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1.
Atherosclerosis ; 392: 117479, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38423808

RESUMO

BACKGROUND AND AIMS: Obesity and type 2 diabetes are significant risk factors for atherosclerotic cardiovascular disease (CVD) worldwide, but the underlying pathophysiological links are poorly understood. Neurotensin (NT), a 13-amino-acid hormone peptide, facilitates intestinal fat absorption and contributes to obesity in mice fed a high-fat diet. Elevated levels of pro-NT (a stable NT precursor produced in equimolar amounts relative to NT) are associated with obesity, type 2 diabetes, and CVD in humans. Whether NT is a causative factor in CVD is unknown. METHODS: Nt+/+ and Nt-/- mice were either injected with adeno-associated virus encoding PCSK9 mutants or crossed with Ldlr-/- mice and fed a Western diet. Atherosclerotic plaques were analyzed by en face analysis, Oil Red O and CD68 staining. In humans, we evaluated the association between baseline pro-NT and growth of carotid bulb thickness after 16.4 years. Lipidomic profiles were analyzed. RESULTS: Atherosclerotic plaque formation is attenuated in Nt-deficient mice through mechanisms that are independent of reductions in circulating cholesterol and triglycerides but associated with remodeling of the plasma triglyceride pool. An increasing plasma concentration of pro-NT predicts atherosclerotic events in coronary and cerebral arteries independent of all major traditional risk factors, indicating a strong link between NT and atherosclerosis. This plasma lipid profile analysis confirms the association of pro-NT with remodeling of the plasma triglyceride pool in atherosclerotic events. CONCLUSIONS: Our findings are the first to directly link NT to increased atherosclerosis and indicate the potential role for NT in preventive and therapeutic strategies for CVD.


Assuntos
Aterosclerose , Camundongos Knockout , Neurotensina , Placa Aterosclerótica , Triglicerídeos , Animais , Neurotensina/sangue , Triglicerídeos/sangue , Aterosclerose/sangue , Humanos , Masculino , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Feminino , Camundongos , Receptores de LDL/genética , Receptores de LDL/deficiência , Fatores de Risco , Ácidos Graxos/metabolismo , Ácidos Graxos/sangue , Pessoa de Meia-Idade , Precursores de Proteínas
2.
Mol Metab ; 65: 101585, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36055578

RESUMO

OBJECTIVE: Sorting-related receptor with type A repeats (SORLA) is a neuronal sorting receptor that prevents accumulation of amyloid-beta peptides, the main constituent of senile plaques in Alzheimer disease. Recent transcriptomic studies show that SORLA transcripts are also found in beta cells of pancreatic islets, yet the role of SORLA in islets is unknown. Based on its protective role in reducing the amyloid burden in the brain, we hypothesized that SORLA has a similar function in the pancreas via regulation of amyloid formation from islet amyloid polypeptide (IAPP). METHODS: We generated human IAPP transgenic mice lacking SORLA (hIAPP:SORLA KO) to assess the consequences of receptor deficiency for islet histopathology and function in vivo. Using both primary islet cells and cell lines, we further investigated the molecular mechanisms whereby SORLA controls the cellular metabolism and accumulation of IAPP. RESULTS: Loss of SORLA activity in hIAPP:SORLA KO resulted in a significant increase in islet amyloid deposits and associated islet cell death compared to hIAPP:SORLA WT animals. Aggravated islet amyloid deposition was observed in mice fed a normal chow diet, not requiring high-fat diet feeding typically needed to induce islet amyloidosis in mouse models. In vitro studies showed that SORLA binds to and mediates the endocytic uptake of proIAPP, but not mature IAPP, delivering the propeptide to an endolysosomal fate. CONCLUSIONS: SORLA functions as a proIAPP-specific clearance receptor, protecting against islet amyloid deposition and associated cell death caused by IAPP.


Assuntos
Amiloidose , Células Secretoras de Insulina , Ilhotas Pancreáticas , Amiloide/genética , Amiloide/metabolismo , Amiloidose/metabolismo , Amiloidose/patologia , Animais , Humanos , Células Secretoras de Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/genética , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/metabolismo , Proteínas de Membrana Transportadoras/deficiência , Proteínas de Membrana Transportadoras/genética , Camundongos , Camundongos Transgênicos , Receptores de LDL/deficiência , Receptores de LDL/genética
3.
Front Immunol ; 13: 821423, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35145523

RESUMO

Increased glutamine metabolism by macrophages is associated with development of atherosclerotic lesions. Positron emission tomography/computed tomography (PET/CT) with a glutamine analog (2S,4R)-4-18F-fluoroglutamine (18F-FGln) allows quantification of glutamine consumption in vivo. Here, we investigated uptake of 18F-FGln by atherosclerotic lesions in mice and compared the results with those obtained using the glucose analog 2-deoxy-2-18F-fluoro-D-glucose (18F-FDG). Uptake of 18F-FGln and 18F-FDG by healthy control mice (C57BL/6JRj) and atherosclerotic low-density lipoprotein receptor-deficient mice expressing only apolipoprotein B100 (LDLR-/-ApoB100/100) was investigated. The mice were injected intravenously with 18F-FGln or 18F-FDG for in vivo PET/CT imaging. After sacrifice at 70 minutes post-injection, tracer uptake was analyzed by gamma counting of excised tissues and by autoradiography of aorta cryosections, together with histological and immunohistochemical analyses. We found that myocardial uptake of 18F-FGln was low. PET/CT detected lesions in the aortic arch, with a target-to-background ratio (SUVmax, aortic arch/SUVmean, blood) of 1.95 ± 0.42 (mean ± standard deviation). Gamma counting revealed that aortic uptake of 18F-FGln by LDLR-/-ApoB100/100 mice (standardized uptake value [SUV], 0.35 ± 0.06) was significantly higher than that by healthy controls (0.20 ± 0.08, P = 0.03). More detailed analysis by autoradiography revealed that the plaque-to-healthy vessel wall ratio of 18F-FGln (2.90 ± 0.42) was significantly higher than that of 18F-FDG (1.93 ± 0.22, P = 0.004). Immunohistochemical staining confirmed that 18F-FGln uptake in plaques co-localized with glutamine transporter SLC7A7-positive macrophages. Collectively these data show that the 18F-FGln PET tracer detects inflamed atherosclerotic lesions. Thus, exploiting glutamine consumption using 18F-FGln PET may have translational relevance for studying atherosclerotic inflammation.


Assuntos
Aterosclerose/diagnóstico por imagem , Glutamina/análogos & derivados , Placa Aterosclerótica/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Animais , Apolipoproteína B-100/genética , Aterosclerose/metabolismo , Modelos Animais de Doenças , Fluordesoxiglucose F18 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de LDL/deficiência , Receptores de LDL/genética
4.
Sci Rep ; 12(1): 483, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013582

RESUMO

Protein arginine methyltransferase 3 (PRMT3) is a co-activator of liver X receptor capable of selectively modulating hepatic triglyceride synthesis. Here we investigated whether pharmacological PRMT3 inhibition can diminish the hepatic steatosis extent and lower plasma lipid levels and atherosclerosis susceptibility. Hereto, male hyperlipidemic low-density lipoprotein receptor knockout mice were fed an atherogenic Western-type diet and injected 3 times per week intraperitoneally with PRMT3 inhibitor SGC707 or solvent control. Three weeks into the study, SGC707-treated mice developed severe pruritus and scratching-associated skin lesions, leading to early study termination. SGC707-treated mice exhibited 50% lower liver triglyceride stores as well as 32% lower plasma triglyceride levels. Atherosclerotic lesions were virtually absent in all experimental mice. Plasma metabolite analysis revealed that levels of taurine-conjugated bile acids were ~ threefold increased (P < 0.001) in response to SGC707 treatment, which was paralleled by systemically higher bile acid receptor TGR5 signalling. In conclusion, we have shown that SGC707 treatment reduces hepatic steatosis and plasma triglyceride levels and induces pruritus in Western-type diet-fed LDL receptor knockout mice. These findings suggest that pharmacological PRMT3 inhibition can serve as therapeutic approach to treat non-alcoholic fatty liver disease and dyslipidemia/atherosclerosis, when unwanted effects on cholesterol and bile acid metabolism can be effectively tackled.


Assuntos
Dieta Ocidental/efeitos adversos , Fígado Gorduroso/tratamento farmacológico , Isoquinolinas/efeitos adversos , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Prurido/etiologia , Receptores de LDL/genética , Triglicerídeos/sangue , Animais , Fígado Gorduroso/metabolismo , Humanos , Isoquinolinas/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Prurido/genética , Prurido/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de LDL/deficiência
5.
Int J Mol Sci ; 22(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34830135

RESUMO

Dyslipidemia is commonly linked to skeletal muscle dysfunction, accumulation of intramyocellular lipids, and insulin resistance. However, our previous research indicated that dyslipidemia in apolipoprotein E and low-density lipoprotein receptor double knock-out mice (ApoE/LDLR -/-) leads to improvement of exercise capacity. This study aimed to investigate in detail skeletal muscle function and metabolism in these dyslipidemic mice. We found that ApoE/LDLR -/- mice showed an increased grip strength as well as increased troponins, and Mhc2 levels in skeletal muscle. It was accompanied by the increased skeletal muscle mitochondria numbers (judged by increased citrate synthase activity) and elevated total adenine nucleotides pool. We noted increased triglycerides contents in skeletal muscles and increased serum free fatty acids (FFA) levels in ApoE/LDLR -/- mice. Importantly, Ranolazine mediated inhibition of FFA oxidation in ApoE/LDLR -/- mice led to the reduction of exercise capacity and total adenine nucleotides pool. Thus, this study demonstrated that increased capacity for fatty acid oxidation, an adaptive response to dyslipidemia leads to improved cellular energetics that translates to increased skeletal muscle strength and contributes to increased exercise capacity in ApoE/LDLR -/- mice.


Assuntos
Dislipidemias/fisiopatologia , Ácidos Graxos/metabolismo , Resistência à Insulina/fisiologia , Força Muscular/fisiologia , Nucleotídeos de Adenina/metabolismo , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Glicemia/metabolismo , Dislipidemias/genética , Dislipidemias/metabolismo , Ácidos Graxos/sangue , Resistência à Insulina/genética , Lipídeos/sangue , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias Musculares/metabolismo , Força Muscular/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Cadeias Pesadas de Miosina/metabolismo , Oxirredução/efeitos dos fármacos , Ranolazina/farmacologia , Receptores de LDL/deficiência , Receptores de LDL/genética , Troponina/metabolismo
7.
Mol Metab ; 54: 101335, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34530175

RESUMO

OBJECTIVE: An increased ω6/ω3-polyunsaturated fatty acid ratio in the current Western diet is regarded as a critical epigenetic nutritional factor in the pathogenesis of several human lifestyle diseases, metabolic syndrome, cardiovascular disease, the central nervous system and the female and male reproductive systems. The impact of nutrient ω3-and ω6-PUFAs in the pathogenesis of dyslipoproteinemia and atherosclerosis has been a topic of intense efforts for several decades. Cellular homeostasis of the ω3-and ω6- PUFA pool is maintained by the synthesis of ω3-and ω6-PUFAs from essential fatty acids (EFA) (linoleic and α-linolenic acid) and their dietary supply. In this study, we used the auxotrophic Δ6-fatty acid desaturase- (FADS2) deficient mouse (fads2-/-), an unbiased model congenial for stringent feeding experiments, to investigate the molecular basis of the proposed protective role of dietary ω3-and ω6-PUFAs (Western diet) in the pathogenesis of multifactorial dyslipoproteinemia and atherosclerosis. We focused on the metabolic axis-liver endoplasmic reticulum (ER), serum lipoprotein system (Lp) and aorta vessel wall. Furthermore, we addressed the impact of the inactivated fads2-locus with inactivated PUFA synthesis on the development and progression of extended atherosclerosis in two different mouse mutants with disrupted cholesterol homeostasis, using the apoe-/- and ldlr-/- mutants and the fads2-/- x apoe-/- and fads2-/- x ldlr-/- double mutants. METHODS: Cohorts of +/+ and fads2-/- mice underwent two long-term dietary regimens: a) a PUFA-free standard chow diet containing only EFAs, essential for viability, and b) a high fat/high cholesterol (HFHC) diet, a mimicry of the human atherogenic "Western" diet. c) To study the molecular impact of PUFA synthesis deficiency on the development and progression of atherosclerosis in the hypercholesterolemic apoe-/- and ldlr-/- mouse models fed PUFA-free regular and sustained HFHC diets, we generated the fads2-/- x apoe-/- and the fads2-/- x ldlr-/- double knockout mutants. We assessed essential molecular, biochemical and cell biological links between the diet-induced modified lipidomes of the membrane systems of the endoplasmic reticulum/Golgi complex, the site of lipid synthesis, the PL monolayer and neutral lipid core of LD and serum-Lp profiles and cellular reactions in the aortic wall. RESULTS: ω3-and ω6-PUFA synthesis deficiency in the fads2-/- mouse causes a) hypocholesterolemia and hypotriglyceridemia, b) dyslipoproteinemia with a shift of high-density lipoprotein (HDL) to very low-density lipoprotein (VLDL)-enriched Lp-pattern and c) altered liver lipid droplet structures. d) Long-term HFHC diet does not trigger atherosclerotic plaque formation in the aortic arc, the thoracic and abdominal aorta of PUFA-deficient fads2-/- mice. Inactivation of the fads2-/- locus, abolishing systemic PUFA synthesis in the fads2-/- x apoe-/- and fads2-/- x ldlr-/- double knockout mouse lines. CONCLUSIONS: Deficiency of ω3-and ω6-PUFA in the fads2-/- mutant perturbs liver lipid metabolism, causes hypocholesterolemia and hypotriglyceridemia and renders the fads2-/- mutant resistant to sustained atherogenic HFHC diet. Neither PUFA-free regular nor long-term HFHC-diet impacts the apoe- and LDL-receptor deficiency-provoked hypercholesterolemia and atherosclerotic plaque formation, size and distribution in the aorta. Our study strongly suggests that the absence of PUFAs as highly vulnerable chemical targets of autoxidation attenuates inflammatory responses and the formation of atherosclerotic lesions. The cumulative data and insight into the molecular basis of the pleiotropic functions of PUFAs challenge a differentiated view of PUFAs as culprits or benefactors during a lifespan, pivotal for legitimate dietary recommendations.


Assuntos
Aterosclerose/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Ômega-3/biossíntese , Ácidos Graxos Ômega-6/biossíntese , Receptores de LDL/metabolismo , Animais , Colesterol na Dieta/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos Dessaturases/deficiência , Ácidos Graxos Dessaturases/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de LDL/deficiência
8.
Lipids Health Dis ; 20(1): 101, 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34511120

RESUMO

BACKGROUND: As an autosomal dominant disorder, familial hypercholesterolemia (FH) is mainly attributed to disease-causing variants in the low-density lipoprotein receptor (LDLR) gene. The aim of this study was to explore the molecular mechanism of LDLR c.501C>A variant in FH and assess the efficacy of proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitor treatment for FH patients. METHODS: The whole-exome sequencing was performed on two families to identify disease-causing variants, which were verified by Sanger sequencing. The function of LDLR variant was further explored in HEK293 cells by Western Blot and confocal microscopy. Besides, the therapeutic effects of PCSK9 inhibitor treatment for two probands were assessed for 3 months. RESULTS: All members of the two families with the LDLR c.501C>A variant showed high levels of LDLC. The relationship between the clinical phenotype and LDLR variants was confirmed in the current study. Both in silico and in vitro analyses showed that LDLR c.501C>A variant decreased LDLR expression and LDL uptake. PCSK9 inhibitor treatment lowered the lipid level in proband 1 by 24.91%. However, the treatment was ineffective for proband 2. A follow-up study revealed that the PCSK9 inhibitor treatment had low ability of lipid-lowering effect in the patients. CONCLUSIONS: LDLR c.501C>A variant might be pathogenic for FH. The PCSK9 inhibitor therapy is not a highly effective option for treatment of FH patients with LDLR c.501C>A variant.


Assuntos
Hiperlipoproteinemia Tipo II/genética , Mutação Puntual , Pró-Proteína Convertase 9/genética , Receptores de LDL/genética , Adolescente , Adulto , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Família , Feminino , Regulação da Expressão Gênica , Células HEK293 , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/patologia , Hipolipemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Inibidores de PCSK9/uso terapêutico , Linhagem , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/deficiência , Falha de Tratamento , Triglicerídeos/sangue , Sequenciamento do Exoma
9.
FASEB J ; 35(10): e21892, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34569651

RESUMO

Atherosclerosis is a chronic inflammatory disorder of the vasculature regulated by cytokines. We have previously shown that extracellular signal-regulated kinase-1/2 (ERK1/2) plays an important role in serine 727 phosphorylation of signal transducer and activator of transcription-1 (STAT1) transactivation domain, which is required for maximal interferon-γ signaling, and the regulation of modified LDL uptake by macrophages in vitro. Unfortunately, the roles of ERK1/2 and STAT1 serine 727 phosphorylation in atherosclerosis are poorly understood and were investigated using ERK1 deficient mice (ERK2 knockout mice die in utero) and STAT1 knock-in mice (serine 727 replaced by alanine; STAT1 S727A). Mouse Atherosclerosis RT² Profiler PCR Array analysis showed that ERK1 deficiency and STAT1 S727A modification produced significant changes in the expression of 18 and 49 genes, respectively, in bone marrow-derived macrophages, with 17 common regulated genes that included those that play key roles in inflammation and cell migration. Indeed, ERK1 deficiency and STAT1 S727A modification attenuated chemokine-driven migration of macrophages with the former also impacting proliferation and the latter phagocytosis. In LDL receptor deficient mice fed a high fat diet, both ERK1 deficiency and STAT1 S727A modification produced significant reduction in plaque lipid content, albeit at different time points. The STAT1 S727A modification additionally caused a significant reduction in plaque content of macrophages and CD3 T cells and diet-induced cardiac hypertrophy index. In addition, there was a significant increase in plasma IL-2 levels and a trend toward increase in plasma IL-5 levels. These studies demonstrate important roles of STAT1 S727 phosphorylation in particular in the regulation of atherosclerosis-associated macrophage processes in vitro together with plaque lipid content and inflammation in vivo, and support further assessment of its therapeutical potential.


Assuntos
Macrófagos/metabolismo , Placa Aterosclerótica/metabolismo , Receptores de LDL/deficiência , Fator de Transcrição STAT1/metabolismo , Animais , Técnicas de Introdução de Genes , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/patologia , Camundongos , Camundongos Knockout , Fosforilação , Placa Aterosclerótica/genética , Placa Aterosclerótica/patologia , Receptores de LDL/metabolismo , Fator de Transcrição STAT1/genética
10.
Arterioscler Thromb Vasc Biol ; 41(9): 2399-2416, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34289702

RESUMO

Objective: Vascular smooth muscle cell (VSMC) plasticity plays a critical role in the development of atherosclerosis. Long noncoding RNAs (lncRNAs) are emerging as important regulators in the vessel wall and impact cellular function through diverse interactors. However, the role of lncRNAs in regulating VSMCs plasticity and atherosclerosis remains unclear. Approach and Results: We identified a VSMC-enriched lncRNA cardiac mesoderm enhancer-associated noncoding RNA (CARMN) that is dynamically regulated with progression of atherosclerosis. In both mouse and human atherosclerotic plaques, CARMN colocalized with VSMCs and was expressed in the nucleus. Knockdown of CARMN using antisense oligonucleotides in Ldlr−/− mice significantly reduced atherosclerotic lesion formation by 38% and suppressed VSMCs proliferation by 45% without affecting apoptosis. In vitro CARMN gain- and loss-of-function studies verified effects on VSMC proliferation, migration, and differentiation. TGF-ß1 (transforming growth factor-beta) induced CARMN expression in a Smad2/3-dependent manner. CARMN regulated VSMC plasticity independent of the miR143/145 cluster, which is located in close proximity to the CARMN locus. Mechanistically, lncRNA pulldown in combination with mass spectrometry analysis showed that the nuclear-localized CARMN interacted with SRF (serum response factor) through a specific 600­1197 nucleotide domain. CARMN enhanced SRF occupancy on the promoter regions of its downstream VSMC targets. Finally, knockdown of SRF abolished the regulatory role of CARMN in VSMC plasticity. Conclusions: The lncRNA CARMN is a critical regulator of VSMC plasticity and atherosclerosis. These findings highlight the role of a lncRNA in SRF-dependent signaling and provide implications for a range of chronic vascular occlusive disease states.


Assuntos
Aterosclerose/metabolismo , Plasticidade Celular , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , RNA Longo não Codificante/metabolismo , Fator de Resposta Sérica/metabolismo , Animais , Aterosclerose/genética , Aterosclerose/patologia , Linhagem Celular , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Fenótipo , Placa Aterosclerótica , RNA Longo não Codificante/genética , Receptores de LDL/deficiência , Receptores de LDL/genética , Fator de Resposta Sérica/genética , Transdução de Sinais
11.
Nutrients ; 13(7)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202724

RESUMO

BACKGROUND: A low-sodium (LS) diet reduces blood pressure, contributing to the prevention of cardiovascular diseases. However, intense dietary sodium restriction impairs insulin sensitivity and worsens lipid profile. Considering the benefits of aerobic exercise training (AET), the effect of LS diet and AET in hepatic lipid content and gene expression was investigated in LDL receptor knockout (LDLr-KO) mice. METHODS: Twelve-week-old male LDLr-KO mice fed a normal sodium (NS) or LS diet were kept sedentary (S) or trained (T) for 90 days. Body mass, plasma lipids, insulin tolerance testing, hepatic triglyceride (TG) content, gene expression, and citrate synthase (CS) activity were determined. Results were compared by 2-way ANOVA and Tukey's post-test. RESULTS: Compared to NS, LS increased body mass and plasma TG, and impaired insulin sensitivity, which was prevented by AET. The LS-S group, but not the LS-T group, presented greater hepatic TG than the NS-S group. The LS diet increased the expression of genes related to insulin resistance (ApocIII, G6pc, Pck1) and reduced those involved in oxidative capacity (Prkaa1, Prkaa2, Ppara, Lipe) and lipoprotein assembly (Mttp). CONCLUSION: AET prevented the LS-diet-induced TG accumulation in the liver by improving insulin sensitivity and the expression of insulin-regulated genes and oxidative capacity.


Assuntos
Dieta Hipossódica/efeitos adversos , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/fisiologia , Condicionamento Físico Animal/fisiologia , Receptores de LDL/deficiência , Animais , Peso Corporal , Citrato (si)-Sintase/metabolismo , Expressão Gênica , Lipídeos/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout , Sódio na Dieta/metabolismo , Triglicerídeos/metabolismo
12.
Cardiovasc Ther ; 2021: 5596590, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113390

RESUMO

INTRODUCTION: In the animal model, preconditioning is a powerful weapon against ischemic damage. The reason why the human heart cannot be protected from ischemic damage by preconditioning remains unclear. There are assumptions that the lack of preconditioning in humans is caused by concomitant diseases such as dyslipoproteinemia and arteriosclerosis. This study investigates whether dyslipoproteinemia and the resulting arteriosclerosis can be a cause of a reduced precondition effect of heart in mice. METHODS: LDL receptor-deficient mice were fed a long-term (14-16 weeks) high-fat atherogenic diet to induce arteriosclerosis. Arteriosclerosis was identified by histological examination and vessel contraction tests. LDLR-/- and wild-type mice were randomly assigned to anesthetic-induced, remote ischemic, or no preconditioning. All mice were subjected to 45 minutes of coronary artery occlusion and 180 minutes of reperfusion. The area at risk and infarct size were determined by Evans Blue and triphenyltetrazolium chloride staining. RESULTS: Histopathological examination showed atherosclerosis in high-fat atherogenic fed LDLR-/- mice, and the vessel relaxation capacity was significantly reduced compared to wild-type mice. In the wild type, as expected, infarct size was significantly reduced by preconditioning compared to the control. In LDLR-/- mice, infarct size was significantly reduced by preconditioning compared to the control. Surprisingly, the LDLR-/- control group also had a significantly reduced infarct size compared to the wild-type control group. CONCLUSION: We were able to demonstrate that a high-fat diet morphologically and functionally triggered atherosclerosis in LDLR-/- mice. Interestingly, LDLR-/- mice with an atherogenic diet had smaller infarct sizes compared to wild-type mice. Moreover, preconditioning additionally reduced myocardial infarct size in LDLR-/- mice. A long-term high-fat atherogenic diet and preconditioning seem to result in additive cardioprotection in LDLR-/- mice.


Assuntos
Anestésicos/farmacologia , Aterosclerose/patologia , Dislipidemias/patologia , Precondicionamento Isquêmico Miocárdico/métodos , Infarto do Miocárdio/patologia , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/patologia , Distribuição Aleatória , Receptores de LDL/deficiência
13.
J Lipid Res ; 62: 100091, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34118252

RESUMO

Plasma LDL is produced from catabolism of VLDL and cleared from circulation mainly via the hepatic LDL receptor (LDLR). Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes LDLR degradation, increasing plasma LDL-C levels. Circulating PCSK9 is mainly secreted by the liver, whereas VLDL is exclusively secreted by hepatocytes. However, the mechanism regulating their secretion is not completely understood. Surfeit 4 (Surf4) is a cargo receptor localized in the ER membrane. It recruits cargos into coat protein complex II vesicles to facilitate their secretion. Here, we investigated the role of Surf4 in VLDL and PCSK9 secretion. We generated Surf4 liver-specific knockout mice and found that knockout of Surf4 did not affect PCSK9 secretion, whereas it significantly reduced plasma levels of cholesterol, triglyceride, and lipid-binding protein apolipoprotein B (apoB). In cultured human hepatocytes, Surf4 coimmunoprecipitated and colocalized with apolipoprotein B100, and Surf4 silencing reduced secretion of apolipoprotein B100. Furthermore, knockdown of Surf4 in LDLR knockout (Ldlr-/-) mice significantly reduced triglyceride secretion, plasma levels of apoB and non-HDL-C, and the development of atherosclerosis. However, Surf4 liver-specific knockout mice and Surf4 knockdown in Ldlr-/- mice displayed similar levels of liver lipids and plasma alanine aminotransferase activity as control mice, indicating that inhibition of Surf4 does not cause notable liver damage. Expression of stearoyl-CoA desaturase-1 was also reduced in the liver of these mice, suggesting a reduction in de novo lipogenesis. In summary, hepatic deficiency of Surf4 reduced VLDL secretion and the development of atherosclerosis but did not cause significant hepatic lipid accumulation or liver damage.


Assuntos
Aterosclerose/metabolismo , Lipoproteínas VLDL/metabolismo , Proteínas de Membrana/metabolismo , Animais , Células Cultivadas , Proteínas de Membrana/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pró-Proteína Convertase 9/deficiência , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/deficiência , Receptores de LDL/metabolismo
14.
Int J Radiat Biol ; 97(9): 1270-1281, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34032557

RESUMO

BACKGROUND: Radiation exposure is known to increase the risk of chronic inflammatory diseases, such as atherosclerosis, by modulating inflammation. METHODS: To investigate the infiltration of leukocytes in radiation-aggravated atherosclerosis, we examined low-density lipoprotein receptor-deficient (Ldlr-/-) mice and C57BL/6j mice after exposure to 0.5 or 1 Gy radiation over 16 weeks. RESULTS: We found that radiation exposure induced atherosclerosis development in Ldlr-/- mice, as demonstrated by increased lipid-laden plaque size, reactive oxygen species levels, and levels of the pro-inflammatory cytokines, IL-1ß and TNF-α, in the aortas and spleens. Total plasma cholesterol, triglyceride, and LDL cholesterol levels were also increased by radiation exposure, along with cardiovascular risk. We also showed dose-dependent increases in neutrophils and monocytes that coincided with a reduction in lymphocytes in the spleens of Ldlr-/- mice. The correlation between the infiltration of leukocytes and cytokine production was also confirmed in the hearts and spleens of these mice. CONCLUSIONS: We concluded that chronic radiation exposure increased the production of pro-inflammatory mediators, which was associated with the migration of neutrophils and inflammatory monocytes into sites of atherosclerosis. Thus, our data suggest that the accumulation of neutrophils and inflammatory monocytes, together with the reduction of lymphocytes, contribute to aggravated atherosclerosis in Ldlr-/- mice under prolonged exposure to radiation.


Assuntos
Aterosclerose/imunologia , Infiltração de Neutrófilos/efeitos da radiação , Animais , Aterosclerose/sangue , Aterosclerose/patologia , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de LDL/deficiência , Fator de Necrose Tumoral alfa/sangue
17.
J Cardiovasc Pharmacol ; 77(5): 660-672, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33760798

RESUMO

ABSTRACT: Desialylation, governed by sialidases or neuraminidases, is strongly implicated in a wide range of human disorders, and accumulative data show that inhibition of neuraminidases, such as neuraminidases 1 sialidase, may be useful for managing atherosclerosis. Several studies have reported promising effects of oseltamivir phosphate, a widely used anti-influenza sialidase inhibitor, on human cancer cells, inflammation, and insulin resistance. In this study, we evaluated the effects of oseltamivir phosphate on atherosclerosis and thrombosis and potential liver toxicity in LDLR-/- mice fed with high-fat diet. Our results showed that oseltamivir phosphate significantly decreased plasma levels of LDL cholesterol and elastin fragmentation in aorta. However, no effect was observed on both atherosclerotic plaque size in aortic roots and chemically induced thrombosis in carotid arteries. Importantly, oseltamivir phosphate administration had adverse effects on the liver of mice and significantly increased messenger RNA expression levels of F4/80, interleukin-1ß, transforming growth factor-ß1, matrix metalloproteinase-12, and collagen. Taken together, our findings suggest that oseltamivir phosphate has limited benefits on atherosclerosis and carotid thrombosis and may lead to adverse side effects on the liver with increased inflammation and fibrosis.


Assuntos
Antivirais/toxicidade , Doenças da Aorta/tratamento farmacológico , Aterosclerose/tratamento farmacológico , Trombose das Artérias Carótidas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Fígado/efeitos dos fármacos , Oseltamivir/toxicidade , Receptores de LDL/deficiência , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Trombose das Artérias Carótidas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Camundongos Knockout , Placa Aterosclerótica , Receptores de LDL/genética , Medição de Risco
18.
Arterioscler Thromb Vasc Biol ; 41(4): 1309-1318, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33626909

RESUMO

[Figure: see text].


Assuntos
Anticorpos Neutralizantes/farmacologia , Aterosclerose/prevenção & controle , Moléculas de Adesão Celular Neuronais/antagonistas & inibidores , Adesão Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Proteínas da Matriz Extracelular/antagonistas & inibidores , Migração e Rolagem de Leucócitos/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Proteínas do Tecido Nervoso/antagonistas & inibidores , Oligonucleotídeos Antissenso/farmacologia , Animais , Aterosclerose/genética , Aterosclerose/imunologia , Aterosclerose/metabolismo , Receptor 1 de Quimiocina CX3C/genética , Moléculas de Adesão Celular Neuronais/deficiência , Moléculas de Adesão Celular Neuronais/genética , Técnicas de Cocultura , Modelos Animais de Doenças , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Proteínas da Matriz Extracelular/deficiência , Proteínas da Matriz Extracelular/genética , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Proteínas Relacionadas a Receptor de LDL/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Masculino , Camundongos Transgênicos , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Placa Aterosclerótica , Receptores de LDL/deficiência , Receptores de LDL/genética , Proteína Reelina , Serina Endopeptidases/deficiência , Serina Endopeptidases/genética , Transdução de Sinais , Células U937
20.
J Nutr ; 151(4): 902-910, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33561256

RESUMO

BACKGROUND: Epidemiologic studies suggest that fruit and vegetable (F&V) consumption is inversely associated with incidence of cardiovascular disease (CVD). However, evidence for causality is lacking, and the underlying mechanisms are not well understood. OBJECTIVES: We aimed to determine whether there is a causal relation between consuming high levels of F&V and prevention of atherosclerosis, the hallmark of CVD pathogenesis. Furthermore, the underlying mechanisms were determined. METHODS: Six-week-old male LDL receptor-knockout mice were randomly assigned to 3 diet groups (12 mice/group) for 20 wk: control (CON, 10% kcal fat, 0.20 g/kg cholesterol), atherogenic (Ath, 27% kcal fat, 0.55 g/kg cholesterol), and Ath supplemented with 15% F&V (Ath + FV) (equivalent to 8-9 servings/d in humans). F&V was added as a freeze-dried powder that was prepared from the 24 most commonly consumed F&Vs in the United States. Body weight, aortic atherosclerotic lesion area, hepatic steatosis area, serum lipid profile and proinflammatory cytokine TNF-α concentrations, gut microbiota, and liver TNF-α and fatty acid synthase (Fasn) mRNA concentrations were assessed. RESULTS: F&V supplementation did not affect weight gain. Mice fed the Ath + FV diet had a smaller aortic atherosclerotic lesion area (71.7% less) and hepatic steatosis area (80.7% less) than those fed the Ath diet (both P < 0.001) independent of impact on weight, whereas no difference was found between Ath + FV and CON groups in these 2 pathologic markers. Furthermore, F&V supplementation prevented Ath diet-induced dyslipidemia (high concentrations of serum TG and VLDL cholesterol and lower concentrations of HDL cholesterol), reduced serum TNF-α concentration (by 21.5%), suppressed mRNA expression of liver TNF-α and Fasn, and ameliorated Ath-induced gut microbiota dysbiosis. CONCLUSIONS: Our results indicate that consuming a large quantity and variety of F&Vs causally attenuates diet-induced atherosclerosis and hepatic steatosis in mice. These effects of F&Vs are associated with, and may be mediated through, improved atherogenic dyslipidemia, alleviated gut dysbiosis, and suppressed inflammation.


Assuntos
Aterosclerose/dietoterapia , Aterosclerose/prevenção & controle , Frutas , Receptores de LDL/deficiência , Verduras , Animais , Aterosclerose/etiologia , Dieta Aterogênica/efeitos adversos , Suplementos Nutricionais , Microbioma Gastrointestinal , Teste de Tolerância a Glucose , Fatores de Risco de Doenças Cardíacas , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Receptores de LDL/genética , Fator de Necrose Tumoral alfa/sangue , Aumento de Peso
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