metabolismo dos Lipídeos
12.
Nat Cell Biol ; 26(3): 331-345, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38454048

RESUMO

Lipid droplets are dynamic organelles that store neutral lipids, serve the metabolic needs of cells, and sequester lipids to prevent lipotoxicity and membrane damage. Here we review the current understanding of the mechanisms of lipid droplet biogenesis and turnover, the transfer of lipids and metabolites at membrane contact sites, and the role of lipid droplets in regulating fatty acid flux in lipotoxicity and cell death.


Assuntos
Gotículas Lipídicas , Metabolismo dos Lipídeos , Gotículas Lipídicas/metabolismo , Homeostase , Ácidos Graxos/metabolismo
13.
Anal Chim Acta ; 1297: 342330, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38438225

RESUMO

Cellular micro-environment analysis via fluorescence probe has become a powerful method to explore the early-stage cancer diagnosis and pathophysiological process of relevant diseases. The polarity change of intracellular lipid droplets (LDs) is closely linked with disorders or diseases, which result in various physiological and pathological processes. However, the efficient design strategy for lipid droplet polarity probes with high sensitivity is lacking. To overcome this difficulty, two kinds of LDs-targeting and polarity-sensitive fluorescent probes containing carbazole and siloxane groups were rationally designed and synthesized. With the carbazole-based rotor and bridge-like siloxanes, two probes (P1 and P2) behave high sensitivity to polarity changes and show different fluorescent intensity in normal and cancer cells. Notably, polysiloxanes groups promoted the response sensitivity of the probes dramatically for the polymeric microenvironment. In addition, due to the polarity changes of LDs in cancer cells, the distinct fluorescent intensities in different channels of laser scanning confocal microscope were observed between NHA cell and U87 cells. This work could offer an opportunity to monitor the dynamic behaviors of LDs and further provide a powerful tool to be potentially applied in the early-stage diagnosis of cancer.


Assuntos
Gotículas Lipídicas , Neoplasias , Polímeros , Siloxanas , Carbazóis , Corantes Fluorescentes , Neoplasias/diagnóstico por imagem
14.
World J Gastroenterol ; 30(7): 728-741, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515944

RESUMO

BACKGROUND: Liver injury is common in severe acute pancreatitis (SAP). Excessive autophagy often leads to an imbalance of homeostasis in hepatocytes, which induces lipid peroxidation and mitochondrial iron deposition and ultimately leads to ferroptosis. Our previous study found that milk fat globule epidermal growth factor 8 (MFG-E8) alleviates acinar cell damage during SAP via binding to αvß3/5 integrins. MFG-E8 also seems to mitigate pancreatic fibrosis via inhibiting chaperone-mediated autophagy. AIM: To speculate whether MFG-E8 could also alleviate SAP induced liver injury by restoring the abnormal autophagy flux. METHODS: SAP was induced in mice by 2 hly intraperitoneal injections of 4.0 g/kg L-arginine or 7 hly injections of 50 µg/kg cerulein plus lipopolysaccharide. mfge8-knockout mice were used to study the effect of MFG-E8 deficiency on SAP-induced liver injury. Cilengitide, a specific αvß3/5 integrin inhibitor, was used to investigate the possible mechanism of MFG-E8. RESULTS: The results showed that MFG-E8 deficiency aggravated SAP-induced liver injury in mice, enhanced autophagy flux in hepatocyte, and worsened the degree of ferroptosis. Exogenous MFG-E8 reduced SAP-induced liver injury in a dose-dependent manner. Mechanistically, MFG-E8 mitigated excessive autophagy and inhibited ferroptosis in liver cells. Cilengitide abolished MFG-E8's beneficial effects in SAP-induced liver injury. CONCLUSION: MFG-E8 acts as an endogenous protective mediator in SAP-induced liver injury. MFG-E8 alleviates the excessive autophagy and inhibits ferroptosis in hepatocytes by binding to integrin αVß3/5.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Ferroptose , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Pancreatite , Camundongos , Animais , Fator VIII , Pancreatite/induzido quimicamente , Pancreatite/complicações , Doença Aguda , Hepatócitos/metabolismo , Autofagia , Família de Proteínas EGF , Proteínas do Leite/metabolismo , Proteínas do Leite/farmacologia
15.
Genomics ; 116(2): 110817, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38431031

RESUMO

Perilipin-2 (PLIN2) can anchor to lipid droplets (LDs) and play a crucial role in regulating nascent LDs formation. Bimolecular fluorescence complementation (BiFC) and flow cytometry were examined to verify the PLIN2-CGI-58 interaction efficiency in bovine adipocytes. GST-Pulldown assay was used to detect the key site arginine315 function in PLIN2-CGI-58 interaction. Experiments were also examined to research these mutations function of PLIN2 in LDs formation during adipocytes differentiation, LDs were measured after staining by BODIPY, lipogenesis-related genes were also detected. Results showed that Leucine (L371A, L311A) and glycine (G369A, G376A) mutations reduced interaction efficiencies. Serine (S367A) mutations enhanced the interaction efficiency. Arginine (R315A) mutations resulted in loss of fluorescence in the cytoplasm and disrupted the interaction with CGI-58, as verified by pulldown assay. R315W mutations resulted in a significant increase in the number of LDs compared with wild-type (WT) PLIN2 or the R315A mutations. Lipogenesis-related genes were either up- or downregulated when mutated PLIN2 interacted with CGI-58. Arginine315 in PLIN2 is required for the PLIN2-CGI-58 interface and could regulate nascent LD formation and lipogenesis. This study is the first to study amino acids on the PLIN2 interface during interaction with CGI-58 in bovine and highlight the role played by PLIN2 in the regulation of bovine adipocyte lipogenesis.


Assuntos
Arginina , Gotículas Lipídicas , Animais , Bovinos , Perilipina-2/genética , Perilipina-2/química , Perilipina-2/metabolismo , Arginina/genética , Arginina/metabolismo , Gotículas Lipídicas/metabolismo , Mutação , Adipócitos/metabolismo , Metabolismo dos Lipídeos
16.
J Virol ; 98(4): e0017124, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38488361

RESUMO

The global impact of emerging viral infections emphasizes the urgent need for effective broad-spectrum antivirals. The cellular organelle, lipid droplet (LD), is utilized by many types of viruses for replication, but its reduction does not affect cell survival. Therefore, LD is a potential target for developing broad-spectrum antivirals. In this study, we found that 2-bromopalmitate (2 BP), a previously defined palmitoylation inhibitor, depletes LD across all studied cell lines and exerts remarkable antiviral effects on different coronaviruses. We comprehensively utilized 2 BP, alongside other palmitoylation inhibitors such as cerulenin and 2-fluoro palmitic acid (2-FPA), as well as the enhancer palmostatin B and evaluated their impact on LD and the replication of human coronaviruses (hCoV-229E, hCoV-Oc43) and murine hepatitis virus (MHV-A59) at non-cytotoxic concentrations. While cerulenin and 2-FPA exhibited moderate inhibition of viral replication, 2 BP exhibited a much stronger suppressive effect on MHV-A59 replication, although they share similar inhibitory effects on palmitoylation. As expected, palmostatin B significantly enhanced viral replication, it failed to rescue the inhibitory effects of 2 BP, whereas it effectively counteracted the effects of cerulenin and 2-FPA. This suggests that the mechanism that 2 BP used to inhibit viral replication is beyond palmitoylation inhibition. Further investigations unveil that 2 BP uniquely depletes LDs, a phenomenon not exhibited by 2-FPA and cerulenin. Importantly, the depletion of LDs was closely associated with the inhibition of viral replication because the addition of oleic acid to 2 BP significantly rescued LD depletion and its inhibitory effects on MHV-A59. Our findings indicate that the inhibitory effects of 2 BP on viral replication primarily stem from LD disruption rather than palmitoylation inhibition. Intriguingly, fatty acid (FA) assays demonstrated that 2 BP reduces the FA level in mitochondria while concurrently increasing FA levels in the cytoplasm. These results highlight the crucial role of LDs in viral replication and uncover a novel biological activity of 2 BP. These insights contribute to the development of broad-spectrum antiviral strategies. IMPORTANCE: In our study, we conducted a comparative investigation into the antiviral effects of palmitoylation inhibitors including 2-bromopalmitate (2-BP), 2-fluoro palmitic acid (2-FPA), and cerulenin. Surprisingly, we discovered that 2-BP has superior inhibitory effects on viral replication compared to 2-FPA and cerulenin. However, their inhibitory effects on palmitoylation were the same. Intrigued by this finding, we delved deeper into the underlying mechanism of 2-BP's potent antiviral activity, and we unveiled a novel biological activity of 2-BP: depletion of lipid droplets (LDs). Importantly, we also highlighted the crucial role of LDs in viral replication. Our insights shed new light on the antiviral mechanism of LD depletion paving the way for the development of broad-spectrum antiviral strategies by targeting LDs.


Assuntos
Coronavirus , Gotículas Lipídicas , Palmitatos , Propiolactona/análogos & derivados , Camundongos , Animais , Humanos , Gotículas Lipídicas/metabolismo , Ácido Palmítico/farmacologia , Ácido Palmítico/metabolismo , Cerulenina/metabolismo , Cerulenina/farmacologia , Replicação Viral , Antivirais/farmacologia , Antivirais/metabolismo
17.
Food Chem ; 447: 139008, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38513488

RESUMO

We hypothesized that the addition of milk fat globule membranes (MFGMs) to infant formula would improve its lipolysis, making it more similar to human milk (HM) and superior to commercial infant formula (CIF) in fat digestion. Therefore, we prepared two model infant formulas (MIFs) by adding MFGMs to dairy ingredients in different ways and compared their fat digestion behavior with those of HM and CIF. MFGMs were added alone (MIF1) and with other milk-based materials (MIF2) before homogenization. The addition of MFGMs reduced the flocculation of lipids and proteins in the gastric phase and promoted lipolysis in the intestine phase. The amount of free fatty acids released followed the order of HM > MIF1 > CIF ≥ MIF2. After digestion, the number of different glyceride species between each sample and HM reached 64 (MIF1), 73 (MIF2), 67 (CIF1), and 72 (CIF2). In conclusion, the fat digestion of MIF1 had the highest similarity with HM.


Assuntos
Digestão , Glicoproteínas , Gotículas Lipídicas , Lipidômica , Lactente , Humanos , Glicolipídeos , Leite Humano , Fórmulas Infantis
18.
Anal Chem ; 96(14): 5615-5624, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38544396

RESUMO

Abnormal lipid droplets (LDs) are known to be intimately bound with the occurrence and development of cancer, allowing LDs to be critical biomarkers for cancers. Aggregation-induced emission luminogens (AIEgens), with efficient reactive oxygen species (ROS) production performance, are prime photosensitizers (PSs) for photodynamic therapy (PDT) with imaging. Therefore, the development of dual-functional fluorescent probes with aggregation-induced emission (AIE) characteristics that enable both simultaneous LD monitoring and imaging-guided PDT is essential for concurrent cancer diagnosis and treatment. Herein, we reported the development of a novel LD-targeting fluorescent probe (TDTI) with AIE performance, which was expected to realize the integration of cancer diagnosis through LD visualization and cancer treatment via PDT. We demonstrated that TDTI, with typical AIE characteristics and excellent photostability, could target LDs with high specificity, which enables the dynamic tracking of LDs in living cells, specific imaging of LDs in zebrafish, and the differentiation of cancer cells from normal cells for cancer diagnosis. Meanwhile, TDTI exhibited fast ROS generation ability (achieving equilibrium within 60 s) under white light irradiation (10 mW/cm2). The cell apoptosis assay revealed that TDTI effectively induced growth inhibition and apoptosis of HeLa cells. Further, the results of PDT in vivo indicated that TDTI had a good antitumor effect on the tumor-bearing mice model. Collectively, these results highlight the potential utility of the dual-functional fluorescent probe TDTI in the integrated diagnosis and treatment of cancer.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Animais , Camundongos , Células HeLa , Corantes Fluorescentes , Gotículas Lipídicas/metabolismo , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
19.
Int J Biol Macromol ; 264(Pt 1): 130369, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428775

RESUMO

This research aimed to extract oleosome from the Bene kernel as a carrier of beta-carotene (3, 5, and 10 % w/w) and then use oleosomes in the Quince seed gum (QSG) electrosprayed nanoparticles for the sustained release of beta-carotene in food simulant. Oleosomes loaded with 5 % w/w beta-carotene had the highest encapsulation efficiency (94.53 % ± 1.23 %) and were used at 1, 3, and 5 % w/w in the QSG electrosprayed nanoparticles. Electrospray feed solutions containing 5 % oleosomes loaded with beta-carotene had the highest zeta potential (-34.45 ± 0.58 mV) and the lowest surface tension (23.47 ± 1.10 mN/m). FESEM images showed that with the increase of oleosomes up to 3 % w/w, the average size of the electrosprayed particles decreases. The Fourier transform infrared (FTIR) test proved the presence of protein in the oleosomes and their successful extraction from Bene seeds. Differential scanning calorimetry (DSC) and FTIR proved the successful entrapment of beta-carotene in the oleosomes structure and the successful placement of oleosomes containing beta-carotene in the electrosprayed nanoparticles. The predominant driving force involving the release of beta-carotene from the designed structures in food simulants was the Fickian release mechanism. The Peleg model was introduced as the best model describing the beta-carotene release.


Assuntos
Rosaceae , beta Caroteno , beta Caroteno/química , Gotículas Lipídicas , Sementes/química , Coloides
20.
Int J Biol Macromol ; 264(Pt 1): 130595, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437939

RESUMO

The digestive instability of anthocyanins (ACNs) limits their application in food nutrition, especially precision nutrition. Blueberry ACNs-loaded nanoparticles (Lipo/GA-ACNs NPs) were prepared using gum arabic (GA) as the delivery carrier and liposomal vesicles (Lipo) prepared from soy lecithin as the targeting scaffold. The average particle size of the NPs was 99.4 nm, and the polydispersion index (PDI) was 0.46. The results showed that the presence of the Lipo-GA matrix enhanced the NPs' in vitro stability and antioxidant activity. In addition, the in vitro biocompatibility, uptake ability, lipid-lowering activity, and free-radical scavenging ability were improved to a certain extent. In a high-fat diet (HFD)-induced obese mouse model, oral administration of ACNs-LNP (LNP, liver-targeted nanoparticle) showed better effects on body weight, liver injury, and lipid droplet accumulation in the liver than ACNs. In addition, ACNs-LNP also played a role in regulating HFD-induced gut microbiota imbalance. These results provide a promising ACNs delivery strategy with the potential to be developed into a functional food that targets the liver to prevent fatty liver.


Assuntos
Mirtilos Azuis (Planta) , Microbioma Gastrointestinal , Nanopartículas , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Antocianinas/farmacologia , Camundongos Obesos , Lecitinas , Goma Arábica/farmacologia , Gotículas Lipídicas , Camundongos Endogâmicos C57BL
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