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1.
Food Chem ; 398: 133834, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35961174

RESUMO

Insoluble dietary fibre from citrus peels (CIDF) was found to have adsorption and inhibitory effect on the activity of pancreatic lipase (PL). CIDF-400 exhibited the greatest adsorption and activity inhibition effect on PL. The fluorescence quenching spectra indicated that CIDF could quench PL through a dynamic quenching process induced by the electrostatic interactions with only one binding site between them. The synchronous fluorescence and three-dimensional fluorescence spectra showed that CIDF might combine with PL to induce the increase in hydrophobicity and the reduction in polarity of tyrosine (Tyr) and tryptophan (Try) residues, which further led to the conformational alternations of PL. Moreover, circular dichroism (CD) showed that CIDF altered the secondary structure of PL, decreased α-helical structure content, and increased ß-sheet structure content, potentially resulting in PL structure opening and its active site exposure. This study provides new perspectives for the application of CIDFs produced from agricultural waste in regulating lipid metabolism.


Assuntos
Citrus , Lipase , Adsorção , Dicroísmo Circular , Citrus/química , Fibras na Dieta , Lipase/metabolismo , Pâncreas/metabolismo
2.
Food Chem ; 399: 133949, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35998496

RESUMO

This study demonstrated that solvent-free gas bubbling system enhanced production efficiency of pyridoxine monolaurate in the esterification catalyzed by immobilized Candida antarctica lipase B (Lipozyme 435). Volumetric productivity in solvent-free gas bubbling system (41.24 mmol/L/h) was 3.7 and 2.1-fold higher than those in conventional organic solvent system (11.10 mmol/L/h) and solvent-free system (19.86 mmol/L/h) using magnetic stirring, respectively. Among the three bioreactor systems, solvent-free gas bubbling system provided the best reusability of the lipase retaining 94.45 % of initial activity for six batch reactions. In the bioreactor system, 5-O-lauroyl-pyridoxine was regioselectively produced with maximum production of 371.17 mmol/L at 70 °C and 0.10 of substrate molar ratio ([pyridoxine]/[lauric acid]) for 9 h. Pyridoxine monolaurate exhibited interfacial activity at oil-water interfaces, suggesting it had emulsifying properties. Pyridoxine monolaurate is expected to be applied as a multi-functional emulsifier with nutritional values to replace both small molecule emulsifiers and pyridoxine hydrochloride in fortified beverages.


Assuntos
Enzimas Imobilizadas , Piridoxina , Reatores Biológicos , Catálise , Enzimas Imobilizadas/química , Esterificação , Lipase/metabolismo , Solventes/química
3.
Methods Mol Biol ; 2576: 299-305, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152197

RESUMO

The α,ß-hydrolase fold-containing protein 2 (ABHD2) is a serine hydrolase, responsible for the cleavage of endogenous 2-arachidonoylglycerol (2-AG). ABHD2 is activated by progesterone, thus, it is considered a nonnuclear receptor of this steroid hormone that terminates its biological effects. The products of ABHD2-catalyzed cleavage by the natural substrate 2-AG are glycerol and arachidonic acid; here, instead of 2-AG, the radioactive substrate 2-oleoyl-[3H]glycerol has been used as already done in various acylglycerol lipase activity assays. The amount of [3H]glycerol released allows to measure ABHD2 enzymatic activity.


Assuntos
Ácidos Araquidônicos , Glicerídeos , Ácido Araquidônico , Ácidos Araquidônicos/metabolismo , Endocanabinoides , Glicerídeos/metabolismo , Glicerol , Lipase/metabolismo , Progesterona , Serina
4.
Methods Mol Biol ; 2555: 181-194, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36306087

RESUMO

The discovery of new enzymes is strongly enabled by the implementation of high-throughput screening methods to detect enzymatic activity in single organisms or clone expression libraries, or to benchmark their performances against known prototypes. In this chapter, a number of methods, applicable at high-throughput scale, are described that allow the screening and characterization of enzymes relevant to biotechnology, particularly, ester-hydrolases (esterases, lipases, phospholipases, and polyester hydrolases).


Assuntos
Esterases , Lipase , Esterases/metabolismo , Lipase/metabolismo , Fosfolipases , Ensaios de Triagem em Larga Escala/métodos
5.
Food Chem ; 404(Pt B): 134710, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36323042

RESUMO

The bioconversion of onion extracts with P. acidilactici MNL5 enhances the metabolites and has a synergistic lipid-reduction impact that is beneficial for anti-obesity studies. The 48 h fermented onion extracts (FOE) demonstrated an enhanced inhibitory activity against pancreatic lipase (89.5 ± 1.25 %) as compared to the raw onion extract (ROE) (33.4 ± 0.86 %). The antioxidant properties of FOE significantly increased compared to the ROE inhibitory effect on DPPH (99.5 ± 2.40 mg vitamin C equiv./mg, DW FOE), and ABTS (104.5 ± 2.32 mg vitamin C equiv./mg, DW FOE). Based on FOE's higher antioxidant activity, UHPLC-Q-TOF-MS/MS demonstrated dramatic changes in the untargeted metabolite profile as compared to ROE. Moreover, C. elegans supplemented with FOE and quercetin exhibited an enhanced lifespan activity, lipid reduction, and decreased triglycerides. FOE can lower cholesterol and enhance quercetin to promote pancreatic lipase activity for synergistic anti-obesity effects.


Assuntos
Cebolas , Quercetina , Animais , Cebolas/metabolismo , Caenorhabditis elegans , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Lipase/metabolismo , Ácido Ascórbico/metabolismo , Lipídeos
6.
Arch Microbiol ; 204(12): 705, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36374350

RESUMO

Industrial important proteases and lipases are in increasing demand for various biotechnological applications. In the present study, the concomitantly produced protease and lipase by Haloferax sp. strain GUBF 2 were simultaneously purified as a heterogeneous lipase (45 and 66 kDa) and homogeneous protease (180 kDa); with 28.3 and 31.36 fold purity, respectively using Sephadex G-200. The aforementioned extremozymes were active at pH 3-13, 20-80 °C, 1-5 M NaCl, with optimal activity at pH 6, 70 °C, and 3 M NaCl, thus exhibiting attributes of true haloextremozymes. The Km and Vmax of purified lipase were 3.47 mM and 16.2 U/mL, while protease were 3.29 mg/mL and 28.5 U/mL, respectively. FTIR bands corresponding to the vibrations of amide II and amide III were detected in haloextremozymes which could perhaps be used to determine the secondary structure of the purified proteins. Furthermore, the activity of both enzymes was stimulated by Ca2+ and inhibited by 10 mM Hg2+ and phenylmethyl sulphonyl fluoride (PMSF). Additionally, these haloextremozymes are stable in the presence of detergent additives and organic solvents. In addition, purified protease displayed 74.3 ± 4.85% in-vitro blood clot dissolution activity. Conclusively this study revealed the key features, unusual properties, and possible biomedical applications of detergent-stable and organic solvent-tolerant haloextremozymes from Haloferax sp. strain GUBF 2 to date unexplored.


Assuntos
Haloferax , Lipase , Lipase/metabolismo , Solventes/química , Peptídeo Hidrolases/metabolismo , Detergentes/farmacologia , Detergentes/química , Estabilidade Enzimática , Haloferax/metabolismo , Cloreto de Sódio , Endopeptidases/metabolismo , Amidas , Concentração de Íons de Hidrogênio , Temperatura
7.
Int J Mol Sci ; 23(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36361599

RESUMO

Lipase B from Candida antarctica (CALB) and lipase from Thermomyces lanuginosus (TLL) were immobilized on octyl agarose. Then, the biocatalysts were chemically modified using glutaraldehyde, trinitrobenzenesulfonic acid or ethylenediamine and carbodiimide, or physically coated with ionic polymers, such as polyethylenimine (PEI) and dextran sulfate. These produced alterations of the enzyme activities have, in most cases, negative effects with some substrates and positive with other ones (e.g., amination of immobilized TLL increases the activity versus p-nitro phenyl butyrate (p-NPB), reduces the activity with R-methyl mandate by half and maintains the activity with S-isomer). The modification with PEI increased the biocatalyst activity 8-fold versus R-methyl mandelate. Enzyme stability was also modified, usually showing an improvement (e.g., the modification of immobilized TLL with PEI or glutaraldehyde enabled to maintain more than 70% of the initial activity, while the unmodified enzyme maintained less than 50%). The immobilized enzymes were also mineralized by using phosphate metals (Zn2+, Co2+, Cu2+, Ni2+ or Mg2+), and this affected also the enzyme activity, specificity (e.g., immobilized TLL increased its activity after zinc mineralization versus triacetin, while decreased its activity versus all the other assayed substrates) and stability (e.g., the same modification increase the residual stability from almost 0 to more than 60%). Depending on the enzyme, a metal could be positively, neutrally or negatively affected for a specific feature. Finally, we analyzed if the chemical modification could, somehow, tune the effects of the mineralization. Effectively, the same mineralization could have very different effects on the same immobilized enzyme if it was previously submitted to different physicochemical modifications. The same mineralization could present different effects on the enzyme activity, specificity or stability, depending on the previous modification performed on the enzyme, showing that these previous enzyme modifications alter the effects of the mineralization on enzyme features. For example, TLL modified with glutaraldehyde and treated with zinc salts increased its activity using R-methyl mandelate, while almost maintaining its activity versus the other unaltered substrates, whereas the aminated TLL maintained its activity with both methyl mandelate isomers, while it decreased with p-NPB and triacetin. TLL was found to be easier to tune than CALB by the strategies used in this paper. In this way, the combination of chemical or physical modifications of enzymes before their mineralization increases the range of modification of features that the immobilized enzyme can experienced, enabling to enlarge the biocatalyst library.


Assuntos
Enzimas Imobilizadas , Triacetina , Enzimas Imobilizadas/metabolismo , Glutaral , Lipase/metabolismo , Estabilidade Enzimática , Polietilenoimina , Zinco , Proteínas Fúngicas/metabolismo
8.
Int J Mol Sci ; 23(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36430745

RESUMO

Lipase B from Candida antarctica was immobilized on heterofunctional support octyl agarose activated with vinyl sulfone to prevent enzyme release under drastic conditions. Covalent attachment was established, but the blocking step using hexylamine, ethylenediamine or the amino acids glycine (Gly) and aspartic acid (Asp) altered the results. The activities were lower than those observed using the octyl biocatalyst, except when using ethylenediamine as blocking reagent and p-nitrophenol butyrate (pNPB) as substrate. The enzyme stability increased using these new biocatalysts at pH 7 and 9 using all blocking agents (much more significantly at pH 9), while it decreased at pH 5 except when using Gly as blocking agent. The stress inactivation of the biocatalysts decreased the enzyme activity versus three different substrates (pNPB, S-methyl mandelate and triacetin) in a relatively similar fashion. The tryptophane (Trp) fluorescence spectra were different for the biocatalysts, suggesting different enzyme conformations. However, the fluorescence spectra changes during the inactivation were not too different except for the biocatalyst blocked with Asp, suggesting that, except for this biocatalyst, the inactivation pathways may not be so different.


Assuntos
Enzimas Imobilizadas , Lipase , Lipase/metabolismo , Sefarose/química , Enzimas Imobilizadas/química , Butiratos , Etilenodiaminas
9.
Nutrients ; 14(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36364926

RESUMO

Ascophyllum nodosum and Fucus vesiculosus both contain unique polyphenols called phlorotannins. Phlorotannins reportedly possess various pharmacological activities. A previous study reported that the activity of phlorotannin is strongly correlated with the normalization of metabolic function, and phlorotannins are extremely promising nutrients for use in the treatment of metabolic syndrome. To date, no study has explored the antihyperlipidemic effects of phlorotannins from A. nodosum and F. vesiculosus in animal models. Therefore, in the present study, we investigated the effects of phlorotannins using a rat model of high-energy diet (HED)-induced hyperlipidemia. The results showed that the rats that were fed an HED and treated with phlorotannin-rich extract from A. nodosum and F. vesiculosus had significantly lower serum fasting blood sugar (FBS), aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol (TC), triacylglyceride (TG) and free fatty acids (FFAs) levels and hepatic TG level and had higher serum insulin, high-density lipoprotein cholesterol (HDL-C) levels and lipase activity in their fat tissues than in the case with the rats that were fed the HED alone. A histopathological analysis revealed that phlorotannin-rich extract could significantly reduce the size of adipocytes around the epididymis. In addition, the rats treated with phlorotannin-rich extract had significantly lowered interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) levels and increased superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities than did those in the HED group. These results suggested that the phlorotannin-rich extract stimulated lipid metabolism and may have promoted lipase activity in rats with HED-induced hyperlipidemia. Our results indicated that A. nodosum and F. vesiculosus, marine algae typically used as health foods, have strong antihyperlipidemic effects and may, therefore, be useful for preventing atherosclerosis. These algae may be incorporated into antihyperlipidemia pharmaceuticals and functional foods.


Assuntos
Ascophyllum , Fucus , Hiperlipidemias , Doenças Metabólicas , Masculino , Ratos , Animais , Ascophyllum/metabolismo , Metabolismo dos Lipídeos , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/etiologia , Doenças Metabólicas/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Inflamação/tratamento farmacológico , Dieta , Lipase/metabolismo , Hipolipemiantes/uso terapêutico , Colesterol/metabolismo
10.
World J Microbiol Biotechnol ; 38(12): 235, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36229747

RESUMO

As physiological impairments that require replacement therapy continue to increase, so also does the need for improved production of acidic lipase from new microbial sources. Enterobacter cloacae strain UCCM 00116 produced a novel acidic lipase in kernel oil-processing waste-basal broth with 0.023:1 extracellular: intracellular localization ratio. This research re-directed enzyme localization to the extracellular milieu to reduce recovery cost using multi-objective response surface optimization of medium parameters. Results revealed a 1:0.32 extracellular:intracellular lipase ratio. Product formation kinetics, modeled by the Luedeking-Piret function, showed a significant switch from a completely growth-associated intracellular production to a predominantly non-growth-associated extracellular localization through medium optimization. Aqueous two-phase system purification conditions extracted 95.22% lipase with 72.36 purity, a Vmax of 370.37 µmolmin-1, and a Km of 0.63 mmol. Enzyme activity was enhanced by K+ and Ca2+ ions, stable in many organic solvents, except acetone, and had pH and temperature optima at 2.5-3.5 and 50 °C, respectively.


Assuntos
Enterobacter cloacae , Lipase , Acetona , Enterobacter cloacae/metabolismo , Estabilidade Enzimática , Espaço Extracelular , Concentração de Íons de Hidrogênio , Íons , Cinética , Lipase/metabolismo , Solventes/farmacologia , Temperatura
11.
Int J Mol Sci ; 23(19)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36233017

RESUMO

Recent studies have confirmed that chlorophyllase (CLH), a long-found chlorophyll (Chl) dephytylation enzyme for initiating Chl catabolism, has no function in leaf senescence-related Chl breakdown. Yet, CLH is considered to be involved in fruit degreening and responds to external and hormonal stimuli. The purpose of this work was to elucidate in detail the biochemical, structural properties, and gene expression of four CLHs from the Solanum lycopersicum genome so as to understand the roles of Solanum lycopersicum chlorophyllases (SlCLHs). SlCLH1/4 were the predominantly expressed CLH genes during leaf and fruit development/ripening stages, and SlCLH1 in mature green fruit was modulated by light. SlCLH1/2/3/4 contained a highly conserved GHSXG lipase motif and a Ser-Asp-His catalytic triad. We identified Ser159, Asp226, and His258 as the essential catalytic triad by site-directed mutagenesis in recombinant SlCLH1. Kinetic analysis of the recombinant enzymes revealed that SlCLH1 had high hydrolysis activities against Chl a, Chl b, and pheophytin a (Phein a), but preferred Chl a and Chl b over Phein a; SlCLH2/3 only showed very low activity to Chl a and Chl b, while SlCLH4 showed no Chl dephytylation activity. The recombinant SlCLH1/2/3 had different pH stability and temperature optimum. Removal of the predicted N-terminal processing peptide caused a partial loss of activity in recombinant SlCLH1/2 but did not compromise SlCLH3 activity. These different characteristics among SlCLHs imply that they may have different physiological functions in tomato.


Assuntos
Lycopersicon esculentum , Hidrolases de Éster Carboxílico , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Cinética , Lipase/metabolismo , Lycopersicon esculentum/metabolismo
12.
Int J Mol Sci ; 23(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36292971

RESUMO

GDSL-type esterase/lipase (GELP) enzymes have key functions in plants, such as developmental processes, anther and pollen development, and responses to biotic and abiotic stresses. Genes that encode GELP belong to a complex and large gene family, ranging from tens to more than hundreds of members per plant species. To facilitate functional transfer between them, we conducted a genome-wide classification of GELP in 46 plant species. First, we applied an iterative phylogenetic method using a selected set of representative angiosperm genomes (three monocots and five dicots) and identified 10 main clusters, subdivided into 44 orthogroups (OGs). An expert curation for gene structures, orthogroup composition, and functional annotation was made based on a literature review. Then, using the HMM profiles as seeds, we expanded the classification to 46 plant species. Our results revealed the variable evolutionary dynamics between OGs in which some expanded, mostly through tandem duplications, while others were maintained as single copies. Among these, dicot-specific clusters and specific amplifications in monocots and wheat were characterized. This approach, by combining manual curation and automatic identification, was effective in characterizing a large gene family, allowing the establishment of a classification framework for gene function transfer and a better understanding of the evolutionary history of GELP.


Assuntos
Esterases , Magnoliopsida , Esterases/genética , Filogenia , Lipase/metabolismo , Magnoliopsida/genética , Magnoliopsida/metabolismo , Genoma , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Proteínas de Plantas/genética
13.
J Oleo Sci ; 71(11): 1679-1688, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36310055

RESUMO

Stearidonic acid (SDA) is a plant-based n-3 polyunsaturated fatty acid with multiple biological activities. The enrichment of SDA and synthesis of triacylglycerol (TAG) were carried out consecutively via two lipase-catalyzed reactions, hydrolysis, and esterification. First, SDA was enriched into a glyceride fraction from ahiflower seed oil by Candida rugosa lipase-catalyzed hydrolysis. Under the optimum conditions of 35°C, 0.1% lipase powder of Lipase OF, and 50% buffer solution (based on the weight of total substrate), SDA was enriched from 21.6 to 40.7 wt% in glyceride fraction. SDA-enriched TAG was then synthesized from the SDA-enriched glyceride and the SDA-enriched fatty acid via esterification using an in-house immobilized lipase as a biocatalyst. The SDA-enriched fatty acid was obtained from part of the SDA-enriched glyceride by saponification and the in-house immobilized lipase was prepared from Eversa® Transform 2.0 using Lewatit VP OC 1600 as a carrier. The optimum reaction conditions for the synthesis of TAG were a temperature of 50°C, an enzyme loading of 10%, and a vacuum of 10 mmHg. A maximum conversion to TAG of ca. 94% was achieved after 12 h under the optimum conditions.


Assuntos
Enzimas Imobilizadas , Ácidos Graxos Ômega-3 , Triglicerídeos , Esterificação , Lipase/metabolismo , Ácidos Graxos , Óleos Vegetais
14.
Nat Metab ; 4(10): 1352-1368, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36253617

RESUMO

Cysteine dioxygenase 1 (Cdo1) is a key enzyme in taurine synthesis. Here we show that Cdo1 promotes lipolysis in adipose tissue. Adipose-specific knockout of Cdo1 in mice impairs energy expenditure, cold tolerance and lipolysis, exacerbates diet-induced obesity (DIO) and decreases adipose expression of the key lipolytic genes encoding ATGL and HSL, with little effect on adipose taurine levels. White-adipose-specific overexpression of ATGL and HSL blunts the role of adipose Cdo1 deficiency in promoting DIO. Mechanistically, Cdo1 interacts with PPARγ and facilitates the recruitment of Med24, the core subunit of mediator complex, to ATGL and HSL gene promoters, thereby transactivating their expression. Further, mice with transgenic overexpression of Cdo1 show better cold tolerance, ameliorated DIO and higher lipolysis capacity. Thus, we uncover an unexpected and important role of Cdo1 in regulating adipose lipolysis.


Assuntos
Lipólise , PPAR gama , Masculino , Camundongos , Animais , Lipólise/fisiologia , PPAR gama/genética , PPAR gama/metabolismo , Cisteína Dioxigenase/metabolismo , Esterol Esterase/metabolismo , Lipase/metabolismo , Tecido Adiposo/metabolismo , Obesidade/genética , Obesidade/metabolismo , Complexo Mediador/metabolismo , Taurina/metabolismo
15.
Biosci Biotechnol Biochem ; 86(12): 1641-1647, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36288245

RESUMO

2,5-furanediformate Isooctyl is a potential new green biobased plasticizer. At present, most of the preparation methods are chemical methods, which not only have many by-products and are difficult to separate, but also cause environmental pollution. In this paper, the immobilized lipase Novozym435 was used as the catalyst to catalyze the transesterification of 2,5-furanediformate dimethyl ester and isooctyl alcohol to prepare 2,5-furanediformate isoocty in organic medium, and the reaction process was optimized. The optimal process conditions were determined by single factor experiment: in 10 mL toluene system, the additional amount of immobilized lipase Novozym435 was 0.02 g, the molar ratio of 2,5-furanediformate dimethyl ester (1 mmol) and isooctyl alcohol was 1:4, and 1 g 4Å molecular sieve was added to the reaction system, the reaction temperature was 50°C, the reaction time was 24 h, and the conversion rate of 2,5-furanediformate isoocty was 89.63%.


Assuntos
Lipase , Plastificantes , Lipase/metabolismo , Ésteres , Esterificação , Biocatálise , Enzimas Imobilizadas/química , Temperatura
16.
Basic Res Cardiol ; 117(1): 48, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36205817

RESUMO

Although p38 MAP Kinase α (p38 MAPKα) is generally accepted to play a central role in the cardiac stress response, to date its function in maladaptive cardiac hypertrophy is still not unambiguously defined. To induce a pathological type of cardiac hypertrophy we infused angiotensin II (AngII) for 2 days via osmotic mini pumps in control and tamoxifen-inducible, cardiomyocyte (CM)-specific p38 MAPKα KO mice (iCMp38αKO) and assessed cardiac function by echocardiography, complemented by transcriptomic, histological, and immune cell analysis. AngII treatment after inactivation of p38 MAPKα in CM results in left ventricular (LV) dilatation within 48 h (EDV: BL: 83.8 ± 22.5 µl, 48 h AngII: 109.7 ± 14.6 µl) and an ectopic lipid deposition in cardiomyocytes, reflecting a metabolic dysfunction in pressure overload (PO). This was accompanied by a concerted downregulation of transcripts for oxidative phosphorylation, TCA cycle, and fatty acid metabolism. Cardiac inflammation involving neutrophils, macrophages, B- and T-cells was significantly enhanced. Inhibition of adipose tissue lipolysis by the small molecule inhibitor of adipocytetriglyceride lipase (ATGL) Atglistatin reduced cardiac lipid accumulation by 70% and neutrophil infiltration by 30% and went along with an improved cardiac function. Direct targeting of neutrophils by means of anti Ly6G-antibody administration in vivo led to a reduced LV dilation in iCMp38αKO mice and an improved systolic function (EF: 39.27 ± 14%). Thus, adipose tissue lipolysis and CM lipid accumulation augmented cardiac inflammation in iCMp38αKO mice. Neutrophils, in particular, triggered the rapid left ventricular dilatation. We provide the first evidence that p38 MAPKα acts as an essential switch in cardiac adaptation to PO by mitigating metabolic dysfunction and inflammation. Moreover, we identified a heart-adipose tissue-immune cell crosstalk, which might serve as new therapeutic target in cardiac pathologies.


Assuntos
Insuficiência Cardíaca , Miócitos Cardíacos , Tecido Adiposo/metabolismo , Angiotensina II/metabolismo , Animais , Cardiomegalia/metabolismo , Ácidos Graxos/metabolismo , Inflamação/metabolismo , Lipase/metabolismo , Lipase/uso terapêutico , Lipídeos/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Neutrófilos/metabolismo , Tamoxifeno/metabolismo , Tamoxifeno/uso terapêutico , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/uso terapêutico
17.
Int J Biol Sci ; 18(15): 5740-5752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36263170

RESUMO

The small intestine is main site of exogenous lipid digestion and absorption, and it is important for lipid metabolic homeostasis. Cell death-inducing DNA fragmentation-factor like effector C (CIDEC) is active in lipid metabolism in tissues other than those in the intestine. We developed small intestine-specific CIDEC (SI-CIDEC-/-) knockout C57BL/6J mice by Cre/LoxP recombination to investigate the in vivo effects of intestinal CIDEC on lipid metabolism. Eight-week-old SI-CIDEC-/- mice fed a high-fat diet for 14 weeks had 15% lower body weight, 30% less body fat mass, and 79% lower liver triglycerides (TG) than wild-type (WT) mice. In addition, hepatic steatosis and fatty liver inflammation were less severe in knockout mice fed a high-fat diet (HFD) compared with wild-type mice fed an HFD. SI-CIDEC-/- mice fed an HFD diet had lower serum TG and higher fecal TG and intestinal lipase activity than wild-type mice. Mechanistic studies showed that CIDEC accelerated phosphatidic acid synthesis by interacting with 1-acylglycerol-3-phosphate-O-acyltransferase to promote TG accumulation. This study identified a new interacting protein and previously unreported CIDEC mechanisms that revealed its activity in lipid metabolism of the small intestine.


Assuntos
Fígado Gorduroso , Metabolismo dos Lipídeos , Obesidade , Proteínas , Animais , Camundongos , Aciltransferases/metabolismo , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Glicerídeos/metabolismo , Intestino Delgado/metabolismo , Lipase/metabolismo , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Obesidade/metabolismo , Fosfatos/metabolismo , Ácidos Fosfatídicos , Triglicerídeos/metabolismo , Proteínas/metabolismo
18.
Metabolism ; 137: 155331, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36228741

RESUMO

BACKGROUND: The triglyceride (TG) transfer activity of microsomal triglyceride transfer protein (MTP) is essential for lipoprotein assembly in the liver and intestine; however, its function in adipose tissue, which does not assemble lipoproteins, is unknown. Here we have elucidated the function of MTP in adipocytes. APPROACH AND RESULTS: We demonstrated that MTP is present on lipid droplets in human adipocytes. Adipose-specific MTP deficient (A-Mttp-/-) male and female mice fed an obesogenic diet gained less weight than Mttpf/f mice, had less fat mass, smaller adipocytes and were insulin sensitive. A-Mttp-/- mice showed higher energy expenditure than Mttpf/f mice. During a cold challenge, A-Mttp-/- mice maintained higher body temperature by mobilizing more fatty acids. Biochemical studies indicated that MTP deficiency de-repressed adipose triglyceride lipase (ATGL) activity and increased TG lipolysis. Both wild type MTP and mutant MTP deficient in TG transfer activity interacted with and inhibited ATGL activity. Thus, the TG transfer activity of MTP is not required for ATGL inhibition. C-terminally truncated ATGL that retains its lipase activity interacted less efficiently than full-length ATGL. CONCLUSION: Our findings demonstrate that adipose-specific MTP deficiency increases ATGL-mediated TG lipolysis and enhances energy expenditure, thereby resisting diet-induced obesity. We speculate that the regulatory function of MTP involving protein-protein interactions might have evolved before the acquisition of TG transfer activity in vertebrates. Adipose-specific inhibition of MTP-ATGL interactions may ameliorate obesity while avoiding the adverse effects associated with inhibition of the lipid transfer activity of MTP.


Assuntos
Lipase , Lipólise , Masculino , Feminino , Camundongos , Humanos , Animais , Lipase/metabolismo , Adipócitos/metabolismo , Obesidade/metabolismo , Lipídeos/farmacologia
19.
Cells ; 11(19)2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36230994

RESUMO

Disturbances in cardiac lipid metabolism are associated with the development of cardiac hypertrophy and heart failure. Spontaneously hypertensive rats (SHRs), a genetic model of primary hypertension and pathological left ventricular (LV) hypertrophy, have high levels of diacylglycerols in cardiomyocytes early in development. However, the exact effect of lipids and pathways that are involved in their metabolism on the development of cardiac dysfunction in SHRs is unknown. Therefore, we used SHRs and Wistar Kyoto (WKY) rats at 6 and 18 weeks of age to analyze the impact of perturbations of processes that are involved in lipid synthesis and degradation in the development of LV hypertrophy in SHRs with age. Triglyceride levels were higher, whereas free fatty acid (FA) content was lower in the LV in SHRs compared with WKY rats. The expression of de novo FA synthesis proteins was lower in cardiomyocytes in SHRs compared with corresponding WKY controls. The higher expression of genes that are involved in TG synthesis in 6-week-old SHRs may explain the higher TG content in these rats. Adenosine monophosphate-activated protein kinase phosphorylation and peroxisome proliferator-activated receptor α protein content were lower in cardiomyocytes in 18-week-old SHRs, suggesting a lower rate of ß-oxidation. The decreased protein content of α/ß-hydrolase domain-containing 5, adipose triglyceride lipase (ATGL) activator, and increased content of G0/G1 switch protein 2, ATGL inhibitor, indicating a lower rate of lipolysis in the heart in SHRs. In conclusion, the present study showed that the development of LV hypertrophy and myocardial dysfunction in SHRs is associated with triglyceride accumulation, attributable to a lower rate of lipolysis and ß-oxidation in cardiomyocytes.


Assuntos
Hipertrofia Ventricular Esquerda , Metabolismo dos Lipídeos , Monofosfato de Adenosina/farmacologia , Animais , Diglicerídeos/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/patologia , Lipase/metabolismo , Miócitos Cardíacos/metabolismo , PPAR alfa/metabolismo , Proteínas Quinases/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Triglicerídeos/metabolismo
20.
J Physiol Pharmacol ; 73(3)2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36302529

RESUMO

Endothelial lipase is synthetized almost exclusively in endothelial cells and then fixed on the luminal surface of the endothelium by means of heparan sulphate proteoglycans. The enzyme is expressed in the endothelium of nearly all tissues and the degree of expression is higher in richly vascularized tissues than in the less vascularized ones. The endothelial lipase expression in tissues is upregulated by shear and cyclic stress, angiotensin II and hypertension. The plasma enzyme level is elevated by pro-inflammatory cytokines, in metabolic syndrome and obesity. Prolonged exercise reduces the plasma enzyme level in the rat. The activity of the enzyme is inhibited by: sphingomyelin, angiopoietin-like protein 3 and 4, and insulin. Endothelial lipase reduces the plasma high density lipoprotein concentration and changes its properties. The enzyme is considered to be the main regulator of the plasma high density lipoprotein concentration. The plasma endothelial lipase concentration is elevated in coronary atherosclerosis and it is inversely correlated with the plasma high density lipoprotein level. The enzyme is considered to exert mostly pro-atherogenic effects. Its action as triglyceride lipase is important in hypertriglyceridemia.


Assuntos
Aterosclerose , Lipase Lipoproteica , Animais , Ratos , Células Endoteliais/metabolismo , Lipase/metabolismo , Lipase Lipoproteica/metabolismo , Lipoproteínas HDL , Humanos
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