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1.
Ageing Res Rev ; 97: 102294, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38583577

RESUMEN

Cellular senescence is a kind of cellular state triggered by endogenous or exogenous stimuli, which is mainly characterized by stable cell cycle arrest and complex senescence-associated secretory phenotype (SASP). Once senescent cells accumulate in tissues, they may eventually accelerate the progression of age-related diseases, such as atherosclerosis, osteoarthritis, chronic lung diseases, cancers, etc. Recent studies have shown that the disorders of lipid metabolism are not only related to age-related diseases, but also regulate the cellular senescence process. Based on existing research evidences, the changes in lipid metabolism in senescent cells are mainly concentrated in the metabolic processes of phospholipids, fatty acids and cholesterol. Obviously, the changes in lipid-metabolizing enzymes and proteins involved in these pathways play a critical role in senescence. However, the link between cellular senescence, changes in lipid metabolism and age-related disease remains to be elucidated. Herein, we summarize the lipid metabolism changes in senescent cells, especially the senescent cells that promote age-related diseases, as well as focusing on the role of lipid-related enzymes or proteins in senescence. Finally, we explore the prospect of lipids in cellular senescence and their potential as drug targets for preventing and delaying age-related diseases.


Asunto(s)
Envejecimiento , Senescencia Celular , Metabolismo de los Lípidos , Humanos , Senescencia Celular/fisiología , Metabolismo de los Lípidos/fisiología , Envejecimiento/metabolismo , Animales , Lípidos/fisiología
3.
Prostate ; 84(7): 644-655, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38409853

RESUMEN

BACKGROUND: Lipid reprogramming is a known mechanism to increase the energetic demands of proliferating cancer cells to drive and support tumorigenesis and progression. Elevated lipid droplets (LDs) are a well-known alteration of lipid reprogramming in many cancers, including prostate cancer (PCa), and are associated with high tumor aggressiveness as well as therapy resistance. The mechanism of LD accumulation and specific LD functions are still not well understood; however, it has been shown that LDs can form as a protective mechanism against lipotoxicity and lipid peroxidation in the cell. METHODS: This study investigated the significance of LDs in PCa. This was done by staining, imaging, image quantification, and flow cytometry analysis of LDs in PCa cells. Additionally, lipidomics and metabolomics experiments were performed to assess the difference of metabolites and lipids in control and treatment surviving cancer cells. Lastly, to assess clinical significance, multiple publicly available datasets were mined for LD-related data. RESULTS: Our study demonstrated that prostate and breast cancer cells that survive 72 h of chemotherapy treatment have elevated LDs. These LDs formed in tandem with elevated reactive oxygen species levels to sequester damaged and excess lipids created by oxidative stress, which promoted cell survival. Additionally, by inhibiting diacylglycerol O-acyltransferase 1 (DGAT1) (which catalyzes triglyceride synthesis into LDs) and treating with chemotherapy simultaneously, we were able to decrease the overall amount of LDs and increase cancer cell death compared to treating with chemotherapy alone. CONCLUSIONS: Overall, our study proposes a potential combination therapy of DGAT1 inhibitors and chemotherapy to increase cancer cell death.


Asunto(s)
Gotas Lipídicas , Neoplasias de la Próstata , Masculino , Humanos , Gotas Lipídicas/metabolismo , Gotas Lipídicas/patología , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Neoplasias de la Próstata/patología , Metabolismo de los Lípidos/fisiología , Lípidos/fisiología
4.
Mem Inst Oswaldo Cruz ; 118: e230044, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37820117

RESUMEN

Lipid droplets (LD) are evolutionarily conserved lipid-enriched organelles with a diverse array of cell- and stimulus-regulated proteins. Accumulating evidence demonstrates that intracellular pathogens exploit LD as energy sources, replication sites, and part of the mechanisms of immune evasion. Nevertheless, LD can also favor the host as part of the immune and inflammatory response to pathogens. The functions of LD in the central nervous system have gained great interest due to their presence in various cell types in the brain and for their suggested involvement in neurodevelopment and neurodegenerative diseases. Only recently have the roles of LD in neuroinfections begun to be explored. Recent findings reveal that lipid remodelling and increased LD biogenesis play important roles for Zika virus (ZIKV) replication and pathogenesis in neural cells. Moreover, blocking LD formation by targeting DGAT-1 in vivo inhibited virus replication and inflammation in the brain. Therefore, targeting lipid metabolism and LD biogenesis may represent potential strategies for anti-ZIKV treatment development. Here, we review the progress in understanding LD functions in the central nervous system in the context of the host response to Zika infection.


Asunto(s)
Infecciones del Sistema Nervioso Central , Gotas Lipídicas , Infección por el Virus Zika , Virus Zika , Humanos , Gotas Lipídicas/metabolismo , Gotas Lipídicas/fisiología , Gotas Lipídicas/virología , Lípidos/fisiología , Replicación Viral/fisiología , Virus Zika/fisiología , Infección por el Virus Zika/fisiopatología , Infección por el Virus Zika/virología , Infecciones del Sistema Nervioso Central/fisiopatología , Infecciones del Sistema Nervioso Central/virología
5.
Ocul Surf ; 29: 497-507, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37422152

RESUMEN

Meibomian glands (MGs) secrete lipid (meibum) onto the ocular surface to form the outermost layer of the tear film. Proper meibum secretion is essential for stabilizing the tear film, reducing aqueous tear evaporation, and maintaining the homeostasis of the ocular surface. Atrophy of MG as occurs with aging, leads to reduction of meibum secretion, loss of ocular surface homeostasis and evaporative dry eye disease (EDED). Since MGs are holocrine glands, secretion of meibum requires continuous self-renewal of lipid-secreting acinar meibocytes by stem/progenitor cells, whose proliferative potential is dramatically reduced with age leading to MG atrophy and an age-related meibomian gland dysfunction (ARMGD). Understanding the cellular and molecular mechanisms regulating meibocyte stem/progenitor cell maintenance and renewal may provide novel approaches to regenerating MG and treating EDED. Towards that end, recent label retaining cell and lineage-tracing experiments as well as knock-out transgenic mouse studies have begun to identify the location and identities of meibocyte progenitor cells and potential growth and transcription factors that may regulate meibocyte renewal. In addition, recent reports have shown that ARMGD may be reversed by novel therapeutics in mice. Herein, we discuss our current understanding of meibocyte stem/progenitor cells and the hunt for gland renewal.


Asunto(s)
Síndromes de Ojo Seco , Glándulas Tarsales , Animales , Ratones , Glándulas Tarsales/patología , Lágrimas/fisiología , Células Madre , Lípidos/fisiología , Atrofia/patología
6.
J Biol Chem ; 299(4): 103042, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36803964

RESUMEN

Hepatic stellate cells (HSCs) are liver-resident cells best known for their role in vitamin A storage under physiological conditions. Upon liver injury, HSCs activate into myofibroblast-like cells, a key process in the onset of liver fibrosis. Lipids play an important role during HSC activation. Here, we provide a comprehensive characterization of the lipidomes of primary rat HSCs during 17 days of activation in vitro. For lipidomic data interpretation, we expanded our previously described Lipid Ontology (LION) and associated web application (LION/Web) with the LION-PCA heatmap module, which generates heatmaps of the most typical LION-signatures in lipidomic datasets. Furthermore, we used LION to perform pathway analysis to determine the significant metabolic conversions in lipid pathways. Together, we identify two distinct stages of HSC activation. In the first stage, we observe a decrease of saturated phosphatidylcholine, sphingomyelin, and phosphatidic acid and an increase in phosphatidylserine and polyunsaturated bis(monoacylglycero)phosphate (BMP), a lipid class typically localized at endosomes and lysosomes. In the second activation stage, BMPs, hexosylceramides, and ether-linked phosphatidylcholines are elevated, resembling a lysosomal lipid storage disease profile. The presence of isomeric structures of BMP in HSCs was confirmed ex vivo in MS-imaging datasets of steatosed liver sections. Finally, treatment with pharmaceuticals targeting the lysosomal integrity led to cell death in primary HSCs but not in HeLa cells. In summary, our combined data suggest that lysosomes play a critical role during a two-stage activation process of HSCs.


Asunto(s)
Células Estrelladas Hepáticas , Lipidómica , Humanos , Ratas , Animales , Células Estrelladas Hepáticas/metabolismo , Células HeLa , Cirrosis Hepática/metabolismo , Lisosomas/metabolismo , Lípidos/fisiología
7.
Cells ; 11(24)2022 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-36552752

RESUMEN

The roles of lamin A/C in adipocyte differentiation and skeletal muscle lipid metabolism are associated with familial partial lipodystrophy of Dunnigan (FPLD). We confirmed that LMNA knockdown (KD) in mouse adipose-derived mesenchymal stem cells (AD-MSCs) prevented adipocyte maturation. Importantly, in in vitro experiments, we discovered a significant increase in phosphorylated lamin A/C levels at serine 22 or 392 sites (pLamin A/C-S22/392) accompanying increased lipid synthesis in a liver cell line (7701 cells) and two hepatocellular carcinoma (HCC) cell lines (HepG2 and MHCC97-H cells). Moreover, HCC cells did not survive after LMNA knockout (KO) or even KD. Evidently, the functions of lamin A/C differ between the liver and adipose tissue. To date, the mechanism of hepatocyte lipid metabolism mediated by nuclear lamin A/C remains unclear. Our in-depth study aimed to identify the molecular connection between lamin A/C and pLamin A/C, hepatic lipid metabolism and liver cancer. Gain- and loss-of-function experiments were performed to investigate functional changes and the related molecular pathways in 7701 cells. Adenosine 5' monophosphate-activated protein kinase α (AMPKα) was activated when abnormalities in functional lamin A/C were observed following lamin A/C depletion or farnesyltransferase inhibitor (FTI) treatment. Active AMPKα directly phosphorylated acetyl-CoA-carboxylase 1 (ACC1) and subsequently inhibited lipid synthesis but induced glycolysis in both HCC cells and normal cells. According to the mass spectrometry analysis, lamin A/C potentially regulated AMPKα activation through its chaperone proteins, ATPase or ADP/ATP transporter 2. Lonafarnib (an FTI) combined with low-glucose conditions significantly decreased the proliferation of the two HCC cell lines more efficiently than lonafarnib alone by inhibiting glycolysis or the maturation of prelamin A.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Carcinoma Hepatocelular , Lamina Tipo A , Neoplasias Hepáticas , Animales , Ratones , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Homeostasis , Lamina Tipo A/genética , Lamina Tipo A/metabolismo , Lípidos/fisiología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo
8.
Int J Mol Sci ; 23(20)2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36293388

RESUMEN

For rapid and unlimited cell growth and proliferation, cancer cells require large quantities of nutrients. Many metabolic pathways and nutrient uptake systems are frequently reprogrammed and upregulated to meet the demand from cancer cells, including the demand for lipids. The lipids for most adult normal cells are mainly acquired from the circulatory system. Whether different cancer cells adopt identical mechanisms to ensure sufficient lipid supply, and whether the lipid demand and supply meet each other, remains unclear, and was investigated in lung cancer cells. Results showed that, despite frequent upregulation in de novo lipogenesis and the lipid transporter system, different lung cancer cells adopt different proteins to acquire sufficient lipids, and the lipid supply frequently exceeds the demand, as significant amounts of lipids stored in the lipid droplets could be found within lung cancer cells. Lipid droplet surface protein, PLIN3, was found frequently overexpressed since the early stage in lung cancer tissues. Although the expression is not significantly associated with a specific gender, age, histology type, disease stage, and smoking habit, the frequently elevated expression of PLIN3 protein indicates the importance of lipid droplets for lung cancer. These lipid droplets are not only for nutrient storage, but are also crucial for tumor growth and proliferation, as well as survival in starvation. These results suggest that manipulation of lipid droplet formation or TG storage in lung cancer cells could potentially decrease the progression of lung cancer. Further exploration of lipid biology in lung cancer could help design novel treatment strategies.


Asunto(s)
Neoplasias Pulmonares , Inanición , Adulto , Humanos , Gotas Lipídicas/metabolismo , Perilipina-3/metabolismo , Metabolismo de los Lípidos , Proliferación Celular , Proteínas de la Membrana/metabolismo , Inanición/metabolismo , Neoplasias Pulmonares/metabolismo , Lípidos/fisiología
9.
Cells ; 11(15)2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35954186

RESUMEN

The simultaneous occurrence of heat stress and drought is becoming more regular as a consequence of climate change, causing extensive agricultural losses. The application of either heat or osmotic stress increase cell-wall suberization in different tissues, which may play a role in improving plant resilience. In this work, we studied how the suberization process is affected by the combination of drought and heat stress by following the expression of suberin biosynthesis genes, cell-wall suberization and the chemical composition in Arabidopsis roots. The Arabidopsis plants used in this study were at the onset of secondary root development. At this point, one can observe a developmental gradient in the main root, with primary development closer to the root tip and secondary development, confirmed by the suberized phellem, closer to the shoot. Remarkably, we found a differential response depending on the root zone. The combination of drought and heat stress increased cell wall suberization in main root segments undergoing secondary development and in lateral roots (LRs), while the main root zone, at primary development stage, was not particularly affected. We also found differences in the overall chemical composition of the cell walls in both root zones in response to combined stress. The data gathered showed that, under combined drought and heat stress, Arabidopsis roots undergo differential cell wall remodeling depending on developmental stage, with modifications in the biosynthesis and/or assembly of major cell wall components.


Asunto(s)
Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Pared Celular/metabolismo , Lípidos/fisiología , Presión Osmótica/fisiología , Raíces de Plantas/metabolismo , Plantas
10.
J Invertebr Pathol ; 193: 107799, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35850258

RESUMEN

Phurealipids (Photorhabdus urea lipids) are synthesized from Photorhabdus bacteria that are symbiotic to entomopathogenic nematodes. Their chemical structures are similar to that of juvenile hormone (JH) and have been suspected to mimic JH signaling in immunity and the development of insects. This study investigated the physiological roles of phurealipids with respect to their contribution to bacterial pathogenicity using four natural (HB13, HB69, HB416, and HB421) and one derivative (HB27) compound. First, phurealipids like JH suppressed insect immune responses. Overall, phurealipids showed JH like immunosuppressive behavior in a lepidopteran insect Spodoptera exigua larvae. More specifically, phurealipids significantly suppressed the hemocyte spreading behavior which is a key immune response upon immune challenge. Interestingly, the methyl urea derivatives (HB13, HB27, and HB69) were more potent than the unmethylated forms (HB416 and HB421). The inhibitory activity of phurealipids prevented the cellular immune response measured by hemocytic nodule formation in response to the bacterial challenge. Phurealipids also suppressed the expression of cecropin and gallerimycin, which are two highly inducible antimicrobial peptides, in S. exigua upon immune challenge. The immunosuppressive activity of the phurealipids significantly enhanced the bacterial pathogenicity of Bacillus thuringiensis against S. exigua. Second, phurealipids like JH prevented insect metamorphosis. Especially, the methylated urea derivatives of the phurealipids showed the JH-like function by inducing the expression of S. exigua Kr-h1, a transcriptional factor. At the pupal stage, exhibiting the lowest expression of Kr-h1, phurealipid treatments elevated the expression level of Kr-h1 and delayed the pupa-to-adult metamorphosis. These results suggest that phurealipids play crucial roles in Photorhabdus pathogenicity by suppressing host immune defenses and delaying host metamorphosis.


Asunto(s)
Hormonas Juveniles , Lípidos , Photorhabdus , Animales , Proteínas de Insectos/metabolismo , Insectos , Larva/microbiología , Metabolismo de los Lípidos , Lípidos/fisiología , Photorhabdus/metabolismo , Pupa , Urea/metabolismo
11.
Ann N Y Acad Sci ; 1511(1): 87-106, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35218041

RESUMEN

Recent research has shed light on the cellular and molecular functions of bioactive lipids that go far beyond what was known about their role as dietary lipids. Bioactive lipids regulate inflammation and its resolution as signaling molecules. Genetic studies have identified key factors that can increase the risk of cardiovascular diseases and metabolic syndrome through their effects on lipogenesis. Lipid scientists have explored how these signaling pathways affect lipid metabolism in the liver, adipose tissue, and macrophages by utilizing a variety of techniques in both humans and animal models, including novel lipidomics approaches and molecular dynamics models. Dissecting out these lipid pathways can help identify mechanisms that can be targeted to prevent or treat cardiometabolic conditions. Continued investigation of the multitude of functions mediated by bioactive lipids may reveal additional components of these pathways that can provide a greater understanding of metabolic homeostasis.


Asunto(s)
Síndrome Metabólico , Animales , Grasas de la Dieta , Homeostasis/fisiología , Humanos , Metabolismo de los Lípidos/fisiología , Lípidos/fisiología , Síndrome Metabólico/metabolismo
12.
Int J Mol Sci ; 23(3)2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35163232

RESUMEN

Despite all the advances of modern medicine, atherosclerosis continues to be one of the most important medical and social problems. Atherosclerosis is the cause of several cardiovascular diseases, which are associated with high rates of disability and mortality. The development of atherosclerosis is associated with the accumulation of lipids in the arterial intima and the disruption of mechanisms that maintain the balance between the development and resolution of inflammation. Fatty acids are involved in many mechanisms of inflammation development and maintenance. Endothelial cells demonstrate multiple cross-linkages between lipid metabolism and innate immunity. In addition, these processes are linked to hemodynamics and the function of other cells in the vascular wall, highlighting the central role of the endothelium in vascular biology.


Asunto(s)
Aterosclerosis/inmunología , Aterosclerosis/metabolismo , Ácidos Grasos/metabolismo , Animales , Enfermedades Cardiovasculares/metabolismo , Eicosanoides/metabolismo , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Ácidos Grasos/inmunología , Hemodinámica , Humanos , Inmunidad Innata , Inflamación/inmunología , Inflamación/metabolismo , Metabolismo de los Lípidos/inmunología , Metabolismo de los Lípidos/fisiología , Lípidos/fisiología , Túnica Íntima/metabolismo
13.
Int J Mol Sci ; 23(4)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35216234

RESUMEN

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease in which dry and itchy skin may develop into skin lesions. AD has a strong genetic component, as children from parents with AD have a two-fold increased chance of developing the disease. Genetic risk loci and epigenetic modifications reported in AD mainly locate to genes involved in the immune response and epidermal barrier function. However, AD pathogenesis cannot be fully explained by (epi)genetic factors since environmental triggers such as stress, pollution, microbiota, climate, and allergens also play a crucial role. Alterations of the epidermal barrier in AD, observed at all stages of the disease and which precede the development of overt skin inflammation, manifest as: dry skin; epidermal ultrastructural abnormalities, notably anomalies of the lamellar body cargo system; and abnormal epidermal lipid composition, including shorter fatty acid moieties in several lipid classes, such as ceramides and free fatty acids. Thus, a compelling question is whether AD is primarily a lipid disorder evolving into a chronic inflammatory disease due to genetic susceptibility loci in immunogenic genes. In this review, we focus on lipid abnormalities observed in the epidermis and blood of AD patients and evaluate their primary role in eliciting an inflammatory response.


Asunto(s)
Dermatitis Atópica/metabolismo , Grasas/metabolismo , Animales , Epidermis/metabolismo , Humanos , Inflamación/metabolismo , Lípidos/fisiología
14.
Int J Mol Sci ; 23(4)2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35216253

RESUMEN

In recent years, several studies have demonstrated that polyunsaturated fatty acids have strong immunomodulatory properties, altering several functions of macrophages. In the present work, we sought to provide a multi-omic approach combining the analysis of the lipidome, the proteome, and the metabolome of RAW 264.7 macrophages supplemented with phospholipids containing omega-3 (PC 18:0/22:6; ω3-PC) or omega-6 (PC 18:0/20:4; ω6-PC) fatty acids, alone and in the presence of lipopolysaccharide (LPS). Supplementation of macrophages with ω3 and ω6 phospholipids plus LPS produced a significant reprogramming of the proteome of macrophages and amplified the immune response; it also promoted the expression of anti-inflammatory proteins (e.g., pleckstrin). Supplementation with the ω3-PC and ω6-PC induced significant changes in the lipidome, with a marked increase in lipid species linked to the inflammatory response, attributed to several pro-inflammatory signalling pathways (e.g., LPCs) but also to the pro-resolving effect of inflammation (e.g., PIs). Finally, the metabolomic analysis demonstrated that supplementation with ω3-PC and ω6-PC induced the expression of several metabolites with a pronounced inflammatory and anti-inflammatory effect (e.g., succinate). Overall, our data show that supplementation of macrophages with ω3-PC and ω6-PC effectively modulates the lipidome, proteome, and metabolome of these immune cells, affecting several metabolic pathways involved in the immune response that are triggered by inflammation.


Asunto(s)
Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-6/metabolismo , Factores Inmunológicos/metabolismo , Lípidos/fisiología , Macrófagos/metabolismo , Fosfolípidos/metabolismo , Proteínas/metabolismo , Animales , Inmunidad/fisiología , Inflamación/metabolismo , Lipidómica/métodos , Metaboloma/fisiología , Ratones , Proteoma/metabolismo , Células RAW 264.7 , Transducción de Señal/fisiología
15.
Int J Mol Sci ; 23(4)2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35216410

RESUMEN

Alzheimer's disease (AD) is characterized by an increased plaque burden and tangle accumulation in the brain accompanied by extensive lipid alterations. Methylxanthines (MTXs) are alkaloids frequently consumed by dietary intake known to interfere with the molecular mechanisms leading to AD. Besides the fact that MTX consumption is associated with changes in triglycerides and cholesterol in serum and liver, little is known about the effect of MTXs on other lipid classes, which raises the question of whether MTX can alter lipids in a way that may be relevant in AD. Here we have analyzed naturally occurring MTXs caffeine, theobromine, theophylline, and the synthetic MTXs pentoxifylline and propentofylline also used as drugs in different neuroblastoma cell lines. Our results show that lipid alterations are not limited to triglycerides and cholesterol in the liver and serum, but also include changes in sphingomyelins, ceramides, phosphatidylcholine, and plasmalogens in neuroblastoma cells. These changes comprise alterations known to be beneficial, but also adverse effects regarding AD were observed. Our results give an additional perspective of the complex link between MTX and AD, and suggest combining MTX with a lipid-altering diet compensating the adverse effects of MTX rather than using MTX alone to prevent or treat AD.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Lípidos/fisiología , Neuroblastoma/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Xantinas/farmacología , Cafeína/farmacología , Línea Celular Tumoral , Colesterol/metabolismo , Humanos , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/metabolismo , Pentoxifilina/farmacología , Teobromina/farmacología , Teofilina/farmacología , Triglicéridos/metabolismo
16.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35042820

RESUMEN

RNA is a ubiquitous biomolecule that can serve as both catalyst and information carrier. Understanding how RNA bioactivity is controlled is crucial for elucidating its physiological roles and potential applications in synthetic biology. Here, we show that lipid membranes can act as RNA organization platforms, introducing a mechanism for riboregulation. The activity of R3C ribozyme can be modified by the presence of lipid membranes, with direct RNA-lipid interactions dependent on RNA nucleotide content, base pairing, and length. In particular, the presence of guanine in short RNAs is crucial for RNA-lipid interactions, and G-quadruplex formation further promotes lipid binding. Lastly, by artificially modifying the R3C substrate sequence to enhance membrane binding, we generated a lipid-sensitive ribozyme reaction with riboswitch-like behavior. These findings introduce RNA-lipid interactions as a tool for developing synthetic riboswitches and RNA-based lipid biosensors and bear significant implications for RNA world scenarios for the origin of life.


Asunto(s)
Lípidos/fisiología , Lípidos de la Membrana/metabolismo , ARN/metabolismo , Emparejamiento Base/genética , Secuencia de Bases/genética , Sitios de Unión/genética , Membrana Celular/metabolismo , Membrana Celular/fisiología , Ingeniería Genética/métodos , Metabolismo de los Lípidos/fisiología , Lípidos/genética , Lípidos de la Membrana/fisiología , Conformación de Ácido Nucleico , ARN/química , ARN Catalítico/química , ARN Catalítico/metabolismo , Riboswitch/genética
17.
PLoS One ; 17(1): e0261446, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34986194

RESUMEN

AIM: To study the possible effects of a dietary intervention with minimal and unprocessed foods, high in natural saturated fats on the lipid profile and body mass index of children. METHOD: This study combines three intervention studies; one non-randomized retrospective cohort study and two randomized controlled trials, to a pooled analysis. The intervention group received a dietary intervention of minimal and unprocessed foods for three to six months, consisting of five times per week green vegetables, three times per week beef, daily 200-300 mL whole cow's milk (3.4% fat) and whole dairy butter (80% fat) on each slice of bread. The control group continued their usual dietary habits. Raw data of the three intervention studies where combined into one single dataset for data analysis, using mixed effects analysis of covariance to test the effects of the dietary advice on the main study outcomes, which are measurements of the lipid profile. RESULTS: In total, 267 children aged 1 to 16 years were followed. 135 children were included in the intervention group and 139 children in the control group. Characteristics (age, gender and follow-up period) were equally distributed between the groups at baseline. In the intervention group HDL-cholesterol increased significantly from 1.22 mmol/L, 95% confidence interval (CI) 1.14-1.32 to 1.42 mmol/L 95% CI 1.30-1.65 (p = 0.007). The increase over time in HDL cholesterol in the intervention group was significantly different compared to the increase in the control group (from 1.26 mmol/L, 95% CI 1.19-1.35, to 1.30 mmol/L, 95% CI 1.26-1.37) (p = 0.04). Due to the increased HDL concentration in the intervention group, the total cholesterol/HDL cholesterol ratio decreased significantly from 3.70 mmol/L, 95% CI 3.38-3.87, to 3.25 mmol/L, 95% CI 2.96-3.31 (p = 0.05). CONCLUSION: Consumption of minimal and unprocessed foods (high in natural saturated fats) has favourable effects on HDL cholesterol in children. Therefore, this dietary advice can safely be recommended to children.


Asunto(s)
HDL-Colesterol/metabolismo , Dietoterapia/métodos , Grasas de la Dieta/efectos adversos , Adolescente , Índice de Masa Corporal , Niño , Preescolar , LDL-Colesterol/metabolismo , Estudios de Cohortes , Dieta/efectos adversos , Dietoterapia/psicología , Ingestión de Energía , Ácidos Grasos , Conducta Alimentaria , Femenino , Humanos , Lactante , Metabolismo de los Lípidos/fisiología , Lipidómica/métodos , Lípidos/fisiología , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos
18.
Cell Rep ; 38(2): 110213, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-35021082

RESUMEN

Deficiency of the endoplasmic reticulum (ER) protein seipin results in generalized lipodystrophy by incompletely understood mechanisms. Here, we report mitochondrial abnormalities in seipin-deficient patient cells. A subset of seipin is enriched at ER-mitochondria contact sites (MAMs) in human and mouse cells and localizes in the vicinity of calcium regulators SERCA2, IP3R, and VDAC. Seipin association with MAM calcium regulators is stimulated by fasting-like stimuli, while seipin association with lipid droplets is promoted by lipid loading. Acute seipin removal does not alter ER calcium stores but leads to defective mitochondrial calcium import accompanied by a widespread reduction in Krebs cycle metabolites and ATP levels. In mice, inducible seipin deletion leads to mitochondrial dysfunctions preceding the development of metabolic complications. Together, these data suggest that seipin controls mitochondrial energy metabolism by regulating mitochondrial calcium influx at MAMs. In seipin-deficient adipose tissue, reduced ATP production compromises adipocyte properties, contributing to lipodystrophy pathogenesis.


Asunto(s)
Adipocitos/metabolismo , Subunidades gamma de la Proteína de Unión al GTP/metabolismo , Mitocondrias/metabolismo , Tejido Adiposo/metabolismo , Animales , Calcio/metabolismo , Línea Celular , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico , Metabolismo Energético/fisiología , Subunidades gamma de la Proteína de Unión al GTP/deficiencia , Subunidades gamma de la Proteína de Unión al GTP/fisiología , Humanos , Gotas Lipídicas/metabolismo , Metabolismo de los Lípidos/fisiología , Lípidos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL
19.
Cell Rep ; 38(2): 110206, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-35021096

RESUMEN

Mitochondria are known as the powerhouse of the cell. Dysfunction of mitochondria homeostasis induces the mitochondrial unfolded protein response (UPRmt), altering cellular metabolism. How cells sense the UPRmt to rewire metabolism is largely unknown. Here, we show that inactivation of either the citric/tricarboxylic acid (TCA) cycle enzymes aco-2 or idha-1, which encode aconitase and isocitrate dehydrogenase respectively, leads to citrate accumulation. In Caenorhabditis elegans, both in vitro and in vivo, citrate accumulation consequently triggers the UPRmt and also promotes lipid accumulation. The transcription factor DVE-1 binds to the promoter of the nuclear hormone receptor nhr-80 to transactivate its expression. NHR-80 then upregulates lipogenesis and lipid accumulation, shifting excess citrate for use in lipogenesis and for storage as triacylglycerol in lipid droplets. Inactivation of DVE-1 or NHR-80 fully abolishes the citrate-induced lipid accumulation. Therefore, our work uncovers a DVE-1-NHR-80-lipogenesis axis linking the transmission of the mitochondrial stress signal to lipid metabolism.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Ácido Cítrico/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Respuesta de Proteína Desplegada/fisiología , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/fisiología , Expresión Génica/genética , Regulación de la Expresión Génica/genética , Homeostasis , Metabolismo de los Lípidos/fisiología , Lípidos/fisiología , Mitocondrias/metabolismo , Receptores Citoplasmáticos y Nucleares/fisiología , Transducción de Señal , Factores de Transcripción/metabolismo
20.
Pflugers Arch ; 474(2): 231-242, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34797426

RESUMEN

The distribution of atherosclerotic lesions in the aorta and its branches of ApoE knockout (ApoE-/-) mice is like that of patients with atherosclerosis. By using high-resolution MALDI mass spectrometry imaging (MSI), we aimed at characterizing universally applicable physiological biomarkers by comparing the murine lipid marker profile with that of human atherosclerotic arteries. Therefore, the aorta or carotid artery of male ApoE-/- mice at different ages, human arteries with documented atherosclerotic changes originated from amputated limbs, and corresponding controls were analysed. Obtained data were subjected to multivariate statistical analysis to identify potential biomarkers. Thirty-one m/z values corresponding to individual lipid species of cholesterol esters, lysophosphatidylcholines, lysophosphatidylethanolamines, and cholesterol derivatives were found to be specific in aortic atherosclerotic plaques of old ApoE-/- mice. The lipid composition at related vessel positions of young ApoE-/- mice was more comparable with wild-type mice. Twenty-six m/z values of the murine lipid markers were found in human atherosclerotic peripheral arteries but also control vessels and showed a more patient-dependent diverse distribution. Extensive data analysis without marker preselection based on mouse data revealed lysophosphatidylcholine and glucosylated cholesterol species, the latter not being detected in the murine atherosclerotic tissue, as specific potential novel human atherosclerotic vessel markers. Despite the heterogeneous lipid profile of atherosclerotic peripheral arteries derived from human patients, we identified lipids specifically colocalized to atherosclerotic human tissue and plaques in ApoE-/- mice. These data highlight species-dependent differences in lipid profiles between peripheral artery disease and aortic atherosclerosis.


Asunto(s)
Lípidos/fisiología , Placa Aterosclerótica/metabolismo , Animales , Aorta/metabolismo , Enfermedades de la Aorta/metabolismo , Apolipoproteínas E/metabolismo , Aterosclerosis/metabolismo , Colesterol/metabolismo , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
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