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1.
BMJ Open ; 14(6): e083399, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951000

RESUMO

INTRODUCTION: Milk fat globule membrane (MFGM) is a complex lipid-protein structure in mammalian milk and human milk that is largely absent from breastmilk substitutes. The objective of this trial is to investigate whether providing infant formula enriched with MFGM versus standard infant formula improves cognitive development at 12 months of age in exclusively formula-fed full-term infants. METHODS AND ANALYSIS: This is a randomised, controlled, clinician-blinded, researcher-blinded and participant-blinded trial of two parallel formula-fed groups and a breastfed reference group that were recruited in the suburban Adelaide (Australia) community by a single study centre (a medical research institute). Healthy, exclusively formula-fed, singleton, term-born infants under 8 weeks of age were randomised to either an MFGM-supplemented formula (intervention) or standard infant formula (control) from enrolment until 12 months of age. The reference group was not provided with formula. The primary outcome is the Cognitive Scale of the Bayley Scales of Infant Development, Fourth Edition (Bayley-IV) at 12 months. Secondary outcomes are the Bayley-IV Cognitive Scale at 24 months, other Bayley-IV domains (language, motor, emotional and behavioural development) at 12 and 24 months of age, infant attention at 4 and 9 months of age, parent-rated language at 12 and 24 months of age, parent-rated development at 6 and 18 months of age as well as growth, tolerance and safety of the study formula. To ensure at least 80% power to detect a 5-point difference in the mean Bayley-IV cognitive score, >200 infants were recruited in each group. ETHICS AND DISSEMINATION: The Women's and Children Health Network Human Research Ethics Committee reviewed and approved the study (HREC/19/WCHN/140). Caregivers gave written informed consent prior to enrolling in the trial. Findings of this study will be disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: ACTRN12620000552987; Australian and New Zealand Clinical Trial Registry: anzctr.org.au.


Assuntos
Desenvolvimento Infantil , Cognição , Glicolipídeos , Glicoproteínas , Fórmulas Infantis , Gotículas Lipídicas , Humanos , Glicolipídeos/administração & dosagem , Fórmulas Infantis/química , Glicoproteínas/administração & dosagem , Cognição/efeitos dos fármacos , Lactente , Feminino , Recém-Nascido , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Suplementos Nutricionais , Aleitamento Materno , Leite Humano/química
2.
BMC Genomics ; 25(1): 653, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38956471

RESUMO

BACKGROUND: Oil bodies or lipid droplets (LDs) in the cytosol are the subcellular storage compartments of seeds and the sites of lipid metabolism providing energy to the germinating seeds. Major LD-associated proteins are lipoxygenases, phospholipaseD, oleosins, TAG-lipases, steroleosins, caleosins and SEIPINs; involved in facilitating germination and enhancing peroxidation resulting in off-flavours. However, how natural selection is balancing contradictory processes in lipid-rich seeds remains evasive. The present study was aimed at the prediction of selection signatures among orthologous clades in major oilseeds and the correlation of selection effect with gene expression. RESULTS: The LD-associated genes from the major oil-bearing crops were analyzed to predict natural selection signatures in phylogenetically close-knit ortholog clusters to understand adaptive evolution. Positive selection was the major force driving the evolution and diversification of orthologs in a lineage-specific manner. Significant positive selection effects were found in 94 genes particularly in oleosin and TAG-lipases, purifying with excess of non-synonymous substitution in 44 genes while 35 genes were neutral to selection effects. No significant selection impact was noticed in Brassicaceae as against LOX genes of oil palm. A heavy load of deleterious mutations affecting selection signatures was detected in T-lineage oleosins and LOX genes of Arachis hypogaea. The T-lineage oleosin genes were involved in mainly anther, tapetum and anther wall morphogenesis. In Ricinus communis and Sesamum indicum > 85% of PLD genes were under selection whereas selection pressures were low in Brassica juncea and Helianthus annuus. Steroleosin, caleosin and SEIPINs with large roles in lipid droplet organization expressed mostly in seeds and were under considerable positive selection pressures. Expression divergence was evident among paralogs and homeologs with one gene attaining functional superiority compared to the other. The LOX gene Glyma.13g347500 associated with off-flavor was not expressed during germination, rather its paralog Glyma.13g347600 showed expression in Glycine max. PLD-α genes were expressed on all the tissues except the seed,δ genes in seed and meristem while ß and γ genes expressed in the leaf. CONCLUSIONS: The genes involved in seed germination and lipid metabolism were under strong positive selection, although species differences were discernable. The present study identifies suitable candidate genes enhancing seed oil content and germination wherein directional selection can become more fruitful.


Assuntos
Produtos Agrícolas , Evolução Molecular , Gotículas Lipídicas , Seleção Genética , Gotículas Lipídicas/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Óleos de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo , Sementes/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas
3.
PLoS One ; 19(7): e0306479, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38959226

RESUMO

The histomorphological features of normal kidneys in cats and dogs have been revealed despite the high susceptibility of cats to tubulointerstitial damage. Herein, the histological characteristics of the two species were compared. Cytoplasmic lipid droplets (LDs) were abundant in the proximal convoluted tubules (PCTs) of cats aged 23-27 months but scarce in dogs aged 24-27 months. LDs were rarely observed in the distal tubules (DTs) and collecting ducts (CDs) of either species, as visualized by the expression of Tamm-Horsfall protein 1, calbindin-D28K, and aquaporin 2. The occupational area ratio of proximal tubules (PTs) in the renal cortex was higher, but that of DTs or CDs was significantly lower in adult cats than in dogs. Single PT epithelial cells were larger, but PCT, DT, and CD lumens were significantly narrower in adult cats than in dogs. Unlike adults, young cats at 6 months exhibited significantly abundant cytoplasmic LDs in proximal straight tubules, indicating lipid metabolism-related development. Histochemistry of the 21 lectins also revealed variations in glycosylation across different renal tubules and CDs in both species. Sodium-glucose cotransporter 2 was expressed only in PTs, excluding the proximal straight tubules with few LDs in adult cats or the PCTs of young cats and adult dogs. These findings are crucial for understanding species-specific characteristics of renal histomorphology and pathogenesis.


Assuntos
Túbulos Renais Coletores , Especificidade da Espécie , Animais , Cães , Gatos , Túbulos Renais Coletores/metabolismo , Túbulos Renais Coletores/patologia , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Masculino , Feminino , Gotículas Lipídicas/metabolismo
4.
BMC Vet Res ; 20(1): 286, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961471

RESUMO

BACKGROUND: The milk's nutritional value is determined by its constituents, including fat, protein, carbohydrates, and minerals. The mammary gland's ability to produce milk is controlled by a complex network of genes. Thereby, the fat, protein, and lactose synthesis must be boost in milk to increase milk production efficiency. This can be accomplished by fusing genetic advancements with proper management practices. Therefore, this study aimed to investigate the association between the Lipoprotein lipase (LPL), kappa casein CSN3, and Glucose transporter 1 (GLUT1) genes expression levels and such milk components as fat, protein, and lactose in different dairy breeds during different stages of lactation. METHODS: To achieve such a purpose, 94 milk samples were collected (72 samples from 36 multiparous black-white and red-white Holstein-Friesian (HF) cows and 22 milk samples from 11 Egyptian buffaloes) during the early and peak lactation stages. The milk samples were utilized for milk analysis and genes expressions analyses using non- invasive approach in obtaining milk fat globules (MFGs) as a source of Ribonucleic acid (RNA). RESULTS: LPL and CSN3 genes expressions levels were found to be significantly higher in Egyptian buffalo than Holstein-Friesian (HF) cows as well as fat and protein percentages. On the other hand, GLUT1 gene expression level was shown to be significantly higher during peak lactation than early lactation. Moreover, lactose % showed a significant difference in peak lactation phase compared to early lactation phase. Also, fat and protein percentages were significantly higher in early lactation period than peak lactation period but lactose% showed the opposite pattern of Egyptian buffalo. CONCLUSION: Total RNA can be successfully obtained from MFGs. The results suggest that these genes play a role in glucose absorption and lactose synthesis in bovine mammary epithelial cells during lactation. Also, these results provide light on the differential expression of these genes among distinct Holstein-Friesian cow breeds and Egyptian buffalo subspecies throughout various lactation phases.


Assuntos
Caseínas , Glicolipídeos , Glicoproteínas , Lactação , Gotículas Lipídicas , Glândulas Mamárias Animais , Leite , RNA Mensageiro , Animais , Bovinos/genética , Lactação/genética , Feminino , Gotículas Lipídicas/metabolismo , Leite/química , Leite/metabolismo , Glicolipídeos/metabolismo , Caseínas/genética , Caseínas/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Glândulas Mamárias Animais/metabolismo , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Búfalos/genética , Búfalos/metabolismo , Lactose/metabolismo , Lactose/análise , Proteínas do Leite/análise , Proteínas do Leite/metabolismo , Proteínas do Leite/genética , Regulação da Expressão Gênica
5.
PLoS One ; 19(7): e0304736, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38968248

RESUMO

High throughput screening of small molecules and natural products is costly, requiring significant amounts of time, reagents, and operating space. Although microarrays have proven effective in the miniaturization of screening for certain biochemical assays, such as nucleic acid hybridization or antibody binding, they are not widely used for drug discovery in cell culture due to the need for cells to internalize lipophilic drug candidates. Lipid droplet microarrays are a promising solution to this problem as they are capable of delivering lipophilic drugs to cells at dosages comparable to solution delivery. However, the scalablility of the array fabrication, assay validation, and screening steps has limited the utility of this approach. Here we take several new steps to scale up the process for lipid droplet array fabrication, assay validation in cell culture, and drug screening. A nanointaglio printing process has been adapted for use with a printing press. The arrays are stabilized for immersion into aqueous solution using a vapor coating process. In addition to delivery of lipophilic compounds, we found that we are also able to encapsulate and deliver a water-soluble compound in this way. The arrays can be functionalized by extracellular matrix proteins such as collagen prior to cell culture as the mechanism for uptake is based on direct contact with the lipid delivery vehicles rather than diffusion of the drug out of the microarray spots. We demonstrate this method for delivery to 3 different cell types and the screening of 92 natural product extracts on a microarray covering an area of less than 0.1 cm2. The arrays are suitable for miniaturized screening, for instance in high biosafety level facilities where space is limited and for applications where cell numbers are limited, such as in functional precision medicine.


Assuntos
Gotículas Lipídicas , Humanos , Gotículas Lipídicas/metabolismo , Análise em Microsséries/métodos , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios de Triagem em Larga Escala/métodos
6.
Methods Enzymol ; 700: 77-104, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38971613

RESUMO

The biophysical drivers of membrane lateral heterogeneity, often termed lipid rafts, have been largely explored using synthetic liposomes or mammalian plasma membrane-derived giant vesicles. Yeast vacuoles, an organelle comparable to mammalian lysosomes, is the only in vivo system that shows stable micrometer scale phase separation in unperturbed cells. The ease of manipulating lipid metabolism in yeast makes this a powerful system for identifying lipids involved in the onset of vacuole membrane heterogeneity. Vacuole domains are induced by stationary stage growth and nutritional starvation, during which they serve as a docking and internalization site for lipid droplet energy stores. Here we describe methods for characterizing vacuole phase separation, its physiological function, and its lipidic drivers. First, we detail methodologies for robustly inducing vacuole domain formation and quantitatively characterizing during live cell imaging experiments. Second, we detail a new protocol for biochemical isolation of stationary stage vacuoles, which allows for lipidomic dissection of membrane phase separation. Third, we describe biochemical techniques for analyzing lipid droplet internalization in vacuole domains. When combined with genetic or chemical perturbations to lipid metabolism, these methods allow for systematic dissection of lipid composition in the structure and function of ordered membrane domains in living cells.


Assuntos
Metabolismo dos Lipídeos , Saccharomyces cerevisiae , Vacúolos , Vacúolos/metabolismo , Saccharomyces cerevisiae/metabolismo , Microdomínios da Membrana/metabolismo , Gotículas Lipídicas/metabolismo , Membrana Celular/metabolismo , Lipidômica/métodos
7.
J Cell Biol ; 223(9)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38949658

RESUMO

Contact sites between lipid droplets and other organelles are essential for cellular lipid and energy homeostasis upon metabolic demands. Detection of these contact sites at the nanometer scale over time in living cells is challenging. We developed a tool kit for detecting contact sites based on fluorogen-activated bimolecular complementation at CONtact sites, FABCON, using a reversible, low-affinity split fluorescent protein, splitFAST. FABCON labels contact sites with minimal perturbation to organelle interaction. Via FABCON, we quantitatively demonstrated that endoplasmic reticulum (ER)- and mitochondria (mito)-lipid droplet contact sites are dynamic foci in distinct metabolic conditions, such as during lipid droplet biogenesis and consumption. An automated analysis pipeline further classified individual contact sites into distinct subgroups based on size, likely reflecting differential regulation and function. Moreover, FABCON is generalizable to visualize a repertoire of organelle contact sites including ER-mito. Altogether, FABCON reveals insights into the dynamic regulation of lipid droplet-organelle contact sites and generates new hypotheses for further mechanistical interrogation during metabolic regulation.


Assuntos
Retículo Endoplasmático , Gotículas Lipídicas , Mitocôndrias , Gotículas Lipídicas/metabolismo , Humanos , Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/genética , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Metabolismo dos Lipídeos , Células HeLa , Células HEK293 , Proteínas Luminescentes/metabolismo , Proteínas Luminescentes/genética
8.
Stem Cell Res Ther ; 15(1): 223, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044210

RESUMO

BACKGROUND: Hepatic stellate cells (HSC) have numerous critical roles in liver function and homeostasis, while they are also known for their importance during liver injury and fibrosis. There is therefore a need for relevant in vitro human HSC models to fill current knowledge gaps. In particular, the roles of vitamin A (VA), lipid droplets (LDs), and energy metabolism in human HSC activation are poorly understood. METHODS: In this study, human pluripotent stem cell-derived HSCs (scHSCs), benchmarked to human primary HSC, were exposed to 48-hour starvation of retinol (ROL) and palmitic acid (PA) in the presence or absence of the potent HSC activator TGF-ß. The interventions were studied by an extensive set of phenotypic and functional analyses, including transcriptomic analysis, measurement of activation-related proteins and cytokines, VA- and LD storage, and cell energy metabolism. RESULTS: The results show that though the starvation of ROL and PA alone did not induce scHSC activation, the starvation amplified the TGF-ß-induced activation-related transcriptome. However, TGF-ß-induced activation alone did not lead to a reduction in VA or LD stores. Additionally, reduced glycolysis and increased mitochondrial fission were observed in response to TGF-ß. CONCLUSIONS: scHSCs are robust models for activation studies. The loss of VA and LDs is not sufficient for scHSC activation in vitro, but may amplify the TGF-ß-induced activation response. Collectively, our work provides an extensive framework for studying human HSCs in healthy and diseased conditions.


Assuntos
Células Estreladas do Fígado , Ácido Palmítico , Fator de Crescimento Transformador beta , Vitamina A , Humanos , Vitamina A/farmacologia , Vitamina A/metabolismo , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Ácido Palmítico/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/efeitos dos fármacos , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/efeitos dos fármacos , Células-Tronco Pluripotentes/citologia , Metabolismo Energético/efeitos dos fármacos
9.
Lipids Health Dis ; 23(1): 218, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030618

RESUMO

Lipid droplets (LDs), which are active organelles, derive from the monolayer membrane of the endoplasmic reticulum and encapsulate neutral lipids internally. LD-associated proteins like RAB, those in the PLIN family, and those in the CIDE family participate in LD formation and development, and they are active players in various diseases, organelles, and metabolic processes (i.e., obesity, non-alcoholic fatty liver disease, and autophagy). Our synthesis on existing research includes insights from the formation of LDs to their mechanisms of action, to provide an overview needed for advancing research into metabolic diseases and lipid metabolism.


Assuntos
Autofagia , Gotículas Lipídicas , Metabolismo dos Lipídeos , Doenças Metabólicas , Hepatopatia Gordurosa não Alcoólica , Humanos , Gotículas Lipídicas/metabolismo , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Retículo Endoplasmático/metabolismo , Obesidade/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
10.
Int J Mol Sci ; 25(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38999988

RESUMO

The orchestration of cellular metabolism and redox balance is a complex, multifaceted process crucial for maintaining cellular homeostasis. Lipid droplets (LDs), once considered inert storage depots for neutral lipids, are now recognized as dynamic organelles critical in lipid metabolism and energy regulation. Mitochondria, the powerhouses of the cell, play a central role in energy production, metabolic pathways, and redox signaling. The physical and functional contacts between LDs and mitochondria facilitate a direct transfer of lipids, primarily fatty acids, which are crucial for mitochondrial ß-oxidation, thus influencing energy homeostasis and cellular health. This review highlights recent advances in understanding the mechanisms governing LD-mitochondria interactions and their regulation, drawing attention to proteins and pathways that mediate these contacts. We discuss the physiological relevance of these interactions, emphasizing their role in maintaining energy and redox balance within cells, and how these processes are critical in response to metabolic demands and stress conditions. Furthermore, we explore the pathological implications of dysregulated LD-mitochondria interactions, particularly in the context of metabolic diseases such as obesity, diabetes, and non-alcoholic fatty liver disease, and their potential links to cardiovascular and neurodegenerative diseases. Conclusively, this review provides a comprehensive overview of the current understanding of LD-mitochondria interactions, underscoring their significance in cellular metabolism and suggesting future research directions that could unveil novel therapeutic targets for metabolic and degenerative diseases.


Assuntos
Gotículas Lipídicas , Metabolismo dos Lipídeos , Mitocôndrias , Humanos , Gotículas Lipídicas/metabolismo , Mitocôndrias/metabolismo , Animais , Metabolismo Energético , Oxirredução , Doenças Metabólicas/metabolismo , Homeostase
11.
J Transl Med ; 22(1): 659, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010173

RESUMO

BACKGROUND: Spinal cord injury (SCI) is characterized by extensive demyelination and inflammatory responses. Facilitating the clearance of lipid droplets (LDs) within microglia contributes to creating a microenvironment that favors neural recovery and provides essential materials for subsequent remyelination. Therefore, investigating MicroRNAs (miRNAs) that regulate lipid homeostasis after SCI and elucidating their potential mechanisms in promoting LDs clearance in microglia have become focal points of SCI research. METHODS: We established a subacute C5 hemicontusion SCI model in mice and performed transcriptomic sequencing on the injury epicenter to identify differentially expressed genes and associated pathways. Confocal imaging was employed to observe LDs accumulation. Multi-omics analyses were conducted to identify differentially expressed mRNA and miRNA post-SCI. Pathway enrichment analysis and protein-protein interaction network construction were performed using bioinformatics methods, revealing miR-223-Abca1 as a crucial miRNA-mRNA pair in lipid metabolism regulation. BV2 microglia cell lines overexpressing miR-223 were engineered, and immunofluorescence staining, western blot, and other techniques were employed to assess LDs accumulation, relevant targets, and inflammatory factor expression, confirming its role in regulating lipid homeostasis in microglia. RESULTS: Histopathological results of our hemicontusion SCI model confirmed LDs aggregation at the injury epicenter, predominantly within microglia. Our transcriptomic analysis during the subacute phase of SCI in mice implicated ATP-binding cassette transporter A1 (Abca1) as a pivotal gene in lipid homeostasis, cholesterol efflux and microglial activation. Integrative mRNA-miRNA multi-omics analysis highlighted the crucial role of miR-223 in the neuroinflammation process following SCI, potentially through the regulation of lipid metabolism via Abca1. In vitro experiments using BV2 cells overexpressing miR-223 demonstrated that elevated levels of miR-223 enhance ABCA1 expression in myelin debris and LPS-induced BV2 cells. This promotes myelin debris degradation and LDs clearance, and induces a shift toward an anti-inflammatory M2 phenotype. CONCLUSIONS: In summary, our study unveils the critical regulatory role of miR-223 in lipid homeostasis following SCI. The mechanism by which this occurs involves the upregulation of ABCA1 expression, which facilitates LDs clearance and myelin debris degradation, consequently alleviating the lipid burden, and inhibiting inflammatory polarization of microglia. These findings suggest that strategies to enhance miR-223 expression and target ABCA1, thereby augmenting LDs clearance, may emerge as appealing new clinical targets for SCI treatment.


Assuntos
Transportador 1 de Cassete de Ligação de ATP , Gotículas Lipídicas , Camundongos Endogâmicos C57BL , MicroRNAs , Microglia , Traumatismos da Medula Espinal , Regulação para Cima , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , MicroRNAs/metabolismo , MicroRNAs/genética , Microglia/metabolismo , Microglia/patologia , Animais , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Gotículas Lipídicas/metabolismo , Camundongos , Linhagem Celular , Masculino , Metabolismo dos Lipídeos/genética
12.
Viruses ; 16(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38932200

RESUMO

The replication of species A rotaviruses (RVAs) involves the recruitment of and interaction with cellular organelles' lipid droplets (LDs), both physically and functionally. The inhibition of enzymes involved in the cellular fatty acid biosynthesis pathway or the inhibition of cellular lipases that degrade LDs was found to reduce the functions of 'viral factories' (viroplasms for rotaviruses or replication compartments of other RNA viruses) and decrease the production of infectious progeny viruses. While many other RNA viruses utilize cellular lipids for their replication, their detailed analysis is far beyond this review; only a few annotations are made relating to hepatitis C virus (HCV), enteroviruses, SARS-CoV-2, and HIV-1.


Assuntos
Metabolismo dos Lipídeos , Vírus de RNA , Rotavirus , Replicação Viral , Rotavirus/metabolismo , Rotavirus/fisiologia , Rotavirus/genética , Humanos , Vírus de RNA/metabolismo , Vírus de RNA/genética , Vírus de RNA/fisiologia , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/virologia , Animais
13.
Nat Commun ; 15(1): 5489, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942786

RESUMO

Lipid droplets (LDs) are dynamic lipid storage organelles. They are tightly linked to metabolism and can exert protective functions, making them important players in health and disease. Most LD studies in vivo rely on staining methods, providing only a snapshot. We therefore developed a LD-reporter mouse by labelling the endogenous LD coat protein perilipin 2 (PLIN2) with tdTomato, enabling staining-free fluorescent LD visualisation in living and fixed tissues and cells. Here we validate this model under standard and high-fat diet conditions and demonstrate that LDs are highly abundant in various cell types in the healthy brain, including neurons, astrocytes, ependymal cells, neural stem/progenitor cells and microglia. Furthermore, we also show that LDs are abundant during brain development and can be visualized using live imaging of embryonic slices. Taken together, our tdTom-Plin2 mouse serves as a novel tool to study LDs and their dynamics under both physiological and diseased conditions in all tissues expressing Plin2.


Assuntos
Encéfalo , Gotículas Lipídicas , Perilipina-2 , Animais , Perilipina-2/metabolismo , Perilipina-2/genética , Gotículas Lipídicas/metabolismo , Encéfalo/metabolismo , Camundongos , Neurônios/metabolismo , Técnicas de Introdução de Genes , Camundongos Transgênicos , Feminino , Proteínas Luminescentes/metabolismo , Proteínas Luminescentes/genética , Masculino , Astrócitos/metabolismo , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/citologia , Microglia/metabolismo
14.
J Mater Chem B ; 12(26): 6384-6393, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38845563

RESUMO

Type I photodynamic therapy is considered to be a more promising cancer treatment than type II photodynamic therapy due to its non-oxygen-dependent characteristics. In this work, three D-A structure N,N'-dihydrophenazine (DHP)-based photosensitizers DP-CNPY, SMP-CNPY and DMP-CNPY were designed and synthesized by introducing different numbers of methyl groups in the backbone neighbor of DHP as the donor and combined with the typical strong electron acceptor 2-(pyridin-4-yl)acetonitrile. Among the three photosensitizers, SMP-CNPY with one methyl modification showed the best type I ROS (O2-˙, ˙OH) generation capacity and AIE performance. By encapsulation, SMP-CNPY was fabricated into nanoparticles, and SMP-CNPY NPs exhibited lipid droplet targeting ability with near-infrared (NIR) emission. Cell experiments have proved that SMP-CNPY NPs can effectively kill different kinds of cancer cells under normal oxygen conditions. Even under hypoxic and extreme hypoxic conditions, SMP-CNPY NPs can still produce ROS and kill cancer cells. This work holds significant potential in the field of type I AIE-active photosensitizers and provides a new strategy for overcoming the hypoxic dilemma in the malignant tumor microenvironment.


Assuntos
Gotículas Lipídicas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/síntese química , Humanos , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas/química , Tamanho da Partícula , Imagem Óptica , Sobrevivência Celular/efeitos dos fármacos , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral
15.
Food Funct ; 15(13): 6783-6797, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38828877

RESUMO

In most parts of the world, life expectancy is increasing thanks to improved healthcare, public health policies, nutrition, and treatment. This increase in lifespan is often not accompanied by an increase in health span, which severely affects people as they age. One notable consequence of this is the increasing prevalence of neurodegenerative diseases such as mild cognitive impairment, dementia, and Alzheimer's disease. Therefore, dietary and pharmaceutical measures must be taken to reduce the burden of such pathologies. Among the different types of nutrients found in the diet, lipids and especially polar lipids are very important for cognition due to their abundance in the brain. Amid the most studied sources of polar lipids, milk fat globule membrane (MFGM) stands out as it is abundant in industrial by-products such as buttermilk. In this narrative review, we discuss the latest, i.e. less than five years old, scientific evidence on the use of MFGM and its polar lipids in cognitive neurodevelopment in early life and their potential effect in preventing neurodegeneration in old age. We conclude that MFGM is an interesting, abundant and exploitable source of relatively inexpensive bioactive molecules that could be properly formulated and utilized in the areas of neurodevelopment and cognitive decline. Sufficiently large randomized controlled trials are required before health-related statements can be made. However, research in this area is progressing rapidly and the evidence gathered points to biological, health-promoting effects.


Assuntos
Cognição , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Glicolipídeos/química , Gotículas Lipídicas/química , Glicoproteínas/química , Humanos , Cognição/efeitos dos fármacos , Animais , Lipídeos/química
16.
J Colloid Interface Sci ; 672: 256-265, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38838633

RESUMO

HYPOTHESIS: Understanding the digestion of lipid-based pharmaceutical formulations and food systems is necessary for optimising drug and nutrient delivery and has been extensively studied in bulk emulsion systems using the pH-stat method [1]. However, this approach is not suitable for investigation of individual lipid droplets, in particular the interface where the lipase acts. Microfluidic approaches to study digestion at lipid-water interfaces using droplet trapping have been proposed, however the aqueous phase in that case washes over the interface presenting uncertainty over the stoichiometry of interactions [2]. The internal interface of a Janus-like droplet, containing distinct aqueous and lipid compartments, mimics the interface of a lipid droplet in aqueous solution with controlled stoichiometry [3]. Hence, it was hypothesised that the internal interface of Janus droplets can offer a precise way to study the enzymatic digestion of lipids formulations. EXPERIMENTS: Using microfluidic methods, Janus-like droplets were formed by coalescing emulsion droplets containing lipid formulation and pancreatic lipase. Polarised light microscopy (PLM) and in-situ small-angle X-ray scattering (SAXS) were used to investigate the droplets. FINDINGS: PLM revealed the growth of an aligned inverse hexagonal phase (H2), and with SAXS showed that this phase transformation and alignment resulted from enzymatic digestion. A subsequent partial transformation from H2 to inverse bicontinuous cubic phase occurred when simulated intestinal fluid was used instead of Tris buffer. Suggesting that phospholipids and bile salts could diffuse across the internal interface to locally affect their surroundings.


Assuntos
Lipase , Lipase/química , Lipase/metabolismo , Transição de Fase , Emulsões/química , Tamanho da Partícula , Espalhamento a Baixo Ângulo , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Lipídeos/química , Difração de Raios X , Propriedades de Superfície
17.
STAR Protoc ; 5(2): 102977, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38875117

RESUMO

By differentiating into mature adipocytes, 3T3-L1 cells can be utilized as a model cell line to investigate (pre)adipocyte function in vitro. Here, we present a protocol for combining qualitative and quantitative analysis of lipid droplets in mature 3T3-L1 adipocytes using oil red O. We describe steps to differentiate 3T3-L1 preadipocytes to adipocytes and give detailed procedures to determine total lipid amount as well as lipid droplet size and number using microscopic devices and an ImageJ macro. For complete details on the use and execution of this protocol, please refer to Kaczmarek et al.1.


Assuntos
Células 3T3-L1 , Adipócitos , Compostos Azo , Gotículas Lipídicas , Animais , Camundongos , Adipócitos/metabolismo , Adipócitos/citologia , Gotículas Lipídicas/metabolismo , Compostos Azo/química , Diferenciação Celular , Coloração e Rotulagem/métodos , Metabolismo dos Lipídeos
18.
Front Biosci (Landmark Ed) ; 29(6): 209, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38940024

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a prevalent condition characterized by hepatic fat accumulation, often progressing to severe liver injury, for which approved treatments are currently lacking. This study explores the potential therapeutic impact of alpha-lipoic acid (ALA), a natural compound crucial in lipid metabolism, on NAFLD using an in vitro model. METHODS: HepG2 cells were treated with a palmitic acid:oleic acid (PA:OA) mixture, representing a cellular model of steatosis. Subsequent treatment with ALA at concentrations of 1 µM and 5 µM aimed to evaluate its effects on lipid content and metabolism. Real-time polymerase chain reaction (PCR), BODIPY staining, cytofluorimetric analysis, and lipidomics were used to assess gene expression, lipid droplet accumulation, and fatty acid profiles. RESULTS: Our results showed that ALA significantly reduced lipid droplets in PA:OA-treated HepG2 cells, with a concentration-dependent effect. Analysis of fatty acid profiles demonstrated a decrease in palmitic acid levels with ALA treatment, while oleic acid reduction was observed only at the higher concentration. Moreover, ALA modulated the expression of genes involved in cholesterol biosynthesis and low-density lipoprotein (LDL) metabolism, indicating a potential role in lipid homeostasis. Further insights into molecular mechanisms revealed that ALA modulated peroxisome proliferator activated receptors (PPARs), specifically PPAR-alpha and PPAR-gamma, involved in fatty acid metabolism and insulin sensitivity. Finally, ALA counteracted the overexpression of thermogenic genes induced by exogenous fatty acids, suggesting a regulatory role in energy dissipation pathways. CONCLUSION: In conclusion, this study highlights ALA as a therapeutic agent in mitigating lipid accumulation and dysregulation in NAFLD.


Assuntos
Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica , Ácido Oleico , Ácido Palmítico , Ácido Tióctico , Humanos , Ácido Tióctico/farmacologia , Células Hep G2 , Metabolismo dos Lipídeos/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Ácido Oleico/farmacologia , Ácido Oleico/metabolismo , Ácido Palmítico/farmacologia , Ácido Palmítico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Ácidos Graxos/metabolismo , PPAR gama/metabolismo , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/efeitos dos fármacos , PPAR alfa/metabolismo , PPAR alfa/genética , Proteína Desacopladora 2/metabolismo , Proteína Desacopladora 2/genética
19.
Food Res Int ; 190: 114601, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945615

RESUMO

Lipids from cow milk fat globule membranes (MFGMs) and extracellular vesicles (EVs) are considered beneficial for neurodevelopment, cognitive maintenance and human health in general. Nevertheless, it is largely unknown whether intake of infant formulas and medical nutrition products rich in these particles promote accretion of specific lipids and whether this affects metabolic homeostasis. To address this, we carried out a 16-week dietary intervention study where mice were supplemented with a MFGM/EV-rich concentrate, a control diet supplemented with a whey protein concentrate and devoid of milk lipids, or regular chow. Assessment of commonly used markers of metabolic health, including body weight, glucose intolerance and liver microanatomy, demonstrated no differences across the dietary regimes. In contrast, in-depth lipidomic analysis revealed accretion of milk-derived very long odd-chain sphingomyelins and ceramides in blood plasma and multiple tissues of mice fed the MFGM/EV diet. Furthermore, lipidomic flux analysis uncovered that mice fed the MFGM/EV diet have increased lipid metabolic turnover at the whole-body level. These findings help fill a long-lasting knowledge gap between the intake of MFGM/EV-containing foods and the health-promoting effects of their lipid constituents. In addition, the findings suggest that dietary sphingomyelins or ceramide-breakdown products with very long-chains can be used as structural components of cellular membranes, lipoprotein particles and signaling molecules that modulate metabolic homeostasis and health.


Assuntos
Vesículas Extracelulares , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Metabolismo dos Lipídeos , Esfingolipídeos , Animais , Esfingolipídeos/metabolismo , Vesículas Extracelulares/metabolismo , Camundongos , Glicolipídeos/metabolismo , Gotículas Lipídicas/metabolismo , Glicoproteínas/metabolismo , Lipidômica , Camundongos Endogâmicos C57BL , Masculino , Esfingomielinas/metabolismo , Ceramidas/metabolismo , Dieta , Fígado/metabolismo , Suplementos Nutricionais
20.
J Nutr Sci Vitaminol (Tokyo) ; 70(3): 273-279, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38945893

RESUMO

The purpose of this study was to examine whether 4 wk of daily ingestion of milk fat globule membrane (MFGM) combined with exercise training improves physical performance-muscle strength, agility and muscle power-in healthy young adults. The study was designed as a randomized, double-blind, and placebo-controlled trial. Twenty healthy young adults received either an MFGM powder containing 1.6 g of fat and 160 mg of sphingomyelin or an isocaloric placebo powder daily throughout 4 wk of power or agility training. Physical performance tests and body composition measurements were conducted before and after the 4-wk intervention. Ingestion of MFGM did not affect isometric or isokinetic muscle strength, but it was associated with a greater increase in vertical jump peak power compared with placebo. There were no significant changes in body weight or lean body mass during the intervention period in either group, and no significant differences between groups. We conclude that daily MFGM supplementation combined with exercise training has the potential to improve physical performance in young adults; however, further studies with larger sample sizes should be conducted to obtain more evidence supporting achievement of improved physical performance through MFGM supplementation.


Assuntos
Composição Corporal , Suplementos Nutricionais , Exercício Físico , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Força Muscular , Humanos , Método Duplo-Cego , Glicolipídeos/administração & dosagem , Glicolipídeos/farmacologia , Glicoproteínas/administração & dosagem , Masculino , Adulto Jovem , Feminino , Força Muscular/efeitos dos fármacos , Exercício Físico/fisiologia , Projetos Piloto , Adulto , Desempenho Físico Funcional , Peso Corporal , Esfingomielinas/administração & dosagem , Músculo Esquelético/fisiologia , Músculo Esquelético/efeitos dos fármacos
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