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1.
Int J Mol Sci ; 24(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36674616

RESUMO

Novel biodegradable metal alloys are increasingly used as implant materials. The implantation can be accompanied by an inflammatory response to a foreign object. For studying inflammation in the implantation area, non-invasive imaging methods are needed. In vivo imaging for the implanted area and its surroundings will provide beneficiary information to understand implant-related inflammation and help to monitor it. Therefore, inflammation-sensitive fluorescent liposomes in rats were tested in the presence of an implant to evaluate their usability in studying inflammation. The sphingomyelin-containing liposomes carrying alpha-melanocyte-stimulating hormone (α-MSH)-peptide were tested in a rat bone implant model. The liposome interaction with implant material (Mg-10Gd) was analyzed with Mg-based implant material (Mg-10Gd) in vitro. The liposome uptake process was studied in the bone-marrow-derived macrophages in vitro. Finally, this liposomal tracer was tested in vivo. It was found that α-MSH coupled sphingomyelin-containing liposomes and the Mg-10Gd implant did not have any disturbing influence on each other. The clearance of liposomes was observed in the presence of an inert and biodegradable implant. The degradable Mg-10Gd was used as an alloy example; however, the presented imaging system offers a new possible use of α-MSH-SM-liposomes as tools for investigating implant responses.


Assuntos
Lipossomos , alfa-MSH , Ratos , Animais , Esfingomielinas , Implantes Absorvíveis , Inflamação
2.
J Exp Clin Cancer Res ; 42(1): 33, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36691044

RESUMO

BACKGROUND: With increasing incidence and mortality, colorectal cancer (CRC) seriously endangers human health. LARP6, a member of La-related protein (LARP) family, is a RNA binding protein and probably associates with CRC progression, but its specific roles and mechanisms in CRC still remain unknown. METHOD: Quantitative real-time PCR (qPCR), western blot, and immunohistochemistry were employed to examine LARP6 expression in CRC tissues. Using the stable LARP6 overexpression or interference CRC cell lines, the effect of LARP6 on CRC progression were evaluated. High-throughput RNA immunoprecipitation sequencing (RIP-seq) and a series of relevant experiments were conducted to explain how LARP6 functions. SPSS software was used for statistical analysis. RESULT: In this study, we found that LARP6 expression is downregulated in CRC and correlates with patients' overall survival and relapse-free survival. Furthermore, altered LARP6 expression influences CRC cells invasion and metastasis. Mechanically, we discovered that LARP6 bind ZNF267 mRNA and regulated its stability and translation. LARP6 inhibited expression of SGMS2, a downstream target of ZNF267, resulting in ceramide and sphingomyelin imbalance in CRC cells. Interestingly, LARP6 also enhances autophagy activity of CRC cells, and the effect was at least partially determined by the inhibition of SGMS2-mediated sphingomyelin synthesis. CONCLUSION: Our study showed how LARP6/ZNF267/SGMS2 axis influence CRC progression, which contributes to further understanding of the molecular mechanisms underlying CRC development.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , Esfingomielinas , Proteínas de Ligação a RNA/genética , RNA Mensageiro/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Linhagem Celular Tumoral , MicroRNAs/genética
3.
Anim Reprod Sci ; 248: 107184, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36587591

RESUMO

The definition of new reliable markers for neonatal maturity evaluation is crucial in canine clinical practice. Concerns about the safety of amniotic sampling in pregnant dogs have prevented its collection for diagnostic purposes. Moreover, amniotic fluid had been considered waste material until the latest studies reported amniocentesis as a reliable and safe procedure, even in the canine species. In our study, amniotic fluid (n = 63) collected at birth from ten dogs undergoing elective Caesarean sections at term was analysed to discover new potential indices of canine neonatal maturity. Based on gestational age, mothers and puppies were divided into two groups: the early group (≤65 days from luteinizing hormone (LH) surge, n = 5) and the late group (>65 days from LH surge, n = 5). Amniotic parameters of the lightest and heaviest puppy in individual/each litter, with a birth weight difference of at least 20% among littermates, were also compared. In particular, the content of lecithin, sphingomyelin, surfactant protein A (SP-A), cortisol, and pentraxin 3 (PTX3) in amniotic fluid, which is considered predictive of foetal development in humans, were investigated. Maternal serum SP-A and cortisol were also measured simultaneously. All amniotic parameters were detectable in canine amniotic fluid. Interestingly, the concentrations of different amniotic parameters correlated with each other. Lecithin was positively correlated with sphingomyelin (p < 0.0001), maternal SP-A (p < 0.0005), and the ratio of amniotic and maternal cortisol (p < 0.004). Amniotic SP-A was inversely correlated to maternal SP-A (p < 0.05), lecithin (p < 0.005), and lecithin-sphingomyelin ratio (p < 0.05). A positive correlation was also recorded between amniotic and maternal cortisol (p < 0.008). Considering that all puppies were born alive and mature, these data could provide a potential range of expected amniotic values in full-term new-born dogs. Furthermore, since gestational age was positively correlated with both maternal and amniotic cortisol (p < 0.0001) and amniotic PTX3 (p < 0.05), amniotic fluid seems to be an attractive, innovative, and minimally invasive matrix with potential diagnostic and prognostic utility for the investigation of canine maturity.


Assuntos
Líquido Amniótico , Lecitinas , Animais , Cães , Feminino , Gravidez , Líquido Amniótico/metabolismo , Idade Gestacional , Hidrocortisona/metabolismo , Parto , Esfingomielinas/análise , Esfingomielinas/metabolismo
4.
Chem Phys Lipids ; 250: 105271, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36509110

RESUMO

In the past several years there has been a rapid rise in the use of lipid-based drug formulations. In the case of intravenous drug administration the interaction of lipid carrier with serum albumin is crucial for the distribution of the bioactive molecules in the bloodstream and reaching the target tissue. In this work, we have explored the interaction of serum albumin with three-component lipid monolayer build of palmitoyloleoylphosphatidylcholine (POPC), sphingomyelin (SM), and cholesterol (Chol). Using wide range of lipid compositions and various concentrations of serum albumin we identified the factors governing the lipid-protein binding. Our study revealed that albumin can penetrate selectively the monolayers of POPC/SM/Chol depending on the lipid composition in the mixture. Moreover, the interaction of albumin with monolayer can be controlled by the molecular density of the film and the concentration of protein. The adsorbed albumin exists in the film on the top of lipid monolayer. This behavior may lead to the increase of the size and charge of the lipid carrier and affect the drug transport throughout the bloodstream. The results of this work provide essential physicochemical data that can be used for predicting the pharmacokinetic profile of lipid-based formulations.


Assuntos
Portadores de Fármacos , Albumina Sérica , Albumina Sérica/metabolismo , Fosfatidilcolinas/química , Colesterol/química , Esfingomielinas/química , Ligação Proteica
5.
Methods Mol Biol ; 2613: 111-125, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36587075

RESUMO

Sphingolipids are ubiquitously expressed in eukaryotes and play various functional roles. The key characteristic of sphingolipids is their diversity of molecular species. Sphingomyelin (SM) and glycosphingolipids (GSLs) are the major components of sphingolipids in the plasma membrane, which are composed of ceramide and a polar head-group. SM is the most abundant sphingolipid species in mammalian cells, while GSLs have a wide variety of glycans as head groups. Various fatty acids in ceramide also contribute to the diversity of sphingolipid species. To analyze the cellular function of each sphingolipid species, precise gene manipulation is essential. Recent developments in genome editing technologies have facilitated complete gene disruption in cultured cells. This chapter describes protocols for the construction of various sphingolipid-related gene knockout HeLa cells using the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 system and for confirmation of changes in their lipid composition using radioisotopes and thin layer chromatography. This sphingolipid-remodeled cell panel is a useful tool for analyzing the cellular functions of sphingolipid species and as a reference for lipid analysis.


Assuntos
Edição de Genes , Esfingolipídeos , Animais , Humanos , Esfingolipídeos/metabolismo , Edição de Genes/métodos , Células HeLa , Ceramidas/metabolismo , Esfingomielinas/metabolismo , Glicoesfingolipídeos , Sistemas CRISPR-Cas , Mamíferos/metabolismo
6.
Biophys Chem ; 293: 106947, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36566720

RESUMO

Knowing how a bioactive compound interacts with cell membranes is important to understand its effect at the molecular level. In this sense, this work aimed to study the interaction of lysicamine, an alkaloid with action against lung cancer cell lines, with lipid monolayers as cell membrane models. We employed two lipid mixtures: the first composed of 35% DOPC, 30% DOPE, 20% sphingomyelin, and 15% cholesterol as healthy cell membranes models (MM1), and the second replacing DOPC with DOPS as cancer cells models (MM2). The interaction of lysicamine with the monolayers was evaluated using tensiometry, Brewster angle microscopy (BAM), and polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS). Lysicamine had interfacial effects in both membrane models. For MM 1, it expanded the lipid monolayer and changed the interfacial rheological properties, increasing the in-plane elasticity of the films. PM-IRRAS spectra suggested a higher conformational disorder of the alkyl chains of the lipids. For MM 2, lysicamine also shifted the isotherms to higher areas, expanding the monolayers, but with no significant alteration in their interfacial rheological properties. PM-IRRAS spectra also suggested higher disorder in the orientation of the lipid alkyl chains upon lysicamine incorporation. For both models, BAM did not show alteration in interfacial aggregation upon drug incorporation. In conclusion, changes in some interfacial properties of membrane models caused by lysicamine depend on the monolayer composition, which can be associated with its bioactivity in cellular membranes.


Assuntos
Esfingomielinas , Água , Água/química , Espectrofotometria Infravermelho , Membrana Celular , Esfingomielinas/química , Propriedades de Superfície
7.
Sci Rep ; 12(1): 21715, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522440

RESUMO

The menopause can lead to epidermal changes that are alleviated by hormone replacement therapy (HRT). We hypothesise that these changes could relate to altered ceramide production, and that oestrogen may have a role in keratinocyte ceramide metabolism. White Caucasian women were recruited into three groups: pre-menopausal (n = 7), post-menopausal (n = 11) and post-menopausal taking HRT (n = 10). Blood samples were assessed for hormone levels, transepidermal water loss was measured to assess skin barrier function, and stratum corneum lipids were sampled from photoprotected buttock skin. Ceramides and sphingomyelins were analysed by ultraperformance liquid chromatography with electrospray ionisation and tandem mass spectrometry. Post-menopausal stratum corneum contained lower levels of ceramides, with shorter average length; changes that were not evident in the HRT group. Serum oestradiol correlated with ceramide abundance and length. Ceramides had shorter sphingoid bases, indicating altered de novo ceramide biosynthesis. Additionally, post-menopausal women had higher sphingomyelin levels, suggesting a possible effect on the hydrolysis pathway. Treatment of primary human keratinocytes with oestradiol (10 nM) increased production of CER[NS] and CER[NDS] ceramides, confirming an effect of oestrogen on cutaneous ceramide metabolism. Taken together, these data show perturbed stratum corneum lipids post-menopause, and a role for oestrogen in ceramide production.


Assuntos
Ceramidas , Epiderme , Feminino , Humanos , Ceramidas/análise , Epiderme/metabolismo , Pele/metabolismo , Esfingomielinas/metabolismo , Menopausa , Terapia de Reposição Hormonal , Estrogênios/metabolismo , Estradiol/farmacologia
8.
Int J Mol Sci ; 23(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36499025

RESUMO

The obligate intracellular bacterium Chlamydia trachomatis is the major causative agent of bacterial sexually transmitted diseases worldwide. In infected cells, the ceramide transport protein (CERT) is recruited to inclusions, where C. trachomatis replicates using host-synthesized ceramide. The ceramide is converted to sphingomyelin (SM) by a chlamydial infection-dependent SM synthesis (cidSM-synthesis) pathway, which occurs even in the absence of the SM synthases (SMS)-1 and -2 of host cells. The ceramide mimetic compound (1R,3S)-HPA-12 and the nonmimetic compound E16A, both of which are potent inhibitors of CERT, repressed the proliferation of C. trachomatis in HeLa cells. Unexpectedly, (1R,3R)-HPA-12, a ceramide mimetic compound that lacks CERT inhibitory activity, also exhibited potent anti-chlamydial activity. Using endogenous SMS-knockout mutant HeLa cells, we revealed that (1R,3R)-HPA-12 mildly inhibited cidSM-synthesis. In addition, LC-MS analysis revealed that (1R,3R)-HPA-12 is converted to a phosphocholine-conjugated metabolite in an infection-dependent manner. Imaging analysis with a fluorescent analog of ceramide suggested that cidSM-synthesis occurs in the bacterial bodies and/or inclusions. Collectively, these results suggested that (1R,3R)-HPA-12 exerts its anti-chlamydia activity not only as an inhibitor of cidSM-synthesis, but also via putative toxic effects of its phosphocholine adduct, which is most likely produced by the cidSM-synthesis route.


Assuntos
Ceramidas , Esfingomielinas , Humanos , Esfingomielinas/metabolismo , Ceramidas/farmacologia , Ceramidas/metabolismo , Células HeLa , Fosforilcolina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Chlamydia trachomatis/metabolismo
9.
Biochem Biophys Res Commun ; 633: 23-25, 2022 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-36344153

RESUMO

Sphingomyelin has been considered as a merely structural lipid for many years. However, this organelle-specific lipid has many other roles, including increasing membrane molecular order, acting as a source of ceramide in cell signaling and apoptosis, and forming clusters/nanodomains with cholesterol and ceramide. This contribution is dedicated to Professor E. Carafoli, on occasion of his 90th anniversary.


Assuntos
Ceramidas , Esfingomielinas , Esfingomielinas/química , Ceramidas/química , Colesterol/química , Apoptose , Esfingomielina Fosfodiesterase
10.
Langmuir ; 38(46): 14290-14301, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36354380

RESUMO

Sphingolipids are an important class of lipids found in mammalian cell membranes with important structural and signaling roles. They differ from another major group of lipids, the glycerophospholipids, in the connection of their hydrocarbon chains to their headgroups. In this study, a combination of electrochemical and structural methods has been used to elucidate the effect of this difference on sphingolipid behavior in an applied electric field. N-Palmitoyl sphingomyelin forms bilayers of similar coverage and thickness to its close analogue di-palmitoyl phosphatidylcholine. Grazing incidence diffraction data show slightly closer packing and a smaller chain tilt angle from the surface normal. Electrochemical IR results at low charge density show that the difference in tilt angle is retained on deposition to form bilayers. The bilayers respond differently to increasing electric field strength: chain tilt angles increase for both molecules, but sphingomyelin chains remain tilted as field strength is further increased. This behavior is correlated with disruption of the hydrogen-bonding network of small groups of sphingomyelin molecules, which may have significance for the behavior of molecules in lipid rafts in the presence of strong fields induced by ion gradients or asymmetric distribution of charged lipids.


Assuntos
Bicamadas Lipídicas , Esfingomielinas , Animais , Esfingomielinas/química , Bicamadas Lipídicas/química , Fosfatidilcolinas , Membrana Celular , Microdomínios da Membrana , Mamíferos
11.
Nutrients ; 14(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36297086

RESUMO

In addition to sphingomyelin and ceramide, sugar derivatives of ceramides, hexosylceramides (HexCer) are the major circulating sphingolipids. We have shown that silencing of ABCA1 transmembrane protein function for instance in cases of loss of function of ABCA1 gene results in low levels of HDL as well as a concomitant reduction in plasma HexCer levels. However, proteins involved in hepatic synthesis and egress of HexCer from cells is not well known although ABCA1 seems to be indirectly controlling the HexCer plasma levels by supporting HDL synthesis. In this study, we hypothesized that protein(s) other than ABCA1 are involved in the transport of HexCer to HDL. Using an unbiased knockdown approach, we found that ATP-binding cassette transporter protein C10 (ABCC10) participates in the synthesis of HexCer and thereby affects egress to HDL in human hepatoma Huh-7 cells. Furthermore, livers from ABCC10 deficient mice had significantly lower levels of HexCer compared to wild type livers. These studies suggest that ABCC10 partakes in modulating the synthesis and subsequent efflux of HexCer to HDL in liver cells.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Ceramidas , Fígado , Animais , Humanos , Camundongos , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Ceramidas/metabolismo , Colesterol , Lipoproteínas HDL/metabolismo , Fígado/metabolismo , Esfingolipídeos/metabolismo , Esfingomielinas/metabolismo , Açúcares/metabolismo
12.
Anal Chem ; 94(45): 15729-15737, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36315965

RESUMO

Currently, single-cell lipidomic mass spectrometry (MS) techniques are mostly limited to detection of high-abundance phosphatidylcholines (PCs). Herein, for enhancing the coverage to low-abundance sphingolipids in single-cell analysis, in-tube solid-phase microextraction (SPME) was combined with a single-probe MS system for selective enrichment of sphingolipids during singe-cell sampling. From the results, a lab-made single probe with a 30 µm tip size proved to be able to resolve the axon from the cell body of neuron HT22 in ambient conditions. TiO2 was immobilized onto the inner wall of the transfer capillary of the single-probe device for online selective capture of sphingolipids in ammonia-acetonitrile and rapid desorption in formic acid-methanol. The results showed that the breakthrough volume of the capillary with sample loading flow rate at 500 nL/min was >14 µL. Standard experiments showed that the signals of cerebroside (CB), ceramide (Cer), and sphingomyelin (SM) were largely enhanced after selective capture in the coated capillary, while PCs were totally removed. The reusability (>10 times) and stability of the lab-made TiO2-coated capillary was verified. By introducing the coated capillary into the single-probe MS system, the new system proved to have low detection limits of SM, Cer, and CB (0.007-0.027 µg/mm2) and acceptable linearity (r > 0.98) and repeatability (RSD < 30%). Lipid coverage of the new method to SMs and CBs proved to be largely improved (SM, 21 vs 2; CB, 10 vs 0) with the new method in comparison to conventional single-probe MS without selective capture by ambient analysis of a single spot of rat cerebellum. Finally, the new system was used to perform single-neuron analysis of sphingolipids in the control and lipopolysaccharide (LPS)-treated HT22 with differentiation of the cell body from the axonal synapse. Results showed that 5 sphingolipids had significantly higher concentrations in the synapse than in the cell body, while 3 oxidized sphingolipids had significantly higher levels in the cell body than in the synapse. After LPS treatment, most of the sphingolipids largely decreased and became more accumulated in the synapse, providing new information on LPS-induced neuroinflammation.


Assuntos
Esfingolipídeos , Espectrometria de Massas em Tandem , Ratos , Animais , Espectrometria de Massas em Tandem/métodos , Corpo Celular , Lipopolissacarídeos , Ceramidas , Esfingomielinas , Sinapses , Neurônios
13.
Int J Mol Sci ; 23(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36293312

RESUMO

Carotid atherosclerosis represents a relevant healthcare problem, since unstable plaques are responsible for approximately 15% of neurologic events, namely transient ischemic attack and stroke. Although statins treatment has proven effective in reducing LDL-cholesterol and the onset of acute clinical events, a residual risk may persist suggesting the need for the detection of reliable molecular markers useful for the identification of patients at higher risk regardless of optimal medical therapy. In this regard, several lines of evidence show a relationship among specific biologically active plasma lipids, atherosclerosis, and acute clinical events. We performed a Selected Reaction Monitoring-based High Performance Liquid Chromatography-tandem Mass Spectrometry (SRM-based HPLC-MS/MS) analysis on plasma HDL, LDL, and VLDL fractions purified, by isopycnic salt gradient ultracentrifugation, from twenty-eight patients undergoing carotid endarterectomy, having either a "hard" or a "soft" plaque, with the aim of characterizing the specific lipidomic patterns associated with features of carotid plaque instability. One hundred and thirty lipid species encompassing different lipid (sub)classes were monitored. Supervised multivariate analysis showed that lipids belonging to phosphatidylethanolamine (PE), sphingomyelin (SM), and diacylglycerol (DG) classes mostly contribute to discrimination within each lipoprotein fraction according to the plaque typology. Differential analysis evidenced a significant dysregulation of LDL PE (38:6), SM (32:1), and SM (32:2) between the two groups of patients (adj. p-value threshold = 0.05 and log2FC ≥ |0.58|). Using this approach, some LDL-associated markers of plaque vulnerability have been identified, in line with the current knowledge of the key roles of these phospholipids in lipoprotein metabolism and cardiovascular disease. This proof-of-concept study reports promising results, showing that lipoprotein lipidomics may present a valuable approach for identifying new biomarkers of potential clinical relevance.


Assuntos
Aterosclerose , Inibidores de Hidroximetilglutaril-CoA Redutases , Placa Aterosclerótica , Humanos , Fosfatidiletanolaminas , Diglicerídeos , Esfingomielinas , Espectrometria de Massas em Tandem , Lipoproteínas , Fosfolipídeos , Colesterol , Biomarcadores , Lipoproteínas LDL
14.
Lipids Health Dis ; 21(1): 99, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209101

RESUMO

BACKGROUND: The prevalence of gestational diabetes mellitus (GDM) is increasing worldwide. There is increasing evidence that GDM is a heterogeneous disease with different subtypes. An important question in this context is whether impaired glucose tolerance (IGT), which is a typical feature of the disease, may already be present before pregnancy and manifestation of the disease. The latter type resembles in its clinical manifestation prediabetes that has not yet manifested as type 2 diabetes (T2DM). Altered lipid metabolism plays a crucial role in the disorder's pathophysiology. The aim was to investigate the role of lipids which are relevant in diabetes-like phenotypes in these both models with different time of initial onset of IGT. METHODS: Two rodent models reflecting different characteristics of human GDM were used to characterize changes in lipid metabolism occurring during gestation. Since the New Zealand obese (NZO)-mice already exhibit IGT before and during gestation, they served as a subtype model for GDM with preexisting IGT (preIGT) and were compared with C57BL/6 N mice with transient IGT acquired during gestation (aqIGT). While the latter model does not develop manifest diabetes even under metabolic stress conditions, the NZO mouse is prone to severe disease progression later in life. Metabolically healthy Naval Medical Research Institute (NMRI) mice served as controls. RESULTS: In contrast to the aqIGT model, preIGT mice showed hyperlipidemia during gestation with elevated free fatty acids (FFA), triglycerides (TG), and increased atherogenic index. Interestingly, sphingomyelin (SM) concentrations in the liver decreased during gestation concomitantly with an increase in the sphingosine-1-phosphate (S1P) concentration in plasma. Further, preIGT mice showed impaired hepatic weight adjustment and alterations in hepatic FFA metabolism during gestation. This was accompanied by decreased expression of peroxisome proliferator-activated receptor alpha (PPARα) and lack of translocation of fatty acid translocase (FAT/CD36) to the hepatocellular plasma membrane. CONCLUSION: The preIGT model showed impaired lipid metabolism both in plasma and liver, as well as features of insulin resistance consistent with increased S1P concentrations, and in these characteristics, the preIGT model differs from the common GDM subtype with aqIGT. Thus, concomitantly elevated plasma FFA and S1P concentrations, in addition to general shifts in sphingolipid fractions, could be an interesting signal that the metabolic disorder existed before gestation and that future pregnancies require more intensive monitoring to avoid complications. This graphical abstract was created with BioRender.com .


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Intolerância à Glucose , Animais , Diabetes Gestacional/genética , Ácidos Graxos não Esterificados , Feminino , Teste de Tolerância a Glucose , Humanos , Metabolismo dos Lipídeos , Lisofosfolipídeos , Camundongos , Camundongos Endogâmicos C57BL , PPAR alfa , Gravidez , Esfingolipídeos , Esfingomielinas , Esfingosina/análogos & derivados , Triglicerídeos
15.
J Agric Food Chem ; 70(42): 13808-13817, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36239443

RESUMO

Quantifying sphingomyelin (SM) species by infusion-based mass spectrometry (MS) is complicated by the presence of isobaric phosphatidylcholine (PC) species, which generate a common m/z 184 product ion in the presence of ammonium ions as a result of the phosphocholine headgroup. Lithium ion adducts of SM undergo a selective dehydration [Li + H2O + (CH3)3NC2H4PO4] with a corresponding neutral loss of -207 Da. This neutral loss was employed to create a SM-selective method for identifying target species, which were quantitated using multiple reaction monitoring (MRM). SM-selective fragments in MS3 were used to characterize the sphingosine base and acyl chain. These methods were used to identify 50 individual SM species in bovine milk ranging from SM 28:1 to SM 44:2, with d16:1, d17:1, d18:1, d19:1, and d20:1 bases, and acyl fatty acids ranging from 10 to 25 carbons and 0-1 desaturations. Spiked SM standards into milk had a recovery of 99.7%, and endogenous milk SM had <10% coefficient of variation for both intra- and interday variability, with limits of detection of 1.4-5.55 nM and limits of quantitation of 11.8-178.1 nM. This MS-MRM method was employed to accurately and precisely quantify SM species in dairy products, including bovine-derived whole milk, half and half, whipping cream, and goat milk.


Assuntos
Compostos de Amônio , Esfingomielinas , Esfingomielinas/química , Lítio , Esfingosina , Fosforilcolina , Espectrometria de Massas/métodos , Fosfatidilcolinas/química , Íons , Ácidos Graxos
16.
Proc Natl Acad Sci U S A ; 119(43): e2206083119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36269859

RESUMO

Genome-wide association studies (GWASs) have identified genetic loci associated with the risk of Alzheimer's disease (AD), but the molecular mechanisms by which they confer risk are largely unknown. We conducted a metabolome-wide association study (MWAS) of AD-associated loci from GWASs using untargeted metabolic profiling (metabolomics) by ultraperformance liquid chromatography-mass spectrometry (UPLC-MS). We identified an association of lactosylceramides (LacCer) with AD-related single-nucleotide polymorphisms (SNPs) in ABCA7 (P = 5.0 × 10-5 to 1.3 × 10-44). We showed that plasma LacCer concentrations are associated with cognitive performance and genetically modified levels of LacCer are associated with AD risk. We then showed that concentrations of sphingomyelins, ceramides, and hexosylceramides were altered in brain tissue from Abca7 knockout mice, compared with wild type (WT) (P = 0.049-1.4 × 10-5), but not in a mouse model of amyloidosis. Furthermore, activation of microglia increases intracellular concentrations of hexosylceramides in part through induction in the expression of sphingosine kinase, an enzyme with a high control coefficient for sphingolipid and ceramide synthesis. Our work suggests that the risk for AD arising from functional variations in ABCA7 is mediated at least in part through ceramides. Modulation of their metabolism or downstream signaling may offer new therapeutic opportunities for AD.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Doença de Alzheimer , Ceramidas , Animais , Camundongos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Ceramidas/metabolismo , Cromatografia Líquida , Estudo de Associação Genômica Ampla , Lactosilceramidas , Metaboloma , Camundongos Knockout , Esfingomielinas , Espectrometria de Massas em Tandem
17.
Int J Mol Sci ; 23(19)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36232961

RESUMO

Male fertility, as manifest by the quantity and progressive motility of spermatozoa, is negatively impacted by obesity, dyslipidaemia and metabolic disease. However, the relative distribution of lipids in spermatozoa and the two compartments which supply lipids for spermatogenesis (seminal fluid and blood serum) has not been studied. We hypothesised that altered availability of lipids in blood serum and seminal fluid may affect the lipid composition and progressive motility of sperm. 60 men of age 35 years (median (range 20-45) and BMI 30.4 kg/m2 (24-36.5) under preliminary investigation for subfertility were recruited at an NHS clinic. Men provided samples of serum and semen, subject to strict acceptance criteria, for analysis of spermatozoa count and motility. Blood serum (n = 60), spermatozoa (n = 26) and seminal fluid (n = 60) were frozen for batch lipidomics analysis. Spermatozoa and seminal fluid had comparable lipid composition but showed marked differences with the serum lipidome. Spermatozoa demonstrated high abundance of ceramides, very-long-chain fatty acids (C20-22), and certain phospholipids (sphingomyelins, plasmalogens, phosphatidylethanolamines) with low abundance of phosphatidylcholines, cholesterol and triglycerides. Men with spermatozoa of low progressive motility had evidence of fewer concentration gradients for many lipid species between blood serum and spermatozoa compartments. Spermatozoa are abundant in multiple lipid species which are likely to contribute to key cellular functions. Lipid metabolism shows reduced regulation between compartments in men with spermatozoa with reduced progressive motility.


Assuntos
Sêmen , Motilidade Espermática , Adulto , Ceramidas/metabolismo , Colesterol/metabolismo , Ácidos Graxos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Plasmalogênios , Sêmen/metabolismo , Contagem de Espermatozoides , Motilidade Espermática/fisiologia , Espermatozoides/metabolismo , Esfingomielinas/metabolismo , Triglicerídeos/metabolismo , Adulto Jovem
18.
Int J Mol Sci ; 23(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36233252

RESUMO

Atherosclerosis-a systemic inflammatory disease-is the number one cause of mortality and morbidity worldwide. As such, the prevention of disease progression is of global interest in order to reduce annual deaths at a significant scale. Atherosclerosis is characterized by plaque formation in the arteries, resulting in vascular events such as ischemic stroke or myocardial infarction. A better understanding of the underlying pathophysiological processes at the cellular and molecular level is indispensable to identify novel therapeutic targets that may alleviate disease initiation or progression. Sphingolipids-a lipid class named after the chimeric creature sphinx-are considered to play a critical and, metaphorically, equally chimeric regulatory role in atherogenesis. Previous studies identified six common sphingolipids, namely dihydroceramide (DhCer), ceramide (Cer), sphingosine-1-phosphate (S1P), sphingomyelin (SM), lactosylceramide (LacCer), and glucosylceramide (GluCer) in carotid plaques, and demonstrated their potential as inducers of plaque inflammation. In this review, we point out their specific roles in atherosclerosis by focusing on different cell types, carrier molecules, enzymes, and receptors involved in atherogenesis. Whereas we assume mainly atheroprotective effects for GluCer and LacCer, the sphingolipids DhCer, Cer, SM and S1P mediate chimeric functions. Initial studies demonstrate the successful use of interventions in the sphingolipid pathway to prevent atherosclerosis. However, as atherosclerosis is a multifactorial disease with a variety of underlying cellular processes, it is imperative for future research to emphasize the circumstances in which sphingolipids exert protective or progressive functions and to evaluate their therapeutic benefits in a spatiotemporal manner.


Assuntos
Aterosclerose , Placa Aterosclerótica , Antígenos CD , Aterosclerose/genética , Ceramidas/metabolismo , Quimera/metabolismo , Glucosilceramidas , Humanos , Lactosilceramidas , Lisofosfolipídeos , Esfingolipídeos/metabolismo , Esfingomielinas/metabolismo , Esfingosina/análogos & derivados
19.
Commun Biol ; 5(1): 1074, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209301

RESUMO

Dysregulation of sphingomyelin and ceramide metabolism have been implicated in Alzheimer's disease. Genome-wide and transcriptome-wide association studies have identified various genes and genetic variants in lipid metabolism that are associated with Alzheimer's disease. However, the molecular mechanisms of sphingomyelin and ceramide disruption remain to be determined. We focus on the sphingolipid pathway and carry out multi-omics analyses to identify central and peripheral metabolic changes in Alzheimer's patients, correlating them to imaging features. Our multi-omics approach is based on (a) 2114 human post-mortem brain transcriptomics to identify differentially expressed genes; (b) in silico metabolic flux analysis on context-specific metabolic networks identified differential reaction fluxes; (c) multimodal neuroimaging analysis on 1576 participants to associate genetic variants in sphingomyelin pathway with Alzheimer's disease pathogenesis; (d) plasma metabolomic and lipidomic analysis to identify associations of lipid species with dysregulation in Alzheimer's; and (e) metabolite genome-wide association studies to define receptors within the pathway as a potential drug target. We validate our hypothesis in amyloidogenic APP/PS1 mice and show prolonged exposure to fingolimod alleviated synaptic plasticity and cognitive impairment in mice. Our integrative multi-omics approach identifies potential targets in the sphingomyelin pathway and suggests modulators of S1P metabolism as possible candidates for Alzheimer's disease treatment.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Ceramidas , Cloridrato de Fingolimode , Estudo de Associação Genômica Ampla , Humanos , Camundongos , Esfingolipídeos/metabolismo , Esfingolipídeos/uso terapêutico , Esfingomielinas/uso terapêutico
20.
Biochem Biophys Res Commun ; 632: 129-138, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36209581

RESUMO

Recently, with increasing awareness of health issues, non-alcoholic fatty liver disease (NAFLD) has become an epidemic attracting global attention. As a serious chronic disease, NAFLD is clinically managed with pharmacological interventions that are usually associated with poor long-term efficacy and adverse effects. In this scenario, traditional Chinese medicine (TCM) characterized by "multiple ingredients-multiple targets-multiple pathways" shows promise as a potential option to treat NAFLD. Zexie decoction (ZXD) is a classical TCM formula that possesses favorable lipid-lowering and anti-inflammatory activities. Accumulating evidence indicates that ZXD displays robust efficacy in treating NAFLD. The effectiveness of ZXD against NAFLD has been evaluated in our previous studies. This study further examines its probable mechanism of action in an in-depth manner using multi-omic analysis based on the gut-liver axis and sheds light on the potential relationship among genes, hepatic lipid metabolites, and gut microbiotas. Totally, 71 differentially expressed genes (34 upregulated and 37 downregulated genes), 31 differential lipid molecules (8 upregulated and 23 downregulated), and 56 differential gut microbiotas (37 upregulated and 19 downregulated) were identified in the ZXD-treated group rats compared with the negative control group rats. Of these, owing to their key role in the association analysis, g_Blautia, g_Romboutsia, and g_Lactobacillus were hypothesized to be crucial gut microbiotas in the ZXD-mediated treatment of NAFLD. These microbiotas were found to synergize with key genes, such as AKR1B8, CCN1, and TNKS2, and hepatic lipid metabolites, such as glycerophospholipid and sphingomyelin, which might play a therapeutic role by regulating fatty acid synthesis, correcting lipid metabolism disorder, or reducing the inflammatory response. Overall, the present study provides fresh insights into the ZXD-mediated treatment of NAFLD, which, in turn, is expected to give a push to the modernization of TCM.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Esfingomielinas/metabolismo , Fígado/metabolismo , Ácidos Graxos/metabolismo , Glicerofosfolipídeos/metabolismo , Glicerofosfolipídeos/farmacologia , Glicerofosfolipídeos/uso terapêutico , Dieta Hiperlipídica/efeitos adversos
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