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1.
Nat Commun ; 13(1): 2542, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538051

RESUMO

Statins are a class of drug widely prescribed for the prevention of cardiovascular disease, with pleiotropic cellular effects. Statins inhibit HMG-CoA reductase (HMGCR), which converts the metabolite HMG-CoA into mevalonate. Recent discoveries have shown HMG-CoA is a reactive metabolite that can non-enzymatically modify proteins and impact their activity. Therefore, we predicted that inhibition of HMGCR by statins might increase HMG-CoA levels and protein modifications. Upon statin treatment, we observe a strong increase in HMG-CoA levels and modification of only a single protein. Mass spectrometry identifies this protein as fatty acid synthase (FAS), which is modified on active site residues and, importantly, on non-lysine side-chains. The dynamic modifications occur only on a sub-pool of FAS that is located near HMGCR and alters cellular signaling around the ER and Golgi. These results uncover communication between cholesterol and lipid biosynthesis by the substrate of one pathway inhibiting another in a rapid and reversible manner.


Assuntos
Doenças Cardiovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Doenças Cardiovasculares/prevenção & controle , Colesterol/metabolismo , Ácido Graxo Sintases , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Ácido Mevalônico/metabolismo
2.
Cell Rep ; 39(5): 110776, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35508140

RESUMO

Assemblies of tau can transit between neurons, seeding aggregation in a prion-like manner. To accomplish this, tau must cross cell-limiting membranes, a process that is poorly understood. Here, we establish assays for the study of tau entry into the cytosol as a phenomenon distinct from uptake, in real time, and at physiological concentrations. The entry pathway of tau is cell type specific and, in neurons, highly sensitive to cholesterol. Depletion of the cholesterol transporter Niemann-Pick type C1 or extraction of membrane cholesterol renders neurons highly permissive to tau entry and potentiates seeding even at low levels of exogenous tau assemblies. Conversely, cholesterol supplementation reduces entry and almost completely blocks seeded aggregation. Our findings establish entry as a rate-limiting step to seeded aggregation and demonstrate that dysregulated cholesterol, a feature of several neurodegenerative diseases, potentiates tau aggregation by promoting entry of tau assemblies into the cell interior.


Assuntos
Doença de Alzheimer , Príons , Doença de Alzheimer/metabolismo , Colesterol/metabolismo , Citosol/metabolismo , Humanos , Neurônios/metabolismo , Príons/metabolismo , Proteínas tau/metabolismo
3.
Sheng Li Xue Bao ; 74(2): 209-216, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35503068

RESUMO

Mounting evidence has shown that exercise exerts extensive beneficial effects, including preventing and protecting against chronic diseases, through improving metabolism and other mechanisms. Recent studies have shown that exercise preconditioning affords significant cardioprotective effects. However, whether exercise preconditioning improves high fat diet (HFD)-induced obesity and lipid metabolic disorder remains unknown. The study was aimed to explore the effects of exercise preconditioning on HFD-induced obesity and lipid metabolic disorder in mice. 4-week-old C57BL/6 mice were subjected to swimming or sedentary control for 3 months, and then were fed with normal diet (ND) or HFD for 4 more months. The results showed that the blood glucose was decreased, and the glucose tolerance and grip strength were increased in exercised mice after training. Exercise preconditioning failed to improve HFD-induced body weight gain, but improved HFD-induced glucose intolerance. Exercise preconditioning showed no significant effects on both exercise capacity and physical activity in ND- and HFD-fed mice. HFD feeding increased total cholesterol and low density lipoprotein (LDL) levels in circulation, promoted subcutaneous fat and epididymal fat accumulation in mice. Exercise preconditioning increased circulating high density lipoprotein (HDL) and decreased circulating LDL, without affecting the subcutaneous fat and epididymal fat in HFD-fed mice. HFD feeding increased liver weight and hepatic total cholesterol contents, and dysregulated the expressions of several mitochondria function-related proteins in mice. These abnormalities were partially reversed by exercise preconditioning. Together, these results suggest that exercise preconditioning can partially reverse the HFD-induced lipid metabolic disorder and hepatic dysfunction, and these beneficial effects of exercise sustain for a period of time, even after exercise is discontinued.


Assuntos
Dieta Hiperlipídica , Obesidade , Animais , Colesterol/metabolismo , Dieta Hiperlipídica/efeitos adversos , Lipídeos , Fígado , Camundongos , Camundongos Endogâmicos C57BL
4.
Adv Exp Med Biol ; 1372: 119-143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35503178

RESUMO

High plasma levels of lipids and/or lipoproteins are risk factors for atherosclerosis, nonalcoholic fatty liver disease (NAFLD), obesity, and diabetes. These four conditions have also been identified as risk factors leading to the development of chronic kidney disease (CKD). Although many pathways that generate high plasma levels of these factors have been identified, most clinical and physiologic dysfunction results from aberrant assembly and secretion of lipoproteins. The results of several published studies suggest that elevated levels of low-density lipoprotein (LDL)-cholesterol are a risk factor for atherosclerosis, myocardial infarction, coronary artery calcification associated with type 2 diabetes, and NAFLD. Cholesterol metabolism has also been identified as an important pathway contributing to the development of CKD; clinical treatments designed to alter various steps of the cholesterol synthesis and metabolism pathway are currently under study. Cholesterol synthesis and catabolism contribute to a multistep process with pathways that are regulated at the cellular level in renal tissue. Cholesterol metabolism may also be regulated by the balance between the influx and efflux of cholesterol molecules that are capable of crossing the membrane of renal proximal tubular epithelial cells and podocytes. Cellular accumulation of cholesterol can result in lipotoxicity and ultimately kidney dysfunction and failure. Thus, further research focused on cholesterol metabolism pathways will be necessary to improve our understanding of the impact of cholesterol restriction, which is currently a primary intervention recommended for patients with dyslipidemia.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Insuficiência Renal Crônica , Colesterol/metabolismo , Feminino , Humanos , Lipoproteínas/metabolismo , Masculino , Insuficiência Renal Crônica/terapia
5.
Front Immunol ; 13: 791267, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529872

RESUMO

Host cholesterol metabolism remodeling is significantly associated with the spread of human pathogenic coronaviruses, suggesting virus-host relationships could be affected by cholesterol-modifying drugs. Cholesterol has an important role in coronavirus entry, membrane fusion, and pathological syncytia formation, therefore cholesterol metabolic mechanisms may be promising drug targets for coronavirus infections. Moreover, cholesterol and its metabolizing enzymes or corresponding natural products exert antiviral effects which are closely associated with individual viral steps during coronavirus replication. Furthermore, the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 infections are associated with clinically significant low cholesterol levels, suggesting cholesterol could function as a potential marker for monitoring viral infection status. Therefore, weaponizing cholesterol dysregulation against viral infection could be an effective antiviral strategy. In this review, we comprehensively review the literature to clarify how coronaviruses exploit host cholesterol metabolism to accommodate viral replication requirements and interfere with host immune responses. We also focus on targeting cholesterol homeostasis to interfere with critical steps during coronavirus infection.


Assuntos
COVID-19 , Antivirais/uso terapêutico , Colesterol/metabolismo , Humanos , Replicação Viral
6.
J Obes ; 2022: 1015669, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35528246

RESUMO

Diabetes is a serious public health problem in low- and middle-income countries. There is a strong link between hyperglycemia, oxidative stress, inflammation, and the development of diabetes mellitus. PI3K/Akt/mTOR is the main signaling pathway of insulin for controlling lipid and glucose metabolism. P-cymene is an aromatic monoterpene with a widespread range of therapeutic properties including antioxidant and anti-inflammatory activity. In the present study, the antidiabetic effects of p-cymene were investigated. Diabetes was induced using streptozotocin in male Wistar rats. The effects of p-cymene and metformin were studied on levels of glucose (Glu), lipid profile, liver enzymes, oxidative stress, and the expression of Akt, phospho-Akt, and mTOR (mammalian target of rapamycin) proteins, using biochemical, histological, and immunohistochemical analysis. Data have shown that p-cymene can improve serum levels of Glu, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein (LDL), very-low-density lipoprotein (VLDL), alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), and the expression of mTOR, Akt, and phospho-Akt protein in diabetic animals. These results suggest that p-cymene has hypoglycemia, hypolipidemia, and antioxidant properties. It can regulate Akt/mTOR pathway and reduce hepatic and pancreas injury. It can be suggested for diabetes management alone or simultaneously with metformin.


Assuntos
Cimenos , Diabetes Mellitus Experimental , Metformina , Animais , Antioxidantes/metabolismo , Glicemia/metabolismo , Colesterol/metabolismo , Cimenos/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Hipoglicemiantes/farmacologia , Fígado/metabolismo , Masculino , Metformina/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Estreptozocina , Serina-Treonina Quinases TOR/metabolismo , Triglicerídeos
7.
Biomed Res Int ; 2022: 6584645, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35601145

RESUMO

Introduction: Atherosclerosis (AS) is a chronic inflammatory disease characterized by lipid metabolism disorder and vascular endothelial damage. Albiflorin (AF) has been certified to be effective in the therapy of certain inflammatory diseases, while the therapeutic effect and mechanism of AF on AS have not been fully elucidated. Material and Methods. Model cells for AS were created by inducing oxidized low-density lipoprotein (Ox-LDL) in human umbilical vein endothelial cells (HUVECs). After processing with AF and interleukin-1 receptor-associated kinase 1- (IRAK1-) overexpressed plasmid, cell viability was assessed by CCK-8; cholesterol efflux was tested using liquid scintillation counter; IL-6 and TNF-α levels were determined with ELISA kits; ROS and apoptosis were confirmed using Flow cytometry. Besides, IRAK1-TAK1 pathway and apoptosis- and mitochondrial fusion-related proteins were monitored with western blotting analysis. Results: Our results verified that AF could not only dramatically accelerate viability and cholesterol efflux but also attenuate inflammation, ROS production, and apoptosis in Ox-LDL-induced HUVECs. Meanwhile, AF could prominently prevent the activation of IRAK1-TAK1 pathway, downregulate apoptosis-related proteins, and upregulate mitochondrial fusion-related proteins in Ox-LDL-induced HUVECs. Moreover, we testified that IRAK1 overexpression memorably could reverse suppression of AF on inflammation, apoptosis, and IRAK1-TAK1 pathway and enhancement of AF on viability, cholesterol efflux, and mitochondrial fusion in Ox-LDL-induced HUVECs. Conclusions: By blocking the IRAK1/TAK1 pathway, AF can significantly slow the course of AS, suggesting that it could be a viable therapeutic option for AS.


Assuntos
Aterosclerose , Quinases Associadas a Receptores de Interleucina-1 , Apoptose , Aterosclerose/metabolismo , Hidrocarbonetos Aromáticos com Pontes , Colesterol/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Lipoproteínas LDL/metabolismo , Espécies Reativas de Oxigênio/metabolismo
8.
Food Funct ; 13(10): 5820-5837, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35543349

RESUMO

Alcoholic liver injury is mainly caused by long-term excessive alcohol consumption and has become a global public threat to human health. It is well known that Ganoderma lucidum has excellent beneficial effects on liver function and lipid metabolism. The object of this study was to investigate the hepatoprotective effects of ganoderic acid A (GAA, one of the main triterpenoids in G. lucidum) against alcohol-induced liver injury and reveal the underlying mechanisms of its protective effects. The results showed that oral administration of GAA significantly inhibited the abnormal elevation of the liver index, serum total triglyceride (TG), cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in mice exposed to alcohol intake, and also significantly protected the liver against alcohol-induced excessive lipid accumulation and pathological changes. Besides, alcohol-induced oxidative stress in the liver was significantly ameliorated by the dietary intervention of GAA through decreasing the hepatic levels of lactate dehydrogenase (LDH) and malondialdehyde (MDA), and increasing hepatic activities of catalase (CAT), superoxide dismutase (SOD), alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), and hepatic levels of glutathione (GSH). In addition, GAA intervention evidently ameliorated intestinal microbial disorder by markedly increasing the abundance of Muribaculaceae, Prevotellaceae, Jeotgalicoccus, Bilophila, Family_XIII_UCG_001, Aerococcus, Ruminococcaceae_UCG_005, Harryflintia, Christensenellaceae, Rumonpcpccaceae, Prevotelaceae_UCG_001, Clostridiales_vadinBB60_group, Parasutterella and Bifidobacterium, but decreasing the proportion of Lactobacillus, Burkholderia_Caballeroria_Paraburkholderia, Escherichia_Shigella and Erysipelatoclostridium. Furthermore, liver metabolomics based on UPLC-QTOF/MS demonstrated that oral administration of GAA had a significant regulatory effect on the composition of liver metabolites in mice exposed to alcohol intake, especially the levels of the biomarkers involved in the metabolic pathways of riboflavin metabolism, glycine, serine and threonine metabolism, pyruvate metabolism, glycolysis/gluconeogenesis, biosynthesis of unsaturated fatty acids, synthesis and degradation of ketone bodies, fructose and mannose metabolism. Moreover, dietary supplementation of GAA significantly regulated the hepatic mRNA levels of lipid metabolism and inflammatory response related genes. Conclusively, these findings demonstrate that GAA has beneficial effects on alleviating alcohol-induced liver injury and is expected to become a new functional food ingredient for the prevention of alcoholic liver injury.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Reishi , Animais , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Colesterol/metabolismo , Etanol/farmacologia , Ácidos Heptanoicos , Lanosterol/análogos & derivados , Lanosterol/farmacologia , Metabolismo dos Lipídeos , Fígado/metabolismo , Camundongos , Estresse Oxidativo
9.
Adv Exp Med Biol ; 1377: 153-161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35575928

RESUMO

In previous chapters, we know that high-density lipoproteins (HDLs) could act at multiple cell lines and then trigger intracellular molecular pathway to prevent several metabolic diseases. Besides the classic genes regulating cholesterol efflux and reverse cholesterol transport (RCT), microRNAs (miRNAs) could also affect HDLs biogenesis, metabolism, and functions. This chapter summarizes the miRNAs, which regulate HDLs functions in table. In addition, HDLs are good vectors for miRNAs. They could carry miRNAs in circulation and take them into several cells such as macrophages and endothelial cells. Complete understanding of the miRNAs associated with HDL regulation would give us broader insights to prevent and treat metabolic diseases.


Assuntos
MicroRNAs , Transporte Biológico/genética , Colesterol/metabolismo , HDL-Colesterol/metabolismo , Lipoproteínas HDL/genética , Lipoproteínas HDL/metabolismo , Macrófagos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
10.
Adv Exp Med Biol ; 1377: 95-107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35575923

RESUMO

Cholesterol is a major component of mammalian cell membranes and plays important structural and functional roles. However, excessive cholesterol accumulation is toxic to cells and constitutes the molecular basis for many diseases, especially atherosclerotic cardiovascular disease. Thus, cellular cholesterol is tightly regulated to maintain a homeostasis. Reverse cholesterol transport (RCT) is thought to be one primary pathway to eliminate excessive cholesterol from the body. The first and rate-limiting step of RCT is ATP-binding cassette (ABC) transports A1 (ABCA1)- and ABCG1-dependent cholesterol efflux. In the process, ABCA1 mediates initial transport of cellular cholesterol to apolipoprotein A-I (apoA-I) for forming nascent high-density lipoprotein (HDL) particles, and ABCG1 facilitates subsequent continued cholesterol efflux to HDL for further maturation. In this chapter, we summarize the roles of ABCA1 and ABCG1 in maintaining cellular cholesterol homoeostasis and discuss the underlying mechanisms by which they mediate cholesterol export.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Aterosclerose/metabolismo , Colesterol/metabolismo , Mamíferos/metabolismo , Animais , Aterosclerose/genética , Aterosclerose/prevenção & controle , Transporte Biológico , Homeostase , Humanos
11.
ACS Chem Neurosci ; 13(9): 1456-1466, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35467841

RESUMO

Cellular hypoxia causes numerous pathophysiological conditions associated with the disruption of oxygen homeostasis. Under oxygen-deficient conditions, cells adapt by controlling the cellular functions to facilitate the judicious use of available oxygen, such as cessation of cell growth and proliferation. In higher eukaryotes, the process of cholesterol biosynthesis is intimately coupled to the availability of oxygen, where the synthesis of one molecule of cholesterol requires 11 molecules of O2. Cholesterol is an essential component of higher eukaryotic membranes and is crucial for the physiological functions of several membrane proteins and receptors. The serotonin1A receptor, an important neurotransmitter G protein-coupled receptor associated with cognition and memory, has previously been shown to depend on cholesterol for its signaling and function. In this work, in order to explore the interdependence of oxygen levels, cholesterol biosynthesis, and the function of the serotonin1A receptor, we developed a cellular hypoxia model to explore the function of the human serotonin1A receptor heterologously expressed in Chinese hamster ovary cells. We observed cell cycle arrest at G1/S phase and the accumulation of lanosterol in cell membranes under hypoxic conditions, thereby validating our cellular model. Interestingly, we observed a significant reduction in ligand binding and disruption of downstream cAMP signaling of the serotonin1A receptor under hypoxic conditions. To the best of our knowledge, our results represent the first report linking the function of the serotonin1A receptor with hypoxia. From a broader perspective, these results contribute to our overall understanding of the molecular basis underlying neurological conditions often associated with hypoxia-induced brain dysfunction.


Assuntos
Receptor 5-HT1A de Serotonina/metabolismo , Serotonina , Animais , Células CHO , Hipóxia Celular , Colesterol/metabolismo , Cricetinae , Cricetulus , Humanos , Hipóxia , Oxigênio , Serotonina/metabolismo
12.
Bioengineered ; 13(3): 6440-6449, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35486473

RESUMO

Our study aimed to explore the effect of C-type lectin-like receptor 2 (CLEC2) expression level on oxidized low-density lipoprotein (ox-LDL)-induced macrophage damage and the regulatory mechanism of macrophage foaming. Foam cells were derived from RAW264.7 by ox-LDL, and the cell viability was detected by cell counting kit-8 (CCK-8) assay. Enzyme-linked immunosorbent assay (ELISA) was applied to detect the levels of inflammatory cytokines tumor necrosis factor (TNF-α), Interleukin-6 (IL-6), and Interleulin-1ß (IL-1ß). Small interfering CLEC2 (si-CLEC2) was synthesized and transfected into RAW264.7, and the apoptosis rate was analyzed by flow cytometry. Western blotting was employed to detect the protein expressions of Janus kinase 1 (JAK1), Signal transducers and activators of transcription-1 (STAT1), phosphorylation-JAK1 (p-JAK1), phosphorylation-STAT1 (p-STAT1), CLEC2, and the apoptosis-related proteins. The levels of total cholesterol (TC) and free cholesterol (FC) were measured using colorimetric kits. Results showed that ox-LDL could activate the JAK1/STAT1 pathway of macrophages and up-regulate the expression of CLEC2. CLEC2 knockdown could reduce macrophage inflammation and lipid accumulation. Inactivating JAK1/STAT1 pathway with JAK1 inhibitor can significantly reduce the phosphorylation of STAT1 and alleviate the ox-LDL-induced damage in macrophages by regulating the expression of CLEC2. In conclusion, targeting JAK1/STAT1 to inhibit CLEC2 can attenuate ox-LDL-induced macrophage damage. This study enriched the pathogenesis of atherosclerosis and provided the possible treatment targets.


Assuntos
Aterosclerose , Lectinas Tipo C , Macrófagos , Animais , Aterosclerose/metabolismo , Linhagem Celular , Colesterol/metabolismo , Janus Quinase 1/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Camundongos , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
Biochim Biophys Acta Biomembr ; 1864(8): 183946, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35483421

RESUMO

The Smoothened receptor (SMO, a 7 pass transmembrane domain, Class F GPCR family protein) plays a crucial role in the Hedgehog (HH) signaling pathway, which is involved in embryonic development and is implicated in various types of cancer throughout the animal kingdom. In the absence of HH signaling, SMO is inhibited by Patched 1 (PTC1; a 12 pass transmembrane domain protein), which is localized in the primary cilia. HH binding leads to the dislocation of PTC1 from the cilia, thus making way for SMO to localize in the primary cilia, as an essential prerequisite for its activation. We have carried out MARTINI coarse-grained molecular dynamics simulations of SMO in POPC and in ciliary membrane models, respectively, to study the interactions of SMO with cholesterol and other lipid molecules in the ciliary membrane, and to gain molecular-level insights into the role of the primary cilia in shaping the functional dynamics of SMO. We are able to identify the interaction of membrane cholesterols with definite sites and domains within SMO and relate them with known cholesterol-binding sequence and structure motifs. We show that cholesterol interactions with the transmembrane domain TMD, unlike those with the cysteine-rich domain (CRD) and the intracellular domain (ICD), are through residues belonging to known cholesterol-binding motifs. Notably, a few persistent interactions of cholesterol with lower TM cholesterol-binding domains are governed by the presence of multiple cholesterol-binding motifs. These analyses have also helped to identify and define a strict cholesterol consensus motif (CCM), which may well steer cholesterol into the hitherto identified binding sites within the TMD of SMO. We have also reported the interaction of phosphatidylinositol 4-phosphate with the intracellular region of transmembrane (TM) helices (TM1, TM3, TM4, and TM5), intracellular loop1, helix8, and Arg/Lys clusters of the ICD. Structural analysis of SMO domains shows significant changes in the CRD and ICD, during the course of the simulation. Further detailed analysis of the dynamics of the TMD reveals the movements of TM5, TM6, and TM7, linked with the helix8, which are possibly involved in shaping the conformational disposition of the ICD. The movement of these TM helices could possibly be a consequence of interactions involving the extracellular domain and extracellular loops. In addition, our analysis also shows that phosphatidylinositol-4-phosphate (PI4P), along with some ICD cholesterols, are implicated in anchoring SMO in the membrane.


Assuntos
Cílios , Proteínas Hedgehog , Animais , Colesterol/metabolismo , Cílios/metabolismo , Proteínas Hedgehog/metabolismo , Lipídeos de Membrana/metabolismo , Receptor Smoothened/química , Receptor Smoothened/metabolismo
14.
Artigo em Russo | MEDLINE | ID: mdl-35485655

RESUMO

The high prevalence of the combination of arterial hypertension (AH) with coronary heart disease (CHD) suggests the improvement of their treatment methods. In this regard, it is of interest to assess the dynamics of the clinical picture of patients against the background of pathogenetically determined subcellular and systemic changes under the influence of laser therapy (LT). OBJECTIVE: To evaluate the clinical effect of LT in patients with hypertension in combination with coronary artery disease and trace its relationship with the dynamics of the structure of the lipid bilayer of the erythrocyte membrane and changes in the microvascular bed. MATERIAL AND METHODS: We examined 65 male patients (mean age 50.9±6.3 years) with II-III degree AH in combination with coronary artery disease with angina pectoris. Among them, 40 patients received a 10-day course of LT, and 25 patients underwent simulated laser irradiation. At the initial stage and after 1 month, all patients underwent a bicycle exercise test, a study of the lipid composition of the erythrocyte membrane, including the main fractions of phospholipids and free cholesterol, as well as the level of intracellular Ca2+ and lipid peroxidation products - malondialdehyde and diene conjugates. Microcirculation was assessed using the method of conjunctival biomicroscopy. RESULTS: One month after the course of LT, patients showed a significant increase in exercise tolerance by 37.8%, a decrease in systolic blood pressure with a standard load by 9.9%. The improvement of the clinical picture occurred against the background of a decrease in the activity of lipid peroxidation and structural changes in the cell membrane: an increase in polyunsaturated fractions of phospholipids and a decrease in the cholesterol content, as well as a decrease in the Ca2+ level in the cell from 0.23 [0.19; 0.32] to 0.20 [0.16; 0.26] mmol/l. The results of the analysis of conjunctival biomicroscopy demonstrated a statistically significant decrease in the ratio of arteriolovenular calibers, a limitation of the severity of sludge syndrome by 59%, and an almost twofold (from 3.9±0.52 to 7.2±1.23 cap/mm2) increase in capillary density. CONCLUSION: The data obtained showed that in patients with hypertension in combination with coronary artery disease, LT causes positive changes in the lipid structure of the cell membrane and microcirculation parameters, which is accompanied by a hypotensive effect and an improvement in the clinical and functional state of patients.


Assuntos
Doença da Artéria Coronariana , Hipertensão , Terapia a Laser , Adulto , Colesterol/análise , Colesterol/metabolismo , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/metabolismo , Membrana Eritrocítica/química , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/efeitos da radiação , Feminino , Humanos , Hipertensão/complicações , Hipertensão/radioterapia , Masculino , Microcirculação , Pessoa de Meia-Idade , Fosfolipídeos/análise , Fosfolipídeos/metabolismo
15.
Oxid Med Cell Longev ; 2022: 2017815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464766

RESUMO

Purpose: Activation of NLR (nucleotide-binding and leucine-rich repeat immune receptor) family pyrin domain containing 3 (NLRP3) inflammasome mediating interleukin- (IL-) 1ß secretion has emerged as an important component of inflammatory processes in atherogenesis. The nuclear receptor Nur77 is highly expressed in human atherosclerotic lesions; however, its functional role in macrophage NLRP3 inflammasome activation has not yet been clarified. Methods, Materials, and Results. Eight-week-old apolipoprotein E (ApoE)-/- and ApoE-/- Nur77-/- mice that were fed a Western diet underwent partial ligation of the left common carotid artery (LCCA) and left renal artery (LRA) to induce atherogenesis. Four weeks later, severe plaque burden associated with increased lipid deposition, reduced smooth muscle cells, macrophage infiltration, and decreased collagen expression was identified in ApoE-/- Nur77-/- mice compared with those in ApoE-/- mice. ApoE-/- Nur77-/- mice showed increased macrophage inflammatory responses in carotid atherosclerotic lesions. In vitro studies demonstrated that oxidized low-density lipoprotein cholesterol (ox-LDL) increased the release of lactate dehydrogenase (LDH) and upregulated the expressions of cleaved caspase-1, cleaved IL-1ß and gasdermin D (GSMD) in WT peritoneal macrophages (PMs) in a NLRP3-dependent manner. Nur77-/- PMs exhibited a further increased level of NLRP3 inflammasome-mediated inflammation under ox-LDL treatment compared with WT PMs. Mechanistically, Nur77 could bind to the promoter of NLRP3 and inhibit its transcriptional activity. Conclusions: This study demonstrated that Nur77 deletion promotes atherogenesis by exacerbating NLRP3 inflammasome-mediated inflammation.


Assuntos
Aterosclerose , Inflamassomos , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/patologia , Colesterol/metabolismo , Inflamassomos/metabolismo , Inflamação/patologia , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares
16.
Front Immunol ; 13: 868958, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386720

RESUMO

HIF-1α exerts both detrimental and beneficial actions in atherosclerosis. While there is evidence that HIF-1α could be pro-atherogenic within the atheromatous plaque, experimental models of atherosclerosis suggest a more complex role that depends on the cell type expressing HIF-1α. In atheroma plaques, HIF-1α is stabilized by local hypoxic conditions and by the lipid microenvironment. Macrophage exposure to oxidized LDLs (oxLDLs) or to necrotic plaque debris enriched with oxysterols induces HIF-1α -dependent pathways. Moreover, HIF-1α is involved in many oxLDL-induced effects in macrophages including inflammatory response, angiogenesis and metabolic reprogramming. OxLDLs activate toll-like receptor signaling pathways to promote HIF-1α stabilization. OxLDLs and oxysterols also induce NADPH oxidases and reactive oxygen species production, which subsequently leads to HIF-1α stabilization. Finally, recent investigations revealed that the activation of liver X receptor, an oxysterol nuclear receptor, results in an increase in HIF-1α transcriptional activity. Reciprocally, HIF-1α signaling promotes triglycerides and cholesterol accumulation in macrophages. Hypoxia and HIF-1α increase the uptake of oxLDLs, promote cholesterol and triglyceride synthesis and decrease cholesterol efflux. In conclusion, the impact of HIF-1α on cholesterol homeostasis within macrophages and the feedback activation of the inflammatory response by oxysterols via HIF-1α could play a deleterious role in atherosclerosis. In this context, studies aimed at understanding the specific mechanisms leading to HIF-1α activation within the plaque represents a promising field for research investigations and a path toward development of novel therapies.


Assuntos
Aterosclerose , Oxisteróis , Placa Aterosclerótica , Aterosclerose/metabolismo , Colesterol/metabolismo , Humanos , Hipóxia/metabolismo , Macrófagos/metabolismo , Oxisteróis/metabolismo , Placa Aterosclerótica/metabolismo
17.
Int J Mol Sci ; 23(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35409148

RESUMO

Atherosclerosis, accompanied by inflammation and metabolic disorders, is the primary cause of clinical cardiovascular death. In recent years, unhealthy lifestyles (e.g., sedentary lifestyles) have contributed to a worldwide epidemic of atherosclerosis. Exercise is a known treatment of atherosclerosis, but the precise mechanisms are still unknown. Here, we show that 12 weeks of regular exercise training on a treadmill significantly decreased lipid accumulation and foam cell formation in ApoE-/- mice fed with a Western diet, which plays a critical role in the process of atherosclerosis. This was associated with an increase in ß-hydroxybutyric acid (BHB) levels in the serum. We provide evidence that BHB treatment in vivo or in vitro increases the protein levels of cholesterol transporters, including ABCA1, ABCG1, and SR-BI, and is capable of reducing lipid accumulation. It also ameliorated autophagy in macrophages and atherosclerosis plaques, which play an important role in the step of cholesterol efflux. Altogether, an increase in serum BHB levels after regular exercise is an important mechanism of exercise inhibiting the development of atherosclerosis. This provides a novel treatment for atherosclerotic patients who are unable to undertake regular exercise for whatever reason. They will gain a benefit from receiving additional BHB.


Assuntos
Aterosclerose , Ácido 3-Hidroxibutírico/metabolismo , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Aterosclerose/etiologia , Colesterol/metabolismo , Células Espumosas/metabolismo , Humanos , Macrófagos/metabolismo , Camundongos
18.
Int J Mol Sci ; 23(7)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35409326

RESUMO

The quantity of high-density lipoproteins (HDL) is represented as the serum HDL-C concentration (mg/dL), while the HDL quality manifests as the diverse features of protein and lipid content, extent of oxidation, and extent of glycation. The HDL functionality represents several performance metrics of HDL, such as antioxidant, anti-inflammatory, and cholesterol efflux activities. The quantity and quality of HDL can change during one's lifetime, depending on infection, disease, and lifestyle, such as dietary habits, exercise, and smoking. The quantity of HDL can change according to age and gender, such as puberty, middle-aged symptoms, climacteric, and the menopause. HDL-C can decrease during disease states, such as acute infection, chronic inflammation, and autoimmune disease, while it can be increased by regular aerobic exercise and healthy food consumption. Generally, high HDL-C at the normal level is associated with good HDL quality and functionality. Nevertheless, high HDL quantity is not always accompanied by good HDL quality or functionality. The HDL quality concerns the morphology of the HDL, such as particle size, shape, and number. The HDL quality also depends on the composition of the HDL, such as apolipoproteins (apoA-I, apoA-II, apoC-III, serum amyloid A, and α-synuclein), cholesterol, and triglyceride. The HDL quality is also associated with the extent of HDL modification, such as glycation and oxidation, resulting in the multimerization of apoA-I, and the aggregation leads to amyloidogenesis. The HDL quality frequently determines the HDL functionality, which depends on the attached antioxidant enzyme activity, such as the paraoxonase and cholesterol efflux activity. Conventional HDL functionality is regression, the removal of cholesterol from atherosclerotic lesions, and the removal of oxidized species in low-density lipoproteins (LDL). Recently, HDL functionality was reported to expand the removal of ß-amyloid plaque and inhibit α-synuclein aggregation in the brain to attenuate Alzheimer's disease and Parkinson's disease, respectively. More recently, HDL functionality has been associated with the susceptibility and recovery ability of coronavirus disease 2019 (COVID-19) by inhibiting the activity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The appearance of dysfunctional HDL is frequently associated with many acute infectious diseases and chronic aging-related diseases. An HDL can be a suitable biomarker to diagnose many diseases and their progression by monitoring the changes in its quantity and quality in terms of the antioxidant and anti-inflammatory abilities. An HDL can be a protein drug used for the removal of plaque and as a delivery vehicle for non-soluble drugs and genes. A dysfunctional HDL has poor HDL quality, such as a lower apoA-I content, lower antioxidant ability, smaller size, and ambiguous shape. The current review analyzes the recent advances in HDL quantity, quality, and functionality, depending on the health and disease state during one's lifetime.


Assuntos
COVID-19 , Lipoproteínas HDL , Anti-Inflamatórios , Antioxidantes/metabolismo , Apolipoproteína A-I/metabolismo , Colesterol/metabolismo , HDL-Colesterol , Feminino , Humanos , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Pessoa de Meia-Idade , SARS-CoV-2 , alfa-Sinucleína
19.
Int J Mol Sci ; 23(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408842

RESUMO

Decreasing the levels of certain proteins has been shown to be important for controlling cancer but it is currently unknown whether proteins could potentially be targeted by the inhibiting of protein synthesis. Under this circumstance, targeting protein translation could preferentially affect certain pathways, which could then be of therapeutic advantage when treating cancer. In this report, eukaryotic elongation factor-2 kinase (EEF2K), which is involved in protein translation, was shown to regulate cholesterol metabolism. Targeting EEF2K inhibited key parts of the cholesterol pathway in cancer cells, which could be rescued by the addition of exogenous cholesterol, suggesting that it is a potentially important pathway modulated by targeting this process. Specifically, targeting EEF2K significantly suppressed tumour cell growth by blocking mRNA translation of the cholesterol biosynthesis transcription factor, sterol regulatory element-binding protein (SREBP) 2, and the proteins it regulates. The process could be rescued by the addition of LDL cholesterol taken into the cells via non-receptor-mediated-uptake, which negated the need for SREBP2 protein. Thus, the levels of SREBP2 needed for cholesterol metabolism in cancer cells are therapeutically vulnerable by targeting protein translation. This is the first report to suggest that targeting EEF2K can be used to modulate cholesterol metabolism to treat cancer.


Assuntos
Quinase do Fator 2 de Elongação , Melanoma , Colesterol/metabolismo , Quinase do Fator 2 de Elongação/genética , Quinase do Fator 2 de Elongação/metabolismo , Humanos , Biossíntese de Proteínas , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
20.
Analyst ; 147(9): 1859-1865, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35411359

RESUMO

Small extracellular vesicles (sEVs) have attracted wide attention as a promising tumor biomarker. However, sensitive and selective detection of sEVs is challenging due to the low levels of sEVs in the early stage of cancers. Herein, a novel fluorescent sensor was developed for the detection of sEVs with high sensitivity and selectivity based on nonlinear hybridization chain reaction (nHCR) signal amplification and immunomagnetic separation. Firstly, sEVs were captured and enriched by CD63 antibody conjugated magnetic beads via antibody-antigen reactions. Then, cholesterol-modified DNA probes were anchored spontaneously on lipid membranes of sEVs through efficient hydrophobic interactions between the cholesterol moiety and the phospholipid bilayer of sEVs. The simultaneous recognition of the transmembrane protein and the phospholipid bilayer structure of the sEVs could effectively eliminate interferences from free proteins. The sticky ends of the cholesterol-modified DNA probes acted as the initiator to trigger nHCR to form a hyperbranched network of DNA structure that could recruit more fluorescent signal molecules for signal amplification. Under the optimal conditions, the nHCR-based strategy showed high sensitivity for the detection of sEVs with a limit of detection of 80 particles per µL. In addition, the as-constructed method was successfully applied for the analysis of clinical samples. It provides a sensitive and selective platform for the isolation and detection of sEVs in the early diagnosis of cancers.


Assuntos
Vesículas Extracelulares , Neoplasias , Colesterol/metabolismo , Sondas de DNA/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Separação Imunomagnética , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/metabolismo , Fosfolipídeos/metabolismo
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